The increasing divide between First and Third Worlds: science, collaboration and conservation of Third World aquatic ecosystems

1. Ten of the leading journals in the field of freshwater ecology were identified using the Science Citation Index’s Journal Citation Reports. These journals were surveyed to assess the levels and patterns of collaboration in research initiatives in regions of the Third World. Membership demographics of five professional societies in this field were also examined to elucidate distribution patterns of practitioners in the field. 2. In total, 8960 papers were surveyed, of which only forty were published in a language other than English. Senior authors came from 114 of the 130 different countries listed among authors’ addresses. Of these, forty-five were from Third World countries and sixty-nine from the First World. Five countries were responsible for 60.64% of the papers submitted; the United States = 25.65%; Canada = 11.55%; Australia = 10.15%; the United Kingdom = 6.73%; New Zealand = 6.56%. Multi-authored papers accounted for 73.05% of all papers. 3. Papers by authors from Third World countries accounted for only 10.93% of single-author papers and less than 10% of multi-authored papers. Collaboration was found in 73.05% of the papers surveyed, the vast majority of which (87.39%) was between authors from First World countries. Only 825 (9.21%) of the papers surveyed involved authors from different countries. Most of this collaboration (72.36%) was between authors from different First World countries. 4. Some 1038 papers surveyed included research undertaken in, or included authors from, Third World countries. The majority of these papers (69.08%) were submitted by authors from Third World countries, involving either multiple or single authorship. The third most common publication relating to research in Third World regions (17.4%) came from single-author papers in which the authors were from a First World country. Only four of the papers surveyed were submitted by single authors from Third World countries working in First World countries. 5. There is a disproportionate representation of taxonomic (20.3%) and marine (10.5%) papers from the Third World regions in comparison to both lentic (8.0%) and lotic (7.4%) papers. 6. Membership demographics of the professional societies surveyed continue to reflect the historical origins of freshwater ecology. More than 80% of members in the three largest societies examined are registered in Europe and North America, while membership of the remaining societies remains largely regional. 7. It is argued that present levels of collaboration and technology transfer from the First World to the Third World are inadequate and that, given the widening gulf in terms of personnel and resources, the future of essential research on inland waters in the Third World does not bode well unless in situ capacity building within Third World countries becomes a target of First World research and funding agencies.     

Articles by Latin American Authors in Prestigious Journals Have Fewer Citations

Background

The journal Impact factor (IF) is generally accepted to be a good measurement of the relevance/quality of articles that a journal publishes. In spite of an, apparently, homogenous peer-review process for a given journal, we hypothesize that the country affiliation of authors from developing Latin American (LA) countries affects the IF of a journal detrimentally.

Methodology/Principal Findings

Seven prestigious international journals, one multidisciplinary journal and six serving specific branches of science, were examined in terms of their IF in the Web of Science. Two subsets of each journal were then selected to evaluate the influence of author''s affiliation on the IF. They comprised contributions (i) with authorship from four Latin American (LA) countries (Argentina, Brazil, Chile and Mexico) and (ii) with authorship from five developed countries (England, France, Germany, Japan and USA). Both subsets were further subdivided into two groups: articles with authorship from one country only and collaborative articles with authorship from other countries. Articles from the five developed countries had IF close to the overall IF of the journals and the influence of collaboration on this value was minor. In the case of LA articles the effect of collaboration (virtually all with developed countries) was significant. The IFs for non-collaborative articles averaged 66% of the overall IF of the journals whereas the articles in collaboration raised the IFs to values close to the overall IF.

Conclusion/Significance

The study shows a significantly lower IF in the group of the subsets of non-collaborative LA articles and thus that country affiliation of authors from non-developed LA countries does affect the IF of a journal detrimentally. There are no data to indicate whether the lower IFs of LA articles were due to their inherent inferior quality/relevance or psycho-social trend towards under-citation of articles from these countries. However, further study is required since there are foreseeable consequences of this trend as it may stimulate strategies by editors to turn down articles that tend to be under-cited.     

Bibliometric analysis of global scientific research on carbapenem resistance (1986–2015)

Background

Antimicrobial resistance is a global public health challenge and carbapenem resistance, in particular, is considered an urgent global health threat. This study was carried out to give a bibliometric overview of literature on carbapenem resistance. In specific, number of publications, top productive countries and institutes, highly cited articles, citation analysis, co-authorships, international collaboration, top active authors, and journals publishing articles on carbapenem resistance were analyzed and discussed.

Methods

Specific keywords pertaining to carbapenem resistance were used in Scopus database. Quantitative and qualitative analysis of retrieved data were presented using appropriate bibliometric indicators and visualization maps.

Results

A total of 2617 journal articles were retrieved. The average number of citations per article was of 21.47. The growth of publications showed a dramatic increase from 2008 to 2015. Approximately 9 % of retrieved articles on carbapenem resistance were published in Antimicrobial Agents and Chemotherapy journal. Retrieved articles were published by 102 different countries. The United States of America (USA) contributed most with 437 (16.70 %) articles followed by China with 257 (9.82 %) articles. When productivity was stratified by population size, Greece ranked first followed by France. Greece also ranked first when data were stratified by gross domestic product (GDP). Asian countries have lesser international collaboration compared with other countries in the top ten list. Five of top ten productive institutes were Europeans (France, the UK, Greece, Italy, and Switzerland) and two were Asians (China and South Korea). Other active institutes included an Israeli and a Brazilian institute. Four of the top ten cited articles were published in Antimicrobial Agents and Chemotherapy journal and two were published in The Lancet Infectious Diseases.

Conclusion

There was a dramatic increase in number of publications on carbapenem resistance in the past few years. These publications were produced from different world regions including Asia, Europe, Middle East, and Latin America. International collaboration needs to be encouraged particularly for researchers in Asia. Molecular biology and epidemiology dominated the theme of the top ten cited articles on carbapenem resistance. This bibliometric study will hopefully help health policy makers in planning future research and allocating funds pertaining to carbapenem resistance.

     

全球北极底栖生物研究文献计量分析

以Thomson Reuters的Web of Science信息平台提供的SCI-E数据库为数据源,检索到从1991年至2012年期间全球北极底栖生物研究论文2127篇,利用Note Express软件,分析22年间论文发表的年度、国家、机构、作者、期刊和学科等方面的分布特征,结果表明:1)全球北极底栖生物研究论文数量、篇均作者数和篇均参考文献数都在逐年增加;2)研究论文涉及58个国家或地区,位于前7位的国家依次是美国、德国、加拿大、挪威、俄罗斯、英国和丹麦;美国、加拿大、挪威和丹麦是该领域国际合作研究最主要的国家;3)论文涉及1364个机构,前20名的研究机构中,美国有6家,德国、加拿大和挪威各有3家,俄罗斯和丹麦各有2家,波兰有1家。俄罗斯、丹麦、波兰、德国和挪威超过60%的研究力量集中在位列前20位的相关机构中。俄罗斯科学院论文总量排列首位,德国阿尔弗雷德魏格纳极地与海洋研究中心和基尔大学论文的h指数最高为32;4)论文涉及最多的4个学科是海洋与淡水生物学、生态学、海洋学和多学科地球科学。Polar Biology和Marine Ecology Progress Series是发表该领域最核心的期刊。还对中国在该领域的研究现状进行了简要的分析。从文献计量学角度揭示了全球北极底栖生物研究现状,为提升我国该领域研究的国际竞争力提供科学参考。     

Who is publishing in Theriogenology and on what subjects?

An analysis of 503 articles published in the journal Theriogenology in 1984, 1987 and 1990 was conducted to identify research trends and researchers publishing in the journal. A 30.5% increase in the number of papers published was found for 1990. During the 3yr period studied, the United States and Canada accounted for 63.1% of the total number of articles published, followed by European countries with 14.3%, and by Asia with 12.0%. At least 1 paper was published from 41 countries. The United States, at the top of the list, increased its share from 16% in 1984 to 21% in 1990. The number of papers from Japan increased significantly while the percentage of participation from Europe declined. The female animal was the sole subject of 63.2% of the articles, and cattle were the most researched species, appearing in 44.3% of the studies. Although the estrous cycle was the most studied reproductive event in all 3 yr, there was also a trend for the popularity of this topic to decrease in favor of the subject fertilization. The number of authors per paper increased significantly over the years analyzed, as did the number of studies carried out in international cooperation. Institutes of higher education were represented in almost 70% of the papers, followed by research institutes (12.8%). The present analysis confirms the central role that the journal Theriogenology plays in the world-wide communication of research results in animal reproduction.     

The scientific publications of AIFM members in 2015–2019: A survey of the FutuRuS working group

PurposeWithin the Italian Association of Medical Physics and Health Physics (AIFM) working group “FutuRuS” we carried out a survey regarding the number of the peer-reviewed articles by AIFM members.MethodsWe surveyed papers published in the years 2015–2019. Data extracted from Scopus included information regarding authors, title, journal, impact factor (IF), leading or standard authorship by AIFM members, keywords, type of collaboration (monocentric/multicentric/international), area of interest [radiation oncology (RO), radiology (RAD), nuclear medicine (NM), radioprotection (RP) and professional issue (PI)] and topics.ResultsWe found 1210 papers published in peer-reviewed journals: 48%, 22%, 16%, 6%, 2 and 6% in RO, RAD, NM, RP, PI and other topics, respectively. Forty-seven percent of the papers involved monocentric teams, 31% multicentric and 22% international collaborations. Leading authorship of AIFM members was in 56% of papers, with a corresponding IF equal to 52% of the total IF (3342, IF_mean = 2.8, IF_max = 35.4). The most represented journal was Physica Medica, with 15% of papers, while a relevant fraction of IF (54%) appeared in clinically oriented journals. The number of papers increased significantly between 2015 and 2016 and remained almost constant in 2017–2019.ConclusionsThis survey led to the first quantitative assessment of the number and theme distribution of peer-reviewed scientific articles contributed by AIFM members. It constitutes a ground basis to support future AIFM strategies and promote working groups on scientific activity of medical physicists, and to build the basis for rational comparison with other countries, first of all within Europe.     

Preprinting is positively associated with early career researcher status in ecology and evolution

The usage of preprint servers in ecology and evolution is increasing, allowing research to be rapidly disseminated and available through open access at no cost. Early Career Researchers (ECRs) often have limited experience with the peer review process, which can be challenging when trying to build publication records and demonstrate research ability for funding opportunities, scholarships, grants, or faculty positions. ECRs face different challenges relative to researchers with permanent positions and established research programs. These challenges might also vary according to institution size and country, which are factors associated with the availability of funding for open access journals. We predicted that the career stage and institution size impact the relative usage of preprint servers among researchers in ecology and evolution. Using data collected from 500 articles (100 from each of two open access journals, two closed access journals, and a preprint server), we showed that ECRs generated more preprints relative to non‐ECRs, for both first and last authors. We speculate that this pattern is reflective of the advantages of quick and open access research that is disproportionately beneficial to ECRs. There is also a marginal association between first author, institution size, and preprint usage, whereby the number of preprints tends to increase with institution size for ECRs. The United States and United Kingdom contributed the greatest number of preprints by ECRs, whereas non‐Western countries contributed relatively fewer preprints. This empirical evidence that preprint usage varies with the career stage, institution size, and country helps to identify barriers surrounding large‐scale adoption of preprinting in ecology and evolution.     

基于文献计量的植物雌雄异株研究进展

雌雄异株植物是研究植物性别的理想材料,同时作为生态系统的重要组成部分,对生物多样性的维持与保护起着重要作用。该文从文献计量学角度综述了雌雄异株植物相关研究的进展。通过检索Web of Science(WOS)平台的SCI-E数据库和CNKI数据库的有关雌雄异株研究的文献数据,从文献年代分布、期刊分布、研究国家与机构、核心作者和高引论文等方面进行了分析,并借助CitespaceⅢ信息可视化软件绘制雌雄异株植物研究的科学知识图谱,总结了雌雄异株研究的热点和前沿。结果表明:WOS数据库中,雌雄异株植物研究呈现快速上升趋势,就发文总量来看,发文前五的国家为美国、日本、加拿大、英格兰和中国。其中,美国发文量占比为31.03%;中国科学院为发文量最多的机构,发文占比3.36%,其次为牛津大学(2.613%),多伦多大学位列第三(2.427%);中国,巴西和印度三国,西班牙马萨里克大学和北京林业大学两个研究机构近5年来在该领域发文增量较快。论文主要集中在植物科学、环境科学与生态学和遗传学等学科。载文量前十位的期刊累计载文占比高达24.13%,发文量最多的期刊为American Journal of Botany,占总发文量的6.07%,其次为Evolution(2.80%),Annals of Botany(2.52%)排名第三。发文最多的作者为捷克科学院的VYSKOT B,发文占总数的2.57%,高引论文大多出自美国学者之手。从CNKI数据库看,西华师范大学、北京林业大学和河南师范大学发文数量位列前三,发文量最高的期刊为《生命世界》,占总发文量的3.00%。综合Web of Science和CNKI两大数据库的文献来看,青杨和番木瓜作为研究雌雄异株植物的模式植物,近年发文较多。当前的研究热点主要集中在雌雄性别决定,繁殖代价,雌雄个体对环境因子的响应差异等方面。     

A tale of four stories: soil ecology, theory, evolution and the publication system

Background

Soil ecology has produced a huge corpus of results on relations between soil organisms, ecosystem processes controlled by these organisms and links between belowground and aboveground processes. However, some soil scientists think that soil ecology is short of modelling and evolutionary approaches and has developed too independently from general ecology. We have tested quantitatively these hypotheses through a bibliographic study (about 23000 articles) comparing soil ecology journals, generalist ecology journals, evolutionary ecology journals and theoretical ecology journals.

Findings

We have shown that soil ecology is not well represented in generalist ecology journals and that soil ecologists poorly use modelling and evolutionary approaches. Moreover, the articles published by a typical soil ecology journal (Soil Biology and Biochemistry) are cited by and cite low percentages of articles published in generalist ecology journals, evolutionary ecology journals and theoretical ecology journals.

Conclusion

This confirms our hypotheses and suggests that soil ecology would benefit from an effort towards modelling and evolutionary approaches. This effort should promote the building of a general conceptual framework for soil ecology and bridges between soil ecology and general ecology. We give some historical reasons for the parsimonious use of modelling and evolutionary approaches by soil ecologists. We finally suggest that a publication system that classifies journals according to their Impact Factors and their level of generality is probably inadequate to integrate “particularity” (empirical observations) and “generality” (general theories), which is the goal of all natural sciences. Such a system might also be particularly detrimental to the development of a science such as ecology that is intrinsically multidisciplinary.     

The influence of “Homage to Santa Rosalia” on aquatic ecology: a scientometric approach

In 1959, G.E. Hutchinson provided a general explanation for the diversity of species in his paper “Homage to Santa Rosalia or why are there so many kinds of animals?” To assess the contribution of the ideas Hutchinson introduced in “The Homage” to aquatic ecology research, we performed a bibliometric evaluation of all the articles that cited this paper between 1960 and 2009. The articles were retrieved using the database from Thomson Reuters (ISI Web of Knowledge) in March 2009. For each paper, we first identified the studied environment (terrestrial, marine or freshwater) and whether the study was theoretical or empirical. For marine and freshwater studies, we recorded the journal where the article was published, the year of publication, the number of citations, the taxonomic group (e.g. fish, phytoplankton, zooplankton, macroinvertebrates or macrophytes), the habitat (e.g. wetlands, lakes, rivers, streams or ocean) and the main ideas addressed. A total of 1345 articles cited “The Homage”, and the number of citations increased significantly with time. Most of the articles that cited “The Homage” described research carried out in a terrestrial environment or were theoretical, and a lesser number of citations came from freshwater and marine papers, which used mainly fish and invertebrates as model organisms. In the aquatic sciences, most of the papers discussed the influences of competition and energy (productivity) on diversity. Our results indicate that “The Homage” can still be considered a “citation classic” and a breakthrough contribution, and that it is still having a great impact on different fields of ecology, including limnology and marine ecology.     

A quantitative ranking of Canada's research output of original human studies for the decade 1989 to 1998

BACKGROUND: Since 1987 research articles have been catalogued with the author''s affiliation address in the 40 databases of the Medical Literature Analysis and Retrieval System (MEDLARS) of the National Library of Medicine, Bethesda, Md. The present study was conducted to examine the Canadian entries in MEDLARS to interpret past and future trends and to combine the MEDLARS demographic data with data from other sources to rank Canadian research output of human studies both nationally and internationally. METHODS: The PubMed Web site of the National Library of Medicine was used to count medical articles archived in MEDLARS and published from Jan. 1, 1989, through Dec. 31, 1998. The articles attributed to Canadian authors were compared by country, province, city, medical school, hospital, article type, journal and medical specialty. RESULTS: During the study period Canadian authors contributed on average 3% (standard deviation [SD] 0.2%) of the worldwide MEDLARS content each year, which translated to a mean of 11,067 (SD 1037) articles per year; 49% were human studies, of which 13% were clinical or controlled trials, and 55% involved people aged 18 years or less. In total, 68% of the articles were by authors affiliated with Canadian medical schools; those affiliated with the University of Toronto accounted for the greatest number (8604), whereas authors affiliated with McGill University had the greatest rate of annual increase in the quantity published (8%). Over one-third (38%) of the articles appeared in Canadian journals. When counted by specialty, 17% of the articles were by authors with clinical specialties, 5% by those with surgical specialties and 3% by those with laboratory specialties. INTERPRETATION: The annual rate of increase in research output for Canada was more than 3 times higher than that seen world wide. Canada is now ranked seventh among countries contributing human studies to MEDLARS. The increase indicates that Canada''s medical schools are productive, competitive in making contributions to medical science and are supporting Canadian journals.     

More topics from the tropics: additional thoughts to Mammides et al.

Most studies on tropical conservation questions are conducted by researchers of developed countries from the north. This geographic disconnection was recently criticised by Mammides et al. Here, we reflect on their findings and add further views from scientist’s and journal editor’s perspectives. We argue that journals are, a priori, most strongly interested in research questions and approaches that will likely increase their scientific impact and prestige. This is rarely compatible with publishing articles on questions with restricted global impact or based on single taxa. We question whether small changes in the editorial policy of international conservation journals will considerably improve the geographic diversity in key conservation publications. Rather, thematic scopes of the leading conservation journals should be modified, preferably in close collaboration with leading conservationists from the south. We are convinced that long-term investments in the tropics will create a stronger local scientific community, thus bolstering academic morale, and finally may lead to an increase in the submission and acceptance rate of articles written from scientists from these regions.     

Plant science research productivity in Chile during the past 20 years

The purpose of this study was to carry out a bibliometric analysis of the articles published in Chile during 1987-2006 that were categorized into the Plant Science discipline by ISI. The data was extracted from the Web of Science datábase, obtaining a total of 911 articles for analysis. Almost half of the articles were the outcome of an international collaboration, the United States being the country with more collaborative links with Chile within this discipline. A list was made with the 10 most-cited articles and 10 most frequently used journals. The analysis showed that almost 50% of the articles were concentrated in 10 different journals. The number of articles produced each year revealed a steady growth in scientific production since 1987. This is probably related to the progressive interaction between industry and public-research institutions.     

HIV/AIDS research conducted in the developing world and sponsored by the developed world: reporting of research ethics committee review in two countries

We explored how often journal articles reporting HIV research sponsored by a developed country, but conducted in a developing country, mention research ethics committee (REC) approval from both countries, and what factors are involved. Of all such 2007 articles on Medline conducted in one of four developing countries (N = 154), only 52% mentioned such dual approval. Mention of dual vs. single approval was more likely among articles with ≥ 50% sponsor country authors, and the United States as the sponsor country. Also, dual approval was more likely among articles that mentioned informed consent and funding, had ≥ 50% sponsor country authors, were biomedical (vs. psychosocial), and appeared in journals adopting International Committee Medical Journal Editors (ICMJE) guidelines. Dual approval was thus obtained in only half of the articles and was associated with ethical and logistic issues, indicating the need for clearer and more universally accepted guidelines.     

Invasive species in Southeast Asia: the knowledge so far

This review deals with alien species invasion in Southeast Asia, an important conservation and management concern in the region. I report on the current and potential future impacts of biological invasions on biodiversity in Southeast Asia. Current knowledge of the invasive species in Southeast Asia is mostly based on anecdotal observations. Nevertheless, I attempt to compile existing empirical evidence on the negative effects of the biological invaders found in the region. These impacts include displacement of native biota, modification of ecosystems, hybridization, environmental disturbance, and economic loss. Any effective counter-measure will need to involve a multi-national strategy, yet such measure is challenging due to a broad spectrum of political and economic development models among the Southeast Asian countries. An overview of the taxonomic structure of the invasive species in Southeast Asia shows that the invasive plant and fish are the most represented taxonomic groups in all countries. The current research effort in invasion ecology from Southeast Asia is not being up to international standard in comparison to other regions, and the absence of recent international journal articles on invasive plant species reveals the biases in biological invasion-related research. The lack of research capacity and financial support from governments, and the inability to disseminate scholarly data in international journals are the possible reasons for the dearth of research literature on biological invasions from the region. Finally, a forward-looking agenda for the region should include improving the quality and quantity of biological invasion research; adopting a tough approach to the illegal release of wildlife; and applying multi-national strategies that integrate data sharing, prioritization, public awareness, policy work, capacity building, conservation actions and surveillance.     

近十年的国际植被物候研究文献发展态势分析

基于Web of Science数据库的检索结果,利用Histcite、Bibexcel和Netdraw对国际植被物候研究文献进行计量分析。结果表明:1 060篇相关文献刊载于288种期刊,平均载文3.68篇; 共分33个研究方向; 3 380位作者(第一作者904位)、69个国家或地区、1 172个组织参与; 国际合作发文310篇,占比29.25%; 其中中美合作居第一(19次)。分析还表明:2002～2007年是该领域重要发展期; 国际植被物候研究热点主要集中在基于气候(climate)-物候的田间局地观测和基于遥感(remote sensing)的大尺度物候研究。     

Negative changes in the scientific publication process in ecology: potential causes and consequences

1. Increasingly viewed to have societal impact and value, science is affected by complex changes such as globalisation and the increasing dominance of commercial interest. As a result, technical advancements, financial concerns, institutional prestige and journal proliferation have created challenges for ecological and other scientific journals and affected the perception of both researchers and the public about the science that they publish. 2. Journals are now used for more than dissemination of scientific research. Institutions use journal rankings for a variety of purposes and often require a pre‐established number of articles in hiring and budgetary decisions. Consequently, journal impact factors have achieved greater importance, and the splitting of articles into smaller parcels of information (‘salami‐slicing’) to increase numbers of publications has become more frequent. 3. Journals may prescribe upper limits to article length, even though the average length of articles for several ecological journals examined has increased over time. There are clear signs, however, that journals without length limits for articles will become rarer. In contrast to ecological journals, taxonomic journals are not following this trend. 4. Two case histories demonstrate how splitting longer ecological articles into a series of shorter ones results in both redundancy of information and actually increases the journal space used overall. Furthermore, with current rejection rates of ecological journals (often ～80%), many thin salami‐sliced articles jam the peer‐review system much longer (through resubmission after rejection) than unsliced articles previously did (e.g. when rejection rates were ～50%). In our experience, the increased pressure to publish many articles in ‘high‐impact’ journals also may decrease the attractiveness of a future scientific career in ecology to young people. 5. ‘Gatekeeping’ of journal quality has shifted from editors to reviewers, and several recent trends are apparent including: bias about appropriate statistical methods; reviewers being more rigid overall; non‐native English writers being criticised for poor communications skills; and favourable reviews being signed more often than unfavourable ones. In terms of production, outsourcing of copy editing has increased the final error rate of published material. 6. We supplemented our perceptions with those of older colleagues (～100 experienced ecologists) that responded to an informal survey on this topic (response rate: 81%). In the opinion of almost 90% of our respondents, the overall review process has changed and for 20% among them the professional quality of reviews has declined. 7. We, and many older colleagues, are convinced there have been some negative changes in the scientific publication process. If younger colleagues share this concern, we can collectively counter this deteriorating situation, because we are the key to the publishing and evaluation process.     

Mobility and International Collaboration: Case of the Mexican Scientific Diaspora

We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI). Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991–2001 and 2003–2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.     

Collaboration in scientific research: a critical need for freshwater ecology

1. Collaboration means actively working together to achieve things which could not be done alone. This article attempts to provide an overall, unified, guiding framework for collaboration in freshwater ecology by discussing aspects of collaboration at individual and organizational levels, and addressing international linkages.
2. The essential elements of collaboration are communication and trust, and effective project management. Barriers to effective collaboration include competition, organizational cultures and organizational instabilities.
3. The success of collaboration can be measured by tangible benefits such as increased numbers of peer-reviewed publications, the production of working models and a number of intangible benefits.
4. Interactions between individuals lie at the heart of an effective collaboration; organizational arrangements should facilitate this interaction. Some governments are encouraging collaboration to increase cost efficiency and allocate accountability. This trend should continue on an international level.
5. Collaboration is a key to future research in freshwater ecology.