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Population dynamics of three lizard species from the genus Sceloporus:short-term changes in demographic parameters

Integrative zoology 2019年第6期14卷 542-560页

作者： Selene VARGAS-GARCÍA Víctor ARGAEz Israel SOLANO-zAVALETA j.jaime zúñiga-vega Graduate Program in Biological Sciences National Autonomous University of MexicoUniversity CityMexico CityMéxico Department of Ecology and Natural Resources Faculty of SciencesNational Autonomous University of MexicoUniversity CityMexico CityMéxico.

Most demographic studies focus on numerical changes that occur within populations across years.However,typically studies at an interannual scale do not provide information on the particular times of the year(particular months or seasons)when rates of survival,recruitment,or migration increase or decrease due to physiological,behavioral or ecological processes.These monthly or seasonal changes in demographic parameters may lead to substantial variations in population abundance.In this study,we collected capture-mark-recapture data on 3 species of lizards of the genus Sceloporus(Sceloporus torquatus,Sceloporus grammicus and Sceloporus megalepidurus)found in ecologically similar habitats to examine potential changes in demographic rates among 3 different climatic seasons:rainy,cold-dry and warm-dry seasons.We tested different hypotheses about the effect of these seasons on survival,recruitment of new adults,and temporary emigration.We found that during the season with severe thermal constraints,the cold-dry season,survival of S.torquatus decreased markedly.We also detected a considerable increase in the recruitment rate of S.grammicus during the rainy season,when these lizards are establishing territories and finding mates.In contrast,we found no evidence of intra-annual changes in the rate of temporary emigration.In addition,we calculated abundance and population growth rates for each species and for each season.Our study represents a significant contribution to the understanding of intra-annual demographic variation in lizards.

关键词： abundance recruitment Sceloporus lizards survival temporary emigration

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Cytomegalovirus Transverse Myelitis Secondary to Influenza Infection and Early Recovery:A Case Report

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Infectious Diseases & Immunity 2024年第1期4卷 41-42页

作者： jill S.Bhavsar Lekhini K.Fultariya Poojan j.Prajapati Archi K.Dhamelia jaime E.Campos Department of Infectious Disease Hialeah HospitalMiamiFL(affiliated with HerbertWertheim College of MedicineFlorida International University)33013USA

Immunosuppression can lead to opportunistic infections in a host.The evidence of viral infections causing immunosuppression in a host for a transient period is gaining attention.In order to prolong their stay in the human body,viruses affect the human immune systemin various ways.Common viral infections such as influenza can lead to transient lymphocytopenia,which lays the groundwork for more dangerous opportunistic infections.Cytomegalovirus(CMV)infection is a rare cause of inflammatory myelopathy.We present the case of a patient with an influenza infection who progressed to severe acute respiratory distress syndrome,methicillin-resistant Staphylococcus aureus necrotizing pneumonia,and idiopathic lymphocytopenia with a CD4 count of 61 perμL on arrival.After 2 weeks,the patient developed complete flaccid paralysis with sensory and autonomic dysfunction.Because his polymerase chain reaction results of cerebrospinal fluid and blood test were positive for CMV infection,he was treated with high doses of steroids and ganciclovir intravenously.Due to early diagnosis and intervention,the patient was able to recover in 2 months with only minimal residual weakness.Thus,this case stresses on the importance of looking out for opportunistic infections in patients affected by severe viral infections for their early recovery.

关键词： Influenza,Human Lymphocytopenia Transverse myelitis Case report

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Unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neuropathology and behavioral deficits in parkinsonian rats withα-synucleinopathy

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Neural Regeneration Research 2024年第9期19卷 2057-2067页

作者： Bismark Gatica-Garcia Michael j.Bannon Irma Alicia Martínez-Dávila Luis O.Soto-Rojas David Reyes-Corona Lourdes Escobedo Minerva Maldonado-Berny ME Gutierrez-Castillo Armando j.Espadas-Alvarez Manuel A.Fernandez-Parrilla juan U.Mascotte-Cruz CP Rodríguez-Oviedo Irais E.Valenzuela-Arzeta Claudia Luna-Herrera Francisco E.Lopez-Salas jaime Santoyo-Salazar Daniel Martinez-Fong Departamento de Fisiología Biofísica y NeurocienciasCentro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Department of Pharmacology Wayne State University School of MedicineDetroitMIUSA Laboratorio de Patogénesis Molecular Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Red de Medicina para la Educación y Desarrollo y la Investigación Científica de Iztacala(Red MEDICI) Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Nanoparticle Therapy Institute AguascalientesMéxico Departamento de Biociencias e Ingeniería Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y DesarrolloInstituto Politécnico NacionalCiudad de MéxicoMéxico Escuela Nacional de Medicina y Homeopatía Instituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Fisiología Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Biología Molecular y Biotecnología Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico Departamento de Física Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Programa de Nanociencias y Nanotecnología Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico

Parkinsonism by unilateral,intranigralβ-sitosterolβ-D-glucoside administration in rats is distinguished in that theα-synuclein insult begins unilaterally but spreads bilaterally and increases in severity over time,thus replicating several clinical features of Parkinson’s disease,a typicalα-synucleinopathy.As Nurr1 repressesα-synuclein,we evaluated whether unilateral transfected of rNurr1-V5 transgene via neurotensin-polyplex to the substantia nigra on day 30 after unilateralβ-sitosterolβ-D-glucoside lesion could affect bilateral neuropathology and sensorimotor deficits on day 30 post-transfection.This study found that rNurr1-V5 expression but not that of the green fluorescent protein(the negative control)reducedβ-sitosterolβ-D-glucoside-induced neuropathology.Accordingly,a bilateral increase in tyrosine hydroxylase-positive cells and arborization occurred in the substantia nigra and increased tyrosine hydroxylase-positive ramifications in the striatum.In addition,tyrosine hydroxylase-positive cells displayed less senescence markerβ-galactosidase and more neuron-cytoskeleton markerβIII-tubulin and brain-derived neurotrophic factor.A significant decrease in activated microglia(positive to ionized calcium-binding adaptor molecule 1)and neurotoxic astrocytes(positive to glial fibrillary acidic protein and complement component 3)and increased neurotrophic astrocytes(positive to glial fibrillary acidic protein and S100 calcium-binding protein A10)also occurred in the substantia nigra.These effects followed the bilateral reduction inα-synuclein aggregates in the nigrostriatal system,improving sensorimotor behavior.Our results show that unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neurodegeneration(senescence and loss of neuron-cytoskeleton and tyrosine hydroxylase-positive cells),neuroinflammation(activated microglia,neurotoxic astrocytes),α-synuclein aggregation,and sensorimotor deficits.Increased neurotrophic astrocytes and brain-derived neurotrophic factor can mediate t

关键词： A1 astrocytes A2 astrocytes gene therapy microglia motor deficits nanoparticles neurodegeneration neuroinflammation senescence α-synuclein aggregates

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3D printing of ABS Nanocomposites.Comparison of processing and effects of multi-wall and single-wall carbon nanotubes on thermal,mechanical and electrical properties

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journal of Materials Science & Technology 2022年第26期121卷 52-66页

作者： Sithiprumnea Dul Brenda j.Alonso Gutierrez Alessandro Pegoretti jaime Alvarez-Quintana Luca Fambri Department of Industrial Engineering and INSTM Research Unit University of TrentoTrento 38123Italy Centro de Investigación en Materiales Avanzados S.C.Unidad MonterreyApodaca 66600Mexico Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo LeónAvenida Universidad s/nCiudad UniversitariaSan Nicolás de los Garza 66451México

The following paper reports on a comparative study of the effects of two types of carbon nanotubes,namely multiwall(MWCNT)and single-wall(SWCNT)carbon nanotube,on the properties of 3D-printed parts produced with acrylonitrile-butadiene-styrene(ABS)nanocomposites with various CNT loadings of5-10 wt.%.Quasi-static tensile properties and Vicat softening temperature of 3D-printed parts were enhanced with the increasing CNT content.The highest enhancement in tensile properties was observed for the ABS/CNT nanocomposites at 10 wt.%filler loading.3D-printed ABS/SWCNT composites showed higher tensile modulus,better creep stability and higher Vicat temperature.However,the strength of ABS/SWCNT 3D samples is relatively lower than that of ABS/MWCNT.In addition,3D-printed parts exhibited anisotropic electrical conductive behaviour,which has a conductivity of through-layer of about2-3 orders of magnitude higher than cross-layer.The highest conductivity of 3D-printed samples reached25.2 S/m,and 9.3 S/m for ABS/MWCNT and ABS/SWCNT composites at 10 wt.%,respectively.The results obtained,i.***.the successful fuse filament fabrication and the consequent electromechanical properties,confirm that these 3D printable nanocomposite could be properly utilized for the production,and application up to about 90°C,of thermoelectric devices and/or resistors for flexible circuits.

关键词： Fuse filament fabrication Conductive polymers Nanocomposites Mechanical properties Creep behavior Resistivity

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Genome and clonal hematopoiesis stability contrasts with immune,cfDNA,mitochondrial,and telomere length changes during short duration spaceflight

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Precision Clinical Medicine 2024年第1期7卷 1-13页

作者： j.Sebastian Garcia-Medina Karolina Sienkiewicz S.Anand Narayanan Eliah G.Overbey Kirill Grigorev Krista A.Ryon Marissa Burke jacqueline Proszynski Braden Tierney Caleb M.Schmidt Nuria Mencia-Trinchant Remi Klotz Veronica Ortiz jonathan Foox Christopher Chin Deena Najjar Irina Matei Irenaeus Chan Carlos Cruchaga Ashley Kleinman jangKeun Kim Alexander Lucaci Conor Loy Omary Mzava Iwijn De Vlaminck Anvita Singaraju Lynn E.Taylor julian C.Schmidt Michael A.Schmidt Kelly Blease juan Moreno Andrew Boddicker junhua zhao Bryan Lajoie Andrew Altomare Semyon Kruglyak Shawn Levy Min Yu Duane C.Hassane Susan M.Bailey Kelly Bolton jaime Mateus Christopher E.Mason Department of Physiology and Biophysics Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine Weill Cornell MedicineNew YorkNY 10021USA Department of Immunology Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA Department of Stem Cell Biology and Regenerative Medicine Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033USA Space Exploration Technologies Corporation HawthomeCA 90250USA Sovaris Aerospace BoulderCO 80302USA Advanced Pattern Analysis&Human Performance Group BoulderCO 80302USA Children's Cancer and Blood Foundation Laboratories Departments of Pediatrics and Cell and Developmental BiologyDrukier Institute for Children's HealthMeyer Cancer CenterWeill Cornell MedicineNew YorkNY 10021USA Meyer Cancer Center Weill Cornell MedicineNew YorkNY 10065USA Department of Nutrition and Integrative Physiology Florida State UniversityTallahasseeFL 32306USA Department of Systems Engineering Colorado State UniversityFort CollinsCO 80523USA Element Biosciences San DiegoCA 10055USA Department of Environmental and Radiological Health Sciences Colorado State UniversityFort CollinsCO 80523USA Cell and Molecular Biology Program Colorado State UniversityFort CollinsCO 80523USA BioAstra Inc New YorkNYUSA Washington University St Louis Oncology Division St.LouisMO 63100USA Meinig School of Biomedical Engineering Cornell UniversityIthacaNY 14853USA The Feil Family Brain and Mind Research Institute Weill Cornell MedicineNY 10021USA WorldQuant Initiative for Quantitative Prediction Weill Cornell MedicineNew YorkNY 10021USA

Background The Inspiration4(I4)mission,the first all-civilian orbital flight mission,investigated the physiological effects of short-duration spaceflight through a multi-omic approach.Despite advances,there remains much to learn about human adaptation to spaceflight's unique challenges,including microgravity,immune system perturbations,and radiation exposure.Methods To provide a detailed genetics analysis of the mission,we collected dried blood spots pre-,during,and post-flight for DNA extraction.Telomere length was measured by quantitative PCR,while whole genome and cfDNA sequencing provided insight into genomic stability and immune adaptations.A robust bioinformatic pipeline was used for data analysis,including variant calling to assess mutational burden.Result Telomere elongation occurred during spaceflight and shortened after return to Earth.Cell-free DNA analysis revealed increased immune cell signatures post-flight.No significant clonal hematopoiesis of indeterminate potential(CHIP)or whole-genome instability was observed.The long-term gene expression changes across immune cells suggested cellular adaptations to the space environment persisting months post-flight.Conclusion Our findings provide valuable insights into the physiological consequences of short-duration spaceflight,with telomere dynamics and immune cell gene expression adapting to spaceflight and persisting after return to Earth.CHIP sequencing data will serve as a reference point for studying the early development of CHIP in astronauts,an understudied phenomenon as previous studies have focused on career astronauts.This study will serve as a reference point for future commercial and non-commercial spaceflight,low Earth orbit(LEO)missions,and deep-space exploration.

关键词： genomes clonal hematopoiesis stability immune mitochondria ribosomes spaceflight

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Sleep disturbances and predictors of nondeployability among active-duty army soldiers: an odds ratio analysis of medical healthcare data from fiscal year 2018

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Military Medical Research 2020年第3期7卷 335-342页

作者： jaime K.Devine jacob Collen jake j.Choynowski Vincent Capaldi Institutes for Behavior Resources Operational Fatigue and Performance2104 Maryland AveBaltimoreMD 21218USA Pulmonary Critical Care and Sleep Medicine Walter Reed National Military Medical CenterBethesdaMD 20889USA Behavioral Biology Branch Center for Military Psychiatry and NeuroscienceWalter Reed Army Institute of ResearchSilver SpringMD 20910USA

Background:The impact of sleep disorders on active-duty soldiers’medical readiness is not currently quantified.Patient data generated at military treatment facilities can be accessed to create research reports and thus can be used to estimate the prevalence of sleep disturbances and the role of sleep on overall health in service members.The current study aimed to quantify sleep-related health issues and their impact on health and nondeployability through the analysis of U.S.military healthcare records from fiscal year 2018(FY2018).Methods:Medical diagnosis information and deployability profiles(e-Profiles)were queried for all active-duty U.S.Army patients with a concurrent sleep disorder diagnosis receiving medical care within FY2018.Nondeployability was predicted from medical reasons for having an e-Profile(categorized as sleep,behavioral health,musculoskeletal,cardiometabolic,injury,or accident)using binomial logistic regression.Sleep e-Profiles were investigated as a moderator between other e-Profile categories and nondeployability.Results:Out of 582,031 soldiers,48.4%(n=281,738)had a sleep-related diagnosis in their healthcare records,9.7%(n=56,247)of soldiers had e-Profiles,and 1.9%(n=10,885)had a sleep e-Profile.Soldiers with sleep e-Profiles were more likely to have had a motor vehicle accident(p OR(prevalence odds ratio)=4.7,95%CI 2.63–8.39,P≤0.001)or work/duty-related injury(p OR=1.6,95%CI 1.32–1.94,P≤0.001).The likelihood of nondeployability was greater in soldiers with a sleep e-Profile and a musculoskeletal e-Profile(p OR=4.25,95%CI 3.75–4.81,P≤0.001)or work/dutyrelated injury(p OR=2.62,95%CI 1.63–4.21,P≤0.001).Conclusion:Nearly half of soldiers had a sleep disorder or sleep-related medical diagnosis in 2018,but their sleep problems are largely not profiled as limitations to medical readiness.Musculoskeletal issues and physical injury predict nondeployability,and nondeployability is more likely to occur in soldiers who have sleep e-Profiles in addition to these issues.Addressing sleep problems may pre

关键词： Medical readiness Behavioral sleep medicine Deployability Healthcare records Military Big data Data mining

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Natural sediment at a dam and its inorganic materials as adsorbents of praseodymium(Pr(Ⅲ))

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International journal of Sediment Research 2023年第4期38卷 566-575页

作者： Melania jiménez-Reyes jaime jiménez-Becerril Marcos Solache-Ríos Perla Tatiana Almazán-Sánchez Departamento de Química Instituto Nacional de Investigaciones Nucleares Carretera México-Toluca S/N CONACy T-Instituto Nacional de Investigaciones Nucleares

The sediment deposited behind a dam(DS) and its inorganic materials(IM-DS) were characterized and used for the removal of praseodymium(Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. Kinetic data fit well to a pseudo second-order model, the equilibrium time for DS and IM-DS was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/DS(qe= 4.91 mg/g) than for Pr/IM-DS(qe= 3.01 mg/g) in these conditions. Pr/DS and Pr/IM-DS data isotherms were in agreement with the Langmuir-Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic(enthalpy change, ΔH0=-22.8 and-21.8 k j/mol for DS and IM-DS, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium(EDTA-Na2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the EDTA-Na2solution. The Pr2(EDTA)3(praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials(DS and IM-DS). Distribution coefficients(KD) depend upon praseodymium concentration,temperature, p H, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption.

关键词： Praseodymium Sediment Adsorption process parameters Desorption

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Diversity and host assemblage of avian haemosporidians in different terrestrial ecoregions of Peru

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Current zoology 2022年第1期68卷 27-40页

作者： Luz GARCIA-LONGORIA jaime MURIEL Sergio MAGALLANES zaira Hellen VILLA-GALARCE Leonila RICOPA Wilson Giancarlo INGA-DIAz Esteban FONG Daniel VECCO Cesar GUERRA-SALDANA Teresa SALAS-RENGIFO Wendy FLORES-SAAVEDRA Kathya ESPINOzA Carlos MENDOzA Blanca SALDANA Manuel GONzALEz-BLAzQUEz Henry GONzALES-PINEDO Charlene LUjAN-vega Carlos Alberto Del AGUILA Yessica VILCA-HERRERA Carlos Alberto PINEDA Carmen REATEGUI jorge Manuel CARDENAS-CALLIRGOS joseAlberto IANNACONE jorge Luis MENDOzA Ravinder NMSEHGAL Alfonso MARzAL Departamento de Anatomia Biologia Celular y ZoologiaUniversidad de ExtremaduraBadajoz E-506071Spain Molecular Ecology and Evolution Lab Department of BiologyLund UniversitySolvegatan 37SE-22362 LundSweden Instituto Pirenaico de Ecologıa-IPE(CSIC) Avda.Nuestra Senora de la Victoria 16Jaca 22700Spain DIRESA Direccion Regional de SaludLoreto 16001Peru Departamento Academico de Microbiologia y Parasitologia.Facultad de Ciencias Biologicas Universidad Nacional de la Amazonia PeruanaIquitos 16001Peru Facultad de Ciencias Agropecuarias Universidad Alas PeruanasLima 15823Peru EverGreen Institute-San Rafael Distrito de IndianaLoreto 16200Peru Observatorio de Aves Loreto(LBO) Distrito de San JuanLoreto 16008Peru Centro Urku de Estudios Amazonicos Tarapoto 22200Peru Servicio Nacional de Areas Naturales Protegidas por el Estado 15036Peru Sanidad Animal-Facultad de zootecnia Universidad Nacional Agraria La MolinaLima 15012Peru Laboratorio de Microbiologia Facultad de Medicina Veterinaria y ZootecniaUniversidad CientUfica del SurLima 15067Peru Laboratorio de Analisis Clinico Moraleslab SAC MoralesSan Martin 22201Peru Asociacion Ecosistemas Andinos(ECOAN) Cuzco 08002Peru Pharmacology and Toxicology Graduate Group University of CaliforniaDavisDA 95616USA Global Health Initiative Wabash CollegeCrawfordsvilleIN 47933USA Facultad de Ciencias Biologicas Universidad Nacional Mayor de San MarcosLima 15081Peru Facultad de Medicina Veterinaria Universidad Nacional Hermilio ValdizanHuanuco10160Peru Asociacion Peruana de Helmintologia e Invertebrados Afines Lima 15054Peru Laboratorio de Ecologia y Biodiversidad Animal Universidad Nacional Federico VillarrealEl AgustinoLima 15007Peru Laboratorio de Invertebrados Universidad Ricardo Palma-Santiago de SurcoLima 15537Peru Department of Biology San Francisco State UniversitySan FranciscoCA 94132USA

Characterizing the diversity and structure of host–parasite communities is crucial to understandingtheir eco-evolutionary dynamics.Malaria and related haemosporidian parasites are responsible forfitness loss and mortality in bird species worldwide.However,despite exhibiting the greatest ornithologicalbiodiversity,avian haemosporidians from Neotropical regions are quite unexplored.Here,we analyze the genetic diversity of bird haemosporidian parasites(Plasmodium andHaemoproteus)in 1,336 individuals belonging to 206 bird species to explore for differences in diversityof parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions.Wedetected 70 different haemosporidian lineages infecting 74 bird species.We showed that 25 out ofthe 70 haplotypes had not been previously recorded.Moreover,we also identified 81 new host–parasite interactions representing new host records for these haemosporidian parasites.Our outcomesrevealed that the effective diversity(as well as the richness,abundance,and Shannon–Weaver index)for both birds and parasite lineages was higher in Amazon basin ecoregions.Furthermore,we also showed that ecoregions with greater diversity of bird species also had highparasite richness,hence suggesting that host community is crucial in explaining parasite richness.Generalist parasites were found in ecoregions with lower bird diversity,implying that the abundanceand richness of hosts may shape the exploitation strategy followed by haemosporidian parasites.These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidianlineages.Further studies analyzing host distribution and specificity of these parasites inthe tropics will provide important knowledge about phylogenetic relationships,phylogeography,and patterns of evolution and distribution of haemosporidian parasites.

关键词： Amazonia avian malaria generalist parasite habitat specificity Haemoproteus Plasmodium specialist parasite

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Vortex Shedding Lock-in on Tapered Poles with Polygonal Cross-Section

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Open journal of Fluid Dynamics 2022年第2期12卷 127-153页

作者： jaime A. Ocampo Steven H. Collicott Robert j. Connor School of Aeronautics and Astronautics Purdue University West Lafayette USA Lyles School of Civil Engineering Purdue University West Lafayette USA

A study to investigate the effects of taper on vortex shedding coherence on High Mast Lighting Towers (HMLT) with models of eight-, twelve-, and sixteen-sided polygonal cross-section was performed in Purdue’s Boeing Low-Speed Wind Tunnel. Partial tower models were mounted on springs to recreate a flutter phenomenon seen on high mast lighting towers and data was taken using a stationary configuration within the wind tunnel. The model was later oscillated at specified frequencies and amplitudes and the resulting wake and surface pressures were recorded and compared to the stationary cases. The researchers aim to study the characteristics of a “lock-in” phenomenon, that is, a region of pole height where there is a vortex cell with a single shedding frequency, instead of different shedding frequencies for different diameters as Strouhal theory dictates. Results show the existence of vortex cell shedding for clamped models. Using a motor and a forcing cam to recreate the elastic movement of the HMLT in ambient conditions has yielded a specific range of diameters to determine the size of the locked in vortex cells. According to standard Department of Transportation manufacturing standards for tapered HMLT, the lock in distance for small excitations (0.254 cm) would be approximately 305 cm in tower height.

关键词： Vortex Shedding Lock-In Tower Aerodynamics

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Practice parameters for the use of actigraphy in the military operational context: the Walter Reed Army Institute of Research Operational Research Kit-Actigraphy(WORK-A)

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Military Medical Research 2021年第1期8卷 103-115页

作者： jaime K.Devine jake Choynowski Tina Burke Kajsa Carlsson Vincent F.Capaldi Ashlee B.McKeon Walter j.Sowden Operational Fatigue and Performance Institutes for Behavior ResourcesBaltimoreMD 21218USA Behavioral Biology Branch Walter Reed Army Institute of Research503 Robert Grant AveSilver SpringMD 20910USA Tripler Army Medical Center HonoluluHI 96859USA

Background: The Walter Reed Army Institute of Research(WRAIR) Operational Research Kit-Actigraphy(WORK-A) is a set of unique practice parameters and actigraphy-derived measures for the analysis of operational military sleep patterns. The WORK-A draws on best practices from the literature and comprises 15 additional descriptive variables. Here, we demonstrate the WORK-A with a sample of United States Army Reserve Officers’ Training Corps(ROTC) cadets(n=286) during a month-long capstone pre-commissioning training exercise.Methods: The sleep of ROTC cadets(n=286) was measured by Philips Actiwatch devices during the 31-day training exercise. The preliminary effectiveness of the WORK-A was tested by comparing differences in sleep measures collected by Actiwatches as calculated by Philips Actiware software against WORK-A-determined sleep measures and self-report sleep collected from a subset of ROTC cadets(n=140).Results: Actiware sleep summary statistics were significantly different from WORK-A measures and self-report sleep(P≤0.001). Bedtimes and waketimes as determined by WORK-A major sleep intervals showed the best agreement with self-report bedtime(22:21±1:30 vs. 22:13±0:40, P=0.21) and waketime(04:30±2:17 vs. 04:31±0:47, P=0.68). Though still significantly different, the discrepancy was smaller between the WORK-A measure of time in bed(TIB) for major sleep intervals(352±29) min and self-report nightly sleep duration [(337±57) min, P=0.006] than that between the WORK-A major TIB and Actiware TIB [(177±42) min, P≤0.001].Conclusions: Default actigraphy methods are not the most accurate methods for characterizing soldier sleep, but reliable methods for characterizing operational sleep patterns is a necessary first step in developing strategies to improve soldier readiness. The WORK-A addresses this knowledge gap by providing practice parameters and a robust variety of measures with which to profile sleep behavior in service members.

关键词： Actigraphy Sleep-wake patterns Military sleep assessment Operational environment Scoring methodology

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