国际基因工程机器大赛高中赛道发展概况

国际基因工程机器大赛(international genetically engineered machine competition,简称iGEM竞赛)是合成生物学国际顶级大学生学术竞赛。iGEM竞赛赛况及项目成果受到Science、Nature、Scientific American、The Economist、英国广播公司(BBC)等顶级学术期刊或国际媒体的关注,具有广泛的国际影响力。吸引了来自世界40多个国家和地区的队伍参赛。2011年起开始有高中队参赛,参赛队伍数量逐年增加,高中生日益成为推动iGEM竞赛及合成生物学发展的重要力量之一,iGEM竞赛也成为培养中学生核心素养的重要平台。基于2017–2021年全球高中队参赛情况,本文总结了高中队赛道规则、选题倾向及获奖情况,进一步分析iGEM竞赛对高中生核心素养培养的意义,探究全球高中参赛队伍的发展趋势,为未来高中参赛队伍建设提供理论参考。     

Toward Reproducible Computational Research: An Empirical Analysis of Data and Code Policy Adoption by Journals

Journal policy on research data and code availability is an important part of the ongoing shift toward publishing reproducible computational science. This article extends the literature by studying journal data sharing policies by year (for both 2011 and 2012) for a referent set of 170 journals. We make a further contribution by evaluating code sharing policies, supplemental materials policies, and open access status for these 170 journals for each of 2011 and 2012. We build a predictive model of open data and code policy adoption as a function of impact factor and publisher and find higher impact journals more likely to have open data and code policies and scientific societies more likely to have open data and code policies than commercial publishers. We also find open data policies tend to lead open code policies, and we find no relationship between open data and code policies and either supplemental material policies or open access journal status. Of the journals in this study, 38% had a data policy, 22% had a code policy, and 66% had a supplemental materials policy as of June 2012. This reflects a striking one year increase of 16% in the number of data policies, a 30% increase in code policies, and a 7% increase in the number of supplemental materials policies. We introduce a new dataset to the community that categorizes data and code sharing, supplemental materials, and open access policies in 2011 and 2012 for these 170 journals.     

Late Prehistoric Settlement Patterns in Southwestern Kansas

Abstract

During the summer of 1975, an intensive archeological site survey was carried out by the University of Kansas in the Cimarron National Grassland, southwestern Kansas, for the U.S. Forest Service. Work focused on the recovery of data to enable the determination of site functions in order to develop a predictive model of prehistoric site locations for the High Plains of western Kansas. Eight functional site types were derived from analysis of recovered stone tools and fauna remains. Analysis of site physiographic data with respect to site functions made it apparent that landform, the availability of water, and raw materials are resources which had statistically significant effect on prehistoric site location strategy in southwestern Kansas. Moreover, for functional site types some physiographic variables are more important than others. It is suggested that the results of this study are applicable to other portions of the High Plains.     

Improvement of thermotolerance in Lachancea thermotolerans using a bacterial selection pressure

The use of thermotolerant yeast strains is an important attribute for a cost-effective high temperature biofermentation processes. However, the availability of thermotolerant yeast strains remains a major challenge. Isolation of temperature resistant strains from extreme environments or the improvements of current strains are two major strategies known to date. We hypothesised that bacteria are potential “hurdles” in the life cycle of yeasts, which could influence the evolution of extreme phenotypes, such as thermotolerance. We subjected a wild-type yeast, Lachancea thermotolerans to six species of bacteria sequentially for several generations. After coevolution, we observed that three replicate lines of yeasts grown in the presence of bacteria grew up to 37 °C whereas the controls run in parallel without bacteria could only grow poorly at 35 °C retaining the ancestral mesophilic trait. In addition to improvement of thermotolerance, our results show that the fermentative ability was also elevated, making the strains more ideal for the alcoholic fermentation process because the overall productivity and ethanol titers per unit volume of substrate consumed during the fermentation process was increased. Our unique method is attractive for the development of thermotolerant strains or to augment the available strain development approaches for high temperature industrial biofermentation.

     

A database for medicinal and aromatic plants of JK (Jammu and Kashmir) in India

High throughput screening of small molecules for a given drug target is achieved using plant materials of medicinal value. Therefore, it is important to document the availability and location of such medicinal plants in the form of a database. Here, we describe a web database containing information (botanical name, common name, local name, botany, chemistry, folklore medicinal use and medicinal uses) about the medicinal and aromatic plants available in JK (Jammu and Kashmir). The database is available for free in public domain.

Availability     

Animal Adoption as Negotiated Order: A Comparison of Open Versus Traditional Shelter Approaches

ABSTRACT

Recently, the sheltering community has begun to reevaluate its adoption policies and the attitudes that shelter workers have towards adopters. Some shelters are now implementing what have been termed “open” adoptions as a way of increasing the number of animals adopted into good homes, moving away from more “traditional,” protective approaches. Based on in-depth interviews with, and observation of, the staff at two such shelters, this study examines how the adoption process is a negotiated order; namely, that workers in concert with each other and potential adopters figure out on a case-by-case basis how to interpret and implement formal adoption policies. Workers at both shelters similarly sorted potential adopters into various categories but relied on different strategies for influencing the outcome of the adoption process.     

Effects of pH and bicarbonate on the nutrient status and growth of three Lupinus species

Aims

High pH, and high bicarbonate (HCO₃⁻) and calcium (Ca) availability characterise calcareous soils. High [Ca] only partially explains why some Lupinus species are calcifuge, so we explored high [HCO₃⁻] and high pH.

Methods

We grew six Lupinus genotypes in hydroponics with pH 5, 6.5 and 8^a (adjusted by KOH), and 8^b (adjusted by KHCO₃). Leaf symptoms and areas, root appearance and biomass were recorded; whole leaf and root nutrient concentrations, and leaf cellular phosphorus (P), Ca and potassium (K) concentrations were determined using elemental X-ray microanalysis.

Results

Chlorosis was observed in young leaves at high pH for L. angustifolius and L. cosentinii, and P deficiency at high pH for all genotypes. High pH decreased iron (Fe) and zinc (Zn) uptake in all genotypes. It also decreased lateral root growth, the uptake of P, K, Ca, and manganese (Mn) by all sensitive species; and translocation of P, Fe, Zn, Mn, and Ca to leaves in most sensitive species. However, leaf [Ca], leaf [K], [K] within each measured cell type, and translocation of K and Ca to leaves of L. pilosus and L. cosentinii at pH 8 were greater than at pH 5 and 6.5. Compared with pH 8^a, all L. angustifolius genotypes translocated more P, Fe, Zn, Mn and K from roots to leaves at pH 8^b. High pH did not affect the leaf cell types that accumulated P and Ca, but decreased the leaf cellular [P].

Conclusions

Lupinus angustifolius and L. cosentinii were sensitive to high [HCO₃⁻] and/or high pH; L. pilosus was relatively tolerant. High pH decreased lateral root growth and nutrient uptake, inhibiting growth of sensitive species. High [HCO₃⁻] diminished the negative effect of pH 8 on nutrient translocation to leaves in most L. angustifolius genotypes. This knowledge provides critical insights into the habits of Lupinus species to guide breeding of calcicole plants.

     

Re-assessment of phosphorus availability in fens with varying contents of iron and calcium

Aim

To further unravel P availability in mineral-rich fens, and test whether high Fe in the soil would lead to low P availability to the vegetation.

Methods

Mesotrophic fens were selected over gradients in Ca and Fe in central Sweden and the Netherlands, to study characteristics of vegetation, pore water and peat soil, including inorganic and organic forms of P, Fe and Al.

Results

Soil Fe was more important than region or soil Ca, and P availability to the vegetation increased from Fe-poor to Fe-rich fens. Contrary to expectations, precipitation of iron phosphates played a minor role in Fe-rich fens. Fe-rich fens were P-rich for three reasons: (1) high P sorption capacity, (2) relatively weak sorption to Fe-OM complexes and (3) high amounts of sorbed organic P, which probably consists of labile P. Also, nonmycorrhizal wetland plants probably especially take up weakly sorbed (organic) P. However, high P did not lead to high biomass or low plant diversity. Fe-rich fens were limited by other nutrients, and high P may help protect the vegetation against Fe-toxicity.

Conclusions

Fe-poor fens are P-poor, irrespective of Ca, and Fe-rich fens P-rich even under mesotrophic conditions. However, high P itself does not endanger Fe-rich fens.

     

Phosphorus and carbon availability regulate structural composition and complexity of AM fungal mycelium

The regulation of the structural composition and complexity of the mycelium of arbuscular mycorrhizal (AM) fungi is not well understood due to their obligate biotrophic nature. The aim of this study was to investigate the structure of extraradical mycelium at high and low availability of carbon (C) to the roots and phosphorus (P) to the fungus. We used monoxenic cultures of the AM fungus Rhizophagus irregularis (formerly Glomus intraradices) with transformed carrot roots as the host in a cultivation system including a root-free compartment into which the extraradical mycelium could grow. We found that high C availability increased hyphal length and spore production and anastomosis formation within individual mycelia. High P availability increased the formation of branched absorbing structures and reduced spore production and the overall length of runner hyphae. The complexity of the mycelium, as indicated by its fractal dimensions, increased with both high C and P availability. The results indicate that low P availability induces a growth pattern that reflects foraging for both P and C. Low C availability to AM roots could still support the explorative development of the mycelium when P availability was low. These findings help us to better understand the development of AM fungi in ecosystems with high P input and/or when plants are subjected to shading, grazing or any management practice that reduces the photosynthetic ability of the plant.     

Comparison of Journal Self-Citation Rates between Some Chinese and Non-Chinese International Journals

Background

The past 3 decades have witnessed a boost in science development in China; in parallel, more and more Chinese scientific journals are indexed by the Journal Citation Reports issued by Thomson Reuters (SCI). Evaluation of the performance of these Chinese SCI journals is necessary and helpful to improve their quality. This study aimed to evaluate these journals by calculating various journal self-citation rates, which are important parameters influencing a journal impact factor.

Methodology/Principal Findings

We defined three journal self-citation rates, and studied these rates for 99 Chinese scientific journals, almost exhausting all Chinese SCI journals currently available. Likewise, we selected 99 non-Chinese international (abbreviated as ‘world’) journals, with each being in the same JCR subject category and having similar impact factors as their Chinese counterparts. Generally, Chinese journals tended to be higher in all the three self-citation rates than world journal counterparts. Particularly, a few Chinese scientific journals had much higher self-citation rates.

Conclusions/Significance

Our results show that generally Chinese scientific journals have higher self-citation rates than those of world journals. Consequently, Chinese scientific journals tend to have lower visibility and are more isolated in the relevant fields. Considering the fact that sciences are rapidly developing in China and so are Chinese scientific journals, we expect that the differences of journal self-citation rates between Chinese and world scientific journals will gradually disappear in the future. Some suggestions to solve the problems are presented.     

Children’s book series and associated curricula support elementary education and outreach in water resources

Background: Water resources are of fundamental importance to society, and are better managed by stakeholders who understand resource issues. Gaining such knowledge is a lifelong process best begun at an early age and best supported by educational approaches integrating across science, technology, engineering and mathematics (STEM). Research scientists can bring resource education to young audiences through children’s books and curricula that emphasise and integrate across STEM principals.

Aims: To encourage empathy for the environment in younger students, researchers at the Niwot Ridge Long Term Ecological Research site have developed a children’s book series and methods for training teachers in water science education.

Methods: Children’s books in the My Water series are paired with curricula, hands-on learning kits, teacher development training and dissemination of materials through school districts to further water science education.

Results: Thousands of children and educators have received training through the My Water book series, and a more broadly focused, federally funded Schoolyard Children’s Book Series has grown out of these efforts towards water resource education.

Conclusions: Children’s books and curricula that integrate STEM principals can play a key role in the development of environmental empathy and lifelong learning to support resource management.     

Implementation science in resource-poor countries and communities

Background

Implementation science in resource-poor countries and communities is arguably more important than implementation science in resource-rich settings, because resource poverty requires novel solutions to ensure that research results are translated into routine practice and benefit the largest possible number of people.

Methods

We reviewed the role of resources in the extant implementation science frameworks and literature. We analyzed opportunities for implementation science in resource-poor countries and communities, as well as threats to the realization of these opportunities.

Results

Many of the frameworks that provide theoretical guidance for implementation science view resources as contextual factors that are important to (i) predict the feasibility of implementation of research results in routine practice, (ii) explain implementation success and failure, (iii) adapt novel evidence-based practices to local constraints, and (iv) design the implementation process to account for local constraints. Implementation science for resource-poor settings shifts this view from “resources as context” to “resources as primary research object.” We find a growing body of implementation research aiming to discover and test novel approaches to generate resources for the delivery of evidence-based practice in routine care, including approaches to create higher-skilled health workers—through tele-education and telemedicine, freeing up higher-skilled health workers—through task-shifting and new technologies and models of care, and increasing laboratory capacity through new technologies and the availability of medicines through supply chain innovations. In contrast, only few studies have investigated approaches to change the behavior and utilization of healthcare resources in resource-poor settings. We identify three specific opportunities for implementation science in resource-poor settings. First, intervention and methods innovations thrive under constraints. Second, reverse innovation transferring novel approaches from resource-poor to research-rich settings will gain in importance. Third, policy makers in resource-poor countries tend to be open for close collaboration with scientists in implementation research projects aimed at informing national and local policy.

Conclusions

Implementation science in resource-poor countries and communities offers important opportunities for future discoveries and reverse innovation. To harness this potential, funders need to strongly support research projects in resource-poor settings, as well as the training of the next generation of implementation scientists working on new ways to create healthcare resources where they lack most and to ensure that those resources are utilized to deliver care that is based on the latest research results.

     

Emerging journals. The benefits of and challenges for publishing scientific journals in and by emerging countries

Emerging countries have established national scientific journals as an alternative publication route for their researchers. However, these journals eventually need to catch up to international standards.Since the first scientific journal was founded—The Philosophical Transactions of the Royal Society in 1665—the number of journals dedicated to publishing academic research has literally exploded. The Thomson Reuters Web of Knowledge database alone—which represents far less than the total number of academic journals—includes more than 11,000 journals from non-profit, society and commercial publishers, published in numerous languages and with content ranging from the natural sciences to the social sciences and humanities. Notwithstanding the sheer scale and diversity of academic publishing, however, there is a difference between the publishing enterprise in developed countries and emerging countries in terms of the commercial rationale behind the journals.…‘national'' or even ‘local'' journals are published and supported because they report important, practical information that would be declined by international journals…Although all academic journals seek to serve their readership by publishing the highest quality and most interesting advances, a growing trend in the twentieth century has also seen publishers in developed countries viewing academic publishing as a way of generating profit, and the desire of journal editors to publish the best and most interesting science thereby serves the commercial interest of publishers who want people to buy the publication.In emerging countries, however, there are few commercial reasons to publish a journal. Instead, ‘national'' or even ‘local'' journals are published and supported because they report important, practical information that would be declined by international journals, either because the topic is of only local or marginal interest, or because the research does not meet the high standards for publication at an international level. Consequently, most ‘national'' journals are not able to finance themselves and depend on public funding. In Brazil, for instance, the national journals account for one-third of the publications of all scientific articles from Brazil and are mostly funded by the government. Other emerging countries that invest in research—notably China, India and Russia—also have a sizable number of national journals, most of which are published in their native language.There is little competition between developed countries to publish the most or the best scientific journals. There is clear competition between the top-flight journals—Nature and Science, for example—but this competition is academically and/or commercially, rather than nationally, based. In fact, countries with similar scientific calibres in terms of the research they generate, differ greatly in terms of the number of journals published within their borders. According to the Thomson Reuters database, for example, the Netherlands, Switzerland and Sweden published 847, 202 and 30 scientific journal, respectively, in 2010—the Netherlands has been a traditional haven for publishers. However, the number of articles published by researchers in these countries in journals indexed by Thomson Reuters—a rough measurement of scientific productivity—does not differ significantly.To overcome the perceived dominance of international journals […] some emerging countries have increased the number of national journalsScientists who edit directly or serve on the editorial boards of high-quality, international journals have a major responsibility because they guide the direction and set the standards of scientific research. In deciding what to publish, they define the quality of research, promote emerging research areas and set the criteria by which research is judged to be new and exciting; they are the gatekeepers of science. The distribution of these scientists also reflects the division between developed and emerging countries in scientific publishing. Using the Netherlands, Switzerland and Sweden as examples, they respectively contributed 235, 256 and 160 scientists to the editorial teams or boards of 220 high-impact, selected journals in 2005 (Braun & Diospatonyi, 2005). These numbers are comparable with the scientific production of these countries in terms of publications. On the other hand, Brazil, South Korea and Russia, countries as scientifically productive in terms of total number of articles as the Netherlands, Switzerland and Sweden, contributed only 28, 29 and 55 ‘gatekeepers'', respectively. A principal reason for this difference is, of course, the more variable quality of the science produced in emerging countries, but it is nevertheless clear that their scientists are under-represented on the teams that define the course and standards of scientific research.To overcome the perceived dominance of international journals, and to address the significant barriers to getting published that their scientists face, some emerging countries have increased the number of national journals (Sumathipala et al, 2004). Such barriers have been well documented and include poor written English and the generally lower or more variable quality of the science produced in emerging countries. However, although English, which is the lingua franca of modern science (Meneghini & Packer, 2007), is not as great a barrier as some would claim, there is some evidence of a conscious or subconscious bias among reviewers and editors in judging articles from emerging countries. (Meneghini et al, 2008; Sumathipala et al, 2004).A third pressure has also forced some emerging countries to introduce more national journals in which to publish academic research from within their borders: greater scientific output. During the past two or three decades, several of these countries have made huge investments into research—notably China, India and Brazil, among others—which has enormously increased their scientific productivity. Initially, the new national journals aspired to adopt the rigid rules of peer review and the quality standards of international journals, but this approach did not produce satisfactory results in terms of the quality of papers published. On the one hand, it is hard for national journals to secure the expertise of scientists competent to review their submissions; on the other, the reviewers who do agree tend to be more lenient, ostensibly believing that peer review as rigorous as that of international journals would run counter to the purpose of making scientific results publicly available, at least on the national level.The establishment of national journals has, in effect, created two parallel communication streams for scientists in emerging countries: publication in international journals—the selective route—and publication in national journals—the regional route. On the basis of their perceived chances to be accepted by an international journal, authors can choose the route that gives them the best opportunity to make their results public. Economic conditions are also important as the resources to produce national journals come from government, so national journals can face budget cuts in times of austerity. In the worst case, this can lead to the demise of national journals to the disadvantage of authors who have built their careers by publishing in them.…to not publish, for any reason, is to break the process of science and potentially inhibit progressThere is some anecdotal evidence that authors who often or almost exclusively publish in international journals hold national journals in some contempt—they regard them as a way of avoiding the effort and hassle of publishing internationally. Moreover, although the way in which governments regard and support the divergent routes varies between countries, in general, scientists who endure and succeed through the selective route often receive more prestige and have more influence in shaping national science policies. Conversely, authors who choose the regional publication route regard their efforts as an important contribution to the dissemination of information generated by the national scientific community, which might otherwise remain locked away—by either language or access policies. Either way, it is worth mentioning that publication is obviously not the end point of a scientific discovery: the results should feed into the pool of knowledge and might inspire other researchers to pursue new avenues or devise new experiments. Hence, to not publish, for any reason, is to break the process of science and potentially inhibit progress.The choice of pursuing publication in regional or international journals also has direct consequences for the research being published. The selective, international route ensures greater visibility, especially if the paper is published in a high-impact journal. The regional route also makes the results and experiments public, but it fails to attract international visibility, in particular if the research is not published in English.It seems that, for the foreseeable future, this scenario will not change. If it is to change, however, then the revolution must be driven by the national journals. In fact, a change that raises the quality and value of national journals would be prudent because it would give scientists from emerging countries the opportunity to sit on the editorial boards of, or referee for, the resulting high-quality national journals. In this way, the importance of national journals would be enhanced and scientists from emerging countries would invest effort and gain experience in serving as editors or referees.The regional route has various weaknesses, however, the most important of which is the peer-review process. Peer-review at national journals is simply of a lower standard owing to several factors that include a lack of training in objective research assessment, greater leniency and tolerance of poor-quality science, and an unwillingness by top researchers to participate because they prefer to give their time to the selective journals. This creates an awkward situation: on the one hand, the inability to properly assess submissions, and on the other hand, a lack of motivation to do so.Notwithstanding these difficulties, most editors and authors of national journals hope that their publications will ultimately be recognized as visible, reliable sources of information, and not only as instruments to communicate national research to the public. In other words, their aspiration is not only to publish good science—albeit of lesser interest to international journals—but also to attain the second or third quartiles of impact factors in their areas. These journals should eventually be good enough to compete with the international ones, mitigating their national character and attracting authors from other countries.The key is to raise the assessment procedures at national journals to international standards, and to professionalize their operations. Both goals are interdependent. The vast majority of national journals are published by societies and research organizations and their editorial structures are often limited to local researchers. As a result, they are shoestring operations that lack proper administrative support and international input, and can come across as amateurish. The SciELO (Scientific Electronic Library Online), which indexes national journals and measures their quality, can require certain changes when it indexes a journal, including the requirement to internationalize the editorial body or board.…experienced international editors should be brought in to strengthen national journals, raise their quality and educate local editors…In terms of improving this status quo, a range of other changes could be introduced. First, more decision-making authority should be given to publishers to decide how to structure the editorial body. The choice of ad hoc assistants—that is, professional scientists who can lend expertise at the editorial level should be selected by the editors—who should also assess journal performance. Moreover, publishers should try to attract international scientists with editorial experience to join a core group of two or three chief or senior editors. Their English skills, their experience in their research field and their influence in the community would catalyse a rapid improvement of the journals and their quality. In other words, experienced international editors should be brought in to strengthen national journals, raise their quality and educate local editors with the long-term objective to join the international scientific editing community. It would eventually merge the national and the selective routes of publishing into a single international route of scientific communication.Of course, there is a long way to go. The problem is that many societies and organizations do not have sufficient resources—money or experience—to attract international scientists as editors. However, new publishing and financial models could provide incentives to attract this kind of expertise. Ultimately, relying on government money alone is neither a reliable nor sufficient source of income to make national journals successful. One way of enhancing revenue streams might be to switch to an open-access model that would charge author fees that could be reinvested to improve the journals. In Brazil, for instance, almost all journals have adopted the open access model (Hedlund et al, 2004). The author fees—around US$1,250—if adopted, would provide financial support for increasing the quality and performance of the journals. Moreover, increased competition between journals at a national level should create a more dynamic and competitive situation among journals, raising the general quality of the science they publish. This would also feed back to the scientific community and help to raise the general standards of science in emerging countries.     

Impact of relative humidity and water availability on the life history of the predatory mite Amblyseius swirskii

The predatory mite Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) is currently used as an efficient biological control agent of thrips, whiteflies and spider mites, which are economically damaging pests of ornamental plants and vegetable crops grown in greenhouses and fields worldwide. Currently, the effects of relative humidity (RH) and water availability on the optimal growth of A. swirskii are unknown. Here, we test the combined effects of different levels of RH (33%, 53%, 73% and 92%) and water availability on the development and reproduction of male and female A. swirskii feeding on the dried fruit mite, Carpoglyphus lactis (Linnaeus). While eggs failed to hatch at 33% RH, the survival rates of the immature stages at?≥?53% RH increased solely in response to water availability and not due to changes in RH. Regarding growth and development, low RH extended the egg–adult duration and pre-oviposition period. We also found that the negative effects of low RH on fecundity were partially or completely eliminated when drinking water was available. For the life table parameters, the highest values of net reproductive rate (R₀) and intrinsic rate of natural increase (r) were achieved at the highest RH and when drinking water was available. Overall, water availability mitigated the negative effect of low RH on female reproduction, and female development was more sensitive to water availability than male development. Lastly, a comparison of similar research on A. swirskii suggested that water availability and RH are more influential on r than food source or temperature.

     

政府补偿与监管机制改革对公立医疗卫生机构科教与学科建设的影响分析

目的 分析政府补偿与监管机制改革对公立医疗卫生机构教学、科研以及学科建设的影响。方法 通过对上海市闵行区的机构调查,收集并分析2008—2012年3所公立综合性医院和12家社区卫生服务中心的医学教育、科研项目、论文发表及重点学科建设状况的相关数据。结果 闵行区公立综合性医院和社区卫生服务中心的医学教育和科研能力有所提升,重点学科建设也有所加强;但仍然存在教学能力薄弱,科研水平层次偏低,缺乏高质量的重点学科等问题。结论 政府补偿与监管机制改革在一定程度上强化了公立医疗机构的医学教育、科研能力和学科建设,但未来需进一步加大对科教和学科建设的鼓励和支持力度。     

Partitioning of Sugar between Growth and Nitrate Reduction in Cotton Roots

The level of endogenous sugars was inversely related to nitrate availability in young cotton (Gossypium hirsutum L.) plants, with high nitrate causing a greater decline in sugar content of roots than of shoots. High nitrate (low sugar) plants also displayed relatively more shoot growth and less root growth than low nitrate (high sugar) plants. These data are consistent with the theory that roots are poor competitors for sugar, and that sugar supply is a major factor limiting root growth in vivo.

The effects of endogenous sugar level on root growth and on nitrate reductase activity in the root were different. When root sugar level was experimentally controlled by varying nitrate concentration in the nutrient solution, root growth was less sensitive than nitrate reductase activity to sugar deficiency. Also, in sterile root tips cultured on media containing a wide range of sucrose concentrations, growth rate was considerably less sensitive to endogenous sugar deficiency than was nitrate assimilation rate. Similarly, in plants which were detopped or girdled, nitrate reductase activity in the roots declined more rapidly than did root sugars, especially glucose and fructose. These results suggest that when sugar is deficient, cotton roots preferentially use it for growth at the expense of nitrate reduction.

     

Big,small or mezzo?

Lessons from science studies for the ongoing debate about ‘big'' versus ‘little'' research projectsDuring the past six decades, the importance of scientific research to the developed world and the daily lives of its citizens has led many industrialized countries to rebrand themselves as ‘knowledge-based economies''. The increasing role of science as a main driver of innovation and economic growth has also changed the nature of research itself. Starting with the physical sciences, recent decades have seen academic research increasingly conducted in the form of large, expensive and collaborative ‘big science'' projects that often involve multidisciplinary, multinational teams of scientists, engineers and other experts.Although laboratory biology was late to join the big science trend, there has nevertheless been a remarkable increase in the number, scope and complexity of research collaborations…Although laboratory biology was late to join the big science trend, there has nevertheless been a remarkable increase in the number, scope and complexity of research collaborations and projects involving biologists over the past two decades (Parker et al, 2010). The Human Genome Project (HGP) is arguably the most well known of these and attracted serious scientific, public and government attention to ‘big biology''. Initial exchanges were polarized and often polemic, as proponents of the HGP applauded the advent of big biology and argued that it would produce results unattainable through other means (Hood, 1990). Critics highlighted the negative consequences of massive-scale research, including the industrialization, bureaucratization and politicization of research (Rechsteiner, 1990). They also suggested that it was not suited to generating knowledge at all; Nobel laureate Sydney Brenner joked that sequencing was so boring it should be done by prisoners: “the more heinous the crime, the bigger the chromosome they would have to decipher” (Roberts, 2001).A recent Opinion in EMBO reports summarized the arguments against “the creeping hegemony” of ‘big science'' over ‘little science'' in biomedical research. First, many large research projects are of questionable scientific and practical value. Second, big science transfers the control of research topics and goals to bureaucrats, when decisions about research should be primarily driven by the scientific community (Petsko, 2009). Gregory Petsko makes a valid point in his Opinion about wasteful research projects and raises the important question of how research goals should be set and by whom. Here, we contextualize Petsko''s arguments by drawing on the history and sociology of science to expound the drawbacks and benefits of big science. We then advance an alternative to the current antipodes of ‘big'' and ‘little'' biology, which offers some of the benefits and avoids some of the adverse consequences.Big science is not a recent development. Among the first large, collaborative research projects were the Manhattan Project to develop the atomic bomb, and efforts to decipher German codes during the Second World War. The concept itself was put forward in 1961 by physicist Alvin Weinberg, and further developed by historian of science Derek De Solla Price in his pioneering book, Little Science, Big Science. “The large-scale character of modern science, new and shining and all powerful, is so apparent that the happy term ‘Big Science'' has been coined to describe it” (De Solla Price, 1963). Weinberg noted that science had become ‘big'' in two ways. First, through the development of elaborate research instrumentation, the use of which requires large research teams, and second, through the explosive growth of scientific research in general. More recently, big science has come to refer to a diverse but strongly related set of changes in the organization of scientific research. This includes expensive equipment and large research teams, but also the increasing industrialization of research activities, the escalating frequency of interdisciplinary and international collaborations, and the increasing manpower needed to achieve research goals (Galison & Hevly, 1992). Many areas of biological research have shifted in these directions in recent years and have radically altered the methods by which biologists generate scientific knowledge.Despite this long history of collaboration, laboratory biology remained ‘small-scale'' until the rising prominence of molecular biology changed the research landscapeUnderstanding the implications of this change begins with an appreciation of the history of collaborations in the life sciences—biology has long been a collaborative effort. Natural scientists accompanied the great explorers in the grand alliance between science and exploration during the sixteenth and seventeenth centuries (Capshew & Rader, 1992), which not only served to map uncharted territories, but also contributed enormously to knowledge of the fauna and flora discovered. These early expeditions gradually evolved into coordinated, multidisciplinary research programmes, which began with the International Polar Years, intended to concentrate international research efforts at the North and South Poles (1882–1883; 1932–1933). The Polar Years became exemplars of large-scale life science collaboration, begetting the International Geophysical Year (1957–1958) and the International Biological Programme (1968–1974).For Weinberg, the potentially negative consequences associated with big science were “adminstratitis, moneyitis, and journalitis”…Despite this long history of collaboration, laboratory biology remained ‘small-scale'' until the rising prominence of molecular biology changed the research landscape. During the late 1950s and early 1960s, many research organizations encouraged international collaboration in the life sciences, spurring the creation of, among other things, the European Molecular Biology Organization (1964) and the European Molecular Biology Laboratory (1974). In addition, international mapping and sequencing projects were developed around model organisms such as Drosophila and Caenorhabditis elegans, and scientists formed research networks, exchanged research materials and information, and divided labour across laboratories. These new ways of working set the stage for the HGP, which is widely acknowledged as the cornerstone of the current ‘post-genomics era''. As an editorial on ‘post-genomics cultures'' put it in the journal Nature, “Like it or not, big biology is here to stay” (Anon, 2001).Just as big science is not new, neither are concerns about its consequences. As early as 1948, the sociologist Max Weber worried that as equipment was becoming more expensive, scientists were losing autonomy and becoming more dependent on external funding (Weber, 1948). Similarly, although Weinberg and De Solla Price expressed wonder at the scope of the changes they were witnessing, they too offered critical evaluations. For Weinberg, the potentially negative consequences associated with big science were “adminstratitis, moneyitis, and journalitis”; meaning the dominance of science administrators over practitioners, the tendency to view funding increases as a panacea for solving scientific problems, and progressively blurry lines between scientific and popular writing in order to woo public support for big research projects (Weinberg, 1961). De Solla Price worried that the bureaucracy associated with big science would fail to entice the intellectual mavericks on which science depends (De Solla Price, 1963). These concerns remain valid and have been voiced time and again.As big science represents a major investment of time, money and manpower, it tends to determine and channel research in particular directions that afford certain possibilities and preclude others (Cook & Brown, 1999). In the worst case, this can result in entire scientific communities following false leads, as was the case in the 1940s and 1950s for Soviet agronomy. Huge investments were made to demonstrate the superiority of Lamarckian over Mendelian theories of heritability, which held back Russian biology for decades (Soyfer, 1994). Such worst-case scenarios are, however, rare. A more likely consequence is that big science can diminish the diversity of research approaches. For instance, plasma fusion scientists are now under pressure to design projects that are relevant to the large-scale International Thermonuclear Experimental Reactor, despite the potential benefits of a wide array of smaller-scale machines and approaches (Hackett et al, 2004). Big science projects can also involve coordination challenges, take substantial time to realize success, and be difficult to evaluate (Neal et al, 2008).Importantly, big science projects allow for the coordination and activation of diverse forms of expertise across disciplinary, national and professional boundariesAnother danger of big science is that researchers will lose the intrinsic satisfaction that arises from having personal control over their work. Dissatisfaction could lower research productivity (Babu & Singh, 1998) and might create the concomitant danger of losing talented young researchers to other, more engaging callings. Moreover, the alienation of scientists from their work as a result of big science enterprises can lead to a loss of personal responsibility for research. In turn, this can increase the likelihood of misconduct, as effective social control is eroded and “the satisfactions of science are overshadowed by organizational demands, economic calculations, and career strategies” (Hackett, 1994).Practicing scientists are aware of these risks. Yet, they remain engaged in large-scale projects because they must, but also because of the real benefits these projects offer. Importantly, big science projects allow for the coordination and activation of diverse forms of expertise across disciplinary, national and professional boundaries to solve otherwise intractable basic and applied problems. Although calling for international and interdisciplinary collaboration is popular, practicing it is notably less popular and much harder (Weingart, 2000). Big science projects can act as a focal point that allows researchers from diverse backgrounds to cooperate, and simultaneously advances different scientific specialties while forging interstitial connections among them. Another major benefit of big science is that it facilitates the development of common research standards and metrics, allowing for the rapid development of nascent research frontiers (Fujimura, 1996). Furthermore, the high profile of big science efforts such as the HGP and CERN draw public attention to science, potentially enhancing scientific literacy and the public''s willingness to support research.Rather than arguing for or against big science, molecular biology would best benefit from strategic investments in a diverse portfolio of big, little and ‘mezzo'' research projectsBig science can also ease some of the problems associated with scientific management. In terms of training, graduate students and junior researchers involved in big science projects can gain additional skills in problem-solving, communication and team working (Court & Morris, 1994). The bureaucratic structure and well-defined roles of big science projects also make leadership transitions and researcher attrition easier to manage compared with the informal, refractory organization of most small research projects. Big science projects also provide a visible platform for resource acquisition and the recruitment of new scientific talent. Moreover, through their sheer size, diversity and complexity, they can also increase the frequency of serendipitous social interactions and scientific discoveries (Hackett et al, 2008). Finally, large-scale research projects can influence scientific and public policy. Big science creates organizational structures in which many scientists share responsibility for, and expectations of, a scientific problem (Van Lente, 1993). This shared ownership and these shared futures help coordinate communication and enable researchers to present a united front when advancing the potential benefits of their projects to funding bodies.Given these benefits and pitfalls of big science, how might molecular biology best proceed? Petsko''s response is that, “[s]cientific priorities must, for the most part, be set by the free exchange of ideas in the scientific literature, at meetings and in review panels. They must be set from the bottom up, from the community of scientists, not by the people who control the purse strings.” It is certainly the case, as Petsko also acknowledges, that science has benefited from a combination of generous public support and professional autonomy. However, we are less sanguine about his belief that the scientific community alone has the capacity to ascertain the practical value of particular lines of inquiry, determine the most appropriate scale of research, and bring them to fruition. In fact, current mismatches between the production of scientific knowledge and the information needs of public policy-makers strongly suggest that the opposite is true (Sarewitz & Pielke, 2007).Instead, we maintain that these types of decision should be determined through collective decision-making that involves researchers, governmental funding agencies, science policy experts and the public. In fact, the highly successful HGP involved such collaborations (Lambright, 2002). Taking into account the opinions and attitudes of these stakeholders better links knowledge production to the public good (Cash et al, 2003)—a major justification for supporting big biology. We do agree with Petsko, however, that large-scale projects can develop pathological characteristics, and that all programmes should therefore undergo regular assessments to determine their continuing worth.Rather than arguing for or against big science, molecular biology would best benefit from strategic investments in a diverse portfolio of big, little and ‘mezzo'' research projects. Their size, duration and organizational structure should be determined by the research question, subject matter and intended goals (Westfall, 2003). Parties involved in making these decisions should, in turn, aim at striking a profitable balance between differently sized research projects to garner the benefits of each and allow practitioners the autonomy to choose among them.This will require new, innovative methods for supporting and coordinating research. An important first step is ensuring that funding is made available for all kinds of research at a range of scales. For this to happen, the current funding model needs to be modified. The practice of allocating separate funds for individual investigator-driven and collective research projects is a positive step in the right direction, but it does not discriminate between projects of different sizes at a sufficiently fine resolution. Instead, multiple funding pools should be made available for projects of different sizes and scales, allowing for greater accuracy in project planning, funding and evaluation.It is up to scientists and policymakers to discern how to benefit from the advantages that ‘bigness'' has to offer, while avoiding the pitfalls inherent in doing soSecond, science policy should consciously facilitate the ‘scaling up'', ‘scaling down'' and concatenation of research projects when needed. For instance, special funds might be established for supporting small-scale but potentially transformative research with the capacity to be scaled up in the future. Alternatively, small-scale satellite research projects that are more nimble, exploratory and risky, could complement big science initiatives or be generated by them. This is also in line with Petsko''s statement that “the best kind of big science is the kind that supports and generates lots of good little science.” Another potentially fruitful strategy we suggest would be to fund independent, small-scale research projects to work on co-relevant research with the later objective of consolidating them into a single project in a kind of building-block assembly. By using these and other mechanisms for organizing research at different scales, it could help to ameliorate some of the problems associated with big science, while also accruing its most important benefits.Within the life sciences, the field of ecology perhaps best exemplifies this strategy. Although it encompasses many small-scale laboratory and field studies, ecologists now collaborate in a variety of novel organizations that blend elements of big, little and mezzo science and that are designed to catalyse different forms of research. For example, the US National Center for Ecological Analysis and Synthesis brings together researchers and data from many smaller projects to synthesize their findings. The Long Term Ecological Research Network consists of dozens of mezzo-scale collaborations focused on specific sites, but also leverages big science through cross-site collaborations. While investments are made in classical big science projects, such as the National Ecological Observatory Network, no one project or approach has dominated—nor should it. In these ways, ecologists have been able to reap the benefits of big science whilst maintaining diverse research approaches and individual autonomy and still being able to enjoy the intrinsic satisfaction associated with scientific work.Big biology is here to stay and is neither a curse nor a blessing. It is up to scientists and policy-makers to discern how to benefit from the advantages that ‘bigness'' has to offer, while avoiding the pitfalls inherent in so doing. The challenge confronting molecular biology in the coming years is to decide which kind of research projects are best suited to getting the job done. Molecular biology itself arose, in part, from the migration of physicists to biology; as physics research projects and collaborations grew and became more dependent on expensive equipment, appreciating the saliency of one''s own work became increasingly difficult, which led some to seek refuge in the comparatively little science of biology (Dev, 1990). The current situation, which Petsko criticizes in his Opinion article, is thus the result of an organizational and intellectual cycle that began more than six decades ago. It would certainly behoove molecular biologists to heed his warnings and consider the best paths forward.? Open in a separate windowNiki VermeulenOpen in a separate windowJohn N. ParkerOpen in a separate windowBart Penders     

Sexual adaptations to high density in hermaphrodites

Summary

Hermaphrodites are generally seen as species adapted to conditions of low mate availability. This is primarily because hermaphrodites can adjust allocation of resources to each sex function in response to current conditions, making reproduction more efficient. Adaptation to low density is further enhanced because many have the ability to self-fertilize and because the encounter rate of potential mates is twice as high for a hermaphroditic than for a gonochoric species. Yet, many hermaphrodites often occur at consistently high densities. Herein I review the consequences of high density on hermaphrodite sexual behaviour and show that this approach can explain the presence of a number of obvious adaptations known from hermaphrodites. These adaptations cannot be explained by assuming that low density has been the rule in their evolutionary past.