铜增韧Mo_(2)BC陶瓷的力学性能和摩擦学性能

采用快速热压反应烧结法制备高强韧Mo_(2)BC/Cu陶瓷基复合材料。研究铜含量对Mo_(2)BC/Cu复合材料的微观组织、力学性能和摩擦学性能的影响,并对其增韧机制和磨损机理进行分析。研究结果表明:Cu均匀地分散在Mo_(2)BC基体中,具有细化晶粒的作用。Mo_(2)BC/Cu复合材料中铜可以添加的最大质量分数为7.5%。随着铜含量的增加,Mo_(2)BC/Cu复合材料的弯曲强度和断裂韧性增加。当Cu质量分数为7.5%时,复合材料的弯曲强度和断裂韧性最高,分别为625.1 MPa和7.4 MPa·m^(1/2),与Mo_(2)BC陶瓷相比,分别提高了24%和62%,其主要的增韧机制为铜的塑性变形、晶粒拔出、桥接效应和裂纹的偏转。此外,铜的添加还可以明显提高Mo_(2)BC/Cu复合材料的摩擦磨损性能。当Cu质量分数为2.5%时,复合材料的摩擦因数可低至0.36,磨损量最小,耐磨性最优,其主要的磨损机制为轻微的二体磨粒磨损和氧化磨损。

基于新载体的BC-L-83碳三加氢催化剂的开发及工业应用

针对国产碳三液相加氢BC-L-83催化剂的特点和不足,开发了基于新载体的BC-L-83碳三液相选择加氢催化剂,考察了新BC-L-83催化剂在工业乙烯装置上的长周期应用情况。工业应用结果表明,新BC-L-83催化剂在国内1.2 Mt/a乙烯装置中首次稳定运行22个月以上,催化剂活性高,抗波动性能好,丙烯平均选择性超过73%,更好地满足了工业乙烯装置脱除碳三馏分中的丙炔、丙二烯和增产丙烯的要求,具有明显的技术和成本优势。

BC120全自动血培养系统作为药品无菌检查替代方法的可行性研究

目的:评价基于呼吸信号检测原理的BC120全自动血培养系统在特定注射剂产品中作为替代方法开展无菌检查的可行性。方法:收集2种不同类型的无菌制剂,考察在专属性、检测限和方法适用性等方面与中国药典无菌检查法是否存在差异。结果:在严格按照BC120全自动血培养系统使用说明操作的前提下,该系统在专属性和检测限参数上与药典方法无显著差异,多数情况下比药典方法更快地报告阳性结果。结论:BC120全自动血培养系统在风险管理的前提下,经过验证,可作为药典无菌检查的替代方法用于特定注射剂产品的生产过程控制和快速放行。Objective: To evaluate the feasibility of BC120 blood culture system as an alternative method for sterility test. Methods: Two aseptic preparations were collected, to examine the differences between them and pharmacopoeia method in specificity, detection limit and method applicability. Results: According to the instructions of BC120 blood culture system, there is no significant difference between the system and the pharmacopoeia method in specificity and detection limit parameters, and in most cases, the positive results are reported faster than the pharmacopoeia method. Conclusions: Under the premise of risk management, BC120 blood culture system can be used as an alternative method for sterile testing in the production process of specific injection products for sterile quality control and rapid release after validation.

miR-21低表达对垂体瘤细胞系RC-4BC增殖、凋亡的影响及与PTEN靶向关系

目的观察微小RNA-21(miR-21)低表达对垂体瘤细胞系RC-4BC增殖、凋亡的影响,并分析其与第10号染色体丢失的张力蛋白同源磷酸酶基因(PTEN)的靶向关系。方法取对数生长期的RC-4BC细胞分为两组,沉默组转染miR-21抑制物miR-21 inhibitor,阴性对照组转染抑制物阴性对照NC-inhibitor,采用RT-PCR法检测miR-21、第10号染色体丢失的张力蛋白同源磷酸酶基因(PTEN)mRNA,采用CCK8实验观察两组细胞增殖能力(以OD值表示),采用平板克隆实验观察两组细胞集落形成能力(以集落形成数表示),采用流式细胞术观察两组细胞凋亡率并观察细胞周期分布情况。收集RC-4BC细胞制备单细胞悬液,分别将miR-21 mimics或NC-mimics与PTEN-WT或PTEN-MUT共转染至RC-4BC细胞,转染后细胞标记为miR-21 mimics+PTEN-WT组、NC-mimics+PTEN-WT组、miR-21 mimics+PTEN-MUT组、NC-mimics+PTEN-MUT组,采用双荧光素酶报告基因实验验证miR-21与PTEN的靶向关系。结果沉默组RC-4BC细胞中miR-21、PTEN mRNA相对表达量分别为0.30±0.08、2.89±0.14,阴性对照组RC-4BC细胞中miR-21、PTEN mRNA相对表达量分别为1.01±0.02、0.99±0.03,两组相比,P均<0.05。沉默组RC-4BC细胞24 h、48 h、72 h时OD值均低于阴性对照组(P均<0.05)。沉默组RC-4BC细胞集落形成数低于阴性对照组(P<0.05)。沉默组RC-4BC细胞凋亡率高于阴性对照组(P<0.05)。沉默组RC-4BC细胞G0/G1期占比65.65%±7.82%、S期占比19.25%±3.70%,阴性对照组RC-4BC细胞G0/G1期占比45.62%±5.03%、S期占比35.72%±4.67%,两组相比,P均<0.05。miR-21 mimics+PTEN-WT组、NC-mimics+PTEN-WT组、miR-21 mimics+PTEN-MUT组、NC-mimics+PTEN-MUT组细胞的相对荧光素酶活性分别为0.39±0.07、1.02±0.03、1.01±0.04、1.00±0.03,其中miR-21 mimics+PTEN-WT组相对荧光素酶活性与其他各组相比,P均<0.05。结论沉默miR-21能够移至垂体瘤细胞系RC-4BC的增殖、促进其凋亡,其机制可能与靶向调控PTEN基因有关。

高压管汇中活动弯管BC直接头失效分析

高压管汇作为压裂设备核心部件之一,比泵头体、泵阀等易损件失效危害更大。为此,以失效活动弯管BC直接头为研究对象,采用硬度检测、金相检验、扫描电镜检测等手段分析了失效直接头材料力学性能和断口形貌,并利用有限元方法计算了直接头轴肩根部含初始缺陷处的应力强度。分析结果表明:BC直接头失效是由应力集中导致的脆性断裂而产生;应力集中、组装配合不当使其受力不均、材料硬度偏高和力学性能不达标,由此造成接头在循环载荷作用下发生脆性断裂;建议严格控制接头原材料复检及产品质量检验,规范产品结构组装标准,定量规范管汇安装标准。所得结论可为压裂高压管汇接头的失效分析提供理论参考。

Genesis of LCT Pegmatites during Early Paleozoic Orogeny of the North Qinling Orogenic Belt,China:Emplacement Conditions and Structural Control

The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we investigated it combining pegmatite orientation measurement with oxygen isotope geothermometry and fluid inclusion study.The orientations of type A1 pegmatites(P_(f)<σ_(2))are predominantly influenced by P-and T-fractures due to simple shearing in Shiziping dextral thrust shear zone during D_(2)deformation,whereas type A2 pegmatites(contemporaneous with D_(4))are governed by hydraulic fractures aligned with S_(0)and S_(0+1)stemming from fluid pressure(P_(f)<σ_(2)).Additionally,type B pegmatites(P_(f)≤σ_(2))exhibit orientations shaped by en echelon extensional fractures in local ductile shear zones(contemporaneous with D_(3)).The albite-quartz oxygen isotope geothermometry and microthermometric analysis of fluid inclusions in elbaites from the latest pegmatites(including types B and A2)suggest that the crystallization P-T for late magmatic and hydrothermal stages are 527.5-559.2℃,320℃,3.1-3.6 kbar and 2.0 kbar,respectively.Our observations along with previous studies suggest that the genesis of the LCT pegmatites was a long-term,multi-stage event during early Paleozoic orogeny(including the collision stage)of the NQB,and was facilitated by various local fractures.

Ambient-Condition Strategy for Production of Hollow Ga_(2)O_(3)@rGO Crystalline Nanostructures Toward Efficient Lithium Storage

Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and rGO.The as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower capacity.Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of electrodes.Additionally,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage behaviors.This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications.

一种Deoxys-BC算法的中间相遇攻击方法

Deoxys-BC密码算法是在2014年亚密会上发布的一种轻量级可调分组密码算法,该算法的设计采用SPN结构和TWEAK框架。通过研究Deoxys-BC密码算法的内部特征与密钥扩展的特点,利用控制调柄差分的方法,并结合差分枚举技术和轮密钥调柄差分叠加消除特性,构造6轮Deoxys-BC-256和7轮Deoxys-BC-384的中间相遇区分器。利用此区分器,通过减少猜测的字节量,来达到降低复杂度的效果,改进了9轮Deoxys-BC-256和11轮Deoxys-BC-384中间相遇攻击的结果。相比Deoxys-BC系列密码算法现有的中间相遇攻击结果,该攻击的时间复杂度和存储复杂度均大幅下降。

Autologous hematopoietic stem cell transplantation conditioning regimens and chimeric antigen receptor T cell therapy in various diseases

Conditioning regimens employed in autologous stem cell transplantation have been proven useful in various hematological disorders and underlying malignancies;however,despite being efficacious in various instances,negative consequences have also been recorded.Multiple conditioning regimens were extracted from various literature searches from databases like PubMed,Google scholar,EMBASE,and Cochrane.Conditioning regimens for each disease were compared by using various end points such as overall survival(OS),progression free survival(PFS),and leukemia free survival(LFS).Variables were presented on graphs and analyzed to conclude a more efficacious conditioning regimen.In multiple myeloma,the most effective regimen was high dose melphalan(MEL)given at a dose of 200/mg/m2.The comparative results of acute myeloid leukemia were presented and the regimens that proved to be at an admirable position were busulfan(BU)+MEL regarding OS and BU+VP16 regarding LFS.In case of acute lymphoblastic leukemia(ALL),BU,fludarabine,and etoposide(BuFluVP)conferred good disease control not only with a paramount improvement in survival rate but also low risk of recurrence.However,for ALL,chimeric antigen receptor(CAR)T cell therapy was preferred in the context of better OS and LFS.With respect to Hodgkin’s lymphoma,mitoxantrone(MITO)/MEL overtook carmustine,VP16,cytarabine,and MEL in view of PFS and vice versa regarding OS.Non-Hodgkin’s lymphoma patients were administered MITO(60 mg/m2)and MEL(180 mg/m2)which showed promising results.Lastly,amyloidosis was considered,and the regimen that proved to be competent was MEL 200(200 mg/m2).This review article demonstrates a comparison between various conditioning regimens employed in different diseases.

Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

BC/CS复合水凝胶的3D打印工艺研究

以细菌纤维素(BC)和壳聚糖(CS)为基质的水凝胶同时具有细菌纤维素的高生物相容性和壳聚糖的抗菌性能,在伤口敷料、组织工程等领域获得了广泛的应用,但其3D打印仍面临困难。本文利用BC和CS的物理特性和其交联机制,制备出可用于3D打印的BC/CS复合水凝胶油墨,同时使用纳米粘土作为流变改性剂,提升水凝胶的自支撑能力。对于交联方法,不再采用传统的浸泡方式,使用喷雾器将戊二醛溶液均匀喷洒在打印样品表面,既不会破坏样品的结构,也可以达到交联的目的。接着,构建了一种适合BC/CS复合水凝胶打印的3D打印系统,并在此基础上研究分析了喷头挤出压力、移动速度、打印高度对水凝胶精度的影响。本文提出的方法有望实现BC/CS复合水凝胶的墨水直写(DIW)打印提供指导。

TMC BC ROBO 6智能采血系统故障维修3例

简要介绍了TMC BC ROBO 6智能采血系统的工作原理,分析了该设备在日常使用中出现的3例故障的原因,并给出了故障排除方法,为临床工程师排除类似故障提供了参考。

迈瑞BC-7500全自动血细胞分析仪的性能验证

目的:对迈瑞BC-7500全自动血细胞分析仪进行性能评价,确保仪器检测数据的准确性。方法:参照WS/T406-2012《临床血液学检验常规项目的分析质量要求》等行标要求,进行迈瑞BC-7500全自动血细胞分析仪本底计数、携带污染率、批内精密度、日间精密度、线性范围、正确度、参考范围、不同吸样模式的结果可比性、实验室内部的可比性、仪器间五分类比对、人机五分类比对的验证分析。结果:迈瑞BC-7500全自动血细胞分析仪本底计数、携带污染率、精密度、线性范围、正确度、参考范围、不同吸样模式的结果可比性、实验室内部的可比性、仪器间五分类比对、人机五分类比对验证均符合行标要求。结论:本实验室使用的迈瑞BC-7500全自动血细胞分析仪经验证其性能符合行标要求,检测结果准确可靠,可满足临床需求。

Autophagy and mitophagy as potential therapeutic targets in diabetic heart condition:Harnessing the power of nanotheranostics

Autophagy and mitophagy pose unresolved challenges in understanding the pathology of diabetic heart condition(DHC),which encompasses a complex range of cardiovascular issues linked to diabetes and associated cardiomyopathies.Despite significant progress in reducing mortality rates from cardiovascular diseases(CVDs),heart failure remains a major cause of increased morbidity among diabetic patients.These cellular processes are essential for maintaining cellular balance and removing damaged or dysfunctional components,and their involvement in the development of diabetic heart disease makes them attractive targets for diagnosis and treatment.While a variety of conventional diagnostic and therapeutic strategies are available,DHC continues to present a significant challenge.Point-of-care diagnostics,supported by nanobiosensing techniques,offer a promising alternative for these complex scenarios.Although conventional medications have been widely used in DHC patients,they raise several concerns regarding various physiological aspects.Modern medicine places great emphasis on the application of nanotechnology to target autophagy and mitophagy in DHC,offering a promising approach to deliver drugs beyond the limitations of traditional therapies.This article aims to explore the potential connections between autophagy,mitophagy and DHC,while also discussing the promise of nanotechnology-based theranostic interventions that specifically target these molecular pathways.

Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation

A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results.

Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management

Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian-level wind velocity and thermal condition.In this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the complex.Compared to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside buildings.Effects of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are assessed.The results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the buildings.Furthermore,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building.

Design and high-power testing of offline conditioning cavity for CiADS RFQ high-power coupler

To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity features two coupling ports and two tuners,operating at a frequency of 162.5 MHz with a tuning range of 3.2 MHz.Adjusting the installation angle of the coupling ring and the insertion depth of the tuner helps minimize cavity losses.We performed electromagnetic structural and multiphysics simulations,revealing a minimal theoretical power loss of 4.3%.However,when the cavity frequency varied by110 kHz,theoretical power losses increased to10%,necessitating constant tuner adjustments during conditioning.Multiphysics simulations indicated that increased cavity temperature did not affect frequency variation.Upon completion of the offline high-power conditioning platform,we measured the transmission performance,revealing a power loss of 6.3%,exceeding the theoretical calculation.Conditioning utilized efficient automatic range scanning and standing wave resonant methods.To fully condition the power coupler,a 15°phase difference between two standing wave points in the condition-ing system was necessary.Notably,the maximum continuous wave power surpassed 20 kW,exceeding the expected target.

Enhancing Erectile Function and Alleviating Andropause Symptoms: Clinical Efficacy of a Human Stem Cell Conditioned Medium Cream

Erectile dysfunction (ED) is increasingly prevalent in Japan, exceeding 30%, and increasing with age. Unhealthy lifestyle habits, obesity, insufficient exercise, and smoking have been implicated in its pathogenesis, along with endothelial dysfunction of the corpora cavernosa and impaired blood flow to the penis considered underlying factors. However, the current treatments are limited to Phosphodiesterase-5 (PDE5) inhibitors. ED is the primary symptom of andropathy. This study reports the clinical efficacy of human stem cell-conditioned medium cream for ED treatment. Ten men without underlying diseases suspected of andropause with ED (mean age 43.2 ± 4.4 y, Hb 15.2 ± 0.6 gm/dL, AST/ALT 30.2/37.9 ± 12.4/14.0, eGFR 82.7 ± 12.4 mL/min/1.73 m2) were targeted. The cream was applied twice daily to the genital and scrotal areas. The erectile hardness score (EHS), International Index of Erectile Function-5 (IIEF-5), and Aging Male Symptoms (AMS) scale were used to evaluate the participants before and 30 days after use, and the results were compared using paired t-tests. The post-use qualitative opinions were collected through interviews. Significant improvements were observed compared to baseline in the IIEF-5 (11.8 ± 4.6→17.2 ± 5.1, P < 0.001), and AMS (46.3 ± 6.7→37.6 ± 5.3, P < 0.001) scores post cream use. EHS did not show a statistically significant difference, but a trend towards improvement was observed. Qualitative feedback included increased morning erection, improved maintenance of erection during intercourse, and reduced post work fatigue. Human stem cell-conditioned medium contains endothelial growth factors that potentially contribute to the improvement of ED and andropause by enhancing corporal endothelial function. Future studies should include control groups to further investigate the efficacy of these treatments.

Multi-soliton solutions of coupled Lakshmanan-Porsezian-Daniel equations with variable coefficients under nonzero boundary conditions

This paper aims to investigate the multi-soliton solutions of the coupled Lakshmanan–Porsezian–Daniel equations with variable coefficients under nonzero boundary conditions.These equations are utilized to model the phenomenon of nonlinear waves propagating simultaneously in non-uniform optical fibers.By analyzing the Lax pair and the Riemann–Hilbert problem,we aim to provide a comprehensive understanding of the dynamics and interactions of solitons of this system.Furthermore,we study the impacts of group velocity dispersion or the fourth-order dispersion on soliton behaviors.Through appropriate parameter selections,we observe various nonlinear phenomena,including the disappearance of solitons after interaction and their transformation into breather-like solitons,as well as the propagation of breathers with variable periodicity and interactions between solitons with variable periodicities.

Evaluation of Mechanical Properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions

This study investigated the mechanical properties of beech(Fagus sylvatica L.)and fir(Abies alba)wood from Bosnia and Herzegovina under outdoor exposure.Samples were exposed for 3-month exposure to assess bending strength,color changes,and surface quality.Results showed outdoor exposure negatively affected mechanical properties,particularly in samples with extended finger joints,causing significant surface cracks in uncoated samples.Beech wood exhibited notable color changes under exposure,with approximately 50%darkening without coating compared to 25%under covered conditions.Coated samples displayed minimal color changes,affirming the efficacy of surface treatment.Fir wood exhibited a roughness of 8.264μm,while beechwood average roughness increased from 6.767 to 13.916μm after exposure,with micro-pore development affecting water performance.Microscopic analysis identified prevalent fungal colonies,including Penicillium,Aureobasidium,Sclerophoma,and Chaetomium,underscoring their role in organic matter decomposition.This study highlights the importance of wood exposure and treatment selection for various applications.