Intensive rainfall recharges tropical groundwaters

Dependence upon groundwater to meet rising agricultural and domestic water needs is expected to increase substantially across the tropics where, by 2050, over half of the world's population is projected to live. Rare, long-term groundwater-level records in the tropics indicate that groundwater recharge occurs disproportionately from heavy rainfalls exceeding a threshold. The ubiquity of this bias in tropical groundwater recharge to intensive precipitation is, however, unknown. By relating available long-term records of stable-isotope ratios of O and H in tropical precipitation (15 sites) to those of local groundwater, we reveal that groundwater recharge in the tropics is near-uniformly (14/15 sites) biased to intensive monthly rainfall, commonly exceeding the ~70th intensity decile. Our results suggest that the intensification of precipitation brought about by global warming favours groundwater replenishment in the tropics. Nevertheless, the processes that transmit intensive rainfall to groundwater systems and enhance the resilience of tropical groundwater storage in a warming world, remain unclear

Recent glacial recession in the Rwenzori Mountains of East Africa due to rising air temperature

Based on field surveys and analyses of optical spaceborne images (LandSat5, LandSat7), we report recent decline in the areal extent of glaciers in the Rwenzori Mountains of East Africa from 2.01 +/- 0.56 km(2) in 1987 to 0.96 +/- 0.34 km(2) in 2003. The spatially uniform loss of glacial cover at lower elevations together with meteorological trends derived from both station and reanalysis data, indicate that increased air temperature is the main driver. Clear trends toward increased air temperatures over the last four decades of similar to 0.5 degrees C per decade exist without significant changes in annual precipitation. Extrapolation of trends in glacial recession since 1906 suggests that glaciers in the Rwenzori Mountains will disappear within the next two decades

Uncertainty in climate change impacts on basin-scale freshwater resources – preface to the special issue: the QUEST-GSI methodology and synthesis of results

This paper presents a preface to this Special Issue on the results of the QUEST-GSI (Global Scale Impacts) project on climate change impacts on catchment-scale water resources. A detailed description of the unified methodology, subsequently used in all studies in this issue, is provided. The project method involved running simulations of catchment-scale hydrology using a unified set of past and future climate scenarios, to enable a consistent analysis of the climate impacts around the globe. These scenarios include "policy-relevant" prescribed warming scenarios. This is followed by a synthesis of the key findings. Overall, the studies indicate that in most basins the models project substantial changes to river flow, beyond that observed in the historical record, but that in many cases there is considerable uncertainty in the magnitude and sign of the projected changes. The implications of this for adaptation activities are discussed

Continuous functions with universally divergent Fourier series on small subsets of the circle

It is shown that quasi all continuous functions on the unit circle have the property that, for many small subsets E of the circle, the partial sums of their Fourier series considered as functions restricted to E exhibit certain universality properties.Comment: 6 page

Cardiomyopathy, familial dilated

Dilated cardiomyopathy (DCM) is a heart muscle disease characterized by ventricular dilatation and impaired systolic function. Patients with DCM suffer from heart failure, arrhythmia, and are at risk of premature death. DCM has a prevalence of one case out of 2500 individuals with an incidence of 7/100,000/year (but may be under diagnosed). In many cases the disease is inherited and is termed familial DCM (FDC). FDC may account for 20–48% of DCM. FDC is principally caused by genetic mutations in FDC genes that encode for cytoskeletal and sarcomeric proteins in the cardiac myocyte. Family history analysis is an important tool for identifying families affected by FDC. Standard criteria for evaluating FDC families have been published and the use of such criteria is increasing. Clinical genetic testing has been developed for some FDC genes and will be increasingly utilized for evaluating FDC families. Through the use of family screening by pedigree analysis and/or genetic testing, it is possible to identify patients at earlier, or even presymptomatic stages of their disease. This presents an opportunity to invoke lifestyle changes and to provide pharmacological therapy earlier in the course of disease. Genetic counseling is used to identify additional asymptomatic family members who are at risk of developing symptoms, allowing for regular screening of these individuals. The management of FDC focuses on limiting the progression of heart failure and controlling arrhythmia, and is based on currently accepted treatment guidelines for DCM. It includes general measures (salt and fluid restriction, treatment of hypertension, limitation of alcohol intake, control of body weight, moderate exercise) and pharmacotherapy. Cardiac resynchronization, implantable cardioverter defibrillators and left ventricular assist devices have progressively expanding usage. Patients with severe heart failure, severe reduction of the functional capacity and depressed left ventricular ejection fraction have a low survival rate and may require heart transplant

Formalising extended finite state machine transition merging

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordModel inference from system traces, e.g. for analysing legacy components or generating security tests for distributed components, is a common problem. Extended Finite State Machine (EFSM) models, managing an internal data state as a set of registers, are particularly well suited for capturing the behaviour of stateful components however existing inference techniques for (E)FSMs lack the ability to infer the internal state and its update functions. In this paper, we present the underpinning formalism for an EFSM inference technique that involves the merging of transitions with updates to the internal data state. Our model is formalised in Isabelle/HOL, allowing for the machine-checked validation of transition merges and system properties

Inference of Extended Finite State Machines

This is the final version. Available from AFP via the link in this recordIn this AFP entry, we provide a formal implementation of a state-merging technique to infer extended finite state machines (EFSMs), complete with output and update functions, from black-box traces. In particular, we define the subsumption in context relation as a means of determining whether one transition is able to account for the behaviour of another. Building on this, we define the direct subsumption relation, which lifts the subsumption in context relation to EFSM level such that we can use it to determine whether it is safe to merge a given pair of transitions. Key proofs include the conditions necessary for subsumption to occur and that subsumption and direct subsumption are preorder relations. We also provide a number of different heuristics which can be used to abstract away concrete values into registers so that more states and transitions can be merged and provide proofs of the various conditions which must hold for these abstractions to subsume their ungeneralised counterparts. A Code Generator setup to create executable Scala code is also defined

A Formal Model of Extended Finite State Machines

This is the final version. Available from AFP via the link in this recordIn this AFP entry, we provide a formalisation of extended finite state machines (EFSMs) where models are represented as finite sets of transitions between states. EFSMs execute traces to produce observable outputs. We also define various simulation and equality metrics for EFSMs in terms of traces and prove their strengths in relation to each other. Another key contribution is a framework of function definitions such that LTL properties can be phrased over EFSMs. Finally, we provide a simple example case study in the form of a drinks machine

Faecal contamination pathways of shallow groundwater in low-income urban areas: implications for water resource planning and management

Shallow groundwater is vulnerable to faecal contamination, especially in low-income urban areas where use of on-site sanitation facilities is high. This paper explores statistical relationships between potential factors influencing contaminant pathways (i.e., variables) and observed faecal contamination of shallow groundwater, represented by nitrate concentrations and counts of Escherichia coli (i.e., response function) in a small, growing town in Uganda over dry and wet seasons in 2018 and 2019. A statistically significant (p = 0.004) multiple linear regression model from dry-season E. coli counts in 2018 identifies medium sanitary risk levels and modes of construction as significant pathways (p = 0.01). Water source depth (10 m) to a pit latrine were also significant (p<0.05) in both hydrogeological formations. No significant linear regression models were established for NO3 during both seasons due to low pH and rapid infiltration velocities; incon-sistent sample timing during the wet season impaired the significance of the statistical models of E. coli counts. We show that modes of construction of water sources and pit latrines play key roles in determining the quality of the shallow groundwater in urban environments. Greater emphasis is therefore required to improve the functionality and sustainability of on-site water sources and pit latrines