The soft part of the Earth's surface - the ground beneath our feet - constitutes the basis for life and natural resources, yet a general physical understanding of the ground is still lacking. In this critical time of climate change, cross-pollination of scientific approaches is urgently needed to better understand the behavior of our planet's surface. The major topics in current research in this area cross different disciplines, spanning geosciences, and various aspects of engineering, material sciences, physics, chemistry, and biology.
View Article and Find Full Text PDFBackground: A first febrile urinary tract infection (UTI) is a common condition in children, and pathways of management have evolved over time.
Objective: To determine the extent to which pediatricians and surgeons differ in their investigation and management of a first febrile UTI, and to evaluate the justifications for any divergence of approach.
Materials And Methods: A literature search was conducted for papers addressing investigation and/or management following a first febrile UTI in children published between 2011 and 2021.
Pediatr Nephrol
September 2023
Vesico-ureteric reflux (VUR) into transplanted kidneys in children and young people is a common occurrence, found in 19 to 60% of those who had an anti-reflux procedure and up to 79% in the absence of such a procedure. While VUR is unlikely to be of concern without evidence of symptomatic urinary tract infections, less certainty exists regarding outcomes when the VUR is associated with urinary tract infection (UTI) and transplant pyelonephritis. Issues explored will include additional risk factors that might predispose to UTI, any effect of pyelonephritis on acute and long-term kidney allograft function and practical strategies that may reduce the prevalence of infection.
View Article and Find Full Text PDFThe flow speed of the Greenland Ice Sheet changes dramatically in inland regions when surface meltwater drains to the bed. But ice-sheet discharge to the ocean is dominated by fast-flowing outlet glaciers, where the effect of increasing surface melt on annual discharge is unknown. Observations of a supraglacial lake drainage at Helheim Glacier, and a consequent velocity pulse propagating down-glacier, provide a natural experiment for assessing the impact of changes in injected meltwater, and allow us to interrogate the subglacial hydrological system.
View Article and Find Full Text PDFThe Greenland ice sheet has been one of the largest sources of sea-level rise since the early 2000s. However, basal melt has not been included explicitly in assessments of ice-sheet mass loss so far. Here, we present the first estimate of the total and regional basal melt produced by the ice sheet and the recent change in basal melt through time.
View Article and Find Full Text PDFPurpose Of Review: The aim of this review is to highlight the most recent developments in the understanding of kidney damage associated with vesico ureteral reflux. The severe damage, with major adverse long-term sequelae, was thought to be, for the most part, the result of pyelonephritis, predisposed to by vesico ureteral reflux.
Recent Findings: It is now recognized that there are two distinct forms of kidney damage (congenital and acquired), in association with reflux.
Vesico-ureteral reflux (VUR) has long been recognized as associated with urinary tract infections (UTIs), renal scarring, and chronic kidney disease (CKD). The concept of "reflux nephropathy" was born, whereby the VUR was considered the culprit, predisposing to recurrent UTIs and providing a conduit whereby the infection could ascend to the kidneys resulting in scarring and destruction. The more severe grades of reflux were thought to place the young child at particular risk of CKD.
View Article and Find Full Text PDFWe study the indentation of a rigid object into a layer of a cohesive or non-cohesive plastic material. Existing approaches to this problem using slip-line theory assume that the penetration depth is relatively small, employing perturbation theory about a flat surface. Here, we use two alternative approaches to account for large penetration depths, and for the consequent spreading and uplift of the surrounding material.
View Article and Find Full Text PDFWe demonstrate "bendotaxis," a novel mechanism for droplet self-transport at small scales. A combination of bending and capillarity in a thin channel causes a pressure gradient that, in turn, results in the spontaneous movement of a liquid droplet. Surprisingly, the direction of this motion is always the same, regardless of the wettability of the channel.
View Article and Find Full Text PDFExperiments are conducted to measure the resistance experienced by light cylinders rolling over flat beds of granular media. Sand and glass spheres are used for the beds. The trajectories of the rolling cylinders are determined through optical tracking, and velocity and acceleration data are inferred through fits to these trajectories.
View Article and Find Full Text PDFContext: Acute pyelonephritis may result in renal scarring. Recent prospective studies have shown a small benefit of antibiotic prophylaxis in preventing symptomatic and febrile urinary tract infections (UTIs), while being underpowered to detect any influence in prevention of renal damage.
Objectives: Review of the literature and a meta-analysis to evaluate the effect of antibiotic prophylaxis on UTI-related renal scarring.
Nephrology (Carlton)
February 2017
The understanding of the role of complement dysregulation in atypical haemolytic uraemic syndrome (aHUS) has led to major changes in therapeutic approaches and outcomes. Eculizumab is a humanized anti-C5 monoclonal antibody that inhibits the terminal complement pathway and has revolutionized the treatment and prognosis of aHUS. However, published reports to date have had relatively short-term follow-up.
View Article and Find Full Text PDFWe consider the problem of capillary imbibition into an axisymmetric tube for which the tube radius decreases in the direction of increasing imbibition. For tubes with constant radius, imbibition is described by Washburn's law (referred to here as the BCLW law to recognize the contributions of Bell, Cameron, and Lucas that predate Washburn). We show that imbibition into tubes with a power-law relationship between the radius and axial position generally occurs more quickly than imbibition into a constant-radius tube.
View Article and Find Full Text PDFObjective: To evaluate the yield, economic, and radiation costs of 5 diagnostic algorithms compared with a protocol where all tests are performed (ultrasonography scan, cystography, and late technetium(99)dimercaptosuccinic acid scan) in children after the first febrile urinary tract infections.
Methods: A total of 304 children, 2 to 36 months of age, who completed the diagnostic follow-up (ultrasonography, cystourethrography, and acute and late technetium(99)dimercaptosuccinic acid scans) of a randomized controlled trial (Italian Renal Infection Study 1) were eligible. The guidelines applied to this cohort in a retrospective simulation were: Melbourne Royal Children's Hospital, National Institute of Clinical Excellence (NICE), top down approach, American Academy of Pediatrics (AAP), and Italian Society of Pediatric Nephrology.
Studies undertaken in recent years have improved our understanding regarding the consequences and management of febrile urinary tract infections (UTIs), which are amongst the most common serious bacterial infections in childhood, with renal scarring a frequent outcome. In the past pyelonephritic scarring of the kidney, often associated with vesico-ureteral reflux (reflux nephropathy) was considered a frequent cause of chronic renal insufficiency in children. Increasing recognition as a consequence of improved antenatal ultrasound, that the majority of these children had congenital renal hypo-dysplasia, has resulted in a number of studies examining treatment strategies and outcomes following UTI.
View Article and Find Full Text PDFArch Pediatr Adolesc Med
November 2011