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101.
Hydraulic microhabitat assessment is a category of environmental flow tools (e.g., Physical Habitat Simulation system and other methodologically similar software) that, at its core, uses habitat suitability criteria (HSC) to link values of point hydraulic variables (usually depth, velocity, and substrate/cover) to habitat values for target life stages. Although this assessment tool has been used worldwide for decades, the history of the HSC curve is relatively unknown because the foundational information is predominantly contained in obscure and often unpublished reports. We review the history of the HSC concept in applied aquatic ecology to clarify its scientific pedigree, ensure its proper use, and build a foundation for future research. We begin the review with the formative decades of the 1950's through the 1970's, when consumptive‐based western USA water law conflicted with conservation traditions and natural resource management objectives, although water allocation issues date back at least to the 19th century. By analysing the history of the HSC concept, we aim to establish the biological, hydrologic, and geomorphological conditions that must be met for the HSC concept to be successfully employed. In spite of its documented assumptions and limitations, the HSC concept will likely continue to be a useful tool to help address water resources allocation issues in defined hydrologic and geomorphic settings. We conclude that HSC‐based methodologies should be considered as one of several environmental flow approaches involved in sustainable water resources management. 相似文献
102.
In this paper the swept volume with self-penetration (or self-intersection) of the cutter is presented. The complete swept volume (SV), which describes the side and bottom shape of a milling cutter undergoing self-penetration, is generated by using the Gauss map method proposed in the authors’ previous paper [Lee SW, Nestler A. Complete swept volume generation—part I: swept volume of a piecewise C1-continuous cutter at five-axis milling via Gauss map. Computer-Aided Design 2011; 43(4): 427–41]. Based on the Gauss map method, the comprehensive analysis of envelope profiles of the tool is accomplished. Through the analysis the necessary condition of the self-penetration of the cutter at five-axis movement is identified. After having classified movement types of the milling cutter in an in-depth manner, the topologically consistent boundary of SV is generated by trimming the invalid facets interior to the SV. To demonstrate the validity of the proposed method, a cutting simulation kernel for five-axis machining has been implemented and applied to cavity machining examples such as intake ports of automobile engines and so forth where the self-penetration occurs. The proposed method is proved to be robust and amenable for the practical purpose of the NC simulation. 相似文献
103.
104.
Hans-Ulrich Waiblinger Britta Boernsen Gabriele Näumann René Koeppel 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2014,9(3):297-310
The inter-laboratory (=ring-trial) validation of 4 food allergen quantification methods using real-time PCR is described. Three single real-time PCR methods for the specific detection and quantification of sesame, almond and Brazil nut were used. Additionally, a multiplex real-time PCR method combining the detection of sesame, almond, Brazil nut and lupine was tested in parallel. Matrix based calibrants (rice cookies) spiked (=incurred) with defined amounts of sesame, almond, lupine and Brazil nut were applied for quantitative evaluation. Cookies based upon wheat and rice flour as well as sauce hollandaise powder each incurred with these allergenic ingredients in the range of 10–123 milligram per kilogram were used as ring-trial samples. The lowest spike level of 10 mg/kg could reproducibly be detected by 6 of 7 PCR systems. In quantitative evaluation of the results, reproducibility standard deviations of approximately 50 % and below were obtained. In addition, the effect of the food matrix on allergen quantification was examined. The range of “recoveries” over all matrices and methods was from 43 to 109 %. 相似文献
105.
Microelectronics: Biomimetic Microelectronics for Regenerative Neuronal Cuff Implants (Adv. Mater. 43/2015) 下载免费PDF全文
106.
Burkhardt B Wittenauer J Pfeiffer E Schauer UM Metzler M 《Molecular nutrition & food research》2011,55(7):1079-1086
Scope: Monohydroxylation of alternariol (AOH) and alternariol‐9‐methyl ether (AME) has previously been reported as a prominent metabolic route under cell‐free conditions. This pathway gives rise to several catechol metabolites and may therefore be of toxicological relevance. Methods and results: To clarify whether hydroxylation of AOH and AME occurs under in vivo‐like conditions in the presence of conjugation reactions, the metabolism of the Alternaria toxins has now been studied in precision‐cut rat liver slices. Four catechol metabolites of AOH and two of AME, together with several of their O‐methylation products, as catalyzed by catechol‐O‐methyl transferase, were clearly identified after incubation of the liver slices with AOH and AME. These metabolites were predominantly present as conjugates with glucuronic acid and/or sulfate. In preliminary studies with bile duct‐cannulated male rats dosed with AOH by gavage, the four monohydroxylated metabolites of AOH could also be demonstrated in the bile either as catechols or as O‐methyl ethers. Conclusion: These experiments clearly show that AOH and AME undergo catechol formation in vivo and warrant closer examination of the toxicological significance of this metabolic pathway. 相似文献
107.
Pim van der Asdonk Hans C. Hendrikse Marcos Fernandez‐Castano Romera Dion Voerman Britta E. I. Ramakers Dennis W. P. M. Löwik Rint P. Sijbesma Paul H. J. Kouwer 《Advanced functional materials》2016,26(16):2609-2616
Controlling the organization of functional supramolecular materials at both short and long length scales as well as creating hierarchical patterns is essential for many biological and electrooptical applications. It remains however an extremely challenging objective to date, particularly in water‐based systems. In this work, it is demonstrated that water‐processable self‐assembling materials can be organized from micrometers to centimeters in any direction using liquid crystal templating in combination with photoaddressable command layers. The structural assemblies that are prepared are readily transformed into optically active π‐conjugated polymers after photopolymerization. After this step, the template may be removed to leave the functional material well‐organized on the substrate. The advantage of this approach is that it lacks specific molecular interactions and uses simple techniques such as spin coating and photoillumination and it may therefore be applied to a wide range of (aqueous) materials. 相似文献
108.
Altmann D Schaar H Bartel C Schorkopf DL Miller I Kreuzinger N Möstl E Grillitsch B 《Water research》2012,46(11):3693-3702
Tertiary wastewater treatment plant effluent before and after ozonation (0.6-1.1 g O3/g DOC) was tested for aquatic ecotoxicity in a battery of standardised microbioassays with green algae, daphnids, and zebrafish eggs. In addition, unconjugated estrogen and 17β-hydroxyandrogen immunoreactive substances were quantified by means of enzyme immunoassays, and endocrine effects were analysed in a 21-day fish screening assay with adult male and female medaka (Oryzias latipes). Ozonation decreased estrogen-immunoreactivity by 97.7 ± 1.2% and, to a lesser extent, androgen-immunoreactivity by 56.3 ± 16.5%. None of the short-term exposure ecotoxicity tests revealed any adverse effects of the tertiary effluent, neither before nor after the ozonation step. Similarly in the fish screening assay, reproductive fitness parameters showed no effects attributed to micropollutants, and no detrimental effects of the effluents were observed. Based on the presented screening, ozonation effectively reduced steroid hormone levels in the wastewater treatment plant effluent without increasing the effluent's ecotoxicity. 相似文献
109.
Biofuels: network analysis of the literature reveals key environmental and economic unknowns 总被引:1,自引:0,他引:1
Ridley CE Clark CM Leduc SD Bierwagen BG Lin BB Mehl A Tobias DA 《Environmental science & technology》2012,46(3):1309-1315
Despite rapid growth in biofuel production worldwide, it is uncertain whether decision-makers possess sufficient information to fully evaluate the impacts of the industry and avoid unintended consequences. Doing so requires rigorous peer-reviewed data and analyses across the entire range of direct and indirect effects. To assess the coverage of scientific research, we analyzed over 1600 peer-reviewed articles published between 2000 and 2009 that addressed 23 biofuels-related topics within four thematic areas: environment and human well-being, economics, technology, and geography. Greenhouse gases, fuel production, and feedstock production were well-represented in the literature, while trade, biodiversity, and human health were not. Gaps were especially striking across topics in the Southern Hemisphere, where the greatest potential socio-economic benefits, as well as environmental damages, may co-occur. There was strong asymmetry in the connectedness of research topics; greenhouse gases articles were twice as often connected to other topics as biodiversity articles. This could undermine the ability of scientific and economic analyses to adequately evaluate impacts and avoid significant unintended consequences. At the least, our review suggests caution in this developing industry and the need to pursue more interdisciplinary research to assess complex trade-offs and feedbacks inherent to an industry with wide-reaching potential impacts. 相似文献
110.
Susanne Kohl Britta Baumann Francesca Dassie Anja K. Mayer Maria Solaki Peggy Reuter Laura Kühlewein Bernd Wissinger Pietro Maffei 《International journal of molecular sciences》2021,22(15)
Achromatopsia (ACHM) is a rare autosomal recessively inherited retinal disease characterized by congenital photophobia, nystagmus, low visual acuity, and absence of color vision. ACHM is genetically heterogeneous and can be caused by biallelic mutations in the genes CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, or ATF6. We undertook molecular genetic analysis in a single female patient with a clinical diagnosis of ACHM and identified the homozygous variant c.778G>C;p.(D260H) in the CNGA3 gene. While segregation analysis in the father, as expected, identified the CNGA3 variant in a heterozygous state, it could not be displayed in the mother. Microsatellite marker analysis provided evidence that the homozygosity of the CNGA3 variant is due to partial or complete paternal uniparental isodisomy (UPD) of chromosome 2 in the patient. Apart from the ACHM phenotype, the patient was clinically unsuspicious and healthy. This is one of few examples proving UPD as the underlying mechanism for the clinical manifestation of a recessive mutation in a patient with inherited retinal disease. It also highlights the importance of segregation analysis in both parents of a given patient or especially in cases of homozygous recessive mutations, as UPD has significant implications for genetic counseling with a very low recurrence risk assessment in such families. 相似文献