547 research outputs found
TO EVALUATE THE EFFECT OF SURFACE MOISTURE ON DENTINAL SHEAR BOND STRENGTH OF GLASS IONOMER RESTORATIONS IN PRIMARY TEETH:AN IN -VITRO STUDY
Glass ionomer cements that form aninevitable part of pediatric restorative dentistryare inherently sensitive to moisture. The influenceof different drying techniques on the shear bondstrength of glass ionomer cements to primaryteeth dentin has not been established.Thepurpose of the study was to evaluate the effects ofdifferent drying methods for different drying timeperiods on the shear bond strength of GC Fuji IX toprimary tooth dentine
The role of sign in students' modeling of scalar equations
We describe students revising the mathematical form of physics equations to
match the physical situation they are describing, even though their revision
violates physical laws. In an unfamiliar air resistance problem, a majority of
students in a sophomore level mechanics class at some point wrote Newton's
Second Law as F = -ma; they were using this form to ensure that the sign of the
force pointed in a direction consistent with the chosen coordinate system while
assuming that some variables have only positive value. We use one student's
detailed explanation to suggest that students' issues with variables are
context-dependent, and that much of their reasoning is useful for productive
instruction.Comment: 5 pages, 1 figure, to be published in The Physics Teache
Brown adipose tissue in the buccal fat pad during infancy.
BackgroundThe buccal fat pad (BFP) is an encapsulated mass of adipose tissue thought to enhance the sucking capabilities of the masticatory muscles during infancy. To date, no conclusive evidence has been provided as to the composition of the BFP in early postnatal life.ObjectiveThe purpose of this study was to examine whether the BFP of neonates and infants is primarily composed of white adipose tissue (WAT) or brown adipose tissue (BAT).Materials and methodsThe percentage of fat in the BFP in 32 full-term infants (16 boys and 16 girls), aged one day to 10.6 months, was measured using magnetic resonance imaging (MRI) determinations of fat fraction.ResultsBFP fat fraction increased with age (r = 0.67; P<.0001) and neonates had significantly lower values when compared to older infants; 72.6 ± 9.6 vs. 91.8 ± 2.4, P<.0001. Multiple regression analysis indicated that the age-dependent relationship persisted after accounting for gender, gestational age, and weight percentile (P = .001). Two subjects (aged one and six days) depicted a change in the MRI characteristics of the BFP from primarily BAT to WAT at follow-up examinations two to six weeks later, respectively. Histological post-mortem studies of a 3 day and 1.1 month old revealed predominantly BAT and WAT in the BFP, respectively.ConclusionThe BFP is primarily composed of BAT during the first weeks of life, but of WAT thereafter. Studies are needed to investigate the contributions of BAT in the BFP to infant feeding and how it is altered by postnatal nutrition
Pregnancy and heart disease: risk and predictors of obstetric complications
Background: Although the disease is limited to only 0.5 to 1.0 percent of pregnant women, it remains an important cause of maternal morbidity and even mortality and has a significant effect on fetal outcome. Pregnancy and the peripartum period are associated with important cardiocirculatory changes that can lead to marked clinical deterioration in the woman with heart disease. Objectives of present study were to comprehend the impact of heart disease during pregnancy, to study the maternal and neonatal outcomes of pregnancies in women with heart disease, to identify predictors of pregnancy related complications in women with heart disease and to refine the risk stratification and to assess the individual risk of each pregnant woman with heart disease.Methods: It is a perspective study carried out at College Department of Obstetrics and Gynaecology, Govt. Medical, Kottayam from January 2012 to March 2014.Results: The outcomes of the pregnancies in 100 women who presented with heart disease and received their obstetrical care were evaluated. A maternal cardiac event, neonatal event, or both occurred in 37 completed pregnancies. A cardiac event complicated 8 completed pregnancies. It includes 2 maternal deaths, one on 9th postnatal day in women with hypertrophic obstructive cardiomyopathy and another in women with rheumatoid mitral stenosis who died of congestive cardiac failure. Most cardiac events (75%) occurred in the antepartum period and were either heart failure or cardiac arrhythmia.Conclusions: Strict prenatal care and early risk stratification during gestation are fundamental measures to improve the prognosis of pregnancy in women with heart disease
A computer graphics system for the building of macromolecular models into electron density maps
This is the published version, made available with the permission of the publisher.A brief description of the Molecular Modeling System-X graphics system hardware is followed by an explanation of the language which has been developed to realize an `electronic Richards box'. A variety of commands permits the construction and manipulation of a protein model within an electron density distribution. Usually about ten amino-acid residues can be displayed at any one time within a box of 20 grid points on an edge. The density is changed automatically as the viewer translates the model off the edge of the screen. He can then add, subtract or modify residues as appropriate
An Efficient Hardware Implementation of Detecting Targets from Remotely Sensed Hyperspectral Images
156-165Real-time implementation of hyperspectral imagery is an emerging research area which has notable remote sensing applications. It is challenging to process a huge volume of hyperspectral data under real-time constraints. Field programmable gate arrays are considered as an efficient hardware suited for onboard processing system. ATGP is a proven target detection algorithm which can automatically detect the target without any predefined data. In the traditional method, this algorithm involves orthogonal subspace projector which makes the hardware design too complex and slow. To speed up the process, Gram-Schmidt orthogonalization operator is used. Gram-Schmidt orthogonalization technique uses inner product instead of matrix inverse which makes the hardware design easy to implement in FPGA board. A detailed comparative analysis is carried out using three different hyperspectral images to emphasize the performance of the design which is adopted in this technique. The processing speed of the proposed ATGP-GS algorithm is 3.484 s for ROSIS Pavia University dataset, 1.781 s for HYDICE Urban dataset and 1.609 s for AVIRIS Cuprite dataset. The proposed algorithm is implemented in Virtex 6 ML605 evaluation board to evaluate the real-time performance of the system
Disrupted White Matter Microstructure Correlates With Impulsivity in Children and Adolescents With Bipolar Disorder
Altered white matter (WM) microstructure likely occurs in children with bipolar disorder (BD) with impulsivity representing one of the core features. However, altered WM microstructures and their age-related trendlines in children with BD and those at high-risk of developing BD, as well as correlations of WM microstructures with impulsivity, have been poorly investigated. In this study, diffusion MRI, cognitive, and impulsivity assessments were obtained from children/adolescents diagnosed with BD, offspring of individuals with BD (high-risk BD) and age-matched healthy controls. A novel atlas-based WM skeleton measurement approach was used to quantify WM microstructural integrity with all diffusion-tensor-imaging (DTI) metrics including fractional anisotropy, axial, mean and radial diffusivity to survey entire WM tracts and ameliorate partial volume effects. Among all DTI-derived metric measures, radial diffusivity quantifying WM myelination was found significantly higher primarily in corpus callosum and in the corona radiata in children with BD compared to controls. Distinguished from age-related progressively decreasing diffusivities and increasing fractional anisotropy in healthy controls, flattened age-related trendlines were found in BD group, and intermediate developmental rates were observed in high-risk group. Larger radial diffusivity in the corpus callosum and corona radiata significantly correlated with shorter response times to affective words that indicate higher impulsivity in the BD group, whereas no such correlation was found in the healthy control group. This work corroborates the progressive nature of pediatric BD and suggests that WM microstructural disruption involved in affective regulation and sensitive to impulsivity may serve as a biomarker of pediatric BD progression
Extensibility of External Magnetic Potential at High Latitudes - Antarctica
We investigated the external magnetic potential due to solar forcing, with nine years of data during 2001-2009, coveringthe deep solar minimum (2006-2009), at two stations: one is in the polar cap -Vostok (78º27'S, 106º52’E; mag. lat 83oS) andanother is in the subauroral region - Maitri (70º45'S, 11º43'E: mag. lat 67oS) in Antarctica. The significance of the work isassociated with space weather prediction and its impact on planet Earth. We used Advance Composition Explorer (ACE)satellite data for the aforesaid period for a thorough understanding of influences due to solar wind origin and to compare theparameter observed in these regions. We used the spherical cap harmonic analysis (SCHA) function as a tool. The inferenceindicates that at Vostok the magnitude is enhanced throughout and depicts a broad ambient external magnetic potential. Itseems to be essentially the intensification of the region 1 currents whereas at Maitri intense electric fields are producedduring geomagnetic perturbations which drive a system of disturbed time Region 2 currents over the quiet time currents.During this scenario in Maitri there are noticeable peaks or enhancements in the magnetic potential that can be observedmainly during geomagnetic disturbances. Hence the regression relation developed for external magnetic potentialcalculation, in terms of solar wind parameters agrees well with polar cap region and the area is relatively less exploredearlier, the present investigation can be expected to add knowledge about that regime
Embryonic stem cell-derived cardiomyocytes harbor a subpopulation of niche-forming Sca-1 + progenitor cells
Abstract The adult mammalian heart is known to contain a population of cardiac progenitor cells. It has not been unambiguously determined, however, whether these cells form as part of the developmental program of the heart or migrate there by way of the circulatory system. This study was done in order to determine the origin of this population of cells. A population of cardiomyocytes was established from mouse embryonic stem (ES) cells using a genetic selection technique. In order to determine whether cardiac progenitor cells exist within this ES cell-derived cardiomyocyte population, the cells were analyzed by fluorescence activated cell sorting (FACS) using an antibody directed against stem cell antigen-1 (Sca-1). We observed that approximately 4% of the cardiomyocyte population was composed of Sca-1 ? cells. When the Sca-1 ? cells were isolated by magnetic cell sorting and differentiated as cellular aggregates, contractions were observed in 100% of the aggregates. Gene expression studies using quantitative RT-PCR showed that these cells expressed terminally differentiated cardiac-specific genes. When three-dimensional cellular aggregates were formed from ES cell-derived cardiomyocytes co-cultured with adult HL-1 cardiomyocytes, the Sca-1 ? cells were found to ''sort out'' and form niches within the cell aggregates. Our data demonstrate that cardiac progenitor cells in the adult heart originate as part of the developmental program of the heart and that Sca-1 ? progenitor cells can provide an important in vitro model system to study the formation of cellular niches in the heart
Acute sleep restriction increases dietary intake in preschool‐age children
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/136000/1/jsr12450_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/136000/2/jsr12450.pd
- …