203 research outputs found
Determination of entrance skin dose from diagnostic X-ray of human chest at Federal Medical Centre Keffi, Nigeria
patient during x-ray examination in Federal Medical Centre, Keffi in Nasarawa state, Nigeria. Entrance skin doses (ESDs) for a common type of x-ray procedures, namely chest AP/PA (anterior/posterior) were measured. A total of 200 data were collected from patients who were exposed to diagnostic X-ray during their routine chest X-ray examinations. The age of the patients ranged from 15 to 68 years old while the weight and height of these patients ranged from 37.5kg to 98.5kg and 130.0cm to 175cm, respectively. The patent’s skin dose were determined using Edmond’s formula, which is based on the X-ray tube and the radiographic exposure parameters of kVp, mAS, SSD and the total filtration of the beams. The calculated mean skin dose ranges from 0.013± 0.01mGy to 0.851±0.023mGy. In general, the ESDs measured for this type of x-ray procedures were found to be lower than or in agreement with the guidance level set by the Nigerian Basic Ionizing Radiation Regulation (NBIRR, 2003) standard and other international bodies and does not pose any significant health risk to the patience or the workers.Keywords: Entrance skin Dose, X-ray, Anterior-Posterior, Exposure, and Radiation
A Comparative Analysis Between the Additive and the Multiplicative Extended Kalman Filter for Satellite Attitude Determination
The general consensus is that the Multiplicative Extended Kalman Filter
(MEKF) is superior to the Additive Extended Kalman Filter (AEKF) based on a
wealth of theoretical evidence. This paper deals with a practical comparison
between the two filters in simulation with the goal of verifying if the
previous theoretical foundations are true. The AEKF and MEKF are two variants
of the Extended Kalman Filter that differ in their approach to linearizing the
system dynamics. The AEKF uses an additive correction term to update the state
estimate, while the MEKF uses a multiplicative correction term. The two also
differ in the state of which they use. The AEKF uses the quaternion as its
state while the MEKF uses the Gibbs vector as its state. The results show that
the MEKF consistently outperforms the AEKF in terms of estimation accuracy with
lower uncertainty. The AEKF is more computationally efficient, but the
difference is so low that it is almost negligible and it has no effect on a
real-time application. Overall, the results suggest that the MEKF is a better
choise for satellite attitude estimation due to its superior estimation
accuracy and lower uncertainty, which agrees with the statements from previous
wor
Occurrence of hypocortisolism in HIV patients: Is the picture changing?
Background: The occurrence of endocrine diseases in people who are infected with HIV is traditionally thought to occur in the setting of AIDS with opportunistic infections and malignancies. However, recent studies find the correlation between hypocortisolism and stage of HIV (CD4 count and WHO clinical stage) inconsistent.Methods: This descriptive cross-sectional study included three hundred and fifty (350) consecutive patients with HIV infection. They were interviewed, and subsequently underwent laboratory evaluation for the detection of hypocortisolism. Blood samples for serum cortisol estimation were taken at baseline and at 30 minutes following the administration of 1μg of tetracosactrin (Synacthen). In addition, the patients had blood samples taken at 0 minutes (baseline) for CD4+ lymphocyte cell counts.Results: At baseline, 108 (30.9%) participants had serum cortisol levels below 100 μg/L with a median value of 55.48 μg/L (11.36-99.96 μg/L), but only 57 (16.3%) study participants had stimulated serum cortisol levels below 180 μg/L with median of 118 μg/L (19.43-179.62). There was no significant difference in the occurrence of clinical features between participants with low and normal serum cortisol, nor WHO clinical stage, CD4 count and ART regimen. The occurrence of hypocortisolism was higher among participants who had been on ART for a longer period of time.Conclusion: There is a high prevalence of hypocortisolism among HIV patients by biochemical testing, especially those who have been on ARVs for a longer duration. Hypocortisolism cannot be predicted based on the participants’ WHO clinical stage of disease, CD4 cell count, or the treatment regimen. Funding: Personal FundsKeywords: HIV, Adrenocortical insufficiency, CD4 cell count, Tetracosactri
Towards a yellow tulp vaccine : preliminary studies exploiting the potential for cross-reactivity with related bufadienolides
Poisoning by Moraea pallida Bak. (yellow tulp) is the most important of all cardiac glycoside induced toxicoses which collectively account for 33% and 10% of deaths in large and small stock due to plant poisoning, respectively, in the Republic of South Africa. This study was conducted to investigate the potential for developing a vaccine against epoxyscillirosidine, the toxin contained by yellow tulp. Epoxyscillirosidine was extracted, isolated, purified and confirmed using 13C NMR spectroscopy. Bufalin and proscillaridine were purchased and together with
epoxyscillirosidine were coupled to BSA and KLH to render them immunogenic. The immunogens (4 mg/ml) were emulsified with an equal volume of Montanide ISA, as an adjuvant. Adult male New Zealand White rabbits (n=15) were randomly assigned to 5 equal groups. Rabbits in groups I, II, III and IV were immunized with proscillaridine-BSA, bufalin-BSA, epoxyscillirosidine-KLH and epoxyscillirosidine-BSA conjugates, respectively. Group V served as control where animals were administered BSA only. The rabbits were immunized on Days 0, 21 and 42 by intradermal injection of 0.1ml of the vaccine at four sites on the dorsum. Blood was collected prior to each vaccination and on Day 67. An ELISA was performed to determine antibody response. Antibodies were raised against proscillaridine, bufalin and epoxyscillirosidine. Furthermore, the antibodies synthesized by
Group I and II rabbits also cross-reacted with epoxyscillirosidine. However, the degree of cross-reactivity was low. This may be enhanced by optimizing the vaccine to induce stronger antibody response. The antibodies will be evaluated to determine the neutralization efficacy against epoxyscillirosidine.Poster presented at the University of Pretoria, Faculty of Veterinary Science Faculty Day, September 07, 2017, Pretoria, South Africa.Includes bibliographical referencesab201
Design and implementation home security system and monitoring by using wireless sensor networks WSN/internet of things IOT
The dramatic advancments on communication and networking technologies have led to the emergence of Internet-of-Things (IoT). IoT technology has opened the door for various applications. In particular, the home automation was one of the common applications that took the advantage of IoT. Several research efforts have addressed the home automation system using IoT covering wide range of functionalities. One of the concerning tasks is providing a secure system that can give alarms for suspicious activities within the house. This paper presents a secure house system based on IoT where several activities are being sensed and detected. Specifically, gas, humidity, body temperature and motion have been considered within the sensing based on two main types of micro-controller including Arduino and Raspberry Pi. Consequentially, an Android prototype has bene developed in order to give an interactive interface for warning the house owner regarding any suscpicious activities. Results of simulation demonstrated the efficancy of the proposed syste
Design and implement WSN/IoT smart parking management system using microcontroller
With the dramatic expansion of new networks such as Wireless Sensor Network (WSN) and Internet-of-Things (IoT), tremendous opportunities have been emerged to incorporate such technologies for valuable tasks. One of these tasks is the smart car parking where there is an imperative demand to manage the parkings in various facilities which may help drivers to save their time. Several research studies have addressed this task using wide range of approaches. However, the energy consumption is still a serious concern. This paper proposes a smart car parking based on cloud-based approach along with variety of sensors. Passive Infrared Sensors (PIRs) have been used to sense the object motion. While Light Dependent Resistor (LDR) sensors have been utilized to sense the light of the parking alarm and display inmformation regarding the occupied and non-occupied parking lots. Finally, multi-micro controller of Arduino have been exploited in order to transmit the information collected to the server. Finally, a prototype Android application has been developed in order to recieve the infromation from the server. Results of simulation showed the efficacy of the proposed method
A comprehensive study of distributed Denial-of-Service attack with the detection techniques
With the dramatic evolution in networks nowadays, an equivalent growth of challenges has been depicted toward implementing and deployment of such networks. One of the serious challenges is the security where wide range of attacks would threat these networks. Denial-of-Service (DoS) is one of the common attacks that targets several types of networks in which a huge amount of information is being flooded into a specific server for the purpose of turning of such server. Many research studies have examined the simulation of networks in order to observe the behavior of DoS. However, the variety of its types hinders the process of configuring the DoS attacks. In particular, the Distributed DoS (DDoS) is considered to be the most challenging threat to various networks. Hence, this paper aims to accommodate a comprehensive simulation in order to figure out and detect DDoS attacks. Using the well-known simulator technique of NS-2, the experiments showed that different types of DDoS have been characterized, examined and detected. This implies the efficacy of the comprehensive simulation proposed by this study
Metabolomic Analysis of Blood and Urine to identify Alcohol-Dependence Biomarkers
The clinical diagnosis of alcohol-dependence (AD) currently relies on AD assessment questionnairesand biomarkers such as Carbohydrate-DeficientTransferrin (CDT), Gamma Glutamyl Transferase (GGT) and Phosphatidylethanol (PEth). However, both methods of diagnosis lackspecificity and sensitivity. Metabolic fingerprinting using nuclear magnetic resonance spectroscopy (NMR)of plasma may give us a novel andaccurate method for the diagnosis of the disease. Our primary objective was to identify the metabolites/biomarkers that could discriminate between subjects diagnosed asAD, social drinkersnon-dependent and healthy control
COVID-19 and diabetes in 2020: a systematic review
Attempts were made to review the literature on diabetic patients who experience complications when they contract
COVID-19, and to determine whether ethnicity and other risk factors play an important role in the development of
symptoms and their severity, as well as responding to medications. A literature search was performed using fve keywords, namely COVID-19, diabetes, ethnicity, medications, and risk factors between January 2019 and December 2020
using electronic databases such as PubMed, Science Direct, Google Scholar, Springer Link, and Scopus. Forty studies
were included. The review indicated that diabetes was a signifcant risk factor for poorer outcomes and increased
mortality associated with COVID-19. There were several risk factors for diabetic patients that increased their likelihood
of poorer outcomes associated with COVID-19. These included black and Asian ethnicity, male sex with high BMI. In
conclusion, patients with diabetes of black or Asian origin with high BMI, male sex, and older age had an increased
risk of poorer outcomes associated with COVID-19. This highlights the importance of considering the history of the
patient in prioritising care and treatment
- …