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We consider the problem of attaining either the maximal increase or reduction of the robustness of a complex network by means of a bounded modification of a subset of the edge weights. We propose two novel strategies combining Krylov subspace approximations with a greedy scheme and an interior point method employing either the Hessian or its approximation computed via the limited-memory Broyden-Fletcher-Goldfarb-Shanno algorithm (L-BFGS). The paper discusses the computational and modeling aspects of our methodology and illustrates the various optimization problems on networks that can be addressed within the proposed framework. Finally, in the numerical experiments we compare the performances of our algorithms with state-of-the-art techniques on synthetic and real-world networks. [ABSTRACT FROM AUTHOR]

Simple Summary: Contrary to other herbivores, in horses the forage:concentrate ratio of the diet may be critical according to the animal attitude and workload. In this study, diet digestibility and degradability (in vivo and in vitro, respectively) were assessed in five horses' diets that differed in the percentage of concentrates that, in adult horses, are considered more as a hay supplement rather than a basic feed. The determination of in vivo digestibility and in vitro degradability to assess the nutritional characteristics of the horses' diet shows how this approach can be of useful to determine concentrate intake and optimize the energy content in a horse's diet. Determination of digestibility represents the first step for the evaluation of the net energy content of feed for livestock animals. The aim of this study was to evaluate the in vivo digestibility and in vitro degradability of five diets characterized by different forage/concentrate ratios (F:C) in horses. The in vitro degradability was determined by the Gas Production Technique (GPT), using as an inoculum source the feces of the same subjects used for the in vivo test. Five diets consisting of poliphyte hay, straw and grains of barley and oats with a different F:C ratio [90/10 (Diet 1); 78/22 (Diet 2); 68/32 (Diet 3); 60/40 (Diet 4); 50/50 (Diet 5) were formulated and administered in succession, starting with Diet 1. In the in vivo results, no significant differences emerged, despite the different F:C content. In in vitro fermentation, four diets out of the five (2, 3, 4, 5) presented a similar trend of the curve of gas production, showing good activity of the fecal micro population during the first hours of incubation. An important correlation between gas and Volatile Fatty Acid (VFA) were found, suggesting that the processes linked to the micro population deriving from the horse's caecum follow metabolic pathways whose products can be modeled in the same way as for the rumen. The GPT could represent the correct method for studying the nutritional characteristics of feed for horses, using feces as the source of inoculum, even if further investigations must be performed to improve the technique. [ABSTRACT FROM AUTHOR]

We present a unifying Perron--Frobenius theory for nonlinear spectral problems defined in terms of nonnegative tensors. By using the concept of tensor shape partition, our results include, as a special case, a wide variety of particular tensor spectral problems considered in the literature and can be applied to a broad set of problems involving tensors (and matrices), including the computation of operator norms, graph and hypergraph matching in computer vision, hypergraph spectral theory, higher-order network analysis, and multimarginal optimal transport. The key to our approach is to recast the eigenvalue problem as a fixed point problem on a suitable product of projective spaces. This allows us to use the theory of multihomogeneous order-preserving maps to derive new and unifying Perron--Frobenius theorems for nonnegative tensors, which either imply earlier results of this kind or improve them, as weaker assumptions are required. We introduce a general power method for the computation of the dominant tensor eigenpair and provide a detailed convergence analysis. [ABSTRACT FROM AUTHOR]

Context: Pasture is widely used in rural Mediterranean areas as a local resource for animal feeding in a sustainable food system. Aims: The present study aimed at evaluating the effects of pasture from a Mediterranean environment on milk fatty acid profile and organoleptic characteristics in grazing Cilentana goats bred in Cilento (Salerno province, southern Italy). Methods: Twelve Cilentana dairy goats, grazing on local feeding resources were studied for 5 months (from May to September), starting from 60 days after kidding. Bodyweight and milk yield were recorded, whereas milk samples were collected and analysed for milk chemical composition and fatty acid profile. Milk organoleptic characteristics were analysed using an instrumental sensory platform. Key results: Season significantly (P < 0.01) affected the pasture fatty acid profile, with the highest polyunsaturated fatty acid (PUFA) content (64.83%) occurring in May. Results of the milk fatty acid composition, permitted to classify as 'High quality' the goat milks sampled in May and June, with the significantly (P < 0.01) highest monounsaturated fatty acid (MUFA; 23.98% and 25.37%) and PUFA (4.74% and 4.43%) contents and lowest saturated fatty acid:unsaturated fatty acid (SFA:UFA) ratio (2.50 and 2.36), and as 'Low quality' those sampled in August and September with the significantly (P < 0.01) highest SFA (75.79% and 75.84%) content. Milk n -6: n -3 polyunsaturated fatty acid ratio was always lower than 4. Some sensory differences in milk organoleptic characteristics were detected by the artificial senses platform, which would be almost impossible to detect by a human panel. Conclusions: Milk samples obtained from grazing goats were influenced by the quality of local feeding resources in terms of nutraceutical value and sensory profile. Implications: Pasture influenced the composition of milk functional compounds, improving the UFAs and conjugated linoleic acid isomers, widely recognised as having beneficial effects on human health. The n -6: n -3 PUFA ratio, lower than 4, confirms the positive effects of pasture on nutritional characteristics of goat milk and underlines the important role of pasture of marginal areas for the quality of livestock products in the frame of a sustainable agro-food system. Some differences were detected by the artificial senses platform among milk samples, which were almost impossible to detect by a human panel, highlighting the potentiality of the artificial senses to link animal-sourced foods to a territory. Pasture is widely used in Mediterranean areas as local resource for animal feeding, guaranteeing favourable chemical and sensory characteristics of products. The aim of the study was to assess milk chemical and sensory characteristics of 12 Cilentana goats grazing in a mountainous area of Cilento (southern Italy). Positive effects of pasture on nutritional characteristics of goat milk underline the important role of pasture of marginal areas for the quality of livestock products in the frame of a sustainable agro-food system. [ABSTRACT FROM AUTHOR]

Background: Aggressive surgical resection in locally advanced hepatopancreatobiliary (HPB) malignancies is frequently advocated as the only potentially curative treatment. In recent years, advances in chemotherapy regimens and surgical techniques have led to improved oncologic outcomes and overall survival, by increasing the rates of radical (R0) resections. Vascular resections are increasingly reported to further increase disease clearance rates. Within this perspective, the issue of vascular reconstruction has raised growing interest, drawing particular attention to vascular substitutes and surgical techniques for reconstruction. Case presentation: A case of extrahepatic cholangiocarcinoma with high clinical suspicion of vascular infiltration of the portal trunk at preoperative assessment is reported. An autologous interposition graft, harvested from diaphragmatic peritoneum, was chosen as a vascular substitute leading to successful portal trunk reconstruction and overcoming all possible drawbacks associated with cadaveric and artificial grafts reconstructions. Conclusion: This solution was strategic to ensure complete oncologic clearance averting the risk of positive margins (R1) at final pathology. [ABSTRACT FROM AUTHOR]

Osteochondritis dissecans of the knee (OCD) is a multifactorial pathology in where repetitive microtrauma plays a central role in the etiopathogenesis. Knee MRI is indicated in young, active patients who have knee pain and/or effusion, to make an early diagnosis and decide about treatment, according essentially to the MRI stability signs. The choice of treatment should be also tailored, based on the patient's skeletal maturity, as well as the size and location of the lesion. Conservative treatment with restricting sports activities is the first line treatment and often sufficient to ensure healing in patients with open physes. Surgical treatment depends on the persistence of symptoms after 6 months of conservative treatment and/or based on the development of signs of instability of the lesion. Stable lesions with intact articular cartilage may be treated by drilling of the subchondral bone aiming to stimulate vascular ingrowth and subchondral bone healing. Every attempt should be made to retain the osteochondral fragment when possible. Instable lesions should be fixed or "replaced" with salvage procedures to prevent the onset of early osteoarthritis in this young population. Furthers studies are needed to improve the knowledge and optimizing non-operative and surgical treatment and to develop noninvasive diagnostic tools to predict with more accuracy the fragment's stability. [ABSTRACT FROM AUTHOR]

Simple Summary: Ovarian hormones are involved in ovarian cancer pathogenesis. However, few reports have investigated the hormone receptor pattern according to BRCA mutational status. The aim of this single-center, observational, retrospective study was to explore the relationship between hormone receptor status and BRCA1/2 mutation in a cohort of 207 high-grade serous ovarian carcinoma (HGSOC) patients. Interesting differences emerged between BRCA-mutated and BRCA wild-type women, in terms of pattern of receptor expression and its association to the outcome. On the whole, our findings, though needing further validation, extend our understanding of the complex interplay between BRCA1/2 protein and hormone signaling, suggesting new pathways to be exploited in order to develop future personalized therapy. Several studies have explored the prognostic role of hormone receptor status in high-grade serous ovarian cancer (HGSOC) patients. However, few reports have investigated their expression according to BRCA mutational status. The aim of this single-center, observational, retrospective study was to explore the hormone receptor pattern and its potential prognostic role in a cohort of 207 HGSOC women stratified for BRCA mutational status. To this end, ERα, ERβ1, ERβ2, ERβ5, PR, and AR expression were assessed by immunohistochemistry in 135 BRCA-wild type (BRCA-wt) and 72 BRCA1/2 mutation carriers (BRCA-mut). No significant difference emerged in hormone receptor expression between the two sub-samples, except for a significantly lower ERα expression observed in pre-menopausal BRCA1/2-mut as compared to BRCA-wt patients (p = 0.02). None of the examined hormone receptors has revealed a significant prognostic role in the whole sample, apart from the ratio ERα/ERβ5 nuclear, for which higher values disclosed a positive role on the outcome in BRCA-wt subgroup (HR 0.77; CI 0.61–0.96; p = 0.019). Conversely, it negatively affected overall survival in the presence of BRCA1/2-mut (HR 1.41; CI 1.06–1.87; p = 0.020). Finally, higher PR levels were associated with platinum sensitivity in the whole sample (p = 0.019). Our data, though needing further validation, suggest a potential role of oestrogen-mediated pathways in BRCA1/2-associated HGSOC tumorigenesis, thus revealing a possible therapeutic potential for targeting this interaction. [ABSTRACT FROM AUTHOR]

This article focuses on the role that National Human Rights Institutions play in guaranteeing access to justice for national minorities. Based on the OSCE HCNM Graz Recommendations on Access to Justice and National Minorities, this study aims at identifying commons issues and good practices by comparing rules and practices concerning minority representation in NHRIs, NHRIs' focus on national minority issues, and NHRIs' role in providing access to justice for national minorities. Separate subsections cover collective-groups' complaints and the relevance of groups during investigations; regional offices; and websites, languages, and online complaints. The conclusion highlights that protecting access to justice for national minorities entails both more 'focus' and 'access'. More focus should be guaranteed by relevant legislation and NHRIs' annual reports through separate chapters or sections on minorities. More access includes minority representation in NHRIs, regional offices, groups' complaints, multilingual and easy-to-access websites, as well as online tools for complaints. [ABSTRACT FROM AUTHOR]

This paper reports the main results of an experimental study on the mechanics of intensely fissured natural clays, extending our previous studies on scaly clay from Santa Croce di Magliano. While previous work focused on the influence of the orientation of fissures with respect to the loading direction, the present investigation specifically explores an additional, important variable: the stress level. The combined effect of fissure orientation and confining pressure was studied by setting up a large campaign of plane strain compression experiments, in which different combinations of these two variables were tested. Conventional global stress–strain measurements were complemented by measuring displacement and strain fields through two-dimensional digital image correlation. Such rich information provided a clear and consistent picture of the interplay between fissure orientation and stress level and revealed complex deformation patterns, which cannot be ignored for a proper interpretation of the material response. [ABSTRACT FROM AUTHOR]

Background: The influence of pregnancy on long-term disability in multiple sclerosis (MS) is still controversial. Objective: To assess the risk of long-term disability worsening after pregnancy in MS women as compared with a propensity-score (PS) matched group of MS women without pregnancy. Methods: In the setting of the Italian Pregnancy Dataset, MS patients with (pregnancy group (PG)) and without pregnancy (control group (CG)) were recruited. Time to disability worsening on the Expanded Disability Status Scale (EDSS) was assessed through a multivariable Cox regression model. Results: The PS-matching retained 230 PG and 102 CG patients. After a follow-up of 6.5 +/- 3.1 years, disability worsening occurred in 87 (26.2%) women. In the multivariable analysis, disability worsening was associated with pregnancy in women with relapses in the year before conception (adjusted hazard ratio (aHR) = 1.74; 95% confidence interval (CI) 1.06–2.84; p = 0.027), higher EDSS (aHR = 1.39; 95% CI 1.12–1.74; p = 0.003), younger age (aHR = 0.95; 95% CI 0.91–0.99; p = 0.022) and shorter DMD exposure over the follow-up (p < 0.008). Conclusion: Pregnancy in MS women with relapses in the year before conception increases the risk of long-term disability worsening. Our findings underscore the importance of counselling in MS women facing a pregnancy that should be planned after a period of clinical stability, favouring treatment optimization in patients with recent disease activity. [ABSTRACT FROM AUTHOR]

This paper presents results from numerical simulations of a non-premixed hydrogen-air rotating detonation combustor with radial injection. The fuel and air mass flow rate are varied in order to hold a unity global equivalence ratio. The calculations show that multiple detonation waves co-exist when the mass flow rate is increased. Conditional statistics of the detonation structure and combustion processes suggest similarities across co-existing waves. Quantification of the injection response to the rotation of a detonation indicates that at higher flow rate the refill time is short enough to allow for a quick and well mixed composition prior to the new front passage. Details of the combustion characteristics are analyzed. The results elucidate the correlation between initial injection conditions and detonation multiplicity on the overall physics within the combustor. [Display omitted] • Detailed three-dimensional simulations of rotating detonation engine are performed. • Increasing mass flow rate improves fuel-oxidizer mixing and injection response. • Co-existing detonation waves have self-similar structures. • Combustion performance under co-existing detonation waves is explored. • Initial injection conditions dictate the number of detonation waves. [ABSTRACT FROM AUTHOR]

Network scientists have shown that there is great value in studying pairwise interactions between components in a system. From a linear algebra point of view, this involves defining and evaluating functions of the associated adjacency matrix. Recent work indicates that there are further benefits from accounting directly for higher order interactions, notably through a hypergraph representation where an edge may involve multiple nodes. Building on these ideas, we motivate, define and analyze a class of spectral centrality measures for identifying important nodes and hyperedges in hypergraphs, generalizing existing network science concepts. By exploiting the latest developments in nonlinear Perron−Frobenius theory, we show how the resulting constrained nonlinear eigenvalue problems have unique solutions that can be computed efficiently via a nonlinear power method iteration. We illustrate the measures on realistic data sets. Evaluating the importance of nodes and hyperedges in hypergraphs is relevant to link detection, link prediction and matrix completion. Here, the authors define a family of nonlinear eigenvector centrality measures for both edges and nodes in hypergraphs, propose an algorithm to calculate them, and illustrate their application on real-world data sets. [ABSTRACT FROM AUTHOR]

Network scientists have shown that there is great value in studying pairwise interactions between components in a system. From a linear algebra point of view, this involves defining and evaluating functions of the associated adjacency matrix. Recent work indicates that there are further benefits from accounting directly for higher order interactions, notably through a hypergraph representation where an edge may involve multiple nodes. Building on these ideas, we motivate, define and analyze a class of spectral centrality measures for identifying important nodes and hyperedges in hypergraphs, generalizing existing network science concepts. By exploiting the latest developments in nonlinear Perron−Frobenius theory, we show how the resulting constrained nonlinear eigenvalue problems have unique solutions that can be computed efficiently via a nonlinear power method iteration. We illustrate the measures on realistic data sets. Evaluating the importance of nodes and hyperedges in hypergraphs is relevant to link detection, link prediction and matrix completion. Here, the authors define a family of nonlinear eigenvector centrality measures for both edges and nodes in hypergraphs, propose an algorithm to calculate them, and illustrate their application on real-world data sets. [ABSTRACT FROM AUTHOR]

Core–periphery detection aims to separate the nodes of a complex network into two subsets: a core that is densely connected to the entire network and a periphery that is densely connected to the core but sparsely connected internally. The definition of core–periphery structure in multiplex networks that record different types of interactions between the same set of nodes on different layers is non-trivial since a node may belong to the core in some layers and to the periphery in others. We propose a nonlinear spectral method for multiplex networks that simultaneously optimizes a node and a layer coreness vector by maximizing a suitable non-convex homogeneous objective function by a provably convergent alternating fixed-point iteration. We derive a quantitative measure for the quality of a given multiplex core–periphery structure that allows the determination of the optimal core size. Numerical experiments on synthetic and real-world networks illustrate that our approach is robust against noisy layers and significantly outperforms baseline methods while improving the latter with our novel optimized layer coreness weights. As the runtime of our method depends linearly on the number of edges of the network, it is scalable to large-scale multiplex networks. [ABSTRACT FROM AUTHOR]

In this work, the relevance of the multi-phase thermodynamic model based on the vapor–liquid equilibrium (VLE) assumption over the single-phase model is discussed. An emphasis on the importance of the non-linear coupling between thermodynamic, transport, and governing equations is given from a macroscopic point of view by analyzing the mixing effects on a spatial mixing layer in real-gas (non-ideal) conditions. The goal is to prove the existence of an important difference between the two thermodynamic models and, therefore, establish the foundations on the effects that VLE induces in a fluid flow. The results indicate that differences in micro-mixing, ultimately changing the vortex dynamics, are directly related to the imbalance between the heat and mass transfer that occurs within the VLE mixing region of a shear layer. [ABSTRACT FROM AUTHOR]

In this work, multiferroic bismuth ferrite (BFO) was functionalized with meso-tetraphenylporphine-4,4′,4′′,4′′′-tetracarboxylic acid (TCPP). This new hybrid organic–inorganic material shows an enhanced photocatalytic activity for the degradation of organic dyes as it combines the properties of BFO which is an efficient visible light photocatalyst with peculiar porphyrin absorption in visible light. The anchoring of TCPP to the OH-terminations of the BFO surface through its carboxylic tethering groups was demonstrated using X-ray photoelectron spectroscopy and FT-IR spectroscopy. The photocatalytic activity of the material was also demonstrated through the photocatalytic degradation of Methylene Blue (MB) and Rhodamine-B (Rhd-B) in water under simulated solar light illumination. The TCPP molecules anchored to BFO slightly decrease (∼0.06 eV) the bandgap energy of the system and act as new catalytic centres, thus improving its photocatalytic activity. A photodegradation mechanism was also proposed. This new material is reusable and stable, as it maintains an unmodified photo-activity after several MB discoloration runs. [ABSTRACT FROM AUTHOR]

• PROTO-SPHERA is a new concept of spherical torus with closed flux surfaces and a force-free Screw Pinch with open flux surfaces. • A two colour interferometer is the diagnostic system to measure the line density and to characterize this uncommon plasma. • For the high densities and its rate variation which can provoke a beam refraction a CO2 laser is the wavelength choice. • A two-colour vibration compensation system is foreseen by using a He-Ne laser. • The interferometer was assembled in a laboratory, a test interferometric signal has been observed. PROTO-SPHERA (Spherical Plasma for Helicity Relaxation Assessment) is a new concept of torus that aims to produce a spherical torus with closed flux surfaces and a force-free Screw Pinch with open flux surfaces, fed by electrodes. In order to verify the stability of the configuration and the technical components of the PROTO-SPHERA initial arc, the initial Phase-1 experiment was built, and its plasma, in the year 2108, has reached both the total current (10 kA) and total duration (1 s) targets. A two colour interferometer is one of the diagnostic system proposed to provide PROTO-SPHERA with the measurement of its electron density, which is currently of the order of ∼1020 m−3. It will allow to obtain line density, necessary to characterize this uncommon plasma, as integrate measurement along the equatorial plane. The design and the interferometer characteristics are described in this paper. [ABSTRACT FROM AUTHOR]

We introduce the concept of shape partition of a tensor and formulate a general tensor eigenvalue problem that includes all previously studied eigenvalue problems as special cases. We formulate irreducibility and symmetry properties of a nonnegative tensor T in terms of the associated shape partition. We recast the eigenvalue problem for T as a fixed point problem on a suitable product of projective spaces. This allows us to use the theory of multihomogeneous orderpreserving maps to derive a new and unifying Perron{Frobenius theorem for nonnegative tensors which either implies earlier results of this kind or improves them, as weaker assumptions are required. We introduce a general power method for the computation of the dominant tensor eigenpair and provide a detailed convergence analysis. [ABSTRACT FROM AUTHOR]

The Perron--Frobenius theory for nonnegative matrices has been generalized to orderpreserving homogeneous mappings on a cone and more recently to nonnegative multilinear forms. We unify both approaches by introducing the concept of order-preserving multihomogeneous mappings, their associated nonlinear spectral problems, and spectral radii. We show several Perron--Frobenius type results for these mappings addressing existence, uniqueness, and maximality of nonnegative and positive eigenpairs. We prove a Collatz--Wielandt principle and other characterizations of the spectral radius and analyze the convergence of iterates of these mappings toward their unique positive eigenvectors. On top of providing a new extension of the nonlinear Perron--Frobenius theory to the multidimensional case, our contribution poses the basis for several improvements and a deeper understanding of the current spectral theory for nonnegative tensors. In fact, in recent years, important results have been obtained by recasting certain spectral equations for multilinear forms in terms of homogeneous maps; however, as our approach is more adapted to such problems, these results can be further refined and improved by employing our new multihomogeneous setting. [ABSTRACT FROM AUTHOR]

High‐speed neutron tomographies (1‐min acquisition) have been acquired during water invasion into air‐filled samples of both intact and deformed (ex situ) Vosges sandstone. Three‐dimensional volume images have been processed to detect and track the evolution of the waterfront and to calculate full‐field measurement of its speed of advance. The flow process correlates well with known rock properties and is especially sensitive to the distribution of the altered properties associated with observed localized deformation, which is independently characterized by Digital Volume Correlation of X‐ray tomographies acquired before and after the mechanical test. The successful results presented herein open the possibility of in situ analysis of the local evolution of hydraulic properties of rocks due to mechanical deformation. Key Points: Full 3‐D fluid front velocity map can be obtained from high‐speed (1 min per tomography) neutron tomography during water invasion into dry samplesQuantitative measurements are validated by comparing experimental results to 1‐D analytical solution of pressure‐driven flowDuring imbibition, compactant shear bands result in locally higher fluid flow velocity due to decreased pore size in the bands [ABSTRACT FROM AUTHOR]

Identifying important components in a network is one of the major goals of network analysis. Popular and effective measures of importance of a node or a set of nodes are defined in terms of suitable entries of functions of matrices f(A). These kinds of measures are particularly relevant as they are able to capture the global structure of connections involving a node. However, computing the entries of f(A) requires a significant computational effort. In this work we address the problem of estimating the changes in the entries of f(A) with respect to changes in the edge structure. Intuition suggests that, if the topology, or the overall weight, of the connections in the new graph G is not significantly distorted, relevant components in $G$ maintain their leading role in G. We propose several bounds giving mathematical reasoning to such intuition and showing, in particular, that the magnitude of the variation of the entry f(A)kl decays exponentially with the shortest-path distance in $G$ that separates either k or l from the set of nodes touched by the edges that are perturbed. Moreover, we propose a simple method that exploits the computation of f(A) to simultaneously compute the all-pairs shortest-path distances of G, with essentially no additional cost. The proposed bounds are particularly relevant when the nodes whose edge connection tends to change more often or tends to be more often affected by noise have a marginal role in the graph and are distant from the most central nodes. [ABSTRACT FROM AUTHOR]

Dynamical systems on hypergraphs can display a rich set of behaviors not observable for systems with pairwise interactions. Given a distributed dynamical system with a putative hypergraph structure, an interesting question is thus how much of this hypergraph structure is actually necessary to faithfully replicate the observed dynamical behavior. To answer this question, we propose a method to determine the minimum order of a hypergraph necessary to approximate the corresponding dynamics accurately. Specifically, we develop a mathematical framework that allows us to determine this order when the type of dynamics is known. We use these ideas in conjunction with a hypergraph neural network to directly learn the dynamics itself and the resulting order of the hypergraph from both synthetic and real datasets consisting of observed system trajectories. [ABSTRACT FROM AUTHOR]

Revealing a community structure in a network or dataset is a central problem arising in many scientific areas. The modularity function Q is an established measure quantifying the quality of a community, being identified as a set of nodes having high modularity. In our terminology, a set of nodes with positive modularity is called a module and a set that maximizes Q is thus called a leading module. Finding a leading module in a network is an important task; however, the dimension of real-world problems makes the maximization of Q unfeasible. This poses the need of approximation techniques which are typically based on a linear relaxation of Q, induced by the spectrum of the modularity matrix M. In this work we propose a nonlinear relaxation which is instead based on the spectrum of a nonlinear modularity operator M. We show that extremal eigenvalues of M provide an exact relaxation of the modularity measure Q, in the sense that the maximum eigenvalue of M is equal to the maximum value of Q, although at the price of being more challenging to be computed than those of M. Thus we extend the work made on nonlinear Laplacians by proposing a computational scheme, named generalized RatioDCA, to address such extremal eigenvalues. We show monotonic ascent and convergence of the method. We finally apply the new method to several synthetic and real-world datasets, showing both effectiveness of the model and performance of the method. [ABSTRACT FROM AUTHOR]

In a graph or complex network, communities and anti-communities are node sets whose modularity attains extremely large values, positive and negative, respectively. We consider the simultaneous detection of communities and anti-communities, by looking at spectral methods based on various matrix-based definitions of the modularity of a vertex set. Invariant subspaces associated to extreme eigenvalues of these matrices provide indications on the presence of both kinds of modular structure in the network. The localization of the relevant invariant subspaces can be estimated by looking at particular matrix angles based on Frobenius inner products. [ABSTRACT FROM AUTHOR]

Hypergraph matching has recently become a popular approach for solving correspondence problems in computer vision as it allows the use of higher-order geometric information. Hypergraph matching can be formulated as a third-order optimization problem subject to assignment constraints which turns out to be NP-hard. In recent work, we have proposed an algorithm for hypergraph matching which first lifts the third-order problem to a fourth-order problem and then solves the fourth-order problem via optimization of the corresponding multilinear form. This leads to a tensor block coordinate ascent scheme which has the guarantee of providing monotonic ascent in the original matching score function and leads to state-of-the-art performance both in terms of achieved matching score and accuracy. In this paper we show that the lifting step to a fourth-order problem can be avoided yielding a third-order scheme with the same guarantees and performance but being two times faster. Moreover, we introduce a homotopy type method which further improves the performance. [ABSTRACT FROM AUTHOR]

Introduction. Although intra-articular injections of hyaluronic acid (HA) are common non-operative measures used in clinical practice in the management of symptomatic osteoarthritis, there is a great controversy on their efficacy and safety compared to corticosteroids (CSs). Efficacy. Conflicting results have been reported in clinical trials and meta-analysis due to methodological differences in study design, along with collection, analysis, and interpretation of data. Even if some studies reported small or no differences of HA compared with CSs (or inferred that HA is not more effective than saline as a placebo), in general CSs have shown to be superior in the short term (especially on pain control), while better results have been reported with HA at subsequent evaluations, but with only a moderate effect after 26 weeks. Safety. Mild or moderate adverse events have generally been reported after HA injections, the most common being injection site pain. HA is generally considered safe compared to CSs or saline. Furthermore, HA has shown to be safe also after a previous course of injections. Conclusions. Conflicting results have been reported on the efficacy and safety of HA. Guidelines are controversial and in most of the cases “uncertain” recommendations are provided due to inconclusive evidence in literature. However, HA does not seem to have significantly higher side effects when compared to saline or CSs injections, and provides better medium-term control of symptoms in patients with mild to moderate knee osteoarthritis. [ABSTRACT FROM AUTHOR]

Posttraumatic neglected Achilles tendon ruptures in a young patient have not been described in the literature to our knowledge; indeed, neglected ruptures of the Achilles tendon have only rarely been described in adults. We present the case of a 7 year old girl with posttraumatic neglected rupture of the Achilles tendon that was operated on 8 weeks after the trauma. [ABSTRACT FROM AUTHOR]

Various modularity matrices appeared in the recent literature on network analysis and algebraic graph theory. Their purpose is to allow writing as quadratic forms certain combinatorial functions appearing in the framework of graph clustering problems. In this paper we put in evidence certain common traits of various modularity matrices and shed light on their spectral properties that are at the basis of various theoretical results and practical spectral-type algorithms for community detection. [ABSTRACT FROM AUTHOR]

We prove that the Bernoulli numbers satisfy some special lower triangular Toeplitz systems of linear equations. One of these systems has a strong link with eleven Ramanujan's linear equations satisfied by the first eleven Bernoulli numbers. [ABSTRACT FROM AUTHOR]

Tracking the dynamic morphology of active materials during operation of lithium batteries is essential for identifying causes of performance loss. Digital volume correlation (DVC) is applied to high‐speed operando synchrotron X‐ray computed tomography of a commercial Li/MnO2 primary battery during discharge. Real‐time electrode material displacement is captured in 3D allowing degradation mechanisms such as delamination of the electrode from the current collector and electrode crack formation to be identified. Continuum DVC of consecutive images during discharge is used to quantify local displacements and strains in 3D throughout discharge, facilitating tracking of the progression of swelling due to lithiation within the electrode material in a commercial, spiral‐wound battery during normal operation. Displacement of the rigid current collector and cell materials contribute to severe electrode detachment and crack formation during discharge, which is monitored by a separate DVC approach. Use of time‐lapse X‐ray computed tomography coupled with DVC is thus demonstrated as an effective diagnostic technique to identify causes of performance loss within commercial lithium batteries; this novel approach is expected to guide the development of more effective commercial cell designs. [ABSTRACT FROM AUTHOR]

Aim of this study was to investigate the effects of supplementing dairy goat diets with hydrogenated palm oil (HPO; 50 g/day/head) on milk yield and composition, and on milk fatty acids profile and Stearoyl-CoA desaturase gene expression. Compared with the control diet (C), supplementation with HPO increased milk yield and fat percentage. By contrast, milk protein percentage was not different between groups. Supplementation with HPO increased ( P < 0.01) short and medium chain fatty acids, as well as C14:0 and C16:1 cis-9 acids ( P < 0.05). Milk from control group showed significantly ( P < 0.01) higher concentration of C18:0 and lower ( P < 0.05) of cis-9 trans-11CLA. Concerning the desaturase index, the HPO addition significantly affected C16:1/C16:0 and cis-9 trans-11CLA/C18:1 trans-11 ( P < 0.01) and C18:1/C18:0 ( P < 0.05) ratios. The SCD gene expression (arbitrary units) was higher, even if not significantly, in the control compared to the treated group and in both groups decreased along the trial (May: 0.55 vs 0.41; June: 0.51 vs 0.38; July: 0.50 vs 0.37 for C and T group, respectively). Concerning health properties of milk, showing beneficial (CLAs and palmitoleic acid increase) and adverse (myristic acid increase) effect, our results suggest that further studies are needed to address a risk/benefit assessment of HPO supplementation in goats. [ABSTRACT FROM AUTHOR]

Background: a wrong position of bone tunnels, in particular on the femur, is one of the most frequent causes of a failed anterior cruciate ligament (ACL) reconstruct ion. Several studies demonstrated that drilling the femoral tunnel through the antero-medial portal (AMP) allows a more anatomical placement on the lateral femoral condyle and higher knee stability, compared to trans-tibial (TT) technique. The aim of this study was to retrospectively evaluate two groups of soccer players operated on for ACL reconstruction according to either one of these two techniques. Methods: two groups of non-professional soccer players operated on for a single bundle ACL reconstruction with hamstrings autograft using either a TT (20 patients) or an AMP (23 patients) technique were retrospectively evaluated with KT- 1000 arthrometer, manual pivot shift test, isokinetic test, the incremental treadmill-running test, athletic and sport specific tasks, and knee scores (IKDC, Lysholm and KOOS). Results: the AMP group showed better results at pivot shift test and KOOS, but lower flexion angles at single leg squat test. There were no differences in all the other considered outcomes. Conclusions: the better rotational stability of the knee achieved in AMP group did not lead to significantly better clinical and functional results in our patients. Level of evidence III. Treatment study: Case-control study. [ABSTRACT FROM AUTHOR]

The in vivo and post mortem performance and serum immunoglobulin G (IgG) concentration in kids born from goats fed conventional (group C) or genetically modified (group T) soybean meal were evaluated. The goat colostrum quality, in terms of chemical composition, as well as immunoglobulin concentration, and the presence of feed DNA fragments were also investigated. Kid birth weights were similar, while significantly ( P < 0.05) higher in those born from goats in group C at day 30 and at slaughtering. In addition, kids from mothers fed conventional soybean recorded significant ( P < 0.05) higher height at the withers and chest width. Concerning the post mortem measurements, only carcass weights were significantly affected by the treatment resulting in lighter T kids ( P < 0.05). Colostrum from the treated groups recorded a significantly ( P < 0.01) lower percentage of protein and fat. Similarly, both chemical parameters significantly differed in milk collected 15 days after kidding, although these differences disappeared in the successive samplings. Both colostrum and kids serum IgG concentration were significantly ( P < 0.01) lower in the treated groups. Transgenic target DNA sequences (35S and CP4 EPSPS) were not detected in colostrum from goats that received a diet containing conventional soybean meal. By contrast, transgenic DNA fragments were amplified ( P < 0.05) in samples from goats that received the transgenic soybean. [ABSTRACT FROM AUTHOR]

Power nonnegative matrices are defined as complex matrices having at least one nonnegative integer power. We exploit the possibility of deriving a Perron–Frobenius-like theory for these matrices, obtaining three main results and drawing several consequences. We study, in particular, the relationships with the set of matrices having eventually nonnegative powers, the inverse of M-type matrices and the set of matrices whose columns (rows) sum up to one. [ABSTRACT FROM AUTHOR]

ABSTRACT To describe the morphology of the proximal femoral epiphysis in a rabbit model from the ischemic insult to the end of the revascularization process. Ischemia of the femoral head was induced in 32 rabbits at the 8th day of life, by sectioning the joint capsule and the ligamentum teres and dislocating the femoral head. Rabbits were sacrificed at 4, 8, 12, 18, 21, 26, 34, and 48 days after surgery and femoral heads were observed histologically. During the first days following the ischemic injury, large areas underwent necrotic changes. Both epiphyseal and physeal cartilage were thicker than normal and less trabecular bone formation was evident. Bone marrow was also diffusely necrotic within the secondary center of ossification. After day 12th, reparative process started with formation of extensive areas of fibrocartilage and several secondary centers of ossifications. At that stage femoral head deformity was already evident. In the following days the secondary centers of ossification cohalesced and epiphyseal and physeal cartilage resumed a normal appearance, but the femur showed a permanent deformity. In newborn rabbits, the ischemic injury to the femoral head blocked the ossification of the epiphyseal and physeal cartilage associated to necrotic bone marrow within the secondary center of ossification of the femoral head as well as to extensive areas of necrosis of epiphyseal and physeal cartilage. Extensive areas of fibrocartilage and small newly formed ossification centers within the femoral epiphysis were the results of the revascularization process, and femoral head deformity became stable afterward. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:535-541, 2015. [ABSTRACT FROM AUTHOR]

Transparent MOCVD-grown NiO films have been functionalized with the luminescent (1,10-phenanthroline)tris(2-thenoyltrifluoroacetonato)europium(III) complex [Eu(TTA)3phen] by combining sputter activation with a solution synthetic route. To introduce the Eu complex only on selected regions, some areas of the NiO surface were activated by Ar+ ion sputtering and then functionalized with 3-phosphonopropionic acid (CPPA) followed by the anchoring of Eu(TTA)3phen through a ligand-exchange reaction between β-diketonato ligands and the carboxylic groups of CPPA. The functionalized material was characterized by X-ray photoelectron, UV/Vis and luminescence spectroscopy. XPS measurements indicated that CPPA prefunctionalization and, in turn, the Eu(TTA)3phen anchoring occurs only on the sputter-activated region, while no anchoring takes place on the unactivated surface. The optical properties of the Eu(TTA)3phen-NiO system were evaluated by UV/Vis and luminescence spectroscopy. [ABSTRACT FROM AUTHOR]

Variation of mechanical properties in materials can be detected non-destructively using ultrasonic measurements. In particular, changes in elastic wave velocity can occur due to damage, i.e., microcracking and particles debonding. Here the challenge of characterizing damage in geomaterials, i.e., rocks and soils, is addressed. Geomaterials are naturally heterogeneous media in which the deformation can localize, so that few measurements of acoustic velocity across the sample are not sufficient to capture the heterogeneities. Therefore, an ultrasonic tomography procedure has been implemented to map the spatial and temporal variations in propagation velocity, which provides information on the damage process. Moreover, double beamforming has been successfully applied to identify and isolate multiple arrivals that are caused by strong heterogeneities (natural or induced by the deformation process). The applicability of the developed experimental technique to laboratory geomechanics testing is illustrated using data acquired on a sample of natural rock before and after being deformed under triaxial compression. The approach is then validated and extended to time-lapse monitoring using data acquired during plane strain compression of a sample including a well defined layer with different mechanical properties than the matrix. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the feasibility of real-time sonoelastography in the assessment of the mechanical tendon properties in small unilateral supraspinatus tears, to describe the sonoelastographic properties of the torn supraspinatus tendons and to correlate real-time sonoelastography findings with clinical results and demographic data. Methods: All the patients presenting for a unilateral rotator cuff tear were prospectively scrutinized. Clinical evaluation included complete physical examination, VAS, Quick DASH, Constant-Murley score, Simple Shoulder Test, ASES score and UCLA score. Radiological evaluation was performed with conventional ultrasounds and real-time sonoelastography; this is a noninvasive method that uses ultrasounds to evaluate the mechanical properties of tissues, reflecting their quality, that can be semi-quantitatively estimated using the strain index. During the enrolment period, 92 patients were scrutinized, and 50 were included in the study. Results: A negative correlation between strain index and VAS for pain, a strong positive correlation between strain index and Constant-Murley score and ASES score were found. Comparable results were observed in male and female patients, but in males, we found a strong positive correlation also for Simple Shoulder Test and UCLA score. Conclusions: Real-time sonoelastography was a feasible method applicable in the assessment of tendon quality in small supraspinatus tears, and its findings correlated with the clinical results of the patients. In day-by-day clinical practice, this information is very important because quality of tendons is one of the most important prognostic factors for surgeons performing rotator cuff repair. Level of evidence: III. [ABSTRACT FROM AUTHOR]

A second-order random walk on a graph or network is a random walk where transition probabilities depend not only on the present node but also on the previous one. A notable example is the non-backtracking random walk, where the walker is not allowed to revisit a node in one step. Second-order random walks can model physical diffusion phenomena in a more realistic way than traditional random walks and have been very successfully used in various network mining and machine learning settings. However, numerous questions are still open for this type of stochastic processes. In this work, we extend well-known results concerning mean hitting and return times of standard random walks to the second-order case. In particular, we provide simple formulas that allow us to compute these numbers by solving suitable systems of linear equations. Moreover, by introducing the 'pullback' first-order stochastic process of a second-order random walk, we provide second-order versions of the renowned Kac's and Random Target Lemmas. [ABSTRACT FROM AUTHOR]

The effect of pasture fatty acid profile along the year on the Stearoyl-CoA desaturase (SCD) expression was evaluated over 5 months using 30 pluriparous goats, delivered in February. The animals had free access to pasture constituted by 60% Leguminosae and 40% Gramineae, and received 500 g/head/day of concentrate. From the second half of April, goats were milked twice a day for 5 months. Daily milk yield was recorded and, monthly, representative individual milk and pasture samples were analysed for chemical composition and fatty acid profile. The SCD expression was studied by extraction of mRNA from milk somatic cells and analysed by RT-PCR. Average milk yield, fat and protein were 1420 (g/d), 4.45 (%) and 3.62 (%), respectively. Milk yield decreased along the lactation ( P < 0.01) while milk fat was higher in August. Milk total CLA showed the highest levels ( P < 0.01) in June and August (mg/100 g fat: 0.98 and 1.21, respectively) as consequence of the highest levels of pasture C18:2 and C18:3 in June (% of total FA: 34.1 and 42.7, respectively) and August (% of total FA: 42.7 and 46.3, respectively). The grazing season as well as lactation stage affected the SCD mRNA abundance determined from milk somatic cells with values (arbitrary units) that progressively decreased from April (1.95) until June (1.40), increased in July (1.70) and decreased again in August (0.83). [ABSTRACT FROM AUTHOR]

One of the most relevant tasks in network analysis is the detection of community structures, or clustering. Most popular techniques for community detection are based on the maximization of a quality function called modularity, which in turn is based upon particular quadratic forms associated to a real symmetric modularity matrix M, defined in terms of the adjacency matrix and a rank-one null model matrix. That matrix could be posed inside the set of relevant matrices involved in graph theory, alongside adjacency and Laplacian matrices. In this paper we analyze certain spectral properties of modularity matrices, which are related to the community detection problem. In particular, we propose a nodal domain theorem for the eigenvectors of M; we point out several relations occurring between the graph's communities and nonnegative eigenvalues of M; and we derive a Cheeger-type inequality for the graph modularity. [ABSTRACT FROM AUTHOR]

We have combined the metal-coordinating features of phenanthroline with the remarkable complexing properties of tetraphosphonate (Tiiii) cavitands towards N-methylammonium salts with the aim of assembling novel luminescent ternary complexes. The formation of such complexes was first tested in solution: the charged sarcosine derivative 1, bearing a phenanthroline moiety, was complexed by the cavitand Tiiii- A, followed by coordination of EuIII-tris(β-diketonate) complex 2. The occurrence of the self-assembly has been proven by NMR spectroscopy, mass spectrometry and photophysical measurements. The transfer of this binding protocol to the surface showed the complete orthogonality of these interactions, as verified by control experiments on complexation-inactive surfaces. The formation of the ternary complexes on the silicon surface was monitored by means of X-ray photoelectron spectroscopy and luminescence spectroscopy. The emission properties of the silicon-bound Si-Tiiii- B·1·2 and the corresponding ternary complex Tiiii- A·1·2 in solution are similar, which indicates that the transfer of the self-assembly process onto silicon does not significantly perturb the EuIII coordination environment. The self-assembly protocol illustrated here can be extended to a wide variety of lanthanide ions and can be implemented for applications in sensing, bioimaging and optoelectronic devices. [ABSTRACT FROM AUTHOR]

A chiral organic–inorganic hybrid material, based on a porous silicon surface functionalized with a chiral cavitand, was designed and synthesized. The affinity of this device in water toward a bromine-marked alkyl-ammonium salt has been evaluated using XPS detection. UV and CD measurements highlight the enantioselective extraction from a racemic mixture in water of the S-enantiomer of the selected guest (ee ≥ 80%). [ABSTRACT FROM AUTHOR]

Simple Summary: Linseed has been utilized in ruminant nutrition to improve the production and quality of milk. In regard to the increasing concerns of consumers for the healthy aspects of foods as well as for animal welfare, in this research, we showed that linseed supplementation increased fat content but did not improve the milk concentration of odd- and branched-chain fatty acids (OBCFA), which are known to produce healthy effects in humans. Importantly, linseed did not show negative effects on animals' health, suggesting it can be safely used in goats' diet. The purpose of this study was to investigate the effects of linseed supplementation on milk yield and quality, serum biochemistry and, in particular, to evaluate its possible effects on the production of odd- and branched-chain fatty acids (OBCFA) in the milk of Cilentana grazing goats. Twelve pregnant Cilentana dairy goats were divided into two groups (CTR, control, and LIN, linseed supplementation group). After kidding, the goats had free access to the pasture and both groups received a supplement of 400 g/head of concentrate, but the one administered to the LIN group was characterized by the addition of linseed (in a ratio of 20% as fed) to the ingredients. During the trial, milk samples were taken from April to August in order to evaluate milk production, composition, and fatty acid profile. In addition, blood samples were taken for evaluating the effects of linseed supplementation on goats' health status. The health status of the goats was not influenced by the linseed supplementation, as confirmed by blood analyses. Concerning the effects on milk, the supplementation positively affected (p < 0.001) milk production and fat percentage and the fatty acid profile was markedly influenced by the lipid supplementation. In particular, milk from the LIN group was characterized by significantly lower concentrations of saturated fatty acids (FA; p < 0.001) and higher proportions of monounsaturated FA, polyunsaturated FA, and conjugated linoleic acids (CLAs) than milk from the CTR group (p < 0.001). In contrast, the OBCFA were negatively influenced by the linseed supplementation (p < 0.0001). Further studies are needed to test the effects of different fat sources and other nutrients on the diets. [ABSTRACT FROM AUTHOR]

Background: Discoid lateral meniscus is common in children. Arthroscopic partial resection is indicated in symptomatic cases generally achieving satisfactory results. Case presentation: We present a case of an incomplete discoid lateral meniscus of the right knee in an 11 year-old boy, treated with arthroscopic partial resection, which developed a re-growth of the remnant, restoring the pre-operative incomplete discoid shape. To the best of our knowledge this is the first report about re-growth of a discoid meniscus after surgery. Debate still exists regarding the etiology of a discoid meniscus. Some authors proposed it is the persistence of the normal stage during fetal development. However, most other authors believe it is anomalous and arises through variant morphogenesis. The regrowth of the discoid lateral meniscus following surgery in this patient seems to prove this latter theory. The residual growth of the knee involves also the lateral meniscus and that may have contributed to restoring the meniscus to the previous condition. Conclusion: This case report demonstrates discoid meniscal re-growth in a child. The growth spurt may have an impact on meniscal regeneration. Re-growth of the discoid lateral meniscus in our patient favors the hypothesis of variant morphogenesis. [ABSTRACT FROM AUTHOR]

One of the main problems in tokamak fusion devices concerns the capability to operate at a high plasma density, which is observed to be limited by the appearance of catastrophic events causing loss of plasma confinement. The commonly used empirical scaling law for the density limit is the Greenwald limit, predicting that the maximum achievable line-averaged density along a central chord depends only on the average plasma current density. However, the Greenwald density limit has been exceeded in tokamak experiments in the case of peaked density profiles, indicating that the edge density is the real parameter responsible for the density limit. Recently, it has been shown on the Frascati Tokamak Upgrade (FTU) that the Greenwald density limit is exceeded in gas-fuelled discharges with a high value of the edge safety factor. In order to understand this behaviour, dedicated density limit experiments were performed on FTU, in which the high density domain was explored in a wide range of values of plasma current (Ip = 500-900 kA) and toroidal magnetic field (BT = 4-8 T). These experiments confirm the edge nature of the density limit, as a Greenwald-like scaling holds for the maximum achievable line-averaged density along a peripheral chord passing at r/a ~ 4/5. On the other hand, the maximum achievable line-averaged density along a central chord does not depend on the average plasma current density and essentially depends on the toroidal magnetic field only. This behaviour is explained in terms of density profile peaking in the high density domain, with a peaking factor at the disruption depending on the edge safety factor. The possibility that the MARFE (multifaced asymmetric radiation from the edge) phenomenon is the cause of the peaking has been considered, with the MARFE believed to form a channel for the penetration of the neutral particles into deeper layers of the plasma. Finally, the magnetohydrodynamic (MHD) analysis has shown that also the central line-averaged density at the onset of the MHD activity depends only on the toroidal magnetic field. [ABSTRACT FROM AUTHOR]