Microstructure and Corrosion Behavior of Laser-Welded Al-Mn-Zr Alloy for Heat Exchanger.

In this study, an Al-Mn-Zr alloy was designed and its microstructure and corrosion behavior compared after laser welding to that of AA3003. As the results of immersion and electrochemical tests showed, both alloys had a faster corrosion rate in the fusion zone than in the base metal. Laser welding caused interdendritic segregation, and spread the intermetallic compounds (IMCs) evenly throughout in the fusion zone. This increased the micro-galvanic corrosion sites and destabilized the passive film, thus increasing the corrosion rate of the fusion zone. However, Zr in the Al-Mn alloy reduced the size and number of IMCs, and minimized the micro-galvanic corrosion effect. Consequently, Al-Mn-Zr alloy has higher corrosion resistance than AA3003 even after laser welding.

Derivation of Corrosion Depth Formula According to Corrosion Factors in District Heating Water through Regression Analysis.

In order to predict the corrosion depth of a district heating pipeline, it is necessary to analyze various corrosion factors. In this study, the relationship between corrosion factors such as pH, dissolved oxygen, and operating time and corrosion depth was investigated using the Box-Behnken method within the response surface methodology. To accelerate the corrosion process, galvanostatic tests were conducted in synthetic district heating water. Subsequently, a multiple regression analysis was performed using the measured corrosion depth to derive a formula for predicting the corrosion depth as a function of the corrosion factors. As a result, the following regression formula was derived for predicting the corrosion depth: "corrosion depth (µm) = -133 + 17.1 pH + 0.00072 DO + 125.2 Time - 7.95 pH × Time + 0.002921 DO × Time".

Superiority of coarse eggshell as a calcium source over limestone, cockle shell, oyster shell, and fine eggshell in old laying hens.

Chicken eggshell (ES) waste is a rich source of calcium carbonate (CaCO3); however, the potential of ES as dietary calcium (Ca) in old laying hens has not been explored. This study compared the effects of feeding limestone, cockle shell, oyster shell, fine ES, and coarse ES as the sole Ca source on production performance, egg quality, blood biochemical constituents, and tibia characteristics in old laying hens. A total of 450 ISA-Brown laying hens at 73 wk of age with similar egg production rate (EPR) were randomly assigned to 5 treatment groups (90 hens/group, 9 hens/replicate) for 7 wk. Dietary treatment groups comprised a corn-soybean meal based diet containing different Ca sources: (i) limestone (LS; < 2 mm and 2-4 mm mixed in the ratio of 3:7) as control, (ii) cockle shell (CS; 1-4 mm), (iii) oyster shell (OS; 3-16 mm), (iv) ES fine particles (ESF; < 1 mm), and (v) ES coarse particles (ESC; 3-5 mm). Results indicated that dietary inclusion of coarse ES particles significantly increased average egg weight (P < 0.001) and daily egg mass (P < 0.05), and decreased feed conversion ratio (P < 0.001) as compared with the other treatments. However, no significant differences in EPR, feed intake, cracked egg proportion, and mortality were observed among the dietary treatments (P > 0.05). Notably, the use of ESF led to a lower proportion of cracked eggs than ESC (P < 0.05). ESC fed hens produced the heaviest eggs whereas CS fed hens produced the lightest (P < 0.001); the particle size of ES also affected the egg weight (P < 0.05). The eggs from OS and ESC fed hens showed a greater albumen height in comparison to eggs from CS group (P < 0.05); but no significant difference was observed among the LS, OS, ESF, and ESC groups (P > 0.05). The yolk color was darker in the eggs of group ESF as compared with other dietary groups (P < 0.01). However, no significant effects on Haugh units and shell properties were observed among the treatments (P > 0.05). The blood biochemistry results were not affected by the dietary Ca (P > 0.05) except for lower levels of high-density lipoprotein percentage (HDL %) in OS and ESC fed hens (P < 0.05). The tibia characteristics including weight, length, width, and breaking strength did not differ among the dietary groups (P > 0.05). However, the ESC and OS fed hens showed higher tibia bone mineral density (BMD) than the other groups (P < 0.001). In conclusion, coarse ES as a sole Ca source had beneficial effects on the production performance, egg quality, and tibia BMD in old laying hens.

Calibrating the Impressed Anodic Current Density for Accelerated Galvanostatic Testing to Simulate the Long-Term Corrosion Behavior of Buried Pipeline.

Various studies have been conducted to better understand the long-term corrosion mechanism for steels in a soil environment. Here, electrochemical acceleration methods present the most efficient way to simulate long-term corrosion. Among the various methods, galvanostatic testing allows for accelerating the surface corrosion reactions through controlling the impressed anodic current density. However, a large deviation from the equilibrium state can induce different corrosion mechanisms to those in actual service. Therefore, applying a suitable anodic current density is important for shortening the test times and maintaining the stable dissolution of steel. In this paper, to calibrate the anodic current density, galvanostatic tests were performed at four different levels of anodic current density and time to accelerate a one-year corrosion reaction of pipeline steel. To validate the appropriate anodic current density, analysis of the potential vs. time curves, thermodynamic analysis, and analysis of the specimen's cross-sections and products were conducted using a validation algorithm. The results indicated that 0.96 mA/cm2 was the optimal impressed anodic current density in terms of a suitable polarized potential, uniform corrosion, and a valid corrosion product among the evaluated conditions.

Antioxidant Properties and Diet-Related α-Glucosidase and Lipase Inhibitory Activities of Yogurt Supplemented with Safflower (Carthamus tinctorius L.) Petal Extract.

Recently, yogurt has been extensively studied to further enhance its functions using edible plant extracts. This study was conducted to investigate whether safflower petal (SP) as a natural food additive can be used to develop functional yogurt with improved health benefits. SPs were extracted with ethanol (SPE) and hot water (SPW), and then safflower yogurt was prepared by adding 0%-1.0% of those extracts to plain yogurt. With an increase in the fermentation duration, the pH of SPE and SPW yogurt samples was decreased, whereas titratable acidity and microbial counts were increased. The concentration of total polyphenols and total flavonoids, the activity of antioxidants, and the inhibitory effect on reactive oxygen species (ROS) were higher in SPW yogurt than SPE yogurt. Furthermore, α-glucosidase and lipase activity inhibitory effects of SPW yogurt were higher than those of SPE yogurt. In particular, free radical-scavenging activities, ROS inhibitory effect, and α-glucosidase activity inhibitory effects were significantly increased in SPW yogurt in a dose-dependent manner. Overall, these results suggest that SP extract possesses antioxidant activities and that it can downregulate α-glucosidase and lipase activities. The SP extract may have potential benefits as a natural food additive for the development of functional yogurt.

Laparoscopic Pediatric Inguinal Hernia Repair; Intracorporeal Purse-String Suture Using Needlescopic 2-mm Instruments.

Purpose: Two-millimeter needlescopic instruments induce minimal damage to the abdominal wall and have excellent cosmetic benefits. We aimed to evaluate the feasibility of a laparoscopic intracorporeal suture using 2-mm instruments for pediatric inguinal hernia. Methods: We retrospectively reviewed 131 patients who underwent laparoscopic repair between March 2011 and February 2017. Three trocars were used: a 5-mm umbilical trocar for a needle holder and two 2-mm trocars for a camera and a grasper. The internal ring was closed with an intracorporeal purse-string suture. A telephone interview was conducted to confirm recurrence. Results: In the 131 patients, 169 procedures were successfully performed. The ages ranged from 2 months to 14 years (mean, 52.5 months), and the mean body weight was 18.0 kg (range, 6.7~49 kg). The mean operating time was 42 minutes for the unilateral cases and 46 minutes for the bilateral inguinal hernia repairs. All the cases were completed laparoscopically without intraoperative complications. Herniotomy was not performed in all the patients except nine. A contralateral patent processus vaginalis was present in 27.3% (35/128) of the patients. During the mean follow-up period of 54.6 months, 3 recurrences (2.3%) were observed. Two recurrences were treated using laparoscopy and one using open herniorrhaphy. Hydrocele occurred in one male patient. No wound complications or umbilical hernias developed. No testicular atrophy was observed. Conclusion: This study showed that laparoscopic intracorporeal internal ring suture using 2-mm instruments for pediatric inguinal hernia was technically feasible and safe, with excellent cosmetic results.

Surface Carbon Shell-Functionalized ZrO2 as Nanofiller in Polymer Gel Electrolyte-Based Dye-Sensitized Solar Cells.

We prepare dye-sensitized solar cells (DSSCs) fabricated with a poly (ethylene glycol) based polymer gel electrolytes (PGEs) incorporating surface carbon shell-functionalized ZrO2 nanoparticles (ZrO2-C) as nanofillers (NFs). ZrO2 are polymerized via atom transfer radical polymerization (ATRP) using poly (ethylene glycol) methyl ether methacrylate (POEM) as a scaffold to prepare the ZrO2-C through carbonization. The power conversion efficiency of DSSC with 12 wt% ZrO2-C/PGEs is 5.6%, exceeding that with PGEs (4.4%). The enhanced efficiency is attributed to Lewis acid-base interactions of ZrO2-C and poly (ethylene glycol), catalytic effect of the carbon shells of ZrO2-C, which results in reduced crystallinity, enhanced ion conductivity of electrolytes, decreased counterelectrode/electrolyte interfacial resistance, and improved charge transfer rate. These results demonstrate that ZrO2-C introduction to PGEs effectively improves the performance of DSSCs.

Synthesis of Ag2O decorated hierarchical TiO2 templated by double comb copolymers for efficient solar water splitting.

Synthesis of Ag2O decorated hierarchical TiO2 was realised in this study by employing a facile hydrothermal method, which involved the use of a double comb copolymer templated sol-gel and a chemical bath. The synthesized Ag2O@HNR demonstrated a photocurrent density of 1.78 mA cm-2 at 1.23 V against RHE under an illumination of 1 sun. This observed value of photocurrent density exceeded that of TiO2 nanorods by 2.18 times.

Effects of dietary multi-strain probiotics supplementation in a low fishmeal diet on growth performance, nutrient utilization, proximate composition, immune parameters, and gut microbiota of juvenile olive flounder (Paralichthys olivaceus).

A 12-week feeding trial was conducted to evaluate the effects of multi-strain probiotics (MSP) in a low fish meal (FM) diet on overall performance, gut microbiota, selected non-specific immune responses and antioxidant enzyme activities of olive flounder (Paralichthys olivaceus) juveniles. A total of 225 healthy olive flounders (initial mean body weight, 13.5 ±â€¯0.01 g) were randomly separated into 3 groups of 75 fish, each group having three replicates of 25 fish; first group was fed with a FM-based control diet (Con), 2nd group was fed with a low-FM diet containing a blend of plant and animal protein meals replacing 30% of the FM protein (FM30), and 3rd group was fed with the FM30 diet supplemented with 108-109 CFU kg-1 of the MSP (Pro). With the exception of lipid retention, which was significantly lower in fish fed the FM30 diet compared to the other two treatments, no other statistically significant differences were recorded with respect to any of the other growth and nutrient utilization parameters. Myeloperoxidase and lysozyme activities of fish fed the Pro diet were much higher and significantly different than those of fish fed the FM30 diet. Glutathione peroxidase activity was significantly higher in Pro- than in Con-fed fish, which, in turn, was significantly higher than FM30-fed fish. Expression of immune-related genes including IL-1ß, IL-6, and TNF-α was markedly upregulated in livers of the fish fed Pro diet compared to those fed the Con and FM30 diets. Furthermore, supplementation of MSP in FM30 diet enriched the Lactobacillus abundance in the fish gut as well as predictive gene functions in relation to lipid and carbohydrate metabolisms. These data suggested that the MSP could reduce the potential adverse effects of the low-FM diet and might be used as a healthy immunostimulant for olive flounder.

Autochthonous Bacillus licheniformis: Probiotic potential and survival ability in low-fishmeal extruded pellet aquafeed.

In recent years, Bacillus spp. have garnered attention as probiotic supplements in aquafeed owing to the production of heat stable and low pH resistant spores. Herein, we isolated and characterized an autochthonous Bacillus licheniformis KCCM 43270 from the intestine of olive flounder (Paralichthys olivaceus) for supplementation in low-fishmeal extruded aquafeeds. The KCCM 43270 was screened based on amylase, protease, cellulase, and lipase as well as non-hemolytic activities. The isolate was able to grow in carboxymethyl cellulose (CMC), xylan, and soybean meal (SBM) when used as a single carbon source in the minimal nutrient M9 medium. The KCCM 43270 spores displayed complete survival in acid (pH 2.5) and bile (0.3%, w/v) for 3 hr, strong biofilm formation, and nearly 50% adhesion with intestinal mucus. The spores of the isolate also showed significant survival ability at 80, 90, 100°C for 60, 30, and 1 min, respectively. In addition, the spores in a blend of SBM complex carrier showed significant heat stability at 120°C for 5 min and under different drying conditions. Furthermore, the spores also survived the extrusion process during low-fishmeal aquafeed manufacturing, implying the potential application of B. licheniformis KCCM 43270 in aquafeed industry.

Effect of peiminine on DNCB-induced atopic dermatitis by inhibiting inflammatory cytokine expression in vivo and in vitro.

Peiminine (PMN) is the main component derived from Fritillaria ussuriensis and is used in traditional medicine in East Asia. The aim of this study was to evaluate the effects of PMN on atopic dermatitis (AD) induced by a dinitrochlorobenzene (DNCB) in Balb/c mice. Inflammatory cytokine expression of PMN was investigated in vitro. Eosinophil infiltration and the thickness of DNCB-induced AD mouse skin were measured. The levels of IgE, IL-4, IL-6, IL-13, and TNF-α in the serum were measured by ELISA. The effects of PMN on the transcription level of MAPK and nuclear factor (NF)-κB were evaluated in mouse skin. In addition, the inhibitory effect of TNF-α, IL-1ß, COX-2 and PGE2 were measured in RAW264.7 cells; TARC was investigated in HaCaT cells; and ß-hexosaminidase was examined in RBL-2H3 cells. PMN decreased the number of eosinophils in the dermis as well as mast cells and decreased the thickness of the epidermis and dermis. The PMN High group had a significantly reduced serum level of IgE, IL-4, IL-13 and TNF-α. Moreover, P-ERK and P-P38 were inhibited in the PMN High group compared with the DNCB-treated group. PMN additionally attenuated the expression of inflammatory cytokines in cells, including RAW264.7, HaCaT and RBL-2H3 cells. Our results suggest that PMN could be a potential therapeutic candidate for the treatment of AD.

The effects of Lycii Radicis Cortex on RANKL-induced osteoclast differentiation and activation in RAW 264.7 cells.

Post-menopausal osteoporosis is a serious age-related disease. After the menopause, estrogen deficiency is common, and excessive osteoclast activity causes osteoporosis. Osteoclasts are multinucleated cells generated from the differentiation of monocyte/macrophage precursor cells such as RAW 264.7 cells. The water extract of Lycii Radicis Cortex (LRC) is made from the dried root bark of Lycium chinense Mill. and is termed 'Jigolpi' in Korea. Its effects on osteoclastogenesis and post­menopausal osteoporosis had not previously been tested. In the present study, the effect of LRC on receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast differentiation was demonstrated using a tartrate-resistant acid phosphatase (TRAP) assay and pit formation assay. Moreover, in order to analyze molecular mechanisms, we studied osteoclastogenesis-related markers such as nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), c-Fos, receptor activator of NF-κB (RANK), TRAP, cathepsin K (CTK), matrix metallopeptidase-9 (MMP-9), calcitonin receptor (CTR) and carbonic anhydrase Ⅱ (CAII) using RT-qPCR and western blot analysis. Additionally, we also determined the effect of LRC on an ovariectomized (OVX) rat model. We noted that LRC inhibited RANKL-induced osteoclast differentiation via suppressing osteoclastogenesis-related markers. It also inhibited osteoporosis in the OVX rat model by decreasing loss of bone density and trabecular area. These results suggest that LRC exerts a positive effect on menopausal osteoporosis.

Antiallergic effect of gami-hyunggyeyeongyotang on ovalbumin-induced allergic rhinitis in mouse and human mast cells.

BACKGROUND: Gami-hyunggyeyeongyotang (GMHGYGT) is a polyherbal medicine derived from an oriental prescription traditionally used in the treatment of allergic diseases such as allergic rhinitis (AR). This study aimed to evaluate the effects of GMHGYGT on ovalbumin (OVA) sensitization/challenge-induced AR in BALB/C mice, through examination of allergic inflammatory response regulation, as well as examination of human mast cells (HMC-1). METHODS: Nasal symptoms were evaluated in the OVA-induced allergic rhinitis mouse model, and total immunoglobulin (Ig)E and OVA-specific IgE levels in serum were investigated. Eosinophil infiltration and thickness of the nasal mucosa, and levels of interleukin (IL)-1ß and caspase-1 were also measured by immunohistochemistry. Additionally, the effect of GMHGYGT on the phorbol-12-myristate-13-acetate plus calcium ionophore A23187-induced phosphorylation of extracellular signal-regulated kinase, C-Jun N-terminal kinase and p38 in HMC-1 cells was investigated. RESULTS: GMHGYGT was demonstrated to have antiallergic effects on the nasal symptoms of the OVA-induced mouse model, decreasing serum levels of OVA-specific IgE and levels of the cytokines IL-5, IL-6, IL-1ß, monocyte chemotactic protein-1, and macrophage inflammatory protein-2. GMHGYGT reduced the number of eosinophils in the nasal mucosa and thickness of the nasal septum, and inhibited the expression of IL-1ß and caspase-1. Moreover, it inhibited the phosphorylation of extracellular signal-regulated kinase and C-Jun N-terminal kinase, as well as the activation of nuclear factor-κB on protein level in HMC-1 cells. CONCLUSION: These results suggest that GMHGYGT has therapeutic potential for the treatment of allergic rhinitis.