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A note on the estimation of variance for big bAF sampling

Forest Ecosystems 2020年第4期7卷 819-832页

作者： Jeffrey H.Gove Timothy G.Gregoire mark J.Ducey Thomas b.Lynch USDA Forest Service Northern Research Station271 Mast RoadDurham NH03824USA. School of Forestry&Environmental Studies Yale University360 Prospect StNew Haven CT06511USA. Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham NH03824USA. Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater OK74078USA.

background:The double sampling method known as“big bAF sampling”has been advocated as a way to reduce sampling effort while still maintaining a reasonably precise estimate of volume.A well-known method for variance determination,bruce’s method,is customarily used because the volume estimator takes the form of a product of random ***,the genesis of bruce’s method is not known to most foresters who use the method in ***:We establish that the Taylor series approximation known as the Delta method provides a plausible explanation for the origins of bruce’s *** were conducted on two different tree populations to ascertain the similarities of the Delta method to the exact variance of a ***,two alternative estimators for the variance of individual tree volume-basal area ratios,which are part of the estimation process,were compared within the overall variance estimation ***:The simulation results demonstrate that bruce’s method provides a robust method for estimating the variance of inventories conducted with the big bAF *** simulations also demonstrate that the variance of the mean volume-basal area ratios can be computed using either the usual sample variance of the mean or the ratio variance estimators with equal accuracy,which had not been shown previously for big bAF ***:A plausible explanation for the origins of bruce’s method has been set forth both historically and mathematically in the Delta *** most settings,there is evidently no practical difference between applying the exact variance of a product or the Delta method—either can be used.A caution is articulated concerning the aggregation of tree-wise attributes into point-wise summaries in order to test the correlation between the two as a possible indicator of the need for further covariance augmentation.

关键词： bitterlich sampling Delta method Double sampling Forest inventory Horizontal point sampling Variance of a product

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An approximate point-based alternative for the estimation of variance under big bAF sampling

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Forest Ecosystems 2021年第3期8卷 439-457页

作者： Thomas b.Lynch Jeffrey H.Gove Timothy G.Gregoire mark J.Ducey Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA USDA Forest Service Northern Research Station271 Mast RoadDurham 03824NHUSA Yale School of Environment Yale University360 Prospect StNew Haven 06511CTUSA Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham 03824NHUSA

background:A new variance estimator is derived and tested for big bAF(basal Area Factor)sampling which is a forest inventory system that utilizes bitterlich sampling(point sampling)with two bAF sizes,a small bAF for tree counts and a larger bAF on which tree measurements are made usually including DbHs and heights needed for volume ***:The new estimator is derived using the Delta method from an existing formulation of the big bAF estimator as consisting of three sample *** new formula is compared to existing big bAF estimators including a popular estimator based on bruce’s ***:Several computer simulation studies were conducted comparing the new variance estimator to all known variance estimators for big bAF currently in the forest inventory *** simulations the new estimator performed well and comparably to existing variance ***:A possible advantage of the new estimator is that it does not require the assumption of negligible correlation between basal area counts on the small bAF factor and volume-basal area ratios based on the large bAF factor selection trees,an assumption required by all previous big bAF variance estimation *** this correlation was negligible on the simulation stands used in this study,it is conceivable that the correlation could be significant in some forest types,such as those in which the DbH-height relationship can be affected substantially by density perhaps through *** derived a formula that can be used to estimate the covariance between estimates of mean basal area and the ratio of estimates of mean volume and mean basal *** also mathematically derived expressions for bias in the big bAF estimator that can be used to show the bias approaches zero in large samples on the order of 1n where n is the number of sample points.

关键词： bitterlich sampling Delta method Double sampling Estimator bias Forest inventory Horizontal point sampling Variance of a product Volume basal area ratio Covariance estimation

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Species Account of Anura ns from the Western Slope of Mt. Kita nglad, Mindanao Island, Philippines

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Asian Herpetological Research 2021年第1期12卷 76-87页

作者： Elsa May Delima bARON mark Oliver D.MARIN benjo A.LOGRAMONTE Alma b.MOHAGAN biology Natural Sciencesand Math Division.Arts and Sciences DepartmentSan Pedro CollegeDavao City 8000MindanaoPhilippines biology Department College of Arts and SciencesCentral Mindanao UniversityMusuanBukidnon 8714MindanaoPhilipines

The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.

关键词： key biodiversity area Mindanao faunal region Philippine endemic anurans upper elevation forests wildlife inventory in Mindanao

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Metal-dielectric-metal plasmonic waveguide devices for manipulating light at the nanoscale

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Chinese Optics Letters 2009年第4期7卷 302-308页

作者： Georgios Veronis Zongfu Yu Sukru Ekin Kocaba David A. b. Miller mark L. brongersma Shanhui Fan Department of Electrical and Computer Engineering and Center for Computation and Technology Louisiana State University Baton Rouge LA 70803 USA Ginzton LaSoratory Stanford University Stanford CA 94305 USA GeSalle LaSoratory of Advanced Materials Stanford University Stanford CA 94305 USA

We review some of the recent advances in the development of subwavelength plasmonic devices for manipulating light at the nanoseale, drawing examples from our own work in metal-dielectric-metal （MDM） plasmonic waveguide devices. We introduce bends, splitters, and mode converters for MDM waveguides with no additional loss. We also demonstrate that optical gain provides a mechanism for on/off switching in MDM plasmonic waveguides. Highly efficient compact couplers between dielectric waveguides and MDM waveguides are also introduced.

关键词： Metals Multiplexing Nanotechnology Optical waveguides Plasmons Waveguide components Waveguides

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Differentially expressed genes in hepatocellular carcinoma induced by woodchuck hepatitis b virus in mice

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World Journal of Gastroenterology 2001年第4期7卷 575-578页

作者： mark Feitelson Department of Pathology Second Military Medical UniversityShanghai 200433China

INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the *** mechanism of carcinogenesis is unknown,although it is widely accepted that HbV and HCV are clsely related to liver cancer[1-5[1-5].Previously,a variety of studies have described the differences in gene expression which distinguished tumor from nontumor[6-11].Cloning of the genes,especially the genes associated with HbV and HCV,is still very important to account for the development of liver cancer.

关键词： Animals Carcinoma, Hepatocellular Cloning, Molecular DNA, Complementary Databases, Nucleic Acid Gene Expression Regulation, Neoplastic Gene Expression Regulation, Viral Hepatitis b Hepatitis b Virus, Woodchuck Humans Mice Polymerase Chain Reaction Research Support, Non-U.S. Gov't

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Exercise training improves long-term memory in obese mice

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Life Metabolism 2024年第1期3卷 37-50页

作者： Oliver K.Fuller Casey L.Egan Tina L.Robinson Nimna Perera Heidy K.Latchman Lauren V.Terry Emma D.McLennan Carolina Chavez Emma L.burrows John W.Scott Robyn M.Murphy Henriette van Praag Martin Whitham mark A.Febbraio Monash Institute of Pharmaceutical Sciences Monash UniversityMelbourneVictoria3052Australia La Trobe Institute for Molecular Science La Trobe UniversityMelbourneVictoria3086Australia Florey Institute of Neuroscience and Mental Health University of MelbourneMelbourneVictoria3052Australia Department of biomedical Sciences Charles E.Schmidt College of Medicineand Stiles-Nicholson Brain InstituteFlorida Atlantic UniversityJupiterFL 33458United States College of Life and Environmental Sciences University of BirminghamEdgbastonBirmingham B152TTUnited Kingdom

Obesity has been linked to a range of pathologies,including *** contrast,regular physical activity is associated with the prevention or reduced progression of ***,physical activity can improve memory and spatial cognition,reduce age-related cognitive decline,and preserve brain volume,but the mechanisms are not fully ***,we investigated whether any detrimental effects of high-fat diet(HFD)-induced obesity on cognition,motor behavior,adult hippocampal neurogenesis,and brain-derived neurotrophic factor(bDNF)could be mitigated by voluntary exercise training in male C57bl/6 ***-induced impairment of motor function was not reversed by ***,voluntary wheel running improved long-term memory and increased hippocampal neurogenesis,suggesting that regular physical activity may prevent cognitive decline in obesity.

关键词： obesity exercise cognition

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SGT1 Is Induced by the Potato virus X TGbp3 and Enhances Virus Accumulation in Nicotiana benthamiana

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Molecular Plant 2012年第5期5卷 1151-1153页

作者： Chang-Ming Ye Vicky Kelly mark Payton Martin b. Dickman Jeanmarie Verchot Department of Entomology and Plant Pathology Oklahoma State UniversityStillwaterOK 74078USA Department of Statistics Oklahoma State University StillwaterOK 74078USA Institute for Plant Genomics and biotechnology Department of Plant Pathology and MicrobiologyTexas A&M UniversityCollege StationTX 77843USA

Dear Editor, Host chaperone proteinsarecritical factors in plant virus infec- tion. One ofthe most commonly identified host factors involved in plant virus infection is Hsp70, which functions in ATP hydroly- sis, protein folding, assembly of protein complexes, and translo- cation between cellular compartments. A comparative study of plant virus infection, including Potato virus X （PVX）, reported that Hsp70 is up-regulated by virus infection and possibly con- tributes to pathogenesis in both Arabidopsis and N. benthami- ana plants （Aparicio et al., 2005）. Cytosolic Hsp70 interacts with the tombusvirus and tymovirus replication complexes （Wang et al., 2009）, the potyvirus coat protein （Hafren et al., 2010）, and closteroviruses encode an HSP70 homolog that functions to enable virus intercellular transport （Agranovsky et al., 1998）.

关键词： Accumulation Potato Nicotiana

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Conscious or unconscious:The impact of sedation choice on colon adenoma detection

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World Journal of Gastroenterology 2011年第34期17卷 3912-3915页

作者： mark Metwally Nicholas Agresti William b Hale Victor Ciofoaia Ryan O＇Connor Michael b Wallace Jonathan Fine Yun Wang Seth A Gross Department of Gastroenterology Norwalk Hospital 34 Stevens St. Norwalk CT 06850 United States Department of Gastroenterology Mayo Clinic 4500 San Pablo Road FL 32224 United States Department of Statistics Yale University 333 Cedar Street New Haven CT 06510 USA 34 Stevens St. Norwalk CT 06850 United States

AIM: To determine if anesthesiologist-monitored useof propofol results in improved detection of adenomaswhen compared with routine conscious sedation. METHODS: This retrospective study was conductedat two separate hospital-based endoscopy units whereapproximately 12 000 endoscopic procedures are permed annually, with one endoscopy unit exclusivelyusing anesthesiologist-monitored propofol. Three thousand two hundred and fifty-two patients underwent initial screening or surveillance colonoscopies. Our primaryend point was the adenoma detection rate, def ined asthe number of patients in whom at least one adenomawas found, associated with the type of sedation. RESULTS: Three thousand two hundred and fi ftytwooutpatient colonoscopies were performed by fi ve selected endoscopists. At least one adenoma was detected in 27.6% of patients (95% CI = 26.0-29.1) with no difference in the detection rate between the anesthes-ologist propofol and group and the gastroenterologist-midazolam/fentanyl group (28.1% vs 27.1%, P = 0.53). CONCLUSION: The type of sedation used during colonoscopy does not affect the number of patients in whom adenomatous polyps are detected.

关键词： Sedation Colonoscopy Adenoma

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Re-evaluation of the mechanical properties and creep resistance of commercial magnesium die-casting alloy AE44

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Journal of Magnesium and Alloys 2021年第5期9卷 1552-1560页

作者： Suming Zhu Trevor b.Abbott Jian-Feng Nie Hua Qian Ang Dong Qiu Kazuhiro Nogita mark A.Easton School of Engineering RMIT UniversityCarltonVictoria 3053Australia Department of Materials Science and Engineering Monash UniversityVictoria 3800Australia Magontec Limited SydneyNew South Wales 2000Australia School of Mechanical and Mining Engineering The University of QueenslandSt LuciaQueensland 4072Australia

This paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44(Mg-4Al-4RE)in light of the influence of minor Mn *** is shown that the Mn-containing AE44 exhibits distinct age hardening response upon direct ageing(T5)due to the precipitation of nanoscale Al-Mn particles,as reported previously in a similar *** T5 ageing leads to a significant improvement in strength with similar ***,the T5-aged AE44 has a remarkably better strength-ductility combination than most Mg die-casting alloys and even the Al die-casting alloy *** Mn addition is also shown to be critical for the creep resistance of AE44 whereas the influence of the RE constituent is not as significant as previously thought,which reaffirms that precipitation hardening of theα-Mg matrix is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of die-cast Mg *** findings in this work could provide new application perspectives for AE44,particularly in the automotive industry.

关键词： Magnesium alloys Manganese Precipitation hardening Mechanical properties Creep Die casting

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Assessing ecological and physiological costs of melanism in North American Papilio glaucus females: two decades of dark morph frequency declines

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Insect Science 2020年第3期27卷 583-612页

作者： J.mark Scriber Department of Entomology Michigan State UniversityEast LansingMichiganUSA McGuire Center for Lepidoptera and biodiversity Florida Museum of Natural HistoryUniversity of FloridaGainesvilleFloridaUSA

Polymorphisms for melanic form of insects may provide various selective ***,melanic alleles may have significant/subtle pleiotrophic“costs.”Several potential pleiotrophic effects of the W(=Y)‐linked melanism gene in Papilio glaucus L.(Lepidoptera)showed no costs for melanic versus yellow in adult size,oviposition preferences,fecundity,egg viability,larval survival/growth rates,cold stress tolerance,or postdiapause emergence *** selection(males choosing yellow rather than mimetic dark females)had been suggested to provide a balanced polymorphism in ***,but spermatophore counts in wild females and direct field tethering studies of size‐matched pairs of virgin females(dark and yellow),show that male preferences are random or frequency‐dependent from Florida to Michigan,providing no yellow counter‐*** frequency declines of dark(melanic/mimetic)females in *** populations are shown in several major populations from Florida(27.3°N latitude)to Ohio(38.5°N).Summer temperatures have increased significantly at all these locations during this time(1999–2018),but whether dark morphs may be more vulnerable(in any stage)to such climate warming remains to be *** potential reasons for the frequency declines in mimetic females are discussed:(i)genetic introgression of Z‐linked melanism suppressor genes from ***(R&J)and the hybrid species,***(Pavulaan&Wright),(ii)differential developmental incompatibilities,or Haldane effects,known to occur in hybrids,(iii)selection against intermediately melanic(“dusty”)females(with the W‐linked melanic gene,b+)which higher temperatures can cause.

关键词： climate warming ecology of melanism incomplete mimicry pleiotrophic costs

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