20 research outputs found

    Entry of copycats of luxury brands

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    We develop a game-theoretic model to examine the entry of copycats and its implications by incorporating two salient features; these features are two product attributes, i.e., physical resemblance and product quality, and two consumer utilities, i.e., consumption utility and status utility. Our equilibrium analysis suggests that copycats with a high physical resemblance but low product quality are more likely to successfully enter the market by defying the deterrence of the incumbent. Furthermore, we show that higher quality can prevent the copycat from successfully entering the market. Finally, we show that the entry of copycats does not always improve consumer surplus and social welfare. In particular, when the quality of the copycat is sufficiently low, the loss in status utility from consumers of the incumbent product overshadows the small gain in consumption utility from buyers of the copycat, leading to an overall decrease in consumer surplus and social welfare. </jats:p

    AI is a viable alternative to high throughput screening: a 318-target study

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    : High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNetĀ® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNetĀ® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

    Current- and Voltage-Actuated Transmission Line Protection Scheme Using a Hybrid Combination of Signal Processing Techniques

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    This paper presents a current- and voltage-driven protection scheme for transmission lines based on a hybrid mix of Stockwell transform (ST) and Hilbert transform (HT). Use of both current and voltage waveforms to detect and categorize faults, improves the reliability of this protection scheme and avoids false tripping. Current and voltage waveforms captured during a period of fault are analyzed using ST to compute a median intermediate fault index (MIFI), a maximum value intermediate fault index (MVFI), and a summation intermediate fault index (SIFI). Current and voltage signals are analyzed via applying HT to compute a Hilbert fault index (HFI). The proposed hybrid current and voltage fault index (HCVFI) is obtained from the MIFI, MVFI, SIFI, and HFI. A threshold magnitude for this hybrid current and voltage fault index (HCVFITH) is set to 500 to identify the faulty phase. The HCVFIT is selected after testing the method for various conditions of different fault locations, different fault impedances, different fault occurrence angles, and reverse flows of power. Fault classification is performed using the number of faulty phases and an index for ground detection (IGD). The ground involved in a fault is detected by comparison of peak IGD magnitude with a threshold for ground detection (THGD). THGD is considered equal to 1000 in this study. The study is carried out using a two-terminal transmission line modeled in MATLAB software. The performance of the proposed technique is better compared to a discrete wavelet transform (DWT)-based technique, a timeā€“frequency approach, and an alienation method. Our algorithm effectively detected an AG fault, observed on a practical transmission line

    Three-Dimensional Carbon Monolith Coated by Nano-TiO<sub>2</sub> for Anode Enhancement in Microbial Fuel Cells

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    A three-dimensional (3D) anode is essential for high-performance microbial fuel cells (MFCs). In this study, 3D porous carbon monoliths from a wax gourd (WGCM) were obtained by freeze-drying and carbonization. Nano-TiO2 was further coated onto the surface of WGCM to obtain a nano-TiO2/WGCM anode. The WGCM anode enhanced the maximum power density of MFCs by 167.9% compared with the carbon felt anode, while nano-TiO2/WGCM anode additionally increased the value by 45.8% to achieve 1396.2 mW/m2. WGCM enhancement was due to the 3D porous structure, the good conductivity and the surface hydrophilicity, which enhanced electroactive biofilm formation and anodic electron transfer. In addition, nano-TiO2 modification enhanced the enrichment of Acinetobacter, an electricigen, by 31.0% on the anode to further improve the power production. The results demonstrated that the nano-TiO2/WGCM was an effective anode for power enhancement in MFCs

    FTH1- and SAT1-Induced Astrocytic Ferroptosis Is Involved in Alzheimer&rsquo;s Disease: Evidence from Single-Cell Transcriptomic Analysis

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    Objectives: Despite significant advances in neuroscience, the mechanisms of AD are not fully understood. Single-cell RNA sequencing (scRNA-seq) techniques provide potential solutions to analyze cellular composition of complex brain tissue and explore cellular and molecular biological mechanisms of AD. Methods: We investigated cellular heterogeneity in AD via utilization of bioinformatic analysis of scRNA-seq in AD patients and healthy controls from the Gene Expression Omnibus (GEO) database. The &ldquo;GOplot&rdquo; package was applied to explore possible biological processes in oligodendrocytes, astrocytes, and oligodendrocyte progenitor cells (OPCs). Expression patterns and biological functions of differentially expressed genes (DEGs) from scRNA-seq data were validated in RNA sequencing data. DEGs in astrocytes interacted with ferroptosis-related genes in FerrDb. CCK-8 and EdU assays were performed to measure cell proliferation ability. ROS, Fe2+ level, mitochondrial membrane potentials, iron concentrations, and total iron binding capacity (TIBC) in serum were evaluated. Y-maze and elevated maze were used to measure anxiety-like behavior. Autonomous and exploration behaviors or learning and memory ability in mice were analyzed using open field test and novel object recognition test. Results: Multiple clusters were identified, including oligodendrocytes, astrocytes, OPCs, neurons, microglia, doublets, and endothelial cells. Astrocytes were significantly decreased in AD, while oligodendrocytes and OPCs increased. Cell-to-cell ligand&ndash;receptor interaction analysis revealed that astrocytes, neurons, and OPCs mainly established contacts with other cells via the NRG3&ndash;ERBB4 ligand&ndash;receptor pair. GO and KEGG analyses found that astrocytes were enriched in the ferroptosis pathway. FTH1 and SAT1 in astrocytes were identified as hub mRNAs associated with ferroptosis. Serum iron concentration of 5xFAD mice was higher than that of WT, and emotional and cognitive function were significantly impaired as compared to WT. Serum iron concentration was negatively correlated with number of astrocytes and percentage of time spent entering the novelty arm in the Y-maze test, while it was positively correlated with percentage of time spent in the central area. Meanwhile, number of astrocytes was negatively correlated with percentage of time spent in the central area, while it was positively correlated with percentage of time spent entering the novelty arm. Conclusions: Through scRNA-seq analysis, we found that ferroptosis was activated in astrocytes and may contribute to the pathophysiological process in the entorhinal cortex. FTH1 and SAT1 were identified to impact astrocyte ferroptosis. Emotional and cognitive impairment in AD was associated with astrocyte ferroptosis. Our findings provide clues to reveal the pathophysiological processes following AD at the cellular level and highlight potential drug targets for the treatment of AD

    Loss of ACTL7A causes small head sperm by defective acrosome-acroplaxome-manchette complex

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    Abstract Background Actin-like 7Ā A (ACTL7A) is essential for acrosome formation, fertilization and early embryo development. ACTL7A variants cause acrosome detachment responsible for male infertility and early embryonic arrest. In this study, we aim to explore the additional functions of ACTL7A beyond the process of acrosome biogenesis and investigate the possible underlying mechanisms. Methods Nuclear morphology analysis was used to observe the sperm head shape of ACTL7A-mutated patients. Actl7a knock-out (KO) mouse model was generated. Immunofluorescence and transmission electron microscopy (TEM) were performed to analyze the structure of spermatids during spermiogenesis. Tandem mass tags labeling quantitative proteomics strategy was employed to explore the underlying molecular mechanisms. The expression levels of key proteins in the pathway were analyzed by western blotting. Intracytoplasmic sperm injection (ICSI)-artificial oocyte activation (AOA) technology was utilized to overcome fertilization failure in male mice with a complete knockout of Actl7a. Results The new phenotype of small head sperm associated with loss of ACTL7A in patients was discovered, and further confirmed in Actl7a-KO mice. Immunofluorescence and TEM analyses revealed that the deletion of ACTL7A damaged the formation of acrosome-acroplaxome-manchette complex, leading to abnormalities in the shaping of sperm heads. Moreover, a proteomic analysis of testes from WT and Actl7a-KO mice revealed that differentially expressed genes were notably enriched in PI3K/AKT/mTOR signaling pathway which is strongly associated with autophagy. Inhibition of autophagy via PI3K/AKT/mTOR signaling pathway activation leading to PDLIM1 accumulation might elucidate the hindered development of manchette in Actl7a-KO mice. Remarkably, AOA successfully overcame fertilization failure and allowed for the successful production of healthy offspring from the Actl7a complete knockout male mice. Conclusions Loss of ACTL7A causes small head sperm as a result of defective acrosome-acroplaxome-manchette complex via autophagy inhibition. ICSI-AOA is an effective technique to rescue male infertility resulting from ACTL7A deletion. These findings provide essential evidence for the diagnosis and treatment of patients suffering from infertility

    Genetic features of late onset primary hemophagocytic lymphohistiocytosis in adolescence or adulthood.

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    Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition of uncontrolled immune activation leading to extreme inflammation. Primary HLH was once believed to be a disease that occurred only in infancy or young children, and was rarely diagnosed in adults. It is now understood that patients can develop primary HLH in their adolescence or adulthood. This study included 252 adolescent and adult patients with a clinical diagnosis of HLH from 35 general medical institutions across mainland China. All exons and 50 bp of flanking intronic sequence of six HLH-related genes (PRF1, UNC13D, STX11, STXBP2, SH2D1A, and BIRC4) were sequenced in these patients. We identified mutations in 18/252 (7.1%) of the patients, with changes in PRF1 being most common. Late-onset HLH often features viral infection and other predisposing factors. We conclude that late-onset primary HLH is not as rare as previously thought. Older patients should not be delayed to receive HLH-related genes testing when they are suspected with HLH

    Kui Jie Tong Ameliorates Ulcerative Colitis by Regulating Gut Microbiota and NLRP3/Caspase-1 Classical Pyroptosis Signaling Pathway

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    Ulcerative colitis (UC) is one of the most refractory digestive diseases in the world. Kui jie tong (KJT) is an effective traditional Chinese medicine used clinically to treat UC. This study observed the regulatory effects of KJT on NIMA-related kinase 7- (NEK7-) activated nod-like receptor protein-3 (NLRP3)/caspase-1 classical pyroptosis pathway and intestinal flora in UC model rats. KJT components were analyzed using an ultraperformance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). A UC Sprague Dawley (SD) rat model was established using sodium dextran sulfate (DSS). Rats were randomly divided into four groups: control group (CG), UC model group (UG), KJT group (KG), and sulfasalazine (SASP) group (SG). After seven days of intervention, each groupā€™s body weight, disease activity index (DAI) scores, and colon length were recorded. Intestinal mucosal injury to each group was observed using hematoxylin-eosin staining. Additionally, we investigated the expression levels of NEK7, NLRP3, ASC, caspase-1, and GSDMD in intestinal mucosa, as well as serum interleukin- (IL-) 1Ī², IL-18, and IL-33 proinflammatory factors. Intestinal microflora was analyzed using 16s rRNA sequencing. KJT controlled weight loss; decreased DAI scores; restored colon length; improved pathological injury in the colon; inhibited NEK7, NLRP3, ASC, caspase-1, cleaved-caspase-1, GSDMD, and GSDMD-N expression; and decreased IL-1Ī², IL-18, and IL-33 contents in UG ratsā€™ serum and colon tissue (Pā€‰<0.001 or Pā€‰<0.05). KJT also increased Ruminococcaceae, unclassified_f_Ruminococcaceae, and unclassified_g_Ruminococcus_1 levels and decreased Erysipelotrichia, Erysipelotrichales, Erysipelotrichaceae, Turicibacter, and uncultured_bacterium_g_Turicibacter levels. KJT alleviated UC immune-inflammatory responses to NLRP3/caspase-1 by inhibiting the NEK-7-activated classic pyroptosis pathway and improving intestinal microflora
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