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AISI 304 austenitic stainless steel was ion implanted with tungsten and the improvement in surface hardness and fretting wear was investigated. The W ion implantation was carried out using a metal vapor vacuum arc (Mevva) ion source, with a mean energy of 105 ke V under a current density of 22 µA/cm² and at doses of 3 x 1017 cm² … 5 x 1017 cm². Micro-hardness and {retting wear of the implanted samples were measured and compared to the unimplanted substrate. The area of fretting scar was decreased by 32% to 48% after W ion implantation, which should be attributed to the hardening effects and high compressive residual stress generated by ion implantation. Owing to the defect hardening and solution hardening, the near-surface hardness was improved by a {actor of three after the ion implantation. [ABSTRACT FROM AUTHOR]

A discharge channel with a chamfered wall not only has application in the design of modern Hall thrusters, but also exists where the channel wall is eroded, and so is a common status for these units. In this paper, the laws and mechanisms that govern the effect of the chamfered wall on the performance of a Hall thruster are investigated. By applying both experimental measurement and particle-in-cell simulation, it is determined that there is a moderate chamfer angle that can further improve the optimal performance obtained with a straight channel. This is because the chamfering of the wall near the channel exit can enhance ion acceleration and effectively reduce ion recombination on the wall, which is favorable to the promotion of the thrust and efficiency. However, the chamfer angle should not be too large; otherwise, both the density of the propellant gas and the distribution of the plasma potential in the channel are influenced, which is undesirable for efficient propellant utilization and beam concentration. Therefore, it is suggested that the chamfer shape of the channel wall is an important factor that must be carefully considered in the design of Hall thrusters. [ABSTRACT FROM AUTHOR]

Background: As one of the leading causes of child mortality, deaths due to congenital anomalies (CAs) have been a prominent obstacle to meet Sustainable Development Goal 3.2., Objective: We conducted this study to understand the death burden and trend of under-5 CA mortality (CAMR) in Zhejiang, one of the provinces with the best medical services and public health foundations in Eastern China., Methods: We used data retrieved from the under-5 mortality surveillance system in Zhejiang from 2012 to 2021. CAMR by sex, residence, and age group for each year was calculated and standardized according to 2020 National Population Census sex- and residence-specific live birth data in China. Poisson regression models were used to estimate the annual average change rate (AACR) of CAMR and to obtain the rate ratio between subgroups after adjusting for sex, residence, and age group when appropriate., Results: From 2012 to 2021, a total of 1753 children died from CAs, and the standardized CAMR declined from 121.2 to 62.6 per 100,000 live births with an AACR of -9% (95% CI -10.7% to -7.2%; P<.001). The declining trend was also observed in female and male children, urban and rural children, and neonates and older infants, and the AACRs were -9.7%, -8.5%, -8.5%, -9.2%, -12%, and -6.3%, respectively (all P<.001). However, no significant reduction was observed in children aged 1-4 years (P=.22). Generally, the CAMR rate ratios for male versus female children, rural versus urban children, older infants versus neonates, and older children versus neonates were 1.18 (95% CI 1.08-1.30; P<.001), 1.20 (95% CI 1.08-1.32; P=.001), 0.66 (95% CI 0.59-0.73; P<.001), and 0.20 (95% CI 0.17-0.24; P<.001), respectively. Among all broad CA groups, circulatory system malformations, mainly deaths caused by congenital heart diseases, accounted for 49.4% (866/1753) of deaths and ranked first across all years, although it declined yearly with an AACR of -9.8% (P<.001). Deaths due to chromosomal abnormalities tended to grow in recent years, although the AACR was not significant (P=.90)., Conclusions: CAMR reduced annually, with cardiovascular malformations ranking first across all years in Zhejiang, China. Future research and practices should focus more on the prevention, early detection, long-term management of CAs and comprehensive support for families with children with CAs to improve their survival chances., (©Wen-Hong Dong, Jun-Xia Guo, Lei Wang, Shuang-Shuang Zheng, Bing-Quan Zhu, Jie Shao. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 03.06.2024.)

The volatile oil of Chuanxiong Rhizoma(CX) is known as an effective fraction. In order to seek a suitable method for processing CX and its decoction pieces, this study selected 16 volatile components as indices to investigate how different processing methods such as washing/without washing, sun-drying, baking, oven-drying and far-infrared drying at different temperatures affected the quality of CX and its decoction pieces(fresh CX was partially dried, cut into pieces, and then dried) by headspace gas chromatography-mass spectrometry(GC-MS), cluster analysis, principal component analysis and comprehensive weighted scoring. The results showed that the rapid washing before processing did not deteriorate the volatile components of CX. Considering the practical condition of production area, oven-drying was believed to be more suitable than sun-drying, baking, and far-infrared drying. The CX decoction pieces with a thickness of 0.3-0.4 cm were recommended to be oven-dried at 50 ℃. The integrated processing(partial drying, cutting into pieces, and drying) did not cause a significant loss of volatile components. For the fresh CX, the oven-drying at 60 ℃ is preferred. The temperature should not exceed 60 ℃, and drying below 60 ℃ will prolong the processing time, which will produce an unfavorable effect on volatile components. This study has provided the scientific evidence for field processing of CX, which is conducive to realizing the normalization and standardization of CX processing in the production area and stabilizing the quality of CX and its decoction pieces.

Objective: The new varieties of Salvia miltiorrhiza were bred by the variety comparison test., Methods: Taking these varieties of CDS1,CDS2,CDS3,CDS4,CDS5 as the test varieties, which bred by system seletion from abundant germplasm resources,the conventional variety as the control, the test were arranged in Ximeishan, Linjiagou, Shiya, Hexing Village of Zhongjiang county in 2010 and 2011. And the new varieties from the growth cycle,line of characters,yield, quality and other aspects of Salvia miltiorrhiza were evaluated., Results: CDS2 had the highest yield which was significantly higher than the control group. The growth period were 250 ~ 270 days,the seed germination were early,and the plants were taller. And the medicine merchandise traits were better, the salvianolic acid and the tanshinone were significantly higher. CDS2 was named as the "Zhongdan 1"by crop variety Committee of Sichuan province in2012,which identified by technology field in 2011., Conclusion: "Zhongdan 1"is a new variety through the certification authority validation,which has a great popularization value in the production.

Objective: To explore the method to reduce the Cd content in Ligusticum chuanxiong, and to offer the reference for planting Ligusticum chuanxiong with low Cd content., Methods: A field experiment was carried out to improve the acidic Cd-contaminated soils by different quicklime application, and the effect of quicklime on the percentage of active-state Cd in soil and Cd content in Ligusticum chuanxiong was examined., Results: Quicklime could reduce the percentage of active-state Cd in soil by increase the acid soil pH value,and as a result, significantly reduce Cd content in Ligusticum chuanxiong. A highly significant negative correlation was found be- tween the Cd content in Ligusticum chuanxiong and quicklime application rate(P =0. 008). Compared with the blank group, Cd content in Ligusticum chuanxiong was reduced by 27. 66%, 24. 87% and 46. 20%, with 750, 1 125 and 1 500 kg/hm2 quicklime application, respectively; while with 1 500 kg/hm2 quicklime application, the soil pH value increased significantly and kept steadily, and the percentage of active-state Cd in soil showed a regular trend which was decreased firstly and increased subsequently., Conclusion: Cd content in Ligusticum chuanxiong can be reduced significantly by quicklime application,and the effect of high application of quicklime on Cd content in Ligusticum chuanxiong, soil pH values and percentage of active-state Cd in soil is more effective and steady.

Objective: Iris tectorum new varieties of CSG1, CSG2, CSG4, CSG5, CSG6, CSG7, CSG8 and CSG9 were bred by system selection from abundant germplasm resources., Methods: Taking conventional variety as the control, comparison test for these new varieties was arranged in Shuangliu, Zhongjiang, Maoxian, Renshou and Anxian in Sichuan. Plot yields were measured after harvesting, yields per mu were calculated and the data were analyzed with DPS 9.50 software., Results: CSG1 had the highest yield which was significantly higher than the control and other varieties. This new variety had passed through the field identification by Sichuan Provincial Crop Variety Approval Committee in 2013 and would be applied for approval in 2014., Conclusion: CSG1 is the first batch of Iris tectorum new variety identified by domestic authority and has great promotion potential.

A palladium-catalyzed asymmetric O-H insertion reaction was developed. Palladium complexes with chiral spiro bisoxazoline ligands promoted the insertion of α-aryl-α-diazoacetates into the O-H bond of phenols with high yield and excellent enantioselectivity under mild reaction conditions. This palladium-catalyzed asymmetric O-H insertion reaction provided an efficient and highly enantioselective method for the preparation of synthetically useful optically active α-aryl-α-aryloxyacetates., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Oxidative stress has been proven to be involved in cisplatin (DDP)-induced toxicity. The aim of the present study was to investigate a possible protective role of grape seed proanthocyanidin extract (GSPE) in DDP-induced spermiotoxicity. GSPE at 200 mg kg(-1) d(-1) and 400 mg kg(-1) d(-1) was orally administered for 15 consecutive days, starting 10 days before a single intraperitoneal dose of DDP (7 mg kg(-1)). Results revealed that testicular and epididymal weight, epididymal sperm count, motility and morphology, the activities of GSH-Px and SOD, and GSH levels were significantly decreased whereas the level of MDA was significantly increased in the DDP group rats. GSPE treatment significantly attenuated the harmful effects of DDP-induced lipid peroxidation, oxidative stress, loss of genital organ weight, as well as function of reproductive organs. These changes were restored to near normal levels by GSPE at 400 mg kg(-1) d(-1). In conclusion, GSPE has dose dependent protective effects against DDP-induced rat testicular toxicity.

Objective: To explore the relation of asbestosis to human 8-oxoguanine DNA glycosidase (hOGG1) genotype and DNA damage, the investigation of hOGG1 polymorphism distribution and DNA strand breakages in peripheral lymphocytes was carried on in occupational population., Methods: A total 101 asbestos-exposed workers and 141 controls were investigated. The DNA damage level was obtained by single cell gel electrophoresis (SCGE) and hOGG1 Ser326Cys polymorphism by PCR-RELP., Results: (1) A significant increase in the exposed group was observed in comet scores at basal (34.8 +/- 16.8), H2O2-induced (136.7 +/- 36.0) and 4 hours after repair (51.0 +/- 18.7) as compared with the control group (P < 0.01). And the scores in H2O2-induced (147.0 +/- 30.8) and 4 hours after repair (56.9 +/- 21.4) were significantly higher in asbestosis workers than in non-asbestosis ones (125.7 +/- 38.2 and 44.9 +/- 15.4, P < 0.01). (2) There was no differences of the genotype distribution between the asbestos group and the control group (chi(2) = 0.22, P = 0.89). A significant difference in the distribution of this polymorphism (Ser/Ser, Ser/Cys, Cys/Cys) between asbestosis group (25.5%, 51.0%, 23.5%) and the non-asbestosis group (48.0%, 36.0%, 16.0%) was observed (chi(2) = 6.023, P < 0.05). The comet scores at H2O2-induced and 4 hours after repair were higher in asbestosis subjects than in non-asbestosis ones (P < 0.05). (3) After adjusting ages, sex, smoking and drinking status, the odds ratios of the Cys allele for asbestosis were 0.66 (95% CI = 0.38 - 1.13) in the exposed subjects., Conclusion: The results suggested that the asbestos occupational exposure might induce DNA damage and the augment on susceptivity of H2O2 oxidation and the fall of the capacity of repairing DNA damage might be one of the mechanisms to induce asbestosis among subjects with the Cys allele.

Aim: Observations on medullary ischemia region, the morphology of neurons and changes of respiration and blood pressure were made, in order to give evidences on how medullary ischemia affects respiration and circulation and give some advices on how to protect from it., Methods: Using cats as the experimental animals, the different parts of the basilar artery trunk were ligated. The changes in the density of blood vessels, the morphology of neurons in the brainstem, the electromyogram (EMG) of the diaphragm and the blood pressure of the femoral artery were investigated., Results: The density of blood vessels notably decreased in the medulla after ligating the basilar artery trunk. The ischemic range induced by ligation of the different parts of the basilar artery trunk overlapped, mainly locating in the medulla rostral to the obex. The soma were swelled and the Nissl bodies decreased in some of neurons in the ischemic region of medulla. The duration of inspiration (T1) and expiration (TE) shortened, respiratory frequency (RF) increased, and mean blood pressure (MBP) decreased in the experimental groups (P < 0.05)., Conclusion: There is an obvious overlap of the areas in which blood supplied by different parts of the basilar artery trunk. Medullary ischemia can involve in changes of respiration and blood pressure. The ischemic damage of neurons in the medulla might be the structural basis of the changes in the respiratory and circulatory functions.