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基于果蝇周期蛋白PER调控网络构建的两导数Runge-Kutta算法

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南京农业大学学报 2014年第3期37卷 152-158页

作者：程小昊刘雪萍 Ibrahim hussein musa 游雄南京农业大学理学院江苏南京210095

为更准确地模拟基因调控网络的动力学行为,考虑采用新的两导数Runge-Kutta模拟算法。这种数值算法的特点是在格式中融入了真实解的二阶结构,使得模拟结果更为精确。与通用的经典四级四阶Runge-Kutta算法RK4相比,二级四阶两导数Runge-Ku... 详细信息

为更准确地模拟基因调控网络的动力学行为,考虑采用新的两导数Runge-Kutta模拟算法。这种数值算法的特点是在格式中融入了真实解的二阶结构,使得模拟结果更为精确。与通用的经典四级四阶Runge-Kutta算法RK4相比,二级四阶两导数Runge-Kutta算法TDRK2s4具有3个优势:1)构造简单,易于编程实现;2)计算成本小,RK4每步需要计算4次非线性函数,而TDRK2s4只需要计算3次;3)存储空间小,RK4方法需要4个内级存储单元,而TDRK2s4只要2个。TDRK2s4用于模拟具有持续振荡特征的果蝇周期蛋白PER与per mRNA负反馈调控网络。与RK4相比较,对不同步长(h=1/2,1/4,1/8,1/16),TDRK2s4的误差远小于RK4的误差;而且TDRK2s4对大步长(h=1/2)的误差远小于RK4对小步长(h=1/16)的误差。对固定步长(h=1/4),随着模拟区间的延长,TDRK2s4的累积误差增长十分缓慢,而RK4的累积误差增长很快。对不同步长(h=1/2,1/4,1/8,1/16),TDRK2s4计算耗费的CPU时间也明显少于RK4。TDRK2s4的模拟效率远高于RK4。结论:当基因调控网络微分方程组右端函数的导数容易得到时,TDRK算法比传统的RK算法更适用于大步长、长时间的高效数值模拟。

关键词：果蝇周期蛋白两导数Runge-Kutta算法精度效率

Explanation of Pressure Effect for High Temperature Superconductors Using Pressure Dependent Schrodinger Equation and String Theory

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Natural Science 2020年第1期12卷 28-34页

作者： Einas Mohamed Ahmed Mohamed Nagwa Idriss Ali Ahmed musa Ibrahim Babiker hussein Rasha Abd Elhai Mohammad taha Mohammed Idriss Ahmed Mubarak Dirar Abd-Alla Department of Physics University College (Turaba) Taif University Taif KSA Department of Physics and Mathematics Hantoub Faculty of Education Algezira University Wad Madaniin-Hantoub Sudan Department of Physics Faculty of Science & Art (Dariyah) Qassim University Al-Mulida KSA Department of Physics and Mathematics Faculty of Education Albutana University Rufaa Sudan Department of Physics Faculty of Science & Art Dariyah University Buljurashi KSA Department of Physics College of Science Majmaah University Majmaah KSA Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan

A pressure dependent Schrodinger equation is used to find the conditions that lead to superconductivity. When no pressure is exerted, the superconductor resistance vanishes beyond a critical temperature related to the repulsive force potential of the electron gass, where one assuming the electron total energy to be thermal, where applying mechanical pressure destroys Sc when it exceeds a certain critical value. However when the electron total energy is an assumed to be that of the free electron model and that the pressure is thermal and mechanical, the situation is different. The quantum expression for resistance shows that the increase of mechanical pressure increases the critical temperature. Such phenomenon is observed in high temperature cupper group.

关键词： Pressure Dependent Schrodinger Equation Superconductivity Critical Temperature Pressure High Temperature Superconductor

Six Years Clinical Experience and Surgical Considerations in Management of Cardiac Myxoma in Iraqi Center for Heart Disease—Single Center Experience

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World Journal of Cardiovascular Surgery 2022年第8期12卷 173-183页

作者： Hozhan hussein Blbas Abdulameer Mohsin hussein Muhammad Mahmud Salim Laith Saleh Alkaaby Abdulsalam Y. taha Department of Cardiac Surgery Surgical Specialty Hospital—Cardiac Center College of Medicine Hawler Medical University Erbil Iraq Department of Thoracic and Cardiovascular Surgery College of Medicine University of Baghdad Baghdad Iraq Department of Cardiac Surgery Surgical Specialty Hospital—Cardiac Center Erbil Iraq Department of Cardiac Surgery Iraqi Center for Heart Diseases Baghdad Iraq Department of Thoracic and Cardiovascular Surgery College of Medicine University of Sulaimani Sulaymaniyah Iraq

Background: Cardiac myxomas are the most frequently encountered benign cardiac tumors that if left untreated are inexorably progressive and potentially fatal. Surgery is the only way of treatment, and if not treated with the right surgical technique recurrence occurs. Objectives: In this single center study we documented the patterns of presentation, localization, surgical approaches and outcome of cardiac myxomas. Methods: This is a retrospective study of 20 patients who underwent surgical removal of atrial myxoma from January 2010 to December 2015. All patients underwent general investigations, and echocardiography was performed on all patients and surgery was done using extracorporeal circulation and mild hypothermia. Results: The ages of the patients ranged from 14 years to 71 years, with a mean of 51.45 years. Most myxomas (75%) originated from left atrium, 20% from right atrium and biatrial in 5% of cases. The male-to-female ratio was 1:2.3 (14 females and 6 males). Myxomas were more common in blood group A+ and B+. Chief complaints were dyspnea (70%) and palpitation (50%). The majority of masses were attached to the interatrial septum (65%) and four of cases (20%) arose from the lateral wall. Right atrial trans-septal incision was used in 55% of cases. No recurrence was recorded in our study. Six patients had postoperative complications, mainly in the form of arrhythmia (3 cases), bleeding (0ne case) and renal failure (one case) which resulted in the death of the patient. Conclusions: Cardiac myxoma excision account for a very small percentage of cardiac procedures. Immediate surgical treatment is indicated because of high risk of embolization and sudden death. Cardiac myxomas can be excised with a low rate of mortality and morbidity. Follow-up examination, including echocardiography, should be performed regularly.

关键词： Atrial Myxoma Cardiac Tumors Cardiac Surgery

Role of sedimentation in continental rifting from comparing two narrow rift valleys the Salton Trough and Death Valley-California

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Natural Science 2011年第11期3卷 927-935页

作者： Diane Doser musa hussein Laura F. Serpa Aaron A. Velasco 不详

To unravel the forces and better understand the processes that drive continental rifting, and to understand the role of sedimentation in promoting the rifting process, we compare;the different geological features of two narrow rifts, the Salton Trough and Death Valley, California. According to our models, the Moho is 22 km deep to the southwest of the Salton Sea on US-Mexico border and it deepens to 30 km in the region west of the Salton Trough. In Death Valley, the Moho is 24 km deep in the central part of the basin and it deepens to 32 km outside of the basin. The dome shaped Moho in both rifts is suggested to be primarily the product of magmatic activity in the lower crust and upper mantle. Death Valley is narrow rift in the initial stage of rifting with several sedimentary basins 2 - 4 km deep. In Death Valley magmatic (thermal) forces appears to drive the rifting process. The Salton Trough is wider than Death Valley and is moving toward sea floor spreading. The depth of the sedimentary basins ranges from 8 - 10 km and a combination of thermal and sedimentation appears to drive rifting processes in the Salton Trough.

关键词： Crustal Models Data Incorporation Magmatic Underplating Narrow Rifts

Comparative Study between Endoscopic Ultrasonography and Transabdominal Ultrasonography in the Assessment of Pancreatobiliary Diseases (with Literatures Review)

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Open Journal of Gastroenterology 2016年第2期6卷 17-30页

作者： taha Ahmed M. Alkarboly Mohammad Omer Mohammad Hiwa Abubaker hussein Surkew Lateef Mahummod Kurdistan Centre for Gastroenterology & Hepatology (KCGH) Sulaimani Iraqi Kurdistan

Background: Endoscopic ultrasonography (EUS) and transadominal ultrasonography (TUS) are two imaging investigations which can be used to assess pancreatobiliary status, although both of these imaging techniques are operator and machine dependent, but they have different sensitivity and specificity in detecting pancreatobiliary diseases. Objective: To compare the diagnostic value of EUS versus TUS in the assessment of pancreatobiliary diseases. Patients and Methods: This study was conducted in KCGH (Kurdistan Center for Gastroenterology and Hepatology) in Sulaimani city. Iraqi Kurdistan;the duration of study was 14 months and conducted after approval of Iraqi board ethical committee. One hundred cases were enrolled in the study: 52 of them were females and 48 were males;their ages ranged between 16 - 90 years;informed consent was taken from all patients;all patients underwent proper clinical evaluation;TUS, EUS and Oesophagogastroduodenoscopy (OGD), and in some of them (25 patients) Endoscopic Retrograde Cholangiopancreatography (ERCP), CT scan of abdomen and laboratory investigations were done. Results: EUS detected more cases with common bile duct (CBD) dilatation, CBD stones and pancreatic space occupying lesion (SOL) than TUS, but the differences in the results were not statistically significant. Also EUS detected more cases of intra-abdominal lymph nodes (LNs) and ampullary/peri-ampullary neoplasms than TUS and the differences in the results were statistically significant. Conclusions: Eus is more sensitive than TUS in diagnosing CBD dilatation;it has higher sensitivity than TUS in suspected pancreatobiliary neoplasms;furthermore, EUS can be used for staging and resectability assessment of pancreatobiliary neoplasia.

关键词： EUS TUS ERCP Pancreatobiliary Diseases KCGH Sulaimani Iraqi Kurdistan

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生物微分方程的保结构数值方法

生物微分方程的保结构数值方法

作者：穆萨（Ibrahim hussein musa Tahir）南京农业大学

学位级别：硕士

常微分方程组是摹写生物系统复杂动力学的强有力的数学工具之一.常微分方程给出生物系统中各个量随时间的变化率,这些变化率表达为各个量的函数.生物学中大部分情况下常微分方程的解析解不能求得,这时候要探究生物系统复杂性的话,数值... 详细信息

常微分方程组是摹写生物系统复杂动力学的强有力的数学工具之一.常微分方程给出生物系统中各个量随时间的变化率,这些变化率表达为各个量的函数.生物学中大部分情况下常微分方程的解析解不能求得,这时候要探究生物系统复杂性的话,数值解就变得尤为重要了.到目前为止,基因调控网络的微分方程大都是用经典的Runge-Kutta （RK）方法求解.然而,通用的RK方法没有考虑到待模拟系统的特殊结构,并且不能有效地表现其动力学特性,在长时间模拟时尤为如此.本文的目的就是研究适应于生物系统物理结构的一些新的保结构数值方法。本文分为四章.第一章概述三个生物系统的常微分方程模型：Lotka-Volterra捕食者与被捕食者系统,基因调控系统、细胞生物学中典型的p53-Mdm2蛋白质系统.后面几章中我们将对这几个模型进行数值模拟,同时还会探究其动力学结构和保结构特性.第二章将Lotka-Volterra系统转成Hamilton系统,并用两个高效的辛方法对其进行数值积分.然后我们就可以看到这些数值方法的高效性.第三章针对基因调控系统的驻态结构,建立了一类新的指数Runge-Kutta方法（ex-pRK）.以传统的RK方法为基础,我们可以自然地构造出expRK方法.在对单基因、双基因和p53-Mdm2调控系统的数值积分中,我们可以看出expRK法比传统的RK方法更为准确.不仅如此,对于非刚性双基因调控系统来说,expRK方法比文献中一些著名的指数RK方法的有更高的计算效率.在第四章中,为了适应一些基因调控振子的极限环结构,我们考虑修正传统的RK方法使之适用于该系统的振荡性质.建立了修正RK方法的相拟合和振幅拟合条件,构造了几个高阶的相拟合和振幅拟合RK（FRK）方法,计算了它们的误差系数和误差常数.对双基因调控系统的数值模拟结果表明,在长时间模拟中,FRK方法比传统的RK方法更准确,更高效.一个重要发现是：FRK方法的最佳拟合频率不仅依赖于问题,还依赖于方法本身.

关键词：生物系统 Hamiltonian系统辛方法驻态极限环指数Runge-Kutta方法相拟合振幅拟合

The Role of Endoscopic Retrograde Cholangiopancreatography (ERCP) in the Management of Intra-Biliary Rupture of Liver Hydatid Cysts (IBRH): Follow-Up of 12 Cases

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Case Reports in Clinical Medicine 2014年第9期3卷 533-543页

作者： Mohammad Abdulrahman Alshekhani taha A. Alkarbuli Naser Abdullah Mohammed Alqazi Hiwa A. hussein Qalandar H. Kasnazan Ali hussein Ali Kurdistan Center for Gastroenterology & Hepatology Asulaimaneyah Iraqi Kurdistan Iraq

Background: Intra-biliary rupture of hydatid cyst [IBRH] is not a rare complication of hydatid disease of the liver and surgery until recently is the only definitive treatment. With the introduction of ERCP preoperatively or postoperatively there was a great reduction in the operative complications. There were reports in which the ERCP was the sole treatment of this condition. Objective: To evaluate role of ERCP in the management of cases of IBRH. Design: A retrospective study of 7 cases of IBRH and prospective study of 5 cases of IBRH managed by ERCP. Setting: The ERCP Unit of Kurditan Center for Gastroenterology & Hepatology, Asulaimaneyah-Iraqi, Kurdistan, Iraq. Main Outcome Measurements: Improvement in the symptoms, obstructive liver functions pattern and ultrasonic findings in these patients following ERCP management. Methods: This is a study of 12 cases of IBRH managed by ERCP in the Kurdistan Center of Gastroenterology (KCGE) in Asulaimaneyah-Iraq, from 2007-2010. Seven cases of these were studied retrospectively from the available information on the center computers and on follow-up of these patients, while the other five patients were studied prospectively during the study period. We collected the available information: laboratory investigations, trans-abdominal ultrasonography (TAUS), computed tomography (CT) or magnetic resonance images (when available), before and after ERCP. We depended on the liver functions, trans-abdominal ultrasound and the clinical presentation before and after the ERCP;some patients were contacted via mobile phone for follow-up. Results: Cases were more males than females (58% vs 42%);most were from the ages between 30 - 50 years. The clinical presentation was fever, jaundice, itching and right hypochondrial pain in most patients. The liver function tests were obstructive pattern with elevated direct bilirubin and alkhaline phosphates in most patients. The trans-abdominal ultrasound revealed dilated common bile duct and single liv

关键词： Intra-Biliary Rupture of Hydatid Cyst ERCP Obstructive Jaundice

Five-year retrospective hospital-based study on epidemiological data regarding human leishmaniasis in West Kordofan state,Sudan

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World Journal of Clinical Infectious Diseases 2022年第2期12卷 61-68页

作者： Abdullah Abdulslam Abdullah musa Ahmed Ahmed Gadeed Adam Eltayeb Safa Ahmed Suad Hamad Mohammed hussein Department of Biomedical Sciences Faculty of Veterinary SciencesUniversity of GadarifGadarif 208Sudan Department of Reproductive Health Sciences Pan African University Life and Earth Sciences InstituteUniversity of IbadanIbadan 119Oyo StateNigeria Department of Veterinary Surgery and Anaesthesia Faculty of Veterinary MedicineALsalam UniversityAl-fula 120West Kordofan StateSudan Environmental Studies and Research Center Al-Salam UniversityAl-fula 120West Kordofan StateSudan Al-Sadaga Hospital Al-fula 124West Kordofan StateSudan Department of Zoonotic Disease and Disease Control Ministry of Animal ResourcesAl-Hamadi 215South Kordofan StateSudan Department of Statistics and Health Information Ministry of HealthAlfula 127West Kordofan StateSudan

BACKGROUND Leishmaniasis is a neglected zoonotic disease,endemic in *** this disease is very important to inform the health care policymakers and the governments to apply proper health and economic *** To find out the frequency and distribution of human leishmaniasis based on sex and age for 5 years in the West Kordofan state,*** A 5-year retrospective study from 2016 through 2020 was carried out using local hospital records of leishmaniasis *** positive results were recorded after performing at least one of the following leishmaniasis standard tests:direct agglutination test,enzyme-linked immunosorbent assay and leishmania skin *** sex and age of each patient were *** collected data were analyzed using STATA package version *** A total of 162443 patient records from 2016 to 2020 were *** these,4.39%were found to be positive for *** disease has been more common in males(65.3%)than in females(34.7%).The highest reported prevalence(6.58%)was in patients 15-44 years,and the lowest prevalence(1.95%)was among patients≥65 *** The results of the current study indicate that leishmaniasis is endemic in the study area even though the numbers of patients in the 5 consecutive years were *** addition,the disease was common in males and *** interpretation of these findings should take into consideration the absence of information about some important confounding factors.

关键词： Epidemiology Human Leishmaniasis West Kordofan Sudan Endemicity

Analysis on the Origin and Phylogenetic Status of Tong Sheep Using 12 Blood Protein and Nonprotein Markers

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Journal of Genetics and Genomics 2007年第12期34卷 1097-1105页

作者：孙伟常洪杨章平耿荣庆角田健司任战军陈宏宇 musa H.hussein 扬州大学动物科学与技术学院扬州225009 日本昭和大学医学部西北农林科技大学杨陵712100

This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene constitution of blood protein and nonprotein types of Tong sheep. Twelve genetic markers were examined by starch-gel electrophoresis and cellulose acetate electrophoresis. Polymorphism in Tong sheep was found at the following 10 loci, transferrin （Tf）, alkaline phosphatase （Alp）, leucine aminopeptidase （Lap）, arylesterase （Ary-Es）, hemoglobin-β （Hb-β）, X-protein （X-p）, carbonic anhydrase （CA）, catalase （Cat）, malate dehydrogenase （MDH）, and lysine （Ly）, whereas, albumin （A1） and postalbumin （Po） loci were monomorphic. Genetic approach degree method and phylogenetic relationship clustering method were used to judge the origin and phylogenetic status of Tong sheep. Results from both methods maintained that Tong sheep belonged to the ＂Mongolia group＂, and Mongolia sheep was the origin of Tong sheep. This was also supported by the history of Tong sheep breeding. Compared to the phylogenetic relationship clustering method, the genetic approach degree method was more reliable for the extraction from East and South of Central Asia, and was more effective in reflecting the breeding course of Tong sheep.

关键词： Tong sheep origin phylogenetic status genetic approach degree phylogenetic relationship clustering