Phytochemical analysis, cytotoxicity and genotoxicity of Psidium guajava L. (Myrtaceae) leaf extracts

Psidium guajava is one of the oldest and widely used medicinal plants in the world. The leaves, bark, roots and immature fruits are used in African ethno-medicine because of their anti-inflammatory, anti-diarrhoeal and anti-microbial properties amongst others. The aim of this work was to determine the phytochemical profile of locally sourced mature Psidium guajava leaves and to also evaluate the cytotoxic and genotoxic properties of aqueous extracts of Psidium guajava leaves. Ethanol extracts of Psidium guajava leaves were subjected to analysis using GC-MS. Aqueous extracts were prepared by boiling pre-weighted fresh leaves in tap water and subsequently used in the Allium cepa assay. Analysis revealed terpene compounds (80.6%) as the most abundant phytochemical in ethanol extracts of the leaves. The results also revealed an overall significant concentration and time-dependent reduction in mitotic index (p ≤ 0.05). The value of EC50 was estimated to be 54.4 g/l. Examination of treated Allium cepa root tip cells revealed chromosomal aberrations including binucleation, bridges, distorted anaphase, clumping, vagrant chromosomes and c-mitosis. Aqueous leaf extracts of Psidium guajava leaves have genotoxic and cytotoxic potentials which should be seriously considered in its therapeutic applications

P A NEW CLASSES OF ANALYTIC FUNCTIONS

Abstract: Inequalities conditions for certain new classes of univalent functions were determined. Also,the distortion inequalities for the the new class of univalent functions was established

Sleep hygiene index: psychometric characteristics and usefulness as a screening tool in a sample of Nigerian undergraduate students

STUDY OBJECTIVES:The objectives of this study were to investigate the psychometric properties of the Sleep Hygiene Index (SHI) and determine its capacity to screen for poor sleep quality in a nonclinical sample of Nigerian university students. METHODS:A total of 348 students appropriately completed the SHI, the Morningness-Eveningness Questionnaire (MEQ), the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). RESULTS:The internal consistency (Cronbach alpha) of the SHI was .64 and its construct validity was modestly satisfactory. It had a significant negative correlation with the MEQ (r = −.170, P < .001) and positive correlations with global PSQI (r = .289, P < .001) and ESS (r = .219, P < .001) scores. Prior to the factor analysis, our sample was randomly divided into two. In one half of the sample (sample 1), exploratory factor analysis of the SHI items yielded a three-factor model. Confirmatory factor analysis on the other half (sample 2) corroborated this model with satisfactory indices of fitness (c2 = 67.805; df = 55; c2/df = 1.233; P = .115; goodness of fit index = .943; Tucker-Lewis index = .958; incremental fit index = .972; comparative fit index = .970; root mean square error of approximation = .037). A cutoff total score of 16 on the SHI had the best sensitivity (77.0%) and specificity (47.5%) to identify students who were categorized as experiencing poor sleep quality, according to the PSQI (area under the curve = 0.65, 95% confidence interval = 0.59–0.71). CONCLUSIONS:The SHI exhibited satisfactory psychometric properties as a self-rated assessment instrument in the evaluation of sleep hygiene and as a screening instrument for poor sleep quality among Nigerian undergraduate students

Korkeakoulutuksen kehittäminen : mihin suuntaan ja millä ehdoilla?

The rise in global cases of emergencies as a result of man-made and natural disaster necessitates the need for a robust and reliable means of communication networks. The partial or complete, disruption of telecommunications infrastructure as a result of disaster has caused delays in emergency response and disaster relief efforts, leading to loss of lives and damage to properties. Although, modern telecommunications networks have reliability and resiliency to physical damage, however, the risks associated with communications failures remain a major issue as the severity of the damages may depend on the underlying technologies and architecture used. It is however important to also note that each technology option available for public safety network has its own unique characteristics. Some of these options are widely deployed for commercial purposes in Nigeria, while others are still in the developmental stages.&nbsp;This paper therefore outlines some of the existing, new and affordable technological options, available today that can be deployed for public safety and disaster telecommunications networks in Nigeria. Furthermore, the paper recommends that the national broadband network plan needs to be aligned to the current commercial deployments of the 4G Long Term Evolution (LTE) wireless services, this is to ensure that the pace is maintained with the changes in the technology and leveraging cost efficiencies for the public safety networks

Utilization of Iron Filings as Partial Replacements for Sand in Self-Compacting Concrete

The use of industrial by-products in concrete production is part of concerted efforts on the reduction of environmental hazards attributed to the mining of conventional aggregates. Consideration of iron filings (IF), a by-product from steel production process, is an environmentally friendly way of its disposal which is expected to yield economic concrete production. Six self-compacting concrete (SCC) mixes were made by partially substituting river sand with IF at 5%, 10%, 15%, and 20% and the mix without IF (0% IF) served as the control. The water-binder (w/b) ratio of 0.45 was adopted for all mixes. The fresh state properties of SCC evaluated include: filling ability determined using slump flow and T500 mm slump flow tests, passing ability determined using L-box test and segregation resistance determined using V-funnel tests. The strength properties of SCC considered were compressive and tensile strengths. All the SCC mixes met the fresh properties requirements for filling capacity, passing ability, and segregation resistance. The 28-day compressive and tensile strengths of SCC increased by 3.46% and 8.08%, respectively, with IF replacement up to 15% compared to the control SCC. However, there was reduction in compressive and tensile strengths of SCC with IF replacement beyond 15%. The strength properties of SCC is considerably enhanced with the addition of up to 15% IF. Hence, the optimum content of 15% IF is considered suitable as a replacement for river sand in SCC. Keywords: Self-compacting concrete; iron filings; fine aggregates; filling ability; passing abilit