A grounded CPW transparent UWB antenna for UHF and microwave frequency application

A grounded CPW transparent ultra-wideband (UWB) antenna for Ultra High Frequency (UHF) and microwave frequency application is proposed in this paper. The proposed antenna covers a bandwidth starting from as low as 500MHz to the upper limit of the FCC UWB bandwidth of 10.6 GHz. This enables the antenna to be used for a very wide range of applications ranging from narrow band UHF devices to high data rate UWB transceivers. The antenna is fabricated using AgHT-8 for the CPW and radiator patch on a 1mm thick glass substrate with an Indium Tin Oxide (ITO) ground. The AgHT-8 has a sheet resistance of 8 Ω . m while the ITO, a sheet resistance of 4Ω . m. The overall size of the antenna is 64 × 67mm2. The antenna has a consistent flat 10 dB return loss across the entire bandwidth. The antenna is suitable for integrating onto window glass of homes and buildings as it does not affect the aesthetics of the building. The AgHT-8 layer of the antenna additionally provides sun-shielding from harmful sun-rays and keeps the building cool thus conserving energy required for air-conditioning in hot climates. As such the antenna provides an integrated wireless communication and energy conservation solution for modern day homes and buildings

The prevalence of astigmatism among 7-year-old school children in Gua Musang district: post Covid-19 home confinement

Background: Uncorrected refractive error, including astigmatism remains the major cause of preventable blindness worldwide. The outbreak and spread of the coronavirus disease 2019 (COVID-19) pandemic have greatly impacted education systems worldwide. This study investigated the refractive changes and prevalence of astigmatism in 7-year-old school children in Gua Musang District post COVID-19 home confinement. Methods: In this prospective cross-sectional study, vision screening was conducted on 1832 school children aged 7-year-old, from 13 schools in Gua Musang District, Kelantan. Students that failed the screening were referred to Hospital Gua Musang and undergone cycloplegic refraction. Results: A total of 37 students [33 Malay (89.2%) and 4 Chinese (10.8%)] failed the screening (with visual acuity of less than 6/9). Gender wise, there were 18 males (48.6%) and 19 females (51.4%). The cycloplegic refraction revealed that 9 students (24.3%) had myopia with astigmatism, 14 students (37.85%) had hyperopia with astigmatism, and the other 14 students (37.85%) had astigmatism only. The prevalence of astigmatism post- COVID-19 home confinement was statistically significantly higher (X2=24.96, p<0.001) compared to pre-COVID-19 home confinement (3.5% vs 0.3%). When only the astigmatism component was analysed, all students were found to have with the-rule astigmatism, with 24 students (72.97%) having astigmatism between -1.00DC to -2.75DC, and 10 students (27.03%) having -3.00DC and above. Children with astigmatism showed significantly (X2= 1673.6, p<0.001) visual impairment (uncorrected visual acuity ≥ 6/9) compared to children with no astigmatism (97.1% vs 0.1%). Conclusion: Home confinement during COVID-19 among children appeared to cause a significant astigmatism shift in our study population. Further studies are required to reveal causal relationships with the inter-related factors of near work activity and outdoor activity time

A comprehensive review of barriers to a functional Zakat system in Nigeria: what needs to be done?

Purpose: Muslims in Nigeria, like in many Muslim-majority countries, are striving to have a functional Zakat system in search of solutions to the perennial problem of poverty and its damning consequences. Nevertheless, there are still unsettled concerns arising from the current and widespread implementation of dissimilar (diverse) approaches to the Zakat system in various parts of the country. The purpose of this paper is to review comprehensively what are the hindrances of a vibrant Zakat system and how far the identified impediments may affect the system in the Nigerian context.Design/methodology/approach:The methodology adopted is the review of extant relevant literature in the field of scholarly publications.Findings: The findings of this study revealed that the fragmented implementation of the Zakat system within the context of the Nigerian democratic system of government lead to the weak governance with respect to law, administration and management; lack of a generally accepted fatwa from the Muslims scholars (Ulamas); absence of Zakat accounting standard; and low compliance behavior are the major barriers that require the attention of government and other stakeholders such as the traditional leaders, the accounting regulatory bodies, the Ulamas, as well as the economic and accounting researchers.Practical implications: It was recommended that the stakeholders should make concerted efforts toward ensuring success of the Zakat system for attaining salvation in the hereafter and for social security, as well as economic prosperity. Originality/value: The paper is the first paper that comprehensively reviews previous literature in the Zakat environment on factors that become barriers to implement a comprehensive Zakat system in Nigeria

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was &amp;lt;1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified. © 2023, The Author(s)