Early regression index (ERI) on MR images as response predictor in esophageal cancer treated with neoadjuvant chemo-radiotherapy: Interim analysis of the prospective ESCAPE trial.

PURPOSE: The early regression index (ERI) predicts treatment response in rectal cancer patients. Aim of current study was to prospectively assess tumor response to neoadjuvant chemo-radiotherapy (nCRT) of locally advanced esophageal cancer using ERI, based on MRI. MATERIAL AND METHODS: From January 2020 to May 2023, 30 patients with esophageal cancer were enrolled in a prospective study (ESCAPE). PET-MRI was performed: i) before nCRT (tpre); ii) at mid-radiotherapy, tmid; iii) after nCRT, 2-6 weeks before surgery (tpost); nCRT delivered 41.4 Gy/23fr with concurrent carboplatin and paclitaxel. For patients that skipped surgery, complete clinical response (cCR) was assessed if patients showed no local relapse after 18 months; patients with pathological complete response (pCR) or with cCR were considered as complete responders (pCR + cCR). GTV volumes were delineated by two observers (Vpre, Vmid, Vpost) on T2w MRI: ERI and other volume regression parameters at tmid and tpost were tested as predictors of pCR + cCR. RESULTS: Complete data of 25 patients were available at the time of the analysis: 3/25 with complete response at imaging refused surgery and 2/3 were cCR; in total, 10/25 patients showed pCR + cCR (pCR = 8/22). Both ERImid and ERIpost classified pCR + cCR patients, with ERImid showing better performance (AUC:0.78, p = 0.014): A two-variable logistic model combining ERImid and Vpre improved performances (AUC:0.93, p < 0.0001). Inter-observer variability in contouring GTV did not affect the results. CONCLUSIONS: Despite the limited numbers, interim analysis of ESCAPE study suggests ERI as a potential predictor of complete response after nCRT for esophageal cancer. Further validation on larger populations is warranted.

Extended nodal radiotherapy for prostate cancer relapse guided with [11C]-choline PET/CT: ten-year results in patients enrolled in a prospective trial.

AIMS: To report long-term outcomes of relapsed prostate cancer (PC) patients treated in a prospective single-arm study with extended-nodal radiotherapy (ENRT) and [11C]-choline positron emission tomography (PET)/computed tomography (CT)-guided simultaneous integrated boost (SIB) to positive lymph nodes (LNs). METHODS: From 12/2009 to 04/2015, 60 PC patients with biochemical relapse and positive LNs only were treated in this study. ENRT at a median total dose (TD) = 51.8 Gy/28 fr and PET/CT-guided SIB to positive LNs at a median TD = 65.5 Gy was prescribed. Median PSA at relapse was 2.3 (interquartile range, IQR:1.3-4.0) ng/ml. Median number of positive LNs: 2 (range: 1-18). Androgen deprivation therapy (ADT) was prescribed for 48 patients for a median of 30.7 (IQR: 18.5-43.1) months. RESULTS: Median follow-up from the end of salvage treatment was 121.8 (IQR: 116.1, 130.9) months; 3-, 5-, and 10-year BRFS were 45.0%, 36.0%, and 24.0%, respectively; DMFS: 67.9%, 57.2%, and 45.2%; CRFS: 62.9%, 53.9%, and 42.0%; and OS: 88.2%, 76.3%, and 47.9%, respectively. Castration resistance (p < 0.0001) and ≥ 6 positive LN (p = 0.0024) significantly influenced OS at multivariate analysis. Castration resistance (p < 0.0001 for both) influenced DMFS and CRFS in multivariate analysis. CONCLUSIONS: In PC relapsed patients treated with ENRT and [11C]-choline-PET/CT-guided SIB for positive LNs, with 10-year follow-up, a median Kaplan-Meier estimate CRFS of 67 months and OS of 110 months were obtained. These highly favorable results should be confirmed in a prospective, randomized trial.

Sensorimotor integration is affected by acute whole-body vibration: a coherence study.

Introduction: Several whole-body vibration (WBV) effects on performance have been related to potential changes in the neural drive, motor unit firing rate, and sensorimotor integration. In the present paper, motor unit coherence analysis was performed to detect the source of neural modulation based on the frequency domain. Methods: Thirteen men [25 ± 2.1 years; Body Mass Index (BMI) = 23.9 ± 1.3 kg m2; maximal voluntary force (MVF): 324.36 ± 41.26 N] performed sustained contractions of the Tibialis Anterior (TA) at 10%MVF before and after acute WBV. The vibrating stimulus was applied barefoot through a platform to target the TA. High-Density surface Electromyography (HDsEMG) was used to record the myoelectrical activity of TA to evaluate coherence from motor unit cumulative spike-trains (CSTs). Results: Mean coherence showed a significant decrease in the alpha and low-beta bandwidths (alpha: from 0.143 ± 0.129 to 0.132 ± 0.129, p = 0.035; low-beta: from 0.117 ± 0.039 to 0.086 ± 0.03, p = 0.0001), whereas no significant changes were found in the other ones (p > 0.05). The discharge rate (DR) and the Force Covariance (CovF%) were not significantly affected by acute WBV exposure (p > 0.05). Discussion: According to the significant effects found in alpha and low-beta bandwidths, which reflect sensorimotor integration parameters, accompanied by no differences in the DR and CovF%, the present results underlined that possible neural mechanisms at the base of the previously reported performance enhancements following acute WBV are likely based on sensorimotor integration rather than direct neural drive modulation.

The acute effects of whole-body vibration on motor unit recruitment and discharge properties.

Introduction: several studies have reported improved neuromuscular parameters in response to whole-body vibration (WBV). This is likely achieved by modulation of the central nervous system (CNS). Reduced recruitment threshold (RT), which is the % of Maximal Voluntary Force (%MVF) at which a given Motor Unit (MU) is recruited, may be responsible for the force/power improvements observed in several studies. Methods: 14 men (25 ± 2.3 years; BMI = 23.3 ± 1.5 kg m2 MVF: 319.82 ± 45.74 N) performed trapezoidal isometric contractions of the tibialis anterior (TA) at 35-50-70 %MVF before and after three conditions: WBV, STAND (standing posture), and CNT (no intervention). The vibration was applied through a platform for targeting the TA. High-density surface electromyography (HDsEMG) recordings and analysis were used to detect changes in the RT and Discharge Rate (DR) of the MUs. Results: Mean motor unit recruitment threshold (MURT) reached 32.04 ± 3.28 %MVF before and 31.2 ± 3.72 %MVF after WBV, with no significant differences between conditions (p > 0.05). Additionally, no significant changes were found in the mean motor unit discharge rate (before WBV: 21.11 ± 2.94 pps; after WBV: 21.19 ± 2.17 pps). Discussion: The present study showed no significant changes in motor unit properties at the base of neuromuscular changes documented in previous studies. Further investigations are needed to understand motor unit responses to different vibration protocols and the chronic effect of vibration exposure on motor control strategies.

Sensors and actuators for the advanced LIGO A+ upgrade.

Advanced Laser Interferometer Gravitational-wave Observatory (LIGO A+) is a major upgrade to LIGO-the Laser Interferometer Gravitational-wave Observatory. For the A+ project, we have developed, produced, and characterized sensors and electronics to interrogate new optical suspensions designed to isolate optics from vibrations. The central element is a displacement sensor with an integrated electromagnetic actuator known as a BOSEM (Birmingham Optical Sensor and ElectroMagnetic actuator) and its readout and drive electronics required to integrate them into LIGO's control and data system. In this paper, we report on the improvements to the sensors and the testing procedures undertaken to meet the enhanced performance requirements set out by the A+ upgrade to the detectors. The best devices reach a noise level of 4.5 ×10-11m/Hz at a measurement frequency of 1 Hz, an improvement of 6.7 times over standard devices.

ASSESSMENT OF PCXMC MONTE CARLO SIMULATIONS IN SLOT-SCANNING-BASED EXAMINATIONS: COMPARISON WITH IN-PHANTOM THERMOLUMINESCENT DOSIMETRY.

Slot-scanning technology is nowadays a valid solution for the follow-up of chronic musculoskeletal disorders on children and adolescent patients, but there is no commercial software designed for simulating this X-ray beam geometry. PC Program for X-ray Monte Carlo (PCXMC) is a widespread Monte Carlo software developed for dose computation in projection radiography. In this study, experimental measurements were performed to evaluate its applicability in examinations with a slit-beam device. Physical phantoms corresponding to an adult and a 5-y-old child with calibrated thermoluminescent dosemeters were used for experiments. Different simulation approaches were investigated. Differences between measured and calculated organ doses ranged from -95 to 67% and were statistically significant for almost all organs. For both patients, PCXMC underestimated the effective dose of about 25%. This study suggests that PCXMC is not suited for organ dose evaluation in examinations with slot-scanning devices. It is still a useful tool for effective dose estimation when a proper correction factor is applied.

Rotavirus immunisation status affects the efficacy of Lacticaseibacillus rhamnosus GG for the treatment of children with acute diarrhoea: a meta-analysis.

The efficacy of Lacticaseibacillus rhamonosus GG (LGG) for the treatment of children with acute gastroenteritis has been debated based on most recent evidence. Previous evidence demonstrated that LGG mainly benefits children with Rotavirus infection compared to other aetiologies. However, Rotavirus immunisation (RVI) has been implemented worldwide since 2006. We aimed to investigate whether the efficacy of LGG in children with gastroenteritis vary according to RVI status. The MEDLINE, Embase and Cochrane library databases were searched for relevant randomised controlled trials (RCT) up to April 2022. The duration of diarrhoea and episodes lasting >48 h were considered as primary outcomes. The date of vaccine introduction and RVI coverage were reviewed for all countries where trials were conducted. Among the 15 RCTs included in the analysis (n=3,465), only 5 showed a low risk of bias. In RCT conducted before the introduction of RVI (n=2,932), LGG was effective in reducing the duration of diarrhoea compared with placebo or standard care (Median -23.80 h, 95% confidence interval (CI) -36.59 to -11.02]). Only 2 RCTs (n=1,072) reported data of populations partially immunised against Rotavirus with an overall coverage of 44 and 67%, respectively. In this population, LGG showed no efficacy in reducing the duration of diarrhoea (Median -5.34, 95%CI -12.9 to 2.22). Similarly, LGG reduced the risk of diarrhoea lasting >48 h in children not immunised against Rotavirus (RR 0.73, 95%CI 0.54-0.99), but not in population partially immunised (RR 0.98, 95%CI 0.87 to 1.11). The implementation of RVI might affect the efficacy of LGG modifying local epidemiology and susceptibility of the target population to selected probiotics.

Reduction in broad-spectrum antimicrobial prescriptions by primary care pediatricians following a multifaceted antimicrobial stewardship program.

Background: Since 2016, following the Italian "National Plan to Contrast Antimicrobial Resistance", Campania Region has implemented an antimicrobial stewardship program, including the obligation to associate an appropriate International Classification of Diseases-9 code to each antibiotic prescription, the publication of schemes for empirical antibiotic therapy and educational interventions. Methods: To evaluate the impact of these interventions on the prescribing habits of family pediatricians, we conducted a retrospective cohort study (January 2016-December 2020), including all patients registered in an associate practice of Primary Care Pediatricians. We collected data on antibiotic prescriptions through a specific study management software; our primary outcomes were the annual prescription rates, calculated for both the number of patients in follow-up and the number of medical consultations, and the annual prescription rates for selected antibiotic classes and molecules. To investigate the hypothesis that chronic conditions would be associated with an increased rate of prescription, we also tested the association between underlying conditions and the number of antibiotics received. Results: During the study period, 2,599 children received 11,364 antibiotic prescriptions (mean 4.37, SD 4.28). From 2016 to 2020 we observed a substantial reduction in both the annual prescription rate per 100 patients (9.33 to 3.39; R 2 = 0.927, p = 0.009), and the annual prescription rate per 100 medical consultations (25.49 to 15.98; R 2 = 0.996, p < 0.01). The prescription rates of Amoxicillin-Clavulanate (50.25 to 14.21; R 2 = 0.983, p = 0.001) and third generation Cephalosporins (28.43 to 5.43; R 2 = 0.995, p < 0.01) significantly decreased; we didn't find significant modifications in the prescription rates of Amoxicillin and Quinolones; finally, we observed a trend toward reduction in the prescription of Macrolides. No statistical association was found between antibiotics prescribing frequency and history of chronic diseases. Discussion: Following the implementation of the regional interventions on antimicrobial stewardship, we observed a substantial reduction in the overall antibiotic prescription per patients and per medical consultations, with a statistically significant reduction in the use of broad-spectrum molecules. Considering the results of our analysis, new guidance and training interventions addressed to specialists in the primary care sector should be implemented to further limit antibiotic resistance.

Effects of laser photobiomodulation in the management of oral lichen planus: a literature review.

Objectives: This review aims to understand whether Photobio-modulation (PBM) therapy is a valid aid in the management of Oral Lichen Planus (OLP) and its symptoms. Moreover, an analysis to determine whether it is a valid replacement for conventional therapies and whether standardized protocols can be used in PBM sessions or whether these should be changed depending on the type of injury has been made. Finally, an evaluation to determine whether PBM may induce transformation of dysplastic oral keratinocytes into squamous cell carcinoma has been made. Materials and Methods: Searches were conducted on two search databases for relevant publications released between 1992 and 2019. The databases used were: Pubmed "Medline", and Google Scholar. Forty-four articles complied with the inclusion criteria and were included for quality assessment and data extraction. Results: All the studies reported positive effects of PBM; how-ever, there was wide heterogeneity in the laser parameters used in the management of the OLP. The effective dose ranges from 2 to 3 J/cm2, in order to see the desired biological effects. Conclusions: PBM is useful in controlling algal sensation and can be used in cases of OLP lesions that are not responsive to conventional therapies or when corticosteroid doses are too high for the patient, resulting in possible side effects. Standardized biostimulation protocols with further scientific insights are therefore required.

Only the Fastest Corticospinal Fibers Contribute to ß Corticomuscular Coherence.

Human corticospinal transmission is commonly studied using brain stimulation. However, this approach is biased to activity in the fastest conducting axons. It is unclear whether conclusions obtained in this context are representative of volitional activity in mild-to-moderate contractions. An alternative to overcome this limitation may be to study the corticospinal transmission of endogenously generated brain activity. Here, we investigate in humans (N = 19; of either sex), the transmission speeds of cortical ß rhythms (∼20 Hz) traveling to arm (first dorsal interosseous) and leg (tibialis anterior; TA) muscles during tonic mild contractions. For this purpose, we propose two improvements for the estimation of corticomuscular ß transmission delays. First, we show that the cumulant density (cross-covariance) is more accurate than the commonly-used directed coherence to estimate transmission delays in bidirectional systems transmitting band-limited signals. Second, we show that when spiking motor unit activity is used instead of interference electromyography, corticomuscular transmission delay estimates are unaffected by the shapes of the motor unit action potentials (MUAPs). Applying these improvements, we show that descending corticomuscular ß transmission is only 1-2 ms slower than expected from the fastest corticospinal pathways. In the last part of our work, we show results from simulations using estimated distributions of the conduction velocities for descending axons projecting to lower motoneurons (from macaque histologic measurements) to suggest two scenarios that can explain fast corticomuscular transmission: either only the fastest corticospinal axons selectively transmit ß activity, or else the entire pool does. The implications of these two scenarios for our understanding of corticomuscular interactions are discussed.SIGNIFICANCE STATEMENT We present and validate an improved methodology to measure the delay in the transmission of cortical ß activity to tonically-active muscles. The estimated corticomuscular ß transmission delays obtained with this approach are remarkably similar to those expected from transmission in the fastest corticospinal axons. A simulation of ß transmission along a pool of corticospinal axons using an estimated distribution of fiber diameters suggests two possible mechanisms by which fast corticomuscular transmission is achieved: either a very small fraction of the fastest descending axons transmits ß activity to the muscles or, alternatively, the entire population does and natural cancellation of slow channels occurs because of the distribution of axon diameters in the corticospinal tract.

Spinal motoneurons of the human newborn are highly synchronized during leg movements.

Motoneurons of neonatal rodents show synchronous activity that modulates the development of the neuromuscular system. However, the characteristics of the activity of human neonatal motoneurons are largely unknown. Using a noninvasive neural interface, we identified the discharge timings of individual spinal motoneurons in human newborns. We found highly synchronized activities of motoneurons of the tibialis anterior muscle, which were associated with fast leg movements. Although neonates' motor units exhibited discharge rates similar to those of adults, their synchronization was significantly greater than in adults. Moreover, neonatal motor units showed coherent oscillations in the delta band, which is directly translated into force generation. These results suggest that motoneuron synchronization in human neonates might be an important mechanism for controlling fast limb movements, such as those of primitive reflexes. In addition to help revealing mechanisms of development, the proposed neural interface might monitor children at risk of developing motor disorders.

BriXS, a new X-ray inverse Compton source for medical applications.

MariX is a research infrastructure conceived for multi-disciplinary studies, based on a cutting-edge system of combined electron accelerators at the forefront of the world-wide scenario of X-ray sources. The generation of X-rays over a large photon energy range will be enabled by two unique X-ray sources: a Free Electron Laser and an inverse Compton source, called BriXS (Bright compact X-ray Source). The X-ray beam provided by BriXS is expected to have an average energy tunable in the range 20-180 keV and intensities between 1011 and 1013 photon/s within a relative bandwidth ΔE/E=1-10%. These characteristics, together with a very small source size (~20 µm) and a good transverse coherence, will enable a wide range of applications in the bio-medical field. An additional unique feature of BriXS will be the possibility to make a quick switch of the X-ray energy between two values for dual-energy and K-edge subtraction imaging. In this paper, the expected characteristics of BriXS will be presented, with a particular focus on the features of interest to its possible medical applications.

Tutorial: Analysis of motor unit discharge characteristics from high-density surface EMG signals.

Recent work demonstrated that it is possible to identify motor unit discharge times from high-density surface EMG (HDEMG) decomposition. Since then, the number of studies that use HDEMG decomposition for motor unit investigations has increased considerably. Although HDEMG decomposition is a semi-automatic process, the analysis and interpretation of the motor unit pulse trains requires a thorough inspection of the output of the decomposition result. Here, we report guidelines to perform an accurate extraction of motor unit discharge times and interpretation of the signals. This tutorial includes a discussion of the differences between the extraction of global EMG signal features versus the identification of motor unit activity for physiological investigations followed by a comprehensive guide on how to acquire, inspect, and decompose HDEMG signals, and robust extraction of motor unit discharge characteristics.

CO2 laser ablation of oral leukoplakia: with or without extension of margins?

PURPOSE: The purpose is to determine the sufficient extension of margins during laser ablation of oral leukoplakia and observe its short-term recurrence rate. MATERIALS AND METHODS: The study was designed as a randomized controlled clinical trial was conducted on 33 oral leukoplakia lesions diagnosed in 30 patients (16 Females and 14 Males) with an age range between 39 and 79 years. The lesions were divided into three groups; Group A: 11 lesions in 11 patients, in which the laser ablation was done for the entire lesion without extension of margins; Group B: 11 lesions in 8 patients, in which the laser ablation was done for the lesion adding at least 3mm extension of margins; and finally the Group Control: consists of 11 untreated lesions in 11 patients, in which only "wait and see" approach was done. RESULTS: Complete healing of 13 lesions occurred in both groups A and B. Complete regression of 3 lesions occurred in Group Control. After 6 months of follow-up, 6 of 9 lesions in both groups A and B that showed the recurrence, had shown an initial recurrence after 3 weeks of the laser ablation. Patients with no history of smoking habits showed complete healing of 87.5%, while in ex-smokers complete healing was 42.8%. The statistical analysis was performed, and the averages of all groups are significantly different (p <0.00001). DISCUSSION: The primary treatment focuses on the elimination of associated risk factors (smoking, alcohol, and local irritating factors). In the literature, the recurrence rate varies between 13.6% and 40.7%, while in our study, it was 45.5% in Group A and 36.4% in Group B. CONCLUSION: The recommended extension of margins should be at least 3mm in width. Further research can be performed to evaluate the immediate re-ablation of the lesions which showed an initial recurrence after 3 weeks of laser ablation.

The human central nervous system transmits common synaptic inputs to distinct motor neuron pools during non-synergistic digit actions.

KEY POINTS: Neural connectivity between distinct motor neuronal modules in the spinal cord is classically studied through electrical stimulation or multi-muscle EMG recordings. We quantified the strength of correlation in the activity of two distinct populations of motor neurons innervating the thenar and first dorsal interosseous muscles during tasks that required the two hand muscles to exert matched or un-matched forces in different directions. We show that when the two hand muscles are concurrently activated, synaptic input to the two motor neuron pools is shared across all frequency bandwidths (representing cortical and spinal input) associated with force control. The observed connectivity indicates that motor neuron pools receive common input even when digit actions do not belong to a common behavioural repertoire. ABSTRACT: Neural connectivity between distinct motor neuronal modules in the spinal cord is classically studied through electrical stimulation or multi-muscle EMG recordings. Here we quantify the strength of correlation in the activity of two distinct populations of motor neurons innervating the thenar and first dorsal interosseous muscles in humans during voluntary contractions. To remove confounds associated with previous studies, we used a task that required the two hand muscles to exert matched or un-matched forces in different directions. Despite the force production task consisting of uncommon digit force coordination patterns, we found that synaptic input to motor neurons is shared across all frequency bands, reflecting cortical and spinal inputs associated with force control. The coherence between discharge timings of the two pools of motor neurons was significant at the delta (0-5 Hz), alpha (5-15 Hz) and beta (15-35 Hz) bands (P < 0.05). These results suggest that correlated input to motor neurons of two hand muscles can occur even during tasks not belonging to a common behavioural repertoire and despite lack of common innervation. Moreover, we show that the extraction of activity from motor neurons during voluntary force control removes cross-talk associated with global EMG recordings, thus allowing direct in vivo interrogation of spinal motor neuron activity.

Interfacing the neural output of the spinal cord: robust and reliable longitudinal identification of motor neurons in humans.

OBJECTIVE: Non-invasive electromyographic techniques can detect action potentials from muscle units with high spatial dimensionality. These technologies allow the decoding of large samples of motor units by using high-density grids of electrodes that are placed on the skin overlying contracting muscles and therefore provide a non-invasive representation of the human spinal cord output. APPROACH: From a sample of >1200 decoded motor neurons, we show that motor neuron activity can be identified in humans in the full muscle recruitment range with high accuracy. MAIN RESULTS: After showing the validity of decomposition with novel test parameters, we demonstrate that the same motor neurons can be tracked over a period of one-month, which allows for the longitudinal analysis of individual human neural cells. SIGNIFICANCE: These results show the potential of an accurate and reliable assessment of large populations of motor neurons in physiological investigations. We discuss the potential of this non-invasive neural interfacing technology for the study of the neural determinants of movement and man-machine interfacing.

Higher muscle fiber conduction velocity and early rate of torque development in chronically strength-trained individuals.

Strength-trained individuals (ST) develop greater levels of force compared with untrained subjects. These differences are partly of neural origin and can be explained by training-induced changes in the neural drive to the muscles. In the present study we hypothesize a greater rate of torque development (RTD) and faster recruitment of motor units with greater muscle fiber conduction velocity (MFCV) in ST compared with a control cohort. MFCV was assessed during maximal voluntary isometric explosive contractions of the elbow flexors in eight ST and eight control individuals. MFCV was estimated from high-density surface electromyogram recordings (128 electrodes) in intervals of 50 ms starting from the onset of the electromyogram. RTD and MFCV were computed and normalized to their maximal voluntary torque (MVT) values. The explosive torque of the ST was greater than in the control group in all time intervals analyzed (P < 0.001). The absolute MFCV values were also greater for the ST than for controls at all time intervals (P < 0.001). ST also achieved greater normalized RTD in the first 50 ms of contraction [887.6 (152) vs. 568.5 (148.66)%MVT/s, mean (SD), P < 0.001] and normalized MFCV before the rise in force compared with controls. We have shown for the first time that ST can recruit motor units with greater MFCV in a shorter amount of time compared with untrained subjects during maximal voluntary isometric explosive contractions.NEW & NOTEWORTHY Strength-trained individuals show neuromuscular adaptations. These adaptations have been partly related to changes in the neural drive to the muscles. Here, we show for the first time that during the initial phase of a maximal isometric explosive contraction, strength-trained individuals achieve higher levels of force and recruit motor units with greater conduction velocities.

Central nervous system modulates the neuromechanical delay in a broad range for the control of muscle force.

Force is generated by muscle units according to the neural activation sent by motor neurons. The motor unit is therefore the interface between the neural coding of movement and the musculotendinous system. Here we propose a method to accurately measure the latency between an estimate of the neural drive to muscle and force. Furthermore, we systematically investigate this latency, which we refer to as the neuromechanical delay (NMD), as a function of the rate of force generation. In two experimental sessions, eight men performed isometric finger abduction and ankle dorsiflexion sinusoidal contractions at three frequencies and peak-to-peak amplitudes {0.5, 1, and 1.5 Hz; 1, 5, and 10 of maximal force [%maximal voluntary contraction (MVC)]}, with a mean force of 10% MVC. The discharge timings of motor units of the first dorsal interosseous (FDI) and tibialis anterior (TA) muscle were identified by high-density surface EMG decomposition. The neural drive was estimated as the cumulative discharge timings of the identified motor units. The neural drive predicted 80 ± 0.4% of the force fluctuations and consistently anticipated force by 194.6 ± 55 ms (average across conditions and muscles). The NMD decreased nonlinearly with the rate of force generation ( R2 = 0.82 ± 0.07; exponential fitting) with a broad range of values (from 70 to 385 ms) and was 66 ± 0.01 ms shorter for the FDI than TA ( P < 0.001). In conclusion, we provided a method to estimate the delay between the neural control and force generation, and we showed that this delay is muscle-dependent and is modulated within a wide range by the central nervous system. NEW & NOTEWORTHY The motor unit is a neuromechanical interface that converts neural signals into mechanical force with a delay determined by neural and peripheral properties. Classically, this delay has been assessed from the muscle resting level or during electrically elicited contractions. In the present study, we introduce the neuromechanical delay as the latency between the neural drive to muscle and force during variable-force contractions, and we show that it is broadly modulated by the central nervous system.

Beef meat preferences of consumers from Northwest Italy: Analysis of choice attributes.

In this research the importance of several choice attributes of beef for Piedmontese consumers was examined. The survey was conducted on a sample of consumers in sixteen meat stores in Piedmont, Northwest Italy. A choice experiment (Best-Worst scaling methodology) was used to identify consumer preferences and five clusters of purchaser. The responses were also analyzed on the basis of two variables, the frequency of meat consumption and the place of purchase. Piedmontese consumers considered "price" as the most important factor in meat purchasing, but "animal welfare" considerations played some part too.