The employment of resuscitative endovascular balloon occlusion of the aorta in deployed settings.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been often used in place of open aortic occlusion for management of hemorrhagic shock in trauma. There is a paucity of data evaluating REBOA usage in military settings. STUDY DESIGN AND METHODS: We queried the Department of Defense Trauma Registry (DODTR) for all cases with at least one intervention or assessment available within the first 72 h after injury between 2007 and 2023. We used relevant procedural codes to identify the use of REBOA within the DODTR, and we used descriptive statistics to characterize its use. RESULTS: We identified 17 cases of REBOA placed in combat settings from 2017 to 2019. The majority of these were placed in the operating room (76%) and in civilian patients (70%). A penetrating mechanism caused the injury in 94% of cases with predominantly the abdomen and extremities having serious injuries. All patients subsequently underwent an exploratory laparotomy after REBOA placement, with moderate numbers of patients having spleen, liver, and small bowel injuries. The majority (82%) of included patients survived to hospital discharge. DISCUSSION: We describe 17 cases of REBOA within the DODTR from 2007 to 2023, adding to the limited documentation of patients undergoing REBOA in military settings. We identified patterns of injury in line with previous studies of patients undergoing REBOA in military settings. In this small sample of military casualties, we observed a high survival rate.

Orientation of reduced graphene oxide in composite coatings.

Composite coatings containing reduced graphene oxide (rGO) and 3-(aminopropyl)triethoxysilane functionalised rGO (APTES-rGO) were prepared by sol-gel technology and deposited on Al 2024 T-3. Covalent functionalisation of GO by APTES occurred by formation of amide bonds, accompanied by GO reduction. The thin sheets were retained. The hydrophilicity of the coating increased when APTES-rGO was added. The opposite was observed when GO was added. A key finding is that the rGO flakes agglomerate and lie in a random orientation in the coating, whereas the APTES-rGO flakes are more evenly distributed in the matrix and appear to lie along the plane of the substrate.

Gas Sensing Properties of PLD Grown 2D SnS Film: Effect of Film Thickness, Metal Nanoparticle Decoration, and In Situ KPFM Investigation.

This study employs novel growth methodologies and surface sensitization with metal nanoparticles to enhance and manipulate gas sensing behavior of two-dimensional (2D)SnS film. Growth of SnS films is optimized by varying substrate temperature and laser pulses during pulsed laser deposition (PLD). Thereafter, palladium (Pd), gold (Au), and silver (Ag) nanoparticles are decorated on as-grown film using gas-phase synthesis techniques. X-ray diffraction (XRD), Raman spectroscopy, and Field-emission scanning electron microscopy (FESEM) elucidate the growth evolution of SnS and the effect of nanoparticle decoration. X-ray photoelectron spectroscopy (XPS) analyses the chemical state and composition. Pristine SnS, Ag, and Au decorated SnS films are sensitive and selective toward NO2 at room temperature (RT). Ag nanoparticle increases the response of pristine SnS from 48 to 138% toward 2 ppm NO2, which indicates electronic and chemical sensitization effect of Ag. Pd decoration on SnS tunes its selectivity toward H2 gas with a response of 55% toward 70 ppm H2 and limit of detection (LOD) < 1 ppm. In situ Kelvin probe force microscopy (KPFM) maps the work function changes, revealing catalytic effect of Ag toward NO2 in Ag-decorated SnS and direct charge transfer between Pd and SnS during H2 exposure in Pd-decorated SnS.

Phonon-Mediated Quasiparticle Lifetime Renormalizations in Few-Layer Hexagonal Boron Nitride.

Understanding the collective behavior of the quasiparticles in solid-state systems underpins the field of nonvolatile electronics, including the opportunity to control many-body effects for well-desired physical phenomena and their applications. Hexagonal boron nitride (hBN) is a wide-energy-bandgap semiconductor, showing immense potential as a platform for low-dimensional device heterostructures. It is an inert dielectric used for gated devices, having a negligible orbital hybridization when placed in contact with other systems. Despite its inertness, we discover a large electron mass enhancement in few-layer hBN affecting the lifetime of the π-band states. We show that the renormalization is phonon-mediated and consistent with both single- and multiple-phonon scattering events. Our findings thus unveil a so-far unknown many-body state in a wide-bandgap insulator, having important implications for devices using hBN as one of their building blocks.

Plasmonic properties of aluminium nanowires in amorphous silicon.

Plasmonic structures can help enhance optical activity in the ultraviolet (UV) region and therefore enhancing photocatalytic reactions and the detection of organic and biological species. Most plasmonic structures are composed of Ag or Au. However, producing structures small enough for optical activity in the UV region has proved difficult. In this study, we demonstrate that aluminium nanowires are an excellent alternative. We investigated the plasmonic properties of the Al nanowires as well as the optoelectronic properties of the surroundinga - Simatrix by combining scanning transmission electron microscopy imaging, electron energy loss spectroscopy and electrodynamic modelling. We have found that the Al nanowires have distinct plasmonic modes in the UV and far UV region, from 0.75 eV to 13 eV. In addition, simulated results found that the size and spacing of the Al nanowires, as well as the embedding material were shown to have a large impact on the type of surface plasmon energies that can be generated in the material. Using electromagnetic modelling, we have identified the modes and illustrated how they could be tuned further.

Tailoring the Vertical and Planar Growth of 2D WS2 Thin Films Using Pulsed Laser Deposition for Enhanced Gas Sensing Properties.

In this study, pulsed laser deposition has been utilized for the controllable synthesis of WS2 thin films with growth orientation ranging from vertically to horizontally aligned layers, and the effect of growth parameters has been investigated. The growth of thin films on SiO2 substrates at three different pressures (30, 50, and 70 mTorr) and three different temperatures (400, 500, and 600 °C) has been studied. Detailed characterizations carried out on the as-grown layers clearly show the formation of the 2H-WS2 phase and its morphological evolution with deposition conditions. Atomic force microscopy and cross-sectional transmission electron microscopy have been used to deduce the growth mechanism of the vertical and planar films with different deposition parameters. The samples grown with a combination of lower temperatures and higher pressures exhibit a vertical flake-like growth with a flake thickness of ∼2-5 nm. However, at higher temperatures and lower pressures, the film growth is observed to be rather planar. The gas sensing parameters and the underlying mechanism have been observed to be quite different for vertically and horizontally grown layers. The vertical layers showed a selective response toward NO2 gas at room temperature (RT) with a limit of detection less than 50 ppb. In comparison, a very subdued and poor gas sensing response was recorded for the planar film at RT. A large specific area and abundance of active edge sites along with the flat basal plane present in the vertically grown layers seem to be responsible for efficient gas sensing toward NO2.

Advanced partial occlusion controller allows for increased precision during targeted regional optimization in a porcine model of hemorrhagic shock.

BACKGROUND: Targeted regional optimization (TRO), a partial resuscitative endovascular balloon occlusion of the aorta strategy, may mitigate distal ischemia and extend the window of effectiveness for this adjunct. An automated device may allow greater control and precise regulation of flow past the balloon, while being less resource-intensive. The objective of this study was to assess the technical feasibility of the novel advanced partial occlusion controller (APOC) in achieving TRO at multiple distal pressures. METHODS: Female swine (n = 48, 68.1 ± 0.7 kg) were randomized to a target distal mean arterial pressure (MAP) of 25 mm Hg, 35 mm Hg, or 45 mm Hg by either manual (MAN) or APOC regulation (n = 8 per group). Uncontrolled hemorrhage was generated by liver laceration. Targeted regional optimization was performed for 85 minutes, followed by surgical control and a 6-hour critical care phase. Proximal and distal MAP and flow rates were measured continuously. RESULTS: At a target distal MAP of 25 mm Hg, there was no difference in the MAP attained (APOC: 26.2 ± 1.05 vs. MAN: 26.1 ± 1.78 mm Hg) but the APOC had significantly less deviance (10.9%) than manual titration (14.9%, p < 0.0001). Similarly, at a target distal MAP of 45 mm Hg, there was no difference in mean pressure (44.0 ± 0.900 mm Hg vs. 45.2 ± 1.31 mm Hg) but APOC had less deviance (9.34% vs. 11.9%, p < 0.0001). There was no difference between APOC and MAN in mean (34.6 mm Hg vs. 33.7 mm Hg) or deviance (9.95% vs. 10.4%) at a target distal MAP of 35 mm Hg, respectively. The APOC made on average 77 balloon volume adjustments per experiment compared with 29 by manual titrations. CONCLUSION: The novel APOC consistently achieved and sustained precisely regulated TRO across all groups and demonstrated reduced deviance at the 25 mm Hg and 45 mm Hg groups compared with manual titration.

Vertical field-effect transistor based on graphene-WS2 heterostructures for flexible and transparent electronics.

The celebrated electronic properties of graphene have opened the way for materials just one atom thick to be used in the post-silicon electronic era. An important milestone was the creation of heterostructures based on graphene and other two-dimensional crystals, which can be assembled into three-dimensional stacks with atomic layer precision. Such layered structures have already demonstrated a range of fascinating physical phenomena, and have also been used in demonstrating a prototype field-effect tunnelling transistor, which is regarded to be a candidate for post-CMOS (complementary metal-oxide semiconductor) technology. The range of possible materials that could be incorporated into such stacks is very large. Indeed, there are many other materials with layers linked by weak van der Waals forces that can be exfoliated and combined together to create novel highly tailored heterostructures. Here, we describe a new generation of field-effect vertical tunnelling transistors where two-dimensional tungsten disulphide serves as an atomically thin barrier between two layers of either mechanically exfoliated or chemical vapour deposition-grown graphene. The combination of tunnelling (under the barrier) and thermionic (over the barrier) transport allows for unprecedented current modulation exceeding 1 × 10(6) at room temperature and very high ON current. These devices can also operate on transparent and flexible substrates.

Electron tunneling through ultrathin boron nitride crystalline barriers.

We investigate the electronic properties of ultrathin hexagonal boron nitride (h-BN) crystalline layers with different conducting materials (graphite, graphene, and gold) on either side of the barrier layer. The tunnel current depends exponentially on the number of h-BN atomic layers, down to a monolayer thickness. Conductive atomic force microscopy scans across h-BN terraces of different thickness reveal a high level of uniformity in the tunnel current. Our results demonstrate that atomically thin h-BN acts as a defect-free dielectric with a high breakdown field. It offers great potential for applications in tunnel devices and in field-effect transistors with a high carrier density in the conducting channel.

Bisphenol A concentrations in receiving waters near US manufacturing and processing facilities.

Bisphenol A (BPA) (CAS 80-05-7) was analyzed in receiving waters upstream and downstream of US manufacturers (1996 and 1997) and processors (1997) during seasonal low flow periods. BPA was not detected (< 1 microgram/l) in any surface water sample in 1996 or at six of seven sites in 1997. Concentrations near the seventh site ranged from 2 to 8 micrograms/l; however, its receiving stream had no measurable flow and concentrations represent undiluted effluent. All surface water concentrations from this and other studies were less than the freshwater predicted no effect concentration (PNEC) of 64 micrograms/l, suggesting that BPA discharges from manufacturing and processing facilities to surface water do not pose an environmental concern.

Dermal undermining (scarification) of active rhytids and scars: enhancing the results of CO(2) laser skin resurfacing.

Active and passive rhytids develop as part of the aging process. Active rhytids become more prominent with facial animation. Efficacy of CO(2) laser resurfacing for active rhytids is enhanced by scarifying beneath the active rhytid before resurfacing. Scarification can be performed with a sterile hypodermic needle.

The creation and early implementation of a high speed fiber optic network for a university health sciences center.

In late 1989 the University of Missouri Health Sciences Center began the process of creating an extensive fiber optic network throughout its facilities, with the intent to provide networked computer access to anyone in the Center desiring such access, regardless of geographic location or organizational affiliation. A committee representing all disciplines within the Center produced and, in conjunction with independent consultants, approved a comprehensive design for the network. Installation of network backbone components commenced in the second half of 1990 and was completed in early 1991. As the network entered its initial phases of operation, the first realities of this important new resource began to manifest themselves as enhanced functional capacity in the Health Sciences Center. This paper describes the development of the network, with emphasis on its design criteria, installation, early operation, and management. Also included are discussions on its organizational impact and its evolving significance as a medical community resource.

Pesticide personal protective clothing.

A fairly large established data base provides information on clothing worn by U.S. and Canadian farmers to work with pesticides, their attitudes and beliefs about pesticide risk, and clothing as a dermal barrier. Very limited similar data are available for farmers in less developed countries. Clearly, farmers perceive the benefits of pesticides to far exceed any risks. While few report poisoning symptoms, most believe that their usual work clothing offers a sufficient pesticide barrier, and few wear special-purpose protective clothing. Gloves of various materials, including cotton and leather, appear to be the major protective clothing item. Although farmers feel that their usual work clothing provides excellent protection, fabric penetration research does not support this. Shirting-weight fabrics offer some limited protection against light spray of field-strenght pesticides. Heavier-weight fabrics, such as denim and twill, are better barriers. With a heavier spray or a spill, usual work clothing does not give sufficient protection. Greater protection can usually be achieved with the use of a fluorocarbon finished fabric, such as Scotchgard or Zepel. Scotchgard can readily be applied at home. A durable-press finish does not appear to improve fabric's pesticide-barrier resistance and some data suggest that it may decrease barrier properties. A second alternative for increased protection is the use of a special-purpose fabric, such as a coated nonwoven or possibly Gore-Tex. Numerous other new "waterproof breathable" fabrics have recently come to the market. Many of these are finished or coated fabrics and one would expect them to be at least somewhat resistant to pesticides. However, they have not been tested. Wearing an additional layer also appears to be another clothing strategy to minimize exposure. Fabric penetration research also shows that pesticide formulation, volume or spray regime, concentration, and active ingredients influence the barrier properties of fabrics. Clothing evaluation studies have shown that protective clothing and coveralls of various materials and designs were effective in reducing exposure. Results of some of these studies suggested that the farmer's typical work clothing was more effective than fabric penetration results suggested. This apparent conflict is not surprising, given the methods used in both types of research. The field studies use pads placed in various areas under the clothing. This method assumes that exposure is uniform over entire body regions. But fluorescent tracer research has shown that this is not a valid assumption (DeJonge et al. 1985; Fenske 1988). Also, the way in which the pads are attached may make a difference, although no research has examined this issue.(ABSTRACT TRUNCATED AT 400 WORDS)

Pesticide decontamination from fabric by laundering and simulated weathering.

This laboratory study investigated the effectiveness of selected detergents and the phenomenon of simulated environmental conditions (weathering) on the removal of a commercial-grade mixture of parathion and methyl parathion from a three-layer laminated fabric. The weathering treatment consisted of exposure and non-exposure to simulated environmental conditions of heat, light, and humidity. Contaminated fabric samples were laundered in one of three detergents containing an anionic, a nonionic, and a combined anionic and nonionic surfactant. The test fabric, a three-layer fabric containing an impermeable microporous film laminated between two layers of nylon, was pipette-contaminated with 400 microliters of field strength pesticide solution and allowed to dry. Half of the contaminated samples were weathered in an Atlas Fade-Ometer. All of the contaminated samples were subsequently laundered in a Launder-Ometer. Percent of pesticide residue was determined by gas chromatography. Weathering did significantly reduce both parathion and methyl parathion residues remaining in the test fabric. No statistically significant difference was found among the three detergents. High amounts of both parathion and methyl parathion remained in the test fabric after weathering and laundry treatments. Before the test fabric can be recommended for use in protective garments further research is needed to develop more effective decontamination procedures.

Expanded polytetrafluoroethylene as a microvascular graft: a study of four fibril lengths.

The utility for a prosthetic microvascular graft is well demonstrated, but previous studies have been inconclusive. Expanded polytetrafluoroethylene (Gore-Tex) has been most widely tested as a prosthetic graft. Polytetrafluoroethylene is composed of transverse nodules connected by long fibrils. This study evaluates the effect of fibril length on observed patency in a 1-mm inner-diameter system. Fibril lengths tested were 30, 60, 90, and 120 micron. One-hundred and sixty-three grafts were implanted in the abdominal aorta of Sprague-Dawley rats by a single surgeon using a standardized technique. No anticoagulants were used. Grafts were harvested at predetermined times and evaluated macroscopically, by scanning electron microscope, and by standard histology. The highest patency observed was 97.7 percent in the 90-micron fibril-length grafts. Fibril morphology also affected patency. Increased patency was associated with an amorphous fibril pattern. The graft functioned as a matrix for the formation of a pseudoartery, complete with monocell-thick intima and smooth-muscle media. A foreign-body reaction was observed in the 60-micron fibril-length graft only. Expanded polytetrafluoroethylene does show promise as a microvascular graft. Both fibril length and morphology affect observed patency.