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Let n, k ∈ N, T > 0, and F : [0,T]×(Rn)k → 2Rn be a lower semicontinuos and bounded multifunction with nonempty closed values. We prove that there exists a bounded and upper semicontinuous multifunction G : R × (Rn)k → 2Rn with nonempty compact convex values such that every generalized solution u : [0,T] → Rn of the differential inclusion u(k) ∈ G(t,u,u',...,u(k−1)) is a generalized solution to the differential inclusion u(k) ∈ F(t,u,u',...,u(k−1)). As an application, we prove an existence and qualitative result for the generalized solutions of the Cauchy problem associated to the inclusion u(k) ∈ F(t,u,u',...,u(k−1)). In particular, we prove that if F is lower semicontinuous and bounded with nonempty closed values, then the solution multifunction admits an upper semicontinuous multivalued selection with nonempty compact connected values. Finally, by applying the latter result, we prove an analogous existence and qualitative result for the generalized solutions of the Cauchy problem associated to the differential equation g(u(k)) = f(t,u,u',...,u(k−1)), where f is continuous. We only assume that g is continuous and locally nonconstant. [ABSTRACT FROM AUTHOR]

Harry, JR, Krzyszkowski, J, Harris, K, Chowning, L, Mackey, E, Bishop, C, and Barker, LA. Momentum-based load prescriptions: Applications to jump squat training. J Strength Cond Res 36(9): 2657–2662, 2022—Velocity-based training is often applied to ballistic exercises, like the barbell jump squat, to improve vertical jump performance. However, determining the ideal training load based on velocity data remains difficult because load prescriptions tend to be limited to subjective velocity loss thresholds, velocity ranges, or both. Using data from jump squats performed with 0, 15, 30, 45, and 60% of the 1-repetition maximum squat, we explored subjective and objective methods to determine the ideal training load. Specifically, we explored takeoff velocity and a related metric only recently discussed in the literature, system momentum (i.e., takeoff velocity multiplied by the mass of the athlete-load system). At the group level, an ideal training load could not be revealed objectively using takeoff velocity. With individual subjects, the process remained challenging using takeoff velocity. Conversely, an ideal training load could be revealed easily and objectively using system momentum at the group average and individual subject levels. System momentum at takeoff is well-suited to assist practitioners seeking to identify appropriate training loads for jump squat training and potentially other ballistic exercises. We suggest a pivot from velocity to system momentum when seeking to objectively establish training loads for the jump squat and related exercises. [ABSTRACT FROM AUTHOR]

We investigate the counter-intuitive initial decrease and subsequent increase in the Nusselt number Nu with increasing wall Reynolds number Rew in the sheared Rayleigh--Bénard (RB) system by studying the energy spectra of convective flux and turbulent kinetic energy for Rayleigh number Ra = 107, Prandtl number Pr = 1.0 and inverse Richardson numbers 0 ≤ 1/Ri ≤ 10. These energy spectra show two distinct high-energy regions corresponding to the large-scale superstructures in the bulk and small-scale structures in the boundary layer (BL) regions. A greater separation between these scales at the thermal BL height correlates to a higher Nu and indicates that the BLs are more turbulent. The minimum Nu, which occurs at 1/Ri = 1.0, is accompanied by the smallest separation between the large- and small-scale structures at the thermal BL height. At 1/Ri = 1.0, we also observe the lowest value of turbulent kinetic energy normalized with the square of friction velocity within the thermal BL. Additionally, we find that the domain size has a limited effect on the heat and momentum transfer in the sheared RB system as long as the domain can accommodate the small-scale convective structures at the thermal BL height, signifying that capturing the large-scale superstructures is not essential to obtain converged values of Nu and shear Reynolds number Reτ. When the domain is smaller than these small-scale convective structures, the overall heat and momentum transfer reduces drastically. [ABSTRACT FROM AUTHOR]

Despite being a standard treatment option in breast cancer, immune checkpoint inhibitors (ICIs) are only efficacious for a subset of patients. To gain a better understanding of the antitumor immune response in breast cancer, we examined the heterogeneity of CD8+ T cells in tumors, metastatic lymph nodes (mLNs), and peripheral blood from patients with early breast cancer (n = 131). Among tissue-resident memory CD8+ T (TRM) cells, including virus- and tumor-specific CD8+ T cells, CD39 expression was observed in a tumor-specific and exhausted subpopulation in both tumors and mLNs. CD39+ TRM cells from tumors and mLNs exhibited a phenotypic similarity and clonally overlapped with each other. Moreover, tumor or mLN CD39+ TRM cells clonally overlapped with CD39− TRM and non-TRM cells in the same compartment, implying a tissue-specific differentiation process. These inter-subpopulationally overlapping CD39+ TRM clonotypes were frequently detected among effector memory CD8+ T cells in peripheral blood, suggesting a systemic clonal overlap. CD39+ TRM cell enrichment was heterogeneous among molecular subtypes of breast cancer, which is associated with the different role of antitumor immune responses in each subtype. In vitro blockade of PD-1 and/or CTLA-4 effectively restored proliferation of CD39+ TRM cells and enhanced cytokine production by CD8+ T cells from tumors or mLNs, particularly in the presence of CD39+ TRM enrichment. This suggests that CD39+ TRM cells have a capacity for functional restoration upon ICI treatment. Thus, our study indicates that CD39+ TRM cells with a clonal overlap across compartments are key players in antitumor immunity in breast cancer. Reinvigorate your CD39+ TRM: Immune checkpoint blockade (ICB) has only displayed efficacy in some subsets of patients with breast cancer, yet it is unclear why. Here, Lee et al. examined tissue-resident memory T cells (TRM) in the tumors, lymph nodes, and blood of patients with early breast cancer, finding that tumor-specific CD8+ TRM expressed CD39, CD69, and CD103. These CD39+ TRM displayed an exhausted phenotype and overlapping TCR clonality in tumors and lymph nodes. CD39+ TRM were enriched in triple-negative breast cancer (TNBC) samples, correlating to overall survival of patients with TNBC, and could be reinvigorated from exhaustion with the addition of ICB ex vivo. Together, these data suggest that patients with TNBC with high CD39+ TRM signatures might be good candidates for ICB treatment. [ABSTRACT FROM AUTHOR]

The last few years have increasingly emphasized the need to develop new active antiviral products obtained from artificial synthesis processes using nanomaterials, but also derived from natural matrices. At the same time, advanced computational approaches have found themselves fundamental in the repurposing of active therapeutics or for reducing the very long developing phases of new drugs discovery, which represents a real limitation, especially in the case of pandemics. The first part of the review is focused on the most innovative nanomaterials promising both in the field of therapeutic agents, as well as measures to control virus spread (i.e., innovative antiviral textiles). The second part of the review aims to show how computer-aided technologies can allow us to identify, in a rapid and therefore constantly updated way, plant-derived molecules (i.e., those included in terpenoids) potentially able to efficiently interact with SARS-CoV-2 cell penetration pathways. [ABSTRACT FROM AUTHOR]

A scaling theory for the passive scalar transport in Couette flow, i.e. the flow between two parallel plates moving with different velocities, is proposed. This flow is determined by the bulk Reynolds number Reb and the Prandtl number Pr. In the turbulent regime, for moderate shear Reynolds number Reτ and moderate Pr, we derive that the passive scalar transport characterised by the Nusselt number Nu scales as Nu ∼ Pr1/2Re² τReb−1. We then use the well-established scaling for the friction coefficient Cf ∼ Reb−1/4 (corresponding to a shear Reynolds number Reτ ∼ Reb7/8) which holds reasonably well within the range 3 × 10³ ≤ Reb ≤105, to obtain Nu ∼ Pr1/2Reb3/4 for the Nusselt number scaling. The theoretical results are tested against direct numerical simulations of Couette flows for the parameter ranges 81≤ Reb≤ 22361 and 0.1 ≤Pr ≤10, finding good agreement. Analyses of the numerically obtained turbulent flow fields confirm logarithmic mean wall-parallel profiles of the velocity and the passive scalar in the inertial sublayer. [ABSTRACT FROM AUTHOR]

We perform direct numerical simulations to study the effect of the gravity centre offset in spherical Rayleigh-Bénard convection. When the gravity centre is shifted towards the south, we find that the shift of the gravity centre has a pronounced influence on the flow structures. At low Rayleigh number Ra, a steady-state large-scale meridional circulation induced by the baroclinic imbalance, created by the misalignment of the gravity potentials and isotherms, is formed. At high Ra, an energetic jet is created on the northern side of the inner sphere that is directed towards the outer sphere. The large-scale circulation induces a strong co-latitudinal dependence in the local heat flux. Nevertheless, the global heat flux is not affected by the changes in the large-scale flow organization induced by the gravity centre offset. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate associations between, and within, drop jump (DJ) neuromuscular performance (NMP) qualities and maximal horizontal deceleration ability. We also compared DJ NMP qualities in "high" versus "low" horizontal deceleration ability athletes. Twenty-nine university athletes performed: (1) DJs on force plates from 20 (DJ20) and 40 cm (DJ40) heights and (2) maximal horizontal deceleration, measured using radar, following a 20 m acceleration. Maximal horizontal deceleration was evaluated using deceleration (HDEC; m·s−2), across the entire deceleration phase and during early and late deceleration sub-phases. Of the DJ variables assessed, DJ20 and DJ40 reactive strength index (RSI) and concentric mean force had the largest correlations with HDEC (r = −0.54 to −0.61) and the largest differences between high and low HDEC groups (d = 1.20 to 1.40). These correlations were stronger with the early than late HDEC sub-phase (r = −0.54 to −0.66 vs. r = −0.24 to −0.40). Notably, eccentric mean force in DJ40 had large correlations with both DJ20 and DJ40 concentric mean force (r = 0.67 to 0.77), whereas at DJ20 these correlations were small (r = 0.22 to 0.40). Similarly, DJ40 eccentric mean force had a much larger difference between the high and low HDEC groups than DJ20 (d = 1.11 vs. 0.51). These findings suggest DJ RSI from either height may be used as a proxy for HDEC ability, while DJ kinetic analyses should use a higher height to distinguish those with a better capacity to generate eccentric braking forces under increased eccentric loading demands. Players with greater drop jump reactive strength index (RSI) demonstrated superior horizontal deceleration ability. Drop jump RSI had a greater association with the early compared to the late horizontal deceleration sub-phase. Of the drop jump kinetic variables examined, concentric mean force had the largest associations with horizontal deceleration ability. [ABSTRACT FROM AUTHOR]

Recent excavations of a modestly appointed house at the site of Morgantina in east-central Sicily recovered 175 loom weights or fragments thereof. In this study, we combine a detailed contextual analysis with new methodologies developed by the Center for Textile Research in Copenhagen in order to provide a comprehensive assessment of textile production in this house, the House of the Two Mills. Using these methods, we are able to identify the specific weights within the larger assemblage that most probably formed a single set, used together for weaving at this location. Moreover, the results of this analysis indicate that the loom weights that constituted this set would not have been produced and acquired all at once, but must have been accumulated by the household slowly over time. We propose that the most probable mechanism by which this slow process of accumulation played out would have been through household members passing down these textile tools as heirlooms across generations. We argue that in the process these weights would have been viewed by their users as having a value beyond their mere utilitarian function, instead becoming materializations of memory and the affective bonds formed in the intergenerational transfer of craft traditions. We conclude by considering the implications of this argument for the study of heirloom objects in archaeology and how a contextual understanding of broader Greek social institutions and practices can aid us in parsing peculiarities of the archaeological record. [ABSTRACT FROM AUTHOR]

A gold nanoparticles transparent electrode was realized by chemical reduction. This work aims to compare the transparent gold nanoparticles electrode with a more commonly utilized gold-film-coated electrode in order to investigate its potential use as counter-electrode (CE) in dye-sensitized solar cells (DSSCs). A series of DSSC devices, utilizing I−/I3− and Co(III)/(II) polypyridine redox mediators [Co(dtb)3]3+/2+; dtb = 4,4′ditert-butyl-2,2′-bipyridine)], were evaluated. The investigation focused firstly on the structural characterization of the deposited gold layers and then on the electrochemical study. The novelty of the work is the realization of a gold nanoparticles CE that reached 80% of average visible transmittance. We finally examined the performance of the transparent gold nanoparticles CE in DSSC devices. A maximum power conversion efficiency (PCE) of 4.56% was obtained with a commercial I−/I3−-based electrolyte, while a maximum 3.1% of PCE was obtained with the homemade Co-based electrolyte. [ABSTRACT FROM AUTHOR]

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Purpose: To examine relationships between methods of lower-limb stiffness and their associations with running economy (RE) and maximal velocity (vmax) in middle-distance (MD) runners. Methods: Eleven highly trained male MD runners performed a series of mechanical and physiological tests to determine maximal overground sprint speed, RE, and ...O2peak. Achilles tendon stiffness (kT) was estimated using ultrasonography during maximal isometric ankle plantar flexion. Global stiffness qualities were evaluated using a spring-mass model, providing measures of leg (kleg) and vertical stiffness (kvert) during running and jumping, respectively. Results: Very large (r = -.70) and large (r = -.60) negative relationships existed between RE and kT and kvert, during plantar flexion and unilateral jumps, respectively. There were large (r = .63) and extremely large (r = -.92) associations between kvert and kT and kleg during sprinting, respectively. Runners' vmax had large positive associations between kT (r = .52) and kleg (r = .59) during sprinting. Conclusions: In well-trained MD athletes, greater stiffness appears linked to faster and more economical running. Although kT had the strongest relationship with RE, kleg while sprinting and kvert in maximal unilateral jumps may be more practical measures of stiffness. Agreement between global stiffness assessments and kT highlights the energy contribution of the Achilles tendon to running efficiency and velocity. Further research incorporating these assessment tools could help establish more comprehensive mechanical and metabolic athlete profiles and further our understanding of training adaptations, especially stiffness modification, longitudinally. [ABSTRACT FROM AUTHOR]

Values of the fifth virial coefficient, compressibility factors, and fluid-fluid coexistence curves of binary asymmetric nonadditive mixtures of hard disks are reported. The former correspond to a wide range of size ratios and positive nonadditivities and have been obtained through a standard Monte Carlo method for the computation of the corresponding cluster integrals. The compressibility factors as functions of density, derived from canonical Monte Carlo simulations, have been obtained for two values of the size ratio (q = 0.4 and q = 0.5), a value of the nonadditivity parameter (Δ = 0.3), and five values of the mole fraction of the species with the biggest diameter (x1 = 0.1, 0.3, 0.5, 0.7, and 0.9). Some points of the coexistence line relative to the fluid-fluid phase transition for the same values of the size ratios and nonadditivity parameter have been obtained from Gibbs ensemble Monte Carlo simulations. A comparison is made between the numerical results and those that follow from some theoretical equations of state. [ABSTRACT FROM AUTHOR]

The emergence of supramolecular aggregates from simple microscopic interaction rules is a fascinating feature of complex fluids which, besides its fundamental interest, has potential applications in many areas, from biological self-assembly to smart material design. We here investigate by Monte Carlo simulation the equilibrium structure of a two-dimensional mixture of asymmetric dimers and spheres (disks). Dimers and disks are hard particles, with an additional short-range attraction between a disk and the smaller monomer of a dimer. The model parameters and thermodynamic conditions probed are typical of colloidal fluid mixtures. In spite of the minimalistic character of the interaction, we observe--upon varying the relative concentration and size of the two colloidal species--a rich inventory of mesoscale structures at low temperature, such as clusters, lamellæ (i.e., polymer-like chains), and gel-like networks. For colloidal species of similar size and near equimolar concentrations, a dilute fluid of clusters gives way to floating lamellæ upon cooling; at higher densities, the lamellæ percolate through the simulation box, giving rise to an extended network. A crystal-vapour phase-separation may occur for a mixture of dimers and much larger disks. Finally, when the fluid is brought in contact with a planar wall, further structures are obtained at the interface, from layers to branched patterns, depending on the nature of wall-particle interactions. [ABSTRACT FROM AUTHOR]

Graphene-based materials are among the most innovative and promising materials for the development of high-performance sensing devices, mainly due to the large surface area and the possibility to modify their reactivity by suitable functionalization. In the field of sensing applications, the peculiarities of innovative materials can be exploited only if chemical and physical properties are fully understood and correlated with each other. To this aim, in this work, graphene oxide (GO) and ethanol-treated GO (GOEt) were investigated from chemical and structural points of view. Electrical characterization was performed by depositing GO and GOEt between two electrodes by dielectrophoresis. All the investigations were repeated on GO materials after thermal treatment in a low temperature range (60 °C-300 °C). Furthermore, the electrical conductivity of GO was investigated by changing the temperature and the environment (air or N2) during the characterization: an increase in the conductivity of the as-deposited GO was observed when the device is cooled down and this effect is reversible with the temperature. GOEt and the thermally treated GO and GOEt show an opposite trend, confirming the key role of the oxygen functionalities in the conduction mechanisms and, therefore, in the conductivity of the GO layers. [ABSTRACT FROM AUTHOR]

The main aim of this study was to analyze the effect of resistance training programs differing in set configuration on mechanical force-velocity profiles. Thirteen participants performed 10 unilateral knee extension training sessions over 5 weeks. Each limb was randomized to one of the following set configurations: traditional (4 sets of 8 repetitions at maximum intended velocity, 10RM load, 3-min pause between sets) or interrepetition rest (32 maximum intended velocity repetitions, 10RM load, 17.4 s of rest between each repetition). Velocity of each repetition was recorded throughout the program. Before and after training, individual linear force velocities were calculated, and the following parameters were obtained: force and velocity axis intercept, slope, and estimated maximum power. Mean velocity was higher throughout the program for interrepetition rest configuration (0.54 ± 0.01 vs. 0.48 ± 0.01 m⋅s-1 for interrepetition rest, and traditional configuration respectively; main effect of set configuration: P < .001). There was a significant increase in force and velocity intercepts, but a steeper negative slope after both training protocols (main effect of time: P < .001 for every variable). Differences in resistance training velocity did not affect the adaptations. Our results suggest that, in a short-term program, maximum intended rather than actual velocity is a key factor to modulate strength adaptations. [ABSTRACT FROM AUTHOR]

Context: Eccentric exercises are increasingly being used to treat lower-limb musculoskeletal conditions such as Achilles tendinopathy. Despite widespread clinical application and documented efficacy, mechanisms underpinning clinical benefit remain unclear. Positive adaptations in motor performance are a potential mechanism. Objective: To investigate how an eccentric loading intervention influences measures of stretch-shortening-cycle (SSC) behavior during a hopping task. Design: Within-subjects repeated-measures observational study. Setting: University motion-analysis laboratory. Participants: Healthy adults. Interventions: A single intervention of 5 sets of 10 eccentric plantar-flexion contractions at 6 repetitions maximum using a commercial seated calf-raise machine. Main Outcome Measures: Lower-limb stiffness, sagittal-plane ankle kinematics, and temporal muscle activity of the agonist (soleus) and antagonist (tibialis anterior) muscles, measured during submaximal hopping on a custom-built sledge-jump system. Results: Eccentric loading altered ankle kinematics during submaximal hopping; peak angle shifted to a less dorsiflexed position by 2.9° and ankle angle precontact shifted by 4.4° (P < .001). Lower-limb stiffness increased from 5.9 to 6.8 N/m (P < .001), while surface EMG measures of soleus occurred 14--44% earlier (P < .001) after the loading intervention. Conclusions: These findings suggest that eccentric loading alters SSC behavior in a manner reflective of improved motor performance. Decreased ankle excursion, increased lower-limb stiffness, and alterations in motor control may represent a positive adaptive response to eccentric loading. These findings support the theory that mechanisms underpinning eccentric loading for tendinopathy may in part be due to improved "buffering" of the tendon by the neuromuscular system. [ABSTRACT FROM AUTHOR]

We investigate the structure of a dilute mixture of amphiphilic dimers and spherical particles, a model relevant to the problem of encapsulating globular "guest" molecules in a dispersion. Dimers and spheres are taken to be hard particles, with an additional attraction between spheres and the smaller monomers in a dimer. Using the Monte Carlo simulation, we document the low-temperature formation of aggregates of guests (clusters) held together by dimers, whose typical size and shape depend on the guest concentration X. For low X (less than 10%), most guests are isolated and coated with a layer of dimers. As X progressively increases, clusters grow in size becoming more and more elongated and polydisperse; after reaching a shallow maximum for X ≈50%, the size of clusters again reduces upon increasing X further. In one case only ( X = 50%and moderately low temperature) the mixture relaxed to a fluid of lamellae, suggesting that in this case clusters are metastable with respect to crystal-vapor separation. On heating, clusters shrink until eventually the system becomes homogeneous on all scales. On the other hand, as the mixture is made denser and denser at low temperature, clusters get increasingly larger until a percolating network is formed. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the reliability and validity of a simple computation method to evaluate force (F), velocity (v), and power (P) output during a countermovement jump (CMJ) suitable for use in field conditions and to verify the validity of this computation method to compute the CMJ force-velocity (F-v) profile (including unloaded and loaded jumps) in trained athletes. Methods: Sixteen high-level male sprinters and jumpers performed maximal CMJs under 6 different load conditions (0-87 kg). A force plate sampling at 1000 Hz was used to record vertical ground-reaction force and derive vertical-displacement data during CMJ trials. For each condition, mean F, v, and P of the push-off phase were determined from both force-plate data (reference method) and simple computation measures based on body mass, jump height (from flight time), and push-off distance and used to establish the linear F-v relationship for each individual. Results: Mean absolute bias values were 0.9% (± 1.6%), 4.7% (± 6.2%), 3.7% (± 4.8%), and 5% (± 6.8%) for F, v, P, and slope of the F-v relationship (SFv), respectively. Both methods showed high correlations for F-v-profile-related variables (r = .985-.991). Finally, all variables computed from the simple method showed high reliability, with ICC >.980 and CV <1.0%. Conclusions: These results suggest that the simple method presented here is valid and reliable for computing CMJ force, velocity, power, and F-v profiles in athletes and could be used in practice under field conditions when body mass, push-off distance, and jump height are known. [ABSTRACT FROM AUTHOR]

Squatting has received considerable attention in sports and is commonly utilized in daily activities. Knowledge of the squatting biomechanics in terms of its speed and depth may enhance exercise selection when targeting for sport-specific performance improvement and injury avoidance. Nonetheless, these perspectives have not been consistently reported. Hence, this preliminary study intends to quantify the kinematics, kinetics, and energetics in squat with different depths and speeds among healthy young adults with different physical activity levels; i.e., between active and sedentary groups. Twenty participants were administered to squat at varying depths (deep, normal, and half) and speeds (fast, normal, and slow). Motion-capture system and force plates were employed to acquire motion trajectories and ground reaction force. Joint moment was obtained via inverse dynamics, while power was derived as a product of moment and angular velocity. Higher speeds and deeper squats greatly influence higher joint moments and powers at the hip (p < 0. 0 5) and knee (p < 0. 0 5) than ankle, signifying these joints as the prime movers with knee as the predominant contributor. These preliminary findings show that the knee-strategy and hip-strategy were employed in compensating speed and depth manipulations during squatting. In certain contexts, appreciating these findings may provide clinically relevant implications, from the performance and injury avoidance viewpoint, which will ameliorate the physical activity level of practitioners. [ABSTRACT FROM AUTHOR]

Moderate rotation and moderate horizontal confinement similarly enhance the heat transport in Rayleigh-Bénard convection (RBC). Here, we systematically investigate how these two types of flow stabilization together affect the heat transport. We conduct direct numerical simulations of confined-rotating RBC in a cylindrical set-up at Prandtl number Pr = 4.38, and various Rayleigh numbers 2 × 108 < Ra < 7 × 109. Within the parameter space of rotation (given as inverse Rossby number 0 < Ro-1 < 40) and confinement (given as height-to-diameter aspect ratio 2 < Γ-1 < 32), we observe three heat transport maxima. At lower Ra, the combination of rotation and confinement can achieve larger heat transport than either rotation or confinement individually, whereas at higher Ra, confinement alone is most effective in enhancing the heat transport. Further, we identify two effects enhancing the heat transport: (i) the ratio of kinetic and thermal boundary layer thicknesses controlling the efficiency of Ekman pumping, and (ii) the formation of a stable domain-spanning flow for an efficient vertical transport of the heat through the bulk. Their interfering efficiencies generate the multiple heat transport maxima. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs) are classified into long and short events. Long GRBs (LGRBs) are associated with the end states of very massive stars, while short GRBs (SGRBs) are linked to the merger of compact objects. GRB 200826A was a peculiar event, because by definition it was an SGRB, with a rest-frame duration of ∼0.5 s. However, this event was energetic and soft, which is consistent with LGRBs. The relatively low redshift (z = 0.7486) motivated a comprehensive, multiwavelength follow-up campaign to characterize its host, search for a possible associated supernova (SN), and thus understand the origin of this burst. To this aim we obtained a combination of deep near-infrared (NIR) and optical imaging together with spectroscopy. Our analysis reveals an optical and NIR bump in the light curve whose luminosity and evolution are in agreement with several SNe associated to LGRBs. Analysis of the prompt GRB shows that this event follows the E p,iâ€" E iso relation found for LGRBs. The host galaxy is a low-mass star-forming galaxy, typical of LGRBs, but with one of the highest star formation rates, especially with respect to its mass ( log M * / M ⊙ = 8.6 , SFR ∼ 4.0 M ⊙ yrâˆ'1). We conclude that GRB 200826A is a typical collapsar event in the low tail of the duration distribution of LGRBs. These findings support theoretical predictions that events produced by collapsars can be as short as 0.5 s in the host frame and further confirm that duration alone is not an efficient discriminator for the progenitor class of a GRB. [ABSTRACT FROM AUTHOR]

Probabilistic methods are widely adopted for residual flood hazard assessment in flood‐prone areas protected by levees. Such methods can consider various sources of uncertainty, including breach location and flood event characteristics, and allow for the quantification of the result confidence. However, the possible occurrence of multiple levee breaches during the same flood event is usually disregarded. This paper presents a probabilistic method based on levee fragility functions and basic probability rules to estimate the probability of selected breach scenarios, including multiple breaching events. The flood hazard classification is based on inundation variables calculated for flood events of different return periods. A combined 1D‐2D hydrodynamic model is used for flood simulations. Probabilistic inundation extent maps and probabilistic flood hazard level maps are then created. Finally, probabilistic flood hazard estimates are summarized in a map of a suitable central tendency of the hazard level, coupled with a map of the Shannon entropy as an uncertainty indicator. This pair of statistical maps provides concise and effective information on a reference flood hazard along with the associated uncertainty. The method was applied to a region located along the middle reach of the Po River (northern Italy). Comparable central flood hazard estimates are obtained for the two sets of breaching events including or not including multiple breaches, with higher uncertainty if multiple breaches are considered. This result highlights the importance of considering multiple breaching events in flood risk management. Key Points: A probabilistic method is presented for flood hazard mapping in flood‐prone areas protected by levees, considering multiple breachesBreach scenario probabilities for selected return periods are estimated using levee fragility functions and basic probability rulesA "central" hazard level map and an entropy index map are introduced to summarize probabilistic information on flood hazard [ABSTRACT FROM AUTHOR]

Several anthropogenic products in wastewater are considered a threat to the aquatic environment. In addition to common industrial pollutants, levels of pharmaceuticals have been increasingly found in the environment in recent years, which may present a strong risk to the aquatic species that live there. The constant consumption of biologically active chemicals for human health has been matched by an increase in the leaking of these compounds in natural habitats over the last two decades. This study is aimed at evaluating the developmental toxicity of fotemustine in the ecological environment. Zebrafish embryos were exposed to doses of 25, 50 and 100 µg/mL from 4 h post-fertilization to 120 h. This study confirms that fotemustine exposure at 50 and 100 µg/mL affects the survival and hatching rate, morphology score and body length. Additionally, it significantly disturbs the antioxidant defense system and increases ROS in zebrafish larvae. From the molecular point of view, fotemustine exposure strongly induces apoptosis, endoplasmic reticulum stress (ERS) and the Wnt signaling pathway. [ABSTRACT FROM AUTHOR]

A space X is sequentially separable if there is a countable D ⊂ X such that every point of X is the limit of a sequence of points from D. Neither 'sequential + separable' nor 'sequentially separable' implies the other. Some examples of this are presented and some conditions under which one of the two implies the other are discussed. A selective version of sequential separability is also considered. [ABSTRACT FROM AUTHOR]

Purpose: The force–velocity relationship of muscular contraction has been extensively studied. However, previous research has focussed either on isolated muscle or single-joint movements, whereas human movement consists of multi-joint movements (e.g. squatting). Therefore, the purpose of this study was to investigate the force–velocity relationship of isovelocity squatting. Methods: Fifteen male participants (24 ± 2 years, 79.8 ± 9.1 kg, 177.5 ± 6 cm) performed isovelocity squats on a novel motorised isovelocity device (Kineo Training System) at three concentric (0.25, 0.5, and 0.75 m s−1) and three eccentric velocities (− 0.25, − 0.5, and − 0.75 m s−1). Peak vertical ground reaction forces, that occurred during the isovelocity phase, were collected using dual force plates (2000 Hz) (Kistler, Switzerland). Results: The group mean squat force–velocity profile conformed to the typical in vivo profile, with peak vertical ground reaction forces during eccentric squatting being 9.5 ± 19% greater than isometric (P = 0.037), and occurring between − 0.5 and − 0.75 m s−1. However, large inter-participant variability was identified (0.84–1.62 × isometric force), with some participants being unable to produce eccentric forces greater than isometric. Sub-group analyses could not identify differences between individuals who could/could not produce eccentric forces above isometric, although those who could not tended to be taller. Conclusions: These finding suggest that variability exists between participants in the ability to generate maximum eccentric forces during squatting, and the magnitude of eccentric increase above isometric cannot be predicted solely based on a concentric assessment. Therefore, an assessment of eccentric capabilities may be required prior to prescribing eccentric-specific resistance training. [ABSTRACT FROM AUTHOR]

In the last decade, the increasing number of devices connected to the internet has allowed the development of new technologies for distributed computing. IoT devices have reached computing capacities superior to personal computers of a few years ago, and their small size, low cost and lower energy consumption have made them fundamental for the new technological evolution. This paper analyzes and compares different solutions of serverless paradigms focused on dynamic behaviour adaptation, based on Function-as-a-Service (FaaS) framework. To allow a rapid interoperability of on-demand services, we propose a solution based on Blockchain, named BCB-FaaS, to ensure trustiness and accountability of function configuration, providing a strong barrier to well-known cyber-attacks. In addition, a cost analysis has been performed demonstrating how Blockchain can be an economic alternative to secure decentralized communications. [ABSTRACT FROM AUTHOR]

Assessment of the inter-limb asymmetry of leg stiffness is carried out using one-legged jumping tasks. However, the level of asymmetry may vary depending on the performance on one or both lower limbs. Therefore, the purpose of this study was to identify the differences in leg stiffness between the dominant and non-dominant lower limb during a two-legged countermovement jump. The research was conducted on 35 s-league basketball players (body height: 1.90 ± 0.08 m, body mass: 81.9 ± 10 kg, age: 19.5 ± 1.7 years). Each participant performed three countermovement jumps with arm swing to the maximum height. Measurements employed a BTS SMART motion analysis system and two Kistler force plates. Statistically significant differences were found during the comparison of leg stiffness in the dominant and non-dominant lower limbs. Inter-limb asymmetry of leg stiffness reached 22.0% in the countermovement phase and 8.9% in the take-off phase. Significant inter-limb asymmetry of leg stiffness might lead to injury or considerably reduce the performance of athletes. Therefore, an important role is to conduct strength and speed-strength trainings with proper loads to both body sides. Coaches should pay more attention to similar lower limbs movement patterns during two-legged exercises and bilateral strength development. [ABSTRACT FROM AUTHOR]

This numerical study presents a simple but extremely effective way to considerably enhance heat transport in turbulent wall-bounded multiphase flows, namely by using oleophilic walls. As a model system, we pick the Rayleigh-Bénard set-up, filled with an oil-water mixture. For oleophilic walls, using only 10%volume fraction of oil in water, we observe a remarkable heat transport enhancement of more than 100% as compared to the pure water case. In contrast, for oleophobic walls, the enhancement is only of about 20% as compared to pure water. The physical explanation of the heat transport increment for oleophilic walls is that thermal plumes detach from the oil-rich boundary layer and carry the heat with them. In the bulk, the oil-water interface prevents the plumes from mixing with the turbulent water bulk and to diffuse their heat. To confirm this physical picture, we show that the minimum amount of oil necessary to achieve the maximum heat transport is set by the volume fraction of the thermal plumes. Our findings provide guidelines of how to optimize heat transport in wall-bounded thermal turbulence. Moreover, the physical insight of how coherent structures are coupled with one of the phases of a two-phase system has very general applicability for controlling transport properties in other turbulent wall-bounded multiphase flows. [ABSTRACT FROM AUTHOR]

Due to a lack of observations and limited understanding of the complex mechanisms of tropical cyclone (TC) genesis, the possible TC activity response to future climate change remains controversial. In this work, a machine learning model, called the maximum entropy (MaxEnt) model, is established using various environmental variables. The model performs slightly better than the genesis potential index for historical TC activities based on the spatial correlation coefficient. Using coupled model intercomparison project phase 6 model projections, the MaxEnt model predicts a statistically significant decreasing trend of TC genesis probability under all shared socioeconomic pathway scenarios. In addition, our analysis reveals that TC genesis might have a complex nonlinear relationship with potential intensity, which is different from the positive relationship reported in previous studies and might be the key factor leading to the model predicting reduced TC genesis in the future. Plain Language Summary: Machine learning (ML) models show advantages in capturing the complex nonlinear relationship between predictors and predictands and can save much more computational costs than traditional climate models. The current work uses a maximum entropy (MaxEnt) ML model to predict tropical cyclone (TC) genesis, which shows better skills than some traditional methods. The MaxEnt model predicts a statistically significant decreasing TC genesis trend under all shared socioeconomic pathway scenarios. Compared to other variables, the potential intensity (PI) is the most important factor for the MaxEnt ML model. Furthermore, it reveals that, rather than a simple positive relationship, PI shows a complex nonlinear relationship with TC genesis, which is not noticed by previous studies. Key Points: A constructed various environmental variable‐based machine learning maximum entropy (MaxEnt) model performs well in predicting tropical cyclone genesisThe MaxEnt model predicts statistically significant decreasing tropical cyclone (TC) genesis trends in the future under all shared socioeconomic pathway scenariosThe most important environmental variable in the MaxEnt model is the potential intensity which shows a nonlinear relationship to TC genesis [ABSTRACT FROM AUTHOR]

This study aimed to determine the influence of footwear condition, foot-strike pattern and step frequency on running spatiotemporal parameters and lower-body stiffness during treadmill running. Thirty-one amateur endurance runners performed a two-session protocol (shod and barefoot). Each session consisted of two trials at 12 km · h−1 over 5 minutes altering step frequency every minute (150, 160, 170, 180 and 190 spm). First, participants were instructed to land with the heel first; after completion, the same protocol was repeated landing with the forefoot first. Repeated measures ANOVAs showed significant differences for footwear condition, foot-strike pattern and step frequency for each variable: percent contact time, percent flight time, vertical stiffness and leg stiffness (all p < 0.001). The results demonstrate greater estimated vertical and leg stiffness when running barefoot for both foot-strike patterns showing the largest values for barefoot+forefoot condition. Likewise, both vertical and leg stiffness became greater as step frequency increased. The proper manipulation of these variables facilitates our understanding of running performance and assist in training programmes design and injury management. [ABSTRACT FROM AUTHOR]

The identification of textile fibres from cultural property provides information about the object's technology. Today, microscopic examination remains the preferred method, and molecular spectroscopies (e.g. Fourier transform infrared (FTIR) and Raman spectroscopies) can complement it but may present some limitations. To avoid sampling, non-invasive fibre optics reflectance spectroscopy (FORS) in the near-infrared (NIR) range showed promising results for identifying textile fibres; but examining and interpreting numerous spectra with features that are not well defined is highly time-consuming. Multivariate classification techniques may overcome this problem and have already shown promising results for classifying textile fibres for the textile industry but have been seldom used in the heritage science field. In this work, we compare the performance of two classification techniques, principal component analysis–linear discrimination analysis (PCA-LDA) and soft independent modelling of class analogy (SIMCA), to identify cotton, wool, and silk fibres, and their mixtures in historical textiles using FORS in the NIR range (1000–1700 nm). We built our models analysing reference samples of single fibres and their mixtures, and after the model calculation and evaluation, we studied four historical textiles: three Persian carpets from the nineteenth and twentieth centuries and an Italian seventeenth-century tapestry. We cross-checked the results with Raman spectroscopy. The results highlight the advantages and disadvantages of both techniques for the non-invasive identification of the three fibre types in historical textiles and the influence their vicinity can have in the classification. [ABSTRACT FROM AUTHOR]

Bounded verification techniques such as bounded model checking (BMC) have successfully been used for many practical program analysis problems, but concurrency still poses a challenge. Here, we describe a new approach to BMC of sequentially consistent imperative programs that use POSIX threads. We first translate the multi-threaded program into a nondeterministic sequential program that preserves reachability for all round-robin scheduleswith a given bound on the number of rounds.We then reuse existing high-performance BMC tools as backends for the sequential verification problem. Our translation is carefully designed to introduce very small memory overheads and very few sources of nondeterminism, so it produces tight SAT/SMT formulae, and is thus very effective in practice: Our Lazy-CSeq tool implementing this translation for the C programming language won several gold and silver medals in the concurrency category of the Software Verification Competitions (SV-COMP) 2014-2021 andwas able to find errors in programswhere all other techniques (including testing) failed. In this article, we give a detailed description of our translation and prove its correctness, sketch its implementation using the CSeq framework, and report on a detailed evaluation and comparison of our approach. [ABSTRACT FROM AUTHOR]

This randomised controlled study examined the force–velocity relationship changes (force and velocity axis intercepts, slope and estimated maximum power) in response to 5-week training programmes differing in the set configuration. For each session, the traditional group performed 4 sets of 8 repetitions with 5 min of rest between sets and exercises, while the cluster group completed 16 sets of 2 repetitions with 1 min of rest between sets and 5 min between exercises. Both programmes were performed with the 10-repetition maximum load, including bench press, parallel squat, lat pull-down and leg curl exercises. Individual force-velocity profiles were obtained for bench press and squat using a linear velocity transducer before and after the intervention, along with lactate and mechanical performance during the intervention. Results showed in bench press similar changes of the force-velocity profile after both protocols (no shift of the slope and higher force and velocity axis intercept values). For the squat, significant changes in the slope (P = 0.001) and the velocity intercept (P = 0.002) towards a velocity profile were observed after cluster but not after traditional training. These results suggest that set configuration may modulate changes of force–velocity relationship, especially for squat. [ABSTRACT FROM AUTHOR]

Background: Thyroglobulin measurement in fine-needle aspiration (FNA-Tg) is an additional diagnostic tool of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC). However, its performance as a preoperative indicator of lateral neck LNM in PTC is unclear. We evaluated the use of FNA cytology and FNA-Tg to detect neck LNM presurgery using a simple methodology, and established a cut-off value for diagnosing LNM in PTC. Methods: We performed a retrospective cohort study based on hospital records, including 299 FNA-Tg measurements from 228 patients with PTC. The cut-off value for FNA-Tg was obtained through a receiver operating characteristic (ROC) curve analysis. The relationships between various parameters and FNA-Tg were analyzed using Spearman's correlation. Results: Of 299 lymph nodes (LNs) from 228 patients following surgery, 151 were malignant and 148 were benign. The median FNA-Tg levels were 414.40 ng/mL and 6.36 ng/mL in the metastatic and benign LNs, respectively. An FNA-Tg cut-off value of 28.3 ng/mL had the best diagnostic performance (93.38% sensitivity, 70.27% specificity, area under the ROC curve [AUC] 0.868) in the whole cohort. The diagnostic value performed better in the lateral neck group (level II–V, n = 163) than in the central neck group (level VI, n = 136); in the lateral neck group, the sensitivity and specificity of the FNA-Tg cut-off (16.8 ng/mL) were 96.25% and 96.36%, respectively. Conclusions: FNA-Tg is a useful technique for the diagnosis of LNM before surgery, especially in lateral neck dissection. Clinical trial registration number: ChiCTR1900028547. [ABSTRACT FROM AUTHOR]

In this paper an application of a non-equilibrium thermodynamic theory developed in previous papers for porous media filled by a fluid flow is given. A problem of propagation of coupled porosity and temperature waves is explored in a special case. For perfect isotropic media and in the one dimensional case the dispersion relation is worked out and three modes of propagation are derived. The diagrammes of the waves propagation speeds as functions of the wave number are represented for given values of some phenomenological coefficients present in the elaborated model. The carried out results have applications in several fields of science, as seismic waves, biology, medical sciences, nanotechnology and geology. [ABSTRACT FROM AUTHOR]

Study aim: This study compared movement velocity and force-velocity profile parameters measured by a free video analysis software program, with the use of a high-speed video recording, and a validated linear position transducer (LPT). Material and methods: Ten team-sports athletes performed double-leg and single-leg ballistic lower limb extensions on a leg press machine against a wide range of resistive loads. Each repetition was recorded by the LPT a high-speed camera (300 fps), and later analysed with a free video analysis software program. Results: Mean and peak movement velocity presented high reliability (ICC: 0.990 and 0.988, p < 0.001) and agreement between the two measuring systems (systematic bias: –0.06 ± 0.04 and –0.01 ± 0.03 m/s, respectively). Force-velocity profile parameters were also similar: maximum velocity at zero load (Vo: 1.79 ± 0.15 vs. 1.78 ± 0.12 m/s, p = 0.64), slope (b: –1585 ± 503 vs. –1562 ± 438 N · s/m, p = 0.43), maximum force at zero velocity (Fo: 2835 ± 937 vs. 2749 ± 694 N, p = 0.41) and maximum power (1274 ± 451 vs 1214 ± 285 W, p = 0.38). Both measuring systems could similarly detect the individual force or velocity deficit (p=0.91). Conclusion: In conclusion, a free video analysis software combined with a high-speed camera was shown to be a reliable, accurate, low bias and cost-effective method in velocity-based testing. [ABSTRACT FROM AUTHOR]

We study a pure fluid of heteronuclear sticky Janus dumbbells, considered to be the result of complete chemical association between unlike species in an initially equimolar mixture of hard spheres (species A) and sticky hard spheres (species B) with different diameters. The B spheres are particles whose attractive surface layer is infinitely thin. Wertheim's two-density integral equations are employed to describe the mixture of AB dumbbells together with unbound A and B monomers. After Baxter factorization, these equations are solved analytically within the associative Percus-Yevick approximation. The limit of complete association is taken at the end. The present paper extends to the more general, heteronuclear case of A and B species with size asymmetry a previous study by Wu and Chiew [J. Chem. Phys. 115, 6641 (2001)], which was restricted to dumbbells with equal monomer diameters. Furthermore, the solution for the Baxter factor correlation functions qijαβ(r) is determined here in a fully analytic way, since we have been able to find explicit analytic expressions for all the intervening parameters. [ABSTRACT FROM AUTHOR]