Usefulness of an Anisotropic Diffusion Method in Cerebral CT Perfusion Study Using Multi-Detector Row CT

Purpose: To present an application of the anisotropic diffusion (AD) method to improve the accuracy of the functional images of perfusion parameters such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) generated from cerebral CT perfusion studies using multi-detector row CT (MDCT). Materials and Methods: Continuous scans (1 sec/rotation ×60 sec) consisting of four 5-mm-thick contiguous slices were acquired after an intravenous injection of iodinated contrast material in 6 patients with cerebrovascular disease using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. New image data were generated by thinning out the above original images at an interval of 2 sec or 3 sec. The thinned-out images were then interpolated by linear interpolation to generate the same number of images as originally acquired. The CBF, CBV and MTT images were generated using deconvolution analysis based on singular value decomposition. Results: When using the AD method, the correlation coefficient between the MTT values obtained from the original and thinned-out images was significantly improved. Furthermore, the coefficients of variation of the CBF, CBV and MTT values in the white matter significantly decreased as compared to not using the AD method. Conclusion: Our results suggest that the AD method is useful for improving the accuracy of the functional images of perfusion parameters and for reducing radiation exposure in cerebral CT perfusion studies using MDCT.

A harmonic-wave bio-thermal method for continuous monitoring skin thermal conductivity and capillary perfusion rate

The revelation of thermal energy exchange mechanism of human body is challenging yet worthwhile,because it can clearly explain the changes in human symptoms and health status.Understanding,the heat transfer of the skin is significant because the skin is the foremost organ for the energy exchange between the human body and the environment.In order to diagnose the physiological conditions of human skin without causing any damage,it is necessary to use a non-invasive measurement technique by means of a conformal flexible sensor.The harmonic method can minimize the thermal-induced injury to the skin due to its low heat generating properties.A novel type of computational theory assessing skin thermal conductivity,blood perfusion rate of capillaries in the dermis,and superficial subcutaneous tissues was formed by combining the multi-medium thermal diffusion model and the bio-thermal model(Pennes equation).The skins of the hand back of six healthy subjects were measured.It was found that the results revealed no consistent changes in thermal conductivity were observed across genders and ages.The measured blood perfusion rates were within the range of human capillary flow.It was found that female subjects had a higher perfusion rate range(0.0058-0.0061 s^(-1))than male subjects(0.0032-0.0049 s^(-1)),which is consistent with invasive medical studies about the gender difference in blood flow rates and stimulated effects in relaxation situations.

Temperature-dependent photoluminescence on organic inorganic metal halide perovskite CH3NH3Pb I3-xClx prepared on ZnO/FTO substrates using a two-step method

Temperature-dependent photoluminescence characteristics of organic-inorganic halide perovskite CH3NH3Pb I3-xClx films prepared using a two-step method on ZnO/FTO substrates were investigated. Surface morphology and absorption characteristics of the films were also studied. Scanning electron microscopy revealed large crystals and substrate coverage. The orthorhombic-to-tetragonal phase transition temperature was-140 K. The films＇ exciton binding energy was 77.6 ± 10.9 meV and the energy of optical phonons was 38.8 ± 2.5 meV. These results suggest that perovskite CH3NH3Pb I（3-x）Clx films have excellent optoelectronic characteristics which further suggests their potential usage in perovskitebased optoelectronic devices.

Applying the Dynamic Two-Step Method to Forecast Remaining Oil Distribution of Lower Series ,Xiaermen Oilfield

The distribution of remaining oil is often described qualitatively. The remaining oil distributed in the whole reservoir is calculated according to the characteristics of the space distribution of the saturation of remaining oil. Logging data are required to accomplish this. However, many such projects cannot be completed. Since the old study of remaining oil distribution could not be quantified efficiently, the ＂dynamic two-step method＂ is presented. Firstly, the water cut of every flow unit in one well at one time is calculated according to the comprehensive water cut of a single well at one time. Secondly, the remaining oil saturation of the flow unit of the well at one time is calculated based on the water cut of the flow unit at a given time. The results show that ＂dynamic two-step method＂ has characteristics of simplicity and convenience, and is especially suitable for the study of remaining oil distribution at high water-cut stage. The distribution of remaining oil presented banding and potato form, remaining oil was relatively concentrated in faultage neighborhood and imperfect well netting position, and the net thickness of the place was great. This proposal can provide an effective way to forecast remaining oil distribution and enhance oil recovery, especially applied at the high water-cut stage.

Extended Generalized Riccati Equation Mapping for Thermal Traveling-Wave Distribution in Biological Tissues through a Bio-Heat Transfer Model with Linear/Quadratic Temperature-Dependent Blood Perfusion

Analytical thermal traveling-wave distribution in biological tissues through a bio-heat transfer (BHT) model with linear/quadratic temperature-dependent blood perfusion is discussed in this paper. Using the extended generalized Riccati equation mapping method, we find analytical traveling wave solutions of the considered BHT equation. All the travelling wave solutions obtained have been used to explicitly investigate the effect of linear and quadratic coefficients of temperature dependence on temperature distribution in tissues. We found that the parameter of the nonlinear superposition formula for Riccati can be used to control the temperature of living tissues. Our results prove that the extended generalized Riccati equation mapping method is a powerful tool for investigating thermal traveling-wave distribution in biological tissues.

A Mathematical Model to Solve Bio-Heat Transfer Problems through a Bio-Heat Transfer Equation with Quadratic Temperature-Dependent Blood Perfusion under a Constant Spatial Heating on Skin Surface

We consider the one-dimensional bio-heat transfer equation with quadratic temperature-dependent blood perfusion, which governs the temperature distribution inside biological tissues. Using an extended mapping method with symbolic computation, we obtain the exact analytical thermal traveling wave solution, which describes the non-uniform temperature distribution inside the bodies. The found exact solution is used to investigate the temperature distribution in the tissues. It is found that the surrounding medium with higher temperature does not necessarily imply that the tissue will quickly (after a short duration of heating process) reach the desired temperature. It is also found that increased perfusion causes a decline in local temperature.

The convergence ball and error analysis of the two-step Secant method

Under the assumption that the nonlinear operator has Lipschitz continuous divided differences for the first order,we obtain an estimate of the radius of the convergence ball for the two-step secant method.Moreover,we also provide an error estimate that matches the convergence order of the two-step secant method.At last,we give an application of the proposed theorem.

The preparation of Garcinia Glycosides solid dispersion and intestinal absorption by rat in situ single pass intestinal perfusion

Garcinia Glycosides is a candidate drug obtained by structural modification of Gambogic Acid (GA), which was acquired through High Throughput Screening(HTS). As Garcinia Glycosides is an effective but insoluble anti-tumor drug, the aim of this study was to obtain a solid dispersion form Garcinia Glycosides by using solvent-melt method so that improve the solubility and dissolution rate. The solid dispersion was characterized by High Performance Liquid Chromatography (HPLC), infrared spectroscopy and evaluated the intestinal absorption of the drug by rat in situ single pass intestinal perfusion. The results showed the increase of solubility, dissolution velocity and absorption compared to other forms. This indicated that solid dispersion could greatly improve the relative bioavailability of Garcinia Glycosides in vivo.

Solution of Nonlinear Integro Differential Equations by Two-Step Adomian Decomposition Method (TSAM)

The Adomian decomposition method (ADM) can be used to solve a wide range of problems and usually gets the solution in a series form. In this paper, we propose two-step Adomian Decomposition Method (TSAM) for nonlinear integro-differential equations that will facilitate the calculations. In this modification, compared to the standard Adomian decomposition method, the size of calculations was reduced. This modification also avoids computing Adomian polynomials. Numerical results are given to show the efficiency and performance of this method.

健康促进图示法对门诊膀胱肿瘤灌注患者疾病知识掌握程度的影响

目的 探究健康促进图示法对门诊膀胱肿瘤灌注患者疾病知识掌握程度的影响。方法 选取2021年1月至2022年12月于江苏省淮安市第一人民医院门诊输液室接受膀胱灌注治疗的102例膀胱肿瘤患者为研究对象,按照随机数字表法将其分为对照组和观察组,各51例。对照组实施常规护理干预,观察组在对照组基础上实施健康促进图示法干预。比较两组遵医行为、相关知识掌握程度、心理状态,及遵医行为情况。结果 干预后,两组疾病相关知识掌握、遵医行为评分高于干预前,观察组高于对照组;焦虑状态评分低于干预前,观察组低于对照组(P<0.05)。结论 门诊膀胱肿瘤灌注患者实施健康促进图示法干预可有效改善患者遵医行为,有助于焦虑情绪的消除,提高患者对疾病知识的认知程度。

一种小鼠原代肝细胞的分离与培养方法

目的:探索一种高效、稳定的小鼠原代肝细胞分离方法,并延长其体外培养的时间。方法:取成年雄性C57BL/6小鼠,以含双抗的D-Hanks灌流液经肝门静脉充分灌注肝脏,然后以0.2 mg/mL的Ⅳ型胶原酶灌注消化,接着过滤、离心、洗涤,获得小鼠原代肝细胞。通过台盼蓝染色检验小鼠原代肝细胞活率,利用倒置显微镜观察肝细胞的形态变化,糖原染色鉴定细胞纯度,添加ITS-X和HGF细胞因子延长小鼠原代肝细胞的体外培养时间。结果:平均每只成年小鼠肝脏可提取获得原代肝细胞约2×107个,台盼蓝染色显示细胞活率均超过95%,糖原染色结果表明此方法获得的原代肝细胞纯度高于95%,通过添加HGF和ITS-X两种细胞因子能够有效地延长肝细胞形态的体外维持时间。结论:本实验在原有小鼠原代肝细胞两步灌流分离法和培养的基础上,经过优化,成功建立了一种高效、稳定的小鼠原代肝细胞分离和培养方法,为肝脏的体外研究提供了技术保障。

A Novel Method of Fabricating a Well-Faceted Large-Crystal Diamond Through MPCVD

A novel method was developed to deposit a large crystal diamond with good facets up to 1000 μm on a tungsten substrate using a microwave plasma enhanced chemical vapor deposition （MPCVD）. This method consists of two steps, namely single-crystal nucleation and growth. Prior to the fabrication of the well-faceted, large crystal diamond, an investigation was made into the nucleation and growth of the diamond which were affected by the O2 concentration and substrate temperature. Deposited diamond crystals were characterized by scanning electron microscopy and micro-Raman spectroscopy. The results showed that the conditions of single-crystal nucleation were appropriate when the ratio of H2/CH4/O2 was about 200/7.0/2.0, while the sub- strate temperature Ts of 1000℃ to 1050℃ was the appropriate range for single-crystal diamond growth. Under the optimum parameters, a well-faeeted large crystal diamond was obtained.

In-depth understanding of ionic liquid assisted perovskite film formation mechanism for two-step perovskite photovoltaics

Ionic liquids(ILs)have been widely applied in the one-step fabrication of perovskite with noticeable enhancement in the device performance.However,in-depth mechanism of ionic-liquid-assisted perovskite film formation is not well understood for also important two-step perovskite fabrication method,with better control of crystallization behavior.In this work,we introduced ionic liquid methylammonium formate(MAFa)into organic salt to produce perovskite film via a two-step method.Systematic investigations on the influence of MAFa on the perovskite thin film formation mechanism were performed.Ionic liquid is shown to assist lowering the perovskite formation enthalpy upon the density functional theory(DFT)calculation,leading to an accelerated crystallization process evidenced by in-situ UV-Vis absorption measurement.A gradient up-down distribution of ionic liquid has been confirmed by timeof-flight SIMS.Importantly,besides the surface passivation,we found the HCOO-can diffuse into the perovskite crystals to fill up the halide vacancies,resulting in significant reduction of trap states.Uniform perovskite films with significantly larger grains and less defect density were prepared with the help of MAFa IL,and the corresponding device efficiency over 23%was obtained by two-step process with remarkably improved stability.This research work provides an efficient strategy to tune the morphology and opto-electronic properties of perovskite materials via ionic-liquid-assisted two-step fabrication method,which is beneficial for upscaling and application of perovskite photovoltaics.

A class of twostep continuity Runge-Kutta methods for solving singular delay differential equations and its convergence

An idea of relaxing the effect of delay when computing the Runge-Kutta stages in the current step and a class of two-step continuity Runge-Kutta methods （TSCRK） is presented. Their construction, their order conditions and their convergence are studied. The two-step continuity Runge-Kutta methods possess good numerical stability properties and higher stage-order, and keep the explicit process of computing the Runge-Kutta stages. The numerical experiments show that the TSCRK methods are efficient.

A Remarkable Chord Iterative Method for Roots of Uncertain Multiplicity

In this note we at first briefly review iterative methods for effectively approaching a root of an unknown multiplicity. We describe a first order, then a second order estimate for the multiplicity index m of the approached root. Next we present a second order, two-step method for iteratively nearing a root of an unknown multiplicity. Subsequently, we introduce a novel chord, or a two- step method, not requiring beforehand knowledge of the multiplicity index m of the sought root, nor requiring higher order derivatives of the equilibrium function, which is quadratically convergent for any , and then reverts to superlinear.

Explicit solutions to some nonlinear physical models by a two-step ansatz

Explicit solutions are derived for some nonlinear physical model equations by using a delicate way of two-step ansatz method.

基于Morris方法的微波消融肺组织温度场参数敏感度分析

为了获取微波消融肺组织温度场中组织特性敏感度,采用有限元方法建立微波消融肺组织计算模型,进行电磁场-温度场的耦合,基于Morris方法获取组织电导率(σ)、相对介电常数(ε)、导热率(k)、密度(ρ)、比热容(Cp)和血液灌注率(ωb)的敏感度,建立二维有限元模型.肺组织的σ、ε、k、ρ、Cp、ωb六个参数各设置4个水平,分别获取在50 W、300 s时的微波消融肺组织的消融面积和中心温度,并采用Morris方法,分析各参数对消融面积和消融形状的影响程度.结果表明,血液灌注率、相对介电常数、电导率是对微波消融肺组织的消融区域和消融形状影响较大的参数.

马归液联合吉西他滨膀胱灌注治疗膀胱癌的疗效观察

目的观察马归液联合吉西他滨(gemcitabine,GEM)膀胱灌注治疗膀胱癌的疗效。方法将2016年1月至2017年12月在湖南中医药大学第一附属医院泌尿外科行经尿道膀胱肿瘤电切除术(transurethral resection of bladder tumors,TURBT)的90例非肌层浸润性膀胱癌(non-muscular-invasive bladder cancer,NMIBC)患者随机分为治疗1组、治疗2组和对照组,每组30例。对照组采用GEM膀胱灌注治疗;治疗1组以GEM联合马归液膀胱灌注治疗;治疗2组在治疗1组基础上加入马归液口服。检测治疗前后各组患者的CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)、血管内皮生长因子(vascular endothelial growth factor,VEGF)水平;随访各组患者术后1年、2年、3年的复发例数;记录各组患者恶心呕吐、血尿、膀胱刺激征、尿常规异常、发热的不良反应发生例数。结果治疗后,治疗1组、治疗2组CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)较治疗前均升高,血清VEGF水平均降低(P<0.05);与对照组相比,治疗1组、治疗2组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均升高,血清VEGF水平均降低(P<0.05);两组治疗组的上述指标比较,差异无统计学意义(P>0.05)。术后2年、3年,治疗1组、治疗2组的复发率均低于对照组(P<0.05),治疗2组复发率低于治疗1组(P<0.05)。治疗1组、治疗2组的不良反应发生率均低于对照组(P<0.05),治疗2组的不良反应发生率低于治疗1组(P<0.05)。结论马归液口服加膀胱灌注的“内服外治”法联合GEM膀胱灌注治疗NMIBC,能有效提高CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)水平,降低血清VEGF水平,改善免疫系统,减少复发风险和不良反应,临床应用安全有效。

Synthesis of CA_(6)/AlON composite with enhanced slag resistance

Different amounts of AlON have been introduced in calcium hexaaluminate(CA_(6)) using two approaches, that is, one-step and twostep methods, to improve the slag resistance of CA_(6). A one-step method can directly sinter the mixtures combining Al_(2)O_(3), CaCO_(3), and Al in flowing nitrogen, in which AlON clusters are always formed because of the poor wettability of Al by Al_(2)O_(3), leading to the high porosity of CA_(6)/AlON composite. In a two-step method, CA_(6)and AlON are prepared separately and then mixed and sintered in flowing nitrogen. Compared with the sample prepared by the one-step method, CA_(6)and AlON in composite by the two-step method are more uniformly distributed,and the optimized amount of AlON added is 10wt%. The slag corrosion and penetration test shows that the CA_(6)/AlON composite using the two-step method exhibits superior slag corrosion protection. The promoted effect of AlON on slag penetration and corrosion resistance is also discussed.

一种精确监测低灌注下无创血压的前端采集设计

本研究针对现有无创血压监测设备采集前端无法实现低灌注信号准确监测的情况,提出一种基于恒定容积法的低灌注血压精确监测的指尖前端采集方案,并基于动物实验,研究了低灌注情况下光电脉搏波及压力脉搏波信号精确采集对血压准确检测的关键影响。6个动物(猪)实验样本的数据分析结果显示,本研究设计的采集前端在低灌注状态下,连续无创血压监测精度可控制在±10 mmHg内,且血压波动追踪相关性大于80%。基于本研究进行低灌注下的无创血压监测在重灾现场、重症临床监护、慢病监护等方面具有重要意义。