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This paper studies whether board connectedness affects corporate innovation. We find that well-connected boards have a positive effect on innovation activities and quality. The effect is stronger when firms have higher demand for advising or face more severe agency problems. Firms with greater needs for external finance benefit more from board connections with bankers. We show that the positive relation is causal and robust based on a battery of empirical tests including exogenous variation in board connectedness resulting from death and retirement of directors and from a regulatory shock under new exchange listing rules. Evidence indicates that types and relatedness of connections as well as director characteristics contribute to cross-sectional heterogeneity of the positive effect. This paper was accepted by Gustavo Manso, finance.

This study discusses convolutional neural networks (CNNs) for vibration signals analysis, including applications in machining surface roughness estimation, bearing faults diagnosis, and tool wear detection. The one-dimensional CNNs (1DCNN) and two-dimensional CNNs (2DCNN) are applied for regression and classification applications using different types of inputs, e.g., raw signals, and time-frequency spectra images by short time Fourier transform. In the application of regression and the estimation of machining surface roughness, the 1DCNN is utilized and the corresponding CNN structure (hyper parameters) optimization is proposed by using uniform experimental design (UED), neural network, multiple regression, and particle swarm optimization. It demonstrates the effectiveness of the proposed approach to obtain a structure with better performance. In applications of classification, bearing faults and tool wear classification are carried out by vibration signals analysis and CNN. Finally, the experimental results are shown to demonstrate the effectiveness and performance of our approach.

This paper proposes an estimation approach for tool wear and surface roughness using deep learning and sensor fusion. The one-dimensional convolutional neural network (1D-CNN) is utilized as the estimation model with X- and Y-coordinate vibration signals and sound signal fusion using sensor influence analysis. First, machining experiments with computer numerical control (CNC) parameters are designed using a uniform experimental design (UED) method to guarantee the variety of collected data. The vibration, sound, and spindle current signals are collected and labeled according to the machining parameters. To speed up the degree of tool wear, an accelerated experiment is designed, and the corresponding tool wear and surface roughness are measured. An influential sensor selection analysis is proposed to preserve the estimation accuracy and to minimize the number of sensors. After sensor selection analysis, the sensor signals with better estimation capability are selected and combined using the sensor fusion method. The proposed estimation system combined with sensor selection analysis performs well in terms of accuracy and computational effort. Finally, the proposed approach is applied for on-line monitoring of tool wear with an alarm, which demonstrates the effectiveness of our approach.

Background Age‐related muscle dysfunctions are common disorders resulting in poor quality of life in the elderly. Probiotic supplementation is a potential strategy for preventing age‐related sarcopenia as evidence suggests that probiotics can enhance muscle function via the gut–muscle axis. However, the effects and mechanisms of probiotics in age‐related sarcopenia are currently unknown. In this study, we examined the effects of Lactobacillus casei Shirota (LcS), a probiotic previously reported to improve muscle function in young adult mice. Methods We administered LcS (1 × 108 or 1 × 109 CFU/mouse/day) by oral gavage to senescence‐accelerated mouse prone‐8 mice for 12 weeks (16‐ to 28‐week‐old). Sixteen‐week‐old and 28‐week‐old SMAP8 mice were included as non‐aged and aged controls, respectively. Muscle condition was evaluated using dual‐energy X‐ray absorptiometry for muscle mass, holding impulse and grip strength tests for muscle strength, and oxygen consumption rate, gene expressions of mitochondrial biogenesis, and mitochondrial number assays for mitochondria function. Inflammatory cytokines were determined using enzyme‐linked immunosorbent assay. Gas chromatography–mass spectrometry was utilized to measure the short‐chain fatty acid levels. The gut microbiota was analysed based on the data of 16S rRNA gene sequencing of mouse stool. Results The LcS supplementation reduced age‐related declines in muscle mass (>94.6%, P < 0.04), strength (>66% in holding impulse and >96.3% in grip strength, P < 0.05), and mitochondrial function (P < 0.05). The concentration of short‐chain fatty acids (acetic, isobutyric, butyric, penic, and hexanoic acid) was recovered by LcS (>65.9% in the mice given high dose of LcS, P < 0.05) in the aged mice, and LcS attenuated age‐related increases in inflammation (P < 0.05) and reactive oxygen species (>89.4%, P < 0.001). The high dose of LcS supplementation was also associated with distinct microbiota composition as indicated by the separation of groups in the beta‐diversity analysis (P = 0.027). LcS supplementation altered predicted bacterial functions based on the gut microbiota. Apoptosis (P = 0.026), p53 signalling (P = 0.017), and non‐homologous end‐joining (P = 0.031) were significantly reduced, whereas DNA repair and recombination proteins (P = 0.043), RNA polymerase (P = 0.008), and aminoacyl‐tRNA biosynthesis (P = 0.003) were increased. Finally, the genera enriched by high‐dose LcS [linear discriminant analysis (LDA) score > 2.0] were positively correlated with healthy muscle and physiological condition (P < 0.05), while the genera enriched in aged control mice (LDA score > 2.0) were negatively associated with healthy muscle and physiological condition (P < 0.05). Conclusions Lactobacillus casei Shirota represents an active modulator that regulates the onset and progression of age‐related muscle impairment potentially via the gut–muscle axis.

The value of corporate cash holdings has increased significantly in recent decades. On average, $1 of cash is valued at $0.61 in the 1980s, $1.04 in the 1990s, and $1.12 in the 2000s. This increase is predominantly driven by the investment opportunity set and cash-flow volatility, as well as secular trends in product market competition, credit market risk, and within-firm diversification. We document a secular decrease in the speed of adjustment (SOA) in cash holdings, particularly for financially constrained firms with cash deficits, suggesting that capital market frictions can account for the trend in the value of cash holdings.

Although scholars have made significant progress in obtaining high dynamic range (HDR) images by using deep learning algorithms to fuse multiple exposure images, there are still challenges, such as image artifacts and distortion in high-brightness and low-brightness saturated areas. To this end, we propose a more detailed high dynamic range (MDHDR) method. Firstly, our proposed method uses super-resolution to enhance the details of long-exposure and short-exposure images and fuses them into medium-exposure images, respectively. Then, the HDR image is reconstructed by fusing the original medium-exposure, enhanced medium-exposure images. Extensive experimental results show that the proposed method can reconstruct good HDR images that perform better image clarity in quantitative tests and improve HDR-VDP2 by 4.8% in qualitative tests.

The COVID-19 pandemic has threatened continued access to public health services worldwide, including HIV prevention and care. This study aimed to evaluate the impact of the COVID-19 pandemic on HIV service access and delivery in the Asia region. A descriptive, cross-sectional, online study, conducted between October-November 2020, assessed the impact of COVID-19 on HIV prevention and care among people living with HIV (PLHIV), key populations (KPs), and healthcare providers (HCPs). The study populations were recruited across ten Asian countries/territories, covering Hong Kong, India, Japan, Malaysia, Philippines, Singapore, Korea, Taiwan, Thailand, and Vietnam. Across the region, 702 PLHIV, 551 KPs, and 145 HCPs were recruited. Both PLHIV and KPs reported decreased or had yet to visit hospitals/clinics (PLHIV: 35.9%; KPs: 57.5%), reduced HIV RNA viral load testing (21.9%; 47.3%), and interruptions in antiretroviral therapy (ART) (22.3%) or decreased/complete stop of HIV prevention medication consumption (40.9%). Travel constraints (40.6%), financial issues (28.9%), and not receiving prescription refills (26.9%) were common reasons for interrupted ART access, whereas reduced engagements in behaviours that could increase the risks of HIV acquisition and transmission (57.7%), travel constraints (41.8%), and less hospital/clinic visits (36.7%) underlie the disruptions in HIV preventive medications. Decreased visits from PLHIV/KPs and rescheduled appointments due to clinic closure were respectively reported by 50.7%-52.1% and 15.6%-17.0% of HCPs; 43.6%-61.9% observed decreased ART/preventive medication refills. Although 85.0% of HCPs adopted telemedicine to deliver HIV care services, 56.4%-64.1% of PLHIV/KPs were not using telehealth services. The COVID-19 pandemic substantially disrupted HIV prevention to care continuum in Asia at the time of the study. The findings highlighted differences in HIV prevention to care continuum via telehealth services utilisation by PLHIV, KPs, and HCPs. Efforts are needed to optimise infrastructure and adapt systems for continued HIV care with minimal disruptions during health emergency crises.

A question central to the Covid-19 pandemic is why the Covid-19 mortality rate varies so greatly across countries. This study aims to investigate factors associated with cross-country variation in Covid-19 mortality. Covid-19 mortality rate was calculated as number of deaths per 100 Covid-19 cases. To identify factors associated with Covid-19 mortality rate, linear regressions were applied to a cross-sectional dataset comprising 169 countries. We retrieved data from the Worldometer website, the Worldwide Governance Indicators, World Development Indicators, and Logistics Performance Indicators databases. Covid-19 mortality rate was negatively associated with Covid-19 test number per 100 people (RR = 0.92, P  = 0.001), government effectiveness score (RR = 0.96, P  = 0.017), and number of hospital beds (RR = 0.85, P  < 0.001). Covid-19 mortality rate was positively associated with proportion of population aged 65 or older (RR = 1.12, P  < 0.001) and transport infrastructure quality score (RR = 1.08, P  = 0.002). Furthermore, the negative association between Covid-19 mortality and test number was stronger among low-income countries and countries with lower government effectiveness scores, younger populations and fewer hospital beds. Predicted mortality rates were highly associated with observed mortality rates (r = 0.77; P  < 0.001). Increasing Covid-19 testing, improving government effectiveness and increasing hospital beds may have the potential to attenuate Covid-19 mortality.

As an intracellular pathogen, the reproduction of the hepatitis B virus (HBV) depends on the occupancy of host metabolism machinery. Here we test a hypothesis if HBV may govern intracellular biosynthesis to achieve a productive reproduction. To test this hypothesis, we set up an affinity purification screen for host factors that interact with large viral surface antigens (LHBS). This identified pyruvate kinase isoform M2 (PKM2), a key regulator of glucose metabolism, as a binding partner of viral surface antigens. We showed that the expression of viral LHBS affected oligomerization of PKM2 in hepatocytes, thereby increasing glucose consumption and lactate production, a phenomenon known as aerobic glycolysis. Reduction of PKM2 activity was also validated in several different models, including HBV-infected HepG2-NTCP-C4 cells, adenovirus mediated HBV gene transduction and transfection with a plasmid containing complete HBV genome on HuH-7 cells. We found the recovery of PKM2 activity in hepatocytes by chemical activators, TEPP-46 or DASA-58, reduced expressions of viral surface and core antigens. In addition, reduction of glycolysis by culturing in low-glucose condition or treatment with 2-deoxyglucose also decreased expressions of viral surface antigen, without affecting general host proteins. Finally, TEPP-46 largely suppressed proliferation of LHBS-positive cells on 3-dimensional agarose plates, but showed no effect on the traditional 2-dimensional cell culture. Taken together, these results indicate that HBV-induced metabolic switch may support its own translation in hepatocytes. In addition, aerobic glycolysis is likely essential for LHBS-mediated oncogenesis. Accordingly, restriction of glucose metabolism may be considered as a novel strategy to restrain viral protein synthesis and subsequent oncogenesis during chronic HBV infection.

Glaucoma is the most prevalent neurodegenerative disease and a leading cause of blindness worldwide. The mechanisms causing glaucomatous neurodegeneration are not fully understood. Here we show, using mice deficient in T and/or B cells and adoptive cell transfer, that transient elevation of intraocular pressure (IOP) is sufficient to induce T-cell infiltration into the retina. This T-cell infiltration leads to a prolonged phase of retinal ganglion cell degeneration that persists after IOP returns to a normal level. Heat shock proteins (HSP) are identified as target antigens of T-cell responses in glaucomatous mice and human glaucoma patients. Furthermore, retina-infiltrating T cells cross-react with human and bacterial HSPs; mice raised in the absence of commensal microflora do not develop glaucomatous T-cell responses or the associated neurodegeneration. These results provide compelling evidence that glaucomatous neurodegeneration is mediated in part by T cells that are pre-sensitized by exposure to commensal microflora. Glaucoma is a neurodegenerative disease of which the etiology is still unclear. Here the authors show that elevation of intraocular pressure induces T cell infiltration in the eyes. Furthermore, they show that T cell cross-reactivity between endogenous and commensal antigens contributes to disease onset in mice.