Development of a RPA-CRISPR/Cas12a based rapid visual detection assay for Porcine Parvovirus 7.

Introduction: Porcine Parvovirus (PPV) is a significant pathogen in the pig industry, with eight genotypes, including PPV7, identified since its emergence in 2016. Co-infections with viruses such as Porcine Circovirus 2 (PCV2) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) pose serious risks to swine health. Thus, there is an urgent need for rapid, sensitive, and specific detection methods suitable for use in field settings or laboratories with limited resources. Methods: We developed a CRISPR/Cas12a-based assay combined with recombinase polymerase amplification (RPA) for the rapid detection of PPV7. Specific RPA primers and five CRISPR RNAs (crRNAs) were designed to target a highly conserved region within the NS1 gene of PPV7. Optimization of crRNA and single-stranded DNA (ssDNA) concentrations was performed to enhance the assay's performance. Results: CrRNA optimization identified crRNA-05 as the optimal candidate for Cas12a-based detection of PPV7, as all synthesized crRNAs demonstrated similar performance. The optimal crRNA concentration was determined to be 200 nM, yielding consistent results across tested concentrations. For ssDNA optimization, the strongest fluorescence signal was achieved with 500 nM of the FAM-BHQ ssDNA receptor. The assay showed a minimal detection limit of 100copies/µl for PPV7, confirmed through fluorescence and lateral flow detection methods. Specificity testing indicated that only PPV7 DNA samples returned positive results, confirming the assay's accuracy. In tests of 50 lung tissue samples from diseased pigs, the RPA-Cas12a assay identified 29 positive samples (58%), surpassing the 22 positive samples (44%) detected by conventional PCR. This highlights the RPA-Cas12a method's enhanced detection capability and its potential utility in clinical surveillance and management of PPV7 in swine populations. Discussion: The RPA-Cas12a assay effectively detects PPV7 in clinical samples, enhancing disease surveillance and control in pigs. Its adaptability to resource-limited settings significantly improves PPV7 management and prevention strategies, thereby supporting the overall health and development of the pig industry.

Exploration of the mechanism underlying the therapeutic effect of electroacupuncture at chengshan acupoint on post-hemorrhoidectomy anal pain: Insights from the mAChRs/IP3-Ca2+-CaM signaling pathway.

OBJECTIVE: In the context of postoperative anal pain, understanding the intricate mechanisms and effective interventions is paramount. This study investigates the role of Muscarinic Acetylcholine Receptors (mAChRs) and the IP3-Ca2+-CaM signaling pathway in a rat model of postoperative anal pain, exploring the potential analgesic effects of electroacupuncture. METHODS: Comprehensive approaches involving mechanical sensitivity assays, Western blotting, immunohistochemistry, and intracellular calcium concentration measurement were used. RESULTS: The authors found elevated mAChRs expression in the postoperative pain model. Antagonizing mAChRs reduced pain sensitivity and attenuated the IP3-Ca2+-CaM pathway. Remarkably, electroacupuncture treatment further mitigated pain, potentially by suppressing this signaling cascade. INTERPRETATION: These findings reveal a novel connection between mAChRs and the IP3-Ca2+-CaM pathway in postoperative anal pain and suggest electroacupuncture as a promising avenue for pain relief through these mechanisms, offering insights into innovative strategies for postoperative pain management.

Deep insights into the assembly mechanisms, co-occurrence patterns, and functional roles of microbial community in wastewater treatment plants.

The understanding of activated sludge microbial status and roles is imperative for improving and enhancing the performance of wastewater treatment plants (WWTPs). In this study, we conducted a deep analysis of activated sludge microbial communities across five compartments (inflow, effluent, and aerobic, anoxic, anaerobic tanks) over temporal scales, employing high-throughput sequencing of 16S rRNA amplicons and metagenome data. Clearly discernible seasonal patterns, exhibiting cyclic variations, were observed in microbial diversity, assembly, co-occurrence network, and metabolic functions. Notably, summer samples exhibited higher α-diversity and were distinctly separated from winter samples. Our analysis revealed that microbial community assembly is influenced by both stochastic processes (66%) and deterministic processes (34%), with winter samples demonstrating more random assembly compared to summer. Co-occurrence patterns were predominantly mutualistic, with over 96% positive correlations, and summer networks were more organized than those in winter. These variations were significantly correlated with temperature, total phosphorus and sludge volume index. However, no significant differences were found among microbial community across five compartments in terms of ß diversity. A core community of keystone taxa was identified, playing key roles in eight nitrogen and eleven phosphorus cycling pathways. Understanding the assembly mechanisms, co-occurrence patterns, and functional roles of microbial communities is essential for the design and optimization of biotechnological treatment processes in WWTPs.

Correlation of lower limb alignment with medial mensical extrusion in knee osteoarthritis.

BACKGROUND: This study aims to explore the relationship between Lower limb alignment parameters and the degree of Medial Meniscal Extrusion (MME) in patients with Knee Osteoarthritis (KOA), in hopes of providing new reference data for the prevention and treatment of KOA. METHODS: A retrospective study design was employed, analyzing 623 KOA patients treated at our hospital from 2022 to 2023, with 307 patients' information collected according to inclusion and exclusion criteria. Patients were divided into mild and severe groups based on the degree of MME, and differences in Lower limb alignment parameters between the two groups were compared. Univariate analysis, Pearson correlation analysis, and multivariate stepwise regression analysis were used, along with Receiver operating characteristic(ROC) curve assessment to evaluate the predictive value of Lower limb alignment parameters on the degree of MME. RESULTS: Univariate analysis showed significant correlations between Anatomic Mechanical Axis (AMA), Joint Line Convergence Angle (JLCA), mechanical Lateral Distal Femur Angle (mLDFA), Medial Proximal Tibia Angle (MPTA), and the degree of MME (P < 0.05). Pearson correlation analysis further confirmed the positive correlations between these parameters and the degree of MME. Multivariate stepwise regression analysis indicated that AMA, JLCA, and mLDFA are significant independent predictors of the severity of MME. ROC analysis suggested that the combination of AMA, JLCA, and mLDFA could better predict severe MME. CONCLUSION: AMA, JLCA, and mLDFA are closely related to the degree of MME in KOA patients and can serve as important parameters for assessing the severity of MME, holding significant implications for the early prevention and treatment of KOA.

Overexpression of Basonuclin Zinc Finger Protein 2 in stromal cell is related to mesenchymal phenotype and immunosuppression of mucinous colorectal adenocarcinoma.

BACKGROUND: Mucinous carcinoma (MC) is a distinct histologic subtype of colorectal cancer (CRC) that is less studied and associated with poor prognosis. This study aimed to identify MC-specific therapeutic targets and biomarkers to improve the prognosis of this aggressive disease. METHODS: CRC samples from The Cancer Genome Atlas (TCGA) were categorized into MC and non-MC (NMC) groups based on histologic type. A multi-scale embedded gene co-expression network analysis (MEGENA) was constructed to identify gene modules associated with the MC group. The potential functions of Basonuclin Zinc Finger Protein 2 (BNC2) were further analyzed using the Biomarker Exploration for Solid Tumors (BEST) database. In vivo and in vitro experiments were conducted to validate the predicted results. RESULTS: We identified the stromal component-related gene, BNC2, in the MC population. This gene is associated with a shorter progression-free interval (PFI) in CRC patients. BNC2 promotes FAP (encoding Fibroblast Activation Protein Alpha) transcription in cancer-associated fibroblasts (CAFs) and is involved in angiogenesis through two pathways. Additionally, BNC2 enhances tumor cell invasiveness in a CAF-dependent manner. Patients with high BNC2 expression benefited less from immunotherapy compared to those with low BNC2 expression. CONCLUSIONS: Our study highlights the clinical importance of BNC2 in MC, and targeting BNC2 on stromal cells (fibroblasts and endothelial cells) may be an effective strategy for treating MC.

A retrospective analysis of spinal teratomas and spinal lipomas: overlaps and differences in presentation, surgical treatments, and outcomes.

BACKGROUND: Spinal teratomas and lipomas, both adult and pediatric cases, are rare diseases with many similarities, but have yet to be systematically compared. PURPOSE: To systematically compare spinal teratomas and lipomas to optimize management. STUDY DESIGN: Retrospective. PATIENT SAMPLE: Symptomatic spinal teratoma and lipoma patients surgically treated at our center. OUTCOME MEASURES: Anatomical distribution, clinical manifestations, resection status, and outcomes. METHODS: Spinal teratoma and lipoma patients with complete data treated during 2008 to 2023 in our center were enrolled. Electrophysiological monitoring was routinely performed after 2012. Patient characteristics, anatomical distribution, clinical manifestations, surgical resection, and outcomes were analyzed. RESULTS: We enrolled 86 teratoma patients (71 adults) and 51 lipoma patients (39 adults). Most tumors were lumbosacral lesions; cervical/thoracic involvement was more common with lipomas. Pain, the most frequent manifestation, was more common in teratomas. Gross total resection (GTR) was achieved in 51.1% and 49% of teratomas and lipomas, respectively. Electrophysiological monitoring increased the GTR rate from 38.8% to 48.6%. Age independently predicted (OR: 1.040, 95% CI: 1.008-1.078) GTR/near-total resection (NTR). Symptom relief occurred in 81.4% teratoma patients and 64.7% lipoma patients. Recurrence/symptomatic progression occurred in 19 teratomas and 7 lipomas after a median of 95 and 115 months, respectively. Adult lipoma patients without spinal dysraphism had lower recurrence rates. GTR (HR: 0.172, 95% CI: 0.02557-0.7028) and lesion length (HR: 1.351, 95% CI: 1.138-1.607) independently predicted recurrence/progression. CONCLUSIONS: GTR should be pursued for adult/pediatric spinal teratomas and pediatric spinal lipomas. For adult spinal lipoma patients without dysraphism, conservative surgery could be considered.

Dominant role of soil iron and organic matters in arsenic transfer from soil to plant in a mine area in Hunan Province, Central China.

The transfer of arsenic (As) from soil to plant could be significantly influenced by soil parameters through regulating soil As bioavailability. To distinguish the bioavailable As provided by soil and the As uptaken by plants, herein two different soil bioavailable were defined, namely potential soil bioavailable As (evaluated through the bioavailable fraction of As) and actual soil bioavailable As (assessed through plant bioaccumulation factor, BF, and BFavailable). To identify the dominant soil parameters for the two soil bioavailable As forms, soil and plant samples were collected from a former As mine site. The results showed that the potential bioavailable As only accounted for 1.77 to 11.43% in the sampled soils, while the BF and BFavailable in the sampled vegetables ranged from 0.00 to 1.01 and 0.01 to 17.87, respectively. Despite a similar proportion of As in the residual fraction, soil with higher pH and organic matter (OM) content and lower iron (Fe) content showed a higher potential soil bioavailable As. Correlation analysis indicated a relationship between the soil pH and potential soil bioavailable As (r = 0.543, p < 0.01) and between the soil Fe and actual soil bioavailable As (r = - 0.644, p < 0.05, r = - 0.594, p < 0.05). Stepwise multiple linear regression (SMLR) analysis was employed to identify the dominant soil parameters and showed that soil pH and phosphorus (P) content could be used to predict the potential soil bioavailable As (R2 = 0.69, p < 0.001). On the other hand, soil Fe and OM could be used to predict the actual soil bioavailable As (R2 = 0.18-0.86, p < 0.001-0.015, in different vegetables). These results suggest that different soil parameters affect potential and actual soil bioavailable As. Hence, soil Fe and OM are the most important parameters controlling As transfer from soil to plant in the investigated area.

Effect of onion skin powder on color, lipid, and protein oxidative stability of premade beef patty during cold storage.

The impact of premade beef patty (BBP) with red onion skin powder (OSP) at 0, 1, 2, and 3% levels on color, lipid, and protein oxidative stability, and infection degree of microorganisms during cold storage was investigated. The objective was to determine the effect of color by L*, a*, b*, and the content of MetMb. The inhibitory effect of OSP on the oxidation of lipid and protein was studied based on TBARS and the carbonyl content of protein in samples at different storage times. TVB-N content was used to characterize the degree of infection of microorganisms and their effect on meat quality. The results showed that the addition of OSP reduced the pH, L *, a*, and b * values of BBP, and improved the hardness, springiness, gumminess, and cohesiveness of BBP, but had no significant effect on the chewiness of BBP (p > 0.05). After 12 days of storage, the carbonyl group and TBARS content in the BBP supplemented with 3%OSP was significantly lower than that in the control group (p < 0.05). Furthermore, the addition of OSP significantly inhibited the TVB-N increase during beef patty storage. These results indicated that OSP has a good research prospect as a natural antioxidant or preservative.

Triclosan exposure causes abnormal bile acid metabolism through IL-1ß-NF-κB-Fxr signaling pathway.

Triclosan (TCS) is an eminent antibacterial agent. However, extensive usage causes potential health risks like hepatotoxicity, intestinal damage, kidney injury, etc. Existing studies suggested that TCS would disrupt bile acid (BA) enterohepatic circulation, but its toxic mechanism remains unclear. Hence, the current study established an 8-week TCS exposure model to explore its potential toxic mechanism. The results discovered 8 weeks consecutive administration of TCS induced distinct programmed cell death, inflammatory cell activation and recruitment, and excessive BA accumulation in liver. Furthermore, the expression of BA synthesis and transport associated genes were significantly dysregulated upon TCS treatment. Additional mechanism exploration revealed that Fxr inhibition induced by TCS would be the leading cause for unusual BA biosynthesis and transport. Subsequent Fxr up-stream investigation uncovered TCS exposure caused pyroptosis and its associated IL-1ß would be the reason for Fxr reduction mediated by NF-κB. NF-κB blocking by dimethylaminoparthenolide ameliorated TCS induced BA disorder which confirmed the contribution of NF-κB in Fxr repression. To sum up, our findings conclud TCS-caused BA disorder is attributed to Fxr inhibition, which is regulated by the IL-1ß-NF-κB signaling pathway. Hence, we suggest Fxr would be a potential target for abnormal BA stimulated by TCS and its analogs.

The impact of toe spring and foot strike angle on forefoot running biomechanics: a finite element analysis.

The surge in popularity of running has led to a multitude of designs in running shoe technology, notably, there is an increasing trend in toe spring elevation. However, the impact of this design on foot structures during running remains an essential exploration. To investigate the effects of toe spring on the foot during forefoot running, we employed finite element simulation to create two sole models with different toe spring heights (6.5 cm and 8 cm) and ground contact angles (5°, 10°, and 15°). We established and validated two foot-shoe coupling models and compared stress variations in metatarsal bones and the big toe under identical loading and environmental conditions. Higher toe spring resulted in lower peak stress and reduced stress concentration in metatarsal bones. The fourth and fifth metatarsals exhibited increasing stress trends with ground contact angle, with the fifth metatarsal experiencing the most significant stress concentration. In the case of low toe spring, stress on the fifth metatarsal increased from 15.917 MPa (5°) to 27.791 MPa (15°), indicating a rise of 11.874 MPa. Conversely, the first metatarsal showed lower stress, indicating relative safety but reduced functional significance. Moreover, higher toe spring running shoes exerted less pressure on the big toe, with an increasing trend in stress on the big toe with an increase in ground contact angle. Shoes with a higher toe spring design result in reduced pressure on the big toe. Therefore, it is advisable to avoid landing angles greater than 15° to prevent stress fractures resulting from repetitive loading.

The association between dietary zinc intake and osteopenia, osteoporosis in patients with rheumatoid arthritis.

BACKGROUND: Diet has been shown to be associated with rheumatoid arthritis (RA), of which osteoporosis is the most common and important complication, and zinc has been shown to inhibit the inflammatory response, but studies on the relationship between dietary zinc and osteoporosis in patients with RA are limited and inconclusive. In this study, we aimed to explore the relationship between dietary zinc intake and osteoporosis or osteopenia in patients with RA. METHODS: Data on RA patients were derived from the National Health and Nutrition Examination Survey (NHANES) 2007 to 2010, 2013 to 2014, and 2017 to 2020. Weighted univariate and multivariate logistic regression models were performed to explore the association between dietary zinc intake and osteoporosis or osteopenia in RA patients. The relationship was further investigated in different age, body mass index (BMI), nonsteroidal use, dyslipidemia, diabetes, and hypertension population. All results were presented as odds ratios (ORs) and confidence intervals (CIs). RESULTS: In total, 905 RA patients aged ≥ 40 years were included. After adjusting all covariates, higher dietary zinc intake was associated with lower odds of osteopenia or osteoporosis (OR = 0.39, 95%CI: 0.18-0.86) in RA patients. The relationship between dietary zinc intake ≥ 19.52 mg and lower odds of osteopenia or osteoporosis were also found in those aged ≥ 60 years (OR = 0.38, 95%CI: 0.16-0.91), BMI normal or underweight (OR = 0.16, 95%CI: 0.03-0.84), nonsteroidal use (OR = 0.14, 95%CI: 0.02-0.82), dyslipidemia (OR = 0.40, 95%CI: 0.17-0.92), diabetes (OR = 0.37, 95%CI: 0.14-0.95), and hypertension (OR = 0.37, 95%CI: 0.16-0.86). CONCLUSION: Higher dietary zinc intake was associated with reduced incidence of osteopenia or osteoporosis in patients with RA. Further longitudinal and randomized trials are necessary to validate our findings and explore the underling mechanisms. Adequate dietary zinc intake may beneficial to the bone health in RA patients.

Equol exerts anti-tumor effects on choriocarcinoma cells by promoting TRIM21-mediated ubiquitination of ANXA2.

Choriocarcinoma is a malignant cancer that belongs to gestational trophoblastic neoplasia (GTN). Herein, serum metabolomic analysis was performed on 29 GTN patients and 30 healthy individuals to characterize the metabolic variations during GTN progression. Ultimately 24 differential metabolites (DMs) were identified, of which, Equol was down-regulated in GTN patients, whose VIP score is the 3rd highest among the 24 DMs. As an intestinal metabolite of daidzein, the anticancer potential of Equol has been demonstrated in multiple cancers, but not choriocarcinoma. Hence, human choriocarcinoma cell lines JEG-3 and Bewo were used and JEG-3-derived subcutaneous xenograft models were developed to assess the effect of Equol on choriocarcinoma. The results suggested that Equol treatment effectively suppressed choriocarcinoma cell proliferation, induced cell apoptosis, and reduced tumorigenesis. Label-free quantitative proteomics showed that 136 proteins were significantly affected by Equol and 20 proteins were enriched in Gene Ontology terms linked to protein degradation. Tripartite motif containing 21 (TRIM21), a E3 ubiquitin ligase, was up-regulated by Equol. Equol-induced effects on choriocarcinoma cells could be reversed by TRIM21 inhibition. Annexin A2 (ANXA2) interacted with TRIM21 and its ubiquitination was modulated by TRIM21. We found that TRIM21 was responsible for proteasome-mediated degradation of ANXA2 induced by Equol, and the inhibitory effects of Equol on the malignant behaviors of choriocarcinoma cells were realized by TRIM21-mediated down-regulation of ANXA2. Moreover, ß-catenin activation was inhibited by Equol, which also depended on TRIM21-mediated down-regulation of ANXA2. Taken together, Equol may be a novel candidate for the treatment for choriocarcinoma.

All-aqueous synthesis of alginate complexed with fibrillated protein microcapsules for membrane-bounded culture of tumor spheroids.

Water-in-water (W/W) emulsions provide bio-compatible all-aqueous compartments for artificial patterning and assembly of living cells. Successful entrapment of cells within a W/W emulsion via the formation of semipermeable capsules is a prerequisite for regulating on the size, shape, and architecture of cell aggregates. However, the high permeability and instability of the W/W interface, restricting the assembly of stable capsules, pose a fundamental challenge for cell entrapment. The current study addresses this problem by synthesizing multi-armed protein fibrils and controlling their assembly at the W/W interface. The multi-armed protein fibrils, also known as 'fibril clusters', were prepared by cross-linking lysozyme fibrils with multi-arm polyethylene glycol (PEG) via click chemistry. Compared to linear-structured fibrils, fibril clusters are strongly adsorbed at the W/W interface, forming an interconnected meshwork that better stabilizes the W/W emulsion. Moreover, when fibril clusters are complexed with alginate, the hybrid microcapsules demonstrate excellent mechanical robustness, semi-permeability, cytocompatibility and biodegradability. These advantages enable the encapsulation, entrapment and long-term culture of tumor spheroids, with great promise for applications for anti-cancer drug screening, tumor disease modeling, and tissue repair engineering.

Quantitative prediction of water quality in Dongjiang Lake watershed based on LUCC.

Land Use/ Cover Change (LUCC) plays a crucial role in influencing hydrological processes, nutrient cycling, and sediment transport in watersheds, ultimately impacting water quality on both spatial and temporal scales. Accurately predicting changes in watershed water quality is beneficial for the sustainable management of water resources. Current models often lack the ability to effectively predict water quality changes in a dynamic spatio-temporal context, particularly in complex watershed environments. The overall purpose of the study is to establish a comprehensive and dynamic modeling framework that links LUCC with water quality, allowing for accurate predictions of future water quality under varying land use scenarios. The model, which uses water quality as the dependent variable and LUCC as the independent variable, was developed to quantitatively predict changes in watershed water quality. To achieve this, annual multi-period remote sensing images from Landsat-5, Landsat-8 or Sentinel-2 satellites spanning from 1992 to 2022 were analyzed. Random Forest (achieving a Kappa coefficient of 0.9468) were employed to classify land use within the watershed. Based on classification results, a Cellular Automata-Markov chain model (CA-Markov) was constructed to simulate and predict the spatio-temporal patterns of land use, incorporating driving factors such as proximity to water systems, roads, elevation, and slope. Validation of the model using LUCC data from 2020 yielded a high prediction accuracy with a Kappa coefficient of 0.9505. The CA-Markov model was further utilized to project LUCC under three different scenarios-natural development, ecological protection, and arable land protection-between 2023 and 2033. Based on these projections, the coupled water quality and LUCC model was employed to predict water quality changes in the watershed over the same period. Key findings indicate that water quality is likely to improve under ecological protection scenario, while deterioration is expected under natural development scenario and cropland protection scenario due to urban expansion, agricultural practices, and water diversion for irrigation. This study provides a robust framework for watershed management, offering scientific guidance for source management and water purification efforts, thereby contributing significantly to the sustainable development of water resources.

Almost Sure Stability and Stabilization of Composite Switched Systems With Persistent Dwell Time Constraint.

This article is devoted to the exponential almost sure (EAS) stability and stabilization of continuous-time composite switched systems (CSSs) by employing a novel dual-switching mechanism, which incorporates both persistent dwell time (PDT) switching and a set of Markov processes. The interrelation between the parameters under the PDT constraint is established by ensuring that switching frequency remains within the maximum permissible range, which serves as a pivotal consideration in the stability analysis of CSSs subject to above-mentioned dual-switching mechanism. Furthermore, the sufficient conditions for achieving EAS-stability and stabilization of CSSs are established with the designed switching strategy. Our results, in contrast to previous works that are special cases of our study, are more general and less conservative. Three examples are presented to validate the developed theoretical results.

Maxillary impacted canine replacing a central incisor with root resorption: Multidisciplinary treatment in a preadolescent patient.

Maxillary canines are often impacted, which can result in tooth disorders and adversely affect occlusal and facial development. The case report describes complete bilateral impaction of maxillary canines and significant root resorption of a central incisor. The multidisciplinary approach is the optimal strategy for addressing impacted maxillary canines.

Constructing Targeted Strong Nb4d-O2p-Li2s Configurations to Obtain Excellent Energy Density and Long Life for Li-rich Cathodes.

The Li-rich Mn-based cathode materials (LMRs) deliver excellent energy density and exhibit low cost, which are considered as the most promising cathode materials for the next generation lithium-ion batteries. However, the irreversible redox reaction of the oxygen atoms directly leads to release oxygen and intensifies phase transformation. Besides, the local stress and strain will be generated due to the unit-cell volume difference between R-3m and C2/m phases, which continuously aggravates the collapse of secondary particles. Herein, the strong Nb4d-O2p-Li2s configurations at the Li1 sites of the TM-layer in the C2/m phase and secondary particles with the radial arrangement of refined primary particles are designed to inhibit oxygen release and relieve lattice stress by Nb2O5 treatment. Meanwhile, the preferential growth of the active {010} planes is presented to obtain an excellent transmission rate of Li+. As a result, the designed LMR delivers remarkable electrochemical properties with high discharge capacity and initial coulomb efficiency of 276 mA h g-1 and 85% at 0.1 C, outstanding cycling retention rate of 81% after 300 cycles. This novel crystal structure combining oxygen coordination regulation and micro-nano scale design provides inspiration for the design of high-performance LMRs.

Biomechanical Study of Symmetric Bending and Lifting Behavior in Weightlifter with Lumbar L4-L5 Disc Herniation and Physiological Straightening Using Finite Element Simulation.

BACKGROUND: Physiological curvature changes of the lumbar spine and disc herniation can cause abnormal biomechanical responses of the lumbar spine. Finite element (FE) studies on special weightlifter models are limited, yet understanding stress in damaged lumbar spines is crucial for preventing and rehabilitating lumbar diseases. This study analyzes the biomechanical responses of a weightlifter with lumbar straightening and L4-L5 disc herniation during symmetric bending and lifting to optimize training and rehabilitation. METHODS: Based on the weightlifter's computed tomography (CT) data, an FE lumbar spine model (L1-L5) was established. The model included normal intervertebral discs (IVDs), vertebral endplates, ligaments, and a degenerated L4-L5 disc. The bending angle was set to 45°, and weights of 15 kg, 20 kg, and 25 kg were used. The flexion moment for lifting these weights was theoretically calculated. The model was tilted at 45° in Abaqus 2021 (Dassault Systèmes Simulia Corp., Johnston, RI, USA), with L5 constrained in all six degrees of freedom. A vertical load equivalent to the weightlifter's body mass and the calculated flexion moments were applied to L1 to simulate the weightlifter's bending and lifting behavior. Biomechanical responses within the lumbar spine were then analyzed. RESULTS: The displacement and range of motion (ROM) of the lumbar spine were similar under all three loading conditions. The flexion degree increased with the load, while extension remained unchanged. Right-side movement and bending showed minimal change, with slightly more right rotation. Stress distribution trends were similar across loads, primarily concentrated in the vertebral body, increasing with load. Maximum stress occurred at the anterior inferior margin of L5, with significant stress at the posterior joints, ligaments, and spinous processes. The posterior L5 and margins of L1 and L5 experienced high stress. The degenerated L4-L5 IVD showed stress concentration on its edges, with significant stress also on L3-L4 IVD. Stress distribution in the lumbar spine was uneven. CONCLUSIONS: Our findings highlight the impact on spinal biomechanics and suggest reducing anisotropic loading and being cautious of loaded flexion positions affecting posterior joints, IVDs, and vertebrae. This study offers valuable insights for the rehabilitation and treatment of similar patients.

Negative Emotions Are Associated With Older Self-perceived Age: A Cross-section Study From the UK Biobank.

BACKGROUND: Prior research has indicated a potential connection between psychological stress and how individuals perceive their own age. Building on this foundation, the current study explores the relationship between negative emotions and self-perceived age. METHODS: We conducted a cross-sectional analysis using data from the UK Biobank, a comprehensive cohort study representing the UK population. The analysis included 347 892 participants, aged between 39 and 73 years, of which 184 765 were women, accounting for 53.1% of the sample. Participants were categorized into three groups based on their self-perceived age: feeling younger than their chronological age (group Younger), feeling older than their chronological age (group Older), and feeling as old as their actual age (group Same). To investigate the relationship between negative emotions and self-perceived age, we utilized a multinomial logistic regression model with the Younger group serving as the reference category. RESULTS: Of 347 892 participants, after adjusted for covariates, the results showed that participants with irritability, nervous feelings, worrier/anxious feelings or fed-up feelings, worry too long and loneliness/isolation are more likely to be rated as "about your age" or "older than you are," with "younger than you are" as the reference group, indicating that negative emotions may influence one's self-perceived age. Among those negative emotions, irritability has the most significant impact self-perceived age, with the odds ratios (ORs) being 1.44 (95% CI: 1.35-1.54) and 1.11 (95% CI: 1.09-1.14). CONCLUSION: Negative emotions are associated with older self-perceived age, and irritability has the greatest impact. Further studies analyzing self-perceived age are needed to take psychological factors into consideration.

Combination of magnetite and sodium percarbonate to enhance acetate-enriched short-chain fatty acids production during sludge anaerobic fermentation.

Large amounts of waste activated sludge are generated daily worldwide, posing significant environmental challenges. Anaerobic fermentation is a promising method for sludge disposal, but it has two technical bottlenecks: the availability of short-chain fatty acids (SCFAs)-producing substrates and SCFAs consumption by methanogenesis. This study proposes a pretreatment strategy combining sodium percarbonate (SPC) and magnetite (Fe3O4) to address these issues. Under optimized conditions (20 mg Fe3O4/g TSS and 15 mg SPC/g TSS), SCFAs production increased to 3244.10 ± 216.31 mg COD/L, about 3.06 times the control (1057.29 ± 35.06 mg COD/L) and surpassing reported treatments. The combined pretreatment enhanced the disruption of extracellular polymeric substances, increased the release of biodegradable matters, improved acidogenesis enzyme activities, and inhibited methanogenesis. Additionally, it increased NH4+-N release in favor of the recovery of phosphorus from sludge residual. This study demonstrates an efficient pretreatment for high SCFAs production and resource recovery from WAS.