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Increased Filamentous Growth of Candida albicans in Simulated Microgravity

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Genomics, Proteomics & Bioinformatics 2008年第1期6卷 42-50页

作者： Sara d. Altenburg Sheila M. Nielsen-Preiss Linda E. Hyman division of Health Sciences and department of Cell Biology and Neuroscience Montana State UniversityBozeman MT 59717 USA

Knowledge of simulated microgravity （SMG）-induced changes in the pathogenicity of microorganisms is important for success of long-term spaceflight. In a previous study using the high aspect ratio vessel bioreactor, we showed that the yeast species Saccharomyces cerevisiae underwent a significant phenotypic response when grown in modeled microgravity, which was reflected in the analysis of gene expression profiles. In this study, we establish that Candida albicans responds to SMG in a similar fashion, demonstrating that there is a conserved response among yeast to this environmental stress. We also report that the growth of C. albicans in SMG results in a morphogenic switch that is consistent with enhanced pathogenicity. Specifically, we observed an increase in filamentous forms of the organism and accompanying changes in the expression of two genes associated with the yeasthyphal transition. The morphological response may have significant implications for astronauts＇ safety, as the fungal pathogen may become more virulent during spaceflight.

关键词： yeast Candida albicans SMG HARV HWP1 YWP1

Effects of afforestation of agricultural land with grey alder(Alnus incana(L.) Moench)on soil chemical properties, comparing two contrasting soil groups

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Forest Ecosystems 2020年第3期7卷 489-498页

作者： Oļģerts Nikodemus dārta Kaupe Imants Kukuļs Guntis Brūmelis Raimonds Kasparinskis Iluta dauškaneand Agita Treimane Faculty of Geography and Earth Sciences University of LatviaJelgavas iela 1RigaLV-1004Latvia Faculty of Biology University of LatviaJelgavas iela 1RigaLV-1004Latvia

Background: Natural afforestation of former agricultural lands with alder species is common in Europe. Symbiotic nitrogen fixation by actinomycetes associated with alder species has been widely used for improvement of soil properties of abandoned agricultural lands, but relatively little is known of the interactions of these processes with soil type and chemical composition. We conducted a space-for time study with soil sampling under and outside grey alder tree canopies on two different soil groups to explore effects of colonisation of former agricultural lands by alder on soil ***: The results were analysed using analysis of variance. during the first 25 years after afforestation of former agricultural lands there was a significant increase in content of Ctot, Ntot, K+, Fe3+, Mn2+and available P in the topsoil(0–10 cm and 11–20 cm) of dystric Arenosols soils, which are deficient in organic matter. Such trends were not evident in organic matter rich Endostagnic Umbrisols soils, in which exchangeable K+concentration decreased and exchangeable Fe3+and Al3+concentration ***: The results show that the effects of grey alder on soil chemical properties depend on initial soil properties. The invasion of agricultural land by grey alder leads to spatial variability of soil chemical properties creating a mosaic pattern.

关键词： Afforestation Grey alder Soil properties Umbrisols Arenosols Topsoil

Initial evaluations of a Gulf of Mexico/Caribbean ocean forecast system in the context of the deepwater Horizon disaster

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Frontiers of Earth Science 2015年第4期9卷 605-636页

作者： Edward d. ZARON Patrick J. FITZPATRICK Scott L. CROSS John M. HARdING Frank L. BUB Jerry d. WIGGERT dong S. KO Yee LAU Katharine WOOdARd Christopher N. K. MOOERS department of Civil and Environmental Engineering Portland State University Portland OR 97207 USA Geosystems Research Institute Mississippi State University MSU Science & Technology Center Stennis Space Center MS 39529 USA NOAA National Coastal data development Center Stennis Space Center MS 29412 USA Northern Gulf Institute Mississippi State University MSU Science & Technology Center Stennis Space Center MS 39529 USA unaffiliated retired from the Naval Oceanographic Office Stennis Space Center MS 39522 USA department of Marine Science University of Southern Mississippi Stennis Space Center MS 39529 USA Oceanography division Naval Research Laboratory Stennis Space Center MS 39529 USA

In response to the deepwater Horizon （dwH） oil spill event in 2010, the Naval Oceanographic Office deployed a nowcast-forecast system covering the Gulf of Mexico and adjacent Caribbean Sea that was designated Americas Seas, or AMSEAS, which is documented in this manuscript. The dwH disaster provided a challenge to the application of available ocean-forecast capabilities, and also generated a historically large observational dataset. AMSEAS was evaluated by four complementary efforts, each with somewhat different aims and approaches： a university research consortium within an Integrated Ocean Observing System （IOOS） testbed; a petroleum industry consortium, the Gulf of Mexico 3-d Operational Ocean Forecast System Pilot Prediction Project （GOMEX-PPP）; a British Petroleum （BP） funded project at the Northern Gulf Institute in response to the oil spill; and the Navy itself. Validation metrics are presented in these different projects for water temperature and salinity profiles, sea surface wind, sea surface temperature, sea surface height, and volume transport, for different forecast time scales. The validation found certain geographic and time biases/errors, and small but systematic improvements relative to earlier regional and global modeling efforts. On the basis of these positive AMSEAS validation studies, an oil spill transport simulation was conducted using archived AMSEAS nowcasts to examine transport into the estuaries east of the Mississippi River. This effort captured the influences of Hurricane Alex and a non-tropical cyclone off the Louisiana coast, both of which pushed oil into the western Mississippi Sound, illustrating the importance of the atmospheric influence on oil spills such as dwH.

关键词： Gulf of Mexico deepwater Horizon ocean forecasting skill assessment

Criticality, adaptability and early-warning signals in time series in a discrete quasispecies model

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Frontiers in Biology 2013年第2期8卷 247-259页

作者： R. FOSSION d. A. HARTASANCHEZ O. RESENdIS-ANTONIO A. FRANK Instituto Nacional de Geriatrla Periferico Sur No. 2767 Col. San Jeronimo Lidice Del. Magdalena Contreras 10200 Mexico D.E Mexico Centro de Ciencias de la Complejidad (C3) Universidad Nacional Autonoma de Mkxico 04510 Mexico D.E Mexico Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra) 08003 Barcelona Catalonia Spain Systems Biology Group lnstituto Nacional de Medicina Genomica (INMEGEN) Mexico Instituto de Ciencias Nucleares Universidad Nacional Autonoma de Mexico 04510 Mexico D.E Mexico

Complex systems from different fields of knowledge often do not allow a mathematical description or modeling, because of their intricate structure composed of numerous interacting components. As an alternative approach, it is possible to study the way in which observables associated with the system fluctuate in time. These time series may provide valuable information about the underlying dynamics. It has been suggested that complex dynamic systems, ranging from ecosystems to financial markets and the climate, produce generic early-warning signals at the ＂tipping points,＂ where they announce a sudden shift toward a different dynamical regime, such as a population extinction, a systemic market crash, or abrupt shifts in the weather. On the other hand, the framework of Self- Organized Criticality （SOC）, suggests that some complex systems, such as life itself, may spontaneously converge toward a critical point. As a particular example, the quasispecies model suggests that RNA viruses self-organize their mutation rate near the error-catastrophe threshold, where robustness and evolvability are balanced in such a way that survival is optimized. In this paper, we study the time series associated to a classical discrete quasispecies model for different mutation rates, and identify early-warning signals for critical mutation rates near the error-catastrophe threshold, such as irregularities in the kurtosis and a significant increase in the autocorrelation range, reminiscent of 1/f noise. In the present context, we find that the early-warning signals, rather than broadcasting the collapse of the system, are the fingerprint of survival optimization.

关键词： time series complexity early-warning signals quasispecies 1/f noise optimization

Uncovering current pyroregions in Italy using wildfire metrics

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Ecological Processes 2022年第1期11卷 259-275页

作者： Mario Elia Vincenzo Giannico davide Ascoli Juan Pablo Argañaraz Marina d’Este Giuseppina Spano Raffaele Lafortezza Giovanni Sanesi department of Agricultural and Environmental Sciences University of Bari A.MoroVia Amendola 165/A70126 BariItaly department of Agricultural Forest and Food SciencesUniversity of TurinLargo Braccini 210095 GrugliascoTOItaly Mario Gulich Institute for Advanced Space Studies(CONAE-UNC) CONICETRoute C45km 8CP 5187 Falda del CañeteCórdobaArgentina department of Geography The University of Hong KongCentennial CampusPokfulam RoadHong KongChina

Background:Pyrogeography is a major field of investigation in wildfire science because of its capacity to describe the spatial and temporal variations of fire *** propose a systematic pyrogeographic analytical approach to cluster regions on the basis of their *** employed the Affinity Propagation algorithm to cluster pyroregions using Italian landscape as a test bed and its current wildfire metrics in terms of density,seasonality and stand replacing fire ratio.A discussion follows on how pyrogeography varies according to differences in the human,biophysical,socioeconomic,and climatic ***:The algorithm identified seven different pyroregion *** main gradients were identified that partly explain the variability of wildfire metrics observed in the current ***,a gradient characterized by increasing temperatures and exposure to droughts,which coincides with a decreasing latitude,and second,a human pressure gradient displaying increasing population density in areas at lower *** drivers exerted a major influence on wildfire density,burnt area over available fuels and stand replacing,which were associated to warmdry climate and high human *** study statistically highlighted the importance of a North–South gradient,which represents one of the most important drivers of wildfire regimes resulting from the variations in climatic conditions but showing collinearity with socioeconomic aspects as ***:Our fully replicable analytical approach can be applied at multiple scales and used for the entire European continent to uncover new and larger *** could create a basis for the European Commission to promote innovative and collaborative funding programs between regions that demonstrate pyrosimilarities.

关键词： Pyrogeography Affinity propagation Forest Mediterranean basin Clustering

Influence of Co Content on Raman and Photoluminescence Spectra of Co doped ZnO Nanowires

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Journal of Materials Science & Technology 2012年第4期28卷 313-316页

作者： Y.Q. Chang P.W. Wang S.L. Ni Y. Long X.d. Li School of Materials Science anti Engineering University of Science and Technology Beijing Beijing 100083 China department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Co doped ZnO nanowires with different Co contents have been fabricated by a chemical vapor deposition method. X-ray diffraction results show that all the samples are of single phase and crystallize in wurtzite ZnO structure. The lattice parameter a increases with increasing Co content, while the parameter c has no obvious change with increasing Co. Raman spectra show that the nonpolar E2（High） mode becomes broad and weak with the doping of Co, which indicates that the incorporation of Co causes structural disorder in the crystalline columnar ZnO lattice. The photolurninescence spectra exhibit that the position of the ultraviolet emission shifts to short wavelength and the intensity decreases with increasing Co. The green emission is affected by two contrary factors. It is increased by the introduced defects, but suppressed by the interaction between Co doping and native defects and the later affects it more significantly.

关键词： Co doped ZnO nanowires Raman Photoluminescence Single phase

COVId-19 outbreak and surgical practice: The rationale for suspending non-urgent surgeries and role of testing modalities

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World Journal of Gastrointestinal Surgery 2020年第6期12卷 259-268页

作者： Andrew d Grubic Shahin Ayazi Javad Zebarjadi Hamed Tahmasbi Khosro Ayazi Blair A Jobe Esophageal and Lung Institute Department of SurgeryAllegheny Health NetworkPittsburghPA 15224United States department of Surgery Imam Hossein HospitalShahid Beheshti University of Medical SciencesTehran ***Iran

One-hundred years after the 1918-19 H1N1 flu pandemic and 10 years after the 2009 H1N1 flu pandemic, another respiratory virus has now inserted itself into the human population. Severe acute respiratory syndrome coronavirus has become a critical challenge to global health with immense economic and social disruption. In this article we review salient aspects of the coronavirus disease2019(COVId-19) outbreak that are relevant to surgical practice. The emphasis is on considerations during the pre-operative and post-operative periods as well as the utility and limitations of COVId-19 testing. The focus of the media during this pandemic is centered on predictive epidemiologic curves and models. While epidemiologists and infectious disease physicians are at the forefront in the fight against COVId-19, this pandemic is also a "stress test" to evaluate the capacity and resilience of our surgical community in dealing with the challenges imposed to our health system and society. As recently pointed out by dr. Anthony Fauci,the virus decides the timelines in the models. However, the models can also change based on our decisions and behavior. It is our role as surgeons, to make every effort to bend the curves against the virus’ will.

关键词： COVId-19 SARS-CoV-2 Surgery Pandemic Predictive model diagnosis

Endothelial impairment evaluation by peripheral arterial tonometry in pediatric endocrinopathies:A narrative review

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World Journal of diabetes 2021年第6期12卷 810-826页

作者： Alberto La Valle Marco Crocco decimo Silvio Chiarenza Mohamad Maghnie Giuseppe d'Annunzio Pediatric Clinic and Endocrinology IRCCS Istituto Giannina GasliniGenoa16147Italy Pediatric Clinic and Endocrinology IRCCS Giannina Gaslini InstituteDepartment of NeuroscienceRehabilitationOphthalmologyGeneticsMaternal and Child Health University of GenoaGenoa16147Italy

Endothelial dysfunction(Ed)is characterized by an imbalance between vasodilator and vasoconstriction *** pathological conditions clinically diagnosed in childhood and adolescence are characterized by Ed and increased risk for early development of microangiopathic and macroangiopathic impairment,in particular type 1 diabetes mellitus(T1dM),T2dM,obesity,metabolic syndromeand pituitary dysfunction associated to various *** recently insulin resistance following chemotherapy or radiotherapy for tumors,bone marrow transplantation for hematological malignancies(i.e.,cancer survivors),or immunosuppressive treatment for solid organ transplantation has been *** of Ed by means of non-invasive techniques is the gold standard for early Ed detection before clinical *** is aimed to recognize patients at risk and to avoid the development and progression of more serious *** hyperemia-peripheral artery tonometry is a noninvasive technique to assess peripheral endothelial function by measuring modifications in digital pulse volume during reactive hyperemia,and represents a non-invasive,reproducible and operator-independent tool able to detect precocious *** narrative review aimed to provide an overview of the most important papers regarding Ed detection by EndoPat 2000 in children and adolescents with different endocrine diseases.A comprehensive search of English language articles was performed in the MEdLINE database without using other search filters except the publication interval between 2005 and 2020.

关键词： Pediatric diabetes mellitus Pediatric endocrinopathies Metabolic syndrome Cancer survivors Endothelial dysfunction Peripheral artery tonometry

初次全膝关节置换术治疗老年胫骨平台骨折:文献回顾与我们的经验

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临床骨科杂志 2024年第1期27卷 132-132页

作者： SABATINI L APRATO A CAMAZZOLA d 胡孔足(摘译) 不详

老年人胫骨平台骨折的治疗非常具有挑战性,内固定术后继发创伤性关节炎,需要进行关节置换术比例非常高。2015~2019年,作者对11例外伤之前就合并骨关节炎的老年胫骨平台骨折患者进行全膝关节置换术,平均随访28个月。根据骨折类型和韧带情... 详细信息

老年人胫骨平台骨折的治疗非常具有挑战性,内固定术后继发创伤性关节炎,需要进行关节置换术比例非常高。2015~2019年,作者对11例外伤之前就合并骨关节炎的老年胫骨平台骨折患者进行全膝关节置换术,平均随访28个月。根据骨折类型和韧带情况,6例使用后稳定型假体,5例使用半限制性假体,末次随访KSS评分依次为(83±16)分和(74±15)分。未见假体松动。1例并发感染,1例并发假体周围骨折。

关键词：胫骨平台骨折创伤性关节炎关节置换术假体周围骨折骨关节炎末次随访内固定术后文献回顾