Molecular Kondo effect in flat-band lattices

The Kondo effect of a single magnetic impurity embedded in the Lieb lattice is studied by the numerical renormalization group. When the band flatness is present in the local density of states, it quenches the participation of all dispersive electrons in the Kondo singlet formation, and reduces the many-body Kondo problem to a two-electron molecular Kondo problem. The two-electron analog of the many-body Kondo singlet, a quantum entanglement of two spins, is stable at low temperature, and the impurity contributions to thermodynamical and dynamical quantities are qualitatively different from that obtained in the conventional Kondo effect in systems without flat bands. The existence conditions of the molecular Kondo effect in narrow band systems are also discussed

APPLYING THE CASE METHOD IN TEACHING THE DEPARTMENT OF DEFENSE AND SECURITY EDUCATION AT THAI NGUYEN HIGH SCHOOL, VIETNAM

The case method is a teaching method based on real-life events that have happened or are happening. This method is based on constructivist theory and geared toward the target: education as preparation for solving life situations. Learning through solving situations helps students actively and strategically receive knowledge, flexibly apply knowledge and skills, and develop problem-solving abilities. By observing, interviewing, and experimenting, the article has developed a process of organizing case teaching and applied it in teaching National Defense and Security Education at Thai Nguyen High School, Vietnam. Initial results show that the percentage of students interested in the lesson is high (85%). That shows that the effectiveness of the method is feasible and creates a basis for continuing to use this teaching method in practice.  Article visualizations

ASSESSMENT OF THE POTENTIAL FOR DEVELOPMENT OF AGRITOURISM IN BINH DINH PROVINCE, VIETNAM

This study evaluates the potential for agritourism development in Binh Dinh Province, Central Vietnam. The analytical hierarchical process is used to determine the weights of four factors with 25 measurement criteria to assess agritourism potential. The research results show that Binh Dinh Province has great agritourism potential based on four evaluation factors, including (1) local agricultural tourism resources, (2) the trend for agritourism development and the agritourism market, (3) the local community’s willingness, and (4) the supporting activities of the local government. In particular, the local agricultural tourism resources factor received the highest score, followed by the local community’s willingness and the supporting activities of the local government. The trend for agritourism development and the agritourism market was rated the lowest. Therefore, Binh Dinh has viable opportunities to encourage the growth of agritourism to improve farmers’ livelihoodsDu lịch nông nghiệp đem lại nhiều cơ hội cho phát triển kinh tế cũng như đa dạng hóa các loại hình du lịch và cải thiện đời sống sinh kế của người dân. Nghiên cứu sử dụng phương pháp phân tích thứ bậc (AHP) để tính các trọng số của các tiêu chí đánh giá tiềm năng phát triển du lịch nông nghiệp tại các huyện, thị xã phía bắc tỉnh Bình Định. Tiếp theo, kết quả mô hình hóa sơ đồ mạng cho thấy cả 4 địa phương An Lão, Hoài Ân, Phù Mỹ, thị xã Hoài Nhơn đều được đánh giá ở mức điểm cao về tiềm năng phát triển du lịch nông nghiệp trên các khía cạnh tài nguyên du lịch, xu hướng phát triển du lịch, sự ủng hộ của người dân địa phương và sự quan tâm của chính quyền địa phương. Tuy nhiên, yếu tố xu hướng phát triển thị trường du lịch nông nghiệp được đánh giá ở mức điểm thấp hơn. Điều này cũng xuất phát từ việc phát triển du lịch nông nghiệp tại các huyện, thị xã phía Bắc tỉnh Bình Định cũng mới bắt đầu nhận được sự quan tâm trong vài năm gần đây, số lượt khách tham quan các huyện, thị xã phía Bắc tỉnh Bình Định còn ít so với tiềm năng du lịch của địa bàn

Musculoskeletal Pain and Work-related Risk Factors among Waste Collectors in Hanoi, Vietnam: A Cross-sectional Study

BACKGROUND: Musculoskeletal disorders (MSDs) are prevalent among waste collectors (WCs) in developing countries. AIM: This study aimed to investigate the prevalence of MSDs and the factors associated with the risk of persistent musculoskeletal pain among WCs in Hanoi, Vietnam. METHODS: A cross-sectional survey was utilized to study 468 WCs in 2017. The Örebro Musculoskeletal Pain Questionnaire and a questionnaire on demographic and work conditions were used to collect data. Descriptive and multivariate logistics regression analyzes were applied at a significance level of 0.05 to examine the factors related to the risk of persistent pain. FINDINGS: About 74.4% of the participants of this study experienced MSDs in at least one body region and 9.4% reported MSDs in all 10 body sites. The lower back was reported to be the most affected followed by the neck and shoulders. The risk of persistent musculoskeletal pain was significantly associated with age (odds ratio (OR) = 2.31, confidence interval (CI) = 1.05–5.09), gender (OR = 3.29, CI = 1.28–8.44), work hours (OR = 2.35, CI = 1.12–4.92), work shift (OR = 0.48, CI = 0.26–0.92), duration of poor postures of the neck (OR = 0.31, CI = 0.13–0.76), bent back (OR = 0.4 CI = 0.18–0.92) and for medial rotation (OR = 3.01, CI = 1.42–6.36), carrying heavy objects (OR = 2.94, CI = 1.15–7.48), and experience of work dissatisfaction (OR = 3.31, CI = 1.46-7.52), stress (OR = 7.14, CI = 3.14–16.24), or anxiety (OR = 6.37, CI = 3.07–13.21). CONCLUSIONS: High prevalence of MSDs among WCs and its association with self-assessed unfavorable work postures and work-related stress implies the need of mechanical and social support at work for WC to prevent the development of MSDs and persistent pain

Heat Stress Affects Seed Set and Grain Quality of Vietnamese Rice Cultivars during Heading and Grain Filling Period

Environmental stress trigger a variety of rice plant response, ranging from alters seed set, grain yield and grain quality during flowering and grain filling stage.  Efforts are required to improve our understanding of the impact of heat stress on rice production, which are essential strategies in rice cultivation. This article investigated the seed set, yield components and grain yield of Vietnamese rice cultivars (Indica germplasm) under high temperature environment during the flowering and grain filling stage. Six rice cultivars, including popular cultivars and new cultivars of Cuu Long Delta Rice Research Institute, and one popular extraneous cultivar with differences in maturing time, were grown in pots at high temperature (HT) and natural temperature condition as control (CT). All rice cultivars were subjected to the high temperature starting from the heading stage to the harvest maturity, applied by greenhouse effect. The greenhouse has about 25 cm window opening on 3 sides for air ventilation. The seed set rate of the heat-sensitive rice genotypes decreased significantly under HT, leading to a significant reduction in grain yield. The lowest seed set was recorded in “OM4900” (44.3%) and “OM18” (39.9%) under high temperature environment. The lower yield in all rice cultivars at an elevated temperature resulted in a dramatic decrease of filled grains and contributed to a loss of 1000-grain weight. ‘“OM892” is a potential rice cultivar for heat tolerant breeding program due to the seed set percentage was above 80% in both HT and CT conditions. High temperature during the grain filling stage resulted in a decreased amylose and increased chalkiness for all OM cultivars

The Age of Extreme

The COVID-19 pandemic caught the entire world off guard; presenting policy-makers with various thorny issues to address. This article probes the intersection of the COVID-19 pandemic and human rights. We argue that, on the one hand, there is a growing concern about excessive and disproportionate restrictions on human rights under the guise of ‘emergency powers’. On the other, the fact that rights are not taken seriously renders every effort to ward off the infectious disease faltering. Hence, we suggest that the COVID-19 pandemic should serve as a wake-up call for countries to step up their rights commitments. Despite the exceptional nature of the pandemic, human rights must remain at the heart of the States’ legal and policy choices

Study on the effect of processing methods on the total polyphenol, 2,3,5,4’-tetrahydroxystilben-2-O-β-D-glucoside, and physcion contents in Fallopia multiflora Thunb. Haraldson root

This study investigated the changes in the ingredients in Fallopia multiflora Thunb. Haraldson (FMT) root after processing it with different methods such as soaking, stewing, and steaming or combined methods. The total polyphenol, 2,3,5,4′-tetrahydroxystilben-2-O-β-D-glucoside (THSG), and physcion contents in FMT products after processing were determined using high-performance liquid chromatography (HPLC) and ultraviolet-visible (UV-VIS) methods. The results demonstrated that the processing method and time significantly affected the contents of polyphenol, THSG, and physcion. The physcion and total polyphenol content increased or decreased during processing depending upon the processing time, while the THSG content gradually decreased with an increase in the processing time. The content of physcion (a substance that can cause liver toxicity) was analysed, and the suitable conditions for processing of the FMT products were determined as initial soaking in rice swill for 24 h and subsequent stewing with black beans and water for 12 h

The Potential of Beauveria against Root Mealybugs Formiccoccus sp. (Homoptera: Pseudococidae) Black Pepper in Dak Lak Province of Vietnam

Root mealybugs Formicoccus sp.(Hemiptera: Pseudococcidae) currently emerge as an economically important soil-borne insect pest in the production of black pepper (Piper nigrum L.) in Dak Lak province of Vietnam. Entomopathogenic fungi can be used in agricultural production as feasible safe biocontrol agents and plant growth promoters. This study aimed to isolate, select and identify the local Beauveria sp. strains from the black pepper fields, as well as evaluate the effects of the selected strains on the growth of black pepper. The results showed that the frequency of positive Beauveria sp. soil samples collected from organic black pepper fields was significantly higher than that from conventional black pepper fields. Twenty-one Beauveria sp. strains in black pepper organic fields and four Beauveria sp. strains in black pepper conventional fields were successfully isolated, among them, the Beauveria bassiana BB1 was examined and evaluated for its biocontrol potential against Formicoccus sp. and its ability to promote the growth of black pepper seedlings. In the laboratory experiments, the mortality of both adults and first instar nymph root mealybugs Formicoccus sp. caused by B. bassiana BB1 culminated 100% at 21 days after treatments. In the nethouse, at 6 months after treatment, the efficacy of B. bassiana BB1 against black pepper root mealybugs reached 99.18%. The levels of photosynthetic pigments in the leaves of the black pepper seedlings increased about 2 times compared to the control. Moreover, B. bassiana BB1 strain also remarkably promoted the growth of the black pepper seedlings under the nethouse conditions