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International Journal of Mining Science and Technology 2018年第6期28卷 885-890页

作者： Robert Eades Kyle Perry Catherine Johnson jacob Miller Department of Mining and Nuclear Engineering Missouri University of Science and Technology

The phenomenon of combustible dust explosions is present within many industries. Tests for explosibility of dust clouds per ASTM E1226 use a 20 L explosive chamber that places the combustible dust directly below the dispersion nozzle which generates a thorough mixture for testing purposes. However, in the underground coal mining industry, there are a number of geologic, mining, and regulatory factors that change the deposition scheme of combustible coal dust. This causes the atmosphere of a coal mine to have a variable rock dust-coal dust mixture at the time of ignition. To investigate the impact of this variable atmosphere, a series of lean explosibility tests were conducted on a sample of Pittsburgh Pulverized coal dust. These explosibility tests were conducted in a 38 L chamber with a 5 kJ Sobbe igniter. The 38 L chamber generates a variable air-dust mixture prior to ignition. The test results indicate that the 38 L chamber experiences reduced explosive pressures, and lower explosibility index values when compared to the 20 L chamber.

关键词： Dust explosion Coal mining Coal dust Explosibility testing

THE STOCHASTIC BOUNDARY ELEMENT METHOD IN STATISTICAL ANALYSIS OF MODERATELY THICK PLATES

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Acta Mechanica Solida Sinica 1995年第2期8卷 163-170页

作者： JINAG, am DING, HJ ZHEJIANG UNIV HANGZHOU 310027PEOPLES R CHINA

In this paper a stochastic boundary element method (SEEM) is developed to analyze moderately thick plates with random material parameters and random thickness. Based on the Taylor series expansion, the boundary integration equations concerning the mean and deviation of the generalized displacements are derived, respectively. It is found that the randomness of material parameters is equivalent to a random load, so the mean and covariance matrices of unknown generalized boundary displacements and tractions can be obtained. Furthermore, the mean and covariance of generalized displacements and forces at internal points can also be obtained. A numerical example has been worked out with the method proposed and necessary analysis is made for the results.

关键词： ISOTROPIC MODERATELY THICK PLATES STOCHASTIC BOUNDARY ELEMENT METHOD STATISTICAL ANALYSIS COVARIANCE

Effect of post-thermal annealing on the structural and optical properties of ZnO thin films prepared from a polymer precursor

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Chinese Physics B 2012年第7期21卷 551-558页

作者： Jijoy.P.Mathew George Varghese jacob Mathew Thin Film Research Laboratory Department of PhysicsSt.Berchmans CollegeChanganasseryKerala 686101India Department of Physics Calicut UniversityThenjippalamKeralaIndia

ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.

关键词： stress, band gap, Urbach energy photoluminescence

Single-port versus multi-port cholecystectomy for patients with acute cholecystitis: a retrospective comparative analysis

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Hepatobiliary & Pancreatic Diseases International 2011年第5期10卷 521-525页

作者： Dietmar jacob Roland Raakow Department of Surgery Center for Minimally Invasive Surgery Vivantes Hospital Spandau Neue Bergstrasse 6 13585 Berlin Germany Department of Surgery Vivantes Klinikum Am Urban Dieffenbachstrasse 1 10967 Berlin Germany

BACKGROUND: Trans-umbilical single-port laparoscopic cholecystectomy for chronic gallbladder disease is becoming increasingly accepted worldwide. But so far, no reports exist about the challenging single-port surgery for acute cholecystitis. The objective of this study was to describe our experience with single-port cholecystectomy in comparison to the conventional laparoscopic technique. METHODS: Between August 2008 and March 2010, 73 patients with symptomatic gallbladder disease and histopathological signs of acute cholecystitis underwent laparoscopic cholecystec- tomy at our institution. Thirty-six patients were operated on with the single-port technique (SP group) and the data were compared with a control group of 37 patients who were treated with the multi-port technique (MP group). RESULTS: The mean age in the SP group was 61.5 (range 21-81) years and in the MP group was 60 (range 21-94) (P=0.712). Gender, ASA status and BMI were not significantly different. The number of white blood cells was different before [SP: 9.2 (range 2.8-78.4); MP: 13.2 (range 4.4-28.6); P=0.001] and after the operation [SP: 7.8 (range 3.5-184.8); MP: 11.1 (range 5-20.8); P=0.002]. Mean operating time was 88 (range 34-174) minutes in the SP group vs 94 (range 39-209) minutes in the MP group (P=0.147). Four patients (5%) required conversion to an open procedure (SP: 1; MP: 3; P=0.320). During the follow- up period of 332 (range 29-570) days in the SP group and 428 (range 111-619) days in the MP group (P=0.044), eleven (15%) patients developed postoperative complications (P=0.745) and two patients in the SP group required reoperation (P=0.154). CONCLUSIONS: Trans-umbilical single-port cholecystectomy for beginning acute cholecystitis is feasible and the complicationrate is comparable with the standard multi-port operation. In spite of our good results, these operations are difficult to perform and should only be done in high-volume centers for laparoscopic surgery with experience in sin

关键词： laparoscopic surgery single-port cholecystectomy acute cholecystitis

Dynamic response surface methodology using Lasso regression for organic pharmaceutical synthesis

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Frontiers of Chemical Science and Engineering 2022年第2期16卷 221-236页

作者： Yachao Dong Christos Georgakis jacob Santos-Marques Jian Du Institute of Chemical Process Systems Engineering School of Chemical EngineeringDalian University of TechnologyDalian 116024China Department of Chemical and Biological Engineering and Systems Research Institute Tufts UniversityMedfordMA 02155USA

To study the dynamic behavior of a process,time-resolved data are collected at different time instants during each of a series of experiments,which are usually designed with the design of experiments or the design of dynamic experiments *** utilizing such time-resolved data to model the dynamic behavior,dynamic response surface methodology(DRSM),a datadriven modeling method,has been *** approaches can be adopted in the estimation of the model parameters:stepwise regression,used in several of previous publications,and Lasso regression,which is newly incorporated in this paper for the estimation of DRSM ***,we show that both approaches yield similarly accurate models,while the computational time of Lasso is on average two magnitude *** case studies are performed to show the advantages of the proposed *** the first case study,where the concentrations of different species are modeled directly,DRSM method provides more accurate models compared to the models in the *** second case study,where the reaction extents are modeled instead of the species concentrations,illustrates the versatility of the DRSM ***,DRSM with Lasso regression can provide faster and more accurate datadriven models for a variety of organic synthesis datasets.

关键词： data-driven modeling pharmaceutical organic synthesis Lasso regression dynamic response surface methodology

Repositioning imatinib for spinal cord injury

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Neural Regeneration Research 2015年第10期10卷 1591-1593页

作者： jacob Kjell Lars Olson Department of Neuroscience Karolinska Institutet Department of Physiological Genomics Ludwig-Maximilians-Universität München(LMU)

Efforts to pharmacologically restore central nervous system（CNS）function after injury has historically focused on promoting nerve growth with nerve growth factors such as nerve growth factor（NGF）,neurotrophin 3（... 详细信息

关键词： Repositioning imatinib for spinal cord injury BSCB BBB

Prognosis Factors of Urinary Quality of Life in Parkinson Disease

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Open Journal of Therapy and Rehabilitation 2024年第1期12卷 10-17页

作者： Ngor Side Diagne Sakhi Othman Ababacar Mamadou Gueye Marie Jeanne Sakho Fatou Dialo Mboup amélie Ndeye Makarame Sy Papa Ndiouga Lo Ba Seydina Ousmane Anna Modji Basse Maouly Fall Adjaratou Dieynaba Sow Moustapha Ndiaye amadou Gallo Diop Physical Médicine and Rehabilitation Department Fann Teaching Hospital Dakar Senegal Neurology Department Pikine Hospital Dakar Senegal Physical Médicine and Rehabilitation Department Ibn Rochd Teaching Hospital Casablanca Morocco Physical Médicine and Rehabilitation Department Military Hospital Dakar Senegal Neurology Department Fann Teaching Hospital Dakar Senegal

Introduction: Quality of life in Parkinson disease is not necessary linked to motor symptoms. It’s correlated of overactive bladders and prostatic symptoms. Prognosis factors of urinary quality of life are unknown. Objectives: Our study aims to find prognosis factors of quality of life associated specifically of urinary disorders in PD. Patients and methods: We conducted a transversal, analytic and descriptive study in Physical Medicine, and Neurology departments, Fann Teaching Hospital, Dakar and included patients followed for treatment of PD. Urinary disorders, quality of life and functional autonomy were assessed respectively by Urinary Symptoms Profile (USP), Qualiven Short Form, Schwab and England Scale. Results: 38 patients presented PD, with a mean age of 60.89 ± 13.6 years and sex-ratio of 2.45. Mean duration of PD was 3.1 ± 2.9 years. Urinary disorders were found in 47.36% and dominated by incontinence (88.88%) and overactive bladders (88.88%) which were minor in more than 55%. Quality of life was impaired in 88.88% of cases. Minor forms (43.75%) were predominant and constraint dimension (50%) was the most severely altered. Prognosis factors for quality of life of urinary disorders were PD stages (0.046) and functional autonomy (0.042). Discussion and conclusion: Urinary disorders in PD are common, impaired quality of life, especially the constraint dimension, depends on stage of evolution of PD and functional autonomy of patients.

关键词： Urinary Quality of Life Parkinson Disease Dakar

Interactive Effect of Potassium and Phosphorus on Grain Quality and Profitability of Sunflower in Northwest Pakistan

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Pedosphere 2011年第4期21卷 532-538页

作者： am ANULLAH M.W.KHAN Department of Agronomy Khyber Pakhtunkhwa Agricultural University

A field experiment was conducted using a split plot randomized complete block design with three replications to study the effects of potassium (K) and phosphorus (P) application on sunflower (Helianthus annuus L.) growth at the New Developmental Research Farm of Khyber Pakhtunkhwa Agricultural University in Peshawar,*** levels of K (0,25,50,75,100 and 125 kg K ha-1) were main plots while four levels of P (0,45,90 and 135 kg P ha-1) were *** in both K and P levels enhanced grain oil concentration of *** in P level increased grain protein concentration,while increase in K level decreased grain protein *** oil and protein yields increased significantly with increase in K and P *** increase in oil and protein yields of sunflower was mainly attributed to the improvement in yield components (grains per head,grain weight and head size) and the significant increase in grain *** highest net returns of 297 and 368 US$ ha-1 based on grain and oil yields,respectively,were obtained from a combination of 100 kg K ha-1 + 45 kg P ha-1.

关键词： economic analysis grain yield oil content protein content

Management of symptomatic ureteric stumps laparoscopically

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Asian Journal of Andrology 2001年第2期3卷 147-150页

作者： A.M.Khan S.jacob Department of Surgery King George Hospital Ilford Essex IG1 2HL UKDepartment of Surgery King George Hospital Ilford Essex IG1 2HL UK

Aim: To study the advantage of excision of the distal symptomatic ureteric stumps with the retroperitoneal laparo-scopic approach. Methods: Four patients who had failed to settle their symptoms with the initial conservative man-agement were included in the study. All underwent excision of the distal symptomatic ureteric stumps with the retroperi-toneal laparoscopic approach and then received prophylactic antibiotics. Results: We have achieved better resultsthan those reported in the literature in terms of operating time (mean 1 h 45 min), blood loss ( < 10 mL), postopera-tive recovery (within 12 h) and hospital stay ( < 48 h). Conclusion; Retroperitoneal laparoscopic excision is asafe, simple and effective method in the management of symptomatic ureteric stumps.

关键词： ureter laparoscopy retroperitoneal space

Endemics and endangered species in the biodiversity hotspot of the Shada Mountains, Saudi Arabia

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Journal of Arid Land 2017年第1期9卷 109-121页

作者： jacob THOMAS Mohamed A EL-SHEIKH Abdulrehman A ALATAR Department of Botany & Microbiology College of Science King Saud University Riyadh 11451 Saudi Arabia Botany Department Faculty of Science Damanhour University Damanhour 22516 Egypt

Shada Mountains in Saudi Arabia, separated by Maleel Wadi into twin mountains（i.e., Shada Alalah and Shada Asfal）, are rich in biodiversity. We investigated the diversity of endemics and endangered species of the mountains based on the data collected from 38 stands falling in 8 elevational zones ranging from 500 to 2215 m a.s.l. Results indicated that 495 plant species falling in 314 genera and 76 families occurred in the Shada Mountains, including 19 endemic species and 43 endangered species, and accounting for 22% of the total flora in Saudi Arabia. Canonical correlation analysis indicated that physiographic features, particularly altitude play an important role in the frequency and abundance of species. Endemics were not evenly distributed in the Shada Mountains and mostly restricted in the elevation zone of 1000–1500 or ＆gt;1500 m a.s.l. When the altitude reached up to 2000 m a.s.l., the endemics decreased substantially due to the significantly low temperature. The endangered species existed three different distribution patterns：（i） most endangered species distributed in the altitudes of 1000–1800 m a.s.l.;（ii） endangered trees, lianas, and shrubs occupied the altitudes 1000–1300 m a.s.l.; and（iii） endangered subshrubs and herbs inhabited the altitudes 1500–2100 m a.s.l. The results demonstrated that the biodiversity of endangered species in the Shada Mountains is high and undisturbed by invasive species, and protective measures should be taken against human disturbances to the small-scale hotspot.

关键词： elevational gradient invasion Shada Alalah Shada Asfal Wadi Jof