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Objective In view of the high vehicle interior noise problem when running on curved lines, it is necessary to carry out in-depth research on its influencing factors. Method Roughness test and analysis of the wheel-rail surface of the tested vehicles in the track straight and curved sections are carried out. At the same time, the corresponding vehicle bogie area noise and vehicle interior noise at the curved track position before and after rail grinding are collected. Result & Conclusion The study reveals that the wheel roughness exceeds the standard ISO 3095:2013 Acoustics—Railway applications—Measurement of noise emitted by railbound vehicles by approximately 3 dB (A) in certain wavelength ranges, while the roughness of the inner rail of the curved section exceeds by more than 20 dB (A), the rail roughness of the straight section could meet the standard. After grinding, the bogie area noise and vehicle interior noise are significantly reduced. In addition, rail top friction adjustment devices are installed in two S-curve sections with a radius of 300 m. Research results of the comparative tests indicates that the device improves the lubrication conditions between the wheel and rail surfaces when passing the curve, reduces the wheel-rail vibration noise. The vehicle interior noise is also reduced to a certain extent by 3 dB(A) at the second curve. Therefore, in the small curve position of the track, the comprehensive strategy of rail grinding and wheel-rail lubrication state improving can reduce the vehicle interior noise when passing curves.

Inertia friction welding (IFW) is a robust joining technique, particularly for hybrid structures composed of similar or dissimilar alloys. The highly transient thermal responses during friction heating produce variations in heat generation and temperature distribution, which are crucial for designing and controlling the IFW process. This study establishes a finite element (FE) model of the IFW process for dissimilar superalloys and investigates the transition of the interfacial friction regime and its impact on the transient thermal responses. The in-process state variables, including the frictional stress and heat flux, along with their spatial distributions at the welding interface, are obtained through FE simulations. The predicted results indicate that the transient transition of the friction regime produces two Coulomb friction zones accompanied by a shear friction zone. To capture the transient evolution of the friction regime, a novel phenomenological formula is developed. This model accurately predicts the shrinkage and disappearance of the two Coulomb friction zones and the enhancement of the shear friction zone from the initial 0.42 R0–0.87 R0 (where R0 is the workpiece radius) to the entire interface during the IFW process. The variations in interfacial heat flux, frictional stress, and temperature caused by the transition of the friction regime are comprehensively analyzed. Our results reveal that the transition from the Coulomb friction regime to shear friction regime at the interface is beneficial for temperature homogenization at the welding interface. The FE simulation results are validated against published experimental measurements, which confirms the accuracy and reliability of the FE model.

Abstract Background Severe COVID-19 disease is typically associated with an urgent need for supplemental oxygen therapy that may be successfully delivered through conventional methods or require invasive mechanical ventilation. Early prediction of the need for invasive mechanical ventilation could significantly improve outcomes of COVID-19 patients. Plasma levels of D-dimer and a number of inflammatory markers as well as values of complete blood counts, all measured in the first two days of hospital admission of COVID-19 patients, were evaluated for their significance as predictors of the eventual need for invasive mechanical ventilation support as well as their values as predictors of post-ventilation morbidly and mortality. Methods This retrospective cohort study was conducted at a single center and included data pertaining to 200 patients with previously confirmed moderate to severe COVID-19 disease in the period between May 2021 and the end of December 2022. Data were retrieved from medical records for further analysis. Results The mean (SD) age of patients stood at 59 (14) years of age, and with a majority of patients being male (77%). About 18% of cases, all of significantly older age, had been connected to invasive mechanical ventilation (IMV). Total leucocytic count (TLC), as well as levels of urea, creatinine, D-dimer, ferritin, and CRP in IMV patients were significantly higher than non-ventilated patients (p

In order to realize the intelligent prediction of valve inlet water temperature of a voltage sourced converter-high voltage direct current (VSC-HVDC) valve cooling system, a prediction model of inlet water temperature of VSC-HVDC based on a hybrid model of the random forest (RF) and bi-directional long short-term memory (BiLSTM) is proposed, and the cooling capacity of the cooling system is evaluated on the basis of the proposed prediction model. Firstly, a RF algorithm is used to analyze the importance of high-dimensional feature sets, which consist of all the monitoring variables of the valve cooling system. Then the important characteristic parameters affecting the inlet water temperature are filtered out to form an input feature vector with the historical inlet water temperature. Secondly, the feature vector is input to the developed BiLSTM prediction model to train the model for accurately predicting inlet valve water temperature and quantitatively evaluating the cooling capacity. Finally, a VSC-HVDC converter station in Guangdong power grid is taken as an example to verify the effectiveness and superiority of the proposed method. Simulation results indicate that the accuracy of the proposed hybrid model based on RF-BiLSTM is higher than that based on BiLSTM model, RF model, support vector machine (SVM) model and auto-regressive and moving average (ARMA) model. Moreover, the cooling capacity is evaluated quantitatively and accurately. Analysis results show that the cooling margin of this converter station is up to 98%, which indicates that there is a problem of overcooling and energy waste. The evaluation result of the cooling capacity is well consistent with the field operation result of the converter station, which confirms the effectiveness and the accuracy of the proposed method.

The activation of the monocyte-macrophage system and the damage to the renal and pancreatic tissue are common complications in patients with diabetes induced by hyper-glycemia. This study aimed to evaluate the effect and mechanism of butyrate (NaB), a metabolite of intestinal flora, on inhibiting the inflammatory response of human monocyte-macrophages (THP-1 cells) induced by high glucose and the damage of pancreatic and renal tissue in diabetic mice. The results showed that high concentration glucose significantly up-regulated the expressions of IL-1β, TNF-α, and NLRP3 in THP-1 cells and mouse spleen, and that NaB could inhibit the overexpression of those genes. The abundance of Beclin-1, LC3B and reactive oxygen species (ROS) in THP-1 cells is increased due to the high glucose concentration, and NaB can inhibit the genes responsible for upregulating the expression. In diabetic mice, vacuolar degeneration of renal tubules was observed. Then we observed that some of the epithelial cells of the renal tubules were exfoliated and some formed tubules. NaB could alleviate these pathological lesions, but NaB cannot alleviate pancreatic injury. Our results indicated that NaB could be used for the prevention and adjuvant treatment of diabetic kidney injury.

BACKGROUND Rare, dispersed, and rare earth elements are important strategic resources because of their special performance and function. At the same time, because of its unique geochemical properties, it is of great significance in the study of paleoclimate, paleo-water and paleo-sedimentary environment, and sediment sources. Previous studies have found that Ga in the Ningdong Coalfield is slightly enriched and rare earth element content is low. OBJECTIVES To explore the possibility of enrichment and mineralization of rare, dispersed, and rare earth elements in the coal series of the Yan'an Formation of Middle Jurassic in the Ningdong Coalfield, and discuss the characteristics of paleosedimentary environment and properties of provenance rock. METHODS Systematic sampling was carried out in the core of boreholes from the Lingwu and Jijiajing mining areas of the Ningdong Coalfield. ICP-MS was used to determine the content of rare, dispersed, and rare earth elements in mudstone, sandstone and top (bottom) plate of the Yan'an Formation. RESULTS The overall content of rare, dispersed, and rare earth elements in the Yan'an Formation of the Ningdong Coalfield is low, which do not meet the requirements of the industrial indicators of the deposit and cannot be exploited comprehensively. The highest content of Ga is 29.40μg/g, which is close to the lowest industrial grade of 30.00μg/g. Compared with the average content of elements in world coal, rare elements Li, Nb, Ta, Rb, Cs, Zr and dispersed elements Ga, In, Sc, Hf are slightly enriched or enriched. The distribution of rare earth elements shows LREY type, and significant negative anomaly of Eu. CONCLUSIONS Rb, Sr and REY indicate the humidity of paleoclimate conditions, Li, Sr and Ga represent the freshwater deposition environment, and Ce, Ce/La reflect the anoxic reducing environment. The REY content is not affected by diagenesis and can be used to discriminate the original sediment source.

The ASP30 powder metallurgy (PM) high speed steels strengthened by TiCN were fabricated by powder metallurgy process, the effects of TiCN and rotary awaging deformation on the mechanical properties, microstructure, and tribological behaviors of the ASP30 steels were investigated. The results show that, adding TiCN with the mass fraction of 5% can effectively improve the wear resistance of ASP30. After the quenching-tempering treatment, the bending strength of ASP30+5%TiCN with the 56% swaging deformation is 4084.99 N·mm‒2, and the impact toughness is 14.55 J·cm‒2. The strength and toughness of the ASP30 steels after swaging are effectively improved. After the repeated radial swaging deformation, the TiCN phases are obviously broken and distribute as the dispersion particles. Besides, the rotary swaging can promote the formation of TiCN core-rim structure and improve the wettability and bonding ability between the hard phase and the matrix, inhibiting the generation of cracks between the hard phase and the matrix during grinding.

Abstract The total variation (TV) regularization with $$l_1$$ l 1 fidelity is a popular method to restore the image contaminated by salt and pepper noise, but it often suffers from limited performance in edge-preserving. To solve this problem, we propose a nonconvex $$\hbox{TV}_q-l_1$$ TV q - l 1 regularization model in this paper, which utilizes a nonconvex $$l_q$$ l q -norm $$(0

Full-space metasurfaces demonstrate powerful abilities in manipulating electromagnetic (EM) waves, but most of them are usually single band. Here, a multiband bidirectional digital coding metasurface is proposed for multiple tasks, which can achieve completely different functions in up to six frequency bands when the EM waves are incident from the front and back of the metasurface. As a proof-of-concept, we design and fabricate a dual-band full-space metasurface with integrated functions of reflection, transmission, holographic imaging, and vortex-beam forming, and a six-band full-space metasurface with completely independent holographic imaging functions at different frequency bands. Simulated and measured results are in good agreements with the theoretical predictions, verifying the good performance of the proposed multitask bidirectional digital coding metasurface.

Abstract Background 5-Fluorouracil (5-FU) is a used chemotherapy drug for cancer, and its main side effect is intestinal mucositis which causes chemotherapy to fail. It was known that short-chain fatty acids (SCFAs) can inhibit immune cell release of various proinflammatory factors and inhibit excessive intestinal inflammation. However, the inhibitory effect of SCFAs on 5-FU-induced intestinal mucositis is still unclear. Results To simulate the effects of SCFAs on immune and intestinal epithelial cells, the cells (THP-1 cells and Caco-2 cells) were pretreated with sodium acetate (NaAc), sodium propionate (NaPc) and sodium butyrate (NaB), then inflammation was induced by 5-FU. The expressions of reactive oxygen species (ROS), Beclin-1, LC3-II, NF-κB p65, NLRP3 inflammasome, proinflammatory/anti-inflammatory cytokines and mucosal tight junction proteins were determined. In our results, the three SCFAs could inhibit ROS expressions, NLRP3, Caspase-1, IL-1β, IL-6, IL-18, Beclin-1 and LC3-II, when induced by 5-FU. In a 5-FU-induced chemoentermuctis mouse model, Lactobacillus rhamnoides can increase the concentrations of three SCFAs in faeces and increase the concentrations of IL-1β, IL-6 and IgA in serum, and decrease the expressions of NLRP3 and IL-17 in spleen cells. The expressions of ZO-1 and Occludin in intestinal mucosa were significantly increased. Conclusions These results indicated that the three SCFAs can effectively suppress the inflammation of THP-1 cells and Caco-2 cells and maintain tight junction integrity in intestinal mucosal epithelial cells.

BackgroundTumor necrosis factor (TNF) is an inflammatory cytokine that can coordinate tissue homeostasis by co-regulating the production of cytokines, cell survival, or death. It widely expresses in various tumor tissues and correlates with the malignant clinical features of patients. As an important inflammatory factor, the role of TNFα is involved in all steps of tumorigenesis and development, including cell transformation, survival, proliferation, invasion and metastasis. Recent research has showed that long non-coding RNAs (lncRNAs), defined as RNA transcripts >200 nucleotides that do not encode a protein, influence numerous cellular processes. However, little is known about the genomic profile of TNF pathway related-lncRNAs in GBM. This study investigated the molecular mechanism of TNF related-lncRNAs and their immune characteristics in glioblastoma multiforme (GBM) patients.MethodsTo identify TNF associations in GBM patients, we performed bioinformatics analysis of public databases - The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA). The ConsensusClusterPlus, CIBERSORT, Estimate, GSVA and TIDE and first-order bias correlation and so on approaches were conducted to comprehensively characterize and compare differences among TNF-related subtypes.ResultsBased on the comprehensive analysis of TNF-related lncRNAs expression profiles, we constructed six TNF-related lncRNAs (C1RL-AS1, LINC00968, MIR155HG, CPB2-AS1, LINC00906, and WDR11-AS1) risk signature to determine the role of TNF-related lncRNAs in GBM. This signature could divide GBM patients into subtypes with distinct clinical and immune characteristics and prognoses. We identified three molecular subtypes (C1, C2, and C3), with C2 showing the best prognosis; otherwise, C3 showing the worst prognosis. Moreover, we assessed the prognostic value, immune infiltration, immune checkpoints, chemokines cytokines and enrichment analysis of this signature in GBM. The TNF-related lncRNA signature was tightly associated with the regulation of tumor immune therapy and could serve as an independent prognostic biomarker in GBM.ConclusionThis analysis provides a comprehensive understanding of the role of TNF-related characters, which may improve the clinical outcome of GBM patients.

Magnesium alloy has the advantages of low density, good damping and noise reduction and good electrical conductivity. It is the lightest metal structural material in applications. However, they are easily corroded due to the low potential of magnesium alloy electrodes, which limits their wide application in industry. At present, surface coating protection technology is one of the most effective methods to improve the corrosion resistance of magnesium alloys. Graphene oxide (GO) has excellent thermal, mechanical and barrier properties, and has broad application prospects in metal protection. GO-based composite coatings can provide a good physical barrier to corrosive media and have become one of the candidate materials for anti-corrosion coatings. In this article, the solutions were proposed for the limitations of single-component GO nanosheets, such as agglomeration and poor compatibility. The preparation methods, types and corrosion protection research progress of GO composite coatings were mainly summarized and its protection mechanism was analyzed in depth. Finally, the future development trend of GO application of magnesium alloy surface corrosion protection coating were prospected. The preparation methods and types of GO composite coatings on magnesium alloys were mainly described. The research progress and corrosion protection mechanism of GO coating on magnesium alloy were summarized.

The welded joint of a dissimilar titanium alloy was obtained via inertial friction welding technology. The characteristics of the bonding interface and the microstructure of the welded joint were investigated via optical microscopy, scanning electron microscopy and electron backscattered diffraction. The results show that fine, equiaxed grains and interdiffusion bands of the elements Mo and Sn were formed in the weld zone under the high temperature and plastic deformation of the inertial friction welding. The weld zone and thermo-mechanically affected zone formed ⟨1¯21¯0⟩ α texture and ⟨111⟩ β texture, respectively.

BACKGROUND Tungsten molybdenum ores are strategic mineral resources. China is a large producer and consumer of tungsten and molybdenum ore. Accurate and efficient analysis of tungsten and molybdenum and its associated beneficial and harmful elements is of great significance for the evaluation and comprehensive utilization of tungsten and molybdenum ore deposits. Acid dissolution and alkali fusion are the general digestion methods in tungsten molybdenum ore analysis. However, the acid solution method cannot be used to overcome the hydrolysis problem when treating samples with high content of tungsten and molybdenum, whereas the alkali fusion method such as sodium peroxide and sodium hydroxide usually introduces a large content of alkali metals, so the determination of potassium and sodium cannot be finished. OBJECTIVES To find an efficient method for the determination of tungsten, molybdenum and 11 other elements in tungsten molybdenum ore. METHODS Lithium metaborate melting-tartaric acid ultrasonic leaching and inductively coupled plasma-optical emission spectrometry (ICP-OES) was used for the simultaneous determination of tungsten, molybdenum, copper, lead, zinc, aluminum, iron, calcium, magnesium, titanium, manganese, potassium and sodium in tungsten-molybdenum ore. The sample was completely digested by lithium metaborate fusion. No other elements were introduced except for B and Li. Tartaric acid was used to inhibit the hydrolysis of tungsten and molybdenum. Ultrasonic leaching speeds up the dissolution of the frit. RESULTS The experiment optimized the analysis spectrum and observation method of each element, compared the amount of flux and instrument conditions to obtain the best conditions, and used the matrix matching method to draw a standard curve to eliminate the influence of the matrix effect. The linear correlation coefficient of the standard curve of each element was greater than 0.9990, the detection limit of the method was 1.34-46.2μg/g, the relative error of measured results was 0.14%-8.7%, the relative standard deviation (RSD, n=10) of the measured results was 1.4%-7.6%. CONCLUSIONS This method can accurately and efficiently complete the simultaneous determination of multiple elements in tungsten and molybdenum ore samples.

ObjectiveThis study investigates whether people with sleep disorders following traumatic brain injury exhibit altered intestinal flora. The changes may allow us to gain a better understanding of the role of intestinal flora in patients with sleep disorders after traumatic brain injury, which may give us insights into curing the sleep disorder after traumatic brain injury (TBI).MethodWe analyzed the intestinal microbial colony structure in the feces of the 28 patients in the normal sleep group and the sleep disorder group by 16SrDNAsequencing technology. The bioinformatics method was used to analyze the intestinal flora change in the v3-v4 region of patients with biorhythm disorder and to observe the difference between the two groups.ResultsGroup grouping comparison and analysis of the evolutionary cladistic map showed the intestinal flora of patients with normal sleep after TBI was mainly Bacilli and Lactobacillales, while that of patients with sleep disorders was mainly Lachnospiraceae and Bacteroidales. The histogram of group value distribution by grouping comparison and analysis showed that Lachnospiraceae, Bacteroidales, Bacteroidia, and Bacteroidetes were dominant in the sleep disorder group. A relative abundance map of species with significant differences by group grouping comparison showed the main manifestations of intestinal flora are Firmicutes, Bacilli, Lactobacillales, Streptococcaceae, and Bacteroidetes. The normal sleep group was dominated by Bacilli, Lactobacillales, Streptococcus, and Veillonella, while in the sleep disorder group, Lachnospiraceae, Bacteroidales, Bacteroidia, and Bacteroidetes were the main species. It was found that there were also significant differences in intestinal flora abundance between the two groups after TBI. After statistics processing, it was compared with the normal sleep group, Lactobacillus, Streptococcus, Oribacterium and Rothia, Actinomyces, Streptophyta, TM7-3 bacteria, and Serratia, showing a significant reduction in the sleep disorder group (P < 0.05). However, Odoribacter, Lachnospiraceae, and Bilophila increased significantly (P < 0.05).ConclusionThe sleep disorders of patients after TBI can be closely related to intestinal flora disturbance, and its internal mechanism needs further study. Intestinal flora has the potential to be a new therapeutic target.

Aims: To explore the population pharmacokinetics of colistin sulfate and to optimize the dosing strategy for critically ill patients.Methods: The study enrolled critically ill adult patients who received colistin sulfate intravenously for more than 72 h with at least one measurement of plasma concentration. Colistin concentrations in plasma or urine samples were measured by ultraperformance liquid chromatography tandem mass spectrometry (LC-MS/MS). The population pharmacokinetics (PPK) model for colistin sulfate was developed using the Phoenix NLME program. Monte Carlo simulation was conducted to evaluate the probability of target attainment (PTA) for optimizing dosing regimens.Results: A total of 98 plasma concentrations from 20 patients were recorded for PPK modeling. The data were adequately described by a two-compartment model with linear elimination. During modeling, creatinine clearance (CrCL) and alanine aminotransferase (ALT) were identified as covariates of the clearance (CL) and volume of peripheral compartment distribution (V2), respectively. In addition, colistin sulfate was predominantly cleared by the nonrenal pathway with a median urinary recovery of 10.05% with large inter-individual variability. Monte Carlo simulations revealed a greater creatinine clearance associated with a higher risk of sub-therapeutic exposure to colistin sulfate. The target PTA (≥90%) of dosage regimens recommended by the label sheet was achievable only in patients infected by pathogens with MIC ≤0.5 mg/L or with renal impairments.Conclusion: Our study showed that the dose of intravenous colistin sulfate was best adjusted by CrCL and ALT. Importantly, the recommended dosing regimen of 1.0–1.5 million units daily was insufficient for patients with normal renal functions (CrCL ≥80 ml/min) or those infected by pathogens with MIC ≥1.0 mg/L. The dosage of colistin sulfate should be adjusted according to renal function and drug exposure.

Emergent magnetic phenomena at interfaces represent a frontier in materials science, pivotal for advancing technologies in spintronics and magnetic storage. In this Letter, we utilize a suite of advanced X-ray spectroscopic and scattering techniques to investigate emergent interfacial ferromagnetism in oxide superlattices composed of antiferromagnetic CaMnO3 and paramagnetic CaRuO3. Our findings demonstrate that ferromagnetism exhibits an asymmetric profile and may extend beyond the interfacial layer into multiple unit cells of CaMnO3. Complementary density functional calculations reveal that the interfacial ferromagnetism is driven by the double exchange mechanism, facilitated by charge transfer from Ru to Mn ions. Additionally, defect chemistry, particularly the presence of oxygen vacancies, can play a crucial role in modifying the magnetic moments at the interface, possibly leading to the observed asymmetry between the top and bottom CaMnO3 interfacial magnetic layers. Our findings underscore the potential of manipulating interfacial ferromagnetism through point defect engineering.

Gallium nitride high electron mobility transistor (GaN HEMT) is liable to gate false turn-on problem when the gate crosstalk voltage exceeds its threshold voltage in the widely adopted phase-leg topology due to its low threshold voltage and high switching speed. Without considering the gate loop stray inductance, gate internal resistance, nonlinearity of parasitic capacitances and power loop stray parameters, traditional false turn-on analytical method is insufficient to support accurate analysis. And it has been found that GaN HEMT gate-source parasitic capacitance $C_{\mathrm {gs}}$ previously assumed constant is otherwise highly nonlinear and has strong impacts on the gate crosstalk voltage. This paper has measured $C_{\mathrm {gs}}$ by vector network analyzer and constructed an accurate nonlinear model of $C_{\mathrm {gs}}$ , based on which an accurate GaN HEMT behavior model is further fulfilled. The accuracy of the proposed behavior model has been verified by large amounts of experiment results. The proposed GaN HEMT model is used to accurately calculate gate crosstalk voltage and switching losses. Besides, false turn-on induced extra loss has been calculated and is adopted as a criterion to evaluate the severity of false turn-on and optimal design method for false turn-on suppression has been detailed further.

Abstract The current research of titanium alloy on friction welding process in the field of aero-engines mainly focuses on the linear friction welding. Compared to the linear friction welding, inertial friction welding of titanium alloy still has important application position in the welding of aero-engine rotating assembly. However, up to now, few reports on inertial friction welding of titanium alloy are found. In this paper, the near-alpha TA19 titanium alloy welded joint was successfully obtained by inertial friction welding (IFW) process. The microstructures and mechanical properties were investigated systematically. Results showed that the refined grains within 15‒20 μm and weak texture were found in the weld zone due to dynamic recrystallization caused by high temperature and plastic deformation. The weld zone consisted of acicular α′ martensite phase, αp phase and metastable β phase. Most lath-shaped αs and β phase in base metal were transformed into acicular martensite α′ phase and metastable β phase in thermo-mechanically affected zone and heat affected zone. As a result, the microhardness of welded joint gradually decreased from the weld zone to the base metal. Tensile specimens in room temperature and high temperature of 480 °C were all fractured in base metal illustrating that the inertia friction welded TA19 titanium alloy joint owned higher tensile strength compared to the base metal.

BACKGROUND Sepiolite is a widely used fibrous magnesium-rich silicate clay mineral. Sepiolite is mainly composed of silicon and magnesium, with minor aluminum, potassium, sodium and other impurities. Determination of the major element of sepiolite usually adopts the classical chemical analytical method. After the alkali melting treatment, the sample is determined by volumetric method, photometry and atomic absorption spectrometry, which is inefficient and time-consuming. Moreover, potassium and sodium cannot be simultaneously determined. OBJECTIVES To find an efficient method for the determination of seven major elements in sepiolite. METHODS The samples were digested by hydrofluoric acid, nitric acid, and perchloric acid. Contents of major elements such as Al2O3 were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). The dosage of hydrofluoric acid was optimized. The analytical spectral lines were Al 396.153nm, Ti 334.940nm, K 766.490nm, Na 589.592nm, Ca 422.673nm, Mg 285.213nm and Fe 238.204nm, and elements were determined by axial observation. The content of magnesium in sepiolite was high, and there was a certain matrix effect during ICP-OES analysis. A series of high magnesium mixed standard solutions were prepared to match the matrix. RESULTS The linear correlation coefficient of the standard curve of each element was greater than 0.9990, the detection limits of the method were 0.53-3.25μg/g, the relative standard deviations (RSD, n=10) of the measured results were 0.66%-5.65%, and the recoveries of each element were 95.3%-108.5%. CONCLUSIONS Acid dissolution is easy to operate compared with the alkali fusion method. The results are consistent with those obtained by classical chemical analytical methods and thus meet the analytical requirements of sepiolite samples.

BACKGROUND The dissolution of antimony ore by aqua regia is often incomplete and antimony is easy to hydrolyze in the process of extraction, which leads to inaccurate results. Although atomic fluorescence spectrometry has been widely used in the determination of antimony, it is easy to introduce large dilution error for the determination of high-content antimony (>5%) due to the narrow linear range of the instrument. OBJECTIVES To solve the problem of incomplete dissolution of antimony ores and hydrolysis of antimony in the extraction process, and establish a new method with wider linear range for determination of antimony in antimony ores. METHODS Based on inductively coupled plasma-optical emission spectrometry (ICP-OES), the antimony ore was fully dissolved by hydrofluoric acid, nitric acid and hydrochloric acid, and the hydrolysis of antimony was fully inhibited by the complexation of tartaric acid and antimony. RESULTS The results showed that the solution of the mixed hydrofluoric acid, nitric acid and hydrochloric acid can effectively decompose the silicate components in antimony ores, which can make antimony ores dissolve more completely. The determination result of antimony was better than that of aqua regia, and the detection limit was lower (1.10μg/g). The determination result of antimony obtained by the mixed extraction method of tartaric acid and hydrochloric acid was better than that of aqua regia. The precision of the method was 0.11%-1.11%, which was more stable than that of hydrochloric acid or aqua regia. By using an inductively coupled plasma emission spectrometer, a wider linear range can be obtained by optimizing the spectrum of antimony element analysis, therefore realizing the accurate determination of high-content antimony. CONCLUSIONS This method can dissolve antimony ore quickly and effectively, and avoid the hydrolysis of antimony. The method is confirmed by national first grade standard materials, and the result is in agreement with the certified values. This method is suitable for the analysis of 0.7%-40% antimony in antimony ores.

Abstract Traditional weather and climate forecasting is used by many indigenous communities worldwide as a guide in making important decisions that enable them cope and adapt to climate change-induced extreme weather variation. In many pastoral communities in Africa, traditional weather and climate forecasting remains the most accessible and affordable source of weather and climate information. In this study, we used individual interviews and focused group discussions to systematically document indigenous weather and climate forecasting knowledge among Afar pastoralists, with the aim of making such information available, and enhance use of this knowledge in climate change adaptation and explore synergies with modern weather forecasting system. The Afar pastoralists traditionally predict weather and climate variation through the observation of diverse bio-physical entities including livestock, insects, birds, trees and wildlife. No single indicator is taken at face value; weather forecasting is undertaken in a dynamic process where information collected from different sources, including weather information from the modern weather forecasting system, is triangulated to make the safest livelihood decisions. Before any forecasting information is used, it is evaluated through three traditional institutions that collect, share and analyse the information. These institutions include (1) the Edo or range scouting where traditional rangeland scouts are sent on a mission to assess weather and other spatially and temporally variable attributes on rangelands; (2) the Dagu, a traditional secured and reputable network, where weather information is shared among users; and (3) the Adda or the traditional Afar governance system, which analyses traditional weather information before community decisions are made. This first-time systematic documentation of indigenous weather and climate forecasting knowledge among the Afar communities demonstrated the dynamic process of indigenous weather and climate knowledge production, analysis and communication. This shows the value of indigenous knowledge in contemporary pastoral communities, while highlighting synergies with the modern weather and climate knowledge system for co-production of knowledge that serves the objectives of local people.

OBJECTIVES: In the present study, a novel single knot tenorrhaphy was developed by combining the modified Kessler flexor tendon suture (MK) with the loop lock technique. METHODS: A total of 48 porcine flexor digitorum profundus tendons were collected and randomly divided into six groups. The tendons were transversely cut and then repaired using six different techniques, the MK method, double knot Kessler-loop lock flexor tendon suture (DK), and single knot Kessler-loop lock flexor tendon suture (SK), each in combination with the epitendinous suture (P), and the same three techniques without P. Furthermore, by performing the load-to-failure tests, the biomechanical properties and the time taken to complete a repair, for each tenorrhaphy, were assessed. RESULTS: Compared to the MK+P method, DK+P was more improved, thereby enhancing the ultimate tensile strength. The SK+P method, which required fewer knots than DK+P, was easier to perform. Moreover, the SK+P repair increased the force at a 2-mm gap formation, while requiring lesser knots than DK+P. CONCLUSION: As opposed to the traditional MK+P method, the SK+P method was improved and exhibited better biomechanical properties, which may facilitate early mobilization after the repair.