bluuebunny/crossref_metadata_2025 huggingface dataset:
Epigenetics and DNA methylomic profiling in Alzheimer's disease and other neurodegenerative diseases
Authors: Roubroeks Janou A. Y. , Smith Rebecca G. , van den Hove Daniel L. A. , Lunnon Katie
Published: August 2017

Recent studies have suggested a role for epigenetic mechanisms in the complex etiology of various neurodegenerative diseases. In this review, we discuss advances that have been made toward understanding the role of epigenetic processes in neurodegenerative disorders, with a particular focus on Alzheimer's disease, where the most extensive studies have been undertaken to date. We provide a brief overview of DNA modifications, followed by a summarization of studies of DNA modifications in Alzheimer's disease and other neurodegenerative diseases.

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Farmworker Vulnerability to Heat Hazards: A Conceptual Framework
Authors: Mac Valerie Vi Thien , McCauley Linda A.
Published: August 2017

Purpose

To review factors that impact the effect of hot environments on the human body in order to develop a conceptual model of human biological response.

Methods

The organizing concept for the model development was the multilevel integration of three major factors, exposure to heat, sensitivity and adaptive capacity, and the heat stress response. Exposure of a vulnerable occupational group was used to illustrate the components of the model.

Findings

Components of this framework include the hazard (environmental heat stress), vulnerability factors (workplace exposure, sensitivity and adaptive capacity), and the heat stress response. The combination of the vulnerability factors of workplace exposure (work intensity, duration), sensitivity (age, gender, etc.), and adaptive capacity (hydration, clothing, work hygiene) mediate a worker's heat stress response to the hazard. A worker's heat stress response can be classified as progressing towards two outcomes: physiologic equilibrium or physiologic disequilibrium.

Conclusions

This framework provides a starting point for the design and development of studies of heat‐related illness (HRI) in farmworker and other vulnerable populations exposed to rising global temperatures.

Clinical Relevance

Identification of vulnerability factors to HRI, informs research designs which will lead to the development of public health interventions.
Friends You Can Trust: A Signaling Theory of Interest Group Litigation Before the U.S. Supreme Court
Authors: Manzi Lucia , Hall Matthew E.K.
Published: August 2017

How do interest groups influence U.S. Supreme Court justices to vote in favor of their preferred outcomes? Following prior research on the influence of the Solicitor General, we develop and expand on the signaling theory of interest group influence via amicus curie briefs. We argue that an interest group's ideological reputation and the nature of the ideological signal it sends in its brief both function as powerful heuristics that convey information to the justices depending on the justices' own ideological preferences. When an organization files an amicus brief advocating for an outcome seemingly contrary to its traditional preferences (i.e., an unexpected signal), this signal should be more noticeable and credible than a signal in accordance with a group's conventional views (i.e., an expected signal). However, unexpected signals should have greater influence on justices who share the brief filer's preferences. We test our signaling theory on the terms from 1991 through 2002. We find that unexpected signals (but not expected signals) are associated with Supreme Court voting, and the influence of unexpected signals appears to be particularly strong among justices who share the ideological preferences of the brief filer.
The threat of invasive species to bats: a review
Authors: Welch Jessica Nicole , Leppanen Christy
Published: August 2017

Biological invasions are a major driver of biodiversity loss, but no study has described the scope of threats to bats (Chiroptera) by invasive species.

We reviewed the literature for negative effects of invasive species to bats and summarised threats according to four categories: predation, disease, competition, and indirect interactions. We identified threats of 37 invasive species to 40 bat species. Ten bat species were threatened by more than one invasion pathway.

About 38 percent of cases are speculative and 18 percent circumstantial, many attributed to overlapping ranges, and most accounts do not quantify effects needed to forecast bat population impacts.

Evidence of cat predation is frequently cited, constituting the greatest incidence of observational data. Other direct and indirect impacts were documented from goats, dogs, brown tree snake, rainbow lorikeet, rose‐ringed parakeet, yellow crazy ant, giant centipede, palm, burdock, avian cholera, and white‐nose syndrome. Circumstantial evidence suggests impacts by rats, stoats, coqui frog, common wolf snake, little fire ant, kudzu, and Lantana camara. Other impacts by giant centipede, yellow crazy ant, cats, goats, rats, and avian cholera are speculative, as are those from pigs, deer, white eye, common starling, house sparrow, rock dove, barn and little owls, brush‐tailed possum, honeybee, wasp, phytophagous insects, tamarisk, Cinnamomum verum, and Tabebuia pallida.

Over 60 percent of bat species reviewed are island‐dwelling, corresponding with evidence indicating that most extinctions occur on islands and invasive species’ impacts are worse for island than mainland populations.

Although appreciable bat population reductions owing to invasive species are often unproven, invasions are likely to exacerbate effects of other vulnerabilities. Multiple invaders and synergistic interactions may ultimately lead to species losses.

Managers should exercise the precautionary principle by taking action against non‐native species when first detected, even if new species do not appear to be detrimental.
Contribution of early impact events to metal‐silicate separation, thermal annealing, and volatile redistribution: Evidence in the Pułtusk H chondrite
Authors: Krzesińska Agata M.
Published: August 2017

Three‐dimensional X‐ray tomographic reconstructions and petrologic studies reveal voluminous accumulations of metal in Pułtusk H chondrite. At the contact of these accumulations, the chondritic rock is enriched in troilite. The rock contains plagioclase‐rich bands, with textures suggesting crystallization from melt. Unusually large phosphates are associated with the plagioclase and consist of assemblages of merrillite, and fluorapatite and chlorapatite. The metal accumulations were formed by impact melting, rapid segregation of metal‐sulfide melt and the incorporation of this melt into the fractured crater basement. The impact most likely occurred in the early evolution of the H chondrite parent body, when post‐impact heat overlapped with radiogenic heat. This enabled slow cooling and separation of the metallic melt into metal‐rich and sulfide‐rich fractions. This led to recrystallization of chondritic rock in contact with the metal accumulations and the crystallization of shock melts. Phosphorus was liberated from the metal and subsumed by the silicate shock melt, owing to oxidative conditions upon slow cooling. The melt was also a host for volatiles. Upon further cooling, phosphorus reacted with silicates leading to the formation of merrillite, while volatiles partitioned into the residual halogen‐rich, dry fluid. In the late stages, the fluid altered merrillite to patchy Cl/F‐apatite. The above sequence of alterations demonstrates that impact during the early evolution of chondritic parent bodies might have contributed to local metal segregation and silicate melting. In addition, postshock conditions supported secondary processes: compositional/textural equilibration, redistribution of volatiles, and fluid alterations.
Fire ecology of a tree glacial refugium on a nunatak with a view on Alpine glaciers
Authors: Carcaillet Christopher , Blarquez Olivier
Published: August 2017

In paleoecology, the function of biomass as a fire driver has become a focus of attention in cold ecosystems, and concerns have been raised about climate in this context. Little is known about the fire frequency and fire–plant relationships during glaciation when woodlands were limited and the climate was cold.

Fire history and tree biomass were reconstructed from sedimentary charcoal and macroremains, respectively, archived in lake sediments from the western Alps. Two nunataks were investigated, both with lacustrine sediments covering the last 21 000 yr at least.

During the Last Glacial Maximum (LGM) and the Lateglacial, fires occurred only on the nunatak sheltering woody plants. Cembra pine (Pinus cembra) and larch (Larix decidua) survived above glaciers during the LGM, thus evidencing a biological refugium and supporting the nunatak theory.

We highlighted a long‐term relationship between fires and dominant trees over the last 21 000 yr, where fire frequencies track the global climate and the local changes in tree biomass. Glacial climate (dry, cold) does not rule out fires. Fuel load and composition were significant fire drivers, with cembra pine dominating during colder periods with rare fires, and larch during the warmer Holocene with frequent fires. These findings increase knowledge of fire ecology in cold environments, and open perspectives in tree population genetics by considering new areas of tree glacial refugia in Europe.
Medicago truncatula Molybdate Transporter type 1 (MtMOT1.3) is a plasma membrane molybdenum transporter required for nitrogenase activity in root nodules under molybdenum deficiency
Authors: Tejada‐Jiménez Manuel , Gil‐Díez Patricia , León‐Mediavilla Javier , Wen Jiangqi , Mysore Kirankumar S. , Imperial Juan , González‐Guerrero Manuel
Published: August 2017

Molybdenum, as a component of the iron‐molybdenum cofactor of nitrogenase, is essential for symbiotic nitrogen fixation. This nutrient has to be provided by the host plant through molybdate transporters.

Members of the molybdate transporter family Molybdate Transporter type 1 (MOT1) were identified in the model legume Medicago truncatula and their expression in nodules was determined. Yeast toxicity assays, confocal microscopy, and phenotypical characterization of a Transposable Element from Nicotiana tabacum (Tnt1) insertional mutant line were carried out in the one M. truncatula MOT1 family member specifically expressed in nodules.

Among the five MOT1 members present in the M. truncatula genome, MtMOT1.3 is the only one uniquely expressed in nodules. MtMOT1.3 shows molybdate transport capabilities when expressed in yeast. Immunolocalization studies revealed that MtMOT1.3 is located in the plasma membrane of nodule cells. A mot1.3‐1 knockout mutant showed impaired growth concomitant with a reduction of nitrogenase activity. This phenotype was rescued by increasing molybdate concentrations in the nutritive solution, or upon addition of an assimilable nitrogen source. Furthermore, mot1.3‐1 plants transformed with a functional copy of MtMOT1.3 showed a wild‐type‐like phenotype.

These data are consistent with a model in which MtMOT1.3 is responsible for introducing molybdate into nodule cells, which is later used to synthesize functional nitrogenase.
Hypopigmented Mycosis Fungoides with Large Cell Transformation in a Child
Authors: Pradhan Dinesh , Jedrych Jaroslaw J. , Ho Jonhan , Akilov Oleg E.
Published: August 2017

Hypopigmented mycosis fungoides (HMF) is the most common variant of mycosis fungoides (MF) in children. Large‐cell transformation in HMF has never been reported. Herein we report a case of HMF in an 8‐year‐old boy who presented with a 6‐year history of hypopigmented patches on the bilateral arms, lower back, buttocks, posterior thighs, and lower legs. Biopsy revealed an abnormal CD8+ epidermotropic T‐cell infiltrate consistent with the diagnosis of MF. The T‐cell clonality study was positive. The patient was started on narrowband ultraviolet B (NBUVB) phototherapy and topical steroids. He had a 50% reduction in his patches after 10 months of treatment, after which he developed a single annular plaque on his left thigh. The biopsy specimen demonstrated large cells that were diffusely CD8+ and CD30−. Clobetasol propionate ointment was prescribed, which led to complete resolution of the plaque within 2 weeks. NBUVB phototherapy was continued and the patient had a complete response within the following 5 months. The case is an example of exceptionally rare large‐cell transformation in pediatric MF and stresses the importance of regular follow‐up of these patients.
CENTRAL PLACE THEORY: AN EVALUATION
Authors: Parr John B.
Published: August 2017

By way of a background to this commentary, the recent history of central place theory is briefly reviewed. Drawing on the work of Christaller and Lösch, attention is initially focused on the particular characteristics of central place goods and on the spatial distribution of their supply. With the aid of export‐base analysis, a distinction is made between central places and specialized function centers, leading to the contention that in contemporary urban systems the central place structure represents one component of a more extensive urban system. Further perspectives on central place theory are revealed by examining some of its deficiencies. In this connection, a distinction is made between limitations inherent to the theory and areas where the theory is deemed to be incomplete or otherwise inadequate. While central place theory is in need of elaboration and extension, it continues to represent a valuable framework within location theory and urban and regional analysis.
Bending Fatigue of Thermal Barrier Coatings
Authors: Eriksson Robert , Chen Zhe , Jonnalagadda Krishna Praveen
Published: August 2017

Thermal barrier coatings (TBCs) are ceramic coatings used in gas turbines to lower the base metal temperature. During operation, the TBC may fail through, for example, fatigue. In this study, a TBC system deposited on a Ni-base alloy was tested in tensile bending fatigue. The TBC system was tested as-sprayed and oxidized, and two load levels were used. After interrupting the tests, at 10,000–50,000 cycles, the TBC tested at the lower load had extensive delamination damage, whereas the TBC tested at the higher load was relatively undamaged. At the higher load, the TBC formed vertical cracks which relieved the stresses in the TBC and retarded delamination damage. A finite element (FE) analysis was used to establish a likely vertical crack configuration (spacing and depth), and it could be confirmed that the corresponding stress drop in the TBC should prohibit delamination damage at the higher load.
Using Personality and Team Identity to Predict Sports Media Consumption
Authors: Devlin Michael B. , Brown-Devlin Natalie
Published: August 2017

The purpose of this study was to first examine the effects of individual personality on the average time spent consuming sport media each week, and then to examine the extent that team identification mediated the effects of personality on sport media consumption. Personality was assessed using the HEXACO Personality Inventory, which provides a theoretical framework to examine the degree to which six broad personality domains and several underlying personality traits influence behavior. A survey using a national sample of 715 participants indicates that personality traits significantly predict team identity, and directly and indirectly predict sport media consumption. Using this personality framework presents a new area of research for sport communication theories and offers practical application for targeting specific types of individuals when promoting mediated sports events. Future research examining the role of personality in a variety of sport communication areas are offered in conclusion.
Interactions between genetic polymorphisms of glucose metabolizing genes and smoking and alcohol consumption in the risk of type 2 diabetes mellitus
Authors: Gao Kaiping , Ren Yongcheng , Wang Jinjin , Liu Zichen , Li Jianna , Li Linlin , Wang Bingyuan , Li Hong , Wang Yaxi , Cao Yunkai , Ohno Kinji , Zhai Rihong , Liang Zhen
Published: August 2017

The impact of gene-environment interaction on diabetes remains largely unknown. We aimed to investigate if interaction between glucose metabolizing genes and lifestyle factors is associated with type 2 diabetes mellitus (T2DM). Interactions between genotypes of 4 glucose metabolizing genes (MTNR1B, KCNQ1, KLF14, and GCKR) and lifestyle factors were estimated in 722 T2DM patients and 759 controls, using multiple logistic regression. No significant associations with T2DM were detected for the single nucleotide polymorphisms of MTNR1B, KLF14 and GCKR. However, rs151290 (KCNQ1) polymorphisms were found to be associated with risk of T2DM. Compared with AA, the odds ratios (ORs) of AC or CC genotypes for developing T2DM were 1.545 (P = 0.0489) and 1.603 (P = 0.0383), respectively. In stratified analyses, the associations were stronger in smokers with CC than smokers with AA (OR = 3.668, P = 0.013); drinkers with AC (OR = 5.518, P = 0.036), CC (OR = 8.691, P = 0.0095), and AC+CC (OR = 6.764, P = 0.016) than drinkers with AA. Compared with nondrinkers with AA, drinkers who carry AC and CC had 12.072-fold (P = 0.0007) and 8.147-fold (P = 0.0052) higher risk of developing T2DM. In conclusions, rs151290 (KCNQ1) polymorphisms are associated with increased risk of T2DM, alone and especially in interaction with smoking and alcohol.
Knockdown of Snail inhibits epithelial–mesenchymal transition of human laryngeal squamous cell carcinoma Hep-2 cells through the vitamin D receptor signaling pathway
Authors: Zhao Xue , Yu Dan , Yang Jingpu , Xue Kai , Liu Yan , Jin Chunshun
Published: August 2017

It has been well documented that Snail plays a decisive role in various tumors. However, the direct effect of Snail on laryngeal squamous cell carcinoma (LSCC) has not been elaborated. In this study, we firstly detected the expression of Snail in 14 samples of patients with LSCC and found that its content was high in cancer tissues compared with adjacent tissues. Then we established LSCC Hep-2 cells with Snail silencing and validated the knockdown efficiency by Western blotting and real-time PCR. Results showed that silencing of Snail significantly inhibited the ability of adhesion, migration, and invasion of Hep-2 cells. Further study revealed that knockdown of Snail suppressed the epithelial–mesenchymal transition (EMT) process of Hep-2 cells, as evidenced by downregulation of matrix metallopeptidase (MMP)-2, MMP-9, integrin subunit beta 1 (ITGβ1), β-catenin, vimentin, N-cadherin, and fibronectin and upregulation of vitamin D receptor (VDR) and E-cadherin. Additionally, transfection with the small interfering RNA of VDR reversed the effect induced by Snail silencing in Hep-2 cells. Taken together, these results demonstrate that knockdown of Snail can inhibit the EMT process of LSCC cells through the VDR signaling pathway in vitro.
Micromechanics-based assessment of reliability and applicability of boundary measurements in symmetrical direct shear test
Authors: Amirpour Harehdasht Samaneh , Roubtsova Varvara , Chekired Mohamed , Hussien Mahmoud N. , Karray Mourad
Published: August 2017

Development of the discrete element method (DEM) has provided an efficient tool to examine and appraise the performance of a direct shear apparatus (DSA) to overcome ambiguities that arise from the complexity of stress and strain distributions involved. This paper presents DEM analyses of both macro- and micromechanics responses of three-dimensional dense samples of 102 248 glass spheres tested in virtual symmetrical DSA using the computer code SiGran. Particular emphasis is placed on the validation of the DEM model by comparing the results of DEM simulations with their physical counterparts at the macroscale. The performance of the physical direct shear apparatus is optimized by exploring modifications to the symmetrical test configuration. Numerical results provide quantitative data on different forms of energy consumed during shearing, confirming other published physical and numerical results found in the literature. Virtual DSA results are also discussed in terms of the coaxiality between the directions of the principal stresses’ and the principal strains’ increments as well as the deviation of the zero extension direction from the horizontal direction. Microscale results show that peak state parameters obtained from the symmetrical arrangement, adopted in this study, are very close to those of an ideal simple shear test, as this arrangement permits a uniform deformation within the developed shear band, a horizontal orientation of the zero linear extension, and a coaxiality of principal stresses and incremental strains at the peak state. In other words, the microscale results presented in this study provide new evidence that corroborates the further use of the boundary measurements in physical symmetrical direct shear tests.
Quarkonium in a thermal BIon
Authors: Sepehri Alireza , Pincak Richard , Hnatič Michal , Rahaman Farook , Pradhan Anirudh
Published: August 2017

In the present article, the authors intend to propose a new theory that potentially allows the propagation of the formation and the evolution of quarkonium in a thermal BIon. When quarks are close to each other, quarkonium behaves like a scalar and, by their getting away, it transitions to a fermionic system. To analyze this particular behaviour, a new outlook approach needs to be adopted as the concurrent view is found deficient to analyse the aforesaid behaviour. Therefore, the authors, post-deliberation, accept that the fermions and fermionic systems are related. We need to accept a theory in which the origin of fermions and bosons is the same. However, in M-theory, these particles are independent and for this reason, we use a new broader theory based on Lie-N algebra and we call it broad Lie-N algebra (BLNA) theory. Thus, in a way, BLNAis M-theory with 11 dimensions. In this model, two types of energies with opposite signs emerge from nothing such that the sum over them becomes zero. They produce two types of branes with opposite quantum numbers and bosonic fields, which interact with each other and get compact. By compacting branes, the quarks and anti-quarks are produced on branes and exchange the graviton and the gravitino. These particles produce two types of wormholes, which act opposite to each other. They preclude the closing or diverging of the branes and also occurrence of confinement. This confined potential that emerges from these wormholes depends on the separation distance between quarks and anti-quarks and also on the temperature of the system and it is reduced to the predicted potential in experiments and QCD. Also, total entropy of this system grows with increasing temperature and produces a repulsive force, which leads to the separation of quarks and anti-quarks and also to the emergence of deconfinement.
An Effective and Efficient Hybrid Algorithm Based on HS–IWO for Global Optimization
Authors: Ouyang Aijia , Peng Shuo , Peng Xuyu , Wang Qian
Published: August 2017

Considering that the invasive weed optimization (IWO) algorithm and the harmony search (HS) algorithm are inclined to fall into local optima with low convergence precision when they are used to deal with complex function optimization problems, this paper proposes a hybrid algorithm, HS–IWO algorithm, which is combined HS algorithm and IWO algorithm. We introduce strategies such as fixing the number of seeds, reinitializing limit solutions, multi-individual global HS, parameter optimization, etc. In order to make the two algorithms take advantage of their merits, they are mixed organically in this paper. Through tests on some complex functions of benchmark, the experimental results display that the HS–IWO algorithm has the efficiency and robustness of the algorithms. It is an optimization algorithm that is highly effective and stable, especially to be applied to the optimization of complicated functions compared with other intelligent optimization algorithms.
Polynomials inducing the zero function on chain rings
Authors: Rogers Mark W. , Wickham Cameron
Published: August 2017

We provide a minimal set of generators for the ideal of polynomials in [Formula: see text] that map the maximal ideal [Formula: see text] into one of its powers [Formula: see text], where [Formula: see text] is a discrete valuation ring with a finite residue field. We use this to provide a minimal set of generators for the ideal of polynomials in [Formula: see text] that send [Formula: see text] to zero, where [Formula: see text] is a finite commutative local principal ideal ring.
Gradient estimates via rearrangements for solutions of some Schrödinger equations
Authors: Yang Sibei , Chang Der-Chen , Yang Dachun , Fu Zunwei
Published: August 2017

In this paper, by applying the well-known method for dealing with [Formula: see text]-Laplace type elliptic boundary value problems, the authors establish a sharp estimate for the decreasing rearrangement of the gradient of solutions to the Dirichlet and the Neumann boundary value problems of a class of Schrödinger equations, under the weak regularity assumption on the boundary of domains. As applications, the gradient estimates of these solutions in Lebesgue spaces and Lorentz spaces are obtained.
Jacobi stability analysis and chaotic behavior of nonlinear double pendulum
Authors: Oiwa Shunya , Yajima Takahiro
Published: August 2017

In this paper, we study the Jacobi stability on the nonlinear double pendulum by the Kosambi–Cartan–Chern (KCC) theory. We assume that the mass and length of rods of two kinds of pendulums are equal, respectively. Moreover, we consider the case that initial angles of the double pendulum are equal. Under these conditions, we obtain the boundary between Jacobi stable and unstable trajectories for initial angles. It is shown that the condition of Jacobi stable or unstable depends only on deflection angles of the nonlinear double pendulum. Then, we discuss relationships between Jacobi stability, physical parameters and other concepts of stability such as Lyapunov stability and chaos. We suggest that the ratio of length of rods and the mass ratio of pendulums of the double pendulum do not affect the Jacobi stability. It is suggested that the equilibrium points in the Jacobi stable region and in the Jacobi unstable region are Lyapunov stable and Lyapunov unstable, respectively, and that the motions in the Jacobi unstable region are related to the onset of chaotic behavior.
Dedekind sums in the p-adic number field
Authors: Girstmair Kurt
Published: August 2017

In a recent note, Kohnen asks whether the values of Dedekind sums are dense in the field of [Formula: see text]-adic numbers. This paper answers this question. Dedekind sums do not approximate units of [Formula: see text] or [Formula: see text], so they are not dense in [Formula: see text] or [Formula: see text]. But they are dense in [Formula: see text] if [Formula: see text].
Fabrication of Porous MoS2 with Controllable Morphology and Specific Surface Area for Hydrodeoxygenation
Authors: Zhang Zhenwi , Yue Chuanjun , Hu Jianhen
Published: August 2017

SiO2 nanoparticles modified with aminopropyl-triethoxysilane (APTES) were used as hard templates for preparing porous MoS2. The method offers the advantages of simple steps, convenient operation, controllable pore size, and a specific surface area. Two morphologies of MoS2 were obtained by using thiourea and L-cysteine as sulfur sources, respectively. Porous MoS2 prepared by using thiourea had a smooth surface, whereas the surface of porous MoS2 prepared with L-cysteine had many burrs. The MoS2 nanomaterials with the respective morphologies were used to catalyze the hydrodeoxygenation (HDO) reaction. The activity of MoS2 prepared with L-cysteine was lower than that prepared with thiourea. Transmission electron microscopy and X-ray diffraction analyses showed that MoS2 had a large sheet-shaped structure and high crystallinity, leading to high reaction activity and high selectivity for cyclohexane. The reaction temperature also influenced the HDO significantly. The mechanism of hydrogenation of phenol was discussed.
Invariants of Lagrangian cobordisms via spectral numbers
Authors: Bisgaard Mads R.
Published: August 2017

We extend parts of the Lagrangian spectral invariants package recently developed by Leclercq and Zapolsky to the theory of Lagrangian cobordism developed by Biran and Cornea. This yields a nondegenerate Lagrangian “spectral metric” which bounds the Lagrangian “cobordism metric” (recently introduced by Cornea and Shelukhin) from below. It also yields a new numerical Lagrangian cobordism invariant as well as new ways of computing certain asymptotic Lagrangian spectral invariants explicitly.
Mimetic Dark Matter in Pseudo-Complex General Relativity
Authors: Volkmer Guilherme Lorenzatto , Hadjimichef Dimiter
Published: August 2017

We investigate the dark matter problem in the context of Pseudo-complex General Relativity. A form of gravitational dark matter has recently been studied, the mimetic dark matter, which is a scalar tensor extension for gravity where the conformal degree of freedom is isolated in a covariant way. For such, we perform a combination of both approaches to reveal non trivial results even in the absence of matter. Solutions for different scenarios and possible interpretations are presented.
STEP as a Decisive Test of MOND on Earth
Authors: Pereira Jonas P.
Published: August 2017

We review and emphasize the importance of the Satellite Test of the Equivalence Principle (STEP) in probing one of the most successful and popular alternative theories to dark matter known as Modified Newtonian Dynamics (MOND), on Earth. This would be achieved with no modification of STEP’s current design and sensitivity and if MOND exists STEP could in principle easily detect it.
Limitation of Gravitational Wave Detector Niobè Sensitivity by the Frequency Tracking Noise
Authors: Frajuca Carlos , Bortoli Fabio da Silva
Published: August 2017

The gravity wave detector at the University of Western Australia was based on a bending flap of [Formula: see text] tuned near the fundamental resonant frequency of a [Formula: see text] resonant-bar of [Formula: see text] at a temperature of [Formula: see text]. The displacement of the bending flap was monitored with a [Formula: see text] superconducting re-entrant cavity transducer. The performance of the transducer is related to the development of a low noise microwave pump oscillator to drive the transducer. This work studies the influence of the frequency tracking noise of Niobè. It had a burst sensitivity of [Formula: see text] with a long term operation from 1993 to early 1998. It had the lowest observed noise temperature. Using the characteristics of the detector, NIOBÈ should had reached a much better sensitivity that the one measure. It seems that the noise introduced in the system by the frequency tracking device was not taken into account at the time of operation, this noise gives a value of [Formula: see text], what is the value that limited the detector sensitivity to the one measured at the time of operation.
Quadrupole Mass Optimization in Very High Speed Using FEM: First Attempt
Authors: Nogueira Paulo R. M. , Frajuca Carlos , Coppedé Daniel , Bortoli Fabio S. , Santos Givanildo A. , Nakamoto Francisco Y.
Published: August 2017

A experiment to measure the velocity of gravity is been planned. In order to achieve a reasonable signal in the detector, a very massive quadrupole mass is put to rotate at a very high rotation speed. In order to maximize the signal, the mass much be as higher as possible. This work test mass geometries in Finite Element Modeling (FEM) with the goal to maximize the resistance to high rotation speed.
Dormant Black Holes
Authors: de Freitas Pacheco José Antonio
Published: August 2017

The growth of supermassive black holes is intermittent, having periods of low accretion when no nuclear activity is seen in the center of the host galaxy. In such dormant state black holes may tidally disrupt stars scattered from the bulge to inside their influence sphere. The resulting debris are partially captured by the black hole forming a short-lived accretion disk, which produces a variable emission dubbed “tidal flare”. Some galaxies candidate to have hosted these tidal events are here considered.
White Dwarf Stars
Authors: Kepler S. O. , Romero Alejandra Daniela , Pelisoli Ingrid , Ourique Gustavo
Published: August 2017

White dwarf stars are the final stage of most stars, born single or in multiple systems. We discuss the identification, magnetic fields, and mass distribution for white dwarfs detected from spectra obtained by the Sloan Digital Sky Survey up to Data Release 13 in 2016, which lead to the increase in the number of spectroscopically identified white dwarf stars from 5[Formula: see text]000 to 39[Formula: see text]000. This number includes only white dwarf stars with [Formula: see text], i.e., excluding the Extremely Low Mass white dwarfs, which are necessarily the byproduct of stellar interaction.
White Dwarf Pulsars and Very Massive Compact Ultra Magnetized White Dwarfs
Authors: Otoniel Edson , Lobato R. V. , Malheiro M. , Franzon Bruno , Schramm Stefan , Weber Fridolin
Published: August 2017

In this work, we discuss white dwarf pulsars found recently making also reference of the possibility of some SGRs/AXPs being part of this class of pulsars. We also study the properties of very massive compact ultra magnetized white dwarfs that could be the progenitors candidates of super luminous type Ia supernovae, and also a previous stage of these white dwarf pulsars before the magnetic field decay.The structure of this ultra magnetized white dwarfs is obtained by solving the Einstein-Maxwell equations with a poloidal magnetic field in a fully general relativistic approach. The stellar interior is composed of a regular crystal lattice made of carbon ions immersed in a degenerate relativistic electron gas. We find that magnetized white dwarfs violate the standard Chandrasekhar mass limit significantly. We obtain a maximum white dwarf mass of around [Formula: see text] with an equatorial radius [Formula: see text] Km, a central magnetic field of [Formula: see text] G and [Formula: see text] G at the stellar surface.
Hybrid Stars in the Framework of NJL Models
Authors: Contrera Gustavo A. , Orsaria Milva , Ranea-Sandoval I. F. , Weber Fridolin
Published: August 2017

We compute models for the equation of state (EoS) of the matter in the cores of hybrid stars. Hadronic matter is treated in the non-linear relativistic mean-field approximation, and quark matter is modeled by three-flavor local and non-local Nambu−Jona-Lasinio (NJL) models with repulsive vector interactions. The transition from hadronic to quark matter is constructed by considering either a soft phase transition (Gibbs construction) or a sharp phase transition (Maxwell construction). We find that high-mass neutron stars with masses up to [Formula: see text] may contain a mixed phase with hadrons and quarks in their cores, if global charge conservation is imposed via the Gibbs conditions. However, if the Maxwell conditions is considered, the appearance of a pure quark matter core either destabilizes the star immediately (commonly for non-local NJL models) or leads to a very short hybrid star branch in the mass-radius relation (generally for local NJL models).
Bayesian Inference Applied to Pulsar’s Models
Authors: Marinho Rubens M. , de Oliveira Heitor O. , Magalhães Nadja S. , Valentim Rodolfo , Coelho Jaziel G. , Alves Márcio E. S.
Published: August 2017

The goal of this work is to apply Bayesian statistics to the problem of pulsars in order to compute the Bayes factor and investigate which one among different EoS could better fit known pulsar data, regarding the rate of decrease of the angular velocity versus the angular velocity itself. We also find the posterior distribution and the best fit for some relevant parameters of the pulsar like the mass and the magnetic field.
Quark-hadron Phase Transition in Proto-Neutron Stars Cores Based on a Non-local NJL Model
Authors: Malfatti German , Orsaria Milva , Contrera Gustavo A. , Weber Fridolin
Published: August 2017

We study the QCD phase diagram using a non-local SU(3) NJL model with vector interactions among quarks. We analyze several thermodynamic quantities such as entropy and specific heat, and study the influence of vector interactions on the thermodynamic properties of quark matter. Upon imposing electric charge neutrality and baryon number conservation on the field equations, we compute models for the equation of state of the inner cores of proto-neutron stars by providing a non-local treatment of quark matter for astrophysics.
Quantum Faraday Effect in the Universe
Authors: Rodríguez Lídice Cruz , Martínez Aurora Pérez , Piccinelli Gabriella , Querts Elizabeth Rodríguez
Published: August 2017

We study the Quantum Faraday rotation starting from the photon self-energy in the presence of a constant magnetic field. The Faraday angle is calculated in the non-degenerate regime and for weak field limit. Two physical scenarios, possibly characterized by these conditions, are the recombination epoch and the jets originated in pulsars. We discuss the resonant behavior that the Faraday angle exhibits in these scenarios and investigate the possibility of detecting cosmic magnetic fields through this resonant mechanism.
Equatorial Geodesics Around the Magnetars
Authors: Alfradique Viviane A. P. , Troconis Orlenys N. , Negreiros Rodrigo P.
Published: August 2017

Neutron stars manifest themselves as different classes of astrophysical sources that are associated to distinct phenomenology. Here we focus our attention on magnetars (or strongly magnetized neutron stars) that are associated to Soft Gamma Repeaters and Anomalous X-ray Pulsars. The magnetic field on surface of these objects, reaches values greater than [Formula: see text] G. Under intense magnetic fields, relativistic effects begin to be decisive for the definition of the structure and evolution of these objects. We are tempted to question ourselves to how strengths fields affect the structure of neutron star. In this work, our objective is study and compare two solutions of Einstein-Maxwell equations: the Bonnor solution, which is an analytical solution that describe the exterior spacetime for a massive compact object which has a magnetic field that is characterize as a dipole field and a complete solution that describe the interior and exterior spacetime for the same source found by numerical methods). For this, we describe the geodesic equations generated by such solutions. Our results show that the orbits generated by the Bonnor solution are the same as described by numerical solution. Also, show that the inclusion of magnetic fields with values up to [Formula: see text]G in the center of the star does not modify sharply the particle orbits described around this star, so the use of Schwarzschild solution for the description of these orbits is a reasonable approximation.
The Gravitomagnetism in the Solar System
Authors: Rocha Flavia , Malheiro Manuel , Marinho Rubens
Published: August 2017

In 1918, Joseph Lense and Hans Thirring discovered the gravitomagnetic (GM) effect of Einstein field equations in weak field and slow motion approximation. They showed that Einstein equations in this approximation can be written as in the same form as Maxwell’s equation for electromagnetism. In these equations the charge and electric current are replaced by the mass density and the mass current. Thus, the gravitomagnetism formalism in astrophysical system is used with the mass assuming the role of the charge. In this work, we present the deduction of gravitoelectromagnetic equations and the analogue of the Lorentz force in the gravitomagnetism. We also discuss the problem of Mercury’s perihelion advance orbit, we propose solutions using GM formalism using a dipole-dipole potential for the Sun-Planet interaction.
Rotational Energy Transfer Non-Reactive Hydrogen-Hydrogen Collisions at Low Temperatures of Astrophysical Interest
Authors: Sultanov Renat A. , Guster Dennis
Published: August 2017

We perform a pure quantum-mechanical calculation for the non-reactive scattering in atomic and molecular hydrogen-hydrogen collisions, i.e. H2+H2 and H+H2. Different potential energy surfaces (PESs) for the H3 and H4 atomic systems have been used. The rigid rotor model of the diatomic molecules, i.e. when the distance between hydrogen atoms is fixed at some average equilibrium value, has been applied in our calculation. After this preparatory stage the astrophysical H2-cooling function can be estimated at different astrophysical conditions and temperatures.
A Heavy-Light Quark Potential
Authors: Gomes Frederico F. , Folador Bruna C. , Hadjimichef Dimiter , da Silva Daniel T.
Published: August 2017

In many studies of meson-baryon interactions with short one gluon exchange potential (OGEP), usually a full non-relativistic reduction, at the quark level Hamiltonian, is performed. In systems like [Formula: see text], light and heavy quarks are present, which in principle would require only a partial non-relativistic reduction. We shal start from a JKJ relativistic quark Hamiltonian and apply a partial non-relativistic reduction in order to obtain a OGEP between heavy and light quarks (heavy-light quark potential).
QCD Phase Diagram in a Nonlocal SU(3) NJL Model with Lattice-Inspired Form Factors
Authors: Villafañe María Florencia Izzo , Carlomagno Juan Pablo , Dumm Daniel Gómez , Scoccola Norberto N.
Published: August 2017

We study the QCD phase diagram in the framework of a nonlocal three-flavor quark model. We determine the model parameters from vacuum meson phenomenology, considering lattice QCD-inspired nonlocal form factors. Then we analyze the features of the deconfinement and chiral restoration transitions for systems at nonzero temperature and chemical potential.
The Exclusive Photoproduction of Υ(1S,2S,3S) in pp and pA Collisions at LHC Energies
Authors: Gay Ducati Maria Beatriz , Kopp Fabio
Published: August 2017

We presented the exclusive photoproduction of Upsilon(1S,2S,3S) in pp and pA reactions at the LHC energies for Ultra Peripheral Collisions(UPC). It was calculated in the dipole formalism, with the dipoles models: GBW, CGC and b-CGC. The dipole formalism is characterised by a saturation effect, e.g, the mimic gluon distribution becomes saturated at low-x. This approach has shown a good agreement with the experimental data since HERA and with recent data released by LHCb for processes involving [Formula: see text], [Formula: see text], [Formula: see text] for UPC in pp.
Investigating the Prompt Photon Production at the LHC Energies
Authors: dos Santos Glauber S. , Machado Magno V. T.
Published: August 2017

We investigate the rapidity and transverse momentum distributions of the prompt photon production at the LHC energies considering the color dipole approach. We compare the predictions from distinct models for the dipole cross section, where parton saturation models at high energies are expected to be important at the forward rapidities in [Formula: see text] and [Formula: see text] collisions at the LHC.
Photon-Photon Interaction in Glueball Production
Authors: da Silva Daniel T. , da Silva Mario L. L. , Hadjimichef Dimiter
Published: August 2017

In the last years many exotic states have been identified in several colliders around the world. One of the exotic states provided in QCD is the glueball. Using a non-relativistic gluon bound-state model, we compute [Formula: see text], where [Formula: see text] is a pseudoscalar, tensor, or scalar digluon. For the starting from the amplitudes we considers the process [Formula: see text] at threshold, where the amplitudes are obtained in perturbative QCD at lowest order by deriving them from QED calculation and the [Formula: see text]s are massive constituent gluons. In this calculation the unknown parameters of the model, such as the digluon wave function, are obtained using measured values of [Formula: see text]. Our theorical results are compared with the present experimental limits for the various glueballs candidates.
Bound State Correction in CP Violation
Authors: Rodrigues Hercules B. , da Silva Daniel T. , Hadjimichef Dimiter
Published: August 2017

We study hadronic weak decays using an approach which consists in a mapping technique, the Fock-Tani formalism, in order to obtain an effective weak Hamiltonian starting from a contact microscopic interaction. An additional effect is manifest in this formalism associated to the extended nature of mesons: bound-state corrections which can be related to CP violation parameters.
RCMC
Authors: Assem Haytham , Buda Teodora Sandra , O’sullivan Declan
Published: August 2017

During the past few years, the analysis of data generated from Location-Based Social Networks (LBSNs) have aided in the identification of urban patterns, understanding activity behaviours in urban areas, as well as producing novel recommender systems that facilitate users’ choices. Recognizing crowd-mobility patterns in cities is very important for public safety, traffic managment, disaster management, and urban planning. In this article, we propose a framework for Recognizing the Crowd Mobility Patterns in Cities using LBSN data. Our proposed framework comprises four main components: data gathering, recurrent crowd-mobility patterns extraction, temporal functional regions detection, and visualization component. More specifically, we employ a novel approach based on Non-negative Matrix Factorization and Gaussian Kernel Density Estimation for extracting the
recurrent crowd-mobility patterns
in cities illustrating how crowd shifts from one area to another during each day across various time slots. Moreover, the framework employs a hierarchical clustering-based algorithm for identifying what we refer to as
temporal functional regions
by modeling functional areas taking into account temporal variation by means of check-ins’ categories. We build the framework using a spatial-temporal dataset crawled from Twitter for two entire years (2013 and 2014) for the area of Manhattan in New York City. We perform a detailed analysis of the extracted crowd patterns with an exploratory visualization showing that our proposed approach can identify clearly obvious mobility patterns that recur over time and location in the urban scenario. Using same time interval, we show that correlating the temporal functional regions with the recognized recurrent crowd-mobility patterns can yield to a deeper understanding of city dynamics and the motivation behind the crowd mobility. We are confident that our proposed framework not only can help in managing complex city environments and better allocation of resources based on the expected crowd mobility and temporal functional regions but also can have a direct implication on a variety of applications such as personalized recommender systems, anomalous event detection, disaster resilience management systems, and others.
Collapsible Pushdown Automata and Recursion Schemes
Authors: Hague Matthew , Murawski Andrzej S. , Ong C.-H. Luke , Serre Olivier
Published: August 2017

We consider recursion schemes (not assumed to be
homogeneously typed
, and hence not necessarily
safe
) and use them as generators of (possibly infinite) ranked trees. A recursion scheme is essentially a finite typed deterministic term rewriting system that generates, when one applies the rewriting rules
ad infinitum
, an infinite tree, called its
value tree
. A fundamental question is to provide an equivalent description of the trees generated by recursion schemes by a class of machines.

In this article, we answer this open question by introducing
collapsible pushdown automata
(CPDA), which are an extension of deterministic (higher-order) pushdown automata. A CPDA generates a tree as follows. One considers its transition graph, unfolds it, and contracts its silent transitions, which leads to an infinite tree, which is finally node labelled thanks to a map from the set of control states of the CPDA to a ranked alphabet.

Our contribution is to prove that these two models, higher-order recursion schemes and collapsible pushdown automata, are equi-expressive for generating infinite ranked trees. This is achieved by giving effective transformations in both directions.