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Cropping Pattern Modifications Change Water Resource demands in the Beijing Metropolitan Area

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Journal of Integrative Agriculture 2012年第11期11卷 1914-1923页

作者： HUANG Jing bradley G Ridoutt XU Chang-chun ZHANGHai-lin CHEN Fu College of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China Commonwealth Scientific and Industrial Research Organisation (CSIRO) Sustainable Agriculture Flagship Victoria 3169 Australia

Adequate freshwater supply has become an issue of increasing local and international concern. Reducing water use in agriculture, which is the largest water using sector of the economy, is both important and urgent. The aim of this paper was to quantify how recent cropping pattern changes have influenced water resources in the great Beijing metropolitan area, an expanding megacity which also includes rural counties. Crop production affects blue water use through water consumption and water pollution, the latter assessed here using a critical dilution method. From 1990 to 2010, the total blue water used by crop production declined due to a decrease in overall cropped area, initially in response to local government policies favouring urban development. However, the average blue water use per hectare increased from 2 112 m3 ha-~ yr-~ in 1990 to 2 764 m3 ha-1 yr-1 in 2003, largely as the result of a transition from cereal to vegetable crops, and in particular an increase in intensively managed plastic and glass covered vegetable production systems. Current policies aim to conserve agricultural land, in the interests of food security, and to stimulate cereal production systems with higher ecosystem services provision. As such, in 2010 the average blue water use was 2 425 m3 ha-~ yr-l. These results demonstrate that cropping pattern changes in peri-urban regions and rural communities surrounding the Beijing metropolitan area can have a substantial impact on water resources. They also highlight the tradeoffs between food production and urban and industrial water supply and the need for integrated policy development.

关键词： blue water use water consumption water pollution cropping pattern adjustment peri-urban food production

What would a US green hydrogen energy economy look like?

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Clean Energy 2023年第5期7卷 1148-1172页

作者： thomas Tonon Independent researcher Ph.D.Aerospace and Mechanical SciencesPrinceton University1971.11 Bolfmar AvenuePrinceton JunctionNJ 08550USA

detailed description is given for a hypothetical US hydrogen economy with solar and wind energy supplying virtually all current energy needs and with electrolytic hydrogen the energy carrier and storage *** fuels provide nonfuel products(plastics,chemicals,cement and asphalt).Only current technologies are considered and hydrogen storage accommodates generation intermit-tency and variability,using pit storage of high-pressure vessels in open air,yielding daily storage round-trip energy installation costs of 722 and 538$/kWh for electric and thermal,respectively;and for power,2351 and 2240$/kW for electric and thermal,*** long-duration storage,the costs are 94.1 and 23.8$/kWh and 937 and 845$/kW,*** energy generation 20%over baseline accommodates low-season generation,obviates much required storage and ensures that reserves are topped off;96%of US 2022 total energy consumption is provided *** the default scenario(demand energy portions:half photovoltaic,quarter on-shore wind and quarter offshore wind),the surface area for the farms(including offshore surface)requires~4.6%of the US 48-state land *** 350 pit storage sites provide both daily and long-duration storage,with the latter accounting for complete loss of generation for 4 days over a quarter of the *** pipelines and a renewed electric grid transmit and distribute *** installation cost of the public infrastructure is~$27.8 trillion for the default *** scenarios show significant in-frastructure and cost savings when batteries are used for transportation and/or utility storage,provided current insufficiencies can be ***,cost levels in money,surface and infrastructure are within existing levels already achieved in historical events and modern living.

关键词： hydrogen economy renewable energy hydrogen storage hydrogen pipelines sustainable net zero

Recent result from the A2 real photon facility at MAMI

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Chinese Physics C 2009年第12期33卷 1120-1126页

作者： Andreas thomas Institut fr Kernphysik University Mainz J.-J. Becherweg 45 D-55099 Mainz Germany

The upgraded MAMI C accelerator is delivering electrons with an energy of 1558 MeV routinely. The A2 collaboration is doing experiments with energy marked polarised real photons produced via ＂Bremsstrahlung＂. Recent results from the GdH-experiment using a longitudinal polarised frozen spin target in combination with the dAPHNE detector and from the Crystal Ball experiment at MAMI are presented.

关键词： photonuclear reactions polarization phenomena in reactions polarized and other targets leptoninduced reactions

A new institution devoted to insect science： The Florida Museum of Natural History, McGuire Center for Lepidoptera and Biodiversity

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Insect Science 2012年第3期19卷 426-428页

作者： Akito Y. Kawahara thomas C. Emmel Jacqueline Miller Andrew d. Warren McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural History University of Florida Gainesville Florida USA

The Florida Museum of Natural History＇s McGuire Center for Lepidoptera and Biodiversity, on the University of Florida campus in Gainesville, Florida, has become one of the world＇s largest institutions for research on butterflies and moths, and an important research facility for insect science. The facility was constructed by combining the staff and merging the Lepidoptera holdings from the Allyn Museum of Entomology, the Florida State Collection of Arthropods and other University of Florida collections, and now includes over ten million specimens from all over the world, rivaling some of the largest Lepidoptera research collections globally. The facility includes a team of domestic and international researchers studying many areas of lepidopterology, including behavior, biodiversity, biogeography, ecology, genomics, physiology, systematics and taxonomy. In this paper, we introduce the McGuire Center, its staff, and the many research activities for researchers across entomological disciplines.

关键词： Florida Museum of Natural History Lepidoptera lepidopterology McGuireCenter moth new research facility

Is thirty-seven years sufficient for full return of the ant biota following restoration?

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Ecological Processes 2013年第1期2卷 183-194页

作者： Jonathan d Majer Brian Heterick thomas Gohr Elliot Hughes Lewis Mounsher Andrew Grigg Curtin Institute for Biodiversity and Climate Curtin UniversityPO Box U1987PerthWA 6845Australia Alcoa of Australia Ltd PO Box 172PinjarraWA 6208Australia

Introduction:An assessment of whether rehabilitated mine sites have resulted in natural or novel ecosystems requires monitoring over considerable periods of time or the use of space-for-time substitution(chronosequence)***:To provide an assessment of ecosystem recovery in areas mined for bauxite in 1975,the ant fauna of one area planted with Eucalyptus resinifera,one seeded with mixed native species,one topsoiled but unrestored,and a forest reference was subjected to a‘long-term’study by sampling monthly and latterly annually between 1976 and 1989 using pitfall *** plots were resampled in 2012.A companion‘short-term’chronosequence study was performed in 1979 in 28 bauxite mines of various ages and restored by a range of different methods,plus three forest *** order to examine the assertion that the observed differences between restored areas and forest references will lessen with time,sampling using comparable methods was repeated in 2012 in seven of the original plots,representing progressive advances in rehabilitation technology:planted pines;planted eastern states eucalypts;planted native eucalypts;planted eucalypts over seeded understorey;and planted eucalypts on fresh,double-stripped topsoil,plus two forest reference ***:Ant and other invertebrate richness in the long-term study was initially superior in the seeded plot,with little difference between the planted and unplanted *** was concluded that although composition of the ant fauna had converged on that of the forest over the 14-year period,differences still *** 2012 resampling revealed that ant species richness and composition had deteriorated in the seeded plot,while values in the unplanted plot,which now supported naturally colonised trees and an understorey,had *** between all rehabilitated plots and forest still *** with the long-term study,the rate of fauna return and the type of ants present in the short-term study p

关键词： Bauxite mining Ant bioindicator Long-term study Chronosequence Seeding Planting Succession

Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： Jeffrey L Vallet Anthony K Mc Neel Jeremy R Miles bradley A Freking U.S. department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

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World Journal of Gastroenterology 2020年第22期26卷 2931-2947页

作者： Tea L Laursen thomas d Sandahl Konstantin Kazankov Jacob George Henning Gronbæk department of Hepatology and Gastroenterology Aarhus University HospitalAarhus N DK-8200Denmark Storr Liver Centre Westmead Institute for Medical ResearchWestmead HospitalSydney NSW 2145Australia University of Sydney Sydney NSW 2145Australia

More than five years ago,the treatment of hepatitis C virus infection was revolutionized with the introduction of all-oral direct-acting antiviral(dAA)*** proved highly efficient in curing patients with chronic hepatitis C(CHC),including patients with *** new dAA treatments were alleged to induce significant improvements in clinical outcome and prognosis,but the exact cause of the expected benefit was ***,little was known about how the underlying liver disease would be affected during and after viral *** this review,we describe and discuss the liver-related effects of the new treatments in regards to both pathophysiological aspects,such as macrophage activation,and the time-dependent effects of therapy,with specific emphasis on inflammation,structural liver changes,and liver function,as these factors are all related to morbidity and mortality in CHC *** seems clear that antiviral therapy,especially the achievement of a sustained virologic response has several beneficial effects on liver-related parameters in CHC patients with advanced liver fibrosis or *** seems to be a timedependent effect of dAA therapy with viral clearance and the resolution of liver inflammation followed by more discrete changes in structural liver *** improvements lead to favorable effects on liver function,followed by an improvement in cognitive dysfunction and portal ***,the data provide knowledge on the several beneficial effects of dAA therapy on liverrelated parameters in CHC patients suggesting short-and long-term improvements in the underlying disease with the promise of an improved longterm prognosis.

关键词： Chronic hepatitis C Antiviral treatment Inflammation Liver fibrosis Liver cirrhosis Metabolic liver function Galactose elimination capacity Urea synthesis capacity Portal hypertension Hepatic encephalopathy

Targeting the m6A mRNA demethylase FTO suppresses vascular endothelial growth factor release and choroidal neovascularization

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Signal Transduction and Targeted Therapy 2023年第3期8卷 905-907页

作者： Shao-bin Wang Yosuke Nagasaka dionne Argyle Ayami Nagasaka Praveen Yerramothu bradley dGelfand Jayakrishna Ambati Center for Advanced Vision Science University of Virginia School of MedicineCharlottesvilleVAUSA department of Ophthalmology University of Virginia School of MedicineCharlottesvilleVAUSA department of Biomedical Engineering University of Virginia School of MedicineCharlottesvilleVAUSA department of Pathology University of Virginia School of MedicineCharlottesvilleVAUSA department of Microbiology Immunologyand Cancer BiologyUniversity of Virginia School of MedicineCharlottesvilleVAUSA

dear Editor,Vascular endothelial growth factor-A(VEGFA,also known as VEGF)is a critical angiogenic factor that regulates the physiological and pathological blood vessel growth.1 Increased abundance of VEGF in the eye underlies many forms of aberrant ocular angiogenesis and resultant vision loss,including in neovascular age-related macular degeneration(nvAMd),proliferative diabetic retinopathy(PdR).

关键词： degeneration ocular release

Bowel endometriosis: Colorectal surgeon's perspective in a multidisciplinary surgical team

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World Journal of Gastroenterology 2014年第42期20卷 15616-15623页

作者： Albert M Wolthuis Christel Meuleman Carla Tomassetti thomas d'Hooghe Anthony de Buck van Overstraeten André d'Hoore department of Abdominal Surgery University Hospital Leuven Leuven University Fertility Centre department of Obstetrics and Gynecology University Hospital Leuven

Endometriosis is a gynecological condition that presents as endometrial-like tissue outside the uterus and induces a chronic inflammatory reaction. Up to 15% of women in their reproductive period are affected by this condition. deep endometriosis is defined as endometriosis located more than 5 mm beneath the peritoneal surface. This type of endometriosis is mostly found on the uterosacral ligaments, inside the rectovaginal septum or vagina, in the rectosigmoid area, ovarian fossa, pelvic peritoneum, ureters, and bladder, causing a distortion of the pelvic anatomy. The frequency of bowel endometriosis is unknown, but in cases of bowel infiltration, about 90% are localized on the sigmoid colon or the rectum. Colorectal involvement results in alterations of bowel habits such as constipation, diarrhea, tenesmus, dyschezia, and, rarely, rectal *** diagnosis must be made in case of irritable bowel syndrome,solitary rectal ulcer syndrome,and a rectal tumor.A precise diagnosis about the presence,location,and extent of endometriosis is necessary to plan surgical *** laparoscopic treatment has become the standard of *** on the size of the lesion and site of involvement,fullthickness disc excision or bowel resection needs to be performed by an experienced colorectal *** outcomes,following bowel resection for severe endometriosis,regarding pain and recurrence rate are good with a pregnancy rate of 50%.

关键词： Endometriosis Colorectal endometriosis deeply infiltrative endometriosis Laparoscopy diagno-sis Treatment