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Damping characterizes the energy dissipation capacity of materials and structures, and it is affected by several external factors such as vibrating frequency, stress history, temperature, and stress amplitude. This study investigates the relationship between the damping and the stress amplitude of environment-friendly recycled aggregate concrete (RAC). First, a function model of a member's loss factor and stress amplitude was derived based on Lazan's damping-stress function. Then, the influence of stress amplitude on the loss tangent of RAC was experimentally investigated. Finally, parameters used to determine the newly derived function were obtained by numerical fitting. It is shown that the member's loss factor is affected not only by the stress amplitude but also by factors such as the cross section shapes, boundary conditions, load types, and loading positions. The loss tangent of RAC increases with the stress amplitude, even at low stress amplitude. The damping energy exponent of RAC is not identically equal to 2.0, indicating that the damping is nonlinear. It is also found that the energy dissipation capacity of RAC is superior to that of natural aggregate concrete (NAC), and the energy dissipation capacity can be further improved by adding modified admixtures. [ABSTRACT FROM AUTHOR]

Carbonation is one of the major deteriorations that accelerate steel corrosion in reinforced concrete structures. Many mathematical/numerical models of the carbonation process, primarily diffusion-reaction models, have been established to predict the carbonation depth. However, the mass transfer of carbon dioxide in porous concrete includes molecular diffusion and convection mass transfer. In particular, the convection mass transfer induced by pressure difference is called penetration mass transfer. This paper presents the influence of penetration mass transfer on the carbonation. A penetration-reaction carbonation model was constructed and validated by accelerated test results under high pressure. Then the characteristics of wind pressure on the carbonation were investigated through finite element analysis considering steady and fluctuating wind flows. The results indicate that the wind pressure on the surface of concrete buildings results in deeper carbonation depth than that just considering the diffusion of carbon dioxide. In addition, the influence of wind pressure on carbonation tends to increase significantly with carbonation depth. [ABSTRACT FROM AUTHOR]

This study aimed to explore the impact of the Tongxinluo capsule combined with nutritional support on the clinical effi- cacy and nutritional status of patients with coronary heart disease angina pectoris. A total of 118 patients admitted to our hospital between August 2022 and May 2023 were divided into a control group and an observation group. Patients in the control group underwent routine treatment and nutritional interventions. Patients in the observation group received Tongxinluo capsules and tailored nutritional treatments. The observation group had a higher total effective rate, left ventricular ejection fraction, and high-density lipoprotein cholesterol level than the control group. Conversely, it had lower left ventricular end-systolic diameter, left ventricular end-diastolic diameter, total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels compared to the control group. Interleukin-6, tumor necrosis factor α, hypersensitive C-reactive protein levels, plasma viscosity, hematocrit, high-cut whole blood viscosity, fibrinogen level, and body mass index of the observation group were also lower than the control group. The incidence of adverse reactions between the two groups was not significant (P > 0.05). Tongxinluo capsule, combined with nutritional support effectively and safely treats coronary heart disease angina pectoris and can improve patients' cardiac function index. [ABSTRACT FROM AUTHOR]

This study was performed to assess the impact of Naoxintong capsules combined with oral nutritional supplements on cardiac function and nutritional status in patients with coronary heart disease complicated by chronic heart failure. The control group received conventional heart failure treatment, Naoxintong capsules, and diet education treatment. The experimental group, however, also received oral nutritional supplements. After treatment, the total effective rate was higher in the experimental group than in the control group. Serum terminal brain natriuretic peptide precursor, soluble ST2, and angiotensin II levels were lower in the experimental group than the control group. The left ventricular ejection fraction was higher, and the left ventricular end-systolic volume and left ventricular end-diastolic volume were lower in the experimental group than the control group. Serum albumin, prealbumin, and total protein levels were higher in the experimental group than the control group. The occurrence of adverse reactions and the Minnesota Living With Heart Failure Questionnaire score in the experimental group were lower than the control group. To sum up, Naoxintong capsules combined with oral nutritional supplements can promote cardiac function and nutritional status in patients with coronary heart disease complicated by chronic heart failure. [ABSTRACT FROM AUTHOR]

Electronic-sports (e-sports) is a form of organized, online, multiplayer video game competition, which requires both action skills and the ability and process of forming and adapting a strategy (referred to as strategization hereafter) to achieve goals. Over the past few decades, research has shown that video gaming experience has an important impact on the plasticity of the sensorimotor, attentional, and executive brain areas. However, little research has examined the relationship between e-sports experience and the plasticity of brain networks that are related to strategization. Using resting-state fMRI data and the local functional connectivity density (lFCD) analysis, this study investigated the relationship between e-sports experience (League of Legends [LOL] in this study) and brain plasticity by comparing between top-ranking LOL players and lower-ranking (yet experienced) LOL players. Results showed that the top-ranking LOL players had superior local functional integration in the executive areas compared to lower-ranking players. Furthermore, the top-ranking players had higher lFCD in the default mode areas, which have been found related to various subprocesses (e.g., memory and planning) essential for strategization. Finally, the top-ranking players' lFCD was related to their LOL expertise rank level, as indicated by a comprehensive score assigned by the gaming software based on players' gaming experience and expertise. Thus, the result showed that the local functional connectivity in central executive and default mode brain areas was enhanced in the top-ranking e-sports players, suggesting that e-sports experience is related to the plasticity of the central executive and default mode areas. [ABSTRACT FROM AUTHOR]

Common spatial pattern (CSP) is one of themost popular and effective feature extractionmethods formotor imagery-based braincomputer interface (BCI), but the inherent drawback of CSP is that the estimation of the covariance matrices is sensitive to noise. In this work, local temporal correlation (LTC) information was introduced to further improve the covariance matrices estimation (LTCCSP). Compared to the Euclidean distance used in a previous CSP variant named local temporal CSP (LTCSP), the correlation may be a more reasonable metric to measure the similarity of activated spatial patterns existing in motor imagery period.Numerical comparisons among CSP, LTCSP, and LTCCSPwere quantitatively conducted on the simulated datasets by adding outliers toDataset IVa of BCI Competition III and Dataset IIa of BCI Competition IV, respectively. Results showed that LTCCSP achieves the highest average classification accuracies in all the outliers occurrence frequencies. The application of the three methods to the EEG dataset recorded in our laboratory also demonstrated that LTCCSP achieves the highest average accuracy. The above results consistently indicate that LTCCSP would be a promising method for practical motor imagery BCI application. [ABSTRACT FROM AUTHOR]

Background: Steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) has become one of the most promising modalities for a practical noninvasive BCI system. Owing to both the limitation of refresh rate of liquid crystal display (LCD) or cathode ray tube (CRT) monitor, and the specific physiological response property that only a very small number of stimuli at certain frequencies could evoke strong SSVEPs, the available frequencies for SSVEP stimuli are limited. Therefore, it may not be enough to code multiple targets with the traditional frequencies coding protocols, which poses a big challenge for the design of a practical SSVEP-based BCI. This study aimed to provide an innovative coding method to tackle this problem. Methodology/Principal Findings: In this study, we present a novel protocol termed multiple frequencies sequential coding (MFSC) for SSVEP-based BCI. In MFSC, multiple frequencies are sequentially used in each cycle to code the targets. To fulfill the sequential coding, each cycle is divided into several coding epochs, and during each epoch, certain frequency is used. Obviously, different frequencies or the same frequency can be presented in the coding epochs, and the different epoch sequence corresponds to the different targets. To show the feasibility of MFSC, we used two frequencies to realize four targets and carried on an offline experiment. The current study shows that: 1) MFSC is feasible and efficient; 2) the performance of SSVEP-based BCI based on MFSC can be comparable to some existed systems. Conclusions/Significance: The proposed protocol could potentially implement much more targets with the limited available frequencies compared with the traditional frequencies coding protocol. The efficiency of the new protocol was confirmed by real data experiment. We propose that the SSVEP-based BCI under MFSC might be a promising choice in the future. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study.Objective: To evaluate the outcomes and safety of endoscopic laminectomy for central lumbar canal spinal stenosis.Summary Of Background Data: .: Spinal endoscopy is mostly used in the treatment of lumbar disc herniation, while endoscopic laminectomy for lumbar spinal stenosis is rarely reported.Methods: From January 2016 to June 2017, 38 patients with central lumbar canal spinal stenosis were treated with endoscopic laminectomy. Clinical symptoms were evaluated at 1, 3, 6, and 12 months and the last follow-up after surgery. Functional outcomes were assessed by using the Japanese Orthopedic Association Scores (JOA) and Oswestry Disability Index (ODI). The decompression effect was assessed by using the dural sac cross-sectional area (DSCA). Lumbar stability was evaluated using lumbar range of motion (ROM), ventral intervertebral space height (VH), and dorsal intervertebral space height (DH).Results: The mean age of the cases was 60.8 years, the mean operation time was 66.3 minutes, the blood loss was 38.8 mL, and the length of incision was 19.6 mm. The mean time in bed was 22.3 hours, and the mean hospital stay was 8.8 days. JOA scores were improved from 10.9 to 24.1 (P < 0.05), ODI scores were improved from 79.0 to 27.9 (P < 0.05), DSCA was improved from 55.7 to 109.5 mm (P < 0.05), ROM scores were improved from 5.6° to 5.7° (P < 0.05), and DH scores were reduced from 6.6 to 6.5 mm (P < 0.05). There was no significant difference in VH before and after operation (P > 0.05). There were no serious complications during the follow-ups.Conclusion: Endoscopic laminectomy had the advantage of a wider view, which was effective, safe, and less invasive for lumbar spinal stenosis.Level Of Evidence: 5. [ABSTRACT FROM AUTHOR]

Background: The aim of this retrospective study is to identify epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer patients and to compare the long-term postoperative outcomes in different EGFR-TKI-targeted therapy effects between the different EGFR mutation groups. Methods: A total of 2094 postoperative non-small cell lung cancer (NSCLC) patients with EGFR gene detection were collected in the Department of Pathology in the Cancer Hospital Chinese Academy of Medical Sciences from January 2003 to January 2014. Three hundred sixty-three patients were treated with EGFR tyrosine kinase inhibitor (TKI) after surgery: 184 harbored the exon 19 deletion mutation and 179 cases carried the exon 21 L858R point mutation. The end points included progression-free survival (PFS), overall survival (OS), and the response rate. Results: OS was increased in the EGFR exon 19 deletion group compared with the exon 21 L858R point mutation group (92 vs. 65 months; P < 0.001). But the median PFS did not differ between two groups (12 vs 14 months). The objective response rate (ORR) in 19 deletion group was increased compared with L858R mutation patients (28.35 vs. 22.73%). The disease control rate (DCR) of patients with 19 deletion benefited more from targeted therapy, compared with L858R group (93.71 vs. 84.31%, P = 0.014). In 19 deletion group, a high ORR and DCR were noted in patients treated with icotinib, 16 out of 18 achieved stable disease (SD), and the DCR in this population was 100%. Conclusions: EGFR subtypes could influence the postoperative survival of NSCLC patients with TKI-targeted therapy. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effects of cytomegalovirus (CMV) infection on the prognosis of inflammatory bowel disease (IBD). Various databases were searched using a combination of keywords associated with CMV infection and IBD. Subsequent to the selection of relevant studies in line with strict inclusion and exclusion criteria, a meta-analysis was conducted using the Stata 12.0 software. A total of 195 studies were initially retrieved, including 28 studies in Chinese and 167 in English. Following the exclusion of unsuitable studies, 7 cohort studies with 374 IBD patients were included in the meta-analysis. The results of the present study identified significant differences between patients with and without CMV infection regarding the disease duration of IBD [standardized mean difference, -0.81; 95% confidence interval (CI), -1.19 to -0.43; P<0.001], the efficacy of corticosteroid therapy [relative risk (RR), 1.24; 95% CI, 1.02-1.49; P=0.029], the colectomy rate (RR, 2.13; 95% CI, 1.03-4.40; P=0.042) and the incidence of severe IBD (RR, 1.32; 95% CI, 1.04-1.67; P=0.022). Considering the IBD onset area, patients with CMV infection may have higher susceptibility to pancolitis (RR, 1.31; 95% CI; 1.01-1.72; P=0.045); however, no difference in susceptibility to left-sided IBD was observed between patients with or without CMV infection (RR, 0.97; 95% CI, 0.72-1.30; P=0.828). In conclusion, CMV infection may be associated with the disease duration, efficacy of corticosteroid therapy, colectomy rate, severe IBD incidence and disease location of IBD; thus, the presence of CMV infection may be considered as an important biomarker for determining the prognosis of IBD. [ABSTRACT FROM AUTHOR]

Background: Severe acute respiratory syndrome (SARS) originated in China in 2002, and it spread to 26 provinces in mainland China and 32 countries across five continents in a matter of months. This outbreak resulted in 774 deaths. However, the spatial features and potential determinants of SARS input-output flows remain unclear.Methods: We used an adjusted spatial interaction model to examine the spatial effects and potential factors associated with SARS input-output flows.Results: The presence of origin-based spatial dependence positively affected SARS input-output flows from the neighbours of the origin regions. Two components of the input-output flows, migrant and hospitalization flows, exhibited distinctive features. The origin-based and destination-based spatial dependence positively affected migrant flows (i.e., due to those seeking jobs) from the neighbours of origin and destination locations. Similarly, the destination-based spatial dependence also positively affected hospitalization flows (i.e., due to those seeking treatment) from the neighbours of destination regions. However, the origin-to-destination based spatial dependence negatively affected hospitalisation flows from the neighbours of origin-to-destination regions. The direct effects accounted for 78% of the SARS input-output flows, which was 3.56-fold greater than the indirect effects. Differences in regional income drove the SARS input-output flows. Therefore, urban income had a positive effect, whereas rural income had a negative effect. Total interregional flows increased by 3.54% with a 1% increase in urban income, and intraregional flows increased by 8.35%. In contrast, the total interregional flows decreased by 3.38% with a 1% increase in rural income, and intraregional flows declined by 2.29%. Railway capacity, per person gross domestic product (PGDP), urban rate and the law of distance decay also affected the input-output flows.Conclusions: Our results confirm that the SARS input-output flows presented significant geographic spatial heterogeneity and spatial effects. Income differences were the major cause of the flows between pairs of regions. Railway capacity, PGDP, and urban rate also played important roles. These findings provide valuable information for the Chinese government to control the future spread of nationwide epidemics. [ABSTRACT FROM AUTHOR]

The neural mechanism of steady-state visual evoked potentials (SSVEP) is still not clearly understood. Especially, only certain frequency stimuli can evoke SSVEP. Our previous network study reveals that 8 Hz stimulus that can evoke strong SSVEP response shows the enhanced linkage strength between frontal and visual cortex. To further probe the directed information flow between the two cortex areas for various frequency stimuli, this paper develops a causality analysis based on the inversion of double columns model using particle swarm optimization (PSO) to characterize the directed information flow between visual and frontal cortices with the intracranial rat electroencephalograph (EEG). The estimated model parameters demonstrate that the 8 Hz stimulus shows the enhanced directional information flow from visual cortex to frontal lobe facilitates SSVEP response, which may account for the strong SSVEP response for 8 Hz stimulus. Furthermore, the similar finding is replicated by data-driven causality analysis. The inversion of neural mass model proposed in this study may be helpful to provide the new causality analysis to link the physiological model and the observed datasets in neuroscience and clinical researches. [ABSTRACT FROM AUTHOR]

To realize the efficient data capture and accurate analysis of pitting corrosion of the reinforced concrete (RC) structures, we first design and implement a wireless sensor and network (WSN) to monitor the pitting corrosion of RC panels, and then, we propose a wavelet-based algorithm to analyze the corrosion state with the corrosion data collected by the wireless platform. We design a novel pitting corrosion-detecting mote and a communication protocol such that the monitoring platform can sample the electrochemical emission signals of corrosion process with a configured period, and send these signals to a central computer for the analysis. The proposed algorithm, based on the wavelet domain analysis, returns the energy distribution of the electrochemical emission data, from which close observation and understanding can be further achieved. We also conducted test-bed experiments based on RC panels. The results verify the feasibility and efficiency of the proposed WSN system and algorithms. [ABSTRACT FROM AUTHOR]

Steady state visual evoked potentials (SSVEP) are assumed to be regulated by multiple brain areas, yet the underlying mechanisms are not well understood. In this study, we utilized multi-channel intracranial recordings together with network analysis to investigate the underlying relationships between SSVEP and brain networks in anesthetized rat. We examined the relationship between SSVEP amplitude and the network topological properties for different stimulation frequencies, the synergetic dynamic changes of the amplitude and topological properties in each rat, the network properties of the control state, and the individual difference of SSVEP network attributes existing among rats. All these aspects consistently indicate that SSVEP response is closely correlated with network properties, the reorganization of the background network plays a crucial role in SSVEP production, and the background network may provide a physiological marker for evaluating the potential of SSVEP generation [ABSTRACT FROM AUTHOR]

Abstract: The mechanical properties of electrolyte and anode represent the characteristic of anode-supported solid oxide fuel cells (SOFCs). The micro-scale film/substrate structure makes it difficult to measure the hardness and elastic modulus. In this work, a modified work of indentation method is proposed to determine the hardness and elastic modulus, and nanoindentation test is carried out for the half-cell structure of SOFCs (before and after reduction). The final large range of hardness from the proposed method is shown to be well agreement with the values determined by Oliver Pharr method. Because NiO-YSZ reduces to Ni-YSZ, the hardness of substrate is decreased by 48%, elastic modulus is decreased by 34.4%, respectively. [Copyright &y& Elsevier]

Background: The non-nucleoside reverse transcriptase inhibitor (NNRTI), as a major component of the highly active antiretroviral therapy (HAART) to HIV-1 (human immunodeficiency virus type 1) infected patients, required the development of new NNRTIs with improved resistance profile and decreased toxicity. Therefore, a series of novel compounds, 9-phenylcyclohepta[d]pyrimidinedione derivatives (PCPs), were designed based on the chemical structure of TNK-651, to detect anti-HIV-1 activity. Results: 1-[(benzyloxy)methyl]-9-phenyl-cyclohepta[d] pyrimidinedione (BmPCP) among four PCPs has antiviral activity on laboratory-adapted HIV strains (HIV-1 SF33). The results showed 50% inhibition concentrations (IC50s) of BmPCP were 0.34 μM, 1.72 μM and 1.96 μM on TZM-bl, peripheral blood mononuclear cells (PBMCs) and MT4, respectively. It was also effective against infection by the predominant HIV-1 isolates in China, with IC50s at low μM levels. Its selectivity index (SI) ranged from 67 to 266 in different cells. The results of time-of-addition assay demonstrated that BmPCP inhibited HIV-1 infection by targeting the post entry of the HIV-1 replication cycle. For inhibition of HIV-1 reverse transcriptase activity, the IC50 values of BmPCP and NVP were 1.51 and 3.67 μM, respectively. Conclusions: BmPCP with a novel structure acts as a NNRTI to inhibit HIV-1 replication and can serve as a lead compound for further development of new anti-HIV-1 drugs. [ABSTRACT FROM AUTHOR]

By a monospore isolation technique, Rhizopus sp. MK-96-1 was selected from colonies of Rhizopus sp. MK-96, which was isolated from the soil sample collected in Fujieda, Japan, and used as a parent strain. By the ammonia-concentration-gradient agar plate technique after mutation using N-methyl-N′-nitro-N-nitrosoguanidine (NTG) method, a mutant strain designated Rhizopus sp. MK-96-1196 producing more than 90 g/lL-lactic acid under pH control using liquid ammonia in an airlift bioreactor was successfully isolated. Compared with the parent strain, this mutant strain produced about twofold the amount of L-lactic acid in half fermentation time under the same culture conditions. Ammonium L-lactate was recovered and purified as free L-lactic acid via n-butyl L-lactate. The ammonia used for pH control in the fermentation broth was recovered as liquid ammonia during the recovery and purification process and subsequently reused for the next fermentation. Thus, we have developed a new highly purified L-lactic acid production process without producing recalcitrant wastes, e.g., CaSO4 (gypsum). [Copyright &y& Elsevier]