Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the environment.Among these measurement methods,the closed-loop method is frequently used.However,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation chamber.The CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and visually.In this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the chamber.The consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was verified.The effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were investigated.Based on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion effect.The CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

Management of regional citrate anticoagulation for continuous renal replacement therapy:guideline recommendations from Chinese emergency medical doctor consensus

Continuous renal replacement therapy(CRRT)is widely used for treating critically-ill patients in the emergency department in China.Anticoagulant therapy is needed to prevent clotting in the extracorporeal circulation during CRRT.Regional citrate anticoagulation(RCA)has been shown to potentially be safer and more effective,and is now recommended as the preferred anticoagulant method for CRRT.However,there is still a lack of unified standards for RCA management in the world,and there are many problems in using this method in clinical practice.The Emergency Medical Doctor Branch of the Chinese Medical Doctor Association(CMDA)organized a panel of domestic emergency medicine experts and international experts of CRRT to discuss RCA-related issues,including the advantages and disadvantages of RCA in CRRT anticoagulation,the principle of RCA,parameter settings for RCA,monitoring of RCA(mainly metabolic acid-base disorders),and special issues during RCA.Based on the latest available research evidence as well as the paneled experts'clinical experience,considering the generalizability,suitability,and potential resource utilization,while also balancing clinical advantages and disadvantages,a total of 16 guideline recommendations were formed from the experts'consensus.

Expert consensus on the diagnosis and treatment of heat stroke in China

Heat stroke(HS)is a fatal disease caused by thermal damage in the body,and it has a very high mortality rate.In 2015,the People’s Liberation Army Professional Committee of Critical Care Medicine published the first expert consensus on HS in China,Expert consensus on standardized diagnosis and treatment for heat stroke.With an increased understanding of HS and new issues that emerged during the HS treatment in China in recent years,the 2015 consensus no longer meet the requirements for HS prevention and treatment.It is necessary to update the consensus to include the latest research evidence and establish a new consensus that has broader coverage,is more practical and is more in line with China’s national conditions.This new expert consensus includes new concept of HS,recommendations for laboratory tests and auxiliary examinations,new understanding of diagnosis and differential diagnosis,On-site emergency treatment and In-hospital treatment,translocation of HS patients and prevention of HS.

Photocatalytic performance of TiO_2 nanocrystals with/without oxygen defects

To investigate the role of oxygen defects on the photocatalytic activity of TiO2,the TiO2 nanocrystals with/without oxygen defects are successfully synthesized by the hydrothermal and sol‐gel methods,respectively.The as‐prepared TiO2 nanocrystals with defects are light blue and the absorption edge of light is towards the visible light region(~420 nm).Raman and X‐ray photoelectron spectroscopy(XPS)measurements all confirm that the concentration of oxygen vacancies in the TiO2 synthesized by the sol‐gel method is less than that synthesized through the hydrothermal route.The introduction of oxygen defects contributes to a new state in the band gap that narrows the band gap,which is the reason for the extension of light absorption into the visible light region.The photocurrent results confirm that this band‐gap narrowing enhances the photocurrent response under simulated solar light irradiation.The TiO2 with oxygen defects shows a higher photocatalytic activity for decomposition of a methylene blue solution compared with that of the perfect TiO2 sample.The photocatalytic mechanism is discussed based on the density functional theory calculations and photoluminescence spectroscopy measurements.

Photocatalytic H2 generation via CoP quantum-dot-modified g-C3N4 synthesized by electroless plating

Photocatalytic water splitting is a promising method for hydrogen production.Numerous efficient photocatalysts have been synthesized and utilized.However,photocatalysts without a noble metal as the co-catalyst have been rarely reported.Herein,a CoP co-catalyst-modified graphitic-C3N4(g-C3N4/CoP)is investigated for photocatalytic water splitting to produce H2.The g-C3N4/CoP composite is synthesized in two steps.The first step is related to thermal decomposition,and the second step involves an electroless plating technique.The photocatalytic activity for hydrogen evolution reactions of g-C3N4 is distinctly increased by loading the appropriate amount of CoP quantum dots(QDs).Among the as-synthesized samples,the optimized one(g-C3N4/CoP-4%)shows exceptional photocatalytic activity as compared with pristine g-C3N4,generating H2 at a rate of 936μmol g^-1 h^-1,even higher than that of g-C3N4 with 4 wt%Pt(665μmol g^-1 h^-1).The UV-visible and optical absorption behavior confirms that g-C3N4 has an absorption edge at 451 nm,but after being composited with CoP,g-C3N4/CoP-4%has an absorption edge at 497 nm.Furthermore,photoluminescence and photocurrent measurements confirm that loading CoP QDs to pristine g-C3N4 not only enhances the charge separation,but also improves the transfer of photogenerated e--h+pairs,thus improving the photocatalytic performance of the catalyst to generate H2.This work demonstrates a feasible strategy for the synthesis of highly efficient metal phosphide-loaded g-C3N4 for hydrogen generation.

Expert consensus on the diagnosis and treatment of thrombocytopenia in adult critical care patients in China

Thrombocytopenia is a common complication of critical care patients.The rates of bleeding events and mortality are also significantly increased in critical care patients with thrombocytopenia.Therefore,the Critical Care Medicine Committee of Chinese People’s Liberation Army(PLA)worked with Chinese Society of Laboratory Medicine,Chinese Medical Association to develop this consensus to provide guidance for clinical practice.The consensus includes five sections and 27 items:the definition of thrombocytopenia,etiology and pathophysiology,diagnosis and differential diagnosis,treatment and prevention.

Interpretations and comments for expert consensus on the diagnosis and treatment of heat stroke in China

Heat stroke is the most severe type of heat illness,it is often accompanied by severe multiorgan damage and has a high fatality rate.In January 2020,based on new research evidence and the experiences of Chinese experts in heat stroke,the Expert Group of Heat Stroke Prevention and Treatment of the Chinese People’s Liberation Army(PLA)and the Professional Committee of Critical Care Medicine of the Chinese PLA jointly issued a new Expert Consensus on the Diagnosis and Treatment of Heat Stroke in China.This article aims to interpret and supplement the major updates to the new consensus.

CAG-repeat variant in the polymerase γ gene and male infertility in the Chinese population： a meta-analysis

Several studies have reported a relationship between the length of the CAG-repeat in the polymerase y （POLG） gene and male infertility. However, other studies have not reproduced this result. In our study, the POLG-CAG-repeat length was analyzed in 535 healthy individuals from six Chinese Han populations living in different provinces. The frequencies of IO-CAG alleles and genotypes were high （97.38 and 94.13%, respectively）, with no significant difference among the six Chinese Han populations. Furthermore, we determined the distribution of the POLG-CAG-repeat in 150 infertile men and 126 fertile men. Our study suggested that the distributions of POLG-CAG-repeat alleles and genotypes were not significantly different between infertile （95.67 and 92.67%, respectively） and fertile men （97.22 and 94.44%, respectively）. In a subsequent meta-analysis, combining our data with data from previous studies, a comparison of the CAG-repeat alleles in fertile versus infertile men showed no obvious risk for male infertility associated with any particular allele （pooled odds ratio （0R）=0.94; 95% confidence interval （CI）： 0.60-1.48）. The significance level was not attained with any of the following genetic models： homozygote comparison （not lO/not 10 versus 10110： OR= 1.34; 95% Ch 0.66-2.72）, heterozygote comparison （lO/not 10 versus 10/10： OR= 1.04; 95% Ch 0.78-1.38）, dominant model comparison （not lO/not 10＋ 101 not 10 versus 10110. OR= 1.08; 95% Ch 0.79-1.47） and recessive genetic comparison （not lO/not 10 versus lO/not 10＋ 10/10- OR= 1.31; 95% Ch 0.68-2.55）. In conclusion, there is no significant difference of the frequencies of POLG-CAG-repeat variants among six Chinese Han populations, and this polymorphism may not be associated with Chinese male infertility. On the basis of a meta-analysis, there is no obvious association between CAG-repeat variants of the POLG gene and male infertility.

CuInS_(2)quantum-dot-modified g-C_(3)N_(4)S-scheme heterojunction photocatalyst for hydrogen production and tetracycline degradation

CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption activity.The photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light respectively.The optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN itself.The enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional interface.This work is an effort to adjust CN-based polysulfide QD for speedy photocatalysis.The enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.

One-step pore diffusion mechanism of Li^(+) in solid electrolyte interphase for fast-charging lithium-ion battery

Li^(+) transport in solid electrolyte interphase is recognized as important factor,which has become a research hotspot.Recently,an one-step pore diffusion mechanism for Li^(+) transport through solid electrolyte interphase was proposed,which was different from previous two-step mechanism.Such one-step pore diffusion process could effectively eliminate the dynamic limitations of Li^(+) transport in solid electrolyte interphase (SEI) for rapid charging process.The work will contribute to the development of rapid charging lithium-ion batteries.

Selective dissolution for stabilizing solid electrolyte interphase

With pursuing high energy density batteries,traditional graphite anode could be unable to meet current needs[1-4].The high-capacity anodes have attracted increasing attention,such as lithium anodes and alloy-type anodes[5-8].Silicon anode,as a high-capacity alloy-type anode(3579 mAh/g),has attracted great attention[9].However,due to its unique electrochemical mechanism,significant changes in volume and morphology during charge/discharge process could lead to the decrease in cycling stability[9,10].Therefore,it is still challenging for silicon anode in tackling volume expansion and unstable interfaces.

Strong association of SLCIA1 and DPF3 gene variants with idiopathic male infertility in Han Chinese

Male infertility is a multifactorial syndrome encompassing a wide variety of disorders. In recent years, several genome-wide single-nucleotide polymorphism （SNP） association studies （GWAS） have been performed on azoospermia and/or oligozoospermia in different populations including two GWAS on nonobstructive azoospermia in China; however, the association of SNPs with idiopathic male infertility, especially asthenozoospermia and oligozoospermia, and their correlation with semen parameters are still not clear. To investigate genetic variants associated with idiopathic male infertility （asthenozoospermia, oligozoospermia, and oligoasthenozoospermia） in Chinese Han people, 20 candidate SNPs were selected from GWAS results and genotyped using the Sequenom MassARRAY assay. A total of 136 subfertile men and 456 healthy fertile men were recruited, rs6476866 in SLCIA1 （P = 1.919E-4, OR = 0.5905, 95% Ch 0.447-0.78） and rs10129954 in DPF3 （P = 0.0023, OR = 2.199, 95% Ch 1.311-3.689） were strongly associated with idiopathic male infertility. In addition, positive associations were observed between asthenozoospermia and rs215702 in LSM5 （P= 0.0016, OR = 1.479, 95% CI： 1.075-2.033） and between oligoasthenozoospermia and rs2477686 in PEXIO （P= 0.0011, OR = 2.935, 95% Ch 1.492-5.775）. In addition, six SNPs （rs215702 in LSMS, rs6476866 in SLCIA1, rs10129954 in DPF3, rs1801133 in MTHFR, rs2477686 in PEXIO, and rs10841496 in PED3A） were significantly correlated with semen quality alterations. Our results suggest that idiopathic male infertility in different ethnic groups may share the same mechanism or pathway. Cohort expansion and further mechanistic studies on the role of genetic factors that influence spermatogenesis and sperm progressive motility are suggested.

Impact of DNA mismatch repair system alterations on human fertility and related treatments

DNA mismatch repair （MMR） is one of the biological pathways, which plays a critical role in DNA home- ostasis, primarily by repairing base-pair mismatches and insertion/deletion loops that occur during DNA replication. MMR also takes part in other metabolic pathways and regulates cell cycle arrest. Defects in MMR are associated with genomic instability, predisposition to certain types of cancers and resistance to certain therapeutic drugs. Moreover, genetic and epigenetic alterations in the MMR system demonstrate a significant relationship with human fertility and related treatments, which helps us to understand the etiology and susceptibility of human infertility. Alterations in the MMR system may also influence the health of offspring conceived by assisted reproductive technology in humans. However, further studies are needed to explore the specific mechanisms by which the MMR system may affect human infertility. This review addresses the physiological mechanisms of the MMR system and associations between altera- tions of the MMR system and human fertility and related treatments, and potential effects on the next generation.