Cross-sectional Area Research Articles

Investigating the nano-bubbles aggregation in two-phase systems: A molecular dynamics study

These days, understanding the nano-bubble aggregation has attracted lot of attentions in various fields from medicine to industries. In the present work, by means of molecular dynamics simulation, effects of surface conditions on nano-bubbles aggregation in two-phase systems have been studied. Hence, in the argon two-phase system, two heat sources have been installed on a Pt substrate and their distance has been changed: From the first to seventh system, the gap between these two surface-mounted heat sources is 46.80, 39.90, 31.20, 24.30, 23.40, 11.70, and 00.00 Å, respectively. Corresponding to the simulation results, the effect of the number of heat sources and their distances on the individual-bubbles growth rate is quite evident: whatever the spacing between two adjacent heats are smaller, the formed nano-bubbles are more stable or larger as well, and have longer lifespan.Besides, according to the calculation of the changes in quantities of the bubble contact angle (CA/deg.), size (H/Å), diameter of the cross-section area (L/Å), and thickness of the outer layer (A/Å), it was observed that each of these nano-bubbles, which have the same formation conditions and exist simultaneously in the equilibrium system, behave differently.Interestingly, by reducing the distance between the two sources in the range of 31.20–11.70 Å, owing to the existence of a film layer of vapor molecules between two neighboring nano-bubbles, the bubbles aggregation phenomena occur. At last, if the gap between the heat two sources becomes zero, an ultra-stable nano-bubble, which will has the largest size, lifetime and stability, is observed.

Evaluation of the Effects of Orthopedic Treatment on the Dentofacial Structure and Upper Airway of Subjects with Skeletal Class III Malocclusion.

The present study aimed to evaluate the effect of rapid maxillary expansion (RME) and face mask treatment on the upper airway in patients with maxillary retrusion in two dimensions using digital cephalograms and volumetric evaluation using acoustic rhinometric measurements. A total of 22 individuals with a concave profile and skeletal and dental Class III malocclusion during growth and development with a mean age of 9.9±1.38 years were included in the study. A bonded RME appliance and a petit face mask were adapted for the patients. Before treatment (T0) and after maxillary protraction (T1), lateral cephalometric films and acoustic rhinometric recordings were obtained. The dependent sample t-test was used for statistical evaluation. Cephalometric analysis revealed forward movement of the maxilla and backward downward rotation of the mandible. A significant increase was observed in the nasopharyngeal and oropharyngeal regions of the upper airway. Three-dimensional evaluation of the upper airway by acoustic rhinometry revealed only an increase in the volumes of the left nasal cavity after decongestant administration. A statistically significant increase in acoustic rhinometric measurements in nasal valves. When the correlation of the cephalometric findings of the nasopharyngeal region with the acoustic rhinometry findings was examined, no statistically significant relationship was found. As a result of this study, we observed an increase in the cephalometric measurements of the nasopharyngeal and oropharyngeal areas. A significant increase was observed in the minimal cross-sectional area measured by acoustic rhinometry.

Parametric optimization of SIP connection geometry in CFS-MRF structures: A finite element study

The structural buildings should be designed to resist both static and dynamic loads. There are different types of structural systems that can support seismic loads. Moment-resisting frames (MRFs) are widely used for seismic purposes, relying on the plastic deformations occurring between the beam and column. The main problems of cold-formed steel sections in MRFs during seismic loads are premature local and distortional buckling, which cause severe damage under strong earthquakes, such as early loss of connection strength, low ductility, and low energy dissipation. This paper clarifies the performance of the CFS section with steel interconnected part (SIP) in moment-resisting frames (MRFs) in many aspects using finite element (FE) procedures. The study summarizes the required dimensions of SIP to achieve optimal behavior for the beam-column connection. Additionally, an advanced connection consisting of SIP and four pairs of out-of-plane stiffeners has been examined. The locations of the out-of-plane stiffeners have been carefully selected to stabilize the connection. A cantilever beam connection has been used to represent an MRF in an advanced way. The connection consists of 2 C channel back-to-back beams connected with a through plate with sixteen bolts. Numerical models have been developed and verified with experimental tests under both monotonic and cyclic loading. The characteristics and creation of the numerical model are well illustrated in this paper. Cyclic loading has been applied according to AISC protocol, which is used to test the performance of the steel connections, as well as to classify the connection according to different design codes. The results show that increasing the plastic moment capacity of the CFS section decreases the required SIP dimensions to achieve optimal behavior by the connection. Additionally, it has been found that using out-of-plane stiffeners in particular locations with SIP increases energy dissipation on average by 74 %. Using stiffeners with SIP can upgrade the classification of the connection from an ordinary or intermediate moment connection to a special moment connection without the need to increase the CFS cross-section area or reduce the slenderness ratio, which in turn reduces the overall costs of construction.

Effect of Fibroblast Growth Factor (FGF) 19 and 21 on Hip Geometry and Strength in Post-menopausal Osteoporosis (PMO).

Fibroblast Growth Factor (FGF) receptor signalling is important for skeletal development. The FGF19 subfamily which includes FGF19 and FGF21 are involved in bone metabolism, although their effects on bone mineral density (BMD) and bone strength remain unclear. To further characterise the influence of these two factors on the skeleton, we studied the association between circulating concentrations of FGF19 and 21 with BMD and parameters of hip geometry and strength in post-menopausal osteoporosis (PMO). The study cohort consisted of 374 women aged (mean [SD]) 68.7[12.3] years with PMO. FGF19 and FGF21 were measured in serum by ELISA. BMD was measured at the lumbar spine (LS), total hip (TH) and femoral neck (FN) (n = 277) by dual energy X-ray absorptiometry (DXA) and hip structural analysis (HSA) parameters (n = 263) at the narrow neck of the femur (NN), Intertrochanter (IT) and Femoral shaft (FS) were derived from DXA scans. FGF19 and 21 were not associated with prevalent fractures or BMD when corrected for covariates; age, BMI, smoking habits and alcohol intake. Log-transformed FGF 21 was negatively associated with HSA parameters including Outer Diameter (OD) (p = 0.019), Cross-sectional area (CSA) (p = 0.01), cross-sectional moment of inertia (CSMI) (p = 0.011), Section modulus (Z) (p = 0.002) and cortical thickness (Co Th) (p = 0.026) at the IT only. CSA, CSMI, Z and Co Th were significantly lower (p < 0.05) in women with FGF21 concentrations greater than the median (> 103.5pg/ml). Our data suggest that FGF 21 may have potentially adverse effects on the skeleton. Further characterisation is needed, particularly as FGF 21 analogues or agonists may be used to treat obesity-related metabolic disorders.

Assessment of Energy Recovery Potential in Urban Underground Utility Tunnels: A Case Study

Underground spaces contain abundant geothermal energy, which can be recovered for building ventilation, reducing energy consumption. However, current research lacks a comprehensive quantitative assessment of its energy recovery. This research evaluates the energy recovery potential of the Xingfu Forest Belt Urban Underground Utility Tunnels. Field experiments revealed a 7 °C temperature difference in winter and a 2.5 °C reduction during the summer-to-autumn transition. A computational fluid dynamics (CFD) model was developed to assess the impact of design and operational factors such as air exchange rates on outlet temperatures and heat exchange efficiency. The results indicate that at an air change rate of 0.5 h−1, the tunnel outlet temperature dropped by 10.5 °C. A 200 m tunnel transferred 8.7 × 1010 J of heat over 30 days, and a 6 m × 6 m cross-sectional area achieved 1.1 × 1011 J of total heat transfer. Increasing the air exchange rate and cross-sectional area reduces the inlet–outlet temperature difference while enhancing heat transfer capacity. However, the optimal buried depth should not exceed 8 m due to cost and safety considerations. This study demonstrates the potential of shallow geothermal energy as an eco-friendly and efficient solution for enhancing building ventilation systems.

Long-Term Effects and Impressions of Minimal Footwear in Older Adults

Introduction: Foot pathologies can lead to difficulty walking and falls in older adults. Intrinsic foot muscles contribute to the structural support and alignment of the foot and provide somatosensory input from the ground. Minimally cushioned footwear may naturally strengthen intrinsic foot muscles and enhance sensory input to the foot; however, these effects are largely unknown in older adults. Further, there is little evidence regarding the prescription of minimal footwear and the perceptions of this footwear by older adults. Methods: Twenty-four adults age ≥65 volunteered to use minimal footwear for prescribed times during daily activities for 16 weeks. The cross-sectional area (CSA) of 5 intrinsic foot muscles was measured using ultrasound imaging at baseline, 8 weeks, and 16 weeks. Semi-structured interviews were recorded regarding participants’ impressions of the footwear, the progressive wear schedule, the footwear’s effects on orthopedic-related pain, balance, and foot awareness/sensation. Results: Across the cohort, there was no significant difference in CSA of the 5 muscles after 16 weeks of minimal footwear use. Thirteen participants had clinically meaningful increased CSA of the abductor hallucis muscle (Abh). These positive responders had no significant differences in age, grip strength, foot structure, or fall risk scores compared to participants with little to no CSA change. Interview results indicated a generally positive experience with minimal footwear for 68.1% of the cohort. A large percentage of the cohort reported no difficulty with the progressive wear schedule (77.2%), no aggravation of preexisting conditions and no new pain (77.2%), improved balance (63.6%), and improved foot awareness/sensation (72.7%) with minimal footwear use. The progressive wear schedule was perceived as inconvenient by some in the first few weeks (22.8%), but resulted in mild to no adverse effects when followed as prescribed. Conclusion: Sixteen weeks of progressive minimal footwear use in older adults did not lead to changes in intrinsic foot muscle CSA; however, half of the cohort had clinically meaningful increased CSA in the Abh muscle. It is unclear what individual qualities were associated with this positive response. Older adults reported generally positive experiences with minimal footwear with self-reported improvements in balance and foot awareness/sensation. The wear schedule may have been too conservative or not long enough to produce foot muscle hypertrophy, but subjective reports suggest beneficial neuromuscular adaptations and sensory changes occurred. Future research may need a greater length of time and larger samples to further determine the effects of long-term minimal footwear use in older adults.

Airway Tapering in Chronic Obstructive Pulmonary Disease.

Luminal narrowing is a hallmark feature of airway remodeling in COPD, but current measures focus on airway wall remodeling. Quantification of the natural increase in cumulative cross-sectional area along the length of the human airway tree can facilitate assessment of airway narrowing. We analysed the airway trees of 7641 subjects enrolled in the multicenter COPDGene cohort. Airway luminal tapering was assessed by estimating the slope of the change in cumulative cross-sectional area along the length of the airway tree over successive generations (T-Slope). We performed multivariable regression analyses to test the associations between T-Slope and lung function, St. George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) dyspnea score, 6-minute walk distance (6 MWD), FEV1 change, exacerbations, and all-cause mortality after adjusting for demographics, %CT emphysema, and total airway count. The T-Slope decreased with increasing COPD severity: 2.69 (0.70) in nonsmokers and 2.33 (0.70), 2.11 (0.65), 1.78 (0.58), 1.60 (0.53), and 1.57 (0.52) in GOLD stages 0 through 4 respectively (Jonckheere-Terpstra p=0.04). On multivariable analyses, the T-Slope was independently associated with FEV1 (β=0.13 L, 95% CI 0.10 to 0.15, p<0.001), 6MWD (β=15.0 m, 95%CI 10.8 to 19.2, p<0.001), change in FEV1 (β=-4.50 ml·year-1, 95% CI -7.32 to -1.67; p=0.001), exacerbations (IRR=0.78, 95% CI 0.73 to 0.83, p<0.001), and mortality (HR=0.79, 95% CI 0.72 to 0.86, p<0.001). T-Slope is a measure of airway luminal remodeling and is associated with respiratory morbidity and mortality.

Sarcopenia Predicts the Development of Early Adjacent Segment Disease After Transforaminal Lumbar Interbody Fusion.

Predicting the development of adjacent segment disease (ASD) after lumbar spine fusion would help guide preoperative and postoperative therapies to prevent reoperation. We sought to evaluate whether sarcopenia predicts the development of early ASD after transforaminal lumbar interbody fusion (TLIF). Retrospective data were collected from 109 patients who underwent TLIF from 2013 to 2023. Patients older than 18 years who underwent elective posterior midline approach TLIF were included. Patients with prior lumbar instrumented fusions, cases of trauma, central nervous system infection, cancer, or long-construct thoracolumbar deformity corrections and those who lacked sufficient follow-up were excluded. The primary outcome was radiographic ASD development within 3 years of surgery. Psoas volumetric measurements were recorded from the most recent preoperative MRI. Odds ratios were calculated with logistic regression analyses. In 109 patients undergoing elective TLIF, 22 (20.2%) developed ASD within 3 years. Gender, body mass index, and extent of surgery were not associated with ASD development. Multivariate analysis showed left/right psoas cross-sectional area, and psoas:vertebral body ratio (P:VBR) predicted early ASD (P < .0001). Sarcopenia was further categorized as having bilateral P:VBR ≥1 SD below gender mean (T-score -1). Of 18 sarcopenic patients, 15 developed early ASD (83.33%) vs 7 of 91 nonsarcopenic patients (7.69%; P < .0001). Postoperative mismatch between pelvic incidence and lumbar lordosis was predictive of ASD on univariate (P = .0480) but not multivariate analysis. Pelvic tilt and lumbar lordosis postoperatively were not associated with early ASD. Sarcopenia, measured by decreased psoas area and P:VBR, predicts ASD formation within 3 years of surgery. Morphometric analysis of psoas size is a simple tool to identify patients at risk of developing ASD. This information can potentially guide preoperative and postoperative therapies, affect surgical decision making, and effectively counsel patients on risks of reoperation.

Reconsidering assumptions in the analysis of muscle fibre cross-sectional area.

Cross-sectional area (CSA) is a fundamental variable in characterizing muscle mechanical properties. Typically, the CSA of a single muscle fibre is assessed by measuring either one or two diameters, and assuming the cross-section is either circular or elliptical in shape. However, fibre cross-sections have irregular shapes. The accuracy and precision of CSAs determined using circular and elliptical shape assumptions are unclear for mammalian skinned muscle fibres. Second harmonic generation imaging of skinned rabbit soleus fibres revealed that the circular assumption overstated real CSA by 5.3±25.9% whereas the elliptical assumption overstated real CSA by 2.8±6.9%. A preferred rotational alignment can bias the circular assumption, as real CSA was overstated by 22.1±24.8% when using the large diameter and understated by 11.4±13% when using the small diameter. With 73% lower variable error and reduced bias, the elliptical assumption is superior to the circular assumption when assessing the CSA of skinned mammalian fibres.

Fine Structural Analysis of Degummed Fibroin Fibers Reveals Its Superior Mechanical Capabilities.

Bombyx mori silk fibroin fibers constitute a class of protein building blocks capable of functionalization and reprocessing into various material formats. The properties of these fibers are typically affected by the intense thermal treatments needed to remove the sericin gum coating layer. Additionally, their mechanical characteristics are often misinterpreted by assuming the asymmetrical cross-sectional area (CSA) as a perfect circle. The thermal treatments impact not only the mechanics of the degummed fibroin fibers, but also the structural configuration of the resolubilized protein, thereby limiting the performance of the resulting silk-based materials. To mitigate these limitations, we explored varying alkali conditions at low temperatures for surface treatment, effectively removing the sericin gum layer while preserving the molecular structure of the fibroin protein, thus, maintaining the hierarchical integrity of the exposed fibroin microfiber core. The precise determination of the initial CSA of the asymmetrical silk fibers led to a comprehensive analysis of their mechanical properties. Our findings indicate that the alkali surface treatment raised the Young's modulus and tensile strength, by increasing the extent of the fibers' crystallinity, by approximately 40 % and 50 %, respectively, without compromising their strain. Furthermore, we have shown that this treatment facilitated further production of high-purity soluble silk protein with rheological and self-assembly characteristics comparable to those of native silk feedstock, initially stored in the animal's silk gland. The developed approaches benefits both the development of silk-based materials with tailored properties and the proper mechanical characterization of asymmetrical fibrous biological materials made of natural building blocks.

Study on microwave ablation temperature prediction model based on grayscale ultrasound texture and machine learning.

Temperature prediction is crucial in the clinical ablation treatment of liver cancer, as it can be used to estimate the coagulation zone of microwave ablation. Experiments were conducted on 83 fresh ex vivo porcine liver tissues at two ablation powers of 15 W and 20 W. Ultrasound grayscale images and temperature data from multiple sampling points were collected. The machine learning method of random forests was used to train the selected texture features, obtaining temperature prediction models for sampling points and the entire ultrasound imaging area. The accuracy of the algorithm was assessed by measuring the area of the hyperechoic area in the porcine liver tissue cross-section and ultrasound grayscale images. The model exhibited a high degree of accuracy in temperature prediction and the identification of coagulation zone. Within the test sets for the 15 W and 20 W power groups, the average absolute error for temperature prediction was 1.14°C and 4.73°C, respectively. Notably, the model's accuracy in measuring the area of coagulation was higher than that of traditional ultrasonic grey-scale imaging, with error ratios of 0.402 and 0.182 for the respective power groups. Additionally, the model can filter out texture features with a high correlation to temperature, providing a certain degree of interpretability. The temperature prediction model proposed in this study can be applied to temperature monitoring and coagulation zone range assessment in microwave ablation.

Transcriptomic Study of Different Stages of Development in the Testis of Sheep

Numerous genes govern male reproduction, modulating testicular development and spermatogenesis. Our study leveraged RNA-Seq to explore candidate genes and pivotal pathways influencing fecundity in an F1 hybrid of Southdown × Hu sheep testes across four developmental milestones: M0 (0 months old, newborn), M3 (3 months old, sexually immature), M6 (6 months old, sexually mature), and Y1 (1 years old, adult). Histological examination using hematoxylins and eosin staining revealed that the cross-sectional area of the spermatid tubules and the number of supportive cells increased in the other groups, as compared to the M0 group. The cross-sectional area of the vasculature and the number of supporting cells were found to be significantly increased in all other groups in comparison to the M0 group. We conducted GO and KEGG analyses of the differentially expressed genes (DEGs) in the three comparison groups and identified key pathways, including cAMP, MAPK, ECM–receptor interactions, PI3K-Akt, and FOXO signaling, which are closely related to testicular development and spermatogenesis. Notably, alternative splicing (AS) events were markedly elevated in M6 and Y1 stages. Key genes like GATA4, GATA6, SMAD4, SOX9, YAP1, ITGB1 and MAPK1 emerged as significantly enriched in these pathways, potentially orchestrating the transition from immature to mature testes in sheep. These findings offer valuable insights into male reproductive potential and can inform strategies for optimizing animal breeding.

Comparative efficacy of pharmaceutical (Ibuprofen) and non-pharmaceutical (photobiomodulation, and chewing gum) interventions for pain reduction after elastomeric separator placement in orthodontic patients: a randomized clinical trial.

This study compared the efficacy of pharmaceutical (ibuprofen) and non-pharmaceutical (photobiomodulation and chewing gum) interventions for pain reduction after elastomeric separator placement in orthodontic patients. This 3-arm, parallel-group randomized clinical trial was conducted on 90 orthodontic patients. The level of anxiety and pain threshold of patients were measured at baseline using the Pain Catastrophizing Scale (PCS) and an algometer, respectively. The patients were randomly assigned to three groups (n = 30; equal number of males and females). In the laser group, 940nm diode laser (Epic X, Biolase, USA, 12.35J/cm2 energy density and 300 mW power in continuous-wave mode., The cross-sectional area of the laser handpiece tip was 1.7 cm2.) was irradiated to the buccal and lingual surfaces for 35s each, prior to placement of separators. In the gum group, the patients were asked to chew a piece of sugar-free gum immediately after the placement of separators and repeat every 8h for 5min for one week in case of pain. In the ibuprofen group, patients received 400mg ibuprofen (Hakim Pharmaceuticals, Tehran, Iran) after the placement of separators and were asked to take one tablet every 8h for one week in case of pain. The pain score was recorded using the Modified McGill Pain Questionnaire (MPQ). The normality of data distribution was analyzed by the Kolmogorov-Smirnov test. ANOVA was applied to compare age, and the Chi-square and Monte Carlo Chi-square tests were used to compare gender and patient responses to the questions among the groups. Repeated measures ANOVA was used to compare the pain score at different time points and among the three groups. All statistical analyses were conducted using SPSS version 19 (SPSS Inc., Chicago, IL, USA) at 0.05 level of significance. Data analysis in this study had an intention to treat approach. Although the pain score was slightly lower in ibuprofen and gum groups, the difference among the three groups was not statistically significant (P > 0.05). 'Repeated measures ANOVA showed no significant effect of method of pain reduction on pain score (F = 1.520, P = 0.225). Time had a significant effect on pain score (F = 20.310, P < 0.001). The interaction effect of time and pain reduction method on pain score was not significant (F = 0.737, P = 0.651). patients experienced a lower level of pain in the ibuprofen and chewing gum groups, the difference in pain score was not significant among the three groups (P = 0.225). patients experienced a higher level of pain at 12 and 24 hours after the placement of separators in all groups. Considering the comparably equal analgesic efficacy of this modalities, non-pharmaceutical interventions can be used for pain reduction of elastomeric separator. The study protocol was registered in the Iranian Registry of Clinical Trials (IRCT20210927052611N1). Date of registration 2022/03/14.

Mathematical Model of Drilling Mud Movement along a Shale Shaker Screen

Introduction. When drilling oil or gas wells, rock from the bottomhole is brought to the surface by drilling mud, which is cleaned of sludge by shale shakers at the first stage. Shale shakers are equipped with such a screen and create such trajectories of vibration of the frame in order to solve a dual problem: on the one hand, to provide the cleaning of the drilling mud coming from the well mouth, and on the other hand — to maintain the proper degree of cleaning. To correctly select the nomenclature of screens, it is necessary to reliably determine the throughput capacity of a shale shaker in the real-time setting. This will allow you to pre-order the required number of screens with the required cell size. Previously, studies were conducted by sieving a mixture of calibrated granules on a standard shaker or by straining mineral oil through a fixed screen. However, this does not fully correspond to the actual conditions of drilling mud screening. The objective of this article was to simulate the throughput of a drilling shale shaker under real conditions by calculating the movement of drilling mud along a vibrating screen using its previously obtained specific throughput capacity.Materials and Methods. When creating a mathematical model of the full throughput capacity of a shale shaker, a previously known mathematical model of fluid flow in an open channel and a finite-dimensional approximation in the form of a sequence of sections of concentrated containers connected by hydraulic conductivities (by analogy with the approximation of long electrical lines and extended gas pipelines by the finite element method) were used. The fluid flow rate over the screen was determined according to Chézy law. In this case, the cross-sectional area of the flow above the screen for a specific section was specified as the arithmetic mean between the initial and final values of the drilling mud height in the corresponding section.Results. A chain calculation scheme for sieving drilling mud was compiled. Based on the material balance, mathematical models were developed for determining the throughput and height of drilling mud above the screen: for the first section of the screen and the first nodal point of the screen; for subsequent screen sections and subsequent screen nodal points; for the last section of the screen and the last nodal point of the screen.A mathematical model of the drilling mud movement along the shale shaker screen has been obtained, which, due to the finite-dimensional representation of this flow along n sections of the screen length, is a system of n integral equations describing concentrated tanks, and n – 1 algebraic equations describing the flow of drilling mud between tanks.Discussion and Conclusion. The movement of drilling mud along the length of the shale shaker screen corresponds to the movement of a steady uneven flow in an open channel. However, in the first case, the volume flow along the length is variable (decreasing to zero), and in the second case, it is constant along the length. Therefore, the use of only one differential equation for steady uneven flow in an open channel is not sufficient in this case. The resulting mathematical model of the drilling mud movement along the shale shaker screen is a mathematical basis for the development of a modeling program to determine the throughput of the shale shaker for real operating conditions, i.e., for a specific drilling mud, a given screen or a given drive system of the shale shaker.

Peripheral Nerve Injury After Deoxycholic Acid (ATX-101) Injection in an Experimental Rat Model.

Deoxycholic acid (ATX-101) is a drug administered by subcutaneous injection for local fat reduction. However, ATX-101 treatment has been reported to cause marginal mandibular nerve injury with noticeable functional deficits when targeting submental fat. As a cytolytic agent with some selectivity for adipocytes, ATX-101 may damage the lipid-rich myelin surrounding peripheral nerves. This study seeks to characterize the nerve injection injury from ATX-101 in an experimental rat model. Using a rat sciatic nerve injection model, intrafascicular and extrafascicular injections of deoxycholic acid (ATX-101) were compared to lidocaine (positive control) and saline (negative control). Nerves were harvested at a 2-week endpoint for histomorphometric analysis. Cross-sectional area of nerve injury was significantly increased by ATX-101 injection at 75±15% with intrafascicular ATX-101 (p<0.001), 41±21% with extrafascicular ATX-101 (p<0.01), and 38±20% with positive control lidocaine (p<0.01) compared to 7±13% with negative control saline. Demyelinating injury was a significant mechanism of injury in the affected nerve fibers compared to uninjured nerve fibers (p<0.04), but there was no difference in axon-to-myelin area ratio between the lidocaine and ATX-101 cohorts. After two weeks, Wallerian degeneration was evident with only small regenerating nerve fibers present in the ATX-101-injured groups compared to saline (2.54±0.26um vs 5.03±0.44um, p<0.001) in average width. Deoxycholic acid (ATX-101) is capable of extensive nerve injury in rats. The mechanism of action for ATX-101 does not preferentially target myelin more than other common neurotoxic agents. Appropriate knowledge of surgical anatomy and injection technique is necessary for any practitioners providing ATX-101 injections.

The correlation of muscle morphology with variations of 10-repetition maximum bench press strength in resistance-trained subjects

The relationship between muscle mass and strength is complex as it can be influenced by several neurological factors. Variations in the type of training and its mechanisms involved, such as strength- or hypertrophy-oriented training, may influence this relationship in different ways (Carvalho et al., 2022). In addition, the relationship between muscle stiffness and strength remains unclear (Akagi et al., 2016; Mannarino et al., 2019). Thus, this research aimed to investigate the potential correlation between the strength levels, measured by the 10-repetition maximum (10RM), across different ranges of motion (ROM) in the barbell bench press exercise (BP) to the cross-sectional area (CSA) and shear modulus (= indication for stiffness) of the muscles primarily engaged in the exercise. Twenty-one resistance-trained participants (age 27.1 ± 3.4 years) volunteered in this study. The CSA and muscle shear modulus were assessed in a resting position with ultrasound imaging using an ultrasound system (Supersonic Imaging, Aix-en-Provence, France). CSA ultrasound images were captured with panoramic mode for the pectoralis major and the triceps brachii long head. Muscle shear modulus was measured for the pectoralis major, the anterior deltoid, and the triceps brachii long head using shear wave elastography (SWE). Additionally, participants were assessed for their 10RMs of the three types of BP variations, a full ROM and two partial ROMs, the upper half and lower half of the full movement. Data analyses revealed significant correlations between all BP variations and the medial and lateral CSA of the pectoralis major with correlations ranging from r = 0.775 to r = 0.832 (p = 0.001). Significant correlations were also found for the proximal CSA of the triceps brachii long head with the strength values of all tested BP variations with correlations ranging from ρ = 0.492 to ρ = 0.494 (p = 0.028 to p = 0.027). The distal CSA of the triceps brachii did only correlate significantly with the lower ROM BP (r = 0.484, p = 0.026). No significant correlations were found between the SWE of the measured muscles and the bench press variations tested. Additionally, no differences were observed in the correlations between the BP variations. Correlations between 10RM strength levels and the CSA of the pectoralis, and to a lesser extent, the triceps muscle, show the significance of muscle mass for strength in resistance-trained individuals. This finding aligns with a previous training study that examined the hypertrophic effects of bench press exercises on various muscles (Ogasawara et al., 2012). The study revealed that although both the pectoralis and triceps muscles increased in size, the triceps tended to plateau earlier. This suggests that the pectoralis muscle has a greater capacity for muscle volume growth and, consequently, a higher potential for force production. Finally, SWE measurements revealed no significant correlation with BP variations, implying that muscle stiffness may not play as critical a role in 10RM performance as muscle CSA does. This conclusion aligns with other studies that could not find significant changes in muscle stiffness using SWE following resistance training interventions (Dankel &amp; Razzano, 2020). References Akagi, R., Shikiba, T., Tanaka, J., &amp; Takahashi, H. (2016). A six-week resistance training program does not change shear modulus of the triceps brachii. Journal of Applied Biomechanics, 32(4), 373–378. https://doi.org/10.1123/jab.2015-0290 Carvalho, L., Junior, R. M., Barreira, J., Schoenfeld, B. J., Orazem, J., &amp; Barroso, R. (2022). Muscle hypertrophy and strength gains after resistance training with different volume-matched loads: A systematic review and meta-analysis. Applied Physiology, Nutrition, and Metabolism, 47(4), 357–368. https://doi.org/10.1139/apnm-2021-0515 Dankel, S. J., &amp; Razzano, B. M. (2020). The impact of acute and chronic resistance exercise on muscle stiffness: A systematic review and meta-analysis. Journal of Ultrasound, 23(4), 473–480. https://doi.org/10.1007/s40477-020-00486-3 Mannarino, P., Matta, T. T. D., &amp; Oliveira, L. F. D. (2019). An 8-week resistance training protocol is effective in adapting quadriceps but not patellar tendon shear modulus measured by Shear Wave Elastography. PLoS ONE, 14(4), Article e0205782. https://doi.org/10.1371/journal.pone.0205782 Ogasawara, R., Thiebaud, R. S., Loenneke, J. P., Loftin, M., &amp; Abe, T. (2012). Time course for arm and chest muscle thickness changes following bench press training. Interventional Medicine and Applied Science, 4(4), 217–220. https://doi.org/10.1556/imas.4.2012.4.7

The therapeutic potential of red beetroot (Beta vulgaris L.) intake on muscle atrophy in immobilized mouse skeletal muscles

AbstractSkeletal muscle atrophy is the reduction in muscle mass and function caused by an imbalance in protein synthesis and degradation. Inflammation has been shown to accelerate protein degradation during periods of muscle inactivity. We investigated the potential therapeutic effects of beetroot extract (BRE) in reducing inflammation and oxidative stress to prevent muscular atrophy after a short period of immobilization. We divided 36 male BALB/c mice into three groups: control, muscular atrophy mice, and muscular atrophy mice treated with BRE (n = 12). Each group was further divided into two subgroups: (1) 7‐day immobilization and (2) 10‐day recovery. BRE was administered orally at a dose of 300 mg/kg for 17 days. We assessed the anti‐inflammatory and antioxidative effects of BRE using ELISA and RT‐PCR assays. Hematoxylin–eosin staining was used to measure the cross‐sectional area (CSA) of muscle fibers, and grip strength tests were performed to assess muscle strength. BRE administration increased muscle weight, CSA, and grip strength in mice with immobilization‐induced muscle atrophy. It also suppressed inflammation and oxidative stress biomarkers in atrophic muscle fibers. Higher nitrate levels and lower Troponin I (TnI) concentrations were observed in the BRE‐treated group, indicating improved muscle function and structure. These findings suggest that BRE may have therapeutic benefits in improving muscle mass and function and warrant further studies in humans, particularly in individuals with low physical activity levels.

Crossing cable design optimization of multi-tower cable-stayed bridge based on joint analytical method and genetic algorithm

As the length of the main span increases, the stiffness of multi tower cable-stayed bridges continues to decrease. The performance of the structure can be improved by setting crossing cables at the main span. The setting of crossing cables is a key issue in the overall design of bridges. This study presents a new optimization strategy to achieve the optimal setting of crossing cables. The developed technique combines analytical algorithm, optimization algorithm and finite element method. The anchor position, number, cross-sectional area and cable force of crossing cable are taken as variables. Firstly, an analytical algorithm is used to determine the feasible interval of the number and area of crossing cables, and then the genetic algorithm is used to search for the optimal solution within the feasible interval to obtain the crossing cable layout with minimum steel. Based on the analytical method, the feasible interval is determined, so that the population is close to the convergence point from the initial state, and the optimization efficiency is improved. The effectiveness of the proposed method is verified by four optimization problems, and the influence of the deck stiffness on the anchor position of crossing cable is discussed, which provides a reference for the setting of the crossing cables in the preliminary design stage.

Age- and size-related changes in hind limb muscles in two baboon species (Papio anubis and P. papio).

Body size has an impact on all biological functions and analyzing how body size impacts functional traits such as locomotion is critical. Body size does not only vary across species but also during ontogeny. Indeed, juvenile animals are often at a competitive disadvantage due to their smaller absolute size. Consequently, understanding size- and age-related changes in the locomotor system is critical for our understanding of adult phenotypes. Here, we address this question by exploring growth of the hind limb muscles in two species of closely related baboons that differ in their ecology, the olive baboon, Papio Anubis, the Guinea baboon, and Papio papio. To do so, we dissected 40 P. anubis and 10 P. papio and measured the mass and physiological cross-sectional area (PCSA) of the hind limb muscles. Our results showed no sexual differences in size- or age-related growth patterns, but did show differences between species. Whereas the scaling of muscle mass and PCSA was largely isometric in P. anubis, allometric scaling was more common in P. papio. Despite these differences between species, the knee extensors and external rotators at the knee scaled with positive allometry in both species highlighting their important role during adult locomotion. Although life-history data for P. papio are scarce, we suggest that differences between species may be associated with differences in adult body size and age of locomotor independence between species.

Changes in muscle cross-sectional area during two menstrual cycles may not be exclusively attributed to resistance training

This study investigated the impact of menstrual cycle (MC) phases and resistance training (RT) on muscle cross-sectional area (CSA) in two MCs utilizing a within-subject design. Twenty women with regular MCs had their legs randomly allocated to either the control (CON) or RT condition, which included 16 training sessions over two MCs. CSA, estradiol (E2), and progesterone (P4) were assessed during the menstruation (M), ovulation (O), and luteal (L) phases in the first (M1, O1, L1) and second (M2, O2, L2) MCs and at the beginning of the third MC (M3). P4 values were significantly higher during the luteal phase than during menstruation (P &lt; 0.0001) and ovulation (P &lt; 0.0001). No significant differences in E2 concentrations were observed between the MC phases (P = 0.08). For the RT condition, the CSA showed significant increases at O2, L2, and M3 compared to baseline (M1) (all P &lt; 0.0001). No significant changes were observed for the CON condition during the two MCs (P &gt; 0.05). However, RT condition showed a significant change in average CSA across two MCs. Additionally, individual analyses revealed that 19 participants showed variation in CSA above or below the minimum detectable difference during the two MCs. These findings suggest that changes in muscle CSA observed during two MCs may not be exclusively attributed to RT.