An Improved Location Model for the Collection of Sorted Solid Waste in Densely Populated Urban Centres

This paper presents a facility location model for improving the collection of solid waste materials. The model is especially suitable for densely populated regions with several housing units as well as encourages initial sorting of wastes. Each individual house in the collection area is designated a customer, with randomly selected customers comprising the set of candidate hubs. The fundamental feature of the model is to group the customers into clusters by assigning each customer (house) to the nearest hub. Each cluster is then assigned to exactly one waste collection site drawn from the set of potential collection locations. The objective is to minimize the total number of activated waste collection sites such that all the customers’ requests are satisfied without violating the capacity limit of each site. A simple Lagrangian relaxation heuristic is developed for the problem and solved with the CPLEX solver on the AMPL platform to find a feasible solution. Results from the numerical implementation of model show the model is efficient and competitive with existing solid waste collection facility location model

OPTIMISATION OF LYE-PEELING OF CASSAVA (Manihot esculenta Crantz) USING RESPONSE SURFACE METHODOLOGY

Cassava (Manihot esculenta Crantz) is an important root crop in many tropical developing countries. Conventional peeling, done manually using knives is wasteful and unsuitable for industrial scale operation. Optimum condition for the peeling of cassava by immersion in hot lye (NaOH) solution was determined using Response Surface Methodology (RSM) for pre-determined three levels of Peeling Efficiency Index (PEI). Some cassava was peeled manually and some with hot lye solution. The effects of lye–concentration (4-12%), immersion temperature (75-100°C) and immersion time (2.5-10min.) on PEI (removal of 11-15% of root) obtained from 23 experimental points and three replication were analyzed with design expert and statistical analysis system software. Complete lye–peeling (removal of 11% of the root) was achieved at 9.7%, 86°C and 5min respectively which were within the critical optimization range (R2=43%, CV=44% and root mean square error 0.3935) generated by the RSM

OPTIMIZATION OF LYE PEELING OF BREADFRUIT (Artocarpus comminis Frost) USING RESPONSE SURFACE METHODOLOGY

Breadfruit (Artocarpus communis  Frost) is an important food crop in many tropical developing coun-        tries. Conventional peeling, done manually using knives is wasteful and unsuitable for industrial scale        operation. Optimum condition for the peeling of breadfruit by immersion in hot lye (NaOH) solution was        determined using Response Surface methodology (RSM) for pre-determined three levels of Peeling        Efficiency Index   (PEI). Some   breadfruit   was   peeled   manually   and   some   with   hot lye   solution.   The        effects of lye–concentration (0.5-2.0%), immersion temperature (70-90°C) and immersion time (2.5-        10min.) on PEI (removal of 6-11% of peel) with subsequent soft and abrasive washing of the peeled        crop obtained from 14 experimental points and three replication were analyzed with design expert and        statistical analysis system software. Complete lye–peeling (removal of 6% of the fruit ) was achieved                                                                                                   2        at   1.6%,   80°C   and   5min   respectively   which   were   within   the   critical   optimization   range   (R =52%,        CV=75.9%) generated by the RSM.&nbsp

Hemangiomatous ameloblastoma: report of a case

Hemangiomatous ameloblastoma is a rare variant of ameloblastoma with only a few cases reported in the English literature. This is a report of a 42 year old man with a recurrent mandibular neoplasm who had r epeated surgical interventions. Clinical and radiographic examinations were not significantly different from other regular variants of ameloblastoma. Microscopic examination however revealed islands of cuboidal and columnar cells arranged in a pallisaded pattern with a central area of squamous metaplasia and stellate reticulum-like cells. There were multiple vascular channels containing red blood cells within the stellate reticulum-like areas. Surgical resection of the mandibular mass was done with immediate reconstruction. It may be concluded that repeated surgical interventions may be a possible etiology for the development of hemangiomatous ameleblastoma

Trends of oral cancer in University College Hospital, Ibadan, Nigeria

Objective: The aim of this study was to describe the trend and recent pattern of oral cancer in the University College Hospital, Ibadan, Nigeria. Method: A retrospective analysis of all cases of oral cancer (excluding lymphoid cancers) documented in the records of the Departments of Oral and Maxillofacial Surgery and Pathology, University College Hospital (UCH), Ibadan, from the year 1983 to 2007 was done. The analysis of the data collected was compared with three earlier studies in this same centre and the published literature in general. Result: Over the 25-year-period a total 450 cases of oral cancer were recorded. More than half of the cases were squamous cell carcinomas (SCC) and 58.0% of these occurred in the palate which was the commonest site. Compared with previous studies, the male to female ratio of 1.4:1 revealed a higher number of females, and more patients were recorded in the first and tenth decades of life. Conclusion: The trends in oral cancer prevalence in UCH, Ibadan, show that oral SCC, still occurs commonly in the palate in our environment, and constituted the bulk of oral cancer. In addition, more females and patients within the extremes of age are being increasingly affected. There is before a need for more investigations into the possible aetiological factors in our environment in order to offer a preventive approach to the management of the disease

Artificial Sweeteners Disrupt Tight Junctions and Barrier Function in the Intestinal Epithelium through Activation of the Sweet Taste Receptor, T1R3

The breakdown of the intestinal epithelial barrier and subsequent increase in intestinal permeability can lead to systemic inflammatory diseases and multiple-organ failure. Nutrition impacts the intestinal barrier, with dietary components such as gluten increasing permeability. Artificial sweeteners are increasingly consumed by the general public in a range of foods and drinks. The sweet taste receptor (T1R3) is activated by artificial sweeteners and has been identified in the intestine to play a role in incretin release and glucose transport; however, T1R3 has not been previously linked to intestinal permeability. Here, the intestinal epithelial cell line, Caco-2, was used to study the effect of commonly-consumed artificial sweeteners, sucralose, aspartame and saccharin, on permeability. At high concentrations, aspartame and saccharin were found to induce apoptosis and cell death in intestinal epithelial cells, while at low concentrations, sucralose and aspartame increased epithelial barrier permeability and down-regulated claudin 3 at the cell surface. T1R3 knockdown was found to attenuate these effects of artificial sweeteners. Aspartame induced reactive oxygen species (ROS) production to cause permeability and claudin 3 internalization, while sweetener-induced permeability and oxidative stress was rescued by the overexpression of claudin 3. Taken together, our findings demonstrate that the artificial sweeteners sucralose, aspartame, and saccharin exert a range of negative effects on the intestinal epithelium through the sweet taste receptor T1R3

Community-based infant hearing screening in a developing country: parental uptake of follow-up services

<p>Abstract</p> <p>Background</p> <p>Universal newborn hearing screening is now considered an essential public health care for the early detection of disabling life-long childhood hearing impairment globally. However, like any health interventions in early childhood, parental support and participation is essential for achieving satisfactory uptake of services. This study set out to determine maternal/infant socio-demographic factors associated with follow-up compliance in community-based infant hearing screening programmes in a developing country.</p> <p>Methods</p> <p>After health educational/counselling sessions, infants attending routine childhood immunisation clinics at four primary care centres were enrolled into a two-stage infant hearing screening programme consisting of a first-stage screening with transient-evoked otoacoustic emissions and second-stage screening with automated auditory brainstem response. Infants referred after the second-stage screening were scheduled for diagnostic evaluation within three months. Maternal and infant factors associated with completion of the hearing screening protocol were determined with multivariable logistic regression analysis.</p> <p>Results</p> <p>No mother declined participation during the study period. A total of 285 out of 2,003 eligible infants were referred after the first-stage screening out of which 148 (51.9%) did not return for the second-stage, while 32 (39.0%) of the 82 infants scheduled for diagnostic evaluation defaulted. Mothers who delivered outside hospitals were significantly more likely to return for follow-up screening than those who delivered in hospitals (Odds ratio: 1.62; 95% confidence intervals: 0.98 – 2.70; p = 0.062). No other factors correlated with follow-up compliance for screening and diagnostic services.</p> <p>Conclusion</p> <p>Place of delivery was the only factor that correlated albeit marginally with infant hearing screening compliance in this population. The likely influence of issues such as the number of return visits for follow-up services, ineffective tracking system and the prevailing unfavourable cultural perception towards childhood deafness on non-compliance independently or through these factors warrant further investigation.</p

Causes And Effect Of Delay On Project Construction Delivery Time

Delay is one of the biggest problems often experienced on construction project sites. Delays can instigates negative effects such as increased costs, loss of productivity and revenue many lawsuits between owners and contractors and contract termination. The aim of this project is to investigate the causes and effects of delay on building construction project delivery time. Random sampling technique was used in this study. Population sample of 150 was used in this work. A total sample of ninety three (93) was deployed. A structured questionnaire in Likert scale was used in data collection. There are many factors that induce delay on construction projects, however in some of identified factors includes: lack of funds to finance the project to completion, changes in drawings, lack of effective communication among the parties involved , lack of adequate information from consultants, slow decision making and contractor’s insolvency, variations among others. Also, project management problem, mistake and discrepancies in contract document, equipment availability and failure, mistakes during construction, bad weather, fluctuation in prices of building materials, inappropriate overall organizational structure linking to the project and labour. The factors above could be observed and could be a clue to preventing delay on construction sites