[Neurobehavioral effects of explosion exposure on acute and chronic traumatic brain injury in rats]

Objective: To explore the effect of nerve injury in rats by neurobehavioral experiments, in order to provide a model and idea for further clarification of the traumatic brain injury mechanism under explosion exposure. Methods: From May 2021 to August 2022, 160 SPF male rats were randomly divided into four groups, including control group, 60 kPa group (low intensity group), 90 kPa group (medium intensity group) and 120 kPa group (high intensity group). The blast induced traumatic brain injury (bTBI) model of rats was established by using the shock tube platform to simulate the shock wave parameters of the explosion overpressure of 60 kPa, 90 kPa and 120 kPa. Acute observation was carried out after 24 h and 7 d of explosive exposure, and chronic recovery observation was carried out after 28 d and 90 d. The time effect of shock wave brain injury in different situations was discussed by open field, light dark test, active avoidance test. Finally, the results of brain injury in rats were detected by pathological tissue staining. Results: After 24 h explosion exposure, compared with the control group, the rest time of rats in low and high intensity groups increased, the total movement distance decreased, and the number of visits to the camera obscura decreased, with statistical significance (P<0.05). After 7 days of exposure, compared with the control group, the rest time of rats in high intensity group increased, and the number of visits to the obscura decreased, with statistical significance (P<0.05). After 28 and 90 days of exposure, compared with the control group, there were no significant differences in rest time, total exercise distance and times of visiting the camera obscura in all intensity groups (P>0.05). After 24 h of explosive exposure, compared with the control group, the cell morphology of rats in each intensity group was normal, and no inflammatory cell infiltration was observed. Conclusion: In the acute phase (24 h) of blast exposure, rats have no desire to explore the outside world, and shock wave exposure may damage the neurological function of rats.

Variation in microbiological heterogeneity in Chinese strong-flavor Baijiu fermentation for four representative varieties of sorghum

The quality and composition of strong-flavor Baijiu (SFB), a type of Chinese liquor, depends on the variety of sorghum used in fermentation. However, comprehensive in situ studies measuring the effects sorghum varieties on the fermentation are lacking and the underlying microbial mechanisms remains poorly understood. We studied the in situ fermentation of SFB by using metagenomic, metaproteomic, and metabolomic techniques across four sorghum varieties. Sensory characteristics were best for SFB made from glutinous variety Luzhouhong, followed by glutinous hybrid Jinnuoliang and Jinuoliang, and those made with non-glutinous Dongzajiao. In agreement with sensory evaluations, the volatile composition of SFB samples differed between sorghum varieties (P < 0.05). Fermentation of different sorghum varieties varied in microbial diversity, structure, volatile compounds, and physicochemical properties (pH, temperature, starch, reducing sugar, and moisture) (P < 0.05), with most changes occurring within the first 21 days. Additionally, the microbial interactions and their relationship with volatiles, as well as the physicochemical factors that govern microbial succession, differed between varieties of sorghum. The number of physicochemical factors affecting bacterial communities outweighed those affecting fungal communities, suggesting that bacteria were less resilient to the brewing conditions. This correlates with the finding that bacteria play a major role in the differences in microbial communities and metabolic functions during fermentation with the different varieties of sorghum. Metagenomic function analysis revealed differences in amino acid and carbohydrate metabolism between sorghum varieties throughout most of the brewing process. Metaproteomics further indicated most differential proteins were found in these two pathways, related to differences in volatiles between sorghum varieties of Baijiu and originating from Lactobacillus. These results provide insight into the microbial principles underlying Baijiu production and can be used to improve the quality of Baijiu by selecting the appropriate raw materials and optimizing fermentation parameters.

Brevinin-2PN, an antimicrobial peptide identified from dark-spotted frog (Pelophylax nigromaculatus), exhibits wound-healing activity

Brevinins exhibit a wide range of structural features and strong biological activities. Brevinin-2, derived from several amphibians, has shown antimicrobial activities. However, little is known about the wound-healing activity of brevinin-2. In this study, brevinin-2 cDNA was identified from the skin transcriptome of the dark-spotted frog (Pelophylax nigromaculatus) and it comprises a signal peptide, a propeptide, and a mature peptide. Sequence alignment with brevinin-2 derived from other amphibians showed variability of the mature peptide, and the presence of a C-terminal cyclic heptapeptide domain (Cys-Lys-Xaa4-Cys) in the mature peptide. Dark-spotted frog brevinin-2 belonged to the brevinin-2 cluster and was closely related to brevinin-2HB1 from Pelophylax hubeiensis. Synthetic dark-spotted frog brevinin-2 mature peptide (brevinin-2PN) exhibited antibacterial activity against several pathogens by destroying cell membrane integrity and hydrolysis of genomic DNA. Brevinin-2PN exhibited significant wound-healing activity by accelerating the healing of human skin fibroblast cell scratches, influencing cell migration, and stimulating gene expression of growth factors.

[Clinical validation of the 2020 diagnostic approach for pediatric autoimmune encephalitis in a single center]

Objective: To evaluate the value of the 2020 diagnostic criteria (Cellucci criteria) for pediatric autoimmune encephalitis (AE) in children with suspected AE in a single center. Methods: The clinical data of 121 children hospitalized at the First Affiliated Hospital of Zhengzhou University from October 2019 to October 2021, with a diagnosis of suspected AE, were retrospectively collected and analyzed. The children were divided into definite antibody-positive AE (dAPAE), probable antibody-negative AE (prANAE), possible AE (pAE) and non-AE groups according to the Chinese expert consensus and the Graus criteria. A new diagnosis was made according to the Cellucci criteria which was compared with the clinical diagnosis to evaluate the diagnostic value of the Cellucci criteria. The Mann-Whitney U test, Kruskal-Wallis test, and χ² test were used to compare the differences among groups. The sensitivity and specificity were used to evaluate efficacy of the Cellucci criteria. Results: Among the 121 children, 72 were males and 49 were females, with an age of 10.3 (6.5, 14.0) years at disease onset. There were 99 cases diagnosed as AE according the clinical diagnosis (58 males and 41 females), of which 43 cases were diagnosed as dAPAE, 14 cases as prANAE and 42 cases as pAE, and the other 22 cases were not AE (14 males and 8 females). The top 2 initial symptoms in the 99 children with AE were seizures (53 cases, 53.5%) and abnormal mental behaviors (35 cases, 35.4%). And the most common symptoms during the course of the disease were abnormal mental behaviors (77 cases, 77.8%) and seizures (64 cases, 64.6%). There were statistically differences in the incidence of consciousness disorders, autonomic dysfunctions during the course of the disease and the length of hospitalization among the 4 groups (χ²=21.63, 13.74, H=22.60, all P<0.05). Ninety-six of the 121 children were tested for AE-related antibodies, of which 45 cases (46.9%) were antibody-positive. According to the Cellucci criteria, 42 cases were diagnosed as dAPAE, 34 cases as prANAE and 14 cases as pAE. Compared with the clinical diagnosis, the sensitivity of the Cellucci criteria for the diagnosis of the 3 types of AE were 93.02%, 92.86% and 87.88%, and the specificity were 96.23%, 74.39% and 86.36%, respectively. Conclusions: The Cellucci criteria has a high sensitivity and specificity for the diagnosis of pAE and dAPAE in the clinical management of children with suspected AE, while a high sensitivity but low specificity for the diagnosis of prANAE. Therefore, it is recommended to apply the Cellucci criteria selectively in clinical practice according to the actual situation, especially in the diagnosis of prANAE.

Observation of Spin Splitting Torque in a Collinear Antiferromagnet RuO_{2}

Current-induced spin torques provide efficient data writing approaches for magnetic memories. Recently, the spin splitting torque (SST) was theoretically predicted, which combines advantages of conventional spin transfer torque (STT) and spin-orbit torque (SOT) as well as enables controllable spin polarization. Here we provide the experimental evidence of SST in collinear antiferromagnet RuO_{2} films. The spin current direction is found to be correlated to the crystal orientation of RuO_{2} and the spin polarization direction is dependent on (parallel to) the Néel vector. These features are quite characteristic for the predicted SST. Our finding not only presents a new member for the spin torques besides traditional STT and SOT, but also proposes a promising spin source RuO_{2} for spintronics.

Antimicrobial and immunomodulatory activity of beta-defensin from the Chinese spiny frog (Quasipaa spinosa)

The β-defensins are important components of the vertebrate innate immune system. While mammalian β-defensins have wide-ranging antibacterial and immunomodulatory activities, those of amphibians remain largely uncharacterised. In this study, β-defensin cDNA was identified from the skin transcriptome of the Chinese spiny frog Quasipaa spinosa. This β-defensin (QS-BD) consists of a signal and a mature peptide. Sequence alignments with other amphibian β-defensins showed conservation of the functional mature peptide and that its closest relative is β-defensin from Zhangixalus puerensis. Synthetic QS-BD showed antibacterial activity against Vibrio vulnificus, Vibrio harveyi, Streptococcus iniae, and Aeromonas hydrophila. QS-BD showed bactericidal activity by destroying the cell membrane integrity, but did not hydrolyse genomic DNA. QS-BD treatment promoted respiratory bursts and upregulated the expression of interleukin-1β and tumour necrosis factor-α in the murine leukemic monocyte/macrophage cell line RAW264.7. This is the first demonstration of immunomodulatory activity by an amphibian β-defensin.

[Evaluation of developmental toxicity of ammonium dinitramide by micromass culture and embryonic stem cells models]

Objective: To evaluated the potential developmental toxicity and teratogenicity of ammonium dinitroamide (ADN) by micromass test (MM Test) and embryonic stem cell test models. Methods: In September 2018, rat embryos were isolated and limb bud cells were collected. The limb bud cells were treated with different concentrations of ADN (0, 312.50, 625.00, 1250.00, 2500.00, 5000.00, 10000.00 μg/ml) . Half proliferation inhibitory concentration and half differentiation inhibitory concentration were calculated and the teratogenic effects were evaluated according to the criteria. For the embryonic stem cell test, the effects of different concentrations of ADN (0, 39.06, 78.13, 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml) on the differentiation of mouse embryonic stem cells (mESCs) into myocardial cells and the cytotoxicity of mESCs and 3T3 cells were detected. The embryonic toxicity was evaluated according to the criteria. In this study, both 5-fluorouracil (5-FU) , a known strong embryonic toxic drug, and penicillin-G (P-G) , a non-embryonic toxic drug, were used to verify the effectiveness of the model, and the validated test model was applied to evaluate the embryonic toxicity of ADN. Results: In the MM Test, the inhibition rates of proliferation and differentiation of limb bud cells in ADN groups were higher than that in control group (P<0.05) . And the half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on limb bud cells were 7480.32 and 4526.09 μg/ml, respectively. ADN was determined to be non-teratogenic by standard. In the embryonic stem cell test, the inhibition rates of mESCs proliferation in ADN groups were higher than that in control group, and the inhibition rates of 3T3 cells in 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml ADN groups were higher than that in control group (P<0.05) . The half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on mESCs were 1851.73 and 1796.39 μg/ml, respectively, and the half proliferation inhibitory concentration on 3T3 cells was 3334.35 μg/ml. ADN was determined to be non-embryotoxic by standard. Conclusion: After evaluation by MM Test and embryonic stem cell models, ADN has no embryo toxicity and is a non-teratogenic substance.

Influencing factors of resource utilisation in haemodialysis patients-Based on socioecological pyramid model

Aims and objectives

To describe the current situation and analyse influencing factors of resource utilisation in maintenance haemodialysis patients.

Background

The self‐management level of patients undergoing maintenance haemodialysis in China is low. The applicability of the Chronic Illness Resources Survey in Chinese maintenance haemodialysis patients has been validated, and this survey can be used to assess the utilisation of self‐management support resources among haemodialysis patients. Determining the influencing factors of resource utilisation can help improve the self‐management behaviour of haemodialysis patients and control the progression of the disease.

Design

A descriptive study design was chosen.

Methods

A convenience sample of 314 patients undergoing haemodialysis was recruited from dialysis centres in three hospitals in western Xinjiang from June 2018–April 2019. SPSS19.0 software was used to describe the current situation of resource utilisation. Moreover, t test, analysis of variance and multivariate linear regression were applied to explore the influencing factors of patients’ resource utilisation. Standards for observational studies STROBE Statement checklist‐v4 were chosen on reporting the study process.

Results

The average score of the total resource utilisation was 2.95 ± 0.51. The average item score of seven dimensions from high to low was 3.46 for medical staff, 3.32 for personal, 3.22 for family and friends, 3.16 for work‐related, 3.12 for media policy, 2.55 for neighbourhood/community and 2.23 for organisation. Multiple linear regression showed that there have six main factors, which explained 65.4% of the variance of haemodialysis patients’ resource utilisation.

Conclusions

The personal, family and friends, work and media and policy subscales were rated the highest, with support from neighbourhood/community and organisation rated the lowest. In general, participants perceived moderate levels of support. Government and healthcare team should pay more attention on haemodialysis patients who had low level of education, poor economic conditions and poor mental condition.

Relevance to clinical practice

ESRD has caused a burden on healthcare expenditure and has become a critical public health problem worldwide. Self‐management is particularly important for dialysis patients which have attracted extensive interest. In the future research, we can use this questionnaire to evaluate the related resources of disease management of dialysis patients, encourage patients to make full use of the resources around them and focus on those patients with low education and monthly income level and bad mental state.

Interferometric control of magnon-induced nearly perfect absorption in cavity magnonics

The perfect absorption of electromagnetic waves has promoted many applications, including photovoltaics, radar cloaking, and molecular detection. Unlike conventional methods of critical coupling that require asymmetric boundaries or coherent perfect absorption that require multiple coherent incident beams, here we demonstrate single-beam perfect absorption in an on-chip cavity magnonic device without breaking its boundary symmetry. By exploiting magnon-mediated interference between two internal channels, both reflection and transmission of our device can be suppressed to zero, resulting in magnon-induced nearly perfect absorption (MIPA). Such interference can be tuned by the strength and direction of an external magnetic field, thus showing versatile controllability. Furthermore, the same multi-channel interference responsible for MIPA also produces level attraction (LA)-like hybridization between a cavity magnon polariton mode and a cavity photon mode, demonstrating that LA-like hybridization can be surprisingly realized in a coherently coupled system.

High Curie temperature and carrier mobility of novel Fe, Co and Ni carbide MXenes

Two-dimensional (2D) magnets with room temperature ferromagnetism and semiconductors with moderate band gap and high carrier mobility are highly desired for applications in nanoscale electronics and spintronics. By performing the first-principles calculations, we investigate novel Fe, Co, Ni carbide based pristine (M₂C) and functionalized (M₂CT₂, T: F, O, OH) MXenes. Our calculations show that Fe₂C, Co₂C, Ni₂C, Fe₂CF₂, Fe₂CO₂, Fe₂C(OH)₂, Co₂CF₂, Co₂C(OH)₂ and Ni₂CF₂ are dynamically and mechanically stable. More importantly, Fe₂C, Co₂C, Fe₂CF₂ and Fe₂C(OH)₂ exhibit intrinsic ferromagnetism (magnetic moments 2-5μ_B per unit cell). Monte Carlo simulations suggest high Curie temperatures of 590 and 920 K for Fe₂C and Fe₂CF₂, respectively, at the HSE06 level owing to the large spin magnetic moments and strong ferromagnetic coupling. Based on the deformation potential theory, we predict high and anisotropic hole mobility (0.2-1.4 × 10⁴ cm² V^-1 s^-1) for semiconducting Fe₂CO₂ and Co₂C(OH)₂. Additionally, Ni₂CF₂ demonstrates highly anisotropic electron mobility together with a direct band gap. Our results further show the effectiveness of surface functionalization in modulating the electronic and magnetic properties and broadening the properties of MXenes to achieve long-range intrinsic ferromagnetism well above room temperature and high carrier mobility.

In vitro degradation and cytocompatibility of a low temperature in-situ grown self-healing Mg-Al LDH coating on MAO-coated magnesium alloy AZ31

Basically, Mg-Al layered double hydroxide (LDH) coatings are prepared on the surface of micro-arc oxidation (MAO) coated magnesium (Mg) alloys at a high temperature or a low pH value. This scenario leads to the growth rate of LDH coating inferior to the dissolution rate of the MAO coating. This in turn results in limited corrosion resistance of the composite coating. In this study, a Mg-Al LDH coating on MAO-coated Mg alloy AZ31 is prepared through a water bath with a higher pH (13.76) at a lower temperature (60 °C). FE-SEM, EDS, XRD, XPS, and FT-IR are applied to analyze the surface morphology, chemical compositions, and growth process. Electrochemical polarization, electrochemical impedance spectroscopy (EIS) and hydrogen evolution tests are employed to evaluate the corrosion resistance of the samples. The results disclose that the MAO coating is completely covered by the nanosheet-structured LDH coating with a thickness of approximately 3.8 μm. The corrosion current density of the MAO-LDH composite coating is decreased four orders of magnitude in comparison to its substrate; the presence of a wide passivation region in anodic polarization branch demonstrates its strong self-healing ability, indicating the hybrid coating possesses excellent corrosion resistance. The formation mechanism of the LDH coating on the MAO-coated Mg alloy is proposed. Furthermore, the cytocompatibility is assessed via an indirect extraction test for MC3T3-E1 pre-osteoblasts, which indicates an acceptable cytocompatibility of osteoblasts for the composite coating.

Wnt2 overexpression protects against PINK1 mutant‑induced mitochondrial dysfunction and oxidative stress

The PTEN induced putative kinase 1 (PINK1) mutation is the second most common cause of autosomal recessive adolescent Parkinson's disease (PD). Furthermore, mitochondrial disorders and oxidative stress are important mechanisms in the pathogenesis of PD. Numerous members of the Wnt family have been found to be associated with neurodegenerative diseases. Therefore, the present study investigated the role of the Wnt2 gene in PINK1B9 transgenic flies, which is a PD model, and its underlying mechanism. It was identified that overexpression of Wnt2 reduced the abnormality rate of PD transgenic Drosophila and improved their flight ability, while other intervention groups had no significant effect. Furthermore, an increase in ATP concentration normalized mitochondrial morphology, and increased the mRNA expression levels of NADH‑ubiquinone oxidoreductase chain 1 (ND1), ND42, ND75, succinate dehydrogenase complex subunits B, Cytochrome b and Cyclooxygenase 1, which are associated with Wnt2 overexpression. Moreover, overexpression of Wnt2 in PD transgenic Drosophila resulted in the downregulation of reactive oxygen species and malondialdehyde production, and increased manganese superoxide dismutase (MnSOD), while glutathione was not significantly affected. It was found that overexpression of Wnt2 did not alter the protein expression of β‑catenin in PINK1B9 transgenic Drosophila, but did increase the expression levels of PPARG coactivator 1α (PGC‑1α) and forkhead box sub‑group O (FOXO). Collectively, the present results indicated that the Wnt2 gene may have a protective effect on PD PINK1B9 transgenic Drosophila. Thus, it was speculated that the reduction of oxidative stress and the restoration of mitochondrial function via Wnt2 overexpression may be related to the PGC‑1α/FOXO/MnSOD signaling pathway in PINK1 mutant transgenic Drosophila.

[Surgical treatment strategy for endograft infection after thoracic endovascular aortic repair]

Objective: To examine the results of surgical treatment for endograft infection after thoracic endovascular aortic repair (TEAVR). Methods: Clinical data of 7 patients underwent surgical treatment for endograft infection after TEAVR at Department of Cardiothoracic Surgery, Changhai Hospital, the Navy Medical University between January 2016 and December 2018 were analyzed retrospectively. There were 6 males and 1 female, aging (51.5±16.7) years (range: 25 to 68 years). The origin of the aortic disease was descending aortic aneurysm in 5 cases, and Stanford B aortic dissection in 2 cases. Abdominal aorta below the level of the diaphragm was not involved in all patients. Two patients received "chimney technology" for left subclavian artery procedures. Time to infection was 5(3) months (M(Q(R))) (range: 1 to 24 months). Aortic endograft infection was diagnosed with a combination of microbiology (positive blood cultures, except one with mycotic), radiological evidence and clinical evidence of sepsis. Two patients suffered from aorto-esophageal fistula received emergency surgery, others were treated with elective surgery. Extra-anatomic prosthetic graft bypass was used for reconstruction of aorta, infected endogarft and aorta was removed, sac drainage was performed. Aorto-esophageal fistula was procedured according to the degree of lesions. All patients received antibiotics with specialist advice for 6 to 8 weeks. Results: One patient died due to septic shock. In the follow-time (range: 6 to 24 months), 1 patient suffered from thoracic infection in 3 months after surgery, an other patient got iliac abscess after a month. Conclusions: Endograft infection after TEAVR is high risk but may be curative. Appropriate selection of patients for infected endograft explantation could get a satisfied results.

[Medical staff's exposure to solid particles and health impact survey]

Objective: To investigate the current situation of exposure of solid particles in medical staff and the occurrence of related diseases, and to understand the distribution characteristics of occupational exposure and the influencing factors. Methods: In August 2016, the stratified cluster sampling method was adopted to select three tertiary general hospitals with different regions, different administrative levels and departments in Shandong Province. A face-to-face questionnaire survey was conducted on the basic situation of the staff of the hospital, the status of exposure to occupational hazards and the health effects. Two-class logistic regression analysis was used to analyze the relationship between medical staff's solid particle contact and occupational health effects. In August 2016, the stratified cluster sampling method was adopted to select three tertiary general hospitals with different regions, different administrative levels and departments in Shandong Province, which were in contact with the basic conditions and occupational hazards of the staff of the hospital. Current situation and health impacts were conducted face-to-face questionnaires. Two-class logistic regression analysis was used to analyze the relationship between medical staff's solid particle contact and occupational health effects. Results: The overall contact rate of solid particles of medical staff was 41.5% (1843/4 446) , and the solid particles with the highest contact rate were 28.2% (1254/4 446) of talc dust. There was a statistically significant difference in the contact rate of solid particles between medical staff of different occupations, current working age, education and hospital type (χ(2)=76.30, 41.26, 26.16, 188.97, P<0.05) . There were significant differences in the conditions and types of solid particles in different departments (χ(2)=740.23, P<0.05) . Compared with the control group, the incidence of allergic asthma, chronic tracheobronchitis and dermatitis was higher in the contact group medical staff (P<0.05) . Contact with zirconia dust, talc dust, cotton dust is a risk factor for dermatitis in medical staff (OR=2.09, 1.45, 1.34) ; exposure to zirconia dust and cotton dust is a risk factor for chronic tracheobronchitis in medical staff (OR=2.38, 1.66) ; exposure to zirconia dust, gypsum dust is a risk factor for allergic asthma in medical staff (OR=3.90, 1.52) . Conclusion: The contact rate of solid particles in medical staff is high, and there are many types of contact. Frequent contacted with solid particles is a dangerous cause of related diseases. The working environment of medical staff should be further monitored and be strengthen the targeted protective measures and regulatory systems for the exposure of medical personnel to solid particles.

Magainin-modified polydopamine nanoparticles for photothermal killing of bacteria at low temperature

Photothermal therapy (PTT) is a promising method to kill bacteria because of the broad-spectrum of antibacterial activity and the ability of spatiotemporal regulation. In the previously reported systems, light induced high temperature (˜70 °C) was essential for effectively killing of bacteria, which, however, would also damage nearby nontarget cells or tissues. Here we report photothermal nanoparticles (NPs) for more targeting and killing bacteria at a relative low temperature. Polydopamine (PDA) was chosen to prepare NPs because of its excellent capability of photothermal conversion. Magainin I (MagI) which is an antimicrobial peptide was used to modify NPs' surface because it can specifically interact with bacteria. We demonstrate that MagI-PEG@PDA NPs effectively killed E. coli at a low temperature of ˜45 °C upon near-infrared (NIR) light irradiation. In contrast, the native PDA NPs under light irradiation or the MagI-PEG@PDA NPs themselves showed no bacteria killing ability. This work highlights the importance of close interaction between the target bacteria and the photothermal materials and may promote the practical clinical applications of the PTT.

Pmma-XO (X = C, Si, Ge) monolayer as promising anchoring materials for lithium-sulfur battery: a first-principles study

Lithium-sulfur (Li-S) batteries hold great promise for the next-generation lithium-ion energy storage devices. A key issue in the Li-S batteries is, however, the dissolving and migrating of the soluble polysulfides during the charge and discharge processes and introducing anchoring materials (AM) in the batteries effectively prevent the problem and improve the cycling stability of the Li-S batteries. Herein, Pmma-XO (X = C, Si, Ge, Sn) monolayers are introduced as AM to confine the lithium polysulfides and their anchoring properties are studied with the density functional theory methods. Particularly, Pmma-SiO and GeO monolayers are studied for the first time, and our calculations show that these two materials are stable semiconductive monolayers with direct-band-gaps and moderate binding with lithium polysulfides Li₂S _n (n = 8, 6, 4, 2 and 1). The Pmma-SiO and GeO trap Li₂S _n species on their surfaces and keep them intact during the charge and discharge, and the adsorption of Li₂S _n species leads to the enhanced conductivity of Pmma-SiO and GeO monolayers. Our study suggests that the Pmma-SiO and GeO monolayers are the promising AM for highly efficient Li-S batteries.

Mating pattern, female reproduction and sexual size dimorphism in a narrow-mouthed frog (Microhyla fissipes)

The difference in body size and/or shape between males and females, called sexual size dimorphism, is widely accepted as the evolutionary consequence of the difference between reproductive roles. To study the mating pattern, female reproduction and sexual size dimorphism in a population of Microhyla fissipes, amplexus pairs were collected, and the snout-vent length of males and females, female reproductive traits and fertilization rate were measured. If the body size of amplexed females is larger than that of amplectant males, this is referred to as a female-larger pair, a phenomenon that was often observed for M. fissipes in this study. Interestingly, snout-vent length of males in male-larger pairs was greater than that in female-larger pairs, however the post-spawning body mass, clutch size, egg dry mass and clutch dry mass did not differ between both types of pairs. Snout-vent length of males was positively related to that of females in each amplexus pair. After accounting for the snout-vent lengths of females, we showed that snout-vent lengths of males in male-larger pairs were greater than those of females in female-larger pairs. The snout-vent length ratio of males and females was not related to fertilization rate in each amplexus pair. The mean fertilization rate was not different between both amplexus pairs. These results suggest that (1) M. fissipes displays female-biased sexual size dimorphism and has two amplexus types with size-assortative mating; (2) the snout-vent length ratio of males and females in each amplexus type was consistent with the inverse of Rensch’s rule, and was driven by the combined effect of sexual selection and fecundity selection; (3) females with a larger body size were preferred by males due to their higher fecundity, while the body size of males was not important for fertilization success.

Molecular characterization of a hepcidin homologue in starry flounder (Platichthys stellatus) and its synergistic interaction with antibiotics

Hepcidins are small cysteine-rich antimicrobial peptides that play an important role in host immunity against pathogenic organisms. Most fish hepcidins exert bactericidal activities against a wide range of pathogens. In this study, we identified a cDNA sequence encoding a hepcidin homologue (PsHepcidin) in the starry flounder Platichthys stellatus. The predicted amino acid sequence of PsHepcidin comprises a signal peptide and a prodomain, which are followed by the mature peptide. Sequence analysis revealed that PsHepcidin belongs to the fish HAMP2 cluster and that it is closely related to mudskipper hepcidin-2. Expression of PsHepcidin mRNA was detected in all examined immune-related tissues, with the highest transcript levels being found in the liver. In response to lipopolysaccharide treatment, PsHepcidin was significantly up-regulated in the liver, kidney, and spleen in a time-dependent manner. Chemically synthesized mature peptides of PsHepcidin were found to exhibit broad antimicrobial activity in vitro. We also investigated the combined effect of PsHepcidin and conventional antibiotics and found that these combinations showed synergistic effects against most of the examined bacterial strains. Collectively, the results of this study indicate that PsHepcidin exhibits potent antibacterial activity both independently and when used in combination with conventional antibiotics.

Pedobacter chitinilyticus sp. nov., a chitin-degrading bacterium isolated from wheat leaf tissue

A bacterium, designated strain CM134L-2^T, was isolated from a chitin-enriched wheat leaf microbiome in Chengdu, Sichuan province, China. It was Gram-stain-negative, strictly aerobic, non-spore-forming, motile, rod-shaped, and bright yellow in colour. Strain CM134L-2^T grew at 4-35 °C, at pH 6.0-9.0 and could use chitin as the only carbon resource. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CM134L-2^T was most closely related to Pedobacter nanyangensis Q-4^T (97.7 %) and Pedobacter zeaxanthinifaciens TDMA-5^T (97.4 %). Digital DNA-DNA hybridization (dDDH) values between strain CM134L-2^T with these two type strains were 26.8  and 20.8 %, respectively, and average nucleotide identity (ANI) values were 83.2 and 76.2 %; these values are lower than the proposed and generally accepted species boundaries of 70 % for dDDH and 95-96 % for ANI, which suggests strain CM134L-2^T represents a novel species. The genomic DNA G+C content of strain CM134L-2^T was 39.3 mol%, menaquinone-7 was the major respiratory quinone, phosphatidylethanolamine was the major polar lipid and the major components of the cellular fatty acids were iso-C15 : 0, and C16 : 1ω7c/C16 : 1ω6c (summed feature 3); these features supported the affiliation of strain CM134L-2^T to the genus Pedobacter. Overall, strain CM134L-2^T belongs to the genus Pedobacter, but can be classified as a novel species, for which the name Pedobacter chitinilyticus sp. nov. is proposed. The type strain is CM134L-2^T (=CGMCC 1.16520^T=KCTC 62643^T).

Bactericidal and Hemocompatible Coating via the Mixed-Charged Copolymer

Cationic antibacterial coating based on quaternary ammonium compounds, with an efficient and broad spectrum bactericidal property, has been widely used in various fields. However, the high density of positive charges tends to induce weak hemocompatibility, which hinders the application of the cationic antibacterial coating in blood-contacting devices and implants. It has been reported that a negatively charged surface can reduce blood coagulation, showing improved hemocompatibility. Here, we describe a strategy to combine the cationic and anionic groups by using mixed-charged copolymers. The copolymers of poly (quaternized vinyl pyridine- co- n-butyl methacrylate- co-methacrylate acid) [P(QVP- co- nBMA- co-MAA)] were synthesized through free radical copolymerization. The cationic group of QVP, the anionic group of MAA, and the hydrophobic group of nBMA were designed to provide bactericidal capability, hemocompatibility, and coating stability, respectively. Our findings show that the hydrophilicity of the copolymer coating increased, and its zeta potential decreased from positive charge to negative charge with the increase of the anionic/cationic ratio. Meanwhile, the bactericidal property of the copolymer coating was kept around a similar level compared with the pure quaternary ammonium copolymer coating. Furthermore, the coagulation time, platelet adhesion, and hemolysis tests revealed that the hemocompatibility of the copolymer coating improved with the addition of the anionic group. The mixed-charged copolymer combined both bactericidal property and hemocompatibility and has a promising potential in blood-contacting antibacterial devices and implants.

3-Fold-Periodic Size-Dependence in Electronic Properties of Monolayer-TMDC Nanotriangles

Stable nanotriangles of monolayer transitional metal dichalcogenides (referred herein as MS₂ mNTs) grown via ordinary deposition conditions, where M = Mo or W, exhibit a peculiar 3-fold periodic size-dependence in electronic and chemical properties. For " k" being the number of M atoms per edge, mNTs are (a) intrinsic-semiconducting when k = 3 i + 1, such as k = 7, 10, 13, 16; (b) metallic-like with no bandgap when k = 3 i; (c) n⁺ semiconducting when k = 3 i - 1. Besides changes in electronic properties, the catalytic properties for hydrogen evolution reaction also switch from active for k = 3 i and 3 i - 1 to inactive for k = 3 i + 1. The peculiar periodic size-dependence roots from the chemistry of edge-reconstruction and the consequential evolution of band structure. Further, such chemistry and thereby the size-dependence can be manipulated by adding or depleting the atomic concentration of sulfur atoms along the mNT edges.

[Cross-sectional survey of autism spectrum disorders in children aged 0-6 years in Hainan province]

Objective: To understand the prevalence of autism spectrum disorders (ASD) in children aged 0-6 years old and influencing factors in Hainan province. Methods: A total of 37 862 children aged 0-6 years were selected from 18 counties in Hainan province for a screening by using questionnaire of"warning signs in child development", then field diagnosis was made, and general descriptive statistic analysis was conducted. The prevalence of ASD and related factors were analyzed with χ(2) test and unconditional logistic regression model. Results: Among 37 862 children aged 0-6 years, 235 were diagnosed with ASD, the prevalence of ASD was 0.62% (0.99% in boys, 0.17% in girls), the differences was significant (χ(2)=101.91, P=0.000). The prevalence of ASD increased with age (χ(2)=288.62, P=0.000). The prevalence of ASD was significantly higher in urban area than in other areas (χ(2)=114.77, P=0.000). Factors such as full term pregnancy or not, neonatal asphyxia, father's characteristics, father's habit of chewing areca or smoking, mother's general mood, and mother's induced abortion history were the influencing factors for ASD. Conclusion: The prevalence of ASD in children aged 0-6 years was high in Hainan and was influenced by genetic factors, pregnancy and delivery process, parents unhealthy habit before and during pregnancy and other factors.

Utilization of a Wheat660K SNP array-derived high-density genetic map for high-resolution mapping of a major QTL for kernel number

In crop plants, a high-density genetic linkage map is essential for both genetic and genomic researches. The complexity and the large size of wheat genome have hampered the acquisition of a high-resolution genetic map. In this study, we report a high-density genetic map based on an individual mapping population using the Affymetrix Wheat660K single-nucleotide polymorphism (SNP) array as a probe in hexaploid wheat. The resultant genetic map consisted of 119 566 loci spanning 4424.4 cM, and 119 001 of those loci were SNP markers. This genetic map showed good collinearity with the 90 K and 820 K consensus genetic maps and was also in accordance with the recently released wheat whole genome assembly. The high-density wheat genetic map will provide a major resource for future genetic and genomic research in wheat. Moreover, a comparative genomics analysis among gramineous plant genomes was conducted based on the high-density wheat genetic map, providing an overview of the structural relationships among theses gramineous plant genomes. A major stable quantitative trait locus (QTL) for kernel number per spike was characterized, providing a solid foundation for the future high-resolution mapping and map-based cloning of the targeted QTL.

Clinical effects of comfort nursing in perianal abscess patients with postoperative pain

AIM

To evaluate the clinical effects of comfort nursing in patients with perianal abscess.

METHODS

Ninety perianal abscess patients with postoperative pain treated at our hospital were selected and divided into either a control group to receive routine nursing care alone or a study group to receive routine nursing care plus comfort nursing, with 45 cases in each group. Pain, anxiety and sleep quality of the two groups were compared between the two groups.

RESULTS

The numeric pain rating scale scores at different time points in the study group were significantly lower than those in the control group (t = 9.67, 13.53, 15.83, and 10.46, P < 0.05). The self-rating anxiety scale score were significantly lower in the study group than in the control group (t = 2.31, -18.04, P < 0.05); and the Pittsburgh sleep quality index were also significantly lower in the study group than in the control group (t = 9.47, P < 0.05).

CONCLUSION

The application of comfort nursing is helpful to reduce postoperative pain, relieve anxiety, and improve sleep quality in patients with perianal abscess.

Nanopolygons of Monolayer MS2: Best Morphology and Size for HER Catalysis

With first-principles calculations, we find a new strategy for developing high-performance catalysts for hydrogen evolution reaction (HER) via controlling the morphology and size of nanopolygons of monolayer transition-metal dichalcogenides (npm-MS₂, with M = Mo, W, or V). Particularly, through devising a quantitative method to measure HER-active sites per unit mass and using such HER site density to comparatively gauge npm-MS₂ performance, we identify three keys in making npm-MS₂ with optimal HER performance: (a) npm-MS₂ should be triangular with each edge being M-terminated and each edge-M atom passivated by one S atom; (b) each edge of npm-MoS₂ and WS₂ should have 5-6 metal atoms as HER site density drops below/above these sizes optimal both for HER and practical npm growth; and (c) npm-VS₂ is immune to this overly fastidious size dependence. Known experimental data on npm-MoS₂ indeed support the plausibility of practicing these design rules. We expect that raising the nucleation density and controlling the growth time to favor the production of our proposed ultrasmall npm-MS₂ are critical but practical. Research on npm-VS₂ would bear the highest impact because of its size-forgiving HER performance and relatively high abundance and low cost.

Ferromagnetism in Transitional Metal-Doped MoS2 Monolayer

Manipulating electronic and magnetic properties of two-dimensional (2D) transitional-metal dichalcogenides (TMDs) MX2 by doping has raised a lot of attention recently. By performing the first-principles calculations, we have investigated the structural, electronic, and magnetic properties of transitional metal (TM)-doped MoS2 at low and high impurity concentrations. Our calculation result indicates that the five elements of V-, Mn-, Fe-, Co-, and Cu-doped monolayer MoS2 at low impurity concentration all give rise to the good diluted magnetic semiconductors. By studying various configurations with different TM-TM separations, we found that the impurity atoms prefer to stay together in the nearest neighboring (NN) configuration, in which the doped TM atoms are FM coupling except for Fe doping at 12 % concentration. For V, Mn, and Fe doping, the total magnetic moment is smaller than the local magnetic moment of the dopants because the induced spins on the nearby host atoms are antiparallel to that of the doped atoms. In contrast, Co and Cu doping both give the higher total magnetic moment. Especially, Cu doping induces strong ferromagnetism relative to the local spins. However, the atomic structures of Co- and Cu-doped MoS2 deviate from the original prismatic configuration, and the magnetic moments of the doped systems decrease at 12 % impurity concentration although both elements give higher magnetic moments at 8 % impurity concentration. Our calculations indicate that V and Mn are promising candidates for engineering and manipulating the magnetism of the 2D TMDs.

Effects of TMEM9 gene on cell progression in hepatocellular carcinoma by RNA interference

Hepatocellular carcinoma (HCC) is a malignant tumor that has become a global health issue. The aim of the present study was to examine the role of transmembrane protein 9 (TMEM9) in cell progression, such as cell growth, cell cycle, cell metastasis of hepatoma cells, and to discuss the TMEM9 gene‑encoding protein as a potential therapy target of hepatoma. RT-qPCR was performed to examine TMEM9 expression in tumor tissues and adjacent tissues of patients with liver cancer. siRNAs were used to interfere TMEM9 in HepG2 and 7721 cells. A CCK-8 assay was performed to evaluate cell growth at 24, 48 and 72 h. Cell cycle and apoptosis were analyzed using flow cytometry. Transwell assays were used to determine cell invasion, migration and adhesion. The results showed that TMEM9 was expressed abnormally in liver cancers. TMEM9 expression increased significantly in the 34 examined patients. TMEM9 knockdown inhibited proliferation in the HepG2 and 7721 cells. The flow cytometric analysis revealed that TMEM9 knockdown by RNA interference resulted in G1 arrest and induced apoptosis. Cell invasion, migration and adhesion ability were also decreased. Western blotting indicated that expression of the cell cycle‑related proteins CDK1, EIF3H, RPL10L, S100A10, CCNB1 and CCNB2 was significantly decreased. In conclusion, TMEM9 plays an important role in the cell growth of hepatoma cells.

First-principles investigations of transition-metal doped bilayer WS2

The structural, electronic and magnetic properties of the AA and AB configurations of bilayer WS₂ with a TM (Mn, Fe, Co, Ni) doped in the interlayer position were studied by performing first-principles calculations.

Influence of intramuscular heat stimulation on modulation of nociception: complex role of central opioid receptors in descending facilitation and inhibition

It has been reported that the threshold to activate 'silent' or inactive descending facilitation of nociception is lower than that of descending inhibition. Thus, the development of pain therapy to effectively drive descending inhibition alone, without the confounding influences of facilitation is a challenge. To address this issue we investigated the effects of intramuscular stimulation with a heating-needle on spinal nociception, assessed by measuring nociceptive paw withdrawal reflex in rats. Additionally, involvement of the thalamic 'nociceptive discriminators' (thalamic mediodorsal (MD) and ventromedial (VM) nuclei), and opioid-mediated mechanisms were further explored. Descending facilitation and inhibition were elicited by 46°C noxious heating-needle stimulation, and were regulated by thalamic MD and VM nuclei, respectively. In contrast, innocuous heating-needle stimulation at a temperature of 43°C elicited descending inhibition modulated by the thalamic VM nucleus alone. Microinjection of μ/δ/κ-opioid receptor antagonists β-funaltrexamine hydrochloride/naltrindole/nor-binaltorphimine, into the VM nucleus attenuated the 46°C intramuscular heating-needle stimulation-evoked descending inhibition, whereas treatment of the MD nucleus with β-funaltrexamine hydrochloride significantly decreased the descending facilitation. By contrast, descending inhibition evoked by 43°C heating-needle stimulation was only depressed by naltrindole, as opposed to μ- and κ-opioid receptor antagonists, which failed to influence descending inhibition. The present study reveals distinct roles of μ-opioid receptors in the function of thalamic MD and VM nuclei,which exert facilitatory and inhibitory actions on nociception. Furthermore, innocuous, but not noxious, intramuscular heating-needle stimulation targeting δ-opioid receptors is suggested to be a promising avenue for the effective inhibition of pain.

Acute and joint toxicity of three agrochemicals to Chinese tiger frog (Hoplobatrachus chinensis) tadpoles

We studied acute and joint toxicity of three different agrochemicals (chlorantraniliprole, flubendiamide-abamectin and penoxsulam) to Chinese tiger frog (Hoplobatrachus chinensis) tadpoles with the method of stability water tests. Results showed that the three agrochemicals increased tadpole mortality. For acute toxicity, the LC50 values after 24, 48 and 72 h of chlorantraniliprole, flubendiamide-abamectin and penoxsulam exposure were 5.37, 4.90 and 4.68 mg/L; 0.035, 0.025 and 0.021 mg/L; 1.74, 1.45 and 1.29 mg/L, respectively. The safety concentrations (SC) of chlorantraniliprole, flubendiamide-abamectin and penoxsulam to the tadpoles were 1.23, 0.30 and 0.003 mg/L, respectively. Based on these findings, chlorantraniliprole and penoxsulam were moderately toxic, while flubendiamide-abamectin was highly toxic. All pairwise joint toxicity tests showed moderate toxicity. The LC50 values after 24, 48 and 72 h of exposure were 7.08, 6.61 and 6.03 mg/L for chlorantraniliprole+penoxsulam, with corresponding values of 2.455, 2.328 and 2.183 mg/L for chlorantraniliprole+flubendiamide-abamectin, and 1.132, 1.084 and 1.050 mg/L for penoxsulam+flubendiamide-abamectin, with safe concentrations of 1.73, 0.63 and 0.30 mg/L, respectively. For toxic evaluations of pairwise combinations of the three agrochemicals, only the joint toxicity of chlorantraniliprole and flubendiamide-abamectin after 24 h was found to be synergistic, whereas all other tests were antagonistic. Our findings provide valuable information on the toxic effects of agrochemicals on amphibians and how various types of agrochemicals can be reasonably used in agricultural areas.

Effects of light intensity on activity in four sympatric anuran tadpoles

Though light conditions are known to affect the development and anti-predation strategies of several aquatic species, relatively little is known about how different species react to light, or how light can affect these species during different points in their life-cycle. In this study, we used four sympatric anuran tadpoles (Bufo gargarizans, B. melanostictus, Pelophylax nigromaculatus and Microhyla fissipes) as animal system to examine species-specific activities of the underdoing different light intensity treatments, so as to better understand how they respond to light. We exposed four different species of tadpoles to 1660 and 14 lux light intensity treatments and then measured several parameters including development stage, body length and tail length, and as well as their basic activities. The results of this observation and analysis showed that the activities of tadpoles were significantly greater in B. gargarizans and B. melanostictus than in P. nigromaculatus and M. fissipes; and were also significantly greater during times of high light intensity as compared to during low light intensity. Moreover, the observed relationship between species and light intensity was significant. The activities of B. gargarizans and B. melanostictus tadpoles were greater in high light, while the activity of P. nigromaculatus tadpoles was greater in low light intensity, while M. fissipes tadpoles showed no differences in either low or high intensity light. Furthermore, the activities of B. gargarizans, B. melanostictus and M. fissipes tadpoles in terms of developmental stage, body size or tail length did not seem to differ with light intensity, but during early larval developmental period of P. nigromaculatus, the activity of tadpoles was negatively correlated with development stage, but irrelevant to either body size or tail length in different light intensities. These results lead us to conclude the observed activities of the four sympatric anuran tadpoles are closely correlated with their specific anti-predation strategies.

Effects of hydroperiod duration on developmental plasticity in tiger frog (Hoplobatrachus chinensis) tadpoles

While developmental plasticity can facilitate evolutionary diversification of organisms, the effects of water levels as an environmental pressure on tiger frogs remains unclear. This study clarifies the relationship by studying the responses of tiger frog (Hoplobatrachus chinensis) tadpoles to simulated hydroperiods (i.e., constant low water levels, constant high water levels, increasing water levels, decreasing water levels, rapid changes in water levels and gradual fluctuations in water levels) in a laboratory setting. ANOVA analysis showed that none of the water level treatments had any significant effect on the total length, body mass, or developmental stages of H. chinensis tadpoles half way through development (11 days old). Tadpoles raised in rapidly fluctuating water levels had protracted metamorphosis, whereas tadpoles raised under low and gradually fluctuating water levels had shortened metamorphosis. None of the water level treatments had a significant effect on the snout-vent length (SVL) or body mass of H. chinensis tadpoles at Gosner stage 42, or on the body mass of tadpoles at Gosner stage 45. However, the tadpoles raised in high levels and rapidly fluctuating water levels, significantly larger SVL at Gosner stage 45, while ones under gradually fluctuating water levels had smaller SVL than the other groups. Time to metamorphosis was positively correlated with body size (SVL) at metamorphosis in H. chinensis tadpoles. H. chinensis tadpoles under constant low water level had the highest mortality rate among all the treatments (G-test). Moreover, ANOVA and ACNOVA (with body length as the covariate) indicated that water levels had no significant effect on either the morphology (i.e. head length, head width, forelimb length, hindlimb length and body width) or the jumping ability of juvenile H. chinensis. These results suggest that the observed accelerated metamorphosis and high mortality of H. chinensis tadpoles under decreasing water level treatment was driven by density-induced physical interactions among increasing conspecifics.

Self-assembled monolayers of CH3S from the adsorption of CH3SSCH3 on Au(111)

By performing density functional theory calculations, we have examined the adsorption of dimethyl disulfide (CH3SSCH3) on Au(111). In addition, we have also charted the reaction paths leading to dissociation of the S-S bond and the formation of thiolate-adatom species. Further, we have simulated the scanning tunneling microscopic (STM) images of the key adsorption intermediates and products and compared them with the experimental data available in the literature. In summary, our computations show that CH3SSCH3 adsorbs on Au(111) non-dissociatively with a moderate adsorption energy 0.42 eV for the trans-conformation which is 0.24 eV more stable than its cis-isomer. When the adsorbed trans-CH3SSCH3 dissociates at low temperature, the two CH3S fragments are retained by the closest neighboring sites and the trans-conformation of them prior to S-S dissociation can be preserved. The activation barrier to rotating the CH3S fragments on Au(111) is 0.17 eV so a moderate temperature rise can facilitate the transformation of the trans-conformation and generate a mixture of the trans- and cis-conformation. Our calculations also show that intrinsic defects such as gold adatoms (Auad) are active in CH3SSCH3 dissociation in two mechanisms: a direct mechanism in which CH3SSCH3 dissociation drives Auad formation and CH3S-Auad formation simultaneously, with leftover vacancies as by-products; a sequential mechanism in which Auad is present in advance and subsequently interacts with a nearby CH3S fragment to form CH3S-Auad. The respective activation barriers are 0.15 and 0.32 eV for the trans- and cis-CH3S-Auad-SCH3 complex along the direct mechanism, and 0.21 and 0.18 eV along the sequential mechanism.

Band gap engineering of FeS2 under biaxial strain: a first principles study

The band gap increases with increasing tensile strain to its maximum value at 6% strain and then decreases.

Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

We examined sexual size dimorphism (SSD), mating pattern, fertilization efficiency and female reproductive traits in two bufonid toads (Bufo gargarizans and Duttaphrynus melanostictus) to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gar-garizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficiencies on average were higher in B. gargarizans (95%) than in D. melanostictus (91%). Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects: (1) both showed size-assortative mating; (2) females did not tradeoff egg size against egg number; (3) male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length (SVL); and (4) the ratio of male to female SVL did not affect fertilization efficiency. Our data show that: (1) a female preference for large males is likely not important in terms of egg fertilization success; (2) a male preference for large females is likely important because larger females are more fecund; and (3) size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating.

[Method of isolation of intrafusal fibres of muscle spindle in soleus of rats]

Capsule restricts the further study on muscle spindle function and the involved mechanism. The aim of this study was to establish the isolation method of intrafusal fibres from the isolated rat muscle spindle. Intrafusal fibres were harvested from muscle spindle of soleus muscle in rats using neutrase-collagenase digestion. A variety of incubation mediums have been tested to find out an appropriate medium of intrafusal fibers in vitro. Trypan blue staining was used to detect cell death, and patch clamp was used to record resting potential. The results showed that the intrafusal fibres incubated with amine acid-saline solution were almost all dead. DMEM could maintain good condition of the fibres, but excess CO2 ventilation would induce cellular swelling or even death. While Leiboviz's 15 (L-15) medium can guarantee 1-2 h of physiological condition of the intrafusal fibres. Coverslips treated with gelatin, polylysine and serum was the better interfaces for the intrafusal fibres to adhere easily, compared with regularly treated coverslip. The resting potential of intrafusal fibres was (-45.3 ± 5.1) mV, consistent with others obtained from in vivo muscle spindle from cats and frogs. These results suggest that the isolation method of the intrafusal fibres has been successfully established in the present study, providing a new approach in better understanding of muscle spindle activities and the involved mechanism.

Effects of intrinsic defects on methanthiol monolayers on Cu(111): a density functional theory study

Density functional theory calculations were used to examine the effects of intrinsic surface defects of Cu(111) on the adsorption of methylthiol (CH3SH). The examination covers both the initial non-dissociative adsorption and the subsequent dissociation reaction pathways to form intermediate and final reaction products. By comparing the most probable adsorption structures likely formed after the adsorption of CH3SH on Cu(111) with and without the presence of adatoms (Cu(ad)) and vacancies, this computational work offers new insights about the geometry and thermodynamic stability of these structures. Particularly, it reveals a new type of surface complexes having two CH3S bonding to one Cu(ad) (referred therein as CH3S-Cu(ad)-CH3S). In addition, this work also yields new reaction dynamics results on transition states and activation barriers. The results reveal that the presence of Cu(ad) indeed significantly changes the kinetics of adsorption and dissociation of CH3SH on Cu(111). The most kinetically favorable reaction pathway turns out to be that involving the formation of a special surface complex formed by one Cu(ad) plus two CH3S fragments from the dissociation of CH3SH, with the two S atoms located at the bridge sites of Cu(111). Finally, this work also gives simulated scanning tunneling microscopic images for the most important adsorption species in the course of the transition from CH3SH∕Cu(111) to CH3S∕Cu(111), which may stimulate future experimental studies of self-assembled monolayers on practical metal substrates such as thiols on copper.

[Relationship between simulated weightlessness-induced muscle spindle change and muscle atrophy]

One of the most important and urgent issues in the field of space medicine is to reveal the potential mechanism underlying the disused muscle atrophy during the weightlessness or microgravity environment. It will conduce to find out effective methods for the prevention and treatment of muscle atrophy during a long-term space flight. Increasing data show that muscle spindle discharges are significantly altered following the hindlimb unloading, suggesting a vital role in the progress of muscle atrophy. In the last decades, we have made a series of studies on changes in the morphological structure and function of muscle spindle following simulated weightlessness. This review will discuss our main results and related researches for understanding of muscle spindle activities during microgravity environment, which may provide a theoretic basis for effective prevention and treatment of muscle atrophy induced by weightlessness.

Seebeck rectification enabled by intrinsic thermoelectrical coupling in magnetic tunneling junctions

An intrinsic thermoelectric coupling effect in the linear response regime of magnetic tunneling junctions (MTJ) is reported. In the dc response, it leads to a nonlinear correction to Ohm's law. Dynamically, it enables a novel Seebeck rectification and second harmonic generation, which apply for a broad frequency range and can be magnetically controlled. A phenomenological model on the footing of the Onsager reciprocal relation and the principle of energy conservation explains very well the experimental results obtained from both dc and frequency-dependent transport measurements performed up to GHz frequencies. Our work refines previous understanding of magnetotransport and microwave rectification in MTJs. It forms a new foundation for utilizing spin caloritronics in high-frequency applications.

[Electrophysiological characteristics of the isolated muscle spindle in rats]

The aim of this study was to observe the electrophysiological characteristics of the isolated rat muscle spindle. The muscle spindle was isolated from rat soleus and the afferent discharge of the isolated muscle spindle was recorded by air-gap technique. In the basic physiological salt solution, the spontaneous impulses of muscle spindle were at a lower level with irregular intervals. The mean frequency of afferents was (51.78 ± 25.63) impulses/1 000 s (n = 13). The muscle spindle afferents were significantly increased and maintained over time by the addition of certain amino acids during the observation. The number of the action potential recorded per 1 000 s was 200-1 000 [mean: (687.62 ± 312.56) impulses/1 000 s, n = 17]. In addition to the typical propagated action potential, a large number of abortive spikes were observed. The results indicate that the activities of isolated muscle spindles in rats can be well maintained by the addition of certain amino acids. The results initially establish and provide the possibility for further research conducted in isolated rat muscle spindles.

The role of different glutamate receptors in the mediation of glutamate-evoked excitation of red nucleus neurons after simulated microgravity in rat

The present study investigates changes in red nucleus (RN) neuronal activity and the role of glutamate receptors (GluRs) after simulated microgravity (tail-suspension) in the rat using single-unit recording and microinjection. The results showed that tail-suspension for 3, 7, and 14 days could induce a significant decrease in spontaneous firing rate of RN neurons in a time-dependent manner. Unilateral microinjection of glutamate into the RN significantly increased the firing rate of RN neurons, but the increased firing rate was significantly reduced following tail-suspension time. Microinjection of the NMDA receptor antagonist MK-801 or the non-NMDA receptor antagonist DNQX into the RN blocked this excitatory effect induced by glutamate. However, microinjection of the metabotropic glutamate receptor (mGluR) antagonist (+/-)-MCPG into the RN had no effect. These results suggest that simulated microgravity can reduce excitability of RN neurons following a functional impairment of glutamate receptors. NMDA and non-NMDA receptors, but not mGluRs, are involved in the mediation of glutamate-evoked excitation of RN neurons. The decrease in excitability of RN neurons may be involved in simulated microgravity-induced muscle atrophy.

[Epimedium alleviates chemotherapy-induced damage to the ultrastructure and function of rat epididymides]

OBJECTIVE

To investigate the protective action of Epimedium against chemotherapy-induced damage to rat epididymides.

METHODS

Fifty 60-day-old male rats were divided into a control, a model and a treatment group. Procarbazine was injected into the abdominal cavity of the model rats at the dose of 30 mg/(kg x d). In addition to procarbazine, Epimedium was given intragastrically to the treatment group. The changes in the ultrastructure of the epididymis were observed after 10 and 20 days.

RESULTS

Electron microscopy showed that the chemotherapy-induced damages to the epididymal epithelia mainly included cell swelling, local cavitation of mitochondria, tumor-like change in nucleoli, agglutination of marginal translocation of heterochromatin and cell apoptosis. The damage to the epithelial ultrastructure was slight in the treatment group as compared with the model rats. Chemotherapy significantly affected sperm concentration, sperm viability and sialic acid (SA), which were (15.59 +/- 4.01) x 10(6)/ml, (76.71 +/- 10.11)% and (19.38 +/- 9.34) g/mg prot in the model group in comparison with (10.63 +/- 3.82) x 10(6)/ml (P < 0.01), (60.03 +/- 7.54)% (P < 0.01) and (13.62 +/- 7.81) g/g prot (P < 0.05) in the control. Epimedium significantly increased sperm viability in the treatment group (60.03 +/- 7.54)% as compared with the model rats (69.90 +/- 12.58)% (P < 0.05).

CONCLUSION

Epimedium can lessen chemotherapy-induced damage to the epididymis and protect the reproductive function of rats.

[Randomized clinical study of surgery versus radiotherapy alone in the treatment of resectable esophageal cancer in the chest]

OBJECTIVE

To compare the treatment results between radical surgery and late course accelerated hyperfractionated radiotherapy (LCAHFR) for patients with resectable esophageal cancer in the chest.

METHODS

From June 1998 to September 2002, 269 patients with resectable esophageal cancer in the chest were randomized into two groups: 135 in surgery group and 134 in radiotherapy. The surgery group received esophagectomy including resection of the lesion and 5 cm margin at both ends from the lesion as well as surrounding lymph nodes > or = 5 mm and fatty tissue. In the radiotherapy group: irradiation field for the lesion in the upper esophageal cancer included the gross lesion, bilateral supraclavicular nodes and 4 cm of normal esophagus from lower margin of the gross disease; for the esophageal cancer at the middle segment, it included the gross disease with 4 cm normal esophagus from both ends of the lesion; for the lesion in the lower esophageal cancer, it included 4 cm of normal esophagus and the gross lesion as well as the draining gastric lymph nodes. The width of the irradiation field was 5-6 cm. The 90% isodose volume was covered by the entire CTV with 3-5 beams, in a conventionally fractionated RT at 1.8-2.0 Gy/d for the first two thirds of treatment course to a dose of about 50-50.4 Gy followed by LCAHFR using reduced fields (2 cm extended margin at both ends of the lesion) , twice daily at 1.5 Gy per fraction ( with aminimal interval of 6 h between fractions) to a dose of 18-21 Gy. The total dose whole radiotherapy was 68.4-71.0 Gy.

RESULTS

The 1-, 3- and 5-year overall survival rate was 93.3%, 61.5% and 36.9% in the surgery group versus 88.6%, 56.2% and 34.7% in the radiotherapy group without statistical difference between the two groups. The 1-, 3- and 5-year progression free survival rate was 75.9%, 43.7% and 23.1% in the surgery group and 73.3%, 39.7% and 20.6%, respectively, in the radiotherapy group without statistical difference between the two groups either.

CONCLUSION

The results treated by late course accelerated hyperfractionated conformal radiotherapy alone may be comparable to that by radical surgery for patient with resectable esophageal cancer in the chest.

Whole-cell recordings of calcium and potassium currents in acutely isolated smooth muscle cells

AIM: To record calcium and potassium currents in acutely isolated smooth muscle cells of mesenteric arterial branches in rats.

METHODS: Smooth muscle cells were freshly isolated by collagenase digest and mechanical trituration with polished pipettes. Patch clamp technique in whole-cell mode was employed to record calcium and potassium currents.

RESULTS: The procedure dissociated smooth muscle cells without impairing the electrophysiological characteristics of the cells. The voltage-gated Ca²⁺ and potassium currents were successfully recorded using whole-cell patch clamp configuration.

CONCLUSION: The method dissociates smooth muscle cells from rat mesenteric arterial branches. Voltage-gated channel currents can be recorded in this preparation.

Exotic meson decay to omegapi0pi-

A partial-wave analysis of the mesons from the reaction pi(-)p --> pi(+)pi(-)pi(-)pi(0)pi(0)p has been performed. The data show b(1)pi decay of the spin-exotic states pi(1)(1600) and pi(1)(2000). Three isovector 2(-+) states were seen in the omegarho(-) decay channel. In addition to the well known pi(2)(1670), signals were also observed for pi(2)(1880) and pi(2)(1970).

Adsorption of triplet O(2) on Si(100): the crucial step in the initial oxidation of a silicon surface

It has long been understood that a precursor mediated chemisorption is a significant part of the dynamics for the adsorption of O(2) on Si(100), which is a much studied model system of surface reaction with considerable technological relevance. However, theoretical studies on the interaction between O(2) and Si(100) have been focused on the excited singlet state of O2 and unable to explain the observations in surface scattering experiments. We demonstrate by first principles calculations that such a focus is misplaced. In reality, triplet O(2) can also react with Si(100), after overcoming small barriers, and its reaction paths provide a full account for experiments. Our results highlight the important role played by triplet O(2) in surface oxidation.