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Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration

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Journal of Forestry Research 2022年第3期33卷 741-753页

作者： Tzeidle N.Wasserman Amy E.m.Waltz John Paul Roccaforte Judith D.Springer joseph E.Crouse Ecological Restoration Institute Northern Arizona UniversityP.O.Box 15017FlagstaffAZ86011-5017USA

Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United *** focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review *** showed that the effects of thinning and burning treatments on regeneration depended on time since *** thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and *** were mixed results in the short-term(m studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments *** studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals.

关键词： Regeneration Ponderosa pine Frequent-fire Treatments Thinning Burning

Seed value influences cache pilfering rates by desert rodents

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Integrative Zoology 2019年第1期14卷 75-86页

作者： Stephen B.VANDER WALL Lindsay A.DImITRI William S.LONGLAND joseph D.m.WHITE Department of Biology and Program in Ecology Evolution and Conservation BiologyUniversity of NevadaRenoUSA USDA Agricultural Research ServiceRenoNevadaUSA Department of Biological Sciences University of Cape TownCape TownRepublic of South Africa

Some rodents gather and store *** many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compounds,and germination *** their consumption and dispersal of seeds,rodents act as agents of natural selection on seed traits,and those traits influence how rodents *** seeds that are scatter-hoarded by rodents are pilfered,or stolen,by other rodents,and seed traits also likely influence pilfering rates and seed fates of pilfered *** clarify coevolutionary relationships between rodents and the plants that they disperse,one needs to understand the role of seed traits in rodent foraging *** compared how the seeds of 4 species of plants that are dispersed by scatter-hoarding animals and that differ in value(singleleaf piñon pine,Pinus monophylla;desert peach,Prunus andersonii;antelope bitterbrush,Purshia tridentata;Utah juniper,Juniperus osteosperma)were pilfered and recached by *** hundred artificial caches of the 4 seed species(25 per species)were prepared,and removal by rodents was *** pilfered high-value seeds more rapidly than the other *** peach seeds,which contain toxic secondary compounds,were more frequently *** low value seeds like Utah juniper and antelope bitterbrush were pil-fered more slowly and were sometimes left at cache sites,and seeds of the latter species were transported shorter distances to new cache *** background density of seeds also appeared to influence the relative value of seeds.

关键词： desert rodents food storage granivory pilfering scatter-hoarding seed dispersal seed traits

Packaging and degradability properties of polyvinyl alcohol/gelatin nanocomposite films filled water hyacinth cellulose nanocrystals

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Journal of Bioresources and Bioproducts 2021年第2期6卷 168-185页

作者： Henry C.Oyeoka Chinomso m.Ewulonu Iheoma C.Nwuzor Chizoba m.Obele joseph T.Nwabanne Department of Polymer and Textile Engineering Nnamdi Azikiwe UniversityP.M.B.5025AwkaNigeria Department of Chemical Engineering Nnamdi Azikiwe UniversityP.M.B.5025AwkaNigeria Technical Institute of Physics and Chemistry Chinese Academy of Sciences29 Zhongguancun East RoadHaidian DistrictBeijing 100190China

Cellulose nanocrystals isolated from water hyacinth fiber(WHF)have been studied as a reinforcement for polyvinyl alcohol(PVA)-gelatin *** composite design was used to study and optimize effects of the PVA,gelatin and cellulose nanocrystal(CNC)concentration on tensile strength and elongation of formed *** results of this study showed that WHF CNC had a diameter range of 20-50 nm produced films reaching 13.8 mPa tensile *** stability of the films was improved from 380℃ to 385℃ in addition of CNCs and maximum storage modulus of 3 GPa were observed when 5 wt%CNC was ***,water absorption,water vapour permeability(WVP)and moisture uptake of the films decreased in addition of CNC to the PVA-gelatin *** uptake decreased from 22.50%to 19.05%while the least WVP when 10 wt%CNC added was 1.64×10^(-6)g/(m·h·Pa).These results show possibility for industrial application of WHF CNC and PVA-gelatin blends in biodegradable films for on-the-go food wrappers.

关键词： WATER hyacinth Polyvinyl alcohol Gelatin Cellulose nanocrystals Central composite design Packaging films Degradation properties

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Journal of Sport and Health Science 2023年第3期12卷 414-422页

作者： joseph m.Bano Rebecca J.mcAdams Kristin J.Roberts Jingzhen Yang Lara B.mcKenzie Center for Injury Research and Policy Abigail Wexner Research Institute at Nationwide Children's HospitalColumbusOH 43205USA Department of Pediatrics The Ohio State UniversityCollege of MedicineColumbusOH 43205USA Division of Epidemiology The Ohio State UniversityCollege of Public HealthColumbusOH 43210USA

Background:Lacrosse is one of the fastest-growing sports in the United *** rules regarding permitted contact differ by sex and *** are no known studies using a nationally representative data set to analyze lacrosse injury patterns over several years by sex and age in the youth ***:A retrospective analysis was performed using data from the National Electronic Injury Surveillance System for youth aged 11-18 years who were treated for lacrosse-related injuries in *** departments from 2000 to *** on our review of the case narratives,we created and coded a new injury-mechanism *** generated national estimates from 6406 ***:An estimated 206,274 lacrosse-related injuries to youths aged 11-18 years were treated in *** departments from 2000 to *** rate of injuries per 10,000 significantly increased from 1.9 in 2000 to a peak of 5.3 in 2012(pmechanism,body part injured,and diagnosis differed by *** were 1.62 times(95%confidence interval(95%CI):1.25-2.09)more likely than girls to be injured by player-to-player *** were 2.21 times(95%CI:1.96-2.49)more likely than boys to have non-contact ***,as age increased,the percentage of injuries from lacrosse sticks decreased and player-toplayer contact ***:Despite additional protective regulations in the sport,lacrosse is an important source of injury where we continue to see differences by sex and *** study supports the continuation,modification,and addition of rules aimed at reducing lacrosse injury risk.

关键词： Lacrosse National Electronic Injury Surveillance System Sex differences Youth injuries

Collection,curation and the use of humidification to restore nest shape in a research museum bird nest collection

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Avian Research 2021年第3期12卷 399-411页

作者： Tonya m.Haff Natalie Tees Kathryn Wood E.margaret Cawsey Leo joseph Clare E.Holleley Australian National Wildlife Collection National Research Collections AustraliaCSIROGPO Box 1700CanberraACT 2601Australia

Background:Bird nests are an important part of avian *** are a powerful tool for studying not only the birds that built them,but a wide array of topics ranging from parasitology,urbanisation and climate change to *** this,bird nests tend to be underrepresented in natural history collections,a problem that should be redressed through renewed focus by collecting ***:Here we outline the history and current best practice collection and curatorial methods for the nest col-lection of the Australian National Wildlife Collection(ANWC).We also describe an experiment conducted on nests in the ANWC using ultrasonic humidification to restore the shape of nests damaged by inappropriate ***:The experiment showed that damaged nests can be successfully reshaped to close to their original ***,restored nests were significantly closer to their original shape than they were prior to ***,even nests damaged by years of neglect may be fully incorporated into active research *** practice techniques include extensive note taking and photography in the field,subsampling of nests that cannot or should not be collected,appropriate field storage,metadata management,and prompt treatment upon arrival at the collec-tion ***:Renewed focus on nest collections should include appropriate care and restoration of current col-lections,as well as expansion to redress past *** could include collaboration with researchers studying or monitoring avian nesting ecology,and nest collection after use in bird species that rebuild anew each nesting *** expansion of museum nest collections will allow researchers and natural history collections to fully realise the scientific potential of these complex and beautiful specimens.

关键词： Best practice Bird Curation Nest Nest shape Natural history collection Humidification Object restoration Preservation

Speech Separation methodology for Hearing Aid

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Computer Systems Science & Engineering 2023年第2期44卷 1659-1678页

作者： joseph Sathiadhas Esra Y.Sukhi meenakshi Sundararajan Engineering College ChennaiTamil naduIndia R.m.K.Engineering College KavaraipettaiTamil naduIndia

In the design of hearing aids(HA),the real-time speech-enhancement is *** digital hearing aids should provide high signal-to-noise ratio,gain improvement and should eliminate *** generic hearing aids the perfor-mance towards different frequencies varies and non *** noise can-cellation and speech separation methods drops the voice magnitude under the noise *** performance of the HA for frequency response is non *** noise suppression methods reduce the required signal strength ***,the performance of uniform sub band analysis is poor when hearing aid is *** this paper,a speech separation method using Non-negative matrix Fac-torization(NmF)algorithm is proposed for wavelet *** Proposed non-uniformﬁlter-bank was validated by parameters like band power,Signal-to-noise ratio(SNR),mean Square Error(mSE),Signal to Noise and Dis-tortion Ratio(SINAD),Spurious-free dynamic range(SFDR),error and *** speech recordings before and after separation was evaluated for quality using objective speech quality measures International Telecommunication Union-Telecommunication standard ITU-T P.862.

关键词： Speech separation waveletﬁlter independent component analysis(ICA) non-negative matrix factorization(NmF) fejer-korovkin(FK) signal-to-noise ratio(SNR)

Influences of Annealing Temperature and Doping Concentration on microstructural and Optical Properties of CeO_2:Sm^(3+) Nanocrystals

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Acta metallurgica Sinica(English Letters) 2015年第6期28卷 758-765页

作者： G.Vimal Kamal P.mani P.R.Biju Cyriac joseph N.V.Unnikrishnan m.A.Ittyachen School of Pure and Applied Physics Mahatma Gandhi University

Nanocrystals of CeO2 with different doping concentrations of Sm3＋ were synthesized by a novel and cost- effective method. The crystal structure, morphology and particle size were systematically investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Effects of the annealing temperature and doping concentrations on the microstructural properties of the crystals were studied. X-ray diffraction analysis indicates that the cubic structure of the CeO2 is not affected by the doping of Sm3＋ up to a doping concentration of 20%. Different structural parameters such as lattice constant, surface area, bulk density and porosity of the crystal were determined and discussed. microscopic images of the CeO2：Sm3＋ suggest that the thermal decomposition of oxalate precursor is a suitable synthesis pathway to produce uniform-sized microparticles and nanoparticles. The influences of annealing temPerature and doping concentration of Sm3＋ on the optical properties of the nanocrystals were also discussed. The photoluminescence excitation spectra reveal that the charge transfer band is redshifted with increasing annealing temperatures. Emission attains its maximum intensity for Sm3＋ concentration of 1%, and higher concentrations lead to emission quenching.

关键词： microstructure Strain Photoluminescence CeO2:Sm3+ nanocrystal Dopingconcentration Annealing temperature

measurement of oxygen consumption rates of human renal proximal tubule cells in an array of organ-on-chip devices to monitor drug-induced metabolic shifts

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microsystems & Nanoengineering 2022年第5期8卷 149-160页

作者： Samuel H.Kann Erin m.Shaughnessey Jonathan R.Coppeta Hesham Azizgolshani Brett CIsenberg Else m.Vedula Xin Zhang joseph L.Charest Draper Scholar 555 Technology SquareCambridgeMA 02139USA Department of mechanical Engineering Boston University110 Cummington MallBostonMA 02215USA Department of Biomedical Engineering Tufts University4 Colby StreetMedfordMA 02155USA Draper 555 Technology SquareCambridgeMA 02139USA Present address:Biogen 225 Binney StreetCambridgeMA 02142USA

measurement of cell metabolism in moderate-throughput to high-throughput organ-on-chip(OOC)systems would expand the range of data collected for studying drug effects or disease in physiologically relevant tissue ***,current measurement approaches rely on fluorescent imaging or colorimetric assays that are focused on endpoints,require labels or added substrates,and lack real-time ***,we integrated optical-based oxygen sensors in a high-throughput OOC platform and developed an approach for monitoring cell metabolic activity in an array of membrane bilayer *** membrane bilayer device supported a culture of human renal proximal tubule epithelial cells on a porous membrane suspended between two microchannels and exposed to controlled,unidirectional perfusion and physiologically relevant shear stress for several *** the first time,we measured changes in oxygen in a membrane bilayer format and used a finite element analysis model to estimate cell oxygen consumption rates(OCRs),allowing comparison with OCRs from other cell culture ***,we demonstrated label-free detection of metabolic shifts in human renal proximal tubule cells following exposure to FCCP,a drug known for increasing cell oxygen consumption,as well as oligomycin and antimycin A,drugs known for decreasing cell oxygen *** capability to measure cell OCRs and detect metabolic shifts in an array of membrane bilayer devices contained within an industry standard microtiter plate format will be valuable for analyzing flowresponsive and physiologically complex tissues during drug development and disease research.

关键词： metabolism culture OCR

Comparative efficacy of sodium glucose cotransporter-2 inhibitors in the management of type 2 diabetes mellitus:A real-world experience

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World Journal of Diabetes 2024年第3期15卷 463-474页

作者： Lubna Islam Dhanya Jose mohammed Alkhalifah Dania Blaibel Vishnu Chandrabalan joseph m Pappachan Department of Endocrinology and metabolism Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Department of Community medicine Goa Medical CollegeGoa 403202India Department of Family medicine King Faisal Specialist HospitalRiyadh 11564Saudi Arabia Department of Data Science Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Faculty of Science Manchester Metropolitan UniversityAll Saints BuildingManchester M156BHUnited Kingdom Faculty of Biology Medicine and HealthThe University of ManchesterManchester M139PLUnited Kingdom

BACKGROUND Sodium glucose cotransporter-2 inhibitors(SGLT-2i)are a class of drugs with modest antidiabetic efficacy,weight loss effect,and cardiovascular benefits as proven by multiple randomised controlled trials(RCTs).However,real-world data on the comparative efficacy and safety of individual SGLT-2i medications is *** To study the comparative efficacy and safety of SGLT-2i using real-world clinical *** We evaluated the comparative efficacy data of 3 SGLT-2i drugs(dapagliflozin,canagliflozin,and empagliflozin)used for treating patients with type 2 diabetes *** on the reduction of glycated hemoglobin(HbA1c),body weight,blood pressure(BP),urine albumin creatinine ratio(ACR),and adverse effects were recorded *** Data from 467 patients with a median age of 64(14.8)years,294(62.96%)males and 375(80.5%)Caucasians were *** diabetes duration was 16.0(9.0)years,and the duration of SGLT-2i use was 3.6(2.1)***-2i molecules used were dapagliflozin 10 mg(n=227;48.6%),canagliflozin 300 mg(n=160;34.3%),and empagliflozin 25 mg(n=80;17.1).Baseline median(interquartile range)HbA1c in mmol/mol were:dapagliflozin-78.0(25.3),canagliflozin-80.0(25.5),and empagliflozin-75.0(23.5)*** respective median HbA1c reduction at 12 months and the latest review(just prior to the study)were:66.5(22.8)&69.0(24.0),67.0(16.3)&66.0(28.0),and 67.0(22.5)&66.5(25.8)respectively(Pmparisons from baseline).Significant improvements in body weight(in kilograms)from baseline to study end were noticed with dapagliflozin-101(29.5)to 92.2(25.6),and canagliflozin 100(28.3)to 95.3(27.5)*** reductions in median systolic and diastolic BP,from 144(21)mmHg to 139(23)mmHg;(P=0.015),and from 82(16)mmHg to 78(19)mmHg;(Pmicroalbuminuria was observed with canagliflozin only[ACR 14.6(42.6)at baseline to 8.9(23.7)at the study end;P=0.043].Adverse effects

关键词： Sodium glucose cotransporter-2 inhibitors Empagliflozin Canagliflozin Dapagliflozin Type 2 diabetes mellitus Cardiovascular disease Albumin creatinine ratio Diabesity