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HALOMETHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOLYTIC PATHWAY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： Sad Moulay nadia Mehdi Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

Image Encryption Algorithm Based on New Fractional Beta Chaotic Maps

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Computer Modeling in Engineering & Sciences 2022年第7期132卷 119-131页

作者： Rabha W.Ibrahim Hayder Natiq Ahmed Alkhayyat Alaa Kadhim Farhan nadia M.G.Al-Saidi Dumitru Baleanu Institute of Electrical and Electronics Engineers Kuala Lumpur59200Malaysia Information Technology College Imam Ja’afar Al-Sadiq UniversityBaghdad10001Iraq Department of Computer Technical Engineering College of Technical EngineeringIslamic UniversityNajaf192122Iraq Department of Computer Sciences University of TechnologyBaghdad10066Iraq Department of Applied Sciences University of TechnologyBaghdad10066Iraq Department of Mathematics Cankaya UniversityBalgatAnkara06530Turkey Institute of Space Sciences Magurele-BucharestR76900Romania Department of Medical Research China Medical UniversityTaichung40402Taiwan

In this study,a new algorithm of fractional beta chaotic maps is proposed to generate chaotic sequences for image *** proposed technique generates multi random sequences by shuffling the image pixel *** technique is used to blur the pixels connecting the input and encrypted images and to increase the attack *** proposed algorithm makes the encryption process sophisticated by using fractional chaotic maps,which hold the properties of *** fractional beta sequences are utilized to alter the image pixels to decryption *** experimental results proved that the proposed image encryption algorithm successfully encrypted and decrypted the images with the same *** output findings indicate that our proposed algorithm has good entropy and low correlation *** translates to enhanced security against different attacks.A MATLAB programming tool was used to implement and assess the image quality measures.A comparison with other image encryption techniques regarding the visual inspection and signal-to-noise ratio is provided.

关键词： Fractional calculus fractional beta function chaotic function image encryption

Cybersecurity Requirements for Management Information Systems

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Journal of Information Security 2023年第3期14卷 212-226页

作者： nadia K. Samara Business Administration Department Arab Open University Amman Jordan

Cybersecurity is therefore one of the most important elements of security in developed countries. Especially since there is an overall trend towards cybersecurity in all aspects of life, I have found that the idea of cybersecurity is based on protecting critical facilities: The nation’s information infrastructure. Information systems, including e-government management systems, are managed by key state agencies. As with economic, scientific, commercial, and other systems, threats are threats to a nation’s national security. We have therefore found that many countries are preparing institutions capable of integrating cybersecurity into protection, development, and information security. This concept has become the most important concern of developed countries, which have secured all scientific possibilities and systems to achieve it. The electronic information network has become an integral part of today’s daily lives in all places. In addition to personal uses, digital information is used, processed, stored, and shared. As this information increases and spreads, we have found that its protection has become more vital and has an effective impact on national security and technical progress.

关键词： Cybersecurity Security Information Systems

Preservation of Juniperus thurifera L.:a rare endangered species in Algeria through in vitro regeneration

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Journal of Forestry Research 2019年第1期30卷 77-86页

作者： nadia Khater Halima Benbouza Faculté SNV Université Batna 2 Institut des Sciences Vétérinaires et Sciences Agronomiques Université Batna 1 Centre de Recherche en Biotechnologies

Juniperus thurifera *** an endemic Cupres saceae from the Aure`s Mountains of north eastern Algeria and endangered,in part,due to the scarcity of viable seeds It is threatened by other abiotic factors and the lack of an effective management strategy will increase its risk o *** dearth of information on its in vitro regeneration impedes its application in forest managemen *** therefore developed a micropropagation protocol using microcuttings with auxiliary *** were grown on different combinations of media supplemented with plant growth regulators at different *** highest number of shoots and branches regenerated from original shoots was obtained on Woody Plant Medium(WPM)supplemented with 6-benzylaminopurine(BAP)(0.5 mg L^(-1))and 2,4-dichlorophe noxyacetic acid(2,4-D)(0.25 mg L^(-1)).The best elongation of shoots was achieved with WPM supplemented with0.5 mg L^(-1)of BAP and 0.25 or 1 mg L^(-1) of 2,*** the second subculture,shoots had a higher number of branches than those of the *** highest rooting rate,38.8%,was obtained with shoots cultured in 1/2 Murashige and Skoog(MS)medium supplemented with 5.0 mg L^(-1)each of indol-3-butyric(IBA)and naphthalene acetic acid(NAA).Similarly,the highest root numbers and lengths were produced on 1/2 MS medium supplemented with IBA and NAA(5.0 mg L^(-1)each).During transfer to acclimatization,rates of plant losses of 50% *** second part of the experiment showed that the best shoot callusing was on WPM supplemented with BAP and 2,4-D,with either the combination 0.5+0.25 or 0.25+0.25 mg L^(-1).The results of this research provide a starting point for further studies on in vitro regeneration of *** for the sustainable management of its unique ecosystem in the Mediterranean basin.

关键词： Juniperus thurifera Callus Conservation Regeneration In vitro culture

The relation between a microscopic threshold-force model and macroscopic models of adhesion

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Acta Mechanica Sinica 2017年第3期33卷 508-515页

作者： Srivatsan Hulikal Kaushik Bhattacharya nadia Lapusta School of Engineering Brown University Department of Mechanical and Civil Engineering California Institute of Technology

This paper continues our recent work on the relationship between discrete contact interactions at the microscopic scale and continuum contact interactions at the macroscopic scale (Hulikal et al., J. Mech. Phys. Solids 76, 144-161, 2015). The focus of this work is on adhesion. We show that a collection of a large number of discrete elements governed by a threshold-force based model at the microscopic scale collectively gives rise to continuum fracture mechanics at the macroscopic scale. A key step is the introduction of an efficient numerical method that enables the computation of a large number of discrete contacts. Finally, while this work focuses on scaling laws, the methodology introduced in this paper can also be used to study rough-surface adhesion.

关键词： Adhesion Threshold-force model Johnson-Kendall-Roberts (JKR) theory Fracture Fast Multipole Method

Epidemiology of Pemphigus: A Single Center Experience in Morocco

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International Journal of Dermatology and Venereology 2022年第1期5卷 20-26页

作者： Farah El Hadadi Line Mezni Karima Senouci Laila Benzekri nadia Ismaili Mariame Meziane Department of Dermatology-Venereology Ibn Sina University HospitalMohammed V UniversityRabat 10100Morocco

Objective:Pemphigus is a life threatening autoimmune bullous disease which involves the skin and mucous membranes of the stratified squamous *** global distribution of Pemphigus varies according to genetic,ethnic,socioeconomic,and cultural *** purpose of our study is to evaluate the epidemiological features of pemphigus a single center in Morocco and compare our results with those reported ***:A retrospective analysis was conducted of 302 pemphigus patients seen between 1990 and 2020 in the Dermatology Department of Ibn Sina Hospital(Rabat,Morocco).We further collected all the Moroccan scientific researches published by now to ***:The average annual incidence was 0.32/100,000 *** incidence doubled to 0.72 in *** most common variant was pemphigus vulgaris(125 cases)followed by pemphigus erythematosus(99 cases),pemphigus foliaceous(40 cases),and vegetans(27 cases).The female to male ratio was 0.75,the average age at onset was 53 years old and the mean duration of the disease before diagnosis was ***:This study joins the main characteristics of pemphigus in the Maghreb and around the world(pemphigus vulgaris most frequent subtype).In 2020,an epidemiological peak occurred during the coronavirus disease 2019 pandemic;probably related to stress and delayed time consultation for fear of contracting the severe acute respiratory syndrome coronavirus 2.

关键词： pemphigus epidemiology Rabat Morocco autoimmune bullous disease desmoglein

Does antecolic reconstruction decrease delayed gastric emptying after pancreatoduodenectomy?

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World Journal of Gastroenterology 2012年第45期18卷 6527-6531页

作者： nadia Peparini Piero Chirletti Azienda Sanitaria Locale Roma H 00043 RomeItaly Department of Surgical Sciences Sapienza University of Rome00161 RomeItaly

Delayed gastric emptying(DGE) is a frequent complication after pylorus-preserving pancreatoduodenectomy(PpPD).Kawai and colleagues proposed pylorus-resecting pancreatoduodenectomy(PrPD) with antecolic gastrojejunal anastomosis to obviate DGE occurring after *** we debate the reported differences in the prevalence of DGE in antecolic and retrocolic gastro/duodeno-jejunostomies after PrPD and PpPD,*** concluded that the route of the gastro/duodeno-jejunal anastomosis with respect to the transverse colon;i.e.,antecolic route or retrocolic route,is not responsible for the differences in prevalence of DGE after pancreatoduodenectomy(PD) and that the impact of the reconstructive method on DGE is related mostly to the angulation or torsion of the gastro/*** report a prevalence of 8.9% grade A DGE and 1.1% grade C DGE in a series of 89 subtotal stomach-preserving PDs with Roux-en Y retrocolic reconstruction with anastomosis of the isolated Roux limb to the stomach and single Roux limb to both the pancreatic stump and hepatic *** anastomosis of the isolated first jejunal loop to the gastric remnant allows outflow of the gastric contents by gravity through a "straight route".

关键词：十二指肠胃排空切除术延迟肠吻合术 DGE 患病率胃内容物

Instrumented assisted soft tissue mobilization vs extracorporeal shock wave therapy in treatment of myofascial pain syndrome

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World Journal of Orthopedics 2023年第7期14卷 572-581页

作者： Nourhan Elsayed Shamseldeen Mohammed Moustafa Aldosouki Hegazy nadia Abdalazeem Fayaz Nesreen Fawzy Mahmoud Department of Physical Therapy for Musculoskeletal Disorders&Its Surgery Faculty of Physical TherapyCairo UniversityCairo 14531Egypt

BACKGROUND Active myofascial trigger points(TrPs)often occur in the upper region of the upper trapezius(UT)*** TrPs can be a significant source of neck,shoulder,and upper back pain and *** TrPs and their related pain and disability can adversely affect an individual’s everyday routine functioning,work-related productivity,and general quality of *** To investigate the effects of instrument assisted soft tissue mobilization(IASTM)vs extracorporeal shock wave therapy(ESWT)on the TrPs of the UT *** A randomized,single-blind,comparative clinical study was conducted at the Medical Center of the Egyptian Railway Station in *** patients(28 females and 12 males),aged between 20-years-old and 40-years-old,with active myofascial TrPs in the UT muscle were randomly assigned to two equal groups(A and B).Group A received IASTM,while group B received *** group was treated twice weekly for 2 *** groups received muscle energy technique for the UT *** were evaluated twice(pre-and posttreatment)for pain intensity using the visual analogue scale and for pain pressure threshold(PPT)using a pressure *** Comparing the pre-and post-treatment mean values for all variables for group A,there were significant differences in pain intensity for TrP1 and TrP2(P=0.0001)and PPT for TrP1(P=0.0002)and TrP2(P=0.0001).Also,for group B,there were significant differences between the pre-and post-treatment pain intensity for TrP1 and TrP2 and PPT for TrP1 and TrP2(P=0.0001).There were no significant differences between the two groups in the post-treatment mean values of pain intensity for TrP1(P=0.9)and TrP2(P=0.76)and PPT for TrP1(P=0.09)and for TrP2(P=0.91).CONCLUSION IASTM and ESWT are effective methods for improving pain and PPT in patients with UT muscle *** is no significant difference between either treatment method.

关键词： Myofascial trigger points Upper trapezius muscle Instrument-assisted soft tissue mobilization Extracorporeal shock wave therapy Myofascial pain syndrome

A test of the coupling of predator defense morphology and behavior variation in two threespine stickleback populations

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Current Zoology 2012年第1期58卷 53-65页

作者： Lacasse, Jennyfer Aubin-Horth, nadia Département de Biologie & Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval. Québec QC Canada. G1V 0A6

Among-population differences in morphology and behaviors such as boldness have been shown to co-vary with ecological conditions, including predation regime. However, between- and within-population covariation of predator defense morphology with variation in behaviors relevant to ecology and evolution (boldness, exploration, activity, sociability and aggressiveness, often defined as personality traits when they are consistent across time and contexts) have never been quantified together in a single study in juvenile fish from populations found in contrasting environments. We measured predator defense morphology differences between adults from two freshwater populations of threespine sticklebacks with different ecological conditions. We then quantified five behaviors in juveniles from both populations raised in a common environment. Wild-caught adults showed significant differences in predator defense morphology. One population had significantly lower lateral plate number, shorter dorsal spine, pelvic spine and pelvic girdle. Furthermore, 61% of individuals from that population showed an absence of pelvic spine and girdle. At the population level, we found that differences in defense morphology in adults between the two lakes were coupled with differences in behaviors in juveniles raised in a common environment. Levels of activity, aggressiveness and boldness were higher in juveniles from the population lacking predator defense structures. At the individual level, anti-predator morphology of adult females could not predict their offspring’s behavior, but juvenile coloration predicted individual boldness in a population-specific manner. Our results suggest that ecological conditions, as reflected in adult predator defense morphology, also affect juvenile behavior in threespine sticklebacks, resulting in trait co-specialization, and that there is a genetic or epigenetic component to these behavioral differences.

关键词：形态差异人的行为防御结构捕食者耦合试验种群生态条件成年人