Molten salt reactors offer a wide range of potential benefits but pose some unique challenges, particularly for designs that use an unclad liquid salt fuel. This type of fuel will result in the ...transport of fission gases into the headspace of the reactor where in some designs a cover gas can be circulated to remove certain fission products and maintain an inert atmosphere. The cover gas leaving the reactor core is expected to contain both noble and non-noble gases, aerosols, volatile species, tritium, radionuclides, and their daughters. To remove these radioactive gases, it is necessary to develop a robust off-gas system for molten salt–fueled reactors. Various treatment systems must be staged in series to remove the off-gas constituents from the stream before recirculating the gas back to the headspace of the reactor. Treatment options vary greatly depending on what they are designed to remove from the gas stream. This paper reviews the anticipated composition of a typical molten salt reactor off-gas stream and subsequently the available resources that could be employed to remove these species from the gas stream. An example off-gas system is then detailed, along with important design considerations, exemplifying the necessity for high-fidelity modeling. Lastly, the need for further thermophysical property research and the employment of advanced sensor technology for treatment component testing are discussed.
No datasets are available on the basis of confirmed familial breast cancer patients and their respective mutation status for the South African Indian population. This dataset contains information ...collected in South Africa specifically for the South African Indian population (n = 223). The data involved a combined collection of laboratory confirmed genetic testing results, accompanied by immunohistochemical and anatomical pathology results. Various patient self-identified variables were also in measured. All the immunohistochemistry and anatomical pathology results were confirmed by a trained medical pathologist. Furthermore, mutation status and the detection of either benign polymorphisms or variants with an unknown clinical significance at the time of data collection were also reported. This dataset contains variables in a tabular format which includes the accompanying variables for each patient. All the patient-specific data were deidentified which allows for further exploration of the data with respect to the demography, immunohistochemistry and genetic material. This dataset has the potential to serve as the backbone for translational research and inquiries into this unique South African population.
The purpose of this study was to describe our institutional experience in using inhaled prostacyclin as a selective pulmonary vasodilator in patients with pulmonary hypertension, refractory ...hypoxemia, and right heart dysfunction after cardiothoracic surgery.
Between February 2001 and March 2003, cardiothoracic surgical patients with pulmonary hypertension (mean pulmonary artery pressure >30 mm Hg or systolic pulmonary artery pressure >40 mm Hg), hypoxemia (PaO(2)/fraction of inspired oxygen <150 mm Hg), or right heart dysfunction (central venous pressure >16 mm Hg and cardiac index <2.2 L.min(-1).m(-2)) were prospectively administered inhaled prostacyclin at an initial concentration of 20,000 ng/mL and then weaned per protocol. Hemodynamic variables were measured before the initiation of inhaled prostacyclin, 30 to 60 minutes after initiation, and again 4 to 6 hours later.
One hundred twenty-six patients were enrolled during the study period. At both time points, inhaled prostacyclin significantly decreased the mean pulmonary artery pressure without altering the mean arterial pressure. The average length of time on inhaled prostacyclin was 45.6 hours. There were no adverse events attributable to inhaled prostacyclin. The average cost for inhaled prostacyclin was 150 US dollars per day. Compared with nitric oxide, which costs 3000 US dollars per day, the potential cost savings over this period were 681,686 US dollars.
Inhaled prostacyclin seems to be a safe and effective pulmonary vasodilator for cardiothoracic surgical patients with pulmonary hypertension, refractory hypoxemia, or right heart dysfunction. Overall, inhaled prostacyclin significantly decreases mean pulmonary artery pressures without altering the mean arterial pressure. Compared with nitric oxide, there is no special equipment required for administration or toxicity monitoring, and the cost savings are substantial.
Worldwide, the occurrence of hypertension is the highest in the African WHO Region where 46% of adults above the age of 24years suffer from hypertension. This study was undertaken to document the ...plants used by lay persons in a rural community for the treatment of hypertension, and to determine to what extent they use these plants concurrently with prescribed drugs for hypertension. A total of one hundred lay people with knowledge on antihypertension plants were interviewed using structured questionnaires. Information regarding vernacular plant names, plant parts used, preparation, and dosages was collected, as well as some health information with reference to hypertension. It was found that a total of 28 plant species were used singularly or in 17 different plant combinations in decoctions to treat hypertension. Twenty plant species have never been documented before for the treatment of hypertension. The species most used were: Momordica balsamina (by 44 interviewees), Aloe marlothii (32), Hypoxis hemerocallidea (17), Musa acuminata (10), Strychnos madagascariensis (10), and Senecio serratuloides (9). Thirty-one of the 50 people who had been diagnosed with hypertension were supplementing their prescribed hypertension drugs with medicinal plants. None of them had revealed to their healthcare practitioners that they were also using herbal medicines. Although none of the interviewees were aware of the possible consequences of drug interactions, they were mindful of some side effects caused by the medicinal plants they used for the treatment of hypertension. According to the majority of the interviewees, hypertension is caused by unhappiness and stress. Information from the community was cited as their main source of which plants to use to treat hypertension. It is clear from this survey that medicinal plant remedies play a vital role in the treatment of not just communicable diseases but also in the treatment of chronic ailments like hypertension by the lay persons in this deep rural area. The findings suggested that there is no awareness of the risks that may accompany the simultaneous use of conventional medication and medicinal plants. There is a definitive need to educate health practitioners and patients of the risks they are taking in using both prescribed hypertension drugs and medicinal plants.
•Twenty eight plant species were recorded to treat hypertension.•The most mentioned species are Momordica balsamina and Aloe marlothii.•Concurrent use of prescribed hypertension drugs and medicinal plants.•Unhappiness is believed to be the cause of hypertension.
The implication of invertebrates found in drinking water distribution networks to public health is of concern to water utilities. Previous studies have shown that the bacteria associated with the ...invertebrates could be potentially pathogenic to humans. This study investigated the level and identity of bacteria commonly associated with invertebrates collected from the drinking water treatment systems as well as from the main pipelines leaving the treatment works. On all sampling occasions bacteria were isolated from the invertebrate samples collected. The highest bacterial counts were observed for the samples taken before filtration as was expected. There were, however, indications that optimal removal of invertebrates from water did not always occur. During the investigation, 116 colonies were sampled for further identification. The isolates represent several bacterial genera and species that are pathogenic or opportunistic pathogens of humans. Diarrhoea, meningitis, septicaemia and skin infections are among the diseases associated with these organisms. The estimated number of bacteria that could be associated with a single invertebrate (as based on average invertebrate numbers) could range from 10 to 4000 bacteria per organism. It can, therefore, be concluded that bacteria associated with invertebrates might under the worst case scenario pose a potential health risk to water users. In the light of the above findings it is clear that invertebrates in drinking water should be controlled at levels as low as technically and economically feasible.
Geophagia, a form of pica, has been shown to be widely practised in sub-Saharan Africa, especially among pregnant women.
To assess the prevalence of geophagia and examine exposure to selected metals ...and associated risk factors in women attending an antenatal clinic at Rahima Moosa Mother and Child Hospital, Johannesburg, South Africa, during June and July 2010.
We conducted a cross-sectional study on a convenience sample of 307 pregnant women, ranging in age from 18 to 46 years. Structured interviews were conducted to understand geophagia practices. Blood samples were collected to determine haemoglobin values and concentrations of arsenic, cadmium, mercury and lead. Statistical analyses using the χ2 test, Wilcoxon's rank-sum test and logistic regression analyses were performed as appropriate.
Mean parity was 1.4 and the mean (standard deviation) gestational age 30.3 (6.0) weeks. Geophagia was reported by 60 women (19.5%), and the majority purchased soil from street vendors (83.3%). The prevalence of anaemia in the study sample was 16.9% (95% confidence interval 13.1 - 21.6%). Geophagic women had significantly higher blood lead levels than non-geophagic women (2.1 v. 1.4 µg/dl; p<0.001). Anaemia, the use of African traditional medicines and craving of non-nutritive substances in a previous pregnancy were associated with geophagia.
Geophagia is practised by a considerable proportion of pregnant women in Johannesburg, especially migrant women. Greater vigilance in respect of pica, especially geophagia, may be needed as part of antenatal care programmes to avoid potentially detrimental health effects of the practice.
Abattoir workers are liable to zoonotic infections from animals and animal products, primarily to diseases with asymptomatic and chronic clinical manifestations in animals, such as brucellosis. No ...published reports exist on the seroprevalence of brucellosis in abattoir workers in South Africa. Therefore, this cross-sectional study was conducted to estimate the occurrence and risk factors for
exposure in abattoir workers in Gauteng Province. A total of 103 abattoir workers and managers from 6 abattoirs, where brucellosis-positive slaughtered cattle and sheep were previously detected, were interviewed and tested with serological assays using the Rose Bengal test (RBT), BrucellaCapt, and IgG-ELISA. A pre-tested questionnaire was administered to consenting respondents to obtain information on risk factors for brucellosis. Of the 103 respondents tested, the distribution of female and male workers was 16 (15.5%) and 87 (84.5%), respectively. The seroprevalence for exposure to brucellosis was 21/103 (20.4%, 95%CI: 13.1-29.5) using a combination of RBT, BrucellaCapt, or IgG-ELISA. For test-specific results, seroprevalences by RBT, BrucellaCapt, and IgG-ELISA were 13/103 (12.6%, 95%CI: 6.9-20.6), 9/103 (8.74%, 95%CI: 4.1-15.9), and 18/103 (17.5%, 95%CI: 10.7-26.2), respectively. Low-throughput abattoirs were identified as associated risks, as 29.3% of workers were seropositive compared with 12.7% of workers in high-throughput abattoirs, which highlights that direct contact at abattoirs poses higher risk to workers than indirect and direct contact outside abattoirs. This study confirms the occurrence of
spp. antibodies among abattoir workers in South Africa, possibly due to occupational exposure to
spp., and highlights the occupational hazard to workers. Furthermore, findings underscore that abattoir facilities can serve as points for active and passive surveillance for indicators of diseases of public health importance. We recommend periodic implementation of brucellosis testing of abattoir workers country-wide to establish baseline data for informing appropriate preventive practices and reducing the potential burden of infection rates among these high-risk workers.
The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population ...because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.
ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.
The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.
This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.
NCT03044899.
Activating mutations in the human KCNJ11 gene, encoding the pore-forming subunit (Kir6.2) of the ATP-sensitive potassium (K(ATP)) channel, are one cause of neonatal diabetes mellitus. In a few ...patients, KCNJ11 mutations cause a triad of developmental delay, epilepsy, and neonatal diabetes (DEND syndrome). The aim of this study was to determine the clinical effects, functional cause, and sensitivity to sulfonylurea treatment of a novel KCNJ11 mutation producing DEND syndrome.
We screened the DNA of a 3-year-old patient with neonatal diabetes, severe developmental delay, and therapy-resistant epilepsy for mutations in KCNJ11. We carried out electrophysiologic analysis of wild-type and mutant K(ATP) channels heterologously expressed in Xenopus oocytes.
We identified a novel Kir6.2 mutation (I167L) causing DEND syndrome. Functional analysis showed both homomeric and heterozygous mutant channels were less inhibited by MgATP leading to an increase in whole-cell K(ATP) currents. This effect was due to an increase in the intrinsic open probability. Heterozygous channels were strongly inhibited by the sulfonylurea tolbutamide. Treatment of the patient with the sulfonylurea glibenclamide not only enabled insulin therapy to be stopped, but also resulted in improvement in epilepsy and psychomotor abilities.
We report a case of developmental delay, epilepsy, and neonatal diabetes (DEND) syndrome that shows neurologic improvement with sulfonylurea therapy. Early recognition of patients with DEND syndrome may have considerable therapeutic benefit for the patient.
The radiation environment at the Martian surface is, apart from occasional solar energetic particle events, dominated by galactic cosmic radiation, secondary particles produced in their interaction ...with the Martian atmosphere and albedo particles from the Martian regolith. The highly energetic primary cosmic radiation consists mainly of fully ionized nuclei creating a complex radiation field at the Martian surface. This complex field, its formation and its potential health risk posed to astronauts on future manned missions to Mars can only be fully understood using a combination of measurements and model calculations. In this work the outcome of a workshop held in June 2016 in Boulder, CO, USA is presented: experimental results from the Radiation Assessment Detector of the Mars Science Laboratory are compared to model results from GEANT4, HETC–HEDS, HZETRN, MCNP6, and PHITS. Charged and neutral particle spectra and dose rates measured between 15 November 2015 and 15 January 2016 and model results calculated for this time period are investigated.
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