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•The SCG derived biochars pyrolyzed at 300 and 500 °C had the lowest PAHs levels.•The PAHs levels in all biochars and pyrolysis oil met the related regulations.•The SCG 500 showed the ...highest tetracycline adsorption capacity.•pH affected tetracycline adsorption.•Surface interactions were major adsorption reactions.
The main objective of this study was to evaluate the effect of different pyrolysis temperatures on the formation of polycyclicaromatichydrocarbons (PAHs) in biochar originated spent coffee ground (SCG) and the tetracycline (TC) adsorption behavior of biochar in water. The results showed that biochar synthesized at 500 °C (SCG 500) contained low PAHs (600 µg kg−1) and the highest TC adsorption efficiency. In addition, the characteristics, influencing factors on TC adsorption, and the related mechanisms of SCG 500 were comprehensively investigated. The results showed that the highest efficiency was observed at pH of 7 and the presence of ions in salinity solution reduced the adsorption capacity of SCG 500. The electrostatic interaction, hydrogen bonding, and π-EDA were the major adsorption mechanisms. Safety PAHs level, low-cost, widely material sources and high TC removal capacity suggested that SCG 500 was a promising environmentally friendly effective absorbent.
Tetanus remains common in many low- and middle-income countries, but as critical care services improve, mortality from tetanus is improving. Nevertheless, patients develop severe syndromes associated ...with autonomic nervous system disturbance (ANSD) and the requirement for mechanical ventilation (MV). Understanding factors associated with worse outcome in such settings is important to direct interventions. In this study, we investigate risk factors for disease severity and long-term physical outcome in adults with tetanus admitted to a Vietnamese intensive care unit.
Clinical and demographic variables were collected prospectively from 180 adults with tetanus. Physical function component scores (PCS), calculated from Short Form Health Survey (SF-36), were assessed in 79 patients at hospital discharge, 3 and 6 months post discharge.
Age, temperature, heart rate, lower peripheral oxygen saturation (SpO
) and shorter time from first symptom to admission were associated with MV (OR 1.03 95% confidence interval (CI) 1.00, 1.05, p = 0.04; OR 2.10 95% CI 1.03, 4.60, p = 0.04; OR 1.04 95% CI 1.01, 1.07, p = 0.02); OR 0.80 95% CI 0.66, 0.94, p = 0.02 and OR 0.65 95% CI 0.52, 0.79, p < 0.001, respectively). Heart rate, SpO
and time from first symptom to admission were associated with ANSD (OR 1.03 95% CI 1.01, 1.06, p < 0.01; OR 0.95 95% CI 0.9, 1.00, p = 0.04 and OR 0.64 95% CI 0.48, 0.80, p < 0.01, respectively). Median interquartile range PCS at hospital discharge, 3 and 6 months were 32.37 24.95-41.57, 53.0 41.6-56.3 and 54.8 51.6-57.3, respectively. Age, female sex, admission systolic blood pressure, admission SpO
, MV, ANSD, midazolam requirement, hospital-acquired infection, pressure ulcer and duration of ICU and hospital stay were associated with reduced 0.25 quantile PCS at 6 months after hospital discharge.
MV and ANSD may be suitable endpoints for future research. Risk factors for reduced physical function at 3 months and 6 months post discharge suggest that modifiable features during hospital management are important determinants of long-term outcome.
Dengue shock (DS) is the most severe complication of dengue infection; endothelial hyperpermeability leads to profound plasma leakage, hypovolaemia and extravascular fluid accumulation. At present, ...the only treatment is supportive with intravenous fluid, but targeted endothelial stabilising therapies and host immune modulators are needed. With the aim of prioritising potential therapeutics, we conducted a prospective observational study of adults (≥16 years) with DS in Vietnam from 2019-2022, comparing the pathophysiology underlying circulatory failure with patients with septic shock (SS), and investigating the association of biomarkers with clinical severity (SOFA score, ICU admission, mortality) and pulmonary vascular leak (daily lung ultrasound for interstitial and pleural fluid). Plasma was collected at enrolment, 48 hours later and hospital discharge. We measured biomarkers of inflammation (IL-6, ferritin), endothelial activation (Ang-1, Ang-2, sTie-2, VCAM-1) and endothelial glycocalyx breakdown (hyaluronan, heparan sulfate, endocan, syndecan-1). We enrolled 135 patients with DS (median age 26, median SOFA score 7, 34 required ICU admission, 5 deaths), together with 37 patients with SS and 25 healthy controls. Within the DS group, IL-6 and ferritin were associated with admission SOFA score (IL-6: βeta0.70, p<0.001 & ferritin: βeta0.45, p<0.001), ICU admission (IL-6: OR 2.6, p<0.001 & ferritin: OR 1.55, p<0.001) and mortality (IL-6: OR 4.49, p = 0.005 & ferritin: OR 13.8, p = 0.02); both biomarkers discriminated survivors and non-survivors at 48 hours and all patients who died from DS had pre-mortem ferritin ≥100,000ng/ml. IL-6 most strongly correlated with severity of pulmonary vascular leakage (R = 0.41, p<0.001). Ang-2 correlated with pulmonary vascular leak (R = 0.33, p<0.001) and associated with SOFA score (β 0.81, p<0.001) and mortality (OR 8.06, p = 0.002). Ang-1 was associated with ICU admission (OR 1.6, p = 0.005) and mortality (OR 3.62, p = 0.006). All 4 glycocalyx biomarkers were positively associated with SOFA score, but only syndecan-1 was associated with ICU admission (OR 2.02, p<0.001) and mortality (OR 6.51, p<0.001). This study highlights the central role of hyperinflammation in determining outcomes from DS; the data suggest that anti-IL-1 and anti-IL-6 immune modulators and Tie2 agonists may be considered as candidates for therapeutic trials in severe dengue.
In this article, the nonlinear dynamic response and free vibration of functionally graded porous (FGP) truncated conical panel with piezoelectric actuators in thermal environments are investigated by ...an analytical method. The panel resting on an elastic foundation which is modeled according to the Winkler–Pasternak theory. The material properties including Young's modulus, shear modulus, and density are assumed to smoothly through the shell thickness. Three types of porosity distribution across the thickness, namely, symmetric porosity distribution, non-symmetric porosity, and uniform porosity distribution, are considered. Theoretical formulations are presented based on the first-order shear deformation shell theory with a von Karman-Donnell type of kinematic nonlinearity. The non-linear motion equations and resulting equations are derived by using Hamilton's principle, Galerkin's method, and Runge-Kutta method. Lastly, some numerical results are presented to study the effects of shell characteristics, porosity distribution, porosity coefficient, applied actuator voltage, temperature increment and elastic foundations on the nonlinear dynamic response and the natural frequencies of the piezoelectric FGP truncated conical panel.
•Nonlinear dynamic response and free vibration.•Piezoelectric functionally graded porous (FGP) truncated conical panel.•Using the first-order shear deformation shell theory.•Galerkin's method and Runge-Kutta method.•Symmetric porosity distribution, non-symmetric porosity, and uniform porosity.
The rise in Plasmodium falciparum resistance to dihydroartemisinin-piperaquine in Vietnam justifies the need to evaluate alternative artemisinin-based combination therapies. Between July 2018 and ...October 2019, a single-arm trial of pyronaridine-artesunate (Pyramax, PA) was conducted in Dak Nong province, Vietnam. PA (3-day course) was administered to adults and children infected with P. falciparum. PA was well tolerated by the participants. The proportion of patients with Day 42 PCR-corrected adequate clinical and parasitological response was 95.2% (95% confidence interval CI, 82.3 to 98.8,
= 40/42) for treating falciparum malaria. The median parasite clearance half-life was 6.7 h (range, 2.6 to 11.9) and the median parasite clearance time was 72 h (range, 12 to 132) with 44.9% (22/49) of patients having positive blood films at 72 h. The two patients that recrudesced had comparable Day 7 blood pyronaridine concentrations (39.5 and 39.0 ng/ml) to the 40 patients who did not recrudesce (median 43.4 ng/ml, 95% CI, 35.1 to 54.9). Ring-stage and piperaquine survival assays revealed that of the 29 P. falciparum isolates collected from the patients before PA treatment, 22 (75.9%) had reduced susceptibility to artemisinins and 17 (58.6%) were resistant to piperaquine. Genotyping confirmed that 92.0% (46/50) of falciparum patients were infected with parasites bearing the
C580Y mutation associated with artemisinin resistance. Of these, 56.0% (28/50) of the isolates also had multiple copies of the
2/3 genes responsible for piperaquine resistance. Overall, PA was effective in treating P. falciparum in the Central Highlands of Vietnam. (This study has been registered at AustralianClinicalTrials.gov.au under trial ID ACTRN12618001429246.).
We studied the development and persistence of neutralizing antibodies against SARS-CoV-2 ancestral strain, and Delta and Omicron (BA.1 and BA.2) variants in Vietnamese healthcare workers (HCWs) up to ...15 weeks after booster vaccination. We included 47 HCWs, including group 1 (G1, N = 21) and group 2 (G2; N = 26) without and with breakthrough Delta variant infection before booster immunization, respectively). The study participants had completed primary immunization with ChAdOx1-S and booster vaccination with BNT162b2. Neutralizing antibodies were measured using a surrogate virus neutralization assay. Of the 21 study participants in G1, neutralizing antibodies against ancestral strain, Delta variant, BA.1, and BA.2 were (almost) abolished at month 8 after the second dose, but all had detectable neutralizing antibodies to the study viruses at week 2 post booster dose. Of the 26 study participants in G2, neutralizing antibody levels to BA.1 and BA.2 were significantly higher than those to the corresponding viruses measured at week 2 post breakthrough infection and before the booster dose. At week 15 post booster vaccination, neutralizing antibodies to BA.1 and BA.2 dropped significantly, with more profound changes observed in those without breakthrough Delta variant infection. Booster vaccination enhanced neutralizing activities against ancestral strain and Delta variant compared with those induced by primary vaccination. These responses were maintained at high levels for at least 15 weeks. Our findings emphasize the importance of the first booster dose in producing cross-neutralizing antibodies against Omicron variant. A second booster to maintain long-term vaccine effectiveness against the currently circulating variants merits further research.
In this work, a feasible one-pot approach to synthesize manganese oxide/graphene composites, the so-called plasma-enhanced electrochemical exfoliation process (PE3P), has been developed. Herein, a ...composite of graphene decorated with manganese oxide nanoparticles was prepared via PE3P from a KMnO4 solution and graphite electrode under a voltage of 70 V in an ambient environment. By controlling the initial KMnO4 concentration, we obtained distinct MnO2/graphene samples. The prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and Raman spectroscopy. The electrochemical measurements of the MnO2/graphene composites revealed that the specific capacitance of the samples is approximately 320 F g-1 at a scan rate of 10 mV s-1, which is comparably very high for manganese oxide/carbon-based supercapacitor electrode materials. Considering the simple, low-cost, one-step and environmentally friendly preparation, our approach has the potential to be used for the fabrication of MnO2/graphene composites as the electrode materials of supercapacitors.
Carbon aerogel was prepared from waste corn stalk following a four-step process: (1) purification of cellulose, (2) gelation, (3) carbonization and (4) activation. Different amounts of urea as ...gelation agent were employed to investigate their effect on the characteristics of carbon aerogel as well as the electrochemical properties and desalination capability of carbon aerogel electrode. ACCA-1.5 sample (cellulose:urea ratio of 1:1.5) possessed the largest BET surface area of 713 m
2
g
−1
with 76.88% micropores, the highest specific capacitance of 67.2 F g
−1
, and the highest SAC value of 22.19 mg g
−1
after 1415 s. These results propose an effective method to exploit the cheap and abundant waste biomass to fabricate MCDI electrodes in the desalination process.
Background. Dengue endangers billions of people in the tropical world, yet no therapeutic is currently available. In part, the severe manifestations of dengue reflect inflammatory processes affecting ...the vascular endothelium. In addition to lipid lowering, statins have pleiotropic effects that improve endothelial function, and epidemiological studies suggest that outcomes from a range of acute inflammatory syndromes are improved in patients already on statin therapy. Methods. Following satisfactory review of a short pilot phase (40 mg lovastatin vs placebo in 30 cases), we performed a randomized, double-blind, placebo-controlled trial of 5 days of 80 mg lovastatin vs placebo in 300 Vietnamese adults with a positive dengue NS1 rapid test presenting within 72 hours of fever onset. The primary outcome was safety. Secondary outcomes included comparisons of disease progression rates, fever clearance times, and measures of plasma viremia and quality of life between the treatment arms. Results. Adverse events occurred with similar frequency in both groups (97/151 64% placebo vs 82/149 55% lovastatin; P = .13), and were in keeping with the characteristic clinical and laboratory features of acute dengue. We also observed no difference in serious adverse events or any of the secondary outcome measures. Conclusions. We found lovastatin to be safe and well tolerated in adults with dengue. However, although the study was not powered to address efficacy, we found no evidence of a beneficial effect on any of the clinical manifestations or on dengue viremia. Continuing established statin therapy in patients who develop dengue is safe. Clinical Trials Registration. ISRCTN03147572.
Hand, foot and mouth disease (HFMD) is highly prevalent in the Asia Pacific region, particularly in Vietnam. To develop effective interventions and efficient vaccination programs, we inferred the ...age-time-specific transmission patterns of HFMD serotypes enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6), coxsackievirus A10 (CV-A10), coxsackievirus A16 (CV-A16) in Ho Chi Minh City, Vietnam from a case data collected during 2013–2018 and a serological survey data collected in 2015 and 2017. We proposed a catalytic model framework with good adaptability to incorporate maternal immunity using various mathematical functions. Our results indicate the high-level transmission of CV-A6 and CV-A10 which is not obvious in the case data, due to the variation of disease severity across serotypes. Our results provide statistical evidence supporting the strong association between severe illness and CV-A6 and EV-A71 infections. The HFMD dynamic pattern presents a cyclical pattern with large outbreaks followed by a decline in subsequent years. Additionally, we identify the age group with highest risk of infection as 1-2 years and emphasise the risk of future outbreaks as over 50% of children aged 6-7 years were estimated to be susceptible to CV-A16 and EV-A71. Our study highlights the importance of multivalent vaccines and active surveillance for different serotypes, supports early vaccination prior to 1 year old, and points out the potential utility for vaccinating children older than 5 years old in Vietnam.
•We proposed a modified catalytic model framework with maternal immunity.•We made use jointly of case and serology data to estimate transmission intensity.•The results reveal the high-level transmission of coxsackievirus A6, A10 in Vietnam.•The results identify the age with highest infection risk as 1-2 years old.•This study emphasises the importance of multivalent vaccines and active surveillance.
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