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1.
What is a node?   总被引:2,自引:0,他引:2  
Biogeographic nodes can be characterized as sites of biological endemism, high diversity, distribution boundaries, anomalous absences, disjunct populations, taxonomic incongruence, parallelism and altitudinal anomalies. Their interpretation has depended on the evolutionary model used, in particular the mode of speciation: Croizat's vicariance or Mayr's ‘peripatric’ or ‘founder dispersal’ (=Darwin's ‘chance dispersal’, Hennig's ‘speciation by colonization’). All authors agree that the first process, together with movement of individual organisms and diaspores, occurs, but the second is much more controversial, with panbiogeographers and many geneticists denying its importance. Although nodes have often been interpreted as centres of origin – as in refugium theory – this is not accepted here as it fails to account for their constituting both centres and margins of distribution as well as zones of absence. Instead they are interpreted as sites of vicariance related to different kinds of tectonic activity which have been shown to occur in the same locality, such as terrane accretion, subduction, regional metamorphism, granitization, volcanism, faulting, folding, uplift, subsidence and regression of epicontinental seas. It is concluded that the identification of nodes is a more productive approach to biogeographic analysis than dividing a study area into ‘biogeographic regions’, which are usually based firmly on current geography and represent geological and biogeographic composites.  相似文献   

2.
Anatomical studies of the skin of mature White Fulani, N'Dama, Muturu and the Friesian cattle showed that there are significant regional and breeds differences in hair follicle density and depth. The hair follicle distribution per cm2 of skin was higher on the neck, ventral and the upper limb sites (2000 – 2496) than on the dorsal, midside and eye margins (1344 – 1920). Low densities were recorded on the horn margin, perineum and the lower limb sites (576 – 960). This regional distribution was consistent in all breeds except the White Fulani in which follicle densities were significantly lower for most body sites. Hair follicle depth was greater in the Friesians (1.63 ± 0.68 mm) than in the N'Dama (0.98 ± 0.13 mm), the White Fulani (0.91 ± 0.31 mm) and the Muturu (0.84 ± 0.25 mm) cattle. Among body sites, follicle depth was significantly greater on the horn margin, lower and upper limbs and the scrotum (1.16 – 1.48 mm) than on other body sites (0.86 – 0.98 mm). A significant negative correlation was found between hair follicle density and follicle depth.  相似文献   

3.
Oil palm cultivation is expanding rapidly into many of the world's most biodiverse tropical regions. One of the most functionally important and ecologically dominant animal groups in these environments is the ants. Here, we quantify the overall impacts of clear-felling lowland dipterocarp rainforest and conversion into oil palm plantation on ant diversity. At study sites in Sabah, Malaysia we collected ants from three microhabitats: 1 – the canopy, 2 – bird's nest ferns (Asplenium nidus complex, a common epiphyte in forest and oil palm), and 3 – leaf litter. We also measured temperature, humidity and light at collection sites to assess their impacts on ant community composition. Total ant species richness decreased from 309 to 110 (?64%) between forest and oil palm plantation. However, this impact was not the same across all microhabitats, with bird's nest ferns maintaining almost the same number of ant species in oil palm compared to forest (forest-oil palm, ferns: 36–35 (3% loss), canopy: 120–58 (52% loss), leaf litter: 216–56 (74% loss)). Relative abundance distributions remained the same for fern-dwelling ants, but became less even for oil palm ants in both the canopy and the leaf litter. These differences may be due in part to the ability of bird's nest ferns to provide a stable microclimate in hot, dry plantations. We also found that non-native ant species were more abundant in oil palm than in forest, and few forest ant species survived in plantations in any of the microhabitats. Only 59 of the 309 forest species persisted in oil palm plantations, corresponding to an 81% loss of forest species resulting from habitat conversion. Although oil palm supports many more ant species than has been previously reported, converting forest into plantation still leads to a dramatic reduction in species richness. The maintenance of forested areas is therefore vital for the conservation of ant biodiversity.  相似文献   

4.
Brieftauben     
Homing pigeons Homing pigeons are well known for their excellent homing abilities which allow them to return to their lofts from unknown releasing sites more than hundreds of kilometres away. Several orientation mechanisms – sun compass, earth's magnetic field, olfactory cues, visual cues – are known to be involved in homing performance as well as parameters such as motivation and experience. New technology give an insight in their homing behaviour and track preferences and it is shown that homing pigeons physiology and neurobiology seem to be functionally adapted to homing. Pigeons races are still common and it is shown how the pigeon breeder tries to maximize the success of his pigeons.  相似文献   

5.
Nitrogen regulates the Earth's climate system by constraining the terrestrial sink for atmospheric CO2. Proteolytic enzymes are a principal driver of the within‐system cycle of soil nitrogen, yet there is little to no understanding of their response to climate change. Here, we use a single methodology to investigate potential proteolytic enzyme activity in soils from 16 global change experiments. We show that regardless of geographical location or experimental manipulation (i.e., temperature, precipitation, or both), all sites plotted along a single line relating the response ratio of potential proteolytic activity to soil moisture deficit, the difference between precipitation and evapotranspiration. In particular, warming and reductions in precipitation stimulated potential proteolytic activity in mesic sites – temperate and boreal forests, arctic tundra – whereas these manipulations suppressed potential activity in dry grasslands. This study provides a foundation for a simple representation of the impacts of climate change on a central component of the nitrogen cycle.  相似文献   

6.
Serum Institute of India – India's top BioPharma company Biocon: Aiming for innovation leadership Rasi Seeds: Changing the face of India's bioagriculture India's iconic biotech company: Shantha Biotechnics  相似文献   

7.
《Translational oncology》2022,15(12):101233
We aimed at establishing a risk – score model using pyroptosis-related genes to predict the prognosis of patients with head and neck squamous cell carcinoma (HNSCC). A total of 33 pyroptosis-related genes were selected. We then evaluated the data of 502 HNSCC patients and 44 normal patients from TCGA database. Gene expression was then profiled to detect differentially expressed genes (DEGs). Using the univariate, the least absolute shrinkage and selection operator (LASSO) Cox regression analyses, we generated a risk – score model. Tissue samples from neoplastic and normal sites of 44 HNSCC patients were collected. qRT-PCR were employed to analyze the mRNA level of the samples. Kaplan-Meier method was used to evaluate the overall survival rate (OS). Enrichment analysis was performed to elucidate the underlying mechanism of HNSCC patient's differentially survival status from the perspective of tumor immunology. 17 genes were categorized as DEGs. GSDME, IL-6, CASP8, CASP6, NLRP1 and NLRP6 were used to establish the risk – score model. Each patient's risk score in the TCGA cohort was calculated using the risk – score formula. The risk score was able to independently predict the OS of the HNSCC patients (P = 0.02). The OS analysis showed that the risk score model (P < 0.0001) was more reliable than single gene, a phenomenon verified by practical patient cohort. Additionally, enrichment analysis indicated more active immune activities in low-risk group than high-risk group. In conclusion, our risk – score model has provided novel strategy for the prediction of HNSCC patients’ prognosis.  相似文献   

8.
The effects of electromagnetic fields (EMFs) in physiotherapy have been discussed mainly with regard to the patient's safety, while the operator's safety is neglected. This paper presents the medical assessment and specific tendencies in the health status of personnel in physical therapy wards – where the EMFs are everyday background factor. This paper summarizes the somatic part of results from the study among physiotherapy personnel from facilities with different equipment and work load by using survey card designed by us for health status screening in somatic and neurobehavioral aspects. The main specific somatic findings and complaints in investigated group include parodontosis – 42%; cardiovascular disorders – 41.6%; allergic conditions with skin or systemic manifestation – 40.8%; photosensibilization – 34.1%; skin diseases – 31.5%; musculoskeletal disorders – 30.0% and neoplasm disorders – 7.5%. Keeping in mind that better part of the personnel in the physical therapy units is female, a special attention was paid to the pathology of the reproductive system; menstrual disturbances are observed in 20.0%. These findings are collected in complex for the first time in physiotherapy personnel, and when data were available from other professional groups, we found a good correlation.  相似文献   

9.
《Translational oncology》2021,14(12):101233
We aimed at establishing a risk – score model using pyroptosis-related genes to predict the prognosis of patients with head and neck squamous cell carcinoma (HNSCC). A total of 33 pyroptosis-related genes were selected. We then evaluated the data of 502 HNSCC patients and 44 normal patients from TCGA database. Gene expression was then profiled to detect differentially expressed genes (DEGs). Using the univariate, the least absolute shrinkage and selection operator (LASSO) Cox regression analyses, we generated a risk – score model. Tissue samples from neoplastic and normal sites of 44 HNSCC patients were collected. qRT-PCR were employed to analyze the mRNA level of the samples. Kaplan-Meier method was used to evaluate the overall survival rate (OS). Enrichment analysis was performed to elucidate the underlying mechanism of HNSCC patient's differentially survival status from the perspective of tumor immunology. 17 genes were categorized as DEGs. GSDME, IL-6, CASP8, CASP6, NLRP1 and NLRP6 were used to establish the risk – score model. Each patient's risk score in the TCGA cohort was calculated using the risk – score formula. The risk score was able to independently predict the OS of the HNSCC patients (P = 0.02). The OS analysis showed that the risk score model (P < 0.0001) was more reliable than single gene, a phenomenon verified by practical patient cohort. Additionally, enrichment analysis indicated more active immune activities in low-risk group than high-risk group. In conclusion, our risk – score model has provided novel strategy for the prediction of HNSCC patients’ prognosis.  相似文献   

10.
William Simkulet 《Bioethics》2016,30(9):714-720
Recently philosophers have proposed a wide variety of interventions referred to as ‘moral enhancements’. Some of these interventions are concerned with helping individuals make more informed decisions; others, however, are designed to compel people to act as the intervener sees fit. Somewhere between these two extremes lie interventions designed to direct an agent's attention either towards morally relevant issues – hat‐hanging – or away from temptations to do wrong – hat‐hiding. I argue that these interventions fail to constitute genuine moral enhancement because, although they may result in more desirable outcomes – more altruism, more law‐following, and/or less self‐destructive behavior, they ignore a person's intentions, and often what makes an action right or wrong is the intent behind it.  相似文献   

11.
Michelle Casanova is a widely published researcher specialising in the taxonomy of Australia's freshwater algae – as well as a rural landholder who understands the need for farmers to utilise the landscape. Michelle combines her work as a researcher with increasing involvement in management and policy through her region's Catchment Management Board and Victoria's Scientific Advisory Committee.  相似文献   

12.
《Ethnic and racial studies》2012,35(6):1023-1039
Abstract

This paper explores popular representations of Barack Obama's relationship to sport during the 2008 US presidential campaign. It delineates how white normativity framed the candidate's passion for basketball and his participation in a highly publicized bowling game. We argue that Obama's athletic activities became key vehicles for reading his body and by extension his identity and his politics. The question that could only be asked in a white supremacist context – is Obama too black or not black enough to be President? – mirrored long-standing tensions in America's affective relation to black male athletes. Representations of Obama bowling further illuminate the complicated ways in which whiteness operates. The essay concludes with a brief discussion suggesting the importance of analyses of sport for ethnic and racial studies.  相似文献   

13.
Several countries have imposed bans on the wearing of face veils, a controversial option considered in Bill 94 by the province of Quebec in 2010. This paper examines non-Muslim women's support for the acceptability of the niqab in public spaces. Analysing the 2010 Quebec Women's Political Participation Survey, we find that key feminist arguments – that wearing the niqab is a woman's free choice, a matter of freedom of religion and a visible symbol of women's oppression – are important drivers of opinion. Their role in shaping opinion, however, is complex and mirrors divisions among feminist groups in the province. Additional attitudinal drivers include generation, exposure to the practice and openness to immigration. Equally important, our findings suggest that being a member of a racial minority, feelings of cultural insecurity and religiosity are of little consequence for thinking on the issue.  相似文献   

14.
China has the world's longest history of soil bioengineering, with the first mention of giant fascines to control torrential floodwaters dating from over 2000 BC. However, soil degradation on steep slopes has accelerated hugely over the last 50 years, due to poor farming practice, deforestation, road and dam construction. The central government has therefore devised a series of major programs to reduce the exploitation of forest resources (Natural Forest Protection Program – NFPP) and to rehabilitate steep slopes by encouraging the conversion of cropland to forest and orchards (Sloping Land Conversion Program – SLCP). In this review, we define soil bio- and eco-engineering and examine China's past experience in both domains. We focus on case studies whereby vegetation has been used in conjunction with civil engineering to prevent landslides in Hong Kong and the social and practical aspects of planting on steep slopes to conserve soil on a large-scale in mainland China. The successes and failures of tree planting and forest management in the NFPP and SLCP are discussed along with the priorities for future research and practical applications. This review introduces a special edition of the journal Ecological Engineering, whereby a selection of papers presented at the Second International Conference ‘Ground Bio- and Eco-engineering: The Use of Vegetation to Improve Slope Stability – ICGBE2’ held in Beijing, China, 14–18 July 2008, are published. This congress joined together scientists and practitioners with the aim of discussing new theory, methods and applications for using vegetation to fix soil on steep slopes prone to landslides and erosion. In this review, we consider the key points from the conference and place them in the context of managing and restoring degraded slopes in China, one of the world's most pertinent study sites.  相似文献   

15.
16.
This article argues for a public sociology of ‘race’ that can respond to Weber's injunction that sociology should ‘meet the demands of the day’. While the author's version of these demands – for a society of autonomous individuals and groups, living as equals – is utopian, the main argument offered here is that a sociology of ‘race’ should be a modified version of Burawoy's ‘public sociology’. Adopting Bauman's notion of a sociology of interpreters, a further suggestion is that this type of sociology needs to be reflexive and affective. Based on an analysis of his own sociological education in the late 1960s, his participation in social and political movements in which ‘race’ was key, and with brief reference to the sociology of ‘race’, the author argues that the emotions that circulated in each arena need to be examined, acknowledged and incorporated if theoretical and practical progress is to be made.  相似文献   

17.
ROB LOVERING 《Bioethics》2013,27(5):263-270
According to the theory of intrinsic value and moral standing called the ‘substance view,’ what makes it prima facie seriously wrong to kill adult human beings, human infants, and even human fetuses is the possession of the essential property of the basic capacity for rational moral agency – a capacity for rational moral agency in root form and thereby not remotely exercisable. In this critique, I cover three distinct reductio charges directed at the substance view's conclusion that human fetuses have the same intrinsic value and moral standing as adult human beings. After giving consideration to defenders of the substance view's replies to these charges, I then critique each of them, ultimately concluding that none is successful. Of course, in order to understand all of these things – the reductio charges, defenders of the substance view's replies to them, and my criticisms of their replies – one must have a better understanding of the substance view (in particular, its understanding of rational moral agency) as well as its defense. Accordingly, I address the substance view's understanding of rational moral agency as well as present its defense.  相似文献   

18.
One of Australia's leading on‐ground extension officers describes the successes and lessons learned in The Riverina's native revegetation movement over the 20–25 years – but warns of potential failure of current and future Australian revegetation programs if greater funding security is not delivered.  相似文献   

19.
Hoon Song 《Ethnos》2013,78(4):470-488
This essay dwells on the intersection of three historical contemporaries: (1) American anthropology's ‘reflexive turn’; (2) the rise of Michel Foucault's motif of ‘the gaze’ within anthropology; and (3) the spread of the aesthetics of ‘white nihilism.’ The intersection materializes in the visual trope of self-reflexivity. White nihilism, according to one account, is a self-loathing kind of reflexive gaze, preemptive of criticism and desirous of self-possession. The paper argues that Foucault's idea of the panoptic gaze had a similar effect on anthropological self-reflexivity. The essay contrasts the American reception of Foucault with the case of Francophone anthropology – including ‘the Other Foucault’ – in which self-reflexivity involves self-loss or self-division.  相似文献   

20.
Anti-Semitism in Germany has a long tradition. It dates back to religious anti-Semitism many centuries ago culminating in the Holocaust. More recently, anti-Semitism was rising again in Germany. At least partly, it was encouraged by recent news reports on the Israel-Palestine conflict. This occurred at the time when a new Anti-Semitic party – the Alternative for Germany – emerged at Germany's political scene. To ascertain the prevalence of anti-Semitism, Germany's federal parliament set up an independent commission in 2012. In 2017, the commission reported its findings. This review discusses the commission's results focusing on a definition of anti-Semitism; hate crimes based on anti-Semitism; the extend of anti-Semitism in Germany's political centre; anti-Semitism in the media, social movements and racist organizations; an evaluation of anti-Semitism based on surveys and interviews; anti-Semitism in Germany's political parties; and finally, anti-Semitism of refugees and migrants. The report concludes recommendations seeking to prevent anti-Semitism.  相似文献   

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