Hemoglobin loss method calculates blood loss during pancreaticoduodenectomy and predicts bleeding-related risk factors

BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is no accurate,objective me-thod to evaluate the amount of blood loss in PD patients.We retrospectively analyzed the clinical data of 341 patients who underwent PD in Shandong Provincial Hospital from March 2017 to February 2019.According to different surgical methods,they were divided into an open PD(OPD)group and a laparoscopic PD(LPD)group.The differences and correlations between the in-traoperative estimation of blood loss(IEBL)obtained by visual inspection and the intraoperative calculation of blood loss(ICBL)obtained using the Hb loss method were analyzed.ICBL,IEBL and perioperative calculation of blood loss(PCBL)were compared between the two groups,and single-factor regression analysis was performed.RESULTS There was no statistically significant difference in the preoperative general patient information between the two groups(P>0.05).PD had an ICBL of 743.2(393.0,1173.1)mL and an IEBL of 100.0(50.0,300.0)mL(P<0.001).There was also a certain correlation between the two(r=0.312,P<0.001).Single-factor analysis of ICBL showed that a history of diabetes[95%confidence interval(CI):53.82-549.62;P=0.017]was an independent risk factor for ICBL.In addition,the single-factor analysis of PCBL showed that body mass index(BMI)(95%CI:0.62-76.75;P=0.046)and preoperative total bilirubin>200μmol/L(95%CI:7.09-644.26;P=0.045)were independent risk factors for PCBL.The ICBLs of the LPD group and OPD group were 767.7(435.4,1249.0)mL and 663.8(347.7,1138.2)mL,respectively(P>0.05).The IEBL of the LPD group 200.0(50.0,200.0)mL was slightly greater than that of the OPD group 100.0(50.0,300.0)mL(P>0.05).PCBL was greater in the LPD group than the OPD group[1061.6(612.3,1632.3)mL vs 806.1(375.9,1347.6)mL](P<0.05).CONCLUSION The ICBL in patients who underwent PD was greater than the IEBL,but there is a certain correlation between the two.The Hb loss method can be used to evaluate intraoperative blood loss.A history of diabetes,preoperative bilirubin>200μmol/L and high BMI increase the patient's risk of bleeding.

Electronic States of Difluorocarbene Calculated by Multireference Configuration Interaction Method

We investigate the geometries and energies of seven electronic states X-1A1, A1B1, a-3B1, B-1A2,b-3A2, C1B2 and c-3B2 of CF2 carbene using internally contracted multireference configuration interaction methods including Davidson correction （icMRCIq-Q） with different basis sets aug-cc-pVXZ （X=T, Q, 5）. For the first time, the potential energy curves of electronic states of CF2 related icMRCI＋Q/aug-cc-pVTZ level. The ab initio results will and dynamics of electronic states of CF2 radical. to the lowest dissociation limit are calculated at the further increase our understanding of the structures

Absolute Internal Energy of the Real Gas

The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations among gas temperature T, pressure p and mass-specific volume v=V/M, the mass exists as a uniform gas of freely-moving particles having positive values U or as more or less structured matter with negative values U. In the regions U>0?above the critical point [Tc , pc , vc] it holds that p(T,v)>pc and v>vc, and below the critical point it holds that p(T,v)c and v>vv , where vv is the mass-specific volume of saturated vapor. In the adjacent regions with negative internal energy values Uc is the line of equal positive and negative energy contributions and thus represents a line of vanishing internal energy ?U=0. At this level along the critical isochor the ever present microscopic fluctuations in energy and density become macroscopic fluctuations as the pressure decreases on approaching the critical point;these are to be observed in experiments on the critical opalescence. Crossing the isochor vc from U>0 to UΔU>0 happens without any discontinuity. The saturation line vv also separates the regions between U>0 and U , but does not represent a line U=0. The internal-energy values of saturated vapor Uv and condensate Ui can be determined absolutely as functions of vapor pressure p and densities (M/V)v and (M/V)i , repectively, yielding the results Uiv, U=Ui+Uvc and U=Ui=Uv=0 at the critical point. Crossing the line Vv from U=Uv>0 to U=Uv+UiΔU=-Ui>0 to be removed from the particle system. The thermodynamic and quantum-mechanical formulations of the internal energy of a particle system only agree if both the macroscopic and microscopic energy scales have the same absolute energy reference value 0. Arguments for the energy reference value in the state of transition from bound to freely- moving particles in macroscopic classical and microscopic quantum particle systems are discussed.

Comparison of Calculated Fit and Experimental Calculations of Average Dose Deposited in Aluminum by High Energy Electron Beams

This paper presents the formalism for absorbed dose determination to Aluminum in high-energy electron beams using Rhodotron accelerator. Depth dose curve for Aluminum at electron energy of 10 MeV was calculated. The calculated curve in the model as a function of the depth is compared to the experimental. The agreement of the final results remained well within the expected acceptable range. The calculated values of dose-to-Aluminum are completely fit with the measured values in the range of 0.07% for electron energy of 10 MeV.

2-羟基咪唑在气相和水中的异构平衡和质子迁移的从头算计算和Monte Carlo模拟

采用从头算方法在MP2/6-31+G*水平上研究了2-羟基咪唑分子在孤立分子和一水合物的异构体的相对稳定性和可能的质子迁移反应,分析了一个水分子的参与对2-羟基咪唑分子异构体的相对稳定性和质子迁移速率的影响,采用MonteCarlo模拟方法研究了反应体系在水溶液中反应的溶剂化效应.结果表明:2-羟基咪唑分子的孤立分子和一水合物的最稳定异构体相同,都为酮式.直接质子迁移反应在水溶液中活化能垒有轻微增加,但产物能量得到降低;水助催化质子迁移反应在水溶液中的活化能垒和产物能量都得到明显降低.综合气相和水相的计算结果,2-羟基咪唑水助催化的质子迁移反应较易进行,且在水溶液中进行容易,可以很容易被实验观察到.

燃煤固体产物中含钙矿物的迁移与多相反应

燃煤灰渣中含钙矿物的组成和多相反应与灰渣活性密切相关。该文对SBF试验台上煤粉与添加剂混烧后的灰样进行XRD分析,并采用F*A*C*T软件包对煤和添加剂组成的多组分系统进行热力学计算,探讨了不同条件下灰渣中含钙矿物的组成特性。结果表明,燃煤灰渣中含钙矿物主要参与固相反应和固硫反应,固相反应生成的含钙矿物主要包括CaO-SiO2、CaO-Al2O3、CaO-Fe2O3以及CaO-SiO2-Al2O3类矿物。随着CaO含量的增加,灰渣中生成的最主要矿物从莫来石→钙长石→钙黄长石→硅酸二钙过渡。在CaSO4稳定存在的温度范围内,固硫反应比固相反应更易进行;随着温度的升高,CaSO4发生分解或者进一步反应生成硫铝酸钙或硫硅酸钙从而使得钙向硅酸盐矿物迁移。

Analysis of Ringing and Noise in FE and FDTD Calculated Acoustic Pulse Profiles

Ringing, i.e. the emergence of an oscillatory tail behind a wave pulse as it propagates through a medium, is a pervasive artefact in FE and FDTD calculated waveforms. It is known to be a consequence of numerical dispersion arising from the discretization of the equations of motion. The use of an irregular mesh in a FE code has the further consequence of rendering the displacement field increasingly noisy with distance behind the wave front. In this paper these effects are illustrated using the commercial FE package ABAQUS with square and irregular triangular meshes to calculate the progress of a longitudinally polarized Ricker pulse along the axis of a cylindrically shaped aluminium specimen. We are able to give a precise analytical account of the evolution of ringing on the basis of a low order approximation for the dispersion relation of the discretized equations of motion. A qualitative account is provided of the generation of noise in the use of an irregular triangular mesh.

Using GPU to calculate electron dose for hybrid pencil beam model

Hybrid pencil beam model(HPBM) offers an efficient approach to calculate the three-dimension dose distribution from a clinical electron beam.Still,clinical radiation treatment activity desires faster treatment plan process.Our work presented the fast implementation of HPBM-based electron dose calculation using graphics processing unit(GPU).The HPBM algorithm was implemented in compute unified device architecture running on the GPU,and C running on the CPU,respectively.Several tests with various sizes of the field,beamlet and voxel were used to evaluate our implementation.On an NVIDIA GeForce GTX470 GPU card,we achieved speedup factors of 2.18- 98.23 with acceptable accuracy,compared with the results from a Pentium E5500 2.80 GHz Dual-core CPU.

水平井射孔完井表皮系数分解计算方法

近井地带的表皮系数是评价油气井产能和完井效率的重要参数。由不稳定试井法确定的表皮系数,是一个既包括钻井液、完井液对近井地带储层污染与堵塞的影响,又包括钻井、完井的不完善和增产措施影响的总表皮系数,不能评价某一施工环节的好坏。针对完井施工过程中如何计算各表皮系数以引导完井现场施工的问题,提出了一种新的分解计算水平井表皮系数的方法,即:将水平井总表皮系数分解为打开程度表皮系数Spt、射孔总表皮系数Spf、钻井污染表皮系数Sd方法,并反推出各分项表皮系数的计算方法。它无需压力恢复曲线或压降曲线,仅利用DST数据即可计算。通过DST测试资料预测油井各施工环节的污染情况,以便选择最佳的钻井、完井方法以及优化完井参数并用于指导初期增产施工。

Low-lying electronic states of CuN calculated by MRCI method

The high accuracy ab initio calculation method of multi-reference configuration interaction（MRCI） is used to compute the low-lying eight electronic states of CuN.The potential energy curves（PECs） of the X;∑;,1;Π,2;∑;,1;△,1;△,1;∑;,1;Π,and;∑;in a range of R=0.1 nm-0.5 nm are obtained and they are goodly asymptotes to the Cu（;S;） + N（;S;） and Cu（;S;）+N（;D;） dissociation limits.All the possible vibrational levels,rotational constants,and spectral constants for the six bound states of X;∑;,1;Π,2;∑;,1;△,1;∑;,and 1;Π are obtained by solving the radial Schrdinger equation of nuclear motion with the Le Roy provided Level 8.0 program.Also the transition dipole moments from the ground state X;∑;to the excited states 1;Π and 2;∑;are calculated and the result indicates that the 2;∑-X;∑ transition has a much higher transition dipole moment than the 1;Π-X;∑;transition even though the l;Π state is much lower in energy than the 2;∑;state.

A method to calculate the acetabular cup anteversion after total hip replacement based on 3D coordinate system

Aim: To explore an accurate method to calculate acetabular cup anteversion after total hip arthroplasty. Method: 1) A 3D coordinate system was established with the center of the hip joint rotation center base as coordinate center. The acetabular exit plane and Pettersson formula acetabular anteversion and Riten Pradhan formula acetabular anteversion and acetabular true anteversion were drawn;2) Determine the mathematical expression of Pettersson formula acetabular anteversion α and Riten Pradhan formula acetabular anteversion β in the coordinate system. The true acetabular anteversion is projection angle of Pettersson formula acetabular anteversion α on cross-section in the presence of acetabular abduction δ, determining mathematical expression of the acetabular anteversion θ by trigonometric functions. Results: Real acetabular cup anteversion θ = arctg (tgβ/cosδ). Conclusion: The true acetabular cup anteversion and Pettersson formula anteversion and Riten Pradhan for mula anteversion were quite different. The difference was increased with the acetabular cup abduction angle increased. The formula was simple and accurate and worthy of clinical reference.

A History of the Urban Underground Tunnel (4000 B.C.E. - 1900 C.E.)

Generally hidden from public view, out of our daily thoughts, and literally under our feet, are myriad urban underground tunnels that make our modern megacities possible. From their ancient beginnings in antiquity, as a means of supplying fresh water and draining waste water from cities, underground tunnels evolved into a means of providing high capacity rail mass transit in our most densely populated urban centers. This paper provides a broad overview of the evolution of urban tunnels across a 6000 year time span and includes the specific engineering formulas/computations for the earliest 19th century subways/infrastructure projects based on the Roman vaulted arch tunnel.

基于蒙特卡罗方法的三维燃耗计算研究

采用通过编写连接MCNP程序和ORIGEN2程序的接口处理程序的方法进行快中子系统的燃耗计算。由MCNP、ORIGEN2、接口处理程序和截面文件组成的软件系统可用于燃料或堆芯非均匀布置快中子系统的燃料同位素成分和燃耗反应性损失计算,在燃耗反应性损失计算中采用了伪裂变产物的方法。介绍程序系统的研制情况,并给出用该软件系统计算中国实验快堆首炉堆芯和OECD/NEAMOX燃料快堆基准题的燃耗计算结果。

风景区环境容量的计算方法——以山海关五佛森林公园为例

目的通过对风景名胜区的环境容量进行测算,得出旅游规模和生态保护之间的量比关系,将游人规模控制在科学合理的环境容量范围内,做到既可保证游人的风景旅游活动质量,又能够对风景资源进行保护.方法根据风景名胜区景观游览形式的不同,分别采用线路容量计算法、面积容量计算法、瓶颈容量计算法(卡口法)进行环境容量的计算.结果推算出风景区的日环境容量和年环境容量,为风景区的旅游产业的开发和旅游服务设施的建设提供科学合理的依据.结论风景名胜区中环境容量的计算是预测旅游产业的发展、合理控制游人规模、制定旅游经营决策的科学依据,对风景区相关旅游产业的开发、经济与社会效益的提高以及可持续发展的实现,都具有极为重要的意义.

连杆热模锻全过程的仿真分析及模具寿命预测

在考虑连杆热模锻模具的材料性能和工况条件基础上,采用有限元分析软件Msc.Superform对连杆热模锻全过程进行了非线性、大变形热机械耦合分析。实现了对连杆热模锻模具关键部位的弹塑性变形的全过程动态模拟仿真,得到了温度场、等效塑性应力应变场在时间和空间上的分布规律,研究结果符合实际情况,具有现实意义。在此基础上,运用CoffinMansion公式对所计算的模具寿命进行了预测,其结果与实际应用中的模具寿命基本一致,为进一步研究不同工况下热模锻成形控制和终锻成形模具结构设计提供了理论依据。

软土地基中插入式大直径薄壁圆筒结构的一种简化数值计算方法

简述了对插入式大直径薄壁圆筒进行数值分析采用的力学机制,用弹簧元模拟薄壁圆筒与地基土体接触面间的连接所形成一种简化的数值计算模型,运用大型通用有限元软件ANSYS进行二次开发后对其进行数值计算与分析,比较了对筒内外淤泥粘土采用不同加固处理方法以及考虑相邻圆筒间采用不同边界约束条件时,对圆筒的应力和稳定性的影响。通过实例计算,验证了该数值模型的有效性与可行性,并得出一些有益结论。

论矿物材料计算与设计

矿产资源产业是国民经济的基础产业,非金属矿产是重要的固体矿产之一,80%的矿物用于材料工业,矿物加工是矿产资源高效利用、制备矿物材料的重要加工技术环节,矿物材料是国民经济中高新技术材料的重要组成,材料科学及矿物材料学科的发展,为矿物材料计算与设计理论的提出奠定了实际基础。借鉴材料设计与计算的理论和方法,在总结、分析和研究矿物加工及矿物材料制备方面大量的理论研究和实际成果的基础上,提出了矿物材料计算与设计及功能性矿物材料、复合材料化学改性药剂分子设计与模拟的学术思想,论述了矿物材料计算与设计的基本科学技术问题、研究内容、相关学科体系、研究层次及其学科地位。其意义在于:使矿物加工工程学科发展和功能性矿物材料的研发,建立在基本科学原理基础之上,将矿物加工工程学科的主要研究内容统一在总体的方向、目标之内,横向拓展了相关学科理论的研究范围;根据矿物结构、组成,通过设计与计算,对矿物材料性能进行预测、预报,进而为制备提供最佳技术路线;对于已知性能的矿物材料优化制备路线,系统分析各种矿物的结构与组成及其所具备固有性质,针对各种材料性质要求,排列对应关系,为复合材料的制备奠定基础,进而实现矿物资源的高效开发和利用,同时,使得材料设计或计算材料的学科基?

用NRTL方程计算含离子液体体系的汽液平衡

离子液体作为环境友好溶剂在反应和分离过程中具有良好的应用前景, 含离子液体体系汽液平衡的计算及模型化研究具有重要的理论和实际意义. 采用非电解质溶液NRTL 方程表示溶液的非理想性, 关联了[bmim] [PF6] H2O及[C8mim] [PF6] H2O二元体系的等温汽液平衡, 关联误差在2%之内; 预测了这些体系在其他温度下的汽液平衡, 预测的总平均误差均在5%之内. 通过关联不同温度下有机物在离子液体C8H14S2O4F6N3 和C9H16S2O4F6N3 中的无限稀释活度因子的实验数据, 得到了有关NRTL方程的二元作用参数, 在此基础上预测了离子液体对二元共沸体系汽液平衡的影响. 结果表明, 含离子液体体系的汽液平衡可以采用传统的非电解质溶液模型如NRTL方程来描述, 离子液体的“盐效应”可以显著改善组分的相对挥发度甚至消除共沸现象.

复杂岩性裂缝—孔隙型储层孔隙度计算方法研究

酒泉盆地青西坳陷青南凹陷柳沟庄—窟窿山构造下沟组储层岩性主要为低孔、低渗砂砾岩类和泥云岩类,岩石矿物成分复杂、泥质含量高、黄铁矿富集、裂缝类型及组合形式复杂,属典型复杂岩性裂缝—孔隙型储层。在这类复杂岩性裂缝—孔隙型储层中,自然伽马等测井曲线不能很好指示地层中的泥质含量,常规测井资料难以准确识别地层的岩石矿物成分,单条测井曲线与岩心孔隙度之间的关联度低,采用常规的孔隙度测井计算方法存在明显的缺陷,孔隙度计算精度远远不能满足储层评价和储量计算要求。文章利用岩心分析数据和测井信息等资料,采用3层BP神经网络进行学习训练,得到砂砾岩岩类和泥云岩岩类的孔隙度计算模型。利用该模型计算储层孔隙度,其结果与岩心分析孔隙度比较,平均误差小于1.5%,能满足储量计算要求。在实际应用中见到良好效果,孔隙度计算精度明显得到提高。

VSC-HVDC稳态特性与潮流算法的研究

该文分析了 VSC-HVDC 的稳态功率特性及控制方式;在 VSC-HVDC 稳态模型的基础上,导出了其适用于牛顿法潮流计算的数学模型,并根据 VSC-HVDC 中电压源换流器(VSC)的控制对象大多为交流侧物理量的特点,提出了一种交直流混合系统潮流的交替求解算法:算法中计及了直流变量的约束条件,当混合系统潮流求解过程中无换流器调制度越界,算法可快速收敛,否则将由于交直流系统间相互影响,致使交替求解次数的增加。算例结果验证了 VSC-HVDC 潮流模型的正确性以及交替求解算法的有效性。该算法为进一步研究含有 VSC-HVDC 的交直流电力系统的潮流控制特性奠定了基础。