Environment Impacts and Composition - Biotoxic Activity in Natural Hydrocarbon Raw Materials & Processed Products

The paper aims to figure out What are environment impacts and composition - biotoxic activity in natural hydrocarbon raw materials and processed products. By using descriptive method for primary model, synthesis methods and process analysis and analysis of difficulties and discussion, The study of this problem point that, to assess the environmental impact of hydrocarbons on the biosphere, an accurate knowledge of the physical properties and chemical composition of oil and gas. Numerous tragic examples of accidents, such as those associated with a leak hydrogen sulfide gases. Hydrogen sulfide, due to its higher density relative to air settles in the lowlands of the relief, accumulating in calm weather in concentrations up to lethal. This leads to the death of animals and the death of people. The latter could be avoid by going to elevated windward areas, i.e., knowing the physical properties of this toxic gas

Impact of sea level rise on current and wave in Van Uc coastal area

This paper presents the results of analysis, comparison of some characteristics of current, wave at Van Uc estuary area when being affected by sea level rise due to climate change based on Delft3D model. Scenario groups are established: The current scenario and the scenarios simulating effect of sea level rise 0.5 m and 1.0 m. The results of calculation and simulation show that the velocity values change locally when sea level rises: Rise in the northern and southern areas (0.2–5 cm/s); decrease in the navigation channel (0.6–30 cm/s). Sea level rise causes the increase of wave height in the coastal area (13.5–43.8% in the dry season and 20–40% in the rainy season) and fewer changes in the outer area

Interpretation of 1H-NMR spectrum of alginate by 1H-1H TOCSY and COSY spectrum

The sodium alginate was prepared from brown seaweeds in Thua-Thien-Hue coastal area. The obtained alginate was characterized by 1H-NMR, 1H-1H TOCSY and COSY spectra. The  assignment of alginate peaks in 1H-NMR spectrum is 5.09, 4.446, 4.152, 4.318, 4.135 ppm in correspondence to H1, H2, H3, H4, H5 of D-mannuronic acid and 5.473, 4.318, 4.446, 4.571, 4.883 ppm in correspondence to H1, H2, H3, H4, H5 of L-guluronic acid, respectively. The present results are essential for the investigating guidance of alginate and its derivatives

A Giant Frontal Meningioma with Psychiatric Symptoms in a Young Woman: A Case Report

Background:Frontal meningioma is often asymptomatic but patients might experience psychiatric symptoms. Since symptoms are atypical in giant meningioma, to the best of our knowledge, we present a rare clinical scenario. Case Presentation: A 24-year old female patient with no medical history presented with two months of depressive symptoms, personality changes such as easy irritability, and feelings of frustration and mental depression, as well as forgetfulness and blurred vision. Brain magnetic resonance imaging (MRI) revealed a well-defined markedly enhancing lesion in the left frontal region measuring 65 x 70 x 70 mm with mass effects to the adjacent brain tissue and associated surrounding edema which was pressed to the frontal horn of the lateral ventricle. The patient underwent frontal unilateral craniotomy and excision of the tumor. After surgery, the quality of life was improved. Conclusion: Meningioma with psychiatric symptoms is quite rare. This clinical case helps clinicians avoid missing symptoms and use appropriate management strategies for patients with giant meningiomas

MÔ PHỎNG ẢNH HƯỞNG CỦA MỰC NƯỚC BIỂN DÂNG ĐẾN BIẾN ĐỘNG ĐỊA HÌNH ĐÁY VÙNG VEN BỜ CỬA SÔNG MÊ KÔNG

This paper presents some study results on morphological change in the coastal region of Mekong River under the influences of sea level rise. In order to set up the models, measured data were collected, systematically and homogeneously processed to create open boundary conditions (time-serial data) for the model. Open sea boundary conditions of the model were created by NESTING method. The model (Delft3D model) was set up with 4 layers in Sigma coordinate. The results of model were validated, showing a fairly good agreement with measured data (water elevation, currents, and suspended sediment concentration) at some places in the study area. Results of some scenarios of simulation (dry and flood season) show the sea level rise due to climate change could make a reduction in the seaward sediment transport and increase its settling around estuaries. As a result, sea level rise causes an increase in the accreted rate of sandbars in southern estuary of Mekong river coastal area. The influences of sea level rise on Mekong river coastal bed topography are prevailing in the region of about 7 - 10 km seawards. Further 10 km from the coast, influences of sea level rise on coastal morphology are not significant.Bài báo trình bày các kết quả nghiên cứu dự báo biến động địa hình ở vùng ven bờ châu thổ sông Mê Kông dưới ảnh hưởng của nước biển dâng. Để thiết lập mô hình tính, các chuỗi số liệu quan trắc đã được thu thập, xử lý hệ thống và đồng bộ cho các điều kiện biên (sông, biển) của mô hình dạng chuỗi số liệu (time serial data). Các biên mở phía biển của mô hình được tạo ra bằng phương pháp lưới lồng (NESTING) từ mô hình có miền tính rộng hơn ở phía ngoài. Mô hình Delft3D với 4 lớp độ sâu theo hệ tọa độ Sigma đã được thiết lập và kiểm chứng cho thấy có sự phù hợp với số liệu đo đạc. Kết quả dự báo trong mùa cạn và mùa lũ đã cho thấy sự dâng cao mực nước biển do biến đổi khí hậu làm hạn chế sự phát tán của dòng trầm tích về phía biển và tập trung di chuyển quanh các cửa sông. Qua đó làm tăng tốc độ bồi tại các bãi bồi khu vực phía ngoài các cửa sông phía nam của vùng ven bờ châu thổ sông Mê Kông. Những ảnh hưởng do dâng cao mực nước biển đến địa hình đáy ven bờ châu thổ sông Mê Kông phổ biến diễn ra trong phạm vi khoảng 7 -       10 km từ cửa sông ra phía ngoài. Ở phía ngoài 10 km từ bờ ra, ảnh hưởng do dâng cao mực nước đến địa hình đáy hầu như không đáng kể

Human Resource Management Practices and Firm Outcomes: Evidence from Vietnam

Using a panel sample of manufacturing firms from small- and medium-sized enterprise surveys between 2009 and 2013, we estimate the causal effects on firm outcomes of human resource management practices at the firm level in Vietnam. Employing a fixed-effects framework for the estimation, we find that on average a firm that provides the training for new workers gains roughly 13.7%, 10% and 14.9% higher in output value per worker, value added per worker and gross profit per worker respectively than the counterpart. Moreover, an additional ten-day training duration for new employees on average leads to 4.1% increase in output value per worker, 3.0% rise in value added per worker and 3.0% growth in gross profit per worker. We also uncover that a marginal 10% of HRM spending results in about 2% and 1.6% rises in output value per worker and value added per worker, respectively. Nevertheless, we find no statistically significant impacts of incentive measure on firm outcomes. The estimated results are strongly robust to various specifications

Human Resource Management Practices and Firm Outcomes: Evidence from Vietnam

Using a panel sample of manufacturing firms from small- and medium-sized enterprise surveys between 2009 and 2013, we estimate the causal effects on firm outcomes of human resource management practices at the firm level in Vietnam. Employing a fixed-effects framework for the estimation, we find that on average a firm that provides the training for new workers gains roughly 13.7%, 10% and 14.9% higher in output value per worker, value added per worker and gross profit per worker respectively than the counterpart. Moreover, an additional ten-day training duration for new employees on average leads to 4.1% increase in output value per worker, 3.0% rise in value added per worker and 3.0% growth in gross profit per worker. We also uncover that a marginal 10% of HRM spending results in about 2% and 1.6% rises in output value per worker and value added per worker, respectively. Nevertheless, we find no statistically significant impacts of incentive measure on firm outcomes. The estimated results are strongly robust to various specifications

Self-supervised few-shot learning for real-time traffic sign classification

Although supervised approaches for traffic sign classification have demonstrated excellent performance, they are limited to classifying several traffic signs defined in the training dataset. This prevents them from being applied to different domains, i.e., different countries. Herein, we propose a self-supervised approach for few-shot learning-based traffic sign classification. A center-awareness similarity network is designed for the traffic sign problem and trained using an optical flow dataset. Unlike existing supervised traffic sign classification methods, the proposed method does not depend on traffic sign categories defined by the training dataset. It applies to any traffic signs from different countries. We construct a Korean traffic sign classification (KTSC) dataset, including 6000 traffic sign samples and 59 categories. We evaluate the proposed method with baseline methods using the KTSC, German traffic sign, and Belgian traffic sign classification datasets. Experimental results show that the proposed method extends the ability of existing supervised methods and can classify any traffic sign, regardless of region/country dependence. Furthermore, the proposed approach significantly outperforms baseline methods for patch similarity. This approach provides a flexible and robust solution for classifying traffic signs, allowing for accurate categorization of every traffic sign, regardless of regional or national differences

Impact of sand mining on sediment transport and morphological change of Hai Phong coastal area

The paper presents the results of simulating the impact of sand mining on sediment transport and morphological change in Hai Phong coastal area based on Delft3D model. Scenario groups are established: Present scenarios without sand mining and simulated scenarios of the present sand mining (assuming 30% sand compared to plan). The scenario groups are calculated in the dry and rainy seasons for main wind directions (NE, SE, SW) in the case of moderate wind and strong wind. The results show that sand mining reduces sediment flow alongshore (2–81%) and seawards (5–83%). Besides, the increase in depth causes morphological change in this area: Rising the deposition rate (5–10 mm/month) at the sand mining locations; decreasing accretion rate and increasing the erosion rate in the neighboring areas of sand mining location

Liver Involvement Associated with Dengue Infection in Adults in Vietnam

Globally, the number of adults hospitalized with dengue has increased markedly in recent years. It has been suggested that hepatic dysfunction is more significant in this group than among children. We describe the spectrum and evolution of disease manifestations among 644 adults with dengue who were prospectively recruited on admission to a major infectious disease hospital in southern Vietnam and compare them with a group of patients with similar illnesses not caused by dengue. Transaminase levels increased in virtually all dengue patients and correlated with other markers of disease severity. However, peak enzyme values usually occurred later than other complications. Clinically severe liver involvement was infrequent and idiosyncratic, but usually resulted in severe bleeding. Chronic co-infection with hepatitis B was associated with modestly but significantly increased levels of alanine aminotransferase, but did not otherwise impact the clinical picture