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Objective Cognitive frailty (CF) is associated with adverse health outcomes, but different CF models have been proposed in the literature. We explored whether cognitive impairment (CoI) assessed by the Revised Hasegawa dementia scale (HDS-R) and physical frailty (PF) assessed by the modified Frailty Phenotype can be combined to predict risks of adverse outcomes in elderly Chinese subjects. Methods The data collected in the Rugao Longevity and Aging Study were used. PF was assessed by the modified Frailty phenotype. CoI was defined as the lowest 20% of the HDS-R score. CF was defined as the co-existence of physical frailty and CoI, excluding those with severe CoI(HDR-S ≤ 10). The date and cause of death were acquired from the Death registry of Rugao's Civil Affairs Bureau. Disability was measured using the activities of daily living (ADL) scale. Results The prevalence of CF was 2.9% at baseline. During 3-year follow-up, 130 (8.1%) of the 1607 elderly subjects died. The highest mortality risk was observed among subjects with CF (hazard ratio [HR] = 2.94, 95% confidence interval [CI] = 1.28-6.78). Fully adjusted survival plots showed that CF was associated with the highest risk for 3-year mortality. The incidence of ADL disability was 6.0% after 3 years. Compared with the robust and non-CoI elderly, CF was associated with a 10.48-fold (95% CI 2.98-36.80) higher risk of ADL disability. Conclusions The CF model defined as a combination of HDS-R and Frail Phenotypes showed predictive validity for all-cause death and new-onset ADL disability 3 years later.

Background and purpose Motoric cognitive risk syndrome (MCR) is characterized by slow walking speed and subjective memory complaints (SMCs). This study investigated the prevalence and potential risk factors of MCR and its association with falls in Chinese community-dwelling older adults. Methods The analysis was based on data from the Rugao Longevity and Aging Study (RuLAS). MCR was defined as the presence of both SMCs and slow walking speed in participants free of major neurocognitive disorders. SMCs were determined according to a positive answer to the question 'Do you feel you have more problems with memory than most?' in the 15-item Geriatric Depression Scale. Slow walking speed was defined as one standard deviation or more below the mean value for patients' age and sex. Data on falls were derived from a standardized questionnaire. Results The prevalence of SMCs, slow walking speed and MCR in the RuLAS cohort (N = 1592) was 51.9%, 15.6% and 8.3%, respectively. After adjusting for other covariates, an occupation of farming (odds ratio [OR] 2.358, 95% confidence interval [CI] 1.007-5.521, p = 0.048), history of cerebrovascular disease (OR 2.215, 95% CI 1.032-4.752, p = 0.041) and hospitalization (OR 2.008, 95% CI 1.120-3.602, p = 0.019) were risk factors for MCR. Binary logistic regression analysis indicated that the risk of falls was increased by MCR (OR 1.547, 95% CI 1.009-2.371), SMC (OR 1.308, 95% CI 1.003-1.707) and slow walking speed (OR 1.442, 95% CI 1.030-2.017). Conclusions Early identification of potential risk factors of MCR can prevent the occurrence of adverse health events such as falls in the elderly.

The Guanzhong Plain of Shaanxi Province is a severely afflicted hemorrhagic fever with renal syndrome (HFRS) epidemic area, while HFRS prevalence has decreased in most epidemic areas in China. Little information is available regarding the leading fine-scale influencing factors in this highly HFRS-concentrated area and the roles of natural environmental and socioeconomic factors. To investigate this, two regions in the Guanzhong Plain, that is, the Chang'an District and Hu County, with similar geographical environments, different levels of economic development, and high epidemic prevalence, were chosen as representative areas of the HFRS epidemic.Maximum entropy models were constructed based on HFRS cases and fine-scale influencing factors, including meteorological, natural environmental, and socioeconomic factors, from 2014 to 2016.More than 95% of the HFRS cases in the study area were located in the northern plains, which has an altitude of less than 800 m, with topography contributed 84.1% of the impact on the spatial differentiation of the HFRS epidemic. In the northern plains, precipitation and population density jointly affected the spatial differentiation of the HFRS epidemic, with contribution rates of 60.7% and 28.0%, respectively. By comparing the influencing factors of the northern plains of Chang'an District and Hu County, we found that precipitation and the normalized difference vegetation index (NDVI) dominated the HFRS epidemic in the relatively developed Chang'an District, while land-use type, temperature, precipitation and population density dominated the HFRS epidemic in the relatively undeveloped Hu County.Topography was the primary key factor for HFRS prevalence in the Chang'an District and Hu County, and the spatial differentiation of HFRS was dominated by precipitation and population density in the northern plains. Compared with the influencing factors of the relatively developed Chang'an District, the developing Hu County was more affected by socioeconomic factors. When formulating targeted HFRS epidemic prevention and control strategies in the targeted areas, it is crucial to consider the local economic development state and combine natural environmental factors, including the meteorological environment and vegetation coverage.

Hydrogen storage by spillover in porous carbon material (PCM) has achieved great success in experiments. During the past 20 years, a large number of theoretical works have been performed to explore the hydrogen spillover mechanism, look for high-performance hydrogen storage materials and high-efficiency catalysts. In this paper, we summarize and analyze the results of the past researches, and draw the following conclusions: (1) In PCM surface, the stability of chemisorbed H can be reached through phase nucleation process, which can be initiated in the vicinity of surface impurities or defects. (2) To achieve the 2020 U.S. Department of Energy (DOE) target, the PCM material used for hydrogen storage by spillover should have a sp2 carbon ratio greater than 0.43 and a surface area less than 3500 m2/g, which gives us an inspiration for exploring hydrogen spillover materials. (3) Due to a high barrier, the hydrogen spillover almost can not be initiated on pure PCM substrate at room temperature. By introducing the defects or impurities (e.g. holes, carbon bridges, oxygen functional groups, boron atoms and fluorine atoms), the spillover barriers can be reduced to a reasonable range. In addition, hydrogen atoms may also migrate in a gas phase. (4) According to our previous results of kinetic Monte Carlo simulations, there is a linear relationship between the reaction temperature and the migration barrier. The optimal barrier for the hydrogen spillover should be in the range of 0.60–0.88 eV. (5) Once the hydrogen atoms are chemically adsorbed on the carbon substrate, it is difficult to diffuse again due to the strong strength of C–H bond. Several theoretical diffusion mechanisms have been proposed. For example, the H atoms in physisorption state can diffuse freely on carbon surfaces with high mobility, using the shuttle gases (e.g. BH−4, H2O, HF and NH3) to make the migration thermodynamically possible and decrease the migration barrier, the H atoms diffuse inside the interlayer space of the bi- and tetralayer graphene, and introducing the impurities on the surface to facilitate the hydrogen diffusion. (6) The H desorption through the directly recombination or the reverse spillover is unlikely to occur at normal temperature. The Eley-Rideal reaction may be the only possible mechanism for desorption of the adsorbed H atoms in carbon substrate. Finally, we have made a prospect for further research works on hydrogen storage by spillover.

Hydrogen peroxide degrades into water and oxygen, and it is generally recognized as a safe and nonaggressive disinfectant without residues or toxic chemicals, a feature especially important for its implementation in manned spacecraft. It has been extensively and safely used as a food preservative, and the use of hydrogen peroxide as a biocide in water in long-duration space missions to complement the use of iodine and silver, and in the sanitation of vegetable crops harvested in controlled ecological life support systems prior to consumption, are both proposed. Traditional detection methods for hydrogen peroxide concentrations include the iodine method or titanium salt colorimetric method, which use a variety of reagents and need cumbersome operating steps and are thus not suitable for quantitative detection applications under the microgravity environment in manned spacecraft. In order to further realize the detection of hydrogen peroxide under a microgravity environment, vacuum-introduced liquid-core waveguide Raman (LCWR) apparatus is designed and combined with a uniform design scheme. The results showed that the developed quantitative approach for hydrogen peroxide has advantages, including a standard error of calibration of 0.22, a coefficient of determination (R2) of 0.9986, and a standard error of prediction of 0.42. This study demonstrates the great potential of the apparatus for the quantitative analysis of hydrogen peroxide in water under a microgravity environment.

Chronic granulomatous disease (CGD) is the most common phagocyte defect disease. Here, we describe 114 CGD patients in our center and report a rare female infant with XL-CGD to provide a better understanding of diagnosis, treatment, and prenatal diagnosis of CGD. Patients were diagnosed by DHR-1,2,3 flow cytometry assays and gene analysis. X chromosome inactivation analysis and gp91phox protein test were used for a female infant with XL-CGD. XL-CGD accounts for the majority of cases in China and results in higher susceptibility to some infections than AR-CGD. The DHR assay can help diagnose CGD quickly, and atypical results should be combined with clinical manifestations, genetic analysis, and regular follow-up. For prenatal diagnosis, both gDNA and cDNA genotypes of amniotic fluid cells should be identified, and cord blood DHR assays should be performed to identify female XL-CGD patients.

How to reduce the H migration barrier in hydrogen spillover is one of the crucial points for hydrogen storage. In this study, we use COF-8 as a representative to study the effect of F decoration fo...

Purpose: Early diagnosis is essential for reducing liver cancer mortality, and molecular diagnosis by magnetic resonance imaging (MRI) is an emerging and promising technology. The chief aim of the present work is to use the ferritin gene, modified by the alpha-fetoprotein (AFP) promoter, carried by a highly safe vector, to produce signal contrast on T2-weighted MR imaging as an endogenous contrast agent, and to provide a highly specific target for subsequent therapy. Methods: Polyethyleneimine-β-cyclodextrin (PEI-β-CD, PC) was synthesized as a novel vector. The optimal nitrogen/phosphorus ratio (N/P) of the PC/plasmid DNA complex was determined by gel retardation, biophysical properties and transmission electron microscopy morphological analysis. The transfection efficiency was observed under a fluorescence microscope and analyzed by flow cytometry. Cellular iron accumulation caused by ferritin overexpression was verified by Prussian blue staining, and the resulting contrast imaging effect was examined by MRI. Results: The modified cationic polymer PC was much safer than high molecular weight PEI, and could condense plasmid DNA at an N/P ratio of 50 with suitable biophysical properties and a high transfection efficiency. Overexpression of ferritin enriched intracellular iron. The short-term iron imbalance initiated by AFP promoter regulation only occurred in hepatoma cells, resulting in signal contrast on MRI. The specific target TfR was also upregulated during this process. Conclusion: These results illustrate that the regulated ferritin gene carried by PC can be used as an endogenous contrast agent for MRI detection of hepatocellular carcinoma (HCC). This molecular imaging technique may promote safer early diagnosis of HCC, and provide a more highly specific target for future chemotherapy drugs.

Effective treatment for acute lung injury (ALI) is in high demand. Lung-targeted ternary nanoparticles containing anti-intercellular adhesion molecule-1 (ICAM-1) antibody-conjugated simvastatin-loaded nanostructured lipid carrier (ICAM/NLC), protamine (Pro), and angiopoietin-1 (Ang-1) gene (ICAM-NLC/Pro/Ang) were developed for ALI therapy. The ternary nanoparticles with different weight ratios of ICAM-NLC to Ang-1 gene were prepared via charge interaction. The anti-ICAM-1 antibody-conjugated ternary nanoparticles exhibited higher cellular uptake and transfection efficiency (from 26.7% to 30.9%) in human vascular endothelial cell line EAhy926 than the non-targeted control. The largest size of ICAM-NLC/Pro/Ang (357.1 nm) was employed for further study, which significantly up-regulated in vitro and in vivo Ang-1 protein expression. In vivo i.v. administration of ICAM-NLC/Pro/Ang (357.1 nm) significantly attenuated pulmonary TNF-α and IL-6 levels, inflammatory cell infiltration, and led to positive histological improvements in lipopolysaccharide-induced ALI mice. Collectively, the ICAM-NLC/Pro/Ang that co-delivered simvastatin and Ang-1 gene may represent a potential treatment modality for ALI.

The stabilizing ability of a series of promoter molecules on sH hydrogen hydrates was investigated by ab initio calculations and ab initio molecular dynamics simulations. The effect of the chemical activity of promoter molecules on the stability of the hydrogen hydrate was studied. The calculation results showed that the cohesive energy is an effective assessment indicator for the stability of the hydrate. Further, simulation results showed that the hydrogen hydrate can maintain its crystal structure for temperature ranging from 230 to 270 K, but its stability decreases with the increase of the temperature.

Objective: To analyze the molecular etiology of 92 hereditary deafness families and explore the genetic mechanism of newly identified genes in deafness heritability. Methods: We analyzed the medical history, audiology, imaging, and physical examination data of 92 probands and their family members. Probands were selected from the hereditary deafness database; they did not have any of the common genetic mutation sites. Genomic DNA was extracted from blood samples and next generation sequencing was performed on an Illumina platform, followed by co-segregation analysis of family members. The control group included the clinical data and blood samples from 207 normal hearing people. Results: Among the 92 samples, 30 homozygous variants were identified in 29 autosomal recessive hereditary deafness families, including 6 reported mutations and 26 novel mutations. Among them, MYO15A was the most frequently detected (6/92), followed by mutations in CDH23, OTOF, FGF3 (3/92 each), MYO7A, SLC26A4, MYO6 (2/92 each), BSND, CLDN14, DFNB59, ILDR1, LHFPL5, LRTOMT, TMPRSS3, TPRN, USH1C, and LOXHD1 (1/92 each). Conclusion: In patients with autosomal recessive deafness, the MYO15A, CDH23, OTOF, and FGF3 genes could be used as candidate genes for conventional genetic studies in northwest China.

Objective To expose the spectrum and frequency of GJB2, GJB3, SLC26A4 and MT-RNR1 in northwest China and to investigate the underlying causative genes in patients without common mutations. Methods We analyzed the mutation screening results of GJB2, GJB3, SLC26A4 and MT-RNR1 in 398 unrelated severe-to-profound probands with bilateral, symmetrical sensorineural hearing loss. Subsequently, we selected 10 probands with a significant family history of inherited hearing loss (HL) that did not have the above four common gene mutations to perform next-generation sequencing (NGS) of 139 known deafness genes, followed by co-segregation analysis of all available family members. Results Among the 398 patients, 69 (17.34%) had the biallelic GJB2 gene mutations, and the most common mutations were c.235delC, c.109G>A and c.299_300delAT, with allele frequencies of 12.31%, 3.38% and 3.89%, respectively. A total of 63 (15.83%) cases with biallelic SLC26A4 mutations were detected, and the most common pathogenic alleles were c.919-2A>G, c.2168A>G and c.1174A>T, with allele frequencies of 9.17%, 2.26% and 0.88%, respectively. Mitochondrial gene mutations were detected in 9 (2.26%) patients, with 5 cases of mitochondrial DNA (mtDNA) m.1555A>G mutation and 4 cases of mtDNA m.1095T>C mutation. In 10 probands with a clear family history of HL, NGS showed two novel pathogenic variants in 2 families, including c.4129C>T/c.3268C>T in LOXHD1, c.334G>A/c.2968G>T in CDH23. Sanger sequencing confirmed that these variants segregated with the HL in each family. Conclusions Our results showed that GJB2 and SLC26A4 were the two major HL-causing genes in northwest China. The most common mutation alleles in GJB2 were c.235delC, c.109G>A and c.299_300delAT, and those in SLC26A4 were c.919-2A>G, c.2168A>G and c.1174A>T. In addition, both genes and their loci can be used as the first selection of deafness gene screening. Additionally, for patients who did not have mutations of these common genes, NGS provided an efficient diagnosis for increasing known deafness genes.

The catalytic property of the bimetallic Ni/Pd, Ni/Pt and Pt/Pd particles for hydrogen spillover on penta-graphene (PG) are studied by using the first-principles and kinetic Monte Carlo (KMC) calculations. The bimetallic Ni/Pd, Ni/Pt and Pt/Pd particles can be stably decorated on PG surface with binding energies in the range of 4.15–5.52 eV. The adsorption enthalpies of H2 molecules on bimetallic particles are in the range of −11.56–−15.35 kcal/mol. The H atom can migrate from the bimetallic particles to PG with the migration barriers range from 0.67 to 0.95 eV. The KMC simulations show that the hydrogen spillover reactions can occur at a suitable temperature (260–361 K), which meet DOE target for onboard hydrogen storage systems applied to light-duty vehicles. In the study, the highest occupied molecular orbital and electric field analysis shows that the bimetal mixing can reduce the hydrogen adsorption enthalpy, and thereby reduce the H migration barrier, which displays a synergistic effect for hydrogen spillover.

Depression has been associated with chronic kidney disease (CKD). However, few studies have examined whether such association exist in average older individuals with mild to moderate reduced kidney function. This study investigated the association between reduced estimated glomerular filtration rate (eGFR) and depressive symptoms in Chinese older population. Data was obtained from the Rugao Longevity and Ageing Study conducted in Jiangsu, China. Cockcroft-Gault (CG) equation was used to calculate eGFR. Depressive symptoms were defined by using Chinese version of 15-item Geriatric Depression Scale (GDS-15). The prevalence of depressive symptoms was 9.9% among 1749 elderly participants aged 70-84 years. Many elderly had a mild to moderate reduced renal function (84.3%, 57.1% in stage2 CKD and 27.2% in stage3 CKD, respectively). The overall GDS-15 score showed an upward trend with decreasing of eGFR (p 0.05). Furthermore, a moderate decline of eGFR (in stage3 CKD) was significantly associated with increased risk of depressive symptoms even after adjusting for confounders (OR = 1.71, 95%CI 1.05-2.77, P = 0.03). Elder had no depressive symptoms if their eGFR was normal or mildly reduced. Our results suggest that a moderate decrease of eGFR (stage3 CKD) was independently associated with depressive symptoms in general Chinese elderly.

Magnesium lithospermate B (MLB) is an active polyphenol acid with multiple pharmacological activities and poor oral bioavailability. The present research aimed to construct MLB loaded solid lipid nanoparticles (MLB-SLNs) for oral delivery to enhance its bioavailability. MLB-SLNs were prepared by solvent diffusion method and subsequently modified with polyethylene glycol monostearate (PEG-SA) superficially. The particle sizes of MLB-SLNs varied from 82.57 to 53.50nm with an improved drug loading capacity (up to 16.18%) after PEG-SA modification. Pharmacokinetic study indicated that Cmax (peak plasma MLB concentration) and AUC (area under curve) of MLB-SLNs increased significantly compared to that of MLB solution in male SD rats. The relative bioavailability of MLB-SLNs with PEG-SA modification was 753.98% compared to MLB solution administered by tail intravenous injection. The enhanced transport mechanism could be further illustrated by the results that MLB-SLNs showed higher permeability across Madin-Daby canine kidney (MDCK) epithelial cell monolayer and MLB-SLNs with smaller particle size distribution and PEG-SA modification manifested stronger cellular internalization ability on MDCK cells. Thus, PEG-SA modified solid lipid nanoparticles confirmed with enhanced cellular transport and improved oral bioavailability can be a promising oral MLB delivery system.

Sustained release of thermal-instable and water-soluble drugs with low molecule weight is a challenge. In this study, sodium bicarbonate was encapsulated in ethyl cellulose microspheres by a novel solid-in-oil-in-oil (S/O/O) emulsification method using acetonitrile/soybean oil as new solvent pairs. Properties of the microspheres such as size, recovery rate, morphology, drug content, and drug release behavior were evaluated to investigate the suitable preparation techniques. In the case of that the ratio of the internal and external oil phase was 1: 9, Tween 80 as a stabilizer resulted in the highest drug content (2.68%) and a good spherical shape of microspheres. After the ratio increased to 1: 4, the microspheres using Tween 80 as the stabilizer also had high drug content (1.96%) and exhibited a sustained release behavior, with 70% of drug released within 12 h and a sustained release of more than 40 h. Otherwise, different emulsification temperatures at which acetonitrile was evaporated could influence the drug release behaviour of microspheres obtained. This novel method is a potential and effective method to achieve the encapsulation and the sustained release of thermal-instable and water-soluble drugs with low molecule weight.

Objective: To develop a physical- cognitive scale for assessment of frailty and compare the clinical features between the new scale and the conventional Fried criteria. Methods: 1757 individuals aged 70-84 were analyzed. Participants reporting three or more Fried phenotypes were grouped as frail patients (FP) whereas others as non-frail (NF). A score of Hasegawa's dementia scale (HDS-R) higher than 21.5 were classified as non-cognitive impairment group (NCI) group. By combining the cognitive and frailty criteria, participants manifesting three or more positive components out of the six were categorized into the Physical-cognitive frailty group (Pc-F) while others into non- Pc-F (Pc-NF). Results: Of all the participants, 46.7% (820) were males and 53.3% (937) were females. The mean age was 75.33 ± 3.90. 10.1% (178/1757) were evaluated as FP patients. The prevalence of CI was 53.2%; CI was much higher in the frail group (77.0%) than in the non-frail group (50.5%). Based on the new Pc-F scale, 163 out of 1579 NF participants were identified as Pc-F, and the prevalence of Pc-F reached 19.4% (341/1757). In the Pc-F group, there are more females, patients of advanced age, diabetes, stroke, CHD, CKD, metabolic syndrome, and high hs-CRP. Within the Pc-F group, patients with CI showed a higher incidence of exhaustion, low activity, weakness, and slowness than those without CI. Conclusions: Our study revealed a significantly worse status in frail participants with CI than without. Our new scale shows a stronger correlation between frailty and complications than the classic phenotype.

Anti-T-lymphocyte globulin (ATG) is frequently used in the induction regimen of renal transplantation, but its dose has not been standardized. In the present study, the efficacy of different ATG-Fresenius (ATG-F) doses was assessed in recipients of renal transplantation. A total of 131 adult recipients of renal transplantation who received ATG-F induction between August 2015 and July 2018 were included. The incidence of biopsy-confirmed acute rejection, graft function, as well as graft and patient survival within 12 months post-transplant, was assessed, and adverse events, including hematologic and infection-associated side effects, were compared between patients receiving a cumulative ATG-F dose of

The template-free ZSM-5 was prepared by hydrothermal synthesis and then modified by tetramethoxysilane (TMOS). The structure, morphology, and acidity of all samples were studied by various techniques, such as XRD, SEM, 29 Si MAS NMR, 27 Al MAS NMR, NH 3 -TPD, BET and UV-vis DRS. Comparing with the zeolites synthesized by traditional method, the template-free ZSM-5 exhibited the analogical acidity, morphology and structure, but obvious difference in acid distribution. Due to the absence of the structure directing agent, the template-free ZSM-5 possessed more acid sites situated at pore channels of catalyst and less acid sites stayed at the intersection of straight and sinusoidal channels. Consequently, the shape selectivity enhanced significantly. After TMOS modification, the non-shape acid sites located at the external surface were covered by a single SiO 2 layer. The template-free ZSM-5 achieved the highest total yield of ethylene and propylene, longest working life-span and lowest level of coke deposition among the studied catalysts, ascribing to the suppression of the side reactions.

Acute lung injury (ALI) is a critical illness without effective therapeutic modalities currently. Recent studies indicated potential efficacy of statins for ALI, while high-dose statins was suggested to be significant for attenuating inflammation in vivo. Therefore, a lung-targeted drug delivery system (DDS) delivering simvastatin (SV) for ALI therapy was developed, attempting to improve the disease with a decreased dose and minimize potential adverse effects. SV-loaded nanostructured lipid carriers (SV/NLCs) with different size were prepared primarily. With particle size increasing from 143.7 nm to 337.8 nm, SV/NLCs showed increasing drug-encapsulated efficiency from 66.70% to 91.04%. Although larger SV/NLCs exhibited slower in vitro cellular uptake by human vascular endothelial cell line EAhy926 at initial stage, while in vivo distribution demonstrated higher pulmonary accumulation of the larger ones. Thus, the largest size SV/NLCs (337.8 nm) were conjugated with intercellular adhesion molecule 1 (ICAM-1) antibody (anti-ICAM/SV/NLCs) for lung-targeted study. The anti-ICAM/SV/NLCs exhibited ideal lung-targeted characteristic in lipopolysaccharide-induced ALI mice. In vivo i.v. administration of anti-ICAM/SV/NLCs attenuated TNF-α, IL-6 and inflammatory cells infiltration more effectively than free SV or non-targeted SV/NLCs after 48-h administration. Significant histological improvements by anti-ICAM/SV/NLCs were further revealed by H&E stain. Therefore, ICAM-1 antibody-conjugated NLCs may represent a potential lung-targeted DDS contributing to ALI therapy by statins.

Ab initio calculations and molecular dynamics simulations were performed to investigate the thermodynamic and kinetic feasibility of the replacement of CH 4 from its hydrate by N 2 /CO 2 mixture. Substitution of CH 4 in small and large cages with N 2 and CO 2 has negative Gibbs free energy, whereas the substitution by CO 2 in small cages is structurally unfavorable. The calculations show that the replacement process should be the substitution with CO 2 in large cages followed by N 2 in small cages, featuring with the produce of mixed N 2 -CO 2 hydrate. Further, the simulations results indicate N 2 exhibits a faster diffusion motion than CO 2 in hydrate, implying the substitution by N 2 is more kinetically favorable to occur. Our results highlights that the replacement process should include the thermodynamically dominated CO 2 substitution simultaneous to the kinetically dominated N 2 substitution.

The replacement of N 2 with H 2 in sII clathrate hydrates was studied through ab initio calculations and molecular dynamics simulations. From the thermodynamic analysis, we suggest that the replacement is more likely to occur in the large cages than in the small cages. H 2 and N 2 can coexist in the same large cage or in the different cages, forming binary H 2 -N 2 hydrates. Simulations show that the loading capacity of H 2 can reach up to ∼4.4 wt% by the replacement method, indicating that the clathrate hydrates are a promising material for hydrogen storage under moderate conditions.

It is recognized that “the bridge-building technique remains an art”, due to unclear microscopic nature of the bridging-spillover mechanism. In this paper, a theoretical model of a carbon bridge is designed to reveal the bridging-spillover mechanism in covalent organic frameworks (COFs) by the first-principles calculations and kinetic Monte Carlo (KMC) simulations. It is found that the activation barrier of H migration from a Pt cluster to carbon bridge ranges from 0.23 to 1.05 eV, which is much lower than the direct migration from the Pt6 cluster to COF-8 (activation barrier of 2.1 eV). The bare carbon atoms on carbon bridges are mainly responsible for facilitating hydrogen spillover. KMC simulations display that H would not directly migrate from the Pt6 cluster to COF-8 unless elevating the temperature to 700 K, in contrast to that of lower temperature (88–360 K) for H migration from the Pt6 cluster to carbon bridges. In addition, the introduction of oxygen impurities can reduce the H migration barrier ...

This study investigated whether sleep duration and quality were related to life satisfaction (LS) among older Chinese adults and whether depression mediated those relationships. Cross-sectional data from the aging arm of the Rugao Longevity and Aging Study were used. Sleep duration, sleep quality, depression, LS and covariates were analyzed using logistic regressions. To assess the potential mediation of depression on the association between sleep duration and quality and LS, Aroian tests were used. Of 1756 older Chinese adults aged 70-84 years, 90.7% of the men and 83.3% of the women reported being satisfied with their lives. After adjusting for covariates, older adults who slept ≤6h per night were more likely to suffer from life dissatisfaction compared with those who slept 7-8h (OR=2.67, 95% CI 1.86-3.79), and individuals who slept poorly were almost 2 times (OR=2.91, 95% CI 2.16-3.91) more likely to have life dissatisfaction. The Aroian tests confirmed that these relationships were partially mediated by depression (p

CH 4 –CO 2 replacement technique is one promising method for both recovering CH 4 and sequestering CO 2 . To understand the replacement microscopic mechanism, we performed ab initio calculations to explore the structure and stability of singly and multiply occupied s H binary hydrate of methane and carbon dioxide. Our results show that in the singly occupied hydrate, all cages can encapsulate CO 2 molecule without changing the host lattice, and the formed binary CH 4 –CO 2 hydrates have higher stability than CH 4 hydrate. In the multiply occupied hydrate, the stability of hydrate is gradually enhanced as the number of guest molecules in 5 12 6 8 cage increases up to five. Further, when the 5 12 6 8 cage is encaged simultaneously by CH 4 and CO 2 , the binary hydrates will have the highest stability.

Many studies have proved the service life of cutter can be prolonged by electrolytic strengthening. Based on the theory of electrolytic strengthening technology, this paper introduced and developed prototype equipment for strengthening cutting edge of rotary cutter and put forward a calculation method of total electric quantity consumption during the electrolysis suitable for microcontroller. The M8 high-speed steel tap is taken as a strengthening example. After finished the strengthening process that it clearly see the results of the surface of tap was obviously polished by observing the micrograph. This equipment improves the reliability of electrolytic strengthening and the cost is relatively cheap.

Background: Laryngeal cancer stage is essential for determining the appropriate treatment strategies and evaluating prognosis for laryngeal carcinoma, which is based primarily on laryngeal cartilage invasion or not. However, there was no optimal means to confirm whether cartilage was being invaded before operation. With dual-energy CT development, it provided a new potential approach for laryngeal cartilage invasion diagnosis. Objectives: To evaluate the clinical value of dual-energy computed tomography with iodine overlay images and spectrum curve in the quantitative analysis of laryngeal cartilage invasion in patients with laryngeal carcinoma. Patients and Methods: Dual-source dual-energy CT was performed for one hundred and twenty patients with confirmed diagnosis of laryngeal carcinoma by surgical pathology (56 cases with laryngeal cartilage invasion and 64 cases without invasion). The mean CT attenuation values of laryngeal cartilage and the tumor in routine scan, arterial and venous phases was measured and cartilage invasion was considered to be present with asymmetric sclerotic changes, erosion, lysis and extralaryngeal tumor spread with iodine overlay images and routine scan images. Moreover, the sensitivity and specificity were analyzed. The slope of spectral curve and iodine concentration of the tumors, invaded laryngeal cartilage and non-invaded laryngeal cartilage were compared between arterial phase and venous phase. Furthermore, the receiver operating characteristic (ROC) curve of mean CT attenuation value, the slope of spectral curve and iodine concentration were made comparative analysis. Results: The mean CT attenuation values of the tumors, invaded laryngeal cartilage and non-invaded laryngeal cartilage had significant difference among the routine scan, arterial phase and venous phase (P < 0.05). The sign of asymmetric sclerotic changes had no significant difference between iodine overlay images and routine scan images (the same specificity and sensitivity, 77.8% and 52.6%, respectively). However, the signs of erosion, lysis and extralaryngeal tumor spread had significant difference. The specificity and sensitivity of iodine overlay images were superior to that of the routine scan images in the three signs (specificity and sensitivity of erosion: 92.3% vs. 61.5%, and 86.7% vs. 60.0%, respectively; lysis: 82.4% vs. 69.2%, and 81.8% vs. 66.7%, respectively; extralaryngeal tumor spread: 90.9% vs. 68.3%, and 100% vs. 63.5% respectively). The slope of spectral curve and iodine concentration of the tumors, invaded laryngeal cartilage and non-invaded laryngeal cartilage showed significant difference (P < 0.05). The iodine concentration of the tumor was higher than invaded laryngeal cartilage. The area under the curve (AUC) value of mean CT attenuation value in routine scan, arterial phase and venous phase were 0.064, 0.265, and 0.192, respectively. The AUC value of the slope of spectral curve in arterial phase was 0.970 and its selected cutoff was considered as 1.09. In this cutoff point, the diagnostic indices including sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 88.9%, 100%, 100%, and 82.6%, respectively, while the AUC value of the slope of spectral curve in venous phase was 0.944 and its selected cutoff was considered as 0.95. In this cutoff point, the diagnostic indices including sensitivity, specificity, PPV, NPV, positive likelihood ratio (PLR), negative likelihood ration (NLR) were 81.5%, 96.3%, 91.7%, 77.3%, 7.76, and 19.30, respectively. The AUC value of the slope of iodine concentration in arterial phase was 0.995 and its selected cutoff was considered as 1.05. In this cutoff point, the diagnostic indices including sensitivity, specificity, PPV and NPV were 92.6%, 100%, 95.8%, and 100%, respectively. Moreover, the AUC value of the slope of iodine concentration in venous phase was 0.905 and its selected cutoff was considered as 0.75. In this cutoff point, the diagnostic indices including sensitivity, specificity, PPV, NPV, PLR, and NLR were 77.8%, 88.9%, 91.3%, 82.6%, 7.00, and 24.5, respectively. Conclusion: Dual-energy CT can provided a new potential approach for laryngeal cartilage invasion diagnosis in order to guide the selection of optimal operation plan and improve the prognosis.

Influences of proteins on degradation of magnesium alloys are of great significance but not well understood. In particular the roles of amino acids, the basic unit of proteins in regulating the progress of biodegradation of magnesium based materials remain unclear. This study aims to investigate the impacts of alanine, glutamic acid and lysine on degradation of pure magnesium in phosphate buffer solution through SEM, XPS, FTIR, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and immersion tests. The changed contents of amino acids in solutions were detected by UV-vis spectrophotometer. Results demonstrate that the charges of the selected amino acids imposed significant contribution to suppressing the degradation of pure magnesium in phosphate buffer solution. The presence of amino acids led to the formation of phosphate-based corrosion products, increasing free corrosion potential, and reduction in corrosion current density and solution pH depending on their isoelectric points and molecular structures. A plausible corrosion mechanism organised by amino acids on pure magnesium was proposed.

This paper briefly describes the principle of the ultrasonic single point incremental forming of the sheet metal. In which we established the finite element model and finished the finite simulation with ABAQUS. According to the simulation result, we analyzed the influence law of vibration frequency of the axis on the distribution of the stress and strain of the sheet metal, the thickness, and the axial force in the process of ultrasonic single point incremental forming of the sheet metal. The result shows that the influence on the stress and thickness of the sheet metal is minimal, and the influence on the strain follows the law of cosines in which the strain is minimum when the vibration frequency is equal to 15kHZ.The influence on the axial force is that when the frequency is f=0kHz～40kHz the axial force decreases with the increase of the frequency. However, the axial force increased dramatically with the increase of the frequency when the frequency is above 40kHz.

Using first-principles calculations, we have investigated electronic properties of germanene superlattices. Though bandgap can be obtained in all the superlattices by sublattice equivalence breaking, it could only be opened in some inversion symmetry preserved superlattices with Γ as four-fold degenerate Dirac point. The D 6h antidot, though it does not harm the inversion symmetry, can still open bandgap by perturbing the four-fold degeneracy. Furthermore, the bandgap opened by either the sublattice equivalence breaking or the four-fold degeneracy perturbation could be continuously narrowed through reducing the defect density in germanene. These results are interesting to call for further theoretical and experimental studies.