United Nations system efforts to support the response to AIDS in China

In the last two years, we have seen a remarkable intensification in the response to AIDS in China. A number of organizations have joined and contributed to the efforts of the Chinese government in responding the AIDS epidemic in China. This article specifically describes the role of the United Nations in supporting and strengthening those responses. Achievements of the United Nations （UN） highlighted in the article include： strengthened leadership and political commitment to respond to AIDS; improved HIV/AIDS surveillance and information; expanded prevention efforts; improved treatment, care and support to people living with HIV and increased resources for AIDS programs. Additional roles of the United Nations system in the near future include strengthening national leadership by supporting the ‘three ones＇, i. e., one national plan on AIDS; one national coordinating authority for AIDS; and one monitoring and evaluation system for AIDS. In addition, the UN system is expected to strengthen alignment and harmonization of activities of all international organizations and improved accountability and oversight. Remaining challenges identified include increasing awareness of AIDS and reducing stigma and discrimination; reducing vulnerability and risk behaviour among specific groups; providing improved treatment, care and support for people living with HIV; promoting stronger engagement by civil society, and; addressing the gender dimensions of AIDS.     

United Nations system efforts to support the response to AIDS in China

In the last two years, we have seen a remarkable intensification in the response to AIDS in China. A number of organizations have joined and contributed to the efforts of the Chinese government in responding the AIDS epidemic in China. This article specifically describes the role of the United Nations in supporting and strengthening those responses.Achievements of the United Nations (UN) highlighted in the article include: strengthened leadership and political commitment to respond to AIDS; improved HIV/AIDS surveillance and information; expanded prevention efforts; improved treatment, care and support to people living with HIV and increased resources for AIDS programs. Additional roles of e., one national plan on AIDS; one national coordinating authority for AIDS; and one monitoring and evaluation system for AIDS. In addition, the UN system is expected to strengthen alignment and harmonization of activities of all international organizations and improved accountability and oversight. Remaining challenges identified include increasing awareness of AIDS and reducing stigma and discrimination; reducing vulnerability and risk behaviour among specific groups;providing improved treatment, care and support for people living with HIV; promoting stronger engagement by civil society, and; addressing the gender dimensions of AIDS.     

The incompatibility of the United Nations' goals and conventionalist ethical relativism

The Universal Draft Declaration on Bioethics and Human Rights seeks to provide moral direction to nations and their citizens on a series of bioethical concerns. In articulating principles, it ranks respect for human rights, human dignity and fundamental freedoms ahead of respect for cultural diversity and pluralism. This ranking is controversial because it entails the rejection of the popular theory, conventionalist ethical relativism. If consistently defended, this theory also undercuts other United Nations activities that assume member states and people around the world can reach trans-cultural judgments having moral authority about health, pollution, aggression, rights, slavery, and so on. To illustrate problems with conventionalist ethical relativism and the importance of rejecting it for reasons of health, human rights, human dignity and fundamental freedoms, the widespread practice of female genital circumcision or cutting is discussed. These surgeries are virtually a test case for conventionalist ethical relativism since they are widely supported within these cultures as religious and health practices and widely condemned outside them, including by the United Nations.     

Zooplankton research: the contribution of limnology to general ecological paradigms

Biotic interactions and density dependent processes are particularly important in the pelagic zone of a lake. Plankton has numerous properties (e.g., short life cycles, size structure) that makes them suitable objects for testing hypotheses and developing concepts relevant for general ecology. Zooplankton being in the center of aquatic food webs and influenced strongly by both bottom-up and top-down processes have often been used as models for ecological paradigms. The trophic-dynamic concept, the theory of population dynamics, and the analysis of predator-prey relationships are examples of successful contributions of zooplankton research. In recent years, zooplankton research has developed new ideas in community, population and evolutionary ecology. This is illustrated by studies on mechanisms of seasonal succession, competition and phenotypic plasticity. The new concept of physiological ecology is explained with copepod diapause behaviour. The blending of ideas from ecology and evolutionary genetics, which is undergoing a rapid development of new tools, will create new paradigms in the future, and zooplankton research will play an important part in this process.     

生态旅游区的景观生态问题及其调控

目前,在生态旅游开发过程中存在着许多生态破坏现象,严重影响生态旅游的可持续发展,是生态旅游区建设中亟待重视的问题。本文总结了当前我国生态旅游区在发展生态旅游过程中存在的生态破坏问题,并运用景观生态学、旅游生态学的原理和方法提出了解决生态旅游区生态问题的景观生态调控对策和措施,包括进行旅游景观生态规划、设计合理的旅游生态管理容量、对旅游景观结构进行生态化设计、构建景观生态安全格局、加强旅游生态教育和旅游环境监测等方面。     

全球生态问题与植物园的功能

本文概述了全球生态问题的热点和植物园可能起的作用。作者以许多具体的实例论证了资源植物和植物环境对人类生存的重要意义,阐明了植物园的功能,尤其在保护植物多样性,保护稀有濒危植物方面的重要作用。     

美国流域生态健康评价体系的发展和实践

为了达到《清洁水法》规定的水质目标,美国环境部门在过去20多年的实践中逐步发展形成了涵盖整个流域,包括水文、化学、生物等多重指标在内的全国性流域综合生态健康评价体系.该体系已经成为美国流域水质管理系统的重要组成部分,为水环境保护和水生生态系统恢复提供了有力支持.本文从法律行政框架、生态功能分析、生态健康指标、综合评价体系和流域监测系统等方面系统总结了美国环境管理部门,特别是联邦环境保护局在流域生态健康评价方面的发展和实践;并介绍了美国水生资源调查采用的河流、湖泊、河口、海湾、湿地流域健康评价系统.在此基础上,根据我国水环境保护和治理的实际情况,提出了建立流域生态健康科学评价和决策支持体系建议.     

Seeing the Forest for the Trees: Integrated Conservation and Development Projects and Local Perceptions of Conservation in Madagascar

This paper explores local perceptions of internationally financed conservation and development projects in Madagascar and the success of these projects at influencing perceptions. Interviews, surveys, and focus group sessions were conducted in the peripheral zones of three Malagasy national parks: Ranomafana, Andohahela, and Masoala. Relevant questions explored community demographics, socioeconomic status, and local perceptions of the parks. The principal finding is that while a majority of people living in the peripheral zones do find conservation a valuable goal, they see it as a luxury they cannot afford. Despite their efforts and innovation, conservation and development projects have had a minimal impact on socioeconomic or associational life in the Ranomafana and Andohahela peripheral zones, and a significant but modest impact in the Masoala peripheral zone, by providing economic alternatives to destructive resource use. As a result, they are limited in their success at promoting conservation outcomes.     

The incidence of Helicobacter pylori acquisition in children of a Canadian First Nations community and the potential for parent-to-child transmission

BACKGROUND AND AIMS: We have previously reported that Wasagamack, a Canadian First Nations community has a seroprevalence rate of Helicobacter pylori of 95% and a prevalence rate among children aged 0-12 years as measured by stool antigen testing of 56%. We aimed to determine the rate of infection acquisition and possible modes of transmission of childhood Helicobacter pylori infection in this Canadian First Nations community. METHODS: Children who were previously negative for H. pylori by stool antigen testing in August 1999 were eligible for enrollment in August 2000; 50 (77%) eligible children underwent stool collection. H. pylori stool antigen status was tested using the Premier Platinum HpSA test. Drinking water samples, maternal saliva, breast milk, local berries and flies were tested by three complementary H. pylori-specific PCR assays. Soothers or bottle nipples, collected from 16 children whose H. pylori stool antigen status was determined, were bathed in sterile water and this water was tested by PCR. RESULTS: Stool was positive for H. pylori in 16% (8/ 50) of children retested. Five had no other siblings infected and three had infected siblings. The mothers of all children infected were positive for H. pylori. The median age of newly infected children was 6 years (range 1-13 years). By PCR, 78% (18/23) mothers' saliva samples, 69% (11/16) soother water samples and 9% (1/11) water samples from infected homes tested positive. All of 24 sequenced PCR-produced DNA fragments from samples showed 99% homology with that from ATCC type strain H. pylori. CONCLUSIONS: The rate of childhood H. pylori acquisition was 16% over 1 year, and was not dependent on number of siblings infected. The finding of homologous H. pylori DNA in saliva and in soother water suggests the possibility of human to human transmission, particularly via an oral-oral route. Thus, there is the potential for further investigations in this population and other endemic communities that are directed at prevention of infection transmission via this modality.     

Diversity of ecological communities of the United States

Biodiversity, although recongnized as encompassing several levels of biological organization, is often thought of as species diversity. Three diversity estimates were calculated for the conterminous United States using satellite data acquired from the Advanced Very High Resolution Radiometer (AVHRR): land cover richness, vegetation richness, and vegetation clustering. Vegetation richness and vegetation clustering showed a scale-dependent relationship to elevation across the range of quadrat sizes from 500 to 50,000 mi². All diversity measures increased east to west, with a rather abrupt transition at the Colorado Front Range. The longitudinal diversity gradients found in this study are in contrast to the reported latitudinal and longitudinal gradients for species diversity.     

Cytopathology training in the United States – a personal view

In this review we present an outline of cytopathology training in the United States, for a non-US readership.     

A hierarchical ecological classification system along the NE Atlantic coast: focusing on the local scale (Cantabria,N Spain)

An ecological classification at the local scale may be a useful tool for conservation planning and for the implementation of specific management programmes in a region. For this purpose, a methodology previously applied on a small scale has been adapted to classify the coast of Cantabria (N Spain). This methodology includes a physical classification and biological validation. The shoreline was divided into 1 km stretches, and the abiotic variables (sea surface temperature, photosynthetically active radiation, significant wave height and coastal morphology) were recorded for each stretch. A hierarchical classification was proposed, with a first level that encompassed a grouping of quantitative variables based on SOM and k-mean analysis and a second level that subdivided the previous groups according to the categorical variable ‘coastal morphology’. To validate the classification using biological data, cover of intertidal macroalgal species was obtained at 14 sites along the study area, and several statistical analyses were applied to test the ecological significance of this classification. Three physical units were obtained (western (W), central (C) and eastern (E) coast), based on abiotic variables. Each group was then subdivided into subunits according to its coastal morphology (cliffs or wave-cut platforms). A general agreement between the macroalgal distribution and physical units was accomplished. In the lower intertidal, Bifurcaria bifurcata and Halopteris scoparia dominated the western and central areas, whereas Corallina spp./Ellisolandia elongata and Gelidium spp. were most abundant towards the east. In contrast, throughout the middle intertidal, Corallina. spp./E. elongata were the dominant taxa. The classification system developed in this study completes a hierarchical framework for classifying the NE Atlantic coast, a promising approach that permits the application of the most suitable resolution in each case study that could be applicable to a wide range of coastal areas.     

Pattern, process and prediction in aquatic ecology. A limnological view of some general ecological problems

1. New scientific concepts such as models of chaos, complex dynamics and non-linear interactions have the potential to contribute to an improved understanding of ecological patterns and processes. This paper discusses some of the known dynamics of phytoplankton, pelagic food chains and nutrient cycles in the light of some of these new concepts. The paper brings these new conceptual models together with data from a wide range of sources in an attempt to produce a synthesis of system behaviour which allows us to understand why some things are inherently more predictable than others. In particular it looks at the limnological management tools of empirical biomass models and biomanipulation and at the need for prediction of species composition. 2. The structures observed in ecosystems (nutrient pools, sizes, species, temporal/spatial patterns) show properties at a spectrum of scales, as do the processes (fluxes, grazing, competition). Both respond to a spectrum of external perturbations that may be climatologically or anthropogenically induced. Empirical biomass models work because of the annual averaging of pattern and process and because of some inherent properties of the functioning of pelagic ecosystems. Many aspects of ecosystem pattern and process vary in a regular way with trophic state. Examination of empirical data sets can lead to an improved understanding of system behaviour if questions are asked about why things happen the way they do. 3. Feedbacks between pattern, process and periodicity are seen to be an inherent property of the system. Understanding the fundamental dynamics of non-linear interactions in ecosystems may make it possible to exploit the external spectrum of environmental perturbations and to control system function. For example, by imposing external physical perturbations on pelagic systems it may be possible to manipulate the species composition of the phytoplankton community. Because of the complexity of possible interactions both ‘horizontally’ between species and ‘vertically’ within the food chain, any prediction of species composition will necessarily be probabilistic.     

The role of micro-organisms in the ecological connectivity of running waters

1. Riparian zones hold a central place in the hydrological cycle, owing to the prevalence of surface and groundwater interactions. In riparian transition zones, the quality of exfiltrating water is heavily influenced by microbial activities within the bed sediments. This paper reviews the role of micro-organisms in biogeochemical cycling in the riparian-hyporheic ecotone. 2. The production of organic substances, such as cellulose and lignin, by riparian vegetation is an important factor influencing the pathways of microbial processing in the riparian zone. For example, anaerobic sediment patches, created by entrainment of allochthonous organic matter, are focal sites of microbial denitrification. 3. The biophysical structure of the riparian zone largely influences in-stream microbial transformations through the retention of organic matter. Particulate and dissolved organic matter (POM and DOM) is retained effectively in the hyporheic zone, which drives biofilm development and associated microbial activity. 4. The structure of the riparian zone, the mechanisms of POM retention, the hydrological linkages to the stream and the intensity of key biogeochemical processes vary greatly along the river continuum and in relation to the geomorphic setting. However, the present state of knowledge of organic matter metabolism in the hyporheic zone suggests that lateral ecological connectivity is a basic attribute of lotic ecosystems. 5. Due to their efficiency in transforming POM into heterotrophic microbial biomass, attached biofilms form an abundant food resource for an array of predators and grazers in the interstitial environments of rivers and streams. The interstitial microbial loop, and the intensity of microbial production within the bed sediments, may be a primary driver of the celebrated high productivity and biodiversity of the riparian zone. 6. New molecular methods based on the analysis of the low molecular weight RNA (LMW RNA) allow unprecedented insights into the community structure of natural bacterial assemblages and also allow identification and study of specific strains hitherto largely unknown. 7. Research is needed on the development and evaluation of sampling methods for interstitial micro-organisms, on the characterization of biofilm structure, on the analysis of the biodegradable matter in the riparian-hyporheic ecotone, on the regulation mechanisms exerted on microbiota by interstitial predators and grazers, and on measures of microbial respiration and other key activities that influence biogeochemical cycles in running waters. 8. Past experiences from large-scale alterations of riparian zones by humans, such as the River Rhine in central Europe, undeniably demonstrate the detrimental consequences of disconnecting rivers from their riparian zones. A river management approach that uses the natural services of micro-organisms within intact riparian zones could substantially reduce the costs of clean, sustainable water supplies for humans.     

A seasonal and ecological study of the phytoplankton of Loch Lomond

The seasonal succession of phytoplankton in Loch Lomond has been studied both quantitatively and from observations on net plankton. From a qualitative investigation of net phytoplankton Loch Lomond may be described as diatom-desmid in nature although from the quantitative studies the general domination of the population by diatoms becomes clear. During the vernal phytoplankton increase diatoms contributed more than 90% of the population throughout the loch. The bulk of the phytoplankton production occurred in the southern region, where the standing crop was considerably greater throughout the year than in other regions of the loch.Patterns of seasonal succession are described for all species which make an important contribution to the productivity of the loch and the observed successions related to measured physical and chemical changes in the water. Explanations are put forward to account for the absence of a second (autumnal) pulse ofMelosira in Loch Lomond. The appearance ofAnabaena circinalis is a possible indication of the changing trophic status of the southern region of the loch.     

The systematic significance of flavonoids in Persea of the Southeastern United States

The systematic significance of flavonoid distribution in the southeastern United States taxa of Persea is discussed. The compounds thus far elucidated are glycosides based on quercetin, kaempferol, apigenin or luteolin.     

Nitrogen loss from deserts in the southwestern United States

A lower limit for nitrogen loss from desert ecosystems in the southwestern United States was estimated by comparing nitrogen inputs to the amount of nitrogen stored in desert soils and vegetation. Atmospheric input of nitrogen for the last 10 000 years was conservatively estimated to be 2.99 kg N/m². The amount of nitrogen stored in desert soils was calculated to be 0.604 kg N/m³ using extant data from 212 profiles located in Arizona, California, Nevada, and Utah. The average amount of nitrogen stored in desert vegetation is approximately 0.036 kg N/m².Desert conditions have existed in the southwestern United States throughout the last 10 000 years. Under such conditions, vertical leaching of nitrogen below a depth of 1 m is small (ca. 0.028 kg N/m² over 10 000 years) and streamflow losses of nitrogen from the desert landscape are negligible. Thus, the discrepancy found between nitrogen input and storage represents the amount of nitrogen lost to the atmosphere during the last 10 000 years. Loss of nitrogen to the atmosphere was calculated to be 2.32 kg N/m², which is 77% of the atmospheric inputs.Processes resulting in nitrogen loss to the atmosphere from desert ecosystems include wind erosion, ammonia volatilization, nitrification, and denitrification. Our analysis cannot assess the relative importance of these processes, but each is worthy of future research efforts.