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Background：Retinopathy of prematurity (ROP) is one of the leading causes of babies’ visual impairment and blindness. There is no effective intervention with ROP so far, and thus a deeper understanding of oxygen-induced metabolism may offer novel potential therapeutic approaches to ROP. The aim of this study is to explore a correlation of oxygen-induced renal metabolism with those in eyes and blood from ROP patients or a mouse model of oxygen-induced retinopathy (OIR). Methods：At postnatal day 7 (P7), 30 healthy C57BL6/J mice were randomly selected and divided into two groups, an OIR group and a WT group. The R-OIR group (N = 8) and R-WT group (N = 8) were examined for renal untargeted metabolomics; Targeted metabolomics analysis was performed to detect vitreous in V-OIR group (N = 7) and V-WT group (N = 7). Network association analysis was performed with the above results and previous studies: retinal-targeted metabolomics of OIR and human blood-targeted metabolomics of ROP. Results：The levels of metabolites in the R-OIR group were slightly higher than those in the R-WT group, especially in lipids. However, nucleotides of the R-OIR group were lower than the R-WT group. There were 9 canonical signaling pathways enriched, in which the initiation and progression of pathologic retinal neovascularization were closely associated with purine metabolism, arginine biosynthesis, histidine metabolism, pantothenate and CoA biosynthesis, alanine, aspartate and glutamate metabolism; arginine and proline metabolism, tryptophan metabolism, beta-Alanine metabolism, and D-glutamine as well as D-glutamate metabolism. In addition, L-histidinol, Isoguanosine, guanosine, guanine, nicotyrine, quinoxaline-2-carboxylic acid, L-3-hydroxykynurenine, N-gamma-glutamyl-S-propylcysteine, alanine, adenosine diphosphate, and ribose were potential biomarkers of ROP. Conclusion：Shikimic acid and PC(14:1(9Z)/20:2(11Z,14Z)) are highly specific biomarkers of renal metabolomics of OIR. Arginine biosynthesis is the best common pathway of kidney-untargeted OIR metabolomics, vitreous-, and retina-targeted OIR metabolomics, and blood-targeted metabolomics of ROP, indicating that arginine biosynthesis is the common pathway of ROP and neonatal kidney injury.

This study investigates the application of bypass coupling twin-wire indirect arc welding (BC-TWIAW) in arc additive manufacturing of 18–8 stainless steel. It is found that the droplet transfer changed from short circuit mode to stable spray mode with the welding current rising. Droplet transfer was the most stable when welding current was 200 A. Compared with the conventional MIG welding arc additive manufacturing, the efficiency of BC-TWIAW additive manufacturing can be increased by more than 30%. Electrochemical tests show that the BC-TWIAW overlay has a lower reactivation rate, higher charge transfer resistance, and lower carrier concentration, indicating that the overlay has better resistance to intergranular corrosion and pitting corrosion.

The friction stir welding joint of 7N01 aluminum alloy has strong stress corrosion sensitivity due to the inhomogeneity of microstructure. In this paper, the stress corrosion behavior of 14 mm thick plate 7N01-T4 welding joint and base metal was investigated by means of electrochemical impedance spectroscopy, slow strain rate tensile test and electron back scattered diffraction. The results show that the charge transfer resistance of the welding joint is obviously lower than that of the base metal. The lowest impedance at the joint is 698 Ωcm2, but the lowest impedance is 1082 Ωcm2 at the base metal.The lowest Rct value at the weld is only 64.5% of the base metal. The thermal-mechanical affected zone on the rear side is the worst area of the resistance to stress corrosion. There are more deformed grains and larger Schmidt factor close to 0.5 in this area, and the different grain orientation can easily lead to the concentration of internal tensile stress and the formation of crack propagation.

Bimetallic Ni–Fe phosphide electrocatalysts were in-situ synthesized through direct phosphorization of metal salts on carbon cloth (CC). The Fe dopant remarkably enhances the OER performance of Ni2P in alkaline medium through the electronic structure modulation of Ni. The (Fe0.5Ni0.5)2P/CC electrode, composed of uniform films coated on carbon fibers, delivers a low overpotential of 260 mV with a small Tafel slope of 45 mV·dec−1 at the current density of 100 mA cm−2, outperforming most reported non-noble electrocatalysts and commercial RuO2 electrocatalyst. The (Fe0.5Ni0.5)2P/CC also displays superior electrochemical stability at high current density. An appropriate Fe dopant level facilitates the in-situ transformation of Ni–Fe phosphides into active NiFeOOH during alkaline OER. This work simplifies the synthesis procedure of metal phosphides.

Pre-rolling deformation is a preferable procedure in practice, compared to pre-stretching, to improve the performances of the rolled Al–Cu–Li plates. In the present work, the different strains of pre-rolling were applied to a rolled Al–Cu–Li alloys before aging. The influence of pre-rolling on mechanical properties and precipitates during 200 °C aging was carefully investigated through hardness test, tensile test, and microstructure characterization. It was found that the aging precipitation behavior was rather complicated for the not pre-rolled samples, various abnormal precipitates were precipitated along with the large diameter and low-density of T1 (Al2CuLi) phase after a period of aging. After pre-rolling, the nucleation of T1 phase was greatly promoted while the formation of other phases was inhibited, resulting in the precipitation behavior became dominated by the high density and tiny T1 phase. Furthermore, the precipitation kinetics of the T1 phase was continually accelerated by increasing the pre-stain, which facilitated the more rapid aging response, higher T1 phase density and continuous improvement of mechanical properties. The strain of pre-rolling could be increased to 20% to obtain the optimal properties, and the tensile strength of the 20% pre-rolled samples increased to ∼520 MPa in peak aged state, compared to ∼360 MPa of the samples only T6 tempered.

With the development of bypass-coupling technique, the process window of twin-wire indirect arc welding has been effectively broadened, but the process stability is required to be further improved. In this paper, the influence of arc voltage on the stability of welding process was investigated through process experiments. It was found that the direct arc and indirect arc were alternately ignited. Under the condition of the output voltage at 32 V, the ratio of the indirect arc current to overall welding current was the largest. The weld was well formed with the output voltage above 32 V. Considering both the deposition efficiency and process stability, the desirable output voltage was 32 V.

Amorphous Ni–W–P coatings were prepared by electroless plating and annealed at 250[Formula: see text]C for different times to obtain different microstructures. The local atomic structure of these amorphous coatings was analyzed by calculating the atomic pair distribution function from the XRD patterns. The type of crystals in coatings was obtained from the TEM image and corresponding selected area diffraction (SAED) pattern. The proportion of microscopic particles in the matrix was roughly estimated from the first DSC exothermic peak area. Corrosion resistance in 0.5-M sulfuric acid solution was investigated via electrochemical techniques. Experimental results showed that all annealed coatings still held amorphous structure, albeit the microstructure had been changed. The correlation radius and the atomic number of clusters had increased, especially when the annealed time extended to 12 h and 20 h. The number of microscopic particles in the amorphous matrix also increased with rise in heat treatment time. The type of crystals in these amorphous matrices increased from Ni/Ni (W) to Ni/Ni (W), Ni12P5 and Ni5P4. The decreasing corrosion resistance was in agreement with the increasing number of microscopic particles and higher-order clusters in annealed Ni–W–P coatings. These microscopic particles could form micro-galvanic cells in corrosion solution. The higher-order clusters increased the composition difference in the amorphous matrix, and this also promoted to form micro-galvanic cells in solution.

Background The incidence rates of thyroid tumors and nodular goiter show an upward trend worldwide. There are limited reports on the risk of perchlorate and iodine on thyroid tumors, but evidence from population studies is scarce, and their impact on thyroid function is still uncertain. Therefore, the objective of this study was to investigate the association of perchlorate and iodine with the risk of nodular goiter (NG), papillary thyroid microcarcinoma (PTMC), and papillary thyroid carcinoma (PTC) and to assess the correlation between perchlorate and iodine with thyroid function indicators. Methods A case–control population consisting of 184 pairs of thyroid tumors and nodular goiter matched by gender and age (±2 years) was recruited in this study. Serum and urine samples were collected from each participant. Thyroid function indicators in serum were tested by automatic chemical immunofluorescence, and perchlorate and iodine levels in urine were determined by ultra-high performance liquid chromatography tandem-mass spectrometry and inductively coupled plasma-mass spectrometry, respectively. Conditional logistic regressions and multiple linear regressions were used to analyze the associations. Results Urinary perchlorate concentration was significantly higher in total cases, NG and PTC than in the corresponding controls (P, Patients with thyroid tumor have higher perchlorate exposure than control.Perchlorate can increase the risk of papillary thyroid carcinoma.Perchlorate can disturb the homeostasis of thyroid function.Perchlorate was positively correlated with thyroglobulin antibody. Supplementary Information The online version contains supplementary material available at 10.1186/s12940-021-00818-8.

The effect of retrogression re-aging treatment (RRA) on the corrosion behavior of 7055 Al-Zn-Mg alloy was studied in this paper. Results provided that corrosion resistance could be greatly improved by RRA. After the RRA treatment, the isolated precipitates occurred on grain boundaries (GBs) and the low angle grain boundaries (LAGBs) presented a larger fraction compared to that of single-stage peaking aging treatment. The samples after RRA treatment also show better corrosion resistance than that of single-stage peak aging treatment. In addition, of the electrochemical impedance spectroscopy (EIS) analysis showed that the impedance spectrum was consisted of semi-infinite layer diffusion impedance and stagnant Weber impedance. The semi-infinite layer diffusion impedance corresponded to a limited retention layer on the electrode surface while the Weber impedance represented a stagnant layer of corrosion products generated by the anode branches. The aluminum alloy after RRA treatment achieved higher Rf and low Cf, Cp values and its corrosion current density was ten times smaller compared to the single-stage peak aging samples with the 10% hardness losing.

The bypass coupling technique was employed on twin-wire indirect arc welding (TWIAW) to improve its penetration. In bypass coupling twin-wire indirect arc welding, the cathode current can be adjusted by changing the cathode-wire feeding speed. The melting efficiency increases with the cathode-wire current. At the same total current, the deposition and dilution rates of twin-wire indirect arc welding with bypass coupling is twice and a third those of conventional gas metal arc welding, respectively, which are good for low-heat input welding, such as surfacing. High-speed camera observation indicated that the cathode droplet transfer mode changes from free transfer to contact transfer with the increase of the cathode-wire current. The repulsion force of the anode droplet to the cathode wire increases with the increase of the cathode-wire current.

Phosphorus (P) is essential macronutrient for soybean [Glycine max (L.) Merr.] growth and function. The objective of this study was to determine effect of phosphorus nutrition (including phosphorus...

EBSD (electron backscattered diffraction) was used to study the fatigue crack propagation mechanism in a friction stir welding joint of a 15 mm-thick 7N01 aluminum alloy plate. Crack tips with detailed features were clearly characterized by EBSD images. The plastic zone caused by crack was small in the stir zone. Due to the fine grain strengthening in the stir zone, there were several lattice distortion regions which were observed in the BC (band contrast) map but disappeared in the SEI (secondary electron image). In the stir zone, fatigue crack tends to awake and grow along grain boundaries, and propagate with little deformation of the grains. When the crack tries to grow across a boundary, the deformation of the plastic zone at the crack tip shows little correlation to the cyclic loading direction. However, the plastic zone in base metal, the rolled plate, is large and continuous, and no obvious lattice distortion region was found. According to Schmidt factor, the base metal near crack is fully deformed, lots of low angle boundaries parallel to the cyclic force can be observed. The base metal showed a better ability for fatigue crack propagation resistance.

Supersonic atmosphere plasma sprayed Cr3C2-NiCr coatings have been gradually used for protecting industrial components from the severe wear and corrosion attack. In this study, the pulsed laser technique was applied to remelt the deposited Cr3C2-NiCr coatings. The evolution in microstructure and corrosion resistance between the as-sprayed coating and pulsed laser remelted coating was carefully investigated. It is found that desirable metallurgical bonding was achieved between the pulsed laser processed coating and the substrate. After pulsed laser remelting treatment, the metastable phase disappeared and the coating was composed of equilibrium phases of Cr7C3 and Ni-crystal. Interestingly, the morphology of the newly formed carbides became regular and the high-speed Marangoni flow inside the molten pool facilitated their homogeneous distribution. Overall, the porosity decreased from 4.3% of the as-sprayed coating to 1.1% of the laser-treated coating while the carbide volume fraction increased from 49% to 70%. Due to that the coating microstructure became more homogeneous and denser after pulsed laser remelting, the hardness and corrosion resistance were greatly improved.

Solid solutions Ti3(Al1−xSix)C2 (x = 0–1) were successfully fabricated by hot pressing with the powder mixture Ti/Al/TiC/Si. The difference on variations between the linearly decreased c-lattice parameter and the nearly constant a-lattice parameter suggested the strong anisotropy of MAX phase lattices. Vickers hardness increased after Si addition due to the solid solution hardening effect brought by Al-Si alloying in the A sites, reached the maximum at 504.46 Hv of Ti3Al0.4Si0.6C2, and slightly decreased because of the increased grain size. All Ti3(Al1−xSix)C2 solid solution passivated in 3.5% NaCl solution with the N-type-semiconductor-feature passive films formed on the surface. With the increasing Si addition, the increased resistance of charge transfer and the reduced corrosion current density implied the increased corrosion obstruction and performance. With the increase in Si addition, the content of SiO2 in the passive films increased, and the donor carrier concentration reduced, thereby enhancing the corrosion resistance. Accordingly, the corrosion difficulty and resistance were enhanced.

The welding characteristics in the process of bypass coupling twin-wire indirect arc welding (BC-TWIAW) with high-speed welding mode was comprehensively investigated. Under the condition of the total current of 300 A, the direct arc and indirect arc mainly periodically burned alternately. Its alternating frequency increased with cathode wire feeding speed increase. Nevertheless, it is also found that these two arc burned simultaneously for a very short duration. The indirect arc between the twin wires was principally used for melting the wire while the direct arc was beneficial for deepening the molten pool. Overall, the alternating burning of two arcs could remarkably reduce the heat input into the workpiece. Irrespective of the cathode wire feeding speed, the arc voltage and total welding current generally remained stable. Meanwhile, the droplet transfer patterns changed periodically accompanying with the alternative burning between the two arcs. The droplets of cathode wire mainly transferred into the molten pool globularly. When the cathode wire feeding speed was slow, the droplets of anode wire was mainly in stable spray transfer mode. The anode wire droplet successively experienced spray transfer, short circuiting transfer and globular transfer in turn with the acceleration of cathode wire feeding. Even though the deposition efficiency was improved with a faster cathode wire feeding speed, too fast feeding speed might lead to frequent short circuit explosion and impair the weld formation. Considering both the deposition efficiency and weld formation, the feeding speed of cathode wire should be adjusted at 40%–50% of the anode wire.

In this study, we prepared a micro-nano hierarchical structure superhydrophobic 7055 aluminum alloy surface. The preparation mechanism, the surface topographies, the wettability, and the chemical compositions were characterized and discussed in detail. Results show that electrolytic polishing (EP) and etching can effectively inhibit the continuous growth of corrosion products and take grains as a unit, which has micron petal-shaped structures with the grain boundary as the boundary. The surface has a great lasting quality and the corrosive ions and liquids can hardly infiltrate the aluminum substrate and avoid the generation of chloride ion channels.

Background Low-density lipoprotein receptor-related protein 5 (LRP5) plays an important role in glucose and cholesterol metabolism. The present cohort study evaluated associations of LRP5 variants with the incidence of type 2 diabetes mellitus (T2DM) in a rural adult Chinese population. Methods In all, 7751 subjects aged ≥18 years without T2DM underwent genotyping at baseline; 6326 subjects (81.62%) were followed-up, and 5511 with a clear disease outcome were eligible for analysis. The same questionnaire was administered and the same anthropometric and blood biochemical examinations were performed at baseline and follow-up. Association analysis was performed for five single nucleotide polymorphisms and haplotypes of LRP5. Results Cox proportional hazards testing of three different genetic models found no significant association between T2DM and LRP5 after adjusting for potential risk factors (P > 0.05). However, the incidence of T2DM in subjects with LRP5 mutational genotypes was higher in the overweight/obese than normal weight population. Under the dominant model, the risk of T2DM was increased with an interaction between rs11228303 and the waist-to-height ratio adjusted for baseline age, sex, and family history of T2DM (synergy index [SI] = 4.172; 95% confidence interval [CI] 1.014–17.166)], and body mass index (SI = 3.237; 95% CI 1.102–9.509). Furthermore, the A allele of rs3758644 was related to decreased fasting plasma insulin and homeostatic model assessment of β-cell function levels, whereas the T allele of rs12363572 was related to increased high-density lipoprotein cholesterol levels in new-onset diabetes patients (P < 0.05). Conclusions The risk of T2DM may be associated with interactions between the LRP5 gene and overweight and obesity. Polymorphisms of LRP5 are related to β-cell function and lipid metabolism.

Although previous studies have reported an association between resting heart rate (RHR) and cancer mortality, the association is contradictory. The relationship between RHR and disease-specific mortality has not been explored in the Chinese population. We examined this relationship in a rural adult Chinese population from a cohort study with a 6-year follow-up. The RHR of a cohort of 20,069 participants was measured between July–August of 2007 and July–August of 2008, and 17,151 participants (85.5 %) were followed up between July–August of 2013 and July –October of 2014. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) for deaths due to all causes, cardiovascular disease (CVD), stroke, cancer, and other causes in RHR groups. Males and females with RHR ≥ 90 showed the highest all-cause mortality (33,27 and 1,226/100,000 person-years) and adjusted HR for all-cause deaths—2.20 (95 % CI 1.64–2.93) and 1.99 (1.43–2.77). A similar association was observed for deaths due to CVD, stroke and cancer (except for females), and other causes of mortality. Elevated RHR may be an independent marker of all-cause, CVD and other causes of death for both sexes and stroke and cancer deaths for males.

Failure analysis of cracking of a GIS aluminum shell which causes SF6 gas leak in a 220 kV substation was present. Visual inspection, microstructure observation, chemical composition and mechanical properties characterization were performed to reveal the forming mechanism of the crack. It is found that the crack is located in the region of the aluminum alloy shell that undergone welding repair. The crack is continuous and develops within the weld metal. Detailed investigation reveals that the crack initiates by the defect of lack of fusion in the welding repaired zone. The working stress induced by gas pressure, combined with the residual stress and vibration stress, results in the extension of the crack and the final leaking of SF6 gas.