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In this review, a pedagogical introduction to the concepts of slow-roll inflationary universe and number of e-folds is provided. In particular, the differences between the basic notion of number of e-folds ( N e ), total number of e-folds ( N T ) and number of e-folds before the end of inflation (N) are outlined. The proper application of the number of e-folds before the end of inflation is discussed both as a time-like variable for the scalar field evolution and as a key parameter for computing inflationary predictions. [ABSTRACT FROM AUTHOR]

We study a class of early universe cosmological models based on Einstein–Cartan gravity and including a higher derivative term corresponding to a power of the Holst scalar curvature. The resulting effective action is basically given by General Relativity and an additional neutral pseudoscalar field (the pseudoscalaron), unequivocally related to the corresponding components of the torsion, that necessarily acquire a dynamics. The induced pseudoscalaron potential provides a realistic inflationary phase together with a very rich postinflationary epoch, resulting from the coupling of the pseudoscalaron to ordinary matter. [ABSTRACT FROM AUTHOR]

Theories of grounded cognition assume that conceptual representations are grounded in sensorimotor experience. However, abstract concepts such as jealousy or childhood have no directly associated referents with which such sensorimotor experience can be made; therefore, the grounding of abstract concepts has long been a topic of debate. Here, we propose (a) that systematic relations exist between semantic representations learned from language on the one hand and perceptual experience on the other hand, (b) that these relations can be learned in a bottom-up fashion, and (c) that it is possible to extrapolate from this learning experience to predict expected perceptual representations for words even where direct experience is missing. To test this, we implement a data-driven computational model that is trained to map language-based representations (obtained from text corpora, representing language experience) onto vision-based representations (obtained from an image database, representing perceptual experience), and apply its mapping function onto language-based representations for abstract and concrete words outside the training set. In three experiments, we present participants with these words, accompanied by two images: the image predicted by the model and a random control image. Results show that participants' judgements were in line with model predictions even for the most abstract words. This preference was stronger for more concrete items and decreased for the more abstract ones. Taken together, our findings have substantial implications in support of the grounding of abstract words, suggesting that we can tap into our previous experience to create possible visual representation we don't have. [ABSTRACT FROM AUTHOR]

This review summarizes body circumference-based anthropometrics that are in common use for research and in some cases clinical application. These include waist and hip circumference-based central body indices to predict cardiometabolic risk: waist circumference, waist-to-hip ratio, waist-to-height ratio, waist-to-thigh ratio, body adiposity index, a body shape index (ABSI), hip index (HI), and body roundness index (BRI). Limb circumference measurements are most often used to assess sarcopenia and include: thigh circumference, calf circumference, and mid-arm circumference. Additionally, this review presents fascinating recent developments in optic-based imaging technologies that have elucidated changes over the last decades in average body size and shape in European populations. The classical apple and pear shape concepts of body shape difference remain useful, but novel and exciting 3-D optical "e-taper" measurements provide a potentially powerful new future vista in anthropometrics. [ABSTRACT FROM AUTHOR]

We explore the consequences of a time-dependent inflaton equation-of-state (EoS) parameter in the context of the post-inflationary perturbative Boltzmann reheating. In particular, we numerically solve the perturbative coupled system of Boltzmann equations involving the inflaton energy density, the radiation energy density and the related entropy density and temperature of the produced particle thermal bath. We exploit reasonable Ansätze for the EoS and discuss the robustness of the Boltzmann system. We also comment on the possible microscopic origin related to a time-dependent inflaton potential, discussing the consequences on a preheating stage and the related (primordial) gravitational waves. [ABSTRACT FROM AUTHOR]

The generalized skeletal muscle disorder that involves (in elderly subjects) the progressive loss of muscle mass and function has been defined sarcopenia, whereas the rapid-onset (traumatic or surgical) and focal (unilateral) loss of skeletal muscle with resultant functional impairment has been defined volumetric muscle loss. Different tools and approaches are commonly used in the clinical settings to quantify the loss of muscle or lean mass and to assess the consequent motor impairment. This review describes the technical principles and provides a summary of the main parameters that can be obtained to assess lean mass (and its distribution) or muscle size (and its structure) through the two imaging techniques most easily accessible and therefore frequently adopted in the clinical practice: dual-energy X-ray absorptiometry and muscle ultrasonography. [ABSTRACT FROM AUTHOR]

Normative measures of verbal material are fundamental in psycholinguistic and cognitive research for the control of confounding in experimental procedures and for achieving a better comprehension of our conceptual system. Traditionally, normative studies have focused on classical psycholinguistic variables, such as concreteness and imageability. Recent works have shifted researchers' focus to perceptual strength, in which items are rated separately for each of the five senses. We present a resource that includes perceptual norms for 1,121 Italian words extracted from the Italian version of ANEW. Norms were collected from 57 native speakers. For each word, the participants provided perceptual-strength ratings for each of the five perceptual modalities. The perceptual norms performance in predicting human behavior was tested in two novel experiments, a lexical decision task and a naming task. Concreteness, imageability, and different composite variables representing perceptual-strength scores were considered as competing predictors in a series of linear regressions, evaluating the goodness of fit of each model. For both tasks, the model with imageability as the only predictor was found to be the best-fitting model according to the Akaike information criterion, whereas the model with the separately considered five modalities better described data according to the explained variance. These results differ from the ones previously reported for English, in which maximum perceptual strength emerged as the best predictor of behavior. We investigated this discrepancy by comparing Italian and English data for the same set of translated items, thus confirming a genuine cross-linguistic effect. We thus confirmed that perceptual experience influences linguistic processing, even though evaluations from different languages are needed to generalize this claim. [ABSTRACT FROM AUTHOR]

The wall pressure fluctuations induced by a subsonic circular jet on a rigid flat plate have been investigated considering two jets with different exit section diameters at the same Mach number. The analysis is aimed at completing the series of papers presented by the authors on the interaction between a subsonic jet and infinite tangential flat plate where the exit Mach number was the only parameter of the jet flow that was varied. In order to analyse other effects out of the Mach number, two configurations with different nozzle exhaust diameters were explored with the objective of isolating the Reynolds number effect keeping fixed the exit Mach number. The nozzle exhaust diameters are 12 mm and 25.4 mm and the instrumented flat plate, installed parallel to the jet flow, is moved at different radial distances from the jet axis. The pressure footprint on the plate has been measured in the stream-wise direction by means of a pair of flush-mounted pressure transducers, providing point-wise pressure signals. Wall pressure fluctuations have been characterised in terms of spectral and statistical quantities. The effect of Reynolds is evidenced and possible scaling relationships that account for the Reynolds dependence are proposed. Implications for modeling the spectral coherence have been considered by the application of the Corcos' model and the effect of the jet Reynolds number on the model coefficients is analyzed. [ABSTRACT FROM AUTHOR]

Despite a large body of evidence suggests positive effects of playing action video games and practising sports on various visual attentional skills, the impact of these activities on the ability to maintain attention over prolonged periods of time (i.e., sustained attention) has been largely neglected. Here, we first explored free-time habits on a group of 310 adolescents by means of a self-reported questionnaire. We found an inverse relationship between the time spent with sports and video games, but not with other extra-scholastic activities: the time spent practising sports and playing video games clearly competed with each other, with the more-intensive-sport practitioners being less involved in video game play. Next, we directly measured sustained attention and other attentional skills in a subgroup of 76 participants, divided as a function of their time spent in sports and action video games. In particular, sustained attention was assessed by means of two tasks: a classic exogenous task, requiring participants to attend to a flashing visual stimulus; and an internal (endogenous) sustained attention task, requiring participants to synchronise their manual responses to the rhythm of auditory pulses presented in an earlier phase. As previously documented, we found that action video game players displayed worse ability to maintain attention over time, as compared with non-action players. In striking contrast, intensive sports practice was associated with an increased ability to maintain attention over time. Overall, these findings unveil distinct cascading effects on sustained attention induced by doing sport and playing action video games. [ABSTRACT FROM AUTHOR]

Although affective and semantic word properties are known to independently influence our sensorimotor system, less is known about their interaction. We investigated this issue applying a data-driven mixed-effects regression approach, evaluating the impact of lexical-semantic properties on electrophysiological parameters, namely facial muscles activity (left corrugator supercilii, zygomaticus major, levator labii superioris) and heartbeat, during word processing. 500 Italian words were acoustically presented to 20 native-speakers, while electrophysiological signals were continuously recorded. Stimuli varied for affective properties, namely valence (the degree of word positivity), arousal (the amount of emotional activation brought by the word), and semantic ones, namely concreteness. Results showed that the three variables interacted in predicting both heartbeat and muscular activity. Specifically, valence influenced activation for lower levels of arousal. This pattern was further modulated by concreteness: the lower the word concreteness, the larger affective-variable impact. Taken together, our results provide evidence for bodily responses during word comprehension. Crucially, such responses were found not only for voluntary muscles, but also for the heartbeat, providing evidence to the idea of a common emotional motor system. The higher impact of affective properties for abstract words supports proposals suggesting that emotions play a central role in the grounding of abstract concepts. [ABSTRACT FROM AUTHOR]

Abstract The airframe noise of a 1:2 scaled aircraft model is investigated through a series of experiments in the hard walled closed test section of a large non-anechoic wind tunnel. A surface mounted phased microphone array is used to acquire the wall pressure fluctuations generated by the interaction of the wind tunnel flow and the propagating noise. Data from two measurement campaigns are analysed. The wind tunnel acoustic behaviour and the array performance are first assessed evaluating the results obtained from a reference sound source installed in the centre of the test section. The combination of different airflow speeds, array positions and sound sources are tested. The airframe noise is evaluated acquiring pressure fluctuations in different configurations. The main parameters varied during the tests are the flight configuration, the speed of the airflow, the incidence angle of the model and the position of the microphone array. Data are processed and then analysed in the frequency domain and using a conventional beamforming algorithm to retrieve the sound source maps over the regions of interest. Source maps are deconvolved with a CLEAN-SC routine and single source contributions determined through integration of auto-powers. The resulting spectra are finally scaled determining the exponents of the pertinent scaling laws. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prevalence and outcomes of surgery for lumbar disc herniation in professional football players. Design: Retrospective case series. Setting: Sports rehabilitation center. Participants: A period of 10 seasons of the Italian Football First League (Serie A) was retrospectively investigated. Thirty-three teams (for a total of 1960 players) took turns in the 10 seasons, and 42 team doctors were requested to provide information about the number of players who underwent surgery for lumbar disc herniation. Intervention: Survey distributed to team doctors. Main outcome measures: Prevalence and match incidence of the lumbar discectomy, proportion of players returning to competition after surgery, recovery time and preintervention and postintervention number of appearances in official matches were analyzed. Results: Eleven players underwent the surgical intervention during the considered period. The prevalence of the surgical treatment was 0.6%, whereas the match incidence was 0.09 cases/1000 match hours. All players returned to competitions 6.0 (3.5-7.7) months after surgery, with no significant difference between different roles. The number of appearances in official matches was comparable during the seasons before and after surgery. Conclusions: The lumbar discectomy must be considered a rare surgical procedure performed in professional football players. All players returned to competitions after surgery. The postintervention number of appearances in official matches was comparable with the preintervention one. [ABSTRACT FROM AUTHOR]

Purpose: We present a patient with adrenal Cushing’s syndrome causing steroid myopathy. The purpose of the case report is to illustrate the clinical usefulness of quantitative muscle ultrasonography for the assessment of glucocorticoid-induced changes in muscle mass (MM) and structure. Methods: Assessments of physical performance, muscle strength, MM (i.e., total body skeletal MM, appendicular skeletal MM, and thickness of lower limb muscles), and muscle structure (i.e., echo intensity of lower limb muscles) were performed in the patient both in the active phase of the disease (preoperatively) and 6 months after surgical intervention (postoperatively). Results: Muscle strength, physical performance, and MM were low both preoperatively and postoperatively. We also found preoperatively an increased echo intensity that normalized postoperatively. Conclusions: Clinical implications of these findings are double-fold. First, although the muscle structure can recover quickly in steroid myopathy patients, the recovery of MM may take months to years. Second, we show that muscle echo intensity can be useful to track the progression of steroid myopathy overtime and may help to indicate early response to therapeutic interventions. Further prospective studies are needed to confirm the value of muscle echo intensity in patients with endogenous or exogenous Cushing’s syndrome presenting with steroid myopathy. [ABSTRACT FROM AUTHOR]

Over the past few years, an increasing number of studies have shown that playing action video games can have positive effects on tasks that involve attention and visuo-spatial cognition (e.g., visual search, enumeration tasks, tracking multiple objects). Although playing action video games can improve several cognitive functions, the intensive interaction with the exciting, challenging, intrinsically stimulating and perceptually appealing game environments may adversely affect other functions, including the ability to maintain attention when the level of stimulation is not as intense. This study investigated whether a relationship existed between action video gaming and sustained attention performance in a sample of 45 Italian teenagers. After completing a questionnaire about their video game habits, participants were divided into Action Video Game Player (AVGP) and Non–Action Video Game Player (NAVGP) groups and underwent cognitive tests. The results confirm previous findings of studies of AVGPs as they had significantly enhanced performance for instantly enumerating a set of items. Nevertheless, we found that the drop in performance over time, typical of a sustained attention task, was significantly greater in the AVGP compared with the NAVGP group. This result is consistent with our hypothesis and demonstrates a negative effect of playing action video games. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to understand the effects of short-term glucocorticoid administration in healthy subjects.Methods: Five healthy men received dexamethasone (8 mg/day) for 7 days. Vastus lateralis muscle biopsy and knee extension torque measurement were performed before and after administration. A large number of individual muscle fibers were dissected from the biopsy samples (pre-administration: n = 165, post-administration: n = 177).Results: Maximal knee extension torque increased after administration (∼ 13%), whereas both type 1 and type 2A fibers had decreased cross-sectional area (type 1: ∼ 11%, type 2A: ∼ 17%), myosin loss (type 1: ∼ 18%, type 2A: ∼ 32%), and loss of specific force (type 1: ∼ 24%, type 2A: ∼ 33%), which were preferential for fast fibers.Conclusion: Short-term dexamethasone administration in healthy subjects elicits quantitative and qualitative adaptations of muscle fibers that precede (and may predict) the clinical appearance of myopathy in glucocorticoid-treated subjects. [ABSTRACT FROM AUTHOR]

This narrative review provides an overview of the application of endoscopic ultrasound-guided biliary drainage (EUS-BD), including EUS-guided gallbladder drainage (EUS-GBD), for the treatment of malignant biliary obstruction. EUS-BD has demonstrated excellent technical and clinical success rates, with lower rates of adverse events when compared with percutaneous trans-hepatic biliary drainage (PTBD). EUS-BD is currently the preferred alternative technique for biliary drainage (BD) in patients with distal malignant biliary obstruction (DMBO) after failed endoscopic retrograde cholangiopancreatography (ERCP). Particularly, this review will focus on EUS-BD performed with the use of lumen apposing metal stent (LAMS). The introduction of these innovative devices, followed by the advent of electrocautery-enhanced LAMS (EC-LAMS), gave the procedure a great technical implementation and a widespread application. [ABSTRACT FROM AUTHOR]

Non-technical summary There is still a debate on the origin of muscle cramps, which may be from the peripheral or the central nervous system. In this study we show that cramps electrically induced in the abductor hallucis of healthy men do occur with and without a proximal nerve block. However, cramps elicited during the nerve block required greater stimulation frequency, lasted for a substantially shorter interval, and presented different motor unit behaviour with respect to cramps induced without the block. These findings suggest the relevance of spinal involvement in both the origin and sustenance of muscle cramps. [ABSTRACT FROM AUTHOR]

To explore the efficacy of muscle motor point stimulation in eliciting muscle cramps, 11 subjects underwent eight sessions of electrical stimulation of the following muscles bilaterally: abductor hallucis flexor hallucis brevis, and both heads of the gastrocnemius muscles. Bursts of 150 square wave stimuli (duration: 152 μs; current intensity: 30% supramaximal) were applied. The stimulation frequency was increased from 4 pulses per second (pps) at increments of 2 pps until a cramp was induced. The number of cramps that could be elicited was smaller in flexor hallucis brevis than in abductor hallucis (16 vs. 22 out of 22 trials each; P < 0.05) and in the lateral gastrocnemius than in the medial gastrocnemius (5 vs. 20 out of 22 trials each; P < 0.0001). We show that leg and foot muscles have different cramp susceptibility, and the intermuscle variability in the elicitability profile for electrically induced cramps supports the use of the proposed method for cramp research. Muscle Nerve, 2009 [ABSTRACT FROM AUTHOR]

The aims of this study were to investigate age-related changes in total body skeletal muscle mass (TBSMM) and the between-limb asymmetry in lean mass in a large sample of adults. Demographic, anthropometric, and DXA-derived data of National Health and Nutrition Examination Survey participants were considered. The sample included 10,014 participants of two ethnic groups (Caucasians and African Americans). The age-related decline of TBSMM absolute values was between 5% and 6% per decade in males and between 4.5% and 5.0% per decade in females. The adjustment of TBSMM for body surface area (TB-MAXI) showed that muscle mass peaked in the second decade and decreased progressively during the subsequent decades. The following thresholds were identified to distinguish between low and normal TB-MAXI: (i) 10.0 kg/m2 and 11.0 kg/m2 in Caucasian and African American females; and (ii) 12.5 kg/m2 and 14.5 kg/m2 in Caucasian and African American males. The lean asymmetry indices were higher for the lower limbs compared with the upper limbs and were higher for males compared with females. In conclusion, the present study proposes the TB-MAXI and lean asymmetry index, which can be used (and included in DXA reports) as clinically relevant markers for muscle amount and lean distribution. [ABSTRACT FROM AUTHOR]

Experimental methods involving painful electrical stimulation of a peripheral nerve showed the existence of a minimum stimulation frequency capable of inducing cramp, termed 'threshold frequency' (TF). Our aim was to test an alternative method to induce fasciculations and cramps electrically. Two daily sessions of electrical stimulation of the abductor hallucis muscle were performed in 19 volunteers on 3 days: stimulation trains of 150 monophasic square pulses (duration 152 μs) of increasing frequency (current intensity 30% higher than maximal; frequency of the first trial, 4 pps; recovery between trials, 1 min) were delivered to the main muscle motor point until a cramp developed. Once a cramp was induced the protocol was repeated after 30 min. To verify by electromyography that cramp occurred, a surface electrode array was placed between the motor point and the distal tendon. Ambient and skin temperature were kept constant in all sessions. Fasciculations and cramps were elicited in all subjects. We observed the following median (interquartile range) values of TF: day 1 (session 1), 13 (6) pps; day 1 (session 2), 16 (4) pps; day 2 (session 1), 16 (6) pps; day 2 (session 2), 18 (6) pps; day 3 (session 1), 17 (4) pps; day 3 (session 2), 18 (8) pps. TF intersession intraclass correlation coefficients were 0.82, 0.92, and 0.90 for days 1, 2, and 3, respectively. TF interday intraclass correlation coefficient was 0.85. The absence of pain due to the stimulation and the demonstration of TF reliability support the use of our method for the study of involuntary muscle phenomena. Muscle Nerve, 2007 [ABSTRACT FROM AUTHOR]

Simple Summary: EUS-guided biliary drainage (EUS-BD) has proven effective in the palliation of malignant biliary obstructions. There are several methods for obtaining EUS-guided biliary drainage when endoscopic retrograde cholangiopancreatography (ERCP) fails. To date, EUS-BD, along with the well-established role of percutaneous transhepatic biliary drainage (PTBD) and surgical hepaticojejunostomy, has been demonstrated as a viable palliative treatment option in these patients. There are no specific guidelines with regard to the optimal drainage method. In this review, we compare all these techniques, demonstrating that EUS-BD in expert hands represents a minimally invasive and effective method in the palliative treatment of patients with malignant biliary obstruction. Malignant biliary obstruction (MBO) is a challenging medical problem that often negatively impacts the patient's quality of life (QoL), postoperative complications, and survival rates. Endoscopic approaches to biliary drainage are generally performed by ERCP or, in selected cases, with a percutaneous transhepatic biliary drainage (PTBD). Recent advances in therapeutic endoscopic ultrasound (EUS) allow drainage where previous methods have failed. EUS has evolved from a purely diagnostic technique to one that allows a therapeutic approach in the event of ERCP failure in distal MBO. Moreover, the introduction of dedicated accessories and prostheses for EUS-guided transmural biliary drainage (EUS-BD) made these procedures more successful with regard to technical success, clinical outcomes and reduction of adverse events (AEs). Finally, lumen-apposing metal stents (LAMS) have improved the therapeutic role of the EUS. Subsequently, the electrocautery enhanced tip of the LAMS (EC-LAMS) allows a direct access of the delivery system to the target lumen, thereby simplifying and reducing the EUS-BD procedure time. EUS-BD using LAMS and EC-LAMS has proven effective and safe with a low rate of AEs. This review aims to evaluate biliary drainage techniques in malignant obstruction, focusing on the role of EUS biliary drainage by LAMS. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are covalently closed RNA molecules widely expressed in eukaryotes and deregulated in several pathologies, including cancer. Many studies point to their activity as microRNAs (miRNAs) and protein sponges; however, we propose a function based on circRNA-mRNA interaction to regulate mRNA fate. We show that the widely tumor-associated circHIPK3 directly interacts in vivo with the BRCA1 mRNA through the back-splicing region in human cancer cells. This interaction increases BRCA1 translation by competing for the binding of the fragile-X mental retardation 1 protein (FMRP) protein, which we identified as a BRCA1 translational repressor. CircHIPK3 depletion or disruption of the circRNA-mRNA interaction decreases BRCA1 protein levels and increases DNA damage, sensitizing several cancer cells to DNA-damage-inducing agents and rendering them susceptible to synthetic lethality. Additionally, blocking FMRP interaction with BRCA1 mRNA with locked nucleic acid (LNA) restores physiological protein levels in BRCA1 hemizygous breast cancer cells, underscoring the importance of this circRNA-mRNA interaction in regulating DNA-damage response. [Display omitted] • circHIPK3 and FMRP compete for a direct site-specific binding to the BRCA1 mRNA • circHIPK3 promotes BRCA1 expression, preventing FMRP-mediated translational inhibition • circHIPK3- BRCA1 interaction disruption sensitizes cancer cells to DNA-damaging drugs • FMRP- BRCA1 -binding disruption restores normal BRCA1 levels in BRCA1 hemizygous cells Grelloni et al. demonstrate that the tumor-associated circular RNA circHIPK3 and the RNA-binding protein FMRP compete for site-specific binding to the BRCA1 mRNA. CircHIPK3, by interacting with the BRCA1 transcript, prevents FMRP-mediated translational inhibition, thereby increasing BRCA1 protein levels. These interactions represent novel therapeutic targets to modulate BRCA1 levels. [ABSTRACT FROM AUTHOR]

Recent observations of X-ray pulsars (XRPs) performed by the Imaging X-ray Polarimetry Explorer (IXPE) have made it possible to investigate the intricate details of these objects in a new way, thanks to the added value of X-ray polarimetry. Here we present the results of the IXPE observations of SMC X-1, a member of the small group of XRPs displaying super-orbital variability. SMC X-1 was observed by IXPE three separate times during the high state of its super-orbital period. The observed luminosity in the 2–8 keV energy band of L ∼ 2 × 1038 erg s−1 makes SMC X-1 the brightest XRP ever observed by IXPE. We detect significant polarization in all three observations, with values of the phase-averaged polarization degree (PD) and polarization angle (PA) of 3.2 ± 0.8% and 97° ±8° for Observation 1, 3.0 ± 0.9% and 90° ±8° for Observation 2, and 5.5 ± 1.1% and 80° ±6° for Observation 3, for the spectro-polarimetric analysis. The observed PD shows an increase over time with decreasing luminosity, while the PA decreases in decrements of ∼10°. The phase-resolved spectro-polarimetric analysis reveals significant detection of polarization in three out of seven phase bins, with the PD ranging between ∼2% and ∼10%, and a corresponding range in the PA from ∼70° to ∼100°. The pulse-phase resolved PD displays an apparent anti-correlation with the flux. Using the rotating vector model, we obtain constraints on the pulsar's geometrical properties for the individual observations. The position angle of the pulsar displays an evolution over time supporting the idea that we observe changes related to different super-orbital phases. Scattering in the wind of the precessing accretion disk may be responsible for the behavior of the polarimetric properties observed during the high-state of SMC X-1's super-orbital period. [ABSTRACT FROM AUTHOR]

Discovery of pulsations from a number of ultra-luminous X-ray (ULX) sources proved that accretion onto neutron stars can produce luminosities exceeding the Eddington limit by several orders of magnitude. The conditions necessary to achieve such high luminosities as well as the exact geometry of the accretion flow in the neutron star vicinity are, however, a matter of debate. The pulse phase-resolved polarization measurements that became possible with the launch of the Imaging X-ray Polarimetry Explorer (IXPE) can be used to determine the pulsar geometry and its orientation relative to the orbital plane. They provide an avenue to test different theoretical models of ULX pulsars. In this paper we present the results of three IXPE observations of the first Galactic ULX pulsar Swift J0243.6+6124 during its 2023 outburst. We find strong variations in the polarization characteristics with the pulsar phase. The average polarization degree increases from about 5% to 15% as the flux dropped by a factor of three in the course of the outburst. The polarization angle (PA) as a function of the pulsar phase shows two peaks in the first two observations, but changes to a characteristic sawtooth pattern in the remaining data set. This is not consistent with a simple rotating vector model. Assuming the existence of an additional constant polarized component, we were able to fit the three observations with a common rotating vector model and obtain constraints on the pulsar geometry. In particular, we find the pulsar angular momentum inclination with respect to the line of sight of ip = 15°–40°, the magnetic obliquity of θp = 60°–80°, and the pulsar spin position angle of χp ≈ −50°, which significantly differs from the constant component PA of about 10°. Combining these X-ray measurements with the optical PA, we find evidence for at least a 30° misalignment between the pulsar angular momentum and the binary orbital axis. [ABSTRACT FROM AUTHOR]

• Perceptually-grounded properties of constituents affect compound processing. • Automatic perceptually-grounded conceptual combination irrespective of task demands. • We propose a computational model of perceptually-grounded conceptual combination. Previous studies found that an automatic meaning-composition process affects the processing of morphologically complex words, and related this operation to conceptual combination. However, research on embodied cognition demonstrates that concepts are more than just lexical meanings, rather being also grounded in perceptual experience. Therefore, perception-based information should also be involved in mental operations on concepts, such as conceptual combination. Consequently, we should expect to find perceptual effects in the processing of morphologically complex words. In order to investigate this hypothesis, we present the first fully-implemented and data-driven model of perception-based (more specifically, vision-based) conceptual combination, and use the predictions of such a model to investigate processing times for compound words in four large-scale behavioral experiments employing three paradigms (naming, lexical decision, and timed sensibility judgments). We observe facilitatory effects of vision-based compositionality in all three paradigms, over and above a strong language-based (lexical and semantic) baseline, thus demonstrating for the first time perceptually grounded effects at the sub-lexical level. This suggests that perceptually-grounded information is not only utilized according to specific task demands but rather automatically activated when available. [ABSTRACT FROM AUTHOR]

Musculoskeletal disorders are debilitating conditions that significantly impair the state of health, especially in elderly subjects. A pathological triad of inter-related disorders that are highly prevalent in the elderly consists of the following main "components": sarcopenia, tendinopathies, and arthritis. The aim of this review is to critically appraise the literature relative to the different disorders of this triad, in order to highlight the pathophysiological common denominator and propose strategies for personalized clinical management of patients presenting with this combination of musculoskeletal disorders. Their pathophysiological common denominator is represented by progressive loss of (focal or generalized) neuromuscular performance with a risk of adverse outcomes such as pain, mobility disorders, increased risk of falls and fractures, and impaired ability or disability to perform activities of daily living. The precise management of these disorders requires not only the use of available tools and recently proposed operational definitions, but also the development of new tools and approaches for prediction, diagnosis, monitoring, and prognosis of the three disorders and their combination. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is little evidence on intra-articular (IA) treatment in knee osteoarthritis (KOA) and there is a lack of long-term follow-up studies. OBJECTIVE: To assess the long-term effectiveness and safety of IA oxygen-ozone (O 2 O 3) and hyaluronic acid (HA) in terms of functioning in KOA patients over a 31-week period. METHODS: Patients aged ⩾ 60 years with KOA were randomly allocated to receive 4 IA knee injections (1/week) of O 2 O 3 or HA (T0–T3) and a follow-up visit 4 weeks after the fourth injection (T4). In this extension study we assessed VAS and safety in patients with Visual Analogue Scale (VAS) ⩾ 4 at the at 6-month follow-up visit (T5), undergoing a second treatment cycle (T5–T8) and 1-month follow-up visit (T9). RESULTS: Forty-two patients (aged 70.5 ± 5.8 years) were randomly allocated to O 2 O 3 (n = 22) or HA group (n = 20). Twenty-three underwent another IA cycle: 12 (54.6%) in the O 2 O 3 group and 11 (55.0%) in the HA group. Both groups showed significant reduction in VAS (p < 0.013) compared to baseline during both cycles. At follow-up visits (T4 and T9), VAS was significantly lower in the HA group (p < 0.013). There were no differences in adverse events occurrence between groups. CONCLUSIONS: IA O 2 O 3 might be comparable to HA in terms of effectiveness and safety in reducing pain in KOA patients, although at both follow-up visits (T4 and T9) VAS was significantly lower in the HA group. [ABSTRACT FROM AUTHOR]

Objectives: Endoscopic retrograde cholangiopancreatography (ERCP) represents the gold standard for jaundice palliation in patients with distal malignant biliary obstruction (DMBO). Biliary drainage using electrocautery lumen apposing metal stent (EC‐LAMS) is currently a well‐established procedure when ERCP fails. In a palliative setting the endoscopic ultrasound‐guided gallbladder drainage (EUS‐GBD) could represent an easy and valid option. We performed a prospective study with a new EC‐LAMS with the primary aim to assess the clinical success rate of EUS‐GBD as a first‐line approach to the palliation of DMBO. Methods: In all, 37 consecutive patients undergoing EUS‐GBD with a new EC‐LAMS were prospectively enrolled. Clinical success was defined as bilirubin level decrease >15% within 24 h and >50% within 14 days after EC‐LAMS placement. Results: The mean age was 73.5 ± 10.8 years; there were 17 male patients (45.9%). EC‐LAMS placement was technically feasible in all patients (100%) and the clinical success rate was 100%. Four patients (10.8%) experienced adverse events, one bleeding, one food impaction, and two cystic duct obstructions because of disease progression. No stent‐related deaths were observed. The mean hospitalization was 7.7 ± 3.4 days. Median overall survival was 4 months (95% confidence interval 1–8). Conclusion: Endoscopic ultrasound‐guided gallbladder drainage with the new EC‐LAMS is a valid option in palliative endoscopic biliary drainage as a first‐step approach in low survival patients with malignant jaundice unfit for surgery. A smaller diameter EC‐LAMS should be preferred, particularly if the drainage is performed through the stomach, to avoid potential food impaction, which could result in stent dysfunction. [ABSTRACT FROM AUTHOR]

Endoscopic retrograde cholangiopancreatography (ERCP) is considered the preferred method for managing biliary obstructions. However, the prevalence of surgically modified anatomies often poses challenges, making the standard side-viewing duodenoscope unable to reach the papilla in most cases. The increasing instances of surgically altered anatomies (SAAs) result from higher rates of bariatric procedures and surgical interventions for pancreatic malignancies. Conventional ERCP with a side-viewing endoscope remains effective when there is continuity between the stomach and duodenum. Nonetheless, percutaneous transhepatic biliary drainage (PTBD) or surgery has historically been used as an alternative for biliary drainage in malignant or benign conditions. The evolving landscape has seen various endoscopic approaches tailored to anatomical variations. Innovative methodologies such as cap-assisted forward-viewing endoscopy and enteroscopy have enabled the performance of ERCP. Despite their utilization, procedural complexities, prolonged durations, and accessibility challenges have emerged. As a result, there is a growing interest in novel enteroscopy and endoscopic ultrasound (EUS) techniques to ensure the overall success of endoscopic biliary drainage. Notably, EUS has revolutionized this domain, particularly through several techniques detailed in the review. The rendezvous approach has been pivotal in this field. The antegrade approach, involving biliary tree puncturing, allows for the validation and treatment of strictures in an antegrade fashion. The EUS-transmural approach involves connecting a tract of the biliary system with the GI tract lumen. Moreover, the EUS-directed transgastric ERCP (EDGE) procedure, combining EUS and ERCP, presents a promising solution after gastric bypass. These advancements hold promise for expanding the horizons of comprehensive and successful biliary drainage interventions, laying the groundwork for further advancements in endoscopic procedures. [ABSTRACT FROM AUTHOR]

We describe IXPE polarization observations of the pulsar wind nebula (PWN) MSH 15−52, the "Cosmic Hand." We find X-ray polarization across the PWN, with B -field vectors generally aligned with filamentary X-ray structures. High-significance polarization is seen in arcs surrounding the pulsar and toward the end of the "jet," with polarization degree PD > 70%, thus approaching the maximum allowed synchrotron value. In contrast, the base of the jet has lower polarization, indicating a complex magnetic field at significant angle to the jet axis. We also detect significant polarization from PSR B1509−58 itself. Although only the central pulse phase bin of the pulse has high individual significance, flanking bins provide lower-significance detections and, in conjunction with the X-ray image and radio polarization, can be used to constrain rotating vector model solutions for the pulsar geometry. [ABSTRACT FROM AUTHOR]

Inflammatory bowel diseases (IBDs) are chronic, relapsing inflammatory disorders of the gastrointestinal tract, frequently associated with extraintestinal manifestations (EIMs) that can severely affect IBD patients' quality of life, sometimes even becoming life-threatening. Respiratory diseases have always been considered a rare and subsequently neglected extraintestinal manifestations of IBD. However, increasing evidence has demonstrated that respiratory involvement is frequent in IBD patients, even in the absence of respiratory symptoms. Airway inflammation is the most common milieu of IBD-related involvement, with bronchiectasis being the most common manifestation. Furthermore, significant differences in prevalence and types of involvement are present between Crohn's disease and ulcerative colitis. The same embryological origin of respiratory and gastrointestinal tissue, in addition to exposure to common antigens and cytokine networks, may all play a potential role in the respiratory involvement. Furthermore, other causes such as drug-related toxicity and infections must always be considered. This article aims at reviewing the current evidence on the association between IBD and respiratory diseases. The purpose is to raise awareness of respiratory manifestation among IBD specialists and emphasize the need for identifying respiratory diseases in early stages to promptly treat these conditions, avoid worsening morbidity, and prevent lung damage. [ABSTRACT FROM AUTHOR]

Quantitative, data-driven models for mental representations have long enjoyed popularity and success in psychology (e.g., distributional semantic models in the language domain), but have largely been missing for the visual domain. To overcome this, we present ViSpa (Vision Spaces), high-dimensional vector spaces that include vision-based representation for naturalistic images as well as concept prototypes. These vectors are derived directly from visual stimuli through a deep convolutional neural network trained to classify images and allow us to compute vision-based similarity scores between any pair of images and/or concept prototypes. We successfully evaluate these similarities against human behavioral data in a series of large-scale studies, including off-line judgments—visual similarity judgments for the referents of word pairs (Study 1) and for image pairs (Study 2), and typicality judgments for images given a label (Study 3)—as well as online processing times and error rates in a discrimination (Study 4) and priming task (Study 5) with naturalistic image material. ViSpa similarities predict behavioral data across all tasks, which renders ViSpa a theoretically appealing model for vision-based representations and a valuable research tool for data analysis and the construction of experimental material: ViSpa allows for precise control over experimental material consisting of images and/or words denoting imageable concepts and introduces a specifically vision-based similarity for word pairs. To make ViSpa available to a wide audience, this article (a) includes (video) tutorials on how to use ViSpa in R and (b) presents a user-friendly web interface at http://vispa.fritzguenther.de. [ABSTRACT FROM AUTHOR]

Gastroesophageal reflux disease has a high incidence and prevalence in the general population. Clinical manifestations are heterogenous, and so is the response to medical treatment. Proton pump inhibitors are still the most common agents used to control reflux symptoms and for healing esophagitis, but they are not a one-size-fits-all solution for the disease. Patients with persistent troublesome symptoms despite medical therapy, those experiencing some adverse drug reaction, or those unwilling to take lifelong medications deserve valid alternatives. Anti-reflux Nissen fundoplication is an effective option, but the risk of adverse events has limited its spread. In recent years, advancements in therapeutic endoscopy have been made, and three major endoluminal alternatives are now available, including (1) the delivery of radiofrequency energy to the esophago–gastric junction, (2) transoral incisionless fundoplication (TIF), and (3) anti-reflux mucosal interventions (ARMI) based on mucosal resection (ARMS) and mucosal ablation (ARMA) techniques to remodel the cardia. Endoscopic techniques have shown interesting results, but their diffusion is still limited to expert endoscopists in tertiary centers. This review discusses the state of the art in the endoscopic approach to gastroesophageal reflux disease. [ABSTRACT FROM AUTHOR]

Objective: About 20% of sporadic medullary thyroid carcinomas (MTC) have no RET/RAS somatic alterations or other known gene alterations. The aim of this study was to investigate RET/RAS-negative MTC for the presence of NF1 alterations. Methods: We studied 18 sporadic RET/RAS-negative MTC cases. Next-generation sequencing (NGS) of tumoral and blood DNA was performed using a custom panel including the entire coding region of the NF1 gene. The effect of NF1 alterations on the transcripts was characterized by reverse transcriptase-polymerase chain reaction (RT-PCR), and the loss of heterozygosity (LOH) of the other NF1 allele was investigated with Multiplex Ligation-dependent Probe Amplification (MLPA). Results: Two cases showed biallelic inactivation of NF1 with a prevalence of about 11% of RET/RAS-negative cases. In a patient affected by neurofibromatosis, there was a somatic intronic point mutation determining the transcript alteration in 1 allele and a germline LOH in the other. In a second patient, we described that both the point mutation and the LOH were somatic events; this latter finding shows, for the first time, a driver role of NF1 inactivation in MTC independent of RET/RAS alterations and the presence of neurofibromatosis. Conclusions: About 11% of our series of sporadic RET/RAS-negative MTC harbor biallelic inactivation of the NF1 suppressor gene also regardless of neurofibromatosis status. According to our results, NF1 alterations should be searched in all RET/RAS-negative MTC as possible drivers. Moreover, this finding reduces the number of negative sporadic MTC and may have important clinical implications in the management of these tumors. [ABSTRACT FROM AUTHOR]

Increasing context heterogeneity has been found to reduce attention deployment towards an embedded target item. Heterogeneity in visual search tasks is typically induced by segmenting the background into several perceptual groups. In the present study, however, context heterogeneity was induced by varying whole-field heterogeneity, i.e., the degree of distractor variability within the entire context. This allowed us to (i) more gradually vary context heterogeneity, and (ii) investigate attention deployment on a whole-field scale. Results showed that both search performance and amplitude of the N2pc (lateralized ERP; posterior contralateral negativity in the N2 range) monotonically decreased with increasing context heterogeneity, which confirmed that there was less efficient attention deployment for more heterogeneous contexts. The amplitude of the bilateral N2 exhibited a U-shaped function, suggesting global perception for the lowest and highest levels of heterogeneity, but local processing for intermediate heterogeneity levels. Independent component analyses revealed an occipital ERP-contributing effective source cluster that may reflect stimulus representations on a saliency map. With increasing heterogeneity, these sources exhibited more theta band activity for distractors and less theta band activity for targets. Alpha band activity of a second component cluster varied with heterogeneity level, and low-theta/delta activity of a third source cluster distinguished target presence versus absence. In sum, our results suggest that independent brain sources contributed to the differential processing of heterogeneous versus homogeneous contexts. [ABSTRACT FROM AUTHOR]

We aimed to investigate the reproducibility and accuracy of Radiofrequency Echographic Multi-Spectrometry (REMS) for femoral BMD estimation and the reproducibility and discriminative power of the REMS-derived femoral fragility score. 175 patients with primary and disuse-related osteoporosis were recruited: one femoral Dual-energy X-ray Absorptiometry (DXA) scan and two femoral REMS scans were acquired. No significant test—retest differences were observed for all REMS-derived variables. The diagnostic concordance between DXA and REMS was 63% (Cohen's kappa = 0.31) in patients with primary osteoporosis and 13% (Cohen's kappa: −0.04) in patients with disuse-related osteoporosis. No significant difference was observed between REMS and DXA for either femoral neck BMD (mean difference between REMS and DXA: −0.015 g/cm2) or total femur BMD (mean difference: −0.004 g/cm2) in patients with primary osteoporosis. Significant differences between the two techniques were observed in patients with disuse-related osteoporosis (femoral neck BMD difference: 0.136 g/cm2; total femur BMD difference: 0.236 g/cm2). Statistically significant differences in the fragility score were obtained between the fractured and non-fractured patients for both populations. In conclusion, REMS showed excellent test-retest reproducibility, but the diagnostic concordance between DXA and REMS was between minimal and poor. Further studies are required to improve the REMS—derived estimation of femoral BMD. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnea syndrome (OSAS) is a serious, prevalent condition that has significant morbidity and mortality when untreated. It is strongly associated with obesity and is characterized by changes in the serum levels or secretory patterns of several hormones. Obese patients with OSAS show a reduction of both spontaneous and stimulated growth hormone (GH) secretion coupled to reduced insulin-like growth factor-I (IGF-I) concentrations and impaired peripheral sensitivity to GH. Hypoxemia and chronic sleep fragmentation could affect the sleep-entrained prolactin (PRL) rhythm. A disrupted Hypothalamus-Pituitary- Adrenal (HPA) axis activity has been described in OSAS. Some derangement in Thyroid-Stimulating Hormone (TSH) secretion has been demonstrated by some authors, whereas a normal thyroid activity has been described by others. Changes of gonadal axis are common in patients with OSAS, who frequently show a hypogonadotropic hypogonadism. Altogether, hormonal abnormalities may be considered as adaptive changes which indicate how a local upper airway dysfunction induces systemic consequences. The understanding of the complex interactions between hormones and OSAS may allow amulti-disciplinary approach to obese patients with this disturbance and lead to an effective management that improves quality of life and prevents associated morbidity or death. [ABSTRACT FROM AUTHOR]

The Imaging X-ray Polarimetry Explorer is a mission dedicated to the measurement of X-ray polarization from tens of astrophysical sources belonging to different classes. Expected to be launched at the end of 2021, the payload comprises three mirrors and three focal plane imaging polarimeters, the latter being designed and built in Italy. While calibration is always an essential phase in the development of high-energy space missions, for IXPE it has been particularly extensive both to calibrate the response to polarization, which is peculiar to IXPE, and to achieve a statistical uncertainty below the expected sensitivity. In this paper we present the calibration equipment that was designed and built at INAF-IAPS in Rome, Italy, for the calibration of the polarization-sensitive focal plane detectors on-board IXPE. Equipment includes calibration sources, both polarized and unpolarized, stages to align and move the beam, test detectors and their mechanical assembly. While all these equipments were designed to fit the specific needs of the IXPE Instrument calibration, their versatility could also be used in the future for other projects. [ABSTRACT FROM AUTHOR]

Subjects affected by ulcerative colitis and Crohn's disease with colonic localization have an increased risk of colorectal cancer (CRC). Surveillance colonoscopy is recommended by international guidelines as it can detect early-stage CRC. Based on previous evidence, in 2015 the Surveillance for Colorectal Endoscopic Neoplasia Detection and Management in Inflammatory Bowel Disease Patients International Consensus indicated dye chromoendoscopy (DCE) as the most effective technique for detecting dysplasia. However, advances in endoscopic technology such as high-definition colonoscopes and dye-less virtual chromoendoscopy (VCE) may change future practice. In this review, we summarize the available evidence on CRC surveillance in IBD, focusing on the emerging role of high-definition white light endoscopy (HD-WLE) and VCE over the standard DCE, and the current role of random biopsies. [ABSTRACT FROM AUTHOR]

Provides an overview of the service creation frameworks for Internet Telephony. Features of Internet Telephony; Importance of value added services for the survival of Internet Telephony; Description of a case study on high level graphical service creation environment.

Background: Skeletal muscle mass (SMM) and fat mass (FM) are essentially required for health and quality of life in older adults. Objective: To generate the best SMM and FM prediction models using machine learning models incorporating socioeconomic, lifestyle, and biochemical parameters and the urban hospital-based Ansan/Ansung cohort, and to determine relations between SMM and FM and metabolic syndrome and its components in this cohort. Methods: SMM and FM data measured using an Inbody 4.0 unit in 90% of Ansan/Ansung cohort participants were used to train seven machine learning algorithms. The ten most essential predictors from 1411 variables were selected by: (1) Manually filtering out 48 variables, (2) generating best models by random grid mode in a training set, and (3) comparing the accuracy of the models in a test set. The seven trained models' accuracy was evaluated using mean-square errors (MSE), mean absolute errors (MAE), and R² values in 10% of the test set. SMM and FM of the 31,025 participants in the Ansan/Ansung cohort were predicted using the best prediction models (XGBoost for SMM and artificial neural network for FM). Metabolic syndrome and its components were compared between four groups categorized by 50 percentiles of predicted SMM and FM values in the cohort. Results: The best prediction models for SMM and FM were constructed using XGBoost (R2 = 0.82) and artificial neural network (ANN; R2 = 0.89) algorithms, respectively; both models had a low MSE. Serum platelet concentrations and GFR were identified as new biomarkers of SMM, and serum platelet and bilirubin concentrations were found to predict FM. Predicted SMM and FM values were significantly and positively correlated with grip strength (r = 0.726) and BMI (r = 0.915, p < 0.05), respectively. Grip strengths in the high-SMM groups of both genders were significantly higher than in low-SMM groups (p < 0.05), and blood glucose and hemoglobin A1c in high-FM groups were higher than in low-FM groups for both genders (p < 0.05). Conclusion: The models generated by XGBoost and ANN algorithms exhibited good accuracy for estimating SMM and FM, respectively. The prediction models take into account the actual clinical use since they included a small number of required features, and the features can be obtained in outpatients. SMM and FM predicted using the two models well represented the risk of low SMM and high fat in a clinical setting. [ABSTRACT FROM AUTHOR]

• In all tested devices, the amplitude of the stimulation pulse depends on the stimulation frequency. • The shape of the stimulation pulse changes with the number of active outputs in 3 out of 4 devices. • All tested devices are characterized by a good temporal stability of the stimulation output. Different devices for mechano-acoustic muscle vibration became available on the market in the last ten years. Although the use of these vibrators is increasing in research and clinical settings, the features of their stimulation output were never described in literature. In this study we aimed to quantify and compare the stimulation output of the four most widespread pneumatic devices for focal muscle vibration available on the market. A piezoelectric pressure sensor was used to measure the pressure profile generated by the four selected devices in the following experimental conditions: i) measurement of the output changes associated with variations of the stimulation amplitude for three stimulation frequencies (100 Hz, 200 Hz, and 300 Hz); ii) measurement of the output changes during a 20-min long stimulation at constant frequency (300 Hz) and amplitude; iii) measurement of the output changes associated with the progressive activation of all stimulation channels at constant frequency (200 Hz) for different amplitudes. The maximum peak-to-peak amplitudes of the pressure waves were in the range 102 mbar - 369 mbar (below the maximum values declared by the different manufacturers). The shape of the pressure waves generated by the four devices was quasi-sinusoidal and asymmetric with respect to the atmospheric pressure. All output features had a remarkable intra- and inter-device variability. Further studies are required to support the technological improvement of the currently available devices and to focus the issues of vibration effectiveness, limitations, proper protocols, modalities of its application and assessment in neuromuscular training and rehabilitation. [ABSTRACT FROM AUTHOR]

Background: The demand for total hip arthroplasty (THA) is quickly rising given the escalating global incidence of hip osteoarthritis, and it is widely accepted that the post-surgery rehabilitation is key to optimize outcomes. The overall objective of this study is to evaluate the effectiveness of a new telerehabilitation solution, ReHub, for the physical function and clinical outcome improvement following THA. The specific aims of this manuscript are to describe the study design, protocol, content of interventions, and primary and secondary outcomes and to discuss the clinical rehabilitation impact of the expected experimental results.Methods/design: This prospective, randomized, controlled, parallel-group trial will include 56 patients who had undergone primary THA. Patients are randomized to a control group (standard rehabilitation during the 2-week stay in the rehabilitation clinic followed by 3 weeks of unsupervised home-based rehabilitation) or an experimental group (standard rehabilitation during the 2-week stay in the rehabilitation clinic followed by 3 weeks of home-based ReHub-assisted telerehabilitation). The primary outcome is physical performance assessed through the Timed Up-and-Go (TUG) test. Secondary outcomes include independence level, pain intensity, hip disability, hip range of motion, muscle strength, and patient's perception of clinical improvement.Discussion: Proving the clinical and cost-effectiveness of a home-based telerehabilitation program for physical and muscle function following THA could support its systematic incorporation in post-surgical rehabilitation protocols, which should be tailored to the individual and collective needs.Trial Registration: ClinicalTrial.gov NCT04176315 . Registered on 22 November 2019. [ABSTRACT FROM AUTHOR]

Ultrasonography allows non-invasive and real time-measurement of the visible cross-sectional area (CSA) of muscles, which is a clinically relevant descriptor of muscle size. The aim of this study was to develop and validate a fully automatic method called transverse muscle ultrasound analysis (TRAMA) for segmentation of the muscle in B-mode transverse ultrasound images and measurement of muscle CSA. TRAMA was tested on a database of 200 ultrasound images of the rectus femoris, vastus lateralis, tibialis anterior and medial gastrocnemius muscles. The automatic CSA measurements were compared with manual measurements obtained by two operators. There were no statistical differences between the automatic and manual measurements of CSA of the four muscles, and TRAMA performance was comparable to intra-operator variability in terms of the Dice similarity coefficient and Hausdorff distance between the automatic and manual segmentations. Compared with manual segmentation, the Dice similarity coefficient for the proposed method was always higher than 93%; the Hausdorff distance never exceeded 4 mm, and the maximum absolute error was 62 mm2. TRAMA is the first automated algorithm that analyzes and segments ultrasound scans of the muscle in the transverse plane. It can be adopted in future studies for automatic segmentation of muscle regions of interest to enhance and automatize a multitexture analysis of muscle structure. [ABSTRACT FROM AUTHOR]