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This study conducts stress-controlled cyclic tension-tension tests from room temperature (RT) to 200 °C, at 50 °C intervals, on high-purity Cu films to comprehensively understand the temperature-dependent fatigue life and the related microstructural and fracture characteristics. As evidenced by the electron backscattering diffraction analysis, the Ʃ3 boundary fraction decreases and the low-angle grain boundary fraction increases as the temperature increases. The significant change in the grain structure at high temperatures leads to a reduced fatigue life. The fatigue striations are closely spaced at RT and the fracture surface develops into the typical fatigue striation and the void zones.

Anthracnose caused by Colletotrichum gloeosporioides is one of the most serious postharvest diseases of citrus fruit. Fruit peels infected with C. gloeosporioides and the peels of healthy fruit were analysed for flavonoids, using high performance liquid chromatography–tandem mass spectroscopy, to evaluate variations in flavonoid levels in Citrus benikoji Hort. ex. Tan. Seventeen flavonoids were characterised from the fruit peels. The flavonoids were validated using structurally related standards and quantified. Among the 17 flavonoids, the concentration of component 3 was the highest and that of component 10 was the lowest. During 8 days after inoculation, the concentration of the seven flavonoids 1 – 3 , 5 , 6 , 13 , and 14 increased gradually up to day 8. Flavonoid 4 was detected from day 7. The seven minor flavonoid components, 8 – 12 , 15 , and 16 increased to day 5 and then decreased. However, flavonoids level variations were not significantly different from that of the non-infected fruits during the experimental period. The monitoring suggested that the constitutively formed seven polymethoxyflavones ( 8 – 12 , 15 , and 16 ) may act as phytoanticipins in the defence mechanism against the fungus, and that hespertin 7- O -glucoside ( 4 ), produced de novo on day 6 after infection, may function as a phytoalexin.

Adipokines modulate immune responses and lipid metabolism in allergic disease; however, little is known about their role in the skin barrier and atopic dermatitis (AD). We identified ZAG, an adipokine that regulates lipid mobilization, as a biomarker for AD. ZAG levels were consistently decreased in sera, T cells, and skin in human AD patients compared with healthy controls. ZAG was primarily detected in the stratum corneum along with FLG and LOR. Knockdown of ZAG with short hairpin RNA resulted in decreased FLG and increased TSLP. Topical ZAG treatment in AD mice recovered ZAG expression in the skin and improved AD-like symptoms, transepidermal water loss, and ceramide levels. Furthermore, topical ZAG treatment induced immunoregulatory effects, including reduction of IL-4, IL-17, and IFN-γ and increased Foxp3 in the skin and lymphoid organs. Interestingly, ZAG treatment also recovered decreased levels of ADAM17, an important player in skin barrier function and immune response in AD. Thus, ZAG deficiency is closely related to skin barrier function and the immune abnormalities of AD, and we suggest that restoration of ZAG may be a promising therapeutic option for the treatment of AD.

Three different mixtures of polyphenol components were isolated from the leaf, flower and stem of Lonicera japonica Thunb. via aqueous 70% methanol extraction followed by column chromatography over silica gel. The polyphenolic components of these mixtures were analysed via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS) and compared with the reported data. Among the 25 characterized components, seven hydroxycinnamic acid derivatives and four flavonoid constituents were identified for the first time. The polyphenol compounds were validated and quantified on the basis of a representative polyphenol standard of the same group. The antioxidant activity of the polyphenol mixtures of the three tissues was determined. The antioxidant activity of the leaf was higher than that of the flower and stem.

In order to evaluate the flavonoid level variation in an onion ( Allium cepa L.) infected by Fusarium oxysporum , the bulbs of a healthy onion and of an infected one were analysed for flavonoids via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). Among eleven flavonoids characterised, isorhamnetin 4′- O -galactoside ( 8 ) was identified in an onion for the first time. When the healthy bulb was inoculated with the fungus, the two quercetin derivatives ( 4 and 7 ) and the two isorhamnetin derivatives ( 5 and 9 ) underwent concentration changes typical for the defense materials against pathogens. The yellow granules that were accumulated on the abaxial epidermal cell layers after 8 days of inoculation were confirmed as quercetin ( 10 ) and isorhamnetin ( 11 ). It was deduced that they were produced from flavonoids 4 , 5 , 7 and 9 by hydrolysis enzyme of the fungus.

Healthy fruits of Capsicum annuum L. cv. Chelsea (yellow bell pepper) and one infected by Colletotrichum gloeosporioides were analysed for polyphenols via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). Among seven polyphenols characterized, four components in the C. annuum fruits were identified for the first time. To investigate the characteristics of the polyphenols as defence materials, the content change of the fruit polyphenols inoculated with C. gloeosporioides was monitored by HPLC. It was observed for the first time that de novo induced N-caffeoyl putrescine (1) and caffeoyl O-hexoside (2) appeared to act as a phytoalexin in the defence mechanism of the C. annuum fruits against C. gloeosporioides, and constitutively formed feruloyl O-glucoside (3), kaempferol O-pentosyldihexoside (4) and dihydroxyflavone O-hexoside (7) as a phytoanticipin in the diseased C. annuum fruits.

Orostachys japonicus cultivated in the Republic of Korea was analysed for flavonoid content via HPLC coupled to MS/MS. Amongst 16 compounds that were characterised, eight flavonoids and one alkaloid were characterised for the first time: two procyanidin dimer gallate isomers ( 1 and 2 ), epigallochatechin-3-gallate ( 3 ), two procyanidin dimer digallate isomers ( 4 and 9 ), quercetin 3- O -rhamnosyl-7- O -glucoside ( 6 ), myricetin 3- O -glucoside ( 10 ), kaempferol ( 16 ) and N 1 , N 5 , N 10 -tri- p -( E,E,E )-coumaroylspermidine ( 15 ). The identified compounds were quantified by HPLC–UV/DAD. The antioxidant activity of the O. japonicus flavonoids was determined via 2,2-diphenyl-1-picrylhydrazyl radical (DPPH • ), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS •+ ) and nitric oxide radical (NO • ) scavenging assays.

The principal objective of this study was to develop an appropriate, sensitive, and selective method for the simultaneous quantitative determination of phoxim and its photo-transformation product, O,O-diethyl alpha-cyanobenzylideneamino-thiophosphonate (DCTP) in both chicken and quail eggs. Eggs (1 g) were blended with anhydrous magnesium sulfate (1 g) for sample pretreatment and extracted with acetonitrile. The extracts were then further purified with SPE silica gel tubes deactivated with trimethylamine. Residues were analyzed via a reversed phase-liquid chromatography-tandem mass spectrometry (RP-LC-MS/MS) in positive-ion electrospray ionization (ESI) mode. Tebufenozide was utilized as an internal standard for the quantification of phoxim and its metabolite residues. The identification and quantification of analytes were based on ion transitions monitored by multiple reaction monitoring (MRM). LC-MS/MS analysis was performed from 0.02 to 1 mg kg(-1) and correlation coefficients (r(2)) ranging from 0.998 to 0.999 were obtained for both analytes in blank egg extracts. The relative standard deviations (RSDs) of intra- and inter-day variations ranged from 2.1% to 6.7% and from 2.8% to 6.4% for phoxim and DCTP in chicken and quail eggs. At all levels of fortification (0.02, 0.05, and 0.125 mg kg(-1)), the recoveries fell within a range of 81.3% to 93.6% for phoxim and 83.3% to 90.1% for DCTP. The matrix effect was2%, due to the partial dilution of the sample. Decision limits (CCalpha) and detection capabilities (CCbeta) were in the range of 0.0005-0.0044 and 0.0054-0.0224 mg kg(-1), respectively. The method was evaluated further by analyzing real samples purchased from markets. All chicken and quail egg samples were free from residues of the target compounds.

Special interest has been focused on the variation in the composition and content of phospholipids (PLs) in soybeans following genetic modification, due to their beneficial effects on human health. As part of the attempt to discover PL-rich soybeans, a total of 12 cultivars were bred and their PL contents were determined by LC–MS/MS. In the LC, 0.1 M ammonium formate in methanol was essential to obtain good peak separation with minimum tailing. The LC–MS/MS method operating in the multiple reaction monitoring (MRM) mode, with two transitions monitored for each PL, provided good selectivity and sensitivity for the determination of PLs. All the calibration curves were linear, with correlation coefficients higher than 0.990. The extraction recoveries ranged from 75.6% to 89.9%. The limit of quantitations (LOQs) were within the range of 0.16–16.7 μg/kg. The average content of total PLs in the 12 soybean cultivars was about 75.7 mg/kg. The total PL and PC (phosphatidylcholine) contents were highest in the Gaechuck#2 cultivar. From the viewpoint of the PL content, Gaechuck#2 was demonstrated to be the most improved variety in the 12 cultivars investigated.