Significant Mismatch Research Articles

Metrics to evaluate implementation scientists in the USA: what matters most?

BackgroundImplementation science has grown rapidly as a discipline over the past two decades. An examination of how publication patterns and other scholarly activities of implementation scientists are weighted in the tenure and promotion process is needed given the unique and applied focus of the field.MethodsWe surveyed implementation scientists (mostly from the USA) to understand their perspectives on the following matters: (1) factors weighted in tenure and promotion for implementation scientists, (2) how important these factors are for success as an implementation scientist, (3) how impact is defined for implementation scientists, (4) top journals in implementation science, and (5) how these journals are perceived with regard to their prestige. We calculated univariate descriptive statistics for all quantitative data, and we used Wilcoxon signed-rank tests to compare the participants’ ratings of various factors. We analyzed open-ended qualitative responses using content analysis.ResultsOne hundred thirty-two implementation scientists completed the survey (response rate = 28.9%). Four factors were rated as more important for tenure and promotion decisions: number of publications, quality of publication outlets, success in obtaining external funding, and record of excellence in teaching. Six factors were rated as more important for overall success as an implementation scientist: presentations at professional meetings, involvement in professional service, impact of the implementation scientist’s scholarship on the local community and/or state, impact of the implementation scientist’s scholarship on the research community, the number and quality of the implementation scientist’s community partnerships, and the implementation scientist’s ability to disseminate their work to non-research audiences. Participants most frequently defined and described impact as changing practice and/or policy. This expert cohort identified Implementation Science as the top journal in the field.ConclusionsOverall, there was a significant mismatch between the factors experts identified as being important to academic success (e.g., tenure and promotion) and the factors needed to be a successful implementation scientist. Findings have important implications for capacity building, although they are largely reflective of the promotion and tenure process in the USA.

Perpetuating Disparity: Failure of the Kidney Transplant System to Provide the Most Kidney Transplants to Communities With the Greatest Need.

The burden of end-stage kidney disease (ESKD) and kidney transplant rates vary significantly across the United States. This study aims to examine the mismatch between ESKD burden and kidney transplant rates from a perspective of spatial epidemiology. US Renal Data System data from 2015 to 2017 on incident ESKD and kidney transplants per 1000 incident ESKD cases was analyzed. Clustering of ESKD burden and kidney transplant rates at the county level was determined using local Moran's I and correlated to county health scores. Higher percentile county health scores indicated worse overall community health. Significant clusters of high-ESKD burden tended to coincide with clusters of low kidney transplant rates, and vice versa. The most common cluster type had high incident ESKD with low transplant rates (377 counties). Counties in these clusters had the lowest overall mean transplant rate (61.1), highest overall mean ESKD incidence (61.3), and highest mean county health scores percentile (80.9%, P <0.001 vs all other cluster types). By comparison, counties in clusters with low ESKD incidence and high transplant rates (n=359) had the highest mean transplant rate (110.6), the lowest mean ESKD incidence (28.9), and the lowest county health scores (20.2%). All comparisons to high-ESKD/low-transplant clusters were significant at P value <0.001. There was a significant mismatch between kidney transplant rates and ESKD burden, where areas with the greatest need had the lowest transplant rates. This pattern exacerbates pre-existing disparities, as disadvantaged high-ESKD regions already suffer from worse access to care and overall community health, as evidenced by the highest county health scores in the study.

Improving the glass forming ability and plasticity of ZrCuNiAlTi metallic glass by substituting Zr with Sc

The present study reports the effect of substituting Zr with Sc on the glass forming ability (GFA) and mechanical properties of ZrCuNiAlTi bulk metallic glass (BMG). Results showed that Zr 57- x Cu 20 Ni 8 Al 10 Ti 5 Sc x ( x = 0, 1, 2, 3, 4 at%) BMGs had the best GFA at x = 2, and the critical size was 10 mm, which correlated well with the GFA indicator ( T rg and γ ). The large atomic radius of Sc and small Gibbs free energy difference between the supercooled liquid and crystalline solid (Δ G l-c ) caused significant atomic size mismatch and inhibited crystallization during cooling, ultimately improving GFA. Compression test results indicated that the plasticity of the Zr 55 Cu 20 Ni 8 Al 10 Ti 5 Sc 2 BMG increased fivefold (9.1%) relative to that of the Sc-free case, whereas fracture stress was successfully retained at a value of 1815 MPa. The high plastic strain of Zr 55 Cu 20 Ni 8 Al 10 Ti 5 Sc 2 BMG can be attributed to the localized nanocrystallization phenomenon under uniaxial compression and to the high relaxed excess free volume (REFV) in ZrCuNiAlTiSc BMGs. The high REFV prevented the expansion of shear bands, generated secondary shear bands, and finally increased plasticity. • GFA and plasticity are both enhanced by substituting with Sc in ZrCuNiAlTi BMGs. • The smaller ΔGl-c of Sc2 compared with Sc-free BMG results in its high GFA. • Nanocrystalline phenomenon is the main reason for the high plasticity of Sc2 BMG. • The high plasticity of Sc2 alloy is also attributed to its higher REFV than others.

Humidity-Responsive Actuators Based on Firm Heterojunction of Glycerol-Cross-linked Polyvinyl Alcohol and Porous Polyvinylidene Fluoride as Smart Gates for Anti-condensation

In this study, novel humidity-responsive actuators are developed based on firm heterojunction of glycerol-cross-linked polyvinyl alcohol (Gly@PVA) and porous polyvinylidene fluoride (PVDF) via a facile strategy for achieving humidity control and anti-condensation functions. The firm heterojunction of Gly@PVA and PVDF with extremely high interfacial toughness is achieved by simply bonding the Gly@PVA layer and plasma-treated porous PVDF layer via a coating–freezing–drying process. The addition of glycerol in polyvinyl alcohol (PVA) increases the moisture adsorption capacity, resulting in a significant mismatch between the humidity-responsive properties of the humidity-active Gly@PVA and inert PVDF layers. With the mass ratio of glycerol to PVA as 17.5%, the Gly@PVA/PVDF bilayer actuators exhibit humidity-responsive bending behaviors with a bending angle change as large as 216.4° when the environmental relative humidity (RH) changes from 25 to 95%. Based on the humidity-responsive bending property, Gly@PVA/PVDF bilayer films are designed and patterned as humidity-responsive smart gates. By equipping sealed chambers and food crispers with such smart gates, which can rapidly open and release excessive moisture out in time when the inside RH exceeds a critical value, excellent performances of humidity control, anti-condensation, and food preservation are effectively achieved. The proposed strategy is highly promising for developing efficient humidity-responsive actuators for various applications.

Shale’s Pore Structure and Sorption-Diffusion Characteristics: Effect of Analyzing Methods and Particle Size

The delineation of pore size and surface area distribution and methane sorption-diffusion capacity in gas shale reservoirs is crucial for the estimation of storage capacity, anticipating flow characteristics, and field development. A systematic approach and guidelines are needed for the analysis of the pore size and surface area distribution of shale formations. The effect of shale sample size on the gas sorption and diffusion properties is not well understood either. The low-pressure nitrogen adsorption technique is a prevalent method for pore characterization of nanoporous shale formations. Although researchers adopted some corrections to the classical method for the analysis of pore size and surface area distribution, there is a significant mismatch between different approaches in depicting fine mesopore size and surface area (2–10 nm). In this study, the classical methods and density functional theory are employed to comparatively analyze the pore characteristics of some shale and clay samples for their applicability, efficacy, and consistency issues. Furthermore, the effect of shale particle size on the methane sorption capacity and diffusion is being investigated. It seems that confinement stress has less of a considerable effect on methane sorption (6% decrease). However, crushing shale rocks into smaller particles can significantly overestimate the methane adsorption capacity. The methane diffusion coefficient also increases with increasing the shale particle size by more than an order of magnitude.

Development of a novel predictive model for a successful stone removal after flexible ureteroscopic lithotripsy based on ipsilateral renal function: a single-centre, retrospective cohort study in China.

ObjectivesThe aims of this study were to investigate the effect of preoperative ipsilateral renal function on the success of kidney stone removal with flexible ureteroscopic lithotripsy and to develop a predictive model based on the results.DesignRetrospective cohort study.SettingData from the 2001–2012 period were collected from the electronic records of West China Hospital, Sichuan University.Participants576 patients who underwent flexible ureteroscopic lithotripsy were included in the study.Primary outcomeStone-free rate (SFR) after the procedures.ResultsIn patients with suspected impaired kidney function, the overall SFR was 70.1%. Stone volume (OR 1.46; 95% CI 1.18 to 1.80), lower calyx stones (OR 1.80; 95% CI 1.22 to 2.65), age (OR 1.02; 95% CI 1.00 to 1.04), body mass index (OR 1.10; 95% CI 1.04 to 1.17) and estimated glomerular filtration rate of the affected kidney (OR 0.95; 95% CI 0.94 to 0.97) were identified as independent predictors of SFR. Lasso regression selected the same five predictors as those identified by univariate and multivariate logistic regression analyses, thus verifying our model. The mean area under the curve, based on 1000 iterations and 10-fold validation, was 0.715 (95% CI 0.714 to 0.716). The Hodges-Lehmann test and calibration curve analysis revealed no significant mismatch between the prediction model and the retrospective cohort.ConclusionIpsilateral renal function may be a novel independent risk factor for kidney stone removal with flexible ureteroscopic lithotripsy. A novel nomogram for predicting SFR that uses stone volume, lower calyx stones, age, body mass index and estimated glomerular filtration rate was developed, but remains to be externally validated.

Simulation of Maralal Water Flow Distribution Network using EPANET Model in Samburu County, Kenya

Majority of people in developing countries do not have access to clean and potable water due to inadequate supply and distribution system challenges. While the rationale of water distribution systems is to deliver to each consumer safe drinking water that is adequate in quality and quantity at an acceptable delivery pressure, this has been a major drawback for many distribution networks. In addition, the design spans of many urban and peri-urban water distribution networks managed by the Water Service Providers (WSPs) are being exceeded without augmentation. Maralal water distribution network is one of such distribution systems with poor system performance that has been the main contributor of high Non-Revenue Water (NRW). This coupled with significant mismatch between water supply and water demand makes Maralal Water and Sanitation Company to resort to hedging/intermittent flow leading to water rationing. One of the ways of predicting the flow dynamics within the distribution system is the use of hydraulic simulation models. This study therefore applied the Environmental Protection Agency Network (EPANET) simulation model to predict the dynamic state of the hydraulics and water quality behaviour for Maralal water distribution system operating over an extended period of time. The general objective was to simulate water flow for Maralal water distribution system using the EPANET model for efficient planning, operation and maintenance protocol for the system. The study focused on the steady state (static), extended period (dynamic), and water quality analyses. The model calibration results from four statistical criteria; Nash-Sutcliffe model efficiency coefficient (E), Sum of Squares Error (SSE), Percentage Bias (PB) and Root Mean Square Error (RMSS) of 0.99, 0.01, 0.05 and 0.03 respectively show that the model performed within acceptable range of the selected statistical criteria. The findings of this study were: The roughness coefficients for a water distribution network that contribute to erratic pressure-dependent flows can be determined at any time using the regression analysis of the measured head loss and flow rate, EPANET model can predict the steady and dynamic hydraulic parameters for the current and future water distribution systems and Chlorine decay with respect to pipe diameter impacts on hydraulic performance and quality of water in a distribution network. The results from this study would assist water service providers and managers to make informed decisions in relation to water distribution system planning, operation and maintenance to achieve the desired current and future water demands.

Systemic Risk Factors for Adult Spinal Deformity (ASD): A Retrospective Analysis of 48 Patients.

Introduction: Adult spinal deformity (ASD) results in significant patient morbidity and burden to quality of life. The degree to which systemic risk factors and comorbidities that contribute to ASD affect specific spinopelvic parameters is not well-documented. We determine the extent to which preoperative risk factors may contribute to spinopelvic parameters associated with ASD.Methods: Retrospective single-center study of 48 patients with ASD. Analysis of variance (ANOVA) linear regression analysis was performed to evaluate correlation between systemic comorbidities (obesity, arterial hypertension (HTN), hyperlipidemia (HLD), cardiomyopathy, diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), and asthma) and the following radiographic parameters: pelvic incidence (PI), lumbar lordosis (LL), C7 sagittal vertical axis (C7SVA), and the T10-L2 sagittal cobb angle.Results: A total of 48 patients were included with mean C7SVA of 79.6 mm (SD: 63, range: 43-254), mean LL of 32.9° (SD: 15.9, range: -14 to 78), T10-L2 sagittal cobb angle of 3° (SD: 12.7, range: -24 to 30), and PI was 49° (SD: 10.7, range: 21 to 77). Only DM correlated with sagittal imbalance with high C7SVA and PI-LL mismatch. The beta coefficient for DM and preoperative C7SVA was 0.49, t=3.16, p=0.003, preoperative PI-LL mismatch standardized beta coefficient was -0.4, t=-2.38, p=0.022, and preoperative T10-L2 sagittal cobb standard beta coefficient was -0.07, t=-0.46, p=0.645. No significant correlations were found for asthma, COPD, HTN, HLD, or cardiomyopathy.Conclusions: Diagnosis of DM was found to correlate with pathologic C7SVA and significant PI-LL mismatch associated with ASD. HTN, HLD, cardiomyopathy, obesity, and pulmonary disease did not correlate with radiographic findings of sagittal imbalance.

Graphene coated 3C-SiC with improved irradiation resistance and enhanced heat conduction property after collision cascade

Graphene/SiC nanocomposites are promising materials with excellent irradiation resistance. In this study, the structure of 3C-SiC coated with graphene layers is proposed to improve SiC's irradiation resistance. The atomistic mechanisms behind the irradiation resistance and irradiation's effect on the thermal conductance of the composite are investigated through molecular dynamics simulations. Results show that the graphene layers effectively enhanced the irradiation resistance of SiC in the composite with increased threshold displacement energy when irradiated with a carbon primary knock-on atom (PKA). Influence factors, i.e., graphene layer number, incident angle of the PKA, and temperature, of irradiation resistance are also studied by collision cascade simulations. In addition, the heat conduction of the composite is enhanced after the irradiation with the 1.5 keV carbon PKA. The resistance dominates the thermal transport at the graphene layers near the interface instead of the interface. The largest temperature drop occurs between the interface and the penultimate graphene layer, consistent with the significant mismatch of their vibrational density of states. After irradiation with the 1.5 keV carbon PKA, the thermal conductance of the graphene/SiC composites increases, and the interface thermal resistance decreases due to the formed bonds between the graphene layers. Overall, this work provides a fundamental understanding of the irradiation resistance and the thermal properties of the graphene/SiC composite.

Calibrated Frequency-Division Distorted Born Iterative Tomography for Real-Life Head Imaging.

The clinical use of microwave tomography (MT) requires addressing the significant mismatch between simulated environment, which is used in the forward solver, and real-life system. To alleviate this mismatch, a calibrated tomography, which uses two homogeneous calibration phantoms and a modified distorted Born iterative method (DBIM), is presented. The two phantoms are used to derive a linear model that matches the forward solver to real-life measurements. Moreover, experimental observations indicate that signal quality at different frequencies varies between different antennas due to inevitably inconsistent manufacturing tolerance and variances in radio-frequency chains. An optimum frequency, at which the simulated and measured signals of the antenna present maximum similarity when irradiating the calibrated phantoms, is thus calculated for each antenna. A frequency-division DBIM (FD-DBIM), in which different antennas in the array transmit their corresponding optimum frequencies, is subsequently developed. A clinical brain scanner is then used to assess performance of the algorithm in lab and healthy volunteers' tests. The linear calibration model is first used to calibrate the measured data. After that FD-DBIM is used to solve the problem and map the dielectric properties of the imaged domain. The simulated and experimental results confirm validity of the presented approach and its superiority to other tomographic method.

Low temperature co-sintering simulation and properties analysis of 3D printed SiO2[sbnd]B2O3 nanoparticles based on molecular dynamics simulation

3D printing (3DP) permits the integrated precise and rapid molding of low-temperature co-fired ceramics (LTCC). However, the relationship between microstructure and characteristics during sintering remains a challenge. The multi-nanoparticle sintering behavior of the ultra-low dielectric constant LTCC combination SiO2B2O3 is reproduced by using molecular dynamics (MD) simulation. A trustworthy equivalent model to extract the effective dielectric constant (εeff) of multiphase structures is developed based on fractal verification with the experimental picture. The simulated 3DP-formed 8 nm sample leads to an ultra-low dielectric constant of even lower than 3 due to the high through-hole ratio. Uniaxial tension testing of the sintered structures demonstrated the contribution of pre-pressing on the mechanical properties. The ultimate strength of the 6 nm sample formed by 3DP is approximately 1.71 Gpa, which is an increase of over 44% compared to the 8 nm sample (1.18 Gpa), but still below the yield point of the pre-pressed 6 nm sample (3.28 Gpa). Further combined with strain distribution revealed that the B2O3 aid particles, as the primary stress-bearing phase, have a significant impact on the mechanical properties. In addition, the thermal conductivity (TC) and linear thermal expansion coefficient (TEC) are evaluated to assess thermal stability. Detailed modeling of the SiO2/B2O3 interface exhibit a significant mismatch between the phonon spectra of the SiO2 and B2O3 layers in the vibrational range of 27–40 THz, which leads to differences in thermal conductivity between the 3DP formed and pre-pressed samples.

Electrochemical modeling and parameterization towards control-oriented management of lithium-ion batteries

Battery management systems based on electrochemical models could achieve more accurate state estimations and efficient battery controls with access to cell unmeasurable physical variables. As battery electrochemical models are governed by first-principle partial differential equation sets, model complexity and multiple parameter determination are bottlenecks for their wider applications. This paper gives a systematical review of recent advancements in electrochemical model development and parameterization. Specifically, classic pseudo-two-dimensional model and related model order reduction methodologies are first summarized and analyzed. Given that the homogenization hypothesis of the pseudo-two-dimensional model could lead to significant model mismatch under some operational conditions, enhanced models considering cell internal inhomogeneity with multi-particles, multi-scales, aging and thermal dynamics are examined. To facilitate model portability, parameter identification techniques of these models are classified, and solutions for optimizing the parameterization procedure are explored. Finally, current research gaps in the literature and remaining challenges are discussed and highlighted with some suggestions. This review will therefore inform the engineers of battery management and control engineering, whilst boosting the research, design and operation of control-oriented electrochemical models for smarter battery management at different readiness levels.

Ignoring variation in wood density drives substantial bias in biomass estimates across spatial scales

Rapid development of remote sensing and Light Detection and Ranging (LiDAR) technology has refined estimates of tree architecture and extrapolation of biomass across large spatial scales. Yet, current biomass maps show significant discrepancies and mismatch to independent ground data. A potential obstacle to accurate biomass estimation is the loss of information on wood density, which can vary at local and regional scales, in the extrapolation process. Here we investigate if variation in wood specific gravity (WSG) substantially impacts the distribution of above-ground biomass (AGB) across a range of scales from local plots to large regions. We collected wood cores and measured tree volume in 341 forest sites across large altitudinal and climatic gradients in Colombia. At all spatial scales, variation in WSG was substantial compared to variation in volume. Imputing study-wide average values of WSG induced regional biases in AGB estimates of almost 30%, consequently undervaluing the difference between forest areas of low and high average wood density. Further, neither stem size nor climate usefully predicted WSG when accounting for spatial dependencies among our sampling plots. These results suggest that remote sensing- and LiDAR-based projections to biomass estimates can be considerably improved by explicitly accounting for spatial variation in WSG, necessitating further research on the spatial distribution of WSG and potential environmental predictors to advance efficient and accurate large-scale mapping of biomass.

The influence of threading dislocations propagating through an AlGaN UVC LED

During the epitaxy of AlGaN on sapphire for deep UV emitters, significant lattice mismatch leads to highly strained heterojunctions and the formation of threading dislocations. Combining cathodoluminescence, electron beam induced current and x-ray microanalysis reveal that dislocations with a screw component permeate through a state-of-the-art UVC LED heterostructure into the active region and perturb their local environment in each layer as growth progresses. In addition to acting as non-radiative recombination centers, these dislocations encourage high point defect densities and three-dimensional growth within their vicinity. We find that these point defects can add parasitic recombination pathways and compensate intentional dopants.

Investigation of the effect of the envelope on building thermal storage performance under model predictive control by dynamic pricing

Dynamic pricing is designed for the load shaping to help match the amount of the energy demand to the energy supply capacity. Since the buildings’ characteristics influence the performance of the energy shifting, renovation of the building towards a higher energy flexibility is worth investigating. This study evaluated the effect of the envelope on building thermal storage performance. A model predictive control (MPC) was developed to achieve a multi-objective control i.e., indoor comfort temperature and minimise the total energy cost. MPC automatically triggered the energy storage during the low price periods and used the stored energy during the high price periods. The results confirmed the ability of MPC on peak demand reduction up to 45% electricity cost. Besides, the results also demonstrated the ability of heavyweight thermal mass in terms of reducing energy consumption and shifting a greater high price energy to the low price times. Therefore, adding insulation layers into the lightweight thermal mass is highly recommended, especially for the places experiencing the significant mismatch between the demand and supply during daily peaks or the areas scheduling a large amount of intermittent renewable energy source in the energy production.

High extinction ratio and broadband polarization beam splitter based on bricked subwavelength gratings on SOI platform

A compact asymmetrical directional coupler (ADC) based on coupling between a conventional subwavelength grating (SWG) and a bricked subwavelength grating (BSWG) is proposed to realize broadband polarization beam splitter (PBS) with high extinction ratio (ER) on silicon-on-insulator (SOI) platform. Apart from conventional SWG structural parameters (duty cycle and period), the BSWG is utilized to provide a new design space to control TE and TM modal effective index for accurate phase match. Accordingly, as to the TM mode, it is possible to satisfy phase-matching condition and then can be coupled more efficiently with higher ER by introducing the BSWG. Meanwhile, there is a significant phase mismatch for the TE mode. In this way, the proposed PBS that separates TE and TM mode to the through and cross ports can be realized. Simulation results show that the proposed PBS with a compact coupling length of 8.4 μm can achieve a high ER of 35.06 dB and an insertion loss of 0.25 dB for the TM mode at 1.55 μm, while the ER is 18.92 dB and insertion loss is 0.01 dB for the TE mode. Moreover, the operating bandwidth is up to 300 nm (1400∼1700 nm) for the TE mode and 155 nm (1487∼1642 nm) for the TM mode when the ER is >15 dB.

High Power Mid-Infrared Quantum Cascade Lasers Grown on GaAs

The motivation behind this work is to show that InP-based intersubband lasers with high power can be realized on substrates with significant lattice mismatch. This is a primary concern for the integration of mid-infrared active optoelectronic devices on low-cost photonic platforms, such as Si. As evidence, an InP-based mid-infrared quantum cascade laser structure was grown on a GaAs substrate, which has a large (4%) lattice mismatch with respect to InP. Prior to laser core growth, a metamorphic buffer layer of InP was grown directly on a GaAs substrate to adjust the lattice constant. Wafer characterization data are given to establish general material characteristics. A simple fabrication procedure leads to lasers with high peak power (&gt;14 W) at room temperature. These results are extremely promising for direct quantum cascade laser growth on Si substrates.

Van der Waals growth of PbSe thin films on graphene and Bi2Se3

One of the major obstacles for integration of PbSe with Si-based electronics is the significant lattice mismatch between PbSe and Si. The rigid limitation on lattice-matching could be effectively loosened via the van der Waals growth strategy, in which as-grown film layer and underlying substrate are held together through the weak van der Waals interaction rather than the strong chemical bonds. Benefiting from the absence of dangling-bond at their surface, graphene and layered Bi2Se3 are two potential van der Waals materials for the relaxation of lattice mismatch between PbSe and Si. In this work, PbSe thin films were grown on surface of graphene and Bi2Se3 with the molecular beam epitaxy. A potential solution for the relaxation on lattice mismatch between PbSe and Si is thus explored.

Groundwater age persistence in topography-driven groundwater flow over paleohydrogeologic time scales

AbstractThe Pleistocene-Holocene climate transition resulted in a dramatic reduction in groundwater recharge in many aquifers in arid and semiarid regions throughout the world. This study conducted numerical experiments to compare the evolution of groundwater hydraulics and age patterns in arid and semiarid aquifers in response to transient conditions associated with recharge decline from the Pleistocene to the Holocene. Our results show that after a rapid reduction in recharge, the amplitude of water-table undulations and regional groundwater slope both reduced. This resulted in a general, and relatively rapid, contraction of local flow systems and an increase in the extent of intermediate and regional systems. The previous hierarchy of local, intermediate, and regional flow systems was completely replaced by largely horizontal and regional flow patterns after ~10,000 yr. However, in stark contrast, we observed that the original Pleistocene age patterns have remained almost unchanged throughout the 10,000 yr Holocene period. Thus, groundwater age is more likely to be indicative of past rather than current flow systems. Consequently, due to this age persistence, the use of modern groundwater age data to calibrate models or compute recharge with methods that do not account for this potentially significant spatial and temporal mismatch between age and hydraulics will be misleading and erroneous. This has significant implications for hydrogeologic analyses. The findings of this study may also apply to areas that have undergone dramatic changes in land cover or land use that strongly influence transient groundwater recharge processes.

Drug Testing for Chronic Kidney Disease and Diabetes in Animals versus Humans: A Comparative Analysis of Study Designs and Reporting Qualities

Introduction: Diabetes is a highly prevalent accelerator or even cause of chronic kidney disease imposing a large unmet medical need at the global scale. Massive research activities continue to be in search of a cure but the yield of the classical bench-to-bedside research approach has been low. We speculated that a significant mismatch in design and quality of animal and clinical studies in this domain is a hurdle for translation. Methods: We performed a meta-analysis of matched pairs of animal and human studies that tested the efficacy of distinct drug interventions for diabetic kidney disease (DKD). We reviewed study designs and reporting quality of such studies over the last decade according to the standards listed in the CONSORT and ARRIVE recommendations, respectively. Results: We noted a wide diversity in the study designs of animal studies in terms of diabetes induction. Major mismatches with the respective human studies referred to age and sex distribution, comorbidities, stage of the kidney disease, and selection of primary endpoints. Usually, treatment was initiated before onset of kidney disease without any standard of care as a background therapy. The reporting quality of animal studies was poor for randomization procedures, blinding, sample size calculation for a prespecified primary endpoint or the safety analysis. Reporting quality of clinical studies had deficits in trial design-, recruitment-, allocation-, and outcome-related aspects. Conclusion: Bench-to-bedside translation in the domain of DKD suffers from major deficits in the design of experimental studies in view of the projected clinical trials as well as from significant deficits in the reporting quality in preclinical and clinical studies.