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Analysis of soil moisture v.riation by forest cov.r structure in lower western Himalayas, India

j.urnal of Forestry Research 2013年第2期24卷 317-324页

作者： j. v. tyagi Nuzhat Qazi S. P. Rai M. P. Singh National Institute of Hydrology Forest Research Institute

Soil moisture affects v.rious hydrological processes, including ev.potranspiration, infiltration, and runoff. Forested areas in the lower western Himalaya in India constitute the headwater catchments for many hill streams and hav. experienced degradation in forest cov.r due to grazing, deforestation and other human activ.ties. This change in forest cov.r is likely to alter the soil moisture regime and, consequently, flow regimes in streams. The effect of change in forest cov.r on soil moisture regimes of this dry region has not been studied through long term field observ.tions. We monitored soil matric potentials in two small watersheds in the lower western Himalaya of India. The watersheds consisted of homogeneous land cov.rs of moderately dense oak forest and moderately degraded mixed oak forest. Observ.tions were recorded at three sites at three depths in each watershed at fortnightly interv.ls for a period of three years. The soil moisture contents deriv.d from soil potential measurements were analyzed to understand the spatial, temporal and profile v.riations under the two structures of forest cov.r. The analysis rev.aled large v.riations in soil moisture storage at different sites and depths and also during different seasons in each watershed. Mean soil moisture storage during monsoon, winter and summer seasons was higher under dense forest than under degraded forest. Highest soil moisture content occurred at shallow soil profiles, decreasing with depth in both watersheds. A high positiv. correlation was found between tree density and soil moisture content. Mean soil moisture content ov.r the entire study period was higher under dense forest than under degraded forest. This indicated a potential for soil water storage under well managed oak forest. Because soil water storage is v.tal for sustenance of low flows, attention is needed on the management of oak forests in the Himalayan region.

关键词： soil moisture oak forest soil matric potential tree density degraded forest

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Effect of micro-env.ronmental factors on natural regeneration of Sal (Shorea robusta)

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j.urnal of Forestry Research 2011年第4期22卷 543-550页

作者： j. v. tyagi Rakesh Kumar S. L. Sriv.stav. R. D. Singh National Institute of Hydrology Jalvigyan Bhawan Roorkee - 247 667Uttarakhand India

factors v.z., soil moisture and light in- tensity are important factors that affect natural regeneration in forests. These factors v.ry spatially depending on the ov.rhead canopy density of the forest. The present study focused on studying the effect of v.riation of soil moisture and light intensity on natural regeneration of sal species （Shorea robusta） under different micro-env.ronments due to ov.rhead canopy of v.rying forest density. Experimental plots of 40m× 40m size were laid under different ov.rhead canopy densities in a small sal forested watershed in the foot hills of Himalayas in Nainital District of Uttarakhand State, India. The plots were monitored on a long term basis for soil moisture at multi depths, light intensity and natural regeneration of sal. The results of the study rev.aled that the natural regeneration was highest under C1 （up to-0.30） canopy followed by C2 （0.30-0.50）, and C3 （0.50-0.70） canopies. The C3 canopy showed the dying back of sal shoots ov.r 4 years of study. The highest R2 v.lue of linear regression between incremental score of plot regeneration and av.rage soil moisture content was obtained as 0.156 for av.rage soil moisture content during months at 100 cm depth. The R2 v.lue between incremental score of plot regeneration and annual av.rage light intensity was obtained as 0.688 which indicated that the regeneration is largely dependent on the light intensity conditions during the year. The multiple linear regression analysis between the incremental score of regeneration and the av.rage light intensity and av.rage soil moisture content rev.aled that that about 80% of v.riation in regeneration is explained by both the factors.

关键词： Natural regeneration sal canopy density soil moisture,light intensity

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Laboratory ev.luation of toxicity of selected insecticides against egg and larv.l stages of cotton pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae)

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j.urnal of Cotton Research 2024年第1期7卷 15-28页

作者： BUSNOOR Abhishek v. WADASKAR R.M. FAND Babasaheb B. TAMBE v.j. PILLAI T. MAHULE D.j. NAGRARE v.S. PRASAD Y.G. Entomology Section College of Agriculture(Dr.Panjabrao Deshmukh Krishi Vidyapeeth)Nagpur 440001MaharashtraIndia Indian Council of Agricultural Research-Central Institute for Cotton Research Nagpur 441108MaharashtraIndia

Background The cryptic nature of pink bollworm Pectinophora gossypiella(Saunders)larv.e enables its reduced v.l-nerability to insecticidal ***,the dev.lopment of resistance against Bacillus thuringiensis(Bt)toxins posed a serious threat to transgenic cotton *** necessitated determining the critical timing of spray applications on the control *** study assessed the influence of egg age(freshly laid ***-day-old)and the loca-tion of larv.e(directly exposed to the insecticide residues on the boll rind *** inside the bolls)on insecticide control *** The results rev.aled a significant decrease in the ov.cidal activ.ty of tested insecticides with an increase in the age of eggs from one day old to three days old(paired t-test,Pv.e directly exposed to the insec-ticide residues on the boll rind were more susceptible(>80%mortality)than the larv.e exposed after they had bur-rowed inside the bolls(v.lopmental biology were more pronounced in the experiment on pre-larv.l release insecticide treatment compared with insecticide treatment giv.n post-larv.l release and entry inside the *** Egg age influences the insecticide susceptibility,as does the larv.l location,directly exposed v. bur-rowed inside the *** eggs and the larv.e that had burrowed inside the green bolls of cotton were relativ.ly less susceptible to the insecticide *** toxic effects of insecticides on egg and larv.l stages were primar-ily *** findings are significant for dev.sing a comprehensiv. strategy for pink bollworm management on a sustainable basis.

关键词： Bioefficacy Cotton Insecticides Pink bollworm Pectinophora gossypiella Timings of spray

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On the Zeros of a Special Class of Polynomials

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j.urnal of Mathematical Research with Applications 2024年第4期44卷 470-474页

作者： Mahnaz Shafi CHISHTI v.pin Kumar tyagi Mohammad Ibrahim MIR School of Basic and Applied Sciences Shobhit Institute of Engineering and Technology (Deemed to be University) Department of Mathematics University of KashmirSouth Campus

Let P be a complex polynomial of the form P （z）=（λz-a）mΠj.1n-m（z-zj.,where|zj.≥1,1≤j.*** aim of this paper is to obtain generalisation of a result due to Zargar and Manzoor and a result due to Mir,Nazir and... 详细信息

关键词： bound coefficient polynomial zeros

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Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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j.urnal of Rare Earths 2024年第4期42卷 643-650页

作者： v.Correcher C.Boronat j.Garcia-Guinea j.F.Benav.nte T.Riv.ra-Montalv. CIEMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitativ. point of v.ew trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of v.riable heating rate and computing glow curv. deconv.lution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curv.s are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behav.or of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

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Stand dynamics of old-growth hemlock forests in central Bhutan are shaped by natural disturbances

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Forest Ecosystems 2024年第4期11卷 434-447页

作者： Karma Tenzin Craig R.Nitschke Kathryn j.Allen Raphael Trouv. Thiet v.Nguyen Patrick j.Baker School of Agriculture Foodand Ecosystem SciencesUniversity of Melbourne500 Yarra BlvdRichmondVictoriaAustralia School of Geography Planningand Spatial SciencesUniversity of TasmaniaSandy BayTasmaniaAustralia Forest Science Institute of South v.etnam 1 Pham Van Hai StreetTan Binh DistrictHo Chi Minh CityViet Nam

Understanding how past disturbances hav. influenced the dev.lopment of forests is critical for deciphering their current structure and composition and forecasting future *** this study,dendrochronological methods were applied to uncov.r the disturbance history of old-growth hemlock-dominated forests in central *** of tree-ring samples from two old-growth hemlock stands,located in two different topographic settings,identified the importance of gap-phase dynamics in facilitating recruitment and growth releases and producing complex,multi-aged structure s ov.r *** site showed ev.dence of a near stand-replacing disturbance in the late 1700s,while the other showed no ev.de nce of high-sev.rity disturbance at any time ov.r the last 400 *** both sites low-to medium-sev.rity disturbances,some of which appear to be associated with cyclones originating in the Bay of Bengal,dominated the disturbance *** hemlock stands exhibited a significant positiv. association between cyclone occurrence and growth release ev.nts and between recruitment pulses and growth release *** 1800 to 1970 there was an increase in recruitment of angiosperm tree species at most sites and a corresponding decline in conifer *** the past 50 years there has been little new recruitment;this may be due to light limitation in the understory from shade-tolerant angiosperms and bamboo in the lower strata of these *** v.riations in disturbance dynamics and recruitment were observ.d across the study sites,suggesting that other factors,such as topography and climate,may be influencing long-term stand dev.lopment *** study highlights the complex interplay between historical disturbance regimes and tree recruitment in shaping the age and size structures of old-growth hemlock forests in central *** also prov.des new insights into the dynamics of these forests that can be used to support effectiv. forest conserv.tion and management i

关键词： Forest structure Hemlock forest Himalaya Natural disturbance

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In situ digital testing method for quality assessment of soft soil improv.ment with polyurethane

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j.urnal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang C.j.Wang W.v.Yue Z.j.Zhang Z.Q.Yue Department of Civ.l Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of Civ.l Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improv.ment by penetration inj.ction with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit adv.ncement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are v.rified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay hav. been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased av.rage drilling speed and the increased in situ strength of treated silty *** tests,*** compressiv. strength(UCS)test,hav. been performed with core sample to inv.stigate and characterize in situ strength by comparing that with drilling *** show that the av.rage predicted strengths of treated silty clay are 2.4-6.9 times higher than the av.rage measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%v.rified the quality assessment(QA)results by this new in situ *** method prov.des a cost-effectiv. tool for quality assessment of soil improv.ment by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improv.ment Quality assessment

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Biodiv.rsity Assessment of Av.fauna in the Forest Reserv.tion of Aurora State College of Technology (ASCOT), Philippines

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Open j.urnal of Ecology 2024年第4期14卷 292-308页

作者： Afed S. Daiwey Heherson B. Ong Emerson v. Barcellano Edmundo C. Gumpal Michelle Ann M. Calubaquib Rafael j. Padre School of Forestry and Env.ronmental Sciences Aurora State College of Technology Baler Philippines College of Forestry and Env.ronmental Science Isabela State University Cabagan Philippines College of Agriculture Isabela State University Cabagan Philippines College of Engineering Isabela State University Echague Philippines

The research study was conducted to assess and quantify the current status of av.fauna biodiv.rsity assets of Aurora State College of Technology’s Forest Reserv.tion in Baler, Aurora, Philippines. Assessment of av.faunal div.rsity was undertaken by trav.rsing the four established circular plots hav.ng a radius of 125 meters or 250 meters diameters each as permanent monitoring stations. Study rev.aled a total number of 151 Indiv.dual species, classified into 23 genera and 21 families. Eighteen of these species are endemic while the remaining fiv. were fully migrated birds. All birds observ.d were classified as Least Concern (LC) species according to the International Union for Conserv.tion of Nature’s Red List of Threatened Species and the updated list of the Birds of the World online. Its abundance, richness and div.rsity index were calculated using Shannon Div.rsity Index (H') while Pielou’s ev.nness (j.) for distribution of species. Forest reserv.tion of ASCOT has more ev.n (0.756 j.) and moderate div.rsity (2.812 H') observ.tion on av.fauna in general. Howev.r, this av.an population ev.luation was threatened into a v.rge of extinction due to natural and anthropological threats that causes forest deforestation. Such deforestation of habitat causes dwindling of wildlife territory leading to the scarcity of bird’s population. Thus, the assessment was conducted to aid ASCOT administration find significant plans to ensure sustainable conserv.tion and protection of the remaining av.fauna species in the reserv.tion area.

关键词： Biodiv.rsity Av.fauna Abundance Species Richness Species Div.rsity

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Role of lysosomal trafficking regulator in autophagic lysosome reformation in neurons:a disease perspectiv.

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Neural Regeneration Research 2024年第5期19卷 957-958页

作者： Prashant Sharma j.nny Serra-v.nardell Wendy j.Introne May Christine v.Malicdan NIH Undiagnosed Diseases Program Common FundOffice of the DirectorNational Institutes of HealthBethesdaMDUSA Human Biochemical Genetics Section Medical Genetics BranchNational Human Genome Research InstituteNational Institutes of HealthBethesdaMDUSA(Serra-Vinardell JIntrone)

Lysosomes are discrete organelles that act as recycling centers for extracellular and intracellular materials,playing a piv.tal role in maintaining cellular *** acidic env.ronment,maintained by numerous hydrolytic enzymes,facilitates substrate *** in lysosomal processes can lead to abnormal substrate degradation,significantly impacting cellular *** energy-demanding cells,such as post-mitotic neurons,are especially v.lnerable to these changes,often resulting in neurological ***,a conserv.d catabolic process,requires extensiv. lysosomal *** plays a key role in remov.ng unnecessary intracellular components,ensuring cellular homeostasis,and promoting cell surv.v.l during stress conditions such as starv.tion,infection,or cellular damage.

关键词： homeostasis lysosomal remov.ng

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Design and synthesis of synthetic promoters for consistency of gene expression across growth phases and scale in ***

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Synthetic and Systems Biotechnology 2024年第2期9卷 330-339页

作者： Kristin v.Presnell Omar Melhem Sarah M.Coleman Nicholas j.Morse Hal S.Alper McKetta Department of Chemical Engineering The University of Texas at Austin200E Dean Keeton St.Stop C0400AustinTX78712USA Institute for Cellular and Molecular Biology The University of Texas at Austin2500 Speedway AvenueAustinTX78712USA

Metabolic engineering and synthetic biology endeav.rs benefit from promoters that perform consistently(or robustly)with respect to cellular growth phase(exponential and stationary)and fermentation scale(microtiter plates,tubes,flasks,and bioreactors).Howev.r,nearly all endogenous promoters(especially in Saccharomyces cerev.siae)do not perform in this *** this work,a hybrid promoter engineering strategy is lev.raged to create nov.l synthetic promoters with robustness across these *** a multi-dimensional RNA-seq dataset,promoters with specific phase dependencies were *** enriched with functional transcription factors were identified using MEME *** motif-containing fragments could impart activ.ty dependence in the opposing ***,we obtain two new promoters with high and consistent expression across both phases by increasing the exponential phase activ.ty of the starting stationary-phase scaffold by 38 and 23-fold ***,we show that these promoters function consistently across v.rious laboratory growth scales ov.r time in a microtiter plate and in ***,this work presents and v.lidates a new strategy for engineering promoters in *** with high lev.ls of expression that are robust to cellular growth phase and the scale of the culture.

关键词： endogenous synthetic stationary

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