Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method

In this study, natural convection flow in a porous cavity with sinusoidal temperature distribution has been analyzed by a new double multi relaxation time (MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9 lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9 have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement with the previous works, thus confirming the reliability the new numerical method proposed in this paper. It is indicated that the heat transfer rate increases at increasing Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and phase deviation. However, the most sensitive parameter is the Rayleigh number. The maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on the heat transfer rate increases at increasing Rayleigh number, yielding a maximum enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and Ra=$10^5$, respectively.     

How people of African Caribbean or Irish ethnicity cope with long-term health conditions in UK community settings: A systematic review of qualitative,quantitative and mixed method studies

Living with a chronic or mental health condition can be challenging and requires considerable adjustment. As ways of coping are culturally influenced, it is important to understand how minority ethnic populations cope, to inform appropriate services. This review aimed to explore the coping strategies used by UK residents from an African Caribbean or Irish background between 1960 and 2020. A systematic literature search on strategies used to cope with chronic health conditions in both populations living in the United Kingdom identified 26 relevant studies. Data were extracted, quality of papers was appraised and critical interpretive synthesis was applied. Two major foci of the studies were coping strategies and barriers to coping. The main coping strategies were denial/scepticism, self-management, spirituality and religion. Within each population, there was variation in ways of coping. The review highlights the complex role of religion in influencing coping strategies. It demonstrates how personal and minority ethnic populations’ experiences of service use are connected with stigma, fear and mistrust, which also act as barriers to seeking help and to coping. Coping with a chronic or mental health condition in the Irish and African Caribbean populations is under-researched. Stigma, fear and mistrust in services act as key barriers to help-seeking and religion is a prominent coping strategy. However, few detailed examples were given on how it was used to assist individuals when managing a chronic or mental health condition. Also due to a lack of research, firm conclusions cannot be drawn for the Irish population.     

Antihypertensive effect of once daily sustained release isradipine: a placebo controlled cross-over study

Summary To evaluate the magnitude and duration of the antihypertensive effect of sustained release (SRO) isradipine, 37 uncomplicated essential hypertensive patients (diastolic blood pressure 100–115 mm Hg after a one month run-in on placebo) were randomised to receive, according to a double-blind cross-over design, isradipine SRO 5 mg once daily and the corresponding placebo for 1 month. At the end of each treatment period, sitting blood pressure and heart rate were measured immediately before and every hour for 6 h after the last dose. Thirty-four patients [16 m, age 54 (7) y] completed the study.As compared to randomised placebo, isradipine SRO significantly reduced the systolic (SBP) and diastolic (DBP) blood pressure. Absolute DBP decrements versus placebo peaked 6 h after dosing (-8.8 mm Hg) and were not significantly lower (-8.2 mm Hg) at the end of the dose interval. At the same times, the absolute decrements in SBP were -9.8 mm Hg and -9.7 mm Hg, respectively.DBP was normalised in 19 patients (56%) at peak and in 17 (50%) at trough time. The trough to peak efficacy ratio in patients with peak DBP 90 mm Hg was 70%. Heart rate was slightly increased by isradipine SRO. Adverse effects monitored with a check-list occurred in 8/36 patients (22%) on isradipine SRO and in 4/35 (11%) on randomized placebo.The data suggest that isradipine SRO is an effective antihypertensive drug, with a trough to peak efficacy ratio supporting once daily administration in most mild to moderate essential hypertensives.     

Genomic annotation and molecular evolution of monkeypox virus outbreak in 2022

Monkeypox virus (MPXV) has generally circulated in West and Central Africa since its emergence. Recently, sporadic MPXV infections in several nonendemic countries have attracted widespread attention. Here, we conducted a systematic analysis of the recent outbreak of MPXV-2022, including its genomic annotation and molecular evolution. The phylogenetic analysis indicated that the MPXV-2022 strains belong to the same lineage of the MPXV strain isolated in 2018. However, compared with the MPXV strain in 2018, in total 46 new consensus mutations were observed in the MPXV-2022 strains, including 24 nonsynonymous mutations. By assigning mutations to 187 proteins encoded by the MPXV genome, we found that 10 proteins in the MPXV are more prone to mutation, including D2L-like, OPG023, OPG047, OPG071, OPG105, OPG109, A27L-like, OPG153, OPG188, and OPG210 proteins. In the MPXV-2022 strains, four and three nucleotide substitutions are observed in OPG105 and OPG210, respectively. Overall, our studies illustrated the genome evolution of the ongoing MPXV outbreak and pointed out novel mutations as a reference for further studies.     

Nicotine-induced hypothermia through an indirect dopaminergic mechanism

The effect of nicotine on core body temperature was studied in mice. Intraperitoneal (i.p.) injection of nicotine (0.5, 1 and 2 mg/kg) induced a dose-dependent hypothermia. The response was inhibited by reserpine (5 mg/kg), the centrally active nicotinic receptor antagonist mecamylamine (0.1-1 mg/kg) and the D-2 dopamine receptor antagonist sulpiride (25-100 mg/kg). The β-adrenoceptor antagonist propranolol (5 and 10 mg/kg) and the serotonergic blocker methysergide (5 and 10 mg/kg) did not inhibit but increased the nicotine response. The α-adrenoceptor antagonist phenoxybenzamine, the antimuscarinic agent atropine, the D-1 dopamine receptor antagonist SCH 23390, the peripheral dopamine antagonist domperidone and the peripheral nicotinic antagonist hexamethonium did not alter the nicotine-induced hypothermia. It is concluded that nicotine may cause a fall in core body temperature through a central dopaminergic mechanism.     

Efficacy of routine preoperative computed tomography scans in colon cancer

A retrospective review of 180 patients who underwent surgery for primary colon carcinoma from August 1989 to August 1994 was performed to evaluate the necessity of preoperative CT scans in patients with known colon cancer. Sixty-seven patients had preoperative CT scans. Data were collected to evaluate the ability of the scan to detect hepatic metastases, lymph node involvement, and incidental findings that would possibly alter the planned surgical approach. In this study, CT had a sensitivity and specificity of 75 per cent and 88 per cent, respectively, in detecting hepatic metastases. Only 19 per cent of patients with lymph node involvement were correctly staged with CT scans as having lymphadenopathy. Only 3 of 67 patients had incidental findings on CT scans that ultimately changed the surgical approach. It is apparent that because CT scans detect only 75 per cent of hepatic and 19 per cent of hepatic and lymph node involvement and does not seem to alter the planned approach, it is not justified for routine preoperative evaluation of all patients. We, therefore, recommend a more selective approach to patients suspected of having advanced disease if the surgeon suspects that the information may alter the surgical approach.     

Prevention of mother-to-child HIV transmission in resource-poor countries: translating research into policy and practice

Kevin M. De Cock, MD; Mary Glenn Fowler, MD, MPH; Eric Mercier, MD, MPH; Isabelle de Vincenzi, MD, PhD; Joseph Saba, MD; Elizabeth Hoff, MSc; David J. Alnwick, MSc; Martha Rogers, MD; Nathan Shaffer, MD

JAMA. 2000;283:1175-1182.

Each year, an estimated 590,000 infants acquire human immunodeficiency virus type 1 (HIV) infection from their mothers, mostly in developing countries that are unable to implement interventions now standard in the industrialized world. In resource-poor settings, the HIV pandemic has eroded hard-won gains in infant and child survival. Recent clinical trial results from international settings suggest that short-course antiretroviral regimens could significantly reduce perinatal HIV transmission worldwide if research findings could be translated into practice. This article reviews current knowledge of mother-to-child HIV transmission in developing countries, summarizes key findings from the trials, outlines future research requirements, and describes public health challenges of implementing perinatal HIV prevention interventions in resource-poor settings. Public health efforts must also emphasize primary prevention strategies to reduce incident HIV infections among adolescents and women of childbearing age. Successful implementation of available perinatal HIV interventions could substantially improve global child survival.