Assessing the effect of COVID 19 lockdowns on the composition of organic compounds and potential source of PM2.5 in Hanoi, Vietnam.

The ambient air quality during COVID-19 lockdowns has been improved in many cities in the world. This study is to assess the changes in persistent organic pollutants in PM2.5 during the COVID-19 lockdown in Hanoi. Individual organic species in PM2.5 ((e.g., polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs), and organochlorine pesticides (OCPs)) were measured in an urban residential area in Hanoi from before the March 10th to April 22nd, 2020, including before the partial lockdown (BL) and the partial lockdown (PL) phases. During the PL phase, the concentration of Σ14PAHs and Σ28PCBs was reduced by 38 and 52% compared with the BL period, respectively. The diagnostic ratio method implied that the sources of PAHs within the PL phase had a less effect on traffic and industrial activities than in the BL phase. The characteristic ratio method indicated that PCBs were mixed by commercial product and combustion process in both the BL and the PL periods, however, the source of PCBs in the BL phase was influenced by municipal waste incineration more than those in the PL phase. The decreasing concentration of Σ20OCPs during the partial lockdown was attributed to the restriction of human activities during the quarantine period. The results suggested that the source of OCPs was probably derived from the usage of pesticides in current and, historical degradation or the transportation of pesticides from the soil to the atmosphere.

Metal contamination, their ecological risk, and relationship with other variables in surface sediments of urban rivers in a big city in Asia: case study of Hanoi, Vietnam.

Urban rivers are significantly impacted by anthropogenic pressure. This study presents the updated assessment of the concentrations of 11 metals and other variables (pH, total organic carbon (TOC) and nutrients (total nitrogen, total phosphorus, and total silica)) in the sediments of four urban rivers in inner Hanoi city, Vietnam, during the period 2020-2022. The mean concentrations of Fe, Zn, As, and Cr were higher than the permissible values of the Vietnam National technical regulation on the surface sediment quality. Moreover, Zn and Cr were at the severe effect level of the US EPA guidelines for sediment quality. The calculation of pollution indices (Igeo and EF) demonstrated that Mn, Ni, and Fe were from natural sources whereas other metals were from both anthropogenic and natural sources. The ecological risk index revealed that metals in Hanoi riverine sediments were classified at considerable ecological risk. High values of metals, TOC, and nutrients in the sediments of these urban rivers mostly originate from the accumulation of untreated urban wastewater that is enhanced by low river discharge. Our results may provide scientific base for better management decisions to ensure environmental protection and sustainable development of Hanoi city.

Varietal and trait preferences for boiled sweetpotato in urban Hanoi and implications for breeding.

Cognizant of the need to refocus breeding efforts toward end-product quality traits taking into account the preferences of consumers and in consideration of the rapid urbanization in South-eastern Asia, this study investigated the consumer's preferences for sweetpotato in Hanoi. Using a mixed-methods research design, the study identified the most preferred and least preferred attributes of both the fresh and boiled product, disaggregated by gender, age, and socioeconomic status. Preferences and associated traits of six popular varieties were determined. Results indicate that while these varieties largely already meet consumers' preferences, consumers have a clear preference for a few varieties for which marginal adjustments are needed to further increase their acceptability among the growing urban population. Our findings indicate the direction of these adjustments and can contribute to inform demand-led national and international breeding programs and, ultimately, to higher and faster variety uptake and adoption.

Antimicrobial Resistance Patterns of Staphylococcus Aureus Isolated at a General Hospital in Vietnam Between 2014 and 2021.

Purpose: Staphylococcus aureus is a commensal bacteria species that can cause various illnesses, from mild skin infections to severe diseases, such as bacteremia. The distribution and antimicrobial resistance (AMR) pattern of S. aureus varies by population, time, geographic location, and hospital wards. In this study, we elucidated the epidemiology and AMR patterns of S. aureus isolated from a general hospital in Vietnam. Methods: This was a cross-sectional study. Data on all S. aureus infections from 2014 to 2021 were collected from the Microbiology department of Military Hospital 103, Vietnam. Only the first isolation from each kind of specimen from a particular patient was analyzed using the Cochran-Armitage and chi-square tests. Results: A total of 1130 individuals were diagnosed as S. aureus infection. Among them, 1087 strains were tested for AMR features. Most patients with S. aureus infection were in the age group of 41-65 years (39.82%). S. aureus isolates were predominant in the surgery wards, and pus specimens were the most common source of isolates (50.62%). S. aureus was most resistant to azithromycin (82.28%), erythromycin (82.82%), and clindamycin (82.32%) and least resistant to teicoplanin (0.0%), tigecycline (0.16%), quinupristin-dalfopristin (0.43%), linezolid (0.62%), and vancomycin (2.92%). Methicillin-resistant S. aureus (MRSA) and multidrug-resistant (MDR) S. aureus were prevalent, accounting for 73.02% and 60.90% of the total strains respectively, and the strains isolated from the intensive care unit (ICU) had the highest percentage of multidrug resistance (77.78%) among the wards. Conclusion: These findings highlight the urgent need for continuous AMR surveillance and updated treatment guidelines, particularly considering high resistance in MRSA, MDR strains, and ICU isolates. Future research focusing on specific resistant populations and potential intervention strategies is crucial to combat this rising threat.

Material and monetary flows of construction and demolition waste and assessment on physical and environmental properties of illegally dumped construction and demolition waste in Hanoi.

The main aim of this study is to investigate the material and monetary flows of CDW management and to characterize the distribution of illegally dumped CDW in Hanoi. Construction and demolition waste management has become a source of much concern to the urban authorities and citizens of big cities in Vietnam. It is estimated that 3000 t of CDW were generated per day from construction and demolition activities in Hanoi, but only 45% of the CDW was received at official landfills, while 55% of the CDW was disposed of elsewhere. The consequences of improper waste management are potentially alarming. The study conducted interviews to identify the material and cash flow associated with licensed and unlicensed contractors in CDW classification, transportation, treatment, and disposal, to characterize the distribution of illegally dumped CDW in two districts in Hanoi (urban and suburban districts), and to assess the composition of dumped CDW and environmental assessment of illegally dumped CDW by chemical analyses such as leaching and content tests. The study concluded that illegal dumping was performed mostly by unlicensed private companies. The illegally dumped CDW was mostly composed of mixed materials such as concrete, bricks, stones, and some hazardous materials such as asbestos and gypsum were found. The environmental concern of illegally dumped CDW was mostly dust, blockage of water ways, and inundation of increased suspended solids, whereas the heavy metal leaching concentration of all samples was below the environmental standards in Vietnam.

Molecular Characterization of Dengue Virus Strains from the 2019-2020 Epidemic in Hanoi, Vietnam.

Dengue virus (DENV), which has circulated in Vietnam for several decades, has multiple serotypes and genotypes. A 2019 dengue outbreak resulted in a larger number of cases than any other outbreak. We conducted a molecular characterization using samples collected in 2019-2020 from dengue patients in Hanoi and nearby cities located in northern Vietnam. The circulating serotypes were DENV-1 (25%, n = 22) and DENV-2 (73%, n = 64). Phylogenetic analyses revealed that all DENV-1 (n = 13) were genotype I and clustered to local strains circulating during the previous outbreak in the 2017, whereas DENV-2 consisted of two genotypes: Asian-I (n = 5), related to local strains from 2006-2022, and cosmopolitan (n = 18), the predominant genotype in this epidemic. The current cosmopolitan virus was identified as having an Asian-Pacific lineage. The virus was closely related to strains in other recent outbreaks in Southeast Asian countries and China. Multiple introductions occurred in 2016-2017, which were possibly from maritime Southeast Asia (Indonesia, Singapore, and Malaysia), mainland Southeast Asia (Cambodia and Thailand), or China, rather than from an expansion of localized Vietnamese cosmopolitan strains that were previously detected in the 2000s. We also analyzed the genetic relationship between Vietnam's cosmopolitan strain and recent global strains reported from Asia, Oceania, Africa, and South America. This analysis revealed that viruses of Asian-Pacific lineage are not restricted to Asia but have spread to Peru and Brazil in South America.

Assessing surface water pollution in Hanoi, Vietnam, using remote sensing and machine learning algorithms.

Rapid urbanization led to significant land-use changes and posed threats to surface water bodies worldwide, especially in the Global South. Hanoi, the capital city of Vietnam, has been facing chronic surface water pollution for more than a decade. Developing a methodology to better track and analyze pollutants using available technologies to manage the problem has been imperative. Advancement of machine learning and earth observation systems offers opportunities for tracking water quality indicators, especially the increasing pollutants in the surface water bodies. This study introduces machine learning with the cubist model (ML-CB), which combines optical and RADAR data, and a machine learning algorithm to estimate surface water pollutants including total suspended sediments (TSS), chemical oxygen demand (COD), and biological oxygen demand (BOD). The model was trained using optical (Sentinel-2A and Sentinel-1A) and RADAR satellite images. Results were compared with field survey data using regression models. Results show that the predictive estimates of pollutants based on ML-CB provide significant results. The study offers an alternative water quality monitoring method for managers and urban planners, which could be instrumental in protecting and sustaining the use of surface water resources in Hanoi and other cities of the Global South.

Occurrence and ecological risk assessment of organophosphate esters in surface water from rivers and lakes in urban Hanoi, Vietnam.

In this study, an investigation on the pollution status, distribution, and ecological risk to the aquatic organisms of six organophosphate tri-esters (tri-OPEs) and two organophosphate tri-esters (di-OPEs) in surface water in urban Hanoi, Vietnam were conducted. In 37 surveyed water samples (6 rivers and 17 lakes), all eight targeted OPEs were discovered with a detection frequency (DF) of 41-100% and the concentration varied largely from below the method detection limit (

SARS-CoV-2 Infection in a Hippopotamus, Hanoi, Vietnam.

While investigating the death of a hippopotamus at a zoo in Hanoi, Vietnam, we isolated SARS-CoV-2 and sequenced the RNA-dependent RNA polymerase gene from different organs. Phylogenetic analysis showed that the SARS-CoV-2 strain was closely related to 3 human SARS-CoV-2 strains in Vietnam.

Why are Hanoi students giving up on bus ridership?

University students are regarded as a readily available market segment for public transport. In Hanoi, as elsewhere, they constitute a large portion of bus passengers. However, one portion has been quitting buses, and the reasons were so far unknown. Nor was it clear whether they planned on retuning. Through a survey of more than 800 students in seven higher education institutions, this study aimed to find the answers to these questions. The study revealed that bus ridership was determined by socio-demographic variables (year of studies, household income, employment status, motorcycle ownership), environmental variables (home-university distance), and psychological variables (convenience, bus staff behaviour, risk of sexual harassment, reliability and health, image and status). A negative disruptor such as the fear of Covid-19 infection had little effect on the decision to continue riding buses. Meanwhile, the prospect of riding 'clean and green' electric buses, which were introduced in a pilot program, was a positive disruptor that may lead a portion of students to return to public transport.

Creative hubs in Hanoi, Vietnam: Transgressive spaces in a socialist state?

Vietnam's capital city has recently witnessed the emergence of a new type of cultural space akin to what have been labelled creative hubs in other contexts: that is, locales that foster creation, collaboration, community engagement and business development in the cultural sector. During the 2010s, Hanoi saw a proliferation of small-scale, art-oriented creative hubs, most of them community-led and developed without state funding. In a context marked by a government historically wary of contemporary and experimental arts, these spaces face various forms of state control ranging from the censorship of events, to stiff fines or even closure. Despite these barriers, creative hubs have become important sites for the gathering and formation of Hanoi's contemporary arts scene and countercultures. Based on over 80 interviews conducted in 2019, this paper investigates the motives behind the rise of these spaces in Hanoi and the political engagement techniques their founders, operators and users employ to remain in operation. Drawing on the notion of 'informal life politics', we argue that creative hubs seek to provide spaces of (partial) autonomy from governmentality in Hanoi. We further find that artists, intellectuals and other creative individuals use these spaces to challenge state controls. They do so not by lobbying formal institutions for policy changes, but instead by enacting the more open and free socio-cultural milieu they seek, from the bottom up.

Brain Activity Associated with the Planning Process during the Long-Time Learning of the Tower of Hanoi (ToH) Task: A Pilot Study.

Planning and decision-making are critical managerial functions involving the brain's executive functions. However, little is known about the effect of cerebral activity during long-time learning while planning and decision-making. This study investigated the impact of planning and decision-making processes in long-time learning, focusing on a cerebral activity before and after learning. The methodology of this study involves the Tower of Hanoi (ToH) to investigate executive functions related to the learning process. Generally, ToH is used to measure baseline performance, learning rate, offline learning (following overnight retention), and transfer. However, this study performs experiments on long-time learning effects for ToH solving. The participants were involved in learning the task over seven weeks. Learning progress was evaluated based on improvement in performance and correlations with the learning curve. All participants showed a significant improvement in planning and decision-making over seven weeks of time duration. Brain activation results from fMRI showed a statistically significant decrease in the activation degree in the dorsolateral prefrontal cortex, parietal lobe, inferior frontal gyrus, and premotor cortex between before and after learning. Our pilot study showed that updating information and shifting issue rules were found in the frontal lobe. Through monitoring performance, we can describe the effect of long-time learning initiated at the frontal lobe and then convert it to a task execution function by analyzing the frontal lobe maps. This process can be observed by comparing the learning curve and the fMRI maps. It was also clear that the degree of activation tends to decrease with the number of tasks, such as through the mid-phase and the end-phase of training. The elucidation of this structure is closely related to decision-making in human behavior, where brain dynamics differ between "thinking and behavior" during complex thinking in the early stages of training and instantaneous "thinking and behavior" after sufficient training. Since this is related to human learning, elucidating these mechanisms will allow the construction of a brain function map model that can be used universally for all training tasks.

The Association Between Ambient Temperatures and Hospital Admissions Due to Respiratory Diseases in the Capital City of Vietnam.

This study aimed to examine the short-term effects of ambient temperature on hospital admissions due to respiratory diseases among Hanoi residents. We collected 34,653 hospital admissions for 365 days (November 1, 2017, to November 31, 2018) from two hospitals in Hanoi. A quasi-Poisson regression model with time series analysis was used to explore the temperature-health outcome relationship's overall pattern. The non-linear curve indicated the temperatures with the lowest risk range from 22 degrees (Celcius) to 25 degrees (Celcius). On average, cold temperatures showed a higher risk than hot temperatures across all genders and age groups. Hospital admissions risk was highest at 13 degrees (Celcius) (RR = 1.39; 95% CI = 1.26-1.54) for cold effects and at 33 degrees (Celcius) (RR = 1.21, 95% CI = 1.04-1.39) for the hot effects. Temporal pattern analysis showed that the most effect on respiratory diseases occurred at a lag of 0 days for hot effect and at a lag of 1 day for cold effect. The risk of changing temperature among women and people over 5 years old was higher than other groups. Our results suggest that the risk of respiratory admissions was greatest when the temperature was low. Public health prevention programs should be enhanced to improve public awareness about the health risks of temperature changes, especially respiratory diseases risked by low temperatures.

Association between executive functions and gross motor skills in overweight/obese and eutrophic preschoolers: cross-sectional study.

BACKGROUND: Preschool age (3-5 years old) is a crucial period for children to acquire gross motor skills and develop executive functions (EFs). However, the association between the qualitative gross motor skills and EFs remains unknown in preschoolers, especially among overweight and obese children. METHODS: This was a cross-sectional, exploratory, and quantitative study carried out on 49 preschool children, divided into two subgroups according to their body mass index (overweight/obese: 24; eutrophic [normal weight]: 25). The mean age was 4.59 years. More than half of the sample were boys (55%) and most of the mothers had completed high school (67%) and were class C socioeconomic level (63%). Gross motor skills were assessed using the Test of Gross Motor Development-2, while EFs were evaluated using Semantic verbal fluency (SVF), Tower of Hanoi (TH), Day/Night Stroop, and Delayed Gratification tests. Multiple linear regression models adjusted for sex, age, maternal education, socioeconomic status, quality of the home environment, and quality of the school environment using the stepwise method were executed, considering the cognitive tasks as independent variables and gross motor skills as dependent variable. RESULTS: The overweight/obese preschoolers showed worse locomotor skills than their eutrophic peers and below average gross motor quotient (GMQ). Overweight/obese girls performed worse in OC skills than boys with excess weight. SVF (number of errors) and TH (rule breaks) explained 57.8% of the variance in object control (OC) skills and 40.5% of the variance in GMQ (p < .05) in the overweight/obese children. Surprisingly, there was no significant association between any of the EF tasks and gross motor skills in the eutrophic children. CONCLUSION: A relationship between EF tasks (number of errors in SVF and rule breaks in TH) and gross motor skills (OC and GMQ) was demonstrated in the overweight/obese preschoolers, indicating that worse cognitive flexibility, working memory, planning, and problem solving are associated with worse gross motor skills in this population when compared to eutrophic children.

Zoonotic Flavivirus Exposure in Peri-Urban and Suburban Pig-Keeping in Hanoi, Vietnam, and the Knowledge and Preventive Practices of Pig Farmers.

Mosquito-borne diseases (MBDs), including those caused by flaviviruses, remain human health problems for developing and urbanizing economies. This cross-sectional study examined risks of flavivirus exposure through a survey regarding knowledge and practices of pig farmers, and serological analysis of pigs in peri-urban and suburban Hanoi city. A total of 636 pig sera from 179 pig farms in 4 districts, namely, Chuong My, Dan Phuong, Ha Dong, and Bac Tu Liem, were analyzed by a competitive ELISA designed for flavivirus antibody detection. The results indicated a low level of awareness about MBDs among pig farmers, and a high seroprevalence in pigs at 88.5% (95%CI = 85.8-90.9%). Moreover, common practices of pig owners to prevent mosquitoes at home and farm did not show a significant reduction in flavivirus exposure in pigs. At animal level, significant associations between seropositive pigs and the farms with more than 60 pigs, and the district location were found. Farm-level multivariable analysis did not identify significant risk factors for flavivirus exposure. The study suggests that improving awareness of pig owners about MBDs in Hanoi city may be warranted to reduce the risk for MBD flavivirus infections in both humans and pigs.

The regulatory properties of anger under different goal orientations: the effects of normative and outcome goals.

BACKGROUND: The present study aimed to evaluate the self-regulatory properties of anger on the performance of individuals under various motivational dispositions using an experimental design. METHODS: The participants were 99 university students who participated in response to extra credit. The performance of the participants was evaluated using the Tower of Hanoi task. Their anger was measured using a facial expression recognition system and arousal was assessed using a heart-rate monitoring device. Two motivational dispositions were assessed: performance goals with normative evaluative standards and performance goals with a focus on outcomes. RESULTS: The results indicated that a nonlinear function explained the relationship between anger, arousal, and achievement under different goal conditions. Specifically, the Cusp Catastrophe Model showed that anger levels beyond a critical point were associated with the unpredictability of performance during the normative goal condition, suggesting that anger disturbed the relationship between arousal and achievement. Interestingly, a linear model was relevant for explaining the same relationships during the outcome goal condition. CONCLUSION: Thus, this study concluded that anger plays a more salient role when coupled with the pressures arising from employing interpersonal evaluative standards.

Impact of simulated acid rain on the growth of three species Brassica integrifolia, Brassica rapa, Brassica juncea in Hanoi, Vietnam.

Over the past decade, the extent and magnitude of acid rain in Vietnam and other Asian countries have become more apparent. In this study, the effect of simulated acid rain (pH 5.0, 4.0, and 3.0) and control treatment (pH 6.0) are observed for three species Brassica integrifolia, Brassica rapa, and Brassica juncea in Hanoi. The pot experiment was conducted for 42 days and arranged according to a randomized complete block design (RCBD), replicated 3 times with acid rain exposure being supplied every 4 days. The results show that acid rain causes direct damage to leaves. Observations reveal white spots on leaves; leaves getting discolored and gradually turning yellow, curling leaf marginals, and turning dark blue, with the most severe symptoms being necrotic leaves. Parameters of the shoot and root length, leaf area, biomass, and chlorophyll content all decrease as pH drops. However, the accumulation of proline content in leaves tends to increase with greater acidity. In conclusion, Brassica rara has the highest resistance capability to acid rain compared with Brassica integrifolia and Brassica juncea, especially its proline content is the highest at pH 3.0 in three Brassicaceae species.

The emergence of recreational cycling in Hanoi during the Covid-19 pandemic.

OBJECTIVES: This study examined recreational cycling in Hanoi, Vietnam, with a particular focus on changes brought about by the Covid-19 pandemic. The research questions were: (1) Has recreational cycling increased during the Covid-19 pandemic?; (2) If so, what factors have led to the increase?; and (3) What are some of the typical traits and behaviors of recreational cyclists? METHOD: Face-to-face surveys of 356 recreational cyclists were carried out in March-April 2021 in four areas of inner Hanoi. The survey data were modelled through two binary and one ordinal logit regression. RESULTS: Recreational cycling has become much more popular in Hanoi during the Covid-19 pandemic, with early morning being the preferred time for this activity (to avoid heavy traffic). A quarter of the participants had starting cycling recreationally since the first lockdown in April 2020, and about three quarters reported having noticed an increase in cycling activity around them. Nearly half of the participants cycled regularly (more than four times per week). The groups that were most likely to have taken up cycling for recreations during the pandemic included men, those living with children in the home, and those not working or studying. Age and income were not significant. People have been embracing cycling as a way to maintain or increase physical activity levels, and to safely socialize at the time when social gatherings are limited, walking is prohibited in some zones, and social distancing rules apply everywhere. CONCLUSION: To sustain the growth in recreational cycling and widen the time-window for this activity while ensuring everyone's safety, Hanoi's planning and public health sectors should join forces to adopt a combination of 'hard' and 'soft' measures. The authors recommend creating multi-use paths for micromobility modes, launching a public bikesharing scheme, regulating motorised modes, and social marketing that promotes recreational cycling as trendy.

Assessment of distributional characteristics and ecological risks of cyclic volatile methylsiloxanes in sediments from urban rivers in northern Vietnam.

In this report, four cVMSs including hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were determined in 85 sediment samples collected from three rivers in northern Vietnam during the period from May to November 2020. Total mean concentrations of cVMSs ranged from 75.4 to 15,000 ng/g-dw. The highest levels of cVMS were found in sediment samples collected from the To Lich River (range, 260-15,000 ng/g-dw; median, 2840 ng/g-dw), followed by the Nhue River (range, 188-6800 ng/g-dw; median, 1370 ng/g-dw), and the Day River (range, 75.4-4600 ng/g-dw; median, 666 ng/g-dw). Among cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest levels in all samples and ranged from 9.00 to 11,000 ng/g-dw. Significant correlations exist between the concentrations of D4/D6 and D5/D6 pairs in river sediment samples. Although the calculated ecological risk was not high, the presence of cVMSs in the sediment raises concerns about the impact on aquatic life because of their long-term accumulation capacity.

Large spatio-temporal variations of size-resolved particulate matter and volatile organic compounds in urban area with heavy traffic.

A monitoring campaign, the first of this kind for a heavy traffic urban area of Vietnam, was conducted which generated nearly 200 daily filter samples of PM2.5, PM10, and black carbon (BC), 1300 online hourly PMx (PM10, PM2.5, and PM1), 900 hourly/bi-hourly BTEX data, 700 h of traffic counts, and online meteorology records. PMx and BTEX levels show large horizontal gradients across this small urban area of 300 m width suggesting that the pollution data should be generated with sufficient spatial resolutions for assessment of the exposure and health effects. This paper focuses on analyzing PMx with reference to the previously published BTEX to provide a more complete picture of the traffic-related pollution in the area. Spatio-temporal variations of pollutants are analyzed in relation to traffic flows and fleet compositions, weekday-weekend effects, local and regional meteorology. PM10 and BTEX levels had larger variations between the sites indicating their stronger associations with the traffic activities than the finer particles. Twenty-four-hour (24 h) PM2.5 levels ranged between 19 and 191 µg/m3 with high PM1/PM2.5 ratios of above 0.8 at ambient site (AA) and above 0.7 at roadsides. Multivariate relationship analysis (PCA) for the bi-hourly datasets of meteorology, traffic flows, and pollutant levels indicated overwhelming influence of on-road traffic fleet compositions on the roadside pollutants levels. At AA, PCA results showed a complex interaction between local emissions, meteorological conditions, and regional/long-range transport. Higher pollution levels were associated with the airmass types having the continental origin and pathways.