DCCs among Sector Indexes and Dynamic Causality between Foreign Exchange and Equity Sector Volatility: Evidence from Egypt

The objective of the current paper is to explore the co-movements between domestic equity sectors in the Egyptian Exchange (EGX), using the dynamic conditional correlation (DCC) model, and to examine the time-varying causal links between the exchange rate volatility (EXVOL) and sector volatility (SVOL) using the bootstrap Granger non-causality tests in a bivariate VAR, where conditional volatility series are extracted from GARCH(1,1) model. We employ weekly data. Results show that all estimated DCCs are positive with a clear heterogeneity between the sector pairs. They do not exhibit stable correlation pattern for a prolong time, implying that DCC estimates change in response to price increment shocks to each sector in the pair. Hence, the assumption of static inter-sectoral correlations between domestic sector indexes is invalid when forming and periodically re-balancing portfolios. The global financial crash and the political instability in early 2011 have significantly increased the level of DCCs for four and ten out of fifteen pairs, respectively. Thus, the recent political turmoil in Egypt has widely affect diversification opportunities in the EGX whereas the global financial crash has not. The volatility transmission between SVOL and EXVOL is subject to structural breaks. The bootstrap rolling window estimations show that the casual relationship between SVOL and EXVOL varies across time. These findings would be of great importance to market participants in their hedging and investment decisions since investors and firms are more concerned with industrial sector exposure estimates

Patient satisfaction with quality of primary health care in Benghazi, Libya

Introduction: The Libyan National Health System (LNHS) is debated for the paradox of its performance versus impact. It has poor performance, but the national health statistics are good and competitive. There are concerted efforts to manage health care services and to regain the lost trust. A primary health care (PHC) system that focuses on preventive and promotive care is the core focus of LNHS efforts. Objectives: To assess patient satisfaction with quality of PHC assessed in terms of (a) customer profile, (b) patient satisfaction, and (c) health care-seeking behavior. Methodology: A sample of nine health centers and seven polyclinics from various locations in Benghazi, Libya were selected for gathering information by structured face-to-face interviews. A total of 310 beneficiaries were interviewed by using an Arabic translation of the Charleston Psychiatric Outpatient Satisfaction Scale. Results: The beneficiaries appear to be quite satisfied with the quality of services. Geographical zone, marital status of beneficiary, and type of facility are satisfaction-related factors. There are preferences for facilities located within the City Centre over those located elsewhere. There is also an interaction effect of the geographical zone and the type of facility in creating differences in satisfaction. Conclusions: A customer-friendly facility concept that emphasizes reception, physician interaction, and cordiality shall add value. Polyclinics require more attention as does the Al Slawy area. A few utility services might also be considered.Keywords: exit interviews; Health For All by All; geographic zone; administrative and environmental factors; health-seeking behavior; interaction effect; type and location of facility; place of residenc

Assentication: User Deauthentication and Lunchtime Attack Mitigation with Seated Posture Biometric

Biometric techniques are often used as an extra security factor in authenticating human users. Numerous biometrics have been proposed and evaluated, each with its own set of benefits and pitfalls. Static biometrics (such as fingerprints) are geared for discrete operation, to identify users, which typically involves some user burden. Meanwhile, behavioral biometrics (such as keystroke dynamics) are well suited for continuous, and sometimes more unobtrusive, operation. One important application domain for biometrics is deauthentication, a means of quickly detecting absence of a previously authenticated user and immediately terminating that user's active secure sessions. Deauthentication is crucial for mitigating so called Lunchtime Attacks, whereby an insider adversary takes over (before any inactivity timeout kicks in) authenticated state of a careless user who walks away from her computer. Motivated primarily by the need for an unobtrusive and continuous biometric to support effective deauthentication, we introduce PoPa, a new hybrid biometric based on a human user's seated posture pattern. PoPa captures a unique combination of physiological and behavioral traits. We describe a low cost fully functioning prototype that involves an office chair instrumented with 16 tiny pressure sensors. We also explore (via user experiments) how PoPa can be used in a typical workplace to provide continuous authentication (and deauthentication) of users. We experimentally assess viability of PoPa in terms of uniqueness by collecting and evaluating posture patterns of a cohort of users. Results show that PoPa exhibits very low false positive, and even lower false negative, rates. In particular, users can be identified with, on average, 91.0% accuracy. Finally, we compare pros and cons of PoPa with those of several prominent biometric based deauthentication techniques

Transience of Seawater Intrusion and Retreat in Response to Incremental Water Level Variations

This paper provides for the first time an experimental study where the impact of sea level fluctuations and inland boundary head level variations on freshwater-saltwater interface toe motion and transition zone dynamics were quantitatively analyzed under transient conditions. The experiments were conducted in a laboratory flow tank where various (inland and coastal) head changes were imposed to the system and the response of the key seawater intrusion parameters were analysed with high spatial and temporal resolution. Two homogeneous aquifer systems of different grain size were tested. The numerical code SEAWAT was used for the validation. The results show that in cases of sea level variations, the intruding wedge required up to twice longer time to reach a new steady state condition than the receding wedge, which thereby extend the theory of timescale asymmetry between saltwater intrusion and retreat processes in scenarios involving sea level fluctuations. The intruding and receding rates of the saltwater wedge were respectively similar in the scenario involving sea level and the freshwater level changes, despite change in transmissivity. The results show that, during the intrusion phase, the transition zone remains relatively insensitive, regardless of where the boundary head change occurs (i.e. freshwater drop or sea level rise) or its magnitude. By contrast, a substantial widening of the transition zone was observed during the receding phase, with almost similar amplitude in the scenario involving a rise of the 2 freshwater level compared to that caused by a drop of the saltwater level, provided an equivalent absolute head change magnitude was used. This transition zone widening (occurring during saltwater retreat) was greater and extended over longer period in the low hydraulic conductivity aquifer, for both freshwater level rise and sea level drop scenarios. The concentration maps revealed that the widening mechanism was also enhanced by the presence of some freshwater sliding and into the wedge during saltwater retreat, which was thereafter sucked upward toward the interface because of density difference effects

Description of the normal variants of the anatomical shapes of the sella turcica using plain radiographs: experience from Sokoto, Northwestern Nigeria

Background: The anatomy of the sella turcica is variable in size and shape. It has been classified into three types: round, oval and flat. It can also be deep or shallow in both children and adults. The floor of the sella turcica which in most cases is concave may be, flat or even convex. In both anatomical and radiological practice in Nigeria, normal data in relation to the description of the normal variants of the anatomical shapes of the sella turcica are based on Caucasian studies.Methods: All available lateral skull radiographs of subjects over a 3-year period, from 2002 to 2004, were retrieved from the Radiology Department of the Usmanu Danfodiyo University Teaching Hospital, Sokoto for the study. Radiographs were mounted on the viewing boxes and sellae turcicae were studied and classified.Results: A total of 228 subjects were involved in this study. Of this figure, 171 (75%) were males, and 57 (25%) were females (m: f ratio = 3:1). The predominant shape of sella in the African subjects studied is oval, and the difference in frequency of oval shaped sella and that of round or flat types is highly statistically significant.(PArrière Plan: L\'anatomie de sella turcica varie selon la forme et la plat. Elle peut aussi être profonol ou plat, aussi chez les enfants que chez les adults. Le planche de sella turcica, qui est généralement concave peut être convexe, ou plat de forme. Bien en anatomie et en radiologie practiques au Nigéria. Les données relatives à la description des variants normales de formes anatomiques de sella turcica sont basées sur des études caucasiennes.Méthodes: Toutes les radiographes laterales du été collectées du departement de 3 ans (2002 a 2004) ont été collectées du departement de Radiologie de centre uiversitaire hospitalier de université Usmanu Danfodiyo pour cette étude. Les radiographes ont été montées sur les boîtes de visualization et sella turcica ont étés étudiées et classifiées.Resultats: Un total de 228 sujets ont été impliqués dans cette étude. De ce total, 171 (75%) étaient males, et 57 (25%) étaient femelles (m: f ratio = 3:1). La forme predominante de sella turcica pour les sujets africains étudiés est ovale, et la différence en frequence entre sella à forme ovale et sella à forme ronde ou plate est statistiquement très élevée. (PL 0.001). Le plancher de sella de plus commun pour les sujets africains étudiés est concave et la différence en frequence entre sella a plancher cancave sella à plancher convexe is statistiquement ties élevée. (PL 0.001).pour les deux cas de formes plancher de sella turcica et les différents types de plancher de sella turcica, en ce qui est du sex des sujets étudiés, la différence en frequence entre les mâles et les femelles est statistiquement très élevée. (PL 0.001).Conclusion: Il est concluque la predominance et relativité des frequences de variantes normales de formes anatomiques de sella turcica considérées dans cette étude surdes sujets Nigérians est similaire à celle considérées pour les “caucasians”. Des études plus poussées sur un champ plus étendu sont nécessaires pour confirmer nos decouvertes Keywords: Description, normal variants, anatomical shapes, sella turcica Annals of African Medicine Vol. 7 (2) 2008: pp. 77-8

Studies on risk factors of mortality in lambs in Sokoto, Nigeria

Mortality in lambs is complex problem which may result from a variety of climatic, nutritional, management, infectious, genetic and other factors. Associated with death are other factors which could be of maternal or lamb origin that predisposes the young lamb to early death. Records of sex, breed, age, birth weight, type of birth, season of birth and age of ewe from 82 lambs that were dead and posted are recorded and analyzed as the associated risk factors contributing to mortality in these lambs. More male lambs died 49 (59.76%) compared to females 33 (40.24%) whilst mortality in lambs aged 0-7 days was 40 (48.78%). The effect of birth weight showed 47 (57.31%) mortalities in lambs less than 2kg at birth. Higher deaths were seen during the wet season 37 (45.12%) than during cool and hot seasons. Mortality was more in Uda breeds 29 (35.37%) than in other breeds. The outcome of the study showed that the knowledge of when and how mortality occurs could be helpful and to reduce mortality, the management of lambs particularly at early age is imperative

Adolescent malnutrition: Prevalence and pattern in Abuja Municipal Area Council, Nigeria

Objective: To determine the prevalence and pattern of malnutrition among adolescents in senior secondary schools in The Abuja Municipal area councilMethods: Study design: this is a cross-sectional study conducted among adolescents (10-19 years) in secondary schools. A multistage sampling technique was employed to select a total of 1700 students from classes in selected schools. All schools in the Abuja Municipal Area council (AMAC) were stratified into urban and rural schools. Eight schools were selected by balloting from a list of schools obtained from the Education centre. A school was selected from each of the four major districts of AMAC and four schools were selected from the rural making a total of 8 schools. Although the consent of the school authorities was obtained, individual subject also consented to the study before being enrolled. The study excluded those adolescents who were physically challenged thus limiting physical activity. Information was obtained via the use of questionnaires that were administered by trained personnel. Subject’s height and weight was taken using the floor-type height (H) and weight (W) measuring scale model ZT-120 using Massachusetts department of public health protocol. The nutritional status was determined using the formula: BMI= W/H2 , where W =weight (in kilograms) and H= height (in meters). The age and sex specific height and BMI percentile for each subject was determined using the 2007 WHO Height and BMI growth charts for age 5-19years. The students were then classified into one of the following categories using previously used standards: normal, stunted, wasted, overweight or obese. Data was analyzed using SPSS version 17 statistical package.Results: The mean age was 14.43±1.94 years; male 688, female 862, M:F ratio 1.1.3. Mean BMI, weight and height were 20.31±3.07kg/m2, 51.07± 10.80 kg, and 157.88±9.33 cm. The prevalence of wasting, stunting, overweight and obesity was documented as 1.7% (27/1550), 11.3% (175/1550), 13.2% (205/1550), and 2.6% (41/1550) respectively. Those in urban schools had higher mean BMI (20.91±3.22 kg/m2 versus 19.71±2.78 kg/m2) and height (160.41±9.14 cm versus 155.32±8.81 cm) and p values <0.05.Conclusion: There is a double burden of over-nutrition (overweight and obesity) and under-nutrition (stunting and wasting) among adolescents in Nigeria.Key words: Adolescent, malnutrition, school populatio

Seroprevalence of Varicella Zoster Virus Infection among Primary school Children In Northern Nigeria

Background: Varicella Zoster infection occurs exclusively in man and commonly affects children with predilection for school age children. Following infection the course of the disease in immunocompetent children is often mild and self limited but in older age groups infection may be severe with poor outcomes ranging from complicating bacterial morbidities to death. In Kaduna State, Northern Nigeria the seroprevalence ofVaricella - zoster virus (VZV) infection is unknown The current cross - sectional study was conducted to assess the seroprevalence of VZV infection among nursery and primary school pupils in Kaduna State. Mathods: Nursery and primary school pupils between the ages 4 and 15 years were randomly selected from the three geopolitical zones of Kaduna State . Demographic data on each subject  were obtained by administration of a questionnaire and blood samples were collected for serum analysis of Varicella - zoster virus immunoglobulin G (IgG) using the Automat ion ELISA IgG Kit manufactured by Automation INC. USA. Data obtained were summarized using percentages and frequency tables. Results were analyzed using Epi- info version 3.0. Results: Three hundred and fifty three pupils were recruited for the study. The overall prevalence rate for VZV infection was 66.3% with the value in males being 68.5% and in females 63.9%. The prevalence of VZV infection increased with age in both sexes. A high percentage of children (60%) were seropositive at 4-6 years. Conclusion: The study shows a 66.3% prevalence of VZV infection among children in Kaduna State. Thi s high pr eva l enc e r a t e necessitates further studies to establish the burden of the problem in Nigeria and rationalize the institution of preventive measures against the infection, particularly immunocompromi sed young children

Advanced central nervous system imaging biomarkers in radiologically isolated syndrome: a mini review

Radiologically isolated syndrome is characterised by central nervous system white-matter hyperintensities highly suggestive of multiple sclerosis in individuals without a neurological history of clinical demyelinating episodes. It probably represents the pre-symptomatic phase of clinical multiple sclerosis but is poorly understood. This mini review summarises our current knowledge regarding advanced imaging techniques in radiologically isolated syndrome that provide insights into its pathobiology and prognosis. The imaging covered will include magnetic resonance imaging-derived markers of central nervous system volumetrics, connectivity, and the central vein sign, alongside optical coherence tomography-related metrics

Isolation, Characterization and Antibiotic Susceptibility Pattern of Escherichia coli from Diarrhoeic Lambs in Sokoto, Northwestern Nigeria

A total of 127 faecal samples were collected from diarrhoeic lambs and examined for Escherichia coli. The bacterial culture involved pre-enrichment in peptone water before C incubation at 37 for 24 hours. Out of the isolates obtained, 42 (36.84%) were positive for Escherichia coli. Characterization of the isolates revealed serotypes O157 (13), O118 (9), O111 (8), O26 (7), and O103 (5) as the most frequent strains. Their prevalence rates being 31.0%,21.4%, 19.0%, 16.7% and 11.9% respectively. Minimum Inhibitory Concentration (MICs) of the E coli strains to six antibiotics revealed tetracycline as having the lowest MIC, which ranged from 3.12ìg/ml - 50ìg/ml followed by chloramphenicol with an MIC ranging between 6.25ìg/ml -100ìg/ml. It was concluded that there was need for further research to study the pathogenicity of the E coli strains and that resistance to antibiotics was a problem which might have resulted from indiscriminate use of these drugs