With the emergence of new transport technologies, ride-hailing services have become increasingly popular around the world in recent years. Particularly in developing countries where public transport ...(PT) systems are normally poor due to the lack of investment, these services have become more prevalent as they are considered as a form of PT mode. Thus, understanding the loyalty intention of ride-hailing passengers is important as it is seen to be a prime determinant of long-term financial performance. Additionally, the operation of these services can increase urban mobility, which can lead to an increase in local spending and government revenue. The aim of this study is to understand better the complexities of factors influencing ride-hailing passenger satisfaction and loyalty intention. The data collected by surveying 559 ride-hailing passengers in Vietnam was analysed using a Partial Least Squares - Structural Equation Modelling (PLS-SEM) approach. The findings show that three factors including perceived benefits of the booking app, perceived sales promotion and perceived service quality have direct influences on passenger satisfaction and loyalty in which perceived service quality is more important than the other factors. Insight into the perceptions of passengers provides ride-hailing firms and even their competitors (traditional taxi services) with managerial implications aiming to maintain and increase patronage.
Antimicrobial-resistant infections are a major global health issue. Ease of antimicrobial access in developing countries is proposed to be a key driver of the antimicrobial resistance (AMR) epidemic ...despite a lack of community antimicrobial usage data.
Using a mixed-methods approach (geospatial mapping, simulated clients, healthcare utilization, longitudinal cohort) we assessed antimicrobial access in the community and quantified antimicrobial usage for childhood diarrhoea in an urban Vietnamese setting.
The study area had a pharmacy density of 15.7 pharmacies/km2 (a pharmacy for every 1316 people). Using a simulated client method at pharmacies within the area, we found that 8% (3/37) and 22% (8/37) of outlets sold antimicrobials for paediatric watery and mucoid diarrhoea, respectively. However, despite ease of pharmacy access, the majority of caregivers would choose to take their child to a healthcare facility, with 81% (319/396) and 88% (347/396) of responders selecting a specialized hospital as one of their top three preferences when seeking treatment for watery and mucoid diarrhoea, respectively. We calculated that at least 19% (2688/14 427) of diarrhoea episodes in those aged 1 to <5 years would receive an antimicrobial annually; however, antimicrobial usage was almost 10 times greater in hospitals than in the community.
Our data question the impact of community antimicrobial usage on AMR and highlight the need for better education and guidelines for all professionals with the authority to prescribe antimicrobials.
Green macroalgae have gained attention as promising renewable sources for biorefining. Despite the wide potential availability of green macroalgae, their utilization has been limited to ethanol ...production, hindering their further application. In this study, we report that a bacterium,
Halomonas
sp. strain BL6 (isolated from a mangrove forest in Bach Long, Nam Dinh Province, Vietnam), produces pyruvate from a saccharified solution of the green seaweed
Ulva reticulata
and secretes it into the medium. Pyruvate, an important α-oxocarboxylic acid, plays a central role in energy and carbon metabolism in living organisms and is used mainly for the synthesis of various chemicals and polymers or as an ingredient or additive in food, cosmetics, and pharmaceuticals. To investigate the possibility of using
U. reticulata
from the seashore of Vietnam as biomass feedstock, the chemical composition and saccharification yield of this seaweed were studied. Dry biomass of
U. reticulata
was found to contain 65.5% carbohydrate, 10.3% protein, 1.8% lipid, and 10.6% ash. Reducing sugar content reached 608.79 mg g
−1
of biomass after pretreatment with diluted acid and 24 h of incubation with 50 IU g
−1
Viscozyme L. The resulting sugars were fermented by
Halomonas
sp. strain BL6 to produce pyruvate, and the maximal pyruvate concentration reached 55.23 g L
−1
after 72 h of cultivation. This study is the first to report the production of valuable compounds other than bioethanol products, such as pyruvate, from
U. reticulata
hydrolysate by a
Halomonas
strain.
This study investigated the biomass production process from the laboratory to the pilot scale in order to use the nutrient-rich biomass of the diatom
Thalassiosira weissflogii
as live feed for ...white-leg shrimp (
Litopenaeus vannamei
) at larval stages (zoeal, mysis, and postlarval) and in commercial production in hatcheries in Vietnam. Our results showed that
T
.
weissflogii
was successfully cultured in 1–2 L Erlenmeyer flasks, 0.2–3.5 m
3
composite tanks, and 6.5 m
3
tubular photobioreactors, with the highest cell density of 1.6 × 10
6
cells mL
−1
reached after 6 days of culture. Under optimal culture conditions, the protein, lipid, and carbohydrate contents in this algal biomass were 13.2%, 20.0%, and 10.0% of dry cell weight, respectively. The fatty acid composition contains high amount of palmitic acid (C16:0, 43.11% of total fatty acid), and polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA, C20:5ω-3), approximated 16.5% of total fatty acid. In a 50 L larval rearing tank, at the optimal stocking density of 125 nauplii L
−1
, the survival percentage (75.55%), the total body length (from 5.376 ± 0.007 to 10.860 ± 0.030 mm), and weight (at from PL
1
to PL
12
stages) (from 0.145 ± 0.002 to 1.158 ± 0.005 g) of the white-leg shrimp larvae reached the highest values but the metamorphosis time (234 h) was shortest compared with the other stocking densities. Further, adding living
T
.
weissflogii
biomass to the diet of white-leg shrimp larvae at the nauplii 6 stage led to an increase in the body length, weight, and survival percentage of white-leg shrimp larvae of 21.17%, 35.7%, and 33% higher compared with those of larvae fed the control diet (without the addition of
T
.
weissflogii
), respectively. At the same time, the metamorphosis time of larvae (from Z
1
to PL
1
) decreased by 4 h compared to the control group. In intensive ponds (area of 6400 m
2
pond
−1
), using seed stocks at the postlarvae 12 stage that had been fed
T
.
weissflogii
, the final weight, yield, and survival percentage of the shrimp were increased by 7.3%, 14.2%, and 16.3%, respectively, compared with those of the control group. There were no statistically significant differences in the protein and carbohydrate contents in the shrimp flesh among the experimental and control group (
p
> 0.05). The lipid, omega-3, omega-6, and omega-9 fatty acid contents of shrimp flesh in experiment formula (per 100 g shrimp) were 1.21 g, 72.9 mg, 114 mg, and 86.1 mg, 11%, 29%, 21.6%, and 17.7% higher than that those in control, respectively. The obtained results show the great potential of using
T
.
weissflogii
as live feed on white-leg shrimp farms in Vietnam.
In manipulating the assembly of micro-components, the symmetrical microgripper mechanism often causes destruction, damaging those components during manipulation, due to the phenomenon of non-uniform ...clamping force output from the clamp. From this disadvantage, a new asymmetric microgripper structure is proposed with stable output clamping force. The asymmetric microgripper structure will have a smaller output displacement than that of the symmetric structure. Therefore, to increase the output displacement gain, a flexible hinge with a triple-stair half-bridge-style mechanism (TSBM) is adopted to design the amplifier of the asymmetrical microgripper. The finite element method is applied to analyze the displacement and stress. The optimization process is performed based on the geometric parametric properties of the structure. Using the technology for order preference by similarity to ideal solution (TOPSIS) based on the Grey relationship analysis (GRA), we obtained the maximum displacement output and minimum stress. Results show that the maximum output displacement is 5,818 mm, and stress after analysis is 2,432 MPa. The test is conducted to verify the optimal results and the effectiveness of the optimization method. Finally, experimental experiments were performed, with a 4.8% difference from the FEA results. The results from the experimental test verify that the microgripper’s maximum displacement amplification ratio is approximately 58.2 times.
With outstanding mechanical advantages such as high strength, light weight, high rigidity, low thermal expansion, good resistance corrosion, and high vibration resistance, carbon fiber–reinforced ...polymer (CFRP) is becoming increasingly popular in the automotive, aerospace, and medical spheres. For the CFRP machining, the biggest drawback is the effect of moisture on the mechanical properties caused by the cooling liquid and tool geometry. The appreciable body of study on the influence of wetness on the mechanical quality of carbon fiber–reinforced plastic has shown that there is no suitable use for lubrication fluids in the composite industry. However, there is a significant impact on the CFRP machining capabilities caused by the geometry of the cutting tool and cryogenic liquid cooling. This paper investigated the optimal choice of the parametric combinations in the CFRP drilling process. The optimization method was proposed using the Fuzzy interference system based on grey relation analysis. The experiment data was designed according to the Taguchi method. The twist angle of the drill, the coolant gas, and the feed rate were considered as the parameter inputs while observing several multi-responses such as thrust force and temperature generated during drilling process. The optimal result, as well as the case with highest grey fuzzy reasoning grade (GFRG), indicated that the low feed rate combined with the high twist angle drill in the hybrid cryogenic CO
2
-N
2
gas condition tended to minimize the value of the response output. The verification experiment results showed a good correlation with the optimal analytical result. The analysis of variance results also showed that the reliability of the data was satisfactory.
Simultaneous induction of other types of programmed cell death, alongside apoptosis, in cancer cells may be considered an attractive strategy for the development of more effective anticancer ...therapies. The present study aimed to investigate the role of AMP‑activated protein kinase (AMPK) in nutrient/serum starvation‑induced necroptosis, which is a programmed form of necrosis, in the presence or absence of p53. The present study detected higher cell proliferation and lower cell death rates in the HCT116 human colon cancer cell line containing a p53 null mutation (HCT116 p53‑/‑) compared with in HCT116 cells harboring wild‑type p53 (HCT116 p53+/+), as determined using a cell viability assay. Notably, western blot analysis revealed a relatively lower level of necroptosis in HCT116 p53‑/‑ cells compared with in HCT116 p53+/+ cells. Investigating the mechanism, it was revealed that necroptosis may be induced in HCT116 p53+/+ cells by significantly increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP), whereas little alterations were detected in HCT116 p53‑/‑ cells. Unexpectedly, a much lower level of ATP was detected in HCT116 p53‑/‑ cells compared with in HCT116 p53+/+ cells. Accordingly, AMPK phosphorylation on the Thr172 residue was markedly increased in HCT116 p53‑/‑ cells. Furthermore, western blot analysis and ROS measurements indicated that AMPK inhibition, using dorsomorphin dihydrochloride, accelerated necroptosis by increasing ROS generation in HCT116 p53‑/‑ cells. However, AMPK activation by AICAR did not suppress necroptosis in HCT116 p53+/+ cells. In conclusion, these data strongly suggested that AMPK activation may be enhanced in HCT116 p53‑/‑ cells under serum‑depleted conditions via a drop in cellular ATP levels. In addition, activated AMPK may be at least partially responsible for the inhibition of necroptosis in HCT116 p53‑/‑ cells, but not in HCT116 p53+/+cells.
Anthocyanin, a main bioactive compound found in Hibiscus sabdariffa L. extract, has attracted different fields such as food additives and functional foodstuffs due to its wide range of possible ...applications. However, commercial applications of anthocyanins as colourants and pharmaceuticals have been limited due to their defective extraction yield and poor stability. This study aimed to improve the extraction efficiency and enhance the stability of anthocyanin extracted from H. subdariffa L. The method of enzyme-microwave assisted extraction (EMAE, 15.37 ± 0.41 mg/g anthocyanin based on raw material) resulted in enhancing the anthocyanin recovery efficiency up to 15.35%, 23.68% and 28.04% compared to each technique of microwave-assisted extraction (MAE, 13.01 ± 0.22 mg/g), ultrasound-assisted extraction (UAE, 11.73 ± 0.28 mg/g) and enzyme-assisted extraction (EAE, 11.06 ± 0.33 mg/g). The FT-IR and UV–Vis spectra showed the identified characterization of anthocyanin. For stabilization, the colour deviation values of anthocyanin extract in cases of individuals adding catechin 1.5%, chitosan 2%, or chondroitin sulfate 3% were 9.22, 6.53, and 7.59, respectively, while the combination of the three co-pigments gave the lowest color deviation of 4.11 after 30 h investigation. This combined method prolonged the shelf-life of anthocyanin powder to 16.2 months and maintained its antioxidant activity by about 50%. In the trend of exploitation and application of bioactive components, this study would offer a promising approach to improve the extraction efficiency and the stability of anthocyanin from H. sabdariffa L. as well as valuable information for large-scale anthocyanin process and storage.
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•Extraction and stabilization conditions of Hibiscus sabdariffa L. anthocyanin were studied.•The method of enzyme-microwave-assisted extraction (EMAE) was the most effective.•Anthocyanin extraction yield of EMAE was 15.37 mg/g.•Catechin, chitosan and chondroitin sulfate were studied as co-pigments of anthocyanin.•The three co-pigments combination extended the shelf-life of anthocyanin powder by 6 months.