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1.
This paper documents the meteorology and flow climatology of Amsterdam Island, a World Meteorological Organization baseline observatory located in the southern Indian Ocean. The island is strongly influenced by two meteorological systems: the subtropical anticyclone and the westerlies, known as the roaring forties. Westerly surface winds dominate ground-level flow on the island, which receives an annual average precipitation of 1100 mm. A 10-year back air trajectory climatology at 850 hPa to the island showed the same predominant westerly-southwesterly flow (55% of the period). Special emphasis was placed on trajectories that had their origin on the African continent because this was the predominant nonmarine source of trace materials that could be transported to Amsterdam Island. This transport, most frequent in the winter and early spring, coincided with the winter peak of continental radon. A comparison of trajectories and 12-h precipitation amounts on the island showed that most of the rain coincided with southwesterly flow, but many large individual events were frequently associated with northerly and westerly flow regimes. Meteorological information about local conditions and flow climatology is necessary to aid in the interpretation of atmospheric chemistry measurements made at global stations such as Amsterdam Island.  相似文献   

2.
Congenital CMV infection (cCMV) is the most prevalent congenital infection, main non-genetic cause of sensorineural hearing loss (SNHL) and major cause of neurological disability. Despite the burden of cCMV, no Public Health body recommends universal serology screening in pregnancy. This was explained by gaps in knowledge of epidemiology, diagnosis, prognosis and the absence of any validated treatment. Over 10 years, progress has been made in our understanding of cCMV following primary maternal infection. Risk factors have been identified and quantified, notably it is now well recognized that among maternal primary infections only those occurring in the first trimester may lead to long-term sequelae. Algorithms combining IgG, IgM, and IgG avidity detection with serological assays adapted on high throughput platforms have demonstrated high sensitivity and specificity to diagnose maternal primary infection. The prognostic value of prenatal imaging combining ultrasound and MRI has been validated by many studies. Finally, recent data from a randomized controlled study demonstrated the efficacy of early antiviral therapy to prevent vertical transmission. Whether CMV serology screening in the first trimester of pregnancy meets the WHO's criteria for a screening program will therefore be reviewed.  相似文献   

3.
The study aims to assess the commercial viability of a potential crop insurance market in Bangladesh. In a large scale household survey, agricultural farm households were asked for their preferences for a hypothetical crop insurance scheme using double bounded (DB) contingent valuation (CV) method. Both revenue and production cost based indemnity payment approaches were applied to assess the commercial viability of a crop insurance program assuming a partner-agent (PA) model of insurance supply. Crop insurance is found marginally commercially viable in riverine flood plain areas. The expected indemnity payable consistently exceeds the expected insurance premium receivable by the insurer for the households living in wetland basin and coastal floodplain. We conclude that a uniform structure of crop insurance market does not exist in Bangladesh. The nature of the disaster risks faced by the farm households and the socio-economic characteristics of the rural farm communities need to be taken into careful consideration while designing such an insurance scheme.
Sonia AkterEmail:
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4.
5.
Unlike natural selection, phenotypic plasticity allows organisms to respond quickly to changing environmental conditions. However, plasticity may not always be adaptive. In insects, body size and other morphological measurements have been shown to decrease as temperature increases. This relationship may lead to a physiological conflict in ants, where larger body size and longer legs often confer better thermal resistance. Here, we tested the effect of developmental temperature (20, 24, 28 or 32 °C) on adult thermal resistance in the thermophilic ant species Aphaenogaster senilis. We found that no larval development occurred at 20 °C. However, at higher temperatures, developmental speed increased as expected and smaller adults were produced. In thermal resistance tests, we found that ants reared at 28 and 32 °C had half-lethal temperatures that were 2 °C higher than those of ants reared at 24 °C. Thus, although ants reared at higher temperatures were smaller in size, they were nonetheless more thermoresistant. These results show that A. senilis can exploit phenotypic plasticity to quickly adjust its thermal resistance to local conditions and that this process is independent of morphological adaptations. This mechanism may be particularly relevant given current rapid climate warming.  相似文献   

6.
Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detroit water (Lake Huron) with corrosion control, to Flint River water without corrosion control. Although lead levels are now closer to normal, reports of skin rashes have sparked questions surrounding tap water in some Flint homes. This study investigated the presence of contaminants, including disinfection by-products (DBPs), in the hot tap water used for showering in the homes of residents in Flint. Extensive quantitative analysis of 61 regulated and priority unregulated DBPs was conducted in Flint hot and cold tap water, along with the analysis of 50 volatile organic compounds and a nontarget comprehensive, broadscreen analysis, to identify a possible source for the reported skin rashes. For comparison, chlorinated hot and cold waters from three other cities were also sampled, including Detroit, which also uses Lake Huron as its source water. Results showed that hot water samples generally contained elevated levels of regulated and priority unregulated DBPs compared to cold water samples, but trihalomethanes were still within regulatory limits. Overall, hot shower water from Flint was similar to waters sampled from the three other cities and did not have unusually high levels of DBPs or other organic chemicals that could be responsible for the skin rashes observed by residents. It is possible that an inorganic chemical or microbial contaminant may be responsible.  相似文献   

7.
We conducted a comprehensive evidence-based review on the epidemiology and current standard of care of gastroschisis management as well as the pathophysiology, rationale and feasibility of fetal therapy as a viable alternative. Gastroschisis is a periumbilical abdominal wall defect characterized by abdominal viscera herniation in utero. It affects 4 in 10 000 live births, but the prevalence has steadily increased in recent years. Gastroschisis is typically diagnosed on routine second-trimester ultrasound. The overall prognosis is favorable, but complex gastroschisis, which accounts for about 10% to 15% of cases, is associated with a higher mortality, significant disease burden and higher healthcare costs due to long- and short-term complications. The current standard of care has yet to be established but generally involves continued fetal surveillance and multidisciplinary perinatal care. Postnatal surgical repair is achieved with primary closure, staged silo closure or sutureless repair. Experimental animal studies have demonstrated the feasibility of in utero closure, antiinflammatory therapy and prenatal regenerative therapy. However, reports of early preterm delivery and amnioinfusion trials have failed to show any benefit in humans. Further experimental studies and human trials are necessary to demonstrate the potential benefit of fetal therapy in gastroschisis.  相似文献   

8.
Waterborne exposure to human viruses through contact with sewage-contaminated water environments can result in infections associated with a wide range of illnesses. Gastrointestinal symptoms are the most commonly encountered manifestations of waterborne viral illness. Respiratory diseases, neurological diseases and paralysis can also occur. Whether viral infections resulting in health outcomes like cancer might also be transmitted by the waterborne route is unknown. Recently, viruses belonging to two oncogenic groups—Human Papillomaviruses (HPVs) and Human Polyomaviruses (HPyVs)—have been detected in urban sewages worldwide. The latter have also been identified in other water environments. HPVs are epitheliotropic viruses responsible for several diseases of skin and mucosae, from common warts to squamous intraepithelial lesions that can either heal or progress to invasive carcinoma of the cervix, vulva, vagina, penis, anus or oropharynx. Human PyVs infect different tissues and organs, causing infections that are usually subclinical in immunocompetent individuals but can be serious in immunocompromised hosts. These pathogens belong to a family of DNA tumour viruses. Merkel cell polyomavirus, a HPyV identified in recent years, has attracted much attention due to its link with a rare and aggressive form of human cancer. Merkel cell carcinoma, the incidence of which has tripled over the past two decades. JC polyomavirus and BK polyomavirus are also potentially oncogenic. The observed abundance and wide dissemination of HPVs and HPyVs in water environments strongly suggest the need to shed light on the fate of these viruses in water environments and to elucidate their potential for waterborne transmission. Such information is essential for the improvement of wastewater management programs in terms of both sewage treatment and water quality surveillance.  相似文献   

9.
10.
Early pregnancy renal anhydramios (EPRA) comprises congenital renal disease that results in fetal anhydramnios by 22 weeks of gestation. It occurs in over 1 in 2000 pregnancies and affects 1500 families in the US annually. EPRA was historically considered universally fatal due to associated pulmonary hypoplasia and neonatal respiratory failure. There are several etiologies of fetal renal failure that result in EPRA including bilateral renal agenesis, cystic kidney disease, and lower urinary tract obstruction. Appropriate sonographic evaluation is required to arrive at the appropriate urogenital diagnosis and to identify additional anomalies that allude to a specific genetic diagnosis. Genetic evaluation variably includes karyotype, microarray, targeted gene testing, panels, or whole exome sequencing depending on presentation. Patients receiving a fetal diagnosis of EPRA should be offered management options of pregnancy termination or perinatal palliative care, with the option of serial amnioinfusion therapy offered on a research basis. Preliminary data from case reports demonstrate an association between serial amnioinfusion therapy and short-term postnatal survival of EPRA, with excellent respiratory function in the neonatal period. A multicenter trial, the renal anhydramnios fetal therapy (RAFT) trial, is underway. We sought to review the initial diagnosis ultrasound findings, genetic etiologies, and current management options for EPRA.  相似文献   

11.
12.
Neanderthals disappeared sometime between 30,000 and 24,000?years ago. Until recently, Neanderthals were understood to have been predominantly meat-eaters; however, a growing body of evidence suggests their diet also included plants. We present the results of a study, in which sequential thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) were combined with morphological analysis of plant microfossils, to identify material entrapped in dental calculus from five Neanderthal individuals from the north Spanish site of El Sidrón. Our results provide the first molecular evidence for inhalation of wood-fire smoke and bitumen or oil shale and ingestion of a range of cooked plant foods. We also offer the first evidence for the use of medicinal plants by a Neanderthal individual. The varied use of plants that we have identified suggests that the Neanderthal occupants of El Sidrón had a sophisticated knowledge of their natural surroundings which included the ability to select and use certain plants.  相似文献   

13.
The expectations on protected areas to deliver not only biodiversity conservation but also to provide an array of different ecosystem services rise. Sequestration and storage of carbon are promising services that protected areas may provide. This study integrates spatially explicit data on terrestrial Natura 2000 sites, soil organic carbon, and agricultural land values to estimate the potential for climate-smart conservation planning in the European Union. The objectives of this study are to analyse spatial relations between protected areas soil carbon content, and land values on the European Union's land area as well as to locate and quantify the proportion of land with high carbon and low economic value within and outside protected areas. We apply a unique interdisciplinary framework with methods ranging from analyses based on geographical information systems, agricultural economics to statistics. Findings indicate that there is a significant overlap between Natura 2000 sites and regions with high carbon content across Europe. Statistical analyses show that carbon-rich regions have significantly lower land values than other areas. Our results suggest that biodiversity protection and mitigation of climate change through conservation of soil carbon could be simultaneously achieved in Europe's protected areas and beyond. We conclude that there is a notable potential for climate-smart conservation in Europe that needs further investigation.  相似文献   

14.

Objectives

The aim of this study was to evaluate the role of fetal magnetic resonance imaging (MRI) as a complement to ultrasound (US) in the prenatal diagnosis of craniofacial anomalies.

Methods

A historical cohort study including all pregnant women who were referred for fetal MRI because of antenatal diagnosis of craniofacial anomalies on screening US. Prenatal diagnostic US, MRI, and postnatal diagnosis were compared for consistencies and discrepancies.

Results

Forty-five pregnant women with 73 suspected fetal craniofacial anomalies diagnosed by US underwent MRI. In 40 out of 73 anomalies (54.8%), US and MRI findings were in complete agreement with postnatal diagnoses. MRI correctly ruled out the diagnosis of 24 anomalies suspected on US and diagnosed four additional pathologies that were not demonstrated by US. Out of the 85 anomalies (suspected by imaging or confirmed postnatally), confident diagnosis could be made by MRI in 68 anomalies (80%), not diagnosed in 10 (11.8%), and over-diagnosed in seven (8.2%). By US, confident diagnosis could be made in 44 anomalies (51.8%), not diagnosed in 11 (12.9%), and over-diagnosed in 30 (35.3%).

Conclusion

MRI is valuable in the antenatal evaluation of fetal craniofacial anomalies and may be useful as an adjunct to US in the prenatal work-up of craniofacial anomalies.  相似文献   

15.

Objectives

To give an overview of the genetic and structural abnormalities occurring in fetuses with nuchal translucency (NT) measurement exceeding the 95th percentile at first-trimester screening and to investigate which of these abnormalities would be missed if cell-free fetal DNA (cfDNA) were used as a first-tier screening test for chromosomal abnormalities.

Methods

This is a national study including 1901 pregnancies with NT≥95th percentile referred to seven university hospitals in the Netherlands between 1 January 2010 and 1 January 2016. All cases with unknown pregnancy outcome were excluded. Results of detailed ultrasound examinations, karyotyping, genotyping, pregnancy and neonatal outcomes, investigation by a clinical geneticist and post-mortem investigations were collected.

Results

In total, 821 (43%) pregnancies had at least one abnormality. The rate of abnormalities was 21% for fetuses with NT between 95th and 99th percentile and 62% for fetuses with NT≥99th percentile. Prevalence of single-gene disorders, submicroscopic, chromosomal and structural abnormalities was 2%, 2%, 30% and 9%, respectively.

Conclusion

Although cfDNA is superior to the combined test, especially for the detection of trisomy 21, 34% of the congenital abnormalities occurring in fetuses with increased NT may remain undetected in the first trimester of pregnancy, unless cfDNA is used in combination with fetal sonographic assessment, including NT measurement.  相似文献   

16.
Since the completion of the Management of Myelomeningocoele Study, maternal-fetal surgery for spina bifida has become a valid option for expecting parents. More recently, multiple groups are exploring a minimally invasive approach and recent outcomes have addressed many of the initial concerns with this approach. Based on a previously published framework, we attempt to delineate the developmental stage of the surgical techniques. Furthermore, we discuss the barriers of performing randomized controlled trials comparing two surgical interventions and suggest that data collection through registries is an alternative method to gather high-grade evidence.  相似文献   

17.
Bacteria thriving in underground systems, such as karsts, adapt to use a variety of nutrients. Most of these nutrients derive from superficial processes. This study shows that bacteria are able to differentially induce carbonate precipitation or dissolution depending on the availability of nutrients for growth. Different bacterial strains isolated from caves, representing the most common components of these microbial communities, were cultured with different carbon and nitrogen sources (e.g., acetate, glucose, peptone, humic acids) and induced changes in pH were measured during growth. Carbonate can either precipitate or dissolve during bacterial growth. The induction of carbonate precipitates or their dissolution as a function of consumption of specific carbon sources revealed the existence of an active nutrient cycling process in karsts and links nutrients and environmental conditions to the existence of a highly significant carbon sink in subterraneous environments.  相似文献   

18.
We present a general framework to plan for sustainability and then relate it to some well-known tools for sustainable development. This framework follows from principles for how a system is constituted (ecological and social principles), and contains principles for a favorable outcome for the system (sustainability), as well as principles for the process to reach this outcome (sustainable development). The principles for sustainability define the favorable outcome and direct problem-solving upstream towards problemsources. A program of activities is then constructed by backcasting from defined outcomes to the current problems. This is followed by “metrics”, i.e. various concepts for measuring and monitoring the activities. Most concepts and tools for sustainable development function as metrics, for instance life cycle assessment (LCA), ecological footprinting (EF), and Factor X. An environmental management system (EMS), like ISO 14001 or EMAS, is an administrative vehicle that should systematically align a firm's specific outcomes, activities and metrics with a general framework for sustainability. From a strategic point of view, metrics should measure alignment of activities with the principles contained in a framework for sustainability. A framework is not an alternative to concepts and tools for metrics. We need them all, because they represent different interrelated levels of strategic planning.  相似文献   

19.
Nanotechnology has the potential for the development of new materials and processes that can substitute for toxic materials now used in industry. Excitement over this possibility is tempered, however, by the potential adverse environmental health and safety aspects of the new nanomaterials. Although a few examples from the literature are encouraging, e.g., wire and cable insulation, great care must be taken to perform complete alternatives assessment evaluations of any new nanotechnology-enabled product before its adoption.  相似文献   

20.
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