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Submitted here is a material on the review of standards and rules on the certification of tech machinery in the republic of Zambia., Представлены материалы по обзору стандартов и правилам сертификации техники в условиях Республике Замбия.

The article is devoted to a comparative analysis of the technical regulation systems of Russia and Kazakhstan. The article will examine in detail the law on technical regulation. The paper compares the draft technical regulation bill in these countries., Статья посвящена сравнительному анализу систем технического регулирования России и Казахстана. В статье подробно будет рассмотрен закон о техническом регулировании. В работе сравнивается законопроект по техническому регулированию в этих странах.

Анализ конструкций современных отечественных и зарубежных сельскохозяйственных машин показал, что одной из наиболее ответственных систем, влияющих на надежность техники, является объемный гидропривод. Примером такого гидропривода является гидростатическая трансмиссия, состоящая из сложных дорогостоящих аксиально-поршневых агрегатов. По данным научно-технической литературы доля объемных гидроприводов в трансмиссиях современной технике для АПК не менее 35 %, а на отказы гидропривода в доремонтный период эксплуатации приходится до 20 % от общего числа отказов машин [ 1, 3]., Analysis of the designs of modern domestic and foreign agricultural machines has shown that one of the most important systems that affect the reliability of equipment is a volumetric hydraulic drive. An example of such a hydraulic drive is a hydrostatic transmission consisting of complex, expensive axial-piston units. According to scientific and technical literature, the share of volume hydraulic drives in transmissions of modern equipment for agriculture is not less than 35 %, and hydraulic drive failures in the pre-repair period of operation account for up to 20 % of the total number of machine failures [ 1, 3]. At the present stage of development of agricultural machinery, agricultural machinery is faced with the task of developing and producing machines that allow maximum saving of raw materials, fuel and energy resources at the stages of production, processing and use of agricultural products. In the conditions of modern production, productivity, efficiency and reliability of agricultural machinery increases, their mass per unit of power decreases, and the accuracy of manufacturing products increases.

The energetics of mixing and defect ordering in solid solutions of fluorite-structured ThO2 with oxides of trivalent cations (Sc, In, Y, Nd, and La) are investigated by electronic density-functional theory (DFT). Through DFT calculations of structures enumerated by lattice-algebra techniques, we identify the lowest energy patterns for defect clustering for four separate dopant concentrations. The most stable structures are characterized by a repulsive interaction between nearest-neighbor vacancies on the oxygen sublattice. The enthalpies of formation with respect to constituent oxides are positive for all dopants considered, and show a tendency to decrease in magnitude as the size and electronegativity of the trivalent dopant decrease. Due to the small positive formation enthalpies and low oxygen-vacancy binding energy with La dopants, La2 O3 -ThO2 solid solutions are predicted to have relatively high ionic conductivities relative to those for the other aliovalent dopants considered. Our results are compared with those for the more widely studied ZrO2 and CeO2 fluorite-structured solid solutions with trivalent cations. © 2010 The American Physical Society.

The energetics of mixing and defect ordering in solid solutions of fluorite-structured ThO2 with oxides of trivalent cations (Sc, In, Y, Nd, and La) are investigated by electronic density-functional theory (DFT). Through DFT calculations of structures enumerated by lattice-algebra techniques, we identify the lowest energy patterns for defect clustering for four separate dopant concentrations. The most stable structures are characterized by a repulsive interaction between nearest-neighbor vacancies on the oxygen sublattice. The enthalpies of formation with respect to constituent oxides are positive for all dopants considered, and show a tendency to decrease in magnitude as the size and electronegativity of the trivalent dopant decrease. Due to the small positive formation enthalpies and low oxygen-vacancy binding energy with La dopants, La2 O3 -ThO2 solid solutions are predicted to have relatively high ionic conductivities relative to those for the other aliovalent dopants considered. Our results are compared with those for the more widely studied ZrO2 and CeO2 fluorite-structured solid solutions with trivalent cations. © 2010 The American Physical Society.

Europe is, after Asia, the second largest producer of wheat in the world, and provides the largest share of barley. Wheat (and to a similar extent, barley) production in Europe increased by more than 6-fold during the 20th century. During the first half of the 20th century, this was driven by expanding the harvested area. This was followed, from the mid-20th century, by a massive increase in productivity that in many regions has stalled since 2000. However, it remains unclear what role climatic factors have played in these changes. Understanding the net impact of climatic trends over the past century would also aid in our understanding of the potential impact of future climate changes and in assessments of the potential for adaptation across Europe. In this study, we compiled information from several sources on winter wheat and spring barley yields and climatological data from 12 countries/regions covering the period from 1901-2012. The studied area includes the majority of climatic regions in which wheat and barley are grown (from central Italy to Finland). We hypothesized that changes in climatic conditions have led to measurable shifts in climate-yield relationships over the past 112 yr, and that presently grown wheat and barley show a more pronounced response to adverse weather conditions compared to crops from the early 20th century. The results confirm that climate-yield relationships have changed significantly over the period studied, and that in some regions, different predictors have had a greater effect on yields in recent times (between 1991 and 2012) than in previous decades. It is likely that changes in the climate-yield relationship at the local level might be more pronounced than those across the relatively large regions used in this study, as the latter represents aggregations of yields from various agroclimatic and pedoclimatic conditions that may show opposing trends.

Background and Purpose: After numerous attempts to prove efficacy for endovascular treatment of ischemic stroke, a series of recent randomized controlled clinical trials (RCTs) established fast mechanical thrombectomy (MT) as a safe and effective novel treatment for emergent large vessel occlusion (ELVO) in the anterior cerebral circulation. Methods: We reviewed five recent RCTs that evaluated the safety and efficacy of MT in ELVO patients and captured available information on recanalization/reperfusion, symptomatic intracranial hemorrhage (sICH), clinical outcome, and mortality. MT was performed with stent retrievers, aspiration techniques, or a combination of these endovascular approaches. We applied meta-analytical methodology to evaluate the pooled effect of MT on recanalization/reperfusion, sICH, functional independence (modified Rankin scale score of 0-2) and 3-month mortality rates in comparison to best medical therapy (BMT). Results: MT was associated with increased likelihood of complete recanalization/reperfusion (RR: 2.22; 95%CI: 1.89-2.62; P < 0.00001) and 3-month functional independence (RR: 1.72; 95%CI: 1.48-1.99; P < 0.00001) without any heterogeneity across trials (I2 = 0%). The absolute benefit increase in MT for complete recanalization/reperfusion and functional independence was 44 (NNT = 2) and 16 (NNT = 6), respectively. MT was not associated with increased risk of 3-month mortality (15% with MT vs. 19% with BMT) and sICH (4.6% with MT vs. 4.3% with BMT), while small heterogeneity was detected across the included trials (I2 < 25%). Conclusions: MT is a safe and highly effective treatment for patients with ELVO in the anterior circulation. For every six ELVO patients treated with MT three more will achieve complete recanalization at 24 h following symptom onset and one more will be functionally independent at 3 months in comparison to BMT. MT is a safe and highly effective treatment for patients with emergent large vessel occlusion (ELVO) in the a, SCOPUS: ar.j, info:eu-repo/semantics/published

Objective: Even though statin pretreatment is associated with better functional outcomes and lower risk of mortality in acute ischemic stroke, there are limited data evaluating this association in acute ischemic stroke due to large artery atherosclerosis (LAA), which carries the highest risk of early stroke recurrence. Methods: Consecutive patients with acute LAA were prospectively evaluated from 7 tertiary-care stroke centers during a 3-year period. Statin pretreatment, demographics, vascular risk factors, and admission and discharge stroke severity were recorded. The outcome events of interest were neurologic improvement during hospitalization (quantified as the relative decrease in NIH Stroke Scale score at discharge in comparison to hospital admission), favorable functional outcome (FFO) (defined as modified Rankin Scale score of 0-1), recurrent stroke, and death at 1 month. Statistical analyses were performed using univariable and multivariable Cox regression models adjusting for potential confounders. All analyses were repeated following propensity score matching. Results: Statin pretreatment was documented in 192 (37.2%) of 516 consecutive patients with LAA (mean age: 65 ± 13 years; 60.8% men; median NIH Stroke Scale score: 9 points, interquartile range: 5-18). Statin pretreatment was associated with greater neurologic improvement during hospitalization and higher rates of 30-day FFO in unmatched and matched (odds ratio for FFO: 2.44; 95% confidence interval [CI]: 1.07-5.53) analyses. It was also related to lower risk of 1-month mortality and stroke recurrence in unmatched and matched analyses (hazard ratio for recurrent stroke: 0.11, 95% CI: 0.02-0.46; hazard ratio for death: 0.24, 95% CI: 0.08-0.75). Conclusion: Statin pretreatment in patients with acute LAA appears to be associated with better early outcomes regarding neurologic improvement, disability, survival, and stroke recurrence., SCOPUS: ar.j, info:eu-repo/semantics/published

Introduction: Intravenous administration of tissue-type plasminogen activator (IV-tPA) remains the only approved therapy that may reverse neurological deficit in patients with acute ischemic stroke (AIS). During the past 20 years, accumulating real-word experience have provided additional information regarding its safety and efficacy in various clinical settings that were originally considered as contraindications for systemic thrombolysis.Areas covered: In this narrative review, we address the safety of intravenous thrombolysis (IVT) in specific conditions: dissection of the aortic arch of extracranial and intracranial arteries, concomitant presence of unruptured intracranial aneurysms, arteriovenous malformations and dural fistulas, co-existing brain tumors as well as in conditions mimicking AIS. The review systematically evaluates the safety of off-label use of IVT and summarizes data from case reports of uncommon complications of systemic thrombolysis administration in the setting of acute cerebral ischemia.Expert opinion: The present narrative review summarizing 20 years of clinical experience with IVT for AIS highlights that many of the current guidelines and protocols should be adjusted to accommodate recent data from registries and real-world experience underscoring the safety of IVT in numerous conditions of AIS that were originally considered as relative or absolute contraindications for administration of IV-tPA., SCOPUS: re.j, info:eu-repo/semantics/published

Introduction: Intravenous administration of tissue-type plasminogen activator (IV-tPA) remains the only approved therapy that may reverse neurological deficit in patients with acute ischemic stroke (AIS). During the past 20 years, accumulating real-word experience have provided additional information regarding its safety and efficacy in various clinical settings that were originally considered as contraindications for systemic thrombolysis.Areas covered: In this narrative review, we address the safety of intravenous thrombolysis (IVT) in specific conditions: dissection of the aortic arch of extracranial and intracranial arteries, concomitant presence of unruptured intracranial aneurysms, arteriovenous malformations and dural fistulas, co-existing brain tumors as well as in conditions mimicking AIS. The review systematically evaluates the safety of off-label use of IVT and summarizes data from case reports of uncommon complications of systemic thrombolysis administration in the setting of acute cerebral ischemia.Expert opinion: The present narrative review summarizing 20 years of clinical experience with IVT for AIS highlights that many of the current guidelines and protocols should be adjusted to accommodate recent data from registries and real-world experience underscoring the safety of IVT in numerous conditions of AIS that were originally considered as relative or absolute contraindications for administration of IV-tPA., SCOPUS: re.j, info:eu-repo/semantics/published

The safety and efficacy of intravenous thrombolysis (IVT) in dissection-related ischemic stroke (DRIS) has not been established. We sought to determine safety and recovery rates of IVT in DRIS using prospective, international, multicenter data and by conducting a comprehensive meta-analysis of reported case series. We analyzed consecutive DRIS patients treated with IVT according to national guidelines during a 5-year period at six tertiary-care stroke centers, and also conducted a comprehensive review and meta-analysis of all available case series reporting safety outcomes in DRIS treated with IVT according to PRISMA guidelines. A total of 39 DRIS patients (mean age 60 ± 18 years; 59 % men; median NIHSS 13 points, IQR 9–17) received IVT in our multicenter study. Symptomatic intracranial hemorrhage (sICH), in-hospital mortality, complete recanalization, favorable functional outcome (FFO; mRS-score of 0–1) and functional independence (FI; mRS-score of 0–2) were 0 % (adjusted Wald 95 % CI 0–8 %), 10 % (3–24 %), 55 % (40–70 %), 61 % (45–74 %) and 68 % (52–81 %). The pooled sICH and mortality rates in meta-analysis including 10 case series (234 IVT-DRIS patients) were 2 % (0–5 %) and 4 % (0–8 %). The pooled recanalization, FFO and FI rates were 45 % (26–67 %), 41 % (29–54 %) and 61 % (48–72 %), respectively. Substantial heterogeneity was only found for FFO (I2 = 61 %; p = 0.006). Subsequent meta-regression analysis identified baseline NIHSS and dissection in the posterior circulation as independent predictors of FFO (p < 0.05), accounting for FFO variance across different studies. Our prospective, international data coupled with comprehensive meta-analysis results underscore IVT safety in DRIS, while further independent validation is required in larger observational registries or RCTs., SCOPUS: ar.j, info:eu-repo/semantics/published

In the Arctic, global warming is particularly pronounced so that we need to monitor its development continuously. On the other hand, the vast and hostile conditions make in situ observation difficult, so that available satellite observations should be exploited in the best possible way to extract geophysical information. Here, we give a resume of the sea ice remote sensing efforts of the European Union's (EU) project DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies). In order to better understand the seasonal variation of the microwave emission of sea ice observed from space, the monthly variations of the microwave emissivity of first-year and multi-year sea ice have been derived for the frequencies of the microwave imagers like AMSR-E (Advanced Microwave Scanning Radiometer on EOS) and sounding frequencies of AMSU (Advanced Microwave Sounding Unit), and have been used to develop an optimal estimation method to retrieve sea ice and atmospheric parameters simultaneously. In addition, a sea ice microwave emissivity model has been used together with a thermodynamic model to establish relations between the emissivities from 6 GHz to 50 GHz. At the latter frequency, the emissivity is needed for assimilation into atmospheric circulation models, but is more difficult to observe directly. The size of the snow grains on top of the sea ice influences both its albedo and the microwave emission. A method to determine the effective size of the snow grains from observations in the visible range (MODIS) is developed and demonstrated in an application on the Ross ice shelf. The bidirectional reflectivity distribution function (BRDF) of snow, which is an essential input parameter to the retrieval, has been measured in situ on Svalbard during the DAMOCLES campaign, and a BRDF model assuming aspherical particles is developed. Sea ice drift and deformation is derived from satellite observations with the scatterometer ASCAT (62.5 km gri

In the Arctic, global warming is particularly pronounced so that we need to monitor its development continuously. On the other hand, the vast and hostile conditions make in situ observation difficult, so that available satellite observations should be exploited in the best possible way to extract geophysical information. Here, we give a resume of the sea ice remote sensing efforts of the European Union's (EU) project DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies). In order to better understand the seasonal variation of the microwave emission of sea ice observed from space, the monthly variations of the microwave emissivity of first-year and multi-year sea ice have been derived for the frequencies of the microwave imagers like AMSR-E (Advanced Microwave Scanning Radiometer on EOS) and sounding frequencies of AMSU (Advanced Microwave Sounding Unit), and have been used to develop an optimal estimation method to retrieve sea ice and atmospheric parameters simultaneously. In addition, a sea ice microwave emissivity model has been used together with a thermodynamic model to establish relations between the emissivities from 6 GHz to 50 GHz. At the latter frequency, the emissivity is needed for assimilation into atmospheric circulation models, but is more difficult to observe directly. The size of the snow grains on top of the sea ice influences both its albedo and the microwave emission. A method to determine the effective size of the snow grains from observations in the visible range (MODIS) is developed and demonstrated in an application on the Ross ice shelf. The bidirectional reflectivity distribution function (BRDF) of snow, which is an essential input parameter to the retrieval, has been measured in situ on Svalbard during the DAMOCLES campaign, and a BRDF model assuming aspherical particles is developed. Sea ice drift and deformation is derived from satellite observations with the scatterometer ASCAT (62.5 km gri

In the Arctic, global warming is particularly pronounced so that we need to monitor its development continuously. On the other hand, the vast and hostile conditions make in situ observation difficult, so that available satellite observations should be exploited in the best possible way to extract geophysical information. Here, we give a resume of the sea ice remote sensing efforts of the European Union's (EU) project DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies). In order to better understand the seasonal variation of the microwave emission of sea ice observed from space, the monthly variations of the microwave emissivity of first-year and multi-year sea ice have been derived for the frequencies of the microwave imagers like AMSR-E (Advanced Microwave Scanning Radiometer on EOS) and sounding frequencies of AMSU (Advanced Microwave Sounding Unit), and have been used to develop an optimal estimation method to retrieve sea ice and atmospheric parameters simultaneously. In addition, a sea ice microwave emissivity model has been used together with a thermodynamic model to establish relations between the emissivities from 6 GHz to 50 GHz. At the latter frequency, the emissivity is needed for assimilation into atmospheric circulation models, but is more difficult to observe directly. The size of the snow grains on top of the sea ice influences both its albedo and the microwave emission. A method to determine the effective size of the snow grains from observations in the visible range (MODIS) is developed and demonstrated in an application on the Ross ice shelf. The bidirectional reflectivity distribution function (BRDF) of snow, which is an essential input parameter to the retrieval, has been measured in situ on Svalbard during the DAMOCLES campaign, and a BRDF model assuming aspherical particles is developed. Sea ice drift and deformation is derived from satellite observations with the scatterometer ASCAT (62.5 km gri

Grid computing has the potential to revolutionise how small groups of simulation scientists work together to tackle new science problems. In this paper we report how the eMinerals project has developed a small scale integrated compute and data grid infrastructure - the eMinerals minigrid - and developed generic job submission tools that exploit this infrastructure and which enable the science users to also access other grid systems.

This paper compares the relevance of various scaling for the stability study of the Rayleigh-Bénard-Marangoni extended problem when a ferrofluid layer is submitted to a weak magnetic field normal to it. Some preliminary results are reported. © 2004 Elsevier B.V. All rights reserved., SCOPUS: cp.j, info:eu-repo/semantics/published

This note introduces the linear stability of a ferrofluid thick layer submitted to gravity and to a normal magnetic field. The compatibility condition is derived taking into account the Rayleigh-Taylor instability and the Marangoni one. The pure normal deformation is analytically solved and these results can be extended to explain the heat conducting case. © Copyright 2005 Walter de Gruyter., SCOPUS: cp.j, info:eu-repo/semantics/published

info:eu-repo/semantics/published

This paper compares the relevance of various scaling for the stability study of the Rayleigh-Bénard-Marangoni extended problem when a ferrofluid layer is submitted to a weak magnetic field normal to it. Some preliminary results are reported. © 2004 Elsevier B.V. All rights reserved., SCOPUS: cp.j, info:eu-repo/semantics/published

This note introduces the linear stability of a ferrofluid thick layer submitted to gravity and to a normal magnetic field. The compatibility condition is derived taking into account the Rayleigh-Taylor instability and the Marangoni one. The pure normal deformation is analytically solved and these results can be extended to explain the heat conducting case. © Copyright 2005 Walter de Gruyter., SCOPUS: cp.j, info:eu-repo/semantics/published

info:eu-repo/semantics/published

The problem of solving System of Linear Algebraic Equations (SLAE) by parallel Monte Carlo numerical methods is considered. Three Monte Carlo algorithms are presented. In case when copy of the matrix is sent to each processor the execution time for solving SLAE by Monte Carlo on p processors is bounded by O(nNT/p) (excluding the initial loading of the data) where N is the number of chains and T is the length of the chain in the stochastic process, which are independent of matrix size n. Numerical tests are performed for a number of dense and sparse test matrices using PVM on a cluster of workstations.

Based on remote-sensing data and an expedition during August-September 1993, the importance of the Laptev Sea as a source area for sediment-laden sea ice was studied. Ice-core analysis demonstrated the importance of dynamic ice-growth mechanisms as compared to the multi-year cover of the Arctic Basin. Ice-rafted sediment (IRS) was mostly associated with congealed frazil ice, although evidence for other entrainment mechanisms (anchor ice, entrainment into freshwater ice) was also found. Concentrations of suspended particulate matter (SPM) in patches of dirty ice averaged at 156 g m(-3) (standard deviation sigma = 140 g m(-3)), with a background concentration of 5 g m(-3). The potential for sediment entrainment over the broad, shallow Laptev Sea shelf during fall freeze-up was studied through analysis of remote-sensing data and weather-station records for the period 1979-1994. Freeze-up commences on 26 September (sigma = 7 d) and is completed after 19 days (sigma = 6 d). Meteorological conditions as well as ice extent prior to and during freeze-up vary considerably, the open-water area ranging between 107 x 10(3) and 447 x 10(3) km(2). Ice motion and transport of IRS were derived from satellite imagery and drifting buoys for the period during and after the expedition (mean ice velocities of 0.04 and 0.05 m s(-1), respectively). With a best-estimate sediment load of 16 t km(-2) (ranging between 9 and 46 t km(-2)), sediment export from the eastern Laptev Sea amounts to 4 x 10(6) t yr(-1), with extremes of 2 x 10(6) and 11 x 10(6) t yr(-1). Implications for the sediment budget of the Laptev shelf, in particular with respect to riverine input of SPM, which may be of the same order of magnitude, are discussed.

Based on remote-sensing data and an expedition during August-September 1993, the importance of the Laptev Sea as a source area for sediment-laden sea ice was studied. Ice-core analysis demonstrated the importance of dynamic ice-growth mechanisms as compared to the multi-year cover of the Arctic Basin. Ice-rafted sediment (IRS) was mostly associated with congealed frazil ice, although evidence for other entrainment mechanisms (anchor ice, entrainment into freshwater ice) was also found. Concentrations of suspended particulate matter (SPM) in patches of dirty ice averaged at 156 g m(-3) (standard deviation sigma = 140 g m(-3)), with a background concentration of 5 g m(-3). The potential for sediment entrainment over the broad, shallow Laptev Sea shelf during fall freeze-up was studied through analysis of remote-sensing data and weather-station records for the period 1979-1994. Freeze-up commences on 26 September (sigma = 7 d) and is completed after 19 days (sigma = 6 d). Meteorological conditions as well as ice extent prior to and during freeze-up vary considerably, the open-water area ranging between 107 x 10(3) and 447 x 10(3) km(2). Ice motion and transport of IRS were derived from satellite imagery and drifting buoys for the period during and after the expedition (mean ice velocities of 0.04 and 0.05 m s(-1), respectively). With a best-estimate sediment load of 16 t km(-2) (ranging between 9 and 46 t km(-2)), sediment export from the eastern Laptev Sea amounts to 4 x 10(6) t yr(-1), with extremes of 2 x 10(6) and 11 x 10(6) t yr(-1). Implications for the sediment budget of the Laptev shelf, in particular with respect to riverine input of SPM, which may be of the same order of magnitude, are discussed.

Contains fulltext : 29348.pdf (preprint version ) (Open Access)

Contains fulltext : 29348.pdf (preprint version ) (Open Access)

Contains fulltext : 29348.pdf (preprint version ) (Open Access)