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Journal of Environmental Sciences 2022年第11期34卷 1-12页

作者： Xiang-Yang Lou Roberto Boada veronica Verdugo Laura Simonelli Gustavo Pérez Manuel Valiente GTS-UAB Research Group Department of ChemistryFacultat de CiènciesUniversitat Autonoma de Barcelona08193 BellaterraSpain ALBA Synchrotron Carrer de la llum 2-26Cerdanyola del Valles08290 BarcelonaSpain Centro de Excelencia en Nanotecnologia Leitat ChileSantiago 7500724Chile

In this study, a commercial cube-shaped open-celled cellulose sponge adsorbent was modified by in-situ co-precipitation of superparamagnetic iron oxide nanoparticles(SPION) and used to remove As(V) from aqueous solutions. Fe K-edge X-ray absorption spectroscopy(XAS) and TEM identified maghemite as the main iron phase of the SPION nanoparticles with an average size 13 nm. Batch adsorption experiments at 800 mg/L showed a 63% increase of adsorption capacity when loading 2.6 wt.% mass fraction of SPION in the *** determination of the adsorption thermodynamic parameters indicated that the As(V) adsorption on the composite material is a spontaneous and exothermic *** K-edge XAS results confirmed that the adsorption enhancement on the composite can be attributed to the nanoparticles loaded. In addition, adsorbed As(V) did not get reduced to more toxic As(Ⅲ) and formed a binuclear corner-sharing complex with SPION. The advantageous cube-shape of the sponge-loaded SPION composite together with its high affinity and good adsorption capacity for As(V), good regeneration capability and the enhanceddiffusion attributed to its open-celled structure make this adsorbent a good candidate for industrial applications.

关键词： Adsorption Cube composite adsorbent Arsenate removal Regeneration X-ray absorption spectroscopy

Mortality from chronic liver disease:Recent trends and impact of the COVID-19 pandemic

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World Journal of Gastroenterology 2023年第26期29卷 4166-4173页

作者： Ugo Fedeli Claudio Barbiellini Amidei veronica Casotto Enrico Grande Mario Saia Alberto Zanetto Francesco Paolo Russo Epidemiological Department Azienda ZeroVeneto RegionPadova 35132Italy Integrated System for Health Social Assistance and WelfareNational Institute of StatisticsRome 00184Italy Clinical Governance Azienda ZeroVeneto RegionPadova 35132Italy Department of Surgery Oncology and Gastroenterology University of PaduaPadova 35128Italy Gastroenterology and Multivisceral Transplant Unit Azienda Ospedale-Universitàdi PadovaPadova 25128Italy

Prepandemic time trends in mortality from chronic liver disease(CLD)differed according to specific cause of death(decreasing for liver cirrhosis,stable or increasing for liver cancer),etiology(increasing for nonalcoholic fatty liver disease,generally decreasing for other etiologies),and world region(decreasing in areas with the highest burden of hepatitis B virus,increasing in Eastern Europe and other countries).The coronavirus disease 2019(COVID-19)pandemic affected mortality of patients with CLD both directly,with a higher risk for severe illness and death depending on age,stage and etiology of the disease,and indirectly,through social isolation and loss of support,harmful drinking,and difficulties in access to ***,only sparse data are available on variations in CLD as a cause of death during the *** the USA,in 2020-2021 a growth in mortality was registered for all liver diseases,more marked for alcoholic liver disease,especially among young people aged 25-44 years and in selected ethnic ***-19 related deaths accounted only for a minor part of the *** data from mortality registers of other countries are warranted,preferably adopting the so-called multiple cause-of-death approach,and extended to deaths attributed to viral hepatitis and liver cancer.

关键词： Mortality Multiple causes of death COVID-19 Chronic liver disease Liver cirrhosis Liver cancer

APEC Promoting to Develop FTAAP

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China's Foreign Trade 2014年第Z2期 10-11页

作者： veronica Cui

On November 10 and 11,the22nd Economic Leaders’Meeting of APEC will be held in *** October 16,ShenDanyang,the spokesman of the Ministry of Commerce(MOC),introduced the theme of this year’s APEC Economic Leaders’Mee... 详细信息

关键词： Regular Director cooperation innovative trading ad

Artificial gauge field switching using orbital angular momentum modes in optical waveguides

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Light(Science & Applications) 2020年第1期9卷 577-583页

作者： Christina Jorg Gerard Queralto Mark Kremer Gerard Pelegri Julian Schulz Alexander Szameit Georg von Freymann Jordi Mompartand veronica Ahufinger Physics Department and Research Center OPTIMAS Technische Universitat Kaiserslautern67663 KaiserslauternGermany Departament de Fisica Universitat Auto’noma de BarcelonaE-08193 BellaterraSpain Institut fur Physik Universitat RostockAlbert-Einstein-StraBe 2318059 RostockGermany Department of Physics and SUPA University of StrathclydeGlasgow G40NGUK Fraunhofer Institute for Industrial Mathematics ITWM 67663 KaiserslauternGermany

The discovery of artificial gauge fields controlling the dynamics of uncharged particles that otherwise elude the influence of standard electromagnetic fields has revolutionised the field of quantum ***,developing new techniques to induce these fields is essential to boost quantum simulation of photonic ***,we experimentally demonstrate the generation of an artificial gauge field in a photonic lattice by modifying the topological charge of a light beam,overcoming the need to modify the geometry along the evolution or impose external *** particular,we show that an effective magnetic flux naturally appears when a light beam carrying orbital angular momentum is injected into a waveguide lattice with a diamond chain *** demonstrate the existence of this flux,we measure an effect that derives solely from the presence of a magnetic flux,the Aharonov-Bohm caging effect,which is a localisation phenomenon of wavepackets due to destructive ***,we prove the possibility of switching on and off artificial gauge fields just by changing the topological charge of the input state,paving the way to accessing different topological regimes in a single structure,which represents an important step forward for optical quantum simulation.

关键词： gauge momentum orbital

Predictability of Hardness of the Heat Affect Zone in Aluminum Weldments Cooled in Palm Oil Based on Hardness of Similarly Cooled Mild Steel and Cast Iron Weldments

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Journal of Minerals and Materials Characterization and Engineering 2013年第6期1卷 358-362页

作者： Chukwuka Nwoye Stanley Nwakpa Agbo Alfred Chidume Nwambu uche Obialor Department of Mechanical Engineering Abia Polythecnic Aba Nigeria Department of Metallurgical and Materials Engineering Enugu State University of Science & Technology Enugu Nigeria Department of Metallurgical and Materials Engineering Nnamdi Azikiwe University Awka Nigeria

The predictability of hardness of the heat affected zone (HAZ) in aluminum weldments cooled in palm oil, based on hardness of similarly cooled mild steel and cast iron weldments has been ascertained. The general model: α = 1.2769? indicates that HAZ hardness of aluminium weldment is dependant on the ratio of product to sum of HAZ hardness of mild steel and cast iron weldments cooled in palm oil under the same conditions. The maximum deviations of the model-predicted HAZ hardness values α, μ and β from the corresponding experimental values αexp, μexp and βexp were less than 0.04% indicating the reliability and validity of the model.

关键词： Model Hardness Heat Affected Zone Aluminum Weldments Mild Steel Cast Iron

Systems Biology Approach Pinpoints Minimum Requirements for Auxin Distribution during Fruit Opening

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Molecular Plant 2019年第6期12卷 863-878页

作者： Xin-Ran Li Renske M.A.Vroomans Samantha Fox veronica A.Grieneisen Lars Φstergaard Athanasius F.M.Maree Crop Genetics John Innes Centre Norwich NR4 7UH UK Computational and Systems Biology John Innes Centre Norwich NR4 7UH UK Centre of Excellence in Computational and Experimental Developmental Biology Institute of Biotechnology University of Helsinki 00014 Helsinki Finland Cell and Developmental Biology John Innes Centre Norwich NR4 7UH UK School of Biosciences Cardiff University Cardiff CF10 3AX Wales UK

The phytohormone auxin is implied in steering various developmental decisions during plant morphogenesis in a concentration-dependent *** maxima have been shown to maintain meristematic activity,for example,of the root apical meristem,and position new sites of outgrowth,such as during lateral root initiation and *** recently,it has been demonstrated that sites of auxin minima also provide positional *** the developingArabidopsis fruit,auxin minima are required for correct differentiation of the valve *** remains unclear,however,how this auxin minimum is generated and ***,we employ a systems biology approach to model auxin transport based on experimental *** allows us to determine the minimal requirements for its *** simulations reveal that two alternative processes-which we coin "flux-barrier" and "flux-passage"-are both able to generate an auxin minimum,but under different parameter *** models are in principle able to yield similar auxin profiles but present qualitatively distinct patterns of auxin *** models were tested by tissue-specific inducible ablation,revealing that the auxin minimum in the fruit is most likely generated by a flux-passage *** predictions were further supported through 3D PIN localization imaging and implementing experimentally observed transporter *** such an experimental-modeling cycle,we predict how the auxin minimum gradually matures during fruit development to ensure timely fruit opening and seed dispersal.

关键词： auxin mathematical modeling polar auxin transport fruit development systems biology of patterning

CALLISTO facilities in Peru:spectrometer commissioning and observations of typeⅢsolar radio bursts

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Research in Astronomy and Astrophysics 2021年第6期21卷 329-336页

作者： Javier Alonso Rengifo veronica Loaiza-Tacuri Jose Bazo Walter Robert Guevara Day Seccion FIsica Departamento de CienciasPontificia Universidad Catolica del PeruAv.Universitaria 1801Lima 32Peru Direction de Astroflsica Comision National de Investigacion y Desarrollo AeroespacialCONIDALuis Felipe Villaran 1069LimaPeru Observatorio National Rua General Jose Cristino7720921-400 Sao CristovaoRio de JaneiroRJBrazil Facultad de Ciencias Ffsicas Universidad Nacional Mayor de San MarcosP.O.Box 14-149Lima 14Peru

The Astrophysics Directorate of CONIDA has installed two radio spectrometer stations belonging to the e-CALLISTO network in Lima,*** their strategic location near the Equator,it is possible to observe the Sun evenly throughout the whole *** receiver located at Pucusana,nearby the capital city of Lima,took data from October 2014 until August 2016 in the metric and decimetric bands looking for radio *** this period,this e-CALLISTO detector was unique in its time-zone *** asses the suitability of the sites and the performance of the antennas,we analyzed the radio ambient background and measured their radiation pattern and *** demonstrate the capabilities of the facilities for studying solar dynamics in these radio frequencies,we have selected and analyzed typeⅢSolar Radio *** study of this kind of burst helps to understand the electron beams traversing the solar corona and the solar atmospheric *** have characterized the most common radio bursts with the following mean values:a negative drift rate of-25.8±3.7 MHz s^(-1),a duration of 2.6±0.3 s and 35 MHz bandwidth in the frequency range of 114 to 174 *** addition,for some events,it was possible to calculate a global frequency drift which on average was 0.4±0.1 MHz s^(-1).

关键词： instrumentation:spectrographs Sun:radio radiation

Closing the Gaps in Disaster Management and Response:Drawing on Local Experiences with Cyclone Idai in Chimanimani,Zimbabwe

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International Journal of Disaster Risk Science 2020年第5期11卷 655-666页

作者： Nelson Chanza Pakama Q.Siyongwana Leizel Williams-Bruinders veronica Gundu-Jakarasi Chipo Mudavanhu Vusomuzi B.Sithole Albert Manyani Geography Department Bindura University of Science EducationBinduraZimbabwe School of Biology and Environmental Sciences University of Mpumalanga.Nelspruit-Mbombela 1200South Africa Department of Geosciences Nelson Mandela UniversityPort Elizabeth 6031South Africa Infrastructure Development Bank of Zimbabwe(IDBZ) HarareZimbabwe United Nations Development Program(UNDP) HarareZimbabwe

Cyclone Idai in Zimbabwe exposed deficiencies in the country's disaster management *** study uses a phenomenological case exploration of the experiences of local residents in Rusitu Valley following cyclone-induced floods that affected the area in March *** capturing narratives of participants who were recruited through chain referrals,the research intends to understand how local actors,utilizing their local-based response systems,managed to fill in the voids that characterize disaster management practice in *** show that the participation of local"heroes"and"Samaritans,"by deploying their social networks,norms,relationships,practices,and modest ingenuity,helped to speed up response times and minimize threats to lives and *** of the stories of local actors about their disaster experiences also gives a richer picture of the Cyclone Idai *** the community response system also facilitated the operation of external disaster management agencies,their premature withdrawal tended to weaken the trust and values existing in the area,and created tensions between the disaster-affected people and other *** the delays in formal responses by the government and other external relief agencies,the practices of local actors,although spontaneous and largely uncoordinated,offer rich insights into the design and development of disaster management regimes.

关键词： Cyclone Idai Flood disaster management Local knowledge and action Social networks Zimbabwe

COVID-19: Africa’s Challenge and the Need for a Paradigm Shift on the Use of Ventilators

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International Journal of Clinical Medicine 2020年第6期11卷 420-430页

作者： Jude-Kennedy C. Emejulu Yewande Anne Motunrayo Emejulu Enoch Ogbonnaya uche Department of Surgery Faculty of Medicine College of Health Sciences Nnamdi Azikiwe University Awka Nigeria Nnamdi Azikiwe University Teaching Hospital Nnewi Nigeria Department of Nursing Sciences Faculty of Health Sciences and Technology College of Health Sciences Nnamdi Azikiwe University Awka Nigeria Department of Surgery Faculty of Medical Sciences College of Medicine University of Nigeria Enugu Campus Enugu Nige-ria University of Nigeria Teaching Hospital Ituku Nigeria

Background: The December 2019 Chinese epidemic of Corona Virus Disease [COVID-19], which erupted in Wuhan, South China, was declared a pandemic, by the World Health Organization [WHO], on 12th January 2020. The worldwide spread from China was rapid, but Africa was the last port-of-call. Her first diagnosed case was two months after China’s, on 14th February, 2020 in Egypt. The morbidity and mortality rates have, however, remained lower in Africa than in the developed world, and analysts believe that it was more of a temporary respite, since Africa’s poor health infrastructure will become her eventual albatross. Methodology: Data were collected on COVID-19 and records of the socio-economic capacity of Africa by accessing the relevant previous and current peer-reviewed publications from multiple search engines on internet. The data were, then, collated and comparatively analyzed. Results: The available data revealed that Africa had, mostly, the milder forms of COVID-19, and so, morbidity and mortality were low. Her shrinking elderly population and hot climate were believed to be contributory, but lately, as the pandemic spread, the role of these factors was not exactly predictive. Being low on healthcare infrastructure, Africa could tenaciously leverage on the supportive and preventive measures prescribed by WHO, while the world awaited a vaccine. The role of ventilators in the care of critically ill patients, also, came under scrutiny as some workers were questioning the underlying pathology, and advocating a paradigm shift from high-tech positive end expiratory pressure ventilation to plasmapheresis and packed cell transfusion. Conclusion: Africa faces a huge challenge with COVID-19, but the predicted heavy mortalities may be reduced by some local confounding factors, control of spread and re-focusing of critical care away from the expensive and unavailable ventilators.

关键词： Blood Failure China Confirmed Cases Cytokine Storm Deaths Egypt Interleukin-6 as Biomarker Packed Cell Transfusion Respiratory Failure Plasmapheresis SARS-CoV-2 USA

Effect of Tin Tailings on Some Refractory Properties of Alumino-Silicates (Alkaleri) Clay

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Journal of Minerals and Materials Characterization and Engineering 2013年第2期1卷 29-32页

作者： Victor Sunday Aigbodion Clement uche Atuanya Chikaodi Cynthia Daniel Mkpume Department of Metallurgical and Materials Engineering Nnamdi Azikiwe University Awka Nigeria Department of Metallurgical and Materials Engineering University of Nigeria Nsukka Nigeria

The possibilities of upgrading some refractory properties of Alkaleri Clay (Alumino-silicates), found in Alkaleri Village, Bauchi State, Nigeria, by blending with tin tailings for the production of fireclay refractory bricks were investigated. Refractory properties such as: linear shrinkage, apparent porosity, bulk density, cold crushing strength and thermal shock resistance were tested with percentage additions of tin tailings from 5 - 30 wt% in the blend. The test was conducted using the standard test techniques in each case. The results were compared with standard refractory properties for fire clay bricks. Cold crushing strength, bulk density, refractoriness and thermal shock resistance of the bricks made from the blend clay increased, as the percentages of tin tailings increased. The Linear shrinkage and apparent porosity decreased as the percentages of tin tailings addition increased. All the values obtained from the blends are within the recommended values for dense fireclay bricks. Hence, dense fireclay can be produced from this blended.

关键词： Tin Talings Alkeri Clay Refractory Properties