Loss of Katnal2 leads to ependymal ciliary hyperfunction and autism-related phenotypes in mice.

Autism spectrum disorders (ASD) frequently accompany macrocephaly, which often involves hydrocephalic enlargement of brain ventricles. Katnal2 is a microtubule-regulatory protein strongly linked to ASD, but it remains unclear whether Katnal2 knockout (KO) in mice leads to microtubule- and ASD-related molecular, synaptic, brain, and behavioral phenotypes. We found that Katnal2-KO mice display ASD-like social communication deficits and age-dependent progressive ventricular enlargements. The latter involves increased length and beating frequency of motile cilia on ependymal cells lining ventricles. Katnal2-KO hippocampal neurons surrounded by enlarged lateral ventricles show progressive synaptic deficits that correlate with ASD-like transcriptomic changes involving synaptic gene down-regulation. Importantly, early postnatal Katnal2 re-expression prevents ciliary, ventricular, and behavioral phenotypes in Katnal2-KO adults, suggesting a causal relationship and a potential treatment. Therefore, Katnal2 negatively regulates ependymal ciliary function and its deletion in mice leads to ependymal ciliary hyperfunction and hydrocephalus accompanying ASD-related behavioral, synaptic, and transcriptomic changes.

BRCA-DIRECT digital pathway for diagnostic germline genetic testing within a UK breast oncology setting: a randomised, non-inferiority trial.

BACKGROUND: Genetic testing to identify germline high-risk pathogenic variants in breast cancer susceptibility genes is increasingly part of the breast cancer diagnostic pathway. Novel patient-centred pathways may offer opportunity to expand capacity and reduce turnaround time. METHODS: We recruited 1140 women with unselected breast cancer to undergo germline genetic testing through the BRCA-DIRECT pathway (which includes a digital platform, postal saliva sampling and a genetic counsellor telephone helpline). Ahead of consenting to the test, participants were randomised to receive information about genetic testing digitally (569/1140, 49.9%) or via a pre-test genetic counselling consultation (571/1140, 50.1%). RESULTS: 1001 (87.8%) participants progressed to receive their pre-test information and consented to testing. The primary outcome, uptake of genetic testing, was higher amongst participants randomised to receive digital information compared with those randomised to a pre-test genetic counselling consultation (90.8% (95% CI: 88.5% to 93.1%) vs 84.7% (95% CI: 81.8% to 87.6%), p = 0.002, adjusted for participant age and site). Non-inferiority was observed in relation to patient knowledge, anxiety, and satisfaction. CONCLUSIONS: Findings demonstrate that standardised, digital information offers a non-inferior alternative to conventional genetic counselling, and an end-to-end patient-centred, digital pathway (supported by genetic counselling hotline) could feasibly be implemented into breast oncology settings. CLINICAL TRIAL REGISTRATION: The study is registered with, and protocol available on, ClinicalTrials.gov (NCT04842799).

Navigating the Landscape of Telemedicine Research: A Topic Modeling Approach for the Present and Future.

Introduction: Telemedicine, which is the provision of remote clinical services via telecommunication technology, has undergone an upsurge since the COVID-19 pandemic. To capture this paradigm, this study surveyed telemedicine literature, including postpandemic publications, to identify dominant research themes and temporal trends and suggest directions for future research. Methods: A corpus of 56,445 telemedicine studies is sourced from PubMed. Latent Dirichlet allocation (LDA) topic modeling performed using the Konstanz Information Miner platform. The textual data for topic modeling were processed by following standard procedures for natural language processing. Moreover, the term frequency-inverse document frequency approach was used to capture the importance of words within the corpus. We assessed perplexity, coherence, and the elbow method to determine the optimal number of topics for modeling. Results: The findings confirm the surge in telemedicine research after 2020, signifying its prominence. LDA topic modeling reveals seven distinct research themes, with the most prominent topic being "patient satisfaction" (21.38%) followed by "perspectives and challenges" (17.95%), and "smartphone apps" (14.32%). Furthermore, the results demonstrate a noticeable shift in topics from screening to therapeutic applications of telemedicine. Conclusions: This study serves as a guide for a broad range of telemedicine research topics. This synthesis of themes reflects the commitment of scholars to address the changing dynamics and health care needs, such as the COVID-19 pandemic, aging in place, smartphone usage, and technological advancement. The analysis also reveals flexible research responses to policy and contextual shifts, highlighting the collective drive to broaden the application of telemedicine in community health care.

Investigating perceptions and attitude toward telenursing among undergraduate nursing students for the future of nursing education: a cross-sectional study.

BACKGROUND: Telenursing is poised to emerge as a novel healthcare delivery system in the digital age. Hence, understanding nursing students' perspectives and readiness is pivotal for its effective implementation. This study investigated nursing students' perceptions regarding, and attitudes toward, telenursing and the factors that influenced their attitudes based on the technology acceptance model. METHODS: This study used a cross-sectional descriptive approach. The participants consisted of 188 nursing students (first to fourth year) enrolled in the College of Nursing in Korea. Differences in attitudes toward telenursing were analyzed using independent t-test and one-way analysis of variance. Pearson's correlation coefficient was used to examine the correlations between the main variables. Factors that influenced attitudes toward telenursing were analyzed using multiple regression. RESULTS: Of the participants, 65.4% lacked substantial awareness of telenursing and 19.1% had prior telenursing experience. Although prospects on telenursing indicated that 90.4% had an optimistic view, face-to-face nursing was heavily preferred for both satisfactory and favored healthcare delivery. Many cited the Internet as their source of knowledge, and only 18.6% had received telenursing education. Attitude toward telenursing was significantly more positive among those with experience of telenursing, telenursing observation in clinical practice, and telenursing education exposure. The regression model was statistically significant (F = 67.445, p < .000). Factors, such as perceived usefulness, social influence, innovativeness, and self-efficacy, influenced attitudes toward telenursing. CONCLUSIONS: Nursing students exhibited a lack of substantial awareness of telenursing; however, they simultaneously displayed a positive outlook. This lack of comprehensive understanding could stem from the absence of formal education in telenursing. Understanding and utilizing the potential of telenursing could be significantly aided by nursing students' education and knowledge. Thus, it is necessary to include telenursing education in the nursing curriculum. The skills and knowledge required for telenursing clinical practice can be developed through telenursing education. Such preparedness will affect nurses' attitudes and intentions and the quality of telenursing offered to patients in the future.

A digital pathway for genetic testing in UK NHS patients with cancer: BRCA-DIRECT randomised study internal pilot.

BACKGROUND: Germline genetic testing affords multiple opportunities for women with breast cancer, however, current UK NHS models for delivery of germline genetic testing are clinician-intensive and only a minority of breast cancer cases access testing. METHODS: We designed a rapid, digital pathway, supported by a genetics specialist hotline, for delivery of germline testing of BRCA1/BRCA2/PALB2 (BRCA-testing), integrated into routine UK NHS breast cancer care. We piloted the pathway, as part of the larger BRCA-DIRECT study, in 130 unselected patients with breast cancer and gathered preliminary data from a randomised comparison of delivery of pretest information digitally (fully digital pathway) or via telephone consultation with a genetics professional (partially digital pathway). RESULTS: Uptake of genetic testing was 98.4%, with good satisfaction reported for both the fully and partially digital pathways. Similar outcomes were observed in both arms regarding patient knowledge score and anxiety, with <5% of patients contacting the genetics specialist hotline. All progression criteria established for continuation of the study were met. CONCLUSION: Pilot data indicate preliminary demonstration of feasibility and acceptability of a fully digital pathway for BRCA-testing and support proceeding to a full powered study for evaluation of non-inferiority of the fully digital pathway, detailed quantitative assessment of outcomes and operational economic analyses. TRIAL REGISTRATION NUMBER: ISRCTN87845055.

The Molecular Mechanisms of Neuroinflammation in Alzheimer's Disease, the Consequence of Neural Cell Death.

Alzheimer's disease (AD) is accompanied by neural cell loss and memory deficit. Neural cell death, occurring via apoptosis and autophagy, is widely observed in the AD brain in addition to neuroinflammation mediated by necroptosis and the NLRP3 inflammasome. Neurotoxicity induced by amyloid-beta (Aß) and tau aggregates leads to excessive neural cell death and neuroinflammation in the AD brain. During AD progression, uncontrolled neural cell death results in the dysregulation of cellular activity and synaptic function. Apoptosis mediated by pro-apoptotic caspases, autophagy regulated by autophagy-related proteins, and necroptosis controlled by the RIPK/MLKL axis are representative of neural cell death occurred during AD. Necroptosis causes the release of cellular components, contributing to the pro-inflammatory environment in the AD brain. Inordinately high levels of neural cell death and pro-inflammatory events lead to the production of pro-inflammatory cytokines and feed-forward hyper neuroinflammation. Thus, neural cell death and neuroinflammation cause synaptic dysfunction and memory deficits in the AD brain. In this review, we briefly introduce the mechanisms of neural cell death and neuroinflammation observed in the AD brain. Combined with a typical strategy for targeting Aß and tau, regulation of neural cell death and neuroinflammation may be effective for the amelioration of AD pathologies.

Immunogenomics of Colorectal Cancer Response to Checkpoint Blockade: Analysis of the KEYNOTE 177 Trial and Validation Cohorts.

BACKGROUND & AIMS: Colorectal cancer (CRC) shows variable response to immune checkpoint blockade, which can only partially be explained by high tumor mutational burden (TMB). We conducted an integrated study of the cancer tissue and associated tumor microenvironment (TME) from patients treated with pembrolizumab (KEYNOTE 177 clinical trial) or nivolumab to dissect the cellular and molecular determinants of response to anti- programmed cell death 1 (PD1) immunotherapy. METHODS: We selected multiple regions per tumor showing variable T-cell infiltration for a total of 738 regions from 29 patients, divided into discovery and validation cohorts. We performed multiregional whole-exome and RNA sequencing of the tumor cells and integrated these with T-cell receptor sequencing, high-dimensional imaging mass cytometry, detection of programmed death-ligand 1 (PDL1) interaction in situ, multiplexed immunofluorescence, and computational spatial analysis of the TME. RESULTS: In hypermutated CRCs, response to anti-PD1 immunotherapy was not associated with TMB but with high clonality of immunogenic mutations, clonally expanded T cells, low activation of Wnt signaling, deregulation of the interferon gamma pathway, and active immune escape mechanisms. Responsive hypermutated CRCs were also rich in cytotoxic and proliferating PD1+CD8 T cells interacting with PDL1+ antigen-presenting macrophages. CONCLUSIONS: Our study clarified the limits of TMB as a predictor of response of CRC to anti-PD1 immunotherapy. It identified a population of antigen-presenting macrophages interacting with CD8 T cells that consistently segregate with response. We therefore concluded that anti-PD1 agents release the PD1-PDL1 interaction between CD8 T cells and macrophages to promote cytotoxic antitumor activity.

Quantifying prediction of pathogenicity for within-codon concordance (PM5) using 7541 functional classifications of BRCA1 and MSH2 missense variants.

PURPOSE: Conditions and thresholds applied for evidence weighting of within-codon concordance (PM5) for pathogenicity vary widely between laboratories and expert groups. Because of the sparseness of available clinical classifications, there is little evidence for variation in practice. METHODS: We used as a truthset 7541 dichotomous functional classifications of BRCA1 and MSH2, spanning 311 codons of BRCA1 and 918 codons of MSH2, generated from large-scale functional assays that have been shown to correlate excellently with clinical classifications. We assessed PM5 at 5 stringencies with incorporation of 8 in silico tools. For each analysis, we quantified a positive likelihood ratio (pLR, true positive rate/false positive rate), the predictive value of PM5-lookup in ClinVar compared with the functional truthset. RESULTS: pLR was 16.3 (10.6-24.9) for variants for which there was exactly 1 additional colocated deleterious variant on ClinVar, and the variant under examination was equally or more damaging when analyzed using BLOSUM62. pLR was 71.5 (37.8-135.3) for variants for which there were 2 or more colocated deleterious ClinVar variants, and the variant under examination was equally or more damaging than at least 1 colocated variant when analyzed using BLOSUM62. CONCLUSION: These analyses support the graded use of PM5, with potential to use it at higher evidence weighting where more stringent criteria are met.

Reclassification of clinically-detected sequence variants: Framework for genetic clinicians and clinical scientists by CanVIG-UK (Cancer Variant Interpretation Group UK).

PURPOSE: Variant classifications may change over time, driven by emergence of fresh or contradictory evidence or evolution in weighing or combination of evidence items. For variant classifications above the actionability threshold, which is classification of likely pathogenic or pathogenic, clinical actions may be irreversible, such as risk-reducing surgery or prenatal interventions. Variant reclassification up or down across the actionability threshold can therefore have significant clinical consequences. Laboratory approaches to variant reinterpretation and reclassification vary widely. METHODS: Cancer Variant Interpretation Group UK is a multidisciplinary network of clinical scientists and genetic clinicians from across the 24 Molecular Diagnostic Laboratories and Clinical Genetics Services of the United Kingdom (NHS) and Republic of Ireland. We undertook surveys, polls, and national meetings of Cancer Variant Interpretation Group UK to evaluate opinions about clinical and laboratory management regarding variant reclassification. RESULTS: We generated a consensus framework on variant reclassification applicable to cancer susceptibility genes and other clinical areas, which provides explicit recommendations for clinical and laboratory management of variant reclassification scenarios on the basis of the nature of the new evidence, the magnitude of evidence shift, and the final classification score. CONCLUSION: In this framework, clinical and laboratory resources are targeted for maximal clinical effect and minimal patient harm, as appropriate to all resource-constrained health care settings.

Quantifying evidence toward pathogenicity for rare phenotypes: The case of succinate dehydrogenase genes, SDHB and SDHD.

PURPOSE: The weight of the evidence to attach to observation of a novel rare missense variant in SDHB or SDHD in individuals with the rare neuroendocrine tumors, pheochromocytomas and paragangliomas (PCC/PGL), is uncertain. METHODS: We compared the frequency of SDHB and SDHD very rare missense variants (VRMVs) in 6328 and 5847 cases of PCC/PGL, respectively, with that of population controls to generate a pan-gene VRMV likelihood ratio (LR). Via windowing analysis, we measured regional enrichments of VRMVs to calculate the domain-specific VRMV-LR (DS-VRMV-LR). We also calculated subphenotypic LRs for variant pathogenicity for various clinical, histologic, and molecular features. RESULTS: We estimated the pan-gene VRMV-LR to be 76.2 (54.8-105.9) for SDHB and 14.8 (8.7-25.0) for SDHD. Clustering analysis revealed an SDHB enriched region (ɑɑ 177-260, P = .001) for which the DS-VRMV-LR was 127.2 (64.9-249.4) and an SDHD enriched region (ɑɑ 70-114, P = .000003) for which the DS-VRMV-LR was 33.9 (14.8-77.8). Subphenotypic LRs exceeded 6 for invasive disease (SDHB), head-and-neck disease (SDHD), multiple tumors (SDHD), family history of PCC/PGL, loss of SDHB staining on immunohistochemistry, and succinate-to-fumarate ratio >97 (SDHB, SDHD). CONCLUSION: Using methodology generalizable to other gene-phenotype dyads, the LRs relating to rarity and phenotypic specificity for a single observation in PCC/PGL of a SDHB/SDHD VRMV can afford substantial evidence toward pathogenicity.

Metabolomic analysis of amino acids and organic acids in aging mouse eyes using gas chromatography-tandem mass spectrometry.

This is a metabolomics study for monitoring altered amino acid (AA) and organic acid (OA) metabolism of in eyes from aging an mouse model at 8 and 18 weeks and 18 months. Simultaneous metabolic profiling analysis of OAs and AAs was performed as ethoxycarbonyl/methoxime/tert-butyldimethylsilyl derivatives by gas chromatography-tandem mass spectrometry. A total of 42 metabolites-24 AAs and 18 OAs-were determined and their composition values were normalized to the corresponding mean values of 8-week-old mice as the control group. Then their normalized values were plotted as star graphs, which were distorted and readily distinguishable for each age-related group. Among the 42 metabolites, 18 AAs and 11 OAs were age dependent and significantly different (p < 0.05). Principal component analysis and partial least squares discriminant analysis showed unclear separation between 8- and 18-week-old mice but clear separation between these and 18-month-old mice. In particular, the variable importance in projection scores of 4-hydroxyproline, cis-aconitic acid, glycine, isocitric acid, leucine, pipecolic acid and lysine from partial least-squares-discriminant analysis were higher than 1.3. A heatmap for the classification and visualization of 42 metabolites showed differences in metabolite changes with aging. Altered AA and OA profiles were monitored, which may explain the metabolic disturbance of AA and OA. These findings are related to mitochondrial dysfunctions related to energy metabolism and the impaired antioxidant system in the aging eye. Therefore, the present metabolomics results of the association between physiological states and altered metabolism of AA and OA will be useful for understanding the aging eye and related diseases.

Non-precious-metal catalysts for alkaline water electrolysis: operando characterizations, theoretical calculations, and recent advances.

Recent years have witnessed an upsurge in the development of non-precious catalysts (NPCs) for alkaline water electrolysis (AWE), especially with the strides made in experimental and computational techniques. In this contribution, the most recent advances in NPCs for AWE were systematically reviewed, emphasizing the application of in situ/operando experimental methods and density functional theory (DFT) calculations in their understanding and development. First, we briefly introduced the fundamentals of the anode and cathode reaction for AWE, i.e., the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), respectively. Next, the most popular in situ/operando approaches for characterizing AWE catalysts, including hard and soft XAS, ambient-pressure XPS, liquid and identical location TEM, electrochemical mass spectrometry, and Raman spectroscopy were thoroughly summarized. Subsequently, we carefully discussed the principles, computational methods, applications, and combinations of DFT with machine learning for modeling NPCs and predicting the alkaline OER and HER. With the improved understanding of the structure-property-performance relationship of NPCs for AWE, we proceeded to overview their current development, summarising state-of-the-art design strategies to boost their activity. In addition, advances in various extensively investigated NPCs for AWE were evaluated. By conveying these methods, progress, insights, and perspectives, this review will contribute to a better understanding and rational development of non-precious AWE electrocatalysts for hydrogen production.

Natural Products Targeting Amyloid Beta in Alzheimer's Disease.

Alzheimer's disease (AD) is a neurodegenerative disease characterized by severe brain damage and dementia. There are currently few therapeutics to treat this disease, and they can only temporarily alleviate some of the symptoms. The pathogenesis of AD is mainly preceded by accumulation of abnormal amyloid beta (Aß) aggregates, which are toxic to neurons. Therefore, modulation of the formation of these abnormal aggregates is strongly suggested as the most effective approach to treat AD. In particular, numerous studies on natural products associated with AD, aiming to downregulate Aß peptides and suppress the formation of abnormal Aß aggregates, thus reducing neural cell death, are being conducted. Generation of Aß peptides can be prevented by targeting the secretases involved in Aß-peptide formation (secretase-dependent). Additionally, blocking the intra- and intermolecular interactions of Aß peptides can induce conformational changes in abnormal Aß aggregates, whereby the toxicity can be ameliorated (structure-dependent). In this review, AD-associated natural products which can reduce the accumulation of Aß peptides via secretase- or structure-dependent pathways, and the current clinical trial states of these products are discussed.

Metabolomic analysis of organic acids, amino acids, and fatty acids in plasma of Hanwoo beef on a high-protein diet.

INTRODUCTION: Ketoacidosis of metabolic disease showed in beef cattle although body weight was increased by high-grain diets (HGDs). However, few studies have examined for health status related with metabolic disease of ketoacidosis following high-protein diet (HPD). OBJECTIVES: Metabolomic analysis was performed for the monitoring of health status associated with metabolic disease of ketoacidosis in the plasma of Hanwoo heifers following a HPD. METHODS: Hanwoo heifers of 24 months with 459 ± 42 kg weight were used under a 2 × 2 crossover design. The plasma was collected from control (n = 5) and HPD group (n = 5) on day 21 following diet adaptation for 20 days. Metabolic profiling analysis of organic acids (OAs), amino acids (AAs) and fatty acids (FAs) by gas chromatography-tandem mass spectrometry combined with star pattern analysis was performed in plasma. Levels of OAs, AAs and FAs were evaluated by Mann-Whitney test, PCA and PLS-DA. RESULTS: In HPD group, ketoacidosis as metabolic disease was monitored by elevated acetoacetic acid and 3-hydroxybutyric acid. In addition, the elevation of ketogenic AAs, reduction of medium chain FAs and OAs with energy metabolism in TCA cycle were monitored in HPD group. Star graphic pattern was characteristic and readily distinguished between control and HPD groups. In PLS-DA, two groups were separated with VIP score of top-ranked 10 FAs as important metabolites for discrimination. CONCLUSION: Elevation of ketone body including ketogenic AAs and reduced energy metabolism of FAs and OAs may useful for evaluation of health states associated with ketoacidosis from metabolic event by HPD in beef cattle.

Novel lineage 1 recombinants of porcine reproductive and respiratory syndrome virus isolated from vaccinated herds: genome sequences and cytokine production profiles.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a widely disseminated, macrophage-tropic arterivirus that exhibits profound genetic and pathogenic heterogeneity. The present study was conducted to determine the complete genome sequences of two novel Korean lineage 1 PRRSV-2 strains, KNU-1901 and KNU-1902, which were isolated from vaccinated pig farms experiencing unusually high morbidity and mortality. Both isolates contained notable discontinuous 423-nucleotide deletions (DELs) within the genes encoding nonstructural protein 2 (nsp2) and GP3 when compared with the prototype strain VR-2332. In particular, the nsp2 DEL viruses had unique quadripartite discontinuous DEL signatures (111-1-19-9) in nsp2; this is an expanded version of the tripartite 111-1-19 DEL previously identified in virulent lineage 1 PRRSV-2 strains. Phylogenetic analysis revealed that both novel nsp2 DEL viruses belong to the Korean clade (KOR C) of lineage 1 isolates based on ORF5 but cluster with lineage KOR A strains based on the nsp2 or complete genome sequence. Recombination detection analysis suggested that both novel isolates are recombinants and may have evolved via natural inter-lineage recombination between circulating KOR A and KOR C strains. Interestingly, compared with the prototype VR-2332 virus, the novel nsp2 DEL variants were less efficient at promoting the expression of immune response genes in porcine alveolar macrophage culture. Taken together, we conclude that KNU-1901 and KNU-1902 are recently evolved recombinant variants of the virulent lineage 1 family that caused the regional severe PRRS outbreaks.

Electrosynthesis of Dihydropyrano[4,3-b]indoles Based on a Double Oxidative [3+3] Cycloaddition.

Oxidative [3+3] cycloadditions offer an efficient route for six-membered-ring formation. This approach has been realized based on an electrochemical oxidative coupling of indoles/enamines with active methylene compounds followed by tandem 6π-electrocyclization leading to the synthesis of dihydropyrano[4,3-b]indoles and 2,3-dihydrofurans. The radical-radical cross-coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles.

Metabolomic approaches to polyamines including acetylated derivatives in lung tissue of mice with asthma.

INTRODUCTION: Recently, the relationship between polyamine (PA) metabolism and asthma has been studied in severe asthmatic therapy, but systematic PA metabolism including their acetylated derivatives was not fully understood. OBJECTIVES: Profiling analysis of polyamines (PAs) was performed to understand the biochemical events and monitor altered PA metabolism in lung tissue of mice with asthma. METHODS: Polyamine profiling of lung tissue of mice with asthma was performed without derivatization by liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with star pattern recognition analysis. The PA levels between control and asthma groups were evaluated by multivariate analysis. RESULTS: In mouse lung tissue, seven PAs were determined by LC-MS/MS in multiple reaction monitoring (MRM) mode. Their levels were normalized to the corresponding mean levels of the control group for star pattern analysis, which showed distorted heptagonal shapes with characteristic and readily distinguishable patterns for each group. Levels of putrescine (p < 0.0034), N1-acetylputrescine (p < 0.0652), and N8-acetylspermidine (p < 0.0827) were significantly increased in asthmatic lung tissue. The separation of the two groups was evaluated using multivariate analysis. In unsupervised learning, acetylated PAs including N1-acetylspermine were the main metabolites for discrimination. In supervised learning, putrescine and N1-acetylputrescine were evaluated as important metabolites. CONCLUSIONS: The present results provide basic data for understanding polyamine metabolism in asthma and may help to improve the therapy for severe asthma patients.

A Three-Step Resolution-Reconfigurable Hazardous Multi-Gas Sensor Interface for Wireless Air-Quality Monitoring Applications.

This paper presents a resolution-reconfigurable wide-range resistive sensor readout interface for wireless multi-gas monitoring applications that displays results on a smartphone. Three types of sensing resolutions were selected to minimize processing power consumption, and a dual-mode front-end structure was proposed to support the detection of a variety of hazardous gases with wide range of characteristic resistance. The readout integrated circuit (ROIC) was fabricated in a 0.18 µm CMOS process to provide three reconfigurable data conversions that correspond to a low-power resistance-to-digital converter (RDC), a 12-bit successive approximation register (SAR) analog-to-digital converter (ADC), and a 16-bit delta-sigma modulator. For functional feasibility, a wireless sensor system prototype that included in-house microelectromechanical (MEMS) sensing devices and commercial device products was manufactured and experimentally verified to detect a variety of hazardous gases.

Aged Brain Metabolomics Study by Metabolic Profiling Analysis of Amino Acids, Organic Acids, and Fatty Acids in Cortex, Cerebellum, Hypothalamus, and Hippocampus of Rats.

BACKGROUND: Aging is a progressive process characterized by weakness in brain function. Although metabolomics studies on the brain related with aging have been conducted, it is not yet fully understood. A systematic metabolomics study was performed to search for biomarkers and monitor altered metabolism in various brain tissues of the cortex, cerebellum, hypothalamus, and hippocampus of young (8 months old) and old rats (22 months old). METHODS: Simultaneous profiling analysis of amino acids (AAs), organic acids (OAs), and fatty acids (FAs) in the brain tissues of young and old rats were performed by gas chromatography-tandem mass spectrometry. RESULTS: Under optimal conditions, AA, OA, and FA profiling methods showed good linearity (r ≥0.995) with limit of detection of ≤30 and 73.2 ng and limit of quantification of ≤90.1 and 219.5 ng, respectively. Repeatability varied from 0.4 to 10.4 and 0.8 to 14.8% relative standard deviation and accuracy varied from -11.3 to 10.3 and -12.8 to 14.1% relative error, respectively. In the profiling analysis, total 32, 43, 45, and 30 metabolites were determined in cortex, cerebellum, hypothalamus, and hippocampus, respectively. In statistical analysis, eight AAs (alanine, valine, leucine, isoleucine, threonine, serine, proline, and phenylalanine) in the cortex and four metabolites (alanine, phenylalanine, 3-hydoxypropionic acid, and eicosadienoic acid) in the cerebellum were significantly evaluated (Q-value <0.05, variable importance in projection scores ≥1.0). In all brain tissues, the score plots of orthogonal partial least square discriminant analysis were clearly separated between the young and old groups. CONCLUSIONS: Metabolomics results indicate that mechanistic targets of rapamycin complex 1, branched chain-amino acid, and energy metabolism are related to inflammation and mitochondrial dysfunction in the brain during aging. Thus, these results may explain the characteristic metabolism of brain aging.

Gas Evolution Kinetics in Overlithiated Positive Electrodes and its Impact on Electrode Design.

Increasing lithium contents within the lattice of positive electrode materials is projected in pursuit of high-energy-density batteries. However, it intensifies the release of lattice oxygen and subsequent gas evolution during operations. This poses significant challenges for managing internal pressure of batteries, particularly in terms of the management of gas evolution in composite electrodes-an area that remains largely unexplored. Conventional assumptions postulate that the total gas evolution is estimated by multiplying the total particle count by the quantities of gas products from an individual particle. Contrarily, this investigation on overlithiated materials-a system known to release the lattice oxygen-demonstrates that loading densities and inter-particle spacing in electrodes significantly govern gas evolution rates, leading to distinct extents of gas formation despite of an equivalent quantity of released lattice oxygen. Remarkably, this study discoveres that O2 and CO2 evolution rates are proportional to 1O2 concentration by the factor of second and first-order, respectively. This indicates an exceptionally greater change in the evolution rate of O2 compared to CO2 depending on local 1O2 concentration. These insights pave new routes for more sophisticated approaches to manage gas evolution within high-energy-density batteries.