Response to recharge variation of thin rainwater lenses and their mixing zone with underlying saline groundwater

In coastal zones with saline groundwater, fresh groundwater lenses may form due to infiltration of rain water. The thickness of both the lens and the mixing zone, determines fresh water availability for plant growth. Due to recharge variation, the thickness of the lens and the mixing zone are not constant, which may adversely affect agricultural and natural vegetation if saline water reaches the root zone during the growing season. In this paper, we study the response of thin lenses and their mixing zone to variation of recharge. The recharge is varied using sinusoids with a range of amplitudes and frequencies. We vary lens characteristics by varying the Rayleigh number and Mass flux ratio of saline and fresh water, as these dominantly influence the thickness of thin lenses and their mixing zone. Numerical results show a linear relation between the normalised lens volume and the main lens and recharge characteristics, enabling an empirical approximation of the variation of lens thickness. Increase of the recharge amplitude causes increase and the increase of recharge frequency causes a decrease in the variation of lens thickness. The average lens thickness is not significantly influenced by these variations in recharge, contrary to the mixing zone thickness. The mixing zone thickness is compared to that of a Fickian mixing regime. A simple relation between the travelled distance of the centre of the mixing zone position due to variations in recharge and the mixing zone thickness is shown to be valid for both a sinusoidal recharge variation and actual records of daily recharge data. Starting from a step response function, convolution can be used to determine the effect of variable recharge in time. For a sinusoidal curve, we can determine delay of lens movement compared to the recharge curve as well as the lens amplitude, derived from the convolution integral. Together the proposed equations provide us with a first order approximation of lens characteristics using basic lens and recharge parameters without the use of numerical models. This enables the assessment of the vulnerability of any thin fresh water lens on saline, upward seeping groundwater to salinity stress in the root zone

Optimal clinical management of children receiving ketogenic parenteral nutrition: a clinical practice guide

AIM: To give evidence-based recommendations on the application of ketogenic diet parenteral nutrition (KD-PN) in emergency situations. METHOD: An international group of experts (n=14) researched the literature and distributed a survey among 150 expert centers. International accepted guidelines (European Society for Clinical Nutrition and Metabolism/European Society for Paediatric Gastroenterology Hepatology and Nutrition and the American Society for Parenteral and Enteral Nutrition) and handbooks for parenteral nutrition were considered general standards of care. RESULTS: In the literature, we identified 35 reports of patients treated by KD-PN. International guidelines and handbooks provided some conflicting information. Twenty-four expert teams from nine countries responded to the survey, reflecting the limited clinical experience. INTERPRETATION: This paper highlights 23 consensus-based recommendations for safe and effective KD-PN (e.g. diet initiation, calculation, application, monitoring, and evaluation) based on the best evidence available and expert opinions. WHAT THIS PAPER ADDS: In acute settings, ketogenic diet therapy (KDT) can be administered parenterally. Parenteral administration of KDT should be started only at the intensive care unit. Initiate ketogenic parenteral nutrition stepwise to the highest ratio possible with the lowest level of complications. Evaluate the risk-benefit ratio of parenteral administration continuously. Restart enteral feeding as soon as appropriate

Optimal clinical management of children receiving ketogenic parenteral nutrition: a clinical practice guide

AIM To give evidence-based recommendations on the application of ketogenic diet parenteral nutrition (KD-PN) in emergency situations. METHOD An international group of experts (n=14) researched the literature and distributed a survey among 150 expert centers. International accepted guidelines (European Society for Clinical Nutrition and Metabolism/European Society for Paediatric Gastroenterology Hepatology and Nutrition and the American Society for Parenteral and Enteral Nutrition) and handbooks for parenteral nutrition were considered general standards of care. RESULTS In the literature, we identified 35 reports of patients treated by KD-PN. International guidelines and handbooks provided some conflicting information. Twenty-four expert teams from nine countries responded to the survey, reflecting the limited clinical experience. INTERPRETATION This paper highlights 23 consensus-based recommendations for safe and effective KD-PN (e.g. diet initiation, calculation, application, monitoring, and evaluation) based on the best evidence available and expert opinions

Ketogenic diet treatment as adjuvant to standard treatment of glioblastoma multiforme: a feasibility and safety study

Background: High-grade glioma cells consume mainly glucose and cannot compensate for glucose restriction. Apoptosis may potentially occur under carbohydrate restriction by a ketogenic diet (KD). We explored the feasibility and safety of KD during standard treatment of chemoradiation in patients with glioblastoma multiforme. Methods: A full liquid KD induced ketosis within 2 weeks before start of chemoradiation. After 6 weeks, the KD was modified with solid foods and medium-chain-triglyceride emulsions and used for an additional 6 weeks while maintaining ketosis. During the total study period (14 weeks), feasibility, safety, coping (both patient and partner), quality of life (QoL), neurological functioning and impairment were measured. Overall survival was analyzed with actuarial estimates. Results: Eleven patients started the study protocol, nine reached ketosis and six (67%) completed the study. Severe adverse effects did not occur. The majority of coping scores ranged from 3 to 6 on a 10-point scale at all timepoints; QoL, neurological functioning, and impairment did not essentially change over time; overall survival ranged between 9.8 and 19.0 months. Conclusion: KD was feasible and safe as an adjuvant to standard chemoradiation treatment of glioblastoma multiforme. A supportive partner and intensive counseling were essential for coping. Future research should identify possible beneficial effects on overall survival. Clinical trial registration: Netherlands Trial Registry: NTR5167 (registration date 29-01-2015), http://www.trialregister.nl/trialreg/index.asp

Qualitative and quantitative detection of SARS-CoV-2 RNA in untreated wastewater in Western Cape Province, South Africa

Recent studies have shown that the detection of SARS-CoV-2 genetic material in wastewater may provide the basis for a surveillance system to track the environmental dissemination of this virus in communities. An effective wastewater-based epidemiology (WBE) system may prove critical in South Africa (SA), where health systems infrastructure, testing capacity, personal protective equipment and human resource capacity are constrained. In this proof-of-concept study, we investigated the potential of SARS-CoV-2 RNA surveillance in untreated wastewater as the basis for a system to monitor COVID-19 prevalence in the population, an early warning system for increased transmission, and a monitoring system to assess the effectiveness of interventions. The laboratory confirmed the presence (qualitative analysis) and determined the RNA copy number of SARS-CoV-2 viral RNA by reverse transcription polymerase chain reaction (quantitative) analysis from 24-hour composite samples collected on 18 June 2020 from five wastewater treatment plants in Western Cape Province, SA. The study has shown that a WBE system for monitoring the status and trends of COVID-19 mass infection in SA is viable, and its development and implementation may facilitate the rapid identification of hotspots for evidence-informed interventions

Trends in poverty and inequality since the political transition

Using a constructed data series and another data series based on the All Media and Products surveys (AMPS), this paper explores trends in poverty and income distribution over the post-transition period. To steer clear of an unduly optimistic conclusion, assumptions are chosen that would tend to show the least decline in poverty. Whilst there were no strong trends in poverty for the period 1995 to 2000, both data series show a considerable decline in poverty after 2000, particularly in the period 2002-2004. Poverty dominance testing shows that this decline is independent of the poverty line chosen or whether the poverty headcount, the poverty ratio or the poverty severity ratio are used as measure. We find likely explanations for this strong and robust decline in poverty in the massive expansion of the social grant system as well as possibly in improved job creation in recent years. Whilst the collective income of the poor (using our definition of poverty) was only R27 billion in 2000, the grants (in constant 2000 Rand values) have expanded by R22 billion since. Even if the grants were not well targeted at the poor (and in the past they have been), a large proportion of this spending must have reached the poor, thus leaving little doubt that poverty must have declined substantially

Gastric cancers of Western European and African patients show different patterns of genomic instability

<p>Abstract</p> <p>Background</p> <p>Infection with <it>H. pylori </it>is important in the etiology of gastric cancer. Gastric cancer is infrequent in Africa, despite high frequencies of <it>H. pylori </it>infection, referred to as the African enigma. Variation in environmental and host factors influencing gastric cancer risk between different populations have been reported but little is known about the biological differences between gastric cancers from different geographic locations. We aim to study genomic instability patterns of gastric cancers obtained from patients from United Kingdom (UK) and South Africa (SA), in an attempt to support the African enigma hypothesis at the biological level.</p> <p>Methods</p> <p>DNA was isolated from 67 gastric adenocarcinomas, 33 UK patients, 9 Caucasian SA patients and 25 native SA patients. Microsatellite instability and chromosomal instability were analyzed by PCR and microarray comparative genomic hybridization, respectively. Data was analyzed by supervised univariate and multivariate analyses as well as unsupervised hierarchical cluster analysis.</p> <p>Results</p> <p>Tumors from Caucasian and native SA patients showed significantly more microsatellite instable tumors (p < 0.05). For the microsatellite stable tumors, geographical origin of the patients correlated with cluster membership, derived from unsupervised hierarchical cluster analysis (p = 0.001). Several chromosomal alterations showed significantly different frequencies in tumors from UK patients and native SA patients, but not between UK and Caucasian SA patients and between native and Caucasian SA patients.</p> <p>Conclusions</p> <p>Gastric cancers from SA and UK patients show differences in genetic instability patterns, indicating possible different biological mechanisms in patients from different geographical origin. This is of future clinical relevance for stratification of gastric cancer therapy.</p

Recommendations for the diagnosis and management of vaccine-induced immune thrombotic thrombocytopenia

There have recently been safety concerns regarding an increased risk of vaccine-induced immune thrombotic thrombocytopenia (VITT) following administration of SARS-CoV-2 adenoviral vector vaccines. The Southern African Society of Thrombosis and Haemostasis reviewed the emerging literature on this idiosyncratic complication. A draft document was produced and revised by consensus agreement by a panel of professionals from various specialties. The recommendations were adjudicated by independent international experts to avoid local bias. We present concise, practical guidelines for the clinical management of VITT

Incidence and prevalence of patellofemoral pain: a systematic review and meta-analysis

Background: Patellofemoral pain is considered one of the most common forms of knee pain, affecting adults, adolescents, and physically active populations. Inconsistencies in reported incidence and prevalence exist and in relation to the allocation of healthcare and research funding, there is a clear need to accurately understand the epidemiology of patellofemoral pain. Methods: An electronic database search was conducted, as well as grey literature databases, from inception to June 2017. Two authors independently selected studies, extracted data and appraised methodological quality. If heterogeneous, data were analysed descriptively. Where studies were homogeneous, data were pooled through a meta-analysis. Results: 23 studies were included. Annual prevalence for patellofemoral pain in the general population was reported as 22.7%, and adolescents as 28.9%. Incidence rates in military recruits ranged from 9.7 – 571.4/1,000 person-years, amateur runners in the general population at 1080.5/1,000 person-years and adolescents amateur athletes 5.1% - 14.9% over 1 season. One study reported point prevalence within military populations as 13.5%. The pooled estimate for point prevalence in adolescents was 7.2% (95% Confidence Interval: 6.3% - 8.3%), and in female only adolescent athletes was 22.7% (95% Confidence Interval 17.4% - 28.0%). Conclusion: This review demonstrates high incidence and prevalence levels for patellofemoral pain. Within the context of this, and poor long term prognosis and high disability levels, PFP should be an urgent research priority