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Population distribution and threats to sustainable management of selected non-timber forest Products in tropical lowland rainforests of South Western Nigeria
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Effects of waste glass powder as pozzolanic material in saw dust cement brick
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- "The present study represents an attempt at contributing to literature by addressing an under researched topic of considerable health concern. The study investigated the psychological consequences of wife abuse in three high density residential areas' in Ibadan North Local Government Area of Ibadan. Four hundred and eighty women who were visited at home by the researchers participated in the study. Participants' mean age was 35.4 years with a standard deviation of 6.27. Interviews were conducted for participants, using standard and widely used measures of depression, self-esteem and wife abuse. Results indicated that all the participants reported at least some forms of spousal abuse. However, women who reported severe abuse were significantly higher on the depression measure, t(2,478)=-to.22;P<.01 than those who reported mild abuse. Results also showed that old abused women scored significantly lower on depression than young abused women, F(1,337)=P<.01. Likewise, high education abused women self reported significantly higher on depression than low education abused women, t(2,337)= 5.44. On self-esteem, old abused women were significantly higher than their young abused counterparts, t(2,337)=P<.05. Educational status also had significant effect on self-esteem, t(2,337)=7. 10, with low education women scoring significantly higher on self-esteem than high education women. The implication of this is that wife abuse negatively impact on abused women's self-esteem and depression, and that the effect is more on young, highly educated women than young less educated women. The need for concerted effort in campaigns and enlightenment programmes aimed at empowering women and making perpetrators of wife abuse realise why the act should be stopped was highlighted. " 1 results 1
- Abundance of weed species promotes biodiversity within agroecosystems whereas it constitutes biotic stress in arable farmland. There is insufficient information on effects of weed species composition and diversity’ on performance of upland rice in Nigeria. Therefore, a 2-year field study was conducted to assess the weed species composition, diversity and its effects on growth and yield of upland rice cultivars. A split-plot design was used with two rice cultivars (CGI4 and NERICA2) as the main plot treatment and four weeding regimes as the sub-plot. Weeds were sampled from each plot with a 0.5 m * 0.5 m wooden quadrat. The weed species were identified to species level, counted and recorded. Data collected were used to calculate relative frequency, relative density and relative importance value for each species. Dominance, Simpson, Shannon Wiener and evenness indices were used to describe the community structure. The flora of the study site varied widely in occurrence. Twenty four weed species comprising 16 annual herbs, four sedges, three grasses and one commelinaceae Family were found interfering with upland rice. The field had highly diversed annual, herbacious, dicotyledonous and monoc.tyledonous weed species native to tropical ecosystems. The upland rice field had evenly distributed rich and highly diversed weed community. Cultivar CGI4 performed significantly better than NERICA2 with respect to number of leaves (32.56) formed, tillering (8.67) and panicles (8.25) produced. The CG14 plot left unweeded throughout the study period had significantly highest weed biomass (6.16 t/ha) compared to NERICA2 plots. Absolute weed interefence reduced grain yield in NERICA2 and CGI4 cultivars by 42.7 % and 30.9 %, respectively. The biomass accumulated by weed species were inversely related to grain yield (t/ha) in both seasons. 1 results 1
- Acetylation 1 results 1
- Acid hydrolysis. 1 results 1
- Activated carbon, 1 results 1
- Adolescents 1 results 1
- Adsorption refrigeration technology has been intensively investigated in many countries of the world because of its potential for competing with conventional vapour compression refrigeration and its environmental friendliness. A solar-powered adsorption refrigerator using activated carbon/methanol pair was designed and fabricated. A mathematical model was developed based on the thermodynamics of the adsorption process, heat and mass transfer equations of the collector/generator/absorber components and simplified idealization of the condenser and evaporator components. The partial differential equations generated from the analysis were transformed into explicit finite difference forms for numerical solution. The model was used to compute the collector plate, bond and adsorbent temperatures, and the COP. The model was validated by using data from experiments performed on a solar powered activated carbon/methanol refrigerator and from published works. The predicted peak plate, tube and adsorbent temperatures were 102, 88 and 86°C respectively which compared favourably with 109 peak plate, 95 tube, and 85°C adsorbent temperatures from published works. The COP of the modelled refrigerator using imported activated carbon ranged from 0.0340 to 0.0345 compared to 0.0300 to 0.0550 recorded in the literature while the COP achieved from the experimental rig using locally manufactured activated carbon ranged from 0.0163 to 0.0200. Reducing the tube thickness from 5mm to 1.5mm led to a gain of 80.0% in COP. The adsorbent parking density of 550 kg/m3 gave an optimum COP, while a decrease of plate thickness from 1.5mm to 1.0mm increased the COP from 0.0338 to 0.0352. 1 results 1
- Adsorption, 1 results 1
- Asymptomatic malaria 1 results 1
- Background and Objectives: Asymptomatic malaria results from partial immunity resulting from recurrent exposure to the malaria parasite and it has been shown not to be benign as it was earlier believed. Adolescents are likely to have partial immunity to malaria which can predispose them to the asymptomatic form of malaria, but malaria is understudied in this age group. This study was conducted to compare the haematologic parameters among secondary school adolescents with and without asymptomatic malaria in Ibadan. Methods: A cross-sectional study was conducted and data regarding sociodemographic characteristics, presence or otherwise of malaria parasite (using microscopy) and haematological parameters (obtained using haematology auto- analyser and microscopy) were documented. Malaria parasite density was categorised as 1-100 and >100/μL. Other haematological parameters were classified as categorical variables. Associations were determined using Chi square test and level of significance was p<0.05. Results: A total of 103 students were recruited with a mean age of 15.6±2.02 years and 61(59.2%) were boys. Those from the low socioeconomic class were 86 (83.5%), 24 (23.3%) had asymptomatic malaria while 22 (21.4%) had parasite density of >100/μL. Haematological abnormalities detected were anaemia (11.7%), leucopenia (4.9%), thrombocytopenia (11.7%), reduced MCV and reduced MCH (88.3%). All participants had low MCHC. Abnormal peripheral blood film was found in 79.5% but this was not associated with the presence of malaria parasite. Older adolescence (age ≥ 15 years) was significantly associated with parasite density of>100/μL (p = 0.02) and a higher proportion of those from the low socioeconomic class had asymptomatic malaria (24.4% vs 17.6%). Conclusion: Although some haematologic parameters of the study participants were affected by asymptomatic malaria, there were other unexplained blood abnormalities. There is a need to address asymptomatic malaria among these adolescents and other causes of abnormal blood profile should be tackled. 1 results 1
- Background. Irvingia gabonensis kernel polymer has gained attention indrug delivery systems because ofits compatibility and degradation under natural and physiological conditions. Objectives. This study aimed toevaluate Irvingia gabonensis polymer asamatrix system for thecontrolled delivery of ibuprofen incomparison toxanthan gum and hydroxypropylmethylcellulose (HPMC). Materials and methods. Irvingia gabonensis polymer was extracted using established methods and dried using theoven- and freeze-drying methods. Ibuprofen tablets were prepared bydirect compression and theeffects ofpolymer concentration (10–50%), excipients (lactose, microcrystalline cellulose and dicalcium phosphate dihydrate) and polymers (xanthan gum and HPMC) onthemechanical and drug release proper¬ties ofthetablets were evaluated. Density measurements and theHeckel and Kawakita equations were used todetermine thecompression properties ofthetablets. Friability, crushing strength and thecrushing strength–friability ratio (CSFR) were used toevaluate themechanical properties ofthetablets, while dis¬solution times were used toevaluate drug release from thematrices. Thedrug release mechanisms were determined byfitting thedissolution data into classic kinetic equations. Results. Irvingia gabonensis polymer deformed plastically with afast onset and ahigh amount ofplastic deformation compared with xanthan gum and HPMC. This polymer was directly compressible and formed intact non-disintegrating tablets; themechanical and dissolution properties ofIrvingia gabonensis polymer tablets generally decreased with increasing concentration ofibuprofen. Theranking ofdissolution times was xanthan gum> freeze-dried Irvingia gabonensis> HPMC> oven-dried Irvingia gabonensis. Theaddition oftheexcipients improved themechanical properties ofthetablets, aided ibuprofen release, and altered therelease kinetics, which was largely defined bytheKorsmeyer–Peppas model. Increasing theproportion ofxanthan gum and HPMC inthematrices resulted inadecreased amount ofibuprofen released after 9h, with xanthan gum having agreater effect. Conclusions. Irvingia gabonensis polymer matrices may be effective inthepreparation ofcontrolled release tablets, and their right combination with xanthan gum orHPMC could provide atime-independent release for longer durations. 1 results 1
- Battery cage 1 results 1
- Blood cell morphology 1 results 1
- Ceiling board 1 results 1
- Chinese yam (Dioscorea oppositifolia) starch modified by acid hydrolysis was characterized and compared with native starch as a binder in chloroquine phosphate tablet formulations. The physicochemical and compressional properties (using density measurements and the Heckel and Kawakita equations) of modified Chinese yam starch were determined, and its quantitative effects as a binder on the mechanical and release properties of chloroquine phosphate were analyzed using a 23 full factorial design. The nature (X1), concentration of starch (X2) and packing fraction (X3) were taken as independent variables and the crushing strength–friability ratio (CSFR), disintegration time (DT) and dissolution time (t80) as dependent variables. Acid-modified Chinese yam starch showed a marked reduction (p<0.05) in amylose content and viscosity but increased swelling and water-binding properties. The modified starch had a faster onset and greater amount of plastic flow. Changing the binder from native to acid-modified form led to significant increases (p<0.05) in CSFR and DT but a decrease in t80. An increase in binder concentration and packing fraction gave similar results for CSFR and DT only. These results suggest that acid-modified Chinese yam starches may be useful as tablet binders when high bond strength and fast dissolution are required. 1 results 1
- Chinese yam/starch/binding properties 1 results 1
- Clinical trial 1 results 1
- Compression properties 1 results 1
- Controlled release 1 results 1
- Covariates 1 results 1
- Deep litter 1 results 1
- Development of empirical models provides ample prospects of exploring established mathematical theories and relationships among tree growth variables for sustainable forest management options. However, there is inadequate information on modelling growth characteristics and productivity potentials of Pinus caribaea, a pulpwood species which is now being proposed for timber production in Nigeria. Hence, models for growth characteristics and their applications in yield studies for Pinus caribaea in southwestern Nigeria were investigated. Sixty Temporary Sample Plots (TSPs) of size 20m x 20m each and of different Age (A) series based on stocking density were sampled from Omo Forest Reserve (n=16 TSPs -15 and 21 years), Oluwa Forest Reserve (n=36 TSPs-18, 20, 35, 36 and 37 years) and Shasha Forest Reserve (n=8TSPs-27years) in Ogun, Ondo and Osun States respectively using stratified random sampling method. Growth variables: Diameter at Breast Height (DBH), Stem Quality (SQ) and Total Height (THT) were measured in each plot and Basal Area (BA), Stem Volume (SV), Tree Slenderness Coefficient (TSC), Crown Ratio (CR), Crown Projection Area (CPA) and Site Index (SI) estimated. A total of 1,592 trees were enumerated and each tree per plot classified into four canopy layers as dominant, co-dominant, intermediate and suppressed. Data obtained were used for modelling and categorized into individual tree level, size class level and whole stand level with Maximum Likelihood Estimation (MLE) technique adopted in 3-parameter Weibull Probability Distribution Functions (WPDF). Data were analysed using descriptive statistics, ANOVA, correlation and regression analyses at α0.05. Growth variables exhibited significant variations among the canopy layers with the dominant canopy layer having the highest mean THT of 14.9±0.2m and intermediate canopy layer lowest with 7.8±0.1m. Stem volume (1.4±0.04m3) and BA (0.1±0.002m2) were also highest in the dominant canopy layer. Slenderness coefficient however was highest (80.6±1.1) within the suppressed canopy layer while crown ratio was highest (0.27±0.001) in intermediate canopy layer. There were positive relationships between the growth variables across the stands with coefficients of correlation (r) ranging from 0.01-0.98 for individual tree level and 0.41-0.91 for whole stand level. Similar results of UNIVERSITY OF IBADAN LIBRARY iii correlation between Weibull parameters and other growth variables at the size class level were significant with r ranging between -0.72 and 0.92 with location parameter „a‟ of the WPDF having the highest positive association of r = 0.92 with DBH. The growth-yield models were of the forms lnCR =-3.5507+0.6263lnTHT+0.1558CPA+10.2339A 1, R2 =0.98 for dominant layer, lnCR = -3.1922+0.6363CPA+7.6876A-1, R2 = 0.994 for intermediate layer, lnTHT= 0.4547+0.0032lnSQ+0.6757CPA+0.1052A-1, R2=0.989 for suppressed layer and lnTHT=0.5872+0.5348CPA+0.0567A-1 with R2= 0.996 for co-dominant layer respectively. The overall best model among individual, size and whole stand categories was found within the whole stand level with R2=0.999 and of exponential form: lnSV=-0.7759+0.0001SI+0.0005A-1 +0.9532lnBA. The best adjudged growth-yield model among the canopy layers was found within the co-dominant layer. The selected whole stand growth-yield model was suitable for both current and future prediction of major growth characteristics and productivity potentials of Pinus caribaea in southwestern Nigeria. Keywords: Pinus caribaea, Growth variables, Yield models, Tree canopy layers Word count: 489 1 results 1
- Dioscorea oppositifolia 1 results 1
- Drugs/release 1 results 1
- Egg storage quality 1 results 1
- Fibre reinforcement 1 results 1
- Growth variables 1 results 1
- Haematology profile 1 results 1
- Hen day egg production 1 results 1
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