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Models and observations of sunspot penumbrae

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1670-1677页

作者： BORRERO juan manuel Max Planck Institut fr Sonnensystemforschung Max Planck Strasse 2 D 37191 Katlenburg-Lindau Germany

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

关键词： sunspots magnetic fields spectropolarimetry magnetohydrodynamics

Acute kidney injury in severely injured patients admitted to the Intensive Care Unit

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Military Medical Research 2021年第2期8卷 141-147页

作者： Alberto F.García Ramiro Manzano-nunez juan G.Bayona Maria P.Naranjo Dary Neicce Villa manuel Moreno Sebastian Ossa juan M.Martinez Nathalia Martinez juan C.Puyana Division of Trauma and Acute Care Surgery Department of SurgeryFundación Valle del LiliCaliColombia Clinical Research Center Fundación Valle del LiliCaliColombia Escuela de Medicina Ciencias de la SaludUniversidad del RosarioCarrera 98#18-49760001BogotaColombia Méderi Hospital Universitario Mayor Colombia School of Medicine Universidad ICESI(ICESI University)CaliColombia Department of Surgery University of PittsburghPittsburghPAUSA

Background:Our objective was to identify possible associations between clinical and laboratory variables and the risk of developing acute kidney injury(AKI)in severely injured patients admitted to the Intensive Care Unit(ICU)for whom creatine kinase(CK)levels were ***:For this retrospective observational study,we analyzed adult trauma patients admitted to the ICU from 2011 to 2015 at Fundación Valle del Lili(FVL)University *** primary outcome was the incidence of *** regression analysis was used to assess risk factors for this ***:A total of 315 patients were *** trauma mechanisms were blunt(n=130),penetrating(n=66)and blast(n=44)*** median[interquartile range,(IQR)of injury severity score(ISS)was 21(16–29).AKI developed in 75 patients(23.8%).Multivariate regression analysis revealed that the thoracic abbreviated injury scale(AIS)value(median(IQR)in the AKI group:3(0–4)],Acute Physiology and Chronic Health Evaluation(APACHE Ⅱ)score[median(IQR)in the AKI group:18(10–27)],CK greater than 5000 U/L,lactic acid concentration at admission,and dobutamine administration were independently associated with ***:We found that age,APACHE Ⅱ score,thoracic trauma,lactic acidosis,and dobutamine administration were independently associated with *** surgeons need to be aware of the increased odds of AKI if one of these factors is identified during the evaluation and treatment of injured patients.

关键词： Rhabdomyolysis Wounds and injuries Acute kidney injury Critical care Trauma

Age and sex differences in niche use at molt and its effect on plumage coloration characteristics in a bird

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Current Zoology 2019年第3期65卷 251-260页

作者： Emilio PAGANI-nunez Craig R.A.BARNETT juan Carlos SENAR State Key Laboratory of Biocontrol Department of Ecology/School of Life Sciences Sun Yat-sen University Guangzhou China Department of Zoology Graduate School of Science University of Kyoto Kitashirakawaoiwake-cho Sakio-ku Kyoto Japan Natural History Museum of Barcelona Barcelona Spain

Bird plumage is often very colorful and can communicate the quality of the bearer to conspecifics. These plumage-based signals of quality are composed of multiple pigments (e.g., melanin and carote no ids). Therefore, sex and age classes, which often show marked differe nces in plumage coloration, may have different dietary needs for the different plumage components and this might promote pref ere nces for differe nt dietary niches at different molting stages. However, no study has addressed the role that changes in niche use play in the expression of multiple component plumage signals in birds. We used stable isotope analysis to test the hypothesis that niche use is related to age and sex and to differently cultured plumage patches, yellow carotenoid-based and black melanin-based, in great tits Parus major. We recorded high niche overlap between plumage patches, although δ15N was higher in black than yellow plumage. Niche overlap was relatively low for age classes and relatively high for sex classes, and age classes showed a contrasting pattern of niche overlap between carotenoid- and melanin-based plumages. Moreover,δ13C, but not δ15N, had a significant negative relationship with carotenoid-based plumage, which was only apparent in juveniles. Take n together, our results demonstrate that n iche use had a moderate in fluence on plumage coloration characteristics of great tit individuals, mostly associated with δ13C rather than with δ15N and with age rather than with sex. Therefore, our study is significant because it confirms the releva nee of n iche use duri ng orn ame nt production in free-livi ng birds.

关键词： carotenoids great tits melanin multiple ornaments niche overlap stable isotopes

Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-Díaz manuel Barragán-Villarejo juan Carlos Olives-Camps juan manuel Mauricio JoséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Hot corrosion mechanism of yttria-stabilized zirconia powder in the presence of molten Na_(2)SO_(4)+V_(2)O_(5) salts

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Rare Metals 2021年第5期40卷 1307-1316页

作者： Jhonattan De la Roche juan manuel Alvarado-Orozco Alejandro Toro Tribology and Surfaces Group Universidad Nacional de ColombiaMedellin 050041Colombia Centro de Ingeniena y Desarrollo Industrial-CIDESI Queretaro 76125Mexico Consorcio de Manufactura Aditiva-CONMAD Queretaro 76125Mexico

The hot corrosion behavior of yttria-stabilized zirconia(YSZ)powder specimens exposed to Na_(2)SO_(4)/V_(2)O_(5) salts mixtures at high temperature was *** tests were carried out at 1000℃ for 10 h,the salt concentrations varied from 0.1 wt%to 1.00 wt%,and the Na_(2)SO_(4)/V_(2)O_(5) mass ratios were between 0.20 and 0.44 following a factorial design 22.X-ray diffraction(XRD)analyses of the tested samples showed with a confidence of95%that the mixture composed of 32 wt%Na_(2)SO_(4)+68 wt%V_(2)O_(5),and 1.00 wt% salt concentration led to high destabilization of the t’-YSZ phase and formation of YVO_(4) products.A second set of experiments were conducted to assess the influence of temperature on the hot corrosion response of the YSZ in the range between 490 and 1100℃.Thermogravimetric analysis(TGA)experiments and Rietveld adjustments of XRD patterns showed that the mass loss of the samples varied with testing temperature and also that the major destabilization of tetragonal phase occurred at 900℃.

关键词： Hot corrosion Molten salts Yttria-stabilized zirconia Thermal barrier coatings

HEART RATE VARIABILITY DURING HIGH-INTENSITY EXERCISE

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Journal of Systems Science & Complexity 2013年第1期26卷 104-116页

作者： SARMIENTO Samuel GARCIA-MANSO juan manuel MARTIN-GONZALEZ juan manuel VA-AMONDE Diana CALDERóN Javier DA SILVA-GRIGOLETTO Marzo Edir Department of Physical Education University of Las Palmas de Gran Canaria Spain. Physics Department University of Las Palmas de Gran Canaria Spain. Department of Morphological Sciences School of Medicine University of Cdrdoba Spain. Physical Activity Sciences Faculty Polytechnic University of Madrid Spain. Andalusian Centre of Sports Medicine Cdrdoba Spain.

The aim of this paper is to describe and analyse the behaviour of heart rate variability(HRV)during constant-load,high-intensity exercise using a time frequency analysis(Wavelet Transform).Eleven elite cyclists took part in the study(age:18.6±3.0 years;VO_(2max):4.88±0.61 litres·min^(-1)).Initially,all subjects performed an incremental cycloergometer test to determine load power in a constant load-test(379.55±36.02 W;89.0%).HRV declined dramatically from the start of testing(p<0.05).The behaviour of power spectral density within the LF band mirrored that of total energy,recording a significant decrease from the outset LF peaks fell rapidly thereafter,remaining stable until the end of the ***-VHF fell sharply in the first 20 to 30 *** relative weighting(%) of HF-VHF was inverted with the onset of fatigue,[1.6%at the start,7.1(p<0.05) at the end of the first phase,and 43.1%(p<0.05) at the end of the test].HF-VHF_(peak) displayed three phases:a moderate initial increase,followed by a slight fall,thereafter increasing to the end of the *** LF/HF-VHF ratio increased at the start,later falling progressively until the end of the first phase and remaining around minimal values until the end of the test.

关键词： Cycling heart rate variability wavelet.

Rethinking de novo immune hepatitis,an old concept for liver allograft rejection:relevance of glutathione S-transferase T1 mismatch

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World Journal of Gastroenterology 2018年第29期24卷 3239-3249页

作者： Isabel Aguilera Elena Aguado-Dominguez Jose manuel Sousa Antonio nunez-Roldan Department of Immunology Instituto de Biomedicina de Sevilla(IBIS)Hospital Universitario Virgen del RocíoSevilla 41013Spain Digestive and Liver Diseases Service Hospital Universitario Virgen del RocíoSevilla 41013Spain

Antibody-mediated rejection(AMR) in liver transplantation has long been underestimated. The concept of the liver as an organ susceptible to AMR has emerged in recent years, not only in the context of the major histocompatibility complex with the presence of HLA donor-specific antibodies, but also with antigens regarded as "minor", whose role in AMR has been demonstrated. Among them, antibodies against glutathione S-transferase T1 have been found in 100% of patients with de novo autoimmune hepatitis(dn AIH) when studied. In its latest update, the Banff Working Group for liver allograft pathology proposed replacing the term dn AIH with plasma cell(PC)-rich rejection. Antibodies to glutathione S-transferase T1(GSTT1) in null recipients of GSTT1 positive donors have been included as a contributory but nonessential feature of the diagnosis of PC-rich rejection. Also in this update, non-organ-specific anti-nuclear or smooth muscle autoantibodies are no longer included as diagnostic criteria. Although initially found in a proportion of patients with PC-rich rejection, the presence of autoantibodies is misleading since they are not diseasespecific and appear in many different contexts as bystanders. The cellular types and proportions of the inflammatory infiltrates in diagnostic biopsies have been studied in detail very recently. PC-rich rejection biopsies present a characteristic cellular profile with a predominance of T lymphocytes and a high proportion of PCs, close to 30%, of which 16.48% are Ig G4+. New data on the relevance of GSTT1-specific T lymphocytes to PC-rich rejection will be discussed in this review.

关键词： glutathione S-transferase T1 mismatch liver allograft rejection plasma cell-rich rejection de novo autoimmune hepatitis donor-specific antibodies newCAST cell quantification IgG4+plasma cell T lymphocytes

BASKETBALL SCORING IN NBA GAMES:AN EXAMPLE OF COMPLEXITY

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Journal of Systems Science & Complexity 2013年第1期26卷 94-103页

作者： DE SA GUERRA Yves MARTíN GONZALEZ juan manuel SARMIENTO MONTESDEOCA Samuel RODRIGUEZ RUIZ David ARJONILLA LóPEZ Nieves GARCíA-MANSO juan manuel Departament of Phisical Education University of Las Palmas de Gran Canaria Departament of Physics University of Las Palmas de Gran Canaria

Scoring in a basketball game is a highly dynamic, non-linear process. NBA teams try to be more and more competitive each season. For instance, they incorporate into their rosters the best players in the world. This and other mechanisms concur to make the scoring process in NBA games exciting and rarely predictable. This paper is to study the behavior of timing and scoring in basketball gaines. The authors analyze all the games in five NBA regular seasons （2005-06, 2006-07, 2007-08, 2008-09, 2009-10）, for a total of 6150 games. Scoring does not behave uniformly; therefore, the authors also analyze the distributions of the differences in points in the basketball games. To further analyze the behavior of the tail of the distribution, the authors also carry out a semilog-plot and a log-log plot to verify whether this trend approaches a Poisson distribution or a PL. This paper reveals different areas of behavior related to the score, with specific instances of time that could be considered tipping points of the game. The presence of these critical points suggests that there are phase transitions where the dynamic scoring of the games varies significantly.

关键词： Complexity NBA non-linear Poisson power law.

Hepatopulmonary syndrome: What we know and what we would like to know

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World Journal of Gastroenterology 2016年第25期22卷 5728-5741页

作者： Israel Grilo-Bensusan juan manuel Pascasio-Acevedo Digestive Diseases Department HAR écija APS Bajo Guadalquivir Unit for the Clinical Management of Digestive Diseases IBIS CIBERehd Virgen del Rocío University Hospital

Hepatopulmonary syndrome (HPS) is characterized by abnormalities in blood oxygenation caused by the presence of intrapulmonary vascular dilations (IPVD) in the context of liver disease, generally at a cirrhotic stage. Knowledge about the subject is still only partial. The majority of the information about the etiopathogenesis of HPS has been obtained through experiments on animals. Reported prevalence in patients who are candidates for a liver transplantation (LT) varies between 4% and 32%, with a predominance of mild or moderate cases. Although it is generally asymptomatic it does have an impact on their quality of life and survival. The diagnosis requires taking an arterial blood gas sample of a seated patient with alveolar-arterial oxygen gradient (AaO2) ≥ 15 mm Hg, or ≥ 20 mm Hg in those over 64 years of age. The IPVD are identified through a transthoracic contrast echocardiography or a macroaggregated albumin lung perfusion scan (99mTc-MAA). There is currently no effective medical treatment. LT has been shown to reverse the syndrome and improve survival rates, even in severe cases. Therefore the policy of prioritizing LT would appear to increase survival rates. This paper takes a critical and clinical look at the current understanding of HPS, as well as the controversies surrounding it and possible future research.

关键词： Hepatopulmonary syndrome Liver cirrhosis Liver transplantation Contrast echocardiography Macroaggregated albumin lung perfusion scan