The Influence of Gestational Age on the Loss of Maternal Measles Antibodies in Newborn Infants in North-Eastern Nigeria: A Call for a Review of Measles Immunization Schedule

Background: Maternal measles antibodies (MMA) are actively transferred in mother-infant pairs during third trimester of pregnancy. Gestational age (GA) affects the levels of MMA such that longer GA may result in infants starting out with high levels of MMA.Objective: To determine the influence of GA on the loss of MMA in newborn infants in North-Eastern Nigeria.Method: A prospective study was conducted on newborn infants at Maiduguri; sera were collected at birth and at six months of age. Enzyme linked immunosorbent assay (ELISA) was used to measure MMA while GA was determined using the last menstrual period, ultrasound scan reports and the Dubowitz criteria.Results: Seventy eight newborn infants were enrolled. Seventeen (89.5 %) preterm, 43 (95.6 %) term and 14 (100 %) postterm had protective levels of MMA at birth. Two (10.5 %) preterm, nine (20.0%) term and two (14.3 %) postterm had protective MMA at six months of age. Comparison of mean MMA at birth and at six months of age was significant (p = 0.005), however, it was independent of GA of the newborn infants.Conclusion: Significant decline of mean MMA levels was seen in these infants at six months of age, which was independent of their GA. These infants may be prone to measles at an earlier age (less than six months). Therefore, the current recommendation of measles immunization to infants at nine months of age may require reconsideration

IoT Networks: Using Machine Learning Algorithm for Service Denial Detection in Constrained Application Protocol

The paper discusses the potential threat of Denial of Service (DoS) attacks in the Internet of Things (IoT) networks on constrained application protocols (CoAP). As billions of IoT devices are expected to be connected to the internet in the coming years, the security of these devices is vulnerable to attacks, disrupting their functioning. This research aims to tackle this issue by applying mixed methods of qualitative and quantitative for feature selection, extraction, and cluster algorithms to detect DoS attacks in the Constrained Application Protocol (CoAP) using the Machine Learning Algorithm (MLA). The main objective of the research is to enhance the security scheme for CoAP in the IoT environment by analyzing the nature of DoS attacks and identifying a new set of features for detecting them in the IoT network environment. The aim is to demonstrate the effectiveness of the MLA in detecting DoS attacks and compare it with conventional intrusion detection systems for securing the CoAP in the IoT environment. Findings The research identifies the appropriate node to detect DoS attacks in the IoT network environment and demonstrates how to detect the attacks through the MLA. The accuracy detection in both classification and network simulation environments shows that the k-means algorithm scored the highest percentage in the training and testing of the evaluation. The network simulation platform also achieved the highest percentage of 99.93% in overall accuracy. This work reviews conventional intrusion detection systems for securing the CoAP in the IoT environment. The DoS security issues associated with the CoAP are discussed

Effect of Thickness on Structural and Electrical Properties of CuAlS2 Thin Films Grown by Two Stage Vacuum Thermal Evaporation Technique

This work studies the effect of thickness on structural and electrical properties of CuAlS2 thin films grown by two stage vacuum thermal evaporation technique. CuAlS2 thin films of thicknesses 50nm, 100nm and 200nm were deposited on suitably cleaned corning 7059 glass substrate at room temperature (RT). In the first stage Cu-Al precursors were grown at room temperature by thermal evaporation and in the second stage Cu-Al precursors were converted to CuAlS2 thin films by sulfurisation under sulfur atmosphere at the temperature of 673K. The structural properties of the films were examined by X-ray diffraction (XRD) technique while electrical properties of the specimens were studied using four point probe method. The XRD studies revealed that the films are of crystalline in nature having tetragonal structure. The variations of the micro-structural parameters, such as crystallite size (D), dislocation density ( ), and micro-strain ( ), with film thickness were investigated. The results showed that the crystallite sizes increase as the thickness of the film increases. The dislocation density and micro-strain decreases as the thickness increases. The resistivity (  ) of CuAlS2 film is found to decrease with increase in film thickness, which is related to the increase of carrier concentration with film thickness. Thus thicker films exhibit the lowest resistivity and high carrier concentration, implying these are the most conductive films. Low electrical resistivity and high carrier concentration are widely used as the essential components in various optoelectronic devices such as light-emitting diode and photovoltaic cells

PHYTOCHEMICALS AND HYPOGLYCEMIC PROPERTIES OF METHANOL LEAF EXTRACT OF PHYLLANTHUS AMARUS

Plants and plant products are continuously being explored in medicine against diabetics. In the present study, phytochemical screening and hypoglycemic properties of methanol leaf extract of Phyllanthus amarus against alloxan-induced diabetic rats were conducted. A total of fifteen (15) albino rats were randomly selected into 5 groups of 3 rats per group. Groups 1-3 rats were treated with   250 and 500 mg/kg methanol extract of Phyllanthus amarus and 5 mg/kg of glibenclamide respectively, while groups 4 and 5 served as diabetic and normal controls respectively. All treatments were administered orally, once daily for fifteen days. Results revealed the presence of alkaloids, terpenoids, saponins, glycosides, flavonoids, total phenols and tannins. A significant (P<0.05) and a progressive increase in blood glucose level were observed in diabetic untreated rats throughout the experimental periods. At the end of the treatment period rat treated with 250 & 500 mg/kg, P. amarus had final glucose level of 117.00±5.43 mg/dl & 106.00±4.56 mg/kg. Rats treated with 2.5mg/kg glibenclamide had final glucose level of 117.33±5.43 while the untreated rat had final glucose level of 562.50±15.45 mg/dl. The extract of phyllanthus amarus at 250 and 500 mg/kg also cause a significant improvement in body weight gain of the rat. It is concluded that phyllanthus amarus contains some useful phytochemicals with potential hypoglycemic reputations. Thus, it may be considered as a natural source of the drug for therapeutic purposes

Effect of Thickness on Structural and Electrical Properties of CuAlS2 Thin Films Grown by Two Stage Vacuum Thermal Evaporation Technique

This work studies the effect of thickness on structural and electrical properties of CuAlS2 thin films grown by two stage vacuum thermal evaporation technique. CuAlS2 thin films of thicknesses 50nm, 100nm and 200nm were deposited on suitably cleaned corning 7059 glass substrate at room temperature (RT). In the first stage Cu-Al precursors were grown at room temperature by thermal evaporation and in the second stage Cu-Al precursors were converted to CuAlS2 thin films by sulfurisation under sulfur atmosphere at the temperature of 673K. The structural properties of the films were examined by X-ray diffraction (XRD) technique while electrical properties of the specimens were studied using four point probe method. The XRD studies revealed that the films are of crystalline in nature having tetragonal structure. The variations of the micro-structural parameters, such as crystallite size (D), dislocation density ( ), and micro-strain ( ), with film thickness were investigated. The results showed that the crystallite sizes increase as the thickness of the film increases. The dislocation density and micro-strain decreases as the thickness increases. The resistivity (  ) of CuAlS2 film is found to decrease with increase in film thickness, which is related to the increase of carrier concentration with film thickness. Thus thicker films exhibit the lowest resistivity and high carrier concentration, implying these are the most conductive films. Low electrical resistivity and high carrier concentration are widely used as the essential components in various optoelectronic devices such as light-emitting diode and photovoltaic cells

Effect of Thickness on Structural and Electrical Properties of CuAlS2 Thin Films Grown by Two Stage Vacuum Thermal Evaporation Technique

This work studies the effect of thickness on structural and electrical properties of CuAlS2 thin films grown by two stage vacuum thermal evaporation technique. CuAlS2 thin films of thicknesses 50nm, 100nm and 200nm were deposited on suitably cleaned corning 7059 glass substrate at room temperature (RT). In the first stage Cu-Al precursors were grown at room temperature by thermal evaporation and in the second stage Cu-Al precursors were converted to CuAlS2 thin films by sulfurisation under sulfur atmosphere at the temperature of 673K. The structural properties of the films were examined by X-ray diffraction (XRD) technique while electrical properties of the specimens were studied using four point probe method. The XRD studies revealed that the films are of crystalline in nature having tetragonal structure. The variations of the micro-structural parameters, such as crystallite size (D), dislocation density ( ), and micro-strain ( ), with film thickness were investigated. The results showed that the crystallite sizes increase as the thickness of the film increases. The dislocation density and micro-strain decreases as the thickness increases. The resistivity (  ) of CuAlS2 film is found to decrease with increase in film thickness, which is related to the increase of carrier concentration with film thickness. Thus thicker films exhibit the lowest resistivity and high carrier concentration, implying these are the most conductive films. Low electrical resistivity and high carrier concentration are widely used as the essential components in various optoelectronic devices such as light-emitting diode and photovoltaic cells

Ultrasonic Fluid Level Measuring Device

Accurate measurement of fluid level is very vital both in industrial and consumer market. Ultrasonic technology is one of the solutions used by the industry. However, an optimized balance between cost and features are a must for almost all target applications. The ultrasonic level measurement is used mainly when a non-contact measurement is required. Precise measurement of low-range distance (level) is the main objective for this project. This device can measure level in the range of 0.02m to 4m with an accuracy of 1cm. This measuring system is based on ultrasonic sound utilizing an Atmega328P low-power microcontroller. The system transmits a burst of ultrasonic sound waves towards the subject and then receives the corresponding echo. An HC-SR04 ultrasonic Module is used to both generate and detect the ultrasound required for level computation. The time taken for the ultrasonic burst to travel the distance from the system to the subject and back to the system is accurately measured. This level is displayed on an alphanumeric LCD with an accuracy of ± 2.5cm. The minimum depth that this system can measure is 2cm and is limited by the transmitter's transducer settling-time. The maximum height that can be measured is 4 meters. The amplitude of the echo depends on the reflecting material, shape, and size. Sound-absorbing targets such as carpets and reflecting surfaces less than two square feet in area reflect poorly. The maximum measurable range is lower for such subjects. If the amplitude of the echo received by the system is so low that it is not detectable by the ultrasonic module, the system goes out of range. This is indicated by displaying the error message OOR (Out-of-Range) on the LCD

Factors underlying Ebola virus infection among health workers, Kenema, Sierra Leone, 2014-2015

Background. Ebola virus disease (EVD) in health workers (HWs) has been a major challenge during the 2014-2015 outbreak. We examined factors associated with Ebola virus exposure and mortality in HWs in Kenema District, Sierra Leone. Methods. We analyzed data from the Sierra Leone National Viral Hemorrhagic Fever Database, contact tracing records, Kenema Government Hospital (KGH) staff and Ebola Treatment Unit (ETU) rosters, and burial logs.Results. From May 2014 through January 2015, 600 cases of EVD originated in Kenema District, including 92 (15%) HWs, 66 (72%) of whom worked at KGH. Among KGH medical staff and international volunteers, 18 of 62 (29%) who worked in the ETU developed EVD, compared with 48 of 83 (58%) who worked elsewhere in the hospital. Thirteen percent of HWs with EVD reported contact with EVD patients, while 27% reported contact with other infected HWs. The number of HW EVD cases at KGH declined roughly 1 month after implementation of a new triage system at KGH and the opening of a second ETU within the district. The case fatality ratio for HWs and non-HWs with EVD was 69% and 74%, respectively.Conclusions. The cluster of HW EVD cases in Kenema District is one of the largest ever reported. Most HWs with EVD had potential virus exposure both inside and outside of hospitals. Prevention measures for HWs must address a spectrum of infection risks in both formal and informal care settings as well as in the community.Publisher PDFPeer reviewe

Erratum to 'Exploring the cost-effectiveness of high versus low perioperative fraction of inspired oxygen in the prevention of surgical site infections among abdominal surgery patients in three low- and middle-income countries' [BJA Open 7 (2023) 100207]

[This corrects the article DOI: 10.1016/j.bjao.2023.100207.].</p

Asymptomatic infection and unrecognised Ebola virus disease in Ebola-affected households in Sierra Leone: a cross-sectional study using a new non-invasive assay for antibodies to Ebola virus.

BACKGROUND: The frequency of asymptomatic infection with Ebola virus is unclear: previous estimates vary and there is no standard test. Asymptomatic infection with Ebola virus could contribute to population immunity, reducing spread. If people with asymptomatic infection are infectious it could explain re-emergences of Ebola virus disease (EVD) without known contact. METHODS: We validated a new oral fluid anti-glycoprotein IgG capture assay among survivors from Kerry Town Ebola Treatment Centre and controls from communities unaffected by EVD in Sierra Leone. We then assessed the seroprevalence of antibodies to Ebola virus in a cross-sectional study of household contacts of the survivors. All household members were interviewed. Two reactive tests were required for a positive result, with a third test to resolve any discrepancies. FINDINGS: The assay had a specificity of 100% (95% CI 98·9-100; 339 of 339 controls tested negative) and sensitivity of 95·9% (89·8-98·9; 93 of 97 PCR-confirmed survivors tested positive). Of household contacts not diagnosed with EVD, 47·6% (229 of 481) had high level exposure (direct contact with a corpse, body fluids, or a case with diarrhoea, vomiting, or bleeding). Among the contacts, 12·0% (95% CI 6·1-20·4; 11 of 92) with symptoms at the time other household members had EVD, and 2·6% (1·2-4·7; 10 of 388) with no symptoms tested positive. Among asymptomatic contacts, seropositivity was weakly correlated with exposure level. INTERPRETATION: This new highly specific and sensitive assay showed asymptomatic infection with Ebola virus was uncommon despite high exposure. The low prevalence suggests asymptomatic infection contributes little to herd immunity in Ebola, and even if infectious, would account for few transmissions. FUNDING: Wellcome Trust ERAES Programme, Save the Children