Search results for: square tubes

Authors: Isadora Bugarin, Taygoara F. de Oliveira

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Binary fluids and emulsions, in general, are present in a vast range of industrial, medical, and scientific applications, showing complex behaviors responsible for defining the flow dynamics and the system operation. However, the literature describing those highlighted fluids in non-isothermal models is currently still limited. The present work brings a detailed investigation on droplet migration due to natural convection in square enclosure, aiming to clarify the effects of drop viscosity on the flow dynamics by showing how distinct viscosity ratios (droplet/ambient fluid) influence the drop motion and the final movement pattern kept on stationary regimes. The analysis was taken by observing distinct combinations of Rayleigh number, drop initial position, and viscosity ratios. The Navier-Stokes and Energy equations were solved considering the Boussinesq approximation in a laminar flow using the finite differences method combined with the Level Set method for binary flow solution. Previous results collected by the authors showed that the Rayleigh number and the drop initial position affect drastically the motion pattern of the droplet. For Ra ≥ 10⁴, two very marked behaviors were observed accordingly with the initial position: the drop can travel either a helical path towards the center or a cyclic circular path resulting in a closed cycle on the stationary regime. The variation of viscosity ratio showed a significant alteration of pattern, exposing a large influence on the droplet path, capable of modifying the flow’s behavior. Analyses on viscosity effects on the flow’s unsteady Nusselt number were also performed. Among the relevant contributions proposed in this work is the potential use of the flow initial conditions as a mechanism to control the droplet migration inside the enclosure.

Keywords: binary fluids, droplet motion, level set method, natural convection, viscosity

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Authors: Uchenna Cosmas Ugwu, Osmond Chukwuemeka Ene

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Globally, older adults are considered the most vulnerable groups to age-related diseases including diabetes mellitus, obesity, cardiovascular diseases, cancer and osteoporosis. With improved access to quality healthcare services, these complications can be prevented and the incidence rates reduced to the least occurrence. The aim of this study is to validate appropriate measures for improving quality healthcare services utilization among elderly persons in Nigeria and also to determine the significant association within demographic variables. A cross-sectional survey research design was adopted. Using a convenient sampling technique, a total of 400 experts (150 registered nurses and 250 public health professionals) with minimum of doctoral degree qualification were sampled and studied. A structured instrument titled “Expert-Based Healthcare Services Utilization Questionnaire (EBHSUQ) with .83 reliability index was used for data collection. All the statistical data analysis was completed using frequency counts, percentage scores and chi-square statistics. The results were significant at p≤0.05. It was found that quality healthcare services utilization by elderly persons in Nigeria would be improved if the services are: available (83%), affordable (82%), accessible (79%), suitable (77%), acceptable (77%), continuous (75%) and stress-free (75%). Statistically, significant association existed on quality healthcare services utilization with gender (p=.03<.05) and age (p=.01<.05) while none was observed on work experience (p=.23>.05), marital status (p=.11>.05) and employment category (p=.09>.05). To improve quality healthcare services utilization for elderly persons in Nigeria, the adoption of appropriate measures by Nigerian government and professionals in healthcare sectors are paramount. Therefore, there is need for collaborative efforts by the Nigerian government and healthcare professionals geared towards educating the general public through mass sensitization, awareness campaign, conferences, seminars and workshops for the importance of accessing healthcare services.

Keywords: elderly persons, healthcare services, cross-sectional survey research design, utilization.

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Authors: P. V. Pramila , V. Mahesh

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Pulmonary Function Tests are important non-invasive diagnostic tests to assess respiratory impairments and provides quantifiable measures of lung function. Spirometry is the most frequently used measure of lung function and plays an essential role in the diagnosis and management of pulmonary diseases. However, the test requires considerable patient effort and cooperation, markedly related to the age of patients esulting in incomplete data sets. This paper presents, a nonlinear model built using Multivariate adaptive regression splines and Random forest regression model to predict the missing spirometric features. Random forest based feature selection is used to enhance both the generalization capability and the model interpretability. In the present study, flow-volume data are recorded for N= 198 subjects. The ranked order of feature importance index calculated by the random forests model shows that the spirometric features FVC, FEF 25, PEF,FEF 25-75, FEF50, and the demographic parameter height are the important descriptors. A comparison of performance assessment of both models prove that, the prediction ability of MARS with the `top two ranked features namely the FVC and FEF 25 is higher, yielding a model fit of R2= 0.96 and R2= 0.99 for normal and abnormal subjects. The Root Mean Square Error analysis of the RF model and the MARS model also shows that the latter is capable of predicting the missing values of FEV1 with a notably lower error value of 0.0191 (normal subjects) and 0.0106 (abnormal subjects). It is concluded that combining feature selection with a prediction model provides a minimum subset of predominant features to train the model, yielding better prediction performance. This analysis can assist clinicians with a intelligence support system in the medical diagnosis and improvement of clinical care.

Keywords: FEV, multivariate adaptive regression splines pulmonary function test, random forest

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Authors: Ayodeji Motunrayo Omoare

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Economically fish provides an important source of food and income for both men and women especially many households in the developing world and fishing has an important social and cultural position in river-rine communities. However, fish is highly susceptible to deterioration. Consequently, this study was carried out to correlate income generation of small-scale women fish processors in Abeokuta metropolis, Ogun State, Nigeria. Eighty small-scale women fish processors were randomly selected from five communities as the sample size for this study. Collected data were analyzed using both descriptive and inferential statistics. The results showed that the mean age of the respondents was 31.75 years with average household size of 4 people while 47.5% of the respondents had primary education. Most (86.3%) of the respondents were married and had spent more than 11 years in fish processing. The respondents were predominantly Yoruba tribe (91.2%). Majority (71.3%) of the respondents used traditional kiln for processing their fish while 23.7% of the respondents used hot vegetable oil to fry their fish. Also, the result revealed that respondents sourced capital from Personal Savings (48.8%), Cooperatives (27.5%), Friends and Family (17.5%) and Microfinance Banks (6.2%) for fish processing activities. The respondents generated an average income of ₦7,000.00 from roasted fish, ₦3,500.00 from dried fish, and ₦5,200.00 from fried fish daily. However, inadequate processing equipment (95.0%), non-availability of credit facility from microfinance banks (85.0%), poor electricity supply (77.5%), inadequate extension service support (70.0%), and fuel scarcity (68.7%) were major constraints to fish processing in the study area. Results of chi-square analysis showed that there was a significant relationship between personal characteristics (χ2 = 36.83, df = 9), processing methods (χ2 = 15.88, df = 3) and income generated at p < 0.05 level of significance. It can be concluded that significant relationship existed between processing methods and income generated. The study, therefore, recommends that modern processing equipment should be made available to the respondents at a subsidized price by the agro-allied companies.

Keywords: correlates, income, fish processors, women, small-scale

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Authors: Amna Imtiaz

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Aims: To correlate serum ferritin with left ventricular function in beta thalassemia major patients with increased transfusion dependence and to find out whether echocardiography can be used to assess pre clinical cardiac disease in these patients. Methods: The cross sectional study was conducted at Department of Pathology, Shaheed Zulfiqar Ali Bhutto Medical University, Pakistan Institute of Medical Sciences, Islamabad. 60 patients of beta thalassemia major with increased transfusion dependence were enrolled in this study. Serum ferritin levels of all patients were measured by using indirect enzyme linked immunosorbent assay (ELISA). Echocardiography was performed on all patients by a consultant cardiologist by linking conventional echocardiography with tissue Doppler imaging. Ejection fraction and E/A ratio were measured in all patients to assess left ventricular systolic and diastolic function. Results: On the basis of serum ferritin level, patients were divided into three groups. Group I consisted of patients having serum ferritin level equal to or less than 2500 ng/ml. A total of 25 patients were placed in this group. Group II included patients having serum ferritin level between 2500 to 5000 ng/ml. A total of 22 patients were placed in this group. Group III included patients having serum ferritin level more than 5000 ng/ml. This group consisted of 13 patients. All patients having serum ferritin below 2500ng/ml had normal systolic function, and only 16% of the patients in this group had diastolic dysfunction as reflected by abnormal E/A ratio. In group II, 27% of the patients had systolic dysfunction reflected by subnormal ejection fraction while 40% of the patients had diastolic dysfunction. In group III, 62% of the patients had abnormal systolic and diastolic function. Pearson correlation was used to find a correlation between serum ferritin and left ventricular function. A strong negative correlation was found which is reflected by a p value of less than 0.05 which is significant. Chi square test is used to correlate serum ferritin with E/A ratio. P value came out to be less than 0.05 which is significant.

Keywords: beta thalassemia major, left ventricular function, serum ferritin, transfusion dependence

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Authors: Chia-Jung Chen, Yu-Chi Hsu, June-Dong Lin, Kun-Chen Chan, Chieh-Tien Wang, Li-Ching Wu, Chung-Feng Liu

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With fast advances in healthcare technology, various total laboratory automation (TLA) processes have been proposed. However, adopting TLA needs quite high funding. This study explores an early adoption experience by Taiwan’s large-scale hospital group, the Chimei Hospital Group (CMG), which owns three branch hospitals (Yongkang, Liouying and Chiali, in order by service scale), based on the five stages of Everett Rogers’ Diffusion Decision Process. 1.Knowledge stage: Over the years, two weaknesses exists in laboratory department of CMG: 1) only a few examination categories (e.g., sugar testing and HbA1c) can now be completed and reported within a day during an outpatient clinical visit; 2) the Yongkang Hospital laboratory space is dispersed across three buildings, resulting in duplicated investment in analysis instruments and inconvenient artificial specimen transportation. Thus, the senior management of the department raised a crucial question, was it time to process the redesign of the laboratory department? 2.Persuasion stage: At the end of 2013, Yongkang Hospital’s new building and restructuring project created a great opportunity for the redesign of the laboratory department. However, not all laboratory colleagues had the consensus for change. Thus, the top managers arranged a series of benchmark visits to stimulate colleagues into being aware of and accepting TLA. Later, the director of the department proposed a formal report to the top management of CMG with the results of the benchmark visits, preliminary feasibility analysis, potential benefits and so on. 3.Decision stage: This TLA suggestion was well-supported by the top management of CMG and, finally, they made a decision to carry out the project with an instrument-leasing strategy. After the announcement of a request for proposal and several vendor briefings, CMG confirmed their laboratory automation architecture and finally completed the contracts. At the same time, a cross-department project team was formed and the laboratory department assigned a section leader to the National Taiwan University Hospital for one month of relevant training. 4.Implementation stage: During the implementation, the project team called for regular meetings to review the results of the operations and to offer an immediate response to the adjustment. The main project tasks included: 1) completion of the preparatory work for beginning the automation procedures; 2) ensuring information security and privacy protection; 3) formulating automated examination process protocols; 4) evaluating the performance of new instruments and the instrument connectivity; 5)ensuring good integration with hospital information systems (HIS)/laboratory information systems (LIS); and 6) ensuring continued compliance with ISO 15189 certification. 5.Confirmation stage: In short, the core process changes include: 1) cancellation of signature seals on the specimen tubes; 2) transfer of daily examination reports to a data warehouse; 3) routine pre-admission blood drawing and formal inpatient morning blood drawing can be incorporated into an automatically-prepared tube mechanism. The study summarizes below the continuous improvement orientations: (1) Flexible reference range set-up for new instruments in LIS. (2) Restructure of the specimen category. (3) Continuous review and improvements to the examination process. (4) Whether installing the tube (specimen) delivery tracks need further evaluation.

Keywords: innovation decision process, total laboratory automation, health care

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Authors: M. Varin, A. M. Dubois, R. Gadbois-Langevin, B. Chalghaf

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Good knowledge of the physical environment is essential for an integrated forest planning. This information enables better forecasting of operating costs, determination of cutting volumes, and preservation of ecologically sensitive areas. The use of satellite images in stereoscopic pairs gives the capacity to generate high precision 3D models, which are scale-adapted for harvesting operations. These models could represent an alternative to 3D LiDAR data, thanks to their advantageous cost of acquisition. The objective of the study was to assess the quality of stereo-derived canopy height models (CHM) in comparison to a traditional LiDAR CHM and ground tree-height samples. Two study sites harboring two different forest stand types (broadleaf and conifer) were analyzed using stereo pairs and tri-stereo images from the WorldView-3 satellite to calculate CHM. Acquisition of multispectral images from an Unmanned Aerial Vehicle (UAV) was also realized on a smaller part of the broadleaf study site. Different algorithms using two softwares (PCI Geomatica and Correlator3D) with various spatial resolutions and band selections were tested to select the 3D modeling technique, which offered the best performance when compared with LiDAR. In the conifer study site, the CHM produced with Corelator3D using only the 50-cm resolution panchromatic band was the one with the smallest Root-mean-square deviation (RMSE: 1.31 m). In the broadleaf study site, the tri-stereo model provided slightly better performance, with an RMSE of 1.2 m. The tri-stereo model was also compared to the UAV, which resulted in an RMSE of 1.3 m. At individual tree level, when ground samples were compared to satellite, lidar, and UAV CHM, RMSE were 2.8, 2.0, and 2.0 m, respectively. Advanced analysis was done for all of these cases, and it has been noted that RMSE is reduced when the canopy cover is higher when shadow and slopes are lower and when clouds are distant from the analyzed site.

Keywords: very high spatial resolution, satellite imagery, WorlView-3, canopy height models, CHM, LiDAR, unmanned aerial vehicle, UAV

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Authors: May Al Sahib

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This paper draws together an analysis of two autobiographical writings; Ahdaf Soueif’s Cairo: My City, Our Revolution (2012), Radwa Ashour’s Heavier than Radwa (2013), and Revolution is My Name: An Egyptian Woman’s Diary from Eighteen Days in Tahrir (2015). Soueif, Ashour, and Prince are Egyptian authors, activists, and cultural commentators who are fully aware that being a ‘third world’ citizen constrains the writer into taking a specific pattern in writing. However, this paper will analyze the choice of literary form in writing the 2011 January revolution. All texts give factual accounts of the revolution with all its contesting powers lingering with mixed references of anxiety and merriment that accentuates their sense of communal solidarity against social corruption and political positioning. Through shifting between the pronouns ‘I’ and ‘we’, these narratives do not solely engage with the personal life of the memorialist; but rather give an account of the collective. Both writers take us to the heart of high-spirited Tahrir Square in 2011 while millions are ranting to oust Hosni Mubarak, the 30 years ruling dictator. By utilizing the instrumentality of collective memory for expressing textual collectivity in their non-fictional writings, these writers are depicting the people power of Egyptians and the historical civil-resistance against governmental unfairness and establishing a certain type of patriotism that elevates and priorities itself from minor conflicts. Their de-individualizing type of life narrative represents the Arabic nation through vital socio-political situations that perpetuate the politics of resistance and collectivity with a constant fear of betraying it and erupts historical moments aiming for an improved future. The texts incorporate an explicit set of reported political series of thought that shape an overall public argument and representational ideas.

Keywords: resistance narrative, life-writing, Tahrir memoir, Middle Eastern literature

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Authors: Kira Toxopeus, Kamran Siddiqui

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Channel flows are common in a wide range of engineering applications. In some types of channel flows, particularly the ones involving chemical or biological processes, the control of the flow temperature is crucial to maintain the optimal conditions for the chemical reaction or to control the growth of biological species. This often becomes an issue when the flow experiences temperature fluctuations due to external conditions. While active heating and cooling could regulate the channel temperature, it may not be feasible logistically or economically and is also regarded as a non-sustainable option. Thermal energy storage utilizing phase change material (PCM) could provide the required thermal regulation sustainably by storing the excess heat from the channel and releasing it back as required, thus regulating the channel temperature within a range in the proximity of the PCM melting temperature. However, in designing such systems, the configuration of the PCM storage within the channel is critical as it could influence the channel flow dynamics, which would, in turn, affect the heat exchange between the channel fluid and the PCM. The present research is focused on the investigation of the flow dynamical behavior in the channel during heat transfer from the channel flow to the PCM thermal energy storage. Offset vertical columns in a narrow channel were used that contained the PCM. Two different column shapes, square and circular, were considered. Water was used as the channel fluid that entered the channel at a temperature higher than that of the PCM melting temperature. Hence, as the water was passing through the channel, the heat was being transferred from the water to the PCM, causing the PCM to store the heat through a phase transition from solid to liquid. Particle image velocimetry (PIV) was used to measure the two-dimensional velocity field of the channel flow as it flows between the PCM columns. Thermocouples were also attached to the PCM columns to measure the PCM temperature at three different heights. Three different water flow rates (0.5, 0.75 and 1.2 liters/min) were considered. At each flow rate, experiments were conducted at three different inlet water temperatures (28ᵒC, 33ᵒC and 38ᵒC). The results show that the flow rate and the inlet temperature influenced the flow behavior inside the channel.

Keywords: channel flow, phase change material, thermal energy storage, thermal regulation

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Authors: Ana M. G. Sperandio, Adriana A. C. Rosa, Jussara C. Guarnieri

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This study consists of a research of the Post Occupancy Assessment (POA) of Medicinal Gardens' project of Urban Social Center’s square, in the city of 'Santa Barbara d'Oeste', located in the interior of Sao Paulo, Brazil. In view of the fact that community gardens, as well as medicinal gardens, are based on innumerable functions. The addition to the pedagogical function rescues people from their origins through (re)contact with the land, as a vehicle for social integration. Bearing in mind the project has the potential to fight hunger among the low-income population, to treat some diseases, also works as a strategy of environmental recovery especially of idle land. Such as very often only accumulate weeds and garbage, and therefore, must be considered in the Municipal Master Plan for the activity to be regulated. Objective: Identify on implantation the medicinal plants' value and principles for the promotion of a healthy city. Methodology: Application of the walkthrough, where it is possible to affirm that this instrument has three routes: one officer applied within the urban social center and two complementary ones, one being about 3 miles and the other being almost 5,5 miles. Results: Through a dialogical course, one can observe the benefits that the community medicinal gardens bring to the local population. In addition, it is consistent with the proposal for the community to be enabled to access collective care with home orientations that rescue the local and regional culture making the physical environment. This project aims at promoting more pleasant and inclusive through the actions of the caregiver, local leadership and the co-participation of local government. Although with the aim of increasing the supply value and improving the living conditions of social groups and interrelationship. Conclusion: This type of urban intervention, which articulates social participation, rescue of medicinal cultures and local knowledge, intersectoriality, social inclusion, among other premises connected with health promotion, and the city presents a potential for reverberation of practices in social networks with the objective of meeting the healthy city strategies.

Keywords: healthy city, healthy urban planning, medicinal gardens, social participation

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Authors: Sertac Arslan, Sezer Kefeli

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In this paper, firstly supercavitating phenomenon and supercavity shape design parameters are explained and then drag force calculation methods of high speed supercavitating torpedoes are investigated with numerical techniques and verified with empirical studies. In order to reach huge speeds such as 200, 300 knots for underwater vehicles, hydrodynamic hull drag force which is proportional to density of water (ρ) and square of speed should be reduced. Conventional heavy weight torpedoes could reach up to ~50 knots by classic underwater hydrodynamic techniques. However, to exceed 50 knots and reach about 200 knots speeds, hydrodynamic viscous forces must be reduced or eliminated completely. This requirement revives supercavitation phenomena that could be implemented to conventional torpedoes. Supercavitation is the use of cavitation effects to create a gas bubble, allowing the torpedo to move at huge speed through the water by being fully developed cavitation bubble. When the torpedo moves in a cavitation envelope due to cavitator in nose section and solid fuel rocket engine in rear section, this kind of torpedoes could be entitled as Supercavitating Torpedoes. There are two types of cavitation; first one is natural cavitation, and second one is ventilated cavitation. In this study, disk cavitator is modeled with natural cavitation and supercavitation phenomenon parameters are studied. Moreover, drag force calculation is performed for disk shape cavitator with numerical techniques and compared via empirical studies. Drag forces are calculated with computational fluid dynamics methods and different empirical methods. Numerical calculation method is developed by comparing with empirical results. In verification study cavitation number (σ), drag coefficient (CD) and drag force (D), cavity wall velocity (U

Keywords: cavity envelope, CFD, high speed underwater vehicles, supercavitation, supercavity flows

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Authors: Shalini Saini, Sharmila Ahuja

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Anaesthesia for caesarean section poses challenges unique to the obstetric patient due to changes in the airway and respiratory system. The choice of anaesthesia for caesarean section depends on various factors however general anaesthesia (GA) is necessary for certain situations. Supraglottic airway devices are an emerging method to secure airway, especially in difficult situations. Of these devices, proseal –LMA (PLMA) is designed to provide better protection of the airway. The use of PLMA has been reported successfully as a rescue device in difficult intubation situations and in patients undergoing elective caesarean section without any complications. The study was prospective and randomised and was designed to compare PLMA in patients undergoing elective lower segment caesarean section (LSCS) with the endotracheal tube (ETT). Patients undergoing LSCS under GA belonging to ASA grade 1 and 2 were included. Patients with the history of fewer than 6 hrs of fasting, known/predicted difficult airway, obesity, gastroesophageal reflux disease, hypertensive disorder were excluded. A standard anaesthesia protocol was followed. All patients received aspiration prophylaxis. The airway was secured with either PLMA or ETT. Parameters noted were- ease of insertion, adequacy of ventilation, hemodynamic changes at insertion and removal of device, incidence of regurgitation and aspiration. Data was analysed by unpaired t- test, Chi-square /Fisher’s test. The findings of our study indicated that PLMA was easy to insert (20.67±6.835 sec) with comparable insertion time to TT (18.33 ± 4.971, p 0.136) and adequate ventilation was achieved with very minimal hemodynamic changes seen with PLMA as compared to ETT at insertion and removal of devices (p 0.01). There was no incidence of regurgitation with the use of PLMA. The incidence of a postoperative sore throat was minimal (6.7%) with PLMA (p<0.05). PLMA appears to be a safe alternative to ETT for selected obstetric patients undergoing elective LSCS. Further study with a larger group of patients is required to establish the safety of PLMA in obstetric patients.

Keywords: caesarean section, general anaesthesia, proseal LMA, endotracheal tube

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Authors: Molla Tadesse Lakew

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This study was intended to identify the factors influencing the use of mobile phones in vegetable marketing in Fogera district. The use of mobile phones in vegetable marketing and factors influencing mobile phone use were specific objectives of the study. Three kebeles from the Fogera district were selected purposively based on their vegetable production potential. A simple random sampling technique (lottery method) was used to select 153 vegetable producer farmers. Interview schedule and key informants interviews were used to collect primary data. For analyzing the data, descriptive statistics like frequency and percentage, two independent t-tests, and chi-square were used. Furthermore, econometric analysis (binary logistic model) was used to assess the factors influencing mobile phone use for vegetable market information. Contingency coefficient and variance inflation factor were used to check multicollinearity problems between the independent variables. Of 153 respondents, 82 (61.72%) were mobile phone users, while 71 (38.28 %) were mobile phone nonusers. Moreover, the main use of mobile phones in vegetable marketing includes communicating at a distance to save time and minimizing transport costs, getting vegetable marketing price information, identifying markets and buyers to sell the vegetable, deciding when to sell the vegetable, negotiating with buyers for better vegetable prices and for searching of the fast market to avoid from losing of product through perishing. The model result indicated that the level of education, size of land, income, access to credit, and age were significant variables affecting the use of mobile phones in vegetable marketing. It could be recommended to encourage adult education or give training for farmers on how to operate mobile phones and create awareness for the elderly rural farmers as they are able to use the mobile phone for their vegetable marketing. Moreover, farmers should be aware that mobile phones are very important for those who own very small land to get maximum returns from their production. Lastly, providing access to credit and improving and diversifying income sources for the farmers to have mobile phones were recommended to improve the livelihood of farmers.

Keywords: mobile phone, farmers, vegetable marketing, Fogera District

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Authors: Alex Fedoseyev

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This study explores Generalized Hydrodynamic Equations (GHE) for the simulation of turbulent flows. The GHE was derived from the Generalized Boltzmann Equation (GBE) by Alexeev (1994). GBE was obtained by first principles from the chain of Bogolubov kinetic equations and considered particles of finite dimensions, Alexeev (1994). The GHE has new terms, temporal and spatial fluctuations compared to the Navier-Stokes equations (NSE). These new terms have a timescale multiplier τ, and the GHE becomes the NSE when τ is zero. The nondimensional τ is a product of the Reynolds number and the squared length scale ratio, τ=Re*(l/L)², where l is the apparent Kolmogorov length scale, and L is a hydrodynamic length scale. The turbulence phenomenon is not well understood and is not described by NSE. An additional one or two equations are required for the turbulence model, which may have to be tuned for specific problems. We show that, in the case of the GHE, no additional turbulence model is needed, and the turbulent velocity profile is obtained from the GHE. The 2D turbulent channel and circular pipe flows were investigated using a numerical solution of the GHE for several cases. The solutions are compared with the experimental data in the circular pipes and 2D channels by Nicuradse (1932, Prandtl Lab), Hussain and Reynolds (1975), Wei and Willmarth (1989), Van Doorne (2007), theory by Wosnik, Castillo and George (2000), and the relevant experiments on Superpipe setup at Princeton, data by Zagarola (1996) and Zagarola and Smits (1998), the Reynolds number is from Re=7200 to Re=960000. The numerical solution data compared well with the experimental data, as well as with the approximate analytical solution for turbulent flow in channel Fedoseyev (2023). The obtained results confirm that the Alexeev generalized hydrodynamic theory (GHE) is in good agreement with the experiments for turbulent flows. The proposed approach is limited to 2D and 3D axisymmetric channel geometries. Further work will extend this approach by including channels with square and rectangular cross-sections.

Keywords: comparison with experimental data. generalized hydrodynamic equations, numerical solution, turbulent boundary layer, turbulent flow in channel

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Authors: Artur Tyliszczak, Ewa Szymanek, Maciej Marek

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Flow through granular materials is important to a vast array of industries, for instance in construction industry where granular layers are used for bulkheads and isolators, in chemical engineering and catalytic reactors where large surfaces of packed granular beds intensify chemical reactions, or in energy production systems, where granulates are promising materials for heat storage and heat transfer media. Despite the common usage of granulates and extensive research performed in this field, phenomena occurring between granular solid elements or between solids and fluid are still not fully understood. In the present work we analyze the heat exchange process between the flowing medium (gas, liquid) and solid material inside the granular layers. We consider them as a composite of isolated solid elements and inter-granular spaces in which a gas or liquid can flow. The structure of the layer is controlled by shapes of particular granular elements (e.g., spheres, cylinders, cubes, Raschig rings), its spatial distribution or effective characteristic dimension (total volume or surface area). We will analyze to what extent alteration of these parameters influences on flow characteristics (turbulent intensity, mixing efficiency, heat transfer) inside the layer and behind it. Analysis of flow inside granular layers is very complicated because the use of classical experimental techniques (LDA, PIV, fibber probes) inside the layers is practically impossible, whereas the use of probes (e.g. thermocouples, Pitot tubes) requires drilling of holes inside the solid material. Hence, measurements of the flow inside granular layers are usually performed using for instance advanced X-ray tomography. In this respect, theoretical or numerical analyses of flow inside granulates seem crucial. Application of discrete element methods in combination with the classical finite volume/finite difference approaches is problematic as a mesh generation process for complex granular material can be very arduous. A good alternative for simulation of flow in complex domains is an immersed boundary-volume penalization (IB-VP) in which the computational meshes have simple Cartesian structure and impact of solid objects on the fluid is mimicked by source terms added to the Navier-Stokes and energy equations. The present paper focuses on application of the IB-VP method combined with large eddy simulation (LES). The flow solver used in this work is a high-order code (SAILOR), which was used previously in various studies, including laminar/turbulent transition in free flows and also for flows in wavy channels, wavy pipes and over various shape obstacles. In these cases a formal order of approximation turned out to be in between 1 and 2, depending on the test case. The current research concentrates on analyses of the flows in dense granular layers with elements distributed in a deterministic regular manner and validation of the results obtained using LES-IB method and body-fitted approach. The comparisons are very promising and show very good agreement. It is found that the size, number of elements and their distribution have huge impact on the obtained results. Ordering of the granular elements (or lack of it) affects both the pressure drop and efficiency of the heat transfer as it significantly changes mixing process.

Keywords: granular layers, heat transfer, immersed boundary method, numerical simulations

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Authors: Jesryl B. Paulite, Eixer Niel V. Enesco

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Lettuce is not well known in the lowland locality in the tropical countries like Philippines. Farmers thought that this crop is not adaptable to the climate that we have in lowland. But some new varieties can tolerate warmer conditions. The massive use of pesticides in lettuce production might chronically affect human health and environment. The move of the Philippine government is toward organic. One of the organic material is vermicompost. It is an organic fertilizer that serves as soil conditioner and enhances soil fertility and promotes vigorous and healthy crop growth and Supplementation of 19-19-19+M.E. will make it better since it contains N-P-K and selected microelements to meet the nutritive requirements of the crop. The experiment was conducted at Purok 3, Brgy. Tiburcia, Kapalong, Davao del Norte from February 6, 2014 to March 4, 2014. The study was conducted to determine the effect of varying frequency application of vermicast as supplemented with 19-19-19+M.E. in lettuce. Specifically, this aimed to 1.) Identify the agronomic performance of lettuce as affected by varying frequency application of vermicast as supplemented with 19-19-19+M.E.; 2.) Assess the economic profitability of lettuce as applied with vermicast as supplemented with 19-19-19+M.E. The study was laid out in Randomized Complete Block Design (RCBD) with four treatments and three replications. The treatments were as follow: T1 – Untreated, T2 - Weekly Application, T3- Bi-weekly Application, and T4- Monthly Application. The data on percent (%) mortality were transformed using square root of transformation before Analysis of Variance (ANOVA). Results revealed not significant in terms of percent mortality in weekly and monthly application of the treatment having a mean of 1.76 % and 3.09 %. However, Significant differences were observed in agronomic performances such as; plant height with a mean of 10.63 cm in weekly application and 6.40 cm for the untreated, leaf width with a mean of 10.80 cm for the weekly application and 6.03 for the untreated, fresh weight with a mean of 25.67 g for the weekly application and 6.83 g for the untreated, and yield with a mean of 1,208.33 kg/ha for the weekly application and 327.08 kg/ha for the untreated, respectively. Results further exposed that profitability of lettuce in terms of Return of Production Cost (RPC) were; bi-weekly with 91.01 %, monthly with 68.20 %, weekly with 25.34 % and untreated (control) with 16.69 %.

Keywords: agronomic performance, economic profitability, vermicast, percent mortality, 19-19-19+ME

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Authors: Abanda Wilfred Chick

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Background: According to World Health Organization (WHO), the role of Information and Communication Technologies (ICT) in health sectors of developing nations has been demonstrated to have had a great improvement of fifty percent reduction in mortality and or twenty-five-fifty percent increase in productivity. The objective of this study was to assess the use of information and communication technologies in enhancing health care delivery for Human Immunodeficiency Virus (HIV) patients in Bamenda Health District. Methods: This was a descriptive-analytical cross-sectional study in which 388 participants were consecutively selected amongst health personnel and HIV patients from public and private health institutions involved in Human Immunodeficiency Virus management. Data on socio-demographic variables, the use of information and communication technologies tools, and associated challenges were collected using structured questionnaires. Descriptive statistics with a ninety-five percent confidence interval were used to summarize findings, while Cramer’s V test, logistic regression, and Chi-square test were used to measure the association between variables, Epi info version7.2, MS Excel, and SPSS version 25.0 were utilized for data entry and statistical analysis respectively. Results: Of the participants, one-quarter were health personnel, and three-quarters were HIV patients. For both groups of participants, there was a significant relationship between the use of ICT and demographic information such as level of education, marital status, and age (p<0.05). For the impediments to using ICT tools, a greater proportion identified the high cost of airtime or internet bundles, followed by an average proportion that indicated inadequate training on ICT tools; for health personnel, the majority said inadequate training on ICT tools/applications and half said unavailability of electricity. Conclusion: Not up to half of the HIV patients effectively make use of ICT tools/applications to receive health care. Of health personnel, three quarters use ICTs, and only one quarter effectively use mobile phones and one-third of computers, respectively, to render care to HIV patients.

Keywords: ICT tools, HIV patients, health personnel, health care delivery

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Authors: Sanchita B. Sarma, M. P. Nath

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Adequate analgesia following caesarean section decreases morbidity, hastens ambulation, improves patient outcome and facilitates care of the newborn. Intrathecal magnesium, an NMDA antagonist, has been shown to prolong analgesia without significant side effects in healthy parturients. The aim of this study was to evaluate the onset and duration of sensory and motor block, hemodynamic effect, postoperative analgesia, and adverse effects of magnesium or fentanyl given intrathecally with hyperbaric 0.5% bupivacaine in patients with mild preeclampsia undergoing caesarean section. Sixty women with mild preeclampsia undergoing elective caesarean section were included in a prospective, double blind, controlled trial. Patients were randomly assigned to receive spinal anesthesia with 2 mL 0.5% hyperbaric bupivacaine with 12.5 µg fentanyl (group F) or 0.1 ml of 50% magnesium sulphate (50 mg) (group M) with 0.15ml preservative free distilled water. Onset, duration and recovery of sensory and motor block, time to maximum sensory block, duration of spinal anaesthesia and postoperative analgesic requirements were studied. Statistical comparison was carried out using the Chi-square or Fisher’s exact tests and Independent Student’s t-test where appropriate. The onset of both sensory and motor block was slower in the magnesium group. The duration of spinal anaesthesia (246 vs. 284) and motor block (186.3 vs. 210) were significantly longer in the magnesium group. Total analgesic top up requirement was less in group M. Hemodynamic parameters were similar in both the groups. Intrathecal magnesium caused minimal side effects. Since Fentanyl and other opioid congeners are not available throughout the country easily, magnesium with its easy availability and less side effect profile can be a cost effective alternative to fentanyl in managing pregnancy induced hypertension (PIH) patients given along with Bupivacaine intrathecally in caesarean section.

Keywords: analgesia, magnesium, pre eclampsia, spinal anaesthesia

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Authors: Marja A. Bernardo, Coreena A. Bueser, Cybele Lara R. Abad, Raul V. Destura

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Pneumocystis jirovecii pneumonia (PCP) is the most common opportunistic infection among people with HIV. Early consideration of PCP should be made even in patients whose HIV status is unknown as delay in treatment may be fatal. The use of absolute lymphocyte count (ALC) has been suggested as an alternative predictor of PCP especially in resource limited settings where PCR testing is costly or delayed. Objective: To determine whether the absolute lymphocyte count (ALC) can be used as a screening tool to predict Pneumocystis pneumonia in patients with unknown HIV status admitted at a private tertiary hospital. Methods: A retrospective cross-sectional study was conducted at a private tertiary medical center. Inpatient medical records of patients aged 18 years old and above from January 2012 to May 2014, in whom a clinical diagnosis of Pneumocystis jirovecii pneumonia was made were reviewed for inclusion. Demographic data, clinical features, hospital course, PCP PCR and HIV results were recorded. Independent t-test and chi-square analysis was used to determine any statistical difference between PCP-positive and PCP-negative groups. Mann-Whitney U-test was used for comparison of hospital stay. Results: There were no statistically significant differences in baseline characteristics between PCP positive and negative groups. While both the percent lymphocyte count (0.14 ± 0.13 vs 0.21 ± 0.16) and ALC (1160 ± 528.67 vs 1493.70 ± 988.61) were lower for the PCP-positive group, only the percent lymphocyte count reached a statistically significant difference (p= 0.067 vs p= 0.042). Conclusion: A quick determination of the ALC may be useful as an additional parameter to help screen for and diagnose pneumocystis pneumonia. In our study, the ALC of patients with PCP appear to be lower than in patients without PCP. A low ALC (e.g. below 1200) may help with the decision regarding empiric treatment. However, it should be used in conjunction with the patient’s clinical presentation, as well as other diagnostic tests. Larger, prospective studies incorporating the ALC with other clinical predictors are necessary to optimally predict those who would benefit from empiric or expedited management for potential PCP.

Keywords: Pneumocystis carinii pneumonia, Absolute Lymphocyte Count, infection, PCP

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Authors: Erinma Chibuzo Nwandu

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Graduates unemployment has risen astronomically in spite of the emphasis on teaching of small scale business and Entrepreneurship in schools. This study sets out to evaluate the effect of teaching small scale business and Entrepreneurship on graduates’ unemployment in Nigeria. This study adopted the survey research design. Thus the nature of data for this study is primary, sourced by the use of a questionnaire administered to a sample of two thousand and sixty-five (2065) respondents drawn from groups of graduates who are employed, unemployed and self-employed in South East Nigeria. Simple percentages, Chi-square and regression analysis were used to derive useful and meaningful information and test the hypotheses respectively. Findings from the study suggest that Nigeria graduates are ill prepared to embark on small-scale business and entrepreneurship after graduation, and that teaching of small scale business and entrepreneurship in Nigeria tertiary institutions is ineffective on graduate unemployment reduction. Findings also suggest that while a lot of graduates agreed that they have taken a class(s) on small scale or entrepreneurship, they received more theoretical teachings than practical, more so while teachings on small scale business or entrepreneurship motivated graduates to think of self-employment, most of them cannot do a good business plan and hence could not benefit from some kind of Government assisted program for small-scale business and bank loan for the sake of small scale business. Thus, so many graduates are not interested in small scale business or entrepreneurship development as a result of lack of startup capital. The study thus recommends that course content and teaching method of entrepreneurship education needs to be reviewed and re-structured to constitute more practical teachings than theoretical teachings. Also, graduates should be exposed to seminar /workshop for self-employment at least once every semester. There should be practical teaching and practice of developing a business plan that will be viable to attract government or private sponsorship as well for it to be viable to attract financing from financing institutions. Government should provide a fund such as venture capital financing arrangement to empower business startups in Nigeria by graduates’.

Keywords: entrepreneurship, small scale business, startup capital, unemployment

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Authors: Abdul Rashid, Varsha Rokade

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Service Quality within retail units is pivotal for satisfying customers and retaining them. This study on customer perception towards Service Quality variables in Retail aims to identify the dimensions and their impact on customers. An analytical study of the different retail service quality variables was done to understand the relationship between them. The study tries exploring the factors that attract the customers towards the organised and unorganised retail stores in the capital city of Madhya Pradesh, India. As organised retailers are seen as offering similar products in the outlets, improving service quality is seen as critical to ensuring competitive advantage over unorganised retailers. Data were collected through a structured questionnaire on a five-point Likert scale from existing walk-in customers of selected organised and unorganised retail stores in Bhopal City of Madhya Pradesh, India. The data was then analysed by factor analysis using (SPSS) Statistical Package for the Social Sciences especially Percentage analysis, ANOVA and Chi-Square. This study tries to find interrelationship between various Retail Service Quality dimensions, which will help the retailers to identify the steps needed to improve the overall quality of service. Thus, the findings of the study prove to be helpful in understanding the service quality variables which should be considered by organised and unorganised retail stores in Capital city of Madhya Pradesh, India.Also, findings of this empirical research reiterate the point of view that dimensions of Service Quality in Retail play an important role in enhancing customer satisfaction – a sector with high growth potential and tremendous opportunities in rapidly growing economies like India’s. With the introduction of FDI in multi-brand retailing, a large number of international retail players are expected to enter the Indian market, this intern will bring more competition in the retail sector. For benchmarking themselves with global standards, the Indian retailers will have to improve their service quality.

Keywords: organized retail, unorganised retail, retail service quality, service quality dimension

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Authors: Gi-Young Park, Dong Rak Kwon, Sung Cheol Cho

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Objective: The synovium is known to be involved in many pathological characteristic processes. Also, synovitis is common in advanced osteoarthritis. We aimed to evaluate the clinical, radiographic, and ultrasound findings in patients with knee osteoarthritis and to compare the clinical and imaging findings between knee osteoarthritis with and without synovial hypertrophy confirmed by ultrasound. Methods: One hundred knees (54 left, 46 right) in 95 patients (64 women, 31 men; mean age, 65.9 years; range, 43-85 years) with knee osteoarthritis were recruited. The Visual Analogue Scale (VAS) was used to assess the intensity of knee pain. The severity of knee osteoarthritis was classified according to Kellgren and Lawrence's (K-L) grade on a radiograph. Ultrasound examination was performed by a physiatrist who had 24 years of experience in musculoskeletal ultrasound. Ultrasound findings, including the thickness of joint effusion in the suprapatellar pouch, synovial hypertrophy, infrapatellar tendinosis, meniscal tear or extrusion, and Baker cyst, were measured and detected. The thickness of knee joint effusion was measured at the maximal anterior-posterior diameter of fluid collection in the suprapatellar pouch. Synovial hypertrophy was identified as the soft tissue of variable echogenicity, which is poorly compressible and nondisplaceable by compression of an ultrasound transducer. The knees were divided into two groups according to the presence of synovial hypertrophy. The differences in clinical and imaging findings between the two groups were evaluated by independent t-test and chi-square test. Results: Synovial hypertrophy was detected in 48 knees of 100 knees on ultrasound. There were no significant differences in demographic parameters and VAS score except in sex between the two groups (P<0.05). Medial meniscal extrusion and tear were significantly more frequent in knees with synovial hypertrophy than those in knees without synovial hypertrophy. K-L grade and joint effusion thickness were greater in patients with synovial hypertrophy than those in patients without synovial hypertrophy (P<0.05). Conclusion: Synovial hypertrophy in knee osteoarthritis was associated with greater suprapatellar joint effusion and higher K-L grade and maybe a characteristic ultrasound feature of late knee osteoarthritis. These results suggest that synovial hypertrophy on ultrasound can be regarded as a predictor of rapid progression in patients with knee osteoarthritis.

Keywords: knee osteoarthritis, synovial hypertrophy, ultrasound, K-L grade

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Authors: Rahul Paul, Peter Mctaggart, Luke Skinner

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Maintaining public safety and network reliability are the core objectives of all electricity distributors globally. For many electricity distributors, managing vegetation clearances from their above ground assets (poles and conductors) is the most important and costly risk mitigation control employed to meet these objectives. Light Detection And Ranging (LiDAR) is widely used by utilities as a cost-effective method to inspect their spatially-distributed assets at scale, often captured using high powered LiDAR scanners attached to fixed wing or rotary aircraft. The resulting 3D point cloud model is used by these utilities to perform engineering grade measurements that guide the prioritisation of vegetation cutting programs. Advances in computer vision and machine-learning approaches are increasingly applied to increase automation and reduce inspection costs and time; however, real-world LiDAR capture variables (e.g., aircraft speed and height) create complexity, noise, and missing data, reducing the effectiveness of these approaches. This paper proposes a method for identifying each conductor from LiDAR data via clustering methods that can precisely reconstruct conductors in complex real-world configurations in the presence of high levels of noise. It proposes 3D catenary models for individual clusters fitted to the captured LiDAR data points using a least square method. An iterative learning process is used to identify potential conductor models between pole pairs. The proposed method identifies the optimum parameters of the catenary function and then fits the LiDAR points to reconstruct the conductors.

Keywords: point cloud, LİDAR data, machine learning, computer vision, catenary curve, vegetation management, utility industry

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Authors: Bianca W. O. Silva, Adriana C. M. Andrade, Gustavo C. M. Lucena, Virna M. S. Lima

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Introduction: Basic life support (BLS) involves the immediate recognition of cardiopulmonary arrest. Each year, 359.400 and 275.000 individuals with cardiac arrest are attended in emergency departments in USA and Europe. Brazilian data shows that 200.000 cardiac arrests occur every year, and half of them out of the hospital. Medical schools around the world teach BLS in the first years of the course, but studies show that there is a decline of the knowledge as the years go by, affecting the chain of survival. The objective was to analyze the knowledge of medical students about BLS and the retention of this learning throughout the course. Methods: This study included 150 students who were at the second and third year of a medical school in Salvador, Bahia, Brazil. The instrument of data collection was a structured questionnaire composed of 20 questions based on the 2015 American Heart Association guideline. The Pearson Chi-square test was used in order to study the association between previous training, sex and semester with the degree of knowledge of the students. The Kruskal-Wallis test was used to evaluate the different yields obtained between the various semesters. The number of correct answers was described by average and quartiles. Results: Regarding the degree of knowledge, 19.6% of the female students reached the optimal classification, a better outcome than the achieved by the male participants. Of those with previous training, 33.33% were classified as good and optimal, none of the students reached the optimal classification and only 2.2% of them were classified as bad (those who did not have 52.6% of correct answers). The analysis of the degree of knowledge related to each semester revealed that the 5th semester had the highest outcome: 30.5%. However, the acquaintance presented by the semesters was generally unsatisfactory, since 50% of the students, or more, demonstrated knowledge levels classified as bad or regular. When confronting the different semesters and the achieved scores, the value of p was 0.831. Conclusion: It is important to focus on the training of medical professionals that are capable of facing emergency situations, improving the systematization of care, and thereby increasing the victims' possibility of survival.

Keywords: basic life support, cardiopulmonary ressucitacion, education, medical students

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Authors: Abdelhalim. N. Mohammed, Mohammed. Y. Esmail

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In the course of recent decades, medical imaging has been dominated by the use of costly film media for review and archival of medical investigation, however due to developments in networks technologies and common acceptance of a standard digital imaging and communication in medicine (DICOM) another approach in light of World Wide Web was produced. Web technologies successfully used in telemedicine applications, the combination of web technologies together with DICOM used to design a web-based and open source DICOM viewer. The Web server allowance to inquiry and recovery of images and the images viewed/manipulated inside a Web browser without need for any preinstalling software. The dynamic site page for medical images visualization and processing created by using JavaScript and HTML5 advancements. The XAMPP ‘apache server’ is used to create a local web server for testing and deployment of the dynamic site. The web-based viewer connected to multiples devices through local area network (LAN) to distribute the images inside healthcare facilities. The system offers a few focal points over ordinary picture archiving and communication systems (PACS): easy to introduce, maintain and independently platforms that allow images to display and manipulated efficiently, the system also user-friendly and easy to integrate with an existing system that have already been making use of web technologies. The wavelet-based image compression technique on which 2-D discrete wavelet transform used to decompose the image then wavelet coefficients are transmitted by entropy encoding after threshold to decrease transmission time, stockpiling cost and capacity. The performance of compression was estimated by using images quality metrics such as mean square error ‘MSE’, peak signal to noise ratio ‘PSNR’ and compression ratio ‘CR’ that achieved (83.86%) when ‘coif3’ wavelet filter is used.

Keywords: DICOM, discrete wavelet transform, PACS, HIS, LAN

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Authors: Stephen Rulisa, Aimee Nyiramahirwe

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Background: Strategies to increase the uptake of contraception services have been adopted in Rwanda, but the unmet need for family planning remains high. Women in the postpartum period are at higher risk for unintended pregnancy due to the silent conversion from lactational amenorrhea to reactivation of ovulatory cycles. The purpose of this study was to explore the role of male partners in the uptake of postpartum contraception. Methods: A prospective cross-sectional study was conducted among women who delivered at the University Teaching Hospital of Kigali for a period of 3 months with random sampling. A questionnaire was used to collect socio-demographic and antenatal data, information on male companionship, and intent to use postpartum contraception at admission. Participants were contacted six weeks later to collect data on contraceptive use. The outcome variables were uptake of postpartum contraception and types of contraceptives taken (long-acting vs. short-acting), controlling for male companionship during the antenatal period. A Chi-square test was used and a p-value ≤0.05 was considered significant. Results: A total of 209 women were recruited with a mean age of 30.8±5.2 years. The majority (60.9%) were multigravida, and 66.5% were multiparous. More than half (55%) had male partner companionship, 18.3% had companionship for four antenatal visits, and 28.2% had education on contraception with their male partner. Factors significantly associated with uptake of postpartum contraception were: age above 30 years, owning or heading a business, multigravidity, multiparity, antenatal care at a health center or district hospital, cesarean delivery, and previous utilization of contraception. Male companionship significantly increased the intent to use contraception, uptake of modern contraception in general, and uptake of long active contraceptives but did not predict the uptake of short-acting contraceptives. Conclusions: Our study demonstrates a positive association between male companionship during antenatal care, labor and delivery with the uptake of postpartum family planning. Our study suggests more sensitization to involve the male partners, improving the education on contraception during antenatal care and further research to assess the sustained uptake of contraception beyond the postpartum period.

Keywords: postpartum, family planning, contraception, male partner, uptake

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Authors: Virginie Hergault, Siham Chebbah, Bertrand Frere

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Following in-house objectives, Central laboratory of Paris police Prefecture conducted a general review on models and Computational Fluid Dynamics (CFD) codes used to simulate pollutant dispersion in the atmosphere. Starting from that review and considering main features of Large Eddy Simulation, Central Laboratory Of Paris Police Prefecture (LCPP) postulates that the Fire Dynamics Simulator (FDS) model, from National Institute of Standards and Technology (NIST), should be well suited for air pollutant dispersion modeling. This paper focuses on the implementation and the evaluation of FDS in the frame of the European COST ES1006 Action. This action aimed at quantifying the performance of modeling approaches. In this paper, the CUTE dataset carried out in the city of Hamburg, and its mock-up has been used. We have performed a comparison of FDS results with wind tunnel measurements from CUTE trials on the one hand, and, on the other, with the models results involved in the COST Action. The most time-consuming part of creating input data for simulations is the transfer of obstacle geometry information to the format required by SDS. Thus, we have developed Python codes to convert automatically building and topographic data to the FDS input file. In order to evaluate the predictions of FDS with observations, statistical performance measures have been used. These metrics include the fractional bias (FB), the normalized mean square error (NMSE) and the fraction of predictions within a factor of two of observations (FAC2). As well as the CFD models tested in the COST Action, FDS results demonstrate a good agreement with measured concentrations. Furthermore, the metrics assessment indicate that FB and NMSE meet the tolerance acceptable.

Keywords: numerical simulations, atmospheric dispersion, cost ES1006 action, CFD model, cute experiments, wind tunnel data, numerical results

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Authors: Charu Sharma

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San Francisco Public Utilities Commission’s Headquarters was listed in the 2013-American Institute of Architects Committee of the Environment (AIA COTE) Top Ten Green Projects. This 13-story, 277,000-square-foot building, housing more than 900 of the agency’s employees was completed in June 2012. It was designed to achieve LEED Platinum Certification and boasts a plethora of green features to significantly reduce the use of energy and water consumption, and provide a healthy office work environment with high interior air quality and natural daylight. Key sustainability features include on-site clean energy generation through renewable photovoltaic and wind sources providing $118 million in energy cost savings over 75 years; 45 percent daylight harvesting; and the consumption of 55 percent less energy and a 32 percent less electricity demand from the main power grid. It uses 60 percent less water usage than an average 13-story office building as most of that water will be recycled for non-potable uses at the site, running through a system of underground tanks and artificial wetlands that cleans and clarifies whatever is flushed down toilets or washed down drains. This is one of the first buildings in the nation with treatment of gray and black water. The building utilizes an innovative structural system with post tensioned cores that will provide the highest asset preservation for the building. In addition, the building uses a “green” concrete mixture that releases less carbon gases. As a public utility commission this building has set a good example for resource conservation-the building is expected to be cheaper to operate and maintain as time goes on and will have saved rate-payers $500 million in energy and water savings. Within the anticipated 100-year lifespan of the building, our ratepayers will save approximately $3.7 billion through the combination of rental savings, energy efficiencies, and asset ownership.

Keywords: energy efficiency, sustainability, resource conservation, asset ownership, rental savings

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Authors: Ranadhir Roy

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Inverse problems arise in medical (molecular) imaging. These problems are characterized by large in three dimensions, and by the diffusion equation which models the physical phenomena within the media. The inverse problems are posed as a nonlinear optimization where the unknown parameters are found by minimizing the difference between the predicted data and the measured data. To obtain a unique and stable solution to an ill-posed inverse problem, a priori information must be used. Mathematical conditions to obtain stable solutions are established in Tikhonov’s regularization method, where the a priori information is introduced via a stabilizing functional, which may be designed to incorporate some relevant information of an inverse problem. Effective determination of the Tikhonov regularization parameter requires knowledge of the true solution, or in the case of optical imaging, the true image. Yet, in, clinically-based imaging, true image is not known. To alleviate these difficulties we have applied the penalty/modified barrier function (PMBF) method instead of Tikhonov regularization technique to make the inverse problems well-posed. Unlike the Tikhonov regularization method, the constrained optimization technique, which is based on simple bounds of the optical parameter properties of the tissue, can easily be implemented in the PMBF method. Imposing the constraints on the optical properties of the tissue explicitly restricts solution sets and can restore uniqueness. Like the Tikhonov regularization method, the PMBF method limits the size of the condition number of the Hessian matrix of the given objective function. The accuracy and the rapid convergence of the PMBF method require a good initial guess of the Lagrange multipliers. To obtain the initial guess of the multipliers, we use a least square unconstrained minimization problem. Three-dimensional images of fluorescence absorption coefficients and lifetimes were reconstructed from contact and noncontact experimentally measured data.

Keywords: constrained minimization, ill-conditioned inverse problems, Tikhonov regularization method, penalty modified barrier function method

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Authors: Elizabeth Perry, Jylana Sheats

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Scholars posit that there is an overlap between the fields of Behavioral Economics (BE) and Behavior Science (BSci)—and that consideration of concepts from both may facilitate a greater understanding of health decision-making processes. For example, the ‘intention-action gap’ is one BE concept to explain sup-optimal decision-making. It is described as having knowledge that does not translate into behavior. Complementary best BSci practices may provide insights into behavioral determinants and relevant behavior change techniques (BCT). Within the context of BSci, this exploratory study aimed to apply a BE concept with demonstrated effectiveness in financial decision-making to a health behavior: influenza (flu) vaccine uptake. Adults aged >18 years were recruited on Amazon’s Mechanical Turk, a digital labor market where anonymous users perform simple tasks at low cost. Eligible participants were randomized into 2 groups, reviewed a scenario, and then completed a survey on the likelihood of receiving a flu shot. The ‘usual care’ group’s scenario included standard CDC guidance that supported the behavior. The ‘intervention’ group’s scenario included messaging about people who did not receive the flu shot. The framing was such that participants could learn from others’ (strangers) mistakes and the subsequent health consequences: ‘Last year, other people who didn’t get the vaccine were about twice as likely to get the flu, and a number of them were hospitalized or even died. Don’t risk it.’ Descriptive statistics and chi-square analyses were performed on the sample. There were 648 participants (usual care, n=326; int., n=322). Among racial/ethnic minorities (n=169; 57% aged < 40), the intervention group was 22% more likely to report that they were ‘extremely’ or ‘moderately’ likely to get the flu vaccine (p = 0.11). While not statistically significant, findings suggest that framing messages from the perspective of learning from the mistakes of unknown others coupled with the BCT ‘knowledge about the health consequences’ may help influence flu vaccine uptake among the study population. With the widely documented disparities in vaccine uptake, exploration of the complementary application of these concepts and strategies may be critical.

Keywords: public health, decision-making, vaccination, behavioral science

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