Reinforcing effects of polypropylene on energy absorption and fracturing of cement-based tailings backfill under impact loading

Polypropylene(PP)fiber-reinforced cement-based tailings backfill(FRCTB)is a green compound material with superior crack resistance and has good prospects for application in underground mining.However,FRCTB exhibits susceptibility to dynamic events,such as impact ground pressure and blast vibrations.This paper investigates the energy and crack distribution behavior of FRCTB under dynamic impact,considering the height/diameter(H/D)effect.Split Hopkinson pressure bar,industrial computed tomography scan,and scanning electron microscopy(SEM)experiments were carried out on six types of FRCTB.Laboratory outcomes confirmed fiber aggregation at the bottom of specimens.When H/D was less than 0.8,the proportion of PP fibers distributed along theθangle direction of80°-90°increased.For the total energy,all samples presented similar energy absorption,reflectance,and transmittance.However,a rise in H/D may cause a rise in the energy absorption rate of FRCTB during the peak phase.A positive correlation existed between the average strain rate and absorbed energy per unit volume.The increase in H/D resulted in a decreased crack volume fraction of FRCTB.When the H/D was greater than or equal to 0.7,the maximum crack volume fraction of FRCTB was observed close to the incidence plane.Radial cracks were present only in the FRCTB with an H/D ratio of 0.5.Samples with H/D ratios of 0.5 and 0.6 showed similar distributions of weakly and heavily damaged areas.PP fibers can limit the emergence and expansion of cracks by influencing their path.SEM observations revealed considerable differences in the bonding strengths between fibers and the FRCTB.Fibers that adhered particularly well to the substrate were attracted together with the hydration products adhering to surfaces.These results show that FRCTB is promising as a sustainable and green backfill for determining the design properties of mining with backfill.

The Influence of Carbon Nanotubes and Nano-Silica Fume on Enhancing the Damping and Mechanical Properties of Cement-Based Materials

This paper conducted experimental studies on the damping and mechanical properties of carbon nanotube-nanosilica-cement composite materials with different carbon nanotube contents. The damping and mechanical properties enhancement mechanisms were analyzed and compared through the porosity structure test, XRD analysis, and scanning electron microscope observation. The results show that the introduction of nanosilica significantly improves the dispersion of carbon nanotubes in the cement matrix. At the same time, the addition of nanosilica not only effectively reduces the critical pore size and average pore size of the cement composite material, but also exhibits good synergistic effects with carbon nanotubes, which can significantly optimize the pore structure. Finally, a rationalization suggestion for the co-doping of nanosilica and carbon nanotubes was given to achieve a significant increase in the flexural strength, compressive strength and loss factor of cement-based materials.

Copper Ions Removal from Wastewater by Electrocoagulation Using Cement-based Cathode Plates

The present work uses PEO solution to well disperse carbon fiber and identifies percolation thresholds of carbon fiber and carbon black which are used as conductive fillers.The resultant cathode plates have an average compressive strength of 27.3 MPa and flexural strength of 29.09 MPa,which demonstrate excellent mechanical properties.The Cu^(2+)removal efficiency was measured at different current densities in EC process with cement-based cathode plate,while the voltage changes were recorded.The results showed that the cement-based cathode plate operated stably and achieved 99.7%removal of 1 L of simulated wastewater with a Cu^(2+)concentration of 200 ppm at a current density of 8 m A/cm^(2)for 1 h.Characterization of floc and tested cathode plates,SEM and EDS analyses,and repeatability testing of the tested plates demonstrate the reusability of the plates,proving that cement-based plates can effectively replace metal cathode plates,reduce the cost of EC and improve the applicability of EC devices.

Experimental and Numerical Research on Water Transport during Adsorption and Desorption in Cement-Based Materials

The durability of cement-based materials is related to water transport and storage in their pore network under different humidity conditions.To understand the mechanism and characteristics of water adsorption and desorption processes from the microscopic scale,this study introduces different points of view for the pore space model generation and numerical simulation of water transport by considering the“ink-bottle”effect.On the basis of the pore structure parameters(i.e.,pore size distribution and porosity)of cement paste and mortar with water-binder ratios of 0.3,0.4 and 0.5 obtained via mercury intrusion porosimetry,randomly formed 3D pore space models are generated using two-phase transformation on Gaussian random fields and verified via image analysis method of mathematical morphology.Considering the Kelvin-Laplace equation and the influence of“ink-bottle”pores,two numerical calculation scenarios based on mathematical morphology are proposed and applied to the generated model to simulate the adsorption-desorption process.The simulated adsorption and desorption curves are close to those of the experiment,verifying the effectiveness of the developed model and methods.The obtained results characterize water transport in cement-based materials during the variation of relative humidity and further explain the hysteresis effect due to“ink-bottle”pores from the microscopic scale.

Effect of Glutinous Rice Flour on Mechanical Properties and Microstructure of Cement-based Materials

The mechanism of glutinous rice flour,a kind of natural admixture,on the hydration process,setting time,and microstructure of the Portland cement was investigated.The experimental results show that the glutinous rice flour has an obvious setting retarding effect on cement pastes.The optimal dosage of the glutinous rice flour is 3wt%.In this case,the initial and final setting time of the paste are delayed by 140 and185 min,respectively.The flexural and compressive strengths of the hardened paste are increased by 0.35%and 0.07%after 56 d of curing.The glutinous rice flour hinders the mineral dissolution process and decreases the concentration of calcium ion at the initial stage of hydration due to the complexation effect,thereby hindering the nucleation and growth of CH and C-S-H phases and prolonging the hydration process.However,C-S-H phases combine with the glutinous rice flour to contribute the bonding effect together,which compacts the microstructure of hardened cement pastes at the later hydration stage of cement pastes.Thus,in-depth investigation on the utilization of glutinous rice flour as the admixture for the Portland cement is expected to be meaningful for the control of hydration exothermic rate and setting time.

Effects of Strain Rate and Fiber Content on the Dynamic Mechanical Properties of Sisal Fiber Cement-Based Composites

In this paper,a split Hopkinson pressure bar(SHPB)was used to investigate the dynamic impact mechanical behavior of sisal fiber-reinforced cement-based composites(SFRCCs),and the microscopic damage evolution of the composites was analyzed by scanning electron microscopy(SEM)and energy-dispersive X-ray spectrome-try(EDS).The results show that the addition of sisal fibers improves the impact resistance of cement-based composite materials.Compared with ordinary cement-based composites(OCCs),the SFRCCs demonstrate higher post-peak strength,ductility,and energy absorption capacity with higher fiber content.Moreover,the SFRCCs are strain rate sensitive materials,and their peak stress,ultimate strain,and energy integrals all increase with increasing strain rate.From the perspective of fracture failure characteristics,the failure of OCCs is dominated by the brittle failure of crystal cleavage.In contrast,the failure mode of the SFRCCs changes to microscale matrix cracks,multi-scale pull-out interface debonding of fibers(fine filaments and bundles),and mechanical interlock.This research provides an experimental basis for the engineering application of high-performance and green cement-based composites.

Characteristics of Emission Non-nulling Pulsars Through Simulation

We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is detectable.For(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is non-zero.For(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the line-of-sight.We find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and 0.2.Furthermore,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.

Non-HDL-C水平和ApoB/ApoA1比值与初发心肌梗死的相关性研究

目的探究不同非高密度脂蛋白胆固醇(non-HDL-C)水平初次急性心肌梗死患者的临床特征及载脂蛋白B(Apo B)和载脂蛋白A1(Apo A1)比值以及non-HDL-C与冠状动脉(冠脉)病变程度的相关性。方法选取2021年12月至2023年4月于重庆医科大学附属第一医院心内科入院治疗的首次诊断为急性心肌梗死且行冠脉造影的患者410例。计算Apo B/Apo A1比值及non-HDL-C,根据non-HDL-C三分位数分为低non-HDL-C组(≤2.89 mmol/L)、中non-HDL-C组(2.9~4.16 mmol/L)、高non-HDL-C组(≥4.17 mmol/L),比较三组患者一般临床资料及冠脉病变特点的差异性。另采用Spearman秩相关和二元Logistics回归分析non-HDL-C水平、Apo B/Apo A1对冠脉病变严重程度的影响。结果与低non-HDL-C组相比,中non-HDL-C组和高non-HDL-C组患者年龄更小(P<0.05);高non-HDL-C组较另外两组具有更高水平的体质指数(BMI)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、ApoB、ApoA1、ApoB/ApoA1、白蛋白、γ-谷酰转移酶、尿酸(P<0.05)。三组间左前降支病变、回旋支病变、多支血管病变、Gensini评分相比,差异有统计学意义(P<0.05)。偏相关分析显示Apo B/Apo A1和non-HDL-C均与多支血管病变、Gensini评分呈正相关(P<0.05);多因素二元Logistics回归分析显示ApoB/ApoA1比值(OR=3.149,95%CI:1.209~8.201,P=0.019)、non-HDL-C≥4.17 mmol/L(OR=4.199,95%CI:1.524~11.565,P=0.006)是多支血管病变的独立危险因素。结论在初次急性心肌梗死青年患者有冠脉病变或(冠状动脉粥样硬化性心脏病)危险因素中,更应关注ApoB/ApoA1及non-HDL-C,同时严格控制non-HDL-C是心肌梗死患者潜在的降脂目标。

Progress in the Use of Glucocorticoids and Biological Agents in Non-Infectious Uveitis

One of the main immune-mediated diseases that lead to avoidable blindness is non-infectious uveitis. Glucocorticoids are the first-line therapy choice for noninfectious uveitis;however, biologics are also showing promise in the management of this condition. The description of glucocorticoid and biologic usage in non-infectious uveitis is the main topic of this paper.

Investigating Non-Compliance with COVID-19 Vaccination through Hesitancy, Refusal, and Access Limitation: A Community-Based Survey from the Democratic Republic of the Congo

Introduction: Vaccination plays a pivotal role in mitigating the repercussions of the COVID-19 pandemic. However, vaccination campaigns encounter obstacles, especially in developing countries like the Democratic Republic of the Congo (DRC). This study aimed at investigating the roles of vaccine hesitancy, refusal, and access barriers, while identifying individual-level factors associated with non-vaccination in Mbujimayi, DRC. Methods: A community-based cross-sectional survey was conducted in three health districts and included 1496 residents. Attitudes and behaviors related to seeking COVID-19 vaccination were assessed using a standardized questionnaire. Hierarchical logistic regression modeling was used to assess factors potentially affecting non-compliance with vaccination. Results: Among participants (median age = 33, IQR = 23.3, M/F sex ratio = 0.7), 60% displayed misconceptions about COVID-19 or its vaccine, while only 35.2% perceived COVID-19 as a significant health threat. Vaccination coverage was estimated at 49.1% (95% CI: 47.5;52.6), with 71.8% of vaccinated individuals having received one dose. Among the unvaccinated individuals, 50.9% expressed no intention to be vaccinated in the future, citing hesitation (30.4%) or refusal (39.6%) mainly due to side effects or distrust of vaccines. Conversely, 32.7% of the unvaccinated persons expressed access barriers despite willingness to be vaccinated. Misconceptions about COVID-19 and its vaccines were the main drivers of vaccination non-compliance. Conclusion: These findings demonstrate significant vaccine non-compliance driven by hesitancy, refusal, and access barriers. Strategies to enhance vaccination coverage and pandemic preparedness should address misconceptions, sociodemographic barriers, and geographic disparities.

The Interventional Capacity of Community Health Volunteers for Screening and Linkages of Non-Communicable Diseases in Nyeri County, Kenya

Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from May 2022 to March 2023 with 370 study participants. Multistage cluster and random sampling were used to select ten community units, and therefore, 150 CHVs were chosen for the control unit, and 150 were used to form the interventional group. Data was collected from the KOBO app. Six (6) homogenous FGDs comprised ten members, and 10 KII were conducted across study sites. Quantitative data was analyzed using SPSS version 28.0, and qualitative data was audio-recorded, transcribed, and analyzed via N-Vivo 12. The study shows that 59.3% of respondents have minimal information, and 92.7% (n = 139) have no clear understanding of NCDs, with a pre-intervention capacity of 48.8%. Independent sample t-test showed a significant difference in capacity from a pre-intervention average of 48.75 (SD ± 5.7)%, which increased to 68.28 (SD ± 7.6)%, p < 0.001. A well-designed community interventional model plays a pivotal role in grassroots healthcare delivery but requires optimization for NCD management.

Primary Non-Hodgkin’s Malignant Lymphoma of the Uterus at the Reference Hospital of Maradi/Niger: A Case Report

Malignant non-Hodgkins lymphoma (MHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass in a 50-year-old patient with no previous history of the disease. It was classified as Ann Arbor IV Bb after imaging, given the medullary infiltration and signs of clinical and biological evolutivity: the patient had received two courses of chemotherapy, CHOP protocol. She died 23 days after the second treatment due to a hypertensive crisis.

Roles of Community Pharmacists in Screening and Disseminating of Information about Non-Steroidal Anti-Inflammatory Drugs Risks: Implications for Drug Safety Assessment

Background: The increasing use of non-steroidal anti-inflammatory drugs (NSAIDs) both on prescription and over the counter raises a major global health concern because of the risks associated with their use if no proper guidance is given by the health care provider. This study assessed the roles of community pharmacists in screening and disseminating information about the risks associated with NSAID use in Zambia. Methodology: This was a national cross-sectional study in which a structured self-administered questionnaire was administered to 245 registered community pharmacists in Zambia. Stata/BE, version 15.1 (Stata Corporation, College Station, Texas, USA) and multivariate logistic regression model was used to determine factors associated with information dissemination about ADRs of NS-NSAIDs. Results: 231 of the 245 distributed questionnaires were returned giving a response rate of 94.3%. All (100%) participating community pharmacists claimed to have practiced dispensing NSAIDs. However, only 26 (11.0%) and 71 (30.8%) regularly screened for risk factor of selective COX-2 NSAIDS (SC2-NSAIDS) and non-selective NSAIDS (NS-NSAIDs) respectively. Information dissemination on adverse drug reactions (ADRs) of SC2-NSAIDS was regularly provided by only 22 (9.5%) of pharmacists while that of NS-NSAIDs was regularly provided by 49 (21.2%). In the multivariate logistic regression model, being the owner of a pharmacy (AOR: 5.4, CI: 1.84 - 16.4) was significantly associated with information dissemination about ADRs of NS-NSAIDs while an hour increase in the working hours per day (AOR: 0.9, CI: 0.64 - 0.95) was associated with less likelihood of information dissemination. Conclusion: Pharmacists working in community pharmacies in Zambia did not regularly screen and disseminate information about the risks associated with NSAID use. Therefore, pharmacists should be able to screen and monitor patients at risk and be aware of the majority of risk factors while dispensing NSAIDs to minimize the associated complications.

A Study on Near-Infrared Non-Invasive Blood Glucose Concentration Regression Prediction Based on PSO-MKL-SVR

To improve the accuracy of predicting non-invasive blood glucose concentration in the near-infrared spectrum, we utilized the Particle Swarm Optimization (PSO) algorithm to optimize hyperparameters for the Multi-Kernel Learning Support Vector Machine (MKL-SVR). With these optimized hyperparameters, we established a non-invasive blood glucose regression model, referred to as the PSO-MKL-SVR model. Subsequently, we conducted a comparative analysis between the PSO-MKL-SVR model and the PSO-SVR model. In a dataset comprising ten volunteers, the PSO-MKL-SVR model exhibited significant precision improvements, including a 16.03% reduction in Mean Square Error and a 0.29% increase in the Squared Correlation Coefficient. Moreover, there was a 0.14% higher probability of the Clark’s Error Grid Analysis falling within Zone A. Additionally, the PSO-MKL-SVR model demonstrated a faster operational speed compared to the PSO-SVR model.

Progress in the Study of Inflammatory Bowel Disease Patients with Primary Non-Responsiveness

Inflammatory bowel disease (IBD) is a group of chronic, nonspecific intestinal inflammatory disorders characterized by localized and systemic inflammation. The use of biologic agents in the treatment of IBD patients is widespread, and the occurrence of primary non-responsiveness during treatment is also significant. This review briefly summarizes the possible reasons for primary non-responsiveness in IBD patients, as well as predictive markers and current strategies to address it, providing a theoretical reference for early identification and management of IBD patients who do not respond to treatment.

Assessment of Barriers and Challenges to the Screening and Linkages of Non-Communicable Diseases by Community Health Volunteers in Nyeri County, Kenya

Non-communicable diseases (NCDs) are a significant global health challenge, contributing to 50% of worldwide morbidity and 63% of mortality. The burden is particularly substantial in low—and middle-income countries (LMICs), where 80% of NCD-related deaths occur. A quasi-experimental study addressed this challenge from May 2022 to March 2023. This study utilized a non-equivalent pre-and post-test design, with 300 participants in the quantitative and 70 in the qualitative. The study employed multistage cluster and random sampling to select ten community units, resulting in 150 community health volunteers (CHVs) in the control unit and 150 in the intervention group. Data collection was facilitated through the KOBO app. Qualitative data analysis involved six homogeneous focus group discussions (FGDs) and ten key informant interviews (KIIs), audio-recorded, transcribed, and analyzed using N-Vivo 12. Despite efforts to implement screening programs and improve linkages to care, significant barriers persist. This article reviews these barriers, drawing on current literature and empirical evidence. Key obstacles identified include limited awareness, inadequate healthcare infrastructure, cultural beliefs, financial constraints, fragmented healthcare systems, and challenges linking individuals to appropriate care services. The article explores strategies to overcome these barriers, emphasizing the importance of collaborative approaches involving stakeholders at various levels. Addressing these challenges aims to strengthen NCD screening and linkages to care, ultimately improving health outcomes for populations globally. Several recommendations emerge from the study’s findings and literature review. Raising awareness about NCDs and preventive measures is crucial and can be achieved through targeted health education campaigns and community outreach programs. Addressing healthcare infrastructure deficiencies, such as inadequate facilities and workforce shortages, is essential to ensure access to quality care. Cultural beliefs and practices also play a significant role in shaping health-seeking behavior. Engaging with local communities and incorporating cultural sensitivity into healthcare delivery can help bridge the gap between traditional beliefs and modern healthcare practices. Financial constraints pose a significant barrier to healthcare services, particularly in LMICs. Innovative financing mechanisms, such as health insurance schemes or subsidies, can help alleviate this burden and improve access to care. Furthermore, the fragmented nature of healthcare systems can hinder effective NCD management. Enhancing coordination and integration between primary care providers, specialists, and community health workers is essential to ensure seamless care delivery and patient follow-up. Finally, strengthening linkages between screening programs and care services is critical for the timely diagnosis and management of NCDs. This requires establishing robust referral systems and ensuring continuity of care for patients throughout their healthcare journey. In conclusion, addressing the multifaceted barriers to NCD screening and care linkage is essential for improving health outcomes globally. By implementing targeted interventions and fostering collaboration among stakeholders, progress can be made towards reducing the burden of NCDs and promoting population health.

Pang Fuwan Uses Yao Medicine to Observe the Therapeutic Effects on the Physical and Mental Symptoms of Patients with Advanced Non-Small Cell Lung Cancer

Objective: Investigate the efficacy and safety of Yao Medicine in the treatment of advanced non-small-cell lung carcinoma, and explore the best therapeutic measure for clinical benefit. Methods: From July 2020 to July 2022, 84 patients with advanced non-small-cell lung carcinoma were selected and randomly divided into the Observation Group and control group, and the control group was treated with routine Western medicine, with 42 cases in each group. The activity of daily living (ADL) was assessed before and after treatment, meanwhile, the self-rating depression scale (SDS) and self-rating anxiety SAS (SAS) were used to assess the improvement of a bad mood, and quality of life SF-36 was used to assess the quality of life, to judge the efficacy and safety. Results: The effective rate of observation group was 91.67%. The effective rate of the control group was 76.19%. The effective rate of the observation group was significantly higher than that of the control group (P 0.05). There were no significant differences in the scores of SDS, SAS and quality of life between the two groups before treatment (P > 0.05), and after treatment, the scores of SDS, SAS and quality of life in the two groups were compared with those in the control group (P > 0.05), the scores of VAS, SDS and SAS decreased significantly, while ESCV, angle of straight leg elevation, ADL, physiological score, emotional score, social score and health status score increased significantly, the difference was statistically significant (P 0.05). Conclusion: Yao Medicine can improve the psychosomatic symptoms of patients with advanced non-small-cell lung carcinoma better, with better efficacy and higher safety.

Influence of Non-Natural Ageing Temperature on the Microstructural Characteristics and Mechanical Properties of Cast Aluminum 6063 Alloy

This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 Tm) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 Tm) and 160?C (0.24 Tm), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm2. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample.

Advances in the Research Application of Ultrasound Non-Invasive Stress-Strain Loop Technology in Cardiovascular Diseases

The ultrasound pressure-strain loop (PSL) technique is a non-invasive method of examining myocardial work, which takes into account the effect of cardiac afterload on deformation and combines the overall longitudinal strain force of the left ventricle with the changes in the left ventricular pressure, allowing earlier detection of possible subclinical cardiac damage in patients, and a more accurate and non-invasive assessment of the patient’s myocardial work performance. In this article, we will discuss the progress of PSL applications in cardiovascular diseases.

TyG指数、RC及NonHDL-C与急性冠脉综合征血管病变严重程度的相关性研究

目的探讨非高密度脂蛋白胆固醇(NonHDL-C)、甘油三酯葡萄糖指数(TyG指数)及残余脂蛋白胆固醇(RC)水平与急性冠脉综合征(ACS)冠状动脉血管病变严重程度的相关性。方法选取我院收治的147例经PCI术治疗的ACS患者作为研究对象。收集患者的基线资料,并使用Gensini评分评估冠状动脉病变的严重程度。依据Gensini评分,将患者分轻度组(4≤Gensini评分≤16,n=52)和中重度组(Gensini评分>16,n=95)。采用多因素Logistic回归分析确定ACS患者血管病变严重程度的独立危险因素。采用Spearman相关分析评估RC、NonHDL-C和TyG指数水平与Gensini评分的相关性,并通过ROC曲线评估RC、TyG指数及NonHDL-C水平对ACS患者血管病变严重程度的预测价值。结果中重度组与轻度组相比,NonHDL-C、RC和TyG指数水平均显著增加(P<0.05)。多因素Logistic回归分析结果显示,RC(OR=7.673,P=0.012)、TyG指数(OR=2.537,P=0.013)和NonHDL-C(OR=2.144,P=0.001)水平是ACS患者冠状动脉病变严重程度的独立危险因素。RC、TyG指数、NonHDL-C水平的AUC为0.653、0.671、0.711。TyG指数与NonHDL-C水平的联合AUC为0.739。Spearman相关分析结果显示:Gensini评分与TyG指数、RC和NonHDL-C水平呈正相关(P<0.05)。结论RC、TyG指数和NonHDL-C的水平升高可能是ACS患者冠状动脉病变严重程度的危险因素,并对日后的血管病变严重程度有一定的预测价值。