On the Power Spectral Density of the GSM Signaling Scheme

In this paper, the Power Spectral Density of encoded Gaussian Minimum Shift Keying (GMSK) which is the Signaling Scheme of the Global System for Mobile Communication (GSM) is derived by a combined approach of the autocorrelation method and Markov Process. In the analysis, the Amplitude Modulated Pulse decomposition proposed by P. Laurent is employed to ease computation. Encoding of the message data utilizes Convolutional Code of rate1/2. Results are for both the uncoded and coded waveform comparing variation in power spread over a range of frequency

Evaluation and Performance of Path Profile Characteristics in Communication System

This study presents the evaluation and performance of path profile characteristics in communication system, to determine the path profile characteristics such as margin fade (dB), receiver power (dBm), 2-ray propagation model (dB), free space propagation model (dB), LOSMAX (km) and critical distance (km). Data were obtained from Network ‘A’, using three different links within a geographical location in Edo State. Receiver power is mathematic model, the sensitivity of the receiver, which depends on the bandwidth (data rate) (dBm) of antennas were considered in this analysis. All the path profile characteristics were determined, it was observed, that increase in path length distance of microwave line of sight, will necessitate the increase in transmitter power in decibel. The Path length distance and margin fade of the three basic mobile propagation links were determined. It was observed that path length distance characteristic as such the length of distance, obstacle, reflection, diffraction from ground, water bodies and atmosphere resulted to the pattern of radio margin fade signal obtained in receiver antenna. The margin fade determined are 28.83 dB, 12.95 dB and 21.24 dB for the three different links considered from Network ‘A’ in Auchi, Nigeria

Nonlinear free vibration analysis of levy plates using weak-form variational principle in polynomial displacement functions

This paper evaluates nonlinear free vibrations of Levy plates using Weak-Form variational principle in algebraic polynomial displacement functions. The energy functional of the plate problem was formulated using Weak-Form variational technique on the integral function of the Von Karman thin plate differential equations. The displacement functions were developed based on static deflection configurations of orthogonal beam network. The process of repeated direct integration on compatibility equation was used to determine the algebraic expressions for stress function. The amplitude of deflection which directly influences the geometric nonlinearity of the plate was determined using integration process on energy functional based on static equilibrium equations. The modal combination method was used to develop the stiffness and mass matrices respectively from the expressions of energy functional based on dynamic equilibrium equations. The numerical values of amplitudes of deflection at various aspect ratios were computed. Also, the first four nonlinear natural frequencies at various aspect ratios were numerically computed. The validation of the present study’s results using the results from previous work found in literature shows satisfactory convergence, with an absolute mean error of 0.186 %. Conclusively, the application of Weak-Form variational principle in polynomial displacement functions provides satisfactory approximation to nonlinear dynamic analysis of Levy plates

Influence of the transferred coronavirus infection on diseases of the endocrine system in athletes

Purpose: to study the effect of the transferred viral (on the example of COVID‑19) infection on the endocrine system of athletes.Materials and methods: the data of 1114 athletes (average age 22.23 ± 4.18 years) who underwent in‑depth medical examination in the period 2021–2022 were analyzed. The examination included an analysis of sports and infectious anamnesis, the results of hormonal, biochemical and instrumental studies.Results: coronavirus infection was suffered by the majority of athletes — 724 people (65 %) — in the vast majority of cases (91 %), their disease was asymptomatic or mild. 390 athletes (35 %) had no history of infection. There was a significant increase in the incidence of hypothyroidism, thyrotoxicosis, insulin‑dependent diabetes mellitus, autoimmune thyroiditis among athletes who had a coronavirus infection when compared with athletes who were not ill. The development of endocrine diseases did not depend on the severity of the infection and was most often detected with its mild and asymptomatic course. During the examination, six cases of newly diagnosed type 1 diabetes mellitus and eight cases of thyrotoxicosis were detected among athletes who had a coronavirus infection. The development of these conditions did not depend on the severity of the infection. At the same time, only 1 case of thyrotoxicosis was registered in athletes who were not ill, no new cases of type 1 diabetes mellitus were diagnosed. In the present study, no association was found between the transmitted coronavirus infection and an increase in the number of cases of nodular goiter, hyperprolactinemia and type 2 diabetes mellitus.Conclusion: the results of the study showed that in the long‑term period after COVID‑19, autoimmune endocrine diseases, such as primary hypothyroidism, diffuse‑toxic goiter with thyrotoxicosis, autoimmune thyroiditis, type 1 diabetes mellitus, were significantly more often manifested in athletes, which is probably associated with a cross‑lesion of autoimmunity against a background of viral infection

Early and Late Reoperation Rates With Various MIS Techniques for Adult Spinal Deformity Correction.

Study designA multicenter retrospective review of an adult spinal deformity database.ObjectiveWe aimed to characterize reoperation rates and etiologies of adult spinal deformity surgery with circumferential minimally invasive surgery (cMIS) and hybrid (HYB) techniques.MethodsInclusion criteria were age ≥18 years, and one of the following: coronal Cobb >20°, sagittal vertical axis >5 cm, pelvic tilt >20°, and pelvic incidence-lumbar lordosis >10°. Patients with either cMIS or HYB surgery, ≥3 spinal levels treated with 2-year minimum follow-up were included.ResultsA total of 133 patients met inclusion for this study (65 HYB and 68 cMIS). Junctional failure (13.8%) was the most common reason for reoperation in the HYB group, while fixation failure was the most common reason in the cMIS group (14.7%). There was a higher incidence of proximal junctional failure (PJF) than distal junctional failure (DJF) within HYB (12.3% vs 3.1%), but no significant differences in PJF or DJF rates when compared to cMIS. Early (<30 days) reoperations were less common (cMIS = 1.5%; HYB = 6.1%) than late (>30 days) reoperations (cMIS = 26.5%; HYB = 27.7%), but early reoperations were more common in the HYB group after propensity matching, largely due to infection rates (10.8% vs 0%, P = .04).ConclusionsAdult spinal deformity correction with cMIS and HYB techniques result in overall reoperation rates of 27.9% and 33.8%, respectively, at minimum 2-year follow-up. Junctional failures are more common after HYB approaches, while pseudarthrosis/fixation failures happen more often with cMIS techniques. Early reoperations were less common than later returns to the operating room in both groups, but cMIS demonstrated less risk of infection and early reoperation when compared with the HYB group

Consumer Motivation and Multilevel Marketing on Health Products

Multi Level Marketing (MLM) for healthcare product is one of the dramatic transformations that have emerged in contemporary times with varying behavioral responses. Its increasing acceptance in Nigeria is because people find it an alternative option to addressing diverse health concerns amidst other economic benefits. The study considered multilevel marketing in health with a key focus on the relationship between multilevel health products and continuance intention

Quality of anti-malarial drugs provided by public and private healthcare providers in south-east Nigeria

BACKGROUND: There is little existing knowledge about actual quality of drugs provided by different providers in Nigeria and in many sub-Saharan African countries. Such information is important for improving malaria treatment that will help in the development and implementation of actions designed to improve the quality of treatment. The objective of the study was to determine the quality of drugs used for the treatment of malaria in a broad spectrum of public and private healthcare providers. METHODS: The study was undertaken in six towns (three urban and three rural) in Anambra state, south-east Nigeria. Anti-malarials (225 samples), which included artesunate, dihydroartemisinin, sulphadoxine-pyrimethamine (SP), quinine, and chloroquine, were either purchased or collected from randomly selected providers. The quality of these drugs was assessed by laboratory analysis of the dissolution profile using published pharmacopoeial monograms and measuring the amount of active ingredient using high performance liquid chromatography (HPLC). FINDINGS: It was found that 60 (37%) of the anti-malarials tested did not meet the United States Pharmacopoeia (USP) specifications for the amount of active ingredients, with the suspect drugs either lacking the active ingredients or containing suboptimal quantities of the active ingredients. Quinine (46%) and SP formulations (39%) were among drugs that did not satisfy the tolerance limits published in USP monograms. A total of 78% of the suspect drugs were from private facilities, mostly low-level providers, such as patent medicine dealers (vendors). CONCLUSION: This study found that there was a high prevalence of poor quality drugs. The findings provide areas for public intervention to improve the quality of malaria treatment services. There should be enforced checks and regulation of drug supply management as well as stiffer penalties for people stocking substandard and counterfeit drugs

Physical activity attitudes, intentions and behaviour among 18-25 year olds: a mixed method study

Peer reviewedPublisher PD