post doc position
星期三, 06月 20th, 2007 请有兴趣的试一试，我觉得有一点计算机基础，尤其懂数据库，有遗传育种的背景知识就可以胜任这个工作！
这个所谓的生物信息学，不是大家通常理解的生物信息学，应该叫应用生物信息学！
Archive for 06月, 2007
本周推荐（4）
星期二, 06月 19th, 2007Stephen J Dinka, Matthew A Campbell, Tyler Demers, and ManishN Raizada Predicting the Size of the Progeny Mapping
Population Required to Positionally Clone a Gene. Genetics
2007; published ahead of print on June 11, 2007 as doi:
10.1534/genetics.107.074377
Population Required to Positionally Clone a Gene. Genetics
2007; published ahead of print on June 11, 2007 as doi:
10.1534/genetics.107.074377
相信很多同学在做基因或者QTL的精细定位和克隆，这里有一个问题其实我一直在思考，那就是：我们在发展二级群体的时候到底要多少单株才合适？其实过去一直处于盲人摸象的阶段，为了能有更大的概率找到目标基因，一般来说都趋向于用更大的群体。
这篇文章，通过理论分析给了一个比较简单的计算公式，比较有指导意义。同时作者还统计分析了目前已经图位克隆的41个水稻基因，用这些数字对公式进行了验证和修正。即便你不做基因的图位克隆，这总结的41篇文献也能够快速补充你基因或QTL图位克隆方面的背景知识（算精练的文献综述），所以鼎立推荐！
同时，最近和李林在合作写一篇文章，比较定位重组频率的QTL（大家或许对这个概念还不熟悉），结果与41个基因的位置比较分析后，非常有意思，两组数据（QTL内，QTL外）的R值（物理距离和遗传距离的比值）在4倍以上。这些结果结合GENETICS文章的结果，能够为我们未来的基因或QTL的精细定位和图位克隆提供极为有价值的信息。大家有兴趣可以与李林讨论，或者等着看我们的文章！
回忆父亲！
星期一, 06月 18th, 2007
临近中午的时候，才知道今天是父亲节。记忆中的父亲，伟大而帅气。形象渐已模糊，相册没有一张可以瞻仰的照片。49岁，还常常被称作为中青年，父亲一直很强壮，记忆里从没有生过病，正是因为这种强壮让他在最后疾病来临的时候总是习惯忍耐。我已经不再痛恨庸医，因为痛恨已只是过去。当时以高中二年级的学术水平天真的以为写在报纸上的肯定都是真的，那些莫名的中药我不知道是加大了还是减轻了父亲的痛苦，但坚强的父亲从来没有抱怨过，我现在可以理解他当时是忍受着多大的痛苦，他乐观向上的精神在今天仍然是我无法超越的伟大。嗜烟如命的父亲，竟然最终坚决的放弃了香烟，而竟然能在烟友不断的诱惑下，而岿然不动。我现在隐隐有些后悔，其实戒烟并不能延长他的生命，而在最后他却要同时与病痛和烟瘾同时作斗争，那是何等的残酷！不管他多么坚强，也无法阻挡死神的脚步。
父亲终究没有与我一起分享幸福，我不知道他是如何定义幸福的，我只知道他一生忙碌中，没有过歇息，甚至没有来得及坐下来与儿子聊聊人生与未来，我知道他心里一定是有期盼的，或许很伟大，或许很微小。在我幼小的心灵里，也从来不知道要与父亲去沟通，或者要去倾听他的建议。或许我一直骄傲的认为，我对伟大理想的追逐是不需要指引的。或许父亲在我小时候作文和日记里无数次出现的背影就是我的指引。
父亲试图为改变我人生命运做过的唯一一次努力仍然记忆在心，他试图游说当时看来好像很有能耐的人，让我初中毕业能进省重点高中而不是县重点高中；父亲用他最奢侈的款待谦恭的伺候着或许能改变我命运的能人。并破天荒里在那个美丽的夜晚与年轻的儿子一起散步，并试图畅谈人生。我已经不记得父亲是如何和我畅谈人生的，但面对3000元钱这个天文数字的费用，我毫不留情的拒绝了父亲的提议。父亲没有坚持，或许3000对他也是一个很大的数字，或许他相信他的儿子！
如果他仍然活在这个世界，我相信他一定会为他当时的决定高兴。父亲对儿子从来没有打骂，对母亲也是如此，尽管他是当时最强壮的男人之一，是少数双手能抱起200来斤重的大石臼的人。对母亲的唠叨，他永远是沉默；在开完我今天看来是永远也开不完的会议后，不管是多么晚，仍然会把母亲留下的重活一一干完。他永远不知道疲倦!
我知道，我也应该很快会成为父亲，我不知道我会不会成为父亲那样的父亲，其实我非常不自信，会在儿子将来的重要人生选择面前，轻易的听从儿子的而不是我的！那是父亲的伟大之处！我无从超越！但我也希望将来能给儿子能留下一个清晰的背影，就象他爷爷留给他儿子一样！
爱你的父亲象爱你自己一样！
Molecular and funtional diversity of maize
星期六, 06月 16th, 2007 这是为一篇关于玉米的大综述（预计秋天或年底能出来）写的其中一章，勉为其难的活干的不漂亮。主要是高度还不够！积淀还不够！
关联分析现在是我的主要工作，主要做两个方面的工作：
1）利用Illumina SNP
芯片做全基因组范围的关联分析（基因组策略）
芯片做全基因组范围的关联分析（基因组策略）
2）针对特定候选基因和性状做关联分析（候选基因策略）
具体内容下面有提到，感兴趣的可以看看！
The
maize genome harbors tremendous phenotypic and molecular diversity.
Two maize lines are on average as diverged from one another as
humans are from chimpanzees (Buckler et al. 2006). Understanding
the useful genetic diversity for crop improvement should speed the
development of new and more adapted
varieties.
maize genome harbors tremendous phenotypic and molecular diversity.
Two maize lines are on average as diverged from one another as
humans are from chimpanzees (Buckler et al. 2006). Understanding
the useful genetic diversity for crop improvement should speed the
development of new and more adapted
varieties.
Molecular markers (especially Restriction Fragment Length
Polymorphism (RFLP) and Single Sequence Repeat (SSR) markers in
past studies, and the more abundant and automatable Single
Nucleotide Polymorphisms (SNPs) more recently) have been used for
genetic diversity studies of maize in the following aspects: (1)
examination of genotype frequencies for deviations at individual
loci (Reif et al. 2004) and characterization of molecular variation
within and/or between populations (Warburton et al. 2002; Reif et
al. 2004); (2) construction of “phylogenetic” trees or
classification of germplasm accessions based on genetic distance
(Warburton et al. 2002; Betrán et al. 2003; Liu et al. 2003; Reif
et al. 2004; Xia et al. 2004; 2005) and determination of heterotic
groups (Warburton et al. 2002; Xia et al. 2004; 2005); (3) analysis
of correlation between the genetic distance and hybrid performance,
heterosis, and special combining ability (Betrán et al. 2003); and
(4) comparison of genetic diversity among different groups of maize
germplasm (Liu et al. 2003; Tarter et al. 2004; Xia et al. 2005).
These studies have provided useful information for breeding,
genebank curation and gene identification.
Several past studies have highlighted the loss of genetic diversity
of the elite temperate maize pool over the past century (Duvick et
al, 2004; Reif et al, 2005). Liu et al (2003) evaluated the genetic
diversity among 260 diverse maize inbred lines with 94 SSR markers
and found that tropical and subtropical inbreds contain a greater
number alleles and gene diversity than temperate inbreds, and that
maize inbreds capture less than 80% of the alleles in the
landraces, suggesting that landraces can provide additional genetic
diversity for maize breeding. However, in another study, Yamasaki
et al (2005) identified 6169 SNPs in 1095 loci of 14 maize inbreds
lines from two distinct gene pools, in order to maximize allelic
diversity. Results indicated that the amount of genetic diversity
contained within the two germplasm pools is similar. The authors
thought this discrepancy may be more apparent than real because of
the different sampling strategies in the two studies. In addition,
unadapted and wild related species containing untapped genetic
resources for biotic and abiotic stress resistance should provide
new alleles for future maize improvement (Hoisington et al., 1999).
Many alleles have been found in the progenitor species of maize,
teosinte, that are not present in maize, by analyzing over one
hundred maize inbreds and teosinte accessions with 462 SSRs
(Vigouroux et al. 2005). Wright et al. (2005) compared SNP
diversity between maize and teosinte in 774 genes that experienced
a much greater reduction of genetic diversity in maize consistent
with artificial selection and crop improvement.
Molecular genetic diversity information has provided a powerful
tool to systematically sample the diversity contained in the
breeding program and gene bank at the International Maize and Wheat
Improvement Center (CIMMYT) and its partners. The markers were used
to construct core subsets, which preserve as much of the diversity
present in the original collection as possible (Franco et al, 2005; 2006). These subsets are being more intensively
characterized at the molecular and genetic level to find new,
functional diversity for maize improvement, for example via
association mapping (described below) and allele mining.
In a recent review, Buckler et al. (2006) summarized three major
approaches being used to evaluate maize functional diversity:
F2-derived QTL mapping, positional cloning, and association
mapping. QTL mapping can map loci that have large effects on a
trait of interest. Examples include QTLs found
for agronomic and yield traits, biotic and abiotic stress traits,
biochemical contents and quality traits (www.maizegdb.org).
Although single genes controlling qualitative traits have been
cloned, few major QTL have been cloned in maize via positional
cloning (Wang et al, 2005).
In contrast to linkage mapping, association mapping (or linkage
disequilibrium mapping) relies on surveys of natural variation.
This approach has been broadly used in human studies especially for
finding genes causing disease susceptibility, but it is being
rapidly adopted in maize (Thornsberry et al, 2001; Palaisa et al.
2003; Wilson et al. 2004; Andersen et al, 2005; Szalma et al, 2005; and Camus-Kulandaivelu et al, 2006) and wheat (Breseghello and
Sorrells, 2006). Many more association mapping projects are now
underway in many plant species and will soon yield
results. Association mapping seeks statistical
correlations between phenotypic variation and changes in candidate
genes sequences (known as the candidate gene approach) or marker
polymorphisms (spread throughout the genome, and known as whole
genome scanning) in a panel of individuals. In plants, this panel
usually consists of a set of inbred or homozygous lines, because it
is easier to measure the effect of each gene when it is in a
homozygous state, but in theory any material can be used. The
material must show variation for the trait or traits of interest,
and must contain a sufficient amount of diversity in general to
present polymorphisms in the sequence of the gene of interest or
the markers to be tested. The more diverse the materials used, the
more likely it is that associated markers will be found to the gene
of interest; however, including material too exotic may find genes
not useful in a breeding program, if that gene works only in
specific genetic backgrounds, or are difficult to phenotype in a
common test environment.
There are several advantages of association mapping compared with
linkage mapping. Association mapping is much faster because there
is no need to create a mapping population. Association mapping may
have a very high resolution, depending on the rate of breakdown of
linkage disequilibrium (LD) in the species being studied. LD is
affected by rate of recombination and mutation, and selection,
inbreeding, and fluxes in population size (Gaut and Long, 2003). In
maize, LD often declines within 1-1.5Kb in landraces and a broad
sample of tropical and temperate inbreds (Tenaillon et al, 2001; Remington et al, 2001), whereas with less rapid decay in elite
breeding materials (Jung et al, 2004). Association mapping in maize
will allow a very high resolution of mapping, but requires the
candidate gene approach, as whole genome scanning would require
hundreds of thousands of markers.
In maize, comprehensive association studies are ongoing in the
group of E. Buckler (http://www.maizegenetics.net/), where
thousands of genes with important functions will be studied in a
broad panel with 288 maize genotypes. CIMMYT currently has two
major association mapping studies ongoing in maize. One study will
focus on a more simply inherited trait, Pro-Vitamin A accumulation
in colored maize kernels that will be studied in the carotenoid
association mapping panel. Another will focus on a very complex
trait, drought tolerance, using more than one hundred drought
related candidate genes and phenotyping in five countries over two
years with 384 broad representational
lines. In addition to association mapping work, the same methods may be
used for allele mining of the diverse subsets of maize being
created from breeder’s lines, genebank accessions, and wild
relatives. Once a gene of interest is positively
identified (via association mapping or any other technique) and the
sequence determined, the same gene can be sequenced in all the
individuals in the subset. New changes in the DNA
sequence, corresponding to new alleles of this locus, will be
identified in this manner, and the new alleles can be measured
phenotypically to determine possible use in future breeding
programs. These alleles may not ever had been found via simple
phenotypic screens, either because it is not possible to grow and
measure every plant in a large germplasm collection under all
possible environmental conditions, or because it’s effect may be
masked in an unsuitable genetic
background. Following successful identification of a gene linked to a trait of
interest, or new alleles of a previously identified gene,
validation must confirm that the results were correct, and that the
allele will be useful in more than one genetic
background. Once a gene is cloned, the use of
transformation to confirm gene function is considered the “gold
standard” in most areas of genetics (Doebley, 2000). However, this
is only one possible validation process, and will not work in every
case (nor in any case where linked markers, but not the gene
itself, was identified). For example, psy1 is an important gene
related with Pro-Vitamin A accumulation which controlled by four
major genes. No obvious phenotypic change can be found if only PSY1
gene is transferred into the target organism. Association studies
of PSY1 gene provide the strong evidence that does control the
kernel color and carotinoid content (Palaisa et al. 2003), but is
only one gene in the pathway and tests other than transformation
must validate the association.
Association mapping can easily be incorporated into ongoing
breeding programs, and will benefit practical breeding by allowing
characterization of different types of germplasm (including
breeding material which will be immediately relevant to the
breeding program, and genebank materials which will contain maximum
diversity and therefore maximum allelic characterization).
Association mapping will identify marker-trait association via
multilocation trials for enhancing Marker Assisted Selection (MAS)
of target traits, and QTL discovery that should be faster than
linkage mapping. In theory, we will see
identification of alleles associated with wide adaptation, and new
alleles of previously identified genes that can be identified in
genebank materials and characterized to determine their relative
value. New alleles positively affecting important agronomic traits
can be backcrossed into elite breeding materials quickly using
markers developed from within the gene itself. These markers
(called functional markers (Andersen and Lübberstedt, 2003)) would
be superior compared to anonymous markers for selection, as there
is no risk of information loss due to recombination between marker
and gene. Association mapping will not replace other methods for
determining marker-gene associations, and may not work in every
case, but it will provide a valuable alternative, and another
method to validate associations found in other analyses or
populations.
Polymorphism (RFLP) and Single Sequence Repeat (SSR) markers in
past studies, and the more abundant and automatable Single
Nucleotide Polymorphisms (SNPs) more recently) have been used for
genetic diversity studies of maize in the following aspects: (1)
examination of genotype frequencies for deviations at individual
loci (Reif et al. 2004) and characterization of molecular variation
within and/or between populations (Warburton et al. 2002; Reif et
al. 2004); (2) construction of “phylogenetic” trees or
classification of germplasm accessions based on genetic distance
(Warburton et al. 2002; Betrán et al. 2003; Liu et al. 2003; Reif
et al. 2004; Xia et al. 2004; 2005) and determination of heterotic
groups (Warburton et al. 2002; Xia et al. 2004; 2005); (3) analysis
of correlation between the genetic distance and hybrid performance,
heterosis, and special combining ability (Betrán et al. 2003); and
(4) comparison of genetic diversity among different groups of maize
germplasm (Liu et al. 2003; Tarter et al. 2004; Xia et al. 2005).
These studies have provided useful information for breeding,
genebank curation and gene identification.
Several past studies have highlighted the loss of genetic diversity
of the elite temperate maize pool over the past century (Duvick et
al, 2004; Reif et al, 2005). Liu et al (2003) evaluated the genetic
diversity among 260 diverse maize inbred lines with 94 SSR markers
and found that tropical and subtropical inbreds contain a greater
number alleles and gene diversity than temperate inbreds, and that
maize inbreds capture less than 80% of the alleles in the
landraces, suggesting that landraces can provide additional genetic
diversity for maize breeding. However, in another study, Yamasaki
et al (2005) identified 6169 SNPs in 1095 loci of 14 maize inbreds
lines from two distinct gene pools, in order to maximize allelic
diversity. Results indicated that the amount of genetic diversity
contained within the two germplasm pools is similar. The authors
thought this discrepancy may be more apparent than real because of
the different sampling strategies in the two studies. In addition,
unadapted and wild related species containing untapped genetic
resources for biotic and abiotic stress resistance should provide
new alleles for future maize improvement (Hoisington et al., 1999).
Many alleles have been found in the progenitor species of maize,
teosinte, that are not present in maize, by analyzing over one
hundred maize inbreds and teosinte accessions with 462 SSRs
(Vigouroux et al. 2005). Wright et al. (2005) compared SNP
diversity between maize and teosinte in 774 genes that experienced
a much greater reduction of genetic diversity in maize consistent
with artificial selection and crop improvement.
Molecular genetic diversity information has provided a powerful
tool to systematically sample the diversity contained in the
breeding program and gene bank at the International Maize and Wheat
Improvement Center (CIMMYT) and its partners. The markers were used
to construct core subsets, which preserve as much of the diversity
present in the original collection as possible (Franco et al, 2005; 2006). These subsets are being more intensively
characterized at the molecular and genetic level to find new,
functional diversity for maize improvement, for example via
association mapping (described below) and allele mining.
In a recent review, Buckler et al. (2006) summarized three major
approaches being used to evaluate maize functional diversity:
F2-derived QTL mapping, positional cloning, and association
mapping. QTL mapping can map loci that have large effects on a
trait of interest. Examples include QTLs found
for agronomic and yield traits, biotic and abiotic stress traits,
biochemical contents and quality traits (www.maizegdb.org).
Although single genes controlling qualitative traits have been
cloned, few major QTL have been cloned in maize via positional
cloning (Wang et al, 2005).
In contrast to linkage mapping, association mapping (or linkage
disequilibrium mapping) relies on surveys of natural variation.
This approach has been broadly used in human studies especially for
finding genes causing disease susceptibility, but it is being
rapidly adopted in maize (Thornsberry et al, 2001; Palaisa et al.
2003; Wilson et al. 2004; Andersen et al, 2005; Szalma et al, 2005; and Camus-Kulandaivelu et al, 2006) and wheat (Breseghello and
Sorrells, 2006). Many more association mapping projects are now
underway in many plant species and will soon yield
results. Association mapping seeks statistical
correlations between phenotypic variation and changes in candidate
genes sequences (known as the candidate gene approach) or marker
polymorphisms (spread throughout the genome, and known as whole
genome scanning) in a panel of individuals. In plants, this panel
usually consists of a set of inbred or homozygous lines, because it
is easier to measure the effect of each gene when it is in a
homozygous state, but in theory any material can be used. The
material must show variation for the trait or traits of interest,
and must contain a sufficient amount of diversity in general to
present polymorphisms in the sequence of the gene of interest or
the markers to be tested. The more diverse the materials used, the
more likely it is that associated markers will be found to the gene
of interest; however, including material too exotic may find genes
not useful in a breeding program, if that gene works only in
specific genetic backgrounds, or are difficult to phenotype in a
common test environment.
There are several advantages of association mapping compared with
linkage mapping. Association mapping is much faster because there
is no need to create a mapping population. Association mapping may
have a very high resolution, depending on the rate of breakdown of
linkage disequilibrium (LD) in the species being studied. LD is
affected by rate of recombination and mutation, and selection,
inbreeding, and fluxes in population size (Gaut and Long, 2003). In
maize, LD often declines within 1-1.5Kb in landraces and a broad
sample of tropical and temperate inbreds (Tenaillon et al, 2001; Remington et al, 2001), whereas with less rapid decay in elite
breeding materials (Jung et al, 2004). Association mapping in maize
will allow a very high resolution of mapping, but requires the
candidate gene approach, as whole genome scanning would require
hundreds of thousands of markers.
In maize, comprehensive association studies are ongoing in the
group of E. Buckler (http://www.maizegenetics.net/), where
thousands of genes with important functions will be studied in a
broad panel with 288 maize genotypes. CIMMYT currently has two
major association mapping studies ongoing in maize. One study will
focus on a more simply inherited trait, Pro-Vitamin A accumulation
in colored maize kernels that will be studied in the carotenoid
association mapping panel. Another will focus on a very complex
trait, drought tolerance, using more than one hundred drought
related candidate genes and phenotyping in five countries over two
years with 384 broad representational
lines. In addition to association mapping work, the same methods may be
used for allele mining of the diverse subsets of maize being
created from breeder’s lines, genebank accessions, and wild
relatives. Once a gene of interest is positively
identified (via association mapping or any other technique) and the
sequence determined, the same gene can be sequenced in all the
individuals in the subset. New changes in the DNA
sequence, corresponding to new alleles of this locus, will be
identified in this manner, and the new alleles can be measured
phenotypically to determine possible use in future breeding
programs. These alleles may not ever had been found via simple
phenotypic screens, either because it is not possible to grow and
measure every plant in a large germplasm collection under all
possible environmental conditions, or because it’s effect may be
masked in an unsuitable genetic
background. Following successful identification of a gene linked to a trait of
interest, or new alleles of a previously identified gene,
validation must confirm that the results were correct, and that the
allele will be useful in more than one genetic
background. Once a gene is cloned, the use of
transformation to confirm gene function is considered the “gold
standard” in most areas of genetics (Doebley, 2000). However, this
is only one possible validation process, and will not work in every
case (nor in any case where linked markers, but not the gene
itself, was identified). For example, psy1 is an important gene
related with Pro-Vitamin A accumulation which controlled by four
major genes. No obvious phenotypic change can be found if only PSY1
gene is transferred into the target organism. Association studies
of PSY1 gene provide the strong evidence that does control the
kernel color and carotinoid content (Palaisa et al. 2003), but is
only one gene in the pathway and tests other than transformation
must validate the association.
Association mapping can easily be incorporated into ongoing
breeding programs, and will benefit practical breeding by allowing
characterization of different types of germplasm (including
breeding material which will be immediately relevant to the
breeding program, and genebank materials which will contain maximum
diversity and therefore maximum allelic characterization).
Association mapping will identify marker-trait association via
multilocation trials for enhancing Marker Assisted Selection (MAS)
of target traits, and QTL discovery that should be faster than
linkage mapping. In theory, we will see
identification of alleles associated with wide adaptation, and new
alleles of previously identified genes that can be identified in
genebank materials and characterized to determine their relative
value. New alleles positively affecting important agronomic traits
can be backcrossed into elite breeding materials quickly using
markers developed from within the gene itself. These markers
(called functional markers (Andersen and Lübberstedt, 2003)) would
be superior compared to anonymous markers for selection, as there
is no risk of information loss due to recombination between marker
and gene. Association mapping will not replace other methods for
determining marker-gene associations, and may not work in every
case, but it will provide a valuable alternative, and another
method to validate associations found in other analyses or
populations.
Reference:
1. Andersen J R, Lübberstedt T. Functional
markers in plants. Trends Plant Sci, 2003, 8: 554-560
2. Andersen J R, Schrag T, Melchinger A E, Zein I,
Lubberstedt T. Validation of Dwarf8 polymorphisms associated with
flowering time in elite european inbred lines of maize (Zea mays
L.). Theor Appl Genet, 2005, 111: 206-217
3. Betrán, F.J., Ribaut, J. M., Beck, D. and
Gonzalez de León, D. Genetic diversity, specific combining
ability, and heterosis in tropical maize under stress and nonstress
environments. Crop Sci, 2003, 43,797-806.
4. Breseghello, F, Sorrels ME. Association mapping
of kernel size and milling quality in wheat (Triticum aestivum L.)
cultivars. Genetics 2006, 172:1165-1177
5. Buckler, E. S., Gaut, B. S. and McMullen, M. D.
(2006) Molecular and functional diversity of maize. Curr. Opin.
Plant Biol. 9, 172-176.
6. Camus-Kulandaivelu L, Veyrieras J-B, Madur D,
Combes V, Fourmann M, Barraud S, Dubreuil P, Gouesnard B, Manicacci
D, Charcosset A. Maize adaptation to temperate climate:
relationship with population structure and polymorphism in the
Dwarf8 gene. Genetics, 2006, 172: 2449-2463
7. Doebley J. A tomato gene weighs in. Science,
2000, 289: 71-72
8. Duvick DN, Smith JSC, Cooper M (2004) Changes
in performance, parentage, and genetic diversity of successful corn
hybrids, 1930–2000. In: Smith CW, Betran J, Runge ECA (eds) Corn:
Origin, History, Technology, and Production. Wiley, New York, pp
65–97
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补记
星期六, 06月 16th, 2007 6月12日是世界无童工日，前天我发现山西奴隶砖厂（还有煤窑）的报道，最小的童工只有8岁！内心最深切的碰撞让我无话可说，繁忙的实验让我暂时忘却这件事情，今天静下来的时候，发现原来铺天盖地的报道都消失了，好象这个事情没有发生过！
引用一段话表达我此时的心情：
山西奴隶工厂，残忍到了我说任何话都显得残忍的地步；残忍到了提任何建议都显得可笑的地步；残忍到了我过着正常生活都显得可耻的地步。
我们需要什么样的富翁
星期五, 06月 15th, 2007 Sanford I.
Weill这次为Cornell大学一次捐了3亿美元，成为这所常青藤大学历史上最大的一笔捐赠。也让我有兴趣去了解一下，这个人到底是谁。查了一下，生于1933年的Weill，1955年从Cornell大学拿到艺术学士学位。一生传奇创业，最后的职位是花旗银行的CEO和董事长，于2006年退休。2004年，福布斯杂志估计他有15亿美元的净资产。1998年，因为他的捐赠，Cornell大学的医学院就以他的名字命名。加上这次捐赠，他累计向Cornell大学捐赠了5亿美元。也就是他吧自己的财富的1/3给了他的母校。我不知道世界上有多少富翁可以做到这一点，更不知道中国有多少富翁可以做到这一点。Wiki（很好的知识介绍网站，好像国内上不了）仅是一些客观冰冷的介绍，我没有时间再去找一些鲜活的幕后新闻来，但我朴素认为这本身就是一个鲜活的新闻。
Weill这次为Cornell大学一次捐了3亿美元，成为这所常青藤大学历史上最大的一笔捐赠。也让我有兴趣去了解一下，这个人到底是谁。查了一下，生于1933年的Weill，1955年从Cornell大学拿到艺术学士学位。一生传奇创业，最后的职位是花旗银行的CEO和董事长，于2006年退休。2004年，福布斯杂志估计他有15亿美元的净资产。1998年，因为他的捐赠，Cornell大学的医学院就以他的名字命名。加上这次捐赠，他累计向Cornell大学捐赠了5亿美元。也就是他吧自己的财富的1/3给了他的母校。我不知道世界上有多少富翁可以做到这一点，更不知道中国有多少富翁可以做到这一点。Wiki（很好的知识介绍网站，好像国内上不了）仅是一些客观冰冷的介绍，我没有时间再去找一些鲜活的幕后新闻来，但我朴素认为这本身就是一个鲜活的新闻。
由他我又想到了世界首富比尔盖茨，不是因为他最有钱，关键是他把自己的大部分金钱用来建立了一个基金会，也因为受益于他的基金会，参与了Harvest-Plus计划项目，并了解了一些关于他的一些传闻。据说，他和夫人到非洲去旅游，发现当地的贫困出乎自己的想像，于是他问自己，我拥有了这么多财富有什么意义呢？世界上还有这么多人还生活在水身火热之中。于是有了世界上最大的基金会，并决定2008年不再担任微软的总裁而潜心经营基金会，并宣称要建立世界上最好的基金会。这样的人是值得尊敬的！
与此同时，在SINA看到一则触目惊心的新闻，山西黑心砖厂奴隶数百名童工，我相信这些黑心老板挣的每个铜板后面都粘有这些童工的血泪，也有理由相信他们会经常在噩梦中醒来而一生不得安宁，当然也包括那些毫不作为的政府帮凶。我们看到的中国富翁如何黑心的新闻多，看到的是一掷千金买某明星拷的羊肉串，一掷万金吃顿什么宴，一掷百万金集体买悍马或者买个8888的汽车号码等等，诸如此类的牛X报道多。却非常少见有哪个富翁卑贱的把自己的名字写在某个大学或者小学的大楼。我相信中国的富翁群体肯定很大，不算那些在国外用大布袋装钱直接去售楼处让外国富翁也目瞪口呆的伪富翁，那些靠自己聪明财智努力挣钱的富翁也不在少数！那为什么社会主义的中国出现不了资本主义国家习以为常的慈善富翁呢？值得思考！
当我们的教育把金钱当作成功的标准后，唯一能引起冷漠目光重新发亮的只有金钱。人们对结果的注重远远超过了对过程带来幸福或者辛酸体验的追求！如果成功只是最后那一刻的耀眼光环的话，那么许多人注定会痛苦一生；如果成功只是那一个实在而飘渺的数字的话，那许多人也注定会痛苦一生，不管你得到这个数字还是没有得到！一个不知道给予，关怀和卑贱的社会注定不是一个成熟的社会，不管你给他灌注一个如何动听的名字！
巨牛的Cornell
星期四, 06月 14th, 2007 我想所有拥有CORNELL信箱的人都收到一封E-mail,Cornell大学刚刚收到一笔高达4.5亿美圆的捐款。
其中的3亿来自Joan and
Sanford I.
Weill.，Weill是Cornell的校友，这也是迄今为止Cornell接受到的最大单笔捐款。还有5000万来自Maurice
R.
Greenberg夫妇和Starr基金会。另外1一个亿捐款者竟然不愿意透露姓名。鉴于Weill的巨大贡献，正在新建的生命科学大楼将被命名为Weill
Hall.这座楼就紧挨着我上班的biotechnology大楼，和其他楼群一样并不起眼，其雄伟程度估计不比农大的新生命科学大楼。
Sanford I.
Weill.，Weill是Cornell的校友，这也是迄今为止Cornell接受到的最大单笔捐款。还有5000万来自Maurice
R.
Greenberg夫妇和Starr基金会。另外1一个亿捐款者竟然不愿意透露姓名。鉴于Weill的巨大贡献，正在新建的生命科学大楼将被命名为Weill
Hall.这座楼就紧挨着我上班的biotechnology大楼，和其他楼群一样并不起眼，其雄伟程度估计不比农大的新生命科学大楼。
包括上面的捐款在内，Cornell一共筹集到16.53亿美圆的资金用于生命科学研究，相信未来几年Cornell将吸引更多的一流科学家来从事生命科学研究！
详细报道参见：
一所能成为历史名校的大学，中的历史不仅仅是时间长，名不仅仅是我们要“建世界一流”的口号。另外还有一个重要的指标就是，他是不是培养了足够牛的学生！能够大笔给钱当然是其中牛学生的一个体现！Cornell牛就牛在，几乎每一座大楼都是以一个人的名字命名，每个名字后面都是沉甸甸的美钞！
让我想起来季羡林先生接受记者采访的一个片段，“你心目中的大学校长是什么样子？”季先生的回答是“会要钱”。我承认，我原先的理解比较的肤浅，我现在的理解是：
1）会向政府各部门或其它企业组织（在中国主要是前者）要钱；中国一般名校的校长基本都具备这个能力，简单说是哭穷的能力！
2）培养足够牛的学生，给学校无条件大笔送钱！（而这确是一个牛校综合实力和办学里念的体现，其效应非一朝一日能显现，中国还显见这样牛的大学和校长）
本周推荐（3）
星期三, 06月 13th, 2007Genetic architecture of complex traits inplants
James B Holland
Current Opinion in Plant Biology 2007, 10:156–161
James B Holland
Current Opinion in Plant Biology 2007, 10:156–161
其实已经给部分同学推荐过这片文章了，我还写过详细的读书笔记！
理由：
1）James B Holland
是分子数量遗传学的权威，有很多新的思想！
是分子数量遗传学的权威，有很多新的思想！
2）本篇综述短小精悍，在说明传统QTL定位不足的情况下，提出了新的见地，当然离不开LD。
3）比较清楚的阐述了NAM（如果不了解这个词的意思，更需要读）的设计思想！
不足的地方：
个人认为，上位性和杂种优势两个小节写的意犹未尽！或许是我期待太高？
如果需要全文，EMAIL给我！
中国玉米进出口打上能源经济烙印(转）
星期二, 06月 12th, 2007|
将于７月２～３日在北京召开的“２００７中国粮油市场展望会”上，中国玉米的进出口问题将是一个重点话题。来自国内相关行业的领军人物将就此发表观点。 中国玉米进出口话题正重新升温 去年三季度我国首次批量进口了美国转基因玉米，引起了市场广泛关注，一时间，关于中国何时将成为玉米净进口国的话题不绝于耳，其中，市场对于中国玉米进出口格局转变的趋势基本取得共识。不过，事态并不如市场预期那般发展。一方面，玉米进口在此之后恢复平静；另一方面，去年四季度开始中国玉米出口重新启动，今年一季度玉米出口总量甚至较去年同期出现了增长。面对如此态势，关于中国玉米进出口的话题正在重新升温。 进出口最终可归为生物燃料问题 从早期历史看，价格低廉是我国玉米出口的主要优势，价格也成为影响玉米出口的主要因素。过去数年，由于国内玉米消费增长快速，带动国内市场供需关系出现变化，使得供需基础这一深层因素对玉米出口的影响日益占据主导地位；在此过程中，供需基础的影响通过生产、消费、供求、价格等市场因素显现出来，并交织在一起，呈现出错综复杂的局面。近两年来，随着能源供应日益紧张，以玉米等为主要原料的替代能源产业发展迅猛，玉米深加工需求大幅增长，在众多市场因素中脱颖而出，成为可能颠覆区域、全国乃至全球市场供需和国际贸易格局的影响因素。玉米进出口最终可以归结为生物燃料和深加工问题。 国内玉米市场供需矛盾初步显现 国家粮油信息中心数据显示，２００３／２００４年度中国玉米工业消费量为１６５０万吨，随后三年的工业消费量分别为２１００万吨、２７５０万吨和３４００万吨，同比增幅分别达到２７．３％、３１％和２３．６％，其中用于酒精加工的玉米消费量增幅分别达到２０％、３３％和２５％。我国自２００１年开始试点发展燃料乙醇产业，初始目的只是消化大量积压的陈化粮，社会意义大于经济意义；发展至今天，这两层意义已经完全换位；在丰厚经济利益、利润前景的带动下，行业内外的大量资金进入燃料乙醇产业。这正是上述高增长率数字背后的现实注释。其结果是国内玉米价格连年走高，出口难度加大，批量进口成为现实，玉米供需矛盾初步显现，甚至由此可能影响到国家粮食安全。在此情形下，２００６年国家首次出台了燃料乙醇“十一五”发展专项规划，在明确继续加快发展生物燃料的同时，确定了以非粮作物为主要原料的发展方向。 中粮加快进军生物能源产业步伐 作为国内粮油行业的传统巨头及生物能源领域的新兴势力，中粮集团近两年的发展动作在一定程度上反映和代表了我国生物能源产业的发展演变过程。２００５年，中粮集团并购中谷集团，进一步巩固了国内粮油行业的霸主地位；这一年开始，中粮集团加快了进军生物能源产业的步伐，相继入主华润生化、吉林燃料乙醇、丰原生化三大燃料乙醇指定生产企业；２００６年，中粮集团正式启动旗下业务的整合行动，重点打造生物能源业务，并成立生化能源事业部，全面负责生化能源业务的战略布局和市场发展。当年，中粮集团在广西建设的国内首个以木薯为原料的燃料乙醇项目正式开工，在河北、辽宁等地规划和投建的燃料乙醇项目也正在顺利展开，这些新项目多以木薯等非粮作物为主要加工原料。上述事件反映了中粮集团在全国范围的战略布局构想和谋划能源市场地位的意图，也折射出其在生物能源加工原料选择上的新思路。其现实背景正是玉米供需关系演变和燃料乙醇发展规划首次出台。 各国玉米市场联动程度大大提高 由能源危机引发的有关玉米供需和进出口的话题不仅在国内市场愈演愈烈，在国际市场同样受到了包括政府在内的多方关注。今年初，美国总统布什发布的生物能源计划提出，到２０１７年时，将全美乙醇和其他替代性燃料的用量提高至３５０亿加仑，这一数字是２００６年５０亿加仑产量的７倍，如果这些乙醇全部用玉米来生产，就美国目前的玉米产量来说，则需要１．５个全美的玉米产量。作为世界头号玉米出口国，美国国内乙醇玉米用量的大幅增长必然引起国际玉米市场的剧烈地震。因而该计划一出，便引起了市场哗然和更多争论。 可以预见，在能源危机日益突出的当今社会，有关玉米供需矛盾的争论必定会长期延续下去。更关键的是，能源危机的全球联动效应正移植到玉米市场，使得各国玉米市场之间的联动程度大大提高，引起各国玉米进出口的连锁变化，从而加速影响甚至重组国际玉米市场贸易格局。 玉米市场新格局酝酿着新的机遇 全球及区域玉米供需关系究竟将如何演变，目前来看，也许很难下一定论；但是不可否认的是，当前玉米市场正处于一个前所未有的发展时期，在深深地打上能源经济的烙印之后，玉米市场很可能呈现出一种有别于传统的面貌、秩序和格局。有鉴于此，国家粮油信息中心即将于今年７月初召开的年度展望论坛已经确定把有关生物能源和玉米进出口的焦点话题作为主要议题之一。值得期待的是，发改委作为国家燃料乙醇发展规划的制定部门、中粮集团作为中国玉米进出口贸易和国内生物能源市场的龙头企业，将分别就上述相关问题作出各自的解读。正如无法轻易断定生物燃料产业发展和玉米供需走向一样，也许人们仍然很难对有关中国玉米进出口的问题作出结论性的答案。不过，机遇始终与挑战并存，新格局酝酿着新机遇，可以肯定，中国玉米市场和进出口贸易将因此寄托着别样的期待。 |