Israeli nuclear deterrence: the failure of a concept: how did the change in Israel\u27s strategic context affect the usefulness of the Israeli nuclear deterrent?

This study will aim at examining how the changes in Israelâ s security environment affected the strategic usefulness of its nuclear deterrent. The Israeli nuclear deterrent was developed during the 1950s and the 1960s when Israelâ s strategic setting was, mainly, dominated by state-centered security threats. Consequently, Israel, at the time, was mainly concerned with the possible symmetrical military confrontations with its Arab neighbors; something that would have created strategic value for the Israeli nuclear deterrent. Yet, a closer examination of the evolution of the Israeli security environment since 1982 will reveal that Non-State Actors (NSAs) and asymmetrical forms of warfare, slowly but surely, have dominated the Israeli security setting. The year 1982 is chosen because it is the date of the last major military confrontation between Israel and another state (Syria in that case) in a symmetrical form of warfare. Since then, Israelâ s major security threats originated from NSAs either operating from neighboring states (as in the case of Hezbollah in Lebanon) and/or Palestinian groups operating in Israel or from the occupied Arab territories in the West Bank and the Gaza Strip. The most obvious example of this new type of threats is the highly successful campaign launched by Hezbollah, throughout the 1980s and 1990s, against the Israeli occupation of Southern Lebanon, which eventually led to an Israeli withdrawal in 2000. In this campaign Hezbollah depended on asymmetrical forms of warfare that left the Israeli Defense Forces (IDF) entangled in a long and destructive war of attrition. In addition to Hezbollah, both the first and the second Intifadas proved to be a great security threat to Israel, as the Palestinians, generally and more so in the second Intifada, devised and restored to asymmetrical means of warfare that proved hard to break using conventional military means. This rise of threats stemming mainly of NSAs and asymmetrical means of warfare was coupled with the simultaneous and relative decline of state-centered security threats; which are threats mainly originating from states mounting regular and symmetrical wars. In fact, this relative decline of state-centered security threats initiated by a complex set of, often interrelated, political and strategic factors. This study will aim, first, at providing a comprehensive overview of how and which context did Israel develop its nuclear deterrent and how was it related to the Israeli self-perception and strategy of deterrence. Second, the study will tackle the changes that took place in Israelâ s strategic setting over the past three decades; discussing, in the process, the various political and strategic factors that led to the decline of the state-centered security threats and the simultaneous rise of NSAs as Israelâ s main security threat. Finally, the effect of this change in Israelâ s threat map on the usefulness of Israeli nuclear deterrent will be examined

Determinants of the demand for microenterprise finance in urban Egypt

SIGLEAvailable from British Library Document Supply Centre- DSC:DXN059124 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Structural Performance of Polyester Resin Concrete

This work was carried out in an attempt to widen the potential use of polymer concrete in the construction industry. The concept of ultimate strength limit state in design of PC is furnished on the bases of the mechanical properties found experimentally. Five distinct PC grades of polyester resin concrete that might fairly represent average properties of PC were proportioned after studying the potential optimization techniques of resin mortar mix design for which a mix design chart is developed. Most of the mechanical properties of the five PC grades were investigated under short term conditions. The stress block shape and parameters of the compression zone in flexure are explored. Empirical and theoretical values for the stress block parameters are developed. These values were used in full scale structural applications, a beam and a column for each PC grade, and were found to be satisfactorily accurate. The concept of specific reinforcement ratio to be used with high tensile steel reinforcement which has no definite yield point is established. The effects of rate of loading and sustained load were studied. Expressions for long-term ultimate compressive strength, long-term modulus of elasticity, sustained strength, macrocracking strain and creep strains are given for various PC grades. Ultimate strength design procedures and their design charts for various loading conditions and relevant values of capacity reduction factors are suggested on the basis of the structural performance of PC under short-term and long-term conditions

Terminal complement complex C5b-9 and C5b assay in sera of COVID-19 patients with different disease severities

Objective: The aim of this study is to find out the link between the involvement of complement activation in the inflammatory reactions in COVID-19 patients, the deterioration of the clinical status and development of sever COVID-19 in those patients. Methodology: The study included 274 COVID-19 patients, divided into three groups; group1: severe COVID-19 patients (n=37), group 2; moderate COVID-19 severity patients (n=78), group 3; mild COVID-19 severity patients (n=159). Serum levels of C-reactive protein, D-dimer, and ferritin were measured in the three patient groups, and the patients were subjected to CT chest imaging.  Serum levels of the tested biomarkers were measured by ELISA at diagnosis. Results: Sever COVID-19 patients had higher serum levels of ferritin and D-dimer in comparison to patients with moderate and mild severity COVID-19 with statistically significant difference (p < /em> value 0.01 and 0.02 respectively). There was a significant elevation in the serum levels IL-6 and TNF-α in severe COVID-19 patients (488.5±112.2 and 159.6±38.3 respectively) versus moderate (206.07±53.3 and 93.5±39.5) and mild group (200.9± 52.27 and 52.9±23) respectively, (p < /em> value < 0.001). There was also a significant elevation of C5b and C5b-9 serum levels in severe COVID-19 patients (18.6±10.3 and 73.25±7.35) compared to moderate (14.11±15.6 and 143.6±170) and mild COVID-19 groups (76± 11.32 and 3.9± 3.03) respectively. Conclusion: We conclude that the severity of inflammation presented in elevated neutrophil counts and serum levels of inflammatory cytokines IL-6 and TNF in association with sever complement activation are implicated in severity and bad prognosis of COVID-19

CO₂ Foam for Enhanced Oil Recovery Applications

CO2-foam yields improved sweep efficiency in enhanced oil recovery (EOR) applications over that of polymers to avoid potential polymer-induced formation damage. In addition to carbon sequestration in underground formations, CO2 foam has low water content, which also reduces formation damage in water-sensitive formations and allows for fast cleanup. However, foam stability diminishes in harsh environments such as those with high salinity and temperature and when in contact with crude oil. This chapter highlights the different foam-generation mechanisms and the deterioration effect of crude oil on CO2-foam stability. More specifically, this chapter investigates using nanoparticles and viscosifiers to improve foam stability. Further, the effects of different nanoparticles, including aluminum oxide, copper oxide, and low-cost nanoparticles such as silicon dioxide, will be demonstrated. Field applications of viscoelastic surfactants and polymers in foam systems are also reviewed. The controlling factor for these different systems is the foam stability and improved oil recovery

Removing Ilmenite-Based Filter Cakes Using Hydrochloric Acid and Chelating Agent – Experimental Study

Ilmenite is often used as a weighting agent in drilling fluids to increase the fluid density, but the formation of a filter cake on the borehole wall can impact cementing operations and reduce well productivity. To remove the filter cake, various techniques can be employed such as chemical treatments, mechanical methods, or a combination of both. The goal of this study is to evaluate the effectiveness of chemical removal of ilmenite-based filter cake using 7.5 wt.% hydrochloric acid (HCl) and hydroxyethyl ethylenediamine triacetic acid (HEDTA) – chelating agent. The filter cakes were generated using API filter press under harsh conditions of 300 psi pressure and 250°F temperature. Sandstone cores (2.5-in. diameter and 1-in. thickness) were utilized to replicate the formation during filtration experiments. The filtrate fluid was collected and the sandstone cores with filter cakes were scanned using computerized tomography (CT) technology. Immediately after that, the cores and filter cakes were soaked with HCl–HEDTA solution for 6 hours, followed by CT-scanning the cores and remaining filter cakes again. After acidizing, the effluent solution was analyzed using inductively coupled plasma (ICP). Scanning electron microscopy–energy dispersive spectroscopy (SEM-EDS) was used to analyze the dried filter cakes and remaining residue. The results showed that, the use of 7.5 wt.% HCl was effective in partially removing the ilmenite-based filter cake. Additionally, the use of HEDTA showed limited effect on the efficiency of filter cake removal, but it effectively prevented corrosion problems during the treatment. This study presents useful findings on removing ilmenite-based filter cake with a low acid concentration and reducing the risk of corrosion issues

Thermomechanical treatment of austempered ductile iron

The production of lightweight ferrous castings with increased strength properties became unavoidable facing the serious challenge of lighter aluminum and magnesium castings. The relatively new ferrous casting alloy ADI offers promising strength prospects, and the thermo-mechanical treatment of ductile iron may suggest a new route for production of thin-wall products. This work aims at studying the influence of thermomechanical treatment, either by ausforming just after quenching and before the onset of austempering reaction or by cold rolling after austempering. In the first part of this work, ausforming of ADI up to 25% reduction in height during a rolling operation was found to add a mechanical processing component compared to the conventional ADI heat treatment, thus increasing the rate of ausferrite formation and leading to a much finer and more homogeneous ausferrite product. The kinetics of ausferrite formation was studied using both metallographic as well as XRD-techniques. The effect of ausforming on the strength was quite dramatic (up to 70% and 50% increase in the yield and ultimate strength respectively). A mechanism involving both a refined microstructural scale and an elevated dislocation density was suggested. Nickel is added to ADI to increase hardenability of thick section castings, while ausforming to higher degrees of deformation is necessary to alleviate the deleterious effect of alloy segregation on ductility. In the second part of this work, the influence of cold rolling (CR) on the mechanical properties and structural characteristics of ADI was investigated. The variation in properties was related to the amount of retained austenite (γr) and its mechanically induced ransformation. In the course of tensile deformation of ADI, transformation induced plasticity (TRIP) takes place, indicated by the increase of the instantaneous value of strain-hardening exponent with tensile strain. The amount of retained austenite was found to decrease due to partial transformation of γr to martensite under the CR strain. Such strain-induced transformation resulted in higher amounts of mechanically generated martensite. The strength and hardness properties were therefore increased, while ductility and impact toughness decreased with increasing CR reduction

تحليل فكرة النظم عند الإمام عبد القاهر الجرجاني = The analysis the idea of al-nizm for al-imam 'Abdal Qahir Al-Jurjani

تناقش هذه المقالة تحليل فكرة النظم عند الإمام عبد القاهر الجرجاني،وخلاصة المقال، أن الإمام عبد القاهر في فكرته عن تحليل النصوص اعتمد على كشف مواضع اللفظة في السياق، وما تحمله هذه اللفظة من صور ومشاعر ومعان تتأجج وتتولد من نتاج الترابط والتعالق بأخواتها في السياق الذي هي فيه، أي أن النظم هو السبيل في تفسير فصاحة القول وبيانه، وبيان سرّ البلاغة والفصاحة والبيان في قول الناظم، وهذا ما سوف يكشف عنه البح

كتب طبقات الشعراء وقضايا النقد الأدبي (Kutub tabaqat al-shu'ara' wa-qadaya al-naqd al-adabi)

يعالج هذا الكتاب قضايا النقد الأدبي القديم في ضوء كتب طبقات الشعراء، وذلك من حلال العصور القديمة، منذ العصر الجاهلي إلى العصر العباسي. ويتناول قضايا شتى في هذه المسألة؛ مثل: أثر البيئة في الأدب، وقضية الطبع والتكلف في الشعر العربي، وقضية السرقات الأدبية، وقضية اللفظ والمعنى، وقضية الحكومات الأدبية، وقضية الناقد زمقاييسه الأدبية، وذلك من خلال النقد والتحلي