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Journal of Modern Physics 2013年第11期4卷 1546-1553页

作者： Werner schmidt Fachbereich Biologie Philipps-Universitat MarburgMarburgGermany Fachbereich Biologie Universitat KonstanzKonstanzGermany

Various spectroscopic experiments performed on the AIRBUS ZERO g—located in Bordeaux, France—in the years 2002 to 2012 exhibit minute optical reflection/absorption changes (gIACs) as a result of gravitational changes between 0 and 1.8 g in various biological species such as maize, oats, Arabidopsis and particularly Phycomyces sporangiophores. During a flight day, the AIRBUS ZERO g conducts 31 parabolas, each of which lasts about three minutes including a period of 22 s of weightlessness. So far, we participated in 11 parabolic flight campaigns including more than 1000 parabolas performing various kinds of experiments. During our campaigns, we observed an unexplainable variability of the measuring signals (gIACs). Using gPS-positioning systems and three dimensional magnetic field sensors, these finally were traced back to the changing earth’s magnetic field associated with the various flight directions. This is the first time that the interaction of gravity and the Earth’ magnetic field in the primary induction process in living system has been observed.

关键词： MDWS(Micro Dual Wavelength Spectrometer) gIAC(gravity Induced Absorption Change) AIRBUS-300-ZERO-g Parabolic Flight Micro-and Hypergravity Three Dimensional Earth’s Magnetic Field global Positioning System(gPS) google Earth

gravireception in <i>Phycomyces</i>: Threshold Determination on the Sounding Rocket TEXUS 50

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Journal of Modern Physics 2015年第10期6卷 1381-1389页

作者： Werner schmidt Fachbereich Biologie Philipps-Universit&#228 t Marburg Marburg Germany Fachbereich Biologie Universit&#228 t Konstanz Konstanz Germany

Under parabolic flight conditions microgravity is not lower than 3 to 5 times 10-2 g. In contrast to parabolic flights, sounding rocket flights are virtually vibrational-free allowing microgravity as low as 10-5 g. Thus, a rotating platform serving as centrifuge allows the precise generation of gravitational forces ranging from 5 to 100 mg (not possible during parabolic flights). On this basis we determined the threshold1 for optical reflection/absorption changes in Phycomyces to be lower than 25 × 10-3 g. This compares well with the threshold determination of gravitropism in Phycomyces on a clinostat centrifuge. Kinetics of gravity-induced absorption changes and gravity as generated by the on-board centrifuge do not coincide but show a distinctive hysteresis with a latency of 4 s (75 mg-ramp, pull-up).

关键词： MDWS (Micro-Dual Wavelength Spectrophotometer) Δ gIAC (Differential gravity-Induced Absorption Change) Phycomyces blakesleeanus Sporangiophore Micro- and Hypergravity Texus 50 Sounding Rocket gravireception

Conditions Supporting Funnel Cloud Development in Alaska

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Atmospheric and Climate Sciences 2017年第2期7卷 223-245页

作者： Stanley g.Edwin Nicole Molders Katja Friedrich Sebastian schmidt Richard Thoman Department of Atmospheric Sciences College of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksAKUSA geophysical Institute University of Alaska FairbanksFairbanksAKUSA Department of Atmospheric and Oceanic Sciences University of Colorado at BoulderBoulderCOUSA National Weather Service Forecast Office NOAAFairbanksAKUSA

The characteristics and climatology of funnel clouds in Alaska were examined using operational radiosondes, surface meteorological observations, and reanalysis data. Funnel clouds occurred under weak synoptic forcing between May and September between 11 am and 6 pm Alaska Daylight Time with a maximum occurrence in July. They occurred under Convective Available Potential Energy >500 J·kg-1 and strong low-level wind shear. Characteristic atmospheric profiles during funnel cloud events served to develop a retrieval algorithm based on similarity testing. Out of more than 129,000 soundings between 1971 and 2014, 2724, 442, and 744 profiles were similar to the profiles of observed funnel cloud events in the Interior, Alaska West Coast, and Anchorage regions. While the number of reported funnel clouds has increased since 2000, the frequency of synoptic situations favorable for such events has decreased.

关键词： Alaska Funnel Clouds Funnel Cloud Climatology Similarity Retrieval Algorithm Mesoscale Forcing for Funnel Cloud Formation in Alaska

Source apportionment of atmospheric particulate carbon in Las Vegas,Nevada,USA

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Particuology 2013年第1期11卷 110-118页

作者： Mark C.green Judith C.Chow M.-C.oliver Chang L.-W.Antony Chen Hampden D.Kuhns Vicken R.Etyemezian John g.Watson Division of Atmospheric Sciences Desert Research Institute2215 Raggio ParkwayRenoNV 89512USA Division of Atmospheric Sciences Desert Research Institute.2215 Raggio ParkwayRenoNV 89512USA State Key Laboratory of Loess and Quaternary geology Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina California Air Resources Board 9528 Telstar Ave.El MonteCA 91731USA

A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United States. Twenty-four hour average ambient samples were collected for mass, ions, elements, organic carbon （OC）, elemental carbon （EC）, and trace organic markers analysis. Additional measurements were made to determine diurnal patterns in light-absorbing black carbon （BC） as a marker for combustion sources. Carbonaceous PM sources of on-road gasoline vehicles, on-road diesel vehicles, and off-road diesel engines were characterized with their chemical profiles, as well as fuel-based emission factors, using an In-Plume Sampling System. The Effective Variance Chemical Mass Balance （EV-CMB） source apportionment model was applied to the ambient samples collected, using source profiles developed in this study as well as profiles from other relevant studies. Four main sources contributed to PM2.5 carbon within the Las Vegas Valley：（1） paved road dust, （2） on-road gasoline vehicles, （3） residential wood combustion, and （4） on-road diesel vehicles. CMB estimated that on-road mixed fleet gasoline vehicles are the largest source for OC and EC at all the sites. The contribution of paved road dust to both OC and EC was 5-10% at the four sites. On-road diesel vehicles contribute 22% of the OC and 34% of the EC at a site near the city center, which is located immediately downwind of a major freeway. Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites, These results are consistent with our conceptual model, and the research methodology may be applied to studying other urban areas.

关键词： Source characterization Mobile sources Elemental carbon Source apportionment Organic marker

Taxonomic status of grey-headed Yellow Wagtails breeding in western China

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Avian Research 2021年第4期12卷 534-543页

作者： Alexander Hellquist Fredrik Friberg Petter Haldén Peter schmidt Ming Ma gou Jun Urban Olsson Per Alström Fatburs kvarngata 17 11864 StockholmSweden Xinjiang Institute of Ecology and geography Chinese Academy of SciencesNo.818 Beijing RoadUrumqi 830011XinjiangChina Xinjiang Birdwatching Society 311 Nongda East RoadUrumqi 830091XinjiangChina Systematics and Bio-diversity Department of Biology and Environmental SciencesUniversity of GothenburgGöteborgSweden gothenburg global Biodiversity Centre GothenburgSweden Animal Ecology Department of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityNorbyvägen 18D75236 UppsalaSweden Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Edeby 9 74191 KnivstaSweden Lenabergsvägen 33 74392 VattholmaSweden Tallmovägen 9 75645 UppsalaSweden

Background:Field studies from 2011 onwards have demonstrated the presence of a breeding population of Yellow Wagtails(Motacilla flava)in the Xinjiang Uygur Autonomous Region,China that is phenotypically distinct from known subspecies occurring in *** we describe the plumages and vocalisations of this population and discuss its taxonomic ***:The analysis of plumage is based on field studies and photos available *** of vocalisations are compared with recordings from other Yellow Wagtail populations,and differences are analysed based on *** DNA from one individual is compared to other Yellow Wagtail ***:Unlike *** subspecies breeding in or near Xinjiang,males in the studied population show a blue-grey head without prominent white supercilium,being most similar to the widely disjunct *** differ from the similarly widely allopatric ***,which might occur as a migrant or vagrant in Xinjiang,by on average cleaner yellow breast and more extensive white on the throat,and from the widely disjunct *** and ***,which might also occur on migration in that area,by softer contact calls and slower pace of *** are similar to female *** in *** mitochondrial ND2 tree shows the single sample from Xinjiang to be nested in the clade of western Yellow Wagtail ***:We discuss whether the Xinjiang breeding population could represent an intergrade between subspecies breeding nearby,or whether it is better regarded as a separate as yet unrecognized *** argue that the localization of its apparent range in relation to other subspecies along with fairly consistent male and female plumages suggest that it is more likely to represent an undescribed taxon,but conclude that more research is needed to firmly establish its status.

关键词： Bioacoustics Mitochondrial DNA Morphology Motacilla flava Systematics Undescribed populations

Pediatric radiological diagnostic procedures in cases of suspected child abuse

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Health 2010年第3期2卷 237-245页

作者： C. Erfurt g. Hahn D. Roesner U. schmidt Pediatric Radiology Department University Hospital “Carl Gustav Carus” Dresden Germany Technical University Dresden Dresden Germany University Hospital “Carl gustav Carus” Dresden Germany

Advanced and specialized radiological diagnostic procedures are essential in cases of clinically diagnosed injuries to the head, thorax, abdomen or extremities of a child, especially if there is no case history or if the reporting of an inadequate trauma suggests battered child syndrome. In particular, these diagnostic procedures should aim at detecting lesions of the central nervous system (CNS), so that the treatment can be immediately initiated. If the diagnostic imaging reveals findings typically associated with child abuse, accurate documentation constituting evidence, which will stand up in court, is required to prevent any further endangerment of the child’s welfare.

关键词： Child Abuse Battered Child Syndrome Shaken Baby Syndrome Non-Accidental Injury Pediatric Radiological Diagnostics

夏季自然水体与大气界面间气态总汞的交换通量

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中国科学（D辑） 2002年第7期32卷 609-616页

作者：冯新斌 S.Jonas g.Katarina L.oliver 中国科学院地球化学研究所 Department

利用动力学通量箱法与高时间分辨率大气测汞仪的联用技术,在瑞典西南的Kristineberg海洋观测站（KMRS）和Knobesholm的Hovg(?)rds(?)n河分别测定了夏季海水和河水表面与大气间汞的交换通量.在夏季,河水和海水都是大气汞的源.河水和海水... 详细信息

利用动力学通量箱法与高时间分辨率大气测汞仪的联用技术,在瑞典西南的Kristineberg海洋观测站（KMRS）和Knobesholm的Hovg(?)rds(?)n河分别测定了夏季海水和河水表面与大气间汞的交换通量.在夏季,河水和海水都是大气汞的源.河水和海水表面与大气间汞的交换通量在夏季具有一致的昼夜变化规律,白天由水体向大气排汞且在正午达到最大值;夜间排汞量相对较小且有时会出现大气汞向水体沉降.河水与大气间汞的交换通量与光照强度呈线性正相关关系,与大气相对湿度呈线性负相关性,同时还与水体温度存在指数相关性.海水与大气间汞交换通量只与光照强度存在良好的线性正相关关系.水体中溶解态气汞的过饱和是水体汞向大气释放的驱动力.

关键词：夏季自然水体大气界面溶解态气汞生物地球化学循环交换通量海水河水水体污染

Dietary copper triggers onset of fulminant hepatitis in the Long-Evans cinnamon rat model

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World Journal of gastroenterology 2012年第39期18卷 5542-5550页

作者： Ramsi Siaj Vanessa Sauer Sandra Stppeler Hans-Ullrich Spiegel gabriele Khler Andree Zibert Hartmut HJ schmidt Klinik und Poliklinik für Transplantationsmedizin Universittsklinikum MünsterD-48149 MünsterGermany Abteilung Chirurgische Forschung Klinik und Poliklinik für Allgemein-und ViszeralchirurgieUniversittsklinikum MünsterD-48149 MünsterGermany gerhard-Domagk-Institut für Pathologie Universittsklinikum MünsterD-48149 MünsterGermany

AIM： To investigate the impact of dietary copper given at different time points on the onset of fulminant hepatitis. METHODS： The Long-Evans cinnamon （LEC） rat mod- el of Wilson＇s disease （WD） was used to study the im- pact of high dietary copper （hCu） on the induction of fulminant hepatitis at early or late time points of life. High Cu diet was started in rat pups or in adults （month 5） for three months. Animals that received reduced di- etary copper （rCu） throughout their lifetime served as a control. Hepatitis-associated serum markers （alanine aminotransferase, aspartate transaminase, bilirubin） were analyzed in animal groups receiving hCu or rCu. Liver copper content and liver histology were revealed at sacrifice. A set of 5 marker genes previously found to be affected in injured liver and which are related to angiogenesis （Vegfa）, fat metabolism （Srebf1）, ex- tracellular matrix （Timp1）, oxidative stress （Hmox1）, and the cell cycle （Cdknla） were analyzed by real-time polymerase chain reaction. RESULTS： Regardless of the time point when hCu was started, LEC rats （35/36） developed fulminant hepati- tis and died. Animals receiving rCu （36/36） remained healthy, did not develop hepatitis, and survived long term without symptoms of overt disease, although liver copper accumulated in adult animals （477 ± 75 μg/g）. With regard to start of hCu, onset of fulminant hepatitis was significantly （P 〈 0.001） earlier in adults （35±9 d） that showed pre-accumulation of liver copper as com- pared to the pup group （77±15 d）. Hepatitis-associ- ated serum markers, liver copper and liver histology, as well as gene expression, were affected in LEC rats re- ceiving hCu. However, except for early and rapid onset of hepatitis, biochemical and molecular markers were similar at the early and late time points of disease. CONCLUSION： Rapid onset of fulminant hepatitis in asymptomatic LEC rats with elevated liver copper sug- gests that there is a critical threshold of liver copper which is imp

关键词： Wilson's disease Fulminant hepatitis Acuteliver failure Dietary copper Long-Evans cinnamon rat A TP7B

Influence of gastric inhibitory polypeptide on pentagastrinstimulated gastric acid secretion in patients with type 2 diabetes and healthy controls

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World Journal of gastroenterology 2006年第12期12卷 1874-1880页

作者： Juris J Meier Michael A Nauck Bartholomaeus Kask Jens J Hoist Carolyn F Deacon Wolfgang E schmidt Baptist gallwitz Department of Medicine I St. Josef-HospitalRuhr-University Bochum Germany Diabeteszentrum Bad Lauterberg Germany Department of Medical Physiology The Panum Institute University of Copenhagen Denmark Department of Medicine IV Eberhard-Karls- University Ttibingen Germany

AIM： gastric inhibitory polypeptide is secreted from intestinal K-cells in response to nutrient ingestion and acts as an incretin hormone in human physiology. While animal experiments suggested a role for gIP as an inhibitor of gastric secretion, the gIP effects on gastric acid output in humans are still controversial. METHODS： Pentagastrin was administered at an infusion rate of 1 μg . kg^-1 . h^-1 over 300 min in 8 patients with type 2 diabetes （2 female, 6 male, 54± 10 years, BMI 30.5 ± 2.2 kg/m^2; no history of autonomic neuropathy） and 8 healthy subjects （2/6, 46 ± 6 years., 28.9 ± 5.3 kg/ m^2）. A hyperglycaemic clamp （140 mg/dl） was performed over 240 min. Placebo, gIP at a physiological dose （1 pmol . kg^-1 . min^-1）, and gIP at a pharmacological dose （4 mol . kg^-1 . min^-1） were administered over 60 min each. Boluses of placebo, 20 pmol gIP/kg, and 80 pmol gIP/kg were injected intravenously at the beginning of each infusion period, respectively. gastric volume, acid and chloride output were analysed in 15-min intervals. Capillary and venous blood samples were drawn for the determination of glucose and total gIP. Statistics were carried out by repeated-measures ANOVA and one-way ANOVA. RESULTS： Plasma glucose concentrations during the hyperglycaemic clamp experiments were not different between patients with type 2 diabetes and controls. Steady-state gIP plasma levels were 61 ±8 and 79 ± 12 pmol/I during the low-dose and 327±35 and 327± 17 pmol/I during the high-dose infusion of gIP, in healthy control subjects and in patients with type 2 diabetes, respectively （P= 0.23 and p 0.99）. Pentagastrin markedly increased gastric acid and chloride secretion （P〈 0.001）. There were no significant differences in the rates of gastric acid or chloride output between the experimental periods with placebo or any dose of gIP. The temporal patterns of gastric acid and chloride secretion were similar in patients with type 2 diabetes and healthy controls （P= 0.86 and P= 0.6

关键词： gastric inhibitory polypeptide gastric acid secretion Type 2 diabetes Hyperglycemic clamp Pentagastrin-stimulated acid secretion

Sporadic versus hereditary gastrinomas of the duodenum and pancreas: Distinct clinico-pathological and epidemiological features

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World Journal of gastroenterology 2006年第34期12卷 5440-5446页

作者： Martin Anlauf Nele garbrecht Tobias Henopp Anja Schmitt Regina Schlenger Andreas Raffel Markus Krausch oliver gimm Claus F Eisenberger Wolfram T Knoefel Henning Dralle Paul Komminoth Philipp U Heitz Aurel Perren günter Klppel Department of Pathology Universityof Kiel Germany Department of Pathology University of Zürich Switzerland Department of Pathology Universityof Kiel Germany Department of Forensic Medicine Universityof Kiel Germany Department of general Visceral andPediatric Surgery University of Düsseldorf Germany Department of general andVisceral Surgery University of Halle-Wittenberg Germany

gastrinomas are defined as gastrin secreting tumors that are associated with Zollinger-Ellison syndrome （ZES）. ZES is characterized by elevated fasting gastrin serum levels, positive secretin stimulation test and clinical symptoms such as recurrent peptic ulcer disease, gastroesophageal reflux disease and occasional diarrhea. genetically, nonhereditary （sporadic） gastrinomas are distinguished from hereditary gastrinomas, which are associated with multiple endocrine neoplasia type 1 （MEN1） syndrome. In general, duodenal gastrinomas are small and solitary if they are sporadic and multiple as well as hereditary. The sporadic gastrinomas occur in the duodenum or in the pancreas while the hereditary gastrinomas almost all occur in the duodenum. Our series of 77 sporadic duodenal neuroendocrine tumors （NETs） includes 18 patients （23.4%） with gastrinomas and ZES. Of 535 sporadic NETs in the pancreas collected from the NET archives of the departments of pathology in Zürich, Switzerland, and Kiel, germany, 24 patients （4.5%） suffered from sporadic pancreatic gastrinomas and ZES. These NETs have to be distinguished from tumors with immunohistochemical positivity for gastrin but without evidence of ZES. An additional 19 patients suffered from MEN1 and ZES. These patients showed exclusively duodenal gastrinomas, but not pancreatic gastrinomas. The prognosis of sporadic and MEN1- associated duodenal gastrinomas is better than that of pancreatic gastrinomas, since they progress slowly to liver metastasis. In summary, sporadic and MEN1- associated gastrinomas in the duodenum and pancreas show different clinico-pathological and genetic features. The incidence of sporadic duodenal gastrin-producing tumors is increasing, possibly due to optimized diagnostic procedures. In contrast, pancreatic MEN1- associated gastrinomas seem to be extremely rare. A considerable subset of tumors with immunohistochemical expression of gastrin but without evidence of ZES should be designated as functio

关键词： Endocrine tumor gastrinoma Multiple endocrine neoplasia type 1 Precursor lesion Zollinger-Ellison syndrome