180 research outputs found

    Роль когнитивных компонентов в формировании иноязычной компетенции

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    Актуализация когнитивного компонента иноязычной компетенции направлена на приобретение обучающимися нового учебного опыта на основе овладения метакогнитивными стратегиями осуществления учебной деятельности, что обуславливает успешность процесса формирования предметных навыков, а также личностное развитие обучающихся в процессе решения учебных задач

    Диффузия водорода в палладии: рас-четы из первых принципов

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    Целью данной работы является теоретическое исследование профилей диффузионных барьеров и температурной зависимости коэффициентов диффузии водорода в палладии. По результатам расчетов наиболее вероятным механизмом диффузии атома Н в Pd являются диффузионные скачки через октаэдрические – тетраэдрические – октаэдрическе междоузлия (величина барьеров в этих случаях составляет ~ 0,39 и 0,16 эВ, соответственно). Для большинства диффузионных скачков, высота барьеров в твердом растворе Pd16H2 ниже, чем высота барьеров в твердом растворе Pd16H. При температурах 600-900 K, значения коэффициентов диффузии водорода вдоль направлений [110] и [001] решетки Pd хорошо согласуются с результатами других работ.The purpose of this study is theoretically study of the diffusion barrier profiles and the temperature dependence of the hydrogen diffusion coefficients in palladium. According to the results of our calculations, diffusion jumps through octahedral-tetrahedral-octahedral interstitial sites are the most probable mechanism of diffusion of the H atom in Pd (the barrier in these cases amounts to ~ 0.39 and 0.16 eV, respectively). For most diffusion jumps, the value of the barriers in a solid solution of Pd16H2 is lower than the value of the barriers in a solid solution of Pd16H. At temperatures of 600-900 K, the values of the hydrogen diffusion coefficients along the [110] and [001] directions of the Pd lattice agree well with the results of other studies

    Evaluating an implementation strategy in cardiovascular prevention to improve prescribing of statins in Germany: an intention to treat analysis

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    BACKGROUND: The prescription of statins is an evidence-based treatment to reduce the risk of cardiovascular events in patients with elevated cardiovascular risk or with a cardiovascular disorder (CVD). In spite of this, many of these patients do not receive statins. METHODS: We evaluated the impact of a brief educational intervention in cardiovascular prevention in primary care physicians' prescribing behaviour regarding statins beyond their participation in a randomised controlled trial (RCT). For this, prescribing data of all patients >= 35 years who were counselled before and after the study period were analysed (each n > 75000). Outcome measure was prescription of Hydroxymethylglutaryl-CoA Reductase Inhibitors (statins) corresponding to patients' overall risk for CVD. Appropriateness of prescribing was examined according to different risk groups based on the Anatomical Therapeutic Chemical Classification System (ATC codes). RESULTS: There was no consistent association between group allocation and statin prescription controlling for risk status in each risk group before and after study participation. However, we found a change to more significant drug configurations predicting the prescription of statins in the intervention group, which can be regarded as a small intervention effect. CONCLUSION: Our results suggest that an active implementation of a brief evidence-based educational intervention does not lead to prescription modifications in everyday practice. Physician's prescribing behaviour is affected by an established health care system, which is not easy to change.Trial registration: ISRCTN71348772

    Heartburn or angina? Differentiating gastrointestinal disease in primary care patients presenting with chest pain: a cross sectional diagnostic study

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    <p>Abstract</p> <p>Background</p> <p>Gastrointestinal (GI) disease is one of the leading aetiologies of chest pain in a primary care setting. The aims of the study are to describe clinical characteristics of GI disease causing chest pain and to provide criteria for clinical diagnosis.</p> <p>Methods</p> <p>We included 1212 consecutive patients with chest pain aged 35 years and older attending 74 general practitioners (GPs). GPs recorded symptoms and findings of each patient and provided follow up information. An independent interdisciplinary reference panel reviewed clinical data of each patient and decided about the aetiology of chest pain. Multivariable regression analysis was performed to identify clinical predictors that help to rule in or out the diagnosis of GI disease and Gastroesophageal Reflux Disease (GERD).</p> <p>Results</p> <p>GI disease was diagnosed in 5.8% and GERD in 3.5% of all patients. Most patients localised the pain retrosternal (71.8% for GI disease and 83.3% for GERD). Pain worse with food intake and retrosternal pain radiation were associated positively with both GI disease and GERD; retrosternal pain localisation, vomiting, burning pain, epigastric pain and an average pain episode < 1 hour were associated positively only with GI disease. Negative associations were found for localized muscle tension (GI disease and GERD) and pain getting worse on exercise, breathing, movement and pain location on left side (only GI disease).</p> <p>Conclusions</p> <p>This study broadens the knowledge about the diagnostic accuracy of selected signs and symptoms for GI disease and GERD and provides criteria for primary care practitioners in rational diagnosis.</p

    Circuit mechanisms for the chemical modulation of cortex-wide network interactions and behavioral variability

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    Influential theories postulate distinct roles of catecholamines and acetylcholine in cognition and behavior. However, previous physiological work reported similar effects of these neuromodulators on the response properties (specifically, the gain) of individual cortical neurons. Here, we show a double dissociation between the effects of catecholamines and acetylcholine at the level of large-scale interactions between cortical areas in humans. A pharmacological boost of catecholamine levels increased cortex-wide interactions during a visual task, but not rest. An acetylcholine boost decreased interactions during rest, but not task. Cortical circuit modeling explained this dissociation by differential changes in two circuit properties: the local excitation-inhibition balance (more strongly increased by catecholamines) and intracortical transmission (more strongly reduced by acetylcholine). The inferred catecholaminergic mechanism also predicted noisier decision-making, which we confirmed for both perceptual and value-based choice behavior. Our work highlights specific circuit mechanisms for shaping cortical network interactions and behavioral variability by key neuromodulatory systems

    Mapping the spatial distribution of NO2 with in situ and remote sensing instruments during the Munich NO2 imaging campaign

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    We present results from the Munich Nitrogen dioxide (NO2) Imaging Campaign (MuNIC), where NO2 near-surface concentrations (NSCs) and vertical column densities (VCDs) were measured with stationary, mobile, and airborne in situ and remote sensing instruments in Munich, Germany. The most intensive day of the campaign was 7 July 2016, when the NO2 VCD field was mapped with the Airborne Prism Experiment (APEX) imaging spectrometer. The spatial distribution of APEX VCDs was rather smooth, with a horizontal gradient between lower values upwind and higher values downwind of the city center. The NO2 map had no pronounced source signatures except for the plumes of two combined heat and power (CHP) plants. The APEX VCDs have a fair correlation with mobile multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations from two vehicles conducted on the same afternoon (r=0.55). In contrast to the VCDs, mobile NSC measurements revealed high spatial and temporal variability along the roads, with the highest values in congested areas and tunnels. The NOx emissions of the two CHP plants were estimated from the APEX observations using a mass-balance approach. The NOx emission estimates are consistent with CO2 emissions determined from two ground-based Fourier transform infrared (FTIR) instruments operated near one CHP plant. The estimates are higher than the reported emissions but are probably overestimated because the uncertainties are large, as conditions were unstable and convective with low and highly variable wind speeds. Under such conditions, the application of mass-balance approaches is problematic because they assume steady-state conditions. We conclude that airborne imaging spectrometers are well suited for mapping the spatial distribution of NO2 VCDs over large areas. The emission plumes of point sources can be detected in the APEX observations, but accurate flow fields are essential for estimating emissions with sufficient accuracy. The application of airborne imaging spectrometers for studying NSCs is less straightforward and requires us to account for the non-trivial relationship between VCDs and NSCs

    Геоэкологическая характеристика и элементный состав листьев тополя территории г. Тюмень

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    Работа направлена на изучение элементного состава листьев тополя как биогеохимического индикатора состояния окружающей среды городов с выраженной специализацией. Исследование проведено на примере города Тюмень.The work is directed at studying the elemental composition of poplar leaves as a biogeochemical indicator of the state of the environment of cities with a pronounced specialization. The study was conducted on the example of the city of Tyumen

    Accuracy of General Practitioners’ Assessment of Chest Pain Patients for Coronary Heart Disease in Primary Care: Cross-sectional Study with Follow-up

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    Aim To estimate how accurately general practitioners’ (GP) assessed the probability of coronary heart disease in patients presenting with chest pain and analyze the patient management decisions taken as a result. Methods During 2005 and 2006, the cross-sectional diagnostic study with a delayed-type reference standard included 74 GPs in the German state of Hesse, who enrolled 1249 consecutive patients presenting with chest pain. GPs recorded symptoms and findings for each patient on a report form. Patients and GPs were contacted 6 weeks and 6 months after the patients’ visit to the GP. Data on chest complaints, investigations, hospitalization, and medication were reviewed by an independent panel, with coronary heart disease being the reference condition. Diagnostic properties (sensitivity, specificity, and predictive values) of the GPs’ diagnoses were calculated. Results GPs diagnosed coronary heart disease with the sensitivity of 69% (95% confidence interval [CI], 62-75) and specificity of 89% (95% CI, 87-91), and acute coronary syndrome with the sensitivity of 50% (95% CI, 36-64) and specificity of 98% (95% CI, 97-99). They assumed coronary heart disease in 245 patients, 41 (17%) of whom were referred to the hospital, 77 (31%) to a cardiologist, and 162 (66%) to electrocardiogram testing. Conclusions GPs’ evaluation of chest pain patients, based on symptoms and signs alone, was not sufficiently accurate for diagnosing or excluding coronary heart disease or acute coronary syndrome

    Validation of Sentinel-5P TROPOMI tropospheric NO2 products by comparison with NO2 measurements from airborne imaging, ground-based stationary, and mobile car DOAS measurements during the S5P-VAL-DE-Ruhr campaign

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    Airborne imaging differential optical absorption spectroscopy (DOAS), ground-based stationary and car DOAS measurements were conducted during the S5P-VAL-DE-Ruhr campaign in September 2020. The campaign area is located in the Rhine-Ruhr region of North Rhine-Westphalia, Western Germany, which is a pollution hotspot in Europe comprising urban and large industrial emitters. The measurements are used to validate space-borne NO2 tropospheric vertical column density data products from the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI). Seven flights were performed with the airborne imaging DOAS instrument for measurements of atmospheric pollution (AirMAP), providing measurements which were used to create continuous maps of NO2 in the layer below the aircraft. These flights cover many S5P ground pixels within an area of 30 km x 35 km and were accompanied by ground-based stationary measurements and three mobile car DOAS instruments. Stationary measurements were conducted by two Pandora, two zenith-sky and two MAX-DOAS instruments distributed over three target areas. Ground-based stationary and car DOAS measurements are used to evaluate the AirMAP tropospheric NO2 vertical column densities and show high Pearson correlation coefficients of 0.87 and 0.89 and slopes of 0.93 &plusmn; 0.09 and 0.98 &plusmn; 0.02 for the stationary and car DOAS, respectively. Having a spatial resolution of about 100 m x 30 m, the AirMAP tropospheric NO2 vertical column density (VCD) data creates a link between the ground-based and the TROPOMI measurements with a resolution of 3.5 km x 5.5 km and is therefore well suited to validate the TROPOMI tropospheric NO2 VCD. The measurements on the seven flight days show strong NO2 variability, which is dependent on the different target areas, the weekday, and the meteorological conditions. The AirMAP campaign dataset is compared to the TROPOMI NO2 operational off-line (OFFL) V01.03.02 data product, the reprocessed NO2 data, using the V02.03.01 of the official L2 processor, provided by the Product Algorithm Laboratory (PAL), and several scientific TROPOMI NO2 data products. The TROPOMI data products and the AirMAP data are highly correlated with correlation coefficients between 0.72 and 0.87, and slopes of 0.38 &plusmn; 0.02 to 1.02 &plusmn; 0.07. On average, TROPOMI tropospheric NO2 VCDs are lower than the AirMAP NO2 results. The slope increased from 0.38 &plusmn; 0.02 for the operational OFFL V01.03.02 product to 0.83 &plusmn; 0.06 after the improvements in the retrieval of the PAL V02.03.01 product were implemented. Different auxiliary data, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity and the cloud treatment, are investigated using scientific TROPOMI tropospheric NO2 VCD data products to evaluate their impact on the operational TROPOMI NO2 VCD data product. The comparison of the AirMAP campaign dataset to the scientific data products shows that the choice of surface reflectivity data base has a minor impact on the tropospheric NO2 VCD retrieval in the campaign region and season. In comparison, the replacement of the a priori NO2 profile in combination with the improvements in the retrieval of the PAL V02.03.01 product regarding cloud heights has a major impact on the tropospheric NO2 VCD retrieval and increases the slope from 0.88 &plusmn; 0.06 to 1.00 &plusmn; 0.07. This study demonstrates that the underestimation of the TROPOMI tropospheric NO2 VCD product with respect to the validation dataset has been and can be further significantly improved.</p
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