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•P removal from simulated wastewater using lab-scale HSSF-CWs was examined.•Paspalum atratum was utilized as the emergent wetland plant for very first time.•WHC-based HSSF-CW planted ...with Paspalum atratum removed up to 89.9% of inflow P.•WHC sorption was the dominant P removal pathway in HSSF-CWs.•Utilizing WHC as a reactive filter media apparently extended lifespans of HSSF-CWs.
This work examined the phosphorus (P) removal from the synthetic pretreated swine wastewater using lab-scale horizontal sub-surface flow constructed wetlands (HSSF-CWs). White hard clam (Meretrix lyrata) shells (WHC) and Paspalum atratum were utilized as substrate and plant, respectively. The focus was placed on treatment performance, removal mechanisms and lifespan of the HSSF-CWs. Results indicated that WHC-based HSSF-CW with P. atratum exhibited a high P removal (89.9%). The mean P efluent concentration and P removal rate were 1.34 ± 0.95 mg/L and 0.32 ± 0.03 g/m2/d, respectively. The mass balance study showed that media sorption was the dominant P removal pathway (77.5%), followed by microbial assimilation (14.5%), plant uptake (5.4%), and other processes (2.6%). It was estimated the WHC-based bed could work effectively for approximately 2.84 years. This WHC-based HSSF-CWs technology will therefore pave the way for recycling Ca-rich waste materials as media in HSSF-CWs to enhance P-rich wastewater purification.
The aim of this study was to examine the effect of different reference ranges in bone mineral density on the diagnosis of osteoporosis.
This cross-sectional study involved 357 men and 870 women aged ...between 18 and 89 years, who were randomly sampled from various districts within Ho Chi Minh City, Vietnam. BMD at the femoral neck, lumbar spine and whole body was measured by DXA (Hologic QDR4500). Polynomial regression models and bootstraps method were used to determine peak BMD and standard deviation (SD). Based on the two parameters, we computed T-scores (denoted by TVN) for each individual in the study. A similar diagnosis was also done based on T-scores provided by the densitometer (TDXA), which is based on the US White population (NHANES III). We then compared the concordance between TVN and TDXA in the classification of osteoporosis. Osteoporosis was defined according to the World Health Organization criteria.
In post-menopausal women, the prevalence of osteoporosis based on femoral neck TVN was 29%, but when the diagnosis was based on TDXA, the prevalence was 44%. In men aged 50+ years, the TVN-based prevalence of osteoporosis was 10%, which was lower than TDXA-based prevalence (30%). Among 177 women who were diagnosed with osteoporosis by TDXA, 35% were actually osteopenia by TVN. The kappa-statistic was 0.54 for women and 0.41 for men.
These data suggest that the T-scores provided by the Hologic QDR4500 over-diagnosed osteoporosis in Vietnamese men and women. This over-diagnosis could lead to over-treatment and influence the decision of recruitment of participants in clinical trials.
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•In the presence of both K+ and Ca2+, K+ initiates gelation of κ-car.•In the presence of both K+ and Ca2+, Ca2+ initiates gelation of ι-car.•Mixing K+ and Ca2+ has a synergistic ...effect on the gel stiffness.•Mixed ι-car /κ-car gels are more homogeneous than κ-car gels.•Structure and rheology of mixed ι-car /κ-car gels can be tuned by mixing K+ and Ca2+.
The effect was studied of adding both KCl and CaCl2 on gelation of solutions of ι-carrageenan, κ-carrageenan and mixtures of both types. The gel temperature (Tg) of ι-car was found to be determined by the CaCl2 concentration and Tg of κ-car by the KCl concentration. At a given salt concentration, ι-car was stiffest with pure CaCl2, but κ-car gels and mixed carrageenan gels were stiffer when both KCl and CaCl2 were present. Gelation of κ-car increased the turbidity of mixed carrageenan gels in the presence of KCl or CaCl2, but when both salts were present it led to a drop of the turbidity. In mixed salt, K+ induces formation of a homogeneous κ-car network that causes the mixed network to become more homogeneous. Rheological and structural properties of carrageenan gels can be tuned for a given polymer and salt concentration by adding both KCl and CaCl2 to κ-car/ι-car mixtures.
The conversion of solar energy into hydrogen via water splitting process is one of the key sustainable technologies for future clean, storable, and renewable source of energy. Therefore, development ...of visible light-responsive and efficient photocatalyst material has been of immense interest, but with limited success. Here, we show that overall water splitting under visible-light irradiation can be achieved using a single photocatalyst material. Multiband InGaN/GaN nanowire heterostructures, decorated with rhodium (Rh)/chromium-oxide (Cr2O3) core–shell nanoparticles can lead to stable hydrogen production from pure (pH ∼ 7.0) water splitting under ultraviolet, blue and green-light irradiation (up to ∼560 nm), the longest wavelength ever reported. At ∼440–450 nm wavelengths, the internal quantum efficiency is estimated to be ∼13%, the highest value reported in the visible spectrum. The turnover number under visible light well exceeds 73 in 12 h. Detailed analysis further confirms the stable photocatalytic activity of the nanowire heterostructures. This work establishes the use of metal-nitrides as viable photocatalyst for solar-powered artificial photosynthesis for the production of hydrogen and other solar fuels.
The escalation of dengue fever (DF) cases in recent years and the occurrence of a large-scale DF outbreak in 2017 underline the importance of dengue vaccines in Vietnam. Given the potential benefits ...of the dengue vaccines and the need for copayment by the private sector, this study aims to evaluate the willingness to pay (WTP) for the dengue vaccines in patients with DF in Northern Vietnam.
A cross-sectional study was conducted on 330 in-and-out patients with DF admitted to the Bach Mai Hospital. We used the contingent valuation method to evaluate the WTP for dengue vaccines. Socioeconomic and clinical characteristics were also investigated. Multivariate interval and logistic regression models were used to estimate the average amount of WTP and identify the factors associated with the WTP.
Around 77.3% patients were willing to pay an average amount of US$ 67.4 (95% CI=57.4-77.4) for the vaccine. People of higher ages, those having health insurance, those traveling in the past 15 days or suffering from anxiety/depression were less likely to be willing to pay for the dengue vaccine. However, people having a longer duration of DF or having problems with mobility were positively associated with WTP for the dengue vaccine. Patients educated to more than high school levels (Coeff.=31.31; 95% CI=3.26-59.35), those in the richest quintile (Coeff.=62.76; 95% CI=25.40; 100.13), or those having a longer duration of the disease (Coeff.=6.18; 95% CI=0.72-11.63) were willing to pay a higher amount.
This study highlights a relatively high rate and amount of WTP for the dengue vaccine among patients with DF. Psychological counseling services as well as educational campaigns should be undertaken to improve the WTP for the vaccine. Moreover, government subsidies should be given to increase the coverage of the vaccine in the future, especially for the poor.
Regeneration capacity declines with age, but why juvenile organisms show enhanced tissue repair remains unexplained. Lin28a, a highly conserved RNA-binding protein expressed during embryogenesis, ...plays roles in development, pluripotency, and metabolism. To determine whether Lin28a might influence tissue repair in adults, we engineered the reactivation of Lin28a expression in several models of tissue injury. Lin28a reactivation improved hair regrowth by promoting anagen in hair follicles and accelerated regrowth of cartilage, bone, and mesenchyme after ear and digit injuries. Lin28a inhibits let-7 microRNA biogenesis; however, let-7 repression was necessary but insufficient to enhance repair. Lin28a bound to and enhanced the translation of mRNAs for several metabolic enzymes, thereby increasing glycolysis and oxidative phosphorylation (OxPhos). Lin28a-mediated enhancement of tissue repair was negated by OxPhos inhibition, whereas a pharmacologically induced increase in OxPhos enhanced repair. Thus, Lin28a enhances tissue repair in some adult tissues by reprogramming cellular bioenergetics.
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•Lin28a reactivation promotes hair regrowth, as well as ear and digit tissue repair•Excess let-7 inhibits tissue repair, but anti-let-7 therapy fails to promote tissue repair•Lin28a promotes tissue repair by enhancing the translation of some oxidative enzymes•Lin28a’s enhancement of tissue repair was negated by OxPhos inhibition
Lin28, a regulator of embryogenesis and pluripotency, is found to promote tissue repair across various models of injury. Lin28 achieves this by enhancing the expression of several metabolic genes that ultimately promote repair.
Macrocyclization is a valuable tool for drug design and protein engineering. Although various methods have been developed to prepare macrocycles, a general and efficient strategy is needed. Here we ...report a highly efficient method using butelase 1 to macrocyclize peptides and proteins ranging in sizes from 26 to >200 residues. We achieved cyclizations that are 20,000 times faster than sortase A, the most widely used ligase for protein cyclization. The reactions completed within minutes with up to 95% yields.
Silicon-Carbide (SiC) MOSFETs, due to material properties, are designed with smaller thickness in the gate oxide and a higher electric field compared to Si MOSFETs. Consequently, the SiC MOSFETs have ...a worse reliability which causes higher leakage currents during instantaneous abnormal operating conditions. This paper investigates the reliability issues of the SiC MOSFET gate oxide under standard short-circuit test conditions. In this paper, 1200-V SiC MOSFETs are newly modeled, and also their short-circuit sustainability (tolerance) have been studied at different drain-source and gate-source voltages. A hardware tester circuit was designed and developed to test the devices under such extreme circuit conditions. Then, the gate reliability of SiC MOSFET devices have been compared to that of Si power devices of similar ratings. The results reveal a higher reduction in the instantaneous gate-source voltage of SiC MOSFETs compared to that of Si devices under the same operating conditions. The gate-voltage reduction phenomenon results from the higher leakage currents through the gate. Furthermore, it was found that the gate-source voltage reduction during the test depends on the gate structures. The gate voltage reduction of SiC MOSFETs with planar gate is higher than that of MOSFETs with shield planar gate. As the pulse duration increases in short-circuit tests, the leakage current in the gate-source of SiC devices increases. The results show that even though the SiC MOSFETs are very capable of processing long pulses and high power in the drain-source, the gate-source side is highly degraded by these pulses in the test. Moreover, whenever a small number of the short-circuit tests are applied, the gate structure of SiC MOSFETs becomes broken while the drain-source is still able to block the dc-link voltage. The paper concludes that the short-circuit reliability of the gate was found to be worse compared with commercial Si devices with similar rating.
A convergent brush-first ring-opening metathesis polymerization (ROMP) approach for the synthesis of mikto-brush-arm star polymers (MBASPs) via cross-linking of dissimilar bottlebrush polymers is ...reported. Living bottlebrush polymers prepared via ROMP of norbornene-terminated poly(ethylene glycol) (PEG) or polystyrene (PS) macromonomers (MMs) were mixed together in a desired ratio and exposed to a bis-norbornene cross-linker to yield MBASPs with narrow size distributions. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the solution morphologies of MBASPs depended on the feed ratio of the PEG and PS bottlebrush polymers at the cross-linking stage. This work provides a robust and modular strategy for the synthesis of a new type of miktoarm star polymer wherein the star arms are bottlebrush polymers.
There is an increasing interest in a fast-growing machine learning technique called Federated Learning (FL), in which the model training is distributed over mobile user equipment (UEs), exploiting ...UEs' local computation and training data. Despite its advantages such as preserving data privacy, FL still has challenges of heterogeneity across UEs' data and physical resources. To address these challenges, we first propose FEDL , a FL algorithm which can handle heterogeneous UE data without further assumptions except strongly convex and smooth loss functions. We provide a convergence rate characterizing the trade-off between local computation rounds of each UE to update its local model and global communication rounds to update the FL global model. We then employ FEDL in wireless networks as a resource allocation optimization problem that captures the trade-off between FEDL convergence wall clock time and energy consumption of UEs with heterogeneous computing and power resources. Even though the wireless resource allocation problem of FEDL is non-convex, we exploit this problem's structure to decompose it into three sub-problems and analyze their closed-form solutions as well as insights into problem design. Finally, we empirically evaluate the convergence of FEDL with PyTorch experiments, and provide extensive numerical results for the wireless resource allocation sub-problems. Experimental results show that FEDL outperforms the vanilla FedAvg algorithm in terms of convergence rate and test accuracy in various settings.
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