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What Does DNA Evidence Show?

��һ, 03 �� 2007 15:41:04 GMT

What Does DNA Evidence Show?
The recent ability of scientists to determine the structure of human DNA has created an explosion of research involving genetics, disease, evolution, and the origins of human population groups. The study of human origins is facilitated by analysis of DNA that is spared the complexity of the recombination. While most genes can come from either parent, such that the DNA from the parents is recombined in the child, some parts of human DNA are free from recombination. The mitochondria, small energy-producing structures in our cells, contain special DNA that is inherited only from the mother, without recombination with the DNA of the father. Analysis of mitochondrial DNA (mtDNA) shows DNA structures that have been passed along purely maternal lines, from mother to daughter over the generations. Such analysis has proven to be a useful tool for many purposes (Richards and Macaulay, 2001). Likewise, the Y chromosome in men is passed along paternal lines only. Analysis of Y chromosomes can be used to link modern humans to male ancestors. Both mtDNA and Y chromosomes are subject to mutations that occur rarely but with presumably constant rates (the rates depend on what portion of the DNA is being examined--some portions mutate frequently, others remain very steady over time). Groups that share many common mutations can be presumed to be closely related. Groups that have very few common mutations may be presumed to come from family lines that diverged long ago.

The typical human mtDNA molecule is a circular molecule comprising 16569 nucleotides in a specific order. These nucleotides, adenine, guanine, cytosine, and thymine are labeled A, G, C, and T, respectively. An arbitrary position has been defined as nucleotide 1. A standard mtDNA sequence, known as the Cambridge Reference, was the first published human mtDNA sequence (S. Anderson et al., 1981). Mutations can result in a variety of changes, such as a substitution of one nucleotide for another, a deletion of a part of the sequence, or the addition of one or more nucleotides.

Several tools are used in DNA studies. Restriction Fragment Length Polymorphism (RFLP) classified DNA by analysis of patterns in DNA that has been cleaved into chunks by enzymes (restriction endonuclease). If two organisms differ in the distance between sites of cleavage achieved with a particular enzyme, the length of the fragments produced by enzymatic attack will differ. The similarity of the patterns generated can be used to distinguish species. Recent studies employ up to 14 different enzymes that can provide high resolution of differences in portions of human DNA. RFLP is often applied to a highly variable portion of non-coding DNA in the mitochondria called either the control region (CR) or the D-loop.

Direct sequencing of portions of human DNA yields series of nucleotides that allow direct comparison of various genes with those of different individuals. The extensive sequence information can be used to map groups of related individuals into clusters or clades.

Genetic analysis can also be done looking at proteins in the blood, the presence of certain genetic diseases or other genetic traits, and so forth.

Evidence for Asian Origins and Arguments against the Book of Mormon

Studies in the 1980s based on analysis of linguistic, dental, and genetic evidence resulted in the hypothesis that there were three genetic groups in the Americas, the Amerinds, the Na-Denes, and the Aleut-Eskimos, apparently due to three separate migrations of ancestral Asian populations across the Bering Strait. Greenberg et al. (1986) suggested that the first migration (beginning 12,000 years ago) eventually resulted in the spread of Amerind-speakers throughout North, Central, and South America, followed by additional migrations that brought the ancestors of the NaDene-speakers and Aleut-Eskimo speakers into the northern part of the continent. Other early genetic studies supported the three-wave model, while mtDNA studies have pointed to as many as four major waves of migration. But in 1995, a commonly-cited study by Merriwether et al. (1995) argued for a single migration from Mongolia or northern China, based on their review of mtDNA evidence. (See also Kolman et al., 1996.)

A critical fact is that the dominant mtDNA haplogroups in the New World, called haplogroups A, B, C, and D, could all be found in Asia and could very well have originated there. Some have argued that only one migration of a founder population could give rise to all four haplogroups in the New World.

The single-migration view is being eroded in the wake of additional recent studies pointing to multiple migrations. An excellent but very brief summary of recent developments in this area is given by Dillehay (2003 - available online), who notes the growing evidence for multiple migrations (from various Asia and the Pacific rim) and concludes by saying, "Slowly, we are realizing that the ancestry of the Americas is as complex and as difficult to trace as that of other human lineages around the world."

Among genetic studies that challenge single-migration views, Karafet et al. (1999) studied Y-chromosome markers from over 2000 DNA samples from around the world, including 62 Inuit Eskimos, 12 Mixe, 29 Mixtecs, 22 Kazakhs, 30 Evenks, 18 Melanesians, and 54 samples from several tribes in Panama. Fifteen indigenous North Asian groups were also included. Based on analysis of the 95 haplotypes they identified, the authors concluded that there were multiple founder haplotypes that entered the Americas, including the possibility of multiple migrations from a region in Siberia.

In addition to citing Merriwether et al. (1995) to support a single Asiatic migration, Book of Mormon critics are regularly citing a recent article by F.R. Santos et al., "The Central Siberian Origin for Native American Y Chromosomes," American Journal of Human Genetics, Vol. 64, 1999, pp. 619-628, as evidence that the Book of Mormon is wrong. Some of them like this study so much that they have plagiarized the entire article on their Web pages. No need to use a plagiarized copy; use the legal electronic full-text version of Santos et al. (1999) at http://www.journals.uchicago.edu/cgi-bin/resolve?AJHG980542. (The PDF file is at http://www.journals.uchicago.edu/cgi-bin/resolve?AJHG980542PDF.)

The study of Santos et al. (1999) was conducted with a worldwide sample of 306 men. The major Y haplogroup present in most (not all) Native Americans suggested common ancestry with some Siberians, especially the Kets and Altaians from the Yanissey River Basin and the Altai Mountains, respectively. As we will see, this region appears to be one of the best candidates for a major source of New World genes, though other studies point to other parts of Asia.

As always, though, the scope of the study included only a small number of individuals. The 306 men included only a minute sampling of New World genes:

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Domain name registrar

��һ, 03 �� 2007 15:36:16 GMT

Domain name registrar

A domain name registrar is a company accredited by the Internet Corporation for Assigned Names and Numbers (ICANN) and/or by a national ccTLD authority to register Internet domain names. ICANN has authority over gTLDs, or Generic Top Level Domains. Examples of gTLDs include .com, .net and .org. ICANN does not have authority over ccTLDs, or Country Code Top-Level Domains, though it is quite common for domain name registrars to offer ccTLD registration services as well. Most registrars provide DNS hosting service, but this is not required, and is often considered a separate service.

History

Until 1999, there was no Shared Registration System (SRS). Network Solutions (NSI) operated the .com, .net, and .org registries, and was the de jure registrar and registry. However, several companies had set up as de facto registrars, including NetNames, who invented the idea of a commercial standalone domain name registration service in 1996. Registrars formed another link in the food chain, introducing the concept of domain name sales, effectively introducing the wholesale model into the industry. NSI followed suit, forcing the issue of separation of Registry and Registrar. In October 1998, following pressure from the growing domain name registration business and other interested parties, NSI's agreement with the US Department of Commerce was amended, requiring the creation of an SRS that supported multiple registrars. The SRS officially opened on November 30, 1999 under the supervision of ICANN, though there had been several testbed registrars using the system since March 11, 1999. Since then, over 500 registrars have entered the market for domain name registration services.

Designated registrar

An end-user alone, cannot register and manage their domain name information with ICANN. A designated registrar must be chosen to have one's domain names registered and managed with ICANN on their behalf. Prior to 1999, the only .com registrar was NSI, but after the approval of the SRS, this opened up the opportunity for other companies to be designated as registrars.

Only one designated registrar may modify or delete information about a domain name. The competition that SRS created enables the end user to choose from many registrars offering different services at varying prices. It is not unusual for an end user to wish to switch registrars. Thus, there is the domain name transfer clause.

When a registrar registers a .com domain name for the end-user, it must pay a maximum annual fee of US$6.00 to VeriSign and a US$0.25 administration fee to ICANN. VeriSign is the registry manager for .com gTLD. Low cost bulk registrars like Go Daddy and Tucows must manage their margin after paying these fees and their equipment cost. Therefore, the barrier for entry into the bulk registrar industry is high for new companies without an existing customer base.

Domain name transfers

Domain name transfers is the act of designating a new registrar with the authority to add, modify, and delete information about the domain name. The usual process of a domain name transfer is:

The end user contacts the new registrar with the wish to transfer the domain name to their service
The new registrar will contact the old registrar with this information
The old registrar will contact the end user to confirm the authenticity of this request
The old registrar will release authority to the new registrar
The new registrar will notify the end user of transfer completion

After this process, the new registrar becomes one's designated registrar and all correspondence shall be done with them.

Transfer scams

With the introduction of SRS, many smaller registrars had to compete with the de facto standard, NSI. Some companies offered value added services or used viral marketing. Some companies decided to trick customers to switch from NSI - akin to what some phone companies do to get new customers.

Many of these transfer scams involve a notice sent in the mail, fax, or e-mail. Some scammers may even call by phone (as the contact information is available through WHOIS) to harvest more information. These notices would include information publicly available from the WHOIS database to add to the look of authenticity. The text would include legalese to confuse the end user into thinking that it is an official binding document. If one receives such document, one should notify the resident "computer guy" or IT support person.

Scam registrars go after domain names that are expiring soon or have recently expired. Expired domain names do not have to go through the authentication process to be transferred, as the previous registrar would have relinquished management rights of the domain name. Domain name expiry dates are readily available via WHOIS.

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��ڶ�, 14 �� 2007 16:38:38 GMT

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the science that led to DNA in the Special Report

��ڶ�, 14 �� 2007 06:11:01 GMT

Specifically, it was a race between two teams of young scientists working in Britain, as well as the esteemed chemist Linus Pauling, based in California. Already a Nobel laureate, Pauling may have been the favorite, but the discovery would ultimately be made by his British counterparts. Rosalind Franklin and Maurice Wilkins were trying to identify the structure by studying X-ray diffractions of the DNA molecule. But Jim Watson and Francis Crick studied a little bit of everything -- including, to the consternation of some, the work of their competitors. A few have gone so far as to accuse Watson of stealing Franklin's X-ray work. In any case, Waston and Crick's inquisitive working style ultimately allowed them to determine the DNA structure first, in 1953 -- an achievement that led to their Nobel Prize in 1962. Meanwhile, Franklin passed away in 1958 from cancer. Produced/directed by David Glover and edited by Joe Bini. ]]>

About MBA

��ڶ�, 14 �� 2007 05:56:45 GMT

1�� What educational and personal objectives do you hope to satisfy through the MBA program? (Stanford)
2�� What type and level of work do you expect to be engaged in five or ten years now? (Stanford)

3�� Why do you wish to pursue an MBA degree from Harvard Business School? What are your career aspirations and why? (Harvard)

4�� Briefly assess your career progress to date. Elaborate on your future career plans and your motivation for pursuing a graduate degree at Kellogg. (Northwestern)

5�� Briefly assess your career progress to date. How does the MMM program meets your educational needs and career goals? (Northwestern)

6�� Describe how your experiences, both professional and personal, have led to your decision to pursue an MBA at the Wharton School this year. How does this decision relate to your career goals for the future? (Wharton)

7�� What are your short-term and long-term career goals? How will a Columbia Business School MBA helps you achieve these goals? (Columbia)

8�� What are your professional goals? How do your past and present experiences relate to those goals? (Berkeley)

9�� Why are you seeking an MBA or I.M.B.A. from the University of Chicago Graduate School of Business? What do you hope to experience and contribute? What are your plans and goals after you receive your degree? (Chicago)

10. Describe your post-graduation career plans. How will your education, experience, and development to date support those plans? How will an MBA from the University of Michigan Business School help you attain your goals? (Michigan)

11. Why do you wish to pursue the LFM Program and, in particular, the engineering program you selected? (Please be review your application.) How does this fit with your future plans? (MIT)

1�� Discuss a difficult or painful professional experience from which you get valuable lesson. (Stanford)

2�� Describe a setback, disappointment, or occasion of failure that you have experienced. How did you manage the situation, and what did you learn form it? (Harvard)

3�� Discuss a non-academic situation which you were disappointed in yourself. Tell us how it has affected you personally and / or professionally. (Columbia)

4�� If you have ever received a failing grade, been placed on Academic Probation, or been dismissed from any school, please explain. Discuss the circumstances if you attended more than one undergraduate college or began a graduate program that you did not complete. If appropriate, include an explanation of any extraordinary circumstances influencing your academic record. (Chicago)

5�� Describe a failure or setback in your life. How did you overcome this setback? What, if anything, would you do differently if confronted with this situation again? (Michigan)

6�� What is an important lesson that you have learned in life? How did you come to learn this lesson? (MIT)

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Full Time MBA

��ڶ�, 14 �� 2007 05:51:14 GMT

Two-year programs are usually four semesters, spread over two academic years, with a three- or four-month break for an internship. The first year includes core courses required of all MBAs. The second year allows for functional specialization (a specific concentration of study and elective courses).

Students do not work full time during the program; school is considered their first priority.
People often relocate to attend their full-time program of choice.

Company Sponsorship

Employers that sponsor MBA students give up their employees' services for the duration of the program.

A global company might send a candidate for a total immersion experience (including cultural immersion) to another country that represents an important business market.
A consulting firm or investment bank may require employees to earn a master's degree before they can be promoted. Some companies require a full immersion program with the option to return to the company upon completing the MBA. They may offer tuition reimbursement.

Two-Year, Full-Time Advantages

Two-year, full-time programs have several advantages for both career switchers (who change job functions or industries) and career enhancers (who continue in the same job function or industry). These programs provide an opportunity to develop knowledge in a specific discipline, leading to new job skills and prospects. If you are early in your career development, more specialized study may help you to continue in a particular industry or job function and to progress more effectively.

The following are some other advantages.

Academic and Nonacademic Learning

You can customize course work through electives and concentrations.
Two-year programs accept the widest variety of academic backgrounds, usually with the basic requirement that you have an undergraduate degree that meets the business school's standards (usually, this means a four-year college equivalent).
The environment encourages learning far beyond classroom instruction.

Career Enhancement

In an MBA internship, you can learn and practice new skills and enhance your r��sum�� for post-MBA employment.
The summer break allows for further networking in the business world.
You can develop a cohesive network of MBA colleagues, because the entering class takes core courses together.
Full-time programs offer career services (including campus interviews with prospective employers), social and professional clubs (often across industry segments and functional preference), executive speakers' series, career counseling, and other "campus life" services.

Scholarships and Financial Aid

Scholarship money may be available to assist with tuition costs (get information from specific schools).
Loan money is available for eligible full-time students.Two-year, full-time programs can be a wonderful experience for people who have well-defined career goals, are ready to spend an extended period of time out of the workforce, and have the resources to pay for such a program.

If you do not meet this description, a two-year, full-time program may not be for you. It is a very expensive and time-consuming way to explore what you want to do in the future, and a lack of focus can limit the value of what you learn and what you gain from networking opportunities.

Before you consider a two-year, full-time program, you should be confident about what you wish to do in the future and willing to commit the necessary time and resources to furthering these goals.

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Executive MBA

��ڶ�, 14 �� 2007 05:49:29 GMT

Executive MBA (EMBA) programs are geared toward enhancing the careers of working executives, many of whom are company sponsored. These programs are for professionals who are already specialists in a field or industry and need to hone their general management skills to continue up the corporate ladder.

Enrollment is often tied to a new or anticipated promotion.
Students' professional experience and expertise become part of the fabric of the curriculum.
Classes typically meet on Fridays and Saturdays, usually on alternate weekends, over two academic years.
EMBA programs offer full immersion, with learning outside the classroom and extensive faculty and student/team interaction.

EMBA Programs Differ from Full-Time Programs

Because they are fully employed, EMBA students do not hold internships between their first and second years of school.
University scholarships are generally not available for EMBA students, but loan programs such as the Graduate Management Admission Council's MBA LOANS are.
There is limited or no opportunity to specialize. Students all take the same general management curriculum at the same time, rather than core courses one year and electives the next.

Executive MBA Advantages

EMBA programs have several advantages for executives who need career-broadening management training:

They feature a well-constructed curriculum of several courses in each of the major business disciplines.
They usually do not require permanent relocation, making them good for those who can travel virtually anywhere on a regular basis.
EMBAs earn their degree in two years or less, faster than their part-time counterparts.

Executive MBA Limitations

EMBA programs require a high level of commitment from the students, their families, and their employers.

Most EMBA students put in 80 to 100 hours a week between job and school.
Employers must agree to give EMBA students time off from work to attend classes.
Because classroom time can be squeezed into four days per month, absences from class are not tolerated.

In addition, company-sponsored EMBA students generally do not take part in career services activities to avoid a conflict of interest.

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What Does DNA Evidence Show?

Domain name registrar

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the science that led to DNA in the Special Report

About MBA

Full Time MBA

Company Sponsorship

Two-Year, Full-Time Advantages

Academic and Nonacademic Learning

Career Enhancement

Scholarships and Financial Aid

Executive MBA

EMBA Programs Differ from Full-Time Programs

Executive MBA Advantages

Executive MBA Limitations

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