270 resultados para three gorges dam (TGD)


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The trabecular bone score (TBS) is an index of bone microarchitectural texture calculated from anteroposterior dual-energy X-ray absorptiometry (DXA) scans of the lumbar spine (LS) that predicts fracture risk, independent of bone mineral density (BMD). The aim of this study was to compare the effects of yearly intravenous zoledronate (ZOL) versus placebo (PLB) on LS BMD and TBS in postmenopausal women with osteoporosis. Changes in TBS were assessed in the subset of 107 patients recruited at the Department of Osteoporosis of the University Hospital of Berne, Switzerland, who were included in the HORIZON trial. All subjects received adequate calcium and vitamin D3. In these patients randomly assigned to either ZOL (n = 54) or PLB (n = 53) for 3 years, BMD was measured by DXA and TBS assessed by TBS iNsight (v1.9) at baseline and 6, 12, 24, and 36 months after treatment initiation. Baseline characteristics (mean ± SD) were similar between groups in terms of age, 76.8 ± 5.0 years; body mass index (BMI), 24.5 ± 3.6 kg/m(2) ; TBS, 1.178 ± 0.1 but for LS T-score (ZOL-2.9 ± 1.5 versus PLB-2.1 ± 1.5). Changes in LS BMD were significantly greater with ZOL than with PLB at all time points (p < 0.0001 for all), reaching +9.58% versus +1.38% at month 36. Change in TBS was significantly greater with ZOL than with PLB as of month 24, reaching +1.41 versus-0.49% at month 36; p = 0.031, respectively. LS BMD and TBS were weakly correlated (r = 0.20) and there were no correlations between changes in BMD and TBS from baseline at any visit. In postmenopausal women with osteoporosis, once-yearly intravenous ZOL therapy significantly increased LS BMD relative to PLB over 3 years and TBS as of 2 years. © 2013 American Society for Bone and Mineral Research.

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Nous présontons l'étalonnage d'un test mnésique de recognition dans un échantillon de 180 adultes francophones de la Suisse Romande. Le test comprend trois formes utilisant un matériel verbal (mots) ou non verbal (visages ou paysages). Une attention particulière est accordée à l'âge dans la présentation des résultats. Celui-ci affecte plus précocement et plus intensément la performance aux formes non verbales qu'à la forme verbale du test. Il induit également une importante augmentation du nombre de fausses reconnaissances pour les formes non verbales.

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Résumé Introduction et but: Les accidents vasculaires cérébraux (AVC) ischémiques thalamiques sont traditionnellement classés en quatre territoires : antérieur (polaire ou tubérothalamique), paramédian (ou thalamo-perforant), inférolatéral (ou thalamo-genouillé) et postérieur. Le but de cette thèse est de déterminer, à l'aide des techniques d'imagerie actuelles, si cette classification est appropriée ou si il existe d'autres territoires à la jonction entre les précédents territoires. Méthode: Nous avons étudié les 3712 patients hospitalisés pour un premier AVC dans le service de neurologie du CHUV à Lausanne et inclus dans le « Lausanne Stroke Registry » entre 1990 et 2002. Parmi les 71 patients avec un infarctus thalamique confirmé par IRM, nous avons sélectionné tous les patients présentant un AVC hors des quatre territoires classiques en étudiant leur tableau clinique, étiologique et radiologique. Résultats: 21 patients (30% des patients avec AVC thalamiques) avaient un AVC hors des quatre territoires classiques, permettant de délimiter trois nouveaux territoires. 1) territoire anteromédian (9 patients (13%)), atteignant la partie postérieure du territoire antérieur et la partie antérieure du territoire paramédian, avec en premier lieu des troubles cognitifs (principalement troubles dysexecutifs, amnésie antérograde ainsi qu'une aphasie dans les lésions gauches). L'étiologie principale était cardio-embolique. 2) territoire central (4 patients (6%)), atteignant la partie centrale du thalamus provoquant différents signes neurologiques et neuropsychologiques, reflétant l'atteinte de différentes structures. La cause la plus fréquente était microangiopathique. 3) territoire posterolateral (8 patients (8%)), atteignant la partie postérieure du territoire inférolatéral et la partie antérieure du territoire postérieur provoquant en premier lieu une hémihypesthesie mais aussi une hémiataxie ainsi que des troubles dysexécutifs et une aphasie dans les lésions gauches. Les étiologies les plus fréquentes étaient artério-artérielle et microangiopathique. Conclusions: Nous décrivons trois nouvelles variantes topographiques d'AVC thalamiques avec des tableaux cliniques et étiologiques distincts. Nous postulons que ces variantes sont le résultat de variations de la vascularisation thalamique ou reflètent une atteinte ischémique jonctionnelle. Abstract Background and Purpose -Thalamic infarcts have traditionally been classified into 4 territories: anterior, paramedian, inferolateral, and posterior. The purpose of this study was to review this classical versus variant distribution in patients with thalamic stroke. Methods - We reviewed all patients with a first clinical stroke included in the Lausanne Stroke Registry between 1990 and 2002. Among 71 patients with an acute stroke isolated to the thalamus confirmed by MRI, we selected all patients with lesions outside the classical territories and studied their clinical, etiological, and radiological features. Results - A total of 21 patients (30% of all thalamic stroke patients) showed infarction outside the classical territories, allowing us to delineate 3 variant distributions: (1) Anteromedian territory (9 patients [13%]) involving anterior and paramedian territories, with predominantly cognitive impairment, including executive dysfunction, anterograde amnesia, and aphasia in left-sided or bilateral lesions. The most frequent stroke mechanism was cardiac embolism. (2) Central territory (4 patients [6%]), with lesions on the central part of the thalamus, resulting in a variety of neurological and neuropsychological signs, reflecting the involvement of several adjacent structures. Microangiopathy was the most frequent etiology. (3) Posterolateral territory (8 patients [11%]), involving inferolateral and posterior territories, with hemihypesthesia as the most frequent manifestation, followed by hemiataxia, executive dysfunction, and aphasia in left-sided lesions. Artery-to-artery embolism and microangiopathy were the main stroke mechanisms. Conclusions - We describe 3 variant topographic patterns of thalamic infarction with distinct manifestations and etiologies. We postulate that these infarcts are the result of a variation in thalamic arterial supply or reflect borderzone ischemia.

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GENDER EMPOWERMENT: EFFECTS OF GODS, GEOGRAPHY, AND GDP¦Fenley, M., & Antonakis, J.¦ABSTRACT¦We examined the determinants of women's empowerment in the economy and political leadership in 178 countries. Given the androcentric nature of most religions, we hypothesized that high degrees of country-level theistic belief create social conditions that impede the progression of women to power. The dependent variable was the Gender Empowerment index of the United Nations Development Program, which captures the participation of women in political leadership, management, and their share of national income. Controlling for GDP per capita as well as the fixed-effects of the dominant type of religion and legal origin and instrumenting all endogenous variables with geographic or historical variables, our results show that atheism has a significant positive effect on gender empowerment. These results are driven by the rule of law, which in addition to being a catalyst for economic development, appears to crowd-out the informal regulation of behavior due to religious norms.¦DEVELOPING WOMEN LEADERS: COMPARING A TRANSFORMATIONAL AND A CHARISMATIC LEADERSHIP INTERVENTION¦Fenley, M., Jacquart, P., & Antonakis, J.¦ABSTRACT¦Along with a gender imbalance in leadership role occupancy, most leadership interventions have been conducted with samples of men. We conducted an experiment wherein we assigned female participants (n = 38, mean age = 35 years) to one of two conditions: Transformational (i.e., "standard") leadership training or charismatic leadership training. The two interventions were essentially equivalent, except that we also focused on developing the "charismatic leadership tactics" (e.g., rhetorical skills) of participants in the charismatic condition. After the interventions, we randomly assigned participants into problem-solving teams that required extensive interaction. Each team had an equal number of participants having received transformational training or charismatic training. At the end of the team exercises, participants rated each of their team members on a leadership prototypicality measure. Results indicated that those who received charismatic training scored higher (a) on prototypicality (standardized  = .42) and (b) on a test of declarative knowledge of charismatic rhetorical strategies (i.e., a manipulation check, standardized  = .76). Furthermore, the score on the test fully mediated the effect of the treatment on prototypicality (standardized indirect  = .32). We discuss the importance and practical implications of these results.¦CHANGING ATTITUDES TOWARDS WOMEN IN A MALE SEX-TYPE WORK ENVIRONMENT: EVIDENCE FROM A FIELD EXPERIMENT IN EUROPEAN ATHLETICS¦Fenley, M.¦ABSTRACT¦Most sports organizations have a similar gender gap in leadership as do the majority of non-sport organizations. Women's careers sputter somewhere at coaching level positions and few women obtain top leadership positions. Greater awareness of gender inequalities in general, and in leadership in particular, could decrease gender discrimination and increase women's presence at upper levels. The goal of this study was to evaluate the impact of an intervention using an online gender awareness exercise. Participants (n = 1,001 participants, n = 32 countries) were randomly assigned to one of eight conditions in a 2 (a discriminating perspective-taking story or a non-discriminating perspective-taking story) by 2 (gender quiz or no gender quiz) by 2 (diversity quiz or no diversity quiz) factorial design. The results show that the online perspective taking exercise changed initial sexist attitudes. Participants having taken a diversity quiz had less sexist attitudes (as measured by the Modern- and Old-fashioned sexism scale) than did participants who did not take the diversity quiz (irrespective of perspective-taking story). The combination of having taken a diversity quiz with a gender quiz had the biggest impact on attitudes for the non-discriminating story.

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Memory and effector T cells have the potential to counteract cancer progression, but often fail to control the disease, essentially because of three main stumbling blocks. First, clonal deletion leads to relatively low numbers or low-to-intermediate T cell receptor (TCR) affinity of self/tumor-specific T cells. Second, the poor innate immune stimulation by solid tumors is responsible for inefficient priming and boosting. Third, T cells are suppressed in the tumor microenvironment by inhibitory signals from other immune cells, stroma and tumor cells, which induces T cell exhaustion, as demonstrated in metastases of melanoma patients. State-of-the-art adoptive cell transfer and active immunotherapy can partially overcome the three stumbling blocks. The reversibility of T cell exhaustion and novel molecular insights provide the basis for further improvements of clinical immunotherapy.

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Prospective comparative evaluation of patent V blue, fluorescein and (99m)TC-nanocolloids for intraoperative sentinel lymph node (SLN) mapping during surgery for non-small cell lung cancer (NSCLC). Ten patients with peripherally localised clinical stage I NSCLC underwent thoracotomy and peritumoral subpleural injection of 2 ml of patent V blue dye, 1 ml of 10% fluorescein and 1ml of (99m)Tc-nanocolloids (0.4 mCi). The migration and spatial distribution pattern of the tracers was assessed by direct visualisation (patent V blue), visualisation of fluorescence signalling by a lamp of Wood (fluorescein) and radioactivity counting with a hand held gamma-probe ((99m)Tc-nanocolloids). Lymph nodes at interlobar (ATS 11), hilar (ATS 10) and mediastinal (right ATS 2,4,7; left ATS 5,6,7) levels were systematically assessed every 10 min up to 60 min after injection, followed by lobectomy and formal lymph node dissection. Successful migration from the peritumoral area to the mediastinum was observed for all three tracers up to 60 min after injection. The interlobar lympho-fatty tissue (station ATS 11) revealed an early and preferential accumulation of all three tracers for all tumours assessed and irrespective of the tumour localisation. However, no preferential accumulation in one or two distinct lymph nodes was observed up to 60 min after injection for all three tracers assessed. Intraoperative SLN mapping revealed successful migration of the tracers from the site of peritumoral injection to the mediastinum, but in a diffuse pattern without preferential accumulation in sentinel lymph nodes.

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Background: Nanoparticle (NPs) functionalization has been shown to affect their cellular toxicity. To study this, differently functionalized silver (Ag) and gold (Au) NPs were synthesised, characterised and tested using lung epithelial cell systems. Mehtods: Monodispersed Ag and Au NPs with a size range of 7 to 10 nm were coated with either sodium citrate or chitosan resulting in surface charges from ¿50 mV to +70 mV. NP-induced cytotoxicity and oxidative stress were determined using A549 cells, BEAS-2B cells and primary lung epithelial cells (NHBE cells). TEER measurements and immunofluorescence staining of tight junctions were performed to test the growth characteristics of the cells. Cytotoxicity was measured by means of the CellTiter-Blue ® and the lactate dehydrogenase assay and cellular and cell-free reactive oxygen species (ROS) production was measured using the DCFH-DA assay. Results: Different growth characteristics were shown in the three cell types used. A549 cells grew into a confluent mono-layer, BEAS-2B cells grew into a multilayer and NHBE cells did not form a confluent layer. A549 cells were least susceptible towards NPs, irrespective of the NP functionalization. Cytotoxicity in BEAS-2B cells increased when exposed to high positive charged (+65-75 mV) Au NPs. The greatest cytotoxicity was observed in NHBE cells, where both Ag and Au NPs with a charge above +40 mV induced cytotoxicity. ROS production was most prominent in A549 cells where Au NPs (+65-75 mV) induced the highest amount of ROS. In addition, cell-free ROS measurements showed a significant increase in ROS production with an increase in chitosan coating. Conclusions: Chitosan functionalization of NPs, with resultant high surface charges plays an important role in NP-toxicity. Au NPs, which have been shown to be inert and often non-cytotoxic, can become toxic upon coating with certain charged molecules. Notably, these effects are dependent on the core material of the particle, the cell type used for testing and the growth characteristics of these cell culture model systems.

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This study examined the electromyographic, cerebral and muscle hemodynamic responses during intermittent isometric contractions of biceps brachii at 20, 40, and 60% of maximal voluntary contraction (MVC). Eleven volunteers completed 2 min of intermittent isometric contractions (12/min) at an elbow angle of 90° interspersed with 3 min rest between intensities in systematic order. Surface electromyography (EMG) was recorded from the right biceps brachii and near infrared spectroscopy (NIRS) was used to simultaneously measure left prefrontal and right biceps brachii oxyhemoglobin (HbO2), deoxyhemoglobin (HHb), and total hemoglobin (Hbtot). Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv) bilaterally. Finger photoplethysmography was used to record beat-to-beat blood pressure and heart rate. EMG increased with force output from 20 to 60% MVC (P < 0.05). Cerebral HbO2 and Hbtot increased while HHb decreased during contractions with differences observed between 60% vs. 40% and 20% MVC (P < 0.05). Muscle HbO2 decreased while HHb increased during contractions with differences being observed among intensities (P < 0.05). Muscle Hbtot increased from rest at 20% MVC (P < 0.05), while no further change was observed at 40 and 60% MVC (P > 0.05). MCAv increased from rest to exercise but was not different among intensities (P > 0.05). Force output correlated with the root mean square EMG and changes in muscle HbO2 (P < 0.05), but not changes in cerebral HbO2 (P > 0.05) at all three intensities. Force output declined by 8% from the 1st to the 24th contraction only at 60% MVC and was accompanied by systematic increases in RMS, cerebral HbO2 and Hbtot with a leveling off in muscle HbO2 and Hbtot. These changes were independent of alterations in mean arterial pressure. Since cerebral blood flow and oxygenation were elevated at 60% MVC, we attribute the development of fatigue to reduced muscle oxygen availability rather than impaired central neuronal activation.

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ABSTRACT My study seeks to answer the main question: "how does entrepreneurs' social capital positively and negatively affect their resource mobilization efforts, and exploitation of entrepreneurial opportunity?" To answer this question, I develop a model for examining positive and negative effects of social capital on resource accumulation by entrepreneurs, and the subsequent effect of resource accumulation on the exploitation of entrepreneurial opportunity, and utilize data from Africa to ëmpirically test the relationships in this model. Developing nations are a suitable context because: a) They require entrepreneurship for economic development, b) They have received less attention in management and entrepreneurship research, c) Because of inadequately-developed institutions, entrepreneurs from developing nations face major resource mobilization challenges hence they often turn to their social ties for resources, and d) The communalistic and collectivistic nature of most developing nations -encouraging support and sharing of resources- may help us better understand how society's values and structures may contribute and also deduct firm resources. My study reveals that social capital contributes resources to entrepreneurs in developing nations at a cost that takes away resources, and that more resources but lower costs facilitate entrepreneurial opportunity exploitation. For entrepreneurs in developing nations, large networks, greater shared identity, and more trust are beneficial. To increase chances of raising more resources, entrepreneurs from communalistic societies should include network members from outside their communities. Besides providing financial support, policy-makers should develop training programs and advisory services on configuration of entrepreneurs' networks so as to achieve more resources at a low cost. My study insights can help improve entrepreneurs' resource accumulation efforts and the subsequent growth of their firms, leading to the overall economic growth of developing nations.

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The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.

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The aim of the present study is to determine the level of correlation between the 3-dimensional (3D) characteristics of trabecular bone microarchitecture, as evaluated using microcomputed tomography (μCT) reconstruction, and trabecular bone score (TBS), as evaluated using 2D projection images directly derived from 3D μCT reconstruction (TBSμCT). Moreover, we have evaluated the effects of image degradation (resolution and noise) and X-ray energy of projection on these correlations. Thirty human cadaveric vertebrae were acquired on a microscanner at an isotropic resolution of 93μm. The 3D microarchitecture parameters were obtained using MicroView (GE Healthcare, Wauwatosa, MI). The 2D projections of these 3D models were generated using the Beer-Lambert law at different X-ray energies. Degradation of image resolution was simulated (from 93 to 1488μm). Relationships between 3D microarchitecture parameters and TBSμCT at different resolutions were evaluated using linear regression analysis. Significant correlations were observed between TBSμCT and 3D microarchitecture parameters, regardless of the resolution. Correlations were detected that were strongly to intermediately positive for connectivity density (0.711≤r(2)≤0.752) and trabecular number (0.584≤r(2)≤0.648) and negative for trabecular space (-0.407 ≤r(2)≤-0.491), up to a pixel size of 1023μm. In addition, TBSμCT values were strongly correlated between each other (0.77≤r(2)≤0.96). Study results show that the correlations between TBSμCT at 93μm and 3D microarchitecture parameters are weakly impacted by the degradation of image resolution and the presence of noise.

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To compare the prediction of hip fracture risk of several bone ultrasounds (QUS), 7062 Swiss women > or =70 years of age were measured with three QUSs (two of the heel, one of the phalanges). Heel QUSs were both predictive of hip fracture risk, whereas the phalanges QUS was not. INTRODUCTION: As the number of hip fracture is expected to increase during these next decades, it is important to develop strategies to detect subjects at risk. Quantitative bone ultrasound (QUS), an ionizing radiation-free method, which is transportable, could be interesting for this purpose. MATERIALS AND METHODS: The Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture Risk (SEMOF) study is a multicenter cohort study, which compared three QUSs for the assessment of hip fracture risk in a sample of 7609 elderly ambulatory women > or =70 years of age. Two QUSs measured the heel (Achilles+; GE-Lunar and Sahara; Hologic), and one measured the heel (DBM Sonic 1200; IGEA). The Cox proportional hazards regression was used to estimate the hazard of the first hip fracture, adjusted for age, BMI, and center, and the area under the ROC curves were calculated to compare the devices and their parameters. RESULTS: From the 7609 women who were included in the study, 7062 women 75.2 +/- 3.1 (SD) years of age were prospectively followed for 2.9 +/- 0.8 years. Eighty women reported a hip fracture. A decrease by 1 SD of the QUS variables corresponded to an increase of the hip fracture risk from 2.3 (95% CI, 1.7, 3.1) to 2.6 (95% CI, 1.9, 3.4) for the three variables of Achilles+ and from 2.2 (95% CI, 1.7, 3.0) to 2.4 (95% CI, 1.8, 3.2) for the three variables of Sahara. Risk gradients did not differ significantly among the variables of the two heel QUS devices. On the other hand, the phalanges QUS (DBM Sonic 1200) was not predictive of hip fracture risk, with an adjusted hazard risk of 1.2 (95% CI, 0.9, 1.5), even after reanalysis of the digitalized data and using different cut-off levels (1700 or 1570 m/s). CONCLUSIONS: In this elderly women population, heel QUS devices were both predictive of hip fracture risk, whereas the phalanges QUS device was not.

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In this article we propose a novel method for calculating cardiac 3-D strain. The method requires the acquisition of myocardial short-axis (SA) slices only and produces the 3-D strain tensor at every point within every pair of slices. Three-dimensional displacement is calculated from SA slices using zHARP which is then used for calculating the local displacement gradient and thus the local strain tensor. There are three main advantages of this method. First, the 3-D strain tensor is calculated for every pixel without interpolation; this is unprecedented in cardiac MR imaging. Second, this method is fast, in part because there is no need to acquire long-axis (LA) slices. Third, the method is accurate because the 3-D displacement components are acquired simultaneously and therefore reduces motion artifacts without the need for registration. This article presents the theory of computing 3-D strain from two slices using zHARP, the imaging protocol, and both phantom and in-vivo validation.