79 results match your criteria: "Institute for Critical Technology and Applied Science[Affiliation]"

Highly Efficient Electrode of Dirac Semimetal PtTe for MoS-Based Field Effect Transistors.

ACS Appl Mater Interfaces

December 2024

Beijing Academy of Quantum Information Sciences, Beijing 100193, China.

Two-dimensional van der Waals (vdW) layered materials not only are an intriguing fundamental scientific research platform but also provide various applications to multifunctional quantum devices in the field-effect transistors (FET) thanks to their excellent physical properties. However, a metal-semiconductor (MS) interface with a large Schottky barrier causes serious problems for unleashing their intrinsic potentials toward the advancements in high-performance devices. Here, we show that exfoliated vdW Dirac semimetallic PtTe can be an excellent electrode for electrons in MoS FETs.

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How Shell Add-On Products Influence Varsity Football Helmet Performance?

Ann Biomed Eng

November 2024

Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, USA.

Article Synopsis
  • The study aimed to evaluate the performance of three shell add-on products for helmets under varsity-level impact conditions through laboratory tests.
  • Pendulum impact tests measured head kinematics and concussion risk with different helmet models and configurations to assess each add-on's effectiveness.
  • Results showed that the Guardian NXT add-on significantly reduced peak linear acceleration, peak rotational acceleration, and concussion risk more than the other two products, emphasizing the importance of helmet model selection for improved head protection.
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Background: Neck pain in a concussion population is an emerging area of study that has been shown to have a negative influence on recovery. This effect has not yet been studied in collegiate athletes.

Hypothesis: New or worsened neck pain is common after a concussion (>30%), negatively influences recovery, and is associated with patient sex and level of contact in sport.

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The Influence of Headform Friction and Inertial Properties on Oblique Impact Helmet Testing.

Ann Biomed Eng

October 2024

Department of Biomedical Engineering and Mechanics, Virginia Tech, 120 Kelly Hall, 325 Stanger Street MC 0298, Blacksburg, VA, 24061, USA.

Helmet-testing headforms replicate the human head impact response, allowing the assessment of helmet protection and injury risk. However, the industry uses three different headforms with varying inertial and friction properties making study comparisons difficult because these headforms have different inertial and friction properties that may affect their impact response. This study aimed to quantify the influence of headform coefficient of friction (COF) and inertial properties on oblique impact response.

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The use of 3D printing technologies by industry and consumers is expanding. However, the approaches to assess the risk of lung carcinogenesis from the emissions of 3D printers have not yet been developed. The objective of the study was to demonstrate a methodology for modeling lung cancer risk related to specific exposure levels as derived from an experimental study of 3D printer emissions for various types of filaments (ABS, PLA, and PETG).

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Background: Molecular-based approaches to understanding concussion pathophysiology provide complex biological information that can advance concussion research and identify potential diagnostic and/or prognostic biomarkers of injury.

Objective: The aim of this study was to identify gene expression changes in peripheral blood that are initiated following concussion and are relevant to concussion response and recovery.

Methods: We analyzed whole blood transcriptomes in a large cohort of concussed and control collegiate athletes who were participating in the multicenter prospective cohort Concussion Assessment, Research, and Education (CARE) Consortium study.

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Engineered live bacteria as disease detection and diagnosis tools.

J Biol Eng

October 2023

Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA, 24061, USA.

Sensitive and minimally invasive medical diagnostics are essential to the early detection of diseases, monitoring their progression and response to treatment. Engineered bacteria as live sensors are being developed as a new class of biosensors for sensitive, robust, noninvasive, and in situ detection of disease onset at low cost. Akin to microrobotic systems, a combination of simple genetic rules, basic logic gates, and complex synthetic bioengineering principles are used to program bacterial vectors as living machines for detecting biomarkers of diseases, some of which cannot be detected with other sensing technologies.

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Identification and quantification of Cr, Cu, and As incidental nanomaterials derived from CCA-treated wood in wildland-urban interface fire ashes.

J Hazard Mater

March 2023

Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina, United States. Electronic address:

Article Synopsis
  • WUI fires burn treated wood, releasing harmful elements like chromium, copper, and arsenic found in the ashes of structures.
  • The study uses advanced techniques (ICP-TOF-MS and TEM) to analyze both the elemental concentrations and the crystalline phases of these elements in ash samples.
  • Findings reveal that chromium, copper, and arsenic are the dominant components in the ashes, with specific molecular associations and ratios, indicating significant release of toxic substances during such fires.
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Activated carbon fibers (ACFs) as one of the most important porous carbon materials are widely used in many applications that involve rapid adsorption and low-pressure loss, including air purification, water treatment, and electrochemical applications. For designing such fibers for the adsorption bed in gas and aqueous phases, in-depth comprehension of the surface components is crucial. However, achieving reliable values remains a major challenge due to the high adsorption affinity of ACFs.

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Wildland-urban interface fire ashes as a major source of incidental nanomaterials.

J Hazard Mater

February 2023

Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC 29201, United States. Electronic address:

Although metal and metalloid concentrations in wildfire ashes have been documented, the nature and concentrations of incidental nanomaterials (INMs) in wildland-urban interface (WUI) fire ashes have received considerably less attention. In this study, the total metal and metalloid concentrations of 57 vegetation, structural, and vehicle ashes and underlying soils collected at the WUI following the 2020 fire season in northern California - North Complex Fire and LNU Lightning Complex Fire - were determined using inductively coupled plasma-time of flight-mass spectrometry after microwave-assisted acid digestion. The concentrations of Ti, Zn, Cu, Ni, Pb, Sn, Sb, Co, Bi, Cr, Ba, As, Rb, and W are generally higher in structural/vehicle-derived ashes than in vegetation-derived ashes and soils.

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The gut microbiome of wild American marten in the Upper Peninsula of Michigan.

PLoS One

November 2022

Michigan Department of Natural Resources, Marquette, Michigan, United States of America.

Carnivores are ecologically important and sensitive to habitat loss and anthropogenic disruption. Here we measured trophic level and gut bacterial composition as proxies of carnivore ecological status across the Upper Peninsula, Michigan, for wild American marten (Martes americana; hereafter marten). In contrast to studies that have focused on omnivorous and herbivorous species, we find that marten, like other carnivore species without a cecum, are dominated by Firmicutes (52.

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It is critical to thoroughly investigate, characterize, and understand the unique emission profiles of common and novel polymer feedstocks used in fused filament fabrication (FFF) 3D printers as these products become increasingly ubiquitous in consumer and industrial environments. This work contributes unique insights regarding the effects of polymer composite feedstocks with metal, ceramic, or carbonaceous particle additives on particulate emissions in a variety of filaments under various print conditions, including print temperature. In addition to active characterization of particulate size and concentration following the ANSI/CAN/UL 2904 method, particulate sampling and subsequent analysis by scanning electron microscopy revealed agglomeration behavior that may have important health implications.

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Biohybrid robots: recent progress, challenges, and perspectives.

Bioinspir Biomim

November 2022

Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering and School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, United States of America.

The past ten years have seen the rapid expansion of the field of biohybrid robotics. By combining engineered, synthetic components with living biological materials, new robotics solutions have been developed that harness the adaptability of living muscles, the sensitivity of living sensory cells, and even the computational abilities of living neurons. Biohybrid robotics has taken the popular and scientific media by storm with advances in the field, moving biohybrid robotics out of science fiction and into real science and engineering.

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Exceptional power conversion efficiency (PCE) of 25.7% in perovskite solar cells (PSCs) has been achieved, which is comparable with their traditional rivals (Si-based solar cells). However, commercialization-worthy efficiency and long-term stability remain a challenge.

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Graphene is of great interest for many far-reaching applications that involve interparticle interactions in adsorbents, coatings, and composites. A deep understanding of the surface components has been crucial but achieving the most accurate and reliable values of these, unaffected by experimental conditions or the analytical techniques used, remains a major challenge. To this end, we have proposed in this paper a novel approach for the first time, to the best of our knowledge, to determine London dispersive and specific (polar) components including the Lewis acid-base character of the surface free energy of graphene materials (graphene oxide (GO), reduced graphene oxide (rGO), and graphite) using inverse gas chromatography (IGC) technique at an infinite dilution.

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Despite advances in the understanding of human tolerances to brain injury, injury metrics used in automotive safety and protective equipment standards have changed little since they were first implemented nearly a half-century ago. Although numerous metrics have been proposed as improvements over the ones currently used, evaluating the predictive capability of these metrics is challenging. The purpose of this review is to summarize existing head injury metrics that have been proposed for both severe head injuries, such as skull fractures and traumatic brain injuries (TBI), and mild traumatic brain injuries (mTBI) including concussions.

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Trace metals rarely contaminate freshwaters independently, hence regulatory limits based on single-metal toxicity may be underprotective of aquatic life. This could be especially the case for rare and sensitive fauna like freshwater mussels, such as those suppressed in the Clinch and Powell Rivers in eastern USA where trace metals are long-term contaminants but at concentrations below regulatory limits. We hypothesized metal mixtures may be exerting combined effects on mussels, resulting in greater toxicity than would be predicted based on single-metal exposures.

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Indoor flooding is a leading contributor to indoor dampness and the associated mold infestations in the coastal United States. Whether the prevalent mold genera that infest the coastal flood-prone buildings are different from those not flood-prone is unknown. In the current case study of 28 mold-infested buildings across the U.

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Drones have been increasing in popularity and are able to cause skin injuries ranging from minor abrasions to severe lacerations. The objective of this study was to determine the aspects of drone blades that cause injuries, and to help manufacturers design safer drones by suggesting an injury threshold. The blade tip thickness, blade length, angular velocity, and blade tip speed of a variety of popular drones were measured.

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Fused filament fabrication (FFF) 3D printers are increasingly used in industrial, academic, military, and residential sectors, yet their emissions and associated user exposure scenarios are not fully described. Characterization of potential user exposure and environmental releases requires robust investigation. During operation, common FFF 3D printers emit varying amounts of ultrafine particles (UFPs) depending upon feedstock material and operation procedures.

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Shear-deformation based continuum-damage constitutive modeling of brain tissue.

J Biomech

March 2021

Tissue Mechanics, Microstructure, and Modeling Laboratory, Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, United States. Electronic address:

Traumatic brain injury (TBI) is a leading cause of death in the United States. Depending on the severity of injury, complications such as memory loss and emotional changes are common. While the exact mechanisms are still unclear, these cognitive deficiencies are thought to arise from microstructural damages to the brain tissue, such as in diffuse-axonal injury where neuron fibers are sheared.

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