Preparation and Properties of Natural Bamboo Fiber-Reinforced Recycled Aggregate Concrete.

To promote resource reuse and the green, low-carbon transformation of the construction industry, this study uses recycled aggregate from crushed waste concrete and natural bamboo fibers to formulate bamboo fiber-reinforced recycled-aggregate concrete. This study investigates the effects of natural bamboo fiber (NBF) content, NBF length, and the water-to-cement ratio on the performance of concrete through an orthogonal experiment to determine the optimal mixing proportions of NBF-reinforced concrete. Additionally, recycled aggregate completely replaced natural aggregate. The mechanism by which NBF influences concrete was also analyzed. The results demonstrate that the NBF-reinforced specimens exhibited good integrity during compression failure, with NBFs effectively tying the concrete together. The optimized parameters for NBF-reinforced concrete were an NBF length of 20 mm, an NBF content of 0.4v%, and a water-to-cement ratio of 0.55. Almost no flaky Ca(OH)2 crystals were observed in the NBF-hardened cement-paste transition zone, indicating effective bonding at the interface.

[Comparative analysis of plastomes of Rubus chingii and R. chingii var. suavissimus].

Rubus chingii and R. chingii var. suavissimus are unique dual-purpose plant resources, with significant nutraceutical, pharmaceutical, and economic value, as well as promising prospects for further development. To investigate the genetic structure and evolutionary characteristics of these two varieties, this study conducted plastome sequencing using the Illumina HiSeq XTen sequencing platform. Subsequently, the study performed assembly, annotation, and characterization of the genomes, followed by a comparative plastome and phylogenetic analysis using bioinformatics techniques. The results revealed that the plastomes of R. chingii and R. chingii var. suavissimus exhibited a tetrad structure, comprising a large single-copy region(LSC), a small single-copy region(SSC), and two inverted repeat regions(IRs). The study identified a total of 56 simple sequence repeats(SSRs) after comparative analysis, predominantly consisting of A and T. Furthermore, the structure of the IR boundary genes in both varieties was found to be highly conserved, with only minor nucleotide variations. Additionally, the study identified three highly variable regions: rps16-trnQ-psbK, trnR-atpA, and trnT-trnL, which held promise as potential identification marks for further development and utilization. Phylogenetic analysis results obtained by the maximum likelihood and Bayesian inference methods demonstrated a close clustering of R. chingii and R. chingii var. suavissimus(100% support), with their closest relatives being R. trianthus. This study, focusing on plastome-level genetic distinctions between these two varieties, lays a foundation for future species protection, development, and utilization.

High levels of cadmium altered soil archaeal activity, assembly, and co-occurrence network in volcanic areas.

Soil microbial communities are essential to biogeochemical cycles. However, the responses of microorganisms in volcanic soil with high heavy metal levels remain poorly understood. Here, two areas with high levels of cadmium (Cd) from the same volcano were investigated to determine their archaeal composition and assembly. In this study, the Cd concentrations (0.32-0.38 mg/ kg) in the volcanic soils exceeded the standard risk screening values (GB15618-2018) and correlated with archaeal communities strongly (P < 0.05). Moreover, the area with elevated levels of Cd (periphery) exhibited a greater diversity of archaeal species, albeit with reduced archaeal activity, compared to the area with lower levels of Cd (center). Besides, stochastic processes mainly governed the archaeal communities. Furthermore, the co-occurrence network was simplest in the periphery. The proportion of positive links between taxa increased positively with Cd concentration. Moreover, four keystone taxa (all from the family Nitrososphaeraceae) were identified from the archaeal networks. In its entirety, this study has expanded our comprehension of the variations of soil archaeal communities in volcanic areas with elevated cadmium levels and serves as a point of reference for the agricultural development of volcanic soils in China.

Synthesis, structural characterization, analytical profiling, and application to authentic samples of synthesized Phase I metabolites of the synthetic cannabinoid 5F-MDMB-PICA.

5F-MDMB-PICA, an indole-type synthetic cannabinoid (SC), was classified illicit globally in 2020. Although the extensive metabolism of 5F-MDMB-PICA in the human body warrants the development of robust analytical methods for metabolite detection and quantification, a current lack of reference standards for characteristic metabolites hinders such method creation. This work described the synthesis of 18 reference standards for 5F-MDMB-PICA and its possible Phase I metabolites, including three hydroxylated positional isomers R14 to R16. All the compounds were systematic characterized via nuclear magnetic resonance, Fourier transform infrared spectroscopy, and high-resolution mass spectrometry. Furthermore, two methods were developed for the simultaneous detection of all standards using liquid chromatography-tandem mass spectrometry and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. By comparison with authentic samples, R17 was identified as a suitable urine biomarker for 5F-MDMB-PICA uptake.

[Latent classes of health risk behaviors and their relationship with self-control among rural secondary school students in Guizhou Province].

OBJECTIVE: To understand the potential categories of health risk Guizhou Province. METHODS: From November to December 2021, 4452 rural students in middle school students with average age of(13.5±1.6) years were selected from Guizhou Province by multi-stage stratified random cluster sampling method.1505(33.8%) students in the first grade, 1958(44.0%) students in the second grade and 989(22.2%) students in the third grade. There were 2295 boys(51.5%) and 2157 girls(48.5%). Basic information questionnaire, health risk behavior questionnaire and self-control scale were used for questionnaire survey. Latent category analysis was used to explore the potential categories of health risk behaviors, and disordered multiple classification logistic regression analysis was used to explore the relationship between potential categories and self-control. RESULTS: The health risk behaviors of rural middle school students in Guizhou Province could be divided into four potential categories: low risk group(71.4%), medium risk group(11.6%), sub-high risk group(5.2%) and high risk group(10.7%). There were statistically significant differences in the distribution characteristics of potential categories of junior middle school students with different gender, grade, nationality, only child, accommodation, stay-behind, academic performance, academic pressure, peer relationship, parent-child relationship, teacher-student relationship and domestic violence(P<0.05 or P<0.01). Taking the low-risk group as the reference group, the highest self-control scores were in the medium risk group(OR=1.049, 95%CI 1.040-1.058), the sub-high risk group(OR=1.098, 95%CI 1.083-1.113), and the high risk group(OR=1.077, 95%CI 1.066-1.087). CONCLUSION: The latent characteristics of health risk behavior of rural junior middle school students in Guizhou Province are obvious. Improving self-control ability can reduce the occurrence of medium risk group, sub-high risk group and high risk group.

[DUS testing guidelines for new varieties of Chinese medicinal plants].

A rich diversity of wild medicinal plant resources is distributed in China, but the breeding of new plant varieties of Chinese medicinal plants started late and the breeding level is relatively weak. Chinese medicinal plant resources are the foundation for new varieties breeding, and the plant variety rights(PVP) are of great significance for the protection and development of germplasm resources. However, most Chinese medicinal plants do not have a distinctness, uniformity, and stability(DUS) testing guideline. The Ministry of Agriculture and Rural Affairs has put 191 plant species(genera) on protection lists, of which only 30 are medicinal species(genera). At the same time, only 29 of 293 species(genera) plants in the Protection List of New Plant Varieties of the People's Republic of China(Forest and Grass) belong to Chinese medicinal plants. The number of PVP applications and authorization of Chinese medicinal plants is rare, and the composition of variety is unreasonable. Up to now, 29 species(genera) of DUS test guidelines for Chinese medicinal plants have been developed. Some basic problems in the breeding of new varieties of Chinese medicinal plants have appeared, such as the small number of new varieties and insufficient utilization of Chinese medicinal plant resources. This paper reviewed the current situation of breeding of new varieties of Chinese medicinal plants and the research progress of DUS test guidelines in China and discussed the application of biotechnology in the field of Chinese medicinal plant breeding and the existing problems in DUS testing. This paper guides the further application of DUS to protect and utilize the germplasm resources of Chinese medicinal plants.

Fabrication of a Molecularly-Imprinted-Polymer-Based Graphene Oxide Nanocomposite for Electrochemical Sensing of New Psychoactive Substances.

As new psychoactive substances (commonly known as "the third generation drugs") have characteristics such as short-term emergence, rapid updating, and great social harmfulness, there is a large gap in the development of their detection methods. Herein, graphite oxide (GO) was first prepared and immobilized with a reversible addition-fragmentation chain transfer (RAFT) agent, then a new psychoactive substance (4-MEC) was chosen as a template, and then the surface RAFT polymerization of methacrylamide (MAAM) was carried out by using azobisisobutyronitrile (AIBN) as an initiator and divinylbenzene (DVB) as a cross-linker. After the removal of the embedded template, graphene oxide modified by molecularly imprinted polymers (GO-MIPs) was finally obtained. Owing to the specific imprinted cavities for 4-MEC, the satisfactory selectivity and stability of the GO-MIP nanocomposite have been demonstrated. The GO-MIP nanocomposite was then used to fabricate the electrochemical sensor, which displayed a high selectivity in detecting 4-MEC over a linear concentration range between 5 and 60 µg mL-1 with a detection limit of 0.438 µg mL-1. As a result, the GO-MIPs sensor developed an accurate, efficient, convenient, and sensitive method for public security departments to detect illicit drugs and new psychoactive substances.

IG1, a Mansonone F Analog, Exhibits Antibacterial Activity against Staphylococcus aureus by Potentially Impairing Cell Wall Synthesis and DNA Replication.

Infection caused by Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), is very common in communities and hospitals, which poses a great challenge to human health. Therefore, increasing attention has been paid to finding effective antimicrobial agents. Mansonone F is a natural compound which has an oxaphenalene skeleton and anti-S. aureus activity, but its sources are limited and its synthesis is difficult. Thus, IG1, a C9-substituent mansonone F analog, was assessed for its activity against Staphylococcus aureus and its mechanism of action was investigated. Antimicrobial susceptibility assays showed that IG1 has strong antibacterial activity against S. aureus, including MRSA, with minimum inhibitory concentrations (MICs) ranging from 0.5 to 2 µg/mL, which were very close to those of vancomycin, and these changed little, even with an increase in the amount of the inoculum. To further explore the antibacterial properties of IG1, time-kill experiments were conducted. Compared with vancomycin and moxifloxacin, treatment with different concentrations of IG1 reduced the viability of organisms in a very similar manner and the reduction was not significant, which indicated that IG1 is a potentially strong anti-S. aureus agent. Finally, the antibacterial mechanism was analyzed, with flow cytometric analysis revealing that IG1 treatment resulted in a time-dependent decrease in the DNA content of S. aureus. Transmission electron microscopy (TEM) analysis showed that very few dividing cells could be found and the cell wall was damaged in the field of IG1-treated cells. These results indicate that IG1 is a potential new antibacterial agent against S. aureus, including MRSA.

Effects of High Temperatures on the Performance of Carbon Fiber Reinforced Polymer (CFRP) Composite Cables Protected with Fire-Retardant Materials.

In this study, the safe critical temperature that can be tolerated by CFRP tendons under normal working conditions was derived through tensile tests at room and high temperatures. Next, the times required to reach a safe critical temperature for CFRP cables protected with different types of fire-retardant materials of various thicknesses were determined through fire resistance tests, Finally, fitting the surface of the finite element simulation results allowed the establishment of the temperature rise calculation model of CFRP tendons under the protection of fire-retardant materials. The results showed that 300 °C can be regarded as the safe critical temperature. Both high-silica needled felt and ceramic fiber felt exhibited high fireproof performance. With an increase in the thickness of the fire-retardant material, the time for the CFRP tendon to reach the inflection point of the heating rate increased, and the safe fire resistance time increased exponentially. According to the HC temperature rise curve, the fire resistance time of CFRP tendons protected by 24 mm thick high-silica needled felt was 45 min, and that for CFRP tendons protected by 24 mm thick ceramic fiber felt was 39.5 min. Under the action of fire corresponding to the hydrocarbon temperature rise model, the safe fire resistance time of CFRP tendons protected by 45 mm high-silica needled felt or 50 mm ceramic fiber felt was more than 2 h, sufficient to meet the specification. The proposed model of fire resistance performance enables the determination of the thickness of the fire resistance material required to obtain different degrees of fire resistance for CFRP cables for structural use.

Evaluation of the diagnostic and prognostic values of serum HSP90α in sepsis patients: a retrospective study.

Background: Sepsis is a serious syndrome that is caused by immune responses dysfunction and leads to high mortality. The abilities of heat shock protein 90α (HSP90α) in assessing the diagnosis and prognosis in patients with sepsis remain ill-defined to date. We conducted a study to reveal the possible clinical applications of HSP90α as biomarker for the diagnosis and prognosis in patients with sepsis. Methods: In total, 150 patients of sepsis, 110 patients without sepsis admitted to ICU and 110 healthy subjects were involved in this study. The serum HSP90α contents, sequential organ failure assessment (SOFA) scores, procalcitonin (PCT), and short-term survival status of the participants were measured and compared. Logistic and linear regression models adjusting for potential confounders were used to examine the association of HSP90α with sepsis survival. Moreover, serum IL-1ß, IL-18, MIP-3α, and ENA-78 were also determined. Finally, Spearman correlation analysis was employed to reveal a possible mechanism that HSP90α contributed to the short-term deaths. Results: Serum HSP90α levels in sepsis patients were higher than those in ICU controls and healthy controls (P < 0.001), and even increased in patients who died within 28 days (P < 0.001). Logistic and linear regression models identified HSP90α was an independent risk factors for sepsis mortality. Receiver operating characteristic (ROC) analysis displayed that HSP90α had a considerable predictive performance for sepsis outcome, with an area under curve (AUC) value up to 0.79. Survival analysis demonstrated that the mortality of sepsis individuals at 28 days was positively associated with HSP90α levels, especially the levels of HSP90α were greater than 120 ng/mL (P < 0.001). Moreover, among sepsis patients, those who died had notably elevated cytokines, IL-1ß, IL-18, and chemokines, MIP-3α, ENA-78, relative to survivors. Further correlation analysis demonstrated that there was a nominally positive correlation between HSP90α and IL-1ß, IL-18, and MIP-3α. Conclusion: HSP90α is of favorable clinical significance in sepsis diagnosis and prognosis, laying a foundation for future clinical applications.

Runout tracking in gear motors using a microsensor based on all-fiber Fabry-Perot interferometry.

A novel radial runout measurement method for gear motors using a microsensor based on all-fiber Fabry-Perot interferometry is investigated. In order to achieve the fault diagnosis, in this method, a single-mode fiber is put forward as a sensor to measure radial runout of the rotating shaft. The performance of the proposed sensor has been compared to a Portable Digital Vibrometer-100 laser vibrometer for validation purposes, and the results show that the difference between them is approximately ±0.55µm.

Strength Training Characteristics of Different Loads Based on Acceleration Sensor and Finite Element Simulation.

Deep squat, bench press and hard pull are important ways for people to improve their strength. The use of sensors to measure force is rare. Measuring strength with sensors is extremely valuable for people to master the intensity of exercise to scientifically effective exercise. To this end, in this paper, we used a real-time wireless motion capture and mechanical evaluation system of the wearable sensor to measure the dynamic characteristics of 30 young men performing deep squat, bench press and hard pull maneuvers. The data of tibia were simulated with AnyBody 5.2 and ANSYS 19.2 to verify the authenticity. The result demonstrated that the appropriate force of the deep squat elbow joint, the hip joint and the knee joint is 40% 1RM, the appropriate force of the bench press is 40% 1RM and the appropriate force of the hard pull is 80% 1RM. The external force is the main factor of bone change. The mechanical characteristics of knee joint can be simulated after the Finite Element Analysis and the simulation of AnyBody model are verified.

Synthesis, characterization, and evaluation of selective molecularly imprinted polymers for the fast determination of synthetic cathinones.

As a kind of new psychoactive substance (NPS), synthetic cathinones have drawn great worldwide attention. In this study, molecularly imprinted polymers (MIPs), as adsorbents for the extraction and determination of 4-methyldimethcathinone (4-MDMC), were first synthesized by coprecipitation polymerization. The physicochemical analyses of MIPs were successfully performed by XRD, FTIR, FESEM and TGA techniques. Furthermore, rebinding properties of temperature and pH dependence, and selectivity and reusability tests for MIPs and non-imprinted polymers (NIPs) were performed using an ultraviolet-visible spectrometer (UV-vis). The obtained results indicate that the imprinting efficiency has strong dependence on temperature and pH, and the optimal adsorption for targets is achieved under the condition of 318 K and pH = 6.0. This means that the combination between the polymers and 4-MDMC is a strong spontaneous and endothermic process. Compared with NIPs, MIPs exhibit prominent adsorption capacity (Q e = 9.77 mg g-1, 318 K). The selectivity coefficients (k) of MIPs for 4-MDMC, methylenedioxypentedrone (ßk-MBDP), 4-ethylmethcathinone (4-EMC), methoxetamine (MXE) and tetrahydrofuranylfentanyl (THF-F) were found to be 1.70, 3.49, 7.14 and 5.82, respectively. Moreover, it was found that the adsorption equilibrium was achieved within 30 min. The aim of this work is the simple synthesis of MIPs and the optimal performance of the molecular recognition of 4-MDMC. Moreover, the synthesized MIPs can be easily regenerated and repeatedly used with negligible loss of efficiency (only 9.94% loss after six times adsorption-desorption tests). Satisfying recoveries in the range of 69.3-78.9% indicate that MIPs have good applicability for analyte removal from urine samples. Ultimately, this material shows great promise for the rapid extraction and separation of synthetic cathinones, which are dissolved in the liquid for the field of criminal sciences.

Quadrature phase detection based on an extrinsic Fabry-Pérot interferometer for vibration measurement.

A novel vibration measurement system based on a fiber-optic extrinsic Fabry-Pérot interferometer is established. Two quadrature interferometry signals are obtained in accordance with the 90° phase shift between two output arms of a 2×2 fiber coupler. This outcome drastically simplifies the processing of collected data because only a single arctangent operation is needed to calculate the wrapped phase. Repetitive test results show that the relative micro-vibration reconstruction error of this method is less than 0.12%. This structure simplifies the extrinsic Fabry-Pérot signal demodulation process, which has guiding significance for the online measurement of high-precision physical quantities.

Secondary envelope extraction based on multiple Hilbert transforms for laser self-mixing micro-vibration measurement.

This paper presents a method that can be applied to weak feedback and full-range moderate feedback in the field of self-mixing interference measurement, and the target motion displacement can be obtained by multiple Hilbert transforms of the signal after the secondary envelope extraction. Simulations and experiments of multiple micro-vibration measurements were performed with different optical feedback factors, and the results were consistent with theoretical analysis. This method effectively eliminates the impact of the self-mixing interference signal with fringe shift on micro-vibration reconstruction.

Quadrature demodulation based on lock-in amplifier technique for self-mixing interferometry displacement sensor.

A new self-mixing interferometry quadrature demodulation method based on a lock-in amplifier technique is proposed. Sinusoidal phase modulation of the beam is obtained by an electro-optic modulator (EOM) in the external cavity. Then the real phase of the external target can be calculated by lock-in amplifier analysis method. In this paper, the validity of the proposed method is confirmed by theoretical analysis and means of simulated signals, and then it is demonstrated by several experimental measurements for target harmonic and arbitrary motion. The results show that the proposed method can get a high-precision measurement, even using a diffusive target.

Biomechanical study on side slip and forward slip promotion among children aged 3-5 years / 中国学校卫生

Objective@#To explore the forces of lower limbs during side slip and forward slip through biomechanical study, and to provide a theoretical basis for the development of lower limb movements.@*Methods@#BTS SMART DX motion capture analysis system, 8 infrared high-speed cameras, Kistler three-dimensional dynamometer, BTS FREEEMG 1000 portable wireless surface electromyography system were used to collect real-time data of side slip and forward slip. SPSS 20.0 univariate analysis of variance (ANOVA) was used to compare the differences of indicators between different groups.@*Results@#In the side sliding movement, there were significant differences in hip motion (P<0.01) between 3-year-old group and 5-year-old group, hip motion(P<0.01) between 4-year-old group and 5-year-old group, knee motion(P<0.05) and ankle motion(P<0.05) between 3-year-old group and 5-year-old group. There was a significant difference in hip motion(P<0.05) between 3-year-old group and 5-year-old group. The Fx force(P<0.01) and vertical Fy force(P<0.01) in the left and right directions of the 3-year-old group and the 5-year-old group were significantly different in the side-slip movement, while the Fx force(P<0.01) in the right and left directions of the 3-year-old group and the 5-year-old group were significantly different in the forward-slip movement, and the vertical Fy force(P<0.05) was significantly different. There were significant differences in the long head of biceps femoris, gastrocnemius and anterior tibial muscle between 3-year-old group and 5-year-old group (P<0.05). There were significant differences in the middle gluteal muscle, gracilis muscle, adductor magnus, pubic muscle, medial femoral muscle and soleus muscle between 3-year-old group and 5-year-old group (P<0.05). There was significant difference in the anterior tibial muscle (P<0.05) between the 3-year-old group and the 5-year-old group in the supporting stage, and significant difference in the gastrocnemius muscle(P<0.05) during the swing stage. There was significant difference in the anterior tibial muscle(P<0.05) between the 3-year-old group and the 5-year-old group in the swing stage.@*Conclusion@#The development of side slip and forward slip in children aged 3 to 5 years old showed that the results suggest motor development increases significantly with age among preschoolers. Rhythmic movements of side slip and forward slip should be selected in the critical period of children’s movement development at different ages, laying the foundation for good physical and mental development.

Validation of spot urine in predicting 24-h sodium excretion at the individual level.

Background: Evidence for the effect of dietary sodium intake on the risk of cardiovascular disease has been controversial. One of the main explanations for the conflicting results lies in the great variability associated with measurement methods for sodium intake. Spot urine collection is a convenient method commonly used for sodium estimation, but its validity for predicting 24-h urinary sodium excretion at the individual level has not been well evaluated among the general population.Objective: The aim of this study was to evaluate the validity of the Kawasaki, the International Cooperative Study on Salt, Other Factors, and Blood Pressure (INTERSALT), and the Tanaka formulas in predicting 24-h urinary sodium excretion by using spot urine samples in Chinese adults.Design: We analyzed the relative and absolute differences and misclassification at the individual level from 3 commonly used methods for estimating sodium intake among 141 Chinese community residents.Results: The mean measured 24-h sodium excretion was 220.8 mmol/d. The median (95% CIs) differences between measured sodium and those estimated from the Kawasaki, INTERSALT, and Tanaka methods were 6.4 mmol/d (-17.5, 36.8 mmol/d), -67.3 mmol/d (-96.5, -46.9 mmol/d), and -42.9 mmol/d (-59.1, -24.8 mmol/d), respectively. The proportions of relative differences >40% with the Kawasaki, INTERSALT, and Tanaka methods were 31.2%, 41.1%, and 22.0%, respectively; and the absolute difference for the 3 methods was >51.3 mmol/d (3 g salt) in approximately half of the participants. The misclassification rate was 63.1% for the Kawasaki method, 78.7% for the INTERSALT method, and 66.0% for the Tanaka method at the individual level.Conclusion: The results from our study do not support the use of spot urine to estimate 24-h urinary sodium excretion at the individual level because of its poor performance with respect to misclassification. This trial was registered at www.chictr.org.cn as ChiCTR-IOR-16010278.