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Friday, August 24, 2007
Thursday, August 23, 2007
DATADIC
SAP R/3 DATA DICTIONARY QUESTIONS What are the layers of data description in R/3?
· The external layer.
· The ABAP/4 layer.
· The database layer.
Define external layer?
The external layer is the plane at which the user sees and interacts with the data, that is, the data format in the user interface. This data format is independent of the database system used.
Define ABAP/4 layer?
The ABAP/4 layer describes the data formats used by the ABAP/4 processor.
Define Database layer?
The database layer describes the data formats used in the database.
What is a Data Class?
The Data class determines in which table space the table is stored when it is created in the database.
What is a Size Category?
The Size category describes the probable space requirement of the table in the database.
How many types of size categories and data classes are there?
There are five size categories (0-4) and 11 data classes only three of which are appropriate for application tables:
· APPL0- Master data (data frequently accessed but rarely updated).
· APPL1- Transaction data (data that is changed frequently).
· APPL2- Organizational data (customizing data that is entered when system is configured and then rarely changed).
The other two types are:
· USR
· USR1 – Intended for customer’s own developments.
What are control tables?
The values specified for the size category and data class are mapped to database-specific values via control tables.
What is the function of the transport system and workbench organizer?
The function of the transport system and the Workbench Organizer is to manage any changes made to objects of the ABAP/4 Development Workbench and to transport these changes between different SAP systems.
What is a table pool?
A table pool (or pool) is used to combine several logical tables in the ABAP/4 Dictionary. The definition of a pool consists of at least two key fields and a long argument field (VARDATA).
What are pooled tables?
These are logical tables, which must be assigned to a table pool when they are defined. Pooled tables can be used to store control data (such as screen sequences or program parameters).
What is a table cluster?
A table cluster combines several logical tables in the ABAP/4 Dictionary. Several logical rows from different cluster tables are brought together in a single physical record. The records from the cluster tables assigned to a cluster are thus stored in a single common table in the database.
How can we access the correction and transport system?
Each time you create a new object or change an existing object in the ABAP/4 Dictionary, you branch automatically to the Workbench Organizer or correction and transport system.
Which objects are independent transport objects?
Domains, Data elements, Tables, Technical settings for tables, Secondary indexes for transparent tables, Structures, Views, Matchcode objects, Matchcode Ids, Lock objects.
How is conversion of data types done between ABAP/4 & DB layer?
Conversion between ABAP/4 data types and the database layer is done within the database interface.
How is conversion of data types done between ABAP/4 & external level?
Conversion between the external layer and the ABAP/4 layer is done in the SAP dialog manager DYNP.
What are the Data types of the external layer?
ACCP, Char, CLNT, CUKY, CURR, DATS, DESC, FLTP, INT1, INT2, INT4, LANG, LCHR, LRAW, NUMC, PREC, QUAN, RAW, TIMS, UNIT,VARC.
What are the Data types of the ABAP/4 layer?
Possible ABAP/4 data types:
C: Character.
D: Date, format YYYYMMDD.
F: Floating-point number in DOUBLE PRECISION (8 bytes).
I: Integer.
N: Numerical character string of arbitrary length.
P: Amount of counter field (packed; implementation depends on h/w platform).
S: Time Stamp YYYYMMDDHHMMSS.
V: Character string of variable length, length is given in the first two bytes.
X: Hexadecimal (binary) storage.
How can we set the table spaces and extent sizes?
You can specify the extent sizes and the table space (physical storage area in the database) in which a transparent table is to be stored by setting the size category and data class.
What is the function of the correction system?
The correction system manages changes to internal system components. Such as objects of the ABAP/4 Dictionary.
What are local objects?
Local objects (Dev class$TMP) are independent of correction and transport system.
What is a Development class?
Related objects from the ABAP/4 repository are assigned to the same development class. This enables you to correct and transport related objects as a unit.
What is a data dictionary?
Data Dictionary is a central source of data in a data management system. Its main function is to support the creation and management of data definitions. It has details about
· what data is contained?
· What are the attributes of the data?
· What is the relationship existing between the various data elements?
What functions does a data dictionary perform?
In a data management system, the principal functions performed by the data dictionary are
· Management of data definitions.
· Provision of information for evaluation.
· Support for s/w development.
· Support form documentation.
· Ensuring that the data definitions are flexible and up-to-date.
What are the features of ABAP/4 Dictionary?
The most important features are:
· Integrated to aABAP/4 Development Workbench.
· Active in the runtime environment.
What are the uses of the information in the Data dictionary?
The following information is directly taken from the Data dictionary:
· Information on fields displayed with F1 help.
· Possible entries for fields displayed with F4 help.
· Matchcode and help views search utilities.
What are the basic objects of the data dictionary?
· Tables
· Domains
· Data elements
· Structures
· Foreign Keys
What are the aggregate objects in the data dictionary?
· Views
· Match codes
· Lock objects.
In the ABAP/4 Dictionary Tables can be defined independent of the underlying database (T/F).
True.
ABAP/4 Dictionary contains the Logical definition of the table.
A field containing currency amounts (data type CURR) must be assigned to a reference table and a reference field. Explain.
As a reference table, a system containing all the valid currencies is assigned or any other table, which contains a field with the currency key format. This field is called as reference field. The assignment of the field containing currency amounts to the reference field is made at runtime. The value in the reference field determines the currency of the amount.
A field containing quantity amounts (data type QUAN) must be assigned to a reference table and a reference field. Explain?
As a reference table, a system table containing all the valid quantity units is assigned or any other table, which contains a field with the format or quantity units (data type UNIT). This field is called as reference field.
The assignment of the field containing quantity amounts to the reference field is made at runtime. The value in the reference field determines the quantity unit of the amount.
What is the significance of Technical settings (specified while creating a table in the data dictionary)? By specifying technical settings we can control how database tables are created in the database. The technical settings allows us to
· Optimize storage space requirements.
· Table access behavior.
· Buffering required.
· Changes to entries logged.
What is a Table attribute?
The table’s attributes determine who is responsible for maintaining a table and which types of access are allowed for the table. The most important table attributes are:
· Delivery class.
· Table maintenance allowed.
· Activation type.
What is the significance of Delivery Class?
· The delivery class controls the degree to which the SAP or the customer is responsible for table maintenance.
· Whether SAP provides the table with or without contents.
· Determines the table type.
· Determines how the table behaves when it is first installed, at upgrade, when it is transported, and when a client copy is performed.
What is the max. no. Of structures that can be included in a table or structure.
Nine.
What are two methods of modifying SAP standard tables?
· Append Structures and
· Customizing Includes.
What is the difference between a Substructure and an Append Structure?
· In case of a substructure, the reference originates in the table itself, in the form of a statement include….
· In case of an append structure, the table itself remains unchanged and the reference originates in the append structure.
To how many tables can an append structure be assigned.
One.
If a table that is to be extended contains a long field, we cannot use append structures why?
Long fields in a table must always be located in the end, as the last field of the table. If a table has an append structure the append line must also be on the last field of the table.
Can we include customizing include or an append structure with Pooled or Cluster tables?
No.
What are the two ways for restricting the value range for a domain?
· By specifying fixed values.
· By stipulating a value table.
Structures can contain data only during the runtime of a program (T/F)
True.
What are the aggregate objects in the Dictionary?
· Views
· Match Code.
· Lock Object.
What are base tables of an aggregate object?
The tables making up an aggregate object (primary and secondary) are called aggregate object.
The data of a view is not physically stored, but derived from one or more tables (t/f)
True.
What are the 2 other types of Views, which are not allowed in Release 3.0?
· Structure Views.
· Entity Views.
What is a Match Code?
Match code is a tool to help us to search for data records in the system. Match Codes are an efficient and user-friendly search aid where key of a record is unknown.
What are the two levels in defining a Match Code?
· Match Code Object.
· Match Code Id.
What is the max no of match code Id’s that can be defined for one Match code object?
A match code Id is a one character ID that can be a letter or a number.
Can we define our own Match Code ID’s for SAP Matchcodes?
Yes, the number 0 to 9 are reserved for us to create our own Match Code Ids for a SAP defined Matchcode object.
What is an Update type with reference to a Match code ID?
If the data in one of the base tables of a matchcode ID changes, the matchcode data has to be updated. The update type stipulates when the matchcode is to be updated and how it is to be done. The update type also specifies which method is to be used for Building matchcodes. You must specify the update type when you define a matchcode ID.
Can matchcode object contain Ids with different update types?
Yes.
What are the update types possible?
The following update types are possible:
· Update type A: The matchcode data is updated asynchronously to database changes.
· Update type S: The matchcode data is updated synchronously to database changes.
· Update type P: The matchcode data is updated by the application program.
· Update type I: Access to the matchcode data is managed using a database view.
· Update type L: Access to the matchcode is achieved by calling a function module.
What are the two different ways of building a match code object?
A match code can be built in two different ways:
· Logical structure: The matchcode data is set up temporarily at the moment when the match code is accessed. (Update type I, k).
· Physical Structure: The match code data is physically stored in a separate table in the database. (Update type A, S, P).
What are the differences between a Database index and a match code?
· Match code can contain fields from several tables whereas an index can contain fields from only one table.
· Match code objects can be built on transparent tables and pooled and cluster tables.
What is the function of a Domain?
· A domain describes the technical settings of a table field.
· A domain defines a value range, which sets the permissible data values for the fields, which refers to this domain.
· A single domain can be used as basis for any number of fields that are identical in structure.
Can you delete a domain, which is being used by data elements?
No.
What are conversion routines?
· Non-standard conversions from display format to sap internal format and vice-versa are implemented with so called conversion routines.
What is the function of a data element?
A data element describes the role played by a domain in a technical context. A data element contains semantic information.
Can a domain, assigned to a data element be changed?
Yes. We can do so by just overwriting the entry in the field domain.
Can you delete data element, which is being used by table fields.
No.
Can you define a field without a data element?
Yes. If you want to specify no data element and therefore no domain for a field, you can enter data type and field length and a short text directly in the table maintenance.
What are null values?
If the value of a field in a table is undefined or unknown, it is called a null value.
What is the difference between a structure and a table?
Structures are constructed the almost the same way as tables, the only difference using that no database table is generated from them.
What is a view?
A view is a logical view on one or more tables. A view on one or more tables i.e., the data from a view is not actually physically stored instead being derived from one or more tables.
How many types of Views are there?
· Database View
· Help View
· Projection View
· Maintenance View
What is Locking?
When two users simultaneously attempt to access the same data record, this is synchronized by a lock mechanism.
What is database utility?
Database utility is the interface between the ABAP/4 Dictionary and the underlying the SAP system.
What are the basic functions of Database utility?
The basic functions of database utility are:
· Create database objects.
· Delete database objects.
· Adjust database objects to changed ABAP/4 dictionary definition.
What is Repository Info. Systems?
It is a tool with which you can make data stored in the ABAP/4 Dictionary available.
· The external layer.
· The ABAP/4 layer.
· The database layer.
Define external layer?
The external layer is the plane at which the user sees and interacts with the data, that is, the data format in the user interface. This data format is independent of the database system used.
Define ABAP/4 layer?
The ABAP/4 layer describes the data formats used by the ABAP/4 processor.
Define Database layer?
The database layer describes the data formats used in the database.
What is a Data Class?
The Data class determines in which table space the table is stored when it is created in the database.
What is a Size Category?
The Size category describes the probable space requirement of the table in the database.
How many types of size categories and data classes are there?
There are five size categories (0-4) and 11 data classes only three of which are appropriate for application tables:
· APPL0- Master data (data frequently accessed but rarely updated).
· APPL1- Transaction data (data that is changed frequently).
· APPL2- Organizational data (customizing data that is entered when system is configured and then rarely changed).
The other two types are:
· USR
· USR1 – Intended for customer’s own developments.
What are control tables?
The values specified for the size category and data class are mapped to database-specific values via control tables.
What is the function of the transport system and workbench organizer?
The function of the transport system and the Workbench Organizer is to manage any changes made to objects of the ABAP/4 Development Workbench and to transport these changes between different SAP systems.
What is a table pool?
A table pool (or pool) is used to combine several logical tables in the ABAP/4 Dictionary. The definition of a pool consists of at least two key fields and a long argument field (VARDATA).
What are pooled tables?
These are logical tables, which must be assigned to a table pool when they are defined. Pooled tables can be used to store control data (such as screen sequences or program parameters).
What is a table cluster?
A table cluster combines several logical tables in the ABAP/4 Dictionary. Several logical rows from different cluster tables are brought together in a single physical record. The records from the cluster tables assigned to a cluster are thus stored in a single common table in the database.
How can we access the correction and transport system?
Each time you create a new object or change an existing object in the ABAP/4 Dictionary, you branch automatically to the Workbench Organizer or correction and transport system.
Which objects are independent transport objects?
Domains, Data elements, Tables, Technical settings for tables, Secondary indexes for transparent tables, Structures, Views, Matchcode objects, Matchcode Ids, Lock objects.
How is conversion of data types done between ABAP/4 & DB layer?
Conversion between ABAP/4 data types and the database layer is done within the database interface.
How is conversion of data types done between ABAP/4 & external level?
Conversion between the external layer and the ABAP/4 layer is done in the SAP dialog manager DYNP.
What are the Data types of the external layer?
ACCP, Char, CLNT, CUKY, CURR, DATS, DESC, FLTP, INT1, INT2, INT4, LANG, LCHR, LRAW, NUMC, PREC, QUAN, RAW, TIMS, UNIT,VARC.
What are the Data types of the ABAP/4 layer?
Possible ABAP/4 data types:
C: Character.
D: Date, format YYYYMMDD.
F: Floating-point number in DOUBLE PRECISION (8 bytes).
I: Integer.
N: Numerical character string of arbitrary length.
P: Amount of counter field (packed; implementation depends on h/w platform).
S: Time Stamp YYYYMMDDHHMMSS.
V: Character string of variable length, length is given in the first two bytes.
X: Hexadecimal (binary) storage.
How can we set the table spaces and extent sizes?
You can specify the extent sizes and the table space (physical storage area in the database) in which a transparent table is to be stored by setting the size category and data class.
What is the function of the correction system?
The correction system manages changes to internal system components. Such as objects of the ABAP/4 Dictionary.
What are local objects?
Local objects (Dev class$TMP) are independent of correction and transport system.
What is a Development class?
Related objects from the ABAP/4 repository are assigned to the same development class. This enables you to correct and transport related objects as a unit.
What is a data dictionary?
Data Dictionary is a central source of data in a data management system. Its main function is to support the creation and management of data definitions. It has details about
· what data is contained?
· What are the attributes of the data?
· What is the relationship existing between the various data elements?
What functions does a data dictionary perform?
In a data management system, the principal functions performed by the data dictionary are
· Management of data definitions.
· Provision of information for evaluation.
· Support for s/w development.
· Support form documentation.
· Ensuring that the data definitions are flexible and up-to-date.
What are the features of ABAP/4 Dictionary?
The most important features are:
· Integrated to aABAP/4 Development Workbench.
· Active in the runtime environment.
What are the uses of the information in the Data dictionary?
The following information is directly taken from the Data dictionary:
· Information on fields displayed with F1 help.
· Possible entries for fields displayed with F4 help.
· Matchcode and help views search utilities.
What are the basic objects of the data dictionary?
· Tables
· Domains
· Data elements
· Structures
· Foreign Keys
What are the aggregate objects in the data dictionary?
· Views
· Match codes
· Lock objects.
In the ABAP/4 Dictionary Tables can be defined independent of the underlying database (T/F).
True.
ABAP/4 Dictionary contains the Logical definition of the table.
A field containing currency amounts (data type CURR) must be assigned to a reference table and a reference field. Explain.
As a reference table, a system containing all the valid currencies is assigned or any other table, which contains a field with the currency key format. This field is called as reference field. The assignment of the field containing currency amounts to the reference field is made at runtime. The value in the reference field determines the currency of the amount.
A field containing quantity amounts (data type QUAN) must be assigned to a reference table and a reference field. Explain?
As a reference table, a system table containing all the valid quantity units is assigned or any other table, which contains a field with the format or quantity units (data type UNIT). This field is called as reference field.
The assignment of the field containing quantity amounts to the reference field is made at runtime. The value in the reference field determines the quantity unit of the amount.
What is the significance of Technical settings (specified while creating a table in the data dictionary)? By specifying technical settings we can control how database tables are created in the database. The technical settings allows us to
· Optimize storage space requirements.
· Table access behavior.
· Buffering required.
· Changes to entries logged.
What is a Table attribute?
The table’s attributes determine who is responsible for maintaining a table and which types of access are allowed for the table. The most important table attributes are:
· Delivery class.
· Table maintenance allowed.
· Activation type.
What is the significance of Delivery Class?
· The delivery class controls the degree to which the SAP or the customer is responsible for table maintenance.
· Whether SAP provides the table with or without contents.
· Determines the table type.
· Determines how the table behaves when it is first installed, at upgrade, when it is transported, and when a client copy is performed.
What is the max. no. Of structures that can be included in a table or structure.
Nine.
What are two methods of modifying SAP standard tables?
· Append Structures and
· Customizing Includes.
What is the difference between a Substructure and an Append Structure?
· In case of a substructure, the reference originates in the table itself, in the form of a statement include….
· In case of an append structure, the table itself remains unchanged and the reference originates in the append structure.
To how many tables can an append structure be assigned.
One.
If a table that is to be extended contains a long field, we cannot use append structures why?
Long fields in a table must always be located in the end, as the last field of the table. If a table has an append structure the append line must also be on the last field of the table.
Can we include customizing include or an append structure with Pooled or Cluster tables?
No.
What are the two ways for restricting the value range for a domain?
· By specifying fixed values.
· By stipulating a value table.
Structures can contain data only during the runtime of a program (T/F)
True.
What are the aggregate objects in the Dictionary?
· Views
· Match Code.
· Lock Object.
What are base tables of an aggregate object?
The tables making up an aggregate object (primary and secondary) are called aggregate object.
The data of a view is not physically stored, but derived from one or more tables (t/f)
True.
What are the 2 other types of Views, which are not allowed in Release 3.0?
· Structure Views.
· Entity Views.
What is a Match Code?
Match code is a tool to help us to search for data records in the system. Match Codes are an efficient and user-friendly search aid where key of a record is unknown.
What are the two levels in defining a Match Code?
· Match Code Object.
· Match Code Id.
What is the max no of match code Id’s that can be defined for one Match code object?
A match code Id is a one character ID that can be a letter or a number.
Can we define our own Match Code ID’s for SAP Matchcodes?
Yes, the number 0 to 9 are reserved for us to create our own Match Code Ids for a SAP defined Matchcode object.
What is an Update type with reference to a Match code ID?
If the data in one of the base tables of a matchcode ID changes, the matchcode data has to be updated. The update type stipulates when the matchcode is to be updated and how it is to be done. The update type also specifies which method is to be used for Building matchcodes. You must specify the update type when you define a matchcode ID.
Can matchcode object contain Ids with different update types?
Yes.
What are the update types possible?
The following update types are possible:
· Update type A: The matchcode data is updated asynchronously to database changes.
· Update type S: The matchcode data is updated synchronously to database changes.
· Update type P: The matchcode data is updated by the application program.
· Update type I: Access to the matchcode data is managed using a database view.
· Update type L: Access to the matchcode is achieved by calling a function module.
What are the two different ways of building a match code object?
A match code can be built in two different ways:
· Logical structure: The matchcode data is set up temporarily at the moment when the match code is accessed. (Update type I, k).
· Physical Structure: The match code data is physically stored in a separate table in the database. (Update type A, S, P).
What are the differences between a Database index and a match code?
· Match code can contain fields from several tables whereas an index can contain fields from only one table.
· Match code objects can be built on transparent tables and pooled and cluster tables.
What is the function of a Domain?
· A domain describes the technical settings of a table field.
· A domain defines a value range, which sets the permissible data values for the fields, which refers to this domain.
· A single domain can be used as basis for any number of fields that are identical in structure.
Can you delete a domain, which is being used by data elements?
No.
What are conversion routines?
· Non-standard conversions from display format to sap internal format and vice-versa are implemented with so called conversion routines.
What is the function of a data element?
A data element describes the role played by a domain in a technical context. A data element contains semantic information.
Can a domain, assigned to a data element be changed?
Yes. We can do so by just overwriting the entry in the field domain.
Can you delete data element, which is being used by table fields.
No.
Can you define a field without a data element?
Yes. If you want to specify no data element and therefore no domain for a field, you can enter data type and field length and a short text directly in the table maintenance.
What are null values?
If the value of a field in a table is undefined or unknown, it is called a null value.
What is the difference between a structure and a table?
Structures are constructed the almost the same way as tables, the only difference using that no database table is generated from them.
What is a view?
A view is a logical view on one or more tables. A view on one or more tables i.e., the data from a view is not actually physically stored instead being derived from one or more tables.
How many types of Views are there?
· Database View
· Help View
· Projection View
· Maintenance View
What is Locking?
When two users simultaneously attempt to access the same data record, this is synchronized by a lock mechanism.
What is database utility?
Database utility is the interface between the ABAP/4 Dictionary and the underlying the SAP system.
What are the basic functions of Database utility?
The basic functions of database utility are:
· Create database objects.
· Delete database objects.
· Adjust database objects to changed ABAP/4 dictionary definition.
What is Repository Info. Systems?
It is a tool with which you can make data stored in the ABAP/4 Dictionary available.
BDC 1. What is full form of BDC Session?
Batch Data Communication Session.
2. What are the steps in a BDC session?
The first step in a BDC session is to identify the screens of the transaction that the program will process. Next step is to write a program to build the BDC table that will be used to submit the data to SAP. The final step is to submit the BDC table to the system in the batch mode or as a single transaction by the CALL TRANSACTION command.
3. How do you find the information on the current screen?
The information on the current screen can be found by SYSTEM à STATUS command from any menu.
4. How do you save data in BDC tables?
The data in BDC tables is saved by using the field name ‘BDC_OKCODE’ and field value of ‘/11’.
5. What is the last entry in all BDC tables?
In all BDC tables the last entry is to save the data by using the field name BDC_OKCODE and a field value of ‘/11’.
6. What is a multiple line field?
A multiple line field is a special kind of field which allows the user to enter multiple lines of data into it.
7. How do you populate data into a multiple line field?
To populate data into a multiple line field, an index is added to the field name to indicate which line is to be populated by the BDC session (Line index).
8. Write the BDC table structure.
BDC table structure
FIELD TYPE DESCRIPTION
Program CHAR (8) Program name of transaction.
DynPro CHAR (4) Screen number of transaction.
DynBegin CHAR (1) Indicator for new screen.
Fnam CHAR (35) Name of database field from screen.
Fval CHAR (80) Value to submit to field.
9. Does the CALL TRANSACTION method allow multiple transactions to be processed by SAP?
No. The CALL TRANSACTION method allows only a single transaction to be processed by SAP.
10. Does the BDC-INSERT function allow multiple transactions to be processed by SAP?
Yes.
11. What is the syntax for ‘CALL TRANSACTION’?
CALL TRANSACTION trans [using bdctab MODE mode].
Three possible entries are there for MODE.
A - Show all screens.
E - Show only screens with errors.
N - Show no screens.
Batch Data Communication Session.
2. What are the steps in a BDC session?
The first step in a BDC session is to identify the screens of the transaction that the program will process. Next step is to write a program to build the BDC table that will be used to submit the data to SAP. The final step is to submit the BDC table to the system in the batch mode or as a single transaction by the CALL TRANSACTION command.
3. How do you find the information on the current screen?
The information on the current screen can be found by SYSTEM à STATUS command from any menu.
4. How do you save data in BDC tables?
The data in BDC tables is saved by using the field name ‘BDC_OKCODE’ and field value of ‘/11’.
5. What is the last entry in all BDC tables?
In all BDC tables the last entry is to save the data by using the field name BDC_OKCODE and a field value of ‘/11’.
6. What is a multiple line field?
A multiple line field is a special kind of field which allows the user to enter multiple lines of data into it.
7. How do you populate data into a multiple line field?
To populate data into a multiple line field, an index is added to the field name to indicate which line is to be populated by the BDC session (Line index).
8. Write the BDC table structure.
BDC table structure
FIELD TYPE DESCRIPTION
Program CHAR (8) Program name of transaction.
DynPro CHAR (4) Screen number of transaction.
DynBegin CHAR (1) Indicator for new screen.
Fnam CHAR (35) Name of database field from screen.
Fval CHAR (80) Value to submit to field.
9. Does the CALL TRANSACTION method allow multiple transactions to be processed by SAP?
No. The CALL TRANSACTION method allows only a single transaction to be processed by SAP.
10. Does the BDC-INSERT function allow multiple transactions to be processed by SAP?
Yes.
11. What is the syntax for ‘CALL TRANSACTION’?
CALL TRANSACTION trans [using bdctab MODE mode].
Three possible entries are there for MODE.
A - Show all screens.
E - Show only screens with errors.
N - Show no screens.
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Investor FAQ:Company FactsWhen was SAP founded? What products and services does SAP offer? What does the acronym "SAP" stand for? Where can I find information about the SAP Executive Board? What is SAP's current headcount? How much does SAP invest annually in research and development? What is a credit rating? Does SAP have a credit rating? Do SAP employees participate in the company's success? What are the largest competitors of SAP? When will SAP announce its next quarterly figures? Which accounting standard does SAP use for its annual financial statements? In what currency are SAP's results reported? Where can I read current SAP business and financial news? Where can I order SAP's latest annual report? When was SAP founded?In 1972, five former IBM employees founded SAP. Their vision was to develop standard application software for real-time processing.
What products and services does SAP offer?SAP is a world leader in business solutions, offering comprehensive software and services that address the unique needs of customers around the world. More information can be found on the SAP Solutions page.
What does the acronym "SAP" stand for?"SAP" stands for Systems, Applications, and Products in Data Processing.
Where can I find information about the SAP Executive Board?Access the Executive Board page for information about the SAP Executive Board.
What is SAP's current headcount?Reflecting its success, SAP hired many highly qualified professionals during 2006, strengthening its foundation for future success and continued growth. The number of full-time employees grew by 3,482 in 2006. At the end of the year, SAP employed 39,355 people worldwide, of whom 14,214 were located in Germany.
The following table lists full-time-equivalent employees at year end, along with the change since the previous year in percent.
2002 2003 2004 2005 2006 Employees (full-time-equivalents) 28,797 29,610 32,205 35,873 39,355 Growth (year-over-year) 1% 3% 9% 11% 10%
How much does SAP invest annually in research and development?SAP recognizes that it must continuously improve its portfolio of innovative products to maintain its leading position as a vendor of business software. Adjusted R&D expenses grew 19% in 2005 to €1,287 million. The portion of its total revenue that SAP spent (based on the adjusted measure) on R&D in 2006 rose to 14%. Expenses for R&D include employee salaries and costs for externally procured development activities.
The following table lists annual adjusted R&D expenditure, along with the change since the previous year in percent:
2002 2003 2004 2005 2006 Adjusted R&D expenses (in millions of euros) 898 832 900 1,071 1,287 Growth (year-over-year) 4% -7% 8% 19% 20%
What is a credit rating? Does SAP have a credit rating?A credit rating is a qualified assessment and formal evaluation of a company's creditworthiness and capability of repaying outstanding obligations on time. Credit ratings are especially interesting for companies issuing corporate bonds on the capital market in order to gain additional liquidity in the form of debt.
SAP does not have a credit rating from rating agencies such as Standard & Poor's or Moody's because of our sound liquidity situation and minimal debt. In addition, SAP has not issued corporate bonds on the financial market and does not rely on debt capital to finance the company.
Do SAP employees participate in the company's success?SAP offers our employees and managers various investment programs, such as the STAR, LTI, and SOP Plans.
What are the largest competitors of SAP?The main competitors are Microsoft Dynamics and Oracle.
When will SAP announce its next quarterly figures?Announcement dates are listed on our Financial Calendar.
Which accounting standard does SAP use for its annual financial statements?Since fiscal year 1999 the accounts have been prepared with full disclosure in accordance with U.S. Generally Accepted Accounting Principles (U.S. GAAP).
In what currency are SAP's results reported?SAP is a European company, so our results are reported in euros.
Where can I read current SAP business and financial news?Current SAP business and financial news is listed under Financial News and in the Press Room.
Where can I order SAP's latest annual report?You can order annual reports through our Information Order Service.
What products and services does SAP offer?SAP is a world leader in business solutions, offering comprehensive software and services that address the unique needs of customers around the world. More information can be found on the SAP Solutions page.
What does the acronym "SAP" stand for?"SAP" stands for Systems, Applications, and Products in Data Processing.
Where can I find information about the SAP Executive Board?Access the Executive Board page for information about the SAP Executive Board.
What is SAP's current headcount?Reflecting its success, SAP hired many highly qualified professionals during 2006, strengthening its foundation for future success and continued growth. The number of full-time employees grew by 3,482 in 2006. At the end of the year, SAP employed 39,355 people worldwide, of whom 14,214 were located in Germany.
The following table lists full-time-equivalent employees at year end, along with the change since the previous year in percent.
2002 2003 2004 2005 2006 Employees (full-time-equivalents) 28,797 29,610 32,205 35,873 39,355 Growth (year-over-year) 1% 3% 9% 11% 10%
How much does SAP invest annually in research and development?SAP recognizes that it must continuously improve its portfolio of innovative products to maintain its leading position as a vendor of business software. Adjusted R&D expenses grew 19% in 2005 to €1,287 million. The portion of its total revenue that SAP spent (based on the adjusted measure) on R&D in 2006 rose to 14%. Expenses for R&D include employee salaries and costs for externally procured development activities.
The following table lists annual adjusted R&D expenditure, along with the change since the previous year in percent:
2002 2003 2004 2005 2006 Adjusted R&D expenses (in millions of euros) 898 832 900 1,071 1,287 Growth (year-over-year) 4% -7% 8% 19% 20%
What is a credit rating? Does SAP have a credit rating?A credit rating is a qualified assessment and formal evaluation of a company's creditworthiness and capability of repaying outstanding obligations on time. Credit ratings are especially interesting for companies issuing corporate bonds on the capital market in order to gain additional liquidity in the form of debt.
SAP does not have a credit rating from rating agencies such as Standard & Poor's or Moody's because of our sound liquidity situation and minimal debt. In addition, SAP has not issued corporate bonds on the financial market and does not rely on debt capital to finance the company.
Do SAP employees participate in the company's success?SAP offers our employees and managers various investment programs, such as the STAR, LTI, and SOP Plans.
What are the largest competitors of SAP?The main competitors are Microsoft Dynamics and Oracle.
When will SAP announce its next quarterly figures?Announcement dates are listed on our Financial Calendar.
Which accounting standard does SAP use for its annual financial statements?Since fiscal year 1999 the accounts have been prepared with full disclosure in accordance with U.S. Generally Accepted Accounting Principles (U.S. GAAP).
In what currency are SAP's results reported?SAP is a European company, so our results are reported in euros.
Where can I read current SAP business and financial news?Current SAP business and financial news is listed under Financial News and in the Press Room.
Where can I order SAP's latest annual report?You can order annual reports through our Information Order Service.
Taj Mahal
Taj Ma·hal [ tj mə hl ]
noun
Definition:
great Mughal monument: a white marble mausoleum in Agra, northern India, completed in 1643 in memory of Mumtaz Mahal, the wife of Mughal emperor Shah Jahan. It is considered the greatest example of Mughal architecture.
Taj Ma·hal [ tj mə hl ]
noun
Definition:
great Mughal monument: a white marble mausoleum in Agra, northern India, completed in 1643 in memory of Mumtaz Mahal, the wife of Mughal emperor Shah Jahan. It is considered the greatest example of Mughal architecture.
V Torque
For equilibrium, all the horizontal components of the force must cancel one another, and all the vertical components must cancel one another as well. This condition is necessary for equilibrium, but not sufficient. For example, if a person stands a book up on a table and pushes on the book equally hard with one hand in one direction and with the other hand in the other direction, the book will remain motionless if the person’s hands are opposite each other. (The net result is that the book is being squeezed). If, however, one hand is near the top of the book and the other hand near the bottom, a torque is produced, and the book will fall on its side. For equilibrium to exist it is also necessary that the sum of the torques about any axis be zero.
A torque is the product of a force and the perpendicular distance to a turning axis. When a force is applied to a heavy door to open it, the force is exerted perpendicularly to the door and at the greatest distance from the hinges. Thus, a maximum torque is created. If the door were shoved with the same force at a point halfway between handle and hinge, the torque would be only half of its previous magnitude. If the force were applied parallel to the door (that is, edge on), the torque would be zero. For an object to be in equilibrium, the clockwise torques about any axis must be canceled by the counterclockwise torques about that axis. Therefore, one could prove that if the torques cancel for any particular axis, they cancel for all axes.
VI
Newton’s Three Laws of Motion
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Newton’s first law of motion states that if the vector sum of the forces acting on an object is zero, then the object will remain at rest or remain moving at constant velocity. If the force exerted on an object is zero, the object does not necessarily have zero velocity. Without any forces acting on it, including friction, an object in motion will continue to travel at constant velocity.
A
The Second Law
Newton’s second law relates net force and acceleration. A net force on an object will accelerate it—that is, change its velocity. The acceleration will be proportional to the magnitude of the force and in the same direction as the force. The proportionality constant is the mass, m, of the object.
F = maIn the International System of Units (also known as SI, after the initials of Système International), acceleration, a, is measured in meters per second per second. Mass is measured in kilograms; force, F, in newtons. A newton is defined as the force necessary to impart to a mass of 1 kg an acceleration of 1 m/sec/sec; this is equivalent to about 0.2248 lb.
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A massive object will require a greater force for a given acceleration than a small, light object. What is remarkable is that mass, which is a measure of the inertia of an object (inertia is its reluctance to change velocity), is also a measure of the gravitational attraction that the object exerts on other objects. It is surprising and profound that the inertial property and the gravitational property are determined by the same thing. The implication of this phenomenon is that it is impossible to distinguish at a point whether the point is in a gravitational field or in an accelerated frame of reference. Einstein made this one of the cornerstones of his general theory of relativity, which is the currently accepted theory of gravitation.
B
Friction
Friction acts like a force applied in the direction opposite to an object’s velocity. For dry sliding friction, where no lubrication is present, the friction force is almost independent of velocity. Also, the friction force does not depend on the apparent area of contact between an object and the surface upon which it slides. The actual contact area—that is, the area where the microscopic bumps on the object and sliding surface are actually touching each other—is relatively small. As the object moves across the sliding surface, the tiny bumps on the object and sliding surface collide, and force is required to move the bumps past each other. The actual contact area depends on the perpendicular force between the object and sliding surface. Frequently this force is just the weight of the sliding object. If the object is pushed at an angle to the horizontal, however, the downward vertical component of the force will, in effect, add to the weight of the object. The friction force is proportional to the total perpendicular force.
Where friction is present, Newton’s second law is expanded to
The left side of the equation is simply the net effective force. (Acceleration will be constant in the direction of the effective force). When an object moves through a liquid, however, the magnitude of the friction depends on the velocity. For most human-size objects moving in water or air (at subsonic speeds), the resulting friction is proportional to the square of the speed. Newton’s second law then becomes
The proportionality constant, k, is characteristic of the two materials that are sliding past each other, and depends on the area of contact between the two surfaces and the degree of streamlining of the moving object.
C
The Third Law
Newton’s third law of motion states that an object experiences a force because it is interacting with some other object. The force that object 1 exerts on object 2 must be of the same magnitude but in the opposite direction as the force that object 2 exerts on object 1. If, for example, a large adult gently shoves away a child on a skating rink, in addition to the force the adult imparts on the child, the child imparts an equal but oppositely directed force on the adult. Because the mass of the adult is larger, however, the acceleration of the adult will be smaller.
Newton’s third law also requires the conservation of momentum, or the product of mass and velocity. For an isolated system, with no external forces acting on it, the momentum must remain constant. In the example of the adult and child on the skating rink, their initial velocities are zero, and thus the initial momentum of the system is zero. During the interaction, internal forces are at work between adult and child, but net external forces equal zero. Therefore, the momentum of the system must remain zero. After the adult pushes the child away, the product of the large mass and small velocity of the adult must equal the product of the small mass and large velocity of the child. The momenta are equal in magnitude but opposite in direction, thus adding to zero.
Another conserved quantity of great importance is angular (rotational) momentum. The angular momentum of a rotating object depends on its speed of rotation, its mass, and the distance of the mass from the axis. When a skater standing on a friction-free point spins faster and faster, angular momentum is conserved despite the increasing speed. At the start of the spin, the skater’s arms are outstretched. Part of the mass is therefore at a large radius. As the skater’s arms are lowered, thus decreasing their distance from the axis of rotation, the rotational speed must increase in order to maintain constant angular momentum.
Sunday, August 19, 2007
Intro to Climate Change
Scientists agree the Earth's climate is being directly affected by human activity, and for many people around the world, these changes are having negative effects. Records show that 11 of the last 12 years were among the 12 warmest on record worldwide.
The just-released Intergovernmental Panel on Climate Change (IPCC) Summary for Policy Makers — the first volume of the IPCC's 4th Assessment Report — states that scientists are more than 90% confident that human industrial activity is driving global temperature rises. (add your thoughts on the report at RealClimate.org)
Carbon dioxide levels today are nearly 30 percent higher than they were prior to the start of the Industrial Revolution, based on records extending back 650,000 years.
According to NASA, the polar ice cap is now melting at the rate of 9 percent per decade. Arctic ice thickness has decreased 40 percent since the 1960s.
The current pace of sea-level rise is three times the historical rate and appears to be accelerating.
The number of Category 4 and 5 hurricanes has almost doubled in the last 30 years. The IPCC 4th Assessment Report said that this trend would likely continue.
Droughts in the Sahel during the 1970s and 1980s were found to be caused by warmer sea surface temperatures, and the current drought in the Amazon is suspected to be a result of rising ocean temperatures.
Poverty and food insecurity has also been tied to climate variability.
contact us web master
The just-released Intergovernmental Panel on Climate Change (IPCC) Summary for Policy Makers — the first volume of the IPCC's 4th Assessment Report — states that scientists are more than 90% confident that human industrial activity is driving global temperature rises. (add your thoughts on the report at RealClimate.org)
Carbon dioxide levels today are nearly 30 percent higher than they were prior to the start of the Industrial Revolution, based on records extending back 650,000 years.
According to NASA, the polar ice cap is now melting at the rate of 9 percent per decade. Arctic ice thickness has decreased 40 percent since the 1960s.
The current pace of sea-level rise is three times the historical rate and appears to be accelerating.
The number of Category 4 and 5 hurricanes has almost doubled in the last 30 years. The IPCC 4th Assessment Report said that this trend would likely continue.
Droughts in the Sahel during the 1970s and 1980s were found to be caused by warmer sea surface temperatures, and the current drought in the Amazon is suspected to be a result of rising ocean temperatures.
Poverty and food insecurity has also been tied to climate variability.
contact us web master
The Great Game
The British became the major power in the Indian sub-continent after the Treaty of Paris (1763) and had begun to show interest in Afghanistan as early as their 1809 treaty with Shuja Shah. It was the threat of the expanding Russian Empire beginning to push for an advantage in the Afghanistan region that placed pressure on British India, in what became known as the "Great Game". The Great Game set in motion the confrontation of the British and Russian empires — whose spheres of influence moved steadily closer to one another until they met in Afghanistan. It also involved Britain's repeated attempts to impose a puppet government in Kabul. The remainder of the nineteenth century saw greater European involvement in Afghanistan and her surrounding territories and heightened conflict among the ambitious local rulers as Afghanistan's fate played out globally. The debacle of the Afghan civil war left a vacuum in the Hindu Kush area that concerned the British, who were well aware of the many times in history it had been employed as the invasion route to India. In the early decades of the nineteenth century, it became clear to the British that the major threat to their interests in India would not come from the fragmented Afghan empire, the Iranians, or the French, but from the Russians, who had already begun a steady advance southward from the Caucasus. At the same time, the Russians feared permanent British occupation in Central Asia as the British encroached northward, taking the Punjab, Sindh, and Kashmir. The British viewed Russia's absorption of the Caucasus, the Kirghiz and Turkmen lands, the Khanate of Khiva, and the Emirate of Bukhara with equal suspicion as a threat to their interests in the Indian subcontinent. In addition to this rivalry between Britain and Russia, there were two specific reasons for British concern over Russia's intentions. First was the Russian influence at the Iranian court, which prompted the Russians to support Iran in its attempt to take Herat, historically the western gateway to Afghanistan and northern India. In 1837 Iran advanced on Herat with the support and advice of Russian officers. The second immediate reason was the presence in Kabul in 1837 of a Russian agent, Captain P. Vitkevich, who was ostensibly there, as was the British agent Alexander Burnes, for commercial discussions. The British demanded that Dost Mohammad sever all contact with the Iranians and Russians, remove Vitkevich from Kabul, surrender all claims to Peshawar, and respect Peshawar's independence as well as that of Kandahar, which was under the control of his brothers at the time. In return, the British government intimated that it would ask Ranjit Singh to reconcile with the Afghans. When Auckland refused to put the agreement in writing, Dost Mohammad turned his back on the British and began negotiations with Vitkevich. In 1838 Auckland, Ranjit Singh, and Shuja signed an agreement stating that Shuja would regain control of Kabul and Kandahar with the help of the British and Sikhs; he would accept Sikh rule of the former Afghan provinces already controlled by Ranjit Singh, and that Herat would remain independent. In practice, the plan replaced Dost Mohammad with a British figurehead whose autonomy would be as limited as that of other Indian princes. It soon became apparent to the British that Sikh participation — advancing toward Kabul through the Khyber Pass while Shuja and the British advanced through Kandahar — would not be forthcoming. Auckland's plan in the spring of 1838 was for the Sikhs — with British support — to place Shuja on the Afghan throne. By summer's end, however, the plan had changed; now the British alone would impose the pliant Shuja.
The Rise of Dost Mohammad
It was not until 1826 that the energetic Dost Mohammad was able to exert sufficient control over his brothers to take over the throne in Kabul, where he proclaimed himself amir. Dost Mohammad achieved prominence among his brothers through clever use of the support of his mother's Qizilbash tribesmen and his own youthful apprenticeship under his brother, Fateh Khan. Among the many problems he faced was repelling Sikh encroachment on the Pashtun areas east of the Khyber Pass. After working assiduously to establish control and stability in his domains around Kabul, the amir next chose to confront the Sikhs. In 1834 Dost Mohammad defeated an invasion by the former ruler, Shuja Shah, but his absence from Kabul gave the Sikhs the opportunity to expand westward. Ranjit Singh's forces occupied Peshawar, moving from there into territory ruled directly by Kabul. In 1836 Dost Mohammad's forces, under the command of his son Mohammad Akbar Khan, defeated the Sikhs at Jamrud, a post fifteen kilometers west of Peshawar. The Afghan leader did not follow up this triumph by retaking Peshawar, however, but instead contacted Lord Auckland, the new British governor general in India, for help in dealing with the Sikhs. With this letter, Dost Mohammad formally set the stage for British intervention in Afghanistan. At the heart of the Great Game lay the willingness of Britain and Russia to subdue, subvert, or subjugate the small independent states that lay between Russia and British India.
Paper power. A new type of battery resembles a small sheet of paperNew Battery Resembles Paper
By swagat
ScienceNOW Daily News13 August 2007A battery that resembles a small sheet of paper could pave the way for a new generation of extremely flexible, cheap, and environmentally friendly energy sources.
A traditional battery has three key elements: an electrolyte solution made up of positive and negative ions, two electrodes made of different materials between which the ions flow, and a separator membrane through which positive and negative ions pass in opposite directions. Attempts to make batteries less bulky and more flexible have met with limited success, largely because of the challenges of combining these elements into thinner materials. A team of scientists headed by chemist Robert Linhardt, materials scientist Pulickel Ajayan, and engineer Omkaram Nalamasu of Rensselaer Polytechnic Institute in Troy, New York, wondered whether paper might be the answer.
To make the new battery, the researchers dissolved cellulose, a plant material used to make paper, in a liquid salt solution. They then added microscopic carbon nanotubes and let the mixture dry. Those steps yielded a thin film that resembled a piece of paper, which was white on one side and black with nanotubes on the other. To complete the battery, the team soaked the cellulose with a lithium hexafluorophosphate solution and covered the white side of the film with lithium metal. The carbon nanotubes served as one electrode and the lithium metal the other. The solution provided the electrolyte, and the cellulose worked as the spacer.
Each gram of paper produces about 10 milliamps of current at 2 volts, and the researchers were able to use the batteries to power a fan and LED light. Stacking multiple sheets increases the power, the team reports online this week in the Proceedings of the National Academy of Sciences. Unlike other flexible batteries, the paper battery is completely integrated, says Linhardt.
The battery has other advantages. It works in temperatures as high as 150°C and as low as -70°C, it retains the flexibility of paper, and, because it's made from 90% cellulose, it's cheap to manufacture. Its low toxicity also makes it an attractive power source for medical devices such as pacemakers and insulin pumps, Linhardt says.
The initial results are "very encouraging," says electrical engineer Sandipan Pramanik of the University of Alberta in Edmonton, Canada. In addition to medical applications, he thinks the technology will provide a better way to charge cell phones and laptops. Before that happens, however, Pramanik says engineers will have to find a way to manufacture the paper batteries on a large scale.
The 1% Solution
By swagat
ScienceNOW Daily News13 August 2007If humans and chimps are 99% alike genetically, how come we're so different? Scientists have been trying to answer that question for more than 30 years. Now researchers have come up with fresh evidence that the answer lies not in the proteins that genes produce but in the timing and level of gene activity.
In 1975, the late evolutionary biologist Allan Wilson of the University of California, Berkeley, and his then-grad student, Mary-Claire King, published a paper in Science relating that comparison of various proteins and nucleic acids between chimps and humans revealed hardly any differences between the two species. So they proposed that the obvious differences might result from the way genes are regulated. Some support for the assertion has since come from studies of individual genes, such as prodynorphin, an endorphin precursor that is expressed more in humans than other primates (ScienceNOW, 17 November 2005).
Now, a group at Duke University in Durham, North Carolina, has performed the first genome-scale survey of promoter regions, DNA sequences that help determine the timing and activity levels of adjacent genes. Using published genomes of chimps, humans, and, for purposes of comparison, macaques, postdoc Ralph Haygood and colleagues in the lab of Gregory Wray analyzed the promoters for 6280 genes that are present in all three species.
By comparing these sequences with nonfunctional promoter sequences (DNA that by comparison with the chimp and macaque versions appears not to have been influenced by selection forces), they were able to ascertain whether a promoter region had evolved quickly, indicating that the trait to which it is linked is adaptive and therefore favorable in human evolution.
The researchers found that the promoter regions for about 575 human genes--especially genes involved in brain function and nutrition--have undergone this selection and are quite different in humans than in chimps. Just what that entails for gene activity is not known, says Haygood, but it means "evolution has been paying attention to the regulation of these genes."
Of the genes whose promoter regions were most affected by selection in humans, many are involved in neural development, including such things as how the axons of nerve cells are directed to form connections with other nerve cells. Haygood says that's not surprising, given the vast differences in behavior and cognitive ability between chimps and humans. More exciting, in his opinion, is that perhaps more than 100 genes relate to carbohydrate metabolism, particularly glucose metabolism. Haygood says it's possible that shifting from the fruit-based chimp diet to one rich in carbs, in the form of roots and tubers, could have provided humans with the energy needed for brain expansion. The team reported its findings online 12 August in Nature Genetics.
Molecular geneticist Sean Carroll of the University of Wisconsin, Madison, says the study offers some "intriguing leads" on candidate genes to be followed up. "There is an important message here" that changes in regulatory sequences may be important in the evolution of many species, he says.
"What a nice paper," says King, who is now a geneticist at the University of Washington, Seattle. "Allan must be smiling from heaven."
By swagat
ScienceNOW Daily News13 August 2007If humans and chimps are 99% alike genetically, how come we're so different? Scientists have been trying to answer that question for more than 30 years. Now researchers have come up with fresh evidence that the answer lies not in the proteins that genes produce but in the timing and level of gene activity.
In 1975, the late evolutionary biologist Allan Wilson of the University of California, Berkeley, and his then-grad student, Mary-Claire King, published a paper in Science relating that comparison of various proteins and nucleic acids between chimps and humans revealed hardly any differences between the two species. So they proposed that the obvious differences might result from the way genes are regulated. Some support for the assertion has since come from studies of individual genes, such as prodynorphin, an endorphin precursor that is expressed more in humans than other primates (ScienceNOW, 17 November 2005).
Now, a group at Duke University in Durham, North Carolina, has performed the first genome-scale survey of promoter regions, DNA sequences that help determine the timing and activity levels of adjacent genes. Using published genomes of chimps, humans, and, for purposes of comparison, macaques, postdoc Ralph Haygood and colleagues in the lab of Gregory Wray analyzed the promoters for 6280 genes that are present in all three species.
By comparing these sequences with nonfunctional promoter sequences (DNA that by comparison with the chimp and macaque versions appears not to have been influenced by selection forces), they were able to ascertain whether a promoter region had evolved quickly, indicating that the trait to which it is linked is adaptive and therefore favorable in human evolution.
The researchers found that the promoter regions for about 575 human genes--especially genes involved in brain function and nutrition--have undergone this selection and are quite different in humans than in chimps. Just what that entails for gene activity is not known, says Haygood, but it means "evolution has been paying attention to the regulation of these genes."
Of the genes whose promoter regions were most affected by selection in humans, many are involved in neural development, including such things as how the axons of nerve cells are directed to form connections with other nerve cells. Haygood says that's not surprising, given the vast differences in behavior and cognitive ability between chimps and humans. More exciting, in his opinion, is that perhaps more than 100 genes relate to carbohydrate metabolism, particularly glucose metabolism. Haygood says it's possible that shifting from the fruit-based chimp diet to one rich in carbs, in the form of roots and tubers, could have provided humans with the energy needed for brain expansion. The team reported its findings online 12 August in Nature Genetics.
Molecular geneticist Sean Carroll of the University of Wisconsin, Madison, says the study offers some "intriguing leads" on candidate genes to be followed up. "There is an important message here" that changes in regulatory sequences may be important in the evolution of many species, he says.
"What a nice paper," says King, who is now a geneticist at the University of Washington, Seattle. "Allan must be smiling from heaven."
Lifelike? This computer simulation shows inorganic particles in a plasma state self-organizing into a hollow helix structure resembling DNA.From Space Dust to Spacefarers
By swagat
ScienceNOW Daily News14 August 2007Dirt that acts like DNA? Using computer simulations, a team of physicists has shown that it's possible for dustlike particles to divide, replicate, and even evolve. The findings hint at one way that life could have gotten started on Earth, and even the incredible although remote possibility that life--and perhaps intelligence--could exist among the interstellar clouds of outer space.
Conventional wisdom says life in the universe requires carbon and liquid water. With these two simple necessities, life has crept into just about every nook and cranny on Earth, from the scalding waters of deep ocean vents to the underside of Antarctica's icy rocks. As a consequence, scientists looking for extraterrestrial life have based all of their searches and instruments on the existence of carbon and--on Mars, for example--on minerals that only could have formed in the presence of water.
Now comes the prospect that life might be able to evolve in an astoundingly simple fashion. Reporting online in today's issue of the New Journal of Physics, a team from Russia, Germany, and Australia details how computer simulations of molecular dynamics can produce conditions under which evolution appears to begin spontaneously. In their simulations, free-floating molecules begin organizing into a helixlike structure resembling DNA, and as time passes, more stable molecular arrangements begin replacing less-stable versions. The process proceeds, the authors say, because an electrical property called polarization tends to organize the particles and reduce chaos, much like tuning a radio to the proper frequency can produce clear audio from the static. The findings are particularly intriguing, they say, because molecular clouds are common across the universe, such as in vast zones of dust among the stars of the Milky Way.
The research is sound and it suggests "a mechanism whereby organic matter could assemble faster than in previous models," says plasma physicist Mark Koepke of West Virginia University in Morgantown. The shorter time could mean a greater probability that conventional life exists elsewhere in the universe, he says.
However, astrobiologist Margaret Turnbull of the Space Telescope Science Institute in Baltimore, Maryland, cautions against underestimating the critical role that water plays in life. Water is "so fabulous for life" because it shields organic molecules "from the electrical charges that would normally drive them apart." Although the researchers may indeed have found another medium within which complex molecules can interact in sophisticated ways, Turnbull says, it remains to be seen whether the right conditions exist in space for these structures to become "complex enough to seed life on young planets."
Seeding cloud. Seen in ultraviolet light, the red giant star MIRA (bright dot at right) sports a cometlike tail stretching more than 13 light-years.The Star That Thinks It's a Comet
By swagat
NOW Daily News15 August 2007One of the hundreds of billions of stars in the Milky Way seems to be having an identity crisis. New images from NASA's Galaxy Evolution Explorer (GALEX) show the star trailing a tail 13 light-years long, making it look like a gigantic comet. Astronomers think the tail will help them probe the star's evolution over the past 30,000 years, and the discovery raises the possibility that other stars sport such features.
It may seem ordinary, but our local neighborhood of stars actually teems with unusual objects. Take Mira, a relatively cool, older star known as a red giant, which lies 350 light-years away in the constellation Cetus. Astronomers first spotted Mira in 1596 and noted its unusual ability to disappear and reappear every 332 days. Earlier this year, an American team took a closer look at Mira with the GALEX spacecraft, which is in the process of mapping the entire sky as it appears in ultraviolet (UV) light.
The astronomers noticed that one of the images appeared smudged. Further inspection revealed that the star was trailing a tail of material some 13 light-years long--or more than three times the distance between the sun and Proxima Centauri, its nearest neighbor. This is the first time anyone has seen a star with a tail, which spectral analysis reveals comprises mainly carbon, nitrogen, and oxygen molecules--some of the elements necessary for life. The atoms in our bodies could have been produced by a star just like Mira, says astronomer Michael Shara of the American Museum of Natural History in New York City. "We're seeing [the material] implanted across the galaxy right now!"
So why the long tail? Although Mira contains only about as much mass as the sun, its diameter is about 400 times greater, meaning that its gravity has a hard time holding on to its atmosphere. Moreover, Mira's course has been taking it through a relatively dense zone of interstellar space, and its interaction with molecules of gas and dust creates a bow-shock effect, similar to what happens when a bullet or a supersonic aircraft travels through air. Material from the bow shock gets heated by friction and then is whipped around and behind the star. Finally, Mira is streaking across the galaxy at 130 kilometers per second, more than twice as fast as most other stars, the team reports online today in Nature. For reasons not yet fully understood, the tail can be seen only in UV.
Based on Mira's speed and the size of its tail, the star has been sloughing off material for at least 30,000 years, says co-author Christopher Martin, NASA's principal investigator for the GALEX mission. "We believe this record will tell us how stars age over time," Martin told reporters during a teleconference today. Red giants like Mira are quite common, notes Shara, so it's probably not the only comet imposter out there. "There must be lots more of these things" in the galaxy, he says.
Helping hand. Superb fairy-wren "nannies" benefit mothers when they help raise the kids.Bird Nannies Give Mom a Break
By swagat
NOW Daily News16 August 2007Every parent can use a little help now and then, and birds are no exception. Some species even use nannies to feed and care for chicks. These "daycare" babies don't seem to do any better than offspring raised by mom and dad alone do, however, and researchers have struggled to figure out how birds benefit from the assistance. A new study has cracked the mystery: The nannies apparently allow mother birds to save their strength so they can lay eggs later on.
In most bird species, males and females pair up to rear the brood. But about 3% of bird species are cooperative breeders: Only one female in a group lays eggs, and the rest of the adults help feed the chicks. Although several studies have shown that chicks get more to eat when helpers are present, little evidence indicates that they grow faster or have a higher survival rate. These findings have led some researchers to propose that the system benefits the helpers rather than the chicks, perhaps because the helpers receive reciprocal aid if they become breeders later on.
A team led by biologist Andrew Russell of the University of Sheffield, U.K., set out to evaluate the costs and benefits of cooperative breeding in the superb fairy-wren of southeastern Australia. This species can breed in pairs and in groups of about 6 to 12 birds, which allows a comparison between the two strategies. In a study population made up of 68 bird nests, the researchers found that chicks that were raised in groups received 19% more food than those fed by their parents alone. Yet those chicks were no larger. The secret, the team reports in the 17 August issue of Science, was that eggs laid by females in cooperative groups were 5% smaller than those laid by females who bred in pairs, and their yolks had 12% less lipids and 13% less protein. Thus, the chicks started out smaller but caught up because they were fed more.
The researchers surmise that by laying smaller eggs and getting outside help--thus reducing the amount of energy they invested in their offspring--mother superb fairy-wrens enhance their own survival and thus their long-term breeding potential. This conclusion is bolstered by the authors' analysis of data from a neighboring population of the same species, which revealed that females that bred in groups had a 30% lower mortality rate than those that bred in pairs.
Russell and his co-workers "have discovered a hidden reproductive strategy" in breeding females, says Jonathan Wright, a behavioral ecologist at the Norwegian University of Science and Technology in Trondheim. And Ashleigh Griffin, a behavioral ecologist at the University of Edinburgh, U.K., says that the report is "deeply satisfying" because it "clears up a mystery" about cooperative breeding. "There are several species of cooperatively breeding birds where helper numbers or helper effort seems to have negligible effect on offspring survival, and that just didn't make any sense."
Good plumbing. The Texas horned lizard boasts tiny channels (shown in cross section, bottom) that help it stay hydrated.Well, That's One Way to Get a Drink
By swagat
ScienceNOW Daily News17 August 2007In hot deserts, animals must get water any way they can. A new study sheds light on what has to be one of nature's most bizarre adaptations to dry environments: Certain lizards have a network of tiny channels in the spaces between their scales that can suck up water from the ground (or from rain falling on their back) and transport it to their mouth for drinking.
Researchers have suspected for decades that some desert lizards can harvest rainwater through their skin. The Australian thorny devil (Moloch horridus), for example, rubs its belly into the wet sand after a rain. In the 1920s, inquisitive researchers put this lizard in a shallow bowl of water and noticed that its entire body soon looked wet. "The initial thought was that they just took the water in directly through their skin," says Wade Sherbrooke, a biologist at the American Museum of Natural History's Southwestern Research Station in Portal, Arizona. But that turned out to be wrong. Unlike amphibian skin, which lets water through, reptile skin keeps precious water inside the body, Sherbrooke says. So how were the lizards transporting water?
Later research suggested that water somehow traveled along the "scale hinges" in between the lizards' scales. In the new study, Sherbrooke and colleagues at James Cook University in Townsville, Australia, used light and electron microscopes to examine the scale hinges in detail. They discovered that the hinges contain tubelike channels about the width of one or two human hairs, a good size for harnessing capillary forces to draw in water. In thorny devils, the network of hinges covers the entire body and appears to funnel water to an area near the corner of the lizards' mouth, the researchers report in this month's issue of Zoomorphology. They found a similar plumbing system in another rain-harvesting lizard, the Texas horned lizard (Phrynosoma cornutum), but not in seven related lizard species that don't transport water.
"It's a really neat paper," says Kurt Schwenk, an evolutionary biologist at the University of Connecticut in Storrs. "This adds one of the big missing pieces and gets at the mechanism of how this cutaneous water transport works." One remaining puzzle, Schwenk says, is how the lizards keep the water flowing in the right direction. He says both species make repetitive tongue movements that might somehow accomplish this--by moving water into the mouth drop by drop so that more liquid gets sucked up to take its place, for instance--but the details are a mystery.
galactic collision challenges dark matter theories
Split up. The Abell 520 cluster collision ripped apart galaxies from dark matter (blue) and hot gas clouds (magenta). The circles show where astronomers had expected the galaxies to end upGalactic Collision Challenges Dark Matter Theories
By swagat patel
NOW Daily News17 August 2007Astronomer Arthur Eddington's prophetic quote about the universe still holds: It is stranger than we can imagine. And new images from NASA's Chandra X-ray Observatory combined with views from two ground-based optical telescopes have produced one of the biggest cosmic mysteries yet. A collision between giant galactic clusters seems to have separated the galaxies from their dark matter cores. The find threatens to turn current thinking about dark matter on its ear.
Dark matter was first predicted 75 years ago, when astronomers noticed that the Milky Way's stars moved faster than they should given the galaxy's mass. Ever since, scientists have searched for evidence of the mysterious substance, which is thought to compose about 25% of the universe. (Visible matter accounts for only 5%, and the even more mysterious dark energy makes up the rest.) So far, they have only been able to detect dark matter's gravitational influence. Clumps of the stuff seem to pull a galaxy together. So, it comes as a major surprise that the new Chandra and ground images apparently show a giant zone of dark matter and a bunch of galaxies going their separate ways.
The images depict hundreds of galaxies merging into a huge cluster called Abell 520, located about 2.4 billion light-years away. As astronomer Andisheh Mahdavi of the University of Victoria in Canada and colleagues will report in the 20 October issue of The Astrophysical Journal, some of the galaxies have moved as far away as 2 million light-years from their dark matter anchors, far enough that gravity will never bring them back. Perhaps just as incredible, the clouds of hot interstellar gas formerly contained by the galaxies--and superheated by the collision so they glow in x-ray light--seem to have been grabbed by the dark matter instead of being flung into space.
The scene contrasts with that of a similar collision reported a year ago in the bullet cluster (ScienceNOW, 21 August 2006). There, dark matter could be seen clearly holding on to the galaxies, not the gas. Abell 520 suggests that something not yet understood has acted to split the galaxies away from dark matter after the collision. The problem, Mahdavi says, is that computer simulations haven't yet been able to duplicate the effects seen in Abell 520, so for now, the phenomenon remains a complete mystery.
Joshua Barnes of the University of Hawaii, Manoa, agrees: "This sort of separation is not supposed to happen." One possible explanation, Barnes says, is that the configuration is more complex than it appears in the images. Avi Loeb of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, says it's better to wait for new observations before revising ideas of dark matter. Mahdavi's team plans to look at Abell 520 with the Hubble Space Telescope soon in hopes of gleaning further clues.
Tuesday, August 14, 2007
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