ABSTRACT
Mammalian hair cells (HCs) are arranged spirally along the cochlear axis and correspond to different frequency ranges. Serving as primary sound detectors, HCs spatially segregate component frequencies into a topographical map. HCs display significant diversity in anatomical and physiological characteristics, yet little is known about the organization of the cochleotopic map of HCs or the molecules involved in this process. Using single-cell RNA sequencing, we determined the distinct molecular profiles of inner hair cells and outer hair cells, and we identified numerous position-dependent genes that were expressed as gradients. Newly identified genes such as Ptn, Rxra, and Nfe2l2 were found to be associated with tonotopy. We employed the SCENIC algorithm to predict the transcription factors that potentially shape these tonotopic gradients. Furthermore, we confirmed that Nfe2l2, a tonotopy-related transcription factor, is critical in mice for sensing low-to-medium sound frequencies in vivo. the analysis of cell-cell communication revealed potential receptor-ligand networks linking inner hair cells to spiral ganglion neurons, including pathways such as BDNF-Ntrk and PTN-Scd4, which likely play essential roles in tonotopic maintenance. Overall, these findings suggest that molecular gradients serve as the organizing principle for maintaining the selection of sound frequencies by HCs.
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INTRODUCTION: Speed is a primary contributing factor in teenage driver crashes. Yet, there are significant methodological challenges in measuring real-world speeding behavior. METHOD: This case study approach analyzed naturalistic driving data for six teenage drivers in a longitudinal study that spanned the learner and early independent driving stages of licensure in Maryland, United States. Trip duration, travel speed and length were recorded using global position system (GPS) data. These were merged with maps of the Maryland road system, which included posted speed limit (PSL) to determine speeding events in each recorded trip. Speeding was defined as driving at the speed of 10 mph higher than the posted speed limit and lasting longer than 6 s. Using these data, two different speeding measures were developed: (1) Trips with Speeding Episodes, and (2) Verified Speeding Time. Conclusions & Practical Applications: Across both measures, speeding behavior during independent licensure was greater than during the learner period. These measures improved on previous methodologies by using PSL information and eliminating the need for mapping software. This approach can be scaled for use in larger samples and has the potential to advance understanding about the trajectory of speeding behaviors among novice teenage drivers.
Subject(s)
Automobile Driving , Adolescent , Humans , United States , Accidents, Traffic/prevention & control , Longitudinal Studies , Risk-Taking , TravelABSTRACT
Background: Under-resourced urban minority communities in the United States are characterized by food environments with low access to healthy foods, high food insecurity, and high rates of diet-related chronic disease. In Baltimore, Maryland, low access to healthy food largely results from a distribution gap between small food sources (retailers) and their suppliers. Digital interventions have the potential to address this gap, while keeping costs low. Methods: In this paper, we describe the technical (I) front-end design and (II) back-end development process of the Baltimore Urban food Distribution (BUD) application (app). We identify and detail four main phases of the process: (I) information architecture; (II) low and high-fidelity wireframes; (III) prototype; and (IV) back-end components, while considering formative research and a pre-pilot test of a preliminary version of the BUD app. Results: Our lessons learned provide valuable insight into developing a stable app with a user-friendly experience and interface, and accessible cloud computing services for advanced technical features. Conclusions: Next steps will involve a pilot trial of the app in Baltimore, and eventually, other urban and rural settings nationwide. Once iterative feedback is incorporated into the app, all code will be made publicly available via an open source repository to encourage adaptation for desired communities. Trial Registration: ClinicalTrials.gov NCT05010018.
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This work proposes a strategy to address the challenge of achieving rapid reprocessability of vitrimers at mild temperatures by introducing dynamic disulfide and hemiaminal bonds into hemiaminal dynamic covalent networks (HDCNs). The resulting HDCNs, termed HDCNs-DTDA, were prepared through a facile polycondensation between formaldehyde and 4,4'-dithiodianiline. The dual dynamic bond system in the HDCNs-DTDA enables rapid stress relaxation under mild temperature (65 °C for 54 s), which is significantly faster than that observed in HDCNs containing a single dynamic bond (HDCNs-DDM). The HDCNs-DTDA also exhibit a glass transition temperature of 96 °C, excellent solvent resistance and high recovery rates (97%) of tensile strength after reprocessing. In addition, HDCNs-DTDA can be easily degraded in HCl and thiol solutions at room temperature to enable chemical recyclability. Finally, HDCNs-DTDA demonstrates fast shape memory behaviors using thermal stimulation.
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Native American populations experience highly disproportionate rates of poor maternal-child health outcomes. The WIC program aims to safeguard health by providing greater access to nutritious foods, but for reasons not well understood, participation in many tribally-administered WIC programs has declined to a greater extent compared to the national average decline in participation over the last decade. This study aims to examine influences on WIC participation from a systems perspective in two tribally-administered WIC programs. In-depth interviews were conducted with WIC-eligible individuals, WIC staff, tribal administrators, and store owners. Interview transcripts underwent qualitative coding, followed by identifying causal relationships between codes and iterative refining of relationships using Kumu. Two community-specific causal loop diagrams (CLDs) were developed and compared. Findings from interviews in the Midwest yielded a total of 22 factors connected through 5 feedback loops, and in the Southwest a total of 26 factors connected through 7 feedback loops, resulting in three overlapping themes: Reservation and Food Store Infrastructure, WIC Staff Interactions and Integration with the Community, and State-level Administration and Bureaucracy. This study demonstrates the value of a systems approach to explore interconnected barriers and facilitators that can inform future strategies and mitigate declines in WIC participation.
Subject(s)
Food Assistance , Humans , Infant , Poverty , Systems AnalysisABSTRACT
Lymphoplasmacyte-rich meningioma (LPRM) is a rare subtype of meningioma, the specific pathogenesis of which remains unclear. Herein, we report the case of a 48-year-old Asian man who experienced progressive deafness and limb weakness. Magnetic resonance imaging revealed extramedullary masses diffusely growing, wrapping, and compressing the cervical spinal cord. The dural lesion was partially excised by surgery, and postoperative pathological examination confirmed the diagnosis of LPRM. Diffuse LPRM is extremely rare, and its treatment is challenging owing to difficulties associated with surgery and the uncertain efficacy of traditional therapies. Therefore, further clinical practice and basic research are needed to improve the prognosis of diffuse LPRM.
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Low-income urban communities in the United States commonly lack ready access to healthy foods. This is due in part to a food distribution system that favors the provision of high-fat, high-sugar, high-sodium processed foods to small retail food stores, and impedes their healthier alternatives, such as fresh produce. The Baltimore Urban food Distribution (BUD) study is a multilevel, multicomponent systems intervention that aims to improve healthy food access in low-income neighborhoods of Baltimore, Maryland. The primary intervention is the BUD application (app), which uses the power of collective purchasing and delivery to affordably move foods from local producers and wholesalers to the city's many corner stores. We will implement the BUD app in a sample of 38 corner stores, randomized to intervention and comparison. Extensive evaluation will be conducted at each level of the intervention to assess overall feasibility and effectiveness via mixed methods, including app usage data, and process and impact measures on suppliers, corner stores, and consumers. BUD represents one of the first attempts to implement an intervention that engages multiple levels of a local food system. We anticipate that the app will provide a financially viable alternative for Baltimore corner stores to increase their stocking and sales of healthier foods, subsequently increasing healthy food access and improving diet-related health outcomes for under-resourced consumers. The design of the intervention and the evaluation plan of the BUD project are documented here, including future steps for scale-up. Trial registration #: NCT05010018.
Subject(s)
Food Supply , Mobile Applications , Baltimore , Commerce , Feasibility Studies , Health Promotion/methods , Randomized Controlled Trials as Topic , United StatesABSTRACT
BACKGROUND: Therapeutic bronchoscopy is one of the effective methods in the treatment and management of malignant central airway stenosis (MCAS). However, restenosis after therapeutic bronchoscopy frequently occurs and severe restenosis (SR) can be life-threatening. Therefore, this study aimed at investigating the risk factors for SR after therapeutic bronchoscopy. METHODS: The data of 233 consecutive cases with MCAS who were subjected to therapeutic bronchoscopy between 2015 and 2020 at a tertiary hospital were collected. Patients were divided into SR group and non-SR during 6 months after therapeutic bronchoscopy. Multiple logistic regression analysis was performed to determine the risk factors for SR. RESULTS: SR during 6 months after therapeutic bronchoscopy occurred in 39.5% (92/233) of patients. The location and the initial degree of MCAS were associated with SR, as assessed by multiple logistic regression analysis (P < 0.05). The risk of SR after therapeutic bronchoscopy in the left main bronchus, right main bronchus, and right intermediate bronchus increased, compared to the risk when of MCAS was located in the trachea (OR (95% CI) of 8.821 (1.850-25.148), 6.583 (1.791-24.189), and 3.350 (0.831-13.511), respectively). In addition, the initial degree of MCAS was positively associated with an increased risk of SR (OR 1.020; 95% CI 1.006-1.035). CONCLUSIONS: MCAS located in the left main bronchus, right main bronchus and right intermediate bronchus, as well as the higher initial degree of MCAS were independent risk factors for SR during 6 months after therapeutic bronchoscopy.
Subject(s)
Bronchi/pathology , Bronchoscopy , Constriction, Pathologic/surgery , Lung Neoplasms/surgery , Aged , Aged, 80 and over , Bronchi/surgery , China , Constriction, Pathologic/complications , Female , Humans , Lung Neoplasms/complications , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasms, Squamous Cell/pathology , Recurrence , Retrospective Studies , Risk FactorsABSTRACT
Policy interventions to improve food access and address the obesity epidemic among disadvantaged populations are becoming more common throughout the United States. In Baltimore MD, corner stores are a frequently used source of food for low-income populations, but these stores often do not provide a range of affordable healthy foods. This research study aimed to assist city policy makers as they considered implementing a Staple Food Ordinance (SFO) that would require small stores to provide a range and depth of stock of healthy foods. A System Dynamics (SD) model was built to simulate the complex Baltimore food environment and produce optimal values for key decision variables in SFO planning. A web-based application was created for users to access this model to optimize future SFOs, and to test out different options. Four versions of potential SFOs were simulated using this application and the advantages and drawbacks of each SFO are discussed based on the simulation results. These simulations show that a well-designed SFO has the potential to reduce staple food costs, increase corner store profits, reduce food waste, and expand the market for heathy staple foods.
Subject(s)
Diet, Healthy/methods , Nutrition Policy/economics , Obesity/prevention & control , Supermarkets , Baltimore , Food Supply , Humans , Marketing , Nutrition Policy/legislation & jurisprudence , PovertyABSTRACT
The potential airborne transmission of SARS-CoV-2 has triggered concerns as schools continue to reopen and resume in-person instruction during the current COVID-19 pandemic. It is critical to understand the risks of airborne SARS-CoV-2 transmission under different epidemiological scenarios and operation strategies for schools to make informed decisions to mitigate infection risk. Through scenario-based analysis, this study estimates the airborne infection risk of SARS-CoV-2 in 111,485 U.S. public and private schools and evaluates the impacts of different intervention strategies, including increased ventilation, air filtration, and hybrid learning. Schools in more than 90% of counties exhibit infection risk of higher than 1%, indicating the significance of implementing intervention strategies. Among the considered strategies, air filtration is found to be most effective: the school average infection risk when applying MERV 13 is over 30% less than the risk levels correlating with the use of increased ventilation and hybrid learning strategies, respectively. For most schools, it is necessary to adopt combined intervention strategies to ensure the infection risk below 1%. The results provide insights into airborne infection risk in schools under various scenarios and may guide schools and policymakers in developing effective operations strategies to maintain environmental health.
ABSTRACT
Developing recyclable, reworkable, and intelligent thermosetting polymers, as a long-standing challenge, is highly desirable for modern manufacturing industries. Herein, we report a polyhexahydrotriazine thermoset (PHT) prepared by a one-pot polycondensation between 4-aminophenyl disulfide and paraformaldehyde. The PHT has a glass transition temperature of 135 °C and good solvent resistance. The incorporation of dual stimuli-responsive groups (disulfide bond and hexahydrotriazine ring) endows the PHT with re-processability, re-workability, and damage monitoring function. The PHT can be repeatedly reprocessed by hot pressing, and a near 100% recovery of flexural strength is achieved. The PHT can also degrade in inorganic acid or organic thiol solutions at room temperature. The thermally reworkable test demonstrates that, after heating the PHT at 200 °C for 1 h, the residuals can be easily wiped off. Finally, the PHT exhibits a reversible mechanochromic behavior when damaged.
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Diabetic foot is a common and serious complication of diabetes, largely due to sensory neuropathy and excessive mechanical stresses. Studies have shown that reducing the contact pressure can effectively lower the incidence of diabetic foot. A new design method is proposed in this study for optimizing the stress distribution of the contact surfaces between the foot and the insole by applying functional gradient structural properties to the insole. Finite element analysis was employed for studying the contact mechanics, which laid the foundation for modulus readjustment during the optimization process. The moduli of the materials were correlated to the properties of the structural porous units. The customized insoles were manufactured using additive manufacturing technology and put into mechanical test. Results show that the designed insole helps in increasing the foot contact area by approximately 30% and reducing the peak contact pressure by 35%. Hence, the proposed method can be used to design customized insoles, particularly diabetic insoles, by offering better contact mechanics and good potential for reducing the severity of diabetic foot. The methodology is equally applicable to other designs involving optimization of material properties.
Subject(s)
Diabetic Foot , Equipment Design , Shoes , Finite Element Analysis , Humans , PorosityABSTRACT
Toxic metals are usually present as organic complexes in high-salinity effluents from various industries. The efficient removal of such metal complexes is an imperative but still challenging task due to their stable structure and high mobility. Herein, we propose a new strategy to remove Cu-carboxyl complexes from high-salinity water by using a commercially available nanocomposite HZO-201, i.e., nanohydrated zirconium oxide (HZO) confined inside anion exchanger D201. In contrast to D201 and a cation exchanger D001, which both adsorb Cu-citrate negligibly, HZO-201 exhibits preferable adsorption toward Cu-citrate (â¼130 mg Cu/g-Zr) at high salinity (1.5 wt % NaCl). On the basis of scanning transmission electron microscopy energy-dispersive spectrometry (STEM-EDS), attenuated total reflection Fourier transform infrared (ATR-FTIR), and X-ray photoelectron spectrometry (XPS) analysis, the formation of ternary complex among Cu(II), citrate, and the embedded nano-HZO is evidenced to be responsible for the removal of Cu-citrate. The exhausted HZO-201 can be regenerated with a binary HCl-NaCl solution for repeated use for 5 cycles without capacity loss. Fixed-bed adsorption demonstrates that HZO-201 column is capable of producing â¼1150 bed volume (BV) clean water (<0.5 mg Cu/L) from simulated high-salinity wastewater, whereas only â¼10 BV and â¼60 BV was produced for the D001 and D201 columns, respectively. Furthermore, HZO-201 shows excellent removal of Cu(II) complexes with three other carboxyl ligands (oxalate, tartrate, and succinate).