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In this study, we report the rejuvenation of aged muscle fibers facilitated by heterochronic parabiosis, underscored by a notable upregulation in peroxisomal gene expression. Our findings highlight the pivotal role of dysregulation in peroxisomal biogenesis and consequential impairment of fatty acid β-oxidation in myoblast differentiation and muscle regeneration. Notably, we demonstrate the novel therapeutic strategy that involves the administration of peroxisome-COS-FITC complexes and nanozymes that mimic peroxisomal function, effectively rejuvenating aged muscle tissues. This innovative approach paves the way for new methods to mitigate or reverse sarcopenia, offering new avenues of the treatment of age-related muscle atrophy and a significant advancement in our understanding for the molecular underpinnings in muscle aging. [Display omitted] • Peroxisome dysfunction linked to sarcopenia and muscle degeneration. • Innovative peroxisomal transplant therapy rejuvenates aged muscles. • Nanozyme technology mimics peroxisomal β-oxidation for muscle health. • Interplay between peroxisomes and mitochondria restores muscle function. [ABSTRACT FROM AUTHOR]

To evaluate the effects of diabetes and corticosteroid injected in the joints on the shoulder motion, gait, and joint capsular properties in a rat stiffness model. A total of 27 rats were randomly distributed into 3 groups—nondiabetes group (group A), diabetes group (group B), and diabetes plus steroid injection group (group C). The diabetes model was developed by inducing hyperglycemia with a submaximal dose of streptozotocin and the stiffness model by completely immobilizing the right shoulder of each animal in all groups with sutures passed between the scapula and humeral shaft. The left shoulder was used as an untreated control in all groups. Three weeks after immobilization, the sutures were removed in all groups, and a single dose of triamcinolone acetonide (0.5 mg/kg) was injected into the glenohumeral joint in group C. After 3 weeks of free activity, range of motion (ROM) evaluation, gait analysis by stride length, and capsular area measurement were performed in all rats. Hyperglycemia was successfully induced with a mean blood glucose level of 448.9±55.9 mg/dL in group B and 431.6±17.8 mg/dL in group C, which were significantly higher than 136.5±13.4 mg/dL in group A (P <.001). A significantly smaller ROM and stride length were found in the right (stiffness-induced) shoulder than that in the left (control) shoulder only in group B, and significantly larger capsular area in the right shoulder than that in the left shoulder in groups A and B (all P <.05). However, in group C, there were no differences between the right and left shoulders in all measurements (all P >.05). In case of the right shoulders in each group, group C showed significantly larger ROM (68° ± 11° vs. 42° ± 7°) and smaller capsular area (3934.4 ± 537.1 pixels vs. 7402.3 ± 1840.3 pixels) than group B (all P <.0167). The diabetic model had a detrimental effect on the development of stiffness by thickening the joint capsule, and an intra-articular steroid injection resolved the thickened joint capsule and restored shoulder motion. [ABSTRACT FROM AUTHOR]

Fatty infiltration (FI) is a key prognostic factor that affects outcomes after rotator cuff repair and is radiologically evaluated using the Goutallier classification. The purpose of this study was to assess alterations in gene and protein expression according to the Goutallier classification in the supraspinatus muscle and any relationships among various gene expression profiles. Twenty-four samples of the supraspinatus muscle from 12 patients with a high FI grade (grade 3 or 4) and 12 patients with a low FI grade (grade 1 or 2) with medium-sized tears were acquired during arthroscopic surgery. Alterations in the expression of genes and proteins associated with adipogenesis, fibrosis, inflammation, and muscle atrophy were compared between the high- and low-FI groups using reverse-transcription quantitative polymerase chain reaction, Western blotting, and immunohistochemistry. mRNA expression of not only the adipogenic genes (peroxisome proliferator–activated receptor γ and CCAAT/enhancer-binding protein α; P <.001 and P =.020) but also the fibrosis-related gene (α-smooth muscle actin; P <.001), inflammation-related genes (interleukin [IL]-1β and tumor necrosis factor α; P =.041 and P =.039), and muscle atrophy–related genes (atrogin 1 and myostatin; P =.006 and P <.001) was higher in the high-FI group compared with that in the low-FI group. In addition, adipogenic gene expression was significantly correlated with the expression of other categories of genes (all P <.05, except atrogin 1). A correlation of gene and protein expression was observed for IL-1β (P =.027) and myostatin (P =.029). The radiologic grading of FI was associated with the expression of various genes, including adipogenic, fibrotic, inflammatory, and atrophy-related genes, and these genes were closely correlated with each other in terms of expression. This information could be helpful in patient counseling. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the altered gene and protein expression patterns in the rotator cuff muscles of smokers and non-smokers with rotator cuff tears and to identify the smoking-associated key genetic factor(s) involved in rotator cuff muscle physiology.Methods: Twenty-four samples of rotator cuff muscle from 12 current heavy smokers (mean age 61.8 ± 5.1 years) and age- and sex-matched 12 non-smokers (mean age 61.8 ± 6.9 years) with medium-sized tears were acquired during arthroscopic surgery. As a statistical method, the propensity score matching technique was used to select control group by 1:1 matching for age and sex. Inclusion criteria were patients who underwent arthroscopic repair for medium-sized full-thickness rotator cuff tears and those that were current smokers with a smoking history >20 packs/year. Patients lacking medium-sized tears, those with recent steroid injection history, isolated subscapularis tear, preoperative stiff shoulder, acute traumatic tear, or previous surgery on the same shoulder, or those that declined to participate were excluded. Alterations in the expression of genes and proteins associated with myogenesis, inflammation, adipogenesis, and muscle fibrosis were compared between smokers and non-smokers with reverse-transcription quantitative polymerase chain reaction, western blotting, and immunohistochemistry.Results: Histologic analysis revealed increased inflammation and remarkable fat accumulation and fibrogenesis in the rotator cuff muscle from smokers compared with that from non-smokers. The mRNA expression levels of inflammatory high mobility group box 1 (HMGB1; P = .043), adipogenic CCAAT/enhancer-binding protein alpha (P = .046) and peroxisome proliferator-activated receptor gamma (PPARγ; P = .048), myogenic differentiation 1 (P = .032), fibrogenic alpha-smooth muscle actin (α-SMA; P = .033), and metalloproteinase 9 (P = .036) were significantly greater in samples from smokers than from non-smokers. A correlation was observed between gene and protein expression of HMGB1 (P = .034), PPARγ (P = .021), and α-SMA (P = .021).Conclusions: Smokers with rotator cuff tears showed high inflammation, large fat infiltration, and fibrosis in rotator cuff muscle that is associated with the increased expression of HMGB1, PPARγ, and α-SMA, respectively.Level Of Evidence: Case control study (Prognostic level III). [ABSTRACT FROM AUTHOR]

Objective: The acoustic characteristics of voice are determined by the source of the sound and shape of the vocal tract. Various anatomical changes after uvulopalatal flap (UPF) operation can change nasalance and/or other voice characteristics. Our aim was to explore the possible effects of UPF creation on speech nasalance and the resonatory features of the final nasal consonants, and thus voice characteristics.Methods: A total of 30 patients (26 males, 4 females) with obstructive sleep apnea who underwent UPF operation were recruited. A Nasometer II 3.4 instrument was used to assess nasalance pre- and post-operatively; the patients read standard Korean passages and the readings were recorded in Computer Speech Laboratory for later spectral analysis. Praat software was used to identify frequency bands affecting perioperative nasalance scores. Minima, maxima, and slopes were analyzed.Results: We found no significant correlation between nasalance scores (any passage) and the respiratory distress index or body mass index. No significant perioperative change in any nasalance score. The moment variations in the final consonants /m/ and /n/ did not change significantly postoperatively. However, the postoperative moment variation of the final consonant /ng/ differed significantly in the third formant (F3) and second bandwidth (BW2).Conclusion: Few significant changes in nasal resonance speech quality were apparent after UPF operation. However, a postoperative acoustic change in the final sound /ng/ may be sustained. Patients may be preoperatively advised that the risk of voice change is very low, but not absent. [ABSTRACT FROM AUTHOR]

We propose an annular core photonic quasi-crystal fiber with ultra-flat dispersion, low confinement loss and small effective mode area covering O, E, S, C, L and U bands. The proposed design has a six-fold symmetric quasiperiodic array of air holes with a central air-hole in the core (an annular core), which induce wideband nearly zero ultra-flattened dispersion of 0 ± 0.11 ps/(nm.km) from 1.15 μm to 1.65 μm, low confinement loss in level of 10 −4 and the small effective mode area of 5.55 μm 2 at 1.55 μm. [ABSTRACT FROM AUTHOR]

A novel photonic crystal fiber design is presented. The design provides broadband high and uniform birefringence, large negative dispersion and low confinement loss. The fiber is based on double-hole assisted core in the conventional square lattice cladding. For the proposed PCF, high and uniform birefringence of 7.5 × 10 −3 , the negative dispersion of −150 ps/(nm km) and an extremely low confinement loss can be obtained over E+ S + C + L + U (1380 ∼ 1780 nm) wavelength bands. [ABSTRACT FROM AUTHOR]

Although various self-healing methods have been suggested until recently, these methods have merits and demerits. The utilization of cementitious material (e.g. expansive agent, mineral admixtures etc.) in various methods may be appropriate due to their good healing efficiency, compatibility with the cement matrix, and low cost, but the efficiency of healing products generated by necessity is not guaranteed. In this study, granulation/surface coating methods are applied to cementitious material. The self-healing time of materials can be controlled via water-soluble film thickness until cracks occur, and healing products will be formed because cementitious material react with moisture via the crack faces after water-soluble film was dissolved by moisture. It was verified through various tests that the granulated cementitious material with water-soluble film coating can control the time of self-healing and can prevent water migration via crack closing. [ABSTRACT FROM AUTHOR]

We carried out a thorough parametric analysis by varying the dimension of the fiber optic Bessel-beam generator (BBG) to obtain the maximum a macroscopic nondiffracting length (NDL). BBG consisted of a single mode fiber (SMF) and serially concatenated coreless silica fiber (CSF), where multimode interference took place to shape the incoming fundamental LP 01 mode to the Bessel-like mode propagating in water. Focusing on three wavelengths λ = 635 nm, 980 nm, and 1550 nm, we used the beam propagation method package for commercially available SMFs for each wavelength to find optimal CSF geometry. We also optimized the SMF parameters to increase the NDL further. Utilizing a simple all-fiber structure, we theoretically predicted that NDL in water reaching ~4 mm could be obtained from a microscopic fiber optic BBG. This result can be readily applied to optical manipulation of biological substances in aqueous solutions and laser material processing and imaging. [ABSTRACT FROM AUTHOR]

Abstract: Various methods are used at the early stages to control setting-time and strength of concrete, when cold-weather concrete is utilized. Among these methods is one that involves the use of an accelerator. Although economical, accelerators have difficulty securing workability because their early hydration makes them react rapidly. Therefore, how to make a tablet for cold-weather concrete, as with the existing medicines and foods, is discussed in this study, including the following items: mortar setting-time, workability by elapsed time, early strength to assure the development of adequate strength, and freezing–thawing resistance. As a result, both the 0.5 and 1.0% tablets were found to be superior. Thus, workability can be secured, as well as the development of early strength to prevent early frost. [Copyright &y& Elsevier]

Abstract: We present an evolutionary algorithm for reconstructing a femtosecond laser pulse from its interferometric autocorrelation trace and laser spectrum. The algorithm is optimized for the intensity and phase characterization of several-cycle optical pulses. We tested this algorithm with numerically-generated femtosecond pulses and then applied it to experimental data. In the experiment, a negatively chirped 31-fs pulse and a sub-10-fs pulse containing high-order phase distortion were characterized. Frequency-resolved optical gating measurements, performed for comparison, confirm the reliability of our technique. [Copyright &y& Elsevier]

The detrimental effects of ultraviolet B (UVB) irradiation have been connected with the enhanced generation of reactive oxygen species (ROS) by UVB. However, the exact source of ROS produced by UVB has not been clearly revealed yet. In this study, we determined the source of ROS production and its role in the UVB-induced activation of nuclear factor (NF)-κB in HaCaT human keratinocytes. UVB irradiation generated ROS in a dose-dependent manner, and this was significantly inhibited by diphenylene iodonium (DPI), apocynin (Apo) and neopterine (Neo), inhibitors of the NADPH oxidase, and indomethacin (Indo), a cyclooxygenase (COX) inhibitor, but not by the mitochondrial electron transport inhibitors and other cytosolic enzyme inhibitors. In addition, these inhibitors of the NADPH oxidase and COX significantly blocked the UVB irradiation-induced nuclear translocation of NF-κB. These results suggest that the NADPH oxidase and COX may be major sources for the UVB-induced ROS generation, and play an essential role in the activation of NF-κB which is involved in the expression of a variety of genes induced by UVB in HaCaT cells. These results further suggest that these enzymes may be good targets for the preventive strategy of UVB-induced skin injury. [Copyright &y& Elsevier]

Recently, certain environmental endocrine disrupters have shown to act as antiandrogens. This suggests that environmental antiandrogens may also be crucial contributors to the increasing incidence of male reproductive abnormalities, requesting the screening and classification of antiandrogenic chemicals. Here, we report the development of a rapid, simple and effective yeast detection system for androgenic and antiandrogenic compounds, which is based on the yeast two-hybrid protein interaction. A yeast strain, ARhLBD-ASC1, was established by co-transformation of yeast cells harboring a lacZ reporter plasmid with two vectors expressing each of LexA fused hinge–ligand binding domain (hLBD) of androgen receptor (AR) and B42 fused ASC-1 that interacts with the AR-hLBD in an androgen-dependent manner. In this yeast strain, androgens, but not other hormones, strongly stimulated the β-galactosidase activity in a dose-dependent manner. The AR antagonists flutamide, cyproterone acetate and spironolactone, and environmental antiandrogens p,p′-DDE and vinclozolin all inhibited the response of the yeast cells to 10 nm testosterone, qualitatively similar to their inhibition reported in mammalian cell systems. Furthermore, the bioassay can be performed with the simple X-gal staining on microtiter plates, suggesting this system as a powerful tool for practical and efficient screening of environmental compounds for their androgenic and antiandrogenic activities. [Copyright &y& Elsevier]

Asiatic acid (AA), a triterpene, decreased viability and induced apoptosis of HepG2 human hepatoma cells in a dose-dependent manner. AA also markedly increased intracellular Ca2+ level, which was blocked by TMB-8 and dantrolene, intracellular Ca2+ release blockers, but not by EGTA, an extracellular Ca2+ chelator. Moreover, AA-induced apoptosis was significantly suppressed by treatment with TMB-8 and dantrolene, suggesting that intracellular Ca2+ release may play an essential role in the AA-induced apoptosis. In addition, AA profoundly increased protein level of p53, which was also inhibited by BAPTA/AM, an intracellular Ca2+ chelator, TMB-8 and dantrolene. Treatment with A23187, a Ca2+ ionophore, or thapsigargin, a Ca2+-ATPase inhibitor, alone enhanced p53 nuclear accumulation, indicating that p53 accumulation is dependent on intracellular Ca2+ increase. Furthermore, the viability of Hep3B, p53-null cells, was much higher than that of HepG2, p53-wild type cells, when treated with AA. Taken together, these results suggest that AA induced apoptosis through increased intracellular Ca2+, which, in turn, enhanced p53 expression in HepG2 cells. These results further suggest that AA may be a valuable agent for the therapeutic intervention of human hepatomas. [Copyright &y& Elsevier]

• Preoxidation effects adsorbing trend of inorganic foulants in the presence of NOM. • 1.5 mg/l of NaOCl at pH 8.5 produce less scaling during CIP. • Optimized NaOCl improves the removal efficiency of Mn and Fe. • Fouling by loosely compaction of skin layer easily remove by backwashing. • Less irreversible fouling produced due to peroxidation. This study investigated the potential for reducing scaling during chemical cleaning of polyvinylidene fluoride membranes by optimizing preoxidation dose and pH. Membranes were fouled by a solution containing inorganic foulants (aluminum, iron, and manganese), humic acid, and kaolin at a Ca+2 strength of 0.5 mM and varying the preoxidation dose. Energy-dispersive spectroscopy was used to verify the presence of inorganic foulants after cleaning. Fourier-transform infrared spectroscopy revealed changes in C Cl and C–F functional groups, with bond vibrations at 542 cm−1 and 1199 cm−1, respectively. Minimum irreversible fouling of 5.4% and maximum flux recovery of 88.8% of the initial value were associated with a preoxidation dose of 1.5 mg/L and pH 8.5. A decrease in amount of aluminum from 5.79 ± 0.021 mg to 3.85 ± 0.054 mg in the presence of humic acid with a removal efficiency greater than 60% was due to alteration of the feed solution, as revealed by mass-balance analysis. Membrane characterization and fouling reversibility analysis confirmed that preoxidation of the feed solution produced less scaling during chemical cleaning. The cake layer fouling contribution was determined by fitting results of Hermia's fouling model analysis, with 1.34–1.85 times lower total fouling indices and 3–5.5 times lower chemically irreversible fouling indices at pH 8.5 and a preoxidation dose of 1.5 mg/L. [ABSTRACT FROM AUTHOR]

This study investigates five different fouling models and contributing factors in membrane-filtration blocking mechanisms in a constant-pressure mode. A polyvinylidene fluoride membrane was used to study the fouling effects of a complex mixture of foulants (a latex-bed suspension, soybean oil, and inorganics) on pristine and chemically cleaned membranes in the presence of humic acid. A significance ratio in linear regression results (p-value) was used to assess the contribution of fouling mechanism in each model. The results indicate that Hermia and Bowen's models correspond closely with the experiment results and confirms that complete blocking is dominant fouling model. We also verify that each developed model is dependent on its experimental conditions. Moreover, the role of complex mixtures, including inorganic foulants, in the fouling process needs to be modified as modified for ceramic membranes and natural organic matter removal in the Wiesner and Kilduff models, respectively. Image 1 • Evaluation of change in membrane fouling behavior after chemical cleaning. • Variation of existing fouling models for complex fouling mixture. • Introduce participation equation for better representation of fouling. • Statistical confirmation of Hermia's model for fouling representation. [ABSTRACT FROM AUTHOR]

The goal of this study was to identify the scaling from the chemical cleaning of a polyvinylidene fluoride (PVDF) membrane, fouled by treating a solution containing inorganic foulants (Al, Fe, and Mn) in the presence of kaolin and humic acid as a natural organic matter at Ca+2 strength of 0.5 mMole. Chemical cleaning of the membrane was conducted using solutions prepared in deionized water and permeate water (PW), and the accumulation of insoluble salts on the membrane during cleaning were evaluated. Energy dispersive spectroscopy analysis was used to verify the presence inorganic foulants, and field emission scanning electron microscopy confirmed the changes in membrane symmetry from the accumulation of the foulants. A Fourier-transformed infrared spectroscopy analysis indicated the presence of new functional groups, i.e., C˗Cl and C˗O with bond vibrations at 542 cm −1 and 1,026 cm−1, respectively, on the membrane surface. The adsorbed mass of HA in the presence of inorganic foulants decreased from 3.54 ± 0.045 mg to 2.24 ± 0.095 mg and 1.71 ± 0.075 mg, and the flux recoveries decreased from 93.2% to 85.69% and 81.92%, for the pristine to chemically DI and PW cleaned membrane, respectively. However, the membrane characterization results confirmed that Al was the major contributor to the accumulation of inorganic salts on the membrane during chemical cleaning and its role was more severe in the presence of Mn. The fitting results of Hermia's fouling models and a specific fouling analysis confirmed the contribution of complete blocking model with increase in irreversible fouling was observed after chemical cleaning. Image 1 • Inorganic foulants adsorbed on membrane in the presence of NOM in water treatment. • Inorganic foulants cause scaling during clean in place (CIP) of membrane. • Sever scaling produced when CIP solution contains inorganic ions. • Al causes more sever scaling problem with trifling role of Mn and Fe. [ABSTRACT FROM AUTHOR]

Summary Obesity-associated metabolic alterations are closely linked to low-grade inflammation in peripheral organs, in which macrophages play a central role. Using genetic labeling of myeloid lineage cells, we show that hypothalamic macrophages normally reside in the perivascular area and circumventricular organ median eminence. Chronic consumption of a high-fat diet (HFD) induces expansion of the monocyte-derived macrophage pool in the hypothalamic arcuate nucleus (ARC), which is significantly attributed to enhanced proliferation of macrophages. Notably, inducible nitric oxide synthase (iNOS) is robustly activated in ARC macrophages of HFD-fed obese mice. Hypothalamic macrophage iNOS inhibition completely abrogates macrophage accumulation and activation, proinflammatory cytokine overproduction, reactive astrogliosis, blood-brain-barrier permeability, and lipid accumulation in the ARC of obese mice. Moreover, central iNOS inhibition improves obesity-induced alterations in systemic glucose metabolism without affecting adiposity. Our findings suggest a critical role for hypothalamic macrophage-expressed iNOS in hypothalamic inflammation and abnormal glucose metabolism in cases of overnutrition-induced obesity. Graphical Abstract Highlights • Chronic exposure to HFD activates and accumulates macrophages in the hypothalamus • HFD increases iNOS expression in the hypothalamic perivascular macrophages • Macrophage iNOS triggers hypothalamic inflammation and vascular hyperpermeability • Inhibition of hypothalamic macrophage iNOS improves glucose metabolism in obese mice Lee et al. demonstrate in mice that, upon prolonged high-fat diet feeding, hypothalamic macrophages proliferate, expand their pool, and sustain hypothalamic inflammation. Moreover, they show that hypothalamic macrophage iNOS inhibition diminishes macrophage activation, astrogliosis, blood-brain-barrier permeability, and impaired glucose metabolism in diet-induced obese mice. [ABSTRACT FROM AUTHOR]

In proton exchange membrane (PEM) water electrolysis, iridium oxide (IrO 2) has often been utilized as a main catalyst for the oxygen evolution reaction (OER) as a rate-determining step. In general, the performance of PEM water electrolysis is dominantly affected by the specific surface area and the porous structure of the IrO 2 catalyst. Thus, in this study, IrO 2 and antimony-doped tin oxide (ATO) nanostructures with high specific surface areas were synthesized through the Adams fusion method. The as-prepared samples showed well-defined porous high-crystalline nanostructures. The ATO nanoparticles as a support were surrounded by IrO 2 nanoparticles as a catalyst without serious agglomeration, indicating that the IrO 2 catalyst was uniformly distributed on the ATO support. Compared to pure IrO 2 , the IrO 2 /ATO mixture electrodes showed superior OER properties because of their increased electrochemical active sites. Image 1 • IrO 2 and ATO nanostructures were synthesized with the Adams fusion method. • The samples showed a well-defined porous high-crystalline nanostructure. • ATO nanoparticles were surrounded by IrO 2 nanoparticles without agglomeration. • IrO 2 /ATO electrodes showed the superior OER properties. • The improved activity results from favorable mass transfer of a reactant of the mesoporous nanostructure. [ABSTRACT FROM AUTHOR]

Purpose: To analyze and compare the gene and protein expression characteristics in torn rotator cuff tendon tissues between diabetic and nondiabetic patients.Methods: This was a pilot study. Twelve samples of rotator cuff tendon tissue from diabetic patients (mean age, 62.3 ± 9.9 years) and 12 age- and sex-matched nondiabetic tendon tissues (62.3 ± 9.9 years) were acquired from the torn tendon end of medium rotator cuff tears during arthroscopic surgery, after applying the same inclusion and exclusion criteria. Expressions of various genes of interest, including collagens I and III, matrix metalloprotease (MMP)-2, MMP-3, MMP-9, MMP-13, interleukin (IL)-1, IL-6, insulin-like growth factor-1, vascular endothelial growth factor, tenomodulin, tumor necrosis factor-α, and p53, were analyzed with real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). In addition, immunohistochemistry and western blot assay were performed for the genes that revealed significantly different expressions in real-time qRT-PCR between groups.Results: Gene expression levels of MMP-9, MMP-13, IL-6, and tenomodulin were significantly higher in the diabetic than in the nondiabetic group by real-time qRT-PCR analyses (P = .011, .004, .009, and .010, respectively). The density of cells expressing MMP-9 and IL-6 was significantly increased in the torn tendons of the diabetic patients on immunohistochemical analysis, and the density of MMP-9 and IL-6 protein expressions was significantly higher in the diabetic group on western blot (P = .018 and .044, respectively).Conclusions: Diabetic torn cuff tendon tissues showed MMP-9 and IL-6 overexpressions compared with controls.Clinical Relevance: The overexpressions of MMP-9 and IL-6 may be one of the explanations for the high healing failure rate after rotator cuff repair in the diabetic patients. [ABSTRACT FROM AUTHOR]

We experimentally demonstrated a tunable microsecond passively Q-switched fiber laser using deionized water (DIW) as a saturable absorber (SA). The DIW-SA was integrated into an all-fiber device by filling the gap between two cleaved fiber facets with DIW, which were enclosed in a glass ferrule. We observed a high nonlinear transmission through DIW-SA and implemented it in an erbium-doped fiber ring laser cavity. Microsecond Q-switched pulse trains were produced tunable from 1564.3 to 1603.4 nm using a fiber-optic Fabry-Perot interference filter within the cavity, avoiding peak water absorption while maintaining stable operation. Tunable and robust Q-switching of a fiber laser using water would open a new avenue of nonlinear aqua-photonics. • The proposed deionized water (DIW) saturable absorber (SA) contains DIW between SMFs to significantly relieve absorption to mitigate the overall cavity loss. In contrast to prior methods, the gap distance between SMFs was reduced by more than 1000 times to obtain a very low insertion loss, enabling wide spectral tunability of a filter. • An all-fiber Fabry-Perot interferometer (FPI) tunable filter was formed by using two cleaved single-mode fibers with a variable air gap. The FPI filter made the Q-switched laser's center wavelength tunable from 1564.3 to 1603.4 nm, covering both C-and L-bands • By integrating the proposed DIW-SA and FPI filter in an Er-doped fiber ring laser cavity, tunable microsecond Q-switched laser pulse trains were successfully generatedachieving the longest lasing wavelength at λ = 1603.4 nm. [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate the impact of thermal and chemical aging processes on high-density polyethylene (HDPE), low-density polyethylene (LDPE), unplasticized polyvinyl chloride (U-PVC), and high-impact polyvinyl chloride (Hi-PVC) pipes. The materials were exposed to 1–10 ppm chemical disinfectants [chlorine dioxide (ClO 2) and hypochlorite (HOCl)] at 40–80 °C for 1200 h. The diffusion properties of the materials were systematically analyzed based on the change in their sorption characteristics and activation energies according to the Arrhenius model. Moreover, the structural changes were analyzed with scanning electron microscopy (SEM), Fourier transform infrared (FTIR) radiation, and thermogravimetric analysis (TGA). The results show that the materials have Fickian characteristics in the aging environment. Specifically, the water sorption rates of HDPE and LDPE increase first and then decrease after reaching saturation (Ms); those of U-PVC and Hi-PVC its increasing continuously with different rate. This behavior of materials was prominent for ClO 2 at high temperature and disinfectant dose because of polymeric chains crosslinking and rearrangement, extraction of monomers, and stable compounds removal during aging under exposed conditions. The deleterious effects decreased the activation energies of the materials and increased the concentrations of carbonyl groups [CO] via the formation of ketones, aldehydes, and carboxylic acids. The decomposition temperature increased with the changes in the material morphology and elemental contents under the investigated conditions. Moreover, LDPE and Hi-PVC were more severely affected in the thermal aging process with 10 mg.L−1 ClO 2 at 80 °C. [Display omitted] • Materials show Fickian behavior under investigated conditions. • Increase in Ms and decrease in Ea with decreasing equilibrium time during aging. • ClO 2 and 80 °C have stronger effects on LDPE and Hi–PVC. • Increase in decomposition temperature due to increase in crosslink density. [ABSTRACT FROM AUTHOR]

Addition of chlorine dioxide (ClO 2) or sodium hypochlorite (NaOCl) as a disinfectant in municipal water distribution systems is a common practice to deactivate micropollutants, but their impact on the pipe material with long-term exposure has not been discussed in detail. In this study, accelerated aging experiments were conducted for evaluating the oxidation of high-density polyethylene (HDPE), low-density polyethylene (LDPE), unplasticized polyvinylidene chloride (UPVC), and high-impact polyvinylidene chloride (Hi-PVC) pipes. The pipes were immersed in deionized (DI) water, ClO 2 , and NaOCl (2 mg/L, 5 mg/L, and 10 mg/L doses) for 1200 h of aging at 40 °C. The variations in the pipes structural, thermal, and mechanical characteristics were systematically investigated by attenuated total reflectance-Fourier transform infrared radiation (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and a universal testing machine (UTM). The formation of carbonyl groups due to methylene groups (C–C/C–H) oxidation resulted in an increased carbonyl index (CI) of the material exposed to accelerated aging conditions. Moreover, the XPS and ATR-FTIR results elucidated that the oxidation patterns under the exposure conditions followed from ketone/aldehyde formation to carboxylate groups (carboxylic acid/ester). The pipes were more vulnerable to the ClO 2 compared to the DI water and NaOCl solution exposure. The increase in crystallinity and the decrease in oxidation induction time (OIT) of the pipe materials confirmed that the loss of stabilizer and changes in the chain alignment resulted in chain secession, loss of ductility, and lower percent elongation at break. Furthermore, results also elucidated that oxidative stability of the HDPE/UPVC was greater than that of the LDPE/Hi-PVC under disinfectant exposure regardless of the concentration and duration. [Display omitted] • Chlorine dioxide effects more severely to pipes materials. • Oxidation stability of HDPE/UPVC > LDPE/Hi – PVC. • Degradation follows the formation of Ketones/aldehydes.→ carboxylate groups • PVC pipes mechanical strength were susceptible under chemical attack. [ABSTRACT FROM AUTHOR]

Abstract: Currently, polyvinylidene fluoride (PVDF) membranes are widely used because of their chlorine resistance and durability. However, membrane bioreactor (MBR) processes still have obstacles to overcome to be cost effective for wastewater treatment. To overcome these obstacles, stable, long-term operations of MBRs with high permeate flux and low membrane fouling are strongly desired. In this study, both a lab and a pilot scale membrane system with new polytetrafluoroethylene (PTFE)-based flat sheet membrane modules were operated to monitor the effectiveness of chemical backwashing for membrane fouling control. There were two operation modes in the lab experiment. One (MBR2) was applied by chemical backwashing once a day and the other (MBR1) was operated without chemical backwashing. The transmembrane pressure (TMP) remained stable in MBR2 after 25days, while the TMP increased continuously and eventually reached the upper limit in MBR1. The R t (total resistance), R c (cake resistance) and R f (fouling resistance) of both MBR1 and MBR2 were 8.88×1011 m−1, 3.52×1011 m−1, 4.07×1011 m−1 and 5.34×1011 m−1, 2.10×1011 m−1, 1.91×1011 m−1, respectively, after 30days of operation. In the pilot scale test, chemical backwashing had similar effects on R f, but minimal influence on the control of R c. Chemical backwashing was effective for controlling R f, but there were differences in R c reduction by aeration according to membrane position. High quality effluent from filtration indicated that the activity of the microorganisms had not been harmed by chemical backwashing. Through lab and pilot scale experiments, it was confirmed that using a PTFE flat sheet membrane with chemical backwashing in an MBR system could provide high flux, twice as much as that from a conventional system. In conclusion, PTFE membranes have significant potential as next generation membrane materials replacing the currently used PVDF membranes, and chemical backwashing will compensate for the weaknesses associated with the use of flat sheet membranes in field applications. [Copyright &y& Elsevier]

Abstract: Oxidative stress regulates cellular functions in multiple pathological conditions, including bone formation by osteoblasic cells. To elucidate the protective effects of dehydrocostus lactone on the response of osteoblast to oxidative stress, osteoblastic MC3T3-E1 cells were incubated with 0.3mM hydrogen peroxide (H2O2) and/or dehydrocostus lactone (0.1–10μg/ml), and markers of osteoblast function and oxidative damage were examined. Dehydrocostus lactone (0.1–10μg/ml) significantly increased osteoblast growth compared with control (P <0.05). H2O2-induced reduction of differentiation markers such as alkaline phosphatase (ALP), collagen content, and calcium deposition was recovered in the presence of dehydrocostus lactone (0.4–2μg/ml). Treatment with dehydrocostus lactone (10μg/ml) decreased the production of osteoclast differentiation-inducing factors such as interleukin (IL)-6 and receptor activator of nuclear factor-kB ligand (RANKL) in the presence of H2O2. Moreover, dehydrocostus lactone (0.4–2μg/ml) decreased the formation of protein carbonyl (PCO) and malondialdehyde (MDA) induced by H2O2 in osteoblasts. Taken together, these results demonstrate that dehydrocostus lactone can protect osteoblasts against H2O2-induced cellular dysfunction. These results also suggest that dehydrocostus lactone may be valuable as a protective agent against oxidative damage in osteoblasts. [Copyright &y& Elsevier]

The neurotoxic mechanism of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has not been completely elucidated. In this study we investigated the possible role of cell cycle regulators and their dependence on arylhydrocarbon receptor (AhR) in the TCDD-mediated inhibition of cell proliferation using a human neuronal cell system. TCDD suppressed DNA synthesis of SK-N-SH human neuronal cells determined by [3H]thymidine incorporation which was significantly prevented either by pretreatment with α-naphthoflavone (α-NF), a partial AhR antagonist, or 8-methoxypsoralen (MOP), a binding inhibitor of activated AhR to dioxin response elements. Cell cycle analysis showed that TCDD induced a G1 cell cycle arrest, which was also significantly prevented by pretreatment with α-NF and MOP. TCDD did not alter the expression of cyclin D, cyclin E, p21 and p53. However, TCDD induced an enhanced expression of p27 and a hypophosphorylation of pRb, which was prevented by α-NF and MOP. Combined, these results suggest that the TCDD-induced inhibition of neuronal cell proliferation may be due to the AhR-dependent G1 arrest through an enhanced expression of p27 and a hypophosphorylation of pRB. [Copyright &y& Elsevier]

The purpose of this study is to manufacture lightweight aggregates for the recycling of water treatment sludge (WTS), to identify the physical properties of the aggregates, and to present a means by which to utilize the manufactured lightweight aggregates. The chemical composition and thermal properties were examined via a raw materials analysis. The aggregate examined here was fired by the rapid sintering method and the single-particle density and water absorption rate were measured. WTS has a high LOI and the calcined inorganic material has high refractoriness. When 30 wt% of purified sludge was added, the single-particle density of the aggregates was in the range of 0.8–1.2g/㎤ at temperatures of 1150–1200 °C. At temperatures of 1200 °C or higher, ultra-lightweight aggregates having a single-particle density of 0.8 or less could be produced. When applied to concrete by replacing the general aggregate in the concrete, a specimen with strength values of 20–45 ㎫ at 28 days was obtained, and when applied as a filter material, the performance was equal to or exceeded that of ordinary sand. [ABSTRACT FROM AUTHOR]

Electrochemical reactions such as the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and methanol oxidation reaction (MOR) are essential for energy conversion applications such as water electrolysis and fuel cells. Furthermore, Pt or Ir-related materials have been extensively utilized as electrocatalysts for the OER, ORR, and MOR. To reduce the utilization of precious metals, innovative catalyst structures should be proposed. Herein, we report a bi-metallic phosphide (Ni 2 P and PdP 2) structure surrounded by graphitic carbon (Ni–Pd–P/C) with an enhanced electrochemical activity as compared to conventional electrocatalysts. Despite the low Pd content of 3 at%, Ni–Pd–P/C exhibits a low overpotential of 330 mV at 10 mA cm−2 in the OER, high specific activity (2.82 mA cm−2 at 0.8 V) for the ORR, and a high current density of 1.101 A mg−1 for the MOR. The superior electrochemical performance of Ni–Pd–P/C may be attributed to the synergistic effect of the bi-metallic phosphide structure and core-shell structure formed by graphitic carbon. [Display omitted] • Bi-metallic phosphide surrounded by graphitic carbon as an electrocatalyst was synthesized. • The electrocatalyst showed an enhanced activity compared to conventional catalysts. • The superior performance may be attributed to the synergistic effect and core-shell structure. [ABSTRACT FROM AUTHOR]

Highlights: [•] We show the effect of surface treatment between the Al2O3 and the recess-etched GaN. [•] We have investigated the effect of TMAH surface treatment. [•] The C–V characteristics were improved with the surface treatment. [•] We result low effective oxide charge and interface trap density. [•] We result less charge trapping in the gate dielectric. [Copyright &y& Elsevier]

Highlights • AlGaN/GaN heterostructures were grown with the AlIn(Ga)N back barrier grown at 400 torr was almost lattice-matched to GaN layer. • The AlGaN/GaN heterostructures with 10 and 15 nm-thick AlIn(Ga)N back barrier exhibited improved 2-DEG properties, compared to those of the conventional AlGaN/GaN heterostructure without the back barrier. • The high electron mobility transistors (HEMTs) fabricated on the AlGaN/GaN heterostructure with a 15 nm-thick AlIn(Ga)N back barrier exhibited a very low off-state leakage current of ∼2 × 10−7 A/mm. Abstract AlGaN/GaN heterostructures were successfully grown with the AlIn(Ga)N back barrier at 900 °C. However, the atomic composition of the AlIn(Ga)N layer was strongly dependent on the growth pressure, which resulted in a different lattice constant of the layer. The AlIn(Ga)N back barrier grown at 400 torr was almost lattice-matched to GaN layer. The AlGaN/GaN heterostructures with 10 and 15 nm-thick AlIn(Ga)N back barrier exhibited improved 2-DEG properties, compared to those of the conventional AlGaN/GaN heterostructure without the back barrier. The high electron mobility transistors (HEMTs) fabricated on the AlGaN/GaN heterostructure with a 15 nm-thick AlIn(Ga)N back barrier exhibited a very low off-state leakage current of ∼2 × 10−7 A/mm which is about 1 order lower in magnitude than the value of the device without the back barrier. The AlIn(Ga)N back barrier is a promising candidate as an alternative to conventional AlGaN and InGaN back barrier. [ABSTRACT FROM AUTHOR]

GaN gate-all-around ( GAA ) vertical nanowire MOSFET ( VNWMOSFET ) with channel length of 300 nm and diameter of 120 nm, the narrowest GaN-based vertical nanowire transistor ever achieved from the top-down approach, was fabricated by utilizing anisotropic side-wall wet etching in TMAH solution and photoresist etch-back process. The VNWMOSFET exhibited output characteristics with very low saturation drain voltage of less than 0.5 V, which is hardly observed from the wide bandgap-based devices. Simulation results indicated that the narrow diameter of the VNWMOSFET with relatively short channel length is responsible for the low voltage operation. The VNWMOSFET also demonstrated normally-off mode with threshold voltage ( V TH ) of 0.7 V, extremely low leakage current of ∼10 −14  A, low drain-induced barrier lowering ( DIBL ) of 125 mV/V, and subthreshold swing ( SS ) of 66–122 mV/decade. The GaN GAA VNWMOSFET with narrow channel diameter investigated in this work would be promising for new low voltage logic application. [ABSTRACT FROM AUTHOR]