Paralysis occurring in amyotrophic lateral sclerosis (ALS) results from denervation of skeletal muscle as a consequence of motor neuron degeneration. Interactions between motor neurons and glia ...contribute to motor neuron loss, but the spatiotemporal ordering of molecular events that drive these processes in intact spinal tissue remains poorly understood. Here, we use spatial transcriptomics to obtain gene expression measurements of mouse spinal cords over the course of disease, as well as of postmortem tissue from ALS patients, to characterize the underlying molecular mechanisms in ALS. We identify pathway dynamics, distinguish regional differences between microglia and astrocyte populations at early time points, and discern perturbations in several transcriptional pathways shared between murine models of ALS and human postmortem spinal cords.
Previous meta‐analyses of the relationship between phonological awareness (PA) and reading have been conducted mostly in children who speak English, a language with an opaque writing system. In this ...study, we present a meta‐analysis that examined mean correlations between three PA tasks testing phonemic, syllabic, and intrasyllabic awareness and three reading tasks testing word reading, nonword reading, and reading comprehension in Spanish, a language with a near‐transparent writing system. A random‐effects model of 47 articles (N = 7,956) was used for a multiple correlation study that showed a significantly moderate correlation between some of the PA subcategories and the reading tasks in Spanish‐speaking children. The largest correlation values were found between syllabic awareness and reading, which highlights the importance of syllable recognition during reading acquisition. In addition, we found that intrasyllabic awareness also plays an important role in reading in Spanish. The findings are discussed from a cross‐linguistic perspective.
Hydrogen (H2) is increasingly viewed as an attractive carbon-free fuel due to its potential compatibility with the existing transportation and conversion infrastructure. However, one of the major ...challenges facing large-scale deployment is the fundamentally different combustion properties it has in comparison to commonplace hydrocarbon fuels such as natural gas. For example, the laminar burning velocity (LBV) of a combustible mixture has a direct impact on how it can be used in internal combustion engine or gas turbines; the LBV of hydrogen is over 7 times greater than that of natural gas when combusted in air. Carbon dioxide (CO2) can be used as a working fluid, as opposed to nitrogen (in air), to reduce the flame speed of hydrogen combustion. A mixture of hydrogen, oxygen, and carbon dioxide as a working fluid can provide LBVs comparable to natural gas in air, which potentially enables existing conversion architectures. Furthermore, by replacing nitrogen (N2) with CO2 in the mixture, NOx emissions are avoided and opportunities for carbon sequestration or closed-cycle processes are possible. This study experimentally explores fundamental premixed oxy-combustion properties of H2-CO2 mixtures in a constant volume combustion chamber (CVCC) across a range of initial pressures (1, 1.5, and 2bar) and equivalence ratios (0.4, 0.6, 0.8, and 1). The spherically expanding flames are examined to determine the flame speed, LBV, and lower flammability limits (LFL) with respect to different CO2 concentrations (40%, 60%, 65%). Furthermore, at an initial pressure of 1bar and stoichiometric conditions, it was found that the flame speed of the 65% CO2 case was lower than that of CH4-air combustion.
•CO2 utilized as the working fluid in H2 oxy-combustion.•Implementable with existing conversion technologies, enables carbon sequestration.•Increasing the concentration of CO2 in the H2-O2-CO2 mixture lowers the LBV.•Extension of the lean flammability limits of H2-O2-CO2 mixtures with increased CO2%.
The aim of the present work is to show an approximation, through an experimental and a theoretical study, to quantify the mechanical losses in a turbocharging system. These are linked to the dynamics ...in the turbo shaft bearings, both axial and radial. Theoretical and experimental methodologies are presented in order to develop a mechanical losses model. The experimental work consists on a measurement campaign in quasi-adiabatic operating conditions, while in the theoretical part, a mathematical model is developed taking into account the radial and the axial bearings. The model uses some assumptions in order to solve the Navier–Stokes equations, leading to a simplified model which includes viscosity and the Reynolds number of the oil film formed on the bearings. The proposed model has shown a good agreement with the experimental data. This paper shows that for quasi-adiabatic conditions, having the turbocharger working at high speed; the mechanical efficiency could be assumed as a constant value close to unity. Nevertheless, the mechanical losses need to be computed for both journal and thrust bearing to get the best results. Although this must be confirmed, simple trends have been obtained when fitting coefficients of the model and basic geometrical parameters of the turbocharger.
•A quasi-adiabatic test campaign on three turbochargers has been performed in order to measure mechanical losses.•A simplified model of both thrust and journal bearing has been obtained from Navier–Stokes equations.•The model has been adjusted and validated with the measurements.•The main trends between the model parameters and basic geometrical data have been explained.
Coronavirus disease 2019 (COVID‐19) has been declared a pandemic. Peritoneal dialysis (PD), being a home therapy, allows for physical distancing measures and movement restrictions. In order to ...prevent COVID‐19 contagioun among the Dominican Republic National Health System PD program patients, a follow‐up virtual protocol for this group was developed. The aim of this study is to outline the protocol established by the PD program's healthcare team using telemedicine in order to avoid COVID‐19 transmission and to report initial results and outcomes of this initiative. This is an observational prospective longitudinal study with 946 patients being treated in seven centers distributed throughout the country between April 1 and June 30. The protocol was implemented focusing on the patient follow‐up; risk mitigation data were registered and collected from electronic records. During the follow‐up period, 95 catheters were implanted, 64 patients initiated PD, and the remaining were in training. A total of 9532 consultations were given by the different team specialists, with 8720 (91%) virtual and 812 (9%) face‐to‐face consultations. The transfer rate to hemodialysis was 0.29%, whereas the peritonitis rate was 0.11 episode per patient/year. Eighteen adults tested positive for COVID‐19. The implementation of the protocol and telemedicine utilization have ensured follow‐up and monitoring, preserved therapy, controlled complications, and PD lives protected.
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•The effect of ambient temperature on engine out emissions and DOC performance is analysed.•Experiments are carried out at two levels of ambient temperature (−7 °C and 20 °C) in ...WLTC.•HC emissions are 150% greater at low ambient temperatures.•Low ambient temperature dependence is detected in pollutants formation and DOC performance in case of CO.
In this paper an experimental analysis of the ambient temperature effect on diesel engine pollutant emissions is carried out. The study is focused on hydrocarbons and carbon monoxide of both engine out pollutants formation analysis and diesel oxidation catalyzer (DOC) performance. The experiments were carried out at transient engine load conditions of Worldwide harmonized Light vehicles Test Cycle (WLTC) at two levels of ambient temperature: 20 °C and −7 °C. The study presented in this work shows significant different results depending on the pollutant analysed. Regarding hydrocarbons, a significant dependence of pollutant formation on ambient temperature is observed, being the emissions at −7 °C between two and three times the emissions at 20 °C. The DOC performance between temperatures shows similar conversion efficiency. In the case of carbon monoxide formation, temperature dependence plays a less important role than the engine load conditions. The reduction of air fuel ratio at transient conditions drives to unsteady CO profiles emissions along the WLTC that reduce the pollutant conversion with a greater negative impact at −7 °C.
Fluorescence microscopy is a key method in the life sciences. State of the art -omics methods combine fluorescence microscopy with complex protocols to visualize tens to thousands of features in each ...of millions of pixels across samples. These -omics methods require precise control of temperature, reagent application, and image acquisition parameters during iterative chemistry and imaging cycles conducted over the course of days or weeks. Automated execution of such methods enables robust and reproducible data generation. However, few commercial solutions exist for temperature controlled, fluidics coupled fluorescence imaging, and implementation of bespoke instrumentation requires specialized engineering expertise. Here we present PySeq2500, an open source Python code base and flow cell design that converts the Illumina HiSeq 2500 instrument, comprising an epifluorescence microscope with integrated fluidics, into an open platform for programmable applications without need for specialized engineering or software development expertise. Customizable PySeq2500 protocols enable experimental designs involving simultaneous 4-channel image acquisition, temperature control, reagent exchange, stable positioning, and sample integrity over extended experiments. To demonstrate accessible automation of complex, multi-day workflows, we use the PySeq2500 system for unattended execution of iterative indirect immunofluorescence imaging (4i). Our automated 4i method uses off-the-shelf antibodies over multiple cycles of staining, imaging, and antibody elution to build highly multiplexed maps of cell types and pathological features in mouse and postmortem human spinal cord sections. Given the widespread availability of HiSeq 2500 platforms and the simplicity of the modifications required to repurpose these systems, PySeq2500 enables non-specialists to develop and implement state of the art fluidics coupled imaging methods in a widely available benchtop system.
IMPORTANCE: Financial incentives for weight management may increase use of evidence-based strategies while addressing obesity-related economic disparities in low-income populations. OBJECTIVE: To ...examine the effects of 2 financial incentive strategies developed using behavioral economic theory when added to provision of weight management resources. DESIGN, SETTING, AND PARTICIPANTS: Three-group, randomized clinical trial conducted from November 2017 to May 2021 at 3 hospital-based clinics in New York City, New York, and Los Angeles, California. A total of 1280 adults with obesity living in low-income neighborhoods were invited to participate, and 668 were enrolled. INTERVENTIONS: Participants were randomly assigned to goal-directed incentives, outcome-based incentives, or a resources-only group. The resources-only group participants were given a 1-year commercial weight-loss program membership, self-monitoring tools (digital scale, food journal, and physical activity monitor), health education, and monthly one-on-one check-in visits. The goal-directed group included resources and linked financial incentives to evidence-based weight-loss behaviors. The outcome-based arm included resources and linked financial incentives to percentage of weight loss. Participants in the incentive groups could earn up to $750. MAIN OUTCOMES AND MEASURES: Proportion of patients achieving 5% or greater weight loss at 6 months. RESULTS: The mean (SD) age of the 668 participants enrolled was 47.7 (12.4) years; 541 (81.0%) were women, 485 (72.6%) were Hispanic, and 99 (14.8%) were Black. The mean (SD) weight at enrollment was 98.96 (20.54) kg, and the mean body mass index (calculated as weight in kilograms divided by height in meters squared) was 37.95 (6.55). At 6 months, the adjusted proportion of patients who lost at least 5% of baseline weight was 22.1% in the resources-only group, 39.0% in the goal-directed group, and 49.1% in the outcome-based incentive group (difference, 10.08 percentage points 95% CI, 1.31-18.85 for outcome based vs goal directed; difference, 27.03 percentage points 95% CI, 18.20-35.86 and 16.95 percentage points 95% CI, 8.18-25.72 for outcome based or goal directed vs resources only, respectively). However, mean percentage of weight loss was similar in the incentive arms. Mean earned incentives was $440.44 in the goal-directed group and $303.56 in the outcome-based group, but incentives did not improve financial well-being. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, outcome-based and goal-directed financial incentives were similarly effective, and both strategies were more effective than providing resources only for clinically significant weight loss in low-income populations with obesity. Future studies should evaluate cost-effectiveness and long-term outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03157713
•The influence of the tip gap size on the tip leakage flow was analyzed by means of CFD.•Leading numbers for the tip leakage loss generation like flow momentum and velocity were modeled.•The model ...shows very good agreement with CFD data.•The developed correlations can easily be used to improve existing physically based loss models.•The correlations can further be used to predict trends during the turbine design and to estimate the impact of numerically assessing cold geometries.
The characterization of tip leakage flow plays an important role for one-dimensional loss modeling and design in radial turbine research. Tip leakage losses can be expressed as function of fluid momentum and mass flow passing through the tip gap. Friction-driven flow and contrariwise oriented pressure gradient-driven flow are highly coupled. However, these numbers are mostly unknown and dependent on tip gap geometry and turbine running condition. Based on a commonly used definition of a non-dimensional tip leakage momentum ratio, a novel correlation has been derived. This allows a consistent characterization for variable tip gap sizes over a wide range of operating conditions. The correlation has been validated by means of CFD data with high variety in reduced speed tip gap geometry and expansion ratios. Results of the novel number show significant improvements of quantitative and qualitative results over a wide range of running conditions in comparison to existing correlations. Furthermore, correlations for tip leakage velocities, that can easily be used in one-dimensional models, have been derived. Finally, it has been demonstrated, that the influence of inlet flow momentum on the tip leakage flow can be analyzed with presented correlations.
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