Publications by authors named "Siebert L"

Purpose: The purpose of this laboratory study was to evaluate common materials for isolation and neutralizing agents for hydrofluoric acid (HF). Additionally, surfaces of lithium disilicate ceramic were examined for precipitates after the etching and neutralizing process.

Materials And Methods: The HF permeability of the following isolation agents (n=8) was investigated by positioning them over pH indicator paper under airtight conditions and applying 9% HF: latex rubber dam; elastic plastomer rubber dam; nitrile gloves; latex gloves; liquid rubber dam; Teflon; AZ strip.

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Article Synopsis
  • * The authors developed a new, budget-friendly material system using sodium alginate hydrogel and coconut fat that allows for accurate adjustment of imaging properties for CT and ultrasound independently.
  • * This innovative approach is particularly advantageous in low-resource settings, as the materials are affordable (less than $1 USD/kg) and easily accessible, enabling the creation of versatile phantoms to improve surgical training and patient care.
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Zinc oxide (ZnO) is considered to be one of the most explored and reliable sensing materials for UV detection due to its excellent properties, like a wide band gap and high exciton energy. Our current study on a photodetector based on tetrapodal ZnO (t-ZnO) reported an extremely high UV response of ~9200 for 394 nm UV illumination at 25 °C. The t-ZnO network structure and morphology were investigated using XRD and SEM.

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Many technological systems these days interact with their environment with increasingly little human intervention. This situation comes with higher stakes and consequences that society needs to manage. No longer are we dealing with 404 pages: AI systems today may cause serious harm.

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Wound treatment requires a plethora of independent properties. Hydration, anti-bacterial properties, oxygenation and patient-specific drug delivery all contribute to the best possible wound healing. Three-dimensional (3D) printing has emerged as a set of techniques to realize individually adapted wound dressings with open porous structure from biomedically optimized materials.

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As the necessary transition to a supply of renewable energy moves forward rapidly, hydrogen (H) becomes increasingly important as a green chemical energy carrier. The manifold applications associated with the use of hydrogen in the energy sector require sensor materials that can efficiently detect H in small quantities and in gas mixtures. As a possible candidate, we here present a metal-organic framework (MOF, namely ZIF-8) functionalized metal-oxide gas sensor (MOS, namely ZnO).

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Batteries play a critical role in achieving zero-emission goals and in the transition toward a more circular economy. Ensuring battery safety is a top priority for manufacturers and consumers alike, and hence is an active topic of research. Metal-oxide nanostructures have unique properties that make them highly promising for gas sensing in battery safety applications.

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Objectives: The aim of this study was to evaluate the mechanical properties and cost efficiency of direct ink writing (DIW) printing of two different zirconia inks compared to casting and subtractive manufacturing.

Methods: Zirconia disks were manufactured by DIW printing and the casting process and divided into six subgroups (n = 20) according to sintering temperatures (1350 °C, 1450 °C and 1550 °C) and two different ink compositions (Ink 1, Ink 2). A CAD/CAM-milled high strength zirconia (3Y-TZP) was added as reference group.

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Zinc oxide (ZnO) tetrapods as microparticles with nanostructured surfaces show peculiar physical properties and anti-infective activities. The aim of this study was to investigate the antibacterial and bactericidal properties of ZnO tetrapods in comparison to spherical, unstructured ZnO particles. Additionally, killing rates of either methylene blue-treated or untreated tetrapods and spherical ZnO particles for Gram-negative and Gram-positive bacteria species were determined.

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Neurodegenerative diseases such as Parkinson's (PD) and Alzheimer's disease (AD), the prevalence of which is rapidly rising due to an aging world population and westernization of lifestyles, are expected to put a strong socioeconomic burden on health systems worldwide. Clinical trials of therapies against PD and AD have only shown limited success so far. Therefore, research has extended its scope to a systems medicine point of view, with a particular focus on the gastrointestinal-brain axis as a potential main actor in disease development and progression.

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People seem to hold the human driver to be primarily responsible when their partially automated vehicle crashes, yet is this reasonable? While the driver is often required to immediately take over from the automation when it fails, placing such high expectations on the driver to remain vigilant in partially automated driving is unreasonable. Drivers show difficulties in taking over control when needed immediately, potentially resulting in dangerous situations. From a normative perspective, it would be reasonable to consider the impact of automation on the driver's ability to take over control when attributing responsibility for a crash.

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Resistive Field Grading Materials (RFGM) are used in critical regions in the electrical insulation system of high-voltage direct-current cable systems. Here, we describe a novel type of RFGM, based on a percolated network of zinc oxide (ZnO) tetrapods in a rubber matrix. The electrical conductivity of the composite increases by a factor of 10 for electric fields > 1 kV mm, as a result of the highly anisotropic shape of the tetrapods and their significant bandgap (3.

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Unlabelled: The pursuit of values drives human behavior and promotes cooperation. Existing research is focused on general values (e.g.

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The aim of this study was to examine the interaction between the oculomotory system and the stomatognathic system based on morphofunctional relationships between the corresponding cranial nerves, their core areas and the reticular formation as a "link" by means of optometric examinations. Test subjects (N = 100) were prospectively recruited and divided into two groups: a young-age (N = 53, age 6-16 years) and old-age group (N = 47, 23-78 years). We determined the horizontal range of convergence and divergence as well as the near convergence point.

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Advanced wound scaffolds that integrate active substances to treat chronic wounds have gained significant recent attention. While wound scaffolds and advanced functionalities have previously been incorporated into one medical device, the wirelessly triggered release of active substances has remained the focus of many research endeavors. To combine multiple functions including light-triggered activation, anti-septic, angiogenic, and moisturizing properties, we have developed a 3D printed hydrogel patch encapsulating vascular endothelial growth factor (VEGF) decorated with photoactive and antibacterial tetrapodal zinc oxide (t-ZnO) microparticles.

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Prior research largely has explored judicial perceptions of risk assessment in sentencing. Little is known about how other court actors, specifically, prosecutors and defense attorneys, perceive risk assessments in the sentencing process. Here, we report a qualitative study on the use of risk assessment by prosecutors and defense attorneys in Virginia.

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Laser diodes are efficient light sources. However, state-of-the-art laser diode-based lighting systems rely on light-converting inorganic phosphor materials, which strongly limit the efficiency and lifetime, as well as achievable light output due to energy losses, saturation, thermal degradation, and low irradiance levels. Here, we demonstrate a macroscopically expanded, three-dimensional diffuser composed of interconnected hollow hexagonal boron nitride microtubes with nanoscopic wall-thickness, acting as an artificial solid fog, capable of withstanding ~10 times the irradiance level of remote phosphors.

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In this work, the one-step three-dimensional (3D) printing of 20 nm nanowire (NW)-covered CuO/CuO/Cu microparticles (MPs) with diameters of 15-25 μm on the surface of the glass substrate forming an ordered net is successfully reported for the first time. 3D-printed Cu MP-based stripes formed nonplanar CuO/CuO/Cu heterojunctions after thermal annealing at 425 °C for 2 h in air and were fully covered with a 20 nm NW net bridging MPs with external Au contacts. The morphological, vibrational, chemical, and structural investigations were performed in detail, showing the high crystallinity of the NWs and 3D-printed CuO/CuO/Cu heterojunction lines, as well as the growth of CuO NWs on the surface of MPs.

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Virginia's sentencing guidelines include alternative sanctions based on the use of a quantitative instrument called the Nonviolent Risk Assessment (NVRA) that identifies individuals convicted of drug and property crimes that are considered to be at lower risk of recidivism. Although nondispositive, the NVRA affords judges the discretion to grant alternative sentences to eligible low-risk defendants. In this study, we explore how judges make use of the NVRA instrument when sentencing individuals convicted of low-level drug and property crimes.

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Porous hydrogel scaffolds are ideal candidates for mimicking cellular microenvironments, regarding both structural and mechanical aspects. We present a novel strategy to use uniquely designed ceramic networks as templates for generating hydrogels with a network of interconnected pores in the form of microchannels. The advantages of this new approach are the high and guaranteed interconnectivity of the microchannels, as well as the possibility to produce channels with diameters smaller than 7 μm.

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Mastitis is a detrimental disease in the dairy industry that decreases milk quality and costs upwards of $2 billion annually. Often, mastitis results from bacteria entering the gland through the teat opening. Streptococcus uberis is responsible for a high percentage of subclinical and clinical mastitis.

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Buckminster fullerene (C60) based hybrid metal oxide materials are receiving considerable attention because of their excellent fundamental and applied aspects, like semiconducting, electron transfer, luminescent behaviors, etc. and this work briefly discusses the successful fabrication of C60 decorated ZnO tetrapod materials and their detailed structure-property relationships including device sensing applications. The electron microscopy investigations indicate that a quite dense surface coverage of ZnO tetrapods with C60 clusters is achieved.

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Fetal alcohol spectrum disorders (FASD) describe neurodevelopmental deficits in children exposed to alcohol in utero. We hypothesized that gestational alcohol significantly alters fetal brain regional protein signature. Pregnant rats were binge-treated with alcohol or pair-fed and nutritionally-controlled.

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