Groundwater dependent ecosystems (GDEs) are vulnerable to groundwater regime changes. However, their protection is often hampered by challenges in their identification. Within is presented a remote ...sensing-based GDE potential mapping approach based on the persistency of relevant vegetation parameters during prolonged dry periods as an indicator of potential 'consistency' of water supply (e.g. groundwater). The study uses a novel approach to characterising persistency for selected vegetation parameters based on a normalised difference measure and an adaptation of the coefficient of variation statistic. Aggregation of parameters was facilitated through the analytic hierarchy process providing a structured weighting approach to minimise parameter bias. The approach is demonstrated in the semi-arid Flinders Ranges of South Australia where new groundwater resources are being sought to support local domestic and industry needs. Variations in GDE potential were mapped to better target areas where exploration of groundwater should be avoided. Mapping results indicated a high-level of agreement of 77% with an independent springs dataset, along with an 87% agreement with areas coinciding with known phreatophyte species and depths to groundwater. The index-based mapping approach has potential applicability across landscapes, as it normalises for variations in vegetation cover, minimises technical overheads, and employs continental-wide remote sensing data-products.
The renin-angiotensin system (RAS) is fundamental to COVID-19 pathobiology, due to the interaction between the SARS-CoV-2 virus and the angiotensin-converting enzyme 2 (ACE2) coreceptor for cellular ...entry. The prevailing hypothesis is that SARS-CoV-2-ACE2 interactions lead to an imbalance of the RAS, favoring proinflammatory angiotensin II (ANG II)-related signaling at the expense of the anti-inflammatory ANG-(1-7)-mediated alternative pathway. Indeed, multiple clinical trials targeting this pathway in COVID-19 are underway. Therefore, precise measurement of circulating RAS components is critical to understand the interplay of the RAS on COVID-19 outcomes. Multiple challenges exist in measuring the RAS in COVID-19, including improper patient controls, ex vivo degradation and low concentrations of angiotensins, and unvalidated laboratory assays. Here, we conducted a prospective pilot study to enroll 33 patients with moderate and severe COVID-19 and physiologically matched COVID-19-negative controls to quantify the circulating RAS. Our enrollment strategy led to physiological matching of COVID-19-negative and COVID-19-positive moderate hypoxic respiratory failure cohorts, in contrast to the severe COVID-19 cohort, which had increased severity of illness, prolonged intensive care unit (ICU) stay, and increased mortality. Circulating ANG II and ANG-(1-7) levels were measured in the low picomolar (pM) range. We found no significant differences in circulating RAS peptides or peptidases between these three cohorts. The combined moderate and severe COVID-19-positive cohorts demonstrated a mild reduction in ACE activity compared with COVID-19-negative controls (2.2 ± 0.9 × 10
vs. 2.9 ± 0.8 × 10
RFU/mL,
= 0.03). These methods may be useful in designing larger studies to physiologically match patients and quantify the RAS in COVID-19 RAS augmenting clinical trials.
Regression to the mean (RTM) is a statistical phenomenon where initial measurements of a variable in a nonrandom sample at the extreme ends of a distribution tend to be closer to the mean upon a ...second measurement. Unfortunately, failing to account for the effects of RTM can lead to incorrect conclusions on the observed mean difference between the 2 repeated measurements in a nonrandom sample that is preferentially selected for deviating from the population mean of the measured variable in a particular direction. Study designs that are susceptible to misattributing RTM as intervention effects have been prevalent in nutrition and obesity research. This field often conducts secondary analyses of existing intervention data or evaluates intervention effects in those most at risk (i.e., those with observations at the extreme ends of a distribution).
To provide best practices to avoid unsubstantiated conclusions as a result of ignoring RTM in nutrition and obesity research.
We outlined best practices for identifying whether RTM is likely to be leading to biased inferences, using a flowchart that is available as a web-based app at https://dustyturner.shinyapps.io/DecisionTreeMeanRegression/. We also provided multiple methods to quantify the degree of RTM.
Investigators can adjust analyses to include the RTM effect, thereby plausibly removing its biasing influence on estimating the true intervention effect.
The identification of RTM and implementation of proper statistical practices will help advance the field by improving scientific rigor and the accuracy of conclusions. This trial was registered at clinicaltrials.gov as NCT00427193.
Earlier detection of microalbuminuria in diabetic patients using a new urinary albumin assay.
Microalbuminuria is regarded as the most important predictor of high risk for the development of diabetic ...nephropathy. Early detection may allow treatment to prevent progression to persistent albuminuria and renal failure. Recent studies have shown that conventional immunoassays underestimate urinary albumin concentration, as albumin in urine may exist in two forms, immuno-reactive and immuno-unreactive. The present study examines the differential lead-time for the development of microalbuminuria as measured by both conventional radioimmunoassay (RIA; measures immuno-reactive) and high-performance liquid chromatography (HPLC; measures total albumin = immuno-reactive plus immuno-unreactive) analysis in both type 1 and type 2 diabetic patients.
Analysis was performed on 511 stored urine samples collected over the last 13years from type 1 diabetic patients who either progressed from normo- to microalbuminuria (progressors, N = 17), or who remained normoalbuminuric (nonprogressors, N = 25) as defined by RIA, and on 634 urine samples collected from patients with type 2 diabetes defined as either progressors (N = 24) or nonprogressors (N = 25).
For type 1 progressors, the mean lead-time for the HPLC assay versus the RIA was 3.9years, with a 95% CI of 2.1 to 5.6years. For type 2 progressors, the mean lead-time was 2.4years with a 95% CI of 1.2 to 3.5years. There was no significant difference between the lead-time analysis between type 1 and type 2 diabetic patients.
These results demonstrate that measurement of total albumin may allow earlier detection of microalbuminuria associated with diabetic nephropathy.
River management continues to challenge riparian systems worldwide, with climate change impacts and anthropogenic extractions escalating. The Murray–Darling basin (MDB) in Australia is critical to ...agricultural production and habitat provision to maintain biodiversity. Concern for the condition of native trees and biota in the MDB has led to substantial research investment to increase ecosystem function understanding and improve floodplain and wetland management. This field study offers new insights into tree nutrition and physiology as interpreted against the plant-soil-environment dynamics of recent flooding. Black Box (
Eucalyptus largiflorens
(Myrtaceae) is the only key native riverine MDB tree restricted to that region; and appears stressed at the far reaches of certain significant floodplain ecosystems. Here, nutritional and ecophysiological comparisons were made between Black Box trees that had just been inundated, and those nearby that had not. Leaf stomatal conductance, transpiration, total soil aluminium (Al) concentration, soil pH, and soil conductivity were different between inundated and dry sites. Soil moisture increased due to inundation, thus reducing tree water stress across the three study locations. Changes in leaf chemistry were not detected at the very early stages of flooding examined in this study. An increase in soil acidity due to inundation may also enhance bioavailability of nutrients to trees. New insight into immediate plant benefits gained from this study suggests further investigation is warranted to elucidate the influence of flood and drought on nutrient balance and how future wetland management can benefit from a more holistic understanding of plant-soil-environment dynamics.
Engagement in one type of health behavior change may exert a “spillover” effect resulting in other behavior changes. Few studies have examined dietary intake following prolonged training, and none ...have evaluated spontaneous dietary changes beyond alterations in energy or macronutrient intake following initiation of strength/resistance training (RT). The purpose of this observational investigation was to determine if spontaneous dietary intake modifications occur in response to initiation of an RT program, among older adults. Previously sedentary adults with prediabetes (n=134, age=59±1years) were enrolled in a supervised 12-week RT program. Participants were not given dietary advice or encouraged to change eating behaviors. Three non-consecutive 24-hour dietary recalls were collected at baseline and after 12weeks of RT. Reductions in intake of energy (1914±40kcal vs. 1834±427kcal, p=0.010), carbohydrate (211.6±4.9g vs. 201.7±5.2g, p=0.015), total sugar (87.4±2.7g vs. 81.5±3.1g, p=0.030), glycemic load (113.4±3.0 vs. 108.1±3.2, p=0.031), fruits and vegetables (4.6±0.2 servings vs. 4.1±0.2 servings, p=0.018), and sweets and desserts (1.1±0.07 servings vs. 0.89±0.07 servings, p=0.023) were detected over time. No changes in other dietary intake variables were observed. Mode of exercise and disease state may be important factors in determining whether dietary modifications occur with exercise initiation, among previously sedentary adults. Successful initiation of RT may represent an opportunity for health care professionals to promote beneficial changes in dietary habits, among older adults with prediabetes.
•We assessed dietary changes among adults with prediabetes, after strength training.•A resistance training program was initiated; nutrition counseling was not provided.•Participants decreased energy, carbohydrate and total sugar intake.•Reduced consumption of fruits/vegetables and sweets/desserts was also noted.
Prescription drug expenditures represent a significant component of health care costs in Canada, with estimates of $28.8 billion spent in 2014. Identifying the major cost drivers and the effect they ...have on prescription drug expenditures allows policy makers and researchers to interpret current cost pressures and anticipate future expenditure levels.
To identify the major drivers of prescription drug costs and to develop a methodology to disaggregate the impact of each of the individual drivers.
The methodology proposed in this study uses the Laspeyres approach for cost decomposition. This approach isolates the effect of the change in a specific factor (e.g., price) by holding the other factor(s) (e.g., quantity) constant at the base-period value. The Laspeyres approach is expanded to a multi-factorial framework to isolate and quantify several factors that drive prescription drug cost. Three broad categories of effects are considered: volume, price and drug-mix effects. For each category, important sub-effects are quantified.
This study presents a new and comprehensive methodology for decomposing the change in prescription drug costs over time including step-by-step demonstrations of how the formulas were derived.
This methodology has practical applications for health policy decision makers and can aid researchers in conducting cost driver analyses. The methodology can be adjusted depending on the purpose and analytical depth of the research and data availability.
High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for ...only a few non-microbial species
. To address this issue, the international Genome 10K (G10K) consortium
has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences.
Mixed amphetamine salts extended release (MAS XR; Adderall XR®) and atomoxetine (Strattera®) were compared in children 6 to 12 years old with attention deficit/hyperactivity disorder (ADHD) combined ...or hyperactive/impulsive type in a randomized, double-blind, multicenter, parallel-group, forced-dose-escalation laboratory school study. Primary efficacy measure was the SKAMP (Swanson, Kotkin, Agler, M-Flynn, and Pelham) behavioral rating scale. Changes in mean SKAMP deportment scores from baseline were significantly greater for MAS XR (n = 102) than for atomoxetine (n = 101) overall (-0.56 and -0.13, respectively; p < .0001) and at each week (p < .001). Adverse events were similar for both treatment groups. The extended time course of action and greater therapeutic efficacy of MAS XR suggests that it is more effective than atomoxetine in children with ADHD.
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