Les difficultés d'intégration des immigrés turcs en RFA

Cet article entend faire le point sur l'immigration turque en Allemagne en s'intéressant à ses motifs pour étudier ensuite la situation de ceux qui sont rentrés en Turquie avant de pointer les difficultés d'intégration de ceux qui sont restés en Allemagne

Parametric Influences on Heat Affected Zone in Micro-channel Milling Process of Zirconia Ceramic

Zirconia, a bio-ceramic, is widely utilized in bioengineering, biomedical implants, dentistry, and the automotive industry due to high hardness, excellent wear resistance, etc. However, it is difficult to attain micro features on zirconia utilizing a laser machining system for the aforesaid properties. The paper deals with the study of the Heat Affected Zone (HAZ) formation during the micro-channel milling (V-shaped cross-sections) of zirconia utilizing a nanosecond fiber laser system. Experiments are accomplished to examine the consequence of control variables namely transverse feed, pulse frequency, laser power, scan number, and scan speed. The influence of each of the laser process variables on response parameter are studied in order to get the significant trends of laser parameters. With the increment of laser power, the number of pass and transverse feed, HAZ width dimensions tend to increase. The reverse phenomena are observed for pulse frequency and scan speed. The lower HAZ width which is achieved as 31.74 μm at a parametric setting of average power at 10 W, pulse frequency at 65 kHz, scanning speed at 11 mm/s, a number of pass at 1, transverse feed at 0.005 mm

Corneal properties in children with congenital isolated growth hormone deficiency

<b>AIM:</b>To compare the corneal parameters of children with congenital isolated growth hormone deficiency and healthy subjects.<b>METHODS:</b> In this cross-sectional, prospective study, 50 cases with growth hormone (GH) deficiency treated with recombinant GH and 71 healthy children underwent a complete ophthalmic examination. The corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated intraocular pressure (IOPcc) were measured with the Ocular Response Analyzer (ORA). Central corneal thickness (CCT) was measured by a ultrasonic pachymeter.<b>RESULTS:</b> The mean age was 13.0±3.0 years in the GH deficiency group consisting of 21 females and 29 males and 13.4±2.4 years in the healthy children group consisting of 41 females and 30 males. There was no statistically significant difference between the groups for gender or age (Chi-square test, <i>P</i>=0.09; independent <i>t</i>-test, <i>P</i>=0.28, respectively). The mean duration of recombinant GH therapy was 3.8±2.4y in the study group. The mean CH, CRF, IOPg and IOPcc values were 11.0±2.0, 10.9±1.9, 15.1±3.3, and 15.1±3.2 mm Hg respectively in the study group. The same values were 10.7±1.7, 10.5±1.7, 15.2±3.3, and 15.3±3.4 mm Hg respectively in the control group. The mean CCT values were 555.7±40.6, 545.1±32.5 µm in the study and control groups respectively. There was no statistically significant difference between the two groups for CH, CRF, IOPg, IOPcc measurements or CCT values (independent <i>t</i>-test, <i>P</i>=0.315, 0.286, 0.145, 0.747, 0.13 respectively).<b>CONCLUSION:</b> Our study suggests that GH deficiency does not have an effect on the corneal parameters and CCT values. This observation could be because of the duration between the beginning of disease and the diagnosis and beginning of GH therapy

Improvement of Anaerobic Digestion of Lignocellulosic Biomass by Hydrothermal Pretreatment

Lignocellulosic biomass, comprising of cellulose, hemicellulose, and lignin, is a difficultto- degrade substrate when subjected to anaerobic digestion. Hydrothermal pretreatment of lignocellulosic biomass could enhance the process performance by increasing the generation of methane, hydrogen, and bioethanol. The recalcitrants (furfurals, and 5-HMF) could be formed at high temperatures during hydrothermal pretreatment of lignocellulosic biomass, which may hinder the process performance. However, the detoxification process involving the use of genetically engineered microbes may be a promising option to reduce the toxic effects of inhibitors. The key challenge lies in the scaleup of the hydrothermal process, mainly due to necessity of upholding high temperature in sizeable reactors, which may demand high capital and operational costs. Thus, more efforts should be towards the techno-economic feasibility of hydrothermal pre-treatment at full scale

Comparison of autofluorescence and optical coherence tomography findings in acute and chronic central serous chorioretinopathy

AIM:To discuss and compare the fundus autofluorescence (FAF) and optical coherence tomography (OCT) in acute or chronic central serous chorioretinopathy (CSCR).METHODS: Medical records of 100 cases of CSCR were reviewed. Acute and chronic cases were evaluated according to the duration of decreased visual acuity, serous retinal detachment (RD) and focal leakage on fluorescein angiography (FA). Chi-square test was used for statistical analysis.RESULTS:Forty cases had acute and 60 cases had chronic CSCR. FAF showed focal hypo-autofluorescence in 34 (85%) and iso-autofluorescence in 6 (15%) of acute cases and hypo-autofluorescence in 51 (85%), hyper-autofluorescence in 6 (10%) and iso-autofluorescence in 3 (5%) of chronic cases. OCT showed serous RD with distinct borders correlated with FAF findings (hypo-autofluorescence) in all acute CSCR cases. In chronic CSCR group, OCT showed serous RD with indistinct borders correlated with FAF findings. The differences between the OCT and FAF findings of the two groups were significant (P=0.000).CONCLUSION: OCT and FAF findings can support the clinical observations in differential diagnosis of acute and chronic CSCR and help clinicians to evaluate retinal pigment epithelium, outer segments of photoreceptors and the components of serous RD

Traces of trauma – a multivariate pattern analysis of childhood trauma, brain structure and clinical phenotypes

Background: Childhood trauma (CT) is a major yet elusive psychiatric risk factor, whose multidimensional conceptualization and heterogeneous effects on brain morphology might demand advanced mathematical modeling. Therefore, we present an unsupervised machine learning approach to characterize the clinical and neuroanatomical complexity of CT in a larger, transdiagnostic context. Methods: We used a multicenter European cohort of 1076 female and male individuals (discovery: n = 649; replication: n = 427) comprising young, minimally medicated patients with clinical high-risk states for psychosis; patients with recent-onset depression or psychosis; and healthy volunteers. We employed multivariate sparse partial least squares analysis to detect parsimonious associations between combinations of items from the Childhood Trauma Questionnaire and gray matter volume and tested their generalizability via nested cross-validation as well as via external validation. We investigated the associations of these CT signatures with state (functioning, depressivity, quality of life), trait (personality), and sociodemographic levels. Results: We discovered signatures of age-dependent sexual abuse and sex-dependent physical and sexual abuse, as well as emotional trauma, which projected onto gray matter volume patterns in prefronto-cerebellar, limbic, and sensory networks. These signatures were associated with predominantly impaired clinical state- and trait-level phenotypes, while pointing toward an interaction between sexual abuse, age, urbanicity, and education. We validated the clinical profiles for all three CT signatures in the replication sample. Conclusions: Our results suggest distinct multilayered associations between partially age- and sex-dependent patterns of CT, distributed neuroanatomical networks, and clinical profiles. Hence, our study highlights how machine learning approaches can shape future, more fine-grained CT research

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Elastic-plastic thermal stresses in a composite disc with multiple holes

The goal of this study was to investigate elastic-plastic thermal stresses in a thermoplastic composite hollow disc with multiple holes. Different uniform temperature distributions were subjected to the disc as thermal loadings. The thermoplastic composite disc was reinforced by steel fibres as unidirectional for radial direction. Finite element method (FEM) was used to calculate both thermal and residual stresses. Therefore, the thermal stress analysis was carried out using ANSYS finite element software which is known a general purpose engineering simulation. Due to the composite disc having, different thermal expansions in radial and tangential directions, thermal stresses were created in it by the applied thermal loadings. The magnitude of the tangential stress components both elastic and elastic-plastic solutions was higher than the radial stress components except edges of multiple holes. In addition, the residual stress components were computed using elastic and elastic-plastic solution results. The calculated results pointed out that the magnitude of thermal and residual stresses were considerably affected increasing of uniform temperature loadings

An investigation of thermal elasto-plastic stress analysis of laminated thermoplastic composites with a circular hole under uniform temperature loading

This investigation was performed to study the response of a thermal elasto-plastic stress analysis and residual stresses on symmetric cross ply [0/90](s) and angle-ply [30/-30](s), [45/-45](s), [60/-60](s) steel fiber reinforced thermoplastic laminated plate, which is subjected to a uniform temperature load with a circular hole. To evaluate the effects of uniform temperature value and stacking sequence of the laminated thermoplastic composite plates on the thermal stress, the study was carried out using the finite element solution. For this purpose the solution was calculated by ANSYS analysis code. The width to diameter (L/D) ratio in the plate was selected as 10. The composite materials were assumed to be linearly hardening. The Tsai-Hill theory was used as a yield criterion. Thermoplastic laminated composite plates were simply supported. All thermal stress values depending on applied temperature are shown in tables. It was found that increasing uniform temperature values and stacking sequence of composite plates considerably affected thermal stresses