130 research outputs found
BMD-based assessment of local porosity in human femoral cortical bone
Cortical pores are determinants of the elastic properties and of the ultimate strength of bone tissue. An increase of the overall cortical porosity (Ct.Po) as well as the local coalescence of large pores cause an impairment of the mechanical competence of bone Therefore, Ct Po represents a relevant target for identifying patients with high fracture risk. However, given their small size, the in vivo imaging of cortical pores remains challenging. The advent of modern high-resolution peripheral quantitative computed tomography (HR-pQCT) triggered new methods for the clinical assessment of Ct Po at the peripheral skeleton, either by pore segmentation or by exploiting local bone mineral density (BMD) In this work, we compared BMD-based Ct.Po estimates with highresolution reference values measured by scanning acoustic microscopy. A calibration rule to estimate local Ct.Po from BMD as assessed by HR-pQCT was derived experimentally. Within areas of interest smaller than 0.5 mm(2), our model was able to estimate the local Ct.Po with an error of 3.4%. The incorporation of the BMD mhomogeneity and of one parameter from the BMD distribution of the entire scan volume led to a relative reduction of the estimate error of 30%, if compared to an estimate based on the average BMD. When applied to the assessment of Ct.Po within entire cortical bone cross-sections, the proposed BMD-based method had better accuracy than measurements performed with a conventional threshold-based approach.</p
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Access to RNA-sequencing data from 1,173 plant species: The 1000 Plant transcriptomes initiative (1KP)
The 1000 Plant transcriptomes initiative (1KP) explored genetic diversity by sequencing RNA from 1,342 samples representing 1,173 species of green plants (Viridiplantae).This data release accompanies the initiative's final/capstone publication on a set of 3 analyses inferring species trees, whole genome duplications, and gene family expansions. These and previous analyses are based on de novo transcriptome assemblies and related gene predictions. Here, we assess their data and assembly qualities and explain how we detected potential contaminations.These data will be useful to plant and/or evolutionary scientists with interests in particular gene families, either across the green plant tree of life or in more focused lineages
Correction: Large cortical bone pores in the tibia are associated with proximal femur strength
[This corrects the article DOI: 10.1371/journal.pone.0215405.
Temperatura de color correlacionada de la luz natural: análisis dinámico en espacios interiores
The response of the upper ocean to solar heating. I: The mixed layer
The results of two earlier papers on convection in the mixed layer and on the solar heating profile are here introduced into a one-dimensional model in order to investigate the following consequences of the daily cycle of solar heating in the upper ocean:
1. the daytime convection depth becomes less than the turbocline depth;
2. the convective power supply to turbulence in the mixed layer is reduced;
3. the mixed layer below the convection layer becomes stably stratified;
4. the depth of the turbocline is reduced, leaving a diurnal thermocline between it and the top of the seasonal thermocline;
5. the heat content and potential energy of the diurnal and seasonal thermoclines are increased, slowing down the subsequent nocturnal descent of the turbocline.
These diurnal changes are illustrated by integrating a one-dimensional model forced by the astronomical cycle of solar heating and seasonal variation of surface meteorology derived from Bunker's climatology. The model is integrated for 18 months to show the seasonal modulation of the diurnal cycle. Nocturnal convection plays a dominant role. The convection depth closely follows the thermal compensation depth during the day when they are less than the turbocline depth. Integrating the model with a 24-hour time step leads to large errors in the seasonal variation of mixed layer temperature and depth, and in the source term of isopycnic potential vorticity. The errors are reduced by using two time steps per day, one for the daytime when convection is quenched, the other for the night when it is active. A novel parametrization based on tuning the daily equivalent solar elevation to surface temperature further reduces the error. This parametrization is used to investigate the sensitivity of the seasonal cycles of mixed layer depth and temperature to: (1) seasonality in the surface fluxes; (2) systematic changes in the net annual solar heating; (3) random changes in the seasonal cycles of solar heating induced (i) monthly and (ii) daily. The sensitivity to uncertainty in seawater turbidity is investigated in the same way. The profile of isopycnic potential vorticity subducted into the thermocline depends on the vernal correlation of mixed layer depth and density, so gyre circulation is sensitive to solar heating in spring
Child and adolescent psychiatry patients coming of age: a retrospective longitudinal study of inpatient treatment in Tyrol
Problem Behavior in Children of Chronically Ill Parents: A Meta-Analysis
The aim of this meta-analysis is to examine whether children of chronically ill parents differ from norm groups in problem behavior. We report moderator effects and overall effect sizes for internalizing, externalizing and total problem behavior assessed by children and parents. In fixed effect models, we found a significant overall effect size for internalizing problem behavior (number of studies k = 19, total sample size N = 1,858, Cohen’s d = .23, p < .01) and externalizing problem behavior (k = 13, N = 1,525, d = .09, p < .01) but not for total problem behavior (k = 7; N = 896). Effects for internalizing and externalizing problem behavior were larger in non-cancer studies, in samples including younger children and younger ill parents, in samples defined by low average SES and in studies including parents with longer illness duration. In addition, effects for externalizing problem behavior were larger in studies characterized by a higher percentage of ill mothers and single parents. With exclusive self-report, effect sizes were significant for all problem behaviors. Based on these results, a family-centered approach in health care is recommended
Kinder körperlich kranker Eltern: Psychische Belastungen, Wege der Bewältigung und Perspektiven der seelischen Gesundheitsvorsorge
The Loss of Biodiversity as a Challenge for Sustainable Development: How Do Pupils in Chile and Germany Perceive Resource Dilemmas?
Associations between parental chronic pain and self-esteem, social competence, and family cohesion in adolescent girls and boys – family linkage data from the HUNT study
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