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Influence of agriculture and aquaculture activities on the response of autotrophic picoplankton in Laguna Macapule, Gulf of California (Mexico)

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Ecological Processes 2017年第1期6卷 41-51页

作者： Aída Martínez-López cristian Hakspiel-Segura Diana Cecilia Escobedo-Urías Bárbara González-acosta Centro Interdisciplinario de Ciencias Marinas-IPN(CICIMAR) Av.IPN s/nCol.Playa Palo de Santa RitaLa PazB.C.S.23096Mexico Centro de Interdisciplinario de Investigación para el Desarrollo Integral Regional (CIIDIR–Unidad Sinaloa)Bulevar Juan de Dios Bátiz Paredes 250Col.San JoachinGuasaveSinaloa 81101Mexico

Introduction:The lagoon is a component of coastal zones,whose populations of autotrophic picoplankton(APP)remain largely *** lagoons display high-nutrient productivity and additionally may also be subjected to anthropogenic *** study selected Laguna Macapule,located on the eastern shore in the mid-region of the Gulf of California,due to the fact that a drainage network servicing the surrounding agricultural region(>230,000 hectares under cultivation)directs irrigation runoff,shrimp farm effluents,and urban wastewater containing large quantities of nutrients to be discharged into this *** propose to identify the APP’s response to various types of environmental and anthropogenic influence in this highly impacted coastal ***:Two sites(separated by 2.7 km)were monitored from December 2007 to December ***,located at the entrance to Laguna Macapule(oceanic influence)and the other a discharge canal(eutrophic conditions)inside the lagoon at El Tortugó***:APP was the numerically dominant phytoplankton fraction(15×106 to 620×106 cells L−1)with coccoidal cyanobacteria as the dominant fraction throughout the *** levels were reached in spring-early autumn and they were the second largest contributor to *** of APP cells corresponds to the lagoon’s eutrophic *** numbers and a higher average of APP were recorded at the El Tortugón channel during the warm season(months with SST higher than 24°C).The general positive relationship of the APP’s annual cycle at both sites as well as a negative relationship with heterotrophic nanoflagellates(HNF)abundance,supports the idea that natural forcing,in particular sea surface temperature(SST)is the predominant influences on APP’s seasonal ***:Distinguishable significant differences in APP abundances and nutrients were recognizable between the two *** interplay of these variables contributed to lower densities of APP in winter and high de

关键词： Aquaculture Autotrophic picoplankton Eutrophic conditions Heterotrophic ciliates Heterotrophic nanoflagellates Urea

Surgical management of peritonitis secondary to acute superior mesenteric artery occlusion

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World Journal of Gastroenterology 2014年第29期20卷 9936-9941页

作者： Stefan acosta Vascular Centre Malm?Sk?ne University Hospital

Diagnosis of acute arterial mesenteric ischemia in the early stages is now possible using modern computed tomography with intravenous contrast enhancement and imaging in the arterial and/or portal *** patients have acute superior mesenteric artery(SMA)occlusion,and a large proportion of these patients will develop peritonitis prior to mesenteric revascularization,and explorative laparotomy will therefore be necessary to evaluate the extent and severity of intestinal ischemia,and to perform bowel *** establishment of a hybrid operating room in vascular units in hospitals is most important to be able to perform successful intestinal *** review outlines current frontline surgical strategies to improve survival and minimize bowel morbidity in patients with peritonitis secondary to acute SMA *** laparotomy needs to be performed *** treatment is based upon intestinal revascularization followed by bowel *** no vascular imaging has been carried out,SMA angiography is *** case of embolic occlusion of the SMA,open embolectomy is performed followed by *** case of thrombotic occlusion,the occlusive lesion can be recanalized retrograde from an exposed SMA,the guidewire snared from either the femoral or brachial artery,and stented with standard devices from these access *** resections and sometimes gall bladder removal due to transmural infarctions are performed at initial laparotomy,leaving definitive bowel reconstructions to a planned second look laparotomy,according to the principles of damage control *** with peritonitis secondary to acute SMA occlusion should be managed by both the general and vascular surgeon,and a hybrid revascularization approach is of utmost importance to improve outcomes.

关键词： Acute mesenteric ischemia Peritonitis Explorative laparotomy Endovascular treatment Hybrid revascularization Superior mesenteric artery occlusion

The Role of PIN Auxin Efflux Carriers in Polar Auxin Transport and Accumulation and Their Effect on Shaping Maize Development

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Molecular Plant 2012年第4期5卷 787-798页

作者： cristian Forestan Serena Varotto Department of Environmental Agronomy and Crop Science--University of Padova Viale dell'Universita 16 35020 Legnaro (PD) Italy

In plants, proper seed development and the continuing post-embryonic organogenesis both require that dif- ferent cell types are correctly differentiated in response to internal and external stimuli. Among internal stimuli, plant hormones and particularly auxin and its polar transport （PAT） have been shown to regulate a multitude of plant phys- iological processes during vegetative and reproductive development. Although our current auxin knowledge is almost based on the results from researches on the eudicot Arabidopsis thaliana, during the last few years, many studies tried to transfer this knowledge from model to crop species, maize in particular. Applications of auxin transport inhibitors, mutant characterization, and molecular and cell biology approaches, facilitated by the sequencing of the maize genome, allowed the identification of genes involved in auxin metabolism, signaling, and particularly in polar auxin transport. PIN auxin efflux carriers have been shown to play an essential role in regulating PAT during both seed and post-embryonic development in maize. In this review, we provide a summary of the recent findings on PIN-mediated polar auxin transport during maize development. Similarities and differences between maize and Arabidopsis are analyzed and discussed, also considering that their different plant architecture depends on the differentiation of structures whose development is con- trolled by auxins.

关键词： auxin PIN-formed auxin efflux carrier PAT Polar Auxin Transport kernel development meristem organ-ogenesis Zea mays.

Degenerate Nonlinear Elliptic Equations Lacking in Compactness

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 53-72页

作者： Maria MALIN cristian UDREA Department of Mathematics University of Craiova

In this paper, the authors prove the existence of solutions for degenerate elliptic equations of the form-div(a(x)▽_p u(x)) = g(λ, x, |u|^(p-2)u) in R^N, where ▽_pu =|▽u|^(p-2)▽u and a(x) is a degenerate nonnegative weight. The authors also investigate a related nonlinear eigenvalue problem obtaining an existence result which contains information about the location and multiplicity of eigensolutions. The proofs of the main results are obtained by using the critical point theory in Sobolev weighted spaces combined with a Caffarelli-Kohn-Nirenberg-type inequality and by using a specific minimax method, but without making use of the Palais-Smale condition.

关键词： Degenerate equations p-Laplacian Sobolev weighted spaces Mountain-pass theorem

Dynamic Analysis for the Global Performance of An SPM-Feeder-Cage System Under Waves and Currents

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China Ocean Engineering 2015年第3期29卷 415-430页

作者： cristian CIFUENTES M.H.KIM Ocean Engineering Program Department of Civil Engineering Texas A&M University College Station

In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodynamics coefficients of the vessel are calculated by using a 3D diffraction/radiation panel program. First- and second-order wave forces are included in the calculations. Morison equation is used to compute the drag force on line elements representing the net. Drag coefficients are determined at every time step in the simulation considering the relative normal velocity between the structural elements and the fluid flow. The dynamic response of the coupled system is analyzed for various environments and net materials. The results of the study show the effects of solidity ratio of the net and vertical positions of the cage on the overall dynamic response of the system, confirming the viability of this type of configuration for future development of offshore aquaculture in deep waters.

关键词： offshore aquaculture SPM(single point mooring) feeder vessel connecting lines operational/survival environment drag force equivalent net cage grouping net modeling line tensions solidity ratio

A high Q terahertz metamaterial absorber using concentric elliptical ring resonators for harmful gas sensing applications

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Defence Technology（防务技术） 2023年第4期22卷 69-73页

作者： Bhargav Appasani Avireni Srinivasulu cristian Ravariu Department of Electronics Engineering Kalinga Institute of Industrial TechnologyBhubaneswarIndia Department of Electronics Engineering K R Mangalam UniversityGurgaonIndia Department of Electronic Devices Circuits and ArchitecturesPolytechnic University of BucharestBucharestRomania

A nearly perfect metamaterial absorber is proposed that can find utility in terahertz sensing *** design consists of two concentric elliptical ring resonators(ERRs)whose parameters are appropriately set to achieve dual band absorption with near perfect *** first absorption band at 3.62 THz having a Q-factor of 51.7 was caused due to the currents in the outer and inner *** second absorption peak at 3.814 THz having a Q factor of 1411.11 was a consequence of currents flowing across the gap between the two concentric ***,it is observed that the absorption bands are sensitive to the variation in refractive index of the surrounding *** sensitivity's in the absorption bands are 3 THz/RIU and 3.59 THz/RIU respectively.A sensor is proposed based on this design to detect harmful gases,which is demonstrated for detection of Methane and *** Q-factor and high sensitivity of the narrow band makes the design an excellent sensor for detecting variations in the refractive index.

关键词： Refractive index Plasma frequency Metamaterials Terahertz absorption Q-factor Gas sensing

Redox regulation of mammalian sperm capacitation

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Asian Journal of Andrology 2015年第4期17卷 583-590页

作者： cristian O'Flaherty Urology Research Laboratory Surgery Department (Urology Division) Faculty of Medicine McGill University Montreal Quebec Canada The Research Institute McGillUniversity Health Centre Montreal Quebec Canada.

Capacitation is a series of morphological and metabolic changes necessary for the spermatozoon to achieve fertilizing ability. One of the earlier happenings during mammalian sperm capacitation is the production of reactive oxygen species （ROS） that will trigger and regulate a series of events including protein phosphorylation, in a time-dependent fashion. The identity of the sperm oxidase responsible for the production of ROS involved in capacitation is still elusive, and several candidates are discussed in this review. Interestingly, ROS-induced ROS formation has been described during human sperm capacitation. Redox signaling during capacitation is associated with changes in thiol groups of proteins located on the plasma membrane and subcellular compartments of the spermatozoon. Both, oxidation of thiols forming disulfide bridges and the increase on thiol content are necessary to regulate different sperm proteins associated with capacitation. Reducing equivalents such as NADH and NADPH are necessary to support capacitation in many species including humans. Lactate dehydrogenase, glucose-6-phospohate dehydrogenase, and isocitrate dehydrogenase are responsible in supplying NAD （P） H for sperm capacitation. Peroxiredoxins （PRDXs） are newly described enzymes with antioxidant properties that can protect mammalian spermatozoa; however, they are also candidates for assuring the regulation of redox signaling required for sperm capacitation. The dysregulation of PRDXs and of enzymes needed for their reactivation such as thioredoxin/thioredoxin reductase system and glutathione-S-transferases impairs sperm motility, capacitation, and promotes DNA damage in spermatozoa leading to male infertility.

关键词： dehydrogenases oxidases peroxiredoxins reactive oxygen species spermatozoa thiols thioredoxins

Dispersed multiphase flows:advances in measuring,simulation and modeling

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Acta Mechanica Sinica 2022年第8期38卷 1-3页

作者： cristian Marchioli Lihao Zhao Department of Engineering and Architecture University of UdineUdine33100Italy Key Laboratory of Applied Mechanics Department of Engineering MechanicsTsinghua UniversityBeijing100084China

Dispersed multiphase flows are commonly encountered in a wide variety of natural and industrial applications,from sedimentation in rivers and plankton surfacing in oceanic flows to fluidized bed in chemical reactors and pneumatic conveying *** these flows,a dispersed phase(con-sisting of particles,droplets and/or bubbles)is transported by a carrier *** interaction between the phases re-sults in complex dynamics(e.g.,transport,spatial clustering,and deformation or break-up)that is rich in physics and poses a wide spectrum of theoretical,computational,and experimental *** challenges are at the very core of the research efforts made by the multiphase flow community over the past decades.

关键词： multiphase flows dispersed

New unexpected role for Wolfram Syndrome protein WFS1:a novel therapeutic target for Alzheimer’s disease?

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Neural Regeneration Research 2023年第7期18卷 1501-1502页

作者： Shuo Chen Diana acosta Hongjun Fu Department of Neuroscience Biomedical Sciences Graduate ProgramThe Ohio State UniversityColumbusOHUSA Department of Neuroscience The Ohio State UniversityColumbusOHUSA

Selective vulnerability of excitatory neurons in Alzheimer’s disease(AD):AD is the most common form of dementia;however,the pathogenesis of AD is largely *** of the characteristic features of AD is the formation of intracellular neurofibrillary tangles(NFTs).NFTs are abnormal accumulates of misfolded tau protein,which may eventually cause neuronal death and neurodegeneration(Jack et al.,2018).In the early stages of AD progression,not all neurons are equally vulnerable to tau *** studies have shown that large pyramidal neurons in the entorhinal cortex(EC)are specifically vulnerable to pathological tau accumulation(Fu et al.,2017).This selective vulnerability of excitatory neurons to tau pathology is one of the fundamental questions needed to be answered in AD research.

关键词： Alzheimer tau cortex