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1
Asperti, Andrea, and Harry G. Mairson. "Parallel Beta Reduction Is Not Elementary Recursive." Information and Computation 170, no. 1 (2001): 49–80. http://dx.doi.org/10.1006/inco.2001.2869.
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Su, Ting-Yu, Pi-Lien Hung, Chien Chen, Ying-Jui Lin, and Syu-Jyun Peng. "Graph Theory-Based Electroencephalographic Connectivity and Its Association with Ketogenic Diet Effectiveness in Epileptic Children." Nutrients 13, no. 7 (2021): 2186. http://dx.doi.org/10.3390/nu13072186.
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Ketogenic diet therapies (KDTs) are widely used treatments for epilepsy, but the factors influencing their responsiveness remain unknown. This study aimed to explore the predictors or associated factors for KDTs effectiveness by evaluating the subtle changes in brain functional connectivity (FC) before and after KDTs. Segments of interictal sleep electroencephalography (EEG) were acquired before and after six months of KDTs. Analyses of FC were based on network-based statistics and graph theory, with a focus on different frequency bands. Seventeen responders and 14 non-responders were enrolled. After six months of KDTs, the responders exhibited a significant functional connectivity strength decrease compared with the non-responders; reductions in global efficiency, clustering coefficient, and nodal strength in the beta frequency band for a consecutive range of weighted proportional thresholds were observed in the responders. The alteration of betweenness centrality was significantly and positively correlated with seizure reduction rate in alpha, beta, and theta frequency bands in weighted adjacency matrices with densities of 90%. We conclude that KDTs tended to modify minor-to-moderate-intensity brain connections; the reduction of global connectivity and the increment of betweenness centrality after six months of KDTs were associated with better KD effectiveness.
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Helander, P., and M. Lisak. "Effects of trapped alpha particles on internal kink modes in tokamaks." Journal of Plasma Physics 47, no. 2 (1992): 281–93. http://dx.doi.org/10.1017/s0022377800024235.
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The theory of linear interaction between internal kink modes and fusionproduced high-energy alpha particles in a toroidal plasma is extended by including finite-banana-width corrections to the alpha dynamics. An important implication of the theory for the stability properties of kink modes is that the finite-banana-width effects increase the value of the poloidal alpha beta required to attain the stable domain of operation as well as that required to excite the high-frequency fishbone instability. Furthermore, these effects lead to a reduction in the instability growth rate in both the low- and high-frequency unstable regimes.
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SILES, VINCENT, and HUGO HERBELIN. "Pure Type System conversion is always typable." Journal of Functional Programming 22, no. 2 (2012): 153–80. http://dx.doi.org/10.1017/s0956796812000044.
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AbstractPure Type Systems are usually described in two different ways, one that uses an external notion of computation like beta-reduction, and one that relies on a typed judgment of equality, directly in the typing system. For a long time, the question was open to know whether both presentations described the same theory. A first step towards this equivalence has been made by Adams for a particular class ofPure Type Systems(PTS) called functional. Then, his result has been relaxed to all semi-full PTSs in previous work. In this paper, we finally give a positive answer to the general question, and prove that equivalence holds for any Pure Type System.
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Nielsen, Jørgen. "The distribution of volume reductions induced by isotropic random projections." Advances in Applied Probability 31, no. 04 (1999): 985–94. http://dx.doi.org/10.1017/s0001867800009563.
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In this paper, isotropic random projections of d-sets in ℝ n are studied, where a d-set is a subset of a d-dimensional affine subspace which satisfies certain regularity conditions. The squared volume reduction induced by the projection of a d-set onto an isotropic random p-subspace is shown to be distributed as a product of independent beta-distributed random variables, for d ≤ p. One of the proofs of this result uses Wilks' lambda distribution from multivariate normal theory. The result is related to Cauchy's and Crofton's formulae in stochastic geometry. In particular, it can be used to give a new and quite simple proof of one of the classical Crofton intersection formulae.
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Martínez, Salomé, and Dora Salazar. "Multi-clustered solutions for a singularly perturbed forced pendulum equation." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 150, no. 1 (2019): 387–417. http://dx.doi.org/10.1017/prm.2018.62.
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AbstractIn this paper, we are concerned with unbounded solutions of the singularly perturbed forced pendulum equation in the presence of friction, namely $$\varepsilon ^2u_\varepsilon ^{{\prime}{\prime}} + \sin u_\varepsilon = \varepsilon ^2\alpha (t)u_\varepsilon + \varepsilon ^2\beta (t)u_\varepsilon ^{\prime} \quad {\rm in}\;(-L,L).{\rm }$$Using a limiting energy function, we describe the behaviour of the solutions as the parameter ε approaches zero. We also prove the existence of a family of solutions having a prescribed asymptotic profile and exhibiting a highly rotatory behaviour alternated with a highly oscillatory behaviour in some open subsets of the domain. The proof relies on a combination of the Nehari finite dimensional reduction with the topological degree theory.
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Nielsen, Jørgen. "The distribution of volume reductions induced by isotropic random projections." Advances in Applied Probability 31, no. 4 (1999): 985–94. http://dx.doi.org/10.1239/aap/1029955254.
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In this paper, isotropic random projections of d-sets in ℝn are studied, where a d-set is a subset of a d-dimensional affine subspace which satisfies certain regularity conditions. The squared volume reduction induced by the projection of a d-set onto an isotropic random p-subspace is shown to be distributed as a product of independent beta-distributed random variables, for d ≤ p. One of the proofs of this result uses Wilks' lambda distribution from multivariate normal theory. The result is related to Cauchy's and Crofton's formulae in stochastic geometry. In particular, it can be used to give a new and quite simple proof of one of the classical Crofton intersection formulae.
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Shankar, Ananth N., Arul Shankar, and Xiaoheng Wang. "Large families of elliptic curves ordered by conductor." Compositio Mathematica 157, no. 7 (2021): 1538–83. http://dx.doi.org/10.1112/s0010437x21007193.
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In this paper we study the family of elliptic curves $E/{{\mathbb {Q}}}$, having good reduction at $2$ and $3$, and whose $j$-invariants are small. Within this set of elliptic curves, we consider the following two subfamilies: first, the set of elliptic curves $E$ such that the quotient $\Delta (E)/C(E)$ of the discriminant divided by the conductor is squarefree; and second, the set of elliptic curves $E$ such that the Szpiro quotient$\beta _E:=\log |\Delta (E)|/\log (C(E))$ is less than $7/4$. Both these families are conjectured to contain a positive proportion of elliptic curves, when ordered by conductor. Our main results determine asymptotics for both these families, when ordered by conductor. Moreover, we prove that the average size of the $2$-Selmer groups of elliptic curves in the first family, again when these curves are ordered by their conductors, is $3$. The key new ingredients necessary for the proofs are ‘uniformity estimates’, namely upper bounds on the number of elliptic curves with bounded height, whose discriminants are divisible by high powers of primes.
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Armand, Ella Fils, Manjula Shantaram, Njayou Frédéric Nico, Fewou Ngamli Simon, and Moundipa Fewou Paul. "Potential of medicinal plant compounds to targeting Tau protein in the therapy of Alzheimer’s disease– A review." Biomedicine 39, no. 2 (2020): 217–27. http://dx.doi.org/10.51248/.v39i2.184.
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Alzheimer’s disease (AD) is a devastative neurodegenerative disorder with complex etiology. AD is characterized by blood-brain barrier disruption, oxidative stress, mitochondrial impairment, neuro- inflammation, hypo-metabolism; it decreases in acetylcholine levels and a reduction of cerebral blood flow. It is also not solely the end-product of aberrantly processed, misfolded, and aggregated oligomeric amyloid- beta peptides but hyper phosphorylated Tau (tubulin binding protein) which formed senile plaque and intracellular neurofibrillary tangles respectively. However, despite the long-term and worldwide effort for a more effective therapy, the only available treatment is a symptomatic use of acetylcholinesterase inhibitors and memantine. Then, many researchers focused their attention to modulate amyloid-beta peptides. These therapeutic approaches as well as those based on cholinergic or amyloid theory have not brought the desired benefits yet. Thus, the main features related with the Tau pathology found in AD are Tau phosphorylation and aggregation. Based on the biochemically diverse range of pathological Tau protein, a number of approaches have been proposed to develop new potential therapeutics like inhibition of Tau phosphorylation, proteolysis and aggregation; promotion of intra- and extracellular Tau clearance and stabilization of microtubules (MTs). Medicinal plants have been used in different systems of medicine and exhibited their powerful roles in the management and cure of memory disorders. This review paper discusses the potential of medicinal plant molecules to targeting Tau protein in Alzheimer’s disease therapy.
 
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Yang, Chyn-Yng, Chiung-Hua Chen, Hsin Chu, et al. "The Effect of Music Therapy on Hospitalized Psychiatric Patients’ Anxiety, Finger Temperature, and Electroencephalography." Biological Research For Nursing 14, no. 2 (2011): 197–206. http://dx.doi.org/10.1177/1099800411406258.
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Purpose: This study aimed to explore the effectiveness of music therapy in reducing anxiety in hospitalized psychiatric patients. Methodology: The authors used a randomized clinical trial design and randomly allocated the 24 enrolled participants to the experimental or the control group. Patients in the experimental group received music therapy in a therapy room at a set time for 30 min each morning for 11 days. The authors administered the Beck Anxiety Inventory (BAI) and measured skin temperature and brain waves to determine anxiety level before, during, and after music therapy. Results: Experimental group participants had lower scores on the BAI than control participants, after the music therapy ( z = −2.0, p < .05) and at 1-week follow-up ( z = −2.2, p < .05), indicating that they were experiencing significantly less anxiety. The mean BAI anxiety score fell in the experimental group from 23.9 ( SD = 9.9) at baseline to 13.9 ( SD = 8.8), after music therapy, and 12.7. ( SD = 10.5) at follow-up. The experimental group demonstrated a significant elevation in the average alpha electroencephalographic (EEG) percentage (from 38.1% to 46.7%) and a reduction in the average beta EEG percentage (from 61.9% to 53.4%) after the music therapy. After adjusting for change in patient finger temperature on the first day, mean change in finger temperature did not differ significantly between the experimental and control groups. Conclusions: Music therapy can relieve anxiety in hospitalized psychiatric patients and help them achieve a state of relaxation.
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Mukherjee, Swarnajay, and Kausik Sarkar. "Effects of matrix viscoelasticity on the lateral migration of a deformable drop in a wall-bounded shear." Journal of Fluid Mechanics 727 (June 21, 2013): 318–45. http://dx.doi.org/10.1017/jfm.2013.251.
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AbstractThe dynamics of a drop deforming, orienting and moving in a shear flow of a viscoelastic liquid near a wall is numerically investigated using a front-tracking finite-difference method and a semi-analytic theory. The viscoelasticity is modelled using the modified FENE-CR constitutive equation. In a Newtonian system, deformation in a drop breaks the reversal symmetry of the system resulting in a migration away from the wall. This study shows that the matrix elasticity reduces the migration velocity, the reduction scaling approximately linearly with viscoelasticity (product of the Deborah numberDeand the ratio of polymer viscosity to total viscosity$\beta $). Similar to a Newtonian system, for small Deborah numbers, the dynamics quickly reaches a quasi-steady state where deformation, inclination, as well as migration and slip velocities become independent of the initial drop–wall separation. They all approximately scale inversely with the square of the instantaneous separation except for deformation which scales inversely with the cube of separation. The deformation shows a non-monotonic variation with increasing viscoelasticity similar to the case of a drop in an unbounded shear and is found to influence little the change in migration. Two competing effects due to matrix viscoelasticity on drop migration are identified. The first stems from the reduced inclination angle of the drop with increasing viscoelasticity that tries to enhance migration velocity. However, it is overcome by the second effect inhibiting migration that results from the normal stress differences from the curved streamlines around the drop; they are more curved on the side away from the wall compared with those in the gap between the wall and the drop, an effect that is also present for a rigid particle. A perturbative theory of migration is developed for small ratio of the drop size to its separation from the wall that clearly shows the migration to be caused by the image stresslet field due to the drop in presence of the wall. The theory delineates the two competing viscoelastic effects, their relative magnitudes, and predicts migration that matches well with the simulation. Using the simulation results and the stresslet theory, we develop an algebraic expression for the quasi-steady migration velocity as a function ofCa,Deand$\beta $. The transient dynamics of the migrating drop is seen to be governed by the finite time needed for development of the viscoelastic stresses. For larger capillary numbers, in both Newtonian and viscoelastic matrices, a viscous drop fails to reach a quasi-steady state independent of initial drop–wall separation. Matrix viscoelasticity tends to prevent drop breakup. Drops that break up in a Newtonian matrix are stabilized in a viscoelastic matrix if it is initially far away from the wall. Initial proximity to the wall enhances deformation and aids in drop breakup.
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BALDAN, PAOLO, CLARA BERTOLISSI, HORATIU CIRSTEA, and CLAUDE KIRCHNER. "A rewriting calculus for cyclic higher-order term graphs." Mathematical Structures in Computer Science 17, no. 3 (2007): 363–406. http://dx.doi.org/10.1017/s0960129507006093.
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The Rewriting Calculus (ρ-calculus, for short) was introduced at the end of the 1990s and fully integrates term-rewriting and λ-calculus. The rewrite rules, acting as elaborated abstractions, their application and the structured results obtained are first class objects of the calculus. The evaluation mechanism, which is a generalisation of beta-reduction, relies strongly on term matching in various theories.In this paper we propose an extension of the ρ-calculus, called ρg-calculus, that handles structures with cycles and sharing rather than simple terms. This is obtained by using recursion constraints in addition to the standard ρ-calculus matching constraints, which leads to a term-graph representation in an equational style. Like in the ρ-calculus, the transformations are performed by explicit application of rewrite rules as first-class entities. The possibility of expressing sharing and cycles allows one to represent and compute over regular infinite entities.We show that the ρg-calculus, under suitable linearity conditions, is confluent. The proof of this result is quite elaborate, due to the non-termination of the system and the fact that ρg-calculus-terms are considered modulo an equational theory. We also show that the ρg-calculus is expressive enough to simulate first-order (equational) left-linear term-graph rewriting and α-calculus with explicit recursion (modelled using a letrec-like construct).
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Hanušová, J., M. Mihulová, L. Diblíková, and L. Čurda. "Influence of salts on selective coagulation of whey proteins and their application in the isolation of β-lactoglobulin." Czech Journal of Food Sciences 32, No. 1 (2014): 77–81. http://dx.doi.org/10.17221/524/2012-cjfs.
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Whey proteins are an important constituent of milk, especially whey from cheese manufacture and have many valuable functional properties such as foaming and emulsifying ability or gel formation. Some whey proteins are sensitive to salt content in a solution. High or low salt content may lead to selective coagulation of these proteins. A part of whey proteins was precipitated by addition of 7% (wt) NaCl and &beta;-lactoglobulin and caseinomacropeptide remained in the supernatant. It was necessary to demineralise the supernatant by electrodialysis for the selective coagulation of caseinomacropeptide from this material. Subsequently, ethanol was added and pH was adjusted. This reduction of the ionic strength and the addition of ethanol induced the selective precipitation of caseinomacropeptide (91.4% from the original amount of CMP). &beta;-lactoglobulin of 91% purity remained in the solution. &nbsp;
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Karpova, Darja, Michael P. Rettig, Linda Eissenberg, et al. "Combined Targeting of CXCR2 and VLA4 Results in Rapid and Synergistic Mobilization of Hematopoietic Stem and Progenitor Cells in Mice." Blood 128, no. 22 (2016): 659. http://dx.doi.org/10.1182/blood.v128.22.659.659.
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Abstract Introduction : Since the first description of hematopoietic stem and progenitor cell (HSPC) mobilization over forty years ago, it has become the standard of care for both autologous and allogeneic transplantation. A five-day course of G-CSF represents the most commonly used mobilization regimen today. The CXCR4 inhibitor, plerixafor, is a more rapid but weak mobilizer when used as a single agent, thus emphasizing the need for faster acting agents with more predictable mobilization responses and fewer side effects. Methods : Given the critical role of VLA4/VCAM1 signaling for migration and retention of HSPC, we were seeking to identify small molecule antagonists of VLA4 with improved potency and bioavailability. Relative to previously described comparators Bio5192 (▢4▢1-specific) and firategrast (▢4▢1 and ▢4▢7 dual-specific), our lead candidate, CWHM-823, exhibited increased aqueous solubility and ~10-100 fold better activity in blocking VLA4 and mobilizing HSPC in mice. CWHM-823 pharmacokinetics and mobilization were assessed in BALB/c and DBA/2 mice at different doses (3 to 15 mg/kg) and time points (15 to 240 min) when administered alone or in combination with the truncated isoform of the CXCR2 agonist Gro-beta (tGro-β, 2.5 mg/kg, generously provided by GlaxoSmithKline). HSPC mobilization was monitored using flow cytometry and clonogenic in vitro assays. "True" stem cells were measured in a serial competitive transplantation assay. The combination of tGro-β and VLA4 antagonist was further tested in diabetic mice in comparison to G-CSF (9 x 100μg/kg, q12h). RNA profiling of flow-sorted HSPC was performed via microarray analysis. Results : The combination of tGro-β with each VLA4 antagonist resulted in a dramatic synergistic increase in circulating HSPC numbers when compared to steady state (50-70-fold) or treatment with single agents (3-10 fold) including tGroβ. Mobilization with tGro-β + CWHM-823 was rapid, peaking at 15-30 minutes after injection. In a model of streptozotocin-induced diabetes, the mobilopathy (reduction in stem cell mobilization compared to wild type mice) was considerably less pronounced with the combination tGro-β + CWHM-823 (~1.5-fold lower CFU mobilization in diabetic mice) versus the 5-day course of G-CSF (~3-fold reduction). Despite the superior progenitor cell mobilization achieved with G-CSF (~2-fold more CFU and LSK/ml), the concentration of serially repopulating units (RU) was equally high in the tGro-β + CWHM-823 and G-CSF mobilized grafts suggesting a higher HSC frequency (1 RU out of 200 vs. 1 RU out of 400 LSK/CFU) in the tGro-β + CWHM-823 mobilized grafts (Figure 1). RNA profiling demonstrated close similarity between the expression profile of tGro-β + CWHM-823 mobilized, BM resident, and G-CSF mobilized LSK, with less than 0.5% of genes found to be significantly up- or downregulated. CXCR2 chemokine receptor stimulation was critical for the observed synergistic response, as pretreatment ("priming") or simultaneous treatment with tGro-β resulted in subsequent enhanced mobilization using VLA4 inhibitors, whereas reversed administration (VLA4 antagonist followed by tGro-β) had no effect on potency of either agent. Lack of surface CXCR2 expression on HSPC suggested that a rapidly acting effector molecule released from tGro-β-stimulated mature myeloid cells may subsequently influence VLA4-mediated HSPC adhesion/retention. Consistent with this theory, we observed increased protease MMP-9 in plasma within minutes after treatment with tGro-β + CWHM-823. Conclusions: We describe a novel strategy for rapid, reliable, and potent mobilization of HSPC in mice using a combination of VLA4 blockade (via novel and potent ▢4▢1 inhibitors) and CXCR2 activation (via tGro-β). The combination of tGro-β + VLA4 inhibitors or tGro-β followed by VLA4 inhibitors results in synergistic and rapid HSPC mobilization with quantity and quality of repopulating units similar to optimal mobilization with G-CSF. These data suggest further development of tGro-β + VLA4 inhibitor combinations for clinical testing is warranted. Figure 1. Mobilization of repopulating units (RU) (n=8-10 recipients per group, mean±SEM) Figure 1. Mobilization of repopulating units (RU) (n=8-10 recipients per group, mean±SEM) Disclosures No relevant conflicts of interest to declare.
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McKinna, James, and Robert Pollack. "Some Lambda Calculus and Type Theory Formalized." BRICS Report Series 4, no. 51 (1997). http://dx.doi.org/10.7146/brics.v4i51.19272.
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"This paper is about our hobby." That is the first sentence of [MP93], the first report on our formal development of lambda calculus and type theory, written in autumn 1992. We have continued to pursue this hobby on and off ever since, and have developed a substantial body of formal knowledge, including Church-Rosser and standardization<br />theorems for beta reduction, and the basic theory of<br />Pure Type Systems (PTS) leading to the strengthening theorem and type checking algorithms for PTS. Some of this work is reported in [MP93, vBJMP94, Pol94b, Pol95]. In the present paper we survey this work, including some new proofs, and point out what we feel has been learned about the general issues of formalizing mathematics. On the technical side, we describe an abstract, and simplified, proof of standardization for beta reduction, not previously published, that does<br />not mention redex positions or residuals. On the general issues, we emphasize the search for formal definitions that are convenient for formal proof and convincingly represent the intended informal concepts. The LEGO Proof Development System [LP92] was used to check the work in an implementation of the Extended Calculus of Constructions<br />(ECC) with inductive types [Luo94]. LEGO is a refinement style<br />proof checker, publicly available by ftp and WWW, with a User's Manual [LP92] and a large collection of examples. Section 1.3 contains information on accessing the formal development described in this paper. Other interesting examples formalized in LEGO include program specification and data refinement [Luo91], strong normalization of System F [Alt93], synthetic domain theory [Reu95, Reu96], and operational semantics for imperative programs [Sch97].
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Restuccia, Alvaro, and Francisco Tello-Ortiz. "Pure electromagnetic-gravitational interaction in Hořava–Lifshitz theory at the kinetic conformal point." European Physical Journal C 80, no. 2 (2020). http://dx.doi.org/10.1140/epjc/s10052-020-7674-7.
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Abstract We introduce the electromagnetic-gravitational coupling in the Hořava–Lifshitz framework, in $$3+1$$3+1 dimensions, by considering the Hořava–Lifshitz gravity theory in $$4+1$$4+1 dimensions at the kinetic conformal point and then performing a Kaluza–Klein reduction to $$3+1$$3+1 dimensions. The action of the theory is second order in time derivatives and the potential contains only higher order spacelike derivatives up to $$z=4$$z=4, z being the critical exponent. These terms include also higher order derivative terms of the electromagnetic field. The propagating degrees of freedom of the theory are exactly the same as in the Einstein–Maxwell theory. We obtain the Hamiltonian, the field equations and show consistency of the constraint system. The conformal kinetic point is protected from quantum corrections by a second class constraint. At low energies the theory depends on two coupling constants, $$\beta $$β and $$\alpha $$α. We show that the anisotropic field equations for the gauge vector is a deviation of the covariant Maxwell equations by a term depending on $$\beta -1$$β-1. Consequently, for $$\beta =1$$β=1, Maxwell equations arise from the anisotropic theory at low energies. We also prove that the anisotropic electromagnetic-gravitational theory at the IR point $$\beta =1$$β=1, $$\alpha =0$$α=0, is exactly the Einstein–Maxwell theory in a gravitational gauge used in the ADM formulation of General Relativity.
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Zhang, Tao, Fu-Wen Shu, Qing-Wen Tang, and Dong-Hui Du. "Constraints on Hořava–Lifshitz gravity from GRB 170817A." European Physical Journal C 80, no. 11 (2020). http://dx.doi.org/10.1140/epjc/s10052-020-08626-z.
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AbstractIn this work we focus on a toy model: ($$3+1$$ 3 + 1 )-dimensional Hořava–Lifshitz gravity coupling with an anisotropic electromagnetic (EM) field which is generated through a Kaluza-Klein reduction of a ($$4+1$$ 4 + 1 )-dimensional Hořava–Lifshitz gravity. This model exhibits a remarkable feature that it has the same velocity for both gravitational and electromagnetic waves. This feature makes it possible to restrict the parameters of the theory from GRB 170817A. In this work we use this feature to discuss possible constraints on the parameter $$\beta $$ β in the theory, by analyzing the possible Lorentz invariance violation effect of the GRB 170817A. This is achieved by analyzing potential time delay of gamma-ray photons in this event. It turns out that it places a stringent constraint on this parameter. In the most ideal case, it gives $$|1-\sqrt{\beta }|<(10^{-19}-10^{-18})$$ | 1 - β | < ( 10 - 19 - 10 - 18 ) .
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Chapman, Shira, Lorenzo Di Pietro, Kevin T. Grosvenor, and Ziqi Yan. "Renormalization of Galilean electrodynamics." Journal of High Energy Physics 2020, no. 10 (2020). http://dx.doi.org/10.1007/jhep10(2020)195.
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Abstract We study the quantum properties of a Galilean-invariant abelian gauge theory coupled to a Schrödinger scalar in 2+1 dimensions. At the classical level, the theory with minimal coupling is obtained from a null-reduction of relativistic Maxwell theory coupled to a complex scalar field in 3+1 dimensions and is closely related to the Galilean electromagnetism of Le-Bellac and Lévy-Leblond. Due to the presence of a dimensionless, gauge-invariant scalar field in the Galilean multiplet of the gauge-field, we find that at the quantum level an infinite number of couplings is generated. We explain how to handle the quantum corrections systematically using the background field method. Due to a non-renormalization theorem, the beta function of the gauge coupling is found to vanish to all orders in perturbation theory, leading to a continuous family of fixed points where the non-relativistic conformal symmetry is preserved.
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Libby, Peter. "Inflammation in Atherosclerosis—No Longer a Theory." Clinical Chemistry, January 4, 2021. http://dx.doi.org/10.1093/clinchem/hvaa275.
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Abstract Background Inflammation links to atherosclerosis and its complications in various experimental investigations. Animal studies have implicated numerous inflammatory mediators in the initiation and complication of atherosclerosis. Numerous studies in humans have shown associations of biomarkers of inflammation with cardiovascular events provoked by atheromata. Inflammatory status, determined by the biomarker C-reactive protein, can guide the allocation of statin therapy to individuals without elevated low-density lipoprotein (LDL) concentrations to prevent first ever adverse cardiovascular events. Content Until recently, no direct evidence has shown that an intervention that selectively limits inflammation can improve outcomes in patients with atherosclerosis. A recent study, based on decades of preclinical investigation, treated patients who had sustained a myocardial infarction and whose LDL was well-controlled on statin treatment with an antibody that neutralizes interleukin-1 beta. This trial, conducted in over 10 000 individuals, showed a reduction in major adverse cardiac events, establishing for the first time the clinical efficacy of an anti-inflammatory intervention in atherosclerosis. Two large subsequent studies have shown that colchicine treatment can also prevent recurrent events in patients recovering from an acute coronary syndrome or in the stable phase of coronary artery disease. These clinical trials have transformed inflammation in atherosclerosis from theory to practice. Summary Much work remains to optimize further anti-inflammatory interventions, minimize unwanted actions, and refine patient selection. This long road from discovery in the laboratory to successful clinical trials represents a victory for medical science, and opens a new avenue to reducing the risk that remains despite current treatments for atherosclerosis.
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Gallegos, A. D., U. Gürsoy, and N. Zinnato. "Torsional Newton Cartan gravity from non-relativistic strings." Journal of High Energy Physics 2020, no. 9 (2020). http://dx.doi.org/10.1007/jhep09(2020)172.
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Abstract We study propagation of closed bosonic strings in torsional Newton-Cartan geometry based on a recently proposed Polyakov type action derived by dimensional reduction of the ordinary bosonic string along a null direction. We generalize the Polyakov action proposal to include matter, i.e. the 2-form and the 1-form that originates from the Kalb- Ramond field and the dilaton. We determine the conditions for Weyl invariance which we express as the beta-function equations on the worldsheet, in analogy with the usual case of strings propagating on a pseudo-Riemannian manifold. The critical dimension of the TNC space-time turns out to be 25. We find that Newton’s law of gravitation follows from the requirement of quantum Weyl invariance in the absence of torsion. Presence of the 1-form requires torsion to be non vanishing. Torsion has interesting consequences, in particular it yields a mass term and an advection term in the generalized Newton’s law. U(1) mass invariance of the theory is an important ingredient in deriving the beta functions.
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Mirzaei-Alavijeh, Mehdi, Cyrus Jalili, Pedram Rezaei-Zadeh, and Farzad Jalilian. "Socio-cognitive Determinants of Plagiarism Intention Among Kermanshah University of Medical Sciences Students: A Cross-sectional Study in 2018." Iranian Journal of Psychiatry and Behavioral Sciences 15, no. 1 (2021). http://dx.doi.org/10.5812/ijpbs.83796.
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Background: Plagiarism is one of the most common and important misconducts in the educational and research environment. Plagiarism means transcribing the works or ideas of others without authenticating the source and the original author and assigning them to self. Objectives: The current research aimed to investigate the socio-cognitive constructs associated with plagiarism among Kermanshah University of Medical Sciences (KUMS) students using the theory of planned behavior (TPB). Methods: This cross-sectional study was done at KUMS, the west of Iran, among 231 medical university students in 2018, which were selected randomly to participate voluntarily. Students filled out a self-report questionnaire that included the demographics and TPB variables. Data gathered were analyzed by the Statistical Package for Social Sciences (version 16) using a t-test, Pearson correlation, and linear regression. Results: The determinants of attitude, subjective norms (SN), and perceived behavioral control (PBC) accounted for 15% of behavioral intention (BI) to plagiarism. Linear regression showed that SN (beta = 0.229; P = 0.001) and PBC (beta = -0.217; P = 0.001) were the most influential predictors of plagiarism intention. Conclusions: According to the result, it seems that planning programs to increase perceived behavioral control against doing plagiarism and reduce subjective norms encouraging plagiarism may be useful for the prevention and reduction of plagiarism among university students.
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Mitchell, William, Srinivas Marmamula, Nazlee Zebardast, et al. "Psychometric validation techniques applied to the IND-VFQ-33 visual function questionnaire: the Hyderabad ocular morbidity in the elderly study (HOMES)." BMC Medical Research Methodology 21, no. 1 (2021). http://dx.doi.org/10.1186/s12874-021-01217-w.
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Abstract Background Over 2 billion people suffer from vision impairment or blindness globally, and access to validated visual measurement tools in imperative in accurately describing and managing the burden of eye disease. The present study applies contemporary psychometric validation techniques to the widely used 33-item Indian Visual Function Questionnaire (IND-VFQ-33). Methods We first estimated the polychoric correlation between each pair of items. Next, an unrotated and oblique Promax rotated factor analysis, item response theory (IRT, using a graded response model (GRM)), and differential item functioning (DIF) testing were applied to the IND-VFQ-33. We subsequently propose a validated IND-VFQ-33 questionnaire after psychometric testing, data reduction, and adjustment. Results Exploratory unrotated factor analysis identified two factors; one with a particularly high eigenvalue (18.1) and a second with a lower eigenvalue still above our threshold (1.1). A subsequent oblique Promax factor rotation was undertaken for a 2-factor solution, revealing two moderately correlated factors (+ 0.68) with clinically discrete item loadings onto either Factor 1 (21 items; collectively labelled “daily activities”) or Factor 2 (5 items; collectively labelled “bright lights”). IRT confirmed high item discrimination for all remaining items with good separation between difficulty thresholds. We found significant DIF on depression for six items in Factor 1 (all uniform DIF, except item 21 (non-uniform DIF) with no substantive difference in beta thresholds for any item and no substantive difference in expected individual or sum score, by depression at baseline. For Factor 2, only one item demonstrated significant uniform DIF on gender, similarly without major differences in beta thresholds or expected total score between gender at baseline. Consequently, no further item recalibration or reduction was undertaken after IRT and DIF analysis. Conclusion Applying IRT and DIF validation techniques to the IND-VFQ-33 identified 2 discrete factors with 26 uniquely-loading items, clinically representative of difficulty performing daily activities and experiencing difficulty due to bright lights/glare respectively. The proposed modified scale may be useful in evaluating symptomatic disease progression or response to treatment in an Indian population.
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Chen, Xiaoping, Bernhard Kretz, Francis Adoah, et al. "A single atom change turns insulating saturated wires into molecular conductors." Nature Communications 12, no. 1 (2021). http://dx.doi.org/10.1038/s41467-021-23528-8.
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AbstractWe present an efficient strategy to modulate tunnelling in molecular junctions by changing the tunnelling decay coefficient, β, by terminal-atom substitution which avoids altering the molecular backbone. By varying X = H, F, Cl, Br, I in junctions with S(CH2)(10-18)X, current densities (J) increase >4 orders of magnitude, creating molecular conductors via reduction of β from 0.75 to 0.25 Å−1. Impedance measurements show tripled dielectric constants (εr) with X = I, reduced HOMO-LUMO gaps and tunnelling-barrier heights, and 5-times reduced contact resistance. These effects alone cannot explain the large change in β. Density-functional theory shows highly localized, X-dependent potential drops at the S(CH2)nX//electrode interface that modifies the tunnelling barrier shape. Commonly-used tunnelling models neglect localized potential drops and changes in εr. Here, we demonstrate experimentally that $$\beta \propto 1/\sqrt{{\varepsilon }_{r}}$$ β ∝ 1 / ε r , suggesting highly-polarizable terminal-atoms act as charge traps and highlighting the need for new charge transport models that account for dielectric effects in molecular tunnelling junctions.
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Gregg, Robert W., Fathima Shabnam та Jason E. Shoemaker. "Agent-based modeling reveals benefits of heterogeneous and stochastic cell populations during cGAS-mediated IFNβ production". Bioinformatics, 16 листопада 2020. http://dx.doi.org/10.1093/bioinformatics/btaa969.
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Abstract Motivation The cGAS pathway is a component of the innate immune system responsible for the detection of pathogenic DNA and upregulation of interferon beta (IFNβ). Experimental evidence shows that IFNβ signaling occurs in highly heterogeneous cells and is stochastic in nature; however, the benefits of these attributes remain unclear. To investigate how stochasticity and heterogeneity affect IFNβ production, an agent-based model is developed to simulate both DNA transfection and viral infection. Results We show that heterogeneity can enhance IFNβ responses during infection. Furthermore, by varying the degree of IFNβ stochasticity, we find that only a percentage of cells (20–30%) need to respond during infection. Going beyond this range provides no additional protection against cell death or reduction of viral load. Overall, these simulations suggest that heterogeneity and stochasticity are important for moderating immune potency while minimizing cell death during infection. Availability and implementation Model repository is available at: https://github.com/ImmuSystems-Lab/AgentBasedModel-cGASPathway. Contact jason.shoemaker@pitt.edu Supplementary information Supplementary data are available at Bioinformatics online.
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Moya, Pablo S., and Roberto E. Navarro. "Effects of the Background Turbulence on the Relaxation of Ion Temperature Anisotropy in Space Plasmas." Frontiers in Physics 9 (April 14, 2021). http://dx.doi.org/10.3389/fphy.2021.624748.
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Turbulence in space plasmas usually exhibits two regimes separated by a spectral break that divides the so called inertial and kinetic ranges. Large scale magnetic fluctuations are dominated by non-linear MHD wave-wave interactions following a −5/3 or −2 slope power-law spectrum. After the break, at scales in which kinetic effects take place, the magnetic spectrum follows a steeper power-law k−α shape given by a spectral index α &gt; 5/3. Despite its ubiquitousness, the possible effects of a turbulent background spectrum in the quasilinear relaxation of solar wind temperatures are usually not considered. In this work, a quasilinear kinetic theory is used to study the evolution of the proton temperatures in an initially turbulent collisionless plasma composed by cold electrons and bi-Maxwellian protons, in which electromagnetic waves propagate along a background magnetic field. Four wave spectrum shapes are compared with different levels of wave intensity. We show that a sufficient turbulent magnetic power can drive stable protons to transverse heating, resulting in an increase in the temperature anisotropy and the reduction of the parallel proton beta. Thus, stable proton velocity distribution can evolve in such a way as to develop kinetic instabilities. This may explain why the constituents of the solar wind can be observed far from thermodynamic equilibrium and near the instability thresholds.
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Alm, Per A. "Stuttering: A Disorder of Energy Supply to Neurons?" Frontiers in Human Neuroscience 15 (August 26, 2021). http://dx.doi.org/10.3389/fnhum.2021.662204.
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Stuttering is a disorder characterized by intermittent loss of volitional control of speech movements. This hypothesis and theory article focuses on the proposal that stuttering may be related to an impairment of the energy supply to neurons. Findings from electroencephalography (EEG), brain imaging, genetics, and biochemistry are reviewed: (1) Analyses of the EEG spectra at rest have repeatedly reported reduced power in the beta band, which is compatible with indications of reduced metabolism. (2) Studies of the absolute level of regional cerebral blood flow (rCBF) show conflicting findings, with two studies reporting reduced rCBF in the frontal lobe, and two studies, based on a different method, reporting no group differences. This contradiction has not yet been resolved. (3) The pattern of reduction in the studies reporting reduced rCBF corresponds to the regional pattern of the glycolytic index (GI; Vaishnavi et al., 2010). High regional GI indicates high reliance on non-oxidative metabolism, i.e., glycolysis. (4) Variants of the gene ARNT2 have been associated with stuttering. This gene is primarily expressed in the brain, with a pattern roughly corresponding to the pattern of regional GI. A central function of the ARNT2 protein is to act as one part of a sensor system indicating low levels of oxygen in brain tissue and to activate appropriate responses, including activation of glycolysis. (5) It has been established that genes related to the functions of the lysosomes are implicated in some cases of stuttering. It is possible that these gene variants result in a reduced peak rate of energy supply to neurons. (6) Lastly, there are indications of interactions between the metabolic system and the dopamine system: for example, it is known that acute hypoxia results in an elevated tonic level of dopamine in the synapses. Will mild chronic limitations of energy supply also result in elevated levels of dopamine? The indications of such interaction effects suggest that the metabolic theory of stuttering should be explored in parallel with the exploration of the dopaminergic theory.
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Roy, Abhrajeet V., Michelle Thai, Bonnie Klimes-Dougan, et al. "Brain entropy and neurotrophic molecular markers accompanying clinical improvement after ketamine: Preliminary evidence in adolescents with treatment-resistant depression." Journal of Psychopharmacology, July 9, 2020, 026988112092820. http://dx.doi.org/10.1177/0269881120928203.
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Background: Current theory suggests that treatment-resistant depression (TRD) involves impaired neuroplasticity resulting in cognitive and neural rigidity, and that clinical improvement may require increasing brain flexibility and adaptability. Aims: In this hypothesis-generating study, we sought to identify preliminary evidence of brain flexibility correlates of clinical change within the context of an open-label ketamine trial in adolescents with TRD, focusing on two promising candidate markers of neural flexibility: (a) entropy of resting-state functional magnetic resonance imaging (fMRI) signals; and (b) insulin-stimulated phosphorylation of mammalian target of rapamycin (mTOR) and glycogen synthase-3-beta (GSK3β) in peripheral blood mononuclear cells. Methods: We collected resting-state functional magnetic resonance imaging data and blood samples from 13 adolescents with TRD before and after a series of six ketamine infusions over 2 weeks. Usable pre/post ketamine data were available from 11 adolescents for imaging and from 10 adolescents for molecular signaling. We examined correlations between treatment response and changes in the central and peripheral flexibility markers. Results: Depression reduction correlated with increased nucleus accumbens entropy. Follow-up analyses suggested that physiological changes were associated with treatment response. In contrast to treatment non-responders ( n=6), responders ( n=5) showed greater increase in nucleus accumbens entropy after ketamine, together with greater post-treatment insulin/mTOR/GSK3β signaling. Conclusions: These data provide preliminary evidence that changes in neural flexibility may underlie symptom relief in adolescents with TRD following ketamine. Future research with adequately powered samples is needed to confirm resting-state entropy and insulin-stimulated mTOR and GSK3β as brain flexibility markers and candidate targets for future clinical trials. Clinical trial name: Ketamine in adolescents with treatment-resistant depression URL: https://clinicaltrials.gov/ct2/show/NCT02078817 Registration number: NCT02078817
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Lorthe, Elsa, Gilles Kayem, Gilles Kayem, et al. "Tocolysis in the management of preterm prelabor rupture of membranes at 22–33 weeks of gestation: study protocol for a multicenter, double-blind, randomized controlled trial comparing nifedipine with placebo (TOCOPROM)." BMC Pregnancy and Childbirth 21, no. 1 (2021). http://dx.doi.org/10.1186/s12884-021-04047-2.
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Abstract Background Preterm prelabor rupture of membranes (PPROM) before 34 weeks of gestation complicates 1% of pregnancies and accounts for one-third of preterm births. International guidelines recommend expectant management, along with antenatal steroids before 34 weeks and antibiotics. Up-to-date evidence about the risks and benefits of administering tocolysis after PPROM, however, is lacking. In theory, reducing uterine contractility could delay delivery and reduce the risks of prematurity and its adverse short- and long-term consequences, but it might also prolong fetal exposure to inflammation, infection, and acute obstetric complications, potentially associated with neonatal death or long-term sequelae. The primary objective of this study is to assess whether short-term (48 h) tocolysis reduces perinatal mortality/morbidity in PPROM at 22 to 33 completed weeks of gestation. Methods A randomized, double-blind, placebo-controlled, superiority trial will be performed in 29 French maternity units. Women with PPROM between 220/7 and 336/7 weeks of gestation, a singleton pregnancy, and no condition contraindicating expectant management will be randomized to receive a 48-hour oral treatment by either nifedipine or placebo (1:1 ratio). The primary outcome will be the occurrence of perinatal mortality/morbidity, a composite outcome including fetal death, neonatal death, or severe neonatal morbidity before discharge. If we assume an alpha-risk of 0.05 and beta-risk of 0.20 (i.e., a statistical power of 80%), 702 women (351 per arm) are required to show a reduction of the primary endpoint from 35% (placebo group) to 25% (nifedipine group). We plan to increase the required number of subjects by 20%, to replace any patients who leave the study early. The total number of subjects required is thus 850. Data will be analyzed by the intention-to-treat principle. Discussion This trial will inform practices and policies worldwide. Optimized prenatal management to improve the prognosis of infants born preterm could benefit about 50,000 women in the European Union and 40,000 in the United States each year. Trial registration ClinicalTrials.gov identifier: NCT03976063 (registration date June 5, 2019).