Investigation on thermal characteristics and desensitization mechanism of improved step ladder-structured nitrocellulose

Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas generators.However,its high mechanical sensitivity caused many accidents during its storage and usage in ammunition.In this work,two kinds of insensitive step ladderstructured nitrocellulose(LNC)with different nitrogen contents were synthesized.The products were characterized by FT-IR,Raman,XRD,SEM,elemental analysis,TGA,DSC,accelerating rate calorimeter analysis(ARC),and drop weight test to study their molecular structure,thermal characteristics and desensitization performance.Compared with raw nitrocellulose,LNC has a sharper exothermic peak in the DSC and ARC curves.The H50values of the two kinds of LNC increased from 25.76 to 30.01 cm for low nitrogen content and from 18.02 to 21.84 cm for high nitrogen content,respectively.The results show that the ladder-structure of LNC which provides regular molecular arrangement and a soft buffer made with polyethylene glycol could affect the energy releasing process of LNC and reduce the sensitivity of LNC.Insensitive LNC provides an alternative to be used as a binder in insensitive propellants formulation.

Establishment and verification of theβ_(2)-AR desensitization asthma mice

Objective:To establish and verify aβ_(2)-AR desensitization asthma mice model.Methods:A total of 30 SPF male BALB/c mice were randomly divided into blank group,the common asthma group,andβ_(2)-AR desensitization asthma model group.Asthma model was established,and on this basis,the method of atom-izing inhalation and intraperitoneal injections of salbutamol was used to prepareβ_(2)-AR desensitization asthma model.After the last stimulation on the 21st day of modeling,the airway resistance of mice was measured.ELISA was used to detect the content of serum IgE;HE staining was used to observe the lung organization degree of infla-mmatory cell infiltration;Western blot method was used to detect theβ_(2)-AR content in lung tissue,RT-PCR was used to detect theβ_(2)-ARmRNA expressionin lung tissue.Results:Compared with the blank group,as acetyl choline(Mch)levels increased,groups of OVA induced airway resistance increases;but theβ_(2)-AR desensitization asthma model group increased airway resistance was more significant(P<0.05);compared with the blank group,IgE levels of common asthma group andβ_(2)-AR desensitization asthma model group elevated(P<0.01).The pathological histology observation found theβ_(2)-AR desensitization asthma airway inflammation infiltration in mice,the excessive mucus secretion and collagen deposition,and the pathological performance obviously increase compared with the common asthma group;β_(2)-AR content in the lung tissue ofβ_(2)-AR desensitization asthma model in mice,β_(2)-AR mRNA expression level in the blank group and common asthma model group were significantly decreased(P<0.05).Conclusion:Theβ_(2)-AR desensitization asthma mouse model was successfully established,and the buildingcycle was short.

A comparison of desensitization methods: Rituximab with/without plasmapheresis in ABO-incompatible living donor liver transplantation

Background: Plasmapheresis is a desensitization method used prior to ABO-incompatible(ABO-I) living donor liver transplantation. However, studies on its usefulness in the rituximab era are lacking.Methods: Fifty-six adult patients underwent ABO-I living donor liver transplantation between January2012 and October 2015. A single dose of rituximab(300 mg/m~2) was administered 2 weeks before surgery with plasmapheresis in all patients until February 2014(RP group, n = 26). Patients were administered rituximab only, without plasmapheresis between March 2014 and October 2015(RO group, n = 30).Results: The 6-, 12-and 18-month overall survival rates were 92.3%, 80.8% and 76.9% in the RP group and 96.6%, 85.4% and 85.4% in the RO group, respectively(P = 0.574). When the initial isoagglutinin titers < 16, neither group showed a rebound rise of isoagglutinin titers. For patients with initial isoagglutinin titers ≥ 16, the rebound rise of isoagglutinin titers was more prominent in the RP group. There was no difference in time-dependent changes in B cell subpopulations and ABO-I-related complications.Conclusions: Sufficient desensitization for ABO-I living donor liver transplantation can be achieved using rituximab alone. This desensitization strategy does not affect the isoagglutinin titers, ABO-I-related complications and patient survival.

Influence of an emulsifier on the pressure desensitization of emulsion explosives

The desensitization degree of emulsion explosives （EE） was calculated with the peak pressure of explosion shock waves tested in water. To an explosive, the less the desensitization degree, the better the compression resistance, so the compression resistance of an explosive can be compared and analyzed quantificationally with the desensitization degree. The influence of an emulsifier on the pressure desensitization of EE was studied, including the content and category of emulsifiers. Three kinds of emulsifiers （Span-80, compound emulsifier, and T-152） were used in the tests. The experimental results show that both the content and category of emulsifiers make a great effect on the pressure desensitization of EE. The desensitization degree of EE reduces with the emulsifier content being increased, but there is an optimal content of an emulsifier for the compression resistance of EE. While the content of Span-80 reaches 4wt%, the desensitization degree of EE becomes a minimal value, and augments somewhat if the emulsifier content is increased more. That is to say, the compression resistance of EE becomes the highest while the content of Span-80 is 4wt%, and the compression resistance will decline if the content of Span-80 is increased more. The compression resistance of the explosive emulsified by compound emulsifier is the highest among all the explosives, when the content of the whole components and manufacturing engineering are kept invariable.

Abstinence Following a Motivation-Skill-Desensitization-Mental Energy Intervention for Heroin Dependence: A Three-year Follow-up Result of a Randomized Controlled Trial

The high rate of relapse among heroin users remains a significant public concern in China. In the present study, we utilized a Motivation-Skill-Desensitization-Mental Energy (MSDE) intervention and evaluated its effects on abstinence and mental health. Eighty-nine male heroin users in a drug rehabilitation center were enrolled in the study. The participants in the MSDE intervention group (n=46) received MSDE intervention, which included motivational interviewing, coping skills training, eye movement desensitization and reprocessing, and mindfulness-based psychotherapy. The participants in the control group (h=43) received a series of lectures on skills training. A significant increase in Contemplation Ladder score (P<0.001) and decreases in scores on the Obsessive Compulsive Drug Use Scale (P<0.001), Beck Depression Inventory (P<0.001), and Aggression Questionnaire (P=O.O33) were found immediately after intervention. Compared to the control group, the MSDE intervention group reported significantly higher abstinence rates (P=0.027) and retention rates (P<0.001) at follow-up. Overall, the MSDE intervention, which uses a combined strategy for relapse prevention, could be a promising approach for preventing relapse among heroin users in China.

EFFECTS OF DESENSITIZATION AND REBOUND TO ADENOSINE ON ACTION POTENTIAL AND CONTRACTILITY IN ATRIAL CELLS IN GUINEA-PIGS

Objective To investigate the effects of desensitization and rebound to adenosine(Ado) on action potential duration(APD) and contractility in guinea-pig atrial cells. Methods Electrical activity was recorded using standard intracellular microelectrode technique and contractility was recorded using. We studied the effects of adenosine on the action potential and desensitization of contractility and rebound of contractility. Results The results showed that action potential duration were shortened by 1,10, 100μ mol·L -1Ado, the ratio of shortened APD was ( 9.58± 1.40)%,(13.80±2.26)%,(24.80±3.19)%, respectively. 1 μ mol·L -1Ado had no desensitization ( P >0.05), but the time of desensitization of 10μ mol·L -1 Ado and 100μ mol·L -1 Ado was 1 minute( P <0.05) and 5 minutes( P < 0.05), respectively. The desensitization of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility was changed from (31.4± 16.04)%(2 minutes) to (50.60±15.87)% (4 minutes), compared with control. After washing out Ado, contractility was shown to rebound, the ratio of increase of contractility by 1,10,100 μ mol·L -1 Ado was (12.38±7.50)%,(19.00± 8.14)% and (27.60±13.44)%, respectively. Conclusion Ado can abbreviate APD in atrial cells. The desensitization of Ado on APD is characterized by concentration-dependent and time-dependent in atrial cells, and the desensitization of contractility of Ado is obvious and contractility was shown to rebound after washing out Ado.

DESENSITIZATION OF ACETYLCHOLINE ON THE INHIBITION EFFECTS OF BLOOD PRE SSURE IN ANESTHETIZED CANINE

Objective To investigate the desensitization of acetylcholine (ACh) on the inhibition effects of blood pressure (BP) in anesthe tized canine and build a model for studying desensitization in vivo. Methods Through changing the intervals (120, 100, 80, 60, 40, 20 seconds) of twice ACh administration (each was 15μg·kg -1,i.v.), the desensitization on the effect of systemic blood pressure of the first ACh in jection towards the subsequent ACh administration was observed. Results When ACh administration intervals were 40, 60, 80 , 100 seconds, the percentages of desensitization of ACh on systemic blood press ure were significantly increased (P<0.05). However, as the intervals were 20 and 120 seconds, the effects of twice ACh administration had no significant dif ference (P>0.05). Conclusion The results indicated that ACh contents in blo od might influence the action of next ACh administration. To some extent, the hi gher the concentration of ACh in blood, the bigger the ratio of desensitization of exogenous ACh is. In addition, this method of twice drug administration could be used as a model of studying desensitization in vivo.

Desensitization of G-protein-coupled receptors induces vascular hypocontractility in response to norepinephrine in the mesenteric arteries of cirrhotic patients and rats

BACKGROUND: The increased β-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric arteries of cirrhotic patients and rats. The present study is to investigate the machinery changes of α-adrenergic receptors and G proteins and their roles in the contractility of mesenteric arteries of cirrhotic patients and animal models. METHODS: Patients with cirrhosis due to hepatitis B and cirrhotic rats induced by CCl 4 were studied. Mesenteric artery contractility in response to norepinephrine was determined by a vessel perfusion system. The contractile effect of G protein-coupled receptor kinase-2 (GRK-2) inhibitor on the mesenteric artery was evaluated. The protein expression of the α 1 adrenergic receptor, G proteins, β-arrestin-2, GRK-2 as well as the activity of Rho associated coiled-coil forming protein kinase-1 (ROCK-1) were measured by Western blot. In addition, the interaction of α 1 adrenergic receptor with β-arrestin-2 was assessed by co-immunoprecipitation. RESULTS: The portal vein pressure of cirrhotic patients and rats was significantly higher than that of controls. The doseresponse curve to norepinephrine in mesenteric arteriole was shifted to the right, and EC 50 was significantly increased in cirrhotic patients and rats. There were no significant differences in the expressions of the α 1 adrenergic receptor and G proteins in the cirrhotic group compared with the controls. However, the protein expressions of GRK-2 and β-arrestin-2 were significantly elevated in cirrhotic patients and rats compared with those of the controls. The interaction of the α 1 adrenergic receptor and β-arrestin-2 was significantly aggravated. This interaction was significantly reversed by GRK-2 inhibitor. Both the protein expression and activity of ROCK-1 were significantly decreased in the mesenteric artery in patients with cirrhosis compared with those of the controls, and this phenomenon was not shown in the cirrhotic rats. Norepinephrine significantly increased the activity of ROCK-1 in normal rats but not in cirrhotic ones. Norepinephrine significantly increased ROCK-1 activity in cirrhotic rats when GRK-2 inhibitor was used. CONCLUSIONS: β-arrestin-2 expression and its interaction with GPCRs are significantly upregulated in the mesenteric arteries in patients and rats with cirrhosis. These upregulations result in GPCR desensitization, G-protein dysfunction and ROCK inhibition. These may explain the decreased contractility of the mesenteric artery in response to vasoconstrictors.

Increasing access to kidney transplantation for sensitized recipient through three-way kidney paired donation with desensitization: The first Indian report

The combination of kidney paired donation(KPD) with desensitization represents a promising method of increasing the rate of living donor kidney transplantation(LDKT) in immunologically challenging patients. Patients who are difficult to match and desensitize due to strong donor specific antibody are may be transplanted by a combination of desensitization and KPD protocol with more immunologically favorable donor. We present our experience of combination of desensitization protocol with three-way KPD which contributed to successful LDKT in highly sensitized end stage renal disease patient. All recipients were discharged with normal and stable allograft function at 24 mo follow up. We believe that this is first report from India where three-way KPD exchange was performed with the combination of KPD and desensitization. The combination of desensitization protocol with KPD improves access and outcomes of LDKT.

Mechanism of charged interface of stargazin EX1 on AMPAR opening and desensitization

OBJECTIVE AMPA-subtype iono⁃tropic glutamate receptors(iGluRs)mediate fast excitatory synaptic transmission in the mammali⁃an central nervous system(CNS).It plays the key role in many central nerves disorder such as epilepsy,depression and schizophrenia.Star⁃gazin(STZ,also named TARP-γ2),as the first TARPs found in CNS,potentiates AMPAR activity by attenuating deactivation and desensitization,enhancing recovery from desensitization,and facilitating agonist affinity and efficacy.However,it is still not fully understanding howγ-2 modu⁃late AMPAR gating.METHODS AND RESULTS The desensitization for different mutation of AMPAR andγ-2 was compared.It was shown that the electric attraction was involved in the interaction of AMPAR andγ-2.In addition,the interaction of KGK motif in ligand binding domain and pre-M1 chain of AMPAR and EX1 ofγ-2 modulate AMPAR opening and desensitization.Substitution of these charged residues had sur⁃prisingly effects on AMPAR desensitization kinet⁃ics.CONCLUSION The electric attraction has two impacts on the channels gating process the first destablizing the receptor closed state and enabling the channel opening,the second pro⁃moting the channels entering desensitization state upon the channel opening.

Effect of desensitization treatment for highly sensitized uremic patients before kidney transplantation

Objective To explore the feasibility and efficacy of desensitization protocol for highly sensitized renal transplant patients ( HSP ) . Methods Thirty - five HSPs ( HLA class - I panel reactive antibody 2〉50 % ) , including 27 patients with a positive T and/or B cell cy-

Successful interferon desensitization in a patient with chronic hepatitis C infection

Treatment of hepatitis C, even when absolutely necessary, is almost impossible when interferon cannot be administered for any reason. We report a 65-year-old patient with chronic hepatitis C virus (HCV) infection and fibrosis, who was unable to receive interferon because of systemic hypersensitivity. The patient was desensitized successfully through gradual incremental exposure to interferon, and HCV infection was eradicated after a complete course of treatment, with no further allergic reactions. This case report that describes successful eradication of hepatitis C in a patient with advanced liver disease after desensitization to interferon revealed that desensitization may not necessarily damage the therapeutic efficacy of the drug.

基于审美分析的口腔美容修复分类诊疗方案(一):基本概念、决策树及临床路径

当前美容修复临床方案多基于欧美国家提出的口腔美感指标(简称欧美审美)制定,但机械地照搬欧美口腔美容修复方案,忽视了其与中国人口腔美感指标(简称中式审美)的差别,是无法有效支撑国人个性化口腔美容修复诊治的。另外,近年发展迅猛的美容修复新技术、新方案层出不穷,但不少热门概念的内涵混淆不清,也缺乏应有的分级诊疗规范,急需讨论明晰。本文从服务好口腔美容修复临床运用出发,探讨了中译词“美学”的不足与误用,美学与美容的区别与联系,美容修复与固定修复的相关关系,还讨论了前牙区、美学区与暴露区的差别、口腔审美分析的诊疗价值,以及脱敏、暗示等疗法在口腔疑难美容修复病例中的运用方法。进一步介绍了审美分析引导的暴露区牙位修复重建的决策树及临床路径,并案析介绍了审美分析评估临床流程、口腔美容修复临床三分类及相应的临床分类诊疗要点。

Progress on the application of graphene-based composites toward energetic materials:A review

Carbon material is an important additive in energetic materials.Graphene is a monolayer carbon material in which carbon atoms are arranged in two-dimensional honeycomb structure,who has special optical,electrical,and mechanical properties.Recently,the application of graphene-based composites in energetic materials has received extensive attention.This review mainly summarizes the applications of graphene and graphene-based nanomaterials in energetic materials.The effects of these materials on the thermal stability,sensitivity,mechanical property,ignition and combustion of energetic materials were discussed.Furthermore,the progress of functionalized modification of graphene has been summarized,including covalent bonding modification and doping modification.These studies show that graphenebased materials exhibit excellent performances and might emerge as promising candidate for energetic materials.

利妥昔单抗快速脱敏治疗 病例报告/病例系列的系统评价

目的系统评价利妥昔单抗快速脱敏治疗的有效性和安全性。方法检索PubMed、Embase、Cochrane、Web of Science、Scopus、中国知识基础设施工程网(CNKI)、万方数据库数字化期刊和重庆维普中文科技期刊数据库,检索时限均为建库至2023年2月。由2位评价员独立筛选文献、提取数据,并评价纳入文献的质量,对结果数据进行描述性分析或统计性分析。系统评价方案已在PROSPERO注册(CRD:42022306557)。结果纳入25项研究(11个病例报告和14个病例系列),共计138例患者进行脱敏治疗,129例脱敏成功(即至少完成一次目标剂量给药)。脱敏前预处理方案为H1、H2受体拮抗剂,糖皮质激素,镇静剂,NSAIDs和对乙酰氨基酚等药物中2种或以上联合,88%的研究预处理分别包含H1受体拮抗剂或糖皮质激素。16项(64.0%)研究报告患者脱敏前皮试情况,皮肤点刺试验(n=16)和皮内试验(n=59)阳性率分别为12.50%、49.15%。17项研究(68.0%)采用3袋-12步法快速脱敏方案,其余为4袋-16步或2袋-8步等多种方法;利妥昔单抗初始给药浓度(即第一袋脱敏药液浓度)为1/10 X-1/10000 X,第一步输注速率基本为1.5~5 mL·min^(-1),单次脱敏总时长4~10.5 h。23项(92%)研究报告患者脱敏过程中变态反应发生情况,其中5项研究未发生变态反应、18项研究中大部分患者在给予对症处理或修改脱敏方案后完成脱敏治疗。结论当前证据表明,利妥昔单抗快速脱敏治疗具有一定的有效性和安全性,但目前缺乏具体的操作性强的高质量证据或执行标准,有待更多大样本、多中心的研究在脱敏前皮试、预处理、个体化脱敏步骤和脱敏过程中过敏反应处理等方面进一步探索。

生物活性材料治疗修复中常见的牙本质敏感症的效果研究

目的:牙本质敏感症(dentin hypersensitivity,DH)作为口腔中常见的一种症状和疾病,可能对患者的生活质量产生较大影响,本研究通过体外实验比较Regesi生物活性材料、Gluma脱敏剂和可乐丽菲露Clearfil SE Bond两步法粘接剂对牙本质小管封闭程度及耐久性的差异,为其用于牙本质敏感症的治疗提供数据支持。方法:体外实验中,用离体牙制作牙本质敏感模型,根据脱敏材料的不同进行随机分组(对照组:人工唾液组;A组:Regesi组;B组:Gluma组;C组:Clearfil SEBond组),通过SEM观察脱敏剂作用后,4组牙本质敏感模型的形貌及牙本质小管封闭效果,分析对比其脱敏效果的差异,并通过耐磨性实验,分析材料间脱敏效果持久性之间的差异及表面硬度的差异。结果:SEM观察可见A、B、C组的牙本质小管封闭效果均优于对照组,结果有统计学差异,其中A组封闭效果最好,较其他两组有统计学差异。耐磨性实验前后,A组的表面硬度均高于其他三组,结果有统计学差异。结论:Regesi生物活性材料较Gluma脱敏剂和Clearfil SE Bond两步法粘接剂对牙本质小管的封闭程度及耐久性能更佳,能更好地治疗牙本质敏感症。

祛风脱敏通窍法治疗小儿过敏性鼻炎的经验介绍

过敏性鼻炎是儿科临床常见病、多发病,近年来发病率呈逐年升高趋势。本文旨在介绍万力生教授辨治小儿过敏性鼻炎的经验,为临床小儿过敏性鼻炎的诊治开拓思路。万力生教授认为“体禀特异,外风引动”为其核心病机,运用祛风脱敏通窍治法,创立验方“祛风脱敏通窍汤”,分期辨治小儿过敏性鼻炎。并附验案1例,以飨同道。

Nd:YAG激光和Er:YAG激光治疗牙本质敏感的临床对比研究

目的探讨Nd:YAG激光和Er:YAG激光治疗牙本质敏感(Dentin Hypersensitivity,DH)的效果。方法收治佛山市第一人民医院2021年3月至2022年12月期间就诊的牙本质敏感93例患者共259颗牙,患者均在受到冷、酸、甜及刷牙等刺激后存在酸痛感,诊断为DH。随机分为3组,分别给予常规脱敏剂治疗组(31例患者,86颗患牙)、Nd:YAG激光治疗组(31例患者,90颗患牙)、Er:YAG激光治疗组(31例患者,83颗患牙)3种方法,其中激光组尝试改变激光照射参数及时间,寻求最好的治疗参数。对比3种脱敏方法的即刻效果、1周效果、1个月效果及3个月效果。结果治疗前3组对冷空气及机械刺激反应的VAS评分无明显差异(P>0.05);治疗后各个时间段Nd:YAG激光组和Er:YAG激光组对冷空气刺激反应均明显轻于对照组(P<0.05)。治疗后各个时间段Nd:YAG激光组和Er:YAG激光组对机械刺激反应均明显轻于对照组(P<0.05)。3组经治疗后均获得一定疗效,Nd:YAG激光组和Er:YAG激光组的效果好于常规组,但差异无统计学意义(P>0.05)。结论Nd:YAG激光、Er:YAG激光治疗DH与常规脱敏方法相比,明显降低患者的冷空气和机械刺激反应,在一定程度上提升了治疗效果。

基于上下文编码器网络的油气曲线图像脱敏方法研究

数据对于石油企业就是资产。数据加密与数据脱敏都是针对数据安全的策略,但目前数据脱敏技术仅能够针对文本实现,缺少石油企业中大量保有的图像数据脱敏技术。针对目前脱敏技术存在的不足之处及油气田勘探中的曲线图像数据特点,借鉴深度学习图像修复方法,提出一套基于上下文编码器的脱敏技术,弥补了行业内对于图像数据无法脱敏的缺陷。对该方法进行详细的测试后取得了较好的脱敏效果。对比传统方法,结果证明其能够在曲线图像这种具有专业特殊性的数据中取得更明显的效果以及更可靠的脱敏效果。

高校数据治理安全研究综述与展望

高校大数据治理系统的安全性,一直以来都是各界高度关注的问题。首先,介绍了数据治理系统安全技术在高校中的研究历程;而后,总结了现存的安全问题与挑战;其次,对于列出的安全问题从人员监管和技术实现两个方面提出解决方案。在技术方面,分别列举了数据分级、数据脱敏、数据权限管理信息系统等五种安全技术及措施;最后对高校数据治理安全领域的发展进行展望。