South Africa and its COVID-19 prohibition predilection

The year 2020, will forever be marked by the Global pandemic, COVID-19. According to The Department of Health in South Africa until September 15, 2020 3,940,217 tests have been conducted. 651,521 positive cases have been identified, 583,126 recoveries have been reported and there has been a total of 15641 deaths. The South African government have introduced a range of parameters and laws in order to curb the spread of the virus whilst simultaneously endorsing programs to spearhead the preparedness of the healthcare system for the various waves of COVID-19 cases that have been forecast. In conjunction with the new laws and regulations, the South African Government has exercised lockdown and restriction of movement policies. South Africa’s unique, multifaceted and strategic method of combatting the coronavirus has proven to be effective in using existing resources and redirecting both manpower and personnel, thus being of great benefit to all stakeholders and citizens within the country. The prohibition of alcohol is a unique method employed by the government, the full extent to which this policy reform has benefitted the country, its government and its citizens is yet to be fully calculated and projected as South Africa’s coronavirus cases are still increasing on a daily basis. This policy reform will likely find itself becoming a popular trend with crisis management protocols of other countries if the long-term benefits thereof are proven to be true

Enhanced magnetic Purcell effect in room-temperature masers

Recently, the world’s first room-temperature maser was demonstrated. The maser consisted of a sapphire ring housing a crystal of pentacene-doped p-terphenyl, pumped by a pulsed rhodamine-dye laser. Stimulated emission of microwaves was aided by the high quality factor and small magnetic mode volume of the maser cavity yet the peak optical pumping power was 1.4 kW. Here we report dramatic miniaturization and 2 orders of magnitude reduction in optical pumping power for a room-temperature maser by coupling a strontium titanate resonator with the spin-polarized population inversion provided by triplet states in an optically excited pentacene-doped p-terphenyl crystal. We observe maser emission in a thimble-sized resonator using a xenon flash lamp as an optical pump source with peak optical power of 70 W. This is a significant step towards the goal of continuous maser operation

Modulating attentional load affects numerosity estimation: evidence against a pre-attentive subitizing mechanism

Traditionally, the visual enumeration of a small number of items (1 to about 4), referred to as subitizing, has been thought of as a parallel and pre-attentive process and functionally different from the serial attentive enumeration of larger numerosities. We tested this hypothesis by employing a dual task paradigm that systematically manipulated the attentional resources available to an enumeration task. Enumeration accuracy for small numerosities was severely decreased as more attentional resources were taken away from the numerical task, challenging the traditionally held notion of subitizing as a pre-attentive, capacity-independent process. Judgement of larger numerosities was also affected by dual task conditions and attentional load. These results challenge the proposal that small numerosities are enumerated by a mechanism separate from large numerosities and support the idea of a single, attention-demanding enumeration mechanism

Communication characteristics of high-brightness light sources based on luminescence concentration

Communication characteristics of high-brightness solid-state light sources based on luminescence concentration generated using blue emitting InGaN light emitting diode arrays are demonstrated here for the first time. The proposed device is used as a transmitter in visible light communications, and its performance is evaluated

Continuous-wave room-temperature diamond maser

The maser, older sibling of the laser, has been confined to relative obscurity due to its reliance on cryogenic refrigeration and high-vacuum systems. Despite this it has found application in deep-space communications and radio astronomy due to its unparalleled performance as a low-noise amplifier and oscillator. The recent demonstration of a room-temperature solid- state maser exploiting photo-excited triplet states in organic pentacene molecules paves the way for a new class of maser that could find applications in medicine, security and sensing, taking advantage of its sensitivity and low noise. However, to date, only pulsed operation has been observed in this system. Furthermore, organic maser molecules have poor thermal and mechanical properties, and their triplet sub-level decay rates make continuous emission challenging: alternative materials are therefore required. Therefore, inorganic materials containing spin-defects such as diamond and silicon carbide have been proposed. Here we report a continuous-wave (CW) room-temperature maser oscillator using optically pumped charged nitrogen-vacancy (NV) defect centres in diamond. This demonstration unlocks the potential of room-temperature solid-state masers for use in a new generation of microwave devices.Comment: 7 pages, 4 figure

Estimation of the burden of people living with Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) in Kerala state, India.

Background: Worldwide, 36.7 million people were infected with Acquired Immunodeficiency Syndrome (AIDS) by the end of 2015. Over the period 2007 to 2015, there was a declining trend in the prevalence of adult Human Immunodeficiency Virus (HIV) in the state of Kerala, India. The current study aims to find a suitable statistical modelling technique for the distribution of HIV incubation time and predict the cumulative number of AIDS cases. Materials and Methods: The requisite data were obtained from the Kerala State AIDS Control Society (KSACS) for the years 2007 to 2015. To assess the distribution of HIV incubation time, the data of 22 HIV-infected Keralite patients were retrieved from the medical records of a teaching hospital. Data included age, gender, and incubation time. The back-calculation method was utilized to predict the cumulative HIV/AIDS cases. Results: The estimated total cumulative AIDS cases in Kerala for the years 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 and 2015 were found to be 35,777, 48,944, 62,039, 45,669, 45,668, and 43,605, 42,377, 39,362, 37,617, 39,583, 25,414 respectively using back-calculation method with Weibull (2) incubation time distribution. The mean incubation time of the total HIV cases (male and female) was 4.4 years which indicates a rapid progression of the disease in the state of Kerala. Conclusion: The back-calculation method is a powerful tool to estimate the cumulative frequency of AIDS cases; which predicted a declining HIV trend among Keralites. Moreover, the Weibull distribution is the best fitted distribution for HIV incubation time in our population

Cigarette smoking dose-response and suicidal ideation among young people in Nepal: a cross-sectional study

Background: Worldwide, tobacco smoking is a major risk factor for morbidity and early mortality among adult population. The present study aimed to find out the association between current smoking and suicidal ideation among young people in Nepal. Materials and Methods: A cross-sectional questionnaire-based survey was carried out among 452 youths from Pokhara, Nepal. The present study included both genders (age 18-24 years) who were smokers as well as non-smokers. Results: Across the study period, 452 participants were identified after matching for age, and sex (226 in the smoking group and 226 in the non-smoking group). The mean age of participants was 21.6±1.2 years and 58.8% were males. The overall rate of suicidal ideation in our cohort was 8.9%. Smokers were slightly more likely to report suicidal ideation than non-smokers (aOR 1.12). The risk of developing suicidal ideation was 3.56 (95% CI 1.26-10.09) times more in individuals who smoked greater than 3.5 cigarettes per week (p=0.01). Conclusion: The rate of suicidal ideation was slightly higher among smokers and a dose-response relationship was identified with the number of cigarettes smoked per week. Being aware of the link between smoking and suicidal ideation may help health care professionals working with young people to address more effectively the issues of mental well-being and thoughts about suicide

The art of the editorial

Many traditional scientific journals carry an editorial at the start of each issue or perhaps in most issues. The more recently established online journals seemed to have discontinued this tradition, for example there is no editorial in Sociological Research Online or many of the online journals in the BMC stable, such as BMC Pregnancy & Childbirth or BMC Public Health. Over the past two decades we have published close to fifty editorials between us. We would like to highlight some of their specific features to offer advice and encouragement to would-be editorial writers, and, more generally, promote the writing and publishing of editorials. This paper includes an overview of the eight most recent editorials, all focusing on the hot topic of COVID-19, published in this scientific journal

Micro and Nano-plastic particles: What are they and do they effect cardiovascular health?

This editorial in an epidemiology journal highlights how we are damaging the planet and out health with small plastic particles we have dumped in our environment