النساء أكثر قدرة من الرجال على مواجهة الضغوط النفسية

أوضحت دراسة أجراها أخصائيون نفسيون في ألمانيا أن تعرض الأطفال لضغوط نفسية في بطون أمهاتهم، يزيد من احتمال إصابتهم بالأمراض، مشيرة إلى أن النساء في العادة أكثر قدرة على مواجهة الضغوط النفسية من الرجال.

المزيد، أنقر هنا

Giovanni Schiaparelli's Birthday

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"أسطورة صناعة البرمجيات" بيل جيتس يعتزم مغادرة شركته ميكروسوفت

أعلن مؤسس ورئيس شركة ميكروسوفت العالمية الملياردير بيل جيتس عزمه الاستقالة من شركة البرمجيات التي أسسها و قادها لتصبح اكبر شركة من نوعها على مستوى العالم، بعد أن ترك بصماته على عالم صناعة البرمجيات.

أعلن بيل غيتس أنه سيتفرغ للعمل في مؤسسته الخيرية التي تحمل اسم "مؤسسة بيل وميليندا جيتس". وكانت شركة ميكروسوفت قد قالت إن الخطاب الافتتاحي الذي ألقاه جيتس أمس الأحد في معرض مستهلكي الالكترونات قد يكون الخطاب الأخير له في قيادة الشركة.

مزيد من المعلومات، آنقر هنا

Picture of the Day

Explanation: Dust from curious near-Earth asteroid 3200 Phaethon seems to fall from the constellation Gemini in this fisheye skyview. The composite image was recorded over four December nights (12-15) just last year from Ludanyhalaszi, Hungary. Of course, the streaks are meteor trails from the annual Geminids meteor shower. The work of astronomer Erno Berko, the finished picture combines 113 different frames and captures 123 separate meteors. The Geminids is one of the northern skies most reliably performing meteor showers and did not disappoint last year. Under good conditions some skywatchers reported well over 100 meteors per hour near the December 14/15 peak for the Geminids in 2007. Look up tonight and you might see the 2008 Quadrantids.

January 1 TCP/IP

The new Google logo celebrates a milestone invention leading to the modern Internet.

January 1, 83 TCP/IP

This article gives a more in-depth look at what TCP/IP is. It was established as an ARPANET standard on January 1, 1983.

TCP/IP:
IP - is responsible for moving packet of data from node to node. IP forwards each packet based on a four byte destination address (the IP number). The Internet authorities assign ranges of numbers to different organizations. The organizations assign groups of their numbers to departments. IP operates on gateway machines that move data from department to organization to region and then around the world.

TCP - is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.

Sockets - is a name given to the package of subroutines that provide access to TCP/IP on most systems. (Yale.edu)

There are many layers built ontop of TCP/IP. And another protocol called UDP, which is predominatly used in games and other networking situations where low-latency is required is completely different.

The major layers on top of TCP/IP are:

HTTP: Hyper Text Transfer Protocol (for requesting webpages)
FTP: File Transfer Protocol (for uploading files to websites)
SMTP and POP3: For sending (SMTP) and receiving (POP3) e-mail
IRC: For chatting online

There are also many-non standard protocols built on top of TCP/IP. For instance, AOL Instant Messenger uses a third-party protocol to transfer chat messages between clients!

Picture of the Day

Explanation: This symmetric cloud dubbed the Boomerang Nebula was created by a high-speed wind of gas and dust blowing from an aging central star at speeds of nearly 600,000 kilometers per hour. The rapid expansion has cooled molecules in the nebular gas to about one degree above absolute zero - colder than even the cosmic background radiation - making it the coldest known region in the distant Universe. Shining with light from the central star reflected by dust, the frigid Boomerang Nebula is believed to be a star or stellar system evolving toward the planetary nebula phase. This Hubble image was recorded using polarizing filters (analogous to polariod sunglasses) and color coded by the angle associated with the polarized light. The gorgeous result traces the small dust particles responsible for polarizing and scattering the light. The Boomerang Nebula spans about one light year and lies about 5,000 light years away toward the constellation Centaurus.

http://antwrp.gsfc.nasa.gov/apod/astropix.html