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1.
Article in English | MEDLINE | ID: mdl-38836968

ABSTRACT

Religiously inspired travel has burgeoned in Vietnam in recent years, amidst rapid economic development and a booming tourist industry. Buddhist pilgrimages particularly attract older women, who compose the majority of temple goers in Vietnam. Having lived through volatile historical periods of war, economic hardship, and political transformations, travelling on pilgrimage is the first opportunity for many older Vietnamese women to enjoy new places and experiences. Drawing on data collected during my field research among Buddhist women pilgrims in their sixties and seventies from Ho Chi Minh City, I show how pilgrimage is seen as a journey of a lifetime and how it reflects the perception of life and self-transformation along the life course. Drawing on Victor and Edith Turner's (1978 [2011]) discussion of pilgrimage as the antistructure of everyday social life, this paper explains why pilgrimage is markedly different from other life experiences of Vietnamese women, and how religious travel positions old age not as the culmination of self-development, but rather as an ongoing process of gaining wisdom.

2.
J Phys Condens Matter ; 36(26)2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38547530

ABSTRACT

We computed the phase diagram of zigzag graphene nanoribbons as a function of on-site repulsion, doping, and disorder strength. The topologically ordered phase undergoes topological phase transitions into crossover phases, which are new disordered phases with non-universal topological entanglement entropy that exhibits significant variance. We explored the nature of non-local correlations in both the topologically ordered and crossover phases. In the presence of localization effects, strong on-site repulsion and/or doping weaken non-local correlations between the opposite zigzag edges of the topologically ordered phase. In one of the crossover phases, bothe-/2solitonic fractional charges and spin-charge separation were absent; however, charge-transfer correlations between the zigzag edges were possible. Another crossover phase contains solitonice-/2fractional charges but lacks charge transfer correlations. We also observed properties of non-topological, strongly disordered, and strongly repulsive phases. Each phase on the phase diagram exhibits a different zigzag-edge structure. Additionally, we investigated the tunneling of solitonic fractional charges under an applied voltage between the zigzag edges of undoped topologically ordered zigzag ribbons, and found that it may lead to a zero-bias tunneling anomaly.

3.
Entropy (Basel) ; 25(10)2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37895570

ABSTRACT

Graphene zigzag nanoribbons, initially in a topologically ordered state, undergo a topological phase transition into crossover phases distinguished by quasi-topological order. We computed mutual information for both the topologically ordered phase and its crossover phases, revealing the following results: (i) In the topologically ordered phase, A-chirality carbon lines strongly entangle with B-chirality carbon lines on the opposite side of the zigzag ribbon. This entanglement persists but weakens in crossover phases. (ii) The upper zigzag edge entangles with non-edge lines of different chirality on the opposite side of the ribbon. (iii) Entanglement increases as more carbon lines are grouped together, regardless of the lines' chirality. No long-range entanglement was found in the symmetry-protected phase in the absence of disorder.

4.
Biochem Soc Trans ; 51(4): 1733-1745, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37610008

ABSTRACT

Physical properties of tissue are increasingly recognised as major regulatory cues affecting cell behaviours, particularly cell migration. While these properties of the extracellular matrix have been extensively discussed, the contribution from the cellular components that make up the tissue are still poorly appreciated. In this mini-review, we will discuss two major physical components: stiffness and topology with a stronger focus on cell-cell interactions and how these can impact cell migration.


Subject(s)
Cell Communication , Extracellular Matrix , Cytosol , Cell Movement , Virion
5.
Environ Sci Pollut Res Int ; 30(13): 36533-36544, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36562974

ABSTRACT

Air pollution is one of the most concerning environmental issues, wherein PM2.5 concentration plays an important role. This study monitored and evaluated the PM2.5 concentration trends in Bien Hoa City, Dong Nai Province, Vietnam. Twenty 24-h PM2.5 samples were continuously collected during the rainy (15 Oct. to 25 Oct. 2021) and dry (19 Mar. to 29 Mar. 2022) seasons. The PM2.5 samples were analyzed by scanning electron microscopy to determine the surface pattern and size distributions were analyzed using ImageJ software. The water-soluble fractions of 15 trace metal(oid)s concentrations (Al, Cu, Ni, K, Ca, Co, Mn, Cr, As, Zn, Pb, Cd, Na, Fe, and Mg) bound to PM2.5 were analyzed by inductively coupled plasma-mass spectrometry. The results showed that the 24-h fine fraction PM2.5 concentrations were 24.1 ± 12.2 µg/m3 and 63.0 ± 18.7 µg/m3 in the rainy and dry seasons, respectively. The results indicate that the size distributions of the particles of 2.0-2.5 µm are minor, and the majority are ultrafine particles with aerodynamic diameter ≤ 1.0 µm. Overall, the mass concentration level of the water-soluble fraction of trace metal(oid)s in PM2.5 in the rainy season was higher than that in the dry season. Among these, Ca, K, and Na were the most abundant earth crustal elements in PM2.5 in the rainy and dry seasons, accounting for 85% and 41.2% of the total trace element concentrations, respectively. The major sources of PM2.5 are local and regional sources of thermal power plants, industrial parks, and waterborne transportation (domestic rivers and marine). The activities undertaken to remove Agent Orange (e.g., soil excavation, transportation, and rotary kiln incinerators) at the Bien Hoa airbase area also cause increases in the PM2.5 level in the atmosphere of Bien Hoa City.


Subject(s)
Air Pollutants , Air Pollution , Trace Elements , Environmental Monitoring/methods , Vietnam , Particulate Matter/analysis , Air Pollution/analysis , Water/analysis , Seasons , Trace Elements/analysis , Ions/analysis , Air Pollutants/analysis
6.
Environ Pollut ; 318: 120927, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36565909

ABSTRACT

Volatile organic compounds (VOCs) play an important role in urban air pollution, both as primary pollutants and through their contribution to the formation of secondary pollutants, such as tropospheric ozone and secondary organic aerosols. In this study, more than 30 VOC species were continuously monitored in the two most populous cities in Vietnam, namely Ho Chi Minh City (HCMC, September-October 2018 and March 2019) and Hanoi (March 2019). In parallel with ambient VOC sampling, grab sampling was used to target the most prevalent regional-specific emission sources and estimate their emission factors (EFs). Emission ratios (ERs) obtained from ambient sampling were compared between Vietnamese cities and other cities across the globe. No significant differences were observed between HCMC and Hanoi, suggesting the presence of similar sources. Moreover, a good global agreement was obtained in the spatial comparison within a factor of 2, with greater ER for aromatics and pentanes obtained in the Vietnamese cities. The detailed analysis of sources included the evaluation of EF from passenger cars, buses, trucks, motorcycles, 3-wheeled motorcycles, waste burning, and coal-burning emissions. Our comparisons between ambient and near-source concentration profiles show that road transport sources are the main contributors to VOC concentrations in Vietnamese cities. VOC emissions were calculated from measured EF and consumption data available in Hanoi and compared with those estimated by a global emission inventory (EDGAR v4.3.2). The total VOC emissions from the road transport sector estimated by the inventory do not agree with those calculated from our observations which showed higher total emissions by a factor of 3. Furthermore, the inventory misrepresented the VOCs speciation, mainly for isoprene, monoterpenes, aromatics, and oxygenated compounds. Accounting for these differences in regional air quality models would lead to improved predictions of their impacts and help to prioritise pollution reduction strategies in the region.


Subject(s)
Air Pollutants , Environmental Pollutants , Ozone , Volatile Organic Compounds , Humans , Air Pollutants/analysis , Cities , Volatile Organic Compounds/analysis , Environmental Monitoring , Southeast Asian People , Vietnam , Ozone/analysis , Environmental Pollutants/analysis , China , Vehicle Emissions/analysis
7.
CNS Neurol Disord Drug Targets ; 21(7): 621-630, 2022.
Article in English | MEDLINE | ID: mdl-34414874

ABSTRACT

AIMS: To investigate the efficacy and safety of Cerebrolysin and Cerebrolysin plus nootropics in the routine treatment of patients with acute ischemic stroke (AIS). BACKGROUND: Acute ischemic stroke (AIS) is a leading cause of disability with unmet treatment needs lacking effective drug therapy. Multimodal drugs modulating stroke pathophysiology as Cerebrolysin constitute a good therapeutic option. OBJECTIVE: In this study, we assessed the effects of Cerebrolysin and Cerebrolysin plus nootropics, in comparison with other nootropic drugs alone, on functional, neurological and cognitive recovery of patients with AIS in Vietnam. METHODS: This non-interventional, controlled, open-label, prospective and multicenter study included 398 AIS patients (234 males) treated with Cerebrolysin (n=190; 20 i.v. infusions of 10 ml), other nootropics (comparator group; n=86), or a combination of both (n=122). The study primary endpoint was the modified Ranking Scale (mRS) score on day 90. Secondary endpoints included study-period change in NIHSS score; percentage of well-recovered (mRS 0-2) patients, the proportion of good NIHSS response (≥6 points) cases, and MoCA scores at day 90; and safety indicators. RESULTS: Compared with other nootropics, both Cerebrolysin and combined therapy induced significant improvements (p<0.001) in: Functional recovery (mRS scores); percentage of well-recovered patients (Cerebrolysin: 81.6%; combination: 93.4%; comparator: 43.0%); neurological recovery (study- period NIHSS change); proportion of good NIHSS responders (Cerebrolysin: 77.5%; combination: 92.5%; comparator: 47.6%); and MoCA scores (Cerebrolysin: 23.3±4.8; combination: 23.7±4.1; comparator: 15.9±7.7). Compared to Cerebrolysin, combined therapy improved (p<0.01) mRS outcomes and NIHSS change, but not MoCA scores, in moderate-severe stroke (NIHSS>11) cases only. No drug-related adverse events were reported. CONCLUSION: Cerebrolysin alone or combined with other nootropics was effective and safe in routine AIS treatment, during both acute and recovery phases, which supports its use in daily clinical practice. Others: According to the results of this multicenter study, the importance of reducing differences in the treatment regimens of AIS in Vietnam should be further emphasized.


Subject(s)
Brain Ischemia , Ischemic Stroke , Neuroprotective Agents , Nootropic Agents , Stroke , Amino Acids , Brain Ischemia/complications , Brain Ischemia/drug therapy , Female , Humans , Male , Neuroprotective Agents/therapeutic use , Nootropic Agents/therapeutic use , Pregnancy , Prospective Studies , Stroke/complications , Stroke/drug therapy , Treatment Outcome , Vietnam
8.
Sci Rep ; 11(1): 792, 2021 01 12.
Article in English | MEDLINE | ID: mdl-33436988

ABSTRACT

Biomass, one of the renewable resources, is expected to play an important role in the world's energy future. In Asia, rice straw is an abundant agricultural surplus because rice is one of the leading staple food crops in the region. Often, rice straw is burned directly in the field via uncontrolled combustion methods that emit large amounts of short-lived air pollutants, greenhouse gases, and other pollutants. In Vietnam, the energy and environment protection sectors are facing great challenges because of rapid urbanisation and industrialisation. A national strategic choice is to exploit renewable energy, including biomass-derived energy, to achieve energy security and CO2 emission reduction. This study investigates the potential of rice straw as an energy source for power plants at a local scale in Vietnam using data derived from satellite Sentinel-1 images. The results show that Vietnam can produce 2,565 MW from rice straw, for which 24 out of 63 provinces have a potential capacity higher than 30 MW, and the Kien Giang province has the highest capacity (245 MW). The study also analyses limitations and obstacles overcoming which can promote the biomass energy sector in the country.

9.
Environ Sci Pollut Res Int ; 28(10): 12067-12081, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32447726

ABSTRACT

The WRF-Chem (Weather Research and Forecasting with Chemistry) model is implemented and validated against ground-based observations for meteorological and atmospheric variables for the first time in Northern Vietnam. The WRF-Chem model was based on HTAPv2 emission inventory with MOZCART chemical-aerosol mechanism to simulate atmospheric variables for winter (January) and summer (July) of 2014. The model satisfactorily reproduces meteorological fields, such as temperature 2 m above the ground and relative humidity 2 m above the ground at 45 NCHMF meteorological stations in January, but lower agreement was found in those simulations of July. PM10 and PM2.5 concentrations in January showed good temporal and spatial agreements to observations recorded at three CEM air monitoring stations in Phutho, Quangninh, and Hanoi, with correlation coefficients of 0.36 and 0.59. However, WRF-Chem model was underestimated with MFBs from - 27.9 to - 118.7% for PM10 levels and from - 34.2 to - 115.1% for PM2.5 levels. It has difficulty in capturing day-by-day variation of PM10 and PM2.5 concentrations at each station in July, but MFBs were in the range from - 27.1 to - 40.2% which is slightly lower than those in January. It suggested that further improvements of the model and local emission data are needed to reduce uncertainties in modeling the distribution of atmospheric pollutants. Assessment of biomass burning emission on air quality in summer was analyzed to highlight the application aspect of the WRF-Chem model. The study may serve as a reference for future air quality modeling using WRF-Chem in Vietnam.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Environmental Monitoring , Particulate Matter/analysis , Vietnam
10.
Chemosphere ; 265: 129092, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33303230

ABSTRACT

There is growing concern regarding human dietary exposure to arsenic (As) via consumption of rice. The concentration and speciation of As in rice are highly variable, and models describing rice As speciation as a function of environmental covariates remain elusive. We conducted a survey of paddy rice and soil in the Mekong Delta with the objective of linking patterns in rice As content to soil chemical variables or hydrogeological parameters. The sum of As species (ΣAs) in husked rice averaged 243 µg/kg and the average inorganic As (iAs) content was 84%. There was no relationship found between rice As concentration or speciation and As levels in soil. However, mean As concentrations in groundwater near rice sampling locations were strongly correlated with grain ΣAs and iAs over a large part of the study region, despite the fact that groundwater is not commonly used for rice paddy irrigation in this region. We hypothesize that surficial sediments with high concentrations of soluble and plant-available As also serve as sources of arsenic to downgradient shallow aquifers, explaining the observed associations between rice and groundwater As. This study suggests that shallow groundwater As concentrations may serve as a useful indicator for locations at risk of elevated iAs concentrations in rice.


Subject(s)
Arsenic , Groundwater , Oryza , Soil Pollutants , Water Pollutants, Chemical , Arsenic/analysis , Food Contamination/analysis , Humans , Soil Pollutants/analysis , Water Pollutants, Chemical/analysis
11.
Glob Chang Biol ; 26(9): 4691-4721, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32531815

ABSTRACT

Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co-benefits with and trade-offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade-offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post-harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co-benefits and trade-offs of different policy approaches can help decision-makers choose the more effective, or at the very minimum, more benign interventions for implementation.


Subject(s)
Conservation of Natural Resources , Sustainable Development , Agriculture , Animals , Carbon , Goals , Humans , Soil , United Nations
12.
Environ Pollut ; 260: 113972, 2020 May.
Article in English | MEDLINE | ID: mdl-31962266

ABSTRACT

Although rice straw open burning is one of the main sources of air pollution in Asian countries, problems remain in collecting the activity data needed to calculate emission inventories. In Vietnam, the results from traditional data collection methods, which are reported by the Vietnam General Statistics Office high levels of uncertainty. This is largely due to a lack of human and financial resources. To improve upon this, this study critically assessed the benefits of incorporating cultivation area data obtained by the Sentinel-1 Synthetic Aperture Radar (SAR) satellite in combination with crop production records during the period of 2015-2017. The results suggested that incorporating remote sensing data, especially satellite data, into a process-based crop model can improve the spatial distribution of yield estimates. Satellite data for 2018 were also applied to estimate emissions from rice straw open burning in the Red River Delta, Vietnam, for which official statistics are not otherwise yet available. The results show that a total of 3.24 Mt of burnt rice straw produced 3.82 Mt of CO2, 301 Gg of CO, 29.5 Gg of PM10, and 27 Gg of PM2.5. The estimated emission amounts for the common air pollutants SO2, NOx, and NH3 were 583 tonnes, 7.4 Gg, and 13.3 Gg, respectively. Hydrocarbon emissions were 31 Gg for CH4 and 22.7 Gg for NMVOC. The emission of BC, which is one of the main short-lived climate forcers, totalled 1.6 Gg. Based on these results, satellite data demonstrate great potential for estimating emissions from rice croplands, having the advantages of timely availability and cost competitiveness.


Subject(s)
Air Pollutants , Environmental Monitoring , Oryza , Agriculture , Asia , Particulate Matter/analysis , Satellite Imagery , Vietnam
13.
Glob Chang Biol ; 26(3): 1532-1575, 2020 03.
Article in English | MEDLINE | ID: mdl-31637793

ABSTRACT

There is a clear need for transformative change in the land management and food production sectors to address the global land challenges of climate change mitigation, climate change adaptation, combatting land degradation and desertification, and delivering food security (referred to hereafter as "land challenges"). We assess the potential for 40 practices to address these land challenges and find that: Nine options deliver medium to large benefits for all four land challenges. A further two options have no global estimates for adaptation, but have medium to large benefits for all other land challenges. Five options have large mitigation potential (>3 Gt CO2 eq/year) without adverse impacts on the other land challenges. Five options have moderate mitigation potential, with no adverse impacts on the other land challenges. Sixteen practices have large adaptation potential (>25 million people benefit), without adverse side effects on other land challenges. Most practices can be applied without competing for available land. However, seven options could result in competition for land. A large number of practices do not require dedicated land, including several land management options, all value chain options, and all risk management options. Four options could greatly increase competition for land if applied at a large scale, though the impact is scale and context specific, highlighting the need for safeguards to ensure that expansion of land for mitigation does not impact natural systems and food security. A number of practices, such as increased food productivity, dietary change and reduced food loss and waste, can reduce demand for land conversion, thereby potentially freeing-up land and creating opportunities for enhanced implementation of other practices, making them important components of portfolios of practices to address the combined land challenges.


Subject(s)
Agriculture , Climate Change , Acclimatization , Conservation of Natural Resources , Food Supply
14.
Environ Monit Assess ; 171(1-4): 381-94, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20033278

ABSTRACT

This paper presents monitoring results of daily brick kiln stack emission and the derived emission factors. Emission of individual air pollutant varied significantly during a firing batch (7 days) and between kilns. Average emission factors per 1,000 bricks were 6.35-12.3 kg of CO, 0.52-5.9 kg of SO(2) and 0.64-1.4 kg of particulate matter (PM). PM emission size distribution in the stack plume was determined using a modified cascade impactor. Obtained emission factors and PM size distribution data were used in simulation study using the Industrial Source Complex Short-Term (ISCST3) dispersion model. The model performance was successfully evaluated for the local conditions using the simultaneous ambient monitoring data in 2006 and 2007. SO(2) was the most critical pollutant, exceeding the hourly National Ambient Air Quality Standards over 63 km(2) out of the 100-km(2) modelled domain in the base case. Impacts of different emission scenarios on the ambient air quality (SO(2), PM, CO, PM dry deposition flux) were assessed.


Subject(s)
Air Pollutants/analysis , Air Pollution , Construction Materials , Environmental Monitoring/methods , Industry , Humans , Particle Size , Particulate Matter/analysis , Vietnam
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