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Attack-resilient control for converter-based DC microgrids

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Global Energy Interconnection 2023年第6期6卷 751-757页

作者： Sen Tan Juan C.Vasquez josep.M.Guerrero Aalborg University Fredrik Bajers Vej 7KAalborg9220Denmark

In light of the growing integration of renewable energy sources in power systems,the adoption of DC microgrids has become increasingly popular,due to its simple structure,having no frequency,power factor ***,the dependence of DC microgrids on cyber-networks also makes them susceptible to *** cyberattacks can disrupt power system facilities and result in significant economic and loss of *** address this concern,this paper presents an attack-resilient control strategy for microgrids to ensure voltage regulation and power sharing with stable operation under cyber-attack on the *** paper first formulates the cyber-security problem considering a distributed generation based microgrid using the converter model,after which an attack-resilient control is proposed to eliminate the actuator attack impact on the *** state analysis and root locus validation illustrate the feasibility of the proposed *** effectiveness of the proposed control scheme is demonstrated through simulation results.

关键词： Cyber-attacks DC microgrids Resilient control

Square cavity flow driven by two mutually facing sliding walls

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第7期24卷 612-624页

作者： Bo AN josep.M.BERGADà Weimin SANG Dong LI F.MELLIBOVSKY School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of Science and Technology on Aerodynamic Design and Research Xi'an 710072China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China Department of Fluid Mechanics Universitat Politécnica de CatalunyaBarcelona 08034Spain Department of Physics Aerospace Engineering DivisionUniversitat Politécnica de CatalunyaBarcelona 08034Spain

We investigate the flow inside a 2D square cavity driven by the motion of two mutually facing walls independently sliding at different *** exploration,which employs the lattice Boltzmann method(LBM),extends on previous studies that had the two lids moving with the exact same speed in opposite *** there,here the flow is governed by two Reynolds numbers(Re_(T),Re_(B))associated to the velocities of the two moving *** convenience,we define a bulk Reynolds number Re and quantify the driving velocity asymmetry by a parameterα.Parameterαhas been defined in the rangeα∈[-π4,0]and a systematic sweep in Reynolds numbers has been undertaken to unfold the transitional dynamics path of the two-sided wall-driven cavity *** particular,the critical Reynolds numbers for Hopf and NeimarkSacker bifurcations have been determined as a function ofα.The eventual advent of chaotic dynamics and the symmetry properties of the intervening solutions are also analyzed and *** study unfolds for the first time the full bifurcation scenario as a function of the two Reynolds numbers,and reveals the different flow topologies found along the transitional path.

关键词： Two-sided wall-driven cavity Velocity ratios Transitions Flow topology Energy cascade

Characterization of hepatitis B virus X gene quasispecies complexity in mono-infection and hepatitis delta virus superinfection

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World Journal of Gastroenterology 2019年第13期25卷 1566-1579页

作者： Cristina Godoy David Tabernero Sara Sopena josep.Gregori Maria Francesca Cortese Carolina González Rosario Casillas Mar?al Yll Ariadna Rando Rosa López-Martínez josep.Quer Gloria González-Aseguinolaza Rafael Esteban Mar Riveiro-Barciela Maria Buti Francisco Rodríguez-Frías Liver Pathology Unit Departments of Biochemistry and Microbiology Hospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona Liver Unit Liver Disease Laboratory-Viral Hepatitis Vall d’Hebron Institut Recerca-Hospital Universitari Vall d'Hebron Universitat Autònoma de Barcelona Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) Instituto de Salud Carlos Ⅲ Roche Diagnostics SL Centro de Investigación Médica Aplicada (CIMA) Universidad de Navarra Liver Unit Department of Internal MedicineHospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona (UAB)

Hepatitis delta virus(HDV) seems to strongly suppress hepatitis B virus(HBV)replication, although little is known about the mechanism of this interaction. Both these viruses show a dynamic distribution of mutants, resulting in viral quasispecies. Next-generation sequencing is a viable approach for analyzing the composition of these mutant spectra. As the regulatory hepatitis B X protein(HBx) is essential for HBV replication, determination of HBV X gene(HBX)quasispecies complexity in HBV/HDV infection compared to HBV monoinfection may provide information on the interactions between these two *** To compare HBV quasispecies complexity in the HBX 5' region between chronic hepatitis delta(CHD) and chronic HBV mono-infected *** Twenty-four untreated patients were included: 7/24(29.2%) with HBeAgnegative chronic HBV infection(CI, previously termed inactive carriers), 8/24(33.3%) with HBeAg-negative chronic hepatitis B(CHB) and 9/24(37.5%) with CHD. A serum sample from each patient was first tested for HBV DNA *** HBX 5' region [nucleotides(nt) 1255-1611] was then PCR-amplified for subsequent next-generation sequencing(MiSeq, Illumina, United States). HBV quasispecies complexity in the region analyzed was evaluated using incidencebased indices(number of haplotypes and number of mutations), abundancebased indices(Hill numbers of order 1 and 2), and functional indices(mutation frequency and nucleotide diversity). We also evaluated the pattern of nucleotide changes to investigate which of them could be the cause of the quasispecies *** CHB patients showed higher median HBV-DNA levels [5.4 logIU/mL,interquartile range(IQR) 3.5-7.9] than CHD(3.4 logIU/mL, IQR 3-7.6)(P = n.s.)or CI(3.2 logIU/mL, IQR 2.3-3.5)(P < 0.01) patients. The incidence and abundance indices indicated that HBV quasispecies complexity was significantly greater in CI than CHB. A similar trend was observed in CHD patients, although only Hill numbers of order 2 showed

关键词： Hepatitis B virus Hepatitis delta virus Hepatitis B X gene Next-generation sequencing Viral quasispecies Hepatitis B virus-hepatitis delta virus interaction

Warming-induced phenological mismatch between trees and shrubs explains high-elevation forest expansion

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National Science Review 2023年第10期10卷 62-71页

作者： Xiaoxia Li Eryuan Liang J.Julio Camarero Sergio Rossi Jingtian Zhang Haifeng Zhu Yongshuo H.Fu Jian Sun Tao Wang Shilong Piao josep.Pe?uelas State Key Laboratory of Tibetan Plateau Earth System Environment and Resources (TPESER)Institute of Tibetan Plateau ResearchChinese Academy of Sciences Laboratoire sur les écosystèmes terrestres boréaux Département des Sciences FondamentalesUniversité du Québec à Chicoutimi Instituto Pirenaico de Ecología (IPE-CSIC) College of Water Sciences Beijing Normal University CREAF Cerdanyola del Valles CSIC Global Ecology Unit CREAF-CSIC-UAB

Despite the importance of species interaction in modulating the range shifts of plants,little is known about the responses of coexisting life forms to a warmer ***,we combine long-term monitoring of cambial phenology in sympatric trees and shrubs at two treelines of the Tibetan Plateau,with a meta-analysis of ring-width series from 344 shrubs and 575 trees paired across 11 alpine treelines in the Northern *** a spring warming of +1℃,xylem resumption advances by 2-4 days in trees,but delays by 3-8 days in *** divergent phenological response to warming was due to shrubs being3.2 times more sensitive than trees to chilling *** winters increased the thermal requirement for cambial reactivation in shrubs,leading to a delayed response to warmer *** meta-analysis confirmed such a mechanism across continental *** warming-induced phenological mismatch may give a competitive advantage to trees over shrubs,which would provide a new explanation for increasing alpine treeline shifts under the context of climate change.

关键词： chilling climate warming forcing treeline shift xylogenesis

Linking leaf elemental traits to biomass across forest biomes in the Himalayas

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Science China Earth Sciences 2024年第5期67卷 1518-1528页

作者： Nita DYOLA Eryuan LIANG josep.PEÑUELAS J.Julio CAMARERO Shalik Ram SIGDEL Sugam ARYAL Wentao LIN Xiang LIU Yongwen LIU Xingliang XU Sergio ROSSI State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Laboratoire sur lesécosystèmes terrestres boréaux Département des Sciences FondamentalesUniversitédu QuébecàChicoutimi555Boulevard de l′UniversitéChicoutimi(QC)G7H2B1Canada CSIC Global Ecology Unit CREAF-CSIC-UABBellaterraE-08193 CataloniaSpain CREAF Cerdanyola del VallèsE-08193 CataloniaSpain Instituto Pirenaico de Ecología(IPE-CSIC) Avenida Montañana 1005Zaragoza 50059Spain Friedrich-Alexander-Universität Erlangen-Nürnberg Institut für GeographieErlangen 91058Germany State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Plants require a number of essential elements in different proportions for ensuring their growth and *** elemental concentrations in leaves reflect the functions and adaptations of plants under specific environmental ***,less is known about how the spectrum of leaf elements associated with resource acquisition,photosynthesis and growth regulates forest biomass along broad elevational *** examined the influence of leaf element distribution and diversity on forest biomass by analyzing ten elements(C,N,P,K,Ca,Mg,Zn,Fe,Cu,and Mn)in tree communities situated every 100 meters along an extensive elevation gradient,ranging from the tropical forest(80 meters above sea level)to the alpine treeline(4200 meters above sea level)in the Kangchenjunga Landscape in eastern Nepal *** calculated communityweighted averages(reflecting dominant traits governing biomass,i.e.,mass-ratio effect)and functional divergence(reflecting increased trait variety,i.e.,complementarity effect)for leaf elements in a total of 1,859 trees representing 116 *** increasing mass-ratio effect and decreasing complementarity in leaf elements enhance forest biomass accumulation.A combination of elements together with elevation explains biomass(52.2%of the variance)better than individual elemental trait diversity(0.05%to 21%of the variance).Elevation modulates trait diversity among plant species in biomass *** promotes biomass at lower elevations,but reduces biomass at higher elevations,demonstrating an interaction between elevation and *** interaction between elevation and mass-ratio effect produces heterogeneous effects on biomass along the elevation *** research indicates that biomass accumulation can be disproportionately affected by elevation due to interactions among trait diversities across vegetation *** higher trait variation enhances the adaptation of species to environmental changes,it reduces

关键词： Ecosystem function Elevational gradient Functional diversity Functional traits Leaf elements Niche complementarity

Conservation and variability of hepatitis B core at different chronic hepatitis stages

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World Journal of Gastroenterology 2020年第20期26卷 2584-2598页

作者： Marcal Yll Maria Francesca Cortese Mercedes Guerrero-Murillo Gerard Orriols josep.Gregori Rosario Casillas Carolina González Sara Sopena Cristina Godoy Marta Vila David Tabernero josep.Quer Ariadna Rando Rosa Lopez-Martinez Rafael Esteban Mar Riveiro-Barciela Maria Buti Francisco Rodríguez-Frías Liver Pathology Unit Departments of Biochemistry and MicrobiologyHospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Liver Unit Liver Disease Laboratory-Viral HepatitisVall d'Hebron Institut Recerca-Hospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Department of Microbiology Hospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas Instituto de Salud Carlos ⅢMadrid 28029Spain Liver Unit Department of Internal MedicineHospital Universitari Vall d'HebronUniversitat Autónoma de BarcelonaBarcelona 08035Spain

BACKGROUND Since it is currently not possible to eradicate hepatitis B virus(HBV)infection with existing treatments,research continues to uncover new therapeutic *** core protein,encoded by the HBV core gene(HBC),intervenes in both structural and functional processes,and is a key protein in the HBV life *** this reason,both the protein and the gene could be valuable targets for new therapeutic and diagnostic ***,alterations in the protein sequence could serve as potential markers of disease *** To detect,by next-generation sequencing,HBC hyper-conserved regions that could potentially be prognostic factors and targets for new *** Thirty-eight of 45 patients with chronic HBV initially selected were included and grouped according to liver disease stage[chronic hepatitis B infection without liver damage(CHB,n=16),liver cirrhosis(LC,n=5),and hepatocellular carcinoma(HCC,n=17)].HBV DNA was extracted from patients’plasma.A region between nucleotide(nt)1863 and 2483,which includes HBC,was amplified and analyzed by next-generation sequencing(Illumina Mi Seq platform).Sequences were genotyped by distance-based discriminant *** and intergroup nt and amino acid(aa)conservation was determined by sliding window *** presence of nt insertion and deletions and/or aa substitutions in the different groups was determined by aligning the sequences with genotype-specific consensus *** Three nt(nt 1900-1929,2249-2284,2364-2398)and 2 aa(aa 117-120,159-167)hyper-conserved regions were shared by all the clinical *** groups showed a similar pattern of conservation,except for five nt regions(nt 1946-1992,2060-2095,2145-2175,2230-2250,2270-2293)and one aa region(aa 140-160),where CHB and LC,respectively,were less conserved(P<0.05).Some group-specific conserved regions were also observed at both nt(2306-2334 in CHB and 1935-1976 and 2402-2435 in LC)and aa(between aa 98-103 in CHB and 28-30 and 5

关键词： Hepatitis B virus Hepatitis B core gene Next-generation sequencing Genetic conservation Amino acid substitution Gene therapy Small interfering RNA

Estimating cropland carbon mitigation potentials in China affected by three improved cropland practices

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Journal of Mountain Science 2016年第10期13卷 1840-1854页

作者： LUN Fei josep.G.CANADELL HE Lu YANG Bo LIU Mou-cheng YUAN Zheng TIAN Mi LIU Jun-guo LI Wen-hua School of Nature Conservation Beijing Forestry UniversityOinghua East Road 35Beijing 100083China College of Resources and Environment Sciences China Agricultural UniversityBeijing 100193China Center of Land Policy and Law Beijing 100193China Global Carbon Project CSIRO Marine and Atmospheric ResearchGPO Box 3023CanberraACT2601Australia World Natural Heritage Conservation and Research Center Ministry of Housing and Urban-RuralNo.9 SanliheBeijing 10085China Beijing Academy of Social Sciences No.33 BeisihuanzhongluBeijing 100101China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences11A Datun RoadBeijing 100101China. School of Environmental Science and Engineering South University of Science and Technology of ChinaShenzhen 518055China

Agriculture is a large source of carbon emissions. The cropland practices of fertilizer substitution, crop straw and conservation tillage are beneficial and help to rebuild local soil carbon stocks and reduce soil carbon emissions, in addition to reducing the consumption of fertilizers and fossil fuels. These improved cropland practices can directly and indirectly mitigatecarbon emissions, benefiting the sustainability of croplands. For these three improved practices, we estimated carbon mitigation potentials in rice, wheat and maize croplands in China. The combined contribution of these practices to carbon mitigation was 38.8 Tg C yr-1, with fertilizer substitution, crop straw return, and conservation tillage contributing 26.6, 3.6 and 8.6 Tg C yr-1, respectively. Rice, wheat and maize croplands had potentials to mitigate 13.4, 11.9 and 15.5 Tg C yr-1, respectively, with the combined direct and indirectpotential of 33.8 and 5.0 Tg C yr-1. Because of differences in local climate and specific diets, the regional cropland carbon mitigation potentials differed greatly among provinces in China. In China, 18 provinces had a "target surplus" for which the carbon mitigation from these three practices was larger than the mitigation target set for 2020. At the national level, a net "target surplus"of 4.84 Tg C yr-1 would be attained for Chinese croplands with full implementation of the three improved practices. Regional cooperation must be developed to achieve carbon mitigation targets using such measures as carbon trading, establishing regional associations, and strengthening research programs to improve practices.

关键词： Cropland Carbon mitigation potential Cropland practices Regional cooperation China

Hypothesis testing by simulation of a medical study model using the expected net benefits criteria

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Health 2013年第3期5卷 364-374页

作者： Ismail Abbas Joan Rovira josep.Casanovas InLab FIB Universitat Politècnica de Catalunya BarcelonaTech Barcelona Spain InLab FIB Universitat Politècnica de Catalunya BarcelonaTech Barcelona Spain Universitat de Barcelona Barcelona Spain

Introduction: This work investigates whether to conduct a medical study from the point of view of the expected net benefit taking into account statistical power, time and cost. The hypothesis of this paper is that the expected net benefit is equal to zero. Methods: Information were obtained from a pilot medical study that investigates the effects of two diagnostic modalities, magnetic resonance imaging (MRI) and computerized axial tomography scanner (CT), on patients with acute stroke. Statistical procedure was applied for planning and contrasting equivalence, non-inferiority and inequality hypotheses of the study for the effectiveness, health benefits and costs. A statistical simulation model was applied to test the hypothesis that conducting the study would or not result in overall net benefits. If the null hypothesis not rejected, no benefits would occurred and therefore the two arms-patterns of diagnostic and treatment are of equal net benefits. If the null hypothesis is rejected, net benefits would occur if patients are diagnosed with the more favourable diagnostic modality. Results: For any hypothesis design, the expected net benefits are in the range of 366 to 1796 per patient at 80% of statistical power if conducting the study. The power depends on the monetary value available for a unit of health improvement. Conclusion: The statistical simulations suggest that diagnosing patients with CT will provide more favourable health outcomes showing statistically significant expected net benefits in comparison with MRI.

关键词： Statistics Simulation Hypothesis Testing Expected Net Benefits

Enzyme Kinetic Equations of Irreversible and Reversible Reactions in Metabolism

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Journal of Biosciences and Medicines 2014年第4期2卷 24-29页

作者： Santiago Imperial josep.J. Centelles Departament de Bioquímica i Biologia Molecular (Biologia) Facultat de Biologia Universitat de Barcelona Barcelona Spain

This paper compares the irreversible and reversible rate equations from several uni-uni kinetic mechanisms (Michaelis-Menten, Hill and Adair equations) and bi-bi mechanisms (single- and double- displacement equations). In reversible reactions, Haldane relationship is considered to be identical for all mechanisms considered and reversible equations can be also obtained from this rela- tionship. Some reversible reactions of the metabolism are also presented, with their equilibrium constant.

关键词： Adair Equation Enzyme Kinetics Equilibrium Constant Haldane Relationship Hill Equation Metabolism Michaelis Menten Equation Reversible Reactions