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1.
J Dent Res ; 103(7): 712-722, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38766865

RESUMO

Inflammation and loss of articular cartilage are considered the major cause of temporomandibular joint osteoarthritis (TMJOA), a painful condition of the temporomandibular joint (TMJ). To determine the cause of TMJ osteoarthritis in these patients, synovial fluid of TMJOA patients was compared prior to and after hyaluronic lavage, revealing substantially elevated levels of interleukin (IL) 1ß, reactive oxidative stress (ROS), and an overload of Fe3+ and Fe2+ prior to lavage, indicative of ferroptosis as a mode of chondrocyte cell death. To ask whether prolonged inflammatory conditions resulted in ferroptosis-like transformation in vitro, we subjected TMJ chondrocytes to IL-1ß treatment, resulting in a shift in messenger RNA sequencing gene ontologies related to iron homeostasis and oxidative stress-related cell death. Exposure to rat unilateral anterior crossbite conditions resulted in reduced COL2A1 expression, fewer chondrocytes, glutathione peroxidase 4 (GPX4) downregulation, and 4-hydroxynonenal (4-HNE) upregulation, an effect that was reversed after intra-articular injections of the ferroptosis inhibitor ferrostatin 1 (Fer-1). Our study demonstrated that ferroptosis conditions affected mitochondrial structure and function, while the inhibitor Fer-1 restored mitochondrial structure and the inhibition of hypoxia-inducible factor 1α (HIF-1α) or the transferrin receptor 1 (TFRC) rescued IL-1ß-induced loss of mitochondrial membrane potential. Inhibition of HIF-1α downregulated IL-1ß-induced TFRC expression, while inhibition of TFRC did not downregulate IL-1ß-induced HIF-1α expression in chondrocytes. Moreover, inhibition of HIF-1α or TFRC downregulated the IL-1ß-induced MMP13 expression in chondrocytes, while inhibition of HIF-1α or TFRC rescued IL-1ß-inhibited COL2A1 expression in chondrocytes. Furthermore, upregulation of TFRC promoted Fe2+ entry into chondrocytes, inducing the Fenton reaction and lipid peroxidation, which in turn caused ferroptosis, a disruption in chondrocyte functions, and an exacerbation of condylar cartilage degeneration. Together, these findings illustrate the far-reaching effects of chondrocyte ferroptosis in TMJOA as a mechanism causing chondrocyte death through iron overload, oxidative stress, and articular cartilage degeneration and a potential major cause of TMJOA.


Assuntos
Condrócitos , Ferroptose , Subunidade alfa do Fator 1 Induzível por Hipóxia , Interleucina-1beta , Osteoartrite , Estresse Oxidativo , Receptores da Transferrina , Transtornos da Articulação Temporomandibular , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ratos , Receptores da Transferrina/metabolismo , Osteoartrite/metabolismo , Transtornos da Articulação Temporomandibular/metabolismo , Masculino , Humanos , Ratos Sprague-Dawley , Inflamação , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Articulação Temporomandibular/metabolismo , Articulação Temporomandibular/patologia , Cicloexilaminas/farmacologia , Cartilagem Articular/metabolismo , Colágeno Tipo II , Espécies Reativas de Oxigênio/metabolismo , Feminino , Aldeídos , Fenilenodiaminas
3.
J Forensic Odontostomatol ; 38(2): 12-21, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33174534

RESUMO

AIM: To analyze the morphological parameters of palatal rugae in a population of Maharashtrian ancestry. MATERIAL AND METHODS: This study was conducted on 1000 subjects of Maharashtrian ancestry with at least 3 generations on the mother's and father's side. Their palatal impressions were obtained with alginate and the casts were analyzed for length, shape and direction of palatal rugae. RESULTS: Our results showed that the most predominant rugae were primary followed by secondary and fragmentary with significant differences between them. The most prevalent rugae shapes found were straight followed by wavy followed by curved with significant differences between them. According to direction, forward rugae were significantly higher than perpendicular rugae and backward rugae. CONCLUSION: The rugae are considered to have population specific configurations. This baseline data of patterns of palatal rugae in a sample of Maharashtrian ancestry may serve `as an accessory tool' for population identification in Forensic Dentistry.


Assuntos
Mucosa Bucal , Palato , Estudos Transversais , Pai , Feminino , Odontologia Legal , Humanos , Masculino
4.
PLoS One ; 15(6): e0234053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484834

RESUMO

The efficient (site-specific) management of soil nutrients is possible by understanding the spatial variability in distribution of phyto-available nutrients (here after called available nutrients) and identifying the soil management zones (MZs) of agricultural landscapes. There is need for delineating soil MZs of agricultural landscapes of the world for efficient management of soil nutrients in order to obtain sustainability in crop yield. The present study was, therefore, undertaken to understand the spatial distribution pattern of available micronutrients (zinc (Zn), boron (B), iron (Fe), manganese (Mn) and copper (Cu)), available sulphur (S), and soil properties (soil acidity (pH), electrical conductivity (EC) and organic carbon (SOC) content) in soils of intensively cultivated Indo-Gangetic Plain (IGP) of India and to delineate soil MZs for efficient management of soil nutrients. Totally, 55101 soil samples from 0-15 cm depth were obtained from 167 districts of IGP during 2014 to 2017 and were analysed for different soil parameters. Soil pH, EC and SOC content varied from 4.44 to 9.80, 0.02 to 2.13 dS m-1 and 0.10 to 1.99%, respectively. The concentration of available Zn, B, Fe, Mn, Cu and S varied from 0.01 to 3.27, 0.01 to 3.51, 0.19 to 55.7, 0.05 to 49.0, 0.01 to 5.29 and 1.01 to 108 mg kg-1, respectively. Geostatistical analysis resulted in varied distribution pattern of studied soil parameters with moderate to strong spatial dependence. The extent (% area) of nutrient deficiencies in IGP followed the order: S > Zn > B > Mn > Cu > Fe. Principal component analysis and fuzzy c-means clustering produced six distinctly different soil MZs of IGP for implementation of zone-specific soil nutrient management strategies for attaining sustainability in crop yield. The developed MZ maps could also be utilized for prioritization and rationalization of nutrients supply in IGP of India.


Assuntos
Monitoramento Ambiental , Micronutrientes/análise , Solo/química , Análise Espacial , Enxofre/análise , Índia , Chuva , Estatística como Assunto
5.
Med Oral Patol Oral Cir Bucal ; 25(5): e626-e633, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32388518

RESUMO

BACKGROUND: Randomized controlled trials (RCTs) provide the highest level of evidence and are likely to influence clinical decision-making. This study evaluated the reporting quality of RCT abstracts on drug therapy of periodontal disease and assessed the associated factors. MATERIAL AND METHODS: The Pubmed database was searched for periodontal RCTs published in Science Citation Indexed (SCI) dental journals from 2010/01/01 to 2019/07/17. Information was extracted from the abstracts according to a modified Consolidated Standards of Reporting Trials (CONSORT) guideline checklist. The data was analyzed using descriptive statistical analysis and the statistical associations were examined using the linear regression analysis (P<0.05). RESULTS: This study retrieved 1715 articles and 249 of them were finally included. The average overall CONSORT score was 15.6 ± 3.4, which represented 40.9% (±0.6) of CONSORT criteria filling. The reporting rate of some items (trial design, numbers analyzed, confidence intervals, intention-to-treat analysis or per-protocol analysis, harms, registration) was less than 30%. The adequate reporting rate of some items (participants, randomization, numbers analyzed, confidence intervals, intention-to-treat analysis or per protocol analysis) was no more than 4%. None of the abstracts reported funding. According to the multivariable linear regression results, number of authors (P=0.030), word count (P<0.001), continent (P=0.003), structured format (P<0.001), type of periodontal disease (P<0.001) and international collaboration (P=0.023) have a significant association with reporting quality. CONCLUSIONS: The quality of RCT abstracts on drug therapy of periodontal disease in SCI dental journals remained suboptimal. More efforts should be made to improve RCT abstracts reporting quality.


Assuntos
Indexação e Redação de Resumos , Publicações Periódicas como Assunto , Doenças Periodontais , Ensaios Clínicos Controlados Aleatórios como Assunto , Lista de Checagem , Humanos , Projetos de Pesquisa
6.
Neural Netw ; 126: 191-217, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32248008

RESUMO

We examine the efficiency of Recurrent Neural Networks in forecasting the spatiotemporal dynamics of high dimensional and reduced order complex systems using Reservoir Computing (RC) and Backpropagation through time (BPTT) for gated network architectures. We highlight advantages and limitations of each method and discuss their implementation for parallel computing architectures. We quantify the relative prediction accuracy of these algorithms for the long-term forecasting of chaotic systems using as benchmarks the Lorenz-96 and the Kuramoto-Sivashinsky (KS) equations. We find that, when the full state dynamics are available for training, RC outperforms BPTT approaches in terms of predictive performance and in capturing of the long-term statistics, while at the same time requiring much less training time. However, in the case of reduced order data, large scale RC models can be unstable and more likely than the BPTT algorithms to diverge. In contrast, RNNs trained via BPTT show superior forecasting abilities and capture well the dynamics of reduced order systems. Furthermore, the present study quantifies for the first time the Lyapunov Spectrum of the KS equation with BPTT, achieving similar accuracy as RC. This study establishes that RNNs are a potent computational framework for the learning and forecasting of complex spatiotemporal systems.


Assuntos
Algoritmos , Bases de Dados Factuais/tendências , Aprendizado de Máquina/tendências , Redes Neurais de Computação , Previsões , Humanos , Fatores de Tempo
7.
3 Biotech ; 7(1): 70, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28452016

RESUMO

Costus pictus, belonging to the family Costaceae, is one of the valuable medicinal plants with its anti-diabetic property. Despite ever-increasing demand from the pharmaceutical industry, this species is being less exploited at molecular level. Hence, an effort has been made in the present study to characterize the 15 accessions of C. pictus collected from different geographical regions of India through random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) markers. A total of 25 RAPD and 20 ISSR primers were used in the present study. The RAPD analysis generated 343 loci, of which 124 were polymorphic with an average of 4.96 loci per primer. While, ISSR primers produced 177 loci, of which 77 were polymorphic with an average of 3.85 loci per primer. The similarity coefficients ranged from 0.86-0.99, 0.84-0.95 and 0.86-0.96 for RAPD, ISSR and combined RAPD-ISSR, respectively. The UPGMA dendrogram generated using these data showed low level of divergence among the accessions from South and West regions. Further, accession-specific bands were also revealed by RAPD and ISSR markers which might be contributed to specific trait. This investigation was an understanding of genetic variation within the C. pictus accessions. The present finding indicates that both the marker tools RAPD and ISSR combined or individually can be used in determining the genetic relationship between the accessions. It may be concluded that data of hereditary differences appeared among the C. pictus accessions could be utilized for their conservation and reproducing programs.

8.
Iran J Vet Res ; 18(4): 243-248, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29387095

RESUMO

The present study was undertaken to assess the effect of different chemical activators along with 6-DMAP on in vitro matured caprine oocytes. From 4332 ovaries, 14235 cumulus oocyte complexes (COCs) were collected which were matured in TCM-199 medium containing follicle stimulating hormone (FSH) (5 µg/ml), Leutinizing hormone (LH) (10 µg/ml), oestradiol-17ß (1 µg/ml) supplemented with 10% fetal bovine serum, 10% follicular fluid and 3 mg/ml bovine serum albumin (BSA) at 38.5°C and 5% CO2 in an incubator under humidified air for 27 h. In group 1 (control), 3117 in vitro matured oocytes were co incubated with sperms for 18 h in ferttalp medium. In group 2, 3563 in vitro matured oocytes were activated with 7% ethanol for 5-7 min followed by treatment with 2.0 mM DMAP for 4 h in mCR2aa medium. In group 3, 3109 in vitro matured oocytes were activated with 5 µM ionomycin for 5-7 min followed by treatment with 2.0 mM DMAP for 4 h in mCR2aa medium. In group 4, 3455 in vitro matured oocytes were activated with 5 µM calcium ionophore for 5-7 min followed by treatment with 2.0 mM DMAP for 4 h in mCR2aa medium. Oocytes were cultured in 50 µL drops of research vitro cleave (RVCL) medium for embryo development. The cleavage rate, morula and blastocyst production in group 1, 2, 3 and 4 were 26.07 ± 2.37%, 14.91 ± 2.91 & 1.45 ± 0.71%, 49.57 ± 3.79%, 20.07 ± 2.38% & 5.29 ± 1.42%, 50.18 ± 3.59%, 15.26 ± 2.87% & 1.85 ± 0.72% and 80.26 ± 2.30%, 35.33 ± 2.67 & 7.10 ± 0.89%, respectively. These results indicated that the activation of in vitro matured oocytes by 5 µM calcium ionophore for 5-7 min followed by treatment with 2.0 mM DMAP for 4 h is most favorable for parthenogenetic caprine embryos production.

9.
Transl Psychiatry ; 6: e870, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27529678

RESUMO

Patients with bipolar disorder (BD) have a high prevalence of comorbid medical illness. However, the mechanisms underlying these comorbidities with BD are not well known. Certain genetic variants may have pleiotropic effects, increasing the risk of BD and other medical illnesses simultaneously. In this study, we evaluated the association of BD-susceptibility genetic variants with various medical conditions that tend to co-exist with BD, using electronic health records (EHR) data linked to genome-wide single-nucleotide polymorphism (SNP) data. Data from 7316 Caucasian subjects were used to test the association of 19 EHR-derived phenotypes with 34 SNPs that were previously reported to be associated with BD. After Bonferroni multiple testing correction, P<7.7 × 10(-5) was considered statistically significant. The top association findings suggested that the BD risk alleles at SNP rs4765913 in CACNA1C gene and rs7042161 in SVEP1 may be associated with increased risk of 'cardiac dysrhythmias' (odds ratio (OR)=1.1, P=3.4 × 10(-3)) and 'essential hypertension' (OR=1.1, P=3.5 × 10(-3)), respectively. Although these associations are not statistically significant after multiple testing correction, both genes have been previously implicated with cardiovascular phenotypes. Moreover, we present additional evidence supporting these associations, particularly the association of the SVEP1 SNP with hypertension. This study shows the potential for EHR-based analyses of large cohorts to discover pleiotropic effects contributing to complex psychiatric traits and commonly co-occurring medical conditions.


Assuntos
Transtorno Bipolar/genética , Doenças Cardiovasculares/genética , Pleiotropia Genética , Doenças Metabólicas/genética , Doenças do Sistema Nervoso/genética , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/genética , Transtorno Bipolar/epidemiologia , Canais de Cálcio Tipo L/genética , Doenças Cardiovasculares/epidemiologia , Moléculas de Adesão Celular/genética , Comorbidade , Registros Eletrônicos de Saúde , Feminino , Estudo de Associação Genômica Ampla , Cefaleia/epidemiologia , Cefaleia/genética , Humanos , Hipertensão/epidemiologia , Hipertensão/genética , Masculino , Doenças Metabólicas/epidemiologia , Pessoa de Meia-Idade , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/genética , Doenças do Sistema Nervoso/epidemiologia , Polimorfismo de Nucleotídeo Único , População Branca
10.
Reprod Domest Anim ; 51(4): 611-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27170442

RESUMO

The aim of the present investigation was to study the effect of calcium ionophore activation on blastocyst production following intracytoplasmic sperm injection (ICSI) in in vitro-matured Caprine oocytes. A total of 470 in vitro-matured oocytes were selected and randomly divided in to three groups. Cumulus oocyte complexes (COCs) recovered by slicing the Caprine ovaries were matured in TCM199 supplemented with 10% foetal bovine serum (FBS) + 10% follicular fluid + FSH (5 µg/ml) + LH (10 µg/ml) + estradiol (1 µg/ml) + EGF (10 ng/ml) + BSA (3 mg/ml) for 27 h in humidified atmosphere at 38.5°C with 5% CO2 in CO2 incubator. After 27 h of culture, selected COCs (n = 470) were separated from cumulus cells by treating with 0.1% hyaluronidase enzyme and passing repeatedly through a fine pipette and randomly divided into three groups. In group 1, (n = 168) matured oocytes were injected with injection micropipette without sperm as control. In group 2, (n = 152) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette. In group 3, (n = 150) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette and then activated with 5 µm Ca ionophore for 5 min. The oocytes of all groups were then culture in RVCL media for embryo development. The cleavage rate was observed after 48-72 h of injection. The cleavage rate and blastocyst production in group 1, 2 and 3 were 0.00 and 0.00, 18.42 and 3.57 and 61.33% and 16.30%, respectively. The result indicated that mechanical activation failed to induce cleavage in in vitro-matured Caprine oocytes, whereas chemical activation of intracytoplasmic sperm-injected in vitro-matured Caprine oocytes showed significantly higher cleavage rate and blastocyst production as compare to non-activated oocytes.


Assuntos
Ionóforos de Cálcio/farmacologia , Cabras , Injeções de Esperma Intracitoplásmicas/veterinária , Animais , Blastocisto , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Oócitos/fisiologia
11.
Osteoporos Int ; 25(10): 2453-63, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25027107

RESUMO

SUMMARY: The combination of cytokines present in the circulation of patients with active rheumatoid arthritis might contribute to the generalized bone loss that commonly occurs in these patients, by directly inhibiting osteoblast proliferation and differentiation, but especially by enhancing endogenous cytokine (i.e., receptor activator of nuclear factor-kappa B ligand (RANKL) and interleukin-6 (IL)-6) production by osteoblasts, thereby stimulating osteoclastogenesis. INTRODUCTION: Generalized bone loss, as occurs in patients with rheumatoid arthritis (RA), is related to elevated levels of circulating cytokines. Individual cytokines have deleterious effects on proliferation and differentiation of osteoblast cell lines, but little is known about the effect of the interaction between inflammatory factors in the circulation of patients with active RA on human osteoblast function, including their communication towards other bone cells. We investigated whether serum from patients with active RA enhances cytokine production by osteoblasts, thereby effectively altering osteoblast-stimulated osteoclastogenesis. METHODS: Serum was obtained from 20 patients with active RA (active RA sera) and from the same patients in clinical remission (remission RA sera). To determine osteoclastogenesis, RA serum-pretreated primary human osteoblast cultures were established in direct contact with human osteoclast precursors in the presence or absence of osteoprotegerin (OPG) or IL-6 inhibitor. RESULTS: Compared to remission RA sera, active RA sera inhibited osteoblast proliferation and differentiation in vitro as demonstrated by a reduced DNA content and gene expression of KI-67, collagen type 1, osteopontin, and osteocalcin. Active RA sera inhibited OPG expression and enhanced RANKL and IL-6 expression but did not alter IL-8 expression in osteoblasts. IL-1ß, IL-17, and tumor necrosis factor-α (TNF-α) expression were undetectable. In coculture, active RA sera treatment of osteoblasts stimulated while addition of OPG or IL-6 inhibitory antibodies significantly reduced the number of osteoclasts. CONCLUSION: Active RA sera contain circulating factors, likely cytokines and chemokines, that might contribute to bone loss by directly inhibiting osteoblast proliferation and differentiation, but especially, these factors modulate endogenous cytokine production by osteoblasts, thereby affecting osteoclastogenesis.


Assuntos
Artrite Reumatoide/imunologia , Citocinas/biossíntese , Mediadores da Inflamação/imunologia , Osteoblastos/imunologia , Osteoclastos/fisiologia , Adulto , Idoso , Fosfatase Alcalina/metabolismo , Artrite Reumatoide/patologia , Diferenciação Celular/imunologia , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Pessoa de Meia-Idade , Osteoblastos/patologia , Ligante RANK/imunologia , Indução de Remissão
12.
Clin Pharmacol Ther ; 96(4): 482-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24960519

RESUMO

We describe here the design and initial implementation of the eMERGE-PGx project. eMERGE-PGx, a partnership of the Electronic Medical Records and Genomics Network and the Pharmacogenomics Research Network, has three objectives: (i) to deploy PGRNseq, a next-generation sequencing platform assessing sequence variation in 84 proposed pharmacogenes, in nearly 9,000 patients likely to be prescribed drugs of interest in a 1- to 3-year time frame across several clinical sites; (ii) to integrate well-established clinically validated pharmacogenetic genotypes into the electronic health record with associated clinical decision support and to assess process and clinical outcomes of implementation; and (iii) to develop a repository of pharmacogenetic variants of unknown significance linked to a repository of electronic health record-based clinical phenotype data for ongoing pharmacogenomics discovery. We describe site-specific project implementation and anticipated products, including genetic variant and phenotype data repositories, novel variant association studies, clinical decision support modules, clinical and process outcomes, approaches to managing incidental findings, and patient and clinician education methods.


Assuntos
Bases de Dados Genéticas , Registros Eletrônicos de Saúde/organização & administração , Variação Genética , Adolescente , Idoso , Criança , Tratamento Farmacológico , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Bases de Conhecimento , Masculino , Pessoa de Meia-Idade , Farmacogenética , Fenótipo , Projetos Piloto , Análise de Sequência de DNA , Adulto Jovem
13.
Clin Genet ; 86(1): 50-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24588254

RESUMO

We provide a mini-review of how biobanks can support clinical genetics in the era of personalized medicine. We discuss types of biobanks, including disease specific and general biobanks not focused on one disease. We present considerations in setting up a biobank, including consenting and governance, biospecimens, risk factor and related data, informatics, and linkage to electronic health records for phenotyping. We also discuss the uses of biobanks and ongoing considerations, including genotype-driven recruitment, investigations of gene-environment associations, and the re-use of data generated from studies. Finally, we present a brief discussion of some of the unresolved issues, such as return of research results and sustaining biobanks over time. In summary, carefully designed biobanks can provide critical research and infrastructure support for clinical genetics in the era of personalized medicine.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Bancos de Espécimes Biológicos/tendências , Biologia Computacional/métodos , Bases de Dados Genéticas/tendências , Genética Médica/métodos , Medicina de Precisão/métodos , Genética Médica/tendências , Genótipo , Humanos , Medicina de Precisão/tendências
14.
Science ; 325(5936): 68-70, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19574386

RESUMO

The light detection and ranging instrument on the Phoenix mission observed water-ice clouds in the atmosphere of Mars that were similar to cirrus clouds on Earth. Fall streaks in the cloud structure traced the precipitation of ice crystals toward the ground. Measurements of atmospheric dust indicated that the planetary boundary layer (PBL) on Mars was well mixed, up to heights of around 4 kilometers, by the summer daytime turbulence and convection. The water-ice clouds were detected at the top of the PBL and near the ground each night in late summer after the air temperature started decreasing. The interpretation is that water vapor mixed upward by daytime turbulence and convection forms ice crystal clouds at night that precipitate back toward the surface.


Assuntos
Gelo , Marte , Vapor , Atmosfera , Meio Ambiente Extraterreno , Astronave , Temperatura , Fatores de Tempo
15.
Int J Food Sci Nutr ; 59(7-8): 671-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19382338

RESUMO

In addition to their use as food and spice, chillies have been popular in both Ayurvedic and homoeopathic treatments since ancient times. Elemental analyses on their seeds with the help of X-ray fluorescence spectra reveal the presence of hitherto undetected magnesium, along with sulphur and chlorine. Fourier transform infrared and Fourier transform Raman spectra of the seeds reveal the presence of specific functional groups, attributed to the different bands present in the spectra. Ascorbic acid, reported to be the vitamin present in maximum amount in chilli peppers, is conspicuous by its absence in the seeds.


Assuntos
Capsicum/química , Sementes/química , Análise Espectral , Oligoelementos/química
16.
Rev Sci Instrum ; 78(4): 045105, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17477691

RESUMO

A novel high-speed tensile test instrument is described, capable of measuring the mechanical response of elastomers at strain rates ranging from 10 to 1600 s(-1) for strains through failure. The device employs a drop weight that engages levers to stretch a sample on a horizontal track. To improve dynamic equilibrium, a common problem in high speed testing, equal and opposite loading was applied to each end of the sample. Demonstrative results are reported for two elastomers at strain rates to 588 s(-1) with maximum strains of 4.3. At the higher strain rates, there is a substantial inertial contribution to the measured force, an effect unaccounted for in prior works using the drop weight technique. The strain rates were essentially constant over most of the strain range and fill a three-decade gap in the data from existing methods.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(6 Pt 1): 061503, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15244572

RESUMO

A ubiquitous domain pattern is observed in two-phase viscoelastic fluids falling within the simple paradigm of soft viscoelastic domains suspended in a less viscoelastic fluid under shear flow. Three strikingly different complex fluids exhibit the same shear-induced domain structure, which we relate to the elasticity of the dispersed phase via an approximate Weissenberg number. We suggest a physical mechanism for the formation of this pervasive pattern, independent of the dynamic origin of the elasticity of the suspended phase.

18.
Phys Rev Lett ; 92(4): 048302, 2004 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-14995413

RESUMO

We report an elastic instability associated with flow-induced clustering in semidilute non-Brownian colloidal nanotubes. Rheo-optical measurements are compared with simulations of mechanical flocculation in sheared fiber suspensions, and the evolving structure is characterized as a function of confinement and shear stress. The transient rheology is correlated with the evolution of highly elastic vorticity-aligned aggregates, with the underlying instability being somewhat ubiquitous in complex fluids.

19.
Indian J Physiol Pharmacol ; 35(3): 199-202, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1791062

RESUMO

Renal functions decline with age. Only after considerable renal reserves are lost, the traditional clinical tests of urine, blood or clearance levels reveal the defect. The urine quantity & contents passed in 24 hrs both by young and elderly, show little differences between the two groups. Their creatinine clearances are also comparable. Earlier Studies on water dilution test had shown significant differences between the performance of the young and elderly subjects, indicating decrease in renal efficiency on ageing. In the present study 4 hourly collections of urine showed that the night collections in elderly subjects were comparatively larger in volume, electrolytes and other components as compared with younger subjects. The kidneys of the elderly seem to compensate by labouring at night, while the young have their restful phase. Thus in addition to water dilution test, comparison of day/night outputs of urine can be taken as an early indicator of renal deterioration in elderly.


Assuntos
Envelhecimento/fisiologia , Rim/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Creatinina/sangue , Creatinina/urina , Humanos , Rim/crescimento & desenvolvimento , Masculino , Pessoa de Meia-Idade , Ureia/sangue , Ureia/urina , Urina/química
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