Efficiency of cache-replacement algorithms while retrieving data from a relational database and XML files in a web based system

Caching has been applied in Web based information systems in order toreduce the transmission of redundant network traffic and response latency by savingcopies of the content obtained from the Web closer to the end user. The efficiencyof caching is influenced to a significant extent by the cache replacement algorithmswhich are triggered when the cache becomes full and old objects must be evicted tomake space for the new ones.This paper presents a framework that can be used in future work to tunecache-replacement algorithms while data is simultaneously retrieved from arelational database and XML files in a web based environment, by a large numberof end-users. Three replacement policies are considered: Least Recently Used(LRU), Least Frequently Used (LFU) and Lowest Latency First (LLF). Theexperimental results obtained from the framework show that data caching greatlyimproves the overall performance of web based systems, and the type of the appliedcache replacement policy also plays an important role in the performance. In thescenarios considered in this paper, the LLF algorithm produced the bestperformance when retrieving data from a relational database, while the LFUalgorithm was the most efficient algorithm when data was retrieved from an XMLfile

The declining HIV seroprevalence in Uganda: what evidence?

Papers presented at the ninth International Conference on AIDS and STDs in Africa, held at Kampala in December 1995, show that HIV prevalence has apparently been on a downward trend in several sectors of the population of Uganda over the past few years. This article reviews the relevant presentations

Changes in climatic factors and malaria in Uganda

The study examines the relationship between climatic factors and reported malaria cases using data from 12 districts in Uganda over the period 2000-2011. A panel dataset comprising temperature, temperature standard deviation; minimum humidity; maximum humidity; precipitation; precipitation standard deviation; malaria cases; health facilities; hospital beds; health workers; per capita health expenditure and gross domestic product per capita. The Fixed Effects Model was found to be preferable. Health facilities, per capita GDP, the interaction of temperature and precipitation, the interaction of precipitation and variability in precipitation, maximum and minimum humidity have a significant positive effect on malaria cases. Hospital beds and health workers are significant and negatively related to malaria cases while per capita health expenditure, temperature, precipitation and variability in temperature have no effect

Is birth weight associated with blood pressure among African children and adolescents? A systematic review.

There is substantial evidence of an inverse association between birth weight and later blood pressure (BP) in populations from high-income countries, but whether this applies in low-income countries, where causes of low birth weight are different, is not certain. OBJECTIVE: We conducted a review of the evidence on the relationship between birth weight and BP among African children and adolescents. Medline, EMBASE, Global Health and Web of Science databases were searched for publications to October 2016. Papers reporting the relationship between birth weight and BP among African children and adolescents were assessed. Bibliographies were searched for further relevant publications. Selected papers were summarized following the preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines. In total, 16 papers from 13 studies conducted in nine African countries (Nigeria, Republic of Seychelles, Gambia, Democratic Republic of Congo, Cameroon, South Africa, Algeria, Zimbabwe and Angola) were reviewed. Eight studies were cohorts, while five were cross-sectional. The relationship between birth weight and later BP varied with age of the participants. Studies in neonates showed a consistently positive association, while predominantly inverse associations were seen among children, and studies in adolescents were inconsistent. Based on the limited number of studies identified, the relationship between birth weight and later BP may vary with age in African children and adolescents. Not all studies adequately controlled for confounding, notably gender or age. Whether the inverse relationship between birth weight and BP in later life observed in Western settings is also seen in Africa remains unclear

Adolescent sexual networking and HIV transmission in rural Uganda

Information on 861 adolescents shows that in 1991 36 per cent reported having been sexually active in the previous 12 months, but only 6.2 per cent had ever used a condom (11% males, 2.4% females). The HIV infection rate was 5.9 per cent overall, 0.8 per cent in males and 9.9 per cent in females. The proportion sexually active and the rate of HIV infection rise with age. The annual incidence of HIV infection was 2.0 per 100 person-years of follow-up among all adolescents, 0.8 in males and 3.0 in females. The annual mortality rate among HIV-negative adolescents was 0.37 per cent versus 3.92 per cent among the HIV-positive adolescents, a rate ratio of 10.6. Sexual network data were collected on 389 adolescents aged 15-19 years of whom 55 per cent were sexually active. The median age of first sexual intercourse was 15 years in either sex. The 214 adolescents reported 339 sexual relationships of which 38.5 per cent were with spouses, 36 per cent with boy or girl friends and 21 per cent with ‘friends’. There were 52 concurrent sexual relationships reported by 35 adolescents. Males report higher rates of concurrent sexual relationships than females. The sexual partners of boys were mainly younger students and housemaids while the girls’ partners were mainly older traders and salaried workers. Adolescents in this community report high rates of sexual activity and have complex sexual networks. They probably are important in the dynamics of HIV infection

Condition assessment of existing regional and rural roads in Albania

The conditions of roads are facing problems for many developed countries. In order to complement poverty reduction strategies and progressing as developed country, regional and rural transport interventions must be an integral part of such development interventions and focus on the mobility and access needs of communities. Substantial gains in accessibility—for more communities, in more regions of our country—are possible if regional and rural transport infrastructure interventions are designed in a least-cost, network-based manner focusing on reducing economic inequality and willing to maintain the service. In view of budget constraints, selecting interventions requires a participatory physical planning process undertaken jointly with concerned local governments and communities, supported and coordinated by regional or central government agencies. The roads in Albania had been constructed with different standards in different periods and exposed traffic loads which have rapidly increased during last two decades. Despite the fact that existing condition of some roads have been considered by ADF, an attempt was made on this study to draw a general picture of Albanian’s Roads. The condition of Albanian Roads was presented in this paper based on visual inspection of 1000 km roads, from different areas that are part of the country, concentrating on their conditions. Study concludes that general physical state of the roads are improved consider five years before, therefore, the service provided by such roads is affecting safety and we identified the opportunity to improve maintenance as the key factor for roads condition. Resources are scarce. In this context, participatory selection procedures and analytical prioritization tools are presented, and examples given, which take into account the social and economic importance of regional and rural transport infrastructure

Extreme case of Faraday effect: magnetic splitting of ultrashort laser pulses in plasmas

The Faraday effect, caused by a magnetic-field-induced change in the optical properties, takes place in a vast variety of systems from a single atomic layer of graphenes to huge galaxies. Currently, it plays a pivot role in many applications such as the manipulation of light and the probing of magnetic fields and material's properties. Basically, this effect causes a polarization rotation of light during its propagation along the magnetic field in a medium. Here, we report an extreme case of the Faraday effect where a linearly polarized ultrashort laser pulse splits in time into two circularly polarized pulses of opposite handedness during its propagation in a highly magnetized plasma. This offers a new degree of freedom for manipulating ultrashort and ultrahigh power laser pulses. Together with technologies of ultra-strong magnetic fields, it may pave the way for novel optical devices, such as magnetized plasma polarizers. In addition, it may offer a powerful means to measure strong magnetic fields in laser-produced plasmas.Comment: 18 pages, 5 figure