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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(ears)with both increasing and decreasing regeneration,and a general increase in regeneration 11−20 years *** long-term 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

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Femoral impaction grafting

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World Journal of Orthopedics 2013年第1期4卷 7-11页

作者： john A Scanelli Thomas e Brown Department of Orthopedic Surgery University of Virginia School of Medicine Charlottesville VA 22908 United States

Femoral impaction grafting is a reconstruction option applicable to both simple and complex femoral component revisions. It is one of the preferred techniques for reconstructing large femoral defects when the isthmus is non-supportive. The available level of evidence is primarily derived from case series, which shows a mean survivorship of 90.5%, with revision or re-operation as the end-point, with an average follow-up of 11 years. The rate of femoral fracture requiring re-operation or revision of the component varies between several large case series, ranging from 2.5% to 9%, with an average of 5.4%.

关键词： Femoral impaction grafting Femoral revision Bone grafting Revision total hip arthroplasty Bone loss

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Comparative Transmission Genetics of Introgressed Chromatin in Gossypium Species

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棉花学报 2008年第S1期20卷 117-页

作者： WAGHMARe Vijay N ROGeRS Carl J bowers john e PATeRSON Andrew H Division of Crop Improvement CICR University of Georgia Athens

Wild relatives and un-adapted germplasm of crop species harbors several adaptive *** of genes for economic and adaptive traits brings in novel genetic variation into the gene

关键词： Comparative Transmission Genetics of Introgressed Chromatin in Gossypium Species

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Longwave infrared multispectral image sensor system using aluminum-germanium plasmonic filter arrays Noor e

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Nano Research 2023年第7期16卷 10018-10025页

作者： Karishma Shaik Bryce Widdicombe Dechuan Sun Sam e john Dongryeol Ryu Ampalavanapillai Nirmalathas Ranjith R Unnithan Department of electrical and electronic engineering University of MelbourneParkvilleVIC 3010Australia Department of Biomedical engineering University of MelbourneParkvilleVIC 3010Australia Department of Infrastructure engineering University of MelbourneParkvilleVIC 3010Australia

A multispectral camera records image data in various wavelengths across the electromagnetic spectrum to acquire additional information that a conventional camera fails to *** the advent of high-resolution image sensors and color filter technologies,multispectral imagers in the visible wavelengths have become popular with increasing commercial viability in the last ***,multispectral imaging in longwave infrared(LWIR,8-14μm)is still an emerging area due to the limited availability of optical materials,filter technologies,and high-resolution *** from LWIR multispectral cameras can capture emission spectra of objects to extract additional information that a human eye fails to capture and thus have important applications in precision agriculture,forestry,medicine,and object *** this work,we experimentally demonstrate an LWIR multispectral image sensor with three wavelength bands using optical elements made of an aluminum(Al)-based plasmonic filter array sandwiched in germanium(Ge).To realize the multispectral sensor,the filter arrays are then integrated into a three-dimensional(3D)printed wheel stacked on a low-resolution monochrome thermal *** prototype device is calibrated using a blackbody and its thermal output has been enhanced with computer vision *** applying a state-of-theart deep learning method,we have also reconstructed multispectral images to a better spatial ***,our work demonstrates a versatile spectral thermography technique for detecting target signatures in the LWIR range and other advanced spectral analyses.

关键词： infrared plasmonics germanium(Ge) aluminum(Al) thermal optics longwave infrared(LWIR)multispectral system

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Modelling of phosphorus accumulation in an aeroponic coriander crop

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International Journal of Agricultural and Biological engineering 2022年第6期15卷 73-79页

作者： Alejandro Rincón Santamaría john e.Candelo-Becerra Fredy e.Hoyos Velasco Grupo de Investigación en Desarrollos Tecnológicos y Ambientales-GIDTA Facultad de Ingeniería y ArquitecturaUniversidad Católica de Manizales170002 ManizalesColombia Grupo de Investigación en Microbiología y Biotecnología Agroindustrial-GIMIBAG Instituto de Investigación en Microbiología y Biotecnología AgroindustrialFacultad de Ciencias de la SaludUniversidad Católica de Manizales170002 ManizalesColombia Department of electrical energy and Automation Faculty of MinesUniversidad Nacional de ColombiaSede MedellínMedellín 050041AntioquiaColombia

A model was developed for phosphorus(P)concentration over time in a closed aeroponic coriander *** addition,the setting and starting up of the soilless culture is described,and the measurements of electrical conductivity(eC),pH and concentration of major ions in the mixing tank are *** using mass balance principles,the dynamics of the nutrient concentration in the mixing tank and in the drainage solution are *** series of continuous stirred tank reactors are considered for the flow structure,using a power law relationship to represent the rate of nutrient removal,considering water volume *** concentration measurements were used for model fitting,and the resulting simulation is in good agreement with data.

关键词： aeroponic culture hydroponics soilless culture nutrient modelling Coriander sativum

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Tolerance to individual and joint effects of arsenic and Bacillus thuringiensis subsp, israelensis or Lysinibacillus sphaericus in Culex mosquitoes

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Insect Science 2014年第4期21卷 477-485页

作者： Christina L. Mogren William e. Walton john T. Trumble Department of entomology University of California Riverside CA 92521 USA

Arsenic contamination of global water supplies has come to the forefront in policy decisions in recent decades. However, the effects of arsenic on lower trophic levels of insects inhabiting contaminated ecosystems are not well understood. One approach to document both acute and sublethal effects of toxicants like arsenic is to assay them in combination with microbial pathogens to evaluate shifts in survival curves of the test organisms. Larvae of Culex quinquefasciatus and Culex tarsalis were reared in water containing 0 or 1 000μg/L of arsenate or arsenite. Fourth instars were then exposed to a range of doses of Bacillus thuringiensis subsp, israelensis （Bti） or Lysinibacillus sphaericus （Ls）, with shifts in lethal concentrations determined. Arsenic accumulation in 4th instars was also quantified, and a relative growth index （RGI） calculated for the treatments and compared to controls. Larvae of both species accumulated between 4 447 ± 169 ng As/g and 6 983 4- 367 ng As/g, though RGI values indicated accumulation did not affect growth and development. In all cases, the LC50＇s and LC90＇s of Cx. quinquefasciatus exposed jointly with arsenic and Bti/Ls were higher than Cx. tarsafis. Cx. tarsafis reared in arsenite showed a significant reduction in their Bti LC90 values compared to the control, indicating a sublethal effect of Bti. When exposed jointly with Ls, arsenite was more toxic than arsenate in Cx. tarsalis. Overall, these results indicate tolerance of these Culex species to arsenic exposures, and why this may occur is discussed.

关键词： arsenate arsenite Bsph Bti Culex tarsalis Culex quinquefasciatus

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Polarization variability arising from clumps in the winds of Wolf-Rayet stars

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 558-576页

作者： Qing-Kang Li Joseph e Cassinelli john C. Brown Richard Ignace Department of Astronomy Beijing Normal University Beijing 100875 China Department of Astronomy University of Wisconsin-Madison 53711 USA Department of Physics and Astronomy University of Glasgow Glasgow G12 8QQ Scotland UK Department of Physics and Astronomy Eastern Tennessee State University USA

Polarimetric and photometric variability of Wolf-Rayet （WR） stars as caused by clumps in the winds is revisited. In our model, which is improved from Li et al., radial expansion of the thickness is accounted for, but we retain dependence on the β velocity law and stellar occultation effects. We again search for parameters that can yield results consistent with observations in regards to the mean polarization p, the ratio R = σp/σphot of polarimetric to photometric variability and the volume filling factor fV. Clump generation and spatial distribution are randomized by the Monte Carlo method so as to produce clumps which are, in the mean, distributed uniformly in space and have time intervals that obey a Gaussian distribution. The generated clumps move radially outward with a velocity law determined by a β index, and the angular size of clumps is assumed to be fixed. By fitting the observed σp/σphot and the volume filling factor fv, clump velocity taw index β （- 2） and clump ejection rate .N （- 1） are inferred, and are found to be well constrained. In addition, the subpeak features of broad emission lines seem to support the clump ejection rate. Meanwhile, the fraction of total mass loss rate that is contained in clumps is obtained by fitting observed polarization. We conclude that this picture of the clumps＇ properties produces a valuable diagnostic of WR wind structure.

关键词： stars mass loss -- stars Wolf-Rayet -- stars winds, outflows

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Fructose-sorbitol ingestion provokes gastrointestinal symptoms in patients with eating disorders

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World Journal of Gastroenterology 2009年第42期15卷 5295-5299页

作者： Noel Friesen Ross D Hansen Suzanne F Abraham john e Kellow Department of Obstetrics and Gynaecology Royal North Shore HospitalUniversity of SydneySydney 2065Australia Department of Gastroenterology Royal North Shore HospitalUniversity of SydneySydney 2065Australia

AIM:To evaluate gastrointestinal(GI) symptoms and breath hydrogen responses to oral fructose-sorbitol(F-S) and glucose challenges in eating disorder(eD) ***:GI symptoms and hydrogen breath concentration were monitored in 26 female eD inpatients for 3 h,following ingestion of 50 g glucose on one day,and 25 g fructose/5 g sorbitol on the next day,after an overnight fast on each *** to F-S were compared to those of 20 asymptomatic healthy ***:F-S provoked GI symptoms in 15 eD patients and one healthy control(P eD vs control) .Only one eD patient displayed symptom provocation to glucose(P esponse) .A greater symptom response was observed in eD patients with a body mass index(BMI) ≤ 17.5 kg/m 2 compared to those with a BMI > 17.5 kg/m 2(P ere were no differences in psychological scores,prevalence of functional GI disorders or breath hydrogen responses between patients with and without an F-S ***:F-S,but not glucose,provokes GI symptoms in eD patients,predominantly those with low *** findings are important in the dietary management of eD patients.

关键词： Fructose Sorbitol Malabsorption syndromes Functional gastrointestinal disorders eating disorders Underweight

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Treatment of hemorrhoids: A survey of surgical practice in Australia and New Zealand

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World Journal of Clinical Cases 2019年第22期7卷 3742-3750页

作者： George e Fowler Javariah Siddiqui Assad Zahid Christopher john Young Department of Colorectal Surgery Royal Devon and Exeter NHS Foundation TrustExeter EX25DWUnited Kingdom Department of Colorectal Surgery Royal Prince Alfred HospitalNewtown 2042NSWAustralia

BACKGROUND Hemorrhoidal disease is the most common anorectal *** can be classified as external or internal,according to their relation to the dentate *** hemorrhoids originate below the dentate line and are managed conservatively unless the patient cannot keep the perianal region clean,or they cause significant *** hemorrhoids originate above the dentate line and can be managed according to the graded degree of prolapse,as described by ***,low-grade internal hemorrhoids are effectively treated conservatively,by non-operative measures,while high-grade internal hemorrhoids warrant procedural *** To determine the application of clinical practice guidelines for the current management of hemorrhoids and colorectal surgeon consensus in Australia and New *** An online survey was distributed to 206 colorectal surgeons in Australia and New Zealand using 17 guideline-based hypothetical clinical *** There were 82 respondents(40%)to 17 guideline-based ***(53%)reached consensus,of which only 1(6%)disagreed with the *** was based on low quality evidence for the management of acutely thrombosed external *** were 8 scenarios which showed community equipoise(47%)and they were equally divided for agreeing or disagreeing with the *** topics were based on low and moderate levels of *** included the initial management of grade I internal hemorrhoids,grade III internal hemorrhoids when initial management had failed and the patient had recognised risks factors for septic complications;and finally,the decision-making when considering patient preferences,including a prompt return to work,or minimal post-operative *** Although there are areas of consensus in the management of hemorrhoids,there are many areas of community equipoise which would benefit from further research.

关键词： Hemorrhoids Clinical practice guidelines Survey Consensus

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Simulating hydraulic fracturing processes in laboratory-scale geological media using three-dimensional TOUGH-RBSN

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Journal of Rock Mechanics and Geotechnical engineering 2018年第6期10卷 1102-1111页

作者： Daisuke Asahina Pengzhi Pan Kimikazu Tsusaka Mikio Takeda john e.Bolander Geological Survey of Japan IbarakiJapan State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China INPeX Corporation TokyoJapan University of California DavisUSA

In this context, recent developments in the coupled three-dimensional(3 D) hydro-mechanical(HM)simulation tool TOUGH-RBSN are presented. This tool is used to model hydraulic fracture in geological media, as observed in laboratory-scale tests. The TOUGH-RBSN simulator is based on the effective linking of two numerical methods: TOUGH2, a finite volume method for simulating mass transport within a permeable medium; and a lattice model based on the rigid-body-spring network(RBSN) concept. The method relies on a Voronoi-based discretization technique that can represent fracture development within a permeable rock matrix. The simulator provides two-way coupling of HM processes, including fluid pressure-induced fracture and fracture-assisted flow. We first present the basic capabilities of the modeling approach using two example applications, i.e. permeability evolution under compression deformation, and analyses of a static fracturing simulation. Thereafter, the model is used to simulate laboratory tests of hydraulic fracturing in granite. In most respects, the simulation results meet expectations with respect to permeability evolution and fracturing patterns. It can be seen that the evolution of injection pressure associated with the simulated fracture developments is strongly affected by fluid viscosity.

关键词： Hydraulic fracture Crack opening TOUGH Rigid-body-spring network(RBSN) Permeability Injection pressure Fluid viscosity Hydro-mechanical(HM) processes

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