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11.
Tanning processes performed in drums consume large amounts of water and chemicals, most of which end up in the wastewater. This study explores an alternative approach at an industrial scale to the traditional pickle-chrome tanning method. The new method replaces formic and sulphuric acids with sulphonic aromatic acid. Because it is done without float, there is a sizeable reduction in the amount of added salt and chrome salt as well as an increase in temperatures at the end of the tanning process. From an environmental perspective, the new method offers important advantages. For instance, there is no float addition in the tannage. Also, there are reductions of 94% and 99%, respectively, in the discharge of chlorides and chrome, as well as a 75% reduction in the residual float. Our financial assessment demonstrated that the new method is 42% cheaper than a traditional approach.  相似文献   
12.
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   
13.
We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling.  相似文献   
14.
Leigh syndrome (LS) is a mitochondrial encephalopathy that is caused by a mutation either in the mitochondrial DNA (mtDNA) or in the nuclear encoded genes of the mitochondrial proteins. Prenatal diagnosis of defects in the mtDNA is usually problematic because of mtDNA heteroplasmy and tissue specificity. However, the mutations T8993 G/C in the ATP synthase subunit 6 gene of the mtDNA show a more even tissue distribution and do not appear to change significantly over time. There are only few reports of prenatal diagnosis of the T8993G mutation in Leigh disease. Here we describe the first prenatal genetic testing of T8993C in a fetus of a mother whose previous child had died of Leigh syndrome due to the T8993C mutation. Mutant load in the chorionic villus sample (CVS) as well as in amniocytes was undetectable, thus predicting a very high likelihood of an unaffected outcome, indicative of a healthy baby. The diagnosis was confirmed after birth. Gathering data on the prenatal diagnosis of mtDNA mutations is of great importance so that prenatal diagnosis of both T8993G and T8993C mutations can be offered routinely. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
15.
This study was carried out to assess the effectiveness of the combined use of earthworm (Alma millsoni) and bacterium (Bacillus sp.) in the bioremediation of spent engine oil (SEO) contaminated soils. A. millisoni were collected from the Botanical Garden of University of Ibadan, Nigeria. The stock culture of hydrocarbonoclastic Bacillus sp. was used for the bioremediation study. A set-up of eight pots containing 1000?g soil sample and 20?g of cow dung were mixed with 100, 75, 50 and 0?mL SEO respectively. Each of the set up was subjected to bioremediation agents; A. millisoni alone, Bacillus sp alone, A. millisoni and Bacillus sp, no treatment (control) in duplicate. Treatment of 100?ml SEO contaminated soil with combined A. millisoni and Bacillus sp resulted in significantly (P? bacterium > vermi-remediating agents. Earthworms exposed to 100?mLSEO-contaminated soil had higher CAT, SOD, and GPx activities compared to the control. Findings indicated that A. millisoni with Bacillus sp. can synergistically improve bioremediation of SEO contaminated soils.  相似文献   
16.
The tapered element oscillating microbalance (TEOM) system is widely used to measure continuous particle mass concentrations in air quality networks. However, the semi-volatile aerosol material is lost under normal operation conditions (50 °C). This study has evaluated the error in the organic fraction of the TEOM-measured secondary organic aerosols formed from the degradation of biogenic pollutants. Experiments were carried out under controlled, water-free conditions in a fully equipped, high volume atmospheric simulator--the European PhotoReactor (EUPHORE). The ozonolysis of α-pinene, β-pinene and limonene provided a reproducible source of organic aerosol. Particulate matter concentration profiles were registered for different TEOM operating temperatures. When these values were compared with values from a filter-based gravimetric method and a scanning mobility particle sizer (SMPS), they showed that the differences between monitoring systems increased with increasing TEOM temperature. According to our results, when the TEOM is operated at 50 °C, it fails to measure 32-46% of the organic particulate material, depending on the aerosol precursor. This study has also identified and quantified the multi-oxygenated organic compounds lost in the TEOM monitoring by using a method based on the gas chromatography-mass spectrometry technique. Important losses have been calculated for relevant ambient aerosol compounds such as pinonic acid, pinonaldehyde, norpinone and limonalic acid. In conclusion, the present study has demonstrated that a high operating temperature of the TEOM monitor reduces the humidity interference but underestimates the semi-volatile organic fraction.  相似文献   
17.
We report a fetus with hydrops, congenital heart disease and bilateral radioulnar synostosis caused by a novel pathogenic MECOM variant. The female fetus was referred for post-mortem examination after fetal hydrops and intrauterine death was diagnosed at 20 weeks gestation. Post-mortem examination confirmed fetal hydrops, pallor, truncus arteriosus and bilateral radioulnar synostosis. Trio whole genome sequencing analysis detected a novel de novo heterozygous pathogenic loss-of-function variant in MECOM (NM_004991), associated with a diagnosis of Radioulnar Synostosis with Amegakaryocytic Thrombocytopenia 2 (RUSAT-2). RUSAT-2 is a variable condition associated postnatally with bone marrow failure, radioulnar synostosis and congenital anomalies. RUSAT-2 is not currently associated with a prenatal phenotype or fetal demise, and was not present on diagnostic NHS prenatal gene panels at time of diagnosis. This case highlights the diagnostic value of detailed phenotyping with post-mortem examination, and of using a broad sequencing approach.  相似文献   
18.
Background, aim and scope The increasing use of wood for generating heat and electricity requires that more and more fuels be obtained directly or indirectly from the forest. Sound, sustainable recycling management calls for the return of any generated wood ash back to the forest to make use of the nutrients it contains. Similarly, recycling this ash in other locations such as agricultural land or private gardens can serve equally well as fertilizer. At the same time, it is critical that no accumulated pollutants be introduced into the nutrient loop. Wood ash that is heavily laden with such pollutants must not be considered for recycling. As part of this research project, commissioned by the Ministry for the Environment and Conservation, Agriculture and Consumer Protection of the State of North Rhine-Westphalia in Germany (MUNLV), ash samples of 209 wood-fired appliances generating between 10 and 4000?kW of heat performance were taken from throughout the federal state of North Rhine-Westphalia. Untreated wood, either forested or scrap, was used as the sole fuel for these appliances. Materials and methods All course ash and fly ash samples were analyzed to determine their composition of main nutrients, heavy metals, and the elements Fe, Cl, Si, Al and Na. The purpose of this analysis was to evaluate the suitability of this wood ash for reintroduction to forest soils or as fertilizer in other types of soil. Results The majority of the wood ash samples in this study contained sufficiently high amounts of nutrients to match the requirement for stand-alone fertilizers (PK-fertilizer, potash fertilizer). However, the heavy metal content was highly variable, with a mean content high enough to prohibit them from being classified per se as PK- or potash fertilizer for agricultural land. Due to the high quantities of cadmium, application of this ash to garden soils would likewise be ill-advised. Discussion On forest soils German law permits application of a mixture of potash fertilizer containing, at most, 30?% wood ash (course ash). Because of the high amounts of cadmium and copper, wood ash from our samples can only comprise a maximum of 28?% when added to typically used potash fertilizers. Higher percentage of wood ash would exceed the cut-off value established by the German Fertilizer Ordinance (Düngemittelverordnung – DüMV). Conclusions The application of wood ash on agricultural land and in private gardens is, rightfully so, highly regulated by law. However, the rules governing application of wood ash in the forest are much more lax. Determination of heavy metal content in wood ash cannot be used to determine compliance with DüMV standards because of the high content and fluctuating nature of heavy metals found. Recommendations and perspectives Presently an alternative approach for classifying the ecologic risk of wood ash recycling is being developed.  相似文献   
19.
Fluoride is a naturally occurring toxic mineral present in drinking water and causes yellowing of teeth, tooth problems etc. Fluorspar, Cryolite and Fluorapatite are the naturally occurring minerals, from which fluoride finds its path to groundwater through infiltration. In the present study two groundwater samples, Station I and Station II at Hyderabad megacity, the capital of Andhra Pradesh were investigated for one year from January 2001 to December 2001. The average fluoride values were 1.37 mg/l at Station I and 0.91 mg/l at Station II. The permissible limit given by BIS (1983) 0.6-1.2 mg/l and WHO (1984) 1.5 mg/l for fluoride in drinking water. The groundwaters at Station I exceeded the limit while at Station II it was within the limits. The study indicated that fluoride content of 0.5 mg/l is sufficient to cause yellowing of teeth and dental problems.  相似文献   
20.
Using multiwave survey data collected among 251 financial sales professionals, we tested whether involuntarily working more from home (teleworking) was related to higher time‐based and strain‐based work‐to‐family conflict (WFC). Employees' boundary management strategy (integration vs. segmentation) and work–family balance self‐efficacy were considered as moderators of these relationships. Data were collected one month before, three months after, and 12 months after the implementation of a new cost‐saving policy that eliminated employees' access to office space in a centralized work location. The policy resulted in employees being forced to work more from home. A voluntary telework program had been in effect before the new policy, implying that working more from home as a result of the new policy was involuntary in nature. Results revealed that involuntarily working more from home was associated with higher strain‐based WFC but not higher time‐based WFC. However, moderator analyses revealed that the positive association between involuntarily working more from home and both types of WFC was significantly stronger among employees with weaker self‐efficacy in balancing work and family. Boundary management strategy had no detectable moderating effect. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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