317 research outputs found
THE EFFECT OF STEREOTYPE ON COGNITIVE PERFORMANCE: AN EXPERIMENTAL STUDY OF FEMALE COGNITIVE PERFORMANCE
This study investigated the effect stereotypes have on cognitive performance. A between-subjects experimental design was utilized in the study. Forty participants from the senior secondary two (SS2) of Chapel Secondary School Ilorin took part in the study, and their cognitive performance in the light of exposure to a stereotype was
measured. Four hypotheses were tested. Using the t-test for
independent samples, the findings of the experiment showed that males performed better than females on a mathematics test when exposed to stereotype (t=2.688, df=l8, p<O.OS). The study also found that males who were exposed to stereotype performed better than males who were not exposed to stereotype (t=2.998, df=l8, p< 0.05).
However, there was no significant difference in the performance of females who were exposed to stereotype and those who were not (t=2.740, df=l8, p>O.OS). Stereotypes have been identified to affect the way people see things and the way they interpret certain behaviours of
other individuals or groups. Therefore understanding the nature of stereotypes, prejudice, and discrimination is the first step in combating these practices
Optimal Structural Results for Assemble-to-Order Generalized M-Systmes
Cataloged from PDF version of article.We consider an assemble-to-order generalized M-system with multiple components and multiple products,
batch ordering of components, random lead times, and lost sales. We model the system as an in nite-horizon
Markov decision process and seek an optimal control policy, which speci es when a batch of components
should be produced and whether an arriving demand for each product should be satis ed. To facilitate
our analysis, we introduce new functional characterizations for convexity and submodularity with respect to
certain non-unitary directions. These help us characterize optimal inventory replenishment and allocation
policies under a mild condition on component batch sizes via a new type of policy: lattice-dependent base-stock
and lattice-dependent rationing
Chronic Wounds in Children: Prevalence, Aetiological Types and Predilection Sites in a Rural Setting in an Emerging Economy
The aim of this study was to determine the prevalence, aetiological types and predilection sites of chronic wounds in children. This study was a cross sectional study conducted on children aged 0-15 years. Through cluster sampling technique, children with wounds were recruited and evaluated. Demographic and clinical data were collected and analyzed. Descriptive statistics were used to summarize variables and Chi-squared test was used to achieve comparison between age groups and sexes. Statistical significance was defined as p<0.05. The results show that one thousand and ten children were screened for wounds out of which 107 children with 115 wounds were found. 16.5% of these wounds were chronic with a prevalence rate of 2.0%. Chronic wound prevalences in the school aged (47.4%) and adolescent (52.6%) children were 0.9% and 1.0% respectively (x2 = 0.821; p = 0.359 Yates’ corrected, Fisher’s exact test 2-sided) and statistically insignificant. 57.9% were caused by trauma and majority (89.5%) occurred in the lower limbs (x2=0.000; p=1.000 Yates’ corrected, Fisher’s exact test 2-sided) without any statistical significance. Prevalence of chronic wounds in the children population was very low. The commonest aetiological type was inadequately treated traumatic wounds which progressively healed on institution of appropriate wound treatment
Microbial Spectrum and Antibiogram of Non-surgical Wounds in Children in a Rural Setting in Nigeria
The aim of this study was to determine the microbial spectrum and susceptibility pattern of non-surgical wound infections in children in a rural setting in our environment. This study was a cross sectional study of children aged 0 to 15 years in Bakassi, Nigeria. The children were screened for non-surgical wounds using an interviewer administered semi-structured questionnaire. Identified wounds were evaluated clinically for signs of infection and specimens were collected and cultured using standard microbiologic techniques. Susceptibility test was performed on all the isolated Micro-organisms. Data were collected and analysed using SPSS version 20 for windows. Sixty four wound infections out of a total of 115 wounds giving an infection rate of 55.7% were encountered. Of 64 wound cultures, 46.9% (30/64,) yielded mono-microbial growth, while poly-microbial growth of two and three microorganisms were obtained in 46.9% (30/64) and 1.6% (1/64) specimens respectively.A total of 92 organisms were isolated belonging to seven different species. Staphylococcus aureus (n= 57/92, 62.0%) and Streptococcus pyogenes (n = 30/92, 32.6%) were the predominant pathogens isolated. High rate of community acquired Methicillin Resistant Staphylococcus aureus (MRSA) (38/57, 66.7%) was observed. The microbial spectrum of non-surgical wounds of children in rural communities is wide. The high rate of antimicrobial resistance particularly MRSA and high predominance of S. pyogenes are potential sources of dire consequence in management and long term morbidity
Experimental Results Indicating Lattice-Dependent Policies May Be Optimal for General Assemble-To-Order Systems
We consider an assemble-to-order (ATO) system with multiple products, multiple components which may be demanded in different quantities by different products, possible batch ordering of components, random lead times, and lost sales. We model the system as an infinite-horizon Markov decision process under the average cost criterion. A control policy specifies when a batch of components should be produced, and whether an arriving demand for each product should be satisfied. Previous work has shown that a lattice-dependent base-stock and lattice-dependent rationing (LBLR) policy is an optimal stationary policy for a special case of the ATO model presented here (the generalized M-system). In this study, we conduct numerical experiments to evaluate the use of an LBLR policy for our general ATO model as a heuristic, comparing it to two other heuristics from the literature: a state-dependent base-stock and state-dependent rationing (SBSR) policy, and a fixed base-stock and fixed rationing (FBFR) policy. Remarkably, LBLR yields the globally optimal cost in each of more than 22,500 instances of the general problem, outperforming SBSR and FBFR with respect to both objective value (by up to 2.6% and 4.8%, respectively) and computation time (by up to three orders and one order of magnitude, respectively) in 350 of these instances (those on which we compare the heuristics). LBLR and SBSR perform significantly better than FBFR when replenishment batch sizes imperfectly match the component requirements of the most valuable or most highly demanded product. In addition, LBLR substantially outperforms SBSR if it is crucial to hold a significant amount of inventory that must be rationed. © 2015 Production and Operations Management Society
Geochemical Speciation and Risk Assessment of Trace Metals in Sediments from Coastal Ecosystems off Equatorial Atlantic Ocean
The concentrations of Cd, Cr, Cu, Ni and Pb in estuarine benthic sediments were determined through multistep speciation scheme to evaluate their spatio-temporal distributions, selective fraction magnitude, degree of contamination and potential ecological risks. The results indicated that the metal fractionation percentages in the residual, oxidizable and reducible fractions are the most significant, while the exchangeable and carbonates bound trace metals are relatively low. High mobility and bioavailability was indicated for Cu, Cr and Ni, while Cd and Pb in sediments present low bioavailability for biota. Contamination factor (CFm), degree of contamination (DC), modified degree of contamination (mCd), geoaccumulation index (Igeo), risk assessment code (RAC), and potential ecological risk index (PERI) were used to assess trace metals sedimentary pollution. The results indicate a prevalent moderate to high contamination of most trace metals analyzed. The contamination ranking of trace metals based on percent contribution to DC was Cd>Pb>Cu>Cr>Ni. RAC values indicate medium risk for Cd and Ni at all studied sites during the wet and dry seasons. Cd and Pb show moderate and very high individual metal potential ecological risk, respectively, while multi-elemental potential ecological risk indices (RIs) indicate very high ecological risk in all the ecosystem
New ecological risk indices for evaluating heavy metals contamination in aquatic sediment: A case study of the Gulf of Guinea
New indices – modified hazard quotient (m HQ) and ecological contamination index (ECI) – were
developed for the evaluation of heavy metals contamination of sediment. Sequential extraction method
was employed to determine the levels of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead
(Pb) in subtidal sediment samples from tropical ecosystems off the Gulf of Guinea. The results were used
to assess the degree of contamination and estimate the extent of anthropogenic inputs from industrial
activities. Results indicated that the concentrations of Cd, Cr, Cu, Ni and Pb ranged from 4.33 –5.67, 11.12–
28.52, 30.26–43.72, 2.02–2.60 and 162.0–190.37 mg/kg dw, respectively. The mean metal levels did not
show significant variations among study sites during the wet and dry seasons. Spatial distribution and
severity of sediment-associated contamination by heavy metals based on the newly developed indices
(m HQ and ECI) were in good agreement with existing pollution indices and followed the descending
sequence: Cd>Pb>Cu>Cr>Ni. Contamination severity index, mean hazard quotient and modified risk
assessment code were also used to evaluate the sediment-heavy metal contamination, which generally
indicated medium risk contamination of the investigated ecosystems. Aquatic pollution indicators (potential
contamination index, ECI, hazard quotients, m HQ) revealed significant anthropogenic contamination
by Cd and Pb, while Cr, Cu and Ni showed relatively low degree of contamination. Potential contamination
index (PCI) generally followed the sequence Cd>Pb>Cu>Cr>Ni. A comparison of newly proposed indices
with existing pollution indices revealed very good agreement. The contamination trends derived from
the new indices were consistent and took into consideration site specificity, toxicity and a three-tier
effect levels (threshold, mid-range and extreme effects guideline values) that support their reliability in
evaluating contaminated aquatic ecosystems
Health Risk Assessment for Exposure to Some Selected Heavy Metals via Drinking Water from Dadinkowa Dam and River Gombe Abba in Gombe State, Northeast Nigeria
Abstract The concentrations of eight heavy metals (Fe, Mn, Cu, Pb, Cd, Ni, Co and Zn) were determined by atomic absorption spectroscopy in water from Dadinkowa dam and Kwadon boreholes which are the major sources of drinking water to Gombe town in Gombe State, North-East, Nigeria. The concentrations of metals in water from Dadinkowa dam were in the order: Fe (1.86mg/l), Mn(0.68mg/l), Cu(0.92mg/l), Pb(0.19mg/l), Cd(0.50mg/l), Ni(0.59mg/l), Co(0.42mg/l) and Zn(0.83mg/l).The concentrations of the metals in water from Gombe Abba River were in the order Fe(0.21 mg/l), Mn (0.24 mg/l), Cu (0.29 mg/l), Pb (0.02 mg/l), Cd (0.10 mg/l), Ni( 0.04 mg/l), Co(0.12 mg/l) and Zn (0.41 mg/l). The human health risk assessment was performed by determining the chronic daily intake (CDI), hazard quotient (HQ) and total hazard index (THI) of the metals through human oral consumption for both adults and children. The HQ of iron, manganese, nickel and cobalt in water from Dadinkowa dam were all greater than unity and thus pose a potential health risk for both adults and children while cobalt was the only heavy metal of concern in water from Gombe Abba River as its HQ was greater than unity. The THI of water from all the sampled sites assessed were of high risk. Further monitoring of these sites is recommended as well as research by biomedical experts to reveal the exact adverse effects that heavy metal contamination of water might induce in humans, particularly among individuals in vulnerable populations such as children
Dietary elimination of children with food protein induced gastrointestinal allergy – micronutrient adequacy with and without a hypoallergenic formula?
Background:
The cornerstone for management of Food protein-induced gastrointestinal allergy (FPGIA) is dietary exclusion; however the micronutrient intake of this population has been poorly studied. We set out to determine the dietary intake of children on an elimination diet for this food allergy and hypothesised that the type of elimination diet and the presence of a hypoallergenic formula (HF) significantly impacts on micronutrient intake.
Method:
A prospective observational study was conducted on children diagnosed with FPIGA on an exclusion diet who completed a 3 day semi-quantitative food diary 4 weeks after commencing the diet. Nutritional intake where HF was used was compared to those without HF, with or without a vitamin and mineral supplement (VMS).
Results:
One-hundred-and-five food diaries were included in the data analysis: 70 boys (66.7%) with median age of 21.8 months [IQR: 10 - 67.7]. Fifty-three children (50.5%) consumed a HF and the volume of consumption was correlated to micronutrient intake. Significantly (p <0.05) more children reached their micronutrient requirements if a HF was consumed. In those without a HF, some continued not to achieve requirements in particular for vitamin D and zinc, in spite of VMS.
Conclusion:
This study points towards the important micronutrient contribution of a HF in children with FPIGA. Children, who are not on a HF and without a VMS, are at increased risk of low intakes in particular vitamin D and zinc. Further studies need to be performed, to assess whether dietary intake translates into actual biological deficiencies
Review
Previous surgical procedures devised for intractable pain are the excision of painful area of the skin, peripheral neurotomy, intraspinal or intracranial posterior rhizotomies, anterolateral spinal cordotomy, spinothalamic tractotomy at medulla and mesencephalon for the pain of organic origin, and the prefrontal lobotomy for psychogenic pain. Unfortunately, these procedures are followed either by disturbance of physiologic sensory function or by changes of affect and personality. Partial gasserian gangliolysis successfully alleviated the trigeminal neuralgia without significant sensory disturbance of the face. Recent advances in stereotaxic technique has enabled us to attack the thalamus and other deep subcortical centers. This new method, together with recent neuroanatomico-physiological progress in regard to pain tract through intralaminar nuclear complex, resulted in discovery of thalamotomy destroying the nucleus centrum medianum with or without adjacent intralaminar nuclei, which eliminates the organic pain without any detectable sensory deficit. Anterior cingulectomy or cingulumotomy has developed to alleviate the psychogenic pain without psychological changes. These are the ideal pain-relieving procedures. A new method of percutaneous cervical cordotomy can be safely used for the debilitated patients with terminal malignant diseases
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