Bioinspired urchin-like murray carbon nanostructure with protection shell for advanced lithium-sulfur batteries

Commercial application of lithium-sulfur(Li-S) batteries is hindered by the insulating nature of sulfur and the dissolution of polysulfides. Here, a bioinspired 3D urchin-like N-doped Murray's carbon nanostructure(N-MCN) with interconnected micro-meso-macroporous structure and a polydopamine protection shell has been designed as an effective sulfur host for high-performance Li-S batteries. The advanced 3D hierarchically porous framework with the characteristics of the generalized Murray's law largely improves electrolyte diffusion, facilitates electrons/ions transfer and provides strong chemisorption for active species, leading to the synergistic structural and chemical confinement of polysulfides. As a result,the obtained P@S/N-MCN electrode with high areal sulfur loading demonstrates high capacity at high current densities after long cycles. This work reveals that following the generalized Murray's law is feasible to design high-performance sulfur cathode materials for potentially practical Li-S battery applications.

Mn^(4+) activated phosphors in photoelectric and energy conversion devices

Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions,Mn^(4+)ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices such as white light emitting diode(W-LED),plant cultivation LED,and temperature thermometer.Up to now,Mn^(4+)has been widely introduced into the lattices of various inorganic hosts for brightly redemitting phosphors.However,how to correlate the structure-activity relationship between host framework,luminescence property,and photoelectric device is urgently demanded.In this review,we thoroughly summarize the recent advances of Mn^(4+)doped phosphors.Meanwhile,several strategies like co-doping and defect passivation for improving Mn^(4+)emission are also discussed.Most importantly,the relationship between the protocols for tailoring the structures of Mn^(4+)doped phosphors,increased luminescence performance,and the targeted devices with efficient photoelectric and energy conversion efficiency is deeply correlated.Finally,the challenges and perspectives of Mn^(4+)doped phosphors for practical applications are anticipated.We cordially anticipate that this review can deliver a deep comprehension of not only Mn^(4+)luminescence mechanism but also the crystal structure tailoring strategy of phosphors,so as to spur innovative thoughts in designing advanced phosphors and deepening the applications.

Mediating Effect of Perceived Organizational Support on the Resilience and Mental Health of ICU Nurses

Objective:To investigate the mediating effect of organizational support on the relationship between resilience and anxiety-depression-stress by researching ICU nurses.Methods:A total of 675 ICU nurses in Shaanxi Province were surveyed using the organizational support scale,the resilience evaluation scale for medical staff,and the Depression-Anxiety-Stress Scale(DASS-21).Results:The resilience of ICU nurses had significant correlation with the level of organizational support(r=0.448,P<0.01),but was negatively correlated with depression(r=-0.238,P<0.001),anxiety(r=-0.287,P<0.01),and stress(r=-0.213,P<0.01);the level of organizational support of ICU nurses was also negatively correlated with depression(r=-0.452,P<0.01),anxiety(r=-0.410,P<0.01),and stress(r=-0.490,P<0.01).The sense of organizational support played a mediating role between the resilience of ICU nurses and their depression-anxiety-stress,the mediating effect accounted for 78%of the total effect.Conclusion:The perceived organizational support and resilience is an important external protective factor for the mental health and ability of ICU nurses.The management departments should continue to pay attention to the mental health of ICU nurses,take effective measures to improve the sense of organizational support and resilience of nurses,and ensure the good mental health of ICU nurses.

超高稳定性的等级孔碳负载高分散铜基选择性加氢催化剂

负载型Pd,Pt,Au等贵金属催化剂由于具有较高活性而被广泛应用于选择性加氢催化领域,但资源稀缺、价格昂贵等问题严重制约了其在催化领域的长远发展.目前大量研究结果表明,非贵金属催化剂也具有较高的选择性催化加氢能力,在已被报道的非贵金属加氢催化剂中,铜基催化剂由于在选择性加氢反应中表现出较高加氢选择性和活性引起了人们的广泛关注.然而,早期研究的负载型铜基催化剂普遍存在催化稳定性较低的问题,所以提高铜基催化剂的使用寿命成为了问题关键.本文以铜基有机金属框架HKUST-1作为合成目标催化剂的前驱体,首先探究了水热合成条件对HKUST-1合成结构完整性及结晶度的影响,再通过精确调控HKUST-1的原位碳化过程,利用金属有机框架高温分解自还原行为,成功制备出了等级孔碳负载的高分散铜基催化剂,并将所制备的催化剂应用于1,3-丁二烯选择性加氢反应中.扫描电子显微镜、高分辨透射电子显微镜、X射线衍射、氮气吸脱附、傅里叶红外吸收光谱、X射线光电子能谱等技术用来表征了碳化前后催化剂载体结构的变化,铜粒子尺寸、价态及其在载体中分布的变化.文中也深入探究了以上因素对催化剂选择性催化加氢性能的影响.研究表明:120℃水热合成18 h能获得尺寸在15μm左右,结晶度高且形貌规整的HKUST-1前驱体.随后通过合理地控制金属有机框架分解过程,可实现对碳载体的等级孔结构和活性铜纳米粒子的分散程度的精确调控,获得高效等级孔载体结构和高分散铜位点的催化剂.不仅如此,通过一步碳化自还原HKUST-1制备的等级孔碳负载Cu的催化性能表现出对碳化温度高度的关联性.其催化活性随碳化处理温度的升高呈现先增强后减弱的趋势,但所有获得的催化剂对单烯烃都具有很高的选择性(>98%).特别地,本文发现在600℃碳化合成的催化剂在低温75℃反应可实现对1,3-丁二烯的100%转化,对丁烯的选择性为100%.同时,该催化剂在恒温75℃下持续反应120 h以上,其对丁二烯转化率和对丁烯选择性依然保持100%,表现出了超高的催化稳定性和潜在的商用价值.本文展示了通过简单地调控金属有机骨架的碳化过程是获得具有优异选择性催化加氢性能的铜基催化剂的有效途径.

Effects of probiotics on nonalcoholic fatty liver disease:A meta-analysis

AIM:To investigate the relationship between the gutliver axis and nonalcoholic fatty liver disease(NAFLD),we performed a meta-analysis to evaluate the effects of probiotic therapy in NAFLD.METHODS:We searched PubMed,Medline,Embase,Web of Science,the Cochrane Library and Chinese Biomedicine Database for all relevant randomized controlled trials on probiotics in patients with NAFLD/nonalcoholic steatohepatitis(NASH).A statistical analysis was performed using RevMan 5.0 software.RESULTS:Four randomized trials involving 134 NAFLD/NASH patients were included.The results showed that probiotic therapy signifcantly decreased alanine aminotransferase(ALT),aspartate transaminase(AST),total-cholesterol(T-chol),high density lipoprotein(HDL),tumor necrosis factor(TNF)-αand homeostasis model assessment of insulin resistance(HOMAIR)[ALT:weighted mean difference(WMD)-23.71,95%CI:-33.46--13.95,P<0.00001;AST:WMD-19.77,95%CI:-32.55--7.00,P=0.002;T-chol:WMD-0.28,95%CI:-0.55--0.01,P=0.04;HDL:WMD-0.09,95%CI:-0.16-0.01,P=0.03;TNF-α:WMD-0.32,95%CI:-0.48--0.17,P<0.0001;HOMA-IR:WMD-0.46,95%CI:-0.73--0.19,P=0.0008].However,the use of probiotics was not associated with changes in body mass index(BMI),glucose(GLU)and low density lipoprotein(LDL)(BMI:WMD 0.05,95%CI:-0.18-0.29,P=0.64;GLU:WMD 0.05,95%CI:-0.25-0.35,P=0.76;LDL:WMD-0.38,95%CI:-0.78-0.02,P=0.06).CONCLUSION:Probiotic therapies can reduce liver aminotransferases,total-cholesterol,TNF-αand improve insulin resistance in NAFLD patients.Modulation of the gut microbiota represents a new treatment for NAFLD.

Serum cystatin C levels are negatively correlated with post-stroke cognitive dysfunction

Stroke is the leading cause of death and long-term disability worldwide,and cognitive impairment and dementia are major complications of ischemic stroke.Cystatin C (CysC) has been found to be a neuroprotective factor in animal studies.However,the relationship between CysC levels and cognitive dysfunction in previous studies has revealed different results.This prospective observational study investigated the correlation between serum CysC levels and post-stroke cognitive dysfunction at 3 months.Data from 638 patients were obtained from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS).Cognitive dysfunction was assessed using the Mini-Mental State Examination (MMSE) at 3 months after stroke.According to the MMSE score,308 patients (52.9%) had post-stroke cognitive dysfunction.After adjusting for potential confounding factors,the odds ratio (95% CI) of post-stroke cognitive dysfunction for the highest quartile of serum CysC levels was 0.54 (0.30–0.98),compared with the lowest quartile.The correlation between serum CysC and cognitive dysfunction was modified by renal function status.We observed a negative linear dose-response correlation between CysC and cognitive dysfunction in patients with normal renal function (Plinearity = 0.044),but not in those with abnormal renal function.Elevated serum CysC levels were correlated with a low risk of 3-month cognitive dysfunction in patients with acute ischemic stroke,especially in those with normal renal function.The current results suggest that CysC is a protective factor for post-stroke cognitive dysfunction,and could be used to treat post-stroke cognitive dysfunction.The CATIS study was approved by the Institutional Review Boards at Soochow University from China (approval No.2012-02) on December 30,2012,and was registered at ClinicalTrials.gov (identifier No.NCT01840072) on April 25,2013.

Double-balloon enteroscopy in small bowel tumors: A Chinese single-center study

AIM: To analyze the clinical characteristics of small bowel tumors detected by double-balloon enteroscopy (DBE) and to evaluate the diagnostic value of DBE in tumors. METHODS: Four hundred and forty consecutive DBE examinations were performed in 400 patients (250 males and 150 females, mean age 46.9 ± 16.3 years, range 14-86 years) between January 2007 and April 2012. Of these, 252 patients underwent the antegrade approach, and 188 patients underwent the retrograde approach. All the patients enrolled in our study were suspected of having small bowel diseases with a negative etiological diagnosis following other routine examinations, such as upper and lower gastrointestinal endoscopy and radiography tests. Data on tumors, such as clinical information, endoscopic findings and opera-tion results, were retrospectively collected. RESULTS: Small bowel tumors were diagnosed in 78 patients, of whom 67 were diagnosed using DBE, resulting in a diagnostic yield of 16.8% (67/400); the other 11 patients had negative DBE findings and were diagnosed through surgery or capsule endoscopy. Adenocarcinoma (29.5%, 23/78), gastrointestinal stromal tumor (24.4%, 19/78) and lymphoma (15.4%, 12/78) were the most common tumors. Among the 78 tumors, 60.3% (47/78) were located in the jejunum, and the overall number of malignant tumors was 74.4% (58/78). DBE examinations were frequently performed in patients with obscure gastrointestinal bleeding (47.4%) and abdominal pain (24.4%). The positive detection rate for DBE in the 78 patients with small bowel tumors was 85.9% (67/78), which was higher than that of a computed tomography scan (72.9%, 51/70). Based on the operation results, the accuracy rates of DBE for locating small bowel neoplasms, such as adenocarcinoma, gastrointestinal stromal tumor and lymphoma, were 94.4%, 100% and 100%, respectively. The positive biopsy rates for adenocarcinoma and lymphoma were 71.4% and 60%, respectively. CONCLUSION: DBE is a useful diagnostic tool with high clinical practice value and should be considered the gold standard for the investigation of small bowel tumors.

Diagnostic accuracy of endoscopic ultrasonography for rectal neuroendocrine neoplasms

AIM:To investigate the diagnostic accuracy of endoscopic ultrasonography(EUS)for rectal neuroendocrine neoplasms(NENs)and the differential diagnosis of rectal NENs from other subepithelial lesions(SELs).METHODS:The study group consisted of 36 consecutive patients with rectal NENs histopathologically diagnosed using biopsy and/or resected specimens.The control group consisted of 31 patients with homochronous rectal non-NEN SELs confirmed by pathology.Epithelial lesions such as cancer and adenoma were excluded from this study.One EUS expert blinded to the histological results reviewed the ultrasonic images.The size,original layer,echoic intensity and homogeneity of the lesions and the perifocal structures were investigated.The single EUS diagnosis recorded by the EUS expert was compared with the histological results.RESULTS:All NENs were located at the rectum 2-10 cm from the anus and appeared as nodular(n=12),round(n=19)or egg-shaped(n=5)lesions with a hypoechoic(n=7)or intermediate(n=29)echo pattern and a distinct border.Tumors ranged in size from 2.3 to 13.7 mm,with an average size of 6.8 mm.Homogeneous echogenicity was seen in all tumors except three.Apart from three patients(stage T2 in two and stage T3 in one),the tumors were located in the second and/or third wall layer without involvement of the fourth and fifth layers.In the patients with stage T1 disease,the tumors were located in the second wall layer only in seven cases,the third wall layer only in two cases,and both the second and third wall layers in27 cases.Approximately 94.4%(34/36)of rectal NENs were diagnosed correctly by EUS,and 74.2%(23/31)of other rectal SELs were classified correctly as nonNENs.Eight cases of other SELs were misdiagnosed as NENs,including two cases of inflammatory lesions and one case each of gastrointestinal tumor,endometriosis,metastatic tumor,lymphoma,neurilemmoma,and hemangioma.The positive predictive value of EUS for rectal NENs was 80.9%(34/42),the negative predictive value was 92.0%(23/25),and the diagnostic accuracy was85.1%.CONCLUSION:EUS has satisfactory diagnostic accuracy for rectal NENs with good sensitivity,but unfavorable specificity,making the differential diagnosis of NENs from other SELs challenging.

First proof-of-principle experiment with the post-accelerated isotope separator on-line beam at BRIF:measurement of the angular distribution of ^(23)Na+^(40)Ca elastic scattering

The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei.The development of rare isotope accelerators offers opportunities for such studies.To date,many relevant measurements have been performed at accelerators using the projectile fragmentation technique,while the measurements at accelerators using isotope separator on-line(ISOL)systems are still quite scarce.In this work,we present the first proof-of-principle experiment with a post-accelerated ISOL beam at the Beijing Radioactive Ion Beam Facility(BRIF)by measuring the angular distribution of elastic scattering for the stable nucleus^(23)Na from the doubly magic nucleus^(40)Ca at energies above the Coulomb barrier.The angular distribution measured by a silicon strip detector array in a scattering chamber using the ISOL beam at BRIF is in good agreement with that measured by the high-precision Q3 D magnetic spectrograph using the nonISOL beam at nearly the same energy.This work provides useful background for making BRIF a powerful tool for the investigation of the reaction dynamics of exotic nuclei.

Clonal immunoglobulin heavy chain and T-cell receptor γ gene rearrangements in primary gastric lymphoma

AIM:To study the diagnostic value of immunoglobulin heavy chain(IgH)and T-cell receptorγ (TCR-γ)gene monoclonal rearrangements in primary gastric lymphoma(PGL).METHODS:A total of 48 patients with suspected PGL at our hospital were prospectively enrolled in this study from January 2009 to December 2011.The patients were divided into three groups(a PGL group,a gastric linitis plastica group,and a benign gastric ulcer group)based on the pathological results(gastric mucosal specimens obtained by endoscopy or surgery)and follow-up.Endoscopic ultrasonography(EUS)and EUSguided biopsy were performed in all the patients.The tissue specimens were used for histopathological examination and for IgH and TCR-γ gene rearrangement polymerase chain reaction analyses.RESULTS:EUS and EUS-guided biopsy were successfully performed in all 48 patients.In the PGL group(n=21),monoclonal IgH gene rearrangements were detected in 14(66.7%)patients.A positive result for each set of primers was found in 12(57.1%),8(38.1%),and 4(19.0%)cases using FR1/JH,FR2/JH,and FR3/JH primers,respectively.Overall,12(75%)patients with mucosal-associated lymphoid tissue lymphoma(n=16)and 2(40%)patients with diffuse large B-cell lymphoma(n=5)were positive for monoclonal IgH gene rearrangements.No patients in the gastric linitis plastica group(n=17)and only one(10%)patient in the benign gastric ulcer group(n=10)were positive for a monoclonal IgH gene rearrangement.No TCRgene monoclonal rearrangements were detected.The sensitivity of monoclonal IgH gene rearrangements was 66.7%for a PGL diagnosis,and the specificity was96.4%.In the PGL group,8(100%)patients with stage IIE PGL(n=8)and 6(46.1%)patients with stage IE PGL(n=13)were positive for monoclonal IgH gene rearrangements.CONCLUSION:IgH gene rearrangements may be associated with PGL staging and may be useful for the diagnosis of PGL and for differentiating between PGL and gastric linitis plastica.

Large heterotopic gastric mucosa and a concomitant diverticulum in the rectum:Clinical experience and endoscopic management

Heterotopic gastric mucosa(HGM) in the rectum is an extremely rare clinical entity which may be missed or misdiagnosed due to a lack of knowledge.In the present study,a 14-year-old girl visited our hospital due to a 5-year history of repeated hematochezia.Colonoscopy showed a solitary superficial depressed lesion approximately 5 cm in size and a concomitant 1.5 cm deep diverticulum in the rectum.Histological examination of the endoscopic biopsy showed typical ectopic gastric mucosa in the depressed lesion and inside the diverticulum.Narrow band imaging further confirmed the histological results.Endoscopic ultrasound indicated that the lesion originated from the mucosal layer,and partially involved the submucosal layer.Endoscopic submucosal dissection was performed in this patient due to the large size and shape of the lesion.No bleeding,perforation or other adverse events were observed.The presence of HGM in the diverticular cavity greatly increased the surgical difficulty.A literature review was also carried out in our study.

Interwoven scaffolded porous titanium oxide nanocubes/carbon nanotubes framework for high-performance sodium-ion battery

Supercapacitor-like Na-ion batteries have attracted much attention due to the high energy density of batteries and power density of capacitors.Titanium dioxide(TiO_(2)),is a promising anode material.Its performance is however seriously hindered by its low electrical conductivity and the sluggish diffusion of sodium ions(Na^(+))in the TiO_(2)matrix.Herein,this work combines porous TiO_(2)nanocubes with carbon nanotubes(CNTs)to enhance the electrical conductivity and accelerate Na^(+)diffusivity for Na-ion batteries(NIBs).In this composite,an interwoven scaffolded TiO_(2)/CNTs framework is formed to provide abundant channels and shorter diffusion pathways for electrons and ions.The in-situ X-ray diffraction and cyclic voltammetry confirm the low strain and superior transport kinetics in Na^(+)intercalation/extraction processes.In addition,the chemically bonded TiO_(2)/CNTs hybrid provides a more feasible channel for Na^(+)insertion/extraction with a much lower energy barrier.Consequently,the TiO_(2)/CNTs composite exhibits excellent electrochemical performance with a capacity of 223.4 m Ah g^(-1)at 1 C and a capacity of 142.8 m Ah g^(-1)at 10 C(3.35 A g^(-1)).The work here reveals that the combination of active materials with CNTs can largely improve the utilization efficiency and enhance their sodium storage.

Analytical solutions for constant-rate test in bounded confined aquifers with non-Darcian effect

This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical modelling for the pumping-induced flow in aquifers with different boundaries is developed by employing image-well theory with the superposition principle,of which the non-Darcian effect is characterized by Izbash’s equation.The solutions are derived by Boltzmann and dimensionless transformations.Then,the non-Darcian effect and wellbore storage are especially investigated according to the proposed solution.The results show that the aquifer boundaries have non-negligible effects on pumping,and ignoring the wellbore storage can lead to an over-estimation of the drawdown in the first 10 minutes of pumping.The higher the degree of non-Darcian,the smaller the drawdown.

Gastric metastasis presenting as submucosa tumors from renal cell carcinoma:A case report

BACKGROUND Gastric metastasis from renal cell carcinoma(RCC) is an extremely rare clinical entity.Due to an easily neglected RCC history,nonspecific symptoms and underrecognized endoscopic presentation may lead to a potential diagnostic pitfall in daily clinical practice.CASE SUMMARY We present a case of metastatic gastric tumors arising from RCC 5 years after radical nephrectomy.Simultaneous,multifocal metastases to the gallbladder,pancreas and soft tissue were observed.One year previously,a solitary submucosal discoid tumor with a central depression was detected in the gastric fundus in a 65-year-old man.Endoscopic ultrasonography(EUS) showed a 1.12 x 0.38 cm lesion originating from the deeper mucosal layers with partially discontinuous submucosa.One year later,the endoscopic findings of the lesion showed various changes.A large lesion of the protruding type(2.5 cm × 2 cm) was found in the fundus at the same location.EUS showed a heterogeneous mass that involved the mucosa and submucosal layer.In addition,two small similar submucosal lesions 0.4-0.6 cm in size were detected.These lesions had a central depression,surface mucosal congestion and thickened vessels.The two adjacent lesions in the fundus were resected by endoscopic submucosal dissection.Based on the postoperative pathological analysis,the patient was diagnosed with gastric metastasis from RCC.CONCLUSION Gastric metastasis from RCC should be considered in patients with a history of RCC irrespective of the time interval involved.

双功能Cu-TiO_(2)/CuO光催化剂用于大规模协同处理含有机污染物和重金属离子的废水

大多数所制备的光催化剂通常只用于单一地降解有机污染物或还原Cr(VI)的光催化.然而,无机和有机污染物通常共存于工业污水中.同时消除混合的无机和有机污染物仍然存在着巨大的挑战.在本文中,我们通过原位掺杂和异质结工程策略,制备出了新型的双功能CuTiO_(2)/CuO光催化剂用于大规模高效协同光催化消除废水中的有机污染物和过渡金属离子.具体而言,这种双功能光催化剂在RhB和Cr(VI)共存溶液中的光催化RhB降解率和Cr(VI)还原率分别是在单一RhB或Cr(VI)污染物溶液中对应值的2.35和3.84倍.光催化染料分子降解和Cr(VI)还原之间存在显著增强的协同效应.此外,该双功能光催化剂在大规模光催化消除混合污染物方面也表现出较好的活性和稳定性.理论计算表明,铜掺杂和异质结工程促进了高效的光吸收、增高的载流子密度以及快速的光生载流子转移,从而产生高效的协同光催化作用.这种双功能光催化剂的概念为大规模工业废水处理和净化开辟了新途径.

Three-dimensionally ordered macroporous materials for pollutants abatement,environmental sensing and bacterial inactivation

Owing to their facile reactants migration channels,large surface area,maximized exposure of reaction sites and efficient light utilization,three-dimensionally ordered macroporous(3DOM)materials have been extensively adopted in environmental fields such as pollutants removal,environmental detection as well as bacterial disinfection.In this review,the up-to-date 3DOM materials,the corresponding synthesis protocols and the related environmental applications involving photo/electrocatalytic pollutants decomposition,thermocatalytic volatile organic compounds(VOCs)elimination,hazardous substances sensing and bacteria inactivation are completely presented.Simultaneously,the inherent advantages and mechanisms of 3DOM materials in different environmental utilization are thoroughly demonstrated and summarized.Furthermore,the improved performance of environmental applications and the methods of fabricating 3DOM materials are correlated in depth,being favorable for readers to obtain the fundamental knowledge and to motivate some innovative thoughts for modifying 3DOM materials with further elevated environmental remediation capability.Finally,the current difficulties and prospects of 3DOM materials for large-scale and commercial applications are outlooked.This critical review is anticipated to promote the optimization of 3DOM materials and to ripen the related environmental remediation techniques.

TNF-αTNFR1 Signaling is Required for the Full Expression of Acute and Chronic Itch in Mice via Peripheral and Central Mechanisms

Increasing evidence suggests that cytokines and chemokines play crucial roles in chronic itch. In the present study, we evaluated the roles of tumor necrosis factor-alpha （TNF-c0 and its receptors TNF receptor subtype-I （TNFR1） and TNFR2 in acute and chronic itch in mice. Compared to wild-type （WT） mice, TNFRl-knockout （TNFR1-KO） and TNFR1/R2 double-KO （DKO）, but not TNFR2-KO mice, exhibited reduced acute itch induced by compound 48/80 and chloroquine （CQ）. Application of the TNF-synthesis inhibitor thalidomide and the TNF-at antagonist etanercept dose-dependently suppressed acute itch. Intradermal injection of TNF-α was not sufficient to evoke scratching, but potentiated itch induced by compound 48/80, but not CQ. In addition, compound 48/80 induced TNF-α mRNA expression in the skin, while CQ induced its expression in the dorsal root ganglia （DRG） and spinal cord. Furthermore, chronic itch induced by dry skin was reduced by administration of thalidomide and etaner- cept and in TNFR1/R2 DKO mice. Dry skin induced TNF- expression in the skin, DRG, and spinal cord and TNFR1 expression only in the spinal cord. Thus, our findings suggest that TNF-c^-fNFR1 signaling is required for the full expression of acute and chronic itch via peripheral and central mechanisms, and targeting TNFR1 may be benefi- cial for chronic itch treatment.

Antioxidants Attenuate Acute and Chronic Itch:Peripheral and Central Mechanisms of Oxidative Stress in Pruritus

Itch（pruritus） is one of the most disabling syndromes in patients suffering from skin, liver, or kidney diseases. Our previous study highlighted a key role of oxidative stress in acute itch. Here, we evaluated the effects of antioxidants in mouse models of acute and chronic itch and explored the potential mechanisms. The effects of systemic administration of the antioxidants N-acetyl-Lcysteine（NAC） and N-tert-butyl-a-phenylnitrone（PBN）were determined by behavioral tests in mouse models of acute itch induced by compound 48/80 or chloroquine, and chronic itch by treatment with a mixture of acetonediethyl-ether-water. We found that systemic administration of NAC or PBN significantly alleviated compound 48/80-and chloroquine-induced acute itch in a dose-dependent manner, attenuated dry skin-induced chronic itch, and suppressed oxidative stress in the affected skin.Antioxidants significantly decreased the accumulation of intracellular reactive oxygen species directly induced by compound 48/80 and chloroquine in the cultured dorsal root ganglia-derived cell line ND7-23. Finally, the antioxidants remarkably inhibited the compound 48/80-induced phosphorylation of extracellular signal-regulated kinase in the spinal cord. These results indicated that oxidative stress plays a critical role in acute and chronic itch in the periphery and spinal cord and antioxidant treatment may be a promising strategy for anti-itch therapy.

二硫化锡纳米颗粒嵌入二维多孔碳纳米片中间层用于快充锂硫电池

本文报道了将小尺寸二硫化锡(SnS_(2))纳米颗粒嵌入到二维多孔碳纳米片(PCN)中间层,形成多功能纳米复合材料(PCN-SnS_(2))作为硫正极载体,从而降低穿梭效应,实现锂硫电池快充.一方面,复合材料中石墨化碳纳米片可整体性提高电极的导电性.另一方面,复合材料丰富的孔道既促进离子转移和电解质的渗透,又缓解充放电过程中的体积变化,从而确保电极材料的完整性.特别地,PCN的物理限域和小尺寸SnS_(2)纳米颗粒的强化学吸附协同作用可有效降低多硫化物的穿梭效应.因此,PCN-SnS_(2)-S电极具有良好的电化学性能,即使在2 C的高电流密度下,150圈循环后仍可维持650 mA h g^(-1)的放电容量.本研究工作为小尺寸SnS_(2)纳米结构更利于捕获多硫化物以减弱锂硫电池的穿梭效应提供了理论基础.

45#钢支座的液态模锻制备工艺及组织性能分析

目的:以45#钢支座为典型制件对钢质液态模锻制备工艺过程进行分析与优化。研究不同工艺参数对制件组织性能的影响,对制件不同位置的组织性能进行探讨,优化和改善液态模锻钢制制件性能,为钢制制件的液态模锻制备提供理论依据。创新点:1.利用数值模拟软件模拟分析了钢质液态模锻工艺过程,为试验分析提供理论依据;2.对制件不同位置的组织性能分析,探讨了塑性变形在液态模锻工艺过程中的影响。方法:1.采用Pro CAST模拟软件对45#钢液态模锻的凝固过程、温度场及应力场的变化进行模拟(图6~8),并对液态模锻工艺过程进行理论优化;2.采用单一变量法,讨论浇注温度和保压时间对成型件的微观结构、机械性能和耐磨性的影响(图9~12);3.研究成型制件不同位置的微观组织、力学性能和断裂行为(图14,16和17),并讨论液态模锻工艺过程中塑性变形对制件组织性能的影响;4.探讨分析45#钢支座的动态成形工艺(图18),并研究45#钢的液态模锻整体工艺过程。结论:1.熔融金属的最佳浇注温度和保压时间分别在1540~1560℃和35~40s。2.在浇注温度为1540℃和保压时间为35s时,液态锻造制备的45#钢支座具有最佳的组织性能;此时支座盘边缘的抗拉强度、伸长率、维氏硬度和摩擦系数分别为783.4 MPa、17.1%、242.7和0.36。3.45#钢支座不同位置的组织性能差异不大,但由于塑性变形的原因,中间位置的性能表现优于边缘位置。4.45#钢支座的液态锻造工艺过程相对较复杂,包含不同的金属液对流和塑性变形;这些特殊的过程导致45#钢支座的组织性能相对优异。