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1.
Nanotechnology ; 24(21): 215401, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23619430

RESUMO

In the present investigation, we report on the thermoelectric properties of PbSe0.5Te0.5: x (PbI2) from room temperature to 625 K. High-resolution transmission electron micrographs of the samples reveal endotaxial nanostructures embedded in a PbSe0.5Te0.5 matrix. The combined effect of mass fluctuation and nanostructures reduces the thermal conductivity to a great extent compared to PbTe and PbSe, without affecting the carrier mobility. As a result, a thermoelectric figure of merit with a value of 1.5 is achieved at 625 K. This value is significantly higher than that of the available state-of-the-art n-type materials.


Assuntos
Chumbo/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Compostos de Selênio/química , Semicondutores , Campos Eletromagnéticos , Temperatura Alta , Teste de Materiais , Tamanho da Partícula
2.
Osteoporos Int ; 22(12): 3013-27, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21225417

RESUMO

UNLABELLED: The effect of quercetin C-glucoside (QCG) on osteoblast function in vitro and bone formation in vivo was investigated. QCG supplementation promoted peak bone mass achievement in growing rats and new bone formation in osteopenic rats. QCG has substantial oral bioavailability. Findings suggest a significant bone anabolic effect of QCG. INTRODUCTION: Recently, we showed that extracts of Ulmus wallichiana promoted peak bone mass achievement in growing rats and preserved trabecular bone mass and cortical bone strength in ovariectomized (OVx) rats. 3,3',4',5,7-Pentahydroxyflavone-6-C-ß-D-glucopyranoside, a QCG, is the most abundant bioactive compound of U. wallichiana extract. We hypothesize that QCG exerts bone anabolic effects by stimulating osteoblast function. METHODS: Osteoblast cultures were harvested from rat calvaria and bone marrow (BM) to study differentiation and mineralization. In vivo, growing female Sprague Dawley rats and OVx rats with osteopenia were administered QCG (5.0 or 10.0 mg kg(-1) day(-1)) orally for 12 weeks. Efficacy was evaluated by examining changes in bone microarchitecture using histomorphometric and microcomputed tomographic analyses and by determination of new bone formation by fluorescent labeling of bone. Plasma and BM levels of QCG were determined by high-performance liquid chromatography. RESULTS: QCG was much more potent than quercetin (Q) in stimulating osteoblast differentiation, and the effect of QCG was not mediated by estrogen receptors. In growing rats, QCG increased BM osteoprogenitors, bone mineral density, bone formation rate, and cortical deposition. In osteopenic rats, QCG treatment increased bone formation rate and improved trabecular microarchitecture. Comparison with the sham group (ovary intact) revealed significant restoration of trabecular bone in osteopenic rats treated with QCG. QCG levels in the BM were ~50% of that of the plasma levels. CONCLUSION: QCG stimulated modeling-directed bone accrual and exerted anabolic effects on osteopenic rats by direct stimulatory effect on osteoprogenitors likely due to substantial QCG delivery at tissue level following oral administration.


Assuntos
Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/tratamento farmacológico , Glucosídeos/isolamento & purificação , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Quercetina/análogos & derivados , Animais , Medula Óssea/química , Cromatografia Líquida , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Glucosídeos/química , Glucosídeos/farmacologia , Membro Posterior , Ovariectomia , Quercetina/sangue , Quercetina/química , Quercetina/farmacologia , Ratos , Ratos Sprague-Dawley , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Microtomografia por Raio-X
3.
Indian J Ophthalmol ; 67(1): 64-68, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30574895

RESUMO

PURPOSE: To report results of a novel technique for sutureless, glueless intrascleral fixation of three-piece posterior chamber intraocular lens (IOL) using 26-G needle for management of aphakia. METHODS: In this prospective series, 30 eyes of 20 patients with aphakia, subluxated IOL, or crystalline lens were included. 26-G-needle-guided intrascleral fixation of three-piece posterior chamber IOL was performed according to the described technique. The patients were evaluated on day 2, 1 week, 6 weeks, and 3 months postoperatively for change in best-corrected visual acuity (BCVA), intraocular pressure (IOP), IOL centration, and any other complications. The postoperative tilt of the IOL was indirectly measured by determining the lenticular astigmatism which in turn was calculated by the difference between net corneal astigmatism and refractive astigmatism. Paired t-test was used to determine the significance of any association between the preoperative and postoperative BCVA and IOP. P < 0.05 was considered significant. RESULTS: Of 30 eyes (n = 30 patients), 18 were surgical aphakia, 6 traumatic aphakia, 5 subluxated IOL, and 1 ectopia lentis (Marfan syndrome). The mean preoperative BCVA was 1.37 ± 0.37 (logMAR) and postoperative BCVA at 3 months was 0.37 ± 0.29 (logMAR). A significant improvement in the mean BCVA (P < 0.05) was observed after the procedure. The mean IOP preoperatively was 13.33 ± 4.18 and postoperatively at 3 months was 12.82 ± 3.97 (P > 0.05), which was not significant. None of the eyes developed any intraoperative and postoperative complications. The IOLs had appropriate centration and stability. CONCLUSION: We have developed this new technique for intrascleral IOL fixation which is quite simple, cost-effective, minimally invasive, neither requires glue nor suture and gives consistent outcome.


Assuntos
Afacia Pós-Catarata/cirurgia , Implante de Lente Intraocular/métodos , Esclera/cirurgia , Procedimentos Cirúrgicos sem Sutura/métodos , Acuidade Visual , Adesivos , Afacia Pós-Catarata/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Theriogenology ; 110: 52-60, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29334660

RESUMO

Accurate and efficient detection of estrus is one of the major constraints for exploitation of the production potential of buffalo owing to its poor manifestation of estrus signs, seasonal differences in expression and higher incidences of silent estrus (29%). The current study focused on identification of estrus specific candidate proteins in saliva of buffaloes. Estrus was detected based on behavioral signs in response to the teaser and changes in reproductive organs and confirmed by per-rectal examination, trans-rectal USG of reproductive organs, cervico-vaginal mucus characteristics and blood serum progesterone estimation. Day of onset of estrus was considered as day 0 and day -3, +3, +10 were considered as proestrus, metestrus and diestrus stage of the estrous cycle respectively. A total of 19 animals and their 38 estrous cycles (two from each) were included in this study. Saliva was collected from these animals during different stages of estrous cycle. Out of these, 08 animals were selected for global proteome analysis of saliva using in-solution digestion and nano-LC-MS/MS. A total of 275, 371, 304 and 565 proteins were identified with ≥2 peptides during proestrus, estrus, metestrus and diestrus stages of estrous cycle. Among the identified proteins 31, 62, 32 and 104 proteins were found specific to proestrus, estrus, metestrus and diestrus stage of the estrous cycle. Few salivary proteins such as Cullin-associated NEDD8-dissociated protein 1, Heat shock 70 kDa protein 1A, 17-beta-hydroxysteroid dehydrogenase type 1, Inhibin beta A chain, testin were identified as estrus specific and are important for estrus physiology. Taken together, these estrus specific proteins could be considered as the candidate biomarker for detection and confirmation of estrus in buffalo after thorough validation.


Assuntos
Búfalos/metabolismo , Ciclo Estral/metabolismo , Proteoma/análise , Proteômica/métodos , Saliva/química , Animais , Feminino , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/veterinária , Espectrometria de Massas/métodos , Espectrometria de Massas/veterinária , Saliva/metabolismo
5.
Talanta ; 19(5): 706-7, 1972 May.
Artigo em Inglês | MEDLINE | ID: mdl-18961104

RESUMO

The complexation of In(III) and U(VI) with thiodipropionic acid has been investigated polarographically in water and water-methanol solutions at 30 +/- 0.1 degrees . All the chelates belong to polaro-graphically reversible systems. With indium(III), complexes with metal to ligand ratios of 1:1, 1:2, 1:3 and 1:4 are found at pH 4.8. Uranium(VI) is found to form three successive complexes with metal to ligand ratios of 1:1,1:2 and 1:3 in 0.1M HCl, with 0.1M KCl as supporting electrolyte.

6.
Anim Reprod Sci ; 72(3-4): 175-83, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12137980

RESUMO

The present study was conducted to observe the effect of initial freezing temperature on subsequent survival and acrosomal integrity of Malpura and Bharat Merino ram spermatozoa during post-thawing incubation. Semen samples were diluted in TEST-yolk-glycerol extender, loaded in 0.25 ml straws and cooled down to -25, -75 or -125 degrees C freezing temperature using a programmable cell freezer. Computer assisted sperm analysis and acrosomal integrity of thawed samples were assessed after thawing and at hourly intervals during incubation at 37 degrees C for 4 h. The percentage of motile cells in samples frozen at -125 degrees C were 80.3 and 63.7 after post-thawing and -thawing incubation, compared to 75.9 and 39.7 at -25 degrees C or 73.9 and 51.8 at -75 degrees C temperatures, respectively. The spermatozoa with normal acrosome were also significantly, respectively, higher in samples frozen at -125 degrees C, compared to -25 and -75 degrees C temperatures. There were no significant breed variations on percentage of motile, percentage of rapidly motile cells, percentage of normal acrosomes, curvilinear velocity and lateral head displacement except straight line velocity and average path velocity of spermatozoa. The results indicated that -125 degrees C initial freezing temperature conferred the best cryopreserving ability to ram spermatozoa for post-thawing thermoresistance test compared to -25 or -75 degrees C freezing temperature.


Assuntos
Acrossomo/ultraestrutura , Congelamento , Nitrogênio , Preservação do Sêmen/veterinária , Ovinos , Motilidade dos Espermatozoides , Animais , Criopreservação/métodos , Criopreservação/veterinária , Temperatura Alta , Masculino , Preservação do Sêmen/métodos , Soluções
7.
ACS Appl Mater Interfaces ; 6(6): 3995-4004, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24575978

RESUMO

Motivated by the theoretically predicted Zn resonant states in the conduction band of PbTe, in the present work, we investigated the effect of Zn substitution on the thermoelectric properties in I-doped n-type PbTe. The room temperature thermopower values show good agreement with the theoretical Pisarenko plot of PbTe up to a carrier concentration of 4.17 × 10(19) cm(-3); thus, the presence of Zn resonance levels is not observed. Because of the low solubility of Zn in PbTe, a second phase of coherent ZnTe nanostructures is observed within the PbTe host matrix, which is found to reduce the lattice thermal conductivity. The reduced lattice thermal conductivity in PbTe by ZnTe nanostructures leads to notable enhancement in the figure of merit with a maximum value of 1.35 at 650 K. In contrast to the recent literature, the carrier mobility is not found to be affected by the band offset between ZnTe nanostructures and PbTe. This is explained by the quantum tunneling of the charge carrier through the narrow offset barrier and depletion width and coherent nature of the interface boundary between the two phases, i.e., ZnTe and PbTe.

8.
Trop Anim Health Prod ; 35(3): 249-57, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12797414

RESUMO

The Garole is a prolific but less well known and rare breed of small sheep found in the hot and humid Sunderban region of West Bengal. An ability to breed throughout the year and to graze in knee-deep water, resistance to foot rot and a strong mothering instinct are some of the special features of this breed. Garole rams could provide germplasm to incorporate prolificacy traits by artificial insemination of the nonprolific sheep breeds found in abundance in the semi-arid and arid tropical climates of India. The aim of the present study was to evaluate the semen production by Garole rams maintained in a semi-arid climate for three years and to objectively assess their semen quality by a computer-assisted sperm analysis technique. The donor rams were randomly selected each year from the original flock procured from their natural habitat or from the offspring born at the Institute farm. Semen was collected weekly for three weeks each autumn for three consecutive years from 8 rams each year. The overall means (SD) of the traits that did not differ significantly with age or year were volume, concentration, curvilinear velocity, average path velocity, amplitude of lateral head displacement, beat frequency, motility and the percentages of rapid motile sperms and of slow motile sperms. The age of the rams had a significant effect (p<0.05) on the straight-line velocity but this was not significantly affected by the length of exposure to the semi-arid climate. However, the age and year had significant effects (p<0.05) on linearity, straightness and the percentage of medium motile sperms. It was concluded that Garole rams are capable of producing good-quality semen even after a prolonged period of exposure to a semi-arid tropical climate.


Assuntos
Ovinos/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Clima Tropical , Animais , Autoanálise/veterinária , Índia , Masculino , Contagem de Espermatozoides/veterinária
11.
New Delhi; B. Jain; 1977. 28 p.
Monografia em Inglês | HomeoIndex (homeopatia) | ID: hom-9658
12.
New Delhi; B. Jain; 1977. 21 p.
Monografia em Inglês | HomeoIndex (homeopatia) | ID: hom-9660
13.
New Delhi; B. Jain; 1987. 23 p.
Monografia em Inglês | HomeoIndex (homeopatia) | ID: hom-9661
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