Lausensantos9382

For scenarios such as conversion and conservation, reference levels of biota exposure for some species of representative organisms can be exceeded.Tissue engineering has attracted attention worldwide because of its application in regenerative medicine, drug screening, and cultured meat. Numerous biofabrication techniques for producing tissues have been developed, including various scaffold and printing methods. Here, we have proposed a novel tissue engineering method using a net metal mould without the use of a scaffold. Briefly, normal human dermal fibroblasts seeded on a dimple plate were subjected to static culture technique for several days to form spheroids. Spheroids of diameter ⩾200μm were poured into a net-shaped mould of gap ⩽100μm and subjected to shake-cultivation for several weeks, facilitating their fusion to form a three-dimensional (3D) tissue. Through this study, we successfully constructed a scaffold-free 3D tissue having strength that can be easily manipulated, which was difficult to construct using conventional tissue engineering methods. We also investigated the viability of the 3D tissue and found that the condition of the tissues was completely different depending on the culture media used. Collectively, this method allows scaffold-free culture of 3D tissues of unprecedented thickness, and may contribute largely to next-generation tissue engineering products.Silver has been considered as one of the simple one-phase materials that do not exhibit high pressure or high temperature polymorphism. The solid phase of Ag at ambient conditions is face-centered cubic (fcc) one. However, very recently another solid phase of silver, body-centered cubic (bcc) one, was detected in shock-wave (SW) experiments, and a more sophisticated phase diagram of Ag with the two solid phases was published by Smirnov. In this work, using a suite ofab initioquantum molecular dynamics (QMD) simulations based on the Z methodology which combines both direct Z method for the simulation of melting curves and inverse Z method for the calculation of solid-solid phase boundaries, we refine the phase diagram of Smirnov. We calculate the melting curves of both fcc-Ag and bcc-Ag and obtain an equation for the fcc-bcc solid-solid phase transition boundary. We also obtain the thermal equation of state of Ag which is in agreement with experimental data and QMD simulations. We argue that, despite being a polymorphic rather than a simple one-phase material, silver can be considered as an SW standard.Aflatoxin is regarded as the potent carcinogenic agent which is secreted from fungi and present in some food products. So far, many detection methods have been developed to determine the trace amounts of aflatoxin in foods. In the present study a colorimetric competitive assay for detection of aflatoxin B1 (AFB1) has been developed based on interaction of gelatin functionalized gold nanoparticles (AuNPs@gelatin) in specific enzymatic reaction. Bacterial supernatant containing gelatinase enzyme were used as the substrate that could digest the coated gelatin on the surface of AuNPs and following in the presence of NaCl medium ingredient resulted to color change of AuNPs colloidal solution from red to purple. It was observed that with addition of aflatoxin to the bacterial supernatant, aflatoxin could interfere in aggregation of AuNPs and inhibited the process which subsequently prevent the expected color change induced by AuNPs aggregation. The supernatant containing AuNPs were investigated to analyze their induced surface plasmon resonance spectra through UV-visible spectroscopy. The absorption values were directly proportional with the applied AFB1 concentration. The experiment conditions including incubation time, AuNPs concentration and pH were investigated. The obtained results showed that through this approach we could detect the AFB1 in a linear range from 10 to 140 pg ml-1, with detection limit of 4 pg ml-1. Real sample assay in saffron samples showed recoveries percentage of 92.4%-95.3%. The applied approach proposed simple, cost effective and specific method for detection of AFB1 toxin in food samples.High frequency electrical stimulation of brain is commonly used in research experiments and clinical trials as a modern tool for control of epileptic seizures. However, the mechanistic basis by which periodic external stimuli alter the brain state is not well understood. This study provides a computational insight into the mechanism of seizure suppression by high frequency stimulation (HFS). In particular, a modified version of the Jansen-Rit neural mass model is employed, in which EEG signals can be considered as the input. The proposed model reproduces seizure-like activity in the output during the ictal period of the input signal. By applying a control signal to the model, a wide range of stimulation amplitudes and frequencies are systematically explored. Simulation results reveal that HFS can effectively suppress the seizure-like activity. Our results suggest that HFS has the ability of shifting the operating state of neural populations away from a critical condition. Furthermore, a closed-loop control strategy is proposed in this paper. The main objective has been to considerably reduce the control effort needed for blocking abnormal activity of the brain. Such an energy reduction could be of practical importance, to reduce possible side effects and increase battery life for implanted neurostimulators.Objectives.To optimize the absorbed organ dose in relation to the field of view for temporomandibular joint examinations in four cone beam computed tomography devices.Methods.An anthropomorphic adult head and neck phantom, and 192 LiF dosimeters (TLD-100) were used. The dosimeters were placed in the region corresponding to the lens, parotid glands, submandibular glands, and thyroid. Small, medium and large FOVs were selected on Orthopantomograph OP300 Maxio, PaX-i3D Smart, ORTHOPHOS XG, and i-CAT Next Generation device when it was possible.Results.A wide range of absorbed dose values was recorded for all organs due to the different exposure parameters of each device. The radiosensitive organ with the highest dose was the parotid glands. The devices with 5 × 5 cm FOV recorded a lower dose in this protocol, while for the device without a small FOV (≤5 × 5 cm), the lowest dose was observed with the large FOV (6 × 16 cm).Conclusions.We recommend a double exposure with an FOV of 5 × 5 cm in the OP300 Maxio, PaX-i3D Smart, and ORTHOPHOS XG device, while in the i-CAT Next Generation device, a single exposure FOV of 6 × 16 cm is indicated.After nuclear accidents, people can be contaminated internally via ingestion, inhalation and via intact skin or wounds. The assessment of absorbed, committed doses after internal exposure is based on activity measurement by in vivo or in vitro bioassay. Estimation of dose following internal contamination is dependent on understanding the nature and form of the radionuclide. Direct counting methods that directly measure γ-rays coming from within the body or bioassay methods that measure the amount of radioactive materials in urine or feces are used to estimate the intake, which is required for calculating internal exposure doses. The interpretation of these data in terms of intake and the lifetime committed dose requires knowledge or making assumptions about a number of parameters (time, type of exposure, route of the exposure, physical, biological and chemical characteristics) and their biokinetics inside the body. Radioactive materials incorporated into the body emit radiation within the body. Accumulation in some specific organs may occur depending on the types of radioactive materials. Decorporation therapy is that acceleration of the natural rate of elimination of the contaminant will reduce the amount of radioactivity retained in the body. This article presents an overview of treatment of radiological contamination after internal contamination.Positron Emission Tomography (PET) reconstructed image signal-to-noise ratio (SNR) can be improved by including the 511 keV photon pair coincidence time-of-flight (TOF) information. The degree of SNR improvement from this TOF capability depends on the coincidence time resolution (CTR) of the PET system, which is essentially the variation in photon arrival time differences over all coincident photon pairs detected for a point positron source placed at the system center. The CTR is determined by several factors including the intrinsic properties of the scintillation crystals and photodetectors, crystal-to-photodetector coupling configurations, reflective materials, and the electronic readout configuration scheme. The goal of the present work is to build a novel TOF-PET system with 100 picoseconds (ps) CTR, which provides an additional factor of 1.5-2.0 improvement in reconstructed image SNR compared to state-of-the-art TOF-PET systems which achieve 225-400 ps CTR. A critical parameter to understand is the opticpaint treatments, respectively.The current study concerns development of fullerene-C60-encapsulated TiO2nanoparticles hybrid for an efficient detection of volatile organic compounds (VOCs). The nanocomposite was synthesized via chemical route by using hydrated fullerene-C60and sol-gel derived undopedp-type TiO2nanoparticles. The nanocomposite was characterized morphologically and structurally comparing with pure C60clusters and pure TiO2nanoparticles as the reference materials. The average diameter of the C60-encapsulated TiO2nanoparticles was 150 nm whereas the average diameters of C60clusters and pure TiO2nanoparticles were 161 nm and 18 nm respectively. Therefore, all the materials were implemented in interdigitated electrode based planner structured sensors and tested towards multiple VOCs. However, C60-TiO2composite exhibited its natural selectivity towards formaldehyde with a very high sensitivity for the concentration range of 1-1000 ppm. C60-encapsulated TiO2nanoparticles depicted more than double response magnitude (117%) than the pure TiO2nanoparticle (48%) and pure C60particles (40%) and appreciably fast response/recovery (12 s/331 s) towards 100 ppm of formaldehyde at 150 °C. However, the efficient VOC sensing was achieved in C60-encapsulated TiO2sensors possibly due to the extreme reactive surface provided by the oxygen functionalized C60and easy electronic exchange between ambient and the TiO2nanoparticles through C60layers. The combined properties of both C60and TiO2lead to the formation of a promising nanocomposite which provided better sensing characteristics than that of the pure materials.The threat of a large-scale radiological or nuclear (R/N) incident looms in the present-day climate, as noted most recently in an editorial in Scientific American (March 2021). find more These large-scale incidents are infrequent but affect large numbers of people. Smaller-scale R/N incidents occur more often, affecting smaller numbers of people. There is more awareness of acute radiation syndrome (ARS) in the medical community; however, ionizing radiation-induced injuries to the skin are much less understood. This article will provide an overview of radiation-induced injuries to the skin, deeper tissues, and organs. The history and nomenclature; types and causes of injuries; pathophysiology; evaluation and diagnosis; current medical management; and current research of the evaluation and management are presented. Cutaneous radiation injuries (CRI) or local radiation injuries (LRI) may lead to cutaneous radiation syndrome (CRS), a sub-syndrome of ARS. These injuries may occur from exposure to radioactive particles suspended in the environment (air, soil, water) after a nuclear detonation (ND), an improvised nuclear detonation (IND), a nuclear power plant (NPP) incident, or an encounter with a radioactive dispersal or exposure device (RDD/RED).