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Mineralogy and whole-rock geochemistry of the Oligocene Barail Group of rocks of Belt of Schuppen,Northeast India:Implications for tectono-provenance and paleo-weathering
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作者 Manash Pratim Gogoi Yunpeng Dong +6 位作者 Pradip Borgohain Devojit Bezbaruah Arvind Pandey Yadav Krishna Gogoi Garima Konwar Gautam Raj Bawri Bubul Bharali 《Acta Geochimica》 EI CAS CSCD 2024年第5期904-932,共29页
The petrographic and geochemical attributes of the Oligocene Barail Group of rocks are used to decipher the likely source area(s)or tectonic domains,as this sequence of rocks was deposited in a foreland basin governed... The petrographic and geochemical attributes of the Oligocene Barail Group of rocks are used to decipher the likely source area(s)or tectonic domains,as this sequence of rocks was deposited in a foreland basin governed by orogenic domain,namely the North-east Arunachal Himalayas.The river system that gave rise to the Brahmaputra River(Yarlung-Tsangpo),which flowed through several tectonic domains of the Himalayan ranges,primarily from BomiChayu,Gangadese Granitoid,Higher Himalayan Leucogranites,and Namche Barwa into the proto Bengal Basin now a part of Assam Arakan Basin and Naga Schuppen Belt,was the main source of the sandstone formation of the Barail Group.The purpose of sandstone petrography,which combines modal analysis with XRF(Major Oxides)and HR-ICPMS(Trace&Rare Earth Elements)research,is to identify the type of source rock(s),their weathering pattern,and its paleo-environmental circumstances.These sandstones were formed from recycled orogen and include lithic and sublithic arenite variants with advanced texture and chemical maturity.The sediments were felsic(Th/Co:1.38,Cr/Th:9.78,La/Lu:11.58,Th/Sc:0.99,Eu/Eu*:0.66,La/Sc:3.05,La/Co:4.18),with contributions from intermediate source rocks and low-rank metamorphics deposited in an active continental margin to a continental island arc setting.Climatic conditions impacted the sediments of Barails,characterised by being warm and semi-humid to humid which resulted in moderate to a high degree of chemical weathering,as shown by weathering indices like CIA(79.14),PIA(85.47),CIW(86.9),WIP(32.50),ICV(0.71),and Th/U(6.03),which were further additionally supported by C-Value(1.01),PF(1.20),Sr/Cu(2.04),and Rb/Sr(0.97). 展开更多
关键词 Belt of Schuppen Barail Group Sandstone PETROGRAPHY Geochemistry PROVENANCE Tectonic setting
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Tuning of Optical Properties via Annealing of Bismuth Ferrite (BiFeO3) Thin Films
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作者 Harish Kumar Meena Khushbu Meena +4 位作者 Reena Verma Karishma Jain Sushil Kumar Jain Kedar Babu Sharma Balram Tripathi 《Open Journal of Composite Materials》 2024年第3期124-131,共8页
In this study we are reporting annealing induced optical properties of bismuth ferrite (BiFeO3) thin films deposited on glass substrate via spin coating at 5000 rpm. The structural, optical and surface morphology of B... In this study we are reporting annealing induced optical properties of bismuth ferrite (BiFeO3) thin films deposited on glass substrate via spin coating at 5000 rpm. The structural, optical and surface morphology of BiFeO3 (BFO) thin films have been studied via X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Optical absorption (UV-Vis) and Photoluminescence (PL) spectroscopy. XRD spectra confirm annealing induced phase formation of BiFeO3 possessing a rhombohedral R3c structure. The films are dense and without cracks, although the presence of porosity in BFO/glass was observed. Moreover, optical absorption spectra indicate annealing induced effect on the energy band structure in comparison to pristine BiFeO3. It is observed that annealing effect shows an intense shift in the UV-Vis spectra as diffuse absorption together with the variation in the optical band gap. The evaluated optical band gap values are approximately equal to the bulk band gap value of BiFeO3. 展开更多
关键词 Optical Properties ANNEALING FERROELECTRICS Photo Luminescence BFO Thin Films
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Study of Structural, Optical, Electrical and Dielectric Properties of Gd-Doped ZnO Composites Synthesized by Solid State Reaction Method
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作者 Santosh Kumar Kundara Kanhaiya Chawla +3 位作者 Dinesh Kumar Yadav Chhagan Lal Balram Tripathi Narendra Jakhar 《Open Journal of Composite Materials》 2024年第2期91-108,共18页
In this manuscript, we are reporting structural, bonding, optical, dielectric, and electrical properties of Gd-doped ZnO composite samples (Zn<sub>1</sub><sub>−</sub><sub>x</sub>Gd&... In this manuscript, we are reporting structural, bonding, optical, dielectric, and electrical properties of Gd-doped ZnO composite samples (Zn<sub>1</sub><sub>−</sub><sub>x</sub>Gd<sub>x</sub>O, x = 0, 0.05, 0.10) prepared by solid-state reaction method. XRD spectra confirm the wurtzite hexagonal phase with a grain size distribution of 42 - 47 nm. The FT-IR spectra confirm bonding behavior like Zn-O, O=C=O, and O-H stretching modes. FESEM micrographs show that the grains of crystallites possess nearly spherical morphology. Optical absorption spectra confirm that the optical band gap decreases systematically from 3.19 eV to 3.15 eV for x = 0.0 to x = 0.10 samples. For all samples, PL spectra exhibited near-band emission, blue emission, and green emission peaks. The dielectric constant decreases as the applied frequency increases. Hall effect results show that with increasing doping concentration of Gd, mobility and resistivity increase while bulk concentration decreases. Current-Voltage study shows that current increases when temperature is increased. Rare earth-doped ZnO is potential material used for optoelectronics and spintronics device applications. Properties of Gd-doped ZnO are studied by various research groups, but dielectric studies are limitedly reported. Therefore, the present research work aims to study the change of electrical, optical, and dielectric properties of Gd-doped ZnO for device applications. 展开更多
关键词 ZnO:Gd Composites Optical Band Gap Green Emission Dielectric Constant
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Vas deferens, a site of male contraception: an overview 被引量:6
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作者 NirmalK.Lohiya B.Manivannan +1 位作者 PradyumnaK.Mishra NeelamPathak 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第2期87-95,共9页
The vas deferens is a site which can be exploited for male contraception without undue side effects. The only ef-fective technique available for male contraception is vasectomy, being practiced world wide, despite tha... The vas deferens is a site which can be exploited for male contraception without undue side effects. The only ef-fective technique available for male contraception is vasectomy, being practiced world wide, despite that it is a perma-nent surgical procedure and its successful reversal is not assured. Although no-scalpel vasectomy minimizes surgicalprocedures, the fate of its reversal is akin to that of vasectomy. Several occlusive and non-occlusive vasal procedureswhich claim to be reversible without surgical intervention, possess more disadvantages than advantages. Vas occlusionwith plug, ' Shug' or medical grade silicone rubber, although claimed to produce reversible azoospermia without affect-ing spermatogenesis, requires skilled microsurgery for their implantation and later removal. RISUG^R, a non-scleroticpolymer styrene maleic anhydride (SMA), could be more advantageous than vasectomy and other vas occlusive proce-dures in that it could be a totally non-invasive procedure by 'no-scalpel injection' and 'non-invasive reversal'. It isclaimed to offer long-term contraception without adverse side effects and also to be possible as a male spacing methodby repeated vas occlusion and non-invasive reversal. The drug is currently under multicentre Phase Ⅲ clinical trial. 展开更多
关键词 male contraception vas deferens VASECTOMY vas occlusives injectable plugs RISUG^R
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Human sperm immobilization effect of Carica papaya seed extracts: an in vitro study 被引量:6
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作者 Nirmal K Lohiya Lalit K Kothari +2 位作者 B Manivannan Pradyumna K Mishra Neelam Pathak 《Asian Journal of Andrology》 SCIE CAS CSCD 2000年第2期103-109,共7页
Aim: To examine if the seed extracts of Carica papaya, which showed anfispermatogenic/sperm immobilizationproperties in animal models, could cause human sperm immobilization in vitro. Methods: Chloroform extract, ben-... Aim: To examine if the seed extracts of Carica papaya, which showed anfispermatogenic/sperm immobilizationproperties in animal models, could cause human sperm immobilization in vitro. Methods: Chloroform extract, ben-zene chromatographic fraction of the chloroform extract, its methanol and ethyl acetate sub-fractions and the isolatedcompounds from the sub-fractions i. e., ECP 1 & 2 and MCP 1 & 2, of the seeds of Carica papaya were used at con-centrations of 0.1%, 0.5%, 1% and 2%. Sperm motility was assessed immediately after addition of extracts and ev-ery 5 minutes thereafter for 30 minutes. Results: There were dose-dependent spermicidal effects showing an instantfall in the sperm motility to less than 20% at 2% concentration. Isolated compounds ECP 1 & 2 were more effective in-ducing a motility of less than 10%. Many of the spermatozoa became vibratory on the spot. Total inhibition of motilitywas observed within 20-25 rain at all concentrations of all products. Scanning and transmission electron microscopyrevealed deleterious changes in the plasma membrane of the head and mid-piece of spermatozoa. Sperm viability testand the number of abnormal spermatozoa after completion of incubation suggested that the spermatozoa were infertile.The effects were spermicidal but not spermiostatic as revealed by the sperm revival test. Conclusion: The results re-veal spermicidal activity in vitro of the seed extracts of Carica papaya. 展开更多
关键词 human sperm sperm immobilization spermicidal agents Carica papaya
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Role of NiMn_(9.3)Al_(4.0)Co_(14.1)Fe_(3.6)alloy on dehydrogenation kinetics of MgH_(2) 被引量:6
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作者 Priyanka Meena Ramvir Singh +1 位作者 V.K.Sharma I.P.Jain 《Journal of Magnesium and Alloys》 SCIE EI CAS 2018年第3期318-325,共8页
Hydriding and dehydriding properties of MgH_(2)-x wt.%NiMn_(9.3)Al_(4.0)Co_(14.1)Fe_(3.6)(x=10,25,50)nanocomposites have been investigated in present work.Doped alloy was prepared by arc melting method and ball milled... Hydriding and dehydriding properties of MgH_(2)-x wt.%NiMn_(9.3)Al_(4.0)Co_(14.1)Fe_(3.6)(x=10,25,50)nanocomposites have been investigated in present work.Doped alloy was prepared by arc melting method and ball milled with MgH_(2)to get nanocomposites.Onset temperature as low as 180℃was observed for MgH_(2)-50 wt%system which is 80℃lower than the as-milled MgH_(2)giving 131.34 KJ/mol activation energy.Structural analysis shows tetragonal,orthorhombic and monoclinic phases for MgH_(2),Al_(60)Mn_(11)Ni_(4)and Mg_(2)NiH_(4).Morphology by SEM were undertaken to investigate the effect of hydrogenation on nanostructured alloy.DSC studies show a single broad exothermic peak in the temperature range 48℃-353℃after alloy addition in MgH_(2).These results indicate that the hydrogenation properties of MgH_(2)nanocomposite have been improved compared to the as-milled MgH_(2). 展开更多
关键词 Hydrogen storage Activation energy Mg based nanocomposites Phase structure TGA
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Effect of adrenalectomy and hydrocortisone on ventral prostate of rats 被引量:3
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作者 Neena Nair R.S.Bedwal R.S.Mathur 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第4期289-300,共12页
Aim: To study the effects of adrenalectomy and hydrocortisone on the ventral prostate of SD rats. Methods: Inadrenalectomised (ADX) and ADX + hydrocortisone (1, 2, or 4 mg) treated rats, the prostatic histology and th... Aim: To study the effects of adrenalectomy and hydrocortisone on the ventral prostate of SD rats. Methods: Inadrenalectomised (ADX) and ADX + hydrocortisone (1, 2, or 4 mg) treated rats, the prostatic histology and thecholesterol, protein, zinc, and copper levels and the enzymic profile (acid phosphatase, alkaline phosphatase, aryl sul-phatase, lactic dehydrogenase, and leucine aminopeptidase) in the prostatic tissue were determined; the serum hormon-al profile (testosterone, FSH and LH) was also assayed. Results; Adrenalectomy caused a progressive degenerationin prostatic structure that was not reversed by hydrocortisone treatment. The serum testosterone were significantly lowerin ADX than in sham operated rats and lower in ADX + hydrocortisone than in ADX-C rats (P < 0.01). The serumFSH and LH were below the detection limit of 1 mIU/mL. The enzymatic activity was higher in ADX than in sham op-erated rats and higher in ADX + hydrocortisone than in ADX-C rats (P<0.05-0.01). The prostatic zinc levels weresignificantly higher in sham operated than in ADX, and higher in ADX-C than in ADX + hydrocortisone rats (P < 0.05-0.01). The prostatic copper level was significantly lower in sham operated than in ADX, and lower in ADX-C thanin the ADX + hydrocortisone rats (P <0.01). Conclusion; In rats, adrenalectomy leads to pathological and func-tional changes of the prostate. Hydrocortisone treatment at the doses employed did not reverse these changes. (Asian JAndrol 2001 Dec; 3: 289 - 300) 展开更多
关键词 ADRENALECTOMY ventral prostate hydrocortisone TESTOSTERONE FSH LH CHOLESTEROL zinc copper acid phosphatase alkaline phosphatase aryl sulphatase lactic dehydrogenase leucine aminopeptidase
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Sperm characteristics and ultrastructure of testes of rats after long-term treatment with the methanol subfraction of Carica papaya seeds 被引量:4
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作者 Boomi Manivannan Ruchi Mittal +2 位作者 Shipra Goyal Abdul S. Ansari Nirmal K. Lohiya 《Asian Journal of Andrology》 SCIE CAS CSCD 2009年第5期583-599,I0003,共18页
The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol s... The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol subfraction (MSF) of C. papaya seeds. The test substance was administered orally to the male albino rats (n = 40) at 50 mg per kg body weight each day for 360 days. Control animals (n = 40) received olive oil as a vehicle. Recovery was assessed up to 120 days after treatment withdrawal. Sperm parameters, serum testosterone levels, fertility, histology and ultrastructure of the testis, haematology and serum clinical chemistry were evaluated to establish the safety and efficacy of the test substance. Safety of long-term treatment was evidenced by unaltered health status, organ weight, haematology and clinical chemistry, and by an increase in body weight. The mechanism of contraception was shown by reduction in nuclear and cytoplasmic volume, normal nuclear characteristics and vacuolization in the cytoplasmic organelles of the Sertoli cells, as well as nuclear degeneration in spermatocytes and spermatids indicating disturbed spermatogenesis. Leydig cells were normal. Initial effects were observed in Sertoli cells at 60 days of treatment. Spermatocytes and spermatids were affected after 120-240 days of treatment. A significant decline in sperm count and viability, total inhibition of sperm motility, increased numbers of sperm abnormalities, normal serum testosterone levels and 100% sterility were evident after 60 days of treatment. All the altered parameters, including percent fertility, were restored to control level 120 days after treatment withdrawal. It is concluded that the MSF is safe for long-term treatment and the mechanism of contraception is shown by its effect on spermatid differentiation in the testis, possibly mediated by the Sertoli cell factors. 展开更多
关键词 Carica papaya seeds male contraception SPERMATOZOA TESTIS ULTRASTRUCTURE
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Molecular Basis of Aluminium Toxicity in Plants: A Review 被引量:9
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作者 Nidhi Gupta Shailendra Singh Gaurav Ashwani Kumar 《American Journal of Plant Sciences》 2013年第12期21-37,共17页
Aluminium toxicity in acid soils having pH below 5.5, affects the production of staple food crops, vegetables and cash crops worldwide. About 50% of the world’s potentially arable lands are acidic. It is trivalent ca... Aluminium toxicity in acid soils having pH below 5.5, affects the production of staple food crops, vegetables and cash crops worldwide. About 50% of the world’s potentially arable lands are acidic. It is trivalent cationic form i.e. Al3+ that limits the plant’s growth. Absorbed Aluminium inhibits root elongation and adversely affects plant growth. Recently researches have been conducted to understand the mechanism of Aluminium toxicity and resistance which is important for stable food production in future. Aluminium resistance depends on the ability of the plant to tolerate Aluminium in symplast or to exclude it to soil. Physiological and molecular basis of Aluminium toxicity and resistance mechanism are important to understand for developing genetically engineered plants for Al toxicity resistance. This paper provides an overview of the state of art in this field. 展开更多
关键词 Aluminium TOXICITY Acid SOILS MALATE CITRATE WHEAT Field CROPS
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Sperm motility inhibitory effect of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkey, Presbytis entellus entellus 被引量:3
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作者 Nirmal K. Lohiya Boomi Manivannan Shipra Goyal Abdul S. Ansari 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第2期298-306,共9页
Aim: To assess the contraceptive efficacy of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkeys. Methods: The test substance was given p.o. to five monkeys... Aim: To assess the contraceptive efficacy of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkeys. Methods: The test substance was given p.o. to five monkeys at 50 mg/kg body weight/day for 360 days. Control animals (n = 3) received olive oil as vehicle. Sperm parameters as per World Health Organization standards, sperm functional tests, morphology of testis and epididymis, haematology, clinical biochemistry, serum testosterone and libido were evaluated. Following completion of 360 days treatment the animals were withdrawn from the treatment and the recovery pattern was assessed by semen analysis and sperm functional tests. Results: Total inhibition of sperm motility was observed following 60 days of treatment that continued until 360 days study period. Sperm count, percent viability and percent normal spermatozoa showed a drastic decline following 30 days of treatment. Sperm morphology showed predominant mid piece abnormalities. Sperm functional tests scored in sterile range. Histology and ultrastructure of testis revealed vacuolization in the Sertoli cells and germ cells. Loss of cytoplasmic organelles was evident in spermatocytes and round spermatids. Histology and ultrastructure of epididymis of treated animals were comparable to those of control animals. Hematological and serum clinical parameters and testosterone levels fluctuated within the control range throughout the study period. Recovery was evident following 60--120 days of treatment withdrawal. Conclusion- The results suggest that the benzene chro- matographic fraction of the chloroform extract of the seeds of Carica papaya shows contraceptive efficacy without adverse toxicity, mediated through inhibition of sperm motility. (Asian JAndro12008 Mar; 10: 298-306) 展开更多
关键词 male contraception Carica papaya seeds sperm motility inhibition TESTIS EPIDIDYMIS langur monkeys
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Effect of Alstonia scholaris bark extract on testicular function of Wistar rats 被引量:3
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作者 R. S. Gupta Rakhi Sharma +4 位作者 Aruna Sharma A.K. Bhatnager M.P. Dobhal Y.C. Joshi M.C. Sharma 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第3期175-178,共4页
Abstract Aim: To evaluate the antifertility effect ofAlstonia scholaris bark extract in male rats. Methods: In male Wistar rats Alstonia scholaris bark extract was given by oral route at a dose of 200 mg/day for 60 da... Abstract Aim: To evaluate the antifertility effect ofAlstonia scholaris bark extract in male rats. Methods: In male Wistar rats Alstonia scholaris bark extract was given by oral route at a dose of 200 mg/day for 60 days. The fertility and testicular function were assessed by mating tests, sperm motility, sperm concentration, biochemical indices and testicular cell population dynamics. Results: Oral feeding with the extract at a dose of 200 mg/day for the period of 60 days did not cause body weight loss, while the weights of testes, epididymides, seminal vesicle and ventral prostate were significantly reduced. The production of step-19 spermatids was reduced by 79.6% in treated rats. The population of preleptotene and pachytene spermatocytes were decreased by 61.9% and 60.1%, respectively. Spermatogonia and Sertoli cell population were also affected. The seminiferous tubule and Leydig cell nuclear area were reduced significantly (P<0.01) when compared to the controls. Reduced sperm count and motility resulted in a total suppression of fertility. A significant fall in the protein and sialic acid content of the testes, epididymides, seminal vesicle and ventral prostate as well as glycogen content of testes were also noticed. The fructose content in the seminal vesicle was lowered whereas the testicular cholesterol was elevated as compared with the controls. The following compounds were obtained from the extract with chromatographic separation over Si-gel column: α-amyrin, β-amyrin, lupiol acetate, venenative, rhazine and yohimbine. Conclusion: At the dose level employed, Alstonia scholaris bark extract has a significant antifertility effect in male rats; the primary site of action may be post meiotic germ cells (Step 19 spermatids). 展开更多
关键词 Alstonia scholaris TESTIS sperm motility sialic acid Sertoli cells
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Effect of Semecarpus anacardium fruits on reproductive function of male albino rats 被引量:3
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作者 Arti Sharma Pramod Kumar Verma V.P.Dixit 《Asian Journal of Andrology》 SCIE CAS CSCD 2003年第2期121-124,共4页
<abstract>Aim: To evaluate the effect of an ethanolic extract of Semecarpus anacardium fruits on spermatogenesis in albino rats. Methods: Male albino rats were fed with a 50 % ethanolic extract of Semecarpus ana... <abstract>Aim: To evaluate the effect of an ethanolic extract of Semecarpus anacardium fruits on spermatogenesis in albino rats. Methods: Male albino rats were fed with a 50 % ethanolic extract of Semecarpus anacardium fruit at 100 mg·kg-1.day-1, 200 mg·kg-1·day-1 and 300 mg·kg-1·day-1 for 60 days. Fertility test was performed after 60 days of treatment. Sperm motility and density were observed in the cauda epididymis. Biochemical and histological analyses of the blood and reproductive organs were done. Recovery of fertility was followed to evaluate the reversibility of drug action. Results: S. anacardium fruit extract administration resulted in spermatogenic arrest in albino rats. The sperm motility and density was reduced significantly. The RBC and WBC counts, haemoglobin, haematocrit, blood sugar and urea were found to be within the normal range in the whole blood. The protein, cholesterol and glycogen in the testes and the fructose in the seminal vesicle were significantly decreased after the treatment. The fruit extract feeding caused marked reduction in the number of primary spermatocytes, secondary spermatocytes and spermatids. The number of mature Leydig cells was also decreased and degenerating cells increased proportionately. Conclusion: 5. anacardium fruit extract causes spermatogenic arrest in albino rats. 展开更多
关键词 Semecarpus anacardium SPERMATOGENESIS ANDROGEN SPERMATOCYTES Leydig cells
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Age of the Marwar Supergroup,NW India:A note on the U–Pb geochronology of Jodhpur Group felsic volcanics 被引量:5
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作者 Huiru Xu Joseph G.Meert Manoj K.Pandit 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第1期244-254,共11页
The Marwar Supergroup(NW Peninsular India)is thought to be of Ediacaran-Cambrian age,based on previous paleontological and geochronological studies.However,direct constraints on the onset of sedimentation within the M... The Marwar Supergroup(NW Peninsular India)is thought to be of Ediacaran-Cambrian age,based on previous paleontological and geochronological studies.However,direct constraints on the onset of sedimentation within the Marwar basin are still scarce.In this study,we report U–Pb zircon,LA-ICP-MS,and SIMS ages from the Chhoti Khatu felsic volcanic rocks,interlayered with the Jodhpur Group sandstones(Lower Marwar Supergroup).The cathodoluminescence images of the zircons indicate complex morphologies,and core-rim textures coupled with the wide range of ages indicate that they are likely inherited or in the case of thin poorly indurated ash-beds,detrital in origin.The age spectra of 68 zircon analyses from our sampling display a dominant 800–900 Ma age peak corresponding to the age of basement"Erinpura granite"rocks in the region.The youngest inherited zircon from a felsic ash layer yielded a U–Pb age of651 Ma±18 Ma that,together with previous studies and paleontological evidence,indicates a postCryogenian age for the initiation of Marwar sedimentation following a~125 Ma hiatus between the end of Malani magmatism and Marwar deposition. 展开更多
关键词 Marwar Supergroup Sedimentation age Zircon U-Pb dating Chhoti Khatu felsic volcanics
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Effects of chemical reactions on MHD micropolar fluid flow past a vertical plate in slip-flow regime 被引量:2
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作者 R.C.Chaudhary Abhay Kumar Jha 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第9期1179-1194,共16页
Heat and mass transfer effects on the unsteady flow of a micropolar fluid through a porous medium bounded by a semi-infinite vertical plate in a slip-flow regime are studied taking into account a homogeneous chemical ... Heat and mass transfer effects on the unsteady flow of a micropolar fluid through a porous medium bounded by a semi-infinite vertical plate in a slip-flow regime are studied taking into account a homogeneous chemical reaction of the first order. A uniform magnetic field acts perpendicular to the porous surface absorb micropolar fluid with a suction velocity varying with time. The free stream velocity follows an exponentially increasing or decreasing small perturbation law. Using the approximate method, the expressions for the velocity microrotation, temperature, and concentration are obtained. Futher, the results of the skin friction coefficient, the couple stress coefficient, and the rate of heat and mass transfer at the wall are presented with various values of fluid properties and flow conditions. 展开更多
关键词 micropolar fluid MICROROTATION chemical reaction SLIP-FLOW magnetohy-drodynamics heat and mass transfer
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Effect of adrenalectomy on rat epididymidis 被引量:1
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作者 Neena Nair R.S. Bedwal R.S. Mathur 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第4期273-279,共7页
AIM: To investigate the effect of adrenalectomy (ADX) on the epididymidis of Sprague-Dawley rats. METHODS: The histological, biochemical (cholesterol protein, zinc, copper, alkaline and acid phosphatase aryl sulphatas... AIM: To investigate the effect of adrenalectomy (ADX) on the epididymidis of Sprague-Dawley rats. METHODS: The histological, biochemical (cholesterol protein, zinc, copper, alkaline and acid phosphatase aryl sulphatase, lactic dehydrogenase and leucine amino peptidase) and hormonal (FSH, LH and testosterone) changes of caput and cauda epididymis in ADX rats were observed. RESULTS: Organ wet weight, histological studies and morphometric measurements indicated a cellular degeneration in caput and cauda epididymis of ADX rats. Serum testosterone level was significantly lower in ADX than in sham-operated rats, while the serum FSH and LH were below the detection limit of 1 mIU/mL. The enzymatic activity was higher in ADX than in sham-operated rats. Epididymal zinc level increased whereas copper level decreased in ADX rats compared to the sham-operated. CONCLUSION: Adrenalectomy leads to degeneration of caput and cauda epididymidis epithelial cells as a result of decreased supply of testosterone. 展开更多
关键词 ADRENALECTOMY Acid Phosphatase Alkaline Phosphatase Animals Arylsulfatases Cholesterol Comparative Study Copper EPIDIDYMIS Follicle Stimulating Hormone L-Lactate Dehydrogenase Leucyl Aminopeptidase Luteinizing Hormone Male Organ Size RATS Rats Sprague-Dawley Reference Values Research Support Non-U.S. Gov't TESTOSTERONE Time Factors Zinc
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Antifertility effects of methanolic pod extract of Albizzia lebbeck (L.) Benth in male rats 被引量:1
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作者 R. S. Gupta J. B. S.Kachhawa R. Chaudhary 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第2期155-159,共5页
Aim: To evaluate the antifertility activity of the methanolic pod extract of Albizzia lebbeck (L.) Benth in male albino rats. Methods: The methanolic pod extract of Albizzia lebbeck was administrated orally for 60 day... Aim: To evaluate the antifertility activity of the methanolic pod extract of Albizzia lebbeck (L.) Benth in male albino rats. Methods: The methanolic pod extract of Albizzia lebbeck was administrated orally for 60 days at 50, 100 and 200 mg·kg-1·day-1 to male albino rats. Sperm motility and density in cauda epididymides were assessed. Biochemical and histological analysis were performed in blood samples and reproductive organs. Results: A. lebbeck pod extract brought about a significant decrease in the weights of testis, seminal vesicles, epdidymis and ventral prostate. The sperm motility and density were significantly reduced. There was a marked reduction in the numbers of primary spermatocytes, secondary spermatocytes and spermatids. The Sertoli cell count as well as its cross sectional surface area were significantly decreased. The Leydig cell nuclear area and the number of mature Leydig celis were also significantly decreased. The protein, glycogen and cholesterol content of the testis, the fructose in the seminal vesicles and protein in the epididymis were significantly decreased. The RBC and WBC counts, haemoglobin, haematocrit and blood sugar were within the normai range. Conclusion: The methanolic extract of A. lebbeck pods causes spermatogenic arrest in male albino rats. 展开更多
关键词 Albizzia lebbeck sertoli celis SPERMATOGONIA SPERMATOCYTES leydig celis
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Safety evaluation of long-term vas occlusion with styrene maleic anhydride and its non-invasive reversal on accessory reproductive organs in langurs 被引量:1
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作者 B.Manivannan S.S.Bhande +2 位作者 S.Panneerdoss S.Sriram N.K.Lohiya 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第2期195-204, ,共10页
Aim:To evaluate the safety of the long term vas occlusion with styrene maleic anhydride (SMA) and its non-invasive reversal at the level of accessory reproductive glands (ARGs) in langurs.Methods:The morphology of sem... Aim:To evaluate the safety of the long term vas occlusion with styrene maleic anhydride (SMA) and its non-invasive reversal at the level of accessory reproductive glands (ARGs) in langurs.Methods:The morphology of seminal vesicle and ventral prostate was evaluated by light as well as transmission electron microscopy.Serum clinical chemistry and urine albumin were evaluated in an autoanalyzer using reagent kits.Fructose,acid phosphatase and zinc in the seminal plasma were evaluated spectrophotometrically according to the WHO manual.Serum testosterone, prostate specific antigen and sperm antibodies were evaluated by enzyme-linked immunosorbent assays (ELISA) using reagent kits and hematology was estimated according to standard procedures.Results:The morphological features and secretory activity of the seminal vesicle and prostate were normal as evidenced by the presence of well- developed mitochondria,rough endoplasmic reticulum,Golgi bodies,secretory granules and normal nuclear charac- teristics throughout the course of investigation.Serum testosterone and prostate specific antigen remained unaltered and serum antisperm antibodies level presented negative titres.Urine albumin was nil.Total red blood corpuscles (RBC),white blood corpuscles (WBC),hemoglobin (Hb) and red cell indices,serum protein,glucose,cholesterol, creatinine,creatine kinase (CK),serum glutamate oxalate transaminase (SGOT),serum glutamate pyruvate transami- nase (SGPT),lactate dehydrogenase (LDH),bilirubin,urea,triglycerides and high-density lipoprotein (HDL) did not show appreciable changes following vas occlusion and after its non-invasive reversal.Although fructose,acid phos- phatase (ACP) and zinc in the seminal plasma showed a significant reduction following vas occlusion,it could not be related to the morphology of seminal vesicle and prostate.Conclusion:SMA vas occlusion and its non-invasive reversal do not damage the accessory reproductive organs. 展开更多
关键词 langurs male contraception poly styrene maleic anhydride
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Influence of CdS Nano Additives on the Thermal Conductivity of Poly(vinyl chloride)/CdS Nanocomposites 被引量:1
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作者 Dinesh Patidar Narendra Sahai Saxena 《Advances in Nanoparticles》 2013年第1期11-15,共5页
PVC/CdS nanocomposites have been prepared by solution casting method taking 2, 4, 6 and 8 wt% of CdS nanoparticles. PVC/CdS nanocomposites were characterized through TEM measurement. The measurement of effective therm... PVC/CdS nanocomposites have been prepared by solution casting method taking 2, 4, 6 and 8 wt% of CdS nanoparticles. PVC/CdS nanocomposites were characterized through TEM measurement. The measurement of effective thermal conductivity of PVC/CdS nanocomposites has also been done using transient plane source (TPS) method. The effects of concentration of CdS nanoparticles and temperature on the effective thermal conductivity of polymer PVC/CdS nanocomposites have been studied. The variation of effective thermal conductivity with the concentration of filler particles and temperature has also been discussed in terms of dispersion of filler particles into polymer matrix and phonon scattering mechanism, respectively. 展开更多
关键词 Polymer NANOCOMPOSITE Effective Thermal CONDUCTIVITY Transient PLANE Source Method
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Prediction of Effective Elastic Modulus of Biphasic Composite Materials 被引量:2
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作者 Anupama Upadhyay Ramvir Singh 《Modern Mechanical Engineering》 2012年第1期6-13,共8页
Two semi-empirical approaches for prediction of elastic modulus of biphasic composites have been proposed. Developed relations are for pore free matrix and pore free filler and found to depend on nonlinear contributio... Two semi-empirical approaches for prediction of elastic modulus of biphasic composites have been proposed. Developed relations are for pore free matrix and pore free filler and found to depend on nonlinear contribution of volume fraction of constituents as well as ratio of elastic properties of individual phases. These relations are applied for the calculation of effective elastic modulus mainly for Al2O3-NiAl, SiC-Al, Alumina-Zirconia, Al-Al2O3, W-glass and Flax-Resin composite materials. Theoretical predictions using developed relations are compared with experimental data. It is found that the predicted values of effective elastic modulus using modified relations are quite close to the experimental results. 展开更多
关键词 ELASTIC MODULUS Composite Material Matrix-Inclusion
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Evaluation of Morphological Effect on Thermal and Mechanical Performance of PS/PMMA/CdS Nanocomposite Systems 被引量:1
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作者 Vishal Mathur Kananbala Sharma 《Advances in Nanoparticles》 2013年第3期205-216,共12页
In the present paper an effort has been made to investigate effect of dispersion of CdS nanoparticles on the thermal and mechanical properties of PS/PMMA blends. Samples have been prepared through dispersion of CdS na... In the present paper an effort has been made to investigate effect of dispersion of CdS nanoparticles on the thermal and mechanical properties of PS/PMMA blends. Samples have been prepared through dispersion of CdS nanoparticles (prepared separately) during solution casting blend fabrication processing. These nanocomposites samples are structurally characterized through Wide angle X-ray Scattering (WAXS) and Small Angle X-ray Scattering (SAXS) techniques. Scanning Electron Microscopy (SEM) analyses of these samples have been carried out in lieu of surface morphological characterization. The measurements of glass transition temperature and stress-strain analyses have been performed through Dynamic Mechanical Analyzer (DMA). The thermal conductivity of nanocomposite samples has been determined using Hot Disk Thermal Constants Analyzer. The study shows that the incorporation of dispersed CdS nanoparticles in PS/PMMA blend matrix significantly alter their glass transition behaviour, thermal conductivity and tensile properties. 展开更多
关键词 THERMAL CONDUCTIVITY CDS NANOCOMPOSITES Glass Transition Temperature TENSILE Properties
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