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Effect of fluence and ambient environment on the surface and structural modification of femtosecond laser irradiated Ti

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Chinese Physics B 2016年第1期25卷 789-795页

作者： Umm-i-Kalsoom Shazia Bashir Nisar Ali M Shahid Rafique Wolfgang Husinsky Chandra S R Nathala Sergey V Makarov narjis Begum Institute for Applied Physics Vienna University of TechnologyViennaAustria Centre for Advanced Studies in Physics GC University LahorePakistan Department of Physics The University of LahorePala'stan Department of Basic Sciences and Humanities University of Engineering and Technology FasalabadPakistan Department of Physics University of Engineering and Technology LahorePakistan P.N.Lebedev Physics Institute RAS MoscowRussia Department of Physics COMSATS Institute of Information and TechnologyIslamabadPakistan

Under certain conditions, ultrafast pulsed laser interaction with matter leads to the formation of self-organized conical as well as periodic surface structures （commonly reffered to as, laser induced periodic surface structures, LIPSS）. The purpose of the present investigations is to explore the effect of fsec laser fluence and ambient environments （Vacuum ＆ 02） on the formation of LIPSS and conical structures on the Ti surface. The surface morphology was investigated by scanning electron microscope （SEM）. The ablation threshold with single and multiple （N = 100） shots and the existence of an incubation effect was demonstrated by SEM investigations for both the vacuum and the 02 environment. The phase analysis and chemical composition of the exposed targets were performed by x-ray diffraction （XRD） and energy dispersive x-ray spectroscopy （EDS）, respectively. SEM investigations reveal the formation of LIPSS （nano ＆ micro）. FFT d-spacing calculations illustrate the dependence of periodicity on the fluence and ambient environment. The periodicity of nano-scale LIPSS is higher in the case of irradiation under vacuum conditions as compared to 02. Furthermore, the 02 environment reduces the ablation threshold. XRD data reveal that for the 02 environment, new phases （oxides of Ti） are formed. EDS analysis exhibits that after irradiation under vacuum conditions, the percentage of impurity element （A1） is reduced. The irradiation in the 02 environment results in 15% atomic diffusion of oxygen.

关键词： LIPSS ablation threshold incubation coefficient structural modification

Femtosecond laser induced nanostructuring of zirconium in liquid confined environment

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Chinese Physics B 2017年第1期26卷 310-319页

作者： Nisar Ali Shazia Bashir Umm-i-Kalsoom M.Shahid Rafique narjis Begum Wolfgang Husinsky Ali Ajami Chandra S.R.Natahala Laser Laboratories Institute for Applied Physics Vienna University of Technology 1040 Vienna Austria Department of Basic Sciences and Humanities University of Engineering and Technology Lahore Faisalabad Campus Faisalabad Pakistan Laser Laboratories Centre for Advanced Studies m Physics GC University 1-Church Road Lahore Pakistan Department of Physics GC University Kachehri Road Lahore Pakistan Department of Physics Riphah International University Islamahad (Lahore Campus) Lahore Pakistan Department of Physics University of Engineering and Technology Lahore Pakistan Department of Physics COMSATS Institute of Information Technology Islamabad Pakistan

The surface, structural, and mechanical properties of zirconium after irradiation with Ti： sapphire laser（800 nm, 30 fs,1 k Hz） have been investigated. The zirconium targets were exposed for a varying number of laser pulses ranging from 500 to 2000 at a fixed fluence of 3.6 J/cm^2 corresponding to an intensity of 1.2×10^14W/cm^2 in ambient environments of deionized water and propanol. A scanning electron microscope（SEM） was employed to investigate the surface morphology of the irradiated zirconium. The SEM analysis shows the formation of various kinds of features including nanoscale laser induced periodic surface structures（LIPSS）, sponge like surface structure, flakes, conical structures, droplets, pores, and cavities. The energy dispersive x-ray spectroscopy（EDS） analysis exhibits the variation in chemical composition along with an enhanced diffusion of oxygen under both ambient conditions. The crystal structure and phase analyses of the exposed targets were explored by x-ray diffraction（XRD） and Raman spectroscopy techniques, respectively. The XRD analysis confirms the presence of various phases of zirconium hydride and zirconia after ablation in both de-ionized water and propanol. However, excessive hydrides are formed in the case of propanol. The Raman analysis supports the EDS and XRD results. It also reveals the presence of oxides（zirconia） after irradiation in both de-ionized water and propanol *** chemical reactivity of zirconium was significantly improved in the presence of liquids which were accountable for the growth of novel phases and modification in the chemical composition of the irradiated Zr. A nanohardness tester was employed to measure the nanohardness of the laser treated targets. The initial increase and then decrease in nanohardness was observed with an increase in the number of laser pulses in the de-ionized water environment. In the case of propanol,a continuous decrease in hardness was observed.

关键词： ambient environments periodic structure crystallinity synthesis

Therapeutic approaches and drug-resistance in chronic lymphocytic leukaemia

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Cancer Drug Resistance 2020年第3期3卷 532-549页

作者： narjis Fatima Kyle R.Crassini Lauren Thurgood Yandong Shen Richard I.Christopherson Bryone Kuss Stephen P.Mulligan Oliver Giles Best Kolling Institute of Medical Research University of SydneyRoyal North Shore HospitalSydneyNSW 2065Australia. School of Life and Environmental Sciences University of SydneySydney NSW 2008Australia. College of Medicine and Public Health Flinders UniversityBedford ParkAdelaideSA 5042Australia.

The treatment of chronic lymphocytic leukaemia has been revolutionised in recent years,first by the introduction of chemoimmunotherapy regimens and subsequently by the development of drugs,including ibrutinib,idelalisib and venetoclax,that target components of the B-cell receptor signalling pathway or B-cell lymphoma 2 family of *** high initial response rates in patients treated with chemoimmunotherapy or targeted agents,a significant proportion of patients relapse with progressive and refractory *** a subset of these patients,drug resistance has been associated with specific genetic lesions or activation of alternate pro-survival ***,the mechanisms that confer drug resistance in the remainder of the patients with refractory disease have yet to be fully *** this review,we discuss our current understanding of the mechanics of drug resistance in chronic lymphocytic leukaemia and describe how this knowledge may aid in rationalising future treatment strategies to prevent the development of refractory or aggressive transformation of the disease.

关键词： Chronic lymphocytic leukaemia drug resistance targeted cancer therapy

Positive Magnetoresistance in Hydrogenated Amorphous Alloys Silicon Nickel a-Si<sub>1-y</sub>Niy:H at Very Low Temperature with Magnetic Field

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Journal of Modern Physics 2012年第6期3卷 447-450页

作者： Abdelfattah narjis Abdelhamid El kaaouachi Jamal Hemine Abdelghani Sybous Lhoussine Limouny Said Dlimi Rachid Abdia Gerard Buskipski Laboratoire de Physique de la Matière Condensée Département de Physique Faculté des Sciences et Techniques de Mohammadia Mohammedia Morocco Laboratoire de Spectroscopie Hertzienne LSH Université de LilleI Villeneuve d’Ascq Cedex France Research Group ESNPS Physics Department Faculty of Sciences University Ibn Zohr Agadir Morocco

We present results of an experimental study of magnetoresistance phenomenon in an amorphous silicon-nickel alloys a-Si1-yNiy:H:H (where y = 0.23) on the insulating side of the metal-insulator transition (MIT) in presence of magnetic field up to 4.5 T and at very low temperature. The electrical resistivity is found to follow the Efros-Shklovskii Variable Range Hopping regime (ES VRH) with T -1/2. This behaviour indicates the existence of the Coulomb gap (CG) near the Fermi level.

关键词： Amorphous Silicon-Nickel Alloys a-Si1-yNiy:H Variable Range Hopping Conductivity Metal Insulator Transition Positive Magnetoresistance

Negative Magnetoresistance Behaviour and Variable Range Hopping Conduction in Insulating NbSi Amorphous Alloys at Very Low Temperature with aagnetic Field

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Journal of Modern Physics 2012年第7期3卷 521-528页

作者： Abdelghani Sybous Abdelhamid El Kaaouachi Jamal Hemine Abdelfattah narjis Lhoussine Limouny Said Dlimi Rachid Abdia Gerard Biskupski Laboratoire de Physique de la Matière Condensée Faculté des Sciences et Techniques de Mohammadia Département de Physique Mohammedia Morocco Laboratoire de Spectroscopie Hertzienne LSH Batiment P5 Université des Sciences et Technologies de LilleI 59 655 Villeneuve d’Ascq Cedex France Research Group in ESNPS Physics Department University Ibn Zohr Faculty of Sciences B.P 8106 Hay Dakhla Agadir Morocco

We present results of an experimental study of magnetoresistance (MR) in insulating NbSi amorphous alloys sample showing Variable Range Hopping (VRH) conductivity. The MR is found to be negative in a wide range of low temperature (4.2-20 K) and in the range of moderate magnetic fields (0-4 T). We made tentative analysis using three theoretical models which are the model of quantum interference, the model of Zeeman effect and the model of localized magnetic

关键词： NbSi Amorphous Alloys Negative Magnetoresistance Magnetic Field Localized Magnetic moments Quantum Interference

Descriptive assessment on diabetic retinopathy screening in an awareness programme in Malaysia

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1808-1813页

作者： Nor Fariza Ngah Nor Asiah Muhamad Zalifa Zakiah Asnir Roslin Azni Abdul Aziz Zaidah Mhad Kassim Siti Aishah Sahar Nor Azita Ahmad Tarmidzi Chan Li Yen Rosmawati Uthman narjis Satar Noor Zahirah Husain Azian Adnan John Mathen Kayalakakathu Bariyah Kadas Noor Suriani Mohamad Shaiful Azlan Kassirn Department of Ophthalmology Shah Alam HospitalSelangor 40000Malaysia Sector for Evidence Based Healthcare National Institutes of HealthMinistry of HealthSelangor 40170Malaysia Institute for Public Health National Institutes of HealthMinistry of HealthSelangor 40170Malaysia Department of Ophthalmology Ampang HospitalSelangor 68000Malaysia Department of Ophthalmology Serdang HospitalSelangor 43000Malaysia Department of Ophthalmology Putrajaya HospitalFederal Territory 62250Malaysia Department of Ophthalmology Kuala Lumpur HospitalFederal Territory 50586Malaysia Department of Ophthalmology Tengku Ampuan Rahimah HospitalSelangor 41200Malaysia Department of Ophthalmology Selayang HospitalSelangor 68100Malaysia Department of Ophthalmology Sungai Buloh HospitalSelangor 47000Malaysia Selangor State Health Department Ministry of HealthSelangor 40100Malaysia

AIM:To determine the prevalence of diabetic retinopathy(DR)among diabetic patients at the primary health clinics in Selangor,***:All diabetic patients were screened in Retinal Disease Awareness Programme(RDAP)and those who had significant DR changes were referred to the hospital for further *** analyses were done to determine the prevalence of DR and sociodemographic characteristics among patients with *** and multivariable analysis using Logistic regression were performed to find association and predictor factors in this ***:A total of 3305 patients aged 40y and above were screened for *** patients screened,9%patients were found to have DR and other visual complication such as maculopathy(0.9%),cataract(4.8%)and glaucoma(0.4%).The mean age of patients without retinopathy was 57.82±8.470y and the mean age of patients with DR was 63.93±*** 61.5%of the patients screened were aged below 60y and 38.5%were aged 60y and *** of the patients screened were women 58.5%and Malay in the age group of 50-59y,while 27%were aged *** association were found between age,sex,race,visual loss and ***:Although the prevalence of DR among patients is not alarming,effective interventions need to be implemented soon to avert a large burden of visual loss from DR.

关键词： diabetic retinopathy retinal disease awareness programme eye screening Selangor

Variable Range Hopping in Hydrogenated Amorphous Silicon-Nickel Alloys

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Journal of Modern Physics 2012年第7期3卷 517-520页

作者： Abdelfattah narjis Abdelhamid El kaaouachi Abdelghani Sybous Lhoussine Limouny Said Dlimi Abdessadek Aboudihab Jamal Hemine Rachid Abdia Gerard Biskupski Laboratoire de Physique de la Matière Condensée Faculté des Sciences et Techniques de Mohammadia Département de Physique Mohammedia Morocco Laboratoire de Spectroscopie Hertzienne LSH Batiment P5 Université des Sciences et Technologies de LilleI 59 655 Villeneuve d’Ascq Cedex France Research Group ESNPS Physics Department University Ibn Zohr Faculty of Sciences B.P 8106 Hay Dakhla 80000 Agadir Morocco

On the insulating side of the metal-insulator transition (MIT), the study of the effect of low Temperatures T on the electrical transport in amorphous silicon-nickel alloys a-Si1-yNiy:H exhibits that the electrical conductivity follows, at the beginning, the Efros-Shklovskii Variable Range Hopping regime (ES VRH) with T-1/2. This behaviour showed that long range electron-electron interaction reduces the Density Of State of carriers (DOS) at the Fermi level and creates the Coulomb gap (CG). For T higher than a critical value of temperature TC, we obtained the Mott Variable Range Hopping regime with T-1/4, indicating that the DOS becomes almost constant in the vicinity of the Fermi level. The critical temperature TC decreases with nickel content in the alloys.

关键词： Amorphous Silicon-Nickel Alloys a-Si1-yNiy:H Variable Range Hopping Conductivity Transport Phenomenon Metal Insulator Transition

Atherosclerotic cardiovascular disease among patients with type 2 diabetes in Basrah

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World Journal of Diabetes 2013年第3期4卷 82-87页

作者： Abbas Ali Mansour narjis AH Ajeel Division of Endocrine and Metabolism Basrah College of MedicineBasrah 61013Iraq Department of Community Medicine Basrah College of MedicineBasrah 61013Iraq

AIM:To determine the frequency of atherosclerotic cardiovascular disease and its risk factors among patients with type 2 diabetes in Basrah,***:Participants in this cross-sectional study were patients who had type 2 diabetes for at least 1 year,presenting at the Al-Faiha Diabetes Endocrine and Metabolism Center in Basrah(Southern Iraq) over the period from January to December ***:The series included 1079 patients(58.8% men),of whom 25.0% were *** prevalence of symptomatic cardiovascular disease and hypertension was 16.0%,and 44.3% *** who were overweight or obese constituted 70.5%.Insulin was used in only 26.9% despite 56.1% having had diabetes for 6 years and *** mean glycated hemoglobin(HbA1c) was 9.46% ± 2.0% and only 5.5% achieved the target of HbA1c of < 7%.We had 68.7% of patients with total cholesterol of ≥ 200 mg/dL,21.5% with high density lipoprotein cholesterol of < 40 mg/dL,84.1% with low density lipoprotein cholesterol of ≥ 100 mg/dL and 71.6% with triglyceride of ≥ 150 mg/***:Among adults with type 2 diabetes mellitus,there was increased frequency of cardiovascular disease and its modifiable risk *** finding necessitated urgent work to modify these risk factors in a population based setting.

关键词： Cardiovascular risk factors Diabetes mellitus Type 2 diabetes mellitus Cardiovascular disease

Terrorist attacks in the largest metropolitan city of Pakistan: Profile of soft tissue and skeletal injuries from a single trauma center

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World Journal of Emergency Medicine 2015年第3期6卷 217-220页

作者： Muhammad Shahid Khan Shahan Waheed Arif Ali narjis Mumtaz Asher Feroze Shahryar Noordin Aga Khan University Hospital

BACKGROUND: Pakistan has been hugely struck with massive bomb explosions(car and suicide bombs) resulting in multiple casualties in the past few years. The aim of this study is to present the patterns of skeletal and soft tissue injuries and to review the outcome of the victims who presented to our ***: This is a retrospective chart review from January 2008 to December 2012. The medical record numbers of patients were obtained from the hospital Health Information and Management Sciences(HIMS) as per the ICD-9 ***: During the study period, more than 100 suicide and implanted bomb blast attacks took place in the public proceedings, government offices, residential areas and other places of the city. Altogether 262 patients were enrolled in the study. The mean age of the patients was 31±14 years. The shrapnel inflicted wounds were present on to the upper limb in 24 patients and the lower limb in ***: Long bone fractures were the most common skeletal injuries. The fractures were complicated by penetrating fragments and nails which result in post operative infections and prolonged hospital stay.

关键词： Soft tissue injuries Pakistan