Showing papers by "American University in Cairo published in 2006"
TL;DR: Nanodiagnostic assays promise increased sensitivity, multiplexing capabilities, and reduced cost for many diagnostic applications as well as intracellular imaging.
Abstract: Background: The use of nanotechnologies for diagnostic applications shows great promise to meet the rigorous demands of the clinical laboratory for sensitivity and cost-effectiveness. New nanodiagnostic tools include quantum dots (QDs), gold nanoparticles, and cantilevers. QDs, which are the most promising nanostructures for diagnostic applications, are semiconductor nanocrystals characterized by high photostability, single-wavelength excitation, and size-tunable emission. QDs and magnetic nanoparticles can be used for barcoding of specific analytes. Gold and magnetic nanoparticles are key components of the bio-barcode assay, which has been proposed as a future alternative to the PCR.
Methods: We examined articles published over the past 10 years investigating the use of QDs, gold nanoparticles, cantilevers, and other nanotechnologies in promising diagnostic applications.
Results: Several nanodiagnostic assays have been developed, including a QD-based assay capable of detecting biotinylated prostate-specific antigen (PSA) at 0.38 ng/L, a bio-barcode assay capable of detecting 30 amol/L PSA in a 10-μL sample, and another able to detect 50 molecules of the Alzheimer marker amyloid β-derived diffusible ligand in 10 μL of cerebrospinal fluid.
Conclusions: Nanodiagnostics promise increased sensitivity, multiplexing capabilities, and reduced cost for many diagnostic applications as well as intracellular imaging. Further work is needed to fully optimize these diagnostic nanotechnologies for clinical laboratory setting and to address the potential health and environmental risks related to QDs.
202 citations
TL;DR: A proposed model for a municipal solid waste management system in Port Said, Egypt is presented, which includes the use of the concept of collection stations, which have not yet been used in Egypt.
196 citations
TL;DR: The Arab language version of the Parental Authority Questionnaire (PAQ) was administered to 2,893 Arab adolescents in eight Arab societies and the results showed that all parenting styles differed across Arab societies as mentioned in this paper.
Abstract: The Arab language version of the Parental Authority Questionnaire was administered to 2,893 Arab adolescents in eight Arab societies. Results show that all parenting styles differed across Arab societies. Cluster analysis revealed three combined parenting patterns: inconsistent (permissive and authoritarian), controlling (authoritarian and authoritative), and flexible (authoritative and permissive). The mean score of the authoritarian style was higher among males, whereas the mean score of the authoritative style was higher among females. First-born adolescents reported higher level permissive parenting than other adolescents. The effects of urbanization, parents’ education, and the family economic level on parenting were minor.
183 citations
TL;DR: In this article, the Psychological State Scale, Multigenerational Scale, and the Parental Authority Questionnaire were administered to 2,893 Arab adolescents in eight Arab societies and the results indicated that inconsistent parenting was associated with higher level of connectedness with the family and better mental health of adolescents.
Abstract: The Psychological State Scale, Multigenerational Scale, and the Parental Authority Questionnaire were administered to 2,893 Arab adolescents in eight Arab societies. In these tests, adolescents raised according to the inconsistent parenting scored lower in connectedness and higher in mental disorders than those raised according to the controlling or flexible-oriented parenting pattern. Authoritative parenting was associated with a higher level of connectedness with the family and better mental health of adolescents. A higher level of adolescent-family connectedness is associated with better mental health of adolescents. Results indicate that authoritarian parenting within an authoritarian culture does not harm the adolescents’ mental health as it does within the Western liberal societies. These results give rise to the hypothesis that inconsistency in parenting and inconsistency between the parenting style and the culture cause harm to adolescents’ mental health.
156 citations
TL;DR: FFA(u) may have a potential role in identifying patients with cardiac ischemia and H-FABP is useful for detecting cardiac injury in acute coronary syndromes and predicting recurrent cardiac events in acuteocardial syndrome and in congestive heart failure patients.
Abstract: Background: A biomarker that reliably detects myocardial ischemia in the absence of necrosis would be useful for initial identification of unstable angina patients and for differentiating patients with chest pain of an etiology other than coronary ischemia, and could provide clinical utility complementary to that of cardiac troponins, the established markers of necrosis. Unbound free fatty acids (FFAu) and their intracellular binding protein, heart-type fatty acid–binding protein (H-FABP), have been suggested to have clinical utility as indicators of cardiac ischemia and necrosis, respectively.
Methods: We examined results of clinical assessments of FFAu and H-FABP as biomarkers of cardiac ischemia and necrosis. Data published on FFAu and H-FABP over the past 30 years were used as the basis for this review.
Results: Although little clinical work has been done on FFAu since the initial reports, recent studies documented an association between increased serum FFAs and ventricular dysrhythmias and death in patients with acute myocardial infarction (AMI). Recent data suggest that serum FFAu concentrations increase well before markers of cardiac necrosis and are sensitive indicators of ischemia in AMI. H-FABP is abundant in cardiac muscle and is presumed to be involved in myocardial lipid homeostasis. Similar to myoglobin, plasma H-FABP increases within 3 h after AMI and returns to reference values within 12–24 h.
Conclusions: FFAu may have a potential role in identifying patients with cardiac ischemia. H-FABP is useful for detecting cardiac injury in acute coronary syndromes and predicting recurrent cardiac events in acute coronary syndromes and in congestive heart failure patients. Assays are available for both markers that could facilitate further clinical investigations to assess their possible roles as markers of cardiac ischemia and/or necrosis.
142 citations
131 citations
TL;DR: The Multigenerational Interconnectedness Scale was administered to 2,893 Arab adolescents in eight Arab societies and found that adolescent-family connectedness differs significantly across the Arab societies as discussed by the authors.
Abstract: The Multigenerational Interconnectedness Scale was administered to 2,893 Arab adolescents in eight Arab societies. Results show that adolescent-family connectedness differs significantly across the Arab societies. Arabs scored higher in emotional, financial, functional, and total connectedness than Americans. Female adolescents were more connected than male adolescents in all three kinds of connectedness. A low but significant effect of urbanization was found on emotional and financial connectedness. First-born adolescents scored higher in financial connectedness. Further studies that employ additional tools such as interviews, observations, and parents’ self-report are needed.
107 citations
01 Oct 2006
TL;DR: The experiences in validating a number of model transformations are reported and three techniques that can be used for constructing test cases are proposed.
Abstract: Validation of model transformations is important for ensuring their quality. Successful validation must take into account the characteristics of model transformations and develop a suitable fault model on which test case generation can be based. In this paper, we report our experiences in validating a number of model transformations and propose three techniques that can be used for constructing test cases.
103 citations
TL;DR: It is reported that West Nile virus was vertically transmitted to 2 F(1) female Culex pipiens from a naturally infected female collected in Stratford, Connecticut, suggesting that WNV survives winter in unfed, vertically infected C. pipiens with amplification initiated in spring by horizontal transmission.
Abstract: West Nile virus (WNV) has become established in the northeastern United States, where mosquitoes are inactive during winter. There have been no documented studies to explain how this virus survives winter and reinitiates infection in spring. We report that WNV was vertically transmitted to 2 F(1) female Culex pipiens from a naturally infected female collected in Stratford, Connecticut. One vertically infected F(1) female, which was 168 days old, fed on a hamster that died 8 days later of West Nile disease. This suggests that WNV survives winter in unfed, vertically infected C. pipiens with amplification initiated in spring by horizontal transmission.
98 citations
TL;DR: These data show that mosquitoes become infected by means other than by blood feeding, possibly by transovarial transmission, and suggest that females in the canopy are seeking hosts, and after digestion of the bloodmeal and development of mature oocytes, they descend to catch basins for shelter and deposition of eggs.
Abstract: In total, 93,532 female mosquitoes (Diptera: Culicidae) were captured in traps placed in subterranean (catch basin), ground (approximately 1.5 m above ground), and canopy (approximately 7.0 m above ground) habitats in Stamford and Stratford, CT, during 2003-2005. Culex pipiens L. was the most abundant (64.8%) of the 31 species identified. Significantly greater numbers of Cx. pipiens were captured in canopy-placed mosquito magnet experimental traps, and significantly greater numbers were collected in catch basin-placed (Centers for Disease Control) CDC traps than in CDC traps placed elsewhere. Culex restuans Theobald was captured in significantly greater numbers in traps placed in catch basins. Aedes vexans (Meigen), Aedes cinereus Meigen, and Aedes cantator (Coquillett) were significantly more abundant in ground traps. In total, 429 isolations of West Nile virus (WNV) were made from seven species of mosquitoes from late June through the end of October during 2003 through 2005. Three hundred ninety-eight (92.8%) isolates were from Cx. pipiens. Others were from Cx. restuans (n = 16), Culex salinarius Coquillett (n = 5), Ae. vexans (n = 4), Ae. cantator (n = 3), Aedes triseriatus (Say) (n = 2), and Ae. cinereus (n = 1). Multiple isolates from Cx. pipiens were made each week, primarily during the later part of July through the end of September. Weekly minimum infection rates (MIRs) were lower in 2004 (highest weekly MIR = 7.1) when no human cases were reported in Connecticut in comparison with 2003 and 2005 (highest weekly MIR = 83.9) when human cases were documented. Frequencies of infected pools were significantly higher in Cx. pipiens captured in traps in the canopy and significantly higher in catch basin placed traps than in traps at ground level. The physiological age structure of Cx. pipiens captured in the canopy was significantly different from that of Cx. pipiens collected in catch basins. Invariably, Cx. pipiens captured in the canopy were nulliparous or parous with ovaries in Christophers' stage 2, whereas 58.7% of the females captured in catch basins possessed ovaries filled with mature oocytes in Christophers' stage 5. Our results suggest that females in the canopy are seeking hosts, and after digestion of the bloodmeal and development of mature oocytes, they descend to catch basins for shelter and deposition of eggs. WNV was isolated from three, one, and two pools of male Cx. pipiens captured in catch basin-, ground-, and canopy-placed traps, respectively, and from six nulliparous Cx. pipiens females collected in the canopy. Weekly MIR ranged from 1.2 to 31.1 per 1,000 male specimens. These data show that mosquitoes become infected by means other than by blood feeding, possibly by transovarial transmission. The placement of traps in tree canopies and in catch basins can be used to augment current practices of placement of traps near the ground for surveillance of mosquitoes infected with WNV and for studies of the ecology of WNV.
83 citations
TL;DR: In this article, women play central roles in establishing and managing these transnational households and their significance through an analysis of two groups of Somali women in Cairo within the domains of their transnational families and communities.
Abstract: Since the Somali Civil War in 1991 there have been a large number of Somalis living in the Middle East Europe North America and Australia. An increasing number of these Somalis are living in transnational households where family members live and sometimes move back and forth in different nation-states yet these families maintain strong ties share resources and make decisions collectively about the well-being of different members. In this paper I argue that women play central roles in establishing and managing these transnational households. I examine these roles and their significance through an analysis of the activities and experiences of two groups of Somali women in Cairo within the domains of their transnational families and communities. These groups of women are: (1) refugees who have been granted or are seeking asylum from the United Nations High Commissioner for Refugees (UNHCR) office in Egypt and (2) naturalized citizens of Western countries who have relocated to Egypt and whomI will refer to as emigres. I argue that many of these women become active members of transnational households and communities to (1) resist legal economic and/or cultural "othering" of host societies and (2) renegotiate past and present identity discourses that marginalize these individuals on multiple levels that are determined by clan affiliations socio-economic conditions and gender inequalities. By using complex transnational strategies these women are engaging in new forms of activism to establish lives with more security better future opportunities and more dignity for their families and themselves. Yet their transnational family and community lives have benefits and challenges which the women experience differently because of their varied diasporic histories and their uneven access to legal and social capital. (authors)
TL;DR: In this paper, three neural networks were developed to estimate the productivity, within a developing market, for formwork assembly, steel fixing, and concrete pouring activities in concrete-related activities in developing countries.
Abstract: To overcome the variability and the impact of subjective factors on the cost of concrete-related activities in developing countries, neural networks can offer a guiding tool. In this study, three neural networks were developed to estimate the productivity, within a developing market, for formwork assembly, steel fixing, and concrete pouring activities. Eighteen experts working in six projects were carefully selected to gather the data for the neural networks. Ninety-two data surveys were obtained and processed for use by the neural networks. Commercial software was used to perform the neural network calculations. The processed data were used to develop, train, and test the neural networks. The results of the developed framework of neural networks indicate adequate convergence and relatively strong generalization capabilities. When used to perform a sensitivity analysis on the input factors influencing the productivity of concreting activities, the framework has demonstrated a good potential in identifying trends of such factors.
TL;DR: Genetic algorithms are applied to the deterministic time-varying lot sizing problem with batch ordering and backorders and indicate that the GA outperforms the MSM in both responses, with a more robust performance.
TL;DR: In this article, the authors apply the Lie-group method for determining symmetry reductions of nonlinear partial differential equations, which is more general than the direct method for symmetry reductions, and the results are plotted.
TL;DR: The authors examines some of the more problematic aspects of recent efforts to integrate psychology and religion and points out that many religious people make different distinctions from psychology's main consumer and client, making it difficult to integrate them.
Abstract: This article examines some of the more problematic aspects of recent efforts to integrate psychology and religion. Specifically, many religious people—psychology's main consumer and client—make dif...
07 May 2006
TL;DR: Ethernet at gigabit speed is tested as a network for real-time control functions and non-real-time entertainment functions in car industry, and the end-to-end delays were below the maximum round-trip delays required by the system.
Abstract: The use of networks for communication between electronic control units has increased in car industry over the last two decades. Several types of networks were developed for this purpose. In this study, Ethernet at gigabit speed is tested as a network for such system. The use of Ethernet helps integrating real-time control functions and non-real-time entertainment functions. Two main scenarios were simulated using OPNET. The fist one simulates pure control networks on board of a moving vehicle. The second scenario is the same as the first one with an added video load to simulate on-board entertainment. Both simulations were successful, as the end-to-end delays were below the maximum round-trip delays required by the system.
TL;DR: In this paper, the boundary-layer equations for two-dimensional steady flow of an incompressible, viscous fluid near a stagnation point at a heated stretching sheet placed in a porous medium are considered.
Abstract: The boundary-layer equations for two-dimensional steady flow of an incompressible, viscous fluid near a stagnation point at a heated stretching sheet placed in a porous medium are considered. We apply Lie-group method for determining symmetry reductions of partial differential equations. Lie-group method starts out with a general infinitesimal group of transformations under which the given partial differential equations are invariant. The determining equations are a set of linear differential equations, the solution of which gives the transformation function or the infinitesimals of the dependent and independent variables. After the group has been determined, a solution to the given partial differential equations may be found from the invariant surface condition such that its solution leads to similarity variables that reduce the number of independent variables of the system. The effect of the velocity parameter λ, which is the ratio of the external free stream velocity to the stretching surface velocity, permeability parameter of the porous medium k1, and Prandtl number Pr on the horizontal and transverse velocities, temperature profiles, surface heat flux and the wall shear stress, has been studied.
TL;DR: The concept of poverty is discussed using qualitative and quantitative measures as an indicator for social deprivation as discussed by the authors, however, when closely examined, these dimensions are seen to be conceptually interrelated and complementary rather than substitutable.
Abstract: The concept of poverty is discussed using qualitative and quantitative measures as an indicator for social deprivation. Poverty can be absolute, relative, income based, consumption based, or entitlement based. The variation in the concept of poverty reveals its dimensionality. However, when closely examined, these dimensions are seen to be conceptually interrelated and complementary rather than substitutable. The concept used to define poverty determines the methods employed to measure it. Composite indicators can hide important policy messages inherent in their constituent variables.
TL;DR: Egyptian journalists gave prime importance to supporting Arabism/values and also performed this function most often, which may be useful in creating an understanding in the non-western world of how critical this issue is to the press and possibly therefore to the Egyptian public.
Abstract: This study reports on Egyptian journalists’ rating of various journalistic functions in terms of both importance and ability to perform these functions. The functions, rated for importance, coalesced into four factors, Sustain Democracy, Support Arabism/Values, Support Government and Provide Entertainment. Egyptian journalists gave prime importance to supporting Arabism/values and also performed this function most often. They considered democracy-sustaining functions second in importance, but were able to perform them least often, at about the average level. For all function factors, perceived importance was discrepant with actual amount of performance, with the latter always being lower. The study’s contribution lies in (1) the quantitative benchmarks it establishes for Egyptian journalism practice, (2) its inclusion of functions specific to Egyptian society and press as culled from the literature and (3) its finding of the prime placement by Egyptian journalists of the function support for the Palestini...
TL;DR: A solution containing chromate was treated using waste shot-blast fines recovered from surface finishing operations in a cast-iron foundry as a sorbent in batch and fixed-bed modes to produce a pH-adsorption edge that exhibits removal of chromium (Cr) over a broad pH range, with adsorption capacities that compare favorably to those reported for other adsorbents.
Abstract: A solution containing chromate was treated using waste shot-blast fines recovered from surface finishing operations in a cast-iron foundry as a sorbent in batch and fixed-bed modes. Equilibrium experiments for initial chromate concentrations of 5 to 10 ppm produced a pH-adsorption edge that exhibits removal of chromium (Cr) over a broad pH range, with adsorption capacities that compare favorably to those reported for other adsorbents such as activated carbon and commercial iron oxides. Surface complexation modeling of adsorption equilibria suggests the formation of monodentate, inner-sphere complexes with chromate (CrC 4 2- ) and bichromate (HCrO 4 - ). Adsorption of Cr(VI) at iron oxy-hydroxide sites appears to be the primary mechanism of chromium removal at neutral pH. At lower pH values (for example, pH 4), reduction to Cr(III) is assumed to contribute to the increasing removal as a function of decrease in pH. There is also evidence to support the formation of Cr(III)-iron (Fe)(III) coprecipitate following Cr(VI) reduction by dissolved Fe(II). Using equilibrium constants for the two surface complexation reactions evaluated from a triple-layer model description of the oxide-water interface, chromate removal in a short fixed bed of fines was simulated using a dual mass-transfer kinetic model. Rate coefficients determined from model calibration of the short column were used to predict experimental breakthrough curves in columns with empty bed contact times (EBCTs) up to four times the short column. For an influent chromium concentration and pH of 5 ppm and 7.0, respectively, a solid-phase loading capacity of 9.5 ± 0.3 mg/g was achieved at exhaustion. Predictive model runs indicate that, for this case, an EBCT of 2.0 to 2.5 minutes is optimum for achieving a target effluent concentration of less than or equal to 0.05 mg/L chromium as Cr(VI).
TL;DR: In this article, a simplified technique is presented to determine the shakedown limit load of a 90-degree pipe bend subjected to constant internal pressure and cyclic inplane closing bending moment using the finite element method.
Abstract: In this paper a simplified technique is presented to determine the shakedown limit load of a 90-degree pipe bend subjected to constant internal pressure and cyclic in-plane closing bending moment using the finite element method. The simplified technique determines the shakedown limit load without performing time consuming full elastic-plastic cyclic loading simulations or conventional iterative elastic techniques. Instead, the shakedown limit load is determined by performing two finite element analyses namely; an elastic analysis and an elastic-plastic analysis. By extracting the results of the two analyses, the shakedown limit load is determined through the calculation of the residual stresses developed in the pipe bend. In order to gain confidence in the simplified technique, the output shakedown limit moments are used to perform full elastic-plastic cyclic loading simulations to check for shakedown behavior of the pipe bend. The shakedown limit moments output by the simplified technique are used to generate the shakedown diagram of the pipe bend for a range of constant internal pressure magnitudes. The maximum moment carrying capacity (limit moment) the pipe bend can withstand and the elastic limit are also determined and imposed on the shakedown diagram of the pipe bend. In order to get acquainted with the simplified technique, it is applied beforehand to a bench mark shakedown problem namely, the Bree cylinder (Bree, J., 1967, J. Strain Anal., 3, pp. 226-238) problem. The Bree cylinder is subjected to constant internal pressure and cyclic high heat fluxes across its wall. The results of the simplified technique showed very good correlation with the analytically determined Bree diagram of the cylinder.
10 Apr 2006
01 Jan 2006
01 Jan 2006
TL;DR: Hybrid and monolithic thinned backside illuminated CMOS imagers operating at full depletion at low substrate voltages were developed in this article, where the combination of a 50?m EPI layer with varying doping concentration and trenches to reduce crosstalk is unique.
Abstract: Hybrid and monolithic thinned backside illuminated CMOS imagers operating at full depletion at low substrate voltages were developed. The combination of a 50 ?m EPI layer with varying doping concentration and trenches to reduce crosstalk is unique. All thin wafer processing is performed on 200 mm wafers using a specially developed temporary carrier process. As a result, working imagers exhibiting high pixel yield, high quantum efficiency and low dark current are demonstrated.
TL;DR: P pelvic floor disorders are one case that falls in the health status/roles of women and must be addressed from a broader outlook in women, not narrowly seen as only a health problem, which it undeniably is, but more so taking into consideration its ramifications and impact on women’s lives both in terms of cause and effect.
Abstract: In modern medicine especially, we see clearly that medicine is and must be a reflection of contemporaneous culture. We should teach our students, in light of history, that they must live up, not to the most conspicuous elements, but to the best that there is in their culture, should understand its weakness, and should try to correct some of the evils which too great loyalty to their culture may produce. [Emerson CP (1927) The historical method of teaching clinical medicine. In: Round table conference: 37th annual meeting, Cleveland, October 26, 1926. Bulletin of the Association of Medical Colleges, vol 2, pp 193–201] The art and science of medicine has evolved during the years through the encounter and cross-fertilization between philosophies, idealogies, and folkloric practices from different cultures and civilizations. The benefit of gaining valuable clinical information on women from conducting international research in several countries, indeed on a multinational patient population, as well as the important biological influences of sociodemographic, economic, genetic, and environmental factors are thus well recognized. The impact of sophisticated and often competing anthropologic and societal variables such as ethnicity, race, culture, religion, spirituality, geopolitical orientation, indigenous psychology, personality, and gender identity on individual’s realization of health role, experience of health and illness, and utilization of health services is, however, less appreciated in women health studies, particularly in urogynecology [1–5]. Pelvic floor health in women has a wider definition and includes not only the well-being of women, in terms of appropriate urinary and fecal control, integrity of pelvic organ support, and sexual health but also the drive towards safer and less traumatic childbirth and hence improvement in practice, management, and conduct of labor and delivery. Pelvic floor health must thus be addressed from a broader outlook in women, not narrowly seen as only a health problem, which it undeniably is, but more so taking into consideration its ramifications and impact on women’s lives both in terms of cause and effect. In this context, pelvic floor disorders are one case that falls in the health status/roles of women. The health status in any one society cannot be understood apart from the cultural factors that determine not only the individuals’ attitudes towards health matters but also the behavior of these individuals in seeking health care. Culture embodies those values, religious, and otherwise that constitute the background to individuals’ health attitudes and behaviors. The specific nature of the male-dominated Middle Eastern culture—patriarchy—where religion plays an important role and where women’s roles are as such delineated represents a strong factor in shaping the health behavior of women in the region [6, 7]. Attitudes towards pregnancy, childbirth, and the whole issue of women’s health are necessarily rooted in the broader milieu of culture. Studies in the field of sociology/anthropology covering Middle Eastern countries have further revealed that the formal health services may be bypassed and underutilized, even when available, while the major health care provider is the traditional system. If in all areas of health care this attitude tends to prevail, it is more common where women’s health is concerned [6, 7]. The social proximity between the clients on the one hand and the providers on the other may be seen as a reason for this finding. The fact remains, however, that the attitudes of Middle Eastern women towards health matters and correspondingly health Declaration: The opinions expressed in this manuscript reflect those of the authors and not necessarily their institution
TL;DR: In this paper, the possibility of treating PECVD-enhanced chemical vapor deposited (PECVD) silicon germanium (Si1−xGex) thin films with a pulsed excimer laser for obtaining good MEMS structural layers was studied.
Abstract: This work studies the possibility to treat plasma enhanced chemical vapor deposited (PECVD) silicon germanium (Si1−xGex) thin films grown at 400 °C or lower with a pulsed excimer laser for obtaining good MEMS structural layers. The main advantage of using PECVD is that a high growth rate (∼35 nm/min) can be achieved at low temperatures (≤370 °C). It is demonstrated that optimizing the pulse fluence, number and rate yields high quality films characterized by a low defect density (∼102 defect/cm2), large grains (∼300 nm), a low mean stress and a low stress gradient. Furthermore, the electrical resistivity of the as grown material, deposited at 210 °C, is reduced from 12 kΩ cm to 1.3 mΩ cm after laser annealing.
10 Apr 2006
TL;DR: In this paper, the authors argue that Egypt's implementation of an economic reform and structural adjustment program since 1991 has not led to a reduction of its hegemony over certain welfare services, such as education and health care.
Abstract: This article argues that Egypt's implementation of an economic reform and structural adjustment programme since 1991 has not led to a reduction of its hegemony over certain welfare services. Yet its role in the provision of free health and educational services has been drastically curtailed. This is evident if the pre- and post adjustment situations are analysed in terms of the poor's access to education and health services. The introduction of cost recovery measures has negatively impacted on the poor and increased their vulnerability to exploitation by exposing them to a wide range of ‘hidden’ and informal fees. Further, the introduction of special policies designed to mitigate the rising costs of education and health care are not being implemented due to a set of institutional and political reasons. The consequences of the increasing privatisation of educational and health services on the poor are examined by looking at the detail of those living in the densely populated community of Bulaq el Dakrour i...
TL;DR: In this paper, instead of using the diagonal elements of the projection matrix as a measure of leverage, the robust distance proposed by Hadi (1992a, 1994) was used to eliminate the distortion effect of masking by constructing a measure for the observed points which is free from the effects of multivariate outliers and clustering in the X-space.
Abstract: Chatterjee and Machler (1997) propose an iteratively weighted least squares procedure as a robust fit for linear models. The weights are a function of leverage and residuals. The standard measure of leverage (the diagonal element of the projection matrix) as is well known, can be distorted by the presence of collection of points which individually have small leverage values but collectively forms a high leverage group (“masking points”). The Chatterjee-Machler procedure is not very effective when there is extensive masking. We present a procedure which works in the presence or absence of masking. In the proposed new procedure, instead of using the diagonal elements of the projection matrix as a measure of leverage, we use a robust distance proposed by Hadi (1992a, 1994). This measure eliminates the distorting effect of masking by constructing a measure of location and dispersion for the observed points which is free from the effects of multivariate outliers and clustering in the X-space. The metho...
TL;DR: In this paper, the authors used the finite element method to determine the shakedown limit moment of a long radius 90-degree pipe bend using two different techniques, a simplified technique which utilizes small displacement formulation and elastic-perfectly-plastic material model and an iterative based technique which incorporates large displacement effects accounting for geometric nonlinearity.
Abstract: In this paper the shakedown limit load is determined for a long radius 90-degree pipe bend using two different techniques. The first technique is a simplified technique which utilizes small displacement formulation and elastic-perfectly-plastic material model. The second technique is an iterative based technique which uses the same elastic-perfectly-plastic material model, but incorporates large displacement effects accounting for geometric non-linearity. Both techniques use the finite element method for analysis. The pipe bend is subjected to constant internal pressure magnitudes and cyclic bending moments. The cyclic bending loading includes three different loading patterns namely; in-plane closing, in-plane opening, and out-of-plane bending. The simplified technique determines the shakedown limit load (moment) without the need to perform full cyclic loading simulations or conventional iterative elastic techniques. Instead, the shakedown limit moment is determined by performing two analyses namely; an elastic analysis and an elastic-plastic analysis. By extracting the results of the two analyses, the shakedown limit moment is determined through the calculation of the residual stresses developed in the pipe bend. The iterative large displacement technique determines the shakedown limit moment in an iterative manner by performing a series of full elastic-plastic cyclic loading simulations. The shakedown limit moment output by the simplified technique (small displacement) is used by the iterative large displacement technique as an initial iterative value. The iterations proceed until an applied moment guarantees a structure developed residual stress, at load removal, equals or slightly less than the material yield strength. The shakedown limit moments output by both techniques are used to generate shakedown diagrams of the pipe bend for a spectrum of constant internal pressure magnitudes for the three loading patterns stated earlier. The maximum moment carrying capacity (limit moment) the pipe bend can withstand and the elastic limit are also determined and imposed on the shakedown diagram of the pipe bend. Comparison between the shakedown diagrams generated by the two techniques, for the three loading patterns, is presented.Copyright © 2006 by ASME