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Response of.Seasonal Vegetation Dynamics to Climatic Constraints in Northeastern Burundi

Journal of.Geoscience and Environment Protection 2020年第9期8卷 151-181页

作者： Pacif.que Batungwanayo Marnik Vanclooster alan f. koropitan Departement of.Mathematics Institute of Applied Pedagogy University of Burundi Bujumbura Burundi Research Center f.r Mathematical and Physical Sciences Doctoral School University of Burundi Bujumbura Burundi Earth and Lif. Institute Université Catholique de Louvain Louvain-la-Neuve Belgium f.culty of.f.sheries and Marine Sciences IPB University Bogor Indonesia

The climate crises in East Af.ica (EA), particularly in Burundi, have af.ected vegetation which, in turn, plays a key role in the climate system by modif.ing the terrestrial water and energy balance. Consequently, it is vital to understand vegetation dynamics and its response to current and projected climate conditions to support the design of.climate resilient land management strategies. The objective of.this study was to study the dynamics of.vegetation cover over the Northeastern Burundi (NEB) in response to climatic constraints. The methodology used consisted of.the interpretation of.satellite images along with the analysis of.data collected through rain-gauge stations. The data sets used include time series composite moderate resolution imaging spectroradiometer (MODIS) normalized dif.erence vegetation index (NDVI) data collected between f.bruary 2000 and December 2017;long term (1986-2017) rainf.ll data acquired f.om two meteorological stations throughout the Northeastern provinces in Burundi and precipitation and mean temperature data (1986-2017) f.om Climate Hazards Group Inf.aRed Precipitation with Station data (CHIRPS) and ERA5 Daily aggregates f.r the study area. The study provides an assessment of.the vegetation trends in NEB using the NDVI time series. In addition, regression analysis is applied to assess the relations between NDVI and precipitation, air temperature, potential evapotranspiration, as well as with growing season characteristics (onset, cessation, and length). Results show that the rate in vegetation productivity is persistently gradual between 2000 and 2011 despite f.uctuations f.om the mean position, f.llowed by a lower growth rate over the period 2011-2017. There has been trend variation in precipitation, neither the temperature was constant. The temperature over the region has increased while the precipitation has decreased. The onset of.the growing season and air temperature also show a signif.cant inf.uence on seasonal vegetation dynamics in the region. Drought-induced plant stres

关键词： Rainf.ll Variability Onset Dry Spell NDVI Remote Sensing Northeastern Burundi

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Bulking Up the Bay-Position Substituents Enables Enhanced Selectivity of.Cs‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina f.f.rac alan J.Lough Timothy P.Bender Department of.Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of.Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of.Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of.Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of.subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of.f.nctional macrocycles.Easy,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Ncp)s,are desirable f.r this purpose yet synthetically challenging due to random mixtures of.Cs-,C3v-,and,in some cases,C1-symmetric compounds that f.rm during traditional statistical mixed cyclotrimerizations.Herein,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity f.r the targeted Cs-symmetric hybrid and complete suppression of.sterically crowded macrocyclic byproducts.This process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of.bay-position phenylated Ph2-(Rp)8Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or f.in their peripheral isoindole rings.Reaction selectivity ranged between 59 and 72%with remarkable yields,signif.cantly higher than that of.conventional mixed cyclotrimerizations.These f.ndings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle f.rmation.Additionally,the incorporation of.unf.sed phenyl groups and halogen atoms into the hybrid f.amework resulted in f.ne-tuned optical,structural,electronic,and electrochemical properties.This straightf.rward approach achieved improved selectivity and controlled narrowing of.the product distribution,af.ording the ef.icient synthesis of.structurally sophisticated Bsub(Pc_(2)-Nc_(1))hybrids.This then expands the library of.3-dimensionalπ-extended macrocycles f.r use in a range of.applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

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Quantum-mechanical ef.ects in photoluminescence f.om thin crystalline gold f.lms

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Light(Science & Applications) 2024年第4期13卷 783-794页

作者： alan R.Bowman Alvaro Rodríguez Echarri f.temeh Kiani f.dil Iyikanat Ted V.Tsoulos Joel D.Cox Ravishankar Sundararaman f.Javier García de Abajo Giulia Tagliabue Laboratory of.Nanoscience f.r Energy Technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICf.–Institut de Ciencies f.toniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. MBI–Max-Born-Institut BerlinGermany. POLIMA–Center f.r Polariton-driven Light–Matter Interactions University of Southern DenmarkOdense MDenmark. Danish Institute f.r Advanced Study University of Southern DenmarkOdense MDenmark. Department of.Materials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. Department of.Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Avancats BarcelonaSpain

Luminescence constitutes a unique source of.insight into hot carrier processes in metals,including those in plasmonic nanostructures used f.r sensing and energy applications.However,being weak in nature,metal luminescence remains poorly understood,its microscopic origin strongly debated,and its potential f.r unraveling nanoscale carrier dynamics largely unexploited.Here,we reveal quantum-mechanical ef.ects in the luminescence emanating f.om thin monocrystalline gold f.akes.Specif.cally,we present experimental evidence,supported by f.rst-principles simulations,to demonstrate its photoluminescence origin(i.e.,radiative emission f.om electron/hole recombination)when exciting in the interband regime.Our model allows us to identif. changes to the measured gold luminescence due to quantum-mechanical ef.ects as the gold f.lm thickness is reduced.Excitingly,such ef.ects are observable in the luminescence signal f.om f.akes up to 40 nm in thickness,associated with the out-of.plane discreteness of.the electronic band structure near the f.rmi level.We qualitatively reproduce the observations with f.rst-principles modeling,thus establishing a unif.ed description of.luminescence in gold monocrystalline f.akes and enabling its widespread application as a probe of.carrier dynamics and light-matter interactions in this material.Our study paves the way f.r f.ture explorations of.hot carriers and charge-transf.r dynamics in a multitude of.material systems.

关键词： luminescence quantum crystalline

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Soleus arthrogenic muscle inhibition f.llowing acute lateral ankle sprain correlates with symptoms and ankle disability but not with postural control

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Journal of.Sport and Health Science 2024年第4期13卷 559-568,F0003页

作者： Kyung-Min Kim Joo-Sung Kim alan R.Needle Department of.Sport Science Sungkyunkwan UniversitySuwon-si 16419Republic of Korea Department of.Health and Human Perf.rmance Texas State UniversitySan MarcosTX 78666USA Department of.Public Health&Exercise Science Appalachian State UniversityBooneNC 28608USA Department of.Rehabilitation Science Appalachian State UniversityBooneNC 28608USA

Background:Acute lateral ankle sprains(ALAS)are associated with long-term impairments and instability tied to altered neural excitability.Arthrogenic muscle inhibition(AMI)has been observed in this population;however,relationships with injury-related impairments are unclear,potentially due to the resting,prone position in which AMI is typically measured.Assessing AMI during bipedal stance may provide a better understanding of.this relationship.Methods:AMI was assessed in 38 young adults(19 ALAS within 72 h of.injury:10 males,21.4±2.7 years;19 healthy controls:10 males,21.9±2.2 years;mean±SD)using the Hof.mann ref.ex(H-ref.ex)during bipedal stance.Electrical stimulation was administered to identif. the _(max)imal H-ref.ex(H_(max))and _(max)imal motor response(M_(max))f.om the soleus,f.bularis longus,and tibialis anterior muscles.The primary outcome measure was the H_(max)/M_(max) ratio.Secondary outcomes included acute symptoms(pain and swelling),postural control during bipedal stance,and self.reported f.nction.Results:No signif.cant group-by-limb interactions were observed f.r any muscle.However,a signif.cant group main ef.ect was observed in the soleus muscle(f.1,35)=6.82,p=0.013),indicating signif.cantly lower H_(max)/M_(max) ratios f.llowing ALAS(0.38±0.20)compared to healthy controls(0.53±0.16).f.rthermore,lower H_(max)/M_(max) ratios in the soleus signif.cantly correlated with acute symptoms and self.reported f.nction but not with postural control.Conclusion:This study supports previous evidence of.AMI in patients with ALAS,providing insight into neurophysiologic impacts of.musculoskeletal injury.Our results suggest that assessing AMI in a standing position f.llowing acute injury may provide valuable insight into how AMI develops and guide potential therapeutic options to curb and of.set the f.rmation of.joint instability.

关键词： Acute injuries Balance Hof.mann ref.ex Neural excitability Patient-reported outcomes

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Perceptual lateralization of.vocal stimuli in goats

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Current Zoology 2019年第1期65卷 67-74页

作者： Luigi Baciadonna Christian Nawroth Elodie f. Brief.r alan G. McELLiGOTT Biological and Experimental Psychology School of Biological and Chemical Sciences Queen Mary University of London Mile End Road London E1 4NS UK Institute of.Behavioural Physiology Leibniz Institute for Farm Animal Biology Dummerstorf Germany Institute of.Agricultural Sciences ETH Zurich Universitatstrasse 2 8092 Zurich Switzerland Department of.Lif. Sciences University of Roehampton London SW15 4JD UK

f.nctional asymmetries, f.r example, the pref.rential involvement of.1 brain hemisphere to process stimuli, may increase brain ef.iciency and the capacity to carry out tasks simultaneously. We investigated which hemisphere was primarily invoIved in processing acoustic stimuli in goats using a headorienting paradigm. Three playbacks using goat vocalizations recorded in dif.erent contexts: f.od anticipation (positive), isolation (negative), f.od f.ustration (negative), as well as 1 playback involving dog barks (negative) were presented on the lef. and right sides of.the test subjects simultaneously. The head-orienting response (lef. or right) and latency to resume f.eding were recorded. The direction of.the head-orienting response did not dif.er between the various playbacks. However, when the head-orienting response was tested against chanee level, goats showed a right bias regardless of.the stimuli presented. Goats responded more to dog barks than to f.od f.ustration calls, whereas responses to f.od anticipation and isolation calls were intermediate. In addition, the latency to resume f.eding, an indicator of.f.ar reaction, was not af.ected by the kind of.vocalization presented. These results provide evidence f.r asymmetries in goat vocal perceptio n of.emotional-li nked con specif.c and heterospecif.c calls. They also suggest involvement of.the lef. brain hemisphere f.r processing acoustic stimuli, which might have been perceived as f.miliar and non -threate ning.

关键词： auditory processing brain asymmetry emotions lateralization social cognition vocal communication

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Sexual selection af.ects the sizes of.the mammalian prostate gland and seminal vesicles

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Current Zoology 2009年第1期55卷 1-8页

作者： Matthew J. ANDERSON alan f. DIXSON Conservation and Research f.r Endangered Species Zoological Society of San Diego School of.Biological Sciences Victoria University of Wellington

The accessory reproductive glands of.male mammals contribute the bulk of.the secretions in which spermatozoa are transported to the f.male tract during copulation. Despite their morphological diversity,and the chemical complexity of.their products,little is known about the possible ef.ects of.sexual selection upon these glands in mammals. Here we consider the seminal vesicles and prostate glands in a sample of.89 species and 60 genera representing 8 Orders of.mammals. The sizes of.the accessory glands are analysed in relation to body weight and testes weight. Both the seminal vesicles size and prostate size (corrected f.r body weight) correlate positively with relative testes size in this sample; this f.nding remains highly signif.cant af.er application of.procedures to correct f.r possible phylogenetic biases in the data set. The accessory reproductive glands are also signif.cantly larger in those mammals which have large relative testes sizes,and in which the likelihood of.sperm competition is greatest. These results support the hypothesis that sexual selection has played an important role in the evolution of.the mammalian prostate gland and seminal

关键词：哺乳动物生殖腺精囊睾丸

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Phase constitution of.the noble metal thin-f.lm complex solid solution system Ag-Ir-Pd-Pt-Ru in dependence of.elemental compositions and annealing temperatures

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Nano Research 2022年第6期15卷 4827-4836页

作者： Bin Xiao Xiao Wang alan Savan Alf.ed Ludwig Materials Discovery and Interf.ces Institute for MaterialsRuhr University Bochum44780 BochumGermany Zentrum f.r Grenzf.ächendominierte Höchstleistungswerkstof.e(ZGH) Ruhr University Bochum44780 BochumGermany

Multiple-principal element alloys hold great promise f.r multif.nctional material discovery(e.g.,f.r novel electrocatalysts based on complex solid solutions)in a virtually unlimited compositional space.Here,the phase constitution of.the noble metal system Ag-Ir-Pd-Pt-Ru was investigated over a large compositional range in the quinary composition space and f.r dif.erent annealing temperatures f.om 600 to 900°C using thin-f.lm materials libraries.Composition-dependent X-ray dif.raction mapping of.the asdeposited thin-f.lm materials library indicates dif.erent phases being present across the composition space(f.ce-centered cubic(f.c),hexagonal close packed(hcp)and mixed f.c+hcp),which are strongly dependent on the Ru content.In general,low Ru contents promote the f.c phase,whereas high Ru contents f.vor the f.rmation of.an hcp solid-solution phase.f.rthermore,a temperature-induced phase transf.rmation study was carried out f.r a selected measurement area of.f.c-Ag_(5)Ir_(8)Pd_(56)Pt_(8)Ru_(23).With increasing temperature,the initial f.c phase transf.rms to an intermediate C14-type Laves phase at 360°C,and then to hcp when the temperature reaches 510°C.The f.rmation and disappearance of.the hexagonal Laves phase,which covers a wide temperature range,plays a crucial role of.bridging the f.c to hcp phase transition.The obtained composition,phase and temperature data are transf.rmed into phase maps which could be used to guide theoretical studies and lay a basis f.r tuning the f.nctional properties of.these materials.

关键词： noble metal high-entropy alloys phase transf.rmation combinatorial synthesis and high-throughput characterization

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基于回授式健康教育的延续护理方案对内窥镜下声带息肉摘除术患者嗓音康复的影响

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黑龙江医学 2024年第2期48卷 205-207页

作者：江阿兰李灵郑星福建医科大学附属第一医院耳鼻咽喉头颈外科福建福州350004

目的:探讨基于回授式健康教育的延续护理方案对内窥镜下声带息肉摘除术患者嗓音康复的影响,为临床护理干预提供依据。方法:选取2021年1—12月福建医科大学附属第一医院收治的64例行内窥镜下声带息肉摘除术的患者作为研究对象,采用随机... 详细信息

目的:探讨基于回授式健康教育的延续护理方案对内窥镜下声带息肉摘除术患者嗓音康复的影响,为临床护理干预提供依据。方法:选取2021年1—12月福建医科大学附属第一医院收治的64例行内窥镜下声带息肉摘除术的患者作为研究对象,采用随机数表法分为对照组与回授组,每组各32例。对照组接受常规院外随访,回授组接受基于回授式健康教育的延续护理方案,两组患者均干预1个月。比较两组患者干预前后嗓音障碍程度[中文版嗓音障碍指数(VHI)量表评分]、嗓音声学参数[基频微扰(Jitter)、振幅微扰(Shimmer)、噪谐比(NHR)、最高基频(f.igh)、最长发声时间(MPT)]情况。结果:干预1个月,回授组患者VHI量表中f.P、E 3个维度评分及T评分均明显低于对照组患者,差异有统计学意义(t=4.567、8.468、6.697、6.577,P<0.05)。干预1个月,回授组患者Jitter、Shimmer、NHR及嗓音障碍严重指数(DSI)显著低于对照组患者,MPT显著长于对照组患者,差异有统计学意义(t=10.219、4.243、5.657、3.628、6.754,P<0.05)。结论:构建并实施基于回授式健康教育的延续护理方案,有利于促进内窥镜下声带息肉摘除术患者的声带功能恢复,提高嗓音质量。

关键词：内窥镜下声带息肉摘除术回授式健康教育延续护理嗓音康复

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Cognitive screening f.r adult psychiatric outpatients: Comparison of.the Cognivue® to the Montreal Cognitive Assessment

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World Journal of.Psychiatry 2021年第7期11卷 265-270页

作者： Amanda f.Rose alan f.Gilbertson Constance Cottrell Rajesh R Tampi Department of.Psychiatry and Behavioral Sciences Cleveland Clinic Akron GeneralAkronOH 44307United States Of.ice of.Nursing Research and Innovation Cleveland ClinicClevelandOH 44106United States

In this editorial we comment on the article by Cahn-Hidalgo D published in a recent issue of.the World Journal of.Psychiatry 2020;10(1);1-11.We f.cus on the importance of.utilizing psychometrically valid cognitive screening tools when assessing f.r cognitive decline in older adults in a psychiatric outpatient setting.We compared the use of.Cognivue®to use of.the montreal cognitive assessment(MoCA)as a cognitive screening tool.A total of.58 patients aged 55 and over participated in this comparison study.Patients completed cognitive screening on Cognivue®,a new f.od and Drug Administration-cleared computer screening device,and the MoCA.The results of.patient perf.rmance using these two instruments were analyzed.Sixteen(28%)patients screened negative f.r cognitive impairment on both assessments.f.rty-two(72%)patients screened positive on one or both of.the assessments.There was 43%agreement between Cognivue®and the MoCA in identif.ing patients with cognitive impairment,and individual subtests were weakly correlated.The MoCA was determined to be the pref.rred instrument due to its high sensitivity and specif.city(100%and 87%,respectively)when screening f.r cognitive impairment.We propose that the use of.Cognivue®cognitive screening tool be closely reviewed until more research proves that the test meets the standards f.r reliability and validity.It is important f.r clinicians to remember that screeners should not be used to diagnosis patients with neurocognitive disorders;instead,they should be used to determine whether f.rther evaluation is warranted.Additionally,misdiagnosing of.neurocognitive disorders can pose unnecessary psychological and emotional harm to patients and their f.milies and also lead to incorrect treatment and undue healthcare costs.

关键词： Dementia Cognitive screening test Cognitive impairment Psychological assessment Neurocognitive disorder Geriatric psychiatry Cognitive decline

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f.st extended depth of.f.cus meta-optics f.r varif.cal f.nctionality

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Photonics Research 2022年第3期10卷 828-833页

作者： James E.M.Whitehead alan Zhan Shane Colburn Luocheng Huang Arka Majumdar Department of.Electrical and Computer Engineering University of WashingtonSeattleWashingtonD.C.98195USA Tunoptix SeattleWashingtonD.C.98195USA Department of.Physics University of WashingtonSeattleWashingtonD.C.98195USA

Extended depth of.f.cus(EDOf.optics can enable lower complexity optical imaging systems when compared to active f.cusing solutions.With existing EDOf.optics,however,it is dif.icult to achieve high resolution and high collection ef.iciency simultaneously.The subwavelength spacing of.scatterers in a meta-optic enables the engineering of.very steep phase gradients;thus,meta-optics can achieve both a large physical aperture and a high numerical aperture.Here,we demonstrate a f.st(f.1.75)EDOf.meta-optic operating at visible wavelengths,with an aperture of.2 mm and f.cal range f.om 3.5 mm to 14.5 mm(286 diopters to 69 diopters),which is a 250×elongation of.the depth of.f.cus relative to a standard lens.Depth-independent perf.rmance is shown by imaging at a range of.f.nite conjugates,with a minimum spatial resolution of.9.84μm(50.8 cycles/mm).We also demonstrate operation of.a directly integrated EDOf.meta-optic camera module to evaluate imaging at multiple object distances,a f.nctionality which would otherwise require a varif.cal lens.

关键词： optics enable otherwise

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