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Abstract A 44‐year‐old woman at 30 weeks of pregnancy was admitted to the Intensive Care Unit with a diagnosis of severe COVID‐19 pneumonia. Her condition worsened quickly, defined by prolonged hypoxia even with intensive therapy and oxygen supplementation. This led to the decision to perform a caesarean delivery and continue pulse corticosteroids therapy after delivery. Soon after she recovered from COVID‐19 pneumonia, her life was threatened again by septic shock from hospital‐acquired pneumonia. After nearly 1 month of hospitalization, she was discharged and fully recovered on the re‐examination day 10 months later.

In the current context, an attempt is being made to improve the electrical discharge machining (EDM) process by using powder particles in a suitable combination. To improve the quality of such procedures, the process parameters should be optimized. The present study proposes to utilize Taguchi–Grey relational analysis to discover the optimal combination of process parameters for SKD61 die steel specimens using titanium powder-mixed EDM (PMEDM). Among the machining parameters chosen, the optimal combination of current (3 A), pulse on-time (37 μs), pulse off-time (37 μs), and powder concentration (4 g/L) was determined experimentally. Due to its relevance in spark energy production, peak current is a more significant factor in PMEDM processes. A superior surface topography was obtained with increased microhardness and fewer microfractures over machined specimens with optimal process parameter in PMEDM. The titanium particles can effectively enhance the surface performance measures during PMEDM-based machining owing to tiny craters and pores with better lubrication.

Abstract Although stretchable electroluminescent (EL) devices have been the research hotspots for decades because of their enormous market value in lighting sources and displays, fabrication of the stretchable EL device through a simple, cost-effective, and scalable method still remains an open issue. Here, a novel all solution-processed method is developed to fabricate a high-performance alternative current electroluminescent (ACEL) device based on copper nanowires (Cu NWs). The Cu NW-based electrode exhibited a low resistance change of less than 10% after 1000 stretching cycles at a tensile strain of 30% and the resistance variation of the electrode in one stretching-releasing cycle was less than 1% at the 1000th. To substantiate suitability for the wearable application, the ACEL device was stretched at a tensile strain of 100% and it retained a luminance of 97.6 cd/m2. Furthermore, the device works well under different deformations such as bending, folding, rolling, and twisting. To the best of our knowledge, this is the first demonstration of Cu NWs applied in a stretchable ACEL, promising cost-effective electrode materials for various wearable electronics applications.

Diphtheria was once a leading cause of childhood death globally, but cases worldwide have been dramatically reduced over the few past decades by mass vaccination campaigns followed by routine childhood [...]

Clematis armandii has been used in many Chinese traditional patent medicines all over the world as a form of Caulis Clematidis Armandii. However, it has often been adulterated by Aristolochia manshuriensis, and Iodes vitiginea. A. manshuriensis must not be part of any herbal medicines because it contains aristolochic acid I, a nephrotoxin and potential carcinogen. The current pharmacopoeial methods have had limitation for differentiation of C. armandii from its adulterants. Thus, a specific, comprehensive, sensitive, and reproducible HPTLC/HPLC for quality control of C. armandii was proposed. Oleanolic acid from C. armandii has been isolated by vacuum liquid chromatography and column chromatography. The purified compound has been identified using Ultra Violet spectrophotometry (UV–Vis), Fourier Transform Infrared (FTIR), mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. Therefore, oleanolic acid should be detected for positive identification of Caulis Clematis Armandii. Minimum content of oleanolic acid can be evaluated by the validated HPTLC procedure proposed as well.

Abstract Despite improvements in medical care, the burden of sepsis remains high. In this study, we evaluated the incremental cost associated with postoperative sepsis and the impact of postoperative sepsis on clinical outcomes among surgical patients in Vietnam. We used the national database that contained 1,241,893 surgical patients undergoing seven types of surgery. We controlled the balance between the groups of patients using propensity score matching method. Generalized gamma regression and logistic regression were utilized to estimate incremental cost, readmission, and reexamination associated with postoperative sepsis. The average incremental cost associated with postoperative sepsis was 724.1 USD (95% CI 553.7–891.7) for the 30 days after surgery, which is equivalent to 28.2% of the per capita GDP in Vietnam in 2018. The highest incremental cost was found in patients undergoing cardiothoracic surgery, at 2,897 USD (95% CI 530.7–5263.2). Postoperative sepsis increased patient odds of readmission (OR = 6.40; 95% CI 6.06–6.76), reexamination (OR = 1.67; 95% CI 1.58–1.76), and also associated with 4.9 days longer of hospital length of stay among surgical patients. Creating appropriate prevention strategies for postoperative sepsis is extremely important, not only to improve the quality of health care but also to save health financial resources each year.

This experimental study investigates the effect of the cutting parameters of the Electrical Discharge Machining (EDM) process of Ti-6Al-4V alloy material on surface roughness (Ra), cutting time (t) and Material Removal Rate (MRR) then solve the Multiple Objective Optimization Problem using separate Multi-Criteria Decision-Making (MCDM) methods namely Entropy-Weighted TOPSIS (E-TOPSIS), MOORA, SAW, VIKOR, and WPM. Focusing on nine 3-levels variants including Operating Voltage (OV), Pulse-On Time (Ton), Pulse-Off Time (Toff), Short-Circuit Off Time (AFF), Secondary Voltage (SV), Feed Rate (WF), Tension (WT), Water Pressure (WL) and Material Cutting Speed (F). Due to the large number of variants studied, the Taguchi L27 experimental design was chosen to reduce the number of experiments while still ensuring reliability in assessing the impact of technological parameters on responses in the study. The optimization results from the different methods indicated two distinct optimal outcomes. According to the E-TOPSIS, MOORA, and SAW, the optimal result is a Ra of 3.27 μm, a t of 7.37 min, and an MRR of 7.45 mm3/min. This result suggests a balanced and harmonious optimization among all criteria. On the other hand, the figures VIKOR and WPM methods are 2.87 μm, 9.57 min, and 5.74 mm3/min, respectively. These results indicate a higher priority for certain criteria, reflected in the lower Ra, longer cutting time, and a smaller MRR in comparison to the figures for the remaining MCDM methods. The different optimal results achieved by various methods highlight that each method is suited to and excels with different sets of values. Therefore, in each specific research or production process, comparing and choosing results calculated by different methods provides a comprehensive view, aiding in making appropriate decisions. [ABSTRACT FROM AUTHOR]

This study investigates the influence of deflector length on the aerodynamic drag and flow characteristics of a standard 25° Ahmed body by a numerical approach. Two class of deflector was selected for investigation to elucidate the impact of angles parameter on both drag and flow characteristics. The first class has a fixed length of 9% of the slant's length and spanning angles from -25° to 25°. The second one has length varying from 0% to 100% of the slant's length deflectors and angles from -5° to 5°. Reynolds Average Navier-Stokes equations with the generalized k-ω (GEKO) model were selected. The numerical methods were conducted with the help of Ansys Fluent software. The numerical parameters of the model were adjusted to obtain the satisfying results of flow and drag. Numerical results were verified by experimental data at similar flow conditions. It was shown that the -5° defector allows for a reduction drag for all lengths tested with a maximum reducing drag of 19%. At the 5° deflector, 14% of the drag reduction was observed when its length is 0.3 length of the slant. For longer deflector lengths, the drag increases again. The deflector shows a good passive technique for drag reduction. However, parameters of the deflector should be carefully investigated and selected. The detailed skin-friction structure, pressure distribution, and wake flow fields relating to the drag behavior are analyzed in this study. [ABSTRACT FROM AUTHOR]

Objective: The Knema genus contains various naturally occurring secondary metabolites with pharmacological potential, including antitumor, neuroprotective, antidiabetic, and hepatoprotective activities. This study focuses on identifying nitric oxide production inhibitors from Vietnamese Knema globularia. Methods: The secondary metabolites were isolated using several chromatographic techniques. Their chemical structures were determined using nuclear magnetic resonance (NMR) spectroscopy and compared with published literature. The anti-inflammatory effect was evaluated using the Griess assay, and protein interactions were investigated through docking studies. Results: Based on their anti-inflammatory activity, six compounds (1-6) were isolated from Vietnamese K. globularia. These compounds were identified as lupeol (1), formononetin (2), isoliquiritigenin (3), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]propane-1,3-diol (4), (+)-catechin (5), and (−)-epicatechin (6). For the first time, compounds 1, 3, and 4 were reported from Vietnamese K. globularia. All isolated compounds were tested against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW264.7 cells to assess their anti-inflammatory potential. Compound 5 exhibited the highest inhibitory activity, with an IC50 value of 5.61 μM, followed by compounds 3 and 6, with IC50 values of 6.76 and 11.52 μM, respectively. However, compounds 1, 2, and 4 showed inactivity with IC50 values exceeding 30 μM. Molecular docking was then employed to investigate the affinity and interactions between compounds 3, 5, and 6 and proteins involved in inflammation, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin-8 (IL-8), along with ADMET (absorption, distribution, metabolism, excretion, and toxicity) predictions. Conclusion: These findings suggest that the active constituents derived from Vietnamese K. globularia have the potential as anti-inflammatory agents worthy of further exploration and development. [ABSTRACT FROM AUTHOR]

Objective: Aruncus dioicus has been known by the scientific literature and folk experiences for its diverse biological activities, including anti-hyperglycemic effects. Methodology: The aerial parts of the plant collected from Quan Lan Island (Vietnam) were subjected to a methodical theory-experiment investigation for its chemical composition and biological potentials. Results: Firstly, experimental isolation and spectroscopic characterization identified the compositional compounds, ie sambunigrin (1), prunasin (2), uridine (3), and adenosine (4). Secondly, their elucidated structures were predicted with promising bio-chemo-pharmacological potentiality by different computational platforms, ie: docking simulation (docking scores < 10 kcal.mol−1); quantum calculation (dipole moments < 3 Debye); QSARIS model (satisfying Lipinski's rule of five); SwissADME model (satisfying Pires’ interpretations). Finally, the compounds (1-4) were under accumulative purification and in vitro tests against diabetes-related enzymes, ie: protein tyrosine phosphatase 1B (1 with lowest IC50 value 0.39 ± 0.26 μM, 2 with no activity) and α-glucosidase (1 with lowest IC50 value 44.89 ± 0.93 μM, 2 with no activity); also, the inhibitory kinetics based on Lineweaver-Burk and Dixon plot experiments revealed the competitive inhibition mode of 1 against PTP1B (Ki value 0.49 μM). Conclusions: Altogether, the results obtained suggest that A. dioicus and its bioactive compounds, especially sambunigrin (1), uridine (3), and adenosine (4), could be considered as a natural source for further research and development of anti-diabetic agents. [ABSTRACT FROM AUTHOR]

One of the most crucial parameters in the field of machine tool engineering is the stiffness of the machine tool spindle, as it has a direct impact on the precision and accuracy of machining. This paper presents a research on the effects of geometric parameters of capillary tubes, including diameter (dc) and length (lc), on the stiffness of hydrostatic bearings in machine tools. The oil pump pressure in this study was set at a range from 3 MPa to 5 MPa. The simulation results demonstrate the relationship between the capillary geometric parameters, pressure, and the stiffness of the hydrostatic spindle unit. These findings indicate a direct relationship between stiffness and pump pressure, with increases in pressure also raising lubricant temperature, which may impair cooling. The shape of the capillary directly affects the ratio of oil chamber pressure to pump pressure, which in turn affects hardness. The results of the study indicate that for spindles in machine tools, a dc ranging from 0.3 mm to 0.6 mm and a (lc /dc) ratio of between 20 and 100 are feasible based on the given stiffness requirement. It is possible to select an appropriate set of capillary parameters to achieve the best stiffness with specific requirements under the working conditions of hydrostatic bearings based on the results of the simulation analysis. [ABSTRACT FROM AUTHOR]