Stratified structure of membrane clogs observed in full scale cross-flow tubular ultrafiltration (UF) system: Fouling characterization and a proposed two-stage formation mechanism.

Membrane fouling remains a significant challenge in wastewater treatment, hindering both efficiency and lifespan. This study reports a distinct phenomenon of stratified membrane clogging observed in a full-scale cross-flow tubular ultrafiltration (UF) system treating sludge anaerobic digestion (AD) reject water. The distinct stratified structure, comprising inner and outer layers within the cake layer, has not been previously described. This research involved characterizing the filtration performance, analyzing membrane clog composition, and proposing a two-stage formation mechanism for the stratified clogs. It was revealed that higher inorganic and lower organic content in the outer layer compared to the inner layer. Acid and alkali treatments demonstrated the effectiveness of combined cleaning strategies. A mathematical model was developed to determine the critical conditions for stratified clog formation, influenced by membrane flux and cross-flow velocity (CFV). It is proposed that outer layer forms through long-term selective deposition, while the inner layer results from short-term dewatering within limited tubular space. High CFV (>2.5 m/s) prevents inner layer formation. Critical conditions for stratification occur at a flux of 18 L/m2/h with a CFV of 0.1 m/s or 65 L/m2/h with a CFV of 0.35 m/s. This study contributes a novel understanding of stratified membrane clogging, proposing a two-stage formation mechanism and identifying critical conditions, which provides insights for effective fouling control strategies and maintenance of operational efficiency for membrane systems.

Sex-related differences in the load-velocity and load-power relationships of the decline bench press exercise.

The purpose of this study was to analyse the load-velocity and load-power relationships of the decline bench press exercise (DBPE) and to compare sex-related differences. Twelve young healthy men and women performed a progressive loading test for the determination of 1RM strength and individual load-velocity and load-power relationship in the DBPE. A very close relationship between mean propulsive velocity (MPV) and %1RM was observed (R2 = 0.94). This relationship improved when plotting data separately by sex (R2 = 0.96-97). Individual load-velocity profiles gave an R2 = 0.99 ± 0.01. The relationship between mean propulsive power (MPP) and %1RM was R2 = 0.23. When separating data by sex, R2 = 0.64-73 were obtained. Individual load-power profiles gave an R2 of 0.93 ± 0.07. Significant sex-related differences were found for MPV, with males having faster velocities than females from 30% to 40% 1RM (p = 0.01) and for MPP, with males having greater MPP (W) than females from 30% to 95% 1RM (p < 0.001). The results of this study show that a strong correlation exists between relative load and MPV/MPP in the DBPE, allowing the possibility of using one to predict the other with great precision, especially when a sex-specific equation is used.

Subcutaneous advanced glycation end products, cardiovascular risk factors and vascular health during childhood development in a Swiss population.

Background: Skin-derived advanced glycation end products (sAGEs) have been associated with cardiovascular (CV) risk and mortality in adults. We hypothesize that cardiorespiratory fitness (CRF), body mass index (BMI) and vascular health are associated with development of sAGEs during childhood. Methods: In our prospective cohort study, 1171 children aged 6-8 years were screened for sAGEs, BMI, retinal arteriolar diameters (CRAE) and pulse wave velocity (PWV), using standardized procedures. To determine CRF a 20 m shuttle run was performed. After four 4 years, all parameters were assessed in 675 children using the same protocols. Results: Higher initial CRF levels were significantly associated with lower sAGEs (ß [95 CI] -0.02 [-0.03 to -0.002] au, p = 0.022) levels at follow-up, although they showed a greater change from baseline to follow-up (ß [95 CI] 0.02 [0.002 to 0.03] au, p = 0.027). Moreover, individuals with higher sAGEs at baseline showed narrower CRAE (ß [95% CI] -5.42 [-8.76 to -2.08] µm, p = 0.001) at follow-up and showed a greater change in CRAE (ß [95% CI] -3.99 [-7.03 to -0.96] µm, p = 0.010) from baseline to follow-up. Conclusion: Exercise and higher CRF may help mitigate the formation of AGEs during childhood, thereby reducing the risk for development of CV disease associated with AGEs-induced damage. Preventive strategies may need to target CRF early in life to achieve improvement of CV risk factors and may counteract the development of CV disease later in life.

Velocity of cerebrospinal fluid in the aqueduct measured by phase-contrast MRI in rat.

Cerebrospinal fluid (CSF) circulation plays a key role in cerebral waste clearance via the glymphatic system. Although CSF flow velocity is an essential component of CSF dynamics, it has not been sufficiently characterized, and particularly, in studies of the glymphatic system in rat. To investigate the relationship between the flow velocity of CSF in the brain aqueduct and the glymphatic waste clearance rate, using phase-contrast MRI we performed the first measurements of CSF velocity in rats. Phase-contrast MRI was performed using a 7 T system to map mean velocity of CSF flow in the aqueduct in rat brain. The effects of age (3 months old versus 18 months old), gender, strain (Wistar, RNU, Dark Agouti), anesthetic agents (isoflurane versus dexmedetomidine), and neurodegenerative disorder (Alzheimer' disease in Fischer TgF344-AD rats, males and females) on CSF velocity were investigated in eight independent groups of rats (12 rats per group). Our results demonstrated that quantitative velocities of CSF flow in the aqueduct averaged 5.16 ± 0.86 mm/s in healthy young adult male Wistar rats. CSF flow velocity in the aqueduct was not altered by rat gender, strain, and the employed anesthetic agents in all rats, also age in the female rats. However, aged (18 months) Wistar male rats exhibited significantly reduced the CSF flow velocity in the aqueduct (4.31 ± 1.08 mm/s). In addition, Alzheimer's disease further reduced the CSF flow velocity in the aqueduct of male and female rats.

Incremental prognostic utility of congestion markers in cardiac transthyretin amyloidosis.

BACKGROUND/AIMS: Congestion is prognostically relevant in cardiac transthyretin amyloidosis (ATTR-CA), but whether congestion has an incremental prognostic value beyond the well-established, congestion-sensitive NT-proBNP is unknown. Therefore, we aimed to comparatively evaluate the prognostic utility of several congestion surrogates over NT-proBNP. METHODS: We estimated hazard ratios by Cox proportional hazards regressions with time-varying covariates from a panel data set of the local amyloidosis cohort study AmyKoS. Different models were compared by using chi(χ)2-statistics measuring overall model significance. RESULTS/CONCLUSION: 131 ATTR-CA patients (wild-type 84.0%, hereditary 6.9%, without genetic testing 9.2%; median age 78.7 (quartiles 73.3, 82.1) years; 85.5% male) with 566 observations across a median follow-up of 38.2 (30.6; 48.2) months were analyzed. 83.2% received disease-modifying treatment; 20.6% participated concurrently in placebo-controlled gene silencer trials. Information on congestion improved biomarker-driven risk stratification and identified patients at the highest risk. Echocardiographic congestion markers performed better than clinical findings and daily diuretic use/dosage. Relevant adjusters were daily diuretic dosage, disease-modifying treatment, eGFR, and right atrial volume. NT-proBNP and the tricuspid regurgitation peak velocity (tr-vmax) provided an easy-to-use stratification with overall model performance similar to NAC and Mayo staging systems. Further analyses are necessary for validation and to identify the optimal cut points of the congestion markers.

Association between the oxidative balance score and estimated pulse wave velocity from the National Health and Nutrition Examination Survey (2005-2018).

BACKGROUND: No research report has been conducted to investigate the impact of oxidation balance score (OBS) on the estimated pulse wave velocity(ePWV).We aimed to examine the association between OBS and ePWV. METHOD: We evaluated data for 13,073 patients from the National Health and Nutrition Examination Survey (NHANES). The exposure variable was OBS. The outcome variables was combination of ePWV and arterial stiffness. RESULTS: We observed a significant negative correlation between OBS (Per 1SD increase) and ePWV in the gradually adjusted models. Based on the aforementioned results, a two-piecewise logistic regression adjusted model was subsequently employed to establish the association between OBS and elevated ePWV, and the inflection point was determined as 5. The increased risk of elevated ePWV (OR:0.70; 95%CI:0.51-0.94) gradually decreases with the increase of OBS on the left side of the inflection point; however, when OBS exceeds 5, this decrease in risk of elevated ePWV(OR:1.00; 95%CI:0.96-1.04) is no longer observed (P for log likelihood ratio test = 0.028). CONCLUSIONS: There exists a significant association between OBS and ePWV in the context of American adults. Specifically, OBS exhibits a negative correlation with ePWV; however, when considering an elevated ePWV, a saturation effect is observed in relation to OBS.

A prospective observational study to compare and evaluate delta down, aortic velocity time integral variability, and superior vena cava collapsibility index as predictors of fluid responsiveness in patients with supratentorial brain tumors undergoing elective neurosurgery.

Background: Patients undergoing surgical resection of brain tumors frequently exhibit a spectrum of hemodynamic fluctuations necessitating careful fluid management. This study aimed to evaluate the feasibility of dynamic predictors of fluid responsiveness, such as delta down (DD), aortic velocity time integral variability (VTIAoV), and superior vena cava collapsibility index (SVCCI), in patients undergoing neurosurgery for brain tumors. Methods: In this prospective study, 30 patients scheduled to undergo elective neurosurgery for brain tumor resection were enrolled. Baseline measurements of vitals, anesthetic parameters, and study variables were recorded post-induction. Subsequently, patients received a fluid bolus of 10 mL/kg of colloid over 20 min, and measurements were repeated post-loading. Data were presented as mean ± standard deviation. The normally distributed continuous variables were compared using Student's t-test, with P < 0.05 considered statistically significant. The predictive capability of variables for fluid responsiveness was assessed using Pearson's coefficient analysis (r). Results: Of the 30 patients, 22 were identified as volume responders (R), while eight were non-responders (NR). DD >5 mmHg effectively distinguished between R and NR (P < 0.001), with a good predictive ability (r = 0.759). SVCCI >38% differentiated R from NR (P < 0.001), with excellent predictability (r = 0.994). Similarly, VTIAoV >20% was also a good predictor (P < 0.05; r = 0.746). Conclusion: Our study revealed that most patients undergoing surgical resection of brain tumors exhibited fluid responsiveness. Among the variables assessed, SVCCI >38% emerged as an excellent predictor, followed by VTIAoV >20% and DD >5 mm Hg, for evaluating fluid status in this population.

The impacts of muscle-specific force-velocity properties on predictions of mouse muscle function during locomotion.

Introduction: The accuracy of musculoskeletal models and simulations as methods for predicting muscle functional outputs is always improving. However, even the most complex models contain various assumptions and simplifications in how muscle force generation is simulated. One common example is the application of a generalised ("generic") force-velocity relationship, derived from a limited data set to each muscle within a model, uniformly across all muscles irrespective of whether those muscles have "fast" or "slow" contractile properties. Methods: Using a previously built and validated musculoskeletal model and simulation of trotting in the mouse hindlimb, this work examines the predicted functional impact of applying muscle-specific force-velocity properties to typically fast (extensor digitorum longus; EDL) and slow-contracting (soleus; SOL) muscles. Results: Using "real" data led to EDL producing more positive work and acting significantly more spring-like, and soleus producing more negative work and acting more brake-like in function compared to muscles modelled using "generic" force-velocity data. Extrapolating these force-velocity properties to other muscles considered "fast" or "slow" also substantially impacted their predicted function. Importantly, this also further impacted EDL and SOL function beyond that seen when changing only their properties alone, to a point where they show an improved match to ex vivo experimental data. Discussion: These data suggest that further improvements to how musculoskeletal models and simulations predict muscle function should include the use of different values defining their force-velocity relationship depending on their fibre-type composition.

The association between pulse wave velocity and heart failure: a systematic review and meta-analysis.

Background: The arterial stiffness measured by pulsed wave velocity (PWV) is associated with heart failure (HF). However, the effectiveness of arterial stiffness and PWV as prognostic indicators in patients with HFpEF and HFrEF is still unclear. In this systematic review and meta-analysis, we synthesized the prognostic value of PWV and arterial stiffness in HF patients. Methods: Four databases, including Embase, PubMed, Scopus, and Web of Science, were systematically searched for published studies assessing the relationship between PWV and HF from inception up to August 31, 2023. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of the included studies. The standardized mean difference (SMD) and their corresponding 95% confidence intervals (CI) were used to compare PWV in HF (HFrEF and HFpEF) and controls. Meta-regressions based on age, year of publication, sample size, and gender (male percentage) were also conducted. Results: The systematic search yielded 5,977 results, of which 58 met our inclusion criteria and 24 were analyzed quantitatively. Studies included 64,687 patients with a mean age of 53.7 years, and 41,803 (67.3%) were male. Meta-analysis of 19 studies showed that PWV was significantly higher in HF patients compared to the controls (SMD 1.04, 95% CI 0.43-1.66, P < 0.001, I 2 = 93%). Moreover, nine studies have measured PWV among HFrEF and HFpEF patients and found no significant difference (SMD -0.51, 95% CI -1.03 to 0.02, P = 0.057, I2 = 95%). Moreover, increased PWV was linked to an increased chance of developing new-onset HF in individuals with cardiovascular risk factors. Conclusions: Patients with HF exhibit significantly higher arterial stiffness, as indicated by PWV, compared to the normal population. However, this association was not significant between HFrEF and HFpEF patients. Future research is warranted to establish the potential prognostic role of PWV in HF. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023479683, PROSPERO (CRD42023479683).

Association of Anthropometry With Nerve Conduction Parameters of Median Nerve: A Cross-Sectional Study in a North Indian Medical University Hospital.

Background Nerve conduction studies ease the understanding of the various pathologies of the peripheral nervous system. It helps physicians to delineate between the two principal types of peripheral etiologies: axonal degeneration and demyelination. An increase in weight in the form of excessive fat deposition or obesity could have a worrisome effect on nerve conduction. So, to find the association of various anthropometric parameters (age, gender, height, weight, waist-hip ratio and body mass index) with motor and sensory median nerve conduction parameters (latency, amplitude and velocity) this cross-sectional study was conducted. Materials and method A total of 87 subjects were taken and their height, weight, waist-hip ratio and body mass index were measured using standard techniques. Motor and sensory nerve conduction parameters were measured on an electromyography machine. Data was stored, tabulated and analyzed. Results The average height of male and female subjects ± SD was 1.699 ± 0.072 m and 1.589 ± 0.067 m respectively. The average weight of male and female subjects ± SD was 64.089 ± 11.497 kg and 52.949 ± 8.404 kg, respectively. The average BMI of normal, underweight and overweight subjects ± SD was 21.668 ± 2.048 kg/m2, 17.074 ± 0.794 kg/m2 and 26.595 ± 0.915 kg/m2 respectively. Weight showed a significant (p = 0.0025) correlation with the latency of motor median nerve conduction. Waist-hip ratio showed a significant (p = 0.042 and p = 0.036) correlation with motor median nerve conduction velocity in both male and female subjects, respectively. BMI in the overweight category showed a significant (p = 0.0156 and p = 0.0290) correlation with latency and amplitude of motor median nerve conduction study, respectively. Conclusions This study exemplifies that an increase in BMI of our body can affect nerve conduction. This could serve as a preliminary study to assess the effect of obesity on peripheral nerve conduction, especially in the Indian population.

Anaerobic degradation of pesticide wastewater: Improving sludge characteristics and reducing membrane fouling with combined tandem UASB+membrane system with high velocity settlers.

In this pilot study, a combined tandem UASB+membrane reactor (R2) with high velocity settlers was proposed for the treatment of pesticide wastewater at different hydraulic retention times (HRT) and compared with a control reactor (R1). The average COD removal efficiencies of the R2 at HRTs of 96, 72, and 48 h were 83.7 %, 82.8 %, and 74.2 %, which are 14 %, 17 %, and 21 % higher than those of the R1, respectively. Throughout the operation, the biogas production of R2 was 33 %, 19 % and 28 % higher than that of R1 at the same stage, respectively, and the methane yield of R2 (0.19-0.26 L CH4/gCODremoved) was improved by 10-17 % compared to that of R1. Mean α values (VFA/ALK) of 0.13∼0.22 indicated that R2 did not undergo acidification. R2 reduced the extracellular polymers (EPS) content in the attached sludge by 56-62 % compared to R1. It also successfully delayed membrane fouling rate by 19-22 %. The results demonstrate that the R2 has a high treatment capacity, stability, and methane recovery, while also effectively reducing membrane fouling.

Military Injuries: Helocasting Accident.

Background: Accidental injuries sustained during helocasting remain unexamined. Methods: Conditions prevalent during a helocasting exercise performed at a still water body and the resulting casualties were analyzed. Results: Despatch from greater-than-ideal height (>7 m) and speed (>5 knots) causes a high-velocity impact of the body with water in a non-aerodynamic configuration, exposing maximal body area at penetration. The brunt is borne by the torso/back, specifically, the lungs, ribs, and posterior aspect of the spine. The injuries result from direct trauma, sudden deceleration, barotrauma, and hyperflexion. Computerized tomography (CT) is the imaging of choice in the assessment of these injuries. Prompt evacuation to an equipped center, whilst stabilizing the spine in the suspected, proves pivotal to the outcome. Conclusions: Adverse slamming dynamics cause accidental injuries in helocasting. Thorax and spine are predominantly traumatized, both directly and indirectly, and are assessed best using CT. Timely spine stabilization and evacuation prove vital. Accurate assessment of height/speed and adherence to their ideal limits, at despatch, may avert such injuries.

Critical swimming speed at different temperatures for small-bodied freshwater native riverine fish species.

This study evaluated the effect of fish total length (LT) and three water temperatures (10, 15 and 20 °C) on the critical swimming speed (Ucrit) of the species Percilia irwini (2.9-6.3 cm LT), Cheirodon galusdae (3.4-5.5 cm LT), and Trichomycterus areolatus (4.0-6.3 cm LT). An Ucrit estimation model was constructed for each species as a function of temperature and size. The results showed mean Ucrit for P. irwini of 44.56, 53.83 and 63.2 cm s-1 at 10, 15 and 20 °C, respectively: 55.34, 61.74 and 70.05 cm s-1 for C. galusdae and 56.18, 63.01 and 71.09 cm s-1 for T. areolatus. Critical velocity depended on the interaction between species, body length and water. The swimming performance increased significantly with rising temperature in all three species. The velocity also increased with greater fish total length. After controlling for fish total length, velocity also increased with higher temperature in the three species. This research is relevant to small fish species that require conservation measures.

Controlling wind turbine tower vibration under external force by applying control systems combination.

The global focus has recently shifted away from fuel-based power sources, and one of the most important projects for energy production is wind energy. To maintain low costs, the current research examines the problem of vibrations affecting wind turbine towers' performance (WTTs). In particular, the tower, resulting from excessive vibrations, can negatively affect a structure's power output and service life, as it can cause fatigue. Therefore, we conducted numerical tests on various types of controlled systems. Our tests revealed that combining a new technique cubic negative velocity control (CNVC) and linear negative acceleration control (LNAC) was the most effective and cost-efficient option for vibration damping. This solution was derived by using an approximation method for the averaging technique. The external force is an important component of a nonlinear dynamic system and can be characterized by two-degree-of-freedom (2-DOF) differential coupled equations. After implementing the control measures, we conducted a numerical analysis of the vibration values before and after the operation. Stability is studied numerically. The numerical and approximate solutions were confirmed through the frequency response equation and time history with fourth-order Runge-Kutta (RK-4). Finally, we investigated the effect of parameters and compared our results with those of previously published studies.

Association between sleep duration and cardiovascular risk: the EVasCu cross-sectional study.

Introduction: Some cardiovascular risk markers have been associated with alterations in sleep duration in different populations; however, there is little evidence in a healthy population. Aim: The aim of the present study was to analyze the associations between sleep duration and cardiovascular risk biomarkers, including advanced glycation end-products (AGEs) measured by skin autofluorescence (SAF), maximum carotid intima-media thickness (IMTMax), aortic pulse wave velocity (a-PWV), pulse pressure (PP), and low-density lipoprotein cholesterol (LDL-C), in healthy adults (EVasCu study). Methodology: The EVasCu study included 390 participants. Simple and multiple linear regressions were performed between sleep duration and cardiovascular risk markers. ANOVA analysis and ANCOVA analysis adjusted for various covariates were then performed after categorizing sleep into 6 h, 6-8 h, and >8 h. Results: 296 participants were included in the analyses (43.97 ± 12.60 years, 63.9% female). Simple linear regressions showed an inverse association between sleep duration and SAF, IMTMax, aPWV and PP. However, in the multiple linear regression with all the covariates, the statistical significance was lost. For its part, in the ANOVA analyses, sleep duration was also associated with the same parameters, but when performing the fully adjusted ANCOVA analyses, the statistical significance for SAF was maintained (p = 0.015), obtaining a difference of 0.223 arbitrary units (p = 0.017) when comparing the group <6 h vs. > 8 h. Finally, there was no association for LDL-C. Conclusion: An inverse association was found between sleep duration and APS, which is considered a marker of cardiovascular risk. Although prospective studies are needed, it is suggested that insufficient sleep may increase cardiovascular risk, which could be a key factor in future public health policies to promote health and prevent CVD.

Performance Evaluation of Deformable Image Registration Systems - SmartAdapt® and Velocity™.

Aim: To commission and validate commercial deformable image registration (DIR) systems (SmartAdapt® and Velocity™) using task group 132 (TG-132) digital phantom datasets. Additionally, the study compares and verifies the DIR algorithms of the two systems. Materials and Methods: TG-132 digital phantoms were obtained from the American Association of Physicists in Medicine website and imported into SmartAdapt® and Velocity™ systems for commissioning and validation. The registration results were compared with known shifts using rigid registrations and deformable registrations. Virtual head and neck phantoms obtained online (DIR Evaluation Project) and some selected clinical data sets from the department were imported into the two DIR systems. For both of these datasets, DIR was carried out between the source and target images, and the contours were then propagated from the source to the target image data set. The dice similarity coefficient (DSC), mean distance to agreement (MDA), and Jacobian determinant measures were utilised to evaluate the registration results. Results: The recommended criteria for commissioning and validation of DIR system from TG-132 was error <0.5*voxel dimension (vd). Translation only registration: Both systems met TG-132 recommendations except computed tomography (CT)-positron emission tomography registration in both systems (Velocity ~1.1*vd, SmartAdapt ~1.6*vd). Translational and rotational registration: Both systems failed the criteria for all modalities (For velocity, error ranged from 0.6*vd [CT-CT registration] to 3.4*vd [CT-cone-beam CT (CBCT) registration]. For SmartAdapt® the range was 0.6*vd [CT-CBCT] to 3.6*vd [CT-CT]). Mean ± standard deviation for DSC, MDA and Jacobian metrics were used to compare the DIR results between SmartAdapt® and Velocity™. Conclusion: The DIR algorithms of SmartAdapt® and Velocity™ were commissioned and their deformation results were compared. Both systems can be used for clinical purpose. While there were only minimal differences between the two systems, Velocity™ provided lower values for parotids, bladder, rectum, and prostate (soft tissue) compared to SmartAdapt. However, for mandible, spinal cord, and femoral heads (rigid structures), both systems showed nearly identical results.

The Effects of Slow Breathing during Inter-Set Recovery on Power Performance in the Barbell Back Squat.

Slow breathing (SB) reduces sympathetic nervous system activity, the heart rate (HR), and blood pressure (BP) and increases parasympathetic nervous system activity, HR variability, and oxygen saturation which may lead to quicker recovery between bouts of exercise. Therefore, the purpose of this study was to examine whether a SB technique using the 4-7-8 method between sets of barbell back squats (SQs) would attenuate drops in power and bar velocity. In a randomized, crossover design, 18 healthy resistance-trained college-aged males (age: 20.7 ± 1.4 years, body height: 178.6 ± 6.4 cm, body mass: 82.2 ± 15.0 kg, 4.5 ± 2.4 years of experience) performed 5 sets of 3 repetitions of SQs with normal breathing (CON) or SB during the 3-min recovery between sets. Peak and average power and bar velocity were assessed using a linear positioning transducer. HR recovery (RHR), systolic BP recovery (RBP), the rating of perceived exertion (RPE) and the rating of perceived recovery score (RS) were assessed after each set. There were no significant differences between conditions for peak and average power and bar velocity, RBP, RPE, and RS (p > 0.211). SB led to a greater RHR after set 2 (SB: 51.0 ± 14.9 bpm vs. CON: 44.5 ± 11.5 bpm, p = 0.025) and 3 (SB: 48.3 ± 13.5 bpm vs. CON: 37.7 ± 11.7 bpm, p = 0.006) compared to the CON condition. SB was well tolerated, did not hinder nor improve training performance and improved RHR after the middle sets of SQs. Further investigations are warranted to examine the effects of other SB techniques and to determine SB's effects on different training stimuli as well as its effects over an entire workout and post-workout recovery metrics.

Enhancing Training Precision: Unveiling the Barbell Velocity's Role in Tailoring the Resistance Load for the China Badminton Team.

Velocity-based resistance training is a fundamental component of sports science, offering a systematic approach to investigating the load variables of resistance exercises. This research focused on assessing the load across various resistance exercises by examining the barbell velocity during the concentric phase. The study involved 11 male athletes representing the China badminton team, who underwent 1RM testing for bench press, hip thrust, back squat, and single leg press exercises and the maximum repetition testing at load intensities of 60%, 70%, 80%, and 90% of 1RM. Simultaneously, measurements were taken of the barbell's concentric phase velocity during each exercise. The findings revealed a robust negative correlation between barbell velocity and load intensity. Furthermore, exercises engaging greater muscle strength displayed smoother fitting curves. Analysis of velocity loss rates indicated that the hip thrust exhibited a higher completion percentage compared to the back squat and the bench press. Similarly, the non-dominant leg press showed a higher completion percentage than the dominant leg press. The study emphasizes the significance of delineating barbell velocity distributions in resistance training involving large muscle groups, as well as the accurate determination of load intensity. Precise load determination can be facilitated by employing fitting curves derived from distinct movement patterns and varying load intensities. The utilization of velocity data offers a quantifiable approach to achieving targeted training outcomes.

Acute Effects of Slow, Moderate and Fast Tempo Dynamic Stretching Exercises on Power in Well-Trained Male Wrestlers.

Due to the potential detrimental effects of static stretching exercises on subsequent muscle power performance, athletes and trainers have started to replace static stretching with dynamic stretching exercises in their training routines. However, there are no well-accepted guidelines regarding dynamic stretching variables, including tempo/velocity, volume (reps and sets), etc. Therefore, this study aimed to evaluate the acute effects of slow, moderate, and fast tempo dynamic stretching exercises on jump height, relative power, the reactive strength index, and leg stiffness in well-trained male wrestlers. Seventeen wrestlers (aged 20.00 ± 4.06 years, wrestling experience 6.00 ± 3.09 years, and training volume per week 10.00 ± 5.69 hours) took part in the experiment under four conditions (control session, slow tempo dynamic stretching, moderate tempo dynamic stretching, and fast tempo dynamic stretching) on separate days with a 72-h interval in between, following a randomized, crossover study design. The control session consisted of a 10-min jog on a motor-driven treadmill at 6 km/h and a 0% slope. Dynamic stretching sessions consisted of seven dynamic stretching exercises performed at 50 bpm, 100 bpm, and 120 bpm, following a 5-min warm-up on a treadmill at 6 km/h and a 0% slope. After each condition, wrestlers performed a 2 x 30-s repeated vertical jump test with 5-min rest intervals in between. The best results for jump height, relative power, the reactive strength index, and leg stiffness were registered for statistical analysis. One-way repeated ANOVA results demonstrated that there were no significant differences in pairwise comparisons of all variables obtained after the four different conditions (p > 0.05). Overall, none of the slow, moderate, and fast tempo dynamic stretching exercises led to a change in repeated jump performance of well-trained male athletes. Further studies are needed to clarify the acute effects of different tempo dynamic stretching on muscular performance in well-trained wrestlers.

Association between estimated pulse wave velocity and in-hospital and one-year mortality of patients with chronic kidney disease and atherosclerotic heart disease: a retrospective cohort analysis of the MIMIC-IV database.

BACKGROUND: Carotid-femoral pulse wave velocity has been identified as an autonomous predictor of cardiovascular mortality and kidney injury. This important clinical parameter can be non-invasively estimated using the calculated pulse wave velocity (ePWV). The objective of this study was to examine the correlation between ePWV and in-hospital as well as one-year mortality among critically ill patients with chronic kidney disease (CKD) and atherosclerotic heart disease (ASHD). METHODS: This study included a cohort of 1173 patients diagnosed with both CKD and ASHD, sourced from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The four groups divided into quartiles according to ePWV were compared using a Kaplan-Meier survival curve to assess variations in survival rates. Cox proportional hazards models were employed to analyze the correlation between ePWV and in-hospital as well as one-year mortality among critically ill patients with both CKD and ASHD. To further investigate the dose-response relationship, a restricted cubic splines (RCS) model was utilized. Additionally, stratification analyses were performed to examine the impact of ePWV on hospital and one-year mortality across different subgroups. RESULTS: The survival analysis results revealed a negative correlation between higher ePWV and survival rate. After adjusting for confounding factors, higher ePWV level (ePWV > 11.90 m/s) exhibited a statistically significant association with an increased risk of both in-hospital and one-year mortality among patients diagnosed with both CKD and ASHD (HR = 4.72, 95% CI = 3.01-7.39, p < 0.001; HR = 2.04, 95% CI = 1.31-3.19, p = 0.002). The analysis incorporating an RCS model confirmed a linear escalation in the risk of both in-hospital and one-year mortality with rising ePWV values (P for nonlinearity = 0.619; P for nonlinearity = 0.267). CONCLUSIONS: The ePWV may be a potential marker for the in-hospital and one-year mortality assessment of CKD with ASHD, and elevated ePWV was strongly correlated with an elevated mortality risk in patients diagnosed with both CKD and ASHD.