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Anthropogenic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmospheric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DoNG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Department of Atmospheric Sciences Yunnan UniversityKunming 650500China National Centre for Atmospheric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the present day(pD,1994–2011) is double that in the early period(Ep, 1964–81);the duration of HDEs increases by 60%. Climate experiments with the Met office Unified Model(MetUM-GoML2) are used to estimate the contributions of anthropogenic forcing to HDE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HDE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad F.Zueter Mohammad Zolfagharroshan Navid Bahrani Agus p.Sasmito Department of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada Department of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental *** this study,a novel AGF technique is proposed deploying available cold wind in cold *** is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study provides mining practitioners with sustainable solutions of underground AGF.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions

performance and Emission Characteristics of a CRDI Diesel Engine Fuelled by Sio_(2) Nanoparticle-Waste Fat Biodiesel Blends

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China petroleum processing & petrochemical Technology 2024年第1期26卷 56-66页

作者： Babu Aurtherson p Dinesh Babu Munuswamy Ravikumar Jayabal Yuvarajan Devarajan Department of Mechanical Engineering Mahat Amma Institute of Engineering and TechnologyPudukkottaiTamil NaduIndia Department of Mechanical Engineering Rajalakshmi Institute of TechnologyChennaiTamil NaduIndia Department of Thermal Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennaiTamil NaduIndia

This study investigates the use of waste fat biodiesel(WFB)from the leather industry as a substitute for diesel ***,it examines the diesel engine performance of WFB,a blend of WFB and diesel(B50),and different blends of WFB and silicon dioxide(Sio_(2))nanoparticles(B50Sio_(2)40,B50Sio_(2)80,and B50Sio_(2)120μg/g).The results indicate that the B50Sio_(2)120 blend increases brake thermal efficiency by 10.03%compared to pure biodiesel but falls 1.93%short of neat ***,the B50Sio_(2)120 mixture reduces smoke,hydrocarbon,and carbon monoxide emissions by 31.87%,34.14%,and 43.97%respectively,compared to ***,the B50Sio_(2)120 blend shows a 4.91%increase in nitrogen oxide emissions compared to diesel.

关键词： waste fat transesterification biodiesel silicon dioxide emission

A 3D In-vitro model of the human dentine interface shows long-range osteoinduction from the dentine surface

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International Journal of oral Science 2024年第2期16卷 225-237页

作者： William Macalester Asme Boussahel Rafael o.Moreno-Tortolero Mark R.Shannon Nicola West Darryl Hill Adam perriman School of Cellular and Molecular Medicine Biomedical Sciences BuildingUniversity of BristolUniversity WalkBristolUnited Kingdom Bristol Centre for Functional Nanomaterials HH Wills Physics LaboratoryUniversity of BristolTyndall AvenueBristolUnited Kingdom Centre for protolife Research School of ChemistryUniversity of BristolCantocks CloseBristolUnited Kingdom Max planck-Bristol Centre for Minimal Biology School of ChemistryUniversity of BristolBristolUnited Kingdom periodontology Bristol Dental SchoolUniversity of BristolLower Maudlin StreetBristolUnited Kingdom

Emerging regenerative cell therapies for alveolar bone loss have begun to explore the use of cell laden hydrogels for minimally invasive surgery to treat small and spatially complex maxilla-oral ***,the oral cavity presents a unique and challenging environment for in vivo bone tissue engineering,exhibiting both hard and soft periodontal tissue as well as acting as key biocenosis for many distinct microbial communities that interact with both the external environment and internal body systems,which will impact on cell fate and subsequent treatment ***,we design and bioprint a facile 3D in vitro model of a human dentine interface to probe the effect of the dentine surface on human mesenchymal stem cells(hMSCs)encapsulated in a microporous hydrogel *** demonstrate that the dentine substrate induces osteogenic differentiation of encapsulated hMSCs,and that both dentine andβ-tricalcium phosphate substrates stimulate extracellular matrix production and maturation at the gel-media interface,which is distal to the gel-substrate *** findings demonstrate the potential for long-range effects on stem cells by mineralized surfaces during bone tissue engineering and provide a framework for the rapid development of 3D dentine-bone interface models.

关键词： interface den surface

Sociodemographic determinants associated with breastfeeding in term infants with low birth weight in Latin American countries

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World Journal of Clinical pediatrics 2024年第1期13卷 141-149页

作者： Carlos Javier Avendaño-Vásquez Magda Liliana Villamizar-osorio Claudia Jazmin Niño-peñaranda Judith Medellín-olaya Nadia Carolina Reina-Gamba School of Nursing Antonio Nariño UniversityBogotá111511Colombia School of Nursing Universidad Cooperativa de ColombiaBucaramanga 102536Colombia School of Nursing Universidad Nacional de ColombiaColombia 111511Colombia

BACKGRoUND A progressive decrease in exclusive breastfeeding(BF)is observed in Latin America and the Caribbean compared with global *** possibility of being breastfed and continuing BF for>6 months is lower in low birth weight than in healthy-weight *** To identify factors associated with BF maintenance and promotion,with particular attention to low-and middle-income countries,by studying geographic,socioeconomic,and individual or neonatal health *** A scoping review was conducted in 2018 using the conceptual model of social determinants of health published by the Commission on Equity and Health Inequalities in the United *** extracted data with common characteristics were synthesized and categorized into two main themes:(1)Sociodemographic factors and proximal determinants involved in the initiation and maintenance of BF in low-birth-weight term infants in Latin America;and(2)individual characteristics related to the self-efficacy capacity for BF maintenance and adherence in low-birth-weight term *** This study identified maternal age,educational level,maternal economic capacity,social stratum,exposure to BF substitutes,access to BF information,and quality of health services as mediators for maintaining *** Individual self-efficacy factors that enable BF adherence in at-risk populations should be analyzed for better health outcomes.

关键词： Breastfeeding Low birth weight Latin America Self-efficacy Social determinants of health

A combined experimental and DEM investigation of grain interlocking in sheared granular assemblies

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particuology 2024年第7期90卷 436-451页

作者： Rui Lu Qiang Luo Tengfei Wang David p.Connolly Tao Xie School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-Speed Railway Engineering(Southwest Jiaotong University) Ministry of EducationChengdu 610031China School of Civil Engineering University of LeedsLeeds LS29JTUK Department of Civil Engineering McMaster UniversityHamiltonONCanada

Compacted granular material,integral to geotechnical engineering,undergoes translation,rotation,and interlocking when subject to shear displacements or external *** present study focuses on the interlocking of heterogeneous granular materials,a complex behavior influenced by gradation,compaction,and varying particle geometry,and has consequently received limited attention in existing *** address this research gap,we conducted an analysis on the effect of grain interlocking on the shear resistance of granular assemblies,using a combination of laboratory testing and the discrete element method(DEM).Initially,large-scale direct shear tests were conducted on gravel−sand mixes with varying degrees of compaction and normal *** of the mixes also underwent subsequent shear reversal to explore the differences in grain interlocking between the two shearing processes on the shear *** analyzing the laboratory results,a mesoscopic scale investigation was performed by replicating the test using discrete element *** facilitate this,granular particle geometries were measured using 3D laser scanning based on the physical lab ***,based on these scans,discrete element R-block and ball models were utilized to construct both the coarse and fine particles within the *** vibro-compaction was employed to regulate the degree of *** results indicate that an increase in vertical pressure,coupled with a zero dilatancy angle,results in a rising stress ratio,indicative of grain *** interlocking exhibits a positive correlation with both the coarse content and the degree of compaction,and varies depending on the shear *** interlocking progresses,the shear band,induced by particle movement,expands and is associated with reduced particle rotation near the shear *** study further reveals a consistent positive correlation between interlocking and the principal orientation angle of strong normal c

关键词： Granular material Interlocking Shear resistance Direct shear Discrete element method Vibro-compaction

Generation of lossy mode resonances(LMR)using perovskite nanofilms

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opto-Electronic Advances 2024年第2期7卷 33-40页

作者： Dayron Armas Ignacio R.Matias M.Carmen Lopez-Gonzalez Carlos Ruiz Zamarreño pablo Zubiate Ignacio del Villar Beatriz Romero Electrical Electronic and Communications Engineering DepartmentPublic University of NavarraPamplona 31006Spain Institute of Smart Cities(ISC) Public University of NavarraPamplona 31006Spain Experimental Science and Technology School Rey Juan Carlos UniversityMostoles 28933Spain

The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMR) devices based on perovskite coatings deposited on planar waveguides. perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMRs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. overall, this study highlights the potential of perovskite thin films for the development of novel LMR-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications.

关键词： perovskite thin films slab waveguide lossy mode resonance

In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis péter Nagy péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CANaps),or complete long period stacking ordered(LpSo)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CANaps/LpSo plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LpSo)phase Cluster arranged nanoplates(CANaps) Annealing Tension Dislocation density Hardening

Sickle cell retinopathy and systemic disease

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Annals of Eye Science 2024年第2期9卷 53-61页

作者： oladipupo o.Anibire Daniel ABrill Basil K.Williams Jr Meharry Medical College NashvilleTNUSA Department of ophthalmology University of Cincinnati College of MedicineCincinnatiOHUSA Cincinnati Eye Institute CincinnatiOHUSA Bascom palmer Eye Institute University of Miami Miller School of MedicineMiamiFLUSA

Sickle cell disease(SCD)is a widespread hemoglobinopathy that results in significant patient morbidity and *** occlusion can cause acute pain,acute chest syndrome,and avascular necrosis,while hemolysis and endothelial disruption can cause ischemic stroke,leg ulcers,pulmonary hypertension,and *** ocular and orbital structures can be affected by SCD ischemic events,including orbital bone infarction,ischemic optic neuropathy,retinal artery occlusion,hyphema,secondary glaucoma,sickle cell maculopathy,and sickle cell *** sickle cell retinopathy(pSR)is the most common cause of vision *** pSR can lead to macular ischemia,vitreous hemorrhage,and tractional retinal *** screening exams and multimodal imaging can lead to earlier detection of sickle cell retinopathy and improved patient *** patients undergoing vitreoretinal surgery may require coordination of care with hematologists to avoid ischemic *** hydroxyurea was the only United States Food and Drug Administration approved treatment for several decades,patients with SCD now have several more treatment *** the United States screening all infants for SCD,there can be delays in diagnosis and *** review article aims to provide an overview of sickle disease for the ophthalmologist,and to discuss emerging treatment options and current management of SCD ocular complications.

关键词： Sickle cell anemia sickle cell disease(SCD) sickle cell retinopathy retinal detachment vitreous hemorrhage(VH)