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Electrocatalytic CO2 reduction reaction (CO2RR) conducted in a flow‐based device exhibits a substantial enhancement in Faradaic efficiency and catalytic current density compared to a conventional H‐type configuration. This highlights the distinct catalytic environment and behavior inherent in flow cells as opposed to H cells. To investigate the authentic properties of a catalyst within a flow‐based device, customized flow cells have been specifically devised for operando techniques during CO2RR and CORR, rather than resorting to an in‐situ three‐electrode H‐type configuration with its disparate catalytic environment and performance. This approach ensures a catalytic environment identical to that employed in electrochemical measurements. This review delineates the disparities between H‐type and flow‐based cells as well as the operando techniques tailored for flow‐based devices, including X‐ray absorption spectroscopy and Raman spectroscopy, preserving a consistent catalytic environment. It also compiles recent findings on copper‐based systems using operando flow‐based devices. The operando insights reveal a significant augmentation in catalytic current density, impacting both chemical properties and crystal structures. Furthermore, the observation of various catalytic intermediates enriches our comprehension. In essence, the application of operando techniques to flow‐based devices furnishes a comprehensive understanding of the catalytic behavior exhibited by diverse systems, propelling progress toward achieving Net Zero emissions. [ABSTRACT FROM AUTHOR]

Developing ruthenium‐based heterogeneous catalysts with an efficient and stable interface is essential for enhanced acidic oxygen evolution reaction (OER). Herein, we report a defect‐rich ultrathin boron nitride nanosheet support with relatively independent electron donor and acceptor sites, which serves as an electron reservoir and receiving station for RuO2, realizing the rapid supply and reception of electrons. Through precisely controlling the reaction interface, a low OER overpotential of only 180 mV (at 10 mA cm−2) and long‐term operational stability (350 h) are achieved, suggesting potential practical applications. In situ characterization and theoretical calculations have validated the existence of a localized electronic recycling between RuO2 and ultrathin BN nanosheets (BNNS). The electron‐rich Ru sites accelerate the adsorption of water molecules and the dissociation of intermediates, while the interconnection between the O‐terminal and B‐terminal edge establishes electronic back‐donation, effectively suppressing the over‐oxidation of lattice oxygen. This study provides a new perspective for constructing a stable and highly active catalytic interface. [ABSTRACT FROM AUTHOR]

Developing ruthenium‐based heterogeneous catalysts with an efficient and stable interface is essential for enhanced acidic oxygen evolution reaction (OER). Herein, we report a defect‐rich ultrathin boron nitride nanosheet support with relatively independent electron donor and acceptor sites, which serves as an electron reservoir and receiving station for RuO2, realizing the rapid supply and reception of electrons. Through precisely controlling the reaction interface, a low OER overpotential of only 180 mV (at 10 mA cm−2) and long‐term operational stability (350 h) are achieved, suggesting potential practical applications. In situ characterization and theoretical calculations have validated the existence of a localized electronic recycling between RuO2 and ultrathin BN nanosheets (BNNS). The electron‐rich Ru sites accelerate the adsorption of water molecules and the dissociation of intermediates, while the interconnection between the O‐terminal and B‐terminal edge establishes electronic back‐donation, effectively suppressing the over‐oxidation of lattice oxygen. This study provides a new perspective for constructing a stable and highly active catalytic interface. [ABSTRACT FROM AUTHOR]

Background and aims: Fatty liver disease (FLD) is associated with several metabolic derangements. We conducted a retrospective cross-sectional and longitudinal study to evaluate the role of FL severity in the risk of new-onset and co-existing hypertension (HTN) and diabetes mellitus (DM). Methods: The cross-sectional cohort consisted of 41,888 adults who received health checkups in a tertiary hospital of Taiwan from 1999 to 2013. Of them, 34,865 without HTN and/or DM at baseline and within 1 year after enrollment were included as a longitudinal cohort (mean, 6.45 years for HTN; 6.75 years for DM). FL severity based on the degree of hepatic steatosis was assessed by ultrasound sonography. Results: In cross-sectional cohort, 22,852 (54.6%) subjects had FL (18,203 [43.46%] mild FL and 4,649 [11.10%] moderate/severe FL); 13.5% (n = 5668) had HTN; and 3.4% (n = 1411) had DM. Moderate/severe FL and mild FL had significantly higher risks of existing HTN (adjusted odds ratio/95% confidence interval [CI] 1.59/1.43–1.77 and 1.22/1.13–1.32, respectively). In longitudinal cohort, 3,209 and 822 subjects developed new-onset HTN and DM, respectively (annual incidence, 14.3 and 3.5 per 1000 person-years; 10-year cumulative incidence, 14.35% and 3.89%, respectively). Moderate/severe and mild FL had significantly higher risks of new-onset HTN (adjusted hazard ratio [aHR]/CI 1.54/1.34–1.77 and 1.26/1.16–1.37, respectively) and DM (aHR/CI 5.88/4.44–7.81 and 3.22/2.56–4.07, respectively). Resolved FL during follow-up decreased the risk of HTN and/or DM. Conclusions: Patients with FL are at high risk of prevalent and incident HTN and/or DM. The risk increases with the severity of FL. [ABSTRACT FROM AUTHOR]

The increasing demand over the higher density and smaller form factor of memory packages have become a mainstream due to the boom of artificial intelligence and 5G/6G. While form factor of memory packages moves toward smaller and thinner geometry with higher pin counts, the package overall thermal–mechanical behavior is one of a key concern due to the harsh environment of field usage. In the paper, solder joint reliability test is conducted to understand the thermal–mechanical performance between the direct chip-attach (DCA) and fan-out chip scale package (FOCSP). It is observed the overall reliability of DCA package performs better than FOCSP, which is likely because of coefficient of thermal expansion (CTE) mismatch. Inside the FOCSP structure, the results indicate that higher Cu stud height and thinner base die thickness would contribute to better reliability performance. In failure analysis, the failure modes of signal and power net inside FOCSP packages occur either at Cu RDL (Redistribution Layers) crack or IMC (Interface Metallic Compound)/solder crack. In terms of DCA package, the signal net is likely to occur slight electrical short, and the power net exhibit the IMC/solder crack near package side. In addition, the thermal interface analysis of warpage behavior between PCB and package has been studied to correlate with the solder joint reliability performance inside FOCSP case. In thermal warpage analysis of DCA package and board, when under colling stage profile, the package sits at center location exhibit more thermal stress then the edge one, shifting JFFS warpage from negative to positive value, and thus lead to earlier failure. Last, the study will list out a table to discuss the pros and cons of DCA and FOCSP package in terms of reliability, cost, and signal integrity perspective. [ABSTRACT FROM AUTHOR]

The controlled attenuation parameter (CAP) measurement obtained from FibroScan® is a low-risk method of assessing fatty liver. This study investigated the association between the FibroScan® CAP values and nine anthropometric indicators, including the abdominal volume index (AVI), body fat percentage (BFP), body mass index (BMI), conicity index (CI), ponderal index (PI), relative fat mass (RFM), waist circumference (WC), waist–hip ratio (WHR), and waist-to-height ratio (WHtR), and risk of non-alcoholic fatty liver disease (fatty liver). We analyzed the medical records of adult patients who had FibroScan® CAP results. CAP values <238 dB/m were coded as 0 (non- fatty liver) and ≥238 dB/m as 1 (fatty liver). An individual is considered to have class 1 obesity when their body mass index (BMI) ranges from 30 kg/m2 to 34.9 kg/m2. Class 2 obesity is defined by a BMI ranging from 35 kg/m2 to 39.9 kg/m2, while class 3 obesity is designated by a BMI of 40 kg/m2 or higher. Out of 1763 subjects, 908 (51.5%) had fatty liver. The BMI, WHtR, and PI were found to be more strongly correlated with the CAP by the cluster dendrogram with correlation coefficients of 0.58, 0.54, and 0.54, respectively (all p < 0.0001). We found that 28.3% of the individuals without obesity had fatty liver, and 28.2% of the individuals with obesity did not have fatty liver. The BMI, CI, and PI were significant predictors of fatty liver. The BMI, PI, and WHtR demonstrated better predictive ability, indicated by AUC values of 0.72, 0.68, and 0.68, respectively, a finding that was echoed in our cluster group analysis that showed interconnected clustering with the CAP. Therefore, of the nine anthropometric indicators we studied, the BMI, CI, PI, and WHtR were found to be more effective in predicting the CAP score, i.e., fatty liver. [ABSTRACT FROM AUTHOR]

Gender equality laws and gender mainstreaming policies are transforming police forces that once were exclusively male. However, images of police masculinity and male-centered bravery persist at both public and institutional levels, frequently marginalizing female officers in the process. Beginning with the assumption that effective police work requires far more than simple physical-force masculinity, this study investigates the structural practices that form and consolidate ideological links between that masculinity and police work. The findings suggests that police work definitions tend to prioritize physical force and attack capacity, thereby constructing a gender category-linked hierarchy of wu-wen strategies. The resulting systemic political and social orders justify the presumption that men are more suited to police work, thereby bolstering the above-mentioned ideological links. To achieve gender inclusivity, the masculinity cult in policing must be reexamined, mechanisms that value force must be dismantled, and job definitions must be expanded to incorporate more diverse policing practices. [ABSTRACT FROM AUTHOR]

Breast cancer is now the most frequently diagnosed malignancy, and metastasis remains the leading cause of death in breast cancer. However, little is known about the dynamic changes during the evolvement of dissemination. In this study, 65 968 cells from four patients with breast cancer and paired metastatic axillary lymph nodes are profiled using single‐cell RNA sequencing (scRNA‐seq) and spatial transcriptomics. A disseminated cancer cell cluster with high levels of oxidative phosphorylation (OXPHOS), including the upregulation of cytochrome C oxidase subunit 6C and dehydrogenase/reductase 2, is identified. The transition between glycolysis and OXPHOS when dissemination initiates is noticed. Furthermore, this distinct cell cluster is distributed along the tumor's leading edge. The findings here are verified in three different cohorts of breast cancer patients and an external scRNA‐seq dataset, which includes eight patients with breast cancer and paired metastatic axillary lymph nodes. This work describes the dynamic metabolic evolvement of early disseminated breast cancer and reveals a switch between glycolysis and OXPHOS in breast cancer cells as the early event during lymph node metastasis. [ABSTRACT FROM AUTHOR]

After the mass vaccination project in Taiwan, the prevalence of the hepatitis B virus (HBV) infection for the college-aged population of 18 to 21 years is uncertain. We aimed to investigate the prevalence of hepatitis B markers in different birth cohorts. A total of 38,075 students in universities in Kaohsiung area undergoing entrance examinations between July 2006 to September 2020 were included. Seroprevalence of the hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) status and laboratory data were collected. The seropositive rate of HBsAg was less than 1% for students born after 1991. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST), were significantly higher, and body mass index (BMI) was significantly lower in HBV carriers compared to those who were not carriers (all p < 0.001). Multivariate logistic regression showed that age, male, higher BMI, and positive HBsAg were risk factors of abnormal ALT value. A decrease in the positive rate of anti-HBs which was significantly higher in the cohort of plasma-derived vaccines than recombinant vaccines was found. We concluded that there were decreasing trends in seropositive rates of HBsAg and anti-HBs for students of the college-aged population in the Kaohsiung area. The status of HBsAg was a predictive factor of abnormal ALT levels. The period effect on anti-HBs seropositivity for DNA recombinant vaccine somehow existed. [ABSTRACT FROM AUTHOR]

Bi-manual therapy (BT), mirror therapy (MT), and robot-assisted rehabilitation have been conducted in hand training in a wide range of stages in stroke patients; however, the mechanisms of action during training remain unclear. In the present study, participants performed hand tasks under different intervention conditions to study bilateral sensorimotor cortical communication, and EEG was recorded. A multifactorial design of the experiment was used with the factors of manipulating objects (O), robot-assisted bimanual training (RT), and MT. The sum of spectral coherence was applied to analyze the C3 and C4 signals to measure the level of bilateral corticocortical communication. We included stroke patients with onset <6 months (n = 6), between 6 months and 1 year (n = 14), and onset >1 year (n = 20), and their Brunnstrom recovery stage ranged from 2 to 4. The results showed that stroke duration might influence the effects of hand rehabilitation in bilateral cortical corticocortical communication with significant main effects under different conditions in the alpha and beta bands. Therefore, stroke duration may influence the effects of hand rehabilitation on interhemispheric coherence. [ABSTRACT FROM AUTHOR]

Copy number alterations (CNAs) are pivotal genetic events in triple-negative breast cancer (TNBC). Here, our integrated copy number and transcriptome analysis of 302 TNBC patients reveals that gene alpha-endosulfine (ENSA) exhibits recurrent amplification at the 1q21.3 region and is highly expressed in TNBC. ENSA promotes tumor growth and indicates poor patient survival in TNBC. Mechanistically, we identify ENSA as an essential regulator of cholesterol biosynthesis in TNBC that upregulates the expression of sterol regulatory element-binding transcription factor 2 (SREBP2), a pivotal transcription factor in cholesterol biosynthesis. We confirm that ENSA can increase the level of p-STAT3 (Tyr705) and activated STAT3 binds to the promoter of SREBP2 to promote its transcription. Furthermore, we reveal the efficacy of STAT3 inhibitor Stattic in TNBC with high ENSA expression. In conclusion, the amplification of ENSA at the 1q21.3 region promotes TNBC progression and indicates sensitivity to STAT3 inhibitors. Copy number alterations are pivotal genetic events in triple-negative breast cancer. Here the authors show the amplification of ENSA at the 1q21.3 region promotes the progression of TNBC via up-regulation of cholesterol biosynthesis. [ABSTRACT FROM AUTHOR]

What is known and objectives: Augmented renal clearance (ARC) is characterized by enhanced renal clearance, which leads to insufficient vancomycin exposure and treatment failure. In haematologic malignancy patients, determination of optimal vancomycin dosage is essential because of high stake of life‐threatening bacterial infection and increased clearance. The aim of this study was to describe vancomycin pharmacokinetic parameters in haematologic malignancy with augmented renal clearance children and define the appropriate dosing regimen to achieve an AUC0‐24h/MIC ≥400. Methods: Hematologic malignancy with ARC children was enrolled in this retrospective study. The vancomycin PPK model was established by non‐linear mixed‐effects modelling programme. Goodness‐of‐fit (GOF) plots, non‐parametric bootstrap, normalized prediction distribution error (NPDE) and visual predictive checks (VPCs) were carried out for internal evaluation of the final model. Monte Carlo simulation method was used to stimulate the optimal dosage regimens. Results: Fifty‐three patients with 106 samples were included. A one‐compartment model with first‐order elimination was developed, and the final model was as follows: CL (L/h) = 6.32×（WT/70）0.75 × e0.0467; V(L) = 39.6×(WT/70), where WT denotes weight (kg). The internal validation of the model showed a good prediction performance. Monte Carlo simulation results showed that when MIC was 0.5 mg/L or 1 mg/L, the recommended doses to achieve a target of AUC0‐24h/MIC ≥400 were 25 to 40 and 50 to 75 mg/kg/d, respectively. With decreasing weight, the recommended dosage to achieve an AUC0‐24h/MIC ≥400 increased. What is new and conclusion: A one‐compartment vancomycin PPK model was established in haematologic malignancy with augmented renal clearance children with weight with allometric scaling as a significant covariate. When MIC was 1 mg/L, current recommended paediatric dosages were insufficient in haematologic malignancy with augmented renal clearance children and should be increased. [ABSTRACT FROM AUTHOR]

Immune response and immunotherapy play important roles in triple-negative breast cancer (TNBC). However, it is difficult to judge whether cancer is "immune-inactivated" or "immune-activated" by the carcinoma itself. The immune reaction of the microenvironment or the host to the tumor might be more informative. We assumed that clinically enlarged but pathologically negative regional lymph nodes served as an indicator for early immune response to tumors. First, we identified women with pN0 breast cancer disease from the current Surveillance, Epidemiology, and End Results database, and we compared the cN1 patients of breast cancer-specific survival (BCSS) with cN0 patients. Then, we extracted total RNA from 36 paired large (defined as minimum diameter more than 15 mm in size) and small lymph nodes (defined as maximum diameter less than 5 mm in size) from 12 TNBC, 12 HER2-enriched, and 12 luminal-like patients and performed RNA sequencing to explore the gene expression and cellular landscape of large nodes compared to small ones. Among 692 women with pathologically confirmed node-negative disease, cN1 patients unexpectedly had a better BCSS compared with cN0 in TNBC (adjusted hazard ratio 0.148, 95% CI, 0.040–0.546, P = 0.004) but not in other subtypes. Further transcriptome sequencing of 12 paired enlarged and small negative nodes from TNBC patients revealed that increased immune activation signaling (e.g., interferon-gamma response pathways) and abundant immune cells (activated dendritic cells, CD4+ and CD8+ T-cells) were more frequently observed in enlarged nodes. Our data implied that early immune activation in regional lymph nodes in TNBC might affect survival. [ABSTRACT FROM AUTHOR]

Several γ-glutamyl compounds are known to have favorable features for a variety of biotechnological and pharmaceutical applications. However, so far only a limited number of γ-glutamyl compounds have been synthesized through γ-glutamyltranspeptidase (GGT). With the help of thin layer chromatography and computer-assisted image analysis techniques, we performed an enzymatic method involving Bacillus licheniformis GGT (BlGGT) for the synthesis of γ-glutamyl-L-leucine (γ-Glu- Leu). The optimum conditions for a biocatalytic synthesis of γ- Glu-Leu were determined to be 200 mM glutamine, 200 mM leucine, 50 mM Tris-HCl buffer (pH 9.0), and BlGGT at a working concentration of 2.0 U/mL. Upon a 5-h incubation of the reaction mixture at 50°C, the product yield could reach approximately 52%. The preparative synthesis of γ-Glu-Leu by BlGGT was done under optimal conditions at millimol scale level. The reaction products were subjected to mass spectrometry/nuclear magnetic resonance analyses to ensure the successful synthesis of γ-Glu-Leu. Taken together, the present study demonstrates the high potentiality of BlGGT-catalyzed reaction in the synthesis of γ-glutamyl compounds. [ABSTRACT FROM AUTHOR]

Background: Critical value reporting has been widely adopted by hospitals throughout the world, but there were few reports about neonatal critical values. This study aimed to analyze characteristics of the neonatal critical values considered at our center and to provide information on improving neonatal intensive care. Methods: A retrospective study of critical values at a newborn tertiary center in China was conducted to assess neonatal critical values according to test, distribution, reporting time, patient outcome and the impact to the therapy. Results: In total, 926 critical values were recorded. Overall, 66.52% (616/926) of the items were reported within 24 hours of admission, 50.28% (465/926) during duty times and 54.75% (507/926) in the neonatal intensive care unit (NICU). The routine coagulation test was the most frequent source of critical values. Electrocardiography, blood gas analysis and therapeutic drug monitoring of drug levels were associated with the highest rates of treatment intervention (100%); routine coagulation tests were the lowest (23.14%). Sample quality was the main cause of false-positive critical values. Conclusions: The incidence of neonatal critical values peaked during the first 24 hours post-admission and during duty periods. Each newborn center needs to enact rapid treatment guidelines to address common critical values in order to facilitate clinical interventions. Periodically reviewing critical values could help to optimize clinical practices. [ABSTRACT FROM AUTHOR]

The passivation effect of atomic layer deposition of (ALD) AlO film on a HgCdTe infrared detector was investigated in this work. The passivation effect of AlO film was evaluated by measuring the minority carrier lifetime, capacitance versus voltage ( C- V) characteristics of metal-insulator-semiconductor devices, and resistance versus voltage ( R- V) characteristics of variable-area photodiodes. The minority carrier lifetime, C- V characteristics, and R- V characteristics of HgCdTe devices passivated by ALD AlO film was comparable to those of HgCdTe devices passivated by e-beam evaporation of ZnS/CdTe film. However, the baking stability of devices passivated by AlO film is inferior to that of devices passivated by ZnS/CdTe film. In future work, by optimizing the ALD AlO film growing process and annealing conditions, it may be feasible to achieve both excellent electrical properties and good baking stability. [ABSTRACT FROM AUTHOR]

The optoelectronic performance of the mid-wavelength HgCdTe infrared focal plane array (IRFPA) with refractive microlenses integrated on its CdZnTe substrate has been numerically simulated. A reduced light-distribution model based on scalar Kirchhoff diffraction theory was adopted to reveal the true behavior of IRFPAs operating in an optical system under imaging conditions. The pixel crosstalk obtained and the energy-gathering characteristics demonstrated that the microlenses can delay the rise in crosstalk when the image point shifts toward pixel boundaries, and can restrict the major optical absorption process in any case within a narrow region around the pixel center. The dependence of the microlenses' effects on the system's properties was also analyzed; this showed that intermediate relative aperture and small microlens radius are required for optimized device performance. Simulation results also indicated that for detectors farther from the center of the field of view, the efficacy of microlenses in crosstalk suppression and energy gathering is still maintained, except for a negligible difference in the lateral magnification from an ordinary array without microlenses. [ABSTRACT FROM AUTHOR]

Recent studies have shown the evocation of lateral spread response (LSR) due to the compression of the facial nerve in hemifacial spasm (HFS). Intraoperative monitoring (IOM) of LSR could help locate neurovascular conflicts and confirm adequate micro-vascular decompression (MVD) while treatment of hemifacial spasm (HFS). However, studies on early LSR loss before decompression in HFS surgery are sparse, indicating the need to understand various perceptions on it. Therefore, we retrospectively analyzed 50 adult HFS patients who underwent MVD during the period of September 2018–June 2021. We employed IOM combining traditional LSR (tLSR) and dual LSR (dLSR). One patient was excluded owing to the lack of LSR induction throughout the surgery, while 49 were divided into groups A (n = 14) and B (n = 35), designated as with or without early LSR loss groups, respectively, and offending vessels were analyzed. The mean age of group A patients was significantly younger (47.8 ± 8.6) than that of group B (53.9 ± 10.6) (p = 0.0393). The significant predominating offending vessel in group A was the anterior inferior cerebellar artery (AICA, 78.57%). However, group B included those with AICA (28.57%), posterior inferior cerebellar artery (PICA, 22.86%), vertebral artery (VA) involved (25.71%), and combined AICA and PICA (22.86%). Group B exhibited poorer clinical outcomes with more complications. Conclusively, early LSR loss might occur in the younger population, possibly due to the AICA offending vessel. The compression severity of offending vessels may determine the occurrence of early LSR loss. [ABSTRACT FROM AUTHOR]

Objective Target-controlled infusion (TCI) of propofol is an effective way of delivering propofol during endoscopy. However, the ideal effect-site concentration ( Ce) of propofol has not yet been defined in an Asian population. This study aimed to determine the ideal Ce of propofol in painless gastrointestinal endoscopy in a Taiwanese population. Methods A total of 121 consecutive patients undergoing diagnostic endoscopy were recruited for this study. The endoscopic procedure was carried out within 1 h. TCI of propofol was utilized during the procedure. All patients received the same regimen to induce conscious sedation, including a bolus of midazolam (0.04 mg/kg) and fentanyl (0.5 μg/kg). The Ce of propofol was calculated using the Schneider model. Patients were randomly assigned to either the low Ce group (1.5-2.5 μg/mL) or high Ce group (3.0-4.0 μg/m L). Their cardiovascular and respiratory events were monitored during the procedure and the patients' post-procedure satisfaction was evaluated. Results The mean requirement for propofol was 232.02 mg in the low Ce group and 329.56 mg in the high Ce group, respectively ( P < 0.0001). No unexpected event was observed in either group. However, more episodes of hypotension were observed in the high Ce group ( P = 0.026). The post-procedure satisfaction rate between the two groups was comparable. Conclusion A low Ce of propofol TCI (1.5-2.5 μg/m L) achieved adequate anesthesia, reduced the risk of hypotension, and attained a high satisfaction rate in a Taiwanese population undergoing diagnostic painless endoscopy. [ABSTRACT FROM AUTHOR]

Abstract: The role of glutamate 398 in the autocatalytic processing of Bacillus licheniformis γ-glutamyltranspeptidase (BlGGT) was explored by site-directed mutagenesis. This glutamate was substituted by either alanine, aspartate, arginine or glutamine and the expressed mutant enzymes were purified to apparent homogeneity with metal-affinity chromatography. SDS–PAGE analysis showed that E398A, E398D and E398K were unable to process themselves into a large and a small subunit. However, E398Q was not only able to process itself, but also had a catalytic activity comparable to that of BlGGT. As compared with the wild-type enzyme, no significant change in circular dichroism spectra was observed for the mutant proteins. Thermal unfolding of BlGGT, E398A, E398D, E398K and E398Q followed the two-state unfolding process with a transition point (T m) of 47.7–69.4 °C. Tryptophan fluorescence spectra of the mutant enzymes were different from the wild-type protein in terms of fluorescence intensity. Native BlGGT started to unfold beyond ∼1.92 M guanidine hydrochloride (GdnHCl) and reached an unfolded intermediate, [GdnHCl]0.5, N–U, at 3.07 M equivalent to free energy change () of 14.53 kcal/mol for the N → U process, whereas the denaturation midpoints for the mutant enzymes were 1.31–2.99 M equivalent to of 3.29–12.05 kcal/mol. Taken together, these results strongly suggest that the explored glutamate residue is indeed important for the autocatalytic processing of BlGGT. [Copyright &y& Elsevier]

Heavy metals, including arsenic and lead, may lead to cellular oxidative damage that is linked to hypertension. Manganese superoxide dismutase (MnSOD) is a scavenger of reactive oxygen species, and 8-oxoguanine DNA glycosylase (OGG1) is the major glycosylase that repairs DNA lesions. Interestingly, whether there is an elevated risk of hypertension with arsenic or lead exposure in individuals with genetic variations in MnSOD or OGG1 has not yet been investigated. Questionnaires were administered to 240 Taiwanese rural residents. Blood pressure and biochemical indicators were assessed in each subject. Urinary levels of arsenic and lead were measured with atomic absorption spectrometry; and MnSOD and OGG1 genotypes were identified via polymerase chain reaction. There was a dose-response relationship between urinary arsenic levels and risk of hypertension ( P = 0.021, test for trend). However, there was no association between urinary lead levels and hypertension risk. Individuals with high urinary arsenic levels and the MnSOD Val- Ala/Ala- Ala genotypes had a greater risk of hypertension than those with low urinary arsenic levels and the MnSOD Val- Val genotype (odds ratio [OR] = 4.2, 95% confidence interval [CI] = 1.7-10.3). Subjects with a high urinary arsenic level and the OGG1 Cys- Cys genotype also had a greater risk of hypertension than those with a low urinary arsenic level and the OGG1 Ser- Ser/Ser- Cys genotypes (OR = 3.4, 95% CI = 1.1-10.7). Thus, both MnSOD and OGG1 genotypes may be prone to an increased risk of hypertension associated with arsenic exposure. [ABSTRACT FROM AUTHOR]

The role of glutamate 398 in the autocatalytic processing of Bacillus licheniformis γ‐glutamyltranspeptidase (BlGGT) was explored by site‐directed mutagenesis. This glutamate was substituted by either alanine, aspartate, arginine or glutamine and the expressed mutant enzymes were purified to apparent homogeneity with metal‐affinity chromatography. SDS–PAGE analysis showed that E398A, E398D and E398K were unable to process themselves into a large and a small subunit. However, E398Q was not only able to process itself, but also had a catalytic activity comparable to that of BlGGT. As compared with the wild‐type enzyme, no significant change in circular dichroism spectra was observed for the mutant proteins. Thermal unfolding of BlGGT, E398A, E398D, E398K and E398Q followed the two‐state unfolding process with a transition point (T m) of 47.7–69.4 °C. Tryptophan fluorescence spectra of the mutant enzymes were different from the wild‐type protein in terms of fluorescence intensity. Native BlGGT started to unfold beyond ∼1.92 M guanidine hydrochloride (GdnHCl) and reached an unfolded intermediate, [GdnHCl]0.5, N–U, at 3.07 M equivalent to free energy change ( Δ ⁢ G N − U H 2 ⁢ O ) of 14.53 kcal/mol for the N → U process, whereas the denaturation midpoints for the mutant enzymes were 1.31–2.99 M equivalent to Δ ⁢ G N − U H 2 ⁢ O of 3.29–12.05 kcal/mol. Taken together, these results strongly suggest that the explored glutamate residue is indeed important for the autocatalytic processing of BlGGT. [ABSTRACT FROM AUTHOR]

Qianlabeo striatus gen. et sp. nov. is described from a stream tributary to the Beipan Jiang of the upper Zhu Jiang (Pearl River) drainage in Matou, Anshun County, Guizhou Province, China. This monotypic genus is mainly characterized by its oromadibular morphology, namely an upper lip only present in and fully adnate to the side of the upper jaw, not covered by the pendulous rostral fold; the median portion of the upper jaw lacking an upper lip but bearing a thin, flexible and cornified cutting edge that is fully covered by the pendulous rostral fold; a postlabial groove prolonged, extended anteromedially close to the anteromost point of the midline of the lower lip but not to meet with its counterpart. The type species of this genus, Q. striatus has a longitudinal dark stripe along the side of the body. [ABSTRACT FROM AUTHOR]

Placocheilus is re-diagnosed on the basis of oromandibular structures compared to those of closely related groups. It is represented in China by three species restricted to Yunnan, namely P. caudofasciatus from the Tengtiaohe River (Nam Na), P. cryptonemus from the Nujiang Rive (upper Salween River basin), and P. robustus, herein described as a new species from the Yuanjiang River (Red River basin). P. robustus n. sp. is differentiated from its congeners in having a stout caudal peduncle (depth 72.4-82.5% of its length) and the medium-sized scaleless midventral region of belly extended slightly beyond halfway from the pectoral- to pelvic-fin origin. It is further distinguished from P. caudofasciatus in having a coarsely crenulated rostral fold with 18-23 indentations on its distal margin and a smaller mental adhesive disc (length 66.7-71.4% of its width and 37.0-43.1% of the head length). [ABSTRACT FROM AUTHOR]

The effect of substrate surface roughness on the wettability of Sn-Bi solders is investigated by the eutectic Sn-Bi alloy on Cu/Al2O3 substrates at 190 °C. To engineer the surface with different roughnesses, the Cu-side of the substrates is polished with sandpaper with abrasive number 100, 240, 400, 600, 800, 1200, and 1 μm alumina powder, respectively. Both dynamic and static contact angles of the solder drops are studied by the real-time image in a dynamic contact angle analyzer system (FTA200). During dynamic wetting, the wetting velocity of the solder drop decreases for the rougher surface. However, the time to reach the static contact angle seems to be identical with different substrate surface roughness. The wetting tip of the solder cap exhibits a waveform on the rough surface, indicating that the liquid drop tends to flow along the valley. As the solder drops reach a static state, the static contact angle increases with the substrate surface roughness. This demonstrates that the wettability of solders degrades as the substrates become rough. [ABSTRACT FROM AUTHOR]

Korea initiated a new experiment, called a dynamic response system for open democratic societies as a principle to respond to the novel coronavirus (COVID-19). The global pandemic of COVID-19 led to a surge in demand for healthcare medical masks and respirators, and strained the global supply chain of mask production and distribution systems. This study provides a systemic view of critical personal protective equipment for both healthcare staff and the public to stop the spread of COVID-19. This study investigates the dynamic response system of healthcare mask production to the coronavirus and discusses lessons learned in view of systems thinking. The study shows that it is critical to developing a quick and dynamic response system to the evolving market conditions with flexible and agile operations. Visibility with transparency with information sharing with the public is also critical under global pandemic. Due to the shortage of mask supply, smart consumption is required along with collaboration with public and private sectors, as well as global organizations. Democratic leadership and a well-prepared strategic plan for long-term period are essential to the open society to prepare the global pandemic in the future. This study serves as a benchmark for dynamic and timely responses to the global pandemic. [ABSTRACT FROM AUTHOR]

A highly conserved 458PLSSMXP464 sequence in the small subunit (S-subunit) of an industrially important Bacillus licheniformis γ-glutamyltranspeptidase (BlGGT) was identified by sequence alignment. Molecular structures of the precursor mimic and the mature form of BlGGT clearly reveal that this peptide sequence is in close spatial proximity to the self-processing and catalytic sites of the enzyme. To probe the role of this conserved sequence, ten mutant enzymes of BlGGT were created through a series of deletion and alanine-scanning mutagenesis. SDS-PAGE and densitometric analyses showed that the intrinsic ability of BlGGT to undergo autocatalytic processing was detrimentally affected by the deletion-associated mutations. However, loss of self-activating capacity was not obviously observed in most of the Ala-replacement mutants. The Ala-replacement mutants had a specific activity comparable to or greater than that of the wild-type enzyme; conversely, all deletion mutants completely lost their enzymatic activity. As compared with BlGGT, S460A and S461S showed greatly enhanced kcat/Km values by 2.73- and 2.67-fold, respectively. The intrinsic tryptophan fluorescence and circular dichroism spectral profiles of Ala-replacement and deletion mutants were typically similar to those of BlGGT. However, heat and guanidine hydrochloride-induced unfolding transitions of the deletion-associated mutant proteins were severely reduced as compared with the wild-type enzyme. The predictive mutant models suggest that the microenvironments required for both self-activation and catalytic reaction of BlGGT can be altered upon mutations. [ABSTRACT FROM AUTHOR]