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Background: Magnetic resonance spectroscopy (MRS) provides non-invasive information about metabolic features in different regions of the brain affected by mesial temporal sclerosis (MTS). Purpose: To review articles analyzing the most common alterations in biochemical parameters in MTS and the applications of MRS in presurgical assessment. Methods: We undertook a systematic literature search for MRS in MTS in PubMed, SCOPUS, and Cochrane based on the MESH terms ""Magnetic Resonance Spectroscopy", "Proton Magnetic Resonance Spectroscopy", "Carbon-13 Magnetic Resonance Spectroscopy", "1H-MRS", "31P-MRS", "mesial temporal sclerosis", "hippocampal sclerosis", "mesial temporal seizure", and "mesial temporal epilepsy". Results: Of the initial 134 articles found, 30 were selected after the exclusion process. Of these, 13 detected a decrease in N-acetylaspartate (NAA), 9 showed a decreased in the ratio NAA/Cho+Cr, and 8 demonstrated a decreased in the ratio NAA/Cr, all of them in the ipsilateral hippocampus. Nine studies also found reduced NAA levels in extrahippocampal regions. Conclusions: The main findings were a decrease in NAA in the ipsilateral hippocampus. In addition, NAA levels were low outside the hippocampus so MTS could be a more extensive disease. Patients without MTS also presented a decrease in NAA in the ipsilateral hippocampus although NAA was even lower in the MTS patients. Thus, MRS could be useful in the presurgical evaluation to locate the epileptogenic focus, but not specific for the diagnosis of MTS. [ABSTRACT FROM AUTHOR]

A forward-looking miniature histotripsy transducer has been developed that incorporates an acoustic lens and dual-frequency stacked transducers. An acoustic lens is used to increase the peak negative pressure through focal gain and the dual-frequency transducers are designed to increase peak negative pressure by summing the pressure generated by each transducer individually. Four lens designs, each with an ${f}$ -number of approximately 1, were evaluated in a PZT5A composite transducer. The finite-element model (FEM) predicted axial beamwidths of 1.61, 2.40, 2.84, and 2.36 mm for the resin conventional, resin Fresnel, silicone conventional, and silicone Fresnel lenses, respectively; the measured axial beamwidths were 1.30, 2.28, 2.71, and 2.11 mm, respectively. Radial beamwidths from the model were between 0.32 and 0.35 mm, while measurements agreed to within 0.2 mm. The measured peak negative was 0.150, 0.124, 0.160, and 0.160 MPa/V for the resin conventional, resin Fresnel, silicone conventional, and silicone Fresnel lenses, respectively. For the dual-frequency device, the 5-MHz (therapy) transducer had a measured peak negative pressure of 0.136 MPa/V for the PZT5A composite and 0.163 MPa/V for the PMN-PT composite. The 1.2-MHz (pump) transducer had a measured peak negative pressure of 0.028 MPa/V. The pump transducer significantly lowered the cavitation threshold of the therapy transducer. The dual-frequency device was tested on an ex vivo rat brain, ablating tissue at up to 4-mm depth, with lesion sizes as small as $500~\mu \text{m}$. [ABSTRACT FROM AUTHOR]

Recent studies by the authors developing the theory and applications of block elements in problems of mechanics and physics have unexpectedly resulted in the possibility of interpretation of one more feature of these mechanical and mathematical objects. Following the idea of Benoit Mandelbrot on fractality, i.e., self-similarity in nature, the investigation of block elements as objects with fractal properties is carried out. It is shown that known natural phenomena, processes, and objects described by boundary-value problems for partial differential equations and sets of such equations have self-similar packed block elements as solutions. Moreover, the special role of packed block elements generated by the boundary-value problems for the simplest wave equations, or Helmholtz equations, is highlighted. In the multitude of packed block elements for the boundary-value problems of natural processes, they are objects of a discrete topological space and have the maximum topology representing all the other block elements of the multitude by their unions. At the same time, the wave equation or the Helmholtz equation are analogues of the Schrödinger equation, which is the basis of quantum mechanics. The Schrödinger equation describes the states of elementary particles in quantum mechanics. In this regard, a situation arises in which the fundamental principle of both the quantum world and the specified natural processes are self-similar named equations, which accomplish their functions on the corresponding scales. The packed block elements generated by the boundary-value problems for the same equations as for the Schrödinger equation implement their functions in a continuous medium, and the states of elementary particles are described by similar equations in quantum mechanics. [ABSTRACT FROM AUTHOR]

Background: While recommended by international societal guidelines in the paediatric population, the use of venoarterial extracorporeal membrane oxygenation (VA ECMO) as mechanical circulatory support for refractory septic shock in adults is controversial. We aimed to characterise the outcomes of adults with septic shock requiring VA ECMO, and identify factors associated with survival.Methods: We searched Pubmed, Embase, Scopus and Cochrane databases from inception until 1st June 2021, and included all relevant publications reporting on > 5 adult patients requiring VA ECMO for septic shock. Study quality and certainty in evidence were assessed using the appropriate Joanna Briggs Institute checklist, and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, respectively. The primary outcome was survival to hospital discharge, and secondary outcomes included intensive care unit length of stay, duration of ECMO support, complications while on ECMO, and sources of sepsis. Random-effects meta-analysis (DerSimonian and Laird) were conducted.Data Synthesis: We included 14 observational studies with 468 patients in the meta-analysis. Pooled survival was 36.4% (95% confidence interval [CI]: 23.6%-50.1%). Survival among patients with left ventricular ejection fraction (LVEF) < 20% (62.0%, 95%-CI: 51.6%-72.0%) was significantly higher than those with LVEF > 35% (32.1%, 95%-CI: 8.69%-60.7%, p = 0.05). Survival reported in studies from Asia (19.5%, 95%-CI: 13.0%-26.8%) was notably lower than those from Europe (61.0%, 95%-CI: 48.4%-73.0%) and North America (45.5%, 95%-CI: 16.7%-75.8%). GRADE assessment indicated high certainty of evidence for pooled survival.Conclusions: When treated with VA ECMO, the majority of patients with septic shock and severe sepsis-induced myocardial depression survive. However, VA ECMO has poor outcomes in adults with septic shock without severe left ventricular depression. VA ECMO may be a viable treatment option in carefully selected adult patients with refractory septic shock. [ABSTRACT FROM AUTHOR]

According to both trial and clinical data on direct oral anticoagulants (DOACs) elderly patients are at greatest risk of bleeding. It is unclear whether age intrinsically affects anticoagulation response. To investigate the age-related sensitivity to DOACs, we compared the pharmacological activity of the direct factor Xa inhibitor, rivaroxaban, between young and elderly subjects ex-vivo. 36 fit elderly and 30 fit young subjects [median (IQR) age: 83(75–87) vs 30(26–38) years] provided a blood sample. Clotting parameters were measured in the resultant plasma samples incubated with rivaroxaban (100–500 ng/ml). Parametric, non-parametric tests and regression lines adjusted for rivaroxaban concentration and baseline values were used to compare data. Rivaroxaban produced a greater prolongation of both Prothrombin Time (PT) and modified Prothrombin Time (mPT) (both p < 0.001) in the elderly compared to young subjects (with difference in mean PT increasing from 1.6 to 6.1s and for mPT from 23.5 to 71.1s at 100 ng/ml and 500 ng/ml plasma rivaroxaban concentration, respectively). Factor X and factor II activity was significantly lower in the elderly in the presence of rivaroxaban (p < 0.001 for both). Rivaroxaban prolonged time-based parameters and suppressed the amount of thrombin generation to a significantly greater extent in the elderly compared to young subjects [%change from baseline for Endogenous Thrombin Potential (ETP): − 35.0 ± 4.4 vs − 29.8 ± 7.4 nM*min; p = 0.002]. The use of validated DOAC assays will be of considerable benefit for monitoring elderly patients who, because of their increased sensitivity to rivaroxaban, may require lower doses of the drug for therapeutic anticoagulation. [ABSTRACT FROM AUTHOR]

(B) Graphical representations of protein stability (thermal profile heat map) and protein structural features (structural barcodes) for each protein measured in TPP and LiP-MS experiments. Biophysical proteomics methods are also suitable to study protein-protein interactions based on the simple rationale that protein-forming complexes have often similar thermal stabilities, thus co-aggregate or are in general more protected from proteolysis. To this end, proteomics approaches have been frequently used to map protein expression in multiple experimental conditions and to identify protein-protein interactions. While informative, protein amounts and physical protein associations do not provide a full picture of protein function. [Extracted from the article]

In the title compound, C14H17N3O5S, the five-membered ring is essentially planar. The substituents at the nitrogen atoms subtend a C—N—N—S torsion angle of 95.52 (6)°. The amino group forms an intramolecular hydrogen bond to a sulfonyl oxygen atom; two intermolecular hydrogen bonds from the amino group, to the other S=O group and to the oxo substituent, form a layer structure parallel to the ab plane. The structure determination confirms that the title compound is N- rather than O-alkylated. [ABSTRACT FROM AUTHOR]

We prove that certain problems naturally arising in knot theory are NP–hard or NP–complete. These are the problems of obtaining one diagram from another one of a link in a bounded number of Reidemeister moves, determining whether a link has an unlinking or splitting number k, finding a k-component unlink as a sublink, and finding a k-component alternating sublink. [ABSTRACT FROM AUTHOR]

Recurrent neural networks with associative memory properties are typically based on fixed-point dynamics, which is fundamentally distinct from the oscillatory dynamics of the brain. There have been proposals for oscillatory associative memories, but here too, in the majority of cases, only binary patterns are stored as oscillatory states in the network. Oscillatory neural network models typically operate at a single/common frequency. At multiple frequencies, even a pair of oscillators with real coupling exhibits rich dynamics of Arnold tongues, not easily harnessed to achieve reliable memory storage and retrieval. Since real brain dynamics comprises of a wide range of spectral components, there is a need for oscillatory neural network models that operate at multiple frequencies. We propose an oscillatory neural network that can model multiple time series simultaneously by performing a Fourier-like decomposition of the signals. We show that these enhanced properties of a network of Hopf oscillators become possible by operating in the complex-variable domain. In this model, the single neural oscillator is modeled as a Hopf oscillator, with adaptive frequency and dynamics described over the complex domain. We propose a novel form of coupling, dubbed "power coupling," between complex Hopf oscillators. With power coupling, expressed naturally only in the complex-variable domain, it is possible to achieve stable (normalized) phase relationships in a network of multifrequency oscillators. Network connections are trained either by Hebb-like learning or by delta rule, adapted to the complex domain. The network is capable of modeling N-channel electroencephalogram time series with high accuracy and shows the potential as an effective model of large-scale brain dynamics. [ABSTRACT FROM AUTHOR]

Adolescence has been linked to an enhanced tolerance of uncertainty and risky behavior and is possibly connected to an increased response toward rewards. However, previous research has produced inconsistent findings. To investigate whether these findings are due to different reward probabilities used in the experimental design, we extended a monetary incentive delay (MID) task by including three different reward probabilities. Using functional magnetic resonance imaging, 25 healthy adolescents and 22 adults were studied during anticipation of rewards in the VS. Differently colored cue stimuli indicated either a monetary or verbal trial and symbolized different reward probabilities, to which the participants were blinded. Results demonstrated faster reaction times for lower reward probabilities (33%) in both age groups. Adolescents were slower through all conditions and had less activation on a neural level. Imaging results showed a three-way interaction between age group x condition x reward probability with differences in percent signal change between adolescents and adults for the high reward probabilities (66%, 88%) while adolescents demonstrated differences for the lowest (33%). Therefore, previous inconsistent findings could be due to different reward probabilities, which makes examining these crucial for a better understanding of adolescent and adult behavior. [ABSTRACT FROM AUTHOR]

In this paper we present a general approach to rigorously validate Hopf bifurcations as well as saddle-node bifurcations of periodic orbits in systems of ODEs. By a combination of analytic estimates and computer-assisted calculations, we follow solution curves of cycles through folds, checking along the way that a single nondegenerate saddle-node bifurcation occurs. Similarly, we rigorously continue solution curves of cycles starting from their onset at a Hopf bifurcation. We use a blowup analysis to regularize the continuation problem near the Hopf bifurcation point. This extends the applicability of validated continuation methods to the mathematically rigorous computational study of bifurcation problems. [ABSTRACT FROM AUTHOR]

Motion groups of links in the three sphere S 3 are generalizations of the braid groups, which are motion groups of points in the disk D 2 . Representations of motion groups can be used to model statistics of extended objects such as closed strings in physics. Each 1-extended (3 + 1) -topological quantum field theory (TQFT) will provide representations of motion groups, but it is difficult to compute such representations explicitly in general. In this paper, we compute representations of the motion groups of links in S 3 with generalized axes from Dijkgraaf–Witten (DW) TQFTs inspired by dimension reduction. A succinct way to state our result is as a step toward a twisted generalization (Conjecture 1) of a conjecture for DW theories of dimension reduction from (3 + 1) to (2 + 1) : DW G 3 + 1 ≅ ⊕ [ g ] ∈ [ G ] DW C (g) 2 + 1 , where the sum runs over all conjugacy classes [ g ] ∈ [ G ] of G and C(g) the centralizer of any element g ∈ [ g ] . We prove a version of Conjecture 1 for the mapping class groups of closed manifolds and the case of torus links labeled by pure fluxes. [ABSTRACT FROM AUTHOR]

Arterial and venous thromboembolism is a common and serious clinical condition where anticoagulation is administered for its treatment and prophylaxis. Anticoagulants prevent the formation of new thrombi and thus the extension of the existing thrombus. Direct-acting oral anticoagulants (DOAC) include dabigatran, which is a thrombin inhibitor, and rivaroxaban, apixaban, and edoxaban, which are anti-Xa agents. These are administered in the secondary prophylaxis and treatment of various diseases of thrombus. Although it is specified that they reduce the risk of bleeding due to all causes, many important studies have also reported that they increase the risk of gastrointestinal system (GIS) bleeding. Therefore, similar to Vitamin K antagonists (VKA), their use is contraindicated in active bleeding, active ulcers, hemorrhagic angiodysplasia, and recurrent bleeding requiring recurrent transfusion. However, these contraindications are mostly transient. We aimed to analyse the risk, prophylaxis and management of the active GIS bleeding in patients taking DOAC in this article. [ABSTRACT FROM AUTHOR]

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The mechanical model of a two-degree-of-freedom vibration system with multiple rigid stops was established, and the effects of the multiple rigid stops to dynamic characteristics of two mass blocks of the system were studied. The judgment conditions and differential equations of motion of the system masses impacting rigid stops were analyzed. Based on the multiparameter and multiobjective collaborative simulation analysis, the correlation between the dynamic characteristics of the vibration system and the model parameters is studied. The basic periodic and subharmonic impact motions are analyzed with emphasis on the influences of dynamical parameters on the mode diversity and the distribution characteristics, and the law of emergence and competition of various periodic impact motions on the parametric plane is revealed. The singular points, the hysteresis transition domains, and the accompanying codimension-two bifurcations, caused by the irreversibility of the transition between adjacent basic periodic impact motions in the low-frequency domain, are analyzed. The reasonable parameter matching range, associated with dynamic characteristic optimization of the system, is determined. [ABSTRACT FROM AUTHOR]

Let X ε : S 2 n - 1 → T S 2 n - 1 be a smooth perturbation of X 0 , the vector field associated to the dynamical system defined by n identical uncoupled harmonic oscillators constrained to their 1-energy level. We are dealing with the case when any orbit of every X ε is closed: while in general is false that the vector fields of the perturbation are orbitally equivalent to the unperturbed X 0 (Villarini in Ergod Theory Dyn Syst 39:1–32, 2019), we prove that this rigidity behaviour is indeed true if each X ε restricted to a codimension 2 sphere in S 2 n - 1 is orbitally conjugated to a subsystem of X 0 made by n - 1 harmonic oscillators. In other words: to have a non-rigid, or truly non-linear, perturbation of X 0 at least two harmonic oscillators must be destroyed by the perturbation. We use this rigidity result to prove a linearization theorem for real analytic multicentres. Finally we give an example of a real analytic perturbation of X 0 showing discontinuous changing of integer invariants of the vector fields of the perturbation. [ABSTRACT FROM AUTHOR]

Summary: The pandemic from the SARS-CoV‑2 virus is currently challenging healthcare systems all over the world. Maintaining appropriate staffing and resources in healthcare facilities is essential to guarantee a safe working environment for healthcare personnel and safe patient care. Extracorporeal membrane oxygenation (ECMO) represents a valuable therapeutic option in patients with severe heart or lung failure. Although only a limited proportion of COVID-19 patients develop respiratory or circulatory failure that is refractory to conventional treatment, it is of utmost importance to clearly define criteria for the use of ECMO in this steadily growing patient population. The ECMO working group of the Medical University of Vienna has established the following recommendations for ECMO support in COVID-19 patients. [ABSTRACT FROM AUTHOR]

Background: How, and the extent to which, evolution acts on DNA and protein sequences to ensure mutational robustness and evolvability is a long-standing open question in the field of molecular evolution. We addressed this issue through the first structurome-scale computational investigation, in which we estimated the change in folding free energy upon all possible single-site mutations introduced in more than 20,000 protein structures, as well as through available experimental stability and fitness data. Results: At the amino acid level, we found the protein surface to be more robust against random mutations than the core, this difference being stronger for small proteins. The destabilizing and neutral mutations are more numerous in the core and on the surface, respectively, whereas the stabilizing mutations are about 4% in both regions. At the genetic code level, we observed smallest destabilization for mutations that are due to substitutions of base III in the codon, followed by base I, bases I+III, base II, and other multiple base substitutions. This ranking highly anticorrelates with the codon-anticodon mispairing frequency in the translation process. This suggests that the standard genetic code is optimized to limit the impact of random mutations, but even more so to limit translation errors. At the codon level, both the codon usage and the usage bias appear to optimize mutational robustness and translation accuracy, especially for surface residues. Conclusion: Our results highlight the non-universality of mutational robustness and its multiscale dependence on protein features, the structure of the genetic code, and the codon usage. Our analyses and approach are strongly supported by available experimental mutagenesis data. [ABSTRACT FROM AUTHOR]

Medical imaging methods have improved the detection of human diseases with increasing accuracy. The ability to probe molecular processes noninvasively or using tissue‐selective imaging agents and nanoparticles has made it possible to localize, identify the stage, and determine the functional status of pathological lesions. The challenges in detecting cancer particularly have driven the development of diverse imaging technologies. While earlier cancer imaging methods enabled preoperative evaluation, the need to track and visualize cancer location in the operating room itself has ushered in new systems capable of providing concurrent images of cancer during surgery. Intraoperative use of conventional clinical imaging modalities is often limited by bulky hardware design, prohibitive cost, lack of real‐time image display, and compatibility with conventional hardware interfaces. For these reasons, focus on fluorescence‐guided surgery (FGS) devices has increased to take advantage of real‐time, high‐resolution, functional imaging with hardware that has become increasingly amenable to miniaturization. In particular, the adaptation of wearable devices for FGS presents hands‐free capability for optimal navigation during cancer surgery. The evolution of head‐mounted devices in the operating room and adaptation for FGS is highlighted. Key challenges to wide clinical adoption of this imaging platform are identified and potential future directions are suggested. [ABSTRACT FROM AUTHOR]

In this paper, we study the number of equilibria of the replicator–mutator dynamics for both deterministic and random multi-player two-strategy evolutionary games. For deterministic games, using Descartes' rule of signs, we provide a formula to compute the number of equilibria in multi-player games via the number of change of signs in the coefficients of a polynomial. For two-player social dilemmas (namely the Prisoner's Dilemma, Snow Drift, Stag Hunt and Harmony), we characterize (stable) equilibrium points and analytically calculate the probability of having a certain number of equilibria when the payoff entries are uniformly distributed. For multi-player random games whose pay-offs are independently distributed according to a normal distribution, by employing techniques from random polynomial theory, we compute the expected or average number of internal equilibria. In addition, we perform extensive simulations by sampling and averaging over a large number of possible payoff matrices to compare with and illustrate analytical results. Numerical simulations also suggest several interesting behaviours of the average number of equilibria when the number of players is sufficiently large or when the mutation is sufficiently small. In general, we observe that introducing mutation results in a larger average number of internal equilibria than when mutation is absent, implying that mutation leads to larger behavioural diversity in dynamical systems. Interestingly, this number is largest when mutation is rare rather than when it is frequent. [ABSTRACT FROM AUTHOR]

The use of agricultural based biomass through combustion is playing an important role in the production of heat and electricity worldwide. The emission of particulate matter pollution from biomass combustion has drawn significant attention because of its harmful effects on human health and environment. Consequently, it becomes important to have a simple and cost effective solution to avoid the problems of air pollution due to the combustion of biomass. Using an Electrostatic Precipitator (ESP) is an effective method for the removal of particulate matter from industrial processes and boilers. This research proposes the development of a cost effective, simple and compact ESP, through practical installation and efficiency analysis. Experimental evaluation of the proposed ESP design is carried out for the removal of particulate matter from a biomass combustor. The results shown in this paper are promising and exhibit that a simple solution can achieve above 90% efficiency. The average particulate collection efficiency of our proposed ESP reached its peak stable value of 99.1% when tested with applied voltage of 25kV at an air velocity of 0.5 m/s. Moreover, it was observed and shown in this paper that when the voltage was increased beyond 25kV, the efficiency of the design lost its stability due to back corona effect. The filtration system proposed in this paper shows the ability of an efficient tool for controlling the flow of particulate pollutant matter from biomass combustion under particular conditions. [ABSTRACT FROM AUTHOR]

Many problems in fluid mechanics and acoustics can be modelled by Helmholtz scattering off poro-elastic plates. We develop a boundary spectral method, based on collocation of local Mathieu function expansions, for Helmholtz scattering off multiple variable poro-elastic plates in two dimensions. Such boundary conditions, namely the varying physical parameters and coupled thin-plate equation, present a considerable challenge to current methods. The new method is fast, accurate and flexible, with the ability to compute expansions in thousands (and even tens of thousands) of Mathieu functions, thus making it a favourable method for the considered geometries. Comparisons are made with elastic boundary element methods, where the new method is found to be faster and more accurate. Our solution representation directly provides a sine series approximation of the far-field directivity and can be evaluated near or on the scatterers, meaning that the near field can be computed stably and efficiently. The new method also allows us to examine the effects of varying stiffness along a plate, which is poorly studied due to limitations of other available techniques. We show that a power-law decrease to zero in stiffness parameters gives rise to unexpected scattering and aeroacoustic effects similar to an acoustic black hole metamaterial. [ABSTRACT FROM AUTHOR]

With the rapid development of high-power tractor, the fault diagnosis of high-power tractor has become more and more important for ensuring the operating safety and efficiency. PSO is an iterative optimization evolutionary algorithm, which can iterate through different particles to find the optimal solution. However, there is only one population in the standard PSO algorithm, and the information exchange between the populations is relatively single, which can easily lead to the stagnation of the development of the population. In this paper, due to high-power tractor diesel engine fault complexity, fault correlation, and multifault concurrency, a multigroup coevolution particle swarm optimization BP neural network for diesel engine fault diagnosis method was proposed. First, the USB-CAN device was used to collect data of 8 items of the diesel engine under five different working conditions, and the data was parsed through the SAE J1939 protocol; then, the BP neural network was reconstructed, and a competitive multiswarm cooperative particle swarm optimizer algorithm (COM-MCPSO) was used to optimize its structure and weights. Finally, the data of optimized neural network under five different fault conditions show that, compared with BP neural network and PSO optimized BP neural network, the fault diagnosis of COM-MCPSO optimized BP neural network not only improves the network training speed, but also enhances generalization ability and improves recognition accuracy. [ABSTRACT FROM AUTHOR]

As an extension of the discrete Sommerfeld problems on lattices, the scattering of a time-harmonic wave is considered on an infinite square lattice when there exists a pair of semi-infinite cracks or rigid constraints. Due to the presence of stagger, also called offset, in the alignment of the defect edges the asymmetry in the problem leads to a matrix Wiener–Hopf kernel that cannot be reduced to scalar Wiener–Hopf in any known way. In the corresponding continuum model the same problem is a well-known formidable one which possesses certain special structure with exponentially growing elements on the diagonal of kernel. From this viewpoint the present paper tackles a discrete analog of the same by reformulating the Wiener–Hopf problem and reducing it to a finite set of linear algebraic equations; the coefficients of which can be found by an application of the scalar Wiener–Hopf factorization. The considered discrete paradigm involving lattice waves is relevant for modern applications of mechanics and physics at small length scales. [ABSTRACT FROM AUTHOR]

We propose new and original mathematical connections between Hamilton–Jacobi (HJ) partial differential equations (PDEs) with initial data and neural network architectures. Specifically, we prove that some classes of neural networks correspond to representation formulas of HJ PDE solutions whose Hamiltonians and initial data are obtained from the parameters of the neural networks. These results do not rely on universal approximation properties of neural networks; rather, our results show that some classes of neural network architectures naturally encode the physics contained in some HJ PDEs. Our results naturally yield efficient neural network-based methods for evaluating solutions of some HJ PDEs in high dimension without using grids or numerical approximations. We also present some numerical results for solving some inverse problems involving HJ PDEs using our proposed architectures. [ABSTRACT FROM AUTHOR]

For a smooth projective quadric X, Alexander Vishik introduced the notion of connections. He discovered connections arising from the splitting pattern of X as well as the so-called excellent connections. Recently, Victor Petrov and Nikita Semenov found new connections arising from the J-invariantJ(X), which is a layer of the elementary discrete invariant E D (X) , both further Vishik's inventions. In this note, we give a new proof for Peterov–Semenov's connections and extend them to the remaining layers of E D (X) . Also, we briefly discuss connections on nonsmooth quadrics. [ABSTRACT FROM AUTHOR]

The important open canonical problem of wave diffraction by a penetrable wedge is considered in the high-contrast limit. Mathematically, this means that the contrast parameter, the ratio of a specific material property of the host and the wedge scatterer, is assumed small. The relevant material property depends on the physical context and is different for acoustic and electromagnetic waves for example. Based on this assumption, a new asymptotic iterative scheme is constructed. The solution to the penetrable wedge is written in terms of infinitely many solutions to (possibly inhomogeneous) impenetrable wedge problems. Each impenetrable problem is solved using a combination of the Sommerfeld–Malyuzhinets and Wiener–Hopf techniques. The resulting approximated solution to the penetrable wedge involves a large number of nested complex integrals and is hence difficult to evaluate numerically. In order to address this issue, a subtle method (combining asymptotics, interpolation and complex analysis) is developed and implemented, leading to a fast and efficient numerical evaluation. This asymptotic scheme is shown to have excellent convergent properties and leads to a clear improvement on extant approaches. [ABSTRACT FROM AUTHOR]

The precise understanding of the dopaminergic (DA) system and its pharmacological modifications is crucial for diagnosis and treatment of neuropsychiatric disorders, as well as for understanding basic processes, such as motivation and reward. We probed the functional connectivity (FC) of subcortical nuclei related to the DA system according to seed regions defined according to an atlas of subcortical nuclei. We conducted a large pharmaco‐fMRI study using a double‐blind, placebo‐controlled design, where we examined the effect of l‐DOPA, a dopamine precursor, and amisulpride, a D2/D3‐receptor antagonist on resting‐state FC in 45 healthy young adults using a cross‐over design. We examined the FC of subcortical nuclei with connection to the reward system and their reaction to opposing pharmacological probing. Amisulpride increased FC from the putamen to the precuneus and from ventral striatum to precentral gyrus. l‐DOPA increased FC from the ventral tegmental area (VTA) to the insula/operculum and between ventral striatum and ventrolateral prefrontal cortex and it disrupted ventral striatal and dorsal caudate FC with the medial prefrontal cortex. In an exploratory analysis, we demonstrated that higher self‐rated impulsivity goes together with a significant increase in VTA‐mid‐cingulate gyrus FC during l‐DOPA‐challenge. Therefore, our DA challenge modulated distinct large‐scale subcortical connectivity networks. A dopamine‐boost can increase midbrain DA nuclei connectivity to the cortex. The involvement of the VTA‐cingulum connectivity in dependence of impulsivity has implications for diagnosis and therapy in disorders like ADHD. [ABSTRACT FROM AUTHOR]

In the title compound, C13H15N3O5 S, the two rings face each other in a 'V0 form at the S atom, with one N-H…O S and one C-H…O S contact from the pyrazolyl substituents to the sulfonyl group. Two classical hydrogen bonds from the amine group, one of the form N-H…O S and one N-H…O Coxo, link the molecules to form layers parallel to the bc plane. [ABSTRACT FROM AUTHOR]

Scalar wave propagation across a semi-infinite step or step-like discontinuity on any one boundary of the square lattice waveguides is considered within nearest-neighbour interaction approximation. An application of the Wiener–Hopf method does yield an exact solution of the discrete scattering problem, using which, as the main result of the paper, the transmission coefficients for energy flux are obtained. It is assumed that a wave mode is incident from either side of the step and the question addressed is what fraction of incident energy is transmitted across the atomic step discontinuity. A total of ten configurations are presented that arise due to various placements of discrete Dirichlet and Neumann boundary conditions on the waveguide. Numerical illustrations of a measure of ‘conductance’ are provided. [ABSTRACT FROM AUTHOR]

Background: Hypoxia is a potent molecular signal for cellular metabolism, mitochondrial function, and migration. Conditions of low oxygen tension trigger regulatory cascades mediated via the highly conserved HIF-1 α post-translational modification system. In the adaptive immune response, B cells (Bc) are activated and differentiate under hypoxic conditions within lymph node germinal centers, and subsequently migrate to other compartments. During migration, they traverse through changing oxygen levels, ranging from 1-5% in the lymph node to 5-13% in the peripheral blood. Interestingly, the calcineurin inhibitor cyclosporine A is known to stimulate prolyl hydroxylase activity, resulting in HIF-1 α destabilization and may alter Bc responses directly. Over 60% of patients taking calcineurin immunosuppressant medications have hypo-gammaglobulinemia and poor vaccine responses, putting them at high risk of infection with significantly increased morbidity and mortality. Results: We demonstrate that O 2 tension is a previously unrecognized Bc regulatory switch, altering CXCR4 and CXCR5 chemokine receptor signaling in activated Bc through HIF-1 α expression, and controlling critical aspects of Bc migration. Our data demonstrate that calcineurin inhibition hinders this O 2 regulatory switch in primary human Bc. Conclusion: This previously unrecognized effect of calcineurin inhibition directly on human Bc has significant and direct clinical implications. [ABSTRACT FROM AUTHOR]

A semi-infinite crack in an infinite square lattice is subjected to a wave coming from infinity, thereby leading to its scattering by the crack surfaces. A partially damaged zone ahead of the crack tip is modelled by an arbitrarily distributed stiffness of the damaged links. While an open crack, with an atomically sharp crack tip, in the lattice has been solved in closed form with the help of the scalar Wiener-Hopf formulation (Sharma 2015 SIAM J. Appl. Math., 75, 1171-1192 (doi:10.1137/140985093); Sharma 2015 SIAM J. Appl. Math. 75, 1915-1940. (doi:10.1137/15M1010646)), the problem considered here becomes very intricate depending on the nature of the damaged links. For instance, in the case of a partially bridged finite zone it involves a 2 ×2 matrix kernel of formidable class. But using an original technique, the problem, including the general case of arbitrarily damaged links, is reduced to a scalar one with the exception that it involves solving an auxiliary linear system of N × N equations, where N defines the length of the damage zone. The proposed method does allow, effectively, the construction of an exact solution. Numerical examples and the asymptotic approximation of the scattered field far away from the crack tip are also presented. [ABSTRACT FROM AUTHOR]

All-trans-octatetraene 3,10-di(tert-butyl)-2,2,11,11-tetramethyl-3,5,7,9-dodecatetraene emits fluorescence in three different regions of the visible spectrum. Thus, it produces an extremely weak emission in the gas phase that can hardly be detected in the condensed phase; such an emission exhibits a negligible Stokes shift with respect to the 1Ag→1Bu absorption transition and can, in principle, be assigned to the 1Bu→1Ag emission for the compound. A second, structureless fluorescence emission, centered in the region of 525 nm, is observed in the gas phase and at somewhat higher wavelengths in the condensed phase [viz., 570 nm in 2-methylbutane (2MB) and 550 nm in squalane (SQ)]. While detectable, this emission increases significantly, with no change in spectral position, as the solution temperature is lowered; also, it is abruptly replaced by a new, strongly blueshifted emission at ∼490 nm in 2MB and 455 mm in SQ when the viscosity of the medium exceeds a given level. The fact that the two fluorescence emissions considerably depart from the expected behavior for a 1Bu→1Ag emission in an all-trans-polyene, and that one disappears while the other simultaneously appears as the medium becomes more rigid, suggests that the two emissions are produced by two different molecular structures and that the rigidity of the medium switches their production from the originally excited all-trans 1Bu form. The observed spectral behavior is consistent with a recently proposed model [J. Catalan, Chem. Phys. 335, 69 (2007)] in which the 1Bu excited state of octatetraene can give two distinct molecular conformers as a result of twisting about different C–C single bonds. [ABSTRACT FROM AUTHOR]

Chemical genetics takes advantage of small molecule-protein interactions to explore various biological processes. Although an attractive alternative to classical genetics in plants, the identification of small-molecule targets remains a challenge and limits the broad use of the compounds. The cellular thermal shift assay (CETSA), based on the principle that binding of small molecules could affect the thermal stability of proteins, has been applied for target validation in plant cells. Combined with high-resolution mass spectrometry, CETSA can detect small-molecule targets by monitoring the changes in the protein thermal stability caused by the interactions with small molecules at the proteome level. Here we describe the small-molecule target validation as well as the target identification with mass spectrometry by means of CETSA., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Effective preventive measures against implant-associated infection (IAI) are desperately needed. Therefore, the development of self-defending implants with intrinsic antibacterial properties has gained significant momentum. Biomaterials biofunctionalized with silver (Ag) have resulted in effective antibacterial biomaterials, yet regularly induce cytotoxicity. In this study, the use of both Ag and copper (Cu) nanoparticles (NPs) on TiO2 surfaces was investigated to generate antibacterial and osteoconductive biomaterials. Hence, additively manufactured Ti–6Al–4V volume-porous implants were biofunctionalized with plasma electrolytic oxidation (PEO) through the incorporation of varying ratios of Ag and/or Cu NPs in the TiO2 layer covering the implant surface. For all experimental groups, the surface morphology, chemical composition, ion release profile, generation of reactive ion species, antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) in vitro and ex vivo, as well as the response of pre-osteoblastic MC3T3-E1 cells in metabolic activity and differentiation assays were determined. PEO biofunctionalization resulted in rough and highly porous surfaces that released Ag and Cu ions for 28 days and generated hydroxyl as well as methyl radicals. A strong synergistic bactericidal behavior between Ag and Cu ions was detected, which allowed to decrease the concentration of Ag ions by 10-fold, while maintaining the same level of antibacterial activity. Antibacterial agar diffusion and quantitative assays indicated strong antibacterial activity in vitro for the implants containing Ag and Ag/Cu, while no antibacterial activity was observed for implants bearing only Cu NPs. Moreover, the biofunctionalized implants with ratios of up to 75% Ag and 25% Cu NP totally eradicated all bacteria in an ex vivo model using murine femora. Meanwhile, the biofunctionalized implants did not show any signs of cytotoxicity, while implants bearing only Cu NPs improved the metabolic activity after 7 and 11 days. The biomaterials developed here, therefore, exploit the synergistic behavior of Ag and Cu to simultaneously offer strong antibacterial behavior while fully mitigating the cytotoxicity of Ag against mammalian cells. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore whether reward learning would affect the processing of targets when an emotional stimulus was task irrelevant. In the current study, using a visual search paradigm to establish an association between emotional faces and reward, an emotional face appeared as a task-irrelevant distractor during the test after reward learning, and participants were asked to judge the orientation of a line on the face. In experiment 1, no significant difference was found between the high reward-fear distractor condition and the no reward-neutral condition, but the response times of the high reward-fear condition were significantly longer than those of the low reward-happy condition. In experiment 2, there was no significant difference in participants' performance between high reward-happy and no reward-neutral responses. In addition, response times of the low reward-fear condition wear significantly longer than those of the high reward-happy and no reward-neutral conditions. The results show that reward learning affects attention bias of task-irrelevant emotional faces even when reward is absent. Moreover, the high reward selection history is more effective in weakening the emotional advantage of the processing advantage than the low reward. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the viability of larval nematodes of ungulates under the infl uence of 14 fl avourings and source materials approved for use in and on foods. Minimum LD50 for L3Strongyloides papillosus (Wedl, 1856) were observed when using Cinnamaldehyde, α-Terpineol and Benzyl alcohol, for L1–2S. papillosus under the infl uence of Benzyl alcohol, Cinnamaldehyde, L-Linalool and Benzyl acetate, for L3Haemonchus contortus (Rudolphi, 1803) under the influence γ-Undecalactone and Cinnamaldehyde. Ethyl acetate, β-Ionone и D-Limonene had the lowest effect on all the studied stages of development of the nematodes: larvae did not die during 24 hours even at 1 % concentration of these substances. Further experiments with usage of mixtures of the substances studied in this article will contribute to the development of preparations with a stronger effect on larvae of nematode parasites of the digestive system of vertebrate animals. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate the validity, reliability, sensitivity and specificity of the European-Portuguese version of the Intelligibility in Context Scale (ICS-EP). Seventy-six children (age: M = 60.6, SD = 8.1 months), 25 having a parent or teacher concern about how they talked and 51 with no concern, were assessed with the phonetic-phonological test (TFF-ALPE) to calculate the following severity measures: percentage of phonemes correct (PPC), percentage of consonants correct (PCC), and percentage of vowels correct (PVC). Parents also filled out a questionnaire about their child's development (e.g. concern about how the child talks). The ICS was then completed by parents to estimate their children's intelligibility with different communicative partners. The results showed that item-level scores were different according to communicative partners. The mean ICS score for the whole sample was 4.5 (SD = 0.6), showing that children were "usually" to "always" intelligible. The ICS had excellent internal consistency (α = 0.96). Children with parental concern about their speech presented significantly lower mean scores (M = 3.91, SD = 0.59) than children without parental concerns (M = 4.78, SD = 0.36). There was a positive correlation between the ICS scores and PPC (r =.655),PCC(r =.654),andPVC(r = .588). A simple linear model was also obtained between the ICS mean score and the severity measures analyzed. High values were obtained for sensitivity (0.80) and specificity (0.84), using a cut-off point of 4.36. We conclude that the ICS-EP has good psychometric properties, suggesting it to be a valid tool for estimating children's intelligibility when talking with different communicative partners. Therefore, this version of the ICS can be used as a screening measure for children's speech intelligibility. [ABSTRACT FROM AUTHOR]

Let L/K be a finite Galois extension whose Galois group G is nonabelian and characteristically simple. By drawing tools from graph theory and group theory, we shall give a closed formula for the total number of Hopf-Galois structures on L/K with associated group isomorphic to G. [ABSTRACT FROM AUTHOR]

This paper is concerned with the spatial patterns of a predator–prey system with Beddington–DeAngelis functional response, in which the parameter k measuring the mutual interference between predators can play an essential role. By using the bifurcation theory and implicit function theorem we first consider the positive steady state solution bifurcating from the semitrivial steady state solution set of the system and prove that the positive steady state solution is constant. Then we show that nonconstant positive steady state solution may bifurcate from the constant positive steady state solution when k is neither small nor large. Finally, we show that spatially nonhomogeneous periodic orbits may also bifurcate from the constant positive steady state solution as k is not large. [ABSTRACT FROM AUTHOR]

Bursting oscillations in systems with multi-frequency slow excitations reflect multi-timescale dynamics. As there exist many kinds of multiple periodic excitations in actual dynamical systems, the analysis of dynamical behavior of such systems has received much attention. In this article, we first investigate the bursting in Sprott B system with a single excitation. We show that Hopf bifurcation delay may exhibit due to the effect of slow passage through the supercritical Hopf bifurcation. Interestingly, such delay behavior leads to a pinched "Hopf/Hopf"-hysteresis bursting when delay time is long enough. Then, we focus on the effects of the additional excitation β 2 cos (ω 2 t) on the zero-crossing pinched "Hopf/Hopf"-hysteresis bursting. We find that, under the effects of β 2 cos (ω 2 t) , "Hopf/Hopf"-bifurcation-delay-induced hysteresis behaviors may exhibit very interesting dynamical characteristics. In particular, each equilibrium branch may become the one with twists and turns. Then, the novel bursting pattern, turnover-of-zero-crossing pinched-"Hopf/Hopf"-hysteresis-induced bursting, is disclosed accordingly. In addition, we show that the equilibrium branches may cross each other spirally, leading to multiple intersection points under certain parameter conditions. There are two Hopf bifurcation points perching separately upon either side of the intersection points. This creates multiple delay-induced hysteresis behavior, and the other novel bursting pattern, cascaded pinched "Hopf/Hopf"-hysteresis bursting, is thus created. Finally, we investigate the complex amplitude-modulated bursting (CAMB) rhythms in Sprott B system with multi-frequency slow excitations. [ABSTRACT FROM AUTHOR]