Overriding water table control on managed peatland greenhouse gas emissions.

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland3-5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems6. Here we report eddy covariance data for carbon dioxide from 16 locations and static chamber measurements for methane from 41 locations in the UK and Ireland. We combine these with published data from sites across all major peatland biomes. We find that the mean annual effective water table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 centimetres of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year global warming potentials) by the equivalent of at least 3 tonnes of CO2 per hectare per year, until WTDe is less than 30 centimetres. Raising water levels further would continue to have a net cooling effect until WTDe is within 10 centimetres of the surface. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1 per cent of global anthropogenic emissions.

Establishment of local wastewater-based surveillance programmes in response to the spread and infection of COVID-19 - case studies from South Africa, the Netherlands, Turkey and England.

The COVID-19 pandemic has resulted in over 340 million infection cases (as of 21 January 2022) and more than 5.57 million deaths globally. In reaction, science, technology and innovation communities across the globe have organised themselves to contribute to national responses to COVID-19 disease. A significant contribution has been from the establishment of wastewater-based epidemiological (WBE) surveillance interventions and programmes for monitoring the spread of COVID-19 in at least 55 countries. Here, we examine and share experiences and lessons learnt in establishing such surveillance programmes. We use case studies to highlight testing methods and logistics considerations associated in scaling the implementing of such programmes in South Africa, the Netherlands, Turkey and England. The four countries were selected to represent different regions of the world and the perspective based on the considerable progress made in establishing and implementing their national WBE programmes. The selected countries also represent different climatic zones, economies, and development stages, which influence the implementation of national programmes of this nature and magnitude. In addition, the four countries' programmes offer good experiences and lessons learnt since they are systematic, and cover extensive areas, disseminate knowledge locally and internationally and partnered with authorities (government). The programmes also strengthened working relations and partnerships between and among local and global organisations. This paper shares these experiences and lessons to encourage others in the water and public health sectors on the benefits and value of WBE in tackling SARS-CoV-2 and related future circumstances.

The association of HIV and cocaine use to cigarette smoking in the context of depression and perceived stress.

Mental well-being can contribute to cigarette smoking and negatively impact disease progression among people living with HIV (PLWH). This study examined potential associations between cocaine use (COC), depression, and HIV status in predicting cigarette smoking; hypothesizing that depression would be highest in cocaine users and predict cigarette smoking. An exploratory analysis including stress was also examined as a potential predictor of cigarette use. More than half of the sample (65%) endorsed smoking at some point in the past, and 52% endorsed being current smokers at the time of the study. Smokers were most likely to be cocaine users (87.1%), cocaine using PLWH (74.3%), or PLWH (36.6%). Neither HIV status (χ2(1) = 1.5, p = .221), perceived stress (χ2(1) = 0.75 p = .386), nor depressive symptomatology (χ2(1) = 1.2, p = .274) were related to smoking. Non-cocaine users were approximately 95.4% less likely to smoke than cocaine users, controlling for all other variables. Overall, cocaine use was the greatest predictor of cigarette smoking and quantity of cigarettes smoked. Perceived stress and depression were not associated with cigarette smoking in the sample. Future interventions targeting cigarette use should include a cocaine-related component to encourage smoking cessation among this high-risk group.

A Bayesian Analysis of Prenatal Maternal Factors Predicting Nonadherence to Infant HIV Medication in South Africa.

While efforts to prevent mother-to-child transmission of HIV been successful in some districts in South Africa, rates remain unacceptably high in others. This study utilized Bayesian logistic regression to examine maternal-level predictors of adherence to infant nevirapine prophylaxis, including intimate partner violence, maternal adherence, HIV serostatus disclosure reaction, recency of HIV diagnosis, and depression. Women (N = 303) were assessed during pregnancy and 6 weeks postpartum. Maternal adherence to antiretroviral therapy during pregnancy predicted an 80% reduction in the odds of infant nonadherence [OR 0.20, 95% posterior credible interval (.11, .38)], and maternal prenatal depression predicted an increase [OR 1.04, 95% PCI (1.01, 1.08)]. Results suggest that in rural South Africa, failure to provide medication to infants may arise from shared risk factors with maternal nonadherence. Intervening to increase maternal adherence and reduce depression may improve adherence to infant prophylaxis and ultimately reduce vertical transmission rates.

Critical review of the impacts of grazing intensity on soil organic carbon storage and other soil quality indicators in extensively managed grasslands.

Livestock grazing intensity (GI) is thought to have a major impact on soil organic carbon (SOC) storage and soil quality indicators in grassland agroecosystems. To critically investigate this, we conducted a global review and meta-analysis of 83 studies of extensive grazing, covering 164 sites across different countries and climatic zones. Unlike previous published reviews we normalized the SOC and total nitrogen (TN) data to a 30 cm depth to be compatible with IPCC guidelines. We also calculated a normalized GI and divided the data into four main groups depending on the regional climate (dry warm, DW; dry cool, DC; moist warm, MW; moist cool, MC). Our results show that taken across all climatic zones and GIs, grazing (below the carrying capacity of the systems) results in a decrease in SOC storage, although its impact on SOC is climate-dependent. When assessed for different regional climates, all GI levels increased SOC stocks under the MW climate (+7.6%) whilst there were reductions under the MC climate (-19%). Under the DW and DC climates, only the low (+5.8%) and low to medium (+16.1%) grazing intensities, respectively, were associated with increased SOC stocks. High GI significantly increased SOC for C4-dominated grassland compared to C3-dominated grassland and C3-C4 mixed grasslands. It was also associated with significant increases in TN and bulk density but had no effect on soil pH. To protect grassland soils from degradation, we recommend that GI and management practices should be optimized according to climate region and grassland type (C3, C4 or C3-C4 mixed).

How changing root system architecture can help tackle a reduction in soil phosphate (P) levels for better plant P acquisition.

The readily available global rock phosphate (P) reserves may run out within the next 50-130 years, causing soils to have a reduced P concentration which will affect plant P uptake. Using a combination of mathematical modelling and experimental data, we investigated potential plant-based options for optimizing crop P uptake in reduced soil P environments. By varying the P concentration within a well-mixed agricultural soil, for high and low P (35.5-12.5 mg L(-1) respectively using Olsen's P index), we investigated branching distributions within a wheat root system that maximize P uptake. Changing the root branching distribution from linear (evenly spaced branches) to strongly exponential (a greater number of branches at the top of the soil) improves P uptake by 142% for low-P soils when root mass is kept constant between simulations. This causes the roots to emerge earlier and mimics topsoil foraging. Manipulating root branching patterns, to maximize P uptake, is not enough on its own to overcome the drop in soil P from high to low P. Further mechanisms have to be considered to fully understand the impact of P reduction on plant development.

Effect of subcutaneous insulin detemir on glucose flux and lipolysis during hyperglycaemia in people with type 1 diabetes.

AIMS: To investigate, using a novel non-steady-state protocol, the differential effects of subcutaneous (s.c.) detemir and NPH insulin on glucose flux and lipid metabolism after insulin withdrawal. METHODS: After a period of insulin withdrawal resulting in whole-blood glucose concentration of 7 mmol/l, 11 participants (five men, mean age 41.0 years, mean body mass index 25 kg/m(2)) with type 1 diabetes (mean glycated haemoglobin concentration 57 mmol/mol, mean diabetes duration 14 years) received 0.5 units per kg body weight s.c. insulin detemir or NPH insulin in random order. Stable isotopes of glucose and glycerol were infused intravenously throughout the study protocol. RESULTS: Glucose concentration decreased after insulin treatment as a result of suppression of endogenous glucose production, which occurred to a similar extent with both detemir and NPH insulin. The rate of glucose disappearance (Rd) was not increased significantly with either type of insulin. When the effect of detemir and NPH insulin on glucose flux at glucose concentrations between 9 and 6 mmol/l was examined, glucose rate of appearance (Ra) was similar with the two insulins; however, glucose Rd was greater with NPH insulin than with detemir at glucose concentrations of 8.0, 8.5, 7.0 and 6.0 mmol/l (p < 0.05) The percentage change in glycerol Ra, a measure of lipolysis, was greater in the NPH group than in the detemir group (p = 0.04). CONCLUSIONS: The results of the study are consistent with the hypothesis that detemir has a lesser effect on the periphery, as evidenced by a lesser effect on peripheral glucose uptake at specific glucose concentrations.

Effect of subcutaneous insulin detemir on glucose flux, lipolysis and electroencephalography in type 1 diabetes.

The aim of the present study was to investigate the effects of subcutaneous detemir on glucose flux, lipid metabolism and brain function. Twelve people with type 1 diabetes received, in random order, 0.5 units/kg body weight detemir or NPH insulin. Glucose concentration was clamped at 5 mmol/l then increased to 10 mmol/l. Glucose production rate (glucose Ra), glucose uptake (glucose Rd) and glycerol production (glycerol Ra) were measured with a constant intravenous infusion of [6,6(2) H(2)]glucose and [(2)H(5)]glycerol. Electroencephalography direct current (DC) and alternating current (AC) potentials were measured. While detemir induced similar effects on glucose Ra, glucose Rd and glycerol Ra during euglycaemia compared with NPH, it triggered a distinct negative shift in DC potentials, with a significant treatment effect in frontal cerebrocortical channels (p < 0.001). AC spectral power showed significant differences in theta and alpha frequencies during euglycaemia (p = 0.03). Subcutaneous detemir exerts different effects on brain function when compared with NPH in people with type 1 diabetes. This may be an important mechanism behind the limitation of weight gain with detemir.

Hepatoselectivity and the evolution of insulin.

In spite of major developments in insulin production, purification, pharmaceutical formulation and methods of delivery, problems remain both in the day to day management of insulin-treated diabetes and with regard to its long-term complications. The risks of hypoglycaemia and weight gain are major concerns particularly for the patient, and the persistence of microvascular and premature macrovascular complications as the main causes of morbidity and mortality in both type 1 and type 2 diabetes is a constant reminder that our therapeutic and management strategies are inadequate. One clear and striking difference between currently available insulin treatments and normal physiology is the relative difference in exposure to insulin of the liver versus peripheral tissues. Hepatoselective insulin analogues have the potential to restore the normal hepatic to peripheral gradient in insulin action. Here, we discuss the possible therapeutic potential that such analogues may have over currently available insulin preparations. These benefits could include a lower risk of hypoglycaemia, less weight gain and a potential reduction in microvascular and macrovascular complications. We explore the evolution of insulin with hepatoselectivity in mind and possible strategies to create hepatoselective insulins.

A quantitative risk assessment for the safety of carcase storage systems for scrapie infected farms.

AIMS: To determine the risk associated with the use of carcase storage vessels on a scrapie infected farm. METHODS AND RESULTS: A stochastic quantitative risk assessment was developed to determine the rate of accumulation and fate of scrapie in a novel low-input storage system. For an example farm infected with classical scrapie, a mean of 10(3·6) Ovine Oral ID50 s was estimated to accumulate annually. Research indicates that the degradation of any prions present may range from insignificant to a magnitude of one or two logs over several months of storage. CONCLUSIONS: For infected farms, the likely partitioning of remaining prion into the sludge phase would necessitate the safe operation and removal of resulting materials from these systems. If complete mixing could be assumed, on average, the concentrations of infectivity are estimated to be slightly lower than that measured in placenta from infected sheep at lambing. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first quantitative assessment of the scrapie risk associated with fallen stock on farm and provides guidance to policy makers on the safety of one type of storage system and the relative risk when compared to other materials present on an infected farm.

Effectiveness of cooking to reduce norovirus and infectious F-specific RNA bacteriophage concentrations in Mytilus edulis.

AIMS: The aim of this study was to determine if domestic cooking practices can reduce concentrations of norovirus (NoV) and F-specific RNA (FRNA) bacteriophage in experimentally contaminated mussels. METHODS AND RESULTS: Mussels (n = 600) contaminated with NoV and FRNA bacteriophage underwent four different cooking experiments performed in triplicate at ~70°C and >90°C. Concentrations of infectious FRNA bacteriophage (using a plaque assay) were compared with concentrations of FRNA bacteriophage and NoV determined using a standardised RT-qPCR. Initial concentrations of infectious FRNA bacteriophage (7·05 log10  PFU g(-1) ) in mussels were not significantly reduced in simmering water (~70°C); however, cooking at higher temperatures (>90°C) reduced infectious FRNA bacteriophage to undetected levels within 3 min. Further investigation determined the time required for a 1-log reduction of infectious FRNA bacteriophage at 90°C to be 42 s therefore a >3-log reduction in infectious virus can be obtained by heating mussel digestive tissue to 90°C for 126 s. CONCLUSIONS: Domestic cooking practices based on shell opening alone do not inactivate infectious virus in mussels, however, cooking mussels at high temperatures is effective to reduce infectious virus concentrations and the risk of illness in consumers. SIGNIFICANCE AND IMPACT OF THE STUDY: The data will contribute towards evidence-based cooking recommendations for shellfish to provide a safe product for human consumption.

A mathematical model of water and nutrient transport in xylem vessels of a wheat plant.

At a time of increasing global demand for food, dwindling land and resources, and escalating pressures from climate change, the farming industry is undergoing financial strain, with a need to improve efficiency and crop yields. In order to improve efficiencies in farming, and in fertiliser usage in particular, understanding must be gained of the fertiliser-to-crop-yield pathway. We model one aspect of this pathway; the transport of nutrients within the vascular tissues of a crop plant from roots to leaves. We present a mathematical model of the transport of nutrients within the xylem vessels in response to the evapotranspiration of water. We determine seven different classes of flow, including positive unidirectional flow, which is optimal for nutrient transport from the roots to the leaves; and root multidirectional flow, which is similar to the hydraulic lift process observed in plants. We also investigate the effect of diffusion on nutrient transport and find that diffusion can be significant at the vessel termini especially if there is an axial efflux of nutrient, and at night when transpiration is minimal. Models such as these can then be coupled to whole-plant models to be used for optimisation of nutrient delivery scenarios.

Can an interprofessional education tool improve healthcare professional confidence, knowledge and quality of inpatient diabetes care: a pilot study?

AIMS: To conduct a pilot study evaluation of an interprofessional education tool that could improve healthcare professional confidence, knowledge and quality of inpatient diabetes care. METHODS: Diabetes specialists designed an education tool for use in the hospital environment to educate qualified pharmacists, nurses, healthcare assistants and junior doctors. The interprofessional learning enabled professionals to learn from and about each other. The education tool was piloted at four hospitals. Diabetes specialists delivered the education programme to 31 healthcare professionals over 8 h either as three individual teaching blocks or a whole day. Healthcare professionals completed a multiple choice questionnaire before and after the education intervention to evaluate acquisition of knowledge. The maximum score was 20. Confidence was evaluated using categorical questions. Diabetes specialists used a clinical audit form before and after the education programme, to evaluate the quality of diabetes care. RESULTS: Healthcare professional's confidence improved from 58 to 94% (P < 0.05) and knowledge improved from 12.4 ± 0.6 to 15.0 ± 0.6 (mean ± sem, P < 0.05). There was a reduction in management errors from 74 to 44% (P < 0.05) and improvement in appropriate blood glucose monitoring from 67 to 92% (P < 0.05). The number of patients with documented foot assessment improved from15 to 33% (P < 0.05). Improvement in the number of appropriate diabetes referrals and reduction in prescribing errors did not reach statistical significance. CONCLUSION: The education tool improved healthcare professional confidence, knowledge and may improve the quality of inpatient diabetes care.

Management of raised glucose, a clinical decision tool to reduce length of stay of patients with hyperglycaemia.

OBJECTIVE: To assess whether the introduction of a management of raised glucose clinical decision tool could improve assessment of patients with hyperglycaemia by non-specialist physicians, leading to early discharge and improved quality of inpatient care. METHODS: Participants were adults aged 18 years or over presenting to the Medical Assessment Unit with a capillary blood glucose level > 11.1 mmol/l. Phase 1 of the study (phase 1) evaluated current clinical practice and potential impact of the clinical decision tool. Phase 2 evaluated the effectiveness of the management of raised glucose tool in clinical practice. Primary outcome measures were inpatient length of stay and same-calendar-day discharges. Secondary outcome measures were diabetes specialist input, patient assessment, intravenous insulin infusion use and patient satisfaction. RESULTS: Implementation of the management of raised glucose clinical decision tool allowed safe, same-calendar-day discharges of 40% of patients with hyperglycaemia as their primary reason for attendance. Median length of stay was lower in the phase 1 than in phase 2 (1.0 vs. 3.5 days, P < 0.01). Early discharge did not result in an increase in readmissions. There was improvement in hyperglycaemia assessment for all patients (P < 0.01), a reduction in the use of intravenous insulin infusions (P < 0.01) and high level of patient satisfaction. CONCLUSION: The management of raised glucose clinical decision tool resulted in a significant increase in the number of same-calendar-day discharges and reduction in hospital length of stay without adverse impact on readmission rates. Additionally, the tool was associated with improvements in inpatient diabetes care and patient satisfaction.

Insulin degludec improves glycaemic control with lower nocturnal hypoglycaemia risk than insulin glargine in basal-bolus treatment with mealtime insulin aspart in Type 1 diabetes (BEGIN(®) Basal-Bolus Type 1): 2-year results of a randomized clinical trial.

AIMS: The goal of this study was to compare the long-term safety and efficacy of the basal insulin analogue, insulin degludec with insulin glargine (both with insulin aspart) in Type 1 diabetes, over a 2-year time period. METHODS: This open-label trial comprised a 1-year main trial and a 1-year extension. Patients were randomized to once-daily insulin degludec or insulin glargine and titrated to pre-breakfast plasma glucose values of 3.9-4.9 mmol/l. RESULTS: The rate of nocturnal confirmed hypoglycaemia was 25% lower with insulin degludec than with insulin glargine (P = 0.02). Rates of confirmed hypoglycaemia, severe hypoglycaemia and adverse events, and reductions in glycated haemoglobin and fasting plasma glucose were similar between groups. Despite achieving similar glycaemic control, insulin degludec-treated patients used 12% less basal and 9% less total daily insulin than did insulin glargine-treated patients (P < 0.01). CONCLUSIONS: Long-term basal therapy using insulin degludec in Type 1 diabetes required lower doses and was associated with a 25% lower risk for nocturnal hypoglycaemia than insulin glargine.

Reducing the risk of HIV infection during pregnancy among South African women: a randomized controlled trial.

Mpumalanga Province, South Africa has one of the highest HIV/AIDS diagnosis rates among pregnant women (~29.4%). This study sought to enhance male involvement in pregnancy to increase HIV disclosure, sexual communication, HIV knowledge and reduce unprotected sex. Participants attending Antenatal Clinics (ANC) completed HIV counseling and testing and were enrolled with male partners (n=239 couples, 478 individuals). Twelve ANCs were randomly assigned to provide a prevention of mother-to-child transmission (PMTCT) intervention or the standard of care, health education sessions plus PMTCT. Participants were assessed at baseline and post-intervention (approximately 6-8 weeks post-baseline) on demographics, sexual behavior, HIV-related knowledge, and conflict resolution strategies. Experimental participants increased HIV knowledge, use of negotiation, and decreased intimate partner violence. Additionally, they were more likely to have increased condom use from baseline to post-intervention (OR=5.1, 95% CI=[2.0, 13.3]). Seroconversions in the control condition exceeded experimental (6 vs. 0). HIV serostatus disclosure to partner did not increase over time for men or women within the experimental or control condition. Male involvement in pregnancy may be an important strategy to reduce sexual risk behavior and HIV transmission. Results support the utility of group interventions to enhance communication and HIV knowledge among pregnant couples.

Subclinical infection and asymptomatic carriage of gastrointestinal zoonoses: occupational exposure, environmental pathways, and the anonymous spread of disease.

Asymptomatic carriage of gastrointestinal zoonoses is more common in people whose profession involves them working directly with domesticated animals. Subclinical infections (defined as an infection in which symptoms are either asymptomatic or sufficiently mild to escape diagnosis) are important within a community as unknowing (asymptomatic) carriers of pathogens do not change their behaviour to prevent the spread of disease; therefore the public health significance of asymptomatic human excretion of zoonoses should not be underestimated. However, optimal strategies for managing diseases where asymptomatic carriage instigates further infection remain unresolved, and the impact on disease management is unclear. In this review we consider the environmental pathways associated with prolonged antigenic exposure and critically assess the significance of asymptomatic carriage in disease outbreaks. Although screening high-risk groups for occupationally acquired diseases would be logistically problematical, there may be an economic case for identifying and treating asymptomatic carriage if the costs of screening and treatment are less than the costs of identifying and treating those individuals infected by asymptomatic hosts.

City-wide wastewater genomic surveillance through the successive emergence of SARS-CoV-2 Alpha and Delta variants.

Genomic surveillance of SARS-CoV-2 has provided a critical evidence base for public health decisions throughout the pandemic. Sequencing data from clinical cases has helped to understand disease transmission and the spread of novel variants. Genomic wastewater surveillance can offer important, complementary information by providing frequency estimates of all variants circulating in a population without sampling biases. Here we show that genomic SARS-CoV-2 wastewater surveillance can detect fine-scale differences within urban centres, specifically within the city of Liverpool, UK, during the emergence of Alpha and Delta variants between November 2020 and June 2021. Furthermore, wastewater and clinical sequencing match well in the estimated timing of new variant rises and the first detection of a new variant in a given area may occur in either clinical or wastewater samples. The study's main limitation was sample quality when infection prevalence was low in spring 2021, resulting in a lower resolution of the rise of the Delta variant compared to the rise of the Alpha variant in the previous winter. The correspondence between wastewater and clinical variant frequencies demonstrates the reliability of wastewater surveillance. However, discrepancies in the first detection of the Alpha variant between the two approaches highlight that wastewater monitoring can also capture missing information, possibly resulting from asymptomatic cases or communities less engaged with testing programmes, as found by a simultaneous surge testing effort across the city.