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The Sn4.7Ag1.7Cu+Ag composite solder/Cu joint was prepared with Sn4.7Ag1.7Cu+Ag composite solder by transient liquid phase (TLP) bonding process.The microstructure of the joints under constant temperature aging was observed by SEM, combined with EDS, the microstructure and properties of the joints under different processes were compared and analyzed. The results show that the service performance of Sn4.7Ag1.7Cu+Ag/Cu joint at high temperature (300℃) is improved with the increase of Ag particle content. When the content of Ag is 25% (mass fraction), the joint does not break after 15 days of service at 83℃ higher than the melting point (217℃) of the base solder, and the tensile strength is 25.74 MPa, which achieves the purpose of low-temperature welding and high-temperature service. Comparing with Sn4.7Ag1.7Cu/Cu joints under reflow welding, with the aging process, the residual Ag particles in Sn4.7Ag1.7Cu+Ag composite solder/Cu joint are dissolved and a large number of Ag3Sn compounds are produced near the interface of the joint. A large number of bulk Ag3Sn compounds can effectively inhibit the diffusion of Sn into the Cu substrate and achieve the purpose of inhibiting the growth of the Cu3Sn layer.Under the condition of service temperature of 200℃, with the aging process, the mechanical properties of the Sn4.7Ag1.7Cu+Ag composite solder/Cu joint first decrease and then increase, then decrease to a stable state, and its mechanical properties are better than that of the Sn4.7Ag1.7Cu/Cu joint.

By adding a longitudinal AC magnetic field and using HS201 pure copper wire as the filler metal, TIG butt joint experiments were conducted on T2 copper and Q235 steel plates, both with the thickness of 2 mm, to study the joint formation, organization and mechanical properties when the magnetic field was added. The results show that the surface of weld zone is formed well after adding magnetic field. The best technological parameter is as follows: when welding current I=95 A, welding speed v=95 mm/min, magnetic field frequency f=25~35 Hz, magnetic field current IE=0.4~0.6 A, the mechanical properties of the joint is good, and the maximum tensile strength is 223.5 MPa, which is 44.5% higher than that without magnetic field. Copper-steel TIG welding joint is mainly divided into steel-HAZ, fusion zone, weld zone and copper-HAZ. After the addition of AC magnetic field, the morphology of ferrite in steel side heat affected zone changes from massive to needle like and lateral strip; the microstructure of weld zone changes from cellular crystal to fine and uniform cellular dendrite; the microstructure of copper-HAZ is obviously refined. After adding magnetic field, the types of phases in the fusion zone and weld zone of the joint have no change, which are composed of (α-Fe)+(ε-Cu); the solute segregation in the fusion zone is improved, and the (α-Fe)+(ε-Cu) particles change from coarse dispersion to fine aggregation; the microstructure of the weld zone is refined and its uniformity is obviously improved, which makes the hardness gradient of fusion zone and weld zone relatively decrease.

The atrophy of the entrance channel in the North Branch of Changjiang Estuary and the sediment supplied by landward tidal flow from the sea to the branch, threaten the sustainable use of the numerous ports and wharves along the riversides. Four different plans of two groups to mitigate the shrinking of the North Branch were proposed and tested. The plans in the first group aimed to expand the entrance channel and the upper section of the North Branch through dredging. The purpose of the plans in the second group was to reduce the landward tidal volume in the lower section of the North Branch to reduce the sediment import from the sea. The effects of these plans were simulated by a 2D computational hydrodynamic model, and the results such as tidal volume at different sections, the portions of tidal volume in different branches, and the high and low tidal levels at the monitoring points, were obtained and compared. After that, one plan from each group was recommended. The measures of the recommended plans have been mostly adopted in the report of Revision of the Comprehensive Regulation and Development Plan of the Changjiang Estuary.

The aim of this study was to explore the characteristics of and preventive management strategies for suicidal inpatients in a general hospital.

Objective To study the anti-caries efficacy of arginine dentifrice on early childhood caries in the rural area of Chengdu city in order to explore better early intervention measures on caries.Methods Two schools in Chengdu rural area were randomly chosen. Subjects were chosen according to the inclusion and exclusion criteria. All subjects were randomly divided into 2 groups, the experimental group used toothpaste containing 1.5% arginine and 1 450 F - ppm, control group used toothpaste containing 1 450 F - ppm, a comprehensive inspection of the dental caries of the 2 groups of subjects were recorded. The results were recorded by EpiData software for data entry, using SPSS 13.0 statistical software analysis data.Results 1 years later, the prevalence, the mean decayed missing filled teeth of deciduous teeth (dmft) of the experimental group was significantly lower than the control group. The number of new dmft score (t = 1.58, P = 0.001), the new decayed missing filled teeth surfaces (dmfs) number (t = 1.16, P = 0.001), The new permanent teeth DMFT number (t = 1.02, P = 0.005), new permanent teeth decay missing filling surface number (t = 1.03, P = 0.002) in the experimental group of deciduous teeth were lower than the control group. And the difference was statistically significant.Conclusion Toothpaste containing 1.5% arginine and 1 450 F - ppm is more significant on children’s dental caries prevention effect compared with the toothpaste containing 1 450 F - ppm only.

Heavy metal elementals can be enriched in soil at mineral products yard, which become a problem of environmental pollution caused by elemental migration, transformation and circulation in underground water. In this experimentation the modified BCR sequential extraction method was applied to the chemical species analysis of Cd, As and Pb. Based on the properties of these three elementals, the chemical species of Cd, As and Pb were divided into four fractions: exchangeable, reducible, oxidizable and residual, and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) were used to measure the content of Cd, As and Pb. Morphological analysis standard reference material GBW 07436 was conducted to verify the accuracy of the three step extraction state. Contents of chemical species of Cd, As and Pb in soil from six mineral products yard were analyzed, including contents of three step extraction state plus the residual and the total contents of the desired metals elements. The recoveries were from 84.54% to 102.88%. The analysis results for actual samples demonstrated the contents of Cd, As and Pb in non-residual fraction were in order as Cd (79.40%-94.94%)>Pb(24.27%-37.73%)>As (22.89%-31.51%), which indicated Cd is easy to enter the biosphere. This method has resolved the problem to extract the chemical species of heavy metal elements in soil from port mineral products yard, and has profound significance to the treatment of contaminated soil.

Heavy metal elementals can be enriched in soil at mineral products yard, which become a problem of environmental pollution caused by elemental migration, transformation and circulation in underground water. In this experimentation the modified BCR sequential extraction method was applied to the chemical species analysis of Cd, As and Pb. Based on the properties of these three elementals, the chemical species of Cd, As and Pb were divided into four fractions: exchangeable, reducible, oxidizable and residual, and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) were used to measure the content of Cd, As and Pb. Morphological analysis standard reference material GBW 07436 was conducted to verify the accuracy of the three step extraction state. Contents of chemical species of Cd, As and Pb in soil from six mineral products yard were analyzed, including contents of three step extraction state plus the residual and the total contents of the desired metals elements. The recoveries were from 84.54% to 102.88%. The analysis results for actual samples demonstrated the contents of Cd, As and Pb in non-residual fraction were in order as Cd (79.40%-94.94%)>Pb(24.27%-37.73%)>As (22.89%-31.51%), which indicated Cd is easy to enter the biosphere. This method has resolved the problem to extract the chemical species of heavy metal elements in soil from port mineral products yard, and has profound significance to the treatment of contaminated soil.

High carbon-chrome iron samples can be decomposed using strong oxidizing acid, mixed acid or by the alkali fusion method under high temperature. These chemical procedures are complex, especially the alkali fusion method, which introduces a large amount of interfering ions such as Na+. Microwave digestion technology is widely used in the pretreatment process of insoluble samples. This pretreatment method combined with Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) has been reported to determine Fe in high carbon-chrome iron. Based on previous studies, a method for the simultaneous determination of silicon, manganese and phosphorus has been established in this study. HNO3 is conducted to digest easy decomposition components in high carbon-chrome iron. HClO4 and HF are then loaded to digest carbides and silicides. Since there is a reduction in the volume of HClO4, the process is stable and safe. Using high carbon-chrome iron standard materials to set up the calibration curve, and Y, In and Bi as internal standard elements, the detection limits of silicon manganese and phosphorus were 0.0017%, 0.0025% and 0.0033%, respectively. Precision and accuracy of this method were verified by using high carbon-chrome iron standard materials of GSB 03-1562—2003, GSB 03-1058—1999 and GSB 03-1059—1999. The results were consistent with the certified values. The relative standard deviations (RSD) are in the range 0.8%-6.0% (n=11), and the relative deviations (RE) are from 0.044% to 0.227%. This method has the advantage of digesting the sample completely, is safe and has a simple operation process and a high degree of accuracy, which can also be used for the determination of several elements in high carbon-chrome iron.

High carbon-chrome iron samples can be decomposed using strong oxidizing acid, mixed acid or by the alkali fusion method under high temperature. These chemical procedures are complex, especially the alkali fusion method, which introduces a large amount of interfering ions such as Na+. Microwave digestion technology is widely used in the pretreatment process of insoluble samples. This pretreatment method combined with Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) has been reported to determine Fe in high carbon-chrome iron. Based on previous studies, a method for the simultaneous determination of silicon, manganese and phosphorus has been established in this study. HNO3 is conducted to digest easy decomposition components in high carbon-chrome iron. HClO4 and HF are then loaded to digest carbides and silicides. Since there is a reduction in the volume of HClO4, the process is stable and safe. Using high carbon-chrome iron standard materials to set up the calibration curve, and Y, In and Bi as internal standard elements, the detection limits of silicon manganese and phosphorus were 0.0017%, 0.0025% and 0.0033%, respectively. Precision and accuracy of this method were verified by using high carbon-chrome iron standard materials of GSB 03-1562—2003, GSB 03-1058—1999 and GSB 03-1059—1999. The results were consistent with the certified values. The relative standard deviations (RSD) are in the range 0.8%-6.0% (n=11), and the relative deviations (RE) are from 0.044% to 0.227%. This method has the advantage of digesting the sample completely, is safe and has a simple operation process and a high degree of accuracy, which can also be used for the determination of several elements in high carbon-chrome iron.

Determination of trace elements in minerals usually requires pre-concentration and separation with many spectral line interferences during measurement. The concentrate ores were calcined at high temperature to remove the C and S. The calcinates were then digested by using the HCl-auqa regia-HF acids system. The D290 anion exchange resin and activated charcoal procedures were conducted to enrich Pt and Pd. The contents of Pt and pd were obtained by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) with internal standard elements of Y, In and Bi and measured isotopes of 105Pd and 195Pt. The absorption property and separation conditions of D290 anion exchange resin to trace Pt and Pd in copper concentrate ores were studied. The enrichment effects of Pt and Pd were above 90%, the recoveries were 92.0% and 96.0%, and the relative standard deviations (RSD, n=6) were smaller than 4%. The detection limits of the method were 0.126 ng/g and 0.105 ng/g for Pt and Pd. The presented method mostly reduced the inferences from other ions to the target elements of Pt and Pd. Moreover, the collision reaction between the internal standard elements and high purity Ar effectively reduced the matrix effect and isobaric interference. Five random geological samples were analyzed by this method in comparison with the method of NiS fire assay ICP-MS and the established method had the advantages of simple pretreatment and high enrichment of Pt and Pd with lower detection limits.

Oviposition site selection is an important aspect of the behavioural ecology of insects. A comparison of the habitats used by a species enhances our understanding of their adaptation to altered environments. We collected data on the oviposition behaviours of Gasterophilus pecorum (Diptera: Gasterophilidae) in its habitat in Kalamaili Nature Reserve (KNR), Xinjiang, China between March and October 2014. We found 91 quadrats were used by G. pecorum for oviposition. Examining 13 ecological factors using the t-test, chi-square test, and principal component analysis showed that G. pecorum’s oviposition habitat was preferentially on slopes with inclinations of 10–30° that were semi-sunny, semi-cloudy slopes, in positions high or low on the slopes, with preferences for total plants lower than 10% and Stipa capillata coverage lower than 10% on the low slopes, but Ceratoides latens coverage on the high and intermediate slopes, when the numbers of plant species and families were lower than five. G. pecorum often selected sites at a distance

Abundance sensitivity is an important technical index of magnetic mass spectrometer, which describes the extent to which the tailing of intense ion peaks at a mass number in its neighborhood affects the weak ion peaks during isotope ratio measurement. It is particularly important in the measurement of isotope ratios containing low abundance nuclides, such as 234U/238U, 236U/238U, and 230Th/232Th. However, the abundance sensitivity of magnetic mass spectrometer is only of the order of 10−6 without taking additional technical measures. To further improve the abundance sensitivity, the techniques of tandem mass spectrometer, such as magnetic-electric, magnetic-magnetic and magnetic-electric-quadrupole tandem mass spectrometer, and retarding filter can be adopted. In fact, while various tandem mass spectrometer techniques can effectively improve the abundance sensitivity of an instrument, they also significantly increase the size, complexity, and cost of instrument, and therefore are not widely used. In contrast, due to its simple structure, small size, and excellent performance, the retarding filter has become a key component for commercial magnetic mass spectrometers to improve abundance sensitivity. Based on the basic principles of ion optics, a retarding filter consisting of five electrodes with a compact structure of only (40×50×50) mm3 was developed by utilizing the ion optics simulation software SIMION8.1. In addition to the function of energy retarding, the retarding filter also has the function of direction retarding, which greatly enhances the filtering capability to scatter ions. To test the ion transmission efficiency and the abundance sensitivity under different voltages, the retarding filter was installed on a domestic double-focusing thermal ionization mass spectrometer (TIMS). The instrument mainly consists of a thermal ionization source, a double focusing mass analyzer consisting of an electrostatic analyzer and a magnetic mass analyzer, a zoom lens, and a multi-collector detector, which can be configured with up to 16 faraday cups, 4 electron multipliers, and 2 retarding filters. The results showed that the abundance sensitivity of the mass spectrometer is successfully improved from

Abstract The coronavirus disease-2019 (COVID-19) pandemic has impaired the quality of life (QoL) for many due to its extensive impacts. However, few studies have addressed the specific impact of COVID-19 on the mental health of adolescents, particularly post-traumatic stress disorder (PTSD). This study considered the impact of COVID-19-related PTSD on the QoL of adolescents in China, the mediating effects of insomnia, and the moderating effects of resilience. Participants included 50,666 adolescents aged 12–18 years selected using a comprehensive sampling method. We performed data collection from January 8th to January 18th, 2023, using the Children’s Revised Impact of Event Scale, Pittsburgh Sleep Quality Index, Ten-item Connor-Davidson Resilience Scale, and Screening for and Promotion of Health-related QoL in Children and Adolescents Questionnaire for data collection. Male adolescents exhibited significantly lower levels of PTSD and insomnia compared to females and scored significantly higher in psychological resilience and overall QoL. Insomnia played a mediating role between PTSD and QoL. Psychological resilience moderated the impact of COVID-19-related stress on adolescents’ QoL through its influence on insomnia. PTSD resulting from the COVID-19 pandemic affects the QoL of adolescents through the presence of insomnia. Psychological resilience plays a moderating role in this process. Cultivating psychological resilience in adolescents can effectively enhance their ability to cope with the impacts of sudden public events.

[Objective] The limit of exploitable energy resources on land and near-shallow offshore, the modern social demand for clean energy, and the more serious pollution and higher greenhouse gas emissions from fossil energy production and consumption activities relative to renewable and clean energy have made the development of deep-far offshore wind power a key area in the new round of energy revolution. Examining the relevant policies and laws in China from the perspective of scientific and technological innovation, discovering the problems and proposing solutions to them could provide guarantees of policies and laws for promoting high-quality development of China’s deep-far offshore wind power. [Methods] Taking the paradigm of the science of field law, and employing logic and normative analysis methods, this study examined the effect and efficiency of promoting and safeguarding scientific and technological innovations in the policies and laws for China’s development of deep-far offshore wind power. [Results] We found that the lack of drive of science and technology in the current policies and laws is manifested in three aspects. (1) The lack of policy guidance in terms of strategic position and planning system; (2) The lack of legal protection, which is manifested in the status of scientific and technological innovation in legislative orientation, and the connectivity of the laws on deep-far offshore wind power to the general legal system on scientific and technological innovation; (3) The lack of procedural synergy and substantive synergy between policies and laws. [Conclusion] In order to address or these deficiencies, the following approaches could be employed: (1) Enhancing the strategic status of deep-far offshore wind power, with basic policies guiding the direction of scientific and technological innovation and supportive policies as complement, while formulating relevant development plans in time; (2) Specifying the core status of scientific and technological innovation on deep-far offshore wind power in relevant laws and strengthening the connectivity of the laws on deep-far offshore wind power to the general legal system on scientific and technological innovation; and (3) Strengthening the synergy among policies and laws in terms of both procedure and substance.

ObjectiveTo investigate self-stigma’s influence on schizophrenia patients’ quality of life and its mediated impact by various factors.MethodsThis study adopted a cross-sectional design and randomly selected 170 hospitalized patients with schizophrenia for evaluation. The assessment tools included the Positive and Negative Syndrome Scale (PANSS), Internalized Stigma of Mental Illness Scale (ISMI), Schizophrenia Quality of Life Scale (SQLS), and Coping Questionnaire for Schizophrenia Patients (CQSP), among others. Correlation analysis, regression analysis, and mediation analysis were used to test the correlation and mediation effects.ResultsSelf-stigma had a significant impact on quality of life (T = 8.13, p = 0.00). When self-stigma is used as a mediator, the problem-solving factor in coping strategies has an indirect effect on quality of life, which is significant (AB = -0.16, P = 0.02), while the avoidance factor in coping strategies has a direct effect on quality of life, which is significant (C’ = 0.54, p < 0.001), and an indirect effect, which is also significant (AB = 0.25, p < 0.001).ConclusionThe study highlights the significant impact of self-stigma on the quality of life of schizophrenia patients, emphasizing the crucial roles of self-esteem and coping strategies. These findings suggest clinical interventions to improve quality of life should focus on reducing self-stigma, especially enhancing self-esteem and promoting adaptive coping strategies. By addressing these factors, we can better support the mental health and well-being of those with schizophrenia, offering an effective approach to rehabilitation.

Photobiomodulation therapy (PBMT) is the use of red or near-infrared light to heal, restore, and stimulate physiological processes that repair damage caused by trauma or a disease. PBMT is widely used in sports injuries, arthritis, neuropathic pain, and back and neck pain. In recent years, PBMT is a safe and effective tool for toxic reactions associated with cancer treatment, such as oral mucositis in patients undergoing chemo-radiotherapy for head and neck cancer or stem cell transplantation, radiation-associated dry mouth, taste disorders, radiation dermatitis, post-radiotherapy fibrosis, and lymphedema associated with head and neck cancer and breast cancer. However, the equipment and optimal dosimetric parameters for PBMT have not been fully defined and need to be further explored.

Objective The 9-item Patient Health Questionnaire (PHQ-9) was used to screen the depression status of inpatients with liver disease in the Infection Department of a grade A hospital, and nursing interventions were taken for patients with moderate and severe depression during hospitalization, so as to reduce the depression of patients with liver disease during hospitalization and promote their mental health and rehabilitation. Methods Using PHQ-9 for depression screening, 163 hospitalized patients with liver diseases in the Infection Department were evaluated from August 1, 2021 to December 31, 2021, and the data were analyzed. According to the results of PHQ-9 depression screening scale, patients with moderate and severe liver disease depression were given 15 days of nursing interventions. Results The results showed that there were 63 (38. 65%)patients with depression, of which 39(61. 90%) cases of mild depression, 15(23. 81%) cases of moderate depression, 7(11. 11%)cases of moderate to severe depression, and 2(3. 17%)cases of severe depression. Items with high total score included: Item ④: Feeling tired or lack of energy; Item③: Difficulty falling asleep, restless sleep or excessive sleep; Item①: Not feeling energetic or interested in doing things; Item⑤: Loss of appetite or eating too much. After implementation of nursing interventions, 3 patients with moderate-to-severe depressive liver disease were identified as been mildly depressed, 4 patients with moderate-to-severe depression and 2 patients with severe depression were identified as been moderately depressed. Conclusion The depression status of inpatients with liver disease is associated with to the treatment and rehabilitation of the patient during hospitalization, and also seriously affects the physical and mental health of patients, which needs to be paid attention to by all medical workers. The screening scale has positive significance for screening patients with depression due to liver disease, and nursing intervention measures for patients with moderate to severe and severe depression due to liver disease have achieved certain results. (目的 通过PHQ-9抑郁筛查量表对某三级甲等医院感染科肝病住院患者入院时的抑郁状况进行筛查, 并在住院期间对中重度及重度抑郁的肝病患者采取护理干预, 以缓解住院期间肝病患者的抑郁情绪, 促进患者心理健康及疾病康复。方法 2021年8月—12月, 采用PHQ-9抑郁筛查量表对某三级甲等医院感染科163例肝病住院患者进行入院评估, 并进行数据分析, 根据PHQ-9抑郁筛查量表结果对中重度及重度肝病抑郁患者采取为期15 d的护理干预。结果 筛查结果显示, 抑郁症状患者63(38. 65%)例, 其中轻度抑郁39(61. 90%)例, 中度抑郁15(23. 81%)例, 中重度抑郁7(11. 11%)例, 重度抑郁2(3. 17%)例。总得分较高的条目包括: 条目④感觉疲惫或没有活力; 条目③入睡困难、睡不安稳或者睡眠过多; 条目①做事时提不起劲或没有兴趣; 条目⑤食欲不振或吃太多。经15 d的护理干预后, 3例中重度抑郁患者变为轻度抑郁, 4例中重度抑郁患者及2例重度抑郁患者变为中度抑郁。结论 医院感染科肝病住院患者入院时的抑郁状况关系到患者住院期间的治疗与康复效果, 也严重影响患者的身心健康, 需引起全体医护工作者的重视。科室采用PHQ-9抑郁筛查量表对筛查肝病抑郁患者有积极意义, 针对中重度及重度肝病抑郁患者采取的护理干预措施达到了一定的效果。)

IntroductionSeveral small sample-sized clinical trials have demonstrated a beneficial effect of statin on depressive mood among major depressive disorder (MDD) patients. However, observational studies have showed the increased risk of anxiety/depression with statin treatment. Therefore, we aimed to evaluate the effects of statin on depressive mood and inflammation status among MDD patients.MethodsWe performed an updated meta-analysis RCTs identified in systematic searches of PubMed, Cochrane library, Embase, ClinicalTrials.gov, CNKI, Wan fang, VIP, and SinoMed database (up to August 2023). The primary endpoint was the Hamilton depression rating scale (HDRS). The secondary endpoints were rate of response to treatment, remission rate, levels of C-reactive protein (CRP), cognition and blood lipid. We evaluated the certainty of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.ResultsThe search identified seven RCTs involving 448 patients with a median follow-up of 10.4 weeks (range, 6–12 weeks). Compared with selective serotonin reuptake inhibitors (SSRIs) alone, treatment with statin plus SSRIs was associated with a significantly decreased HDRS [mean difference (MD) = −2.79; 95% confidence interval (CI): −3.83 to −1.76] and C-reactive protein (MD = −0.42 mg/L; 95% CI: −0.53 to −0.12 mg/L), and decreased levels of lipid profiles (P < 0.05). Moreover, statin plus SSRIs was associated with a comparable rate of treatment response [relative risk (RR) = 1.26; 95% CI: 0.98 to 1.62], remission rate (RR = 1.33; 95% CI: 0.89 to 1.99). Meta-regression indicated that the follow-up period was a source of heterogeneity regarding the HDRS (r = 0.302, P = 0.041). The quality of evidence was rated as moderate for HDRS and response rate according to the GRADE.ConclusionStatin could safely and effectively improve the symptoms of depression and inflammation status among MDD patients.Systematic review registrationhttps://inplasy.com/inplasy-2022-3-0016/, identifier INPLASY2022230016.

BackgroundChronic schizophrenia is significantly influenced by negative symptoms, with several known contributors to secondary negative symptoms. However, the impact of these factors and negative symptoms on social functioning warrants further exploration.MethodsWe assessed the clinical symptoms, antipsychotic adverse reactions, and social functioning of 283 hospitalized patients with chronic schizophrenia using various standardized interviews and scales. We conducted multiple regression and mediation analyses to elucidate the impact of secondary factors on negative symptoms, and the relationship among these “secondary factors,” negative symptoms, and social functioning.ResultsOur findings identified depressive symptoms, extrapyramidal symptoms, and positive symptoms as significant contributors to secondary negative symptoms. We found that negative symptoms play a notable mediating role in the effect of depressive and positive symptoms on social functioning. However, the relationship between positive symptoms, negative symptoms, and social functioning proved to be intricate.ConclusionOur findings propose that negative symptoms act as pivotal mediators in the correlation between “secondary factors” (including the depressive symptoms and positive symptoms) and social functioning. The treatment of chronic schizophrenia necessitates focusing on key factors such as depressive and positive symptoms, which might significantly contribute to the development of secondary negative symptoms. Further research is essential to clarify the complex relationship among positive symptoms, negative symptoms, and social functioning in schizophrenia.

This article presents a weighing preparation method for reference gases of nitric oxide (NO) in carbon dioxide (CO2). High-purity standard gases - NO and CO2 are used as raw materials. The relative expanded uncertainty of concentration analytic results of NO in CO2 reference gases is 3% (k=2), which proves excellent uniformity and stability of the prepared reference gases that can be used for accuracy evaluation of analytic instruments applied to detection of NO in food additive CO2. The preparation method can also be applied to prepare other reference gases with variety of concentrations and components.

The microstructure of Sn35Bi-xCo(x=0%, 0.3%, 0.7%, 1.0%, 1.2%, 1.5%, mass fraction) composite solder/Cu joints was observed by scanning electron microscopy (SEM).Combined energy spectrum (EDS) and XRD analysis, the difference of joint structure was studied. The mechanical properties of joints were tested by universal testing machine, and the influence mechanism of Co particle content on the structure and properties of SnBi/Cu joints was studied. The results show that, with the increase of Co particle content, the wettability of Sn35Bi-Co composite solder increases first and then decreases. When Co particle content is 0.7%, the wettability is the best.When appropriate amount of Co particles is added to the Sn35Bi/Cu joint in the solidification stage, the weld microstructure can be effectively refined, the IMC layer of the interface is more flat, Co atoms in the weld replace Cu atoms in the interface Cu6Sn5 layer, and the (Cu, Co)6Sn5 solid solution can be formed, which can strengthen the IMC layer of the interface.The shear strength of Sn35Bi-Co/Cu joints increases first and then decreases with the increase of Co particle content. When Co particle content is 0.7%, the maximum value of 54.09 MPa is obtained.

The laser welding-brazing technology assisted by alternating magnetic field was adapted to AZ31B and Q235. In order to improve the mechanical properties of the joint, Ni interlayer was added to coordinate the metallurgical connection between magnesium alloy and steel, longitudinal alternating magnetic field was applied to optimize the weld forming. The results show that the IMC layer of the joint in fusion welding zone assisted by alternating magnetic field with Ni interlayer is composed of dendrite or continuous nanoscale layered AlNi phase. Magnesium alloy and steel realizes metallurgical connection by laser welding-brazing. The thickness of Fe-Ni solid solution decreases and extends into the weld of magnesium side after the application of alternating magnetic field, and increases the interface bonding area increases by the gully like Fe-Ni solid solution. The actual interface connection length is the main factor affecting the tension shear line load of the joint. The actual interface connection length and the tension shear line load of the welding-brazing joint exhibit first increasing and then decreasing trend as the increase of the magnetic field intensity (B). When the laser power P=1250 W, welding speed v=20 mm·s-1, B=10 mT, frequency f=35 Hz, magnesium alloy and steel are able to achieve the metallurgical connection by the addition of Ni interlayer and the weld forming of the joint is optimized by applying longitudinal alternating magnetic field, the tension shear line load of the joint is the highest, reaching 163 N/mm.

Epoxy/polyamic acid (EP/PAA) adhesives with high polyimide precursor-PAA content have been synthesized and then cured. The structure, thermal, and adhesive properties were investigated by Fourier transform infrared spectroscopy, thermogravimetric analysis, and tensile shear test. The effects of PAA content and curing process on the tensile shear strength were also studied. The results showed that the addition of PAA improved the heat resistance and reduced the water absorption. EP/PAA adhesive kept good adhesion. A kind of EP/PAA composite adhesive with excellent comprehensive properties was prepared in this study.

The Sanhe Pb-Zn deposit is studied in this paper through detailed field and underground geological investigations, structural geological surveys, drilling profile analysis combined with petrological and mineralogical analysis of ores and altered wall-rocks. We then discussed the ore-controlling structures and their distribution patterns, the styles of mineralization and alteration, the coupling relation between the mineralization and fault structures. Our results show that the mineralization in the Sanhe deposit show structure-controlled characteristics, and with dominant ore bodies trending NWW, dipping SSW. The extent of the ore-controlling faults can reach hundreds of meters to a few kilometers long, with relative stable occurrence. In the field, the ore-controlling faults occur as altered foliated zones but with tensional breccia veins and druse texture in them, showing a reactivated shear fault signature. NWW- and NNE- trending faults show post-ore deformation characteristics and usually with lamprophyre, syenite porphyry or calcite ±quartz ±fluorite ±clay mineral veins occuring in them. The NNW- and NNE- trending faults and related veins crosscut the mineralized carbonate-quartz veins and NWW-trending faults indicating a post-ore brittle deformation and hydrothermal activity. The post-ore faults and related hydrothermal veins usually occur as branching, bifurcation or irregular shapes and with druse texture in the center of the veins implying a extensional faults. Although the post-ore faults can slightly dislocate the ore bodies and contemporaneous hydrothermal veins, the displacement is negligible for exploration. The alteration around the non-mineralized calcite veins is dominated by clay alteration together with minor disseminated pyrite. Combined the structure-controlled mineralization and the alteration related Pb-Zn minerlization, it is concluded that the NWW-tending faults with silicification, pyritization, chloritization alteration halo, can be used as significant prospecting criteria in the deposit and the neighbouring area.

During the drilling of shale gas wells, the shape of shale cuttings cut by polycrystalline diamond compact bits has an obvious flaky structure. The accumulation of such flaky cuttings is one of the main reasons for high drilling torque and drag and serious back pressure, which affect the drilling speed of the horizontal section of shale gas wells. Therefore, predicting the thickness of the flaky cuttings bed and restraining it are essential for ensuring safe and efficient drilling of the horizontal section of shale gas wells. However, most of the previous research on migration laws for cuttings were based on spherical particles, which affected the accuracy of cuttings bed thickness prediction. In this study, through visualization experiments combined with computational fluid dynamics numerical simulation, the hole cleaning laws of shale gas wells in the long horizontal section were studied, and a set of cuttings bed thickness prediction models and cuttings bed removal process parameter optimization methods were established. Field application was conducted in the Changning 209H24-1 well in the southern Sichuan Basin, China. The results revealed the following: (1) There are significant differences in the migration laws of flaky cuttings and spherical cuttings in the horizontal section. (2) The fitting accuracy of the established long horizontal fragmentation layer distribution model considering multiple factors and the experimental data is as high as 0.973. (3) Based on this model, the drilling parameters of the Changning 209H24-1 well were optimized, which played a good role in wellbore cleaning and ensured the safe and smooth implementation of the later casing operation.

Stress is a trigger for the development of psychiatric disorders. However, how stress trait differs in schizophrenia patients is still unclear. Stress also induces and exacerbates immune activation in psychiatric disorders. Plexins (Plxn) and its ligands semaphorins (Sema) are important cellular receptors with plural functions in both the brain and the immune system. Recently, the role of Plxn/Sema in regulation of neuroinflammation was also noticed. Here, when investigating immune mechanisms underlying stress susceptibility in schizophrenia, we discovered the role of Plxnb2 in stress response. Patients of first-episode schizophrenia (FES) with high stress (FES-hs, n=51) and low stress (FES-ls, n=50) perception and healthy controls (HCs) (n=49) were first recruited for neuroimaging and blood bulk RNA sequencing (RNA-seq). A mouse model of chronic unpredictable stress (CUS) and intra-amygdaloid functional blocking of Plxnb2 were further explored to depict target gene functions. Compared to HCs, FES-hs patients had bigger caudate and thalamus (FDR=0.02&0.001, respectively) whereas FES-ls patients had smaller amygdala (FDR=0.002). Blood RNA-seq showed differentially expressed PLXNB2 and its ligands among patient groups and HCs (FDR

Solvent molecules, especially coordinated solvent molecules, vastly affect the energetic properties of energetic coordination polymers (ECPs). Therefore, an effective strategy to maintain energetic properties is to reduce solvent molecules. In this paper, a nitrogen-rich energetic coordination polymer [Cu(HBTT)(H2O)]n (ECP 1) was synthesized and prepared by integrating the coordination mode. Its properties were adequately investigated, including crystal structure, thermal stability, energetic properties, and sensitivity. In terms of application, it was researched as catalysts for the thermal decomposition of AP and as a primary explosive for laser initiation. As revealed by single-crystal X-ray diffraction results, it crystallizes in and belongs to monoclinic space group P21/n with a 2D layer-like structure. Meanwhile, it has outstanding thermal stability (Tp = 357.2 °C, Ek = 201.78 kJ mol-1) according to differential scanning calorimetry (DSC) curves and thermogravimetric curves (TG). The detonation velocity and detonation pressure of ECP 1 (8.63 km s-1, 36.73 GPa) can bear comparison with RDX and HMX. The catalytic pyrolysis experiment indicates that AP/ECP 1 (10 wt%) can accelerate the thermal decomposition of AP, with the high temperature for decomposition decreasing to nearly 80 °C. The activation energy (Ek) of AP decreased from 217.36 kJ mol-1 to 185.96 kJ mol-1 by adding ECP 1. Meanwhile, ECP 1 has a preliminary response to laser initiation. These results are conducive to the quick development of ECPs.

In this study, a novel functional monomer N-(1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl)ethyl)acrylamide (NDTEA) was designed and synthesized, and was used to prepare Ni(ii) ion-imprinted polymers (Ni(ii)-IIPs). Sixteen kinds of Ni(ii)-IIP (Ni(ii)-IIP1–16) and corresponding non-imprinted polymers (NIP1–16) were prepared by precipitation polymerization method. After optimized condition experiment, Ni(ii)-IIP5 possessed maximum adsorption capacity and better imprinting factor under optimal experimental conditions which indicated by equilibrium adsorption experiments. The morphology and structural characteristics of Ni(ii)-IIP5 were characterized by scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET). The adsorption selectivity of Ni(ii)-IIP5 was analyzed by ICP-OES, and the results showed that Ni(ii)-IIP5 had favorable selectivity recognition ability for Ni(ii) when Cu(ii), Co(ii), and Cd(ii) are used as competitive ions. The kinetic experiment indicated that the performance of Ni(ii) adsorption on the surface of Ni(ii)-IIP5 obeyed the pseudo-first-order model, and adsorption equilibrium was attained after 15 min. Isothermal adsorption process fitted to Langmuir and Freundlich isothermal adsorption models, simultaneously. The results showed that Ni(ii)-IIP5 prepared by using a new functional monomer had better permeation selectivity and higher affinity for Ni(ii), which also verified the rationality of the functional monomer design. At the same time, it also provided a broad application prospect for removal of Ni(ii) in complex samples.

The current study aims to use the molecular dynamics (MD) simulation method to discuss the glass transition behaviour and fractional free volume (FFV) of the pure polyethylene terephthalate (PET) and the plasticized PET induced by supercritical carbon dioxide (SC-CO2) sorption. The adsorption concentration reproduced through sorption relaxation cycles (SRC) was firstly estimated and in an order of magnitude with the known experimental results available in the reported literature. The FFV induced by SC-CO2 in PET polymer changes regularly, which is proportional to the capacity of SC-CO2 adsorption with the changes in temperature and pressure. The glass transition temperature (Tg) was further estimated to be almost identical to the known experimental values and shows a gradually decreasing tendency with the increase of pressure. Meanwhile, the plasticization of PET polymer studied by radial distribution functions showed that CO2 molecules occupying the sorption sites on the PET backbone promoted plasticization by increasing the fluidity of the PET backbone chain.

Objective To explore the mechanism of HIF-1α promoting malignant development of nasopharyngeal carcinoma by upregulating PD-L1 expression under hypoxic conditions. Methods CNE2 cells were divided into normoxia (20%O2), hypoxia (1%O2), HIF-1α-siRNA+hypoxia and NC-siRNA+hypoxia groups. Cell proliferation, apoptosis, the mRNA levels of HIF-1α, STAT3 and PD-L1, the protein levels of HIF-1α, PD-L1, STAT3 and STAT3 phosphorylation were detected by MTT assay, flow cytometry, RT-PCR and Western blot, respectively. Results Cell proliferation of hypoxia group was significantly higher than that of normoxia group (P=0.000). The cell proliferation rate of HIF-1α-siRNA+hypoxia group was significantly lower than those in other groups (P=0.000). The apoptosis rate of HIF-1α-siRNA+hypoxia group was remarkably higher than those in other groups (P=0.001). RT-PCR detection showed that the mRNA levels of HIF-1α, PD-L1 and STAT3 in the HIF-1α-siRNA+hypoxia group were significantly lower than those in hypoxia group and NC-siRNA+hypoxia group. The protein expression of HIF-1α, PD-L1 and STAT3 showed similar tendency in Western blot assays compared with the mRNA levels. The pSTAT3 protein expression level in HIF-1α-siRNA+hypoxia group was significantly lower than those in hypoxia group and HIF-1α-siRNA+hypoxia group (P=0.001). Conclusion Under hypoxic microenvironment, HIF-1α may up-regulate the expression of PD-L1 through STAT3, thereby promoting the immune escape of cancer cells, leading to the malignant development of nasopharyngeal carcinoma.

Radiotherapy combined with chemotherapy is the main treatment for stage Ⅱ-Ⅳa nasopharyngeal carcinoma (NPC). In the era of intensity-modulated radiation therapy, the timing and implementation of chemotherapy are still controversial. In the past, the clinical guidelines for NPC generally described the specific radiotherapy technology, dose fractionation and the specific scheme of combined application of radiotherapy and chemotherapy, and may lack specific practical guidance. The joint international guidelines for NPC by CSCO and ASCO elaborates the mode and specific implementation recommendations of radical chemoradiotherapy for stage Ⅱ-Ⅳa NPC. This article aims to interpret the specific details of the guideline.

Abstract The single‐phase‐to‐ground faulty line selection methods based on the signals of the frequency above 10 Hz has a low discrimination of fault characteristic signal and characteristic signal may be covered by noise in cases of high‐resistance fault. To solve the problem, a line selection method based on system's own extremely low frequency signal (SOELFS) is proposed. Due to the obvious attenuation characteristic of extremely low frequency signals in healthy lines, the extremely low frequency signal has a larger discrimination and hardly affected by imbalanced current noise. Moreover, as the amplitude of the SOELFS is affected by the initial phase angle of the fault, an additional line selection method based on artificially injected extremely low frequency signal is proposed. Cooperating with the specially designed and implemented measuring device, simulations and experimental verification are carried out. The results show that the discrimination of characteristic signal increases from 31 obtained by power frequency to more than 500, the high‐resistance fault protection ability increases from 2 to 10 kΩ.

A reliable aging-prediction method is significant for lithium-ion batteries (LIBs) to prolong the service life and increase the efficiency of operation. In this paper, an improved Gaussian-process regression (GPR) is proposed to predict the degradation rate of LIBs under coupled aging stress to simulate working conditions. The complicated degradation processes at different ranges of the state of charge (SOC) under different discharge rates were analyzed. A composed kernel function was conducted to optimize the hyperparameter. The inputs for the kernel function of GPR were improved by coupling the constant and variant characteristics. Moreover, previous aging information was employed as a characteristic to improve the reliability of the prediction. Experiments were conducted on a lithium–cobalt battery at three different SOC ranges under three discharge rates to verify the performance of the proposed method. Some tips to slow the aging process based on the coupled stress were discovered. Results show that the proposed method accurately estimated the degradation rate with a maximum estimation root-mean-square error of 0.14% and regression coefficient of 0.9851. Because of the proposed method’s superiority to the exponential equation and GPR by fitting all cells under a different operating mode, it is better for reflecting the true degradation in actual EV.

Affected by multiple stages of tectonic movements, the Wushi Sag in the Beibuwan Basin has formed complex internal structures. Accurately identifying the structural development characteristics of different stages has a great significance for oil and gas exploration. In this paper, we used the high-precision 3D seismic and drilling data to analyze the fault type, combination pattern, evolution rule and dynamic mechanism in the east area of the Wushi sag. The results show that under the influence of the regional stress of extension-strike-slip and weak compression caused by the interaction between the Pacific plate, the Indian plate and the Eurasian plate, three sets of extension-strike-slip-compression fault systems were developed in the east area of the Wushi sag, and 13 types of plane and profile fault combinations are identified. The formation and evolution of the fault system endured five main stages, including the initial weak rifting stage in the Paleocene, the main extension stage in the Eocene, the strike-slip and weak extension stage in the Early and Middle Oligocene, the strike-slip and weak compression stage in the late Oligocene, and the final stage since the Neogene.

Three-dimensional stability analysis of soil slopes remains a hot topic in the field of geotechnical engineering. Considering the fluid–solid coupling effect, this study performs a number of numerical analyses on the stability of a 3D excavation slope located in the Wuxi Taihu Tunnel, China. Three typical cases of the issued slope are investigated, i.e., the slope at the initial state, with the water-stop curtain, and with both the water-stop curtain and concrete-sprayed layer. The shear strength reduction method was adopted to determine the factor of safety (FOS) of the slope. The distributions of pore pressures and wetting lines, the horizontal and vertical displacements, and the critical slip surface are presented. The results indicate that the water-stop curtain can prevent the groundwater seepage effectively. The water-stop curtain and concrete-sprayed layer are effective in restraining the slope deformation, altering the critical slip surface, and improving the slope safety.

Objective To investigate the effect of whole-course nutrition support on nutritional status of patients with locally advanced nasopharyngeal carcinoma (NPC). Methods We randomly divided 96 locally advanced NPC patients into the experimental group (whole-course nutrition support combined concurrent chemoradiotherapy, n=45) and the control group (only concurrent chemoradiotherapy, n=45). PG-SGA questionnaire, the anthropometry measurements, hematological indexes and acute radiology reactions were used to observe the nutritional status of NPC patients and analyzed the effect of whole-course nutrition support on nutritional status. Results PA and Hb of control group were significantly declined and Hb was significantly lower than that of the experimental group at the 2nd week of radiotherapy. At the 4th week of radiotherapy, the weight of control group were significantly lower than that before radiotherapy, and the weight, BMI, TP, ALB and PA of the experimental group were higher than those in control group. PG-SGA score and the incidence of severe malnutrition of control group were significantly higher than those of the experimental group at the end of radiotherapy. The grading of myelosuppression, oral mucositis and dysphagia of control group were significantly higher than those of the experimental group during radiotherapy. Conclusion Whole-course nutrition support can significantly retard the weight loss and the sustained decline in hematological indexes, reduce the acute radiation reactions, and then effectively improve the nutritional status and reduce the incidence of severe malnutrition of locally advanced NPC patients.

Objective To analyze nutritional status and influencing factors of patients with nasopharyngeal carcinoma (NPC) during chemoradiotherapy. Methods We reviewed retrospectively the clinical data of 140 NPC patients. PG-SGA questionnaire, the anthropometry measurements, hematological indexes, side-effects of chemoradiotherapy and quality of life were used to evaluate nutritional status of NPC patients. Multivariate Logistic regression model was used to analyze the main influence factors for malnutrition of NPC patients. Results During chemoradiotherapy, 80.7% of the NPC patients had severe malnutrition, 95.0% lost weight, 39.3% lost weight more than 10%. Prealbumin declined significantly at the 2nd week of radiotherapy, and the rate of anemia was 54.3% at the end of radiotherapy. The score of overall QOL was only 38.9 at the end of radiotherapy. Clinical stages, weight loss during chemoradiotherapy, prealbumin, anemia, oral mucositis, overall QOL and economic status were influence factors for malnutrition of NPC patients (all P < 0.05). Conclusion The incidence of malnutrition is high in NPC patients during chemoradiotherapy. Clinical stages, weight loss during chemoradiotherapy, anemia, oral mucositis and financial difficulty are the independent risk factors for the malnutrition of NPC patients. Prealbumin and overall QOL are the independent protective factors for the malnutrition of NPC patients.

The advent of planar metalenses, including the super-oscillatory lens (SOL) and the supercritical lens (SCL) with distinctive interference properties, has profoundly impacted on the long-lasting perception of the far-field optical diffraction limit. In spite of its conspicuous success in achieving marvelously small focal spots, the planar metalens still faces tough design and fabrication challenges to realize high focusing efficiency. In this work, we demonstrated a dual-mode laser fabrication technique based on two-photon polymerization for realizing the multilevel phase SCL with focusing efficiency spiking. Synergistically controlling two types of movement trajectory, which is implemented with the piezo stage and the scanning galvo mirror, enables the fabrication of complicated structures with sub-diffraction-limit feature size. By utilizing such advantage, SCLs with discretized multilevel phase configurations are explicitly patterned. The experimental characterization results have shown that a four-level phase SCL can focus light into a sub-diffraction-limit spot with the lateral size of 0.41 λ/NA (NA is the numerical aperture), while achieve the focal spot intensity and the energy concentration ratio in the focal region 7.2 times and 3 times that of the traditional binary amplitude-type SCL with the same optimization conditions, respectively. Our results may release the application obstacles for the sub-diffraction-limit planar metalens and enable major advances in the fields from label-free optical super-resolution imaging to high precision laser fabrication.

In this study, we have theoretically designed a micro-structured photoconductive antenna based on the combination of split-ring resonator (SRR) and dipole photoconductive antenna. Further, we have used numerical simulations to prove that the proposed antenna can enhance the terahertz radiation characteristics. According to the equivalent circuit model analysis, the terahertz radiation power and the resonance frequency of this antenna were found to be closely related with the structural parameters of the SRR. A numerical model was established to simulate the effect of the structural parameters of SRR on the terahertz radiation characteristics of the proposed antenna. The results indicated that an increase in the width and length of SRR caused an increase in the peak power intensity and a decrease in the resonance frequency. Moreover, as the gap width of SRR was increased, the peak power intensity was decreased and the resonance frequency was increased. Furthermore, the terahertz radiation power increased with increase in the gap width of antennas. Overall, we show that high-power terahertz radiation sources with specific frequency can be obtained by optimizing the structural parameters of SRR, and such sources are potentially useful in a variety of fields such as biomedicine, material analysis, and detection systems.

To study the effects of focusing distance on the characteristics of copper plasma, a picosecond laser is utilized to ablate a pure copper plate to generate a plasma spectrum. Following numerous experiments on the subject, three significant factors are determined: lens focal length, pulse energy, and the lens-to-sample distance. These factors are employed to analyze the spectral intensity, plasma temperature, and electron density in the local thermodynamic equilibrium (LTE) and optically thin condition. Due to the shielding effects of mixed plasma, the strongest spectral intensity is achieved in the prefocused case, no matter how much beam irradiance is employed. The more intensive the beam irradiance is, the more the optimal position is distant from the focal point. The variation of plasma temperature and electron density showed a peak in the prefocused case, which is consistent with the trend of spectral intensity. For the case of extremely high irradiance (on the focus), the shielding effects become seriously, and the resultant above three factors decreased sharply. When a longer-focal-length lens is employed, the spectral intensity exhibited an obvious bimodal trend. In the prefocused case, a longer-focal-length lens is helpful to eliminate the effects of the roughness of the target surface compared with a shorter one. Finally, the assumed LTE is validated by McWhirter relation, plasma relaxation time, and diffusion length, and the optically thin condition was also validated by spectral intensity ratio. We hope that this work could be an important reference for the future design of highly optimized experiments for Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS).

As a sample pretreatment device, microwave digestion instrument is widely used in biochemical laboratories. The temperature parameters of the microwave digestion instrument directly decide the accuracy of the experimental results. At present, there is no relevant calibration specification，method or device for microwave digestion system in China. Due to the special working principle of the microwave digestion instrument, the calibration device must be used in the high temperature microwave environment, and the ordinary temperature measuring device will cause ignition, explosion and other phenomena, which will endanger the life and health of the calibration personnel. This article presents a set of calibration device for microwave digestion system, with measuring range of (0~200) °C, accuracy of no less than ± 0.1 °C, and resolution of 0.01 °C. The presented device also solves the potential problems of ignition and explosion, which commonly exist in ordinary temperature measuring devices.

Background: Obsessive-compulsive disorder (OCD) and tic disorders (TDs) are closely related and considered to etiologically overlap. Both disorders are characterized by repetitive behaviors. TD and OCD often co-occur. The high comorbidity between OCD and TD individuals suggests that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD. To date, there has been no systematic nationwide epidemiological survey of the mental health (including tic disorders and obsessive-compulsive disorder) of children and adolescents in China. Methods: A two-stage epidemiological study of psychiatric point prevalence was conducted. We used the multistage cluster stratified random sampling strategy to assess five provinces of China. The Child Behavior Checklist was used to identify behavioral problems among the enrolled students in the first stage. The results from the Mini-International Neuropsychiatric Interview for Children and Adolescents and evaluations from two psychiatrists based on the Diagnostic and Statistical Manual-IV were used to make a diagnosis. Point weighted prevalence for TD and OCD was estimated. We adjusted prevalence estimates with the product of sampling weights and poststratification weights. Standard error values and 95% confidential intervals were generated with Taylor series linearization. Rao–Scott adjusted chi-square (χ2) tests were employed to compare the prevalence estimates of different age and sex groups. Results: In the first stage, 73,992 participants aged 6–16 years old were selected. The prevalence rates of OCD and TDs were 1.37% (95% CI: 1.28–1.45) and 2.46% (95% CI: 2.35–2.57), respectively. The prevalence of OCD was found to be higher in girls (p < 0.001) and higher in boys with transient tic disorder (TTD) (p < 0.001) and Tourette’s syndrome (TS) (p < 0.001). The most common comorbidity of TS was OCD (40.73%), and for OCD, it was TS (11.36%). Conclusions: Our study is the first nationwide survey on the prevalence of TD (2.46%) and OCD (1.37%) in school students aged 6–16 years old in China. The high comorbidity between OCD and TD individuals suggested overlap based on the prevalence dimensions, which might be influenced by age and sex. This result suggested that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD.

Given the extensive use of antibiotics at present, the identification of antibiotics and production quality monitoring are of high importance. However, conventional antibiotic identification methods have a low sensitivity and a long detection time. Here, we propose an identification method that combines terahertz (THz) spectroscopy and chemometric technology. THz time-domain spectroscopy (THz-TDS) was performed for sixteen types of antibiotics, including β-lactam, cephalosporins, macrolides, and tetracyclines. The absorption spectra within the frequency range of 0.2–1.5 THz were calculated. For dimensionality reduction, principal component analysis (PCA) and t-distributed stochastic neighbor embedding (t-SNE) were implemented, respectively. The data after dimensionality reduction were input into a support vector machine (SVM). The model parameters were optimized through grid search (GS), genetic algorithm (GA), and particle swarm optimization (PSO) methods, and the optimal identification results were obtained after comparison across these methods. Experiments indicate a differentiation of the THz absorption spectra among the sixteen types of antibiotics. After dimensionality reduction, the training time of the model significantly decreased. The use of the t-SNE-PSO-SVM model achieved the highest average accuracy on the prediction set, which was 99.91%. Thus, our study does not only confirm that the t-SNE-PSO-SVM model proves to be a reliable method for antibiotics identification, but also confirms that the combination of THz-TDS and chemometric pattern recognition has great potential for drug detection.

Critical minerals refer to minerals that have an important strategic position in high-tech application and economic development such as national defense, military industry and emerging industry, but their resource security is at risk. In the context of a new round of technological revolution and industrial transformation, critical minerals have become the focus in the world competition. The United States, the European Union, Japan, Canada, Australia and China have released the lists of critical minerals respectively. Their lists have a high degree of coincidence. In terms of the demand and governance situation, the distribution areas of critical minerals are highly concentrated but their demand shows structural differentiation. Moreover, developed countries have great power but China has weak power in the global governance of critical minerals. In terms of improving the global governance capability, China needs to create the evaluation system for sustainable development of critical minerals, strengthen international cooperation, promote the reform of governance and enhance China’s voice in the word. Moreover, China should carry out the strategy of critical minerals reserves.

In this paper,the research of the scraper conveyor is carried out,the force analysis of the adjacent middle pan group and the dumbbell pin is carried out,and the dumbbell pin load data is obtained by the dumbbell pin load test system. The ANSYS/ls-dyna software is used to simulate the nonlinear contact dynamics of the middle pan group and the dumbbell pin under the push-slip condition of the scraper conveyor. The contact stress of the dumbbell pin is the largest,and the maximum contact stress of the dumbbell pin occurs at the abrupt change of the dumbbell pin section,and the maximum contact stress of the dumbbell pin And the contact stress concentration between the two middle slots occurred at the joints of the dumbbell pin and the middle ditch. The simulation results were in accordance with the actual working conditions. This study provides a dumbbell pin load test program,and through the test simulation to verify its correctness and feasibility,while the middle slot and dumbbell pin structure size optimization method.

In traditional laser-induced breakdown spectroscopy (LIBS) applications, the line intensity and analysis capability are susceptible to plasma shielding. To investigate the shielding effects on the characteristics of Cu plasma in air, a ~120-picosecond laser with a wavelength of 1064 nm was employed to produce plasma. The plasma temperature and electron density were calculated under the condition of local thermal equilibrium (LTE) and optically thin, while the relationships between the line intensity, plasma temperature and electron density were analyzed. Moreover, the LTE condition was validated by the McWhirter relation, plasma relaxation time and diffusion length, and the optically thin condition was observed through the variation in line intensity. The results indicated that when the focal point was below the target surface, the plasma shielding was the weakest, and the highest line intensity could be obtained. In addition, there was a positive correlation between the increased plasma temperature and the degree of shielding effect. When the focal point was above the target surface, the high-irradiance pulse directly broke down the free air and produced a shock wave. Under the high pressure of the over-heated shock wave, the line intensity, plasma temperature and electron density increased again. This study provides an important insight into the experiments and applications of picosecond LIBS.

In order to increase the terahertz output power of the photoconductive antenna, a new multiple terahertz power synthesis technology based on terahertz time domain spectroscopy waveform consistency is proposed. The dipole photoconductive antenna with 500-μm aperture and a plurality of delay lines are used to build multiple terahertz power synthesis system. A synthesis efficiency evaluation method is proposed on the basis of the temporal coherence degree. The terahertz time-domain spectroscopy signals can be generated synchronously by virtue of the precise control of multiple delay lines, which can be realized the maximizing frequency domain peak power. Experimental results showed that the synthesized time-domain spectroscopy signal peaks and frequency domain power peaks are maximized, when the terahertz optical path difference is consistent. Two channel, three channel, and four channel synthetic temporal coherence values are 99.47%, 90.45%, and 83.37%, respectively, and the terahertz radiation power peaks can reach 1.94, 2.27, and 2.45 times the peaks before synthesis, respectively.