910 resultados para Voids related to solidification


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The reward systemin schizophrenia has been linked to the emergence of delusions on the one hand and to negative symptoms such as affective flattening on the other hand. Previous Diffusion Tensor Imaging (DTI) studies reported white matter microstructure alterations of regions related to the reward system. The present study aimed at extending these findings by specifically investigating connection pathways of the reward system in schizophrenia. Therefore, 24 patients with schizophrenia and 22 healthy controls matched for age and gender underwent DTI-scans. Using a probabilistic fiber tracking approachwe bilaterally extracted pathways connecting the ventral tegmental area (VTA) with the nucleus accumbens (NAcc), themedial and lateral orbitofrontal cortices (mOFC, lOFC), the dorsolateral prefrontal cortex (dlPFC) and the amygdala; as well as pathways connecting NAcc with mOFC, lOFC, dlPFC and amygdala resulting in a total of 18 connections. Probability indices forming part of a bundle of interest (PIBI) were compared between groups using independent t-tests. In 6 connection pathways PIBI-valueswere increased in schizophrenia. In 3 of these pathways the spatial extension of connection pathways was decreased. In schizophrenia patients, there was a negative correlation of PIBI-values and PANSS negative scores in the left VTA–amygdala and in the left NAcc–mOFC connection. A sum score of delusions and hallucinations correlated positively with PIBI-values of the left amygdala–NAcc connection. Structural organization of specific segments ofwhite matter pathways of the reward systemin schizophrenia may contribute to the emergence of delusions and negative symptoms in schizophrenia.

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We developed a novel delay discounting task to investigate outcome impulsivity in pigs. As impulsivity can affect aggression, and might also relate to proactive and reactive coping styles, eight proactive (HR) and eight reactive (LR) pigs identified in a manual restraint test ("Backtest", after Bolhuis et al., 2003) were weaned and mixed in four pens of four unfamiliar pigs, so that each pen had two HR and two LR pigs, and aggression was scored in the 9h after mixing. In the delay discounting task, each pig chose between two levers, one always delivering a small immediate reward, the other a large delayed reward with daily increasing delays, impulsive individuals being the ones discounting the value of the large reward quicker. Two novel strategies emerged: some pigs gradually switched their preference towards the small reward ('Switchers') as predicted, but others persistently preferred the large reward until they stopped making choices ('Omitters'). Outcome impulsivity itself was unrelated to these strategies, to urinary serotonin metabolite (5-HIAA) or dopamine metabolite (HVA) levels, aggression at weaning, or coping style. However, HVA was relatively higher in Omitters than Switchers, and positively correlated with behavioural measures of indecisiveness and frustration during choosing. The delay discounting task thus revealed two response strategies that seemed to be related to the activity of the dopamine system and might indicate a difference in execution, rather than outcome, impulsivity.

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Human trafficking is a complex and multifaceted problem that takes the form of economic, physical and sexual exploitation of people, both adults and children, who are reduced to simple products for commerce. Human trafficking in the United States also has both a domestic and an international aspect. Health care providers are in a unique position to screen for victims of trafficking and may provide important medical and psychological care for victims while in captivity and thereafter. Trafficked persons are likely to suffer a wide spectrum of health risks that reflect the unique circumstances and experiences in a trafficked victim’s life. Although trafficked victims typically have experienced inadequate medical care, once contact is made by the victim with the health care professionals, the opportunity then exists to identify, treat, and assist such victims. The range of services and supports required to appropriately respond to human trafficking victims once identified is broad and typically goes beyond just what is immediately provided by the health care professional and includes safe housing, legal advice, income support, and, for international victims, immigration status related issues. An informed and responsive community is necessary to serve both the international and domestic victims of human trafficking, and needs assessments demonstrated a number of barriers that hindered the delivery of effective services to human trafficking victims. One of the consistent needs identified to combat these barriers was enhanced training among all professionals who might come in contact with human trafficking victims. We highlight the efforts of the Houston Rescue and Restore Coalition (HRRC), a local grassroots non-profit organization whose mission focuses on raising awareness of human trafficking in the Greater Houston Metropolitan area. HRRC responded to the consistent recommendation from various community needs assessments for additional training of front line professionals who would have the opportunity to identify human trafficking victims and supported the design and pilot testing of a health professions training program around human trafficking. Dissemination of this type of training along with careful evaluation and continued refinement will be one way for health care professionals to engage in a positive manner with human trafficking victims.

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Hyalotekite, a framework silicate of composition (Ba,Pb,K)(4)(Ca,Y)(2)Si-8(B,Be)(2) (Si,B)(2)O28F, is found in relatively high-temperature(greater than or equal to 500 degrees C) Mn skarns at Langban, Sweden, and peralkaline pegmatites at Dara-i-Pioz, Tajikistan. A new paragenesis at Dara-i-Pioz is pegmatite consisting of the Ba borosilicates leucosphenite and tienshanite, as well as caesium kupletskite, aegirine, pyrochlore, microcline and quartz. Hyalotekite has been partially replaced by barylite and danburite. This hyalotekite contains 1.29-1.78 wt.% Y2O3, equivalent to 0.172-0.238 Y pfu or 8-11% Y on the Ca site; its Pb/(Pb+Ba) ratio ranges 0.36-0.44. Electron microprobe F contents of Langban and Dara-i-Pioz hyalotekite range 1.04-1.45 wt.%, consistent with full occupancy of the F site. A new refinement of the structure factor data used in the original structural determination of a Langban hyalotekite resulted in a structural formula, (Pb1.96Ba1.86K0.18)Ca-2(B1.76Be0.24)(Si1.56B0.44)Si8O28F, consistent with chemical data and all cations with positive-definite thermal parameters, although with a slight excess of positive charge (+57.14 as opposed to the ideal +57.00). An unusual feature of the hyalotekite framework is that 4 of 28 oxygens are non-bridging; by merging these 4 oxygens into two, the framework topology of scapolite is obtained. The triclinic symmetry of hyalotekite observed at room temperature is obtained from a hypothetical tetragonal parent structure via a sequence of displacive phase transitions. Some of these transitions are associated with cation ordering, either Pb-Ba ordering in the large cation sites, or B-Be and Si-B ordering on tetrahedral sites. Others are largely displacive but affect the coordination of the large cations (Pb, Ba, K, Ca). High-resolution electron microscopy suggests that the undulatory extinction characteristic of hyalotekite is due to a fine mosaic microstructure. This suggests that at least one of these transitions occurs in nature during cooling, and that it is first order with a large volume change. A diffuse superstructure observed by electron diffraction implies the existence of a further stage of short-range cation ordering which probably involves both (Pb,K)-Ba and (BeSi,BB)-BSi.

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Preclinical studies using animal models have shown that grey matter plasticity in both perilesional and distant neural networks contributes to behavioural recovery of sensorimotor functions after ischaemic cortical stroke. Whether such morphological changes can be detected after human cortical stroke is not yet known, but this would be essential to better understand post-stroke brain architecture and its impact on recovery. Using serial behavioural and high-resolution magnetic resonance imaging (MRI) measurements, we tracked recovery of dexterous hand function in 28 patients with ischaemic stroke involving the primary sensorimotor cortices. We were able to classify three recovery subgroups (fast, slow, and poor) using response feature analysis of individual recovery curves. To detect areas with significant longitudinal grey matter volume (GMV) change, we performed tensor-based morphometry of MRI data acquired in the subacute phase, i.e. after the stage compromised by acute oedema and inflammation. We found significant GMV expansion in the perilesional premotor cortex, ipsilesional mediodorsal thalamus, and caudate nucleus, and GMV contraction in the contralesional cerebellum. According to an interaction model, patients with fast recovery had more perilesional than subcortical expansion, whereas the contrary was true for patients with impaired recovery. Also, there were significant voxel-wise correlations between motor performance and ipsilesional GMV contraction in the posterior parietal lobes and expansion in dorsolateral prefrontal cortex. In sum, perilesional GMV expansion is associated with successful recovery after cortical stroke, possibly reflecting the restructuring of local cortical networks. Distant changes within the prefrontal-striato-thalamic network are related to impaired recovery, probably indicating higher demands on cognitive control of motor behaviour.

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The present study investigated the relationship between psychometric intelligence and temporal resolution power (TRP) as simultaneously assessed by auditory and visual psychophysical timing tasks. In addition, three different theoretical models of the functional relationship between TRP and psychometric intelligence as assessed by means of the Adaptive Matrices Test (AMT) were developed. To test the validity of these models, structural equation modeling was applied. Empirical data supported a hierarchical model that assumed auditory and visual modality-specific temporal processing at a first level and amodal temporal processing at a second level. This second-order latent variable was substantially correlated with psychometric intelligence. Therefore, the relationship between psychometric intelligence and psychophysical timing performance can be explained best by a hierarchical model of temporal information processing.

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Abstract Within the field of neuroscientific research on second language learning, considerable attention has been devoted to functional and recently also structural changes related to second language acquisition. The present literature review summarizes studies that investigated structural changes related to bilingualism. Furthermore, as recent evidence has suggested that native-like exposure to a second language (i.e., a naturalistic learning setting or immersion) considerably impacts second language learning, all findings are reflected with respect to the learning environment. Aggregating the existing evidence, we conclude that structural changes in left inferior frontal and inferior parietal regions have been observed in studies on cortical gray matter changes, while the anterior parts of the corpus callosum have been repeatedly found to reflect bilingualism in studies on white matter (WM) connectivity. Regarding the learning environment, no cortical alterations can be attributed specifically to naturalistic or classroom learning. With regard to WM changes, one might tentatively propose that changes in IFOF and SLF are possibly more prominently observed in studies investigating bilinguals with a naturalistic learning experience. However, future studies are needed to replicate and strengthen the existing evidence and to directly test the impact of naturalistic exposure on structural brain plasticity.

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OBJECTIVES Retrospectively, we assessed the likelihood that peri-implantitis was associated with a history of systemic disease, periodontitis, and smoking habits. METHODS Data on probing pocket depth (PPD), bleeding on probing (BOP), and radiographic bone levels were obtained from individuals with dental implants. Peri-implantitis was defined as described by Sanz & Chapple 2012. Control individuals had healthy conditions or peri-implant mucositis. Information on past history of periodontitis, systemic diseases, and on smoking habits was obtained. RESULTS One hundred and seventy-two individuals had peri-implantitis (mean age: 68.2 years, SD ± 8.7), and 98 individuals (mean age: 44.7 years, SD ± 15.9) had implant health/peri-implant mucositis. The mean difference in bone level at implants between groups was 3.5 mm (SE mean ± 0.4, 95% CI: 2.8, 4.3, P < 0.001). A history of cardiovascular disease was found in 27.3% of individuals with peri-implantitis and in 3.0% of individuals in the implant health/peri-implant mucositis group. When adjusting for age, smoking, and gender, odds ratio (OR) of having peri-implantitis and a history of cardiovascular disease was 8.7 (95% CI: 1.9, 40.3 P < 0.006), and odds ratio of having a history of periodontitis was 4.5 (95% CI 2.1, 9.7, P < 0.001). Smoking or gender did not significantly contribute to the outcome. CONCLUSIONS In relation to a diagnosis of peri-implantitis, a high likelihood of comorbidity was expressed by a history of periodontitis and a history of cardiovascular disease.

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OBJECTIVE To assess patients' outcomes after subacromial or glenohumeral injections based on the degree of lateral extension of the acromion. METHODS 307 patients were prospectively included after therapeutic fluoroscopy-guided subacromial (n = 148) or glenohumeral (n = 159) injections with anaesthetic and long-acting corticosteroids. Pre- and post-injection outcomes at 1 week and 1 month were obtained using the 11-point numerical rating scale (NRS) for pain. Lateral extension of the acromion was quantified and categorized by the critical shoulder angle (CSA) and the acromion index (AI) on anteroposterior conventional radiographs. RESULTS Patients' outcomes at 1 week and 1 month were significantly improved (p < 0.001) compared to baseline for subacromial and glenohumeral injection patients. Patients with a CSA <35° showed significantly higher pain reduction 1 month after subacromial injection compared to patients with a CSA >35° (4.2 ± 2.6 vs. 3.2 ± 3.0, p = 0.04). A significant difference in the 1-month NRS change in pain scores is noted for smaller AIs after subacromial injection (4.3 ± 2.8 vs. 2.6 ± 2.9; p = 0.01). No significant association was noted between clinical outcome and the lateral extension of the acromion after glenohumeral joint injections. CONCLUSIONS A short lateral extension of the acromion was associated with better clinical outcomes in subacromial injection patients but not in glenohumeral injection patients. KEY POINTS • Patients' outcomes at 1 month improved significantly compared to baseline for subacromial injections. • Patients' outcomes at 1 month improved significantly compared to baseline for glenohumeral injections. • Short acromial lateralization was associated with better clinical outcome after subacromial injection. • The acromial lateralization was not associated with clinical outcome after glenohumeral injection.

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Objective: A number of intrinsic and extrinsic risk factors for the rupture of intracranial aneurysms have been identified. Still, the cause precipitating aneurysm rupture remains unknown in many cases. In addition, it has been observed that aneurysm ruptures are clustered in time but the trigger mechanism remains obscure. As solar activity has been associated with cardiovascular mortality and morbidity we decided to study ist association to aneurysm rupture in the Swiss population. Method: Patient data was extracted from the Swiss SOS database, at time of analysis covering 918 patients with angiography-proven aSAH treated at seven Swiss neurovascular centers between 01/01/2009 – 12/31/2011. The number of aneurysm rupture per day, week, month (Daily/Weekly/Monthly Rupture Frequency = RF) was measured and correlated to the absolute amount and the change in various parameters of interest representing continuous measurements of solar activity (radioflux (F10.7 index), solar proton flux, solar flare occurrence, planetary K-index/planetary A-index) using Poisson regression analysis. Results: Of a consecutive series of 918 cases of SAH, precise determination of the date of symptom onset was possible in 816 (88.9%). During the period of interest there were 517 days without recorded aneurysm rupture. There were 398, 139, 27 and 12 days with 1, 2, 3, and 4 ruptures per day. Five or 6 ruptures were only noted on a single day each. Poisson regression analysis demonstrated a significant correlation of F10.7 index and aneurysm rupture (incidence rate ratio (IRR) = 1.006303; standard error (SE) 0.0013201; 95% confidence interval (CI) 1.003719 – 1.008894; p<0.001), according to which every 1-unit increase of the F10.7 index increased the count for an aneurysm to rupture by 0.63%. As the F10.7 index is known to correlate well with the Space Environment Services Center (SESC) sunspot number, we performed additional analyses on SESC sunspot number and sunspot area. Here, a likewise statistically significant relationship of both the SESC sunspot number (IRR 1.003413; SE 0.0007913; 95%CI 1.001864 – 1.004965; p<0.001) and the sunspot area (IRR 1.000419; SE 0.0000866; 95%CI 1.000249 – 1.000589; p<0.001) emerged. All other variables analyzed showed no correlation with RF. Conclusions: Using valid methods, we found higher radioflux, sunspot number and sunspot area to be associated with an increased count of aneurysm rupture. Since we were using rupture frequencies rather than incidences and because we cannot explain the physiological basis of this statistical association, the clinical meaningfulness of this statistical association must be interpreted carefully. Future studies are warranted to rule out a type-1 error.

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Human auditory nerve afferents consist of two separate systems; one is represented by the large type I cells innervating the inner hair cells and the other one by the small type II cells innervating the outer hair cells. Type I spiral ganglion neurons (SGNs) constitute 96% of the afferent nerve population and, in contrast to other mammals, their soma and pre- and post-somatic segments are unmyelinated. Type II nerve soma and fibers are unmyelinated. Histopathology and clinical experience imply that human SGNs can persist electrically excitable without dendrites, thus lacking connection to the organ of Corti. The biological background to this phenomenon remains elusive. We analyzed the pre- and post-somatic segments of the type I human SGNs using immunohistochemistry and transmission electron microscopy (TEM) in normal and pathological conditions. These segments were found surrounded by non-myelinated Schwann cells (NMSCs) showing strong intracellular expression of laminin-β2/collagen IV. These cells also bordered the perikaryal entry zone and disclosed surface rugosities outlined by a folded basement membrane (BM) expressing laminin-β2 and collagen IV. It is presumed that human large SGNs are demarcated by three cell categories: (a) myelinated Schwann cells, (b) NMSCs and (c) satellite glial cells (SGCs). Their BMs express laminin-β2/collagen IV and reaches the BM of the sensory epithelium at the habenula perforata. We speculate that the NMSCs protect SGNs from further degeneration following dendrite loss. It may give further explanation why SGNs can persist as electrically excitable monopolar cells even after long-time deafness, a blessing for the deaf treated with cochlear implantation.

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In dairy cows, milk yield increases rapidly after parturition until a peak at around wk 6 of lactation. However, the description of the shape of the lactation curve is commonly based on weekly average milk yields. For a more detailed analysis of the milk production curve from the very beginning of lactation including the colostral period and the effect of colostrum yield on further lactational performance, the first 10 milkings after parturition, daily milk yields from d 1 to 28 of lactation, and the cumulative milk production on d 100 to 305 of lactation were investigated in 17 primiparous and 39 multiparous cows milked twice daily. Milk yield at the first milking after parturition (colostrum) ranged from 1.3 to 20.7kg (Δ=19.4kg) in multiparous and from 1.8 to 10.9kg in primiparous animals (Δ=9.1kg). At the tenth milking, milk production ranged from 9.2 to 21.5kg (Δ=12.3kg) in multiparous and from 7.0 to 15.2kg (Δ=8.2kg) in primiparous animals. Immediately after parturition, daily milk production increased rapidly, but after approximately 1wk in lactation, the slope of the daily milk production curve flattened and continued more linear. A nonlinear regression equation was used to determine this timely change, which occurred earlier in primiparous (d 6.9±0.3) than in multiparous cows (d 8.2±0.2). The correlation between the amount of first colostrum and milk production during further lactation decreased already from 0.47 on d 5 to 0.32 on d 14. In multiparous cows, the correlation between total milk production of the previous 305d standard lactation and the amount of first colostrum was not significant (correlation=0.29), whereas the correlation with the daily production increased from 0.45 on d 5 to 0.69 on d 14. However, in primiparous animals, correlations between first-colostrum yield and daily milk yields up to d 28 of lactation were not significant, possibly due to the smaller sample size compared with multiparous animals. First-colostrum yield and cumulative milk production of 100, 200, and 305 lactation days were not significantly correlated in multiparous and primiparous cows. In conclusion, the milk production during the first few milkings is widely independent from the overall production level of a cow. Potentially, genetic selection toward lower milk yield during the very first days after parturition at a simultaneously high lactational performance may be a tool to ensure sufficient colostrum quality and to reduce the metabolic load around parturition.

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A common training plan in general internal medicine was a brave enterprise started in 2011 in accordance with the common objectives of the Swiss Society of General Medicine and the Swiss Society of Internal Medicine. The next challenge will be the dissolution of the two Societies and therefore the creation of an unique new association in 2015. This is an extraordinary opportunity to bring together the specific qualities of each association and to create a new society. Issues, objectives and secondary benefits expected from the creation of the largest national society of a medical discipline are explored as a joint discussion in this article.