Sensible heat has significantly affected the global hydrological cycle over the historical period

Globally, latent heating associated with a change in precipitation is balanced by changes to atmospheric radiative cooling and sensible heat fluxes. Both components can be altered by climate forcing mechanisms and through climate feedbacks, but the impacts of climate forcing and feedbacks on sensible heat fluxes have received much less attention. Here we show, using a range of climate modelling results, that changes in sensible heat are the dominant contributor to the present global-mean precipitation change since preindustrial time, because the radiative impact of forcings and feedbacks approximately compensate. The model results show a dissimilar influence on sensible heat and precipitation from various drivers of climate change. Due to its strong atmospheric absorption, black carbon is found to influence the sensible heat very differently compared to other aerosols and greenhouse gases. Our results indicate that this is likely caused by differences in the impact on the lower tropospheric stability

Harvesting Electricity with Geobacter bremensis Isolated from Compost

Electrochemically active (EA) biofilms were formed on metallic dimensionally stable anode-type electrode (DSA), embedded in garden compost and polarized at +0.50 V/SCE. Analysis of 16S rRNA gene libraries revealed that biofilms were heavily enriched in Deltaproteobacteria in comparison to control biofilms formed on non-polarized electrodes, which were preferentially composed of Gammaproteobacteria and Firmicutes. Among Deltaproteobacteria, sequences affiliated with Pelobacter and Geobacter genera were identified. A bacterial consortium was cultivated, in which 25 isolates were identified as Geobacter bremensis. Pure cultures of 4 different G. bremensis isolates gave higher current densities (1400 mA/m2 on DSA, 2490 mA/m2 on graphite) than the original multi-species biofilms (in average 300 mA/m2 on DSA) and the G. bremensis DSM type strain (100–300 A/m2 on DSA; 2485 mA/m2 on graphite). FISH analysis confirmed that G. bremensis represented a minor fraction in the original EA biofilm, in which species related to Pelobacter genus were predominant. The Pelobacter type strain did not show EA capacity, which can explain the lower performance of the multi-species biofilms. These results stressed the great interest of extracting and culturing pure EA strains from wild EA biofilms to improve the current density provided by microbial anodes

Hospitalizations for acetaminophen overdose: a Canadian population-based study from 1995 to 2004

<p>Abstract</p> <p>Background</p> <p>Acetaminophen overdose (AO) is the most common cause of acute liver failure. We examined temporal trends and sociodemographic risk factors for AO in a large Canadian health region.</p> <p>Methods</p> <p>1,543 patients hospitalized for AO in the Calgary Health Region (population ~1.1 million) between 1995 and 2004 were identified using administrative data.</p> <p>Results</p> <p>The age/sex-adjusted hospitalization rate decreased by 41% from 19.6 per 100,000 population in 1995 to 12.1 per 100,000 in 2004 (<it>P </it>< 0.0005). This decline was greater in females than males (46% vs. 29%). Whereas rates fell 46% in individuals under 50 years, a 50% increase was seen in those ≥ 50 years. Hospitalization rates for intentional overdoses fell from 16.6 per 100,000 in 1995 to 8.6 per 100,000 in 2004 (2004 vs. 1995: rate ratio [RR] 0.49; <it>P </it>< 0.0005). Accidental overdoses decreased between 1995 and 2002, but increased to above baseline levels by 2004 (2004 vs. 1995: RR 1.24;<it>P </it>< 0.0005). Risk factors for AO included female sex (RR 2.19; <it>P </it>< 0.0005), Aboriginal status (RR 4.04; <it>P </it>< 0.0005), and receipt of social assistance (RR 5.15; <it>P </it>< 0.0005).</p> <p>Conclusion</p> <p>Hospitalization rates for AO, particularly intentional ingestions, have fallen in our Canadian health region between 1995 and 2004. Young patients, especially females, Aboriginals, and recipients of social assistance, are at highest risk.</p

Legal Facts and Reasons for Action: Between Deflationary and Robust Conceptions of Law’s Reason-Giving Capacity

This chapter considers whether legal requirements can constitute reasons for action independently of the merits of the requirement at hand. While jurisprudential opinion on this question is far from uniform, sceptical views are becoming increasingly dominant. Such views typically contend that, while the law can be indicative of pre-existing reasons, or can trigger pre-existing reasons into operation, it cannot constitute new reasons. This chapter offers support to a somewhat less sceptical position, according to which the fact that a legal requirement has been issued can be a reason for action, yet one that is underpinned by bedrock values which law is apt to serve. Notions discussed here include a value-based conception of reasons as facts ; a distinction between complete and incomplete reasons ; and David Enoch’s idea of triggering reason-giving. Following a discussion of criticism against the view adopted here, the chapter concludes by considering some more ‘robust’ conceptions of law’s reason-giving capacity

Ants Sow the Seeds of Global Diversification in Flowering Plants

Background: The extraordinary diversification of angiosperm plants in the Cretaceous and Tertiary periods has produced an estimated 250,000–300,000 living angiosperm species and has fundamentally altered terrestrial ecosystems. Interactions with animals as pollinators or seed dispersers have long been suspected as drivers of angiosperm diversification, yet empirical examples remain sparse or inconclusive. Seed dispersal by ants (myrmecochory) may drive diversification as it can reduce extinction by providing selective advantages to plants and can increase speciation by enhancing geographical isolation by extremely limited dispersal distances. Methodology/Principal Findings: Using the most comprehensive sister-group comparison to date, we tested the hypothesis that myrmecochory leads to higher diversification rates in angiosperm plants. As predicted, diversification rates were substantially higher in ant-dispersed plants than in their non-myrmecochorous relatives. Data from 101 angiosperm lineages in 241 genera from all continents except Antarctica revealed that ant-dispersed lineages contained on average more than twice as many species as did their non-myrmecochorous sister groups. Contrasts in species diversity between sister groups demonstrated that diversification rates did not depend on seed dispersal mode in the sister group and were higher in myrmecochorous lineages in most biogeographic regions. Conclusions/Significance: Myrmecochory, which has evolved independently at least 100 times in angiosperms and is estimated to be present in at least 77 families and 11 000 species, is a key evolutionary innovation and a globally important driver of plant diversity. Myrmecochory provides the best example to date for a consistent effect of any mutualism on largescale diversification

Malaria mosquito control using edible fish in western Kenya: preliminary findings of a controlled study

<p>Abstract</p> <p>Background</p> <p>Biological control methods are once again being given much research focus for malaria vector control. This is largely due to the emerging threat of strong resistance to pesticides. Larvivorous fish have been used for over 100 years in mosquito control and many species have proved effective. In the western Kenyan highlands the larvivorous fish <it>Oreochromis niloticus </it>L. (Perciformes: Cichlidae) (formerly <it>Tilapia nilotica</it>) is commonly farmed and eaten but has not been previously tested in the field for malaria mosquito control.</p> <p>Methods</p> <p>This fish was introduced into abandoned fishponds at an altitude of 1,880 m and the effect measured over six months on the numbers of mosquito immatures. For comparison an untreated control pond was used. During this time, all ponds were regularly cleared of emergent vegetation and fish re-stocking was not needed. Significant autocorrelation was removed from the time series data, and t-tests were used to investigate within a pond and within a mosquito type any differences before and after the introduction of <it>O. niloticus</it>. Mulla's formula was also used on the raw data to calculate the percentage reduction of the mosquito larvae.</p> <p>Results</p> <p>After <it>O. niloticus </it>introduction, mosquito densities immediately dropped in the treated ponds but increased in the control pond. This increase was apparently due to climatic factors. Mulla's formula was applied which corrects for that natural tendency to increase. The results showed that after 15 weeks the fish caused a more than 94% reduction in both <it>Anopheles gambiae s.l</it>. and <it>Anopheles funestus </it>(Diptera: Culicidae) in the treated ponds, and more than 75% reduction in culicine mosquitoes. There was a highly significantly reduction in <it>A. gambiae s.l</it>. numbers when compared to pre-treatment levels.</p> <p>Conclusion</p> <p>This study reports the first field trial data on <it>O. niloticus </it>for malaria mosquito control and shows that this species, already a popular food fish in western Kenya, is an apparently sustainable mosquito control tool which also offers a source of protein and income to people in rural areas. There should be no problem with acceptance of this malaria control method since the local communities already farm this fish species.</p

Genetic polymorphisms of MDM2 and TP53 genes are associated with risk of nasopharyngeal carcinoma in a Chinese population

<p>Abstract</p> <p>Background</p> <p>The tumor suppressor TP53 and its negative regulator MDM2 play crucial roles in carcinogenesis. Previous case-control studies also revealed <it>TP53 </it>72Arg>Pro and <it>MDM2 </it>309T>G polymorphisms contribute to the risk of common cancers. However, the relationship between these two functional polymorphisms and nasopharyngeal carcinoma (NPC) susceptibility has not been explored.</p> <p>Methods</p> <p>In this study, we performed a case-control study between 522 NPC patients and 722 healthy controls in a Chinese population by using PCR-RFLP.</p> <p>Results</p> <p>We found an increased NPC risk associated with the <it>MDM2 </it>GG (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 2.08-3.96) and TG (OR = 1.49, 95% CI = 1.16-2.06) genotypes. An increased risk was also associated with the <it>TP53 </it>Pro/Pro genotype (OR = 2.22, 95% CI = 1.58-3.10) compared to the Arg/Arg genotype. The gene-gene interaction of <it>MDM2 </it>and <it>TP53 </it>polymorphisms increased adult NPC risk in a more than multiplicative manner (OR for the presence of both <it>MDM2 </it>GG and <it>TP53 </it>Pro/Pro genotypes = 7.75, 95% CI = 3.53-17.58).</p> <p>Conclusion</p> <p>The findings suggest that polymorphisms of <it>MDM2 </it>and <it>TP53 </it>genes may be genetic modifier for developing NPC.</p

Burnout and use of HIV services among health care workers in Lusaka District, Zambia: a cross-sectional study

BACKGROUND: Well-documented shortages of health care workers in sub-Saharan Africa are exacerbated by the increased human resource demands of rapidly expanding HIV care and treatment programmes. The successful continuation of existing programmes is threatened by health care worker burnout and HIV-related illness. METHODS: From March to June 2007, we studied occupational burnout and utilization of HIV services among health providers in the Lusaka public health sector. Providers from 13 public clinics were given a 36-item, self-administered questionnaire and invited for focus group discussions and key-informant interviews. RESULTS: Some 483 active clinical staff completed the questionnaire (84% response rate), 50 staff participated in six focus groups, and four individuals gave interviews. Focus group participants described burnout as feeling overworked, stressed and tired. In the survey, 51% reported occupational burnout. Risk factors were having another job (RR 1.4 95% CI 1.2-1.6) and knowing a co-worker who left in the last year (RR 1.6 95% CI 1.3-2.2). Reasons for co-worker attrition included: better pay (40%), feeling overworked or stressed (21%), moving away (16%), death (8%) and illness (5%). When asked about HIV testing, 370 of 456 (81%) reported having tested; 240 (50%) tested in the last year. In contrast, discussion groups perceived low testing rates. Both discussion groups and survey respondents identified confidentiality as the prime reason for not undergoing HIV testing. CONCLUSION: In Lusaka primary care clinics, overwork, illness and death were common reasons for attrition. Programmes to improve access, acceptability and confidentiality of health care services for clinical providers and to reduce workplace stress could substantially affect workforce stability