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1.
The article explores a popular volunteer movement in Thailand and its connection to Buddhist morality and contemporary Thai politics. The article argues that volunteering in Thailand is often conceived of as a gift in various ways: as a form of dana or selfless giving; a gift from ‘good people’ to those defined as ‘in need’ in society and a gift to the Thai nation as a whole. Indeed, when volunteering is said to be a gift to the Thai nation, it is not necessarily because of its ability to redistribute resources, but because of its perceived ability to cultivate moral values and ‘good people’ for the Thai nation. The paper explores the implications that stem from presenting volunteering as a gift, with a strong emphasis on morality and ‘good people’, and how this popular discourse on volunteering may contribute to the maintenance of political status quo in Thailand, particularly in the context of the ongoing political struggles in recent years.  相似文献   

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Edward O. Wilson's forays into human sociobiology have been the target of persistent, vehement attack by his Harvard colleague in evolutionary biology, Richard C. Lewontin. Through examination of existing documents in the case, together with in-depth personal interviews of Wilson, Lewontin, and other biologists, the reasons for Wilson's stance and Lewontin's criticisms are uncovered. It is argued that the dispute is not primarily personally or politically motivated, but involves a conflict between long-term scientific-cum-moral agendas, with the reductionist program as a key issue. It is concluded that it is in the interest of both disputants to keep the controversy alive.  相似文献   

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Summary The parenchyma of the normal resting human breast was examined by electron microscopy to characterize the cells undergoing mitosis and the mechanism by which the normal tissue architecture is maintained during this process. In this study of 112 mitotic cells, it was found that the mitotic cells were luminally positioned, polarised epithelial cells with no evidence of myoepithelial cell division. Ultrastructurally, the nuclear and cytoplasmic changes were consistent with previous reports of mitosis in other tissues. However, unlike all previous reports, two specific orientations of the nuclear spindle and thus the planes of cytokinesis were observed. In a few cases the spindle formed parallel to the lumen and division resulted in two luminally positioned daughter cells. However, in the majority of mitotic cells the spindle was approximately at right angles to the lumen and this orientation resulted in a luminally and a basally positioned daughter cell. It is proposed that the abnormally positioned basal daughter cell could develop into a myoepithelial cell or undergo deletion (apoptosis). Thus the two orientations of mitosis may explain the mechanism by which the epithelial and myoepithelial cell populations were maintained by a single progenitor cell without disrupting the integrity of the tissue architecture.  相似文献   

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Upper venous system anatomic variations may cause difficulties during cardiac pacemaker implantation. Persistent left superior vena cava (PLSVC) and absent right superior vena cava could be an arrhythmogenic source of atrial arrhythmias and cardiac conduction disease. We represent dual-chamber pacemaker implantation in a patient with a very rare upper venous system anomaly, paroxysmal atrial fibrillation, sick sinus syndrome, that cause unusual fluoroscopic image.  相似文献   

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The findings reported here form part of a larger research project that examined non-compliance with medication among the mentally ill patients attending public clinics in a specific parish in Jamaica. The aim of the research was to explore the perceptions of caregivers about caring for the mentally ill at two outpatient psychiatric clinics. Caregivers involved in looking after their relatives with mental illness played a vital role in mental health promotion. This study sought to examine the caregivers'' perception of mental illness, including how they thought the illness was best controlled, the reasons why their relatives found it difficult to take their medication as instructed, and the coping skills that they employed when caring for their relatives. There were two focus groups, consisting of four individuals each, at two psychiatric clinics.The results revealed the following about the majority of the caregivers. First, it was recognised that caregivers have a good knowledge (and awareness) of medication usage inferred by either the absence or the presence of their relatives'' symptoms. Secondly, they sometimes felt sad and hopeless as a result of being the victims of violent attacks by those for whom they provided care. Thirdly, they highlighted issues of cost, accessibility and availability of medications as being problematic. Fourthly, in some cases they received little or no assistance from other family members.  相似文献   

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This study reports the persistence of axis-like structures in the centromeric region of both homologues during the metaphase-I and anaphase-I stages of meiotic division of mouse spermatocytes. A novel type of silver argentaffin technique (NH4–Ag) is employed. This technique includes the treatment of glutaraldehyde-fixed tissues with dilute ammonium hydroxide followed by a reduction of aldehyde groups with sodium borohydride. Staining is accomplished with ammoniacal silver nitrate in darkness followed by sulfite washing. The lateral elements of synaptonemal complexes and the single chromosomal axes of diplotene spermatocytes show a prominent reactivity with this technique. The pattern of very small grains over condensed chromatin is uniform and gives only a light opacity to the electron beam. The presence of an axis-like structure is seen in every centromeric end of meiotic chromosomes at metaphase I and anaphase I. The chromatin (heterochromatin) that surrounds the centromeric filament and some material distributed in irregular linear arrays along some of the homologues also showed a higher electron opacity than the bulk of deoxyribonucleoprotein. While the former is related to C+ heterochromatin, the latter could represent dispersed material of diplotene axes. It is suggested that the disposal of axial material is differentially delayed at the centromeric regions. The present evidence supports the hypothesis that axial fragments or lateral-element segments persisting at these regions contribute to the cohesiveness of centromeres of sister chromatids during normal disjunction.  相似文献   

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As El Niño is predicted to become stronger and more frequent in the future, it is crucial to understand how El Niño-induced droughts will affect tropical forests. Although many studies have focused on tropical rainforests, there is a paucity of studies on seasonally dry tropical forests (SDTFs), particularly in Asia, and few studies have focused on seedling dynamics, which are expected to be strongly affected by drought. Seedlings in SDTFs are generally more drought-tolerant than those in the rainforests, and the effects of El Niño-induced droughts may differ between SDTF and tropical rainforests. In this study, we explored the impact of El Niño-induced drought at an SDTF in northern Thailand by monitoring the seedling dynamics at monthly intervals for 7 years, including a period of strong El Niño. The effects were compared between two forest types in an SDTF: a deciduous dipterocarp forest (DDF), dominated by deciduous species, and an adjacent lower montane forest (LMF) with more evergreen species. El Niño-induced drought increased seedling mortality in both the forest types. The effect of drought was stronger in evergreen than in the deciduous species, resulting in higher mortality in the LMF during El Niño. However, El Niño increased seedling recruitment only in the DDF, mainly because of the massive recruitment of the deciduous oak, Quercus brandisiana (Fagaceae), which compensated for the mortality of seedlings in the DDF. As a result, El Niño increased seedling density in the DDF and decreased it in the LMF. This is the first long-term study to identify the differences in the impacts of El Niño on seedlings between the two forest types, and two leaf habits, evergreen and deciduous, in Southeast Asia. Our findings suggest that future climate change may alter the species composition and spatial distribution of seedlings in Asian SDTFs.  相似文献   

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State governments in China have laid down laws for protecting rare and endangered species, but the effective protection depends on accurate species identification. Although DNA fingerprinting has appeared in court as legal evidence for many years, it is unsuitable for species identification as previous multilocus probes produce individual-specific fingerprints. This study outlines the development of a new species-specific probe – the pta2 probe. Using this oligonucleotide probe, the identification of all deer species in China is made possible by species-specific fingerprints. Material evidence can then be provided to any judicial organization, which will have a profound effect on the criminal activities of poachers, thereby helping to protect wild animals and conserve biodiversity. Interestingly, the pta2 probe can also reveal the gender of detected deer species.  相似文献   

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Two distinct classes of protein referred to as short- and long-lived (Poole and Wibo, 1973) were found in pulse-chased HeLa S-3 and BHK 21/C13 cells. From experiments with pulse times ranging from 1 min to 20 h, a clear inverse correlation emerged between the pulse length and the percentage of protein which was hydrolysed intracellularly in the first h of chase. Using a 5 min pulse labelling with 3H-leucine, cells were either harvested immediately or after a 2 h chase. Approximately 35% of the label incorporated by cells was lost in a 2h chase; however, electrophoretic separation of cytosol and residual cytoplasmic fractions revealed no significant alteration in their protein profiles. The technique of selectively labelling ‘short’ and ‘long-lived’ proteins, which implies qualitative differences between them, is more readily interpreted as an artificial polarisation of a declining statistical probability curve of proteolysis with time which is similar for all nascent proteins.  相似文献   

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Predicting which species are likely to cause serious impacts in the future is crucial for targeting management efforts, but the characteristics of such species remain largely unconfirmed. We use data and expert opinion on tropical and subtropical grasses naturalised in Australia since European settlement to identify naturalised and high-impact species and subsequently to test whether high-impact species are predictable. High-impact species for the three main affected sectors (environment, pastoral and agriculture) were determined by assessing evidence against pre-defined criteria. Twenty-one of the 155 naturalised species (14%) were classified as high-impact, including four that affected more than one sector. High-impact species were more likely to have faster spread rates (regions invaded per decade) and to be semi-aquatic. Spread rate was best explained by whether species had been actively spread (as pasture), and time since naturalisation, but may not be explanatory as it was tightly correlated with range size and incidence rate. Giving more weight to minimising the chance of overlooking high-impact species, a priority for biosecurity, meant a wider range of predictors was required to identify high-impact species, and the predictive power of the models was reduced. By-sector analysis of predictors of high impact species was limited by their relative rarity, but showed sector differences, including to the universal predictors (spread rate and habitat) and life history. Furthermore, species causing high impact to agriculture have changed in the past 10 years with changes in farming practice, highlighting the importance of context in determining impact. A rationale for invasion ecology is to improve the prediction and response to future threats. Although our study identifies some universal predictors, it suggests improved prediction will require a far greater emphasis on impact rather than invasiveness, and will need to account for the individual circumstances of affected sectors and the relative rarity of high-impact species.  相似文献   

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The reef coral Goniastrea aspera is regarded as one of the most environmentally tolerant species on Indo-Pacific reefs. Its demise, following a severe bleaching event in the Andaman Sea in the north-eastern Indian Ocean in 2010, was surprising in view of the rapid recovery of co-existing species such as Porites lutea. Demographic studies of G. aspera at this site showed the population was mainly composed of large individuals, which recruited in the early 1990s. These results, and size-specific mortality observed in G. aspera, post-bleaching, suggest that factors, related to size and age, may have contributed to the coral’s marked decline.  相似文献   

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Following a strategy similar to that used in baker’s yeast (Herrgård et al. Nat Biotechnol 26:1155–1160, 2008). A consensus yeast metabolic network obtained from a community approach to systems biology (Herrgård et al. 2008; Dobson et al. BMC Syst Biol 4:145, 2010). Further developments towards a genome-scale metabolic model of yeast (Dobson et al. 2010; Heavner et al. BMC Syst Biol 6:55, 2012). Yeast 5—an expanded reconstruction of the Saccharomyces cerevisiae metabolic network (Heavner et al. 2012) and in Salmonella typhimurium (Thiele et al. BMC Syst Biol 5:8, 2011). A community effort towards a knowledge-base and mathematical model of the human pathogen Salmonella typhimurium LT2 (Thiele et al. 2011), a recent paper (Thiele et al. Nat Biotechnol 31:419–425, 2013). A community-driven global reconstruction of human metabolism (Thiele et al. 2013) described a much improved ‘community consensus’ reconstruction of the human metabolic network, called Recon 2, and the authors (that include the present ones) have made it freely available via a database at http://humanmetabolism.org/ and in SBML format at Biomodels (http://identifiers.org/biomodels.db/MODEL1109130000). This short analysis summarises the main findings, and suggests some approaches that will be able to exploit the availability of this model to advantage.  相似文献   

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A multiproxy record comprising pollen, charcoal, loss on ignition and particle size analyses from two radiocarbon dated sediment cores from Klong Kone subdistrict on the western coast of the Gulf of Thailand provides insights on mangrove dynamics, environmental changes and human activities during the last 800 years. The mangroves were dominated by Rhizophora which indicates that the area has been influenced by the sea level from at least 820 cal bp until 720 cal bp. An intertidal area may have formed that supported mangrove development as part of an old shoreline during 820–720 cal bp. After 720 cal bp, mangroves decreased and were replaced by grasses, suggesting that a lower sea level caused the mangroves to grow closer to the sea until around 140 cal bp. Cereal pollen increased from 720 cal bp suggesting probable use of the shoreline for intensive cultivation. The mangroves were characterised by Avicennia, which increased toward the top of the 2 cores, suggesting that the mangroves then grew further inland, probably due to recent sea-level rise. Intensive human activity is recorded during the 20th century, as indicated by increased particle size, charcoal and carbonate content. At present, human activity in the area includes dams and construction as well as aquaculture.  相似文献   

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A method is described for the measurement of the carbon and nitrogen content of particulate material in natural waters. Particulate material is separated by filtration through GF/C filters. The dried filter is encapsulated in silver foil using a purpose made press. Analysis is carried out using high temperature combustion with thermal conductivity detection of emission gasses. Analytical performance characteristics obtained with both standards and natural materials are given.  相似文献   

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Lynne Sigler 《Mycopathologia》1989,108(3):155-161
A woman suffering from acute tubulo-interstitial nephritis was admitted to the hospital ten days after deliberate intoxication by ingestion of Cortinarius orellanus. Orellanine, the main toxin responsible for orellanine poisoning, was detected in biological fluids and renal biopsies. It was assayed by direct spectrofluorimetry on two-dimensional thin-layer chromatograms after specific photodecomposition into orelline. The orellanine concentration was 6.12 mg/l in the plasma (10 days after ingestion). Orellanine levels in renal biopsies were 7 g per 25 mm3 of the first biopsy (13 days after ingestion) and 24 g per 8 mm3 of the second biopsy (6 months later).Taken in part from the doctorate thesis of S. Rapior.  相似文献   

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