1,271 research outputs found
Nonlinear dielectric effect of dipolar fluids
The nonlinear dielectric effect for dipolar fluids is studied within the
framework of the mean spherical approximation (MSA) of hard core dipolar Yukawa
fluids. Based on earlier results for the electric field dependence of the
polarization our analytical results show so-called normal saturation effects
which are in good agreement with corresponding NVT ensemble Monte Carlo
simulation data. The linear and the nonlinear dielectric permittivities
obtained from MC simulations are determined from the fluctuations of the total
dipole moment of the system in the absence of an applied electric field. We
compare the MSA based theoretical results with the corresponding Langevin and
Debye-Weiss behaviors.Comment: 10 pages including 4 figure
Oxidation and Structuring of Polydicyclopentadiene Thin Layers
It has been shown that polymeric film coatings derived from polydicyclopentadiene are subject to oxidation and structuring in air. Oxidation in air of double bonds in films gradually happens during several weeks and it comes amid an increase of adsorption band of carbonyl and hydroxyl groups in polymers infrared spectrums. Moreover, because of selective oxidation of cis-configured chains, structuring occurs around the double bonds in the polymer chain in polydicyclopentadiene films acquired by metathesis polymerization
Experience with a Comprehensive Multidisciplinary Geriatric Oncology Center
Research Goals 1. Describe the population seen in the SAOC over the past 6 years Remediate and complete the EPIC flowsheets Merge data with existing RedCAP dat
Estrogen inhibits GH signaling by suppressing GH-induced JAK2 phosphorylation, an effect mediated by SOCS-2
Oral estrogen administration attenuates the metabolic action of growth hormone (GH) in humans. To investigate the mechanism involved, we studied the effects of estrogen on GH signaling through Janus kinase (JAK)2 and the signal transducers and activators of transcription (STATs) in HEK293 cells stably expressing the GH receptor (293GHR), HuH7 (hepatoma) and T-47D (breast cancer) cells. 293GHR cells were transiently transfected with an estrogen receptor-ι expression plasmid and luciferase reporters with binding elements for STAT3 and STAT5 or the β-casein promoter. GH stimulated the reporter activities by four- to sixfold. Cotreatment with 17β-estradiol (E2) resulted in a dose-dependent reduction in the response of all three reporters to GH to a maximum of 49-66% of control at 100 nM (P < 0.05). No reduction was seen when E2 was added 1-2 h after GH treatment. Similar inhibitory effects were observed in HuH7 and T-47D cells. E2 suppressed GH-induced JAK2 phosphorylation, an effect attenuated by actinomycin D, suggesting a requirement for gene expression. Next, we investigated the role of the suppressors of cytokine signaling (SOCS) in E2 inhibition. E2 increased the mRNA abundance of SOCS-2 but not SOCS-1 and SOCS-3 in HEK293 cells. The inhibitory effect of E2 was absent in cells lacking SOCS-2 but not in those lacking SOCS-1 and SOCS-3. In conclusion, estrogen inhibits GH signaling, an action mediated by SOCS-2. This paper provides evidence for regulatory interaction between a sex steroid and the GH/JAK/STAT pathway, in which SOCS-2 plays a central mechanistic role
Applicability of the telephone interview for cognitive status (modified) in a community sample with low education level: association with an extensive neuropsychological battery
Objective
To explore the applicability of a Portuguese (PT) version of the Telephone Interview for Cognitive Status (TICS), with a delayed recall item [modified (M)], here termed TICSM-PT, against an extensive (in-person) battery of neuropsychological instruments, in a sample of older individuals with low educational level and without clinically manifest/diagnosed cognitive impairment.
Methods
Following translation/back-translation and pilot testing in 33 community dwellers, 142 community dwellers aged 52 to 84years (mean=67.45, SD=7.91) were selected from local health care centres for the study (convenience sampling; stratified age and gender). Cronbach's alpha was used to assess internal consistency, and convergent validity was evaluated through the correlation between TICSM-PT and the Mini Mental State Examination (MMSE), as well as with a comprehensive battery of cognitive instruments. Divergent/discriminant validity was assessed through a battery of psychological instruments. The receiver operating curve was determined for TICSM-PT to classify participants with and without possible indication of cognitive impairment.
Results
TICSM-PT showed a satisfactory internal consistency (Cronbach's alpha=0.705), convergent validity and discriminant validity. TICSM-PT presented a positive association with the global cognitive measures Mini Mental State Examination and the Montreal Cognitive Assessment, and also with most neuropsychological parameters. Receiver operating curve curves presented a sensitivity of 90.6% and specificity of 73.7%. The area under the curve statistic yielded a threshold score equal or below 13.5 for cognitive impairment.
Conclusion
TICSM-PT is a practical tool for rapid cognitive assessment among older individuals with low educational background.European Commission (FP7): âSwitchBoxâ (contract HEALTH-F2-2010-259772) and co-financed by the Portuguese North Regional Operational Program (ON.2 â O Novo Norte) under the National Strategic Reference Framework (QREN), through the European Regional Development Fund (FEDER). TCC is a recipient of a doctoral fellowship from the Portuguese Foundation for Science and Technology (FCT; SFRH/BD/90078/2012), CPN, PSM and LA of research fellowships from the âMyHealthâ project (DoITâDesenvolvimento e Operacionalização da Investigação de Translação, contract DoIT-13853) and NCS of a âSwitchboxâ projec
A video-based educational intervention for providers regarding colorectal cancer screening
Methods:
Email sent to providers asking them to complete a 7 question survey regarding knowledge and self-reported comfort in screening for colorectal cancer using a shared decision-making approach.https://jdc.jefferson.edu/patientsafetyposters/1045/thumbnail.jp
Nucleon to Delta Weak Excitation Amplitudes in the Non-relativistic Quark Model
We investigate the nucleon to Delta(1232) vector and axial vector amplitudes
in the non-relativistic quark model of the Isgur-Karl variety. A particular
interest is to investigate the SU(6) symmetry breaking, due to color hyperfine
interaction. We compare the theoretical estimates to recent experimental
investigation of the Adler amplitudes by neutrino scattering.Comment: \documentstyle[aps]{revtex}, 21pages; 11 postscript figures. Accepted
for publication by Phys. Rev.
Phanerozoic variation in dolomite abundance linked to oceanic anoxia
The abundance of dolomitic strata in the geological record contrasts with the general rarity of locations where dolomite forms today, a discrepancy that has long posed a problem for their interpretation. Recent culture experiments show that dolomite can precipitate at room temperature, raising the possibility that many ancient dolomites may be of syngenetic origin. We compiled a large geodata set of secular variations in dolomite abundance in the Phanerozoic, coupled with compilations of genus richness of marine benthic invertebrates and sulfur-isotope variations in marine carbonates. These data show that dolomite abundance is negatively correlated to genus diversity, with four dolomite peaks occurring during mass extinctions. Dolomite peaks also correspond to the rapid increase in sulfur-isotope composition (δ³â´S), an indicator of enhanced sulfate reduction, in anoxic oceans. These results confirm that variations in dolomite abundance during the Phanerozoic were closely linked with changes in marine benthic diversity, with both in turn related to oceanic redox conditions
Alterations in the insulin-like growth factor system during treatment with diethylstilboestrol in patients with metastatic breast cancer
Alterations in the insulin-like growth factor (IGF)-system were evaluated in 16 patients treated with diethylstilboestrol 5âmg 3 times daily. Fasting blood samples were obtained before treatment and after 2 weeks, 1 month and/or 2â3 months on therapy. Insulin-like growth factor (IGF)-I, IGF-II, free IGF-I, IGF-binding protein (IGFBP)-1, IGFBP-2 and IGFBP-3 were measured by radioimmuno-/immunoradiometric-assays. All samples were subjected to Western ligand blotting as well as immunoblotting for IGFBP-3. We observed a significant decrease (percentage of pretreatment levels with 95 confidence intervals of the mean) in IGF-I [2 weeks 63% (49â79); 1 month 56% (44â73); 2â3 months 66% (53â82)], IGF-II [2 weeks 67% (56â80); 1 month 60% (52â68); 2â3 months 64% (55â75)], free IGF-I [2 weeks 29% (19â42); 1 month 25% (18â36); 2â3 months 31% (21â46)], IGFBP-2 [2 weeks 53% (18â156); 1 month 69% (61â78); 2â3 months 66% (57â78)], IGFBP-3 [2 weeks 74% (63â85); 1 month 69% (62â76); 2â3 months 71% (63â80)], as well as IGFBP-3 protease activity [2 weeks 71% (54â95); 1 month 78% (64â94); 2â3 months 71% (54â93)]. Contrary, the plasma levels (percentage of pretreatment levels with 95 confidence intervals of the mean) of IGFBP-1 [2 weeks 250% (127â495); 1 month 173% (138â542); 2â3 months 273% (146â510)] and IGFBP-4 [2 weeks 146% (112â192); 1 month 140% (116â169); 2â3 months 150% (114â198)] increased significantly. While this study confirms previous observations during treatment with oral oestrogens in substitution doses, the reduction in plasma IGF-II, free IGF-I, IGFBP-2 and -3 are all novel findings. A profound decrease in free IGF-I suggests a reduced bioavailability of IGFs from plasma to the tissues. These observations may be of significance to understand the mechanisms of the antitumour effect of diethylstilboestrol in pharmacological doses. Š 2001 Cancer Research Campaign http://www.bjcancer.co
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