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51.
Steroid estrogens are thought to be the major cause of feminization (intersex) in wild fish. Widely used wastewater treatment technologies are not effective at removing these contaminants to concentrations thought to be required to protect aquatic wildlife. A number of advanced treatment processes have been proposed to reduce the concentrations of estrogens entering the environment. Before investment is made in such processes, it is imperative that we compare their efficacy in terms of removal of steroid estrogens and their feminizing effects with other treatment options. This study assessed both steroid removal and intersex induction in adult and early life stage fish (roach, Rutilus rutilus). Roach were exposed directly to either secondary (activated sludge process (ASP)), tertiary (sand filtrated (SF)), or advanced (chlorine dioxide (ClO(2)), granular activated charcoal (GAC)) treated effluents for six months. Surprisingly, both the advanced GAC and tertiary SF treatments (but not the ClO(2) treatment) significantly removed the intersex induction associated with the ASP effluent; this was not predicted by the steroid estrogen measurements, which were higher in the tertiary SF than either the GAC or the ClO(2). Therefore our study highlights the importance of using both biological and chemical analysis when assessing new treatment technologies.  相似文献   
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Presented is the case of a 37-year-old South Australian woman who experienced intractable pelvic pain following laparoscopic sterilization with Filshie clips. The pelvic anatomy was normal and one Filshie clip was applied to each Fallopian tube. The patient stated she had experienced right-sided lower abdominal pain that radiated down the anterior part of her right thigh since regaining consciousness after general anesthesia. The pain had failed to resolve seven days after the procedure and the patient was unable to perform even simple tasks. Analgesics provided only temporary, partial relief. There were no signs of infection or any other exacerbating condition. At diagnostic laparoscopy, instillation of bupivacaine around the clip provided transient relief, but the pain returned the next day at the same level of severity. After one month of intractable pain, laparoscopic bilateral salpingectomy was performed to remove the clips and the pain disappeared. Although back pain has been reported in up to 14% of women undergoing laparoscopic sterilization, this is the first published case of long-term abdominal pain associated with the Filshie clip.  相似文献   
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Turbulent flow in natural river channels drives geophysical processes and exerts a fundamental influence on aquatic biota. An extensive range of turbulence properties have previously been synthesized into four categories or “dimensions” with ecological relevance: intensity, periodicity, orientation and scale (IPOS). We apply this framework across three rivers with differing morphologies in order to assess the statistical coherence of the four IPOS categories within turbulence field data and their utility in discriminating between fundamental units of river habitat. Intensity, periodicity-scale and orientation were identified as the key gradients in the turbulence data set using multivariate analysis. These gradients all revealed statistically significant differences between rivers and/or geomorphic units. The intensity gradient accounted for the highest variance and most pronounced inter-reach differences, but the periodicity-scale and orientation gradients were also useful in distinguishing between certain combinations of rivers and/or geomorphic units. Different turbulence gradients, or combinations of gradients, were important in characterizing differences between rivers and geomorphic units (riffes, pools, steps). The gradients provided improved prediction of geomorphic units compared to standard hydraulic variables (mean velocity, depth), although the extent of improvement in prediction varied between river morphologies. The analysis reveals the statistical coherence of the four categories or “dimensions” of turbulence in multivariate space, connects the ecologically defined IPOS categories of turbulence properties with river types and fundamental units of river habitat (geomorphic units). Turbulence signatures of natural channel morphology are expressed across all four dimensions of turbulence, providing clear evidence that these four dimensions should be routinely considered in ecohydraulics and hydromorphology research to facilitate a full understanding hydraulic habitat.  相似文献   
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The paper describes the development of a tool to predict quantitatively the success of a team when executing a process. The tool was developed for the UK defence industry, though it may be useful in other domains. It is expected to be used by systems engineers in initial stages of systems design, when concepts are still fluid, including the structure of the team(s) which are expected to be operators within the system. It enables answers to be calculated for questions such as “What happens if I reduce team size?” and “Can I reduce the qualifications necessary to execute this process and still achieve the required level of success?”.The tool has undergone verification and validation; it predicts fairly well and shows promise. An unexpected finding is that the tool creates a good a priori argument for significant attention to Human Factors Integration in systems projects. The simulations show that if a systems project takes full account of human factors integration (selection, training, process design, interaction design, culture, etc.) then the likelihood of team success will be in excess of 0.95. As the project derogates from this state, the likelihood of team success will drop as low as 0.05. If the team has good internal communications and good individuals in key roles, the likelihood of success rises towards 0.25. Even with a team comprising the best individuals, p(success) will not be greater than 0.35.It is hoped that these results will be useful for human factors professionals involved in systems design.  相似文献   
56.
The effect of light quality on the performance a fixed‐film continuous‐flow photobioreactor for removal of hydrogen sulfide from synthetic industrial wastewater and conversion of it to elemental sulfur was investigated. Sixteen 150 mm long and 1.6 mm internal diameter (id) Tygon tubes formed the active part of the reactor. At the same light intensity, reactor performance in terms of optimal sulfide loading rates was compared between an infrared bulb and light emitting diodes (LEDs). The LEDs provided light within the peak absorption wavelength range of green sulfur bacteria (GSB) and were used as a light source for the GSB with the goal of reducing the cost of the required light. Though the reactor sustained higher sulfide loading rates using LEDs than when using an infrared bulb at equal light intensities, the infrared bulb has the potential to be more efficient overall. Copyright © 2004 Society of Chemical Industry  相似文献   
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Protein isolates and concentrates were obtained from defatted cashew nut powder by two methods: alkaline extraction-isoelectric precipitation (IP) and alkaline extraction-methanol precipitation (MP). The functional properties of cashew nut protein isolates, concentrates and powder were significantly different (p < 0.05). Cashew nut protein isolate (CNPI) had higher water and oil absorption capacities (2.20 ml/g and 4.42 ml/g, respectively), emulsifying stability index (447%), foam capacity and stability (45% and 55%, respectively), and least gelation capacity (13.5%) than cashew nut protein concentrate (CNPC), which was also higher than that of defatted cashew nut powder (DCNP). However, emulsifying activity index (12.45%) and bulk density (0.31) of CNPI were lower than that of CNPC, which were also lower than that of DCNP. The water solubility of CNPI (95%) and CNPC (95%) was not significantly different (p > 0.05) among the samples, but was significantly different (p < 0.05) from that of DCNP (75%). The CNPI, CNPC and DCNP showed decreasing solubility with decreasing pH, with the minimum solubility being observed at a pH range of 4.0–4.5, confirming the isoelectric point of cashew proteins. However, higher water solubility, emulsifying activity, and foaming property were observed at an alkaline pH than at an acidic pH in all samples.  相似文献   
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Several different synthetic methods have been developed to fabricate tungsten oxide (WO(3)) nanostructures, but most of them require exotic reagents or are unsuitable for mass production. In this paper, we present a systematic investigation demonstrating that arc discharge is a fast and inexpensive synthesis method which can be used to produce high quality tungsten oxide nanostructures for NO(2) gas sensing measurements. The as-synthesized WO(3) nanostructures are characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), finger-print Raman spectroscopy and proton induced x-ray emission (PIXE). The analysis shows that spheroidal-shaped monoclinic WO(3) crystal nanostructures were produced with an average diameter of 30?nm (range 10-100?nm) at an arc discharge current of 110?A and 300?Torr oxygen partial pressure. It is found that the morphology is controlled by the arc discharge parameters of current and oxygen partial pressure, e.g.?a high arc discharge current combined with a low oxygen partial pressure results in small WO(3) nanostructures with improved conductivity. Sensors produced from the WO(3) nanostructures show a strong response to NO(2) gas at 325?°C. The ability to tune the morphology of the WO(3) nanostructures makes this method ideal for the fabrication of gas sensing materials.  相似文献   
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