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Feasibility of Micro-Hydro Power for Rural Electrification in Bangladesh:A Case Study from the Chittagong Hill Tracts
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作者 Ratan Kumar Das Abhijit Date +1 位作者 Harun Chowdhury Hamed Hassan 《Energy Engineering》 2025年第12期4815-4835,共21页
Bangladesh has achieved notable progress in expanding electricity access nationwide.Nonetheless,remote and topographically challenging regions such as the Chittagong Hill Tracts(CHT)continue to face coverage gaps due ... Bangladesh has achieved notable progress in expanding electricity access nationwide.Nonetheless,remote and topographically challenging regions such as the Chittagong Hill Tracts(CHT)continue to face coverage gaps due to grid extension difficulties.This research investigates the technical feasibility of micro-hydro power(MHP)systems as viable off-grid solutions for rural electrification in CHT.Field surveys conducted across various sites assessed available head and flow rates using GPS-based elevation measurements and portable flowmeters.Seasonal fluctuations were factored into the analysis to ensure year-round operational viability.The study involved estimating power output,selecting appropriate turbine types based on head-flow data,and proposing preliminary plant configurations.Results identify multiple locations with adequate head(2.5 to 10.4 m)and flow rates(0.10 to 0.35 m3/s),capable of generating between 1.5 and 16.5 kW,sufficient for essential rural applications.Based on site-specific head and discharge characteristics,Kaplan and Francis turbines were identified as the most suitable configurations,offering high efficiency for the medium-flow,low-to-medium head environments typical of the studied regions.Despite inherent technical potential,challenges such as seasonal variability,infrastructure complexities,and policy deficiencies remain.This investigation addresses a critical knowledge gap in local renewable energy planning.It offers a data-driven foundation for pilot projects and community-scale electrification initiatives in Bangladesh’s remote mountainous areas. 展开更多
关键词 Micro-hydro power(MHP) rural electrification Chittagong Hill tracts(CHT) renewable energy feasibility head-flow assessment off-grid energy solutions
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Comparative evaluation of physical properties in soils of orange orchard and bushy forest in chittagong hill tracts, Banglandesh 被引量:4
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作者 Mohammad Shaheed Hossain Chowdhury Md. Abdul Halim +3 位作者 Shampa Biswas S. M. Sirajul Haque Nur Muhammed Masao Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期245-248,共4页
The physical properties of soil on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill Tracts (CHTs) were evaluated and compared with those of bushy hill forests. Soil sam... The physical properties of soil on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill Tracts (CHTs) were evaluated and compared with those of bushy hill forests. Soil samples were collected from three different depths (0-5 cm, 5-15 cm and 15-30 cm), digging three profiles in each land use for determining moisture content, organic matter content and particle density. Maximum water holding capacity, field capacity, dry and moist bulk density and porosity were determined only for the surface soils. Moisture content at all the soil depths was significantly higher (p≤ 0.05) in orange orchard than in forest on both the slopes. Orange orchard contained lower mean soil organic matter than forest on 55% slope, while it contained higher values on 35% slope compared to forest. The highest value of the above two properties was found at surface soil in both the land uses on both the slopes, decreasing with the increase of soil depth. On both the slopes maximum water holding capacity and porosity of surface soil and particle density at all soil depths were lower in orange orchard compared to those in forest. Field capacity values of surface soil did not show consistency in trend for the differences between the two land uses on both the slopes. Bulk density value of moist and dry surface soil was higher in orange orchard than in forest on both the hill slopes. 展开更多
关键词 Orange orchard Bushy forests Physical property Slope Chittagong Hill tracts
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Study on soils under shifting cultivation and other land use categories in Chittagong Hill Tracts, Bangladesh 被引量:3
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作者 Alake Biswas M.Alamgir +1 位作者 S.M.S.Haque K.T.Osman 《Journal of Forestry Research》 CAS CSCD 2012年第2期261-265,共5页
Soil samples were collected and analyzed from 25 sites of three hilly regions (Rangamati, Banderban and Khagrachari) for an understanding of the impact of denudation and land use on soils in Chittagong Hill Tracts, ... Soil samples were collected and analyzed from 25 sites of three hilly regions (Rangamati, Banderban and Khagrachari) for an understanding of the impact of denudation and land use on soils in Chittagong Hill Tracts, Bangladesh. There were natural forests, bushy land, slashed sites, slashed and burnt sites, and the sites prepared for shifting cultivation, one year after shifting cultivation and two years after shifting cultivation. The soils were generally yellowish brown to reddish brown, sandy to sandy clay loam, strongly acid, and well to excessively drained on steep slopes with considerable variation among the sites and land use categories. Bulk density was the highest in sites of one year after shifting cultivation (1.52 g·cm^-3) and the lowest in forested sites (1.38 g·cm^-3). Water holding capacities were, however, statistically similar in all sites. Organic carbon varied from 0.54% (slashed and burnt sites) to 1.55% (forested sites) and total N ranged from 0.05% (shifting cultivation for one year) to 0.13% (forested sites). Available phosphorus (Bray & Kurtz-2 P) was the maximum in forested sites (12.32 mg·kg^-l), and it did not differ significantly in other sites. Contents of available Ca, Mg and K were also higher in the bushy lands and forested sites than cleared and shifting cultivated sites. 展开更多
关键词 Chittagong Hill tracts BANGLADESH DENUDATION shifting cultivation soil degradation
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Community ecology and spatial distribution of trees in a tropical wet evergreen forest in Kaptai national park in Chittagong Hill Tracts, Bangladesh 被引量:2
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作者 S. M. Feroz Md Rabiul Alam +1 位作者 Prokash Das Abdullah Al Mamun 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期311-318,共8页
We investigated the floristic composition, woody species diversity and spatial distribution of trees in a tropical wet evergreen forest in Kaptai national park in Chittagong Hill Tracks, Bangladesh. We recorded 25 fam... We investigated the floristic composition, woody species diversity and spatial distribution of trees in a tropical wet evergreen forest in Kaptai national park in Chittagong Hill Tracks, Bangladesh. We recorded 25 families, 37 genera, 40 species and 1771 woody individuals in a 0.09 ha plot. Euphorbiaceae and Moraceae were the most species- rich families, and Castanopsis, Ficus and Terminaliawere the most species-rich genera. Bursera serrata Wall. ex Colebr. was the dominant species in terms of highest importance value (13%). Trema orientalis (L.) B1 was typically a light demanding species as it appeared in the top can- opy with only one individual having the seventh highest IV, but had no regeneration. The expected maximum number of species (Smax) was 140, indicating that many species may invade the forest as the Sm~ is greater than the recorded total number of species. The nature of the disappear- ance and appearance of species in the present forest reflects instability of floristic composition. The values of Shannon's index H' and Pielou's index J' (evenness) were 3.36 bit and 0.63, respectively. These values show moderately high species diversity as compared to other subtropical forests in the tropics. In addition, a sample area of 200 m2 in this forest would be sufficient for measuring the diversity indices H" and ,/', whereas the trend of J'may indicate the rate of equality of individuals among the different species decreased with increasing area. The distribu- tion pattern for the total stand was completely random. However, the dominant species showed aggregate distribution for small areas, but random distribution for large areas. The spatial association between species showed that the strongest positive interspecific association occurred between Streblus asper Lour. and Castanea indica Roxh. (09 = 0.51). As a whole, most species were weakly associated with each other, of which 58% species associations were completely negative. The result of cluster analysis showed that species pairs were spatially independent at all or most small clusters; stands of species from all clusters are mosa- ics of complete habitat and pioneer habitat. All patches in this forest community have similar habitat and regeneration niches, which could be a phenomenon for a young growth forest. Thus, the existence of habitat and regeneration niches may be an important factor in the maintenance of diversity in this forest. 展开更多
关键词 Chittagong Hill tracts floristic composition spatial distribution of trees tropical wet evergreen forest woody species diversity
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Shifting cultivation effects on creek water quality around Barkal Upazila in Chittagong Hill Tracts,Bangladesh 被引量:1
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作者 Shyamal Karmakar S.M.Sirajul Haque +1 位作者 M.Mozaffar Hossain Sohag Miah 《Journal of Forestry Research》 CAS CSCD 2012年第4期623-630,共8页
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 similar small neighboring watersheds, each of 3 to 5 ha, at four loca... 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 similar 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 some water quality parameters were not significant due to change in land cover of the watershed between two sampling 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. 展开更多
关键词 Shifting cultivation Creek water quality Chittagong Hill tracts Riparian vegetation Land cover BANGLADESH
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A Fiber Tractography Study of Social-Emotional Related Fiber Tracts in Children and Adolescents with Autism Spectrum Disorder 被引量:5
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作者 Yun Li Hui Fang +7 位作者 Wenming Zheng Lu Qian Yunhua Xiao Qiaorong Wu Chen Chang Chaoyong Xiao Kangkang Chu Xiaoyan Ke 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第6期722-730,共9页
The symptoms of autism spectrum disorder(ASD) have been hypothesized to be caused by changes in brain connectivity. From the clinical perspective, the‘‘disconnectivity'' hypothesis has been used to explain chara... The symptoms of autism spectrum disorder(ASD) have been hypothesized to be caused by changes in brain connectivity. From the clinical perspective, the‘‘disconnectivity'' hypothesis has been used to explain characteristic impairments in ‘‘socio-emotional'' function.Therefore, in this study we compared the facial emotional recognition(FER) feature and the integrity of socialemotional-related white-matter tracts between children and adolescents with high-functioning ASD(HFA) and their typically developing(TD) counterparts. The correlation between the two factors was explored to find out if impairment of the white-matter tracts is the neural basis of social-emotional disorders. Compared with the TD group,FER was significantly impaired and the fractional anisotropy value of the right cingulate fasciculus was increased in the HFA group(P / 0.01). In conclusion, the FER function of children and adolescents with HFA was impaired and the microstructure of the cingulate fasciculus had abnormalities. 展开更多
关键词 Autism spectrum disorder Facial emotional recognition Social-emotional related white matter fiber tracts Diffusion tensor imaging Tractography
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Management of Village Common Forests in the Chittagong Hill Tracts of Bangladesh: Historical Background and Current Issues in Terms of Sustainability 被引量:1
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作者 Mohammed Jashimuddin Makoto Inoue 《Open Journal of Forestry》 2012年第3期121-137,共17页
This study was conducted to investigate the historical management system of village common forests (VCF) in the Chittagong Hill Tracts (CHT) of Bangladesh and observe the current issues related to their sustainability... This study was conducted to investigate the historical management system of village common forests (VCF) in the Chittagong Hill Tracts (CHT) of Bangladesh and observe the current issues related to their sustainability. The study on historical context was based on secondary information to establish the linkages of VCF development and management in the CHT. Field visits to four VCF in the Bandarban Hill Districts were also conducted to cross check the information collected from secondary sources to observe the current status and management pattern of these VCF through semi-structured interviews, group discussion, key-informant interviews and biodiversity assessment. VCF in the CHT undoubtedly play an important role in biodiversity conservation and as well as supporting daily necessities of the community people. We found that VCF still are the source of fuel wood, herbs, roots, bamboo shoots, wild fruits, vines or leaves for cooking or medicinal use necessary to sustain the lives of the indigenous communities in the CHT. Field visits to different VCF show that the VCF are necessarily small in size (57 ha) and around 108 families are dependent on these community managed village forests. A total of 163 plant species from 60 families were also recorded from these VCF including some rare plant and animal species which are not usually found in the reserve forests and the un-classed state forests due to continued deforestation and land degradation. However, population pressure combined with improved marketing facilities, ignorance, over exploitation, personal greed, tenure insecurity, faulty government policies regarding settlement of land and breakdown of the traditional systems exerting pressures on these VCF and the overall condition of these important biodiversity rich areas are degrading or shrinking in size and number gradually. Recognizing the traditional and customary resource rights of the indigenous communities in the CHT, acknowledging resource management system, providing tenure security, encouraging communities through legal and financial incentives in protecting these VCF or any other state owned forest areas solely for the conservation of biodiversity following an intensive management plan, resolving long lasting land related conflicts, and at the same time upholding the spirit of CHT Peace Accord 1997 could be important policy tools for the sustainability of these VCF in the CHT. Lessons learned from this study will be useful in formulating effective policies for community based forest management in Bangladesh and other developing countries. 展开更多
关键词 COMMON FORESTS Community-Based Forest MANAGEMENT VILLAGE COMMON FORESTS Chittagong HILL tracts BANGLADESH
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Cronobacter Carriage in Neonate and Adult Intestinal Tracts 被引量:1
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作者 LIU Hui CUI Jing Hua +4 位作者 CUI Zhi Gang HU Guang Chun YANG Yue Lian LI Jian SHI Yu Wen 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第10期861-864,共4页
A total of 7 Cronobocter strains were isolated from 703 fecal samples collected in Jinan from June 13 to December 30, 2011, with the positive rate of Cronobacter spp. being 1.0% (95% confidence interval 0.6%-1.4%). ... A total of 7 Cronobocter strains were isolated from 703 fecal samples collected in Jinan from June 13 to December 30, 2011, with the positive rate of Cronobacter spp. being 1.0% (95% confidence interval 0.6%-1.4%). Three Cronobacter sakazakii stains were isolated from 157 fecal samples of healthy neonates (95% confidence interval 0.4%-5.5%). This number was slightly higher than that isolated from 273 fecal samples of healthy adults, in which 1 strain of C. sakazakii and 1 strain of Cronobacter malonaticus were isolated, and that from 173 fecal samples of adults with acute diarrhea, in which 1 strain of C sakazakii and 1 strain of C. malonaticus were isolated, but the differences were not statistically significant (P〉O.05). The Cronobocter isolates were all from different genetic sources. It should be noted that Cronobacter carriage may cause infection under certain conditions, especially in neonates. 展开更多
关键词 Cronobacter Carriage in Neonate and Adult Intestinal tracts
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Brain gliomas Biological characteristics and correlation with the status of adjacent corticospinal tracts
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作者 Chaoshi Niu Xiaorui Fei +3 位作者 Changxin Wang Jiaming Mei Ying Liu Min Ding 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第17期1347-1352,共6页
Malignant behaviors of brain gliomas include proliferation and infiltration.It remains unclear which behavior influences the status of adjacent corticospinal tracts.Diffusion tensor imaging can show the status of brai... Malignant behaviors of brain gliomas include proliferation and infiltration.It remains unclear which behavior influences the status of adjacent corticospinal tracts.Diffusion tensor imaging can show the status of brain white matter fiber tracts.Ki-67 and CD44/matrix metalloproteinase 9 are sensitive markers for reflecting the proliferation and infiltration of tumor cells.The present study analyzed pre-operative diffusion tensor images of 24 patients with pathologically confirmed World Health Organization glioma(Ⅰ-Ⅳ).We observed lapse,infiltration and destruction of the peri-tumor corticospinal tract following reconstruction,and simultaneously detected the expression of Ki-67,CD44/matrix metalloproteinase 9 in samples.Expression of CD44 and matrix metalloproteinase 9was not significantly correlated to the status of the peri-tumor corticospinal tract(r = 1.597,4.859;P = 0.450,0.088),while Ki-67 expression significantly correlated to its status(r= 6.590,P = 0.037).These findings demonstrate that highly proliferative gliomas result in damage to the peripheral corticospinal tract. 展开更多
关键词 brain gliomas corticospinal tracts diffusion tensor imaging fiber tract PATHOLOGY BIOLOGY
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Permo–Triassic and Liassic Tethyan Oceanic Tracts within the Pontide Belt Along the Southern Margin of Eurasia, Northern Anatolia
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作者 E.SARIFAKIOGLU Y.DILEK +7 位作者 M.SEVIN S.PEHLIVAN O.K EMIR A.MOLLER T.BAYANOVA I.UYSAL M.KELES 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期33-34,共2页
The Pontide belt in northern Turkey includes three major tectonic terranes,the Strandja Massif(Sj M),and the Istanbul(ISZ)and Sakarya Zones(SZ)(Fig.1).We present new age and geochemical data from ophiolites and ... The Pontide belt in northern Turkey includes three major tectonic terranes,the Strandja Massif(Sj M),and the Istanbul(ISZ)and Sakarya Zones(SZ)(Fig.1).We present new age and geochemical data from ophiolites and ophiolitic mélanges within the Sakarya Zone and show that these mafic–ultramafic rocks are the remnants of Tethyan oceanic lithosphere formed in different tectonic settings.The main ophiolite occurrences investigated in this study along the Karakaya Suture(KS)are associated with the latest Triassic Cimmeride orogeny,and in the Küre–Yusufeli ophiolite belt are part of the Alpide orogeny.The Karakaya Suture Zone ophiolites in northern west Turkey are comprised mainly of the Denizgoren(?anakkale)ophiolite,Bo?azk?y(Bursa),Geyve(Sakarya),Almac?k(Düzce)and?ele(Bolu)metaophiolites.The Denizg?ren ophiolite largely contains upper mantle peridotites,which are equivalents of the Permo–Triassic Lesvos peridotites and mélange units farther SW in the northern Aegean Sea.The Bo?azk?y ophiolite includes serpentinite and metagabbro,and the Almac?k and Geyve ophiolites display an almost complete Penrose–type sequence consisting of serpentinizeduppermantleperidotites,cumulate ultramafic–mafic rocks,isotropic gabbros,dolerite and plagiogranite dikes,and extrusive rocks.U–Pb zircon dating of plagiogranite dikes from?ele has revealed an igneous age of 260 Ma,and 255,235,227 Ma from Almac?k(Bozkurt et al.,2012a,b).Consistent with the previouslypublished Permo–Triassic age,we obtained a 268.4±6.3 Ma U–Pb zircon age from a plagiogranite dike within the Almacik ophiolite to the west.This KS ophiolite belt containing the?ele,Almac?k,Geyve ophiolites within the SZ extends westward into the Armutlu Peninsula and then into the Biga Peninsula(i.e.Denizg?ren ophiolite)and most likely connects with the remnants of the Triassic Meliata–Meliac ocean basin(Stampfli and Borel,2002)in the Balkan Peninsula.The KS ophiolites also continue eastward within the Pontide Belt into the Elekda?ophiolite(eastern Kastamonu)and then to the Refahiye ophiolite in NE Anatolia.Triassic granites in the SZ represent a magmatic arc that formed as a result of the northward subduction of the Izmir–Ankara–Erzincan oceanic lithosphere existing during the late Paleozoic through Cretaceous(Sarifakioglu et al.,2014)beneath the Pontides.We obtained a U–Pb zircon age of 231±2 Ma from a metagranitic intrusion into the Variscan basement of the SZ in the Kastamonu region of the central Pontides.This metagranite is enriched in LILE(Rb:63 ppm;Ba:65 ppm;Sr:200 ppm)and depleted in HFSE(Y:12.58 ppm;Yb:1.26 ppm;Ti O2:0.2 wt.%;Nb:7.6 ppm;Hf:3.9 ppm),characterizing it as subduction–related calc-alkaline pluton.Lead(3.9 ppm),U(1.6 ppm)and Ce(59 ppm)contents are interpreted as evidence for contamination by continental crust.The Küre basin to the north opened during the late Triassic to Liassic,following a backarc rifting episode in the central Pontides.Metabasic dike intrusions in the Devrekani metamorphic massif represent the first magmatic stage of this backarc rifting event.Whole-rock 40Ar-39Ar dating ofthe metabasic dikes has yielded cooling ages of 160.5±1.2 Ma. We infer that this age was reset due to thermal heating during the emplacement of the Middle Jurassic granitoids as the Küre oceanic basin was closing. The Küre ophiolite contains upper mantle peridotites and oceanic crustal rocks composed mainly of pillow–massive–breccia basalts, dacitic and rhyolitic lavas–tuffs, diabase dyke swarms, massive gabbros and a limited extent mafic cumulates. We obtained 182.6±1.9 Ma as a whole-rock 40Ar-39 Ar age from a pillow basalt and a U–Pb zircon age of 171±1 Ma from the granitic intrusion cross-cutting the peridotites. The easternmost representatives of the Küre ophiolite occur in the Yusufeli(Artvin) area in the eastern part of the Pontide belt. Here, oceanic crustal rocks are tectonically related to metamorphic rocks of the Variscan basement of the SZ. The ophiolitic crustal rocks contain isotropic gabbro and mafic and felsic dikes. Serpentinized upper mantle peridotites are scarce. Pillow lava basalts are overlain by a thick metasandstone–metashale association with locally foliated meta–lava and some manganiferous chert and mudstone interlayers. We obtained a U–Pb zircon age of 172.5±1.4 Ma from the granitic intrusion cross-cutting the Yusufeli ophiolite and of 181.9±0.9 Ma from a felsic dike(plagiogranite) in the Yusufeli ophiolite. The Middle Jurassic granites are related to the closure of the Küre-Yusufeli marginal ocean basin. The Küre and Yusufeli ophiolites have been previously interpreted as the remnants of the Paleotethys or the Intra-Pontide Ocean. However, we posit that these ophiolites represent amarginal, short-lived(;0 Ma) ocean basin, which opened during the late Triassic through Liassic, and then closed in Dogger. This oceanic lithosphere is similar to the Evros ophiolite in the northeastern Greece in terms of its ages and geochemical characteristics. 展开更多
关键词 Triassic and Liassic Tethyan Oceanic tracts within the Pontide Belt Along the Southern Margin of Eurasia rock KS Pb Permo Northern Anatolia
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Influences of Feeding Lactobacillus on Colonization of the Lactobacillus in Chicks′ Digestible Tracts
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作者 ZhaoYangbing LiuYongjie 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期31-35,共5页
It was carried out with culture solution of Lactobacillus fed to the newborn chicks to observe the influences on colonization of the Lactobacillus in chicks digestible tracts. The results showed that after the chicks... It was carried out with culture solution of Lactobacillus fed to the newborn chicks to observe the influences on colonization of the Lactobacillus in chicks digestible tracts. The results showed that after the chicks were fed Lactobacillus, the amount of the Lactobacillus in chicks digestible tracts significantly increased (P<001) and the Lactobacillus colonized 36h ahead of schedule 展开更多
关键词 lactobacillus chicks digestible tracts COLONIZATION
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A Review on Hydrocarbon Prospectivity in Chittagong Hill Tracts and Adjacent Area
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作者 Md. Rajeun Islam Janifar Hakim Lupin 《Open Journal of Geology》 2020年第2期187-212,共26页
Bangladesh is a country with limited sources of energy and since 1990 natural gas has been its main source of energy. Most of the exploration approaches had been conducted onshore especially in the central and eastern... Bangladesh is a country with limited sources of energy and since 1990 natural gas has been its main source of energy. Most of the exploration approaches had been conducted onshore especially in the central and eastern part of Bangladesh, particularly in northeastern Sylhet basin. Among the hydrocarbon provinces, the East Delta Hill Tract province is an under explored petroleum province in Bangladesh. An exploratory well drilled in Sitakund anticline was found dry but no reasonable cause was perceived why that well went dry. Although many works had been carried out in Chittagong Hill Tracts but none of them was cumulative and descriptive. In this study, the overall hydrocarbon prospect of the Chittagong Hill Tracts was analyzed by mapping of potential zones on the basis of the evaluation of regional structure and construction of lithocolumn of the prospective zones. The five elements of the petroleum system discussed thoroughly to find overall petroleum prospect of the study area. Source rocks of Chittagong Hill Tracts are mainly Bhuban shale, reservoir rock is sandstone from Bhuban-Bokabil formation, the way of migration path is both through longitudinal and cross fault. The data of source rock and seal is collected from previous researches. Multiple types of traps have been found there. Conventional anticlinal traps which are highly disturbed due to tectonic instability & the core part are shale diapirism. Most of the anticlines are plunging and the nose or plunge area might be prospective to HC for being comparatively less faulted. Broad synclinal areas between tight narrow anticlines are another prospective area for HC. These similar types of synclines are also found in Tripura, India which is a highly prospective area for petroleum and their small anticlinal hums within syncline are also prospective. Some stratigraphic traps have also been found in Tripura from where production has been started already. Both Chittagong Hill Tracts and Tripura Fold Belts are parts of great Arakan Fold Belts, so similar type of structures might be prospective here. Apart from these, Bangladesh is a deltaic country. So stratigraphic trapment like channel sand, pinch-outs is possible. Considering all the elements of petroleum prospectivity of the area and factors discussed above, it is quite clear that Chittagong hill tracts might be the next target for HC exploration program. 展开更多
关键词 PETROLEUM Prospect Lithocolumn STRATIGRAPHIC SUCCESSION PETROLEUM System UNCONVENTIONAL Reservoir Channel Sand DIAPIRISM Chittagong HILL tracts
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Anatomical peculiarities of sensory tracts of the wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect
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作者 Sixin Ouyang Zhenshan Peng Jianguo Tan Tianhong Peng Jianzhong Xiao 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期47-49,共3页
BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve s... BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator. OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility. DESIGN:Duplicated and measured design.SETTING : Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris Iongus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve. MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect. RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non-damaged separated length was about 10.0 cm to 14.0 cm. The third, second and first tracts of cutaneous branches at digital interspace and radialis of thumb arrayed from ulnaris to radialis by turns, and numbers of bands were 6.9, 7.4 and 7.2, respectively. The bands in total were 21.6. Cutaneous branches of palm entered from lateral margin of radialis and were completely separated at wrist. Two-thirds of ulnaris at nerve stem, i.e. the third, second and first tracts of cutaneous branches at digital interspace, were separated, which had little effect on sensation in distribution of median nerve. ② Its nutrient vessels originated from radial arteries about 6.2 (6.1-6.6) cm above radial styloid process were 1.2 (1.1-1.4) mm in outer diameter. The length was 5.7 (5.1-6.1) cm.③ The length of wrist ulnar nerve were 9.4 (8.9-9.7) cm and the number of nervous tract were 14 to 19, in which sensory tracts on the anterior external side were approximately equal to motor and mixed tracts on the posterior internal side in quantity. Sensory tracts were located at radialis of palm and motor tracts were located at ulnaris of back. CONCLUSION :① Character and position of median nerve fibre bundle are clear, and length of non-damage separation of sensory tracts is coincidence with the request of transferring to bridge. ② Summation of the third, second and first tracts of cutaneous branches at digital interspace may be satisfactory to bridge of ulnar nerve at wrist (14-19 bands). ③ This technique has little effect on sensation in distribution of median nerve. Nutrient artery of median nerve locates constantly; journey table is superficial and is easily to find out; caliber of arterial canal is thick; blood supply is plentiful; length of pedicel is suitable for translocation. The sensery tracts of wrist median nerve pedicled with nutrient vessels can be applied as nervous grafts to join injured gap in wrist ulnar nerve. 展开更多
关键词 length Anatomical peculiarities of sensory tracts of the wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect
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A Study of Compound Action Potentials in Current-Coupled Tracts: the General Case
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作者 Aman Chawla Salvatore Domenic Morgera 《Journal of Applied Mathematics and Physics》 2023年第11期3345-3353,共9页
In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the ... In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the paper is that, for the case of biophysically inhomogeneous axon tracts, the compound action potential is governed by a Hodgkin-Huxley like equation itself in certain cases. The paper extends an earlier result for the identical axon case. 展开更多
关键词 Compound Action Potentials Current-Mediated Coupling Biophysically Inhomogeneous Axon tracts Hodgkin-Huxley Equation Identical Axon Case
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FoxO4 is the main forkhead transcriptional factor localized in the gastrointestinal tracts of pigs 被引量:9
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作者 ZHOU Zhen-qi WANG Tian PAN Ling-mei HUANG Rui-hua SHI Fang-xiong 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第1期39-44,共6页
Forkhead box (Fox) proteins play critical roles in the regulation of differentiation, proliferation, immunity and aging of cells. Most studies on Fox proteins are limited to cultured cells and rodent. The aim of the... Forkhead box (Fox) proteins play critical roles in the regulation of differentiation, proliferation, immunity and aging of cells. Most studies on Fox proteins are limited to cultured cells and rodent. The aim of the current study is to detect by immunohistrochemistry whether FoxO1, FoxO3a and FoxO4 proteins are localized in the stomach and intestine of the pig. The results showed that FoxO4 exists in the mucosa in all parts of the stomach and intestine; FoxO3a exists mainly in the lamina propria and muscularis of some parts. However, FoxOl is not detectable in all parts of the stomach and intestine. Collectively, the results of the present study indicate that there exists a distinct expression pattern of Fox proteins, and that FoxO4 is a primary forkhead transcriptional factor localized in the gastrointestinal tracts of the pig. 展开更多
关键词 FORKHEAD FOXO Gastrointestinal tract IMMUNOHISTOCHEMISTRY SWINE
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Water quality of Kaptai reservoir in Chittagong Hill Tracts of Bangladesh 被引量:2
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作者 Shyamal Karmakar S. M. Sirajul Haque +1 位作者 M. Mozaffar Hossain M. Shafiq 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期87-92,共6页
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 samplings ... 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 samplings 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 sampling 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. 展开更多
关键词 Karnaphuli river lake water quality Chittagong Hill Tract
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Microglia activation mediated by toll-like receptor-4 impairs brain white matter tracts in rats 被引量:5
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作者 Xinglong Yang Jingdong Zhang +3 位作者 Lian Duan Huangui Xiong Yanping Jiang Houcheng Liang 《The Journal of Biomedical Research》 CAS CSCD 2018年第2期136-144,共9页
Microglia activation and white matter injury coexist after repeated episodes of mild brain trauma and ischemic stroke. Axon degeneration and demyelination can activate microglia; however, it is unclear whether early m... Microglia activation and white matter injury coexist after repeated episodes of mild brain trauma and ischemic stroke. Axon degeneration and demyelination can activate microglia; however, it is unclear whether early microglia activation can impair the function of white matter tracts and lead to injury. Rat corpus callosum(CC) slices were treated with lipopolysaccharide(LPS) or LPS + Rhodobacter sphaeroides(RS)-LPS that is a toll-like receptor 4(TLR-4) antagonist. Functional changes reflected by the change of axon compound action potentials(CAPs) and the accumulation of β-amyloid precursor protein(β-APP) in CC nerve fibers. Microglia activation was monitored by ionized calcium binding adaptor-1 immunofluorescent stain, based on well-established morphological criteria and paralleled proportional area measurement. Input-output(I/O) curves of CAPs in response to increased stimuli were significantly downshifted in a dose-dependent manner in LPS(0.2, 0.5 and 1.0μg/mL)-treated slices, implying that axons neurophysiological function was undermined. LPS caused significant β-APP accumulation in CC tissues,reflecting the deterioration of fast axon transport. LPS-induced I/O curve downshift and P-APP accumulation were significantly reversed by the pre-treatment or co-incubation with RS-LPS. RS-LPS alone did not change the I/O curve.The degree of malfunction was correlated with microglia activation, as was shown by the measurements of proportional areas. Function of CC nerve fibers was evidently impaired by microglia activation and reversed by a TLP-4 antagonist, suggesting that the TLP-4 pathway lead to microglia activation. 展开更多
关键词 lipopolysaccharide Rhodobacter sphaeroides toll-like receptor 4 microglia activation white matter tract malfunction
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Effects of cartilaginous rings on airflow and particle transport through simplified and realistic models of human upper respiratory tracts 被引量:1
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作者 Vivek Kumar Srivastav Akshoy Ranjan Paul Anuj Jain 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第6期883-892,共10页
In the present study, computational fluid dynamics (CFD) is used to investigate inspiratory and expiratory airflow characteristics in the human upper respiratory tract for the purpose of identifying the probable loc... In the present study, computational fluid dynamics (CFD) is used to investigate inspiratory and expiratory airflow characteristics in the human upper respiratory tract for the purpose of identifying the probable locations of particle deposition and the wall injury. Computed tomography (CT) scan data was used to reconstruct a three dimensional respiratory tract from trachea to first generation bronchi. To compare, a simplified model of respiratory tract based on Weibel was also used in the study. The steady state results are obtained for an airflow rate of 45 L/min, corresponding to the heavy breathing condition. The velocity distribution, wall shear stress, static pressure and particle deposition are compared for inspiratory flows in simplified and realistic models and expiratory flows in realistic model only. The results show that the location of cartilaginous rings is susceptible to wall injury and local particle deposition. 展开更多
关键词 Upper respiratory tract Cartilaginous rings Computational fluid dynamics (CFD) Computed tomogra- phy (CT) Wall shear stress Particle deposition.
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Biotinylated dextran amine tracing of nerve tracts determines regeneration of corticospinal tracts after neural stem cell transplantation
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作者 Jun Wu Fenghua Chen Mingyu Zhang Tao Song Jinfang Liu Jiasheng Fang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第28期2183-2187,共5页
We investigated regeneration of the corticospinal tract and rearrangement of corticospinal nerves after spinal cord injury by biotinylated dextran amine (BDA) nerve tract tracing after neural stem cell transplantati... We investigated regeneration of the corticospinal tract and rearrangement of corticospinal nerves after spinal cord injury by biotinylated dextran amine (BDA) nerve tract tracing after neural stem cell transplantation. Neural stem cell transplantation increased motor function scores of rats at 3 weeks after spinal cord transection injury at the thoracic 10 segment. A proportion of BDA-labeled corticospinal tract regenerated through the spinal cord injury site at 12 weeks after transplantation. Electron microscopy revealed that the regenerated BDA-labeled nerve terminals formed new synaptic connections with neurons at the distal end of the injured site. These findings indicate that BDA nerve tract tracing effectively provides anatomic and morphological evidence of recovery after spinal cord injury. 展开更多
关键词 nerve tract tracing neural stem cells TRANSPLANTATION spinal cord injury corticospinal tract biotinylated dextran amine neural regeneration
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Compression of the bilateral corticospinal tracts by bilateral pontine hemorrhage A diffusion tensor tractography study
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作者 Hyeok Gyu Kwon Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第4期317-320,共4页
Bilateral spontaneous pontine hemorrhage is rare. In addition, bilateral corticospinal tract (CST) involvement in the pons may accompany serious motor sequelae. A 45-year-old right-handed woman was admitted for bila... Bilateral spontaneous pontine hemorrhage is rare. In addition, bilateral corticospinal tract (CST) involvement in the pons may accompany serious motor sequelae. A 45-year-old right-handed woman was admitted for bilateral pontine hemorrhage. The patient presented with moderate quadriparesis at stroke onset and quickly recovered to the point of being able to extend the muscles of all four extremities against resistance, at 2 weeks from onset. At 4 weeks after stroke onset, she was able to perform all fine motor activities, as well as to walk with a normal gait. Diffusion tensor tractography results showed that the CSTs of both hemispheres originated from the primary sensorimotor cortex and descended through the corona radiata, the posterior limb of the internal capsule, midbrain, anterior pons, and the anterior medulla, along the known pathway of the CST. However, at midbrain and pons, the CSTs were compressed posterolaterally. The contralateral primary sensorimotor cortex, centered on the precentral knob, was activated during movement of either hand of the patient, as shown by functional MRI, which indicates the preservation of lateral CST. Findings from this study suggest that diffusion tensor tractography may be helpful in the elucidation of the CST status in patients with pontine hemorrhage. 展开更多
关键词 diffusion tensor imaging diffusion tensor tractography functional MRI corticospinal tract STROKE motor recovery pontine hemorrhage
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