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The highly conserved protein kinase TOR and its signaling network controls cell growth in response to nutrients, growth factors, and other environmental conditions [23]. The corresponding author noted that Sml1 degradation in response to DNA damage is a well-known phenomenon and following consultation with a PLOS ONE Editorial Board Member, this issue is considered resolved. The corresponding author stated that the original, uncropped images underlying this article [1] are partly available for Figs 1, 3, 4 and 5, and that the individual-level quantitative data underlying this article [1] are available for Figs 1A, 1C and 4A.

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The nanocomposites of polythiourethane (PTU) with Fe.sub.3O.sub.4 were fabricated via an isocyanate-free approach. The nanocomposites simultaneously had the reprocessing, shape memory and photothermal properties. First, a linear PTU carrying a plethora of thiol groups was synthesized via the ring opening polyaddition between a bicyclic trithiocarbonate and a poly (propylene oxide) diamine. In the meantime, the surfaces of Fe.sub.3O.sub.4 nanoparticles were functionalized with thiol groups. Second, the co-crosslinking between the linear PTU and the thiol-functionalized Fe.sub.3O.sub.4 was performed via the coupling of thiol radicals with a radical initiator. Notably, the nanocomposites of PTU with Fe.sub.3O.sub.4 were successfully obtained with the fine dispersion of Fe.sub.3O.sub.4 nanoparticle in PTU matrix. Compared to control PTU, the nanocomposites displayed the improved thermomechanical properties. More importantly, the nanocomposites had reprocessing properties. The dynamic exchange of disulfide bonds is responsible for the reprocessing behavior. Owing to the crosslinking with disulfide bonds, PTU had shape memory properties. Notably, the incorporation of Fe.sub.3O.sub.4 nanoparticles was capable of improving the shape memory properties. In addition, the nanocomposites displayed the photothermal properties with the incorporation of Fe.sub.3O.sub.4 nanoparticles. The photothermal conversion behavior can be utilized to trigger the shape recovery of the nanocomposites under near-infrared light irradiation and in a non-contact fashion.

A nanocomposite consisting of bimetallic AuPd nanoparticles, which were modified with CeO.sub.2 (AuPd@CeO.sub.2), and deposited on potassium titanate nanobelts (KTN) as support, is shown to exhibit outstanding catalytic performance in the selective catalytic reduction of NO with CO. Transmission electron microscopy and energy dispersive X-Ray elemental mapping indicated that the AuPd nanoparticles surrounded by CeO.sub.2 were well-mixed forming an alloy. The potassium titanate support consisted of 1-3 [micro]m long and 8-14 nm wide nanobelts. The AuPd@CeO.sub.2/KTN catalyst showed full NO conversion at 100 % selectivity to N.sub.2 at a gas-hourly space velocity (GHSV) of 15,000 h.sup.-1 and 200 °C. The outstanding performance of the AuPd@CeO.sub.2/KNT catalyst is attributed to favorable synergies between its components. Corresponding monometallic Au catalysts supported on KTN (Au@CeO.sub.2/KNT), as well as bimetallic AuPd supported on TiO.sub.2 (AuPd@CeO.sub.2/TiO.sub.2), showed inferior catalytic performance, indicating the absence of a beneficial synergy between the different components. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) combined with modulation excitation spectroscopy (MES) proved that alloying of Au with Pd enhances the ability to adsorb CO and NO on the surface in an on-top configuration and that the deposition of the bimetallic AuPd nanoparticles on KTN facilitates the crucial formation of isocyanate (-NCO) species, resulting in high conversion and selectivity.

The isocyanate monomer 1,6-hexamethylene diisocyanate (HDI) and one of its trimers, HDI isocyanurate, are airway and skin sensitizers contained in polyurethane paint. The toxic response of cultured skin cells to these compounds was measured by evaluating the isocyanate concentrations at which 50% of the cells die (i.e., lethal concentration 50%, LC 50 ) because the relative toxicity of each form of HDI should be considered when exposure limits of HDI-based paints are set. By using a luminescent ATP-viability assay, we compared the cytotoxic effects of HDI monomer and HDI isocyanurate on cultured human skin cells (keratinocytes, fibroblasts, and melanocytes) after 4-h isocyanate exposures using culture media with varying levels of nutrients in order to also determine the effects of media composition on isocyanate toxicity. Before analysis, experimental wells were normalized to controls containing cells that were cultured with the same vehicle and media. The measured mean LC 50 values ranged from 5 to 200 µM across the experimental conditions, in which HDI isocyanurate in protein-devoid media was the most toxic to cells, producing the lowest LC 50 values. For HDI monomer, keratinocytes were the most resistant to its toxicity and melanocytes were the most susceptible. However, when exposed to HDI isocyanurate, the opposite was observed, with melanocytes being the most resilient and the keratinocytes and fibroblasts were more susceptible. Depending on the type of skin cells, dose–response data indicated that HDI isocyanurate was 2–6 times more toxic than HDI monomer when using protein-devoid media whereas HDI isocyanurate was 4–13 times more toxic than HDI monomer when protein-rich media was used. Therefore, if the protein-devoid saline medium alone were used for these experiments, then a significant under-estimation of their relative toxicities in protein-rich environments would have resulted. This difference is because HDI monomer toxicity was more attenuated by the presence of protein in the culture media than HDI isocyanurate toxicity. Thus, conclusions based on comparative toxicity studies and consequent inference applied to potential human toxicity can be affected by in vitro culture media conditions. The physiochemical difference in reactivity of the two forms of HDI to biological molecules most likely explains the observed toxicity differences and may have implications for skin penetration, adverse effects like skin sensitization, and systemic responses like asthma. Future studies are warranted to investigate differences in the biological availability, cellular toxicity, and immunologic sensitization mechanisms for HDI monomer and HDI isocyanurate.

4,4′-Methylenediphenyldiisocyanate (MDI), toluenediisocyanate (2,4-TDI and 2,6-TDI), and 1,6′-hexamethylenediisocyanate (HDI) are all commonly used in the production of polyurethane-containing materials in different application areas. Workers exposed occupationally to these compounds may develop sensitization with the potential to lead to asthma. Isocyanates are metabolized in vivo by conjugation to macromolecules and/or by acetylation prior to being eliminated in urine. The hydrolysis of urine samples releases free amine compounds from these metabolites as biomarkers of exposure, specific to each parent isocyanate: 4,4′-methylenedianiline (MDA), toluenediamine (2,4-TDA and 2,6-TDA), and hexamethylenediamine (HDA). To address the need for a validated method that could be used for the simultaneous determination of biomarkers of aliphatic and aromatic isocyanates to monitor occupational exposure based on recommended thresholds, we have developed an UPLC-MS/MS method for the quantitation of MDA, TDA isomers, and HDA following acid hydrolysis, solid-phase extraction, and derivatization of urine samples. Free amine compounds were derivatized with acetic anhydride to augment chromatographic retention and signal intensity. The method was developed considering the biological guidance value (BGV) of MDA at 10 μg L−1, and biological exposure indices (BEI) of TDA isomers and HDA at 5 μg g−1 and 15 μg g−1 creatinine, respectively. Limits of detection allowed monitoring down to 6% of BGV/BEI, with precision within 8%. The accuracy and reliability of the method were assessed using inter-laboratory reference samples and deemed acceptable based on three rounds of measurements. This novel method has therefore been proven as useful for occupational safety and health assessments.

Green and sustainable cellulose-based hydrophobic coatings are increasingly the subject of scientific and industrial research. However, few researchers pay attention to preparing it by a one-step method. Therefore, a superhydrophobic coating composed of hydrophobic SiO[sub.2] and cellulose nanofiber modified by 3,4-dichlorophenyl isocyanate was manufactured through one-step ball milling. It was found that the ball milling can promote SiO[sub.2] dispersion and achieve the preparation of modified nanocellulose, which further disperse SiO[sub.2] nanoparticles to form film or coating. Compared with the ultrasonic dispersion method, the composite coating prepared by ball milling method can obtain higher water contact angle and more stable hydrophobic properties. The hydrophobic cellulose nanofiber can load 1.5 equivalents of SiO[sub.2] nanoparticles to form a uniform film with the water contact angle of 158.0° and low moisture absorption. When this nanocomposite is used as a coating material, it can impart super-hydrophobicity to paper surface with water contact angle of 155.8°. This work provides a facile way to prepare superhydrophobic nanocellulose/nanoparticles composite coatings and films, thereby broadening the ways of dispersing nanoparticles and constructing superhydrophobic coatings.

In this paper, the effects of HTPBs with different main-chain microstructures on their triblock copolymers and polyurethane properties were investigated. Three polyether-modified HTPB triblock copolymers were successfully synthesized via a cationic ring-opening copolymerization reaction using three HTPBs with different microstructures prepared via three different polymerization methods as the macromolecular chain transfer agents and tetrahydrofuran (THF) and propylene oxide (PO) as the copolymerization monomers. Finally, the corresponding polyurethane elastomers were prepared using the three triblock copolymers as soft segments and toluene diisocyanate (TDI) as hard segments. The results of an analysis of the triblock copolymers showed that the triblock copolymers had lower viscosity and glass transition temperature (Tg) values as the HTPB 1,2 structure content decreased, although the effect on the thermal decomposition temperature was not significant. An analysis of the polyurethane elastomers revealed that as the content of the 1,2 structure in HTPB increased, its corresponding polyurethane elastomers showed a gradual increase in breaking strength and a gradual decrease in elongation at break. In addition, PU-1 had stronger crystallization properties compared to PU-2 and PU-3. However, the differences in the microstructures of the HTPBs did not seem to have much effect on the surface properties of the polyurethane elastomers.

Most of the individual and/or amalgamated compounds present in the atmospheric air are not known for their toxicologic potential and impact on human health. The toxicologic strength of methyl isocyanate (MIC) gas was unknown till its accidental leakage that instantly claimed thousands of lives. Cytogenetic study showed increased chromosome aberrations (CA) and sister chromatid exchanges (SCEs) and delayed cell replication index (RI) in a multicentre genetic screening program on gas victims immediate post-disaster. A surveillance study after 30 years displayed reduction in CA compared to the initial status in survivors of the severely and moderately exposed strata. Altogether, cytogenetic damage was significantly predominant in the severely exposed population. Stable and replicable aberrations and chromatid exchanges were detected in both studies, which collectively indicate genetic instability. The variation in individual cytogenetic spectrum from similar exposure status could be the result of inter-individual response to the external factors over 30 years post-disaster. The spectrum of CA detected after 30 years might be the cumulative effect of occupational, environmental and life-style factors at a background of one episode of acute MIC exposure. Had MIC’s toxicologic potential was known before, fatality and health effects could have been averted. In vitro assessment of toxicity of tin showed a positive correlation with dose and age of exposure, which was aggravated by smoking. Age has shown a significant effect on CA in the general population. The present report recommends evaluation of toxicity prior to use, and reduction of pollution at source for a maintaining a sustainable environmental context.