Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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THE INFLUENCE OF DIGITALIZATION ON CO2 EMISSIONS IN DEVELOPING COUNTRIES: POLICY INSIGHTS FOR VIETNAM
No full textDigital technology has become an unstoppable progression in most countries due to its vital role in socio-economic progress. Meanwhile, humanity is grappling with severe weather events such as superstorms, floods, and rising sea levels caused by escalating CO2 emissions. Does digitalization influence CO2 emissions in developing countries? For the answer, this study employs three indicators of digital technology to examine its impact on CO2 emissions across 89 developing countries from 2010 to 2023, utilizing difference generalized method of moments Arellano-Bond estimators. The findings indicate that digitalization contributes to increased CO2 emissions. Furthermore, economic growth and infrastructure expansion drive emissions upward, whereas inflation lowers them. These insights offer policy recommendations for developing countries to regulate digitalization in a way that curbs CO2 emissions
FUTURE CONSEQUENCES AND HOUSEHOLD FOOD WASTE: EXTENDING THE THEORY OF PLANNED BEHAVIOR IN A VIETNAMESE CONTEXT
No full textThis study extends the theory of planned behavior (TPB) by incorporating time perspective, operationalized as a consideration of future consequences (CFC), to explain attitudes and intentions toward reducing household food waste (HFW). Distinguishing between CFC-future and CFC-immediate, the study explores their influence on attitudes toward food waste (attitude-FW) and intentions to reduce HFW (intention-RFW). A survey of 375 Vietnamese consumers across four regions of Vietnam (North, Central, South, and Central Highlands) reveals that attitude-FW, subjective norms, and perceived behavioral control positively influence intention-RFW. Notably, CFC-future enhances both attitude-FW and intention-RFW, whereas CFC-immediate has no significant impact on attitude-FW and intention-RFW. These findings underscore the importance of fostering future-oriented thinking to promote sustainable food behaviors. By integrating CFC as an extended construct, this study enhances the explanatory power of the TPB model and offers valuable insights for designing interventions to address HFW challenges in Vietnam and elsewhere
VĂN HÓA GIAO TIẾP CỦA NGƯỜI ÊĐÊ QUA TỪ XƯNG HÔ TRONG SỬ THI Y’KHING JU
No full textIn communication, the way of addressing shows the attitudes and affection of the speakers and reflects the positions, perceptions, social and cultural relationships, and language abilities of the individuals in the community. To clarify the characteristics of the Ede people’s communication culture, the article analyzes the communication characteristics of the Ede people through relationships, methods, and rituals of addressing in the Y’Khing Ju epic.Trong giao tiếp, lối xưng hô không chỉ thể hiện thái độ, tình cảm của các chủ thể trong giao tiếp mà còn thể hiện vị trí, nhận thức, mối quan hệ xã hội, văn hóa và khả năng ngôn ngữ của cá nhân, cộng đồng. Để góp phần làm rõ thêm đặc trưng văn hóa giao tiếp của người Êđê, bài viết phân tích đặc trưng giao tiếp của người Êđê qua các mối quan hệ, cách thức và các nghi thức xưng hô qua sử thi Y Khing Ju
SUPERVISOR LEADERSHIP STYLE AND ORGANIZATIONAL CITIZENSHIP BEHAVIOR IN THE HOSPITALITY INDUSTRY: THE MODERATING ROLE OF TRAIT GRATITUDE
Get PDFThe hospitality industry heavily relies on the performance of frontline employees, and organizational citizenship behavior (OCB) plays a crucial role in enhancing service quality and customer satisfaction. This study investigates the impact of supervisor transformational leadership and servant leadership on three dimensions of OCB among frontline employees in the hospitality industry in Da Nang, Vietnam. Additionally, the moderating role of trait gratitude is examined. A theoretical model grounded in social exchange theory, broaden-and-build theory, and experimental studies is developed and empirically tested using data collected from 346 frontline employees of 3-star (or higher) hotels in Da Nang. The findings reveal that both supervisor transformational leadership and servant leadership significantly impact organizational citizenship behavior toward the organization (OCBO) and toward customers (OCBC), with supervisor servant leadership exhibiting a stronger influence. However, the hypothesized relationships between supervisor transformational leadership, supervisor servant leadership, and organizational citizenship behavior toward individuals (OCBI) are found to be nonsignificant. Moreover, trait gratitude moderates the relationship between supervisor transformational leadership and OCBO, as well as the relationship between supervisor servant leadership and both OCBO and OCBC. This research contributes to the understanding the effect of leadership style on OCB dimensions in the hotel industry and highlights the role of personality traits, such as trait gratitude, in shaping OCB
THE EFFECTS OF FAMILISM ON FAMILY CAREGIVER BURDEN IN VIETNAM: THE MEDIATING ROLE OF SOCIAL SUPPORT
Get PDFThis study examines how familism influences caregiver burden through the mediating role of social support among family caregivers of older adults in Vietnam, where rapid population aging presents significant challenges, with life expectancy at 75 years but healthy life expectancy at only 67.5 years (World Health Organization, 2019). Using a quantitative approach, we employ structural equation modeling to analyze data from 201 family caregivers of adults aged 65 and older in Hanoi, Vietnam. The findings revealed that both dimensions of familism–familial obligation and interconnectedness–negatively correlate with caregiver burden and that this relationship is partially mediated by social support. Specifically, stronger familistic beliefs are associated with increased social support, which in turn reduces caregiver burden. This study makes a novel contribution by being the first to examine the complex dynamics between cultural values, social support, and caregiving outcomes in the context of Vietnam, a developing country. The study addresses the current gap in understanding how internal resources (cultural beliefs) and external resources (social support) collectively influence caregiving outcomes. The findings provide valuable insights for developing culturally sensitive interventions and policies by suggesting ways to strengthen family support systems and leverage the existing cultural emphasis on familism. Practical implications indicate that reducing caregiving burden can positively impact employment status and wages for workers in the labor market (Marinho et al., 2022; Skira, 2015). Future research should consider examining additional cultural determinants and assessing intervention effectiveness for enhancing social support within Vietnam’s rapidly aging society
PHOTOCATALYTIC DEGRADATION OF METRONIDAZOLE BY AND - NANOMATERIALS
Get PDFAntibiotic residues in aquaculture wastewater pose a significant environmental challenge, as conventional wastewater treatment plants are often ineffective in their removal. To overcome this challenge, this study developed TiO2 nanowires on nanotube arrays (TNWs/TNAs) and further enhanced them with Bi2Se2Te nanoparticle (NP) decoration for efficient photocatalytic degradation of metronidazole. The TNWs/TNAs were fabricated through anodization in an aqueous solution of NH4F/ethylene glycol, while Bi2Se2Te NPs were obtained via a plasma-assisted exfoliation technique and subsequently deposited onto the TNWs/TNAs. The photocatalytic efficiency of TNWs/TNAs and Bi2Se2Te-TNWs/TNAs was evaluated by monitoring the degradation of metronidazole under ultraviolet-visible (UV-Vis) illumination using the HPLC-PDA method. All TiO2 nanostructures exhibited the anatase phase and displayed a distinct morphology, characterized by nanowires extending from nanotube arrays. The decoration of Bi2Se2Te nanoparticles onto TNWs/TNAs was visualized through SEM imaging and further validated using EDS, UV-Vis absorption spectroscopy, and Raman spectroscopy analysis. Both TNWs/TNAs and Bi2Se2Te-TNWs/TNAs effectively and rapidly degraded metronidazole, achieving removal efficiencies of 71.8% and 83.0% after 20 minutes of UV-Vis irradiation (100 mW·cm⁻²), respectively. Furthermore, the reaction rate constant of Bi2Se2Te-TNWs/TNAs (85.4 × 10-3 min-1) was higher than that of TNWs/TNAs (60.7×10-3 min-1), which was primarily attributed to the localized surface plasmon resonance (LSPR) effect of Bi2Se2Te NPs and enhanced charge separation within the hybrid Bi2Se2Te-TNWs/TNAs system. These findings demonstrate that Bi2Se2Te-TNWs/TNAs exhibit superior photocatalytic performance for antibiotic degradation, offering a promising strategy for wastewater treatment
ANTIBIOTIC RESISTANCE OF ACINETOBACTER BAUMANNII AT CAN THO GENERAL HOSPITAL IN 2019–2023
Get PDFThis study examines antibiotic resistance patterns in Acinetobacter baumannii isolates from Can Tho General Hospital, Vietnam, between 2019 and 2023, focusing on multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) strains. The goal is to assess the prevalence of resistance and its clinical implications. Respiratory specimens from various departments, including the intensive care unit (ICU), were analyzed. Bacterial identification and antibiotic susceptibility testing were conducted using standard microbiological techniques and the Vitek-2 Compact system. Resistance patterns were categorized as MDR, XDR, and PDR, and extended-spectrum beta-lactamase (ESBL) production was evaluated. MDR, XDR, and PDR were prevalent in 11.0%, 73.2%, and 15.7% of A. baumannii isolates. Resistance rates fluctuated over the five-year period, with a significant rise in PDR in 2021. ESBL production was strongly associated with increased resistance to key antibiotics, including vancomycin, clindamycin, erythromycin, and gentamicin. Statistically significant differences (p < 0.001) were observed between the ESBL-producing and non-ESBL-producing strains, particularly for ciprofloxacin, levofloxacin, and gentamicin. The study underscores the increasing threat posed by MDR, XDR, and PDR A. baumannii strains, particularly those producing ESBL, which exhibit higher resistance to crucial antibiotics. These findings highlight the urgent need for continuous surveillance, antibiotic stewardship, and targeted interventions, especially in ICUs, to prevent the further spread of resistant strains and improve patient outcomes
REMARKS ON LIPSCHITZ GEOMETRY OF GLOBALLY CONIC SINGULAR MANIFOLDS
Get PDFWe study metric properties of manifolds with conic singularities and present a natural interplay between metrically conic and metrically asymptotically conic behavior. As a consequence, we prove that a singular sub-manifold is Lipschitz normally embedded (i.e., its inner and outer metric structures are equivalent) in an ambient singular manifold whenever the singularities are conic and the ends of the manifold are asymptotically conic, which answers positively a question of Costa et al. (2024c)
EXAMINING THE IMPACT OF CAPITAL EXPENDITURE ON CORPORATE CARBON EMISSION DISCLOSURE: THE ROLE OF ENVIRONMENTAL SYNERGY
Get PDFEmissions have become a major global concern as the urgency to address climate change intensifies, highlighting the need for transparent corporate carbon emission disclosures to inform stakeholders and promote corporate accountability in reducing greenhouse gas emissions. This study investigates the impact of capital expenditure on carbon emission disclosure across companies operating in 15 countries from 2009 to 2021. Furthermore, it explores how environmental synergy moderates the relationship between capital expenditure and carbon emission disclosure. Using a dataset comprising 1,202 firm-year observations, the study provides empirical evidence that capital expenditure has a significantly positive impact on the level of carbon emission disclosure in the full sample and in industries classified under the primary class. Interestingly, the effect is statistically insignificant for industries in the secondary and end-use activity classes. Notably, the relationship between capital investment and carbon emission disclosure is negative for the end-use activity class, with environmental synergy playing a strong moderating role. These findings offer valuable insights for investors and researchers by proposing a reliable approach to assess corporate carbon emission disclosures. Our findings also offer several important policy implications, all of which are relevant to the Vietnamese market
CAMELLIA PAUCIPUNCTATA (THEACEAE), A NEW RECORD FOR THE FLORA OF VIETNAM
Get PDFCamellia paucipunctata is described and illustrated as a new record for the flora of Vietnam. C. paucipunctata is a small tree with young branches glabrous; leaf blade elliptic to broadly elliptic or obovate, glabrous; secondary veins 6–7 pairs, obscurely serrulate, abaxially pale green and brown glandular punctate; flowers subsessile; sepals 4–(5), velutinous on the face; petals 5–6, broadly obovate, yellowish-white; stamens united at the base, inside velutinous; ovary 3–(4)-loculed; style 3–(4), free, 5–8 mm, glabrous; capsule subglobose to globose, 4.5–5.0 cm high, 3.0–4.0 cm wide, 3–(4)-loculed, pericarp thick, furfuraceous. The morphological evidence supports its placement in Camellia section Heterogenea