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For solving the problems of poor structural stability and machining difficulties of non-metallic insulating rings in space conductive slip rings, Al2O3 ceramic coatings were deposited on 2A12 aluminum alloy substrate by atmospheric plasma spraying technology to replace non-metallic insulating materials, and the phase composition, microscopic morphology, microhardness, bonding strength, and insulation performance of the coating were studied. Results showed that the main phase of Al2O3 spherical powder prepared by agglomeration sintering of original nanoparticles was α-Al2O3. After spraying, Al2O3 in the coating existed as α phase and γ phase, and the coating bonded well with the substrate, and the porosity of the coating was relatively lower. Moreover, the as-prepared coating had a uniform and dense microstructure, with no obvious macroscopic cracks or large pores inside the coating. Although no sealing treatment was used, the coating still presented high insulation performance in insulation resistance tests with a DC voltage of 1 000 V in atmospheric environments, which could meet the service requirements of space conductive slip ring insulating rings.

Background Test consolidation and total laboratory automation (TLA) were implemented in a core laboratory with a high volume of specimens in a medical center in Taiwan to reduce the costs of laboratory services and improve laboratory workflow and performance. Methods Using a retrospective research approach, 5 stat and 7 routine tests were used to analyze the in-laboratory to report turnaround time (IR-TAT). Mean, SD, medium, 90th percentile, outlier percentage of IR-TAT, full-time equivalents, productivity, tube touch moment (TTM), and financial impact were determined and compared pre- and post-TLA. Results The mean IR-TAT of overall stat chemical tests for inpatient and outpatient were 32.8% and 11.9% reductions, respectively. The productivity of each medical technologist increased by 32.4% per month, and there was a reduction of 5 medical technologists compared with the number required to complete the same tests before consolidation. The TTM of staff per year post-TLA decreased by 74.1% tube touches. Conclusion The efficiency of laboratory services was improved by consolidation to the core laboratory along with TLA implementation coupled with logic rules such as delta-check and autoverification. Effectiveness was improved as measured by an increase in productivity, labor reduction, staff safety, and cost reduction. [ABSTRACT FROM AUTHOR]

Aim: To assess heart rate variability (HRV) as a measure to assess job stress and sleep quality among nurses in the post‐COVID‐19 period. Background: The COVID‐19 pandemic significantly affected nurses, with heightened job stress and impaired sleep quality impacting their well‐being and effectiveness in patient care. HRV could offer insights for supporting strategies in the pandemic aftermath. Design: A quantitative cross‐sectional study. Methods: This study involved 403 clinical nurses recruited from a teaching hospital in Taiwan. Data on job stress, work frustration, sleep quality and HRV were collected and analysed. Results: Among the nurses surveyed during the COVID‐19 pandemic, 72.7% reported poor sleep quality (PSQI = 9.369). Job stress emerged as a strong predictor of work frustration. High stress levels and poor sleep quality were correlated with significantly decreased HRV, indicating a potential physiological impact of stress on the nurses' health and well‐being. Conclusions: HRV is a valuable and cost‐effective measure for monitoring and managing nurses' well‐being in the post‐COVID‐19 era. Targeted interventions can be implemented to support nurses' overall performance and promote their well‐being by identifying those at high risk of job stress and poor sleep quality. Summary statement: What is already known about this topic? The COVID‐19 pandemic significantly impacted medical care capacity, leading to heightened physical and mental distress among frontline nurses. This has resulted in a marked increase in job stress, presenting a significant challenge to occupational health.The substantial changes in the medical environment caused by the pandemic are likely to induce job stress, which, in turn, can detrimentally affect sleep quality. This aspect is crucial, as sleep quality is a key determinant of nurses' ability to deliver optimal medical care to patients. What this paper adds? Job stress significantly impacts nurses' sleep quality and is a key predictor of work frustration, surpassing the sole influence of work frustration.The study highlights a significant link between high stress levels, reduced sleep quality and decreased heart rate variability in nurses. It further reveals that nurses with moderate COVID‐19‐related anxiety show heightened heart rate variability, indicating sympathetic nervous system activation to maintain alertness in emergency medical situations. The implications of this paper: Moderate anxiety as a positive factor: moderate levels of anxiety among nurses can contribute to maintaining alertness, reducing errors and lowering the risk of contracting COVID‐19.HRV as a monitoring and management measure: heart rate variability is a valuable and cost‐effective measure for monitoring and managing the health of nurses in the post‐COVID‐19 era. By identifying nurses with high work stress and poor sleep quality, targeted interventions can be implemented to support their overall performance and promote their well‐being.Targeted interventions for improved well‐being: the implementation of specific interventions aimed at supporting nurses' overall performance and enhancing their well‐being is crucial in maintaining a high standard of patient care. [ABSTRACT FROM AUTHOR]

BACKGROUND At present, the content of Se in soil is mainly determined by atomic fluorescence spectrometry, which has disadvantages such as large usage of acid and relatively complex pretreatment. Determination of high content of Se requires high dilution, which expands the analysis error. OBJECTIVES To establish a method for the determination of Se and other elements in Se-rich soil samples by wavelength dispersive and energy dispersive X-ray fluorescence (WD-ED XRF). METHODS WD-ED XRF was used to determine 17 major and minor elements such as Se in Hubei selenium-rich soil samples with powder pellet. While 10 elements were analyzed by WD-XRF, As, Cu, Rb, Sr, Zr, Ba, Ni were analyzed by ED-XRF, which significantly reduced the measurement time. RESULTS By mixing different certified reference materials in proportion to configure mixed certified reference materials, the problem of insufficient content of the existing Se reference materials in the range of 5-72μg/g was solved. For the determination of high content Se, the relative standard deviation was less than 10%, and the RSD of high content Se sample was less than 0.70%, through the precision and accuracy assessment. CONCLUSIONS The proposed method satisfies the quantitative analysis of soil samples with Se content greater than 3.00μg/g, and provides the quantitative or approximate quantitative analysis results of 16 major and minor elements.

The majority of myxosporean species (Cnidaria: Myxozoa) of the genera Myxobolus (35 species), Henneguya (8 species), and Myxidium (9 species) from freshwater or brackish fish in Japan were recorded more than 30 years ago (accumulatively 81.1% [43/53]). The re-discovery and molecular–genetic characterization of these species is a current research priority. During our myxosporean survey in Japanese freshwater fish, we detected three species that had never been recorded in Japan, but in the Russian Far East (Sakhalin Island, and Maritime Province): Myxobolus tribolodonus sp. n., forming cysts in the gills of Tribolodon sachalinensis (syn. M. marinus sensu Aseeva, 2000; M. marinus sensu Sokolov et Frolova, 2015, recorded from the gills of Pseudaspius (syn. Tribolodon) spp.); Henneguya pungitii Achmerov, 1953, forming cysts in the subcutis of external skin and buccal submucosa of Pungitius sinensis; and Myxidium salvelini Konovalov et Shulman, 1966, in the urinary bladder of Oncorhynchus masou ishikawae. These new isolates were characterized by integrated taxonomic approaches, i.e., myxospore morphology and molecular–genetic characterization of the small subunit ribosomal RNA gene (SSU rDNA). These new isolates were phylogenetically differentiated from any species whose SSU rDNA sequences were deposited in the DNA databases, and concurrently compared with recorded species based on classical morphological criteria. All three species were differentiated from myxosporeans previously recorded in Japan, indicating new distribution records out of the Russian Far East. For reliable species identification, accumulation of at least SSU rDNA sequences of known species worldwide is critically important. [ABSTRACT FROM AUTHOR]

Daily meteorological data from 1981 to 2022 and citrus growth periods data were used in this paper. The daily mean temperature, daily maximum temperature and their duration were selected as indicators of heat stress in citrus to clarify the spatial distribution characteristic and temporal variation trend of heat stress during citrus growth periods. The spatial and temporal differences of heat stress in different growing periods of citrus were compared using a paired t-test. The results show that (1) the average frequency, times and intensity of heat stress during flowering-fruit expanding stage of citrus are 87.73%, 2.23times•y-1 and 5.28d•times -1, respectively. High-value areas are mainly concentrated in the southeast of Jiangxi province. The average frequency, times and intensity of heat stress during the fruit expanding-fruit coloring stage of citrus are 56.43%, 1.15times•y-1 and 2.74d•times -1, respectively. High-value areas are mainly in the northern and central parts of Jiangxi province. (2) The station ratios, times and intensity of heat stress during the flowering-fruit expanding stage of citrus show a decreasing trend, with an average decrease of 0.90 percent points, 0.02 times and 0.06 d•time -1 every 10 years, respectively. The station ratios, times and intensity of heat stress during fruit expanding-fruit coloring stage of citrus show an increasing trend, with an average increase of 6.80 percent points, 0.26times and 0.50d•times -1 every 10 years, respectively. (3) The paired t-test results show that, the frequency, times and intensity of heat stress during flowering-fruit expanding stage of citrus are significantly higher than that during fruit expanding-fruit coloring stage of citrus. However, the climate tendency of times and intensity of heat stress during flowering-fruit expanding stage of citrus are significantly lower than that during fruit expanding-fruit coloring stage of citrus. The flowering-fruit expanding stage of citrus in Jiangxi province is the most frequent period of heat stress. For now, it is necessary to strengthen citrus defenses against heat stress during the flowering-fruit expanding stage. In the future, we should improve the prevention of heat stress in citrus during the fruit expanding-fruit coloring stage. [ABSTRACT FROM AUTHOR]

OBJECTIVES Ion-adsorption type rare earth ore is extremely important in China and rare in the world. It is China's dominant mineral resource. At present, all the rare earth elements in the existing REE reference materials are oxide minerals, not ion-adsorption type, and cannot be exchanged with strong electrolytes. These reference materials cannot be used to monitor the leaching process of ion-adsorption type REE. METHODS The samples were collected from the typical ion-adsorption type REE weathering crust in Jiangxi Province. After being dried and ball-milled to 200 mesh, they were mixed for 1.5h. The contents of rare earth elements in the ionic phase were analyzed to test the homogeneity by ammonium sulfate leaching and inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS Results showed that the F values for the variance test were less than the threshold, which indicated a good homogeneity. The stability of monitoring samples was tested 4 times in two years, and no statistically significant changes were observed, indicating good stability of the samples. An accurate and reliable leaching analytical method was used in 8 technologically significant laboratories to finalize the contents of ionic phase rare earth elements. The determined values of nine monitoring samples were given by statistical calculation, including weighted average value and total uncertainty results which were from uncertainties in certified values, between-bottle homogeneity and long-term stability. These nine monitoring samples have certified values of 15 ionic phase rare earth elements except Sc. CONCLUSIONS The reference materials can be used to monitor the leaching process and provide metrological support for the analysis of rare earth elements in ionic phase during the evaluation and effective utilization of REE mineral resources.

BACKGROUND At present, the major elements in silicate samples are generally determined by X-ray fluorescence spectrometry with fusion sample preparation. Not only can the single element determination results not exceed the limit, but also the percentage sum must meet the requirements of sum quality (99.3%-100.7%). However, for the analysis of mineralized samples, due to the high content of trace elements, it is often not possible to meet the requirements of sum quality. The wavelength and energy dispersive X-ray fluorescence spectrometer are fully utilized. The advantages of the determination can make the analysts to get the information of sample composition as soon as possible, which is of great significance to evaluate the data quality of mineralized samples. OBJECTIVES To develop a method for determination of major elements in mineralized samples. METHODS The wavelength-energy dispersive X-ray fluorescence spectrometer was used to determine the major elements while adding more minor elements to the determination without prolonging the analysis time. The main elements were quantified by wavelength dispersion, while the minor elements were mainly determined by energy dispersion. Under the condition of ensuring the accuracy of the major elements, the measurement conditions were reasonably set and the energy spectrum measurement time was extended. RESULTS The method achieved the measurement of the major elements within 12 minutes using wavelength dispersion, and also provided results of 14 minor elements such as Rb, Sr, Y, Zr, Ba, Cu, Zn and the semi-quantitative results of 10 elements with narrow linear range or low content such as Co, Ge, Pr and Ta. The maximum limit of detection of 24 minor elements was 16.76μg/g. CONCLUSIONS Through the accuracy assessment, the determination results of major elements are consistent with the certified values, and the determination of minor elements with high content also meets the requirements of quantitative analysis. This method makes the analysts to get the information of sample composition quickly, provides a basis for more accurate and reliable data, and effectively solves the determination of major elements in complex mineralized samples.

BACKGROUND The accurate determination of ionic phase rare earths in ion-adsorption rare earths is of great significance for the evaluation of rare earth ore bodies. Ionic phase rare earths are adsorbed on clay minerals in the form of hydroxyl or hydrated hydroxyls and can be exchanged and desorbed with strong electrolytes (Mg2+, NH4+, etc.) into solution. The former used ammonium sulfate as the leachate to achieve the desorption and extraction of rare earth ions in the ion phase, but the solution concentration, leaching process and other aspects of choice, leaching rates (60% to 90%) are different. There is no efficient and uniform leaching method conducive to the accurate determination of ionic phase rare earth elements. OBJECTIVES To establish a high-efficiency leaching process by ammonium sulfate solution and determine the accurate contents of ionic-phase rare earth elements. METHODS The leaching parameters (solid-to-liquid ratio, ammonium sulfate concentration, best sample weight, and soaking time) of rare-earth ions by ammonium sulfate were standardized through comparative experiments, which reduced the loss of ionic phase rare earth during leaching. The leaching rates were from 88% to 98%, and ICP-MS was used to accurately determine the ion phase rare earth component. RESULTS The detection limits are 0.05-5.11 ng/g, and the relative standard deviations (RSDs) are 1.80%-10.01% for volcanic rock, 1.06%-7.27% for metamorphic rock, and 1.72%-7.58% for sedimentary rock. CONCLUSIONS The analytical results of the collaborative laboratory verify the reliability and accuracy of the method. This method is easy to operate and has high analysis efficiency. It provides the base for the establishment of relevant industry standards and national standards.

BACKGROUND The analysis of ore samples by X-ray Fluorescence Spectrometry (XRF) has the advantages of quantitative accuracy, less reagent and good reproducibility. However, due to the lack of rare earth standard materials at present, the accurate quantitative requirements for complex rare earth ore samples cannot be met. BAOBJECTIVES To establish the analysis method for XRF determination of 25 major elements and rare earth elements in rare earth ores and mineralized samples. METHODS The use of artificial standard samples solved the problem of lack of standard materials. The linear ranges of La, Ce and Y were extended by adding high purity rare earth oxides La2O3, CeO2 and Y2O3. A calibration line was produced using artificial standard samples, existing standard materials of rare earth and carbonate. The major elements were calibrated by a theoretical alpha coefficient method, whereas the rare earth elements were calibrated by an empirical coefficient method. Interference correction was used for elements with overlapping spectral lines. RESULTS The relative standard deviations (RSD, n=13) of most major elements were less than 1.5%, whereas the RSDs of rare earth elements were 0.69%-6.94% when their concentrations were above 300 μg/g. CONCLUSIONS The method was evaluated by unknown samples and the sums of major elements, rare earth elements and loss of ignition were 99.41%-100.63%. The method satisfies the first criterion of Geology and Minerals Laboratory Testing Quality Management Standards.

The northward expansion of peanut cultivation in China is limited by the availability of heat resources, and frost poses a significant challenge to peanut planting in Northeast China. Peanut is the 3rd largest crop in Liaoning province, which is an important exporter of peanuts in China. This paper studied the hazard of frost to peanut cultivation from a disaster-causing perspective, which is of great significance for ensuring the area stability and production safety of oil crops in emerging production areas. Based on the daily minimum temperature data of 56 meteorological stations in Liaoning from 1961 to 2020, the number of spring and autumn frost days were identified, as well as the first and last frost dates during the peanut growing season. The risks of spring frost and autumn frost in peanut cultivation were evaluated and the adaptability of current sowing and harvesting periods in reducing the frost risk in Liaoning was assessed. The results showed that the risk of autumn frost increased from southwest to northeast in Liaoning, while the risk of spring frost increased from south to north. The probability of daily frost occurrence exhibited an "S" shape during autumn and an inverse "S" shape during spring. It took approximately two months for the probability to increase from 0% to 100% and vice versa. The safe growth period for peanuts in Northeast China can be defined as the time between the corresponding date of the sowing lower limit temperature and the date of first frost. Autumn frost has a greater impact on peanut cultivation in Liaoning compared to spring frost. To avoid autumn freezing damage in the highest risk areas such as Fuxin city, the north-central part of Shenyang city and Tieling city, which are the main peanut-producing regions in Liaoning, it is necessary to postpone the harvesting date. While spring freezing damage in most major peanut-producing regions in Liaoning can be avoided by postponing the sowing date, the impact on the harvesting date must also be considered. Frost and wet soil during the autumn harvesting period may pose new challenges. [ABSTRACT FROM AUTHOR]