311 research outputs found

    Integral manifolds for semilinear evolution equations and admissibility of function spaces

    No full text
    We prove the existence of integral (stable, unstable, and center) manifolds for the solutions to a semilinear integral equation in the case where the evolution family (U(t, s)) t≥s has an exponential trichotomy on a half line or on the whole line, and the nonlinear forcing term f satisfies the φ-Lipschitz conditions, i.e., where φ(t) belongs to some classes of admissible function spaces. Our main method is based on the Lyapunov–Perron methods, rescaling procedures, and the techniques of using the admissibility of function spaces.Доведено iснування iнтегральних (стiйких, нестiйких, центральних) многовидiв для розв’язкiв напiвлiнiйного iнтегрального рiвняння у випадку, коли сiм’я еволюцiй (U(t,s))tleqs має експоненцiальну трихотомiю на пiвосi або на всiй осi, а нелiнiйний збурюючий член f задовольняє φ-лiпшицевi умови, тобто належить до деяких класiв допустимих просторiв функцiй. Наш основний метод базується на методах Ляпунова – Перрона, процедурах перемасштабування та технiцi застосування допустимостi просторiв функцiй

    ARSENIC REMOVAL FROM WATER BY CHEMICAL OXIDATION AND ADSORPTION ON IN-SITU FORMED FERRIC HYDROXIDE

    Full text link
    Joint Research on Environmental Science and Technology for the Eart

    Estimation and Correction for the Temperature Lag in Thermoluminescent Measurements for LiF: Mg, Cu, Na, Si Phosphor

    Get PDF
    In the current work the glow curves for LiF:Mg,Cu,Na,Si thermoluminescent material were measured at various heating rates in the range from 1 K/s to 30 K/s. In the thermoluminescent measurements a contact heating was used to heat the powder samples. The temperature lag between the heating element and the dosimeter was estimated and corrected by applying Kitis-Tuyn's method. Some kinetic parameters of the traps in LiF:Mg,Cu,Na,Si were evaluated using a variable-heating-rate method

    Collaboration Between Social Workers and Educational Forces in Schools: Advantages, Objectives, Content, and Form

    Get PDF
    Cooperation between social workers and educational forces in high schools is viewed as a two-way cooperative effort to assist learners needing intervention. Intervention, emergency support for teachers or students needing intervention or assistance; Organize events to promote student development, community integration, and assistance for teachers and parents in need. The evaluation criteria for the cooperation between social workers and educational forces are based on four coordination components. Includes four scales evaluating the advantages, objectives, contents, and form of cooperation between high school social work personnel and educational agencies. A review of the cooperation between social work personnel and educational forces in high schools is gaining interest, although no research has been conducted on this topic. According to research findings, coordination between social work personnel and educational forces in high schools has been formed, albeit to a low and inconsistent degree across activities. The institution must perfect the organizational structure of its operations, management, and social work divisions. Furthermore, when coordinating with educational forces, social work personnel must emphasize the benefits of cooperation with educational forces. In addition, social workers must be adaptable between forms and activities according to the conditions and nature of their work.Ho Chi Minh City University CS.2021.19.4

    Childhood Acute Poisoning at Haiphong Children\u27s Hospital: A 10-Year Retrospective Study

    Get PDF
    INTRODUCTION: Children are most often harmed by acute poisoning, which may cause disability or even death. This demonstrates the critical necessity for epidemiologic studies specific to each nation and area since they aid in developing plans for the prevention of acute poisoning. There are no data or outdated data on acute poisoning in children in Vietnam. This research would partly fill this existing gap and compare the trend with other places across the globe. METHODS: A retrospective study was conducted in the 10-year period from 2012 to 2021 in Haiphong Children\u27s Hospital, Vietnam. RESULTS: There were 771 children hospitalized due to acute poisoning. Children in the 1-5-year-old group accounted for the highest rate, at 506 (65.6%). The mean age was 4.5 ± 4.1 years old. The male-to-female ratio was 1.2/1. Nonpharmaceutical chemicals were the most common agent in 331 cases (42.9%), including cleaning products 63 (19.0%), rat poison 60 (18.1%), and petrol 42 (12.7%). Medications were the second most common agent in 290 cases (37.6%), mostly paracetamol 60 (20.7%) and sedatives 40 (13.8%). There were 633 (82.1%) children exposed to poisons unintentionally. CONCLUSION: Children between the ages of 1 and 5 are more likely to be exposed to harmful substances. The most common agents were nonpharmaceutical chemicals followed by pharmaceuticals. Most incidents were inadvertent. Finally, our research may provide insights that public health authorities might use to plan practical actions

    Bridging Cultures in Academia: The Role of Mindfulness in Enhancing Intercultural Communication and Social Capital among Scholars

    Get PDF
    Studies that comprehensively incorporate mindfulness therapies and the theory of intercultural communication into the investigation of social capital are lacking in the body of existing literature. This restricts our comprehension of how these important components interact and affect social relationships in academic communities as a whole. Therefore, the purpose of this study is to investigate how mindfulness practices affect cross-cultural communication and, in turn, build social capital in academic environments. A mixed method was adopted in the study. In the first stage, focused group interviews are employed in the first stage with seven groups of nine Australian alumni, for a total of 63 participants who have experience conducting research and teaching abroad or in multicultural settings. In the second stage, 149 alumni were surveyed, and Process Macro SPSS\u27s Hayes model was used to analyse the data. The results showed that those who practice mindfulness are more likely to approach cross-cultural encounters with a greater awareness of and respect for different points of view. According to the findings, mindfulness can be a potent instrument for boosting perception of the community, networking, trust and safety, scholarly participation, citizen power, life values and diverse perspectives among academics. Scholars who engage in mindfulness practices have the potential to cultivate closer ties within academic communities, which could result in joint research opportunities, information exchanges, and career assistance. This study might offer academics a fresh theoretical viewpoint that improves the conceptual frameworks for mindfulness practice for enhancing academic social capital via intercultural communication

    Effects of financial statements information on firms’ value: evidence from Vietnamese listed firms

    Get PDF
    The paper studies the effects of information reporting in financial statements on values of Vietnamese firms. The study uses panel data with 1,070 observations from 214 firms, which are listed in the stock market of Vietnam in the period from 2012 to 2016. Multiple regression results show that the growth, firm size, profitability, auditing quality and timelineness are positively related to firm values, whereas the capital structure, auditing explanation negatively affect that indicator. The paper also indicates the inconsistency in measuring firms’ value by different measures including EV, Tobin’s Q or share price. Moreover, the research results reflect that measuring firms’ value by EV is more appropriate. The results of empirical research are instructive for enterprises to improve the usefulness of information in financial statements, thereby enhancing enterprises’ values

    Unexpected cases in field diagnosis of African swine fever virus in Vietnam: The needs consideration when performing molecular diagnostic tests

    Get PDF
    Background: The first confirmed case of African swine fever (ASF) in Vietnam was reported officially in February 2019. To date, ASF virus (ASFV) have been detected in 63/63 provinces in Vietnam. Currently, real-time polymerase chain reaction (PCR) is considered to be a powerful tool for viral detection in field samples, including ASFV. However, some recent reports have suggested that mismatches in primer and probe binding regions may directly affect real-time PCR qualification, leading a false-negative result.Aim: This study aims to further examine a conflicting result obtained from two OIE recommended methods, conventional PCR and real-time PCR, for ASFV detection.Methods: Two ASF suspected pigs from different provinces in the north of Vietnam were selected for this study based on clinical signs and postmortem lesions. The different results obtained by OIE-recommended conventional PCR and real-time PCR were further analyzed by the Sanger sequencing method and virus isolation in combination with hemadsorption (HAD) test using porcine alveolar macrophages cells.Results: The results showed that when the primer sequence matched perfectly with the sequences of field isolates, a mutation in probe binding region was found, indicating that a single mismatch in the probe binding site may cause a false-negative result by real-time PCR in detecting ASFV in clinical samples in Vietnam. An agreement between conventional PCR, using PPA1/PPA2 primers and two golden standard methods, virus isolation in combination with HAD assay, and sequencing method was observed in this study.Conclusion: A single mismatch in the probe binding site caused a failse-negative result by realtime PCR method in field diagnosis of ASFV. The needs consideration when selecting the appropriate molecular diagnostic methods is based on the current databases of ASFV sequences,  particularly for epidemiological surveillance of ASF. Keywords: African swine fever, PCR, Pigs, Real-time PCR, Vietna

    Management and monitoring of air and water pollution by using GIS technology: Research article

    Get PDF
    The need for a green clean living environment is increasing today, with the boom of the socioeconomic development, educational level. However, the environmental pollution becomes an alerted global issue due to the large amount of wastes discharged making this need to be not easily met at the moment. Greenhouse gas emission mainly from energy, transport and agricultural land use is causing climate change because of their long atmospheric lifetime and trapping the heat in the atmosphere. Harmful effects and damages caused by environment pollution and climate change are unpredictable. It was reported that every year millions of people die because of fine particles when exposing to air pollution and other millions die from water-born diseases. Management and monitoring of air and water pollution by using GIS technology is an effective method. The measured data can be obtained continuously, quickly and accurately at stations in any regions even with complex terrain. This helps reduce the required number of employees, manage automatically and continuously a large number of data.Ngày nay nhu cầu về một môi trường sống xanh, sạch đang gia tăng, với sự bùng nổ của phát triển kinh tế - xã hội và trình độ dân trí. Tuy nhiên, ô nhiễm môi trường đang trở thành một vấn đề cảnh báo toàn cầu do số lượng lớn các chất thải được xả ra môi trường làm cho nhu cầu này không dễ dàng được đáp ứng tại thời điểm này. Phát thải khí nhà kính chủ yếu là từ sử dụng năng lượng, giao thông vận tải và đất nông nghiệp đang gây ra biến đổi khí hậu vì thời gian tồn tại của cúng dài và giữ nhiệt trong khí quyển. Các ảnh hưởng xấu và thiệt hại gây ra bởi ô nhiễm môi trường và biến đổi khí hậu là không thể đoán trước. Thông tin báo cáo chỉ ra rằng mỗi năm có hàng triệu người chết vì hít các hạt bụi mịn khi tiếp xúc với ô nhiễm không khí; và hàng triệu người khác chết vì bệnh do nước sinh ra. Quản lý và giám sát ô nhiễm không khí và nước bằng cách sử dụng công nghệ GIS là một phương pháp hiệu quả. Các dữ liệu đo có thể được lấy liên tục, nhanh chóng và chính xác tại các trạm ở bất kể khu vực nào, ngay cả nơi có địa hình phức tạp. Điều này giúp làm giảm số lượng lao động cần thiết, quản lý tự động và liên tục một số lượng lớn dữ liệu

    Estimating Water Content and Grain Size of Intertidal Flat Sediments Using Visible to Shortwave-Infrared Reflectance and Sentinel 2A Data: A Case Study of the Red River Delta, Vietnam

    Get PDF
    Sediment properties such as water content (WC) and grain size (GS) are essential to characterize the environmental conditions of tidal flats. This article aimed to develop appropriate models to estimate the WC and GS of surface sediments for an intertidal flat on the Red river delta (Vietnam) using Sentinel 2A (S2A) images. The spectral reflectance, WC, and GS of 96 sub-samples from 12 sediment samples collected on December 17, 2017 were measured to clarify their relationships. The WC was highly correlated with the reflectance ratio of two shortwave-infrared bands, R(2190)/R(1610) (R² = 0.93). The median GS (D₅₀) at 0%, 15%, and 20% of WC was significantly correlated with the reflectance ratio of the near-infrared band (842 nm) versus the visible-green band (560 nm) (R² > 0.78). Next, D₅₀ was estimated from a multivariate regression model using this band ratio, the visible-red band (665 nm), and WC. The accuracy of the models was verified by comparisons with WC and D₅₀ from 20 samples collected on March 12th 2019 (RMSE of both WC and D₅₀ 30%) in very fine sediments (silts), which is consistent with other intertidal flats with similar sediment types. This article was limited to fine sediment samples. Therefore, our next step is to incorporate coarse sediments into the models to provide more universal mapping of WC and sediment types
    corecore