Multi-Objective Optimization of Process Parameters during Micro-Milling of Nickel-Based Alloy Inconel 718 Using Taguchi-Grey Relation Integrated Approach

This research investigates the machinability of Inconel 718 under conventional machining speeds using three different tool coatings in comparison with uncoated tool during milling operation. Cutting speed, feed rate and depth of cut were selected as variable machining parameters to analyze output responses including surface roughness, burr formation and tool wear. It was found that uncoated and AlTiN coated tools resulted in lower tool wear than nACo and TiSiN coated tools. On the other hand, TiSiN coated tools resulted in highest surface roughness and burr formation. Among the three machining parameters, feed was identified as the most influential parameter affecting burr formation. Grey relational analysis identified the most optimal experimental run with a speed of 14 m/min, feed of 1 μm/tooth, and depth of cut of 70 μm using an AlTiN coated tool. ANOVA of the regression model identified the tool coating parameter as most effective, with a contribution ratio of 41.64%, whereas cutting speed and depth of cut were found to have contribution ratios of 18.82% and 8.10%, respectively. Experimental run at response surface optimized conditions resulted in reduced surface roughness and tool wear by 18% and 20%, respectively.     

Hepatitis B among University Population: Prevalence,Associated Risk Factors,Knowledge Assessment,and Treatment Management

Background: Very few studies have been reported on hepatitis B in the State of Azad Jammu and Kashmir, Pakistan, and none of them are specific to the prevalence and causes of hepatitis B spread among educational institutes. This study aimed to estimate the prevalence of hepatitis B infection and its associated risk factors among the University of AJ and K population. Methods: An observational, cross-sectional, and analytical study was conducted with 7015 students and employees. Hepatitis B was detected by rapid immunochromatographic tests (ICTs), enzyme-linked immunosorbent assay (ELISA), and real-time quantitative PCR. A questionnaire and interview method was used to assess the disease knowledge and associated risk factors with hepatitis B through Chi-square, Fisher’s exact test, and paired t-test. Results: Of the participants, 150 (2.13%) were found positive for the hepatitis B surface antigen (57.3% male and 42.7% female). Only 0.3% participants were found fully vaccinated against the hepatitis B virus. Among ethnic groups, the Syed tribe was found more prevalent for hepatitis B infection (40.6%), while use of contaminated mourning blades (95% CI: p = 0.0001) was found as an overlooked risk factor. Hepatitis preventive awareness sessions were found to be very significant (p = 0.0001). Conclusions: The study showed that an overlooked risk factor is playing a key role in the spread of HBV in a tribe living worldwide, which must be addressed globally to eradicate hepatitis B. In Pakistan, a country-wide annual HBV vaccination program should be launched to control hepatitis B.     

Impact on emergency and elective hospital-based care in Scotland over the first 12 months of the pandemic: interrupted time-series analysis of national lockdowns

ObjectivesCOVID-19 has resulted in the greatest disruption to National Health Service (NHS) care in its over 70-year history. Building on our previous work, we assessed the ongoing impact of pandemic-related disruption on provision of emergency and elective hospital-based care across Scotland over the first year of the pandemic.DesignWe undertook interrupted time-series analyses to evaluate the impact of ongoing pandemic-related disruption on hospital NHS care provision at national level and across demographics and clinical specialties spanning the period 29 March 2020–28 March 2021.SettingScotland, UK.ParticipantsPatients receiving hospital care from NHS Scotland.Main outcome measuresWe used the percentage change of accident and emergency attendances, and emergency and planned hospital admissions during the pandemic compared to the average admission rate for equivalent weeks in 2018–2019.ResultsAs restrictions were gradually lifted in Scotland after the first lockdown, hospital-based admissions increased approaching pre-pandemic levels. Subsequent tightening of restrictions in September 2020 were associated with a change in slope of relative weekly admissions rate: –1.98% (–2.38, –1.58) in accident and emergency attendance, –1.36% (–1.68, –1.04) in emergency admissions and –2.31% (–2.95, –1.66) in planned admissions. A similar pattern was seen across sex, socioeconomic status and most age groups, except children (0–14 years) where accident and emergency attendance, and emergency admissions were persistently low over the study period.ConclusionsWe found substantial disruption to urgent and planned inpatient healthcare provision in hospitals across NHS Scotland. There is the need for urgent policy responses to address continuing unmet health needs and to ensure resilience in the context of future pandemics.     

Does a child's mid‐upper arm circumference‐for‐age z‐score represent another nutritional indicator of childhood malnutrition status?

Child wasting is defined as a weight‐for‐height/length z‐score (WLZ/WHZ) < −2, and this indicator of nutritional status is used worldwide. However, a precise measurement is required for the assessment of a child''s nutritional status, which may not always be possible due to expensive instruments, especially in poor resource settings. In some instances, mid‐upper arm circumference‐for‐age z‐score (MUACZ) is also being used for screening purposes, which is a simple and useful nutritional indicator. The objective of this paper is to identify the optimal cut‐off point for the MUACZ to identify wasted children, and also to determine if the same factors are associated with MUACZ and wasting. Data were derived from the Suchana evaluation data. The optimal cut‐off value was estimated via receiver operating characteristic (ROC) curve analysis using acute malnutrition as a gold standard with maximum sensitivity and specificity. Multiple logistic regression was used to assess the associated factors with the MUACZ. Using the gold standard indicator of nonwasting (WLZ ≥ −2), a positive outcome, the optimal cut‐off point for the MUACZ was −1.27. The area under the ROC curve was 0.88, indicating that the model had a power of 88% to differentiate between the positive and negative classes. It implies that a child''s MUACZ was correlated with WLZ, and a MUACZ below −1.27 appeared to accurately identify wasting among children aged 3–23 months. MUACZ < −1.27 might be another useful indicator of childhood wasting than a WLZ < −2.     

Enhanced pseudocapacitive energy storage and thermal stability of Sn2+ ion-intercalated molybdenum titanium carbide (Mo2TiC2) MXene

Electrochemical energy-storage (EES) devices are a major part of energy-storage systems for industrial and domestic applications. Herein, a two-dimensional (2D) transition metal carbide MXene, namely Mo₂TiC₂, was intercalated with Sn ions to study the structural, morphological, optical, and electrochemical energy-storage effects. The Sn²⁺-intercalated modified layered structure, prepared via a facile liquid-phase pre-intercalated cetyltrimethylammonium bromide (CTAB) method, showed a higher surface area of 30 m² g⁻¹, low band gap of 1.3 eV, and large interlayer spacing of 1.47 nm, as compared to the pristine Mo₂TiC₂. The Sn@Mo₂TiC₂ electrode showed a high specific capacitance of 670 F g⁻¹, representing a large diffusion control value compared to pure Mo₂TiC₂ (212 F g⁻¹) at a scan rate of 2 mV s⁻¹. The modified electrode also presented long-term cyclic performance, high-capacity retention and coulombic efficiency measured over 10 000 cycles. The Sn@Mo₂TiC₂ electrode showed much improved electrocatalytic efficiency, which may open up ways to employ double-transition 2D MXenes in energy-storage devices.

Electrochemical energy-storage (EES) devices are a major part of energy-storage systems for industrial and domestic applications.     

DABCO-promoted highly diastereo- and regioselective construction of C-3 functionalized spirooxindoles via [3 + 2] cycloaddition of 2-aryl/heteroarylidene-1H-indene-1,3(2H)-diones with N-2,2,2-trifluoroethylisatin ketimines at ambient conditions

The application of 2-aryl/heteroarylidene-1H-indene-1,3(2H)-dione as an activated olefin source in the DABCO-catalyzed [3 + 2] cycloaddition with N-2,2,2-trifluoroethylisatin ketimines has been disclosed. This highly efficient 1,3-dipolar cycloaddition reaction offered a variety of trifluoro methyl group bearing spiro-pyrrolidine linked oxindoles with four consecutive stereocentres in good to excellent yield and excellent diastereoselectivity. The synthetic practicality of the protocol was established by demonstrating the enantioselective construction of spiro-pyrrolidine-oxindoles with two vicinal spiro-quaternary chiral centres in good yield excellent enantioselectivity (>90% ee) by using ultralow loading of quinine as the catalyst at room temperature.

A highly chemo- and regioselective construction of spiropyrrolidine oxindole is devised via DABCO catalysed [3 + 2] cycloaddition reaction.     

Evaluation of multifunctional synthetic tetralone derivatives for treatment of Alzheimer's disease

Neurodegeneration, a complex disease state, comprises several pathways that contribute to cell death. Conventional approach of targeting only one of these pathways has not been proven to be entirely successful and has demanded a hypothetical change as to how researchers design and develop new drugs. In this study, effects of a series of α, β‐unsaturated carbonyl‐based tetralone derivatives against Alzheimer's disease (AD) were investigated. Moreover, their activity toward amyloid β‐induced cytotoxicity was also studied. Six compounds including 3f , 3o , 3u , 3ae , 3af , and 3ag were discovered to be most protective against Aβ‐induced neuronal cell death in PC12 cells. The findings of in vitro experiment revealed that most of these compounds exhibited potent inhibitory activity against MAO‐B, AChE, and self‐induced Aβ_1–42 aggregation. The compound 3f exhibited best AChE (IC₅₀ = 0.045 ± 0.02 μm ) inhibitory potential in addition to potent inhibition of MAO‐B (IC₅₀ = 0.88 ± 0.12 μm ). Furthermore, compound 3f disassembled the Aβ fibrils produced by self‐induced Aβ aggregation by 78.2 ± 4.8%. Collectively, these findings suggest that some compounds from this series have potential to be promising multifunctional agents for AD treatment.     

Concentration Dependent Effect of (−)‐Epicatechin on Na+/K+‐ATPase and Ca2+‐ATPase Inhibition Induced by Free Radicals in Hypertensive Patients: Comparison with L‐ascorbic Acid

Although the antioxidant properties of flavonoids are well documented, it is still unclear whether these effects are dependent on radical scavenging or iron chelating activities. Oxidative stress, a state of excessive reactive oxygen species (ROS) activity, is associated with vascular disease conditions such as hypertension. Both the anti‐ and pro‐oxidant effects of tea catechins have been implicated in the alterations of cellular functions that determine their chemoprotective and therapeutic potentials in health and diseases. The present study examined the concentration dependent (10^?7 to 10^?4 m ) effects of (?)‐epicatechin and L‐ascorbic acid on Na⁺/K⁺‐ATPase and Ca²⁺‐ATPase activity in hypertensive patients and normal subjects. L‐ascorbic acid has been used as a positive control to compare the effect of (?)‐epicatechin. A significant (p < 0.0001) decrease in the activities of Na⁺/K⁺‐ATPase and Ca²⁺‐ATPase was observed in hypertensive patients compared with normal subjects. We report that (?)‐epicatechin shows a significant (p < 0.001) dose‐dependent protective effect against oxidative stress induced by tert‐butyl hydroperoxide (t‐BHP), which is manisfested as a decrease in the activity of erythrocyte Na⁺/K⁺‐ATPase and Ca²⁺‐ATPase, in hypertensive patients as well as normal subjects. The effect of L‐ascorbic acid was also significant (p < 0.001) and was comparable with that of (?)‐epicatechin. Copyright © 2012 John Wiley & Sons, Ltd.     

A systemic route for drug loading to lymphatic phagocytes

Lymph nodes are primary germination and proliferation sites for many types of pathogens. Maintaining therapeutic levels of appropriate chemotherapeutic agents in the lymph node tissue is critical for the treatment of both infection and cancer. This study was intended to develop a systemic route for loading lymph node phagocytes with drugs, using a lymph node specific nanocarrier. The latter is assembled as a 10-15 nm particle with a drug-carrying core and a phagocyte-homing poly(1-->6)-alpha-d-glucose based interface. Biokinetics and microdistribution of the model carrier were investigated in vivo. Nanocarrier accumulation in lymph nodes reached 30-35% dose/g in central lymph nodes, with deposition in various phagocytic cell populations. The latter included cells harboring inhaled microparticles translocated to lymph nodes from the lungs. In view of the nanocarrier ability to transport and release significant amounts of various drug substances, the data suggests feasibility of systemic drug loading to lymphatic phagocytes and, through drug release, to the neighboring cells.