815 research outputs found
Why do people prefer traditional bonesetters in Sudan?
Background: In Sudan as in other developing nations, traditional bonesetters play a significant role in primary fracture care. There is widespread belief in our society that TBS are better at fracture treatment than orthodox practitioners. Significant numbers of patients with fractures present first to the traditional bonesetters before coming to the hospital and therefore this mode of care delivery cannot be overlooked in Sudan. Objectives: A prospective study designed to determine the reasons of why a considerable number of people prefer to go to the traditional bonesetters in Sudan.Patients and methods: This prospective two stages study was carried out in two different stages, 1st stage in 2006 targeted general population, and the 2nd stage in the period from May 2009 to September 2009 targeted traditional bonesetters and their patients. In the 1st stage of the study we distributed a predesigned questionnaire to general population, while in the 2nd stage of the study we visited different traditional bonesetter in order to interview them and their visitors and completing the early prepared Performa. We excluded the too elderly patients and children who have nodecisions to choose TBS.Results: In the 1st stage of study the participants were 199 of them, 192 participants responded well to the questionnaire. The reasons why they went to traditional bonesetters were; in 71 participants (37%) was their beliefs, in 27 (14.06%) was due to the low cost, and in 27 (14.06%) was due to fear of plaster. In the 2nd stage of the study 276 participants fulfilled the criteria of the research. The reason why they went to traditional bonesetters; in 63 candidates (22.8%) was their beliefs (P value < 0.003), in 53 (19.2%) was low cost (P value < 0.05), and in 46 (16.7%) was due to fear of cast or amputation. Study included sixteen traditional bonesetters, of them 14 were males and 2 were females. One of them has a bachelor graduation from faculty of sciences. 11 (68.8%) traditional bonesetters accepted the idea of regular training under medical supervision.Conclusion: Despite an adequate number of physicians practising in the region, traditional bonesetters continue to be consulted. Study showed that a belief is the most leading cause of consulting traditional bonesetters, other causes including fear of plaster or amputation and less cost. We recommend that the efficacy of their treatments have to be further assessed.Keywords: Traditional bonesetter (TBS); Beliefs, medical services
Nonlinear centrifugal instabilities in curved free shear layers
Curved free shear layers exist in many engineering problems involving complex flow geometries, such as the backward facing step flow, flows with wall injection, the flow inside side-dump combustors, or flows generated by vertical axis wind turbines, among others. Most of the studies involving centrifugal instabilities have been focused on wall flows where Taylor instabilities between two rotating concentric cylinders or Görtler vortices in boundary layers resulting from the imbalance between centrifugal effects and radial pressure gradients, are generated. Curved free shear layers, however, did not receive sufficient attention. An examination of the stability characteristics and the flow structures associated with curved free shear flows should provide a better understanding of these complex flow problems. In this work, we study the development of Görtler vortices inside a curved shear layer in both the incompressible and compressible regimes using a numerical solution to a parabolized form of the Navier-Stokes equations, in the assumption that the streamwise wavenumber associated with the vortex flow is much smaller than the crossstream wavenumbers. Various results consisting of contour plots of centrifugal instabilites in crossflow planes, and energy and streak amplitude distributions along the streamwise direction are reported and discussed. In addition, we conduct a biglobal stability analysis to study the growth rates and the eigenmodes associated with these flows
Profitability analysis of catfish farming in Suleja local government area of Niger state, Nigeria
The problem of profitability and scale of production of catfish has not been properly addressed. This study was conducted in Suleja Local Government Area of Niger State to assess the profitability of catfish production. Forty (40) catfish farmers were selected from the study area using simple random sampling techniques. Structured questionnaire was used to collect data from the respondents. The analytical tools used include, descriptive statistics, net farm income analysis and profitability ratios and multiple regression functions. The result of the analysis showed that the average total cost per kilogram of fish was N321.23k and the average total revenue per kg of fish was N501.31. This gives a net farm income of N180.08k per kilogram of fish farmed. The study also showed that the sum total of elasticity of variables was less than one (0.994), this indicates that catfish farming in the study area is in stage II, which is the rational stage of production. Double-log functional model was chosen as lead equation. The value of R2 was 0.998. The number of ponds (X1) and number of fingerlings (X3) were significant at 1%, while labour(X5) was significant at 5% levels of significance. The F- ratio of 2964.370 was significant at P (< 0.01). This implies that all the explanatory variables taken together have significance on the dependent variable (Y), the output. Due to expensive nature of flow-through and re-circulatory ponds, earthen ponds were mostly preferred by majority (92.5%) of the fish farmers in the study area. The major problems faced by catfish farmers include; water, high cost of feed and capital.Key Words: cat fish, net farm income, profitability rati
The simultaneous effects of the wetting layer, intense laser and the conduction band non-parabolicity on the donor binding energy in a InAs/GaAs conical quantum dot using the numerical FEM
Using the finite element method, we have performed a systematic study on the ground-state binding energy ( of a donor impurity confined in a conical quantum dot (CQD) with wetting layer (WL) and a realistic finite confining potential. The simultaneous effect of the applied electric and magnetic fields as well as the influence of an intense laser field have been performed on the Eb within the effective mass approximation. The band non-parabolicity effect is also considered using the energy dependent effective mass approximation. It has been shown that the Eb is highly dependent on the internal and external CQD structure parameters such as radial thickness, height and WL thickness, external electric, magnetic fields and intense laser field. The results we have obtained show that a quite significant contribution of the WL effects on the ground state energy and the Eb has found at small values of the cone radius. In the low confinement regime, the effect of the conduction band non-parabolicity becomes gradually smaller as the value of the cone radius increases and the influence of high-frequency laser increases with the non-parabolicity effect in the regime of small QD radius. Our results are in good agreement with those obtained in the literature
High rejection self-oscillating up-conversion mixer for fifth-generation communications
This paper presents the design of a pseudomorphic high electron mobility transistor (pHEMT) self-oscillating mixer (SOM) for millimeter wave wireless communication systems. The 180° out-of-phase technique is chosen to both improve the desired lower sideband (LSB) signal and to achieve a satisfactory rejection of the unwanted signals (LO, USB and IF). This SOM is designed on the PH15 process of UMS foundry which is based on 0.15 µm GaAs pHEMT. The signal is up-converted from 2 GHz-IF frequency to 26 GHz-LSB frequency, using an autogenerated 28 GHz-LO signal. Simulations were performed using the advanced design system (ADS) workflow. They show 6.4 dB conversion gain and a signal rejection rate of 29.7 dB for the unwanted USB signal. the chip size is 3.6 mm2
28 GHz balanced pHEMT VCO with low phase noise and high output power performance for 5G mm-Wave systems
This paper presents the study and design of a balanced voltage controlled oscillator VCO for 5G wireless communication systems. This circuit is designed in monolithic microwave integrated circuit (MMIC) technology using PH15 process from UMS foundry. The VCO ensures an adequate tuning range by a single-ended pHEMT varactors configuration. The simulation results show that this circuit delivers a sinusoidal signal of output power around 9 dBm with a second harmonic rejection between 25.87 and 33.83 dB, the oscillation frequency varies between 26.46 and 28.90 GHz, the phase noise is -113.155 and -133.167 dBc/Hz respectively at 1 MHz and 10 MHz offset and the Figure of Merit is -181.06 dBc/Hz. The power consumed by the VCO is 122 mW. The oscillator layout with bias and RF output pads occupies an area of 0.515 mm2
A 5G mm-wave compact voltage-controlled oscillator in 0.25 µm pHEMT technology
A 5G mm-wave monolithic microwave integrated circuit (MMIC) voltage-controlled oscillator (VCO) is presented in this paper. It is designed on GaAs substrate and with 0.25 µm-pHEMT technology from UMS foundry and it is based on pHEMT varactors in order to achieve a very small chip size. A 0dBm-output power over the entire tuning range from 27.67 GHz to 28.91 GHz, a phase noise of -96.274 dBc/Hz and -116.24 dBc/Hz at 1 and 10 MHz offset frequency from the carrier respectively are obtained on simulation. A power consumption of 111 mW is obtained for a chip size of 0.268 mm2. According to our knowledge, this circuit occupies the smallest surface area compared to pHEMTs oscillators published in the literature
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The adherence of doctors to brain CT referral criteria: a service evaluation survey from Basrah teaching hospital
Background: CT scans are increasingly utilised in outpatient and emergency departments due to their ability to facilitate swift diagnosis and treatment planning. However, inappropriate use of CT scans, particularly CT scans of the brain, can have negative consequences.
Objectives: This study aims to evaluate the adherence of Basrah Teaching Hospital doctors to the international referral criteria for brain CT scans.
Methods: A retrospective review of medical records was conducted to investigate the utilisation of brain CT scans in the radiology departments of Basra Teaching Hospital for two months and involved 108 referrals. The medical records were thoroughly reviewed to extract relevant information related to the indications of referral, referring doctor, referring place, brain CT results, and assessing the request form completions. The standard referral criteria were extracted from the United Kingdom and European brain CT referral guidelines.
Results: Most of the referrals (75.9%) met the referral criteria, and most of the doctors, regardless of their levels, met the referral criteria; however, the highest rate was among the junior doctors (88.9%), followed by specialists and senior resident doctors. Moreover, most of the units adhered to the referral criteria, but the highest adherence rate was among those referrals from inpatient wards (91.7%). Furthermore, the majority of the doctors and most of the referring wards completed their request forms; however, the highest completion was in specialty and consultant doctors’ groups (77.8%). The results also showed that about half of positive brain CT results are due to neurological causes (46%), followed by head trauma referral (34.6%).
Conclusions: The majority of the doctors at Basrah Teaching Hospital met the international standards for brain CT referrals, and most of the referral wards followed these guidelines
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