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Stand dynamics of old-growth hemlock forests in central Bhutan are shaped by natural disturbances

Forest Ecosystems 2024年第4期11卷 434-447页

作者： Karma Tenzin Craig r.Nitschke Kathryn j.Allen raphael Trouve Thiet V.Nguyen Patrick j.Baker School of Agriculture Foodand Ecosystem SciencesUniversity of Melbourne500 Yarra BlvdRichmondVictoriaAustralia School of Geography Planningand Spatial SciencesUniversity of TasmaniaSandy BayTasmaniaAustralia Forest Science Institute of South Vietnam 1 Pham Van Hai StreetTan Binh DistrictHo Chi Minh CityViet Nam

Understanding how past disturbances have influenced the development of forests is critical for deciphering their current structure and composition and forecasting future *** this study,dendrochronological methods were applied to uncover the disturbance history of old-growth hemlock-dominated forests in central *** of tree-ring samples from two old-growth hemlock stands,located in two different topographic settings,identified the importance of gap-phase dynamics in facilitating recruitment and growth releases and producing complex,multi-aged structure s over *** site showed evidence of a near stand-replacing disturbance in the late 1700s,while the other showed no evide nce of high-severity disturbance at any time over the last 400 *** both sites low-to medium-severity disturbances,some of which appear to be associated with cyclones originating in the Bay of Bengal,dominated the disturbance *** hemlock stands exhibited a significant positive association between cyclone occurrence and growth release events and between recruitment pulses and growth release *** 1800 to 1970 there was an increase in recruitment of angiosperm tree species at most sites and a corresponding decline in conifer *** the past 50 years there has been little new recruitment;this may be due to light limitation in the understory from shade-tolerant angiosperms and bamboo in the lower strata of these *** variations in disturbance dynamics and recruitment were observed across the study sites,suggesting that other factors,such as topography and climate,may be influencing long-term stand development *** study highlights the complex interplay between historical disturbance regimes and tree recruitment in shaping the age and size structures of old-growth hemlock forests in central *** also provides new insights into the dynamics of these forests that can be used to support effective forest conservation and management i

关键词： Forest structure Hemlock forest Himalaya Natural disturbance

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Influence of the zigzag fins and inlet arrangements on the cooling proficiency of the mini-channel heat sink

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Propulsion and Power research 2024年第2期13卷 194-206页

作者： A.Torbatinezhad Y.Pahamli M.j.Hosseini r.Bahrampoury School of Mechanical Engineering Babol University of TechnologyBabolIran Department of Mechanical Engineering Semnan UniversitySemnanIran Department of Mechanical Engineering Faculty of EngineeringGolestan UniversityGorganIran Department of Mechanical Engineering K.N.Toosi University of TechnologyTehranIran

Mini-channel heatsinks are one of the most effective thermal management methods for high heatﬂux devices due to the high performance of convective heat *** recent years,various techniques have been innovated to improve the thermal proﬁciency of the mini-channel *** of these are taking advantage ofﬁns’structural designs and ar-rangements of inlets and *** zigzagﬁns and channels were considered in the previous works in heatsinks,and researchers analyzed their cooling enhancement ***,in the present work,a combined cooling technique,considering new-type zigzagﬁns’geometrical parameters(arrangement,length,and height)causes turbulenceﬂow and higher convective heat transfer along with different positionings ofﬂow inlet and outlets resulting in superior temper-ature uniformity,is proposed to evaluate their impacts on the cooling proﬁciency of the heat sink versus different reynolds *** assess the thermal and hydraulic performance of the proposed heatsink,different parameters,including temperature contours,Nusselt numbers,thermal resistance,and entropy generation are *** a result,it is observed that in the case demonstrating the best thermal performance,the Nusselt number,pressure drop,thermal resistance,and entropy generation are respectively 37.13,4586.46 Pa,0.000078 m^(2)·K/W,and 0.1078 W/K in the best *** well,it is found that by changing the arrangements of inlets and outlets,the Nusselt number,and thermal resistance are improved by 12%and 13%,***,the proposed mini-channel heat sink could be used as a high-performance thermal management system for electronic devices in different industries,including energy,solar,and medical sectors.

关键词： Thermal management Heat transfer enhancement Mini-channel heatsink Zigzagﬁn Entropy generation Electronic cooling

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Management of monogenic diabetes in pregnancy:A narrative review

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World journal of Diabetes 2024年第1期15卷 15-23页

作者： Mohammad Sadiq jeeyavudeen Sarah r Murray Mark W j Strachan Metabolic Unit Western General HospitalEdinburgh EH42XUUnited Kingdom MrC Centre for reproductive Health University of Edinburgh Queen’s Medical Research InstituteEdinburgh EH164TJUnited Kingdom

Pregnancy in women with monogenic diabetes is potentially complex,with significant implications for both maternal and fetal *** these,maturity-onset diabetes of the young(MODY)stands out as a prevalent monogenic diabetes subtype frequently encountered in clinical *** subtype of MODY requires a distinct approach tailored to the pregnancy,diverging from management strategies in non-pregnant *** MODY(GCK-MODY)typically does not require treatment outside of pregnancy,but special considerations arise when a woman with GCK-MODY becomes *** glycemic targets in GCK-MODY pregnancies are not exclusively dictated by the maternal/paternal MODY genotype but are also influenced by the genotype of the developing *** pregnancy,the choice between sulfonylurea or insulin for treating hepatocyte nuclear factor 1-alpha(HNF1A)-MODY and HNF4A-MODY depends on the mother’s specific circumstances and the available *** of other rarer MODY subtypes is individu-alized,with decisions made on a case-by-case ***,a collaborative approach involving expert diabetes and obstetric teams is crucial for the compre-hensive management of MODY pregnancies.

关键词： Diabetes Pregnancy Maturity-onset diabetes of the young Insulin Sulphonylurea Glucokinase Hepatocyte nuclear factor 1-alpha,hepatocyte nuclear factor 1-beta,and hepatocyte nuclear factor 4-alpha

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Sustainable plasticulture in Chinese agriculture: a review of challenges and routes to achieving long-term food and ecosecurity

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 155-168页

作者： Samuel j.CUSWOrTH William j.DAVIES Martin r.MCAINSH Carly j.STEVENS Weilu WANG Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK The Institutes of Agricultural Science and Technology Development Yangzhou UniversityYangzhou 225009China

Plastic pollution is global concern, affecting most aspects of global food production systems. Plasticulture, a practice used in agriculture to improve crop quality and quantity, among other factors, is a significant source of plastic pollution. This review examines the extent of plasticulture in China, the implications of the practice across decades of use and the legislative instruments used to resolve those issues. It briefly assesses the effectiveness of these policies and proposes possible future innovations to promote increases in long-term food and eco-security, where sustainable plasticulture is a key agent for change. While plasticulture has increased agricultural productivity in growth-limiting conditions, plastic pollution in agricultural soils has become acute in China. Consequently, plastic pollution is having deleterious effects on soil health and in turn, crop productivity in China. Plastic pollution in agriculture is a multifaceted issue and so proposed solutions should be informed by this complexity. Current measures do not reflect a holistic approach to solving this socioecological challenge and adopt a top-down approach, with little or no supportive mechanisms. Future recommendations need to consider the particular set of conditions that influence the production, use and end-of-life management of agriplastics,specific to the environmental, economic and social conditions in each location.

关键词： Circular plastics economy crop production food security plastic pollution sustainable plasticulture

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Inflow and outflow permeability tests in a very soft clay under low stresses

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journal of rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： j.W.S.Vargas F.A.B.Danziger F.r.Lopes T.Lunne Federal University of rio de janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the BAT probe at SarapuíII soft clay test site are presented.A description of the BAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for SarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test Soft clay BAT probe Inflow and outflow tests

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resolution and alteration with ample exceptional divisor

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Science China Mathematics 2024年

作者： jános Kollár jakub Witaszek Department of Mathematics Princeton University

In this note, we construct resolutions or regular alterations admitting an ample exceptional divisor,assuming the existence of projective resolutions or regular alterations. In particular, this implies the existence o...

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A review of public health guidelines for postpartum physical activity and sedentary behavior from around the world

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journal of Sport and Health Science 2024年第4期13卷 472-483,F0003页

作者： Kelly r.Evenson Wendy j.Brown Alison K.Brinson Emily Budzynski-Seymour Melanie Hayman Department of Epidemiology Gillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillNC 27599-8050USA Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia Department of Anthropology University of North Carolina at Chapel HillChapel HillNC 27599-3115USA Carolina Population Center University of North Carolina at Chapel HillChapel HillNC 27599-8120USA Faculty of Sport Health and Social SciencesSolent UniversitySouthamptonSO140YNUK Appleton Institute School of HealthMedical and Applied SciencesCentral Queensland UniversityRockhamptonQLD 4701Australia

Background:The period following pregnancy is a critical time window when future habits with respect to physical activity(PA) and sedentary behavior(SB) are established;therefore,it warrants *** purpose of this scoping review was to summarize public health-oriented country-specific postpartum PA and SB guidelines ***:To identity guidelines published since 2010,we performed a(a) systematic search of 4 databases(CINAHL,Global Health,PubMed,and SPOrTDiscus),(b) structured repeatable web-based search separately for 194 countries,and(c) separate web-based *** the most recent guideline was included for each ***:We identified 22 countries with public health-oriented postpartum guidelines for PA and 11 countries with SB *** continents with guidelines included Europe(n=12),Asia(n=5),Oceania(n=2),Africa(n=1),North America(n=1),and South America(n=1).The most common benefits recorded for PA included weight control/management(n=10),reducing the risk of postpartum depression or depressive symptoms(n=9),and improving mood/well-being(n=8).Postpartum guidelines specified exercises to engage in,including pelvic floor exercises(n=17);muscle strengthening,weight training,or resistance exercises(n=13);aerobics/general aerobic activity(n=13);walking(n=11);cycling(n=9);and swimming(n=9).Eleven guidelines remarked on the interaction between PA and breastfeeding;several guidelines stated that PA did not impact breast milk quantity(n=7),breast milk quality(n=6),or infant growth(n=3).For SB,suggestions included limiting long-term sitting and interrupting sitting with ***:Country-specific postpartum guidelines for PA and SB can help promote healthy behaviors using a culturally appropriate context while providing specific guidance to public health practitioners.

关键词： Breastfeeding Caesarean section Guidelines Postnatal recommendations

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Adaptation in brain structure and respiratory and olfactory structures across environmental gradients in African and North American muroid rodents

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Integrative Zoology 2024年第1期19卷 165-181页

作者： Peter j.TAYLOr Aluwani NENGOVHELA Christiane DENYS Graham r.SCOTT Catherine M.IVY Department of Zoology School of Natural and Mathematical SciencesUniversity of VendaThohoyandouSouth Africa Afromontane Unit Department of Zoology and EntomologyUniversity of the Free StatePhuthaditjhabaSouth Africa Department of Mammalogy National MuseumBloemfonteinSouth Africa Institut de Systématique EvolutionBiodiversité(ISYEB)Muséum National d’Histoire NaturelleCNRSSorbonne UniversitéEPHEUniversitéDes AntillesParisFrance Department of Biology McMaster UniversityHamiltonOntarioCanada Guglielmo and Shoemaker Labs Advanced Facility for Avian ResearchUniversity of Western OntarioLondonOntarioCanada

Morphometric studies of 3D micro CT-scanned images can provide insights into the evolution of the brain and sensory structures but such data are still scarce for the most diverse mammalian order of *** reviewed and new data,we tested for convergence to extreme aridity and high elevation in the sensory and brain morphology of rodents,from morphometric data from micro-CT X-ray scans of 174 crania of 16 species of three distantly re-lated African murid(soft-furred mice,Praomyini,laminate-toothed rats,Otomyini,and gerbils,Gerbillinae)clades and one North American cricetid(deer mice and white-footed mice,Peromyscus)*** studies demon-strated convergent evolution acting on the oval window area of the cochlea(enlarged in extremely arid-adapted species of Otomyini and Gerbillinae)and on endocranial volume(reduced in high elevation taxa of Otomyini and Peromyscus).However,contrary to our predictions,we did notfind evidence of convergence in brain struc-ture to aridity,or in the olfactory/respiratory system(turbinate bones)to high *** structure differed,particularly in the petrosal lobules of the cerebellum and the olfactory bulbs,between Otomyini and Gerbillinae,with extreme arid-adapted species in each clade being highly divergent(not convergent)from other species in the same *** observed greater“packing”of the maxillary turbinate bones,which have important respiratory functions,in Peromyscus mice from high and low elevations compared to the high-elevation African Praomyini,but more complex patterns within Peromyscus,probably related to trade-offs in respiratory physiology and heat exchange in the nasal epithelium associated with high-elevation adaptation.

关键词： 3D morphometrics Africa brain size North America rodentia sensory evolution

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Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

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First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of rE_(2)rh_(3)Ge(rE=Pr,Sm)

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journal of rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier r.Masrour M.Hamedoun j.Kharbach A.rezzouk A.Hourmatallah N.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys rE_(2)rh_(3)Ge(rE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** Debye temperature increases with increasing pressure and decreases with decreasing ***,the Debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： Magnetic metals Functional density theory Density of states Magnetic moment Optical and thermodynamic properties rare earths

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