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Effects of shifting cultivation on biological and biochemical characteristics of soil microorganisms in Khagrachari hill district, Bangladesh

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Journal of Forestry Research 2014年第3期25卷 689-694页

作者： sohag miah s.m. sirajul haque Wahida s.m. mohammad mosharraf Hossain Institute of Forestry and Environmental sciences University of Chittagong Department of microbiology University of Chittagong Department of Applied Physics Graduate School of Engineering Osaka University

We collected soil s.m.les from two representative sites at Aatmile of Khagarachari hill district in Chittagong Hill Tracts. One of the sites was under shifting cultivation and the other an adjacent 13-year old teak plantation. Both sites were in the s.m. physiographic condition and s.m. aspect with parable soil type, which enabled us to measure the effects of shifting cultivation on soil micro-flora. We studied soil phys-ico-chemical properties and the biochemical and biological properties of soil microbes. moisture and organic matter content as well as fungi and bacterial populations, both in surface and subsurface soils, were signifi-cantly （p≤0.001） lower in shifting cultivated soils compared to soils not under shifting cultivation, i.e. the teak plantation site. The most abundant bacteria in surface （0-10 cm） and sub-surface （10-20 cm） soils under shifting cultivation were Pseudomonas diminuta and shigella, respec-tively, while in corresponding soil layers of teak plantation, predominant microbes were Bacillus firmus （0-10 cm） and Xanthomonas （10-20 cm）. The microbial population differences cannot be explained by soil texture differences because of the textural s.m.larity in soils from the two sites but could be related to the significantly lower moisture and organic mat-ter contents in soils under shifting cultivation.

关键词： shifting cultivation soil biological properties soil biochemical properties soil microflora Chittagong Hill Tracts

Clear felling and burning effects on soil nitrogen transforming bacteria and actinomycetes population in Chittagong University campus, Bangladesh

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Journal of Forestry Research 2012年第1期23卷 123-130页

作者： s.m. sirajul haque Rahima Ferdoshi sohag miah m. Nural Anwar Institute of Forestry and Environmental sciences University of Chittagong Chittagong-4331 Bangladesh Department of microbiology University of Chittagong Chittagong-4331 Bangladesh

The effect of forests clear felling and associated burning on the population of soil nitrogen transforming bacteria and actinomycetes are reported at three pair sites of Chittagong University campus, Bangla- desh in monsoon tropical climate. Clear felled area or burnt site and 15-21 year mixed plantation of native and exotic species, situated side by side on low hill having Typic Dystrochrepts soil was represented at each pair site. At all the three pair sites, clear felled area or burnt site showed very significantly （p~_0.001） lower population of actinomycetes, Rhizobium, Nitros.m.nas, Nitrobacter and ammonifying as well as deni- trifying bacteria compared to their adjacent mixed plantation. From en- vironmental consideration, this finding has implication in managing natural ecosystem.

关键词： Nitrogen transforming bacteria actinomycetes forest clearfelling effects burning effects soil microorganisms Chittagong HillTracts

Effect of shifting cultivation on soil physical and chemical properties in Bandarban hill district, Bangladesh

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Journal of Forestry Research 2013年第4期24卷 791-795页

作者： Khandakar showkat Osman m.Jashimuddin s.m.sirajul haque sohag miah Institute of Forestry and Environmental sciences University of Chittagong

This study reports the effects of shifting cultivation at slashing stage on soil physicochemical properties at Bandarban sadar Upazila in Chittagong Hill Tracts of Bangladesh. At this initial stage of shifting cultivation no general trend was found for moisture content, maximum water holding capacity, field capacity, dry and moist bulk density, parti- cle density for s.m. chemical properties between shifting cultivated land and forest having s.m.lar soil texture. Organic matter was significantly 0.05） lower in 1-year and 3-year shifting cultivated lands and higher in 2-year shifting cultivation than in adjacent natural forest. significant differences were also found for total N, exchangeable Ca, mg and K and in CEC as well as for available P. slashed area showed higher soil pH. Deterioration in land quality starts from burning of slashing materials and continues through subsequent stages of shifting cultivation.

关键词： Chittagong Hill Tracts natural forest shifting cultivation soil properties

shifting cultivation effects on creek water quality around Barkal Upazila in Chittagong Hill Tracts,Bangladesh

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Journal of Forestry Research 2012年第4期23卷 623-630页

作者： shyamal Karmakar s.m.sirajul haque m.mozaffar Hossain sohag miah Institute of Forestry and Environmental sciences University of ChittagongChittagong 4331Bangladesh

Abstract： We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently s.m.lar small neighboring watersheds, each of 3 to 5 ha, at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh. Concentrations of 5042- and K＋, and pH in creek water were lower, and NO3-N and Na＋ concentrations were higher in shifting-cultivation land compared to land with either plantation or natu- ral forest or a combination of these cover types. shifting cultivation effects on s.m. water quality parameters were not significant due to change in land cover of the watershed between two s.m.ling periods either through introduction of planted tree species or naturally regenerated vegetation. Conductivity and concentrations of HCO3- PO43-, Ca2-- and mg2＋ in creek water showed no definite trend between shifting cultivation and the other land cover types. At one area near the Forest Range Office of Barkal, creek water pH was 5.8 under land cover with a com- bination of shifting cultivation and plantation. At this area Na~ concentra- tion in shitting-cultivation land ranged from 32.33 to 33.00 mg-L＂ and in vegetated area from 25.00 to 30.50 mg.L-1 in 2007. At another area, Chaliatali Chara, sO42 concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg-L-1, lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg.L-1 in 2007. s042-concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg.L^-1 and in the vegetated area from 1.37 to 3.50 mg-L^-1 in 2008.

关键词： shifting cultivation Creek water quality Chittagong Hill Tracts Riparian vegetation Land cover Bangladesh

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Water quality of Kaptai reservoir in Chittagong Hill Tracts of Bangladesh

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Journal of Forestry Research 2011年第1期22卷 87-92页

作者： shyamal Karmakar s. m. sirajul haque m. mozaffar Hossain m. shafiq Institute of Forestry and Environmental sciences University of Chittagong Chittagong Bangladesh 4331 Department of soil science University of Chittagong Chittagong Bangladesh 4331

A study was conducted in Kaptai reservoir, one of the largest man-made freshwater lakes of south-east Asia, to determine present status of water quality and its suitability for fishing and other uses. Water s.m.lings were from middle part of the reservoir at 0.2 and 0.8 fractional depths at five different locations from upstream to downstream viz. Burburichara, maichchari, subolong, Basanthakum, and Rangamati. Water analyses show that concentrations of NO3-N, K＋ and total P, and suspended solid at all the s.m.ling stations were beyond the recommended values for fish culture. Concentrations of Na^＋, Ca^2＋, mg^2＋, sO4^2-, Cl^-, total dissolved solid （TDs）, dissolved oxygen （DO） and chemical oxygen demand （COD） were within the standards for aquaculture. Concentrations of NO3-N, sO4^2-, K＋ and total P showed no definite trend with depths, locations as well as rainy and dry seasons. Water pH, conductivity, Na^＋ and HCO3- contents were lower in rainy season, and DO and COD higher at almost all the locations in both the depths, compared with dry season. Total solids and concentrations of TDs, DO, COD, Ca^2＋, mg^2＋ and Na^＋ were higher in upstream and decreased gradually towards downstream in the reservoir. Concentrations of DO and Ca2＋ and pH were higher and mg2＋ less at 0.2-fractional depth than those at 0.8-fractional depth at almost all the locations. The reservoir is in mesotrophic condition containing high concentration of NO3-N and total P, in alarming status with the presence of excessive suspended solids from urban pollution around the town. It is necessary to adopt measures for protecting water quality in the reservoir due to such deteriorations.

关键词： Karnaphuli river lake water quality Chittagong Hill Tract

Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.s.m.THI s.ANTONY CARLA Department of mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros.m.ñé Laia Just-Borràs.m.rta Balanyà-segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina silvera-s.m.n manel m.santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we s.m.arize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur s.m.ltaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

modelling, parameter estimation and asses.m.nt of partial shading conditions of photovoltaic modules

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Journal of modern Power systems and Clean Energy 2019年第1期7卷 55-64页

作者： s.LYDEN m.E.haque school of Engineering University of Tasmania school of Engineering Deakin University

This paper proposes a method for assessing the effect that different features of partial shading conditions(PsC) may have on the operation of a photovoltaic(PV)*** studies, based on an experimentally validated model of a PV system, are used to assess the influence of *** classifications of PsC are defined based on the timescale of their influence on the irradiance experienced by the PV module and the relative location of the voltage at which the global maximum power point occurs is *** case studies are presented to illustrate the application of the proposed PsC asses.m.nt *** results have implications for the design of future maximum power point tracking methods.

关键词： Photovoltaic modelling Partial shading maximum power point