bluuebunny/crossref_metadata_2025 huggingface dataset:
Multilayer Nickel–Copper Anode for Direct Glucose Fuel Cell
Authors: Maizelis Antonina
Published: March 2019

Multilayer nickel–copper coatings consisting of layers of nickel–copper alloy and a mixture of metals with hydroxides were obtained by electrodeposition from polyligand pyrophosphate–ammonia electrolyte by the two-pulse potentiostatic method. A comparison between two different electrodes with the same real surface area is presented. The equality of the surface area of electrodes deposited from the electrolyte containing different copper and nickel ions’ concentration ratio was achieved by deposition of different numbers of layers. It is shown that the increase in the copper content in electrolyte leads to an increase in the copper ions’ content in the coating and the electrode surface develops more intensively. Freshly deposited coatings have approximately the same catalytic activity in the glucose oxidation reaction in the alkaline solution. But a multilayer coating with a higher copper content is more corrosion resistant and more stable in long-term electrolysis.
Comparative Analysis Between Water-Cooled and Air-Cooled Heat Dissipation in a High-Power Light-Emitting Diode Chipset
Authors: Chen Yuanlong , Hou Tingbo , Pan Minqiang
Published: March 2019

With a substantial increase in thermal power density, the operating temperature of high-power light-emitting diodes (LEDs) rises rapidly, exerting a notable effect on chipsets’ performance. A water-cooled microchannel radiator and an air-cooled radiator are proposed to solve this problem. The effects of key factors of both radiators on heat dissipation in a high-power LED chipsets, and general comparisons between each method, are analyzed via Fluent. The simulation results indicate that heat dissipation from the water-cooled microchannel radiator is readily affected by the microchannel’s flow rate and aspect ratio. A larger flow rate and larger aspect ratio favor improved heat dissipation in the water-cooled microchannel radiator. Heat dissipation in the air-cooled radiator is related to volumetric flow rate, rib number, rib height, rib thickness, and substrate thickness. A larger volumetric flow rate, rib number, and rib height favor heat dissipation in the air-cooled radiator. However, there is a critical thickness value: if the thickness is less than the critical value, heat dissipation is greatly affected by rib thickness and substrate thickness, if the thickness is larger than the critical value, the influence is insignificant. The high-power LED chipsets’ temperature is also related to the insulating substrate’ input power and thermal conductivity. A large input power leads to a substantial increase in temperature, and larger thermal conductivity of the insulating substrate minimizes temperature increase in the high-power LED chipsets. When comparing the two radiators, results show an air-cooled radiator should be used in low-power LED chipsets. When an air-cooled radiator cannot satisfy the chipset’s needs, a water-cooled microchannel radiator should be utilized.
Novel Gear Transmission Mechanism With Twice Unequal Amplitude Transmission Ratio
Authors: Yu Gaohong , Tong Zhipeng , Sun Liang , Tong Junhua , Zhao Xiong
Published: March 2019

The operation effectiveness of multi-bar transplanting mechanisms is low, and the specific changing law of the transmission ratio (the curve of the transmission ratio has twice unequal amplitude [TUA] fluctuation.), which is needed in vegetable pot seedling transplanting, is difficult to fulfill using a planetary gear train with noncircular gears and a single-planet carrier. To address this problem, we propose a noncircular gear pair that comprises an incomplete noncircular gear, rack, partial noncircular gear, and elliptical gear. The structural characteristics and the working principle of the TUA gear pair were analyzed. The pitch curve equation of the noncircular TUA gears was derived from the relationship of the angular displacement of the corresponding pitch curves. The influence of central angle α and eccentricity k on the shape of the pitch curve, angular displacement, and transmission ratio of the TUA gear pair was analyzed. The TUA gear pair was applied to a proposed vegetable seedling pickup mechanism (SPM) considering the design requirements. Finally, the feasibility of the new noncircular TUA gear transmission mechanism was verified by an SPM test.
Age effects on the contributions of envelope and periodicity cues to recognition of interrupted speech in quiet and with a competing talker
Authors: Bologna William J. , Vaden Kenneth I. , Ahlstrom Jayne B. , Dubno Judy R.
Published: March 2019

Envelope and periodicity cues may provide redundant, additive, or synergistic benefits to speech recognition. The contributions of these cues may change under different listening conditions and may differ for younger and older adults. To address these questions, younger and older adults with normal hearing listened to interrupted sentences containing different combinations of envelope and periodicity cues in quiet and with a competing talker. Envelope and periodicity cues improved speech recognition for both groups, and their benefits were additive when both cues were available. Envelope cues were particularly important for older adults and for sentences with a competing talker.
Reaction of a Tantalum Alkylidene Complex with Dinuclear Metal Carbonyls: Formation of C
3
ligands
Authors: Proulx Grant , Bergman Robert G.
Published: March 2019

The mechanisms of reactions that deoxygenate carbon monoxide (CO) and convert it into longer chain hydrocarbons are not well understood. A series of reactions between "early" and "late" transition metal complexes that result in CO coupling reactions in a homogeneous solution are reported. In one example, the Schrock tantalum-methylene complex (η
5
-C
5
H
2
)
2
Ta(CH
2
)(CH
3
) reacts with the dinuclear metal carbonyls CO
2
(CO)
8
and Fe
2
(CO)
9
in a novel fashion to yield a C
3
H
2
O
2
ligand bridging three metal centers. Reaction of the tantalum-methylene complex with Re
2
(CO)
10
leads to an even more substantial change in which extensive rearrangement along with three-carbon coupling occurs. An oxygen atom is removed from one CO group, leading to the novel oxotantalum compound (η
5
-C
5
H
5
)
2
(CH
3
)Ta=O. Simultaneously, the carbon atom from the transformed CO couples with two CH
2
groups initially bound to tantalum and the CH
2
hydrogens are rearranged to produce a CH
3
-CC ligand. Low-temperature nuclear magnetic resonance and isotope tracer experiments have provided preliminary information about the mechanisms of these unusual carbon-carbon bond-forming reactions.
Microstructural Observations of α-Quartz Amorphization
Authors: Kingma Kathleen J. , Meade Charles , Hemley Russell J. , Mao Ho-kwang , Veblen David R.
Published: March 2019

Solid-state amorphization is a transformation that has been observed in a growing number of materials. Microscopic observations indicate that amorphization of a-quartz begins with formation of crystallographically controlled planar defects and is followed by growth of amorphous silicon dioxide at these defect sites. Similar transformation microstructures are found in quartz upon quasihydrostatic and nonhydrostatic compression in a diamond-anvil cell to 40 gigapascals and from simple comminution. The results suggest that there is a common mechanism for solid-state amorphization of silicates in static and shock high-pressure experiments, meteorite impact, and deformation by tectonic processes. In general, these results are consistent with recently proposed shear instability models of amorphization.
Brexit's looming effects vex U.K. researchers
Authors: Stokstad Erik
Published: March 2019

U.K. scientists prepare for possible crash out of Europe by stockpiling supplies.
Impact craters on Pluto and Charon indicate a deficit of small Kuiper belt objects
Authors: Singer K. N. , McKinnon W. B. , Gladman B. , Greenstreet S. , Bierhaus E. B. , Stern S. A. , Parker A. H. , Robbins S. J. , Schenk P. M. , Grundy W. M. , Bray V. J. , Beyer R. A. , Binzel R. P. , Weaver H. A. , Young L. A. , Spencer J. R. , Kavelaars J. J. , Moore J. M. , Zangari A. M. , Olkin C. B. , Lauer T. R. , Lisse C. M. , Ennico K. ,   New Horizons Geology, Geophysics and Imaging Science Theme Team,   New Horizons Surface Composition Science Theme Team,   New Horizons Ralph and LORRI Teams, Buie Marc W. , Buratti Bonnie J. , Cheng Andrew F. , Cook Jason C. , Cruikshank Dale P. , Dalle Cristina M. , Earle Alissa M. , Horanyi Mihaly , Howett Carly J. A. , Jennings Don E. , Linscott Ivan R. , Lunsford Allen W. , Protopapa Silvia , Reitsema Harold J. , Reuter Dennis C. , Showalter Mark R. , Tyler G. Leonard , Weigle G. E.
Published: March 2019

Impact craters on Pluto and Charon

Collisions between Solar System bodies produce impact craters on large objects at a rate that depends on the population of impacting small bodies. Singer
et al.
examined impact craters on Pluto and its moon Charon. Some regions have had their impact craters erased by recent geological processes, but others appear to record 4 billion years of impacts. Because Pluto and Charon are located in the Kuiper belt, the distribution of crater sizes reflects the size distribution of impacting Kuiper belt objects (KBOs). The authors found fewer small KBOs than predicted by models of collision equilibrium, implying that some of the KBO population has been preserved since the formation of the Solar System.

Science
, this issue p.
955
Quantum-critical conductivity of the Dirac fluid in graphene
Authors: Gallagher Patrick , Yang Chan-Shan , Lyu Tairu , Tian Fanglin , Kou Rai , Zhang Hai , Watanabe Kenji , Taniguchi Takashi , Wang Feng
Published: March 2019

Electron hydrodynamics in graphene

Electrons can move through graphene in a manner reminiscent of fluids, if the conditions are right. Two groups studied the nature of this hydrodynamic flow in different regimes (see the Perspective by Lucas). Gallagher
et al.
measured optical conductivity using a waveguide-based setup, revealing signatures of quantum criticality near the charge neutrality point. Berdyugin
et al.
focused on electron transport in the presence of a magnetic field and measured a counterintuitive contribution to the Hall response that stems from hydrodynamic flow.

Science
, this issue p.
158
, p.
162
; see also p.
125
Binodal, wireless epidermal electronic systems with in-sensor analytics for neonatal intensive care
Authors: Chung Ha Uk , Kim Bong Hoon , Lee Jong Yoon , Lee Jungyup , Xie Zhaoqian , Ibler Erin M. , Lee KunHyuck , Banks Anthony , Jeong Ji Yoon , Kim Jongwon , Ogle Christopher , Grande Dominic , Yu Yongjoon , Jang Hokyung , Assem Pourya , Ryu Dennis , Kwak Jean Won , Namkoong Myeong , Park Jun Bin , Lee Yechan , Kim Do Hoon , Ryu Arin , Jeong Jaeseok , You Kevin , Ji Bowen , Liu Zhuangjian , Huo Qingze , Feng Xue , Deng Yujun , Xu Yeshou , Jang Kyung-In , Kim Jeonghyun , Zhang Yihui , Ghaffari Roozbeh , Rand Casey M. , Schau Molly , Hamvas Aaron , Weese-Mayer Debra E. , Huang Yonggang , Lee Seung Min , Lee Chi Hwan , Shanbhag Naresh R. , Paller Amy S. , Xu Shuai , Rogers John A.
Published: March 2019

Sensitive sensing

Neonatal care, particularly for premature babies, is complicated by the infants' fragility and by the need for a large number of tethered sensors to be attached to their tiny bodies. Chung
et al.
developed a pair of sensors that only require water to adhere to the skin and allow for untethered monitoring of key vital signs (see the Perspective by Guinsburg). On-board data processing allowed for efficient wireless near-field communication using standard protocols. The absence of cables makes it easier to handle the infants and allows for skin-to-skin contact between the babies and their parents or caregivers.

Science
, this issue p.
eaau0780
; see also p.
924
Improving care of critically ill newborns
Authors: Guinsburg Ruth
Published: March 2019

Wireless monitoring of neonates can decrease skin injuries and allow natural mobility
Natural climate solutions are not enough
Authors: Anderson Christa M. , DeFries Ruth S. , Litterman Robert , Matson Pamela A. , Nepstad Daniel C. , Pacala Stephen , Schlesinger William H. , Shaw M. Rebecca , Smith Pete , Weber Christopher , Field Christopher B.
Published: March 2019

Decarbonizing the economy must remain a critical priority
Precise vocal timing needs cortical control
Authors: Hage Steffen R.
Published: March 2019

The evolution of vocal communication systems is investigated in a rodent model
Lipid-filled vesicles modulate macrophages
Authors: Antonyak Marc A. , Lukey Michael J. , Cerione Richard A.
Published: March 2019

Fat cells use a special form of intercellular communication to shape their environment
Speaking truth to power
March 4: Scientists, Students, and Society
Jonathan Allen, Ed.
MIT Press, 2019. 200 pp.
Authors: Wolfe Audra J.
Published: March 2019

Fifty years after MIT's memorable protest, a key question remains: Should scientists ask for change or should they demand it?
Targeted and Repetitive Chromosomal Integration Enables High-Level Heterologous Gene Expression in
Lactobacillus casei
Authors: Xin Yongping , Mu Yingli , Kong Jian , Guo Tingting
Published: March 2019

Lactic acid bacteria (LAB), including
Lactobacillus casei
, have the potential for overexpression of heterologous proteins, such as bioactive molecules and enzymes. However, traditional genetic tools for expression of these proteins show genetic instability or low yields of the desired product. In this study, we provide a procedure for repetitive integration of genes at various chromosomal locations, achieving high-level and stable expression of proteins in
Lb. casei
without selective pressure. The protocol developed in this study provides an essential reference for chromosomal overexpression of proteins or bioactive molecules in LAB.
Stress-Responsive Alternative Sigma Factor SigB Plays a Positive Role in the Antifungal Proficiency of
Bacillus subtilis
Authors: Bartolini M. , Cogliati S. , Vileta D. , Bauman C. , Ramirez W. , Grau R.
Published: March 2019

Biological control using beneficial bacteria (PGPRs) represents an attractive and environment-friendly alternative to pesticides for controlling plant diseases. Different PGPR
Bacillus
species produce potent biofungicides and stimulate plant defense responses against phytopathogenic fungi. However, very little is known about how PGPRs recognize phytopathogens and process the antifungal response. Here, we report how
B. subtilis
triggers the induction of the stress-responsive sigma B transcription factor and the synthesis of the lipopeptide surfactin to fight the phytopathogen. Our findings show the participation of the stress-responsive regulon of PGPR
Bacillus
in the detection and biocontrol of a phytopathogenic fungus of agronomic impact.
Congenital left heart obstruction: ethnic variation in incidence and infant survival
Authors: Cloete Elza , Sadler Lynn , Bloomfield Frank H , Crengle Sue , Percival Teuila , Gentles Thomas L
Published: March 2019

Objective

To investigate the relationship between ethnicity and health outcomes among fetuses and infants with congenital left heart obstruction (LHO).

Design

A retrospective population-based review was conducted of fetuses and infants with LHO including all terminations, stillbirths and live births from 20 weeks’ gestation in New Zealand over a 9-year period. Disease incidence and mortality were analysed by ethnicity and by disease type: hypoplastic left heart syndrome (HLHS), aortic arch obstruction (AAO), and aortic valve and supravalvular anomalies (AVSA).

Results

Critical LHO was diagnosed in 243 fetuses and newborns. There were 125 with HLHS, 112 with AAO and 6 with isolated AVSA. The incidence of LHO was significantly higher among Europeans (0.59 per 1000) compared with Māori (0.31 per 1000; p<0.001) and Pacific peoples (0.27 per 1000; p=0.002). Terminations were uncommon among Māori and Pacific peoples. Total case fatality was, however, lower in Europeans compared with other ethnicities (42% vs 63%; p=0.002) due to a higher surgical intervention rate and better infant survival. The perinatal and infant mortality rate was 82% for HLHS, 15% for AAO and 2% for AVSA.

Conclusion

HLHS carries a high perinatal and infant mortality risk. There are ethnic differences in the incidence of and mortality from congenital LHO with differences in mortality rate suggesting inequities may exist in the perinatal management pathway.
Hydroxychloroquine-induced inverse psoriasis
Authors: Ullah Asad , Zeb Hassan , Khakwani Zeeshan , Murphy Frederick T
Published: March 2019

A 65-year-old woman presented to our rheumatology clinic with pain and swelling of multiple joints of her hands. After a thorough evaluation, she was diagnosed with rheumatoid arthritis and was started on hydroxychloroquine therapy. A week later, she presented to our clinic with an acute condition and reported that after taking hydroxychloroquine for a few days she developed multiple rashes, most prominent at skin folds around her breasts, neck, axillae and buttocks. The rashes were characteristic of inverse psoriasis. Hydroxychloroquine was discontinued and the patient was started on methotrexate therapy that resulted in resolution of her rashes in a week.
Uncontrolled diabetes as a rare presenting cause of pituitary apoplexy
Authors: Mittal Ashima , Mishra Sanat , Yadav Karamvir , Rajput Rajesh
Published: March 2019

Pituitary apoplexy is a rare endocrine emergency. The extent to which hyperglycaemia is a contributory risk factor in the precipitation of pituitary apoplexy is not known. A 38-year-old man with poorly controlled diabetes presented to the emergency department with sudden onset of nausea and headache with drooping of his right eyelid for about 4 days. On physical examination, he had orthostatic hypotension, ptosis of the right eye, lateral and downward positioning of the eye and absent pupillary reflex. Visual field testing of the left eye revealed superolateral quadrantanopia. MRI of the brain showed pituitary macroadenoma with necrosis. Investigations showed hyperglycaemia, decreased T3, T4 with normal Thyroid stimulating hormone (TSH), low serum Leutinizing hormone (LH), Follicle stimulating hormone (FSH), testosterone and low normal serum prolactin levels. About 21% of non-functioning pituitary adenomas present with apoplexy as was seen in our patient. It is likely that his uncontrolled diabetes precipitated this episode of apoplexy as hyperosmolarity and dehydration, caused by hyperglycaemia can lead to changed pituitary microvascular environment increasing the risk of pituitary infarction.
Inverted papilloma of the conjunctiva
Authors: Ramberg Ingvild , Sjö Nicolai Christian , Bonde Jesper Hansen , Heegaard Steffen
Published: March 2019

Objective

The purpose of the present study is to describe the clinical and histopathological features of conjunctival inverted papilloma, to analyse for the presence of human papillomavirus (HPV), and to determine if HPV infection is associated with this type of tumour and its inverted growth pattern.

Methods and Analysis

Cases of conjunctival inverted papillomas were retrieved from the archives of the Department of Pathology, Rigshospitalet, Denmark. Patient records and pathology reports were reviewed. Formalin-fixed and paraffin-embedded tissue was analysed for the presence of HPV by immunohistochemistry, in situ hybridisation (ISH), PCR and HPV typed by sequencing.

Results

A total of four cases were retrieved. The age at diagnosis ranged from 41 to 77 years, with an equal sex distribution. All lesions were localised to the bulbar conjunctiva and two of the cases were pigmented. Histopathological examination did not reveal areas of dysplasia. All lesions were p16-positive and p53-positive by immunohistochemistry. High-risk HPV 58 was demonstrated in one lesion by ISH and PCR.

Conclusion

Here we present four cases of conjunctival inverted papilloma, which is an exceedingly rare tumour with only 11 previously reported cases in the literature. Both clinically and histopathologically, the tumours show distinct features compared with exophytic conjunctival papillomas. Furthermore, this is the first description of high-risk HPV 58 in a conjunctival tumour. The biological behaviour of the tumour is uncertain due to its rareness. However, a complete removal of the lesion and a careful observation are recommended. The finding of HPV 58 underlines the necessity of this precaution.
3D-printed compact XRF spectrometer
Authors: Sugino Tomohiro , Tanaka Ryohei , Kawai Jun , Takenami Yusuke , Kadono Jun-ichiro
Published: March 2019

In order to address the applicability of 3D printers to assembling a spectrometer, we made a compact energy dispersive X-ray fluorescence (XRF) spectrometer with the use of a 3D printer and applied it to the measurements of trace elements in multicomponent alloys. The spectrometer was made of polycarbonate. The X-ray path was in the air, and the distance between equipment was designed so as to obtain enough input count rate even though a low-power X-ray source was employed. As an X-ray source and a detector, we used a low-power X-ray tube (4 watts) and a silicon drift detector. Although the effect of scattered X-rays from resin materials on measured spectra should be taken into account, the 3D-printed spectrometer was comparable with the conventional spectrometer in terms of the qualitative analysis. By using the simple 3D-printed spectrometer, trace elements included in stainless steels and an Ni-based alloy could be detected. 3D printers should therefore provide a simple and quick way of making an improvement on analytical instruments combined with the conventional way.
Use of a slit feedback system based on a proportional-integral controller to improve long- and short-term voltage stability during microbeam experiments
Authors: Matsuyama S. , Miwa M. , Toyama S. , Fujisawa M. , Sato Y. , Kikuchi Y. , Fujiwara M. , Suzuki S. , Nagaya T.
Published: March 2019

We developed a terminal voltage stabilization system (TVSS) to improve the high-voltage properties of the Dynamitron accelerator in microbeam experiments. However, a voltage deviation of ca. 1 Hz increased gradually over time because of power variation in the oscillation tube. The deviation was caused by feedback phase delay and the low sensitivity of the generating voltage meter (GVM). By optimizing the feedback parameters, the voltage deviation was greatly reduced, even when old oscillation tubes were used. The optimum parameters were strongly dependent on tube conditions. By combining gain-adjustable proportional-integral (PI) and proportional (P) circuits in the feedback system, the parameters can be changed, even during accelerator operation, and remain adjustable over a long period. The low sensitivity of the GVM prohibits voltage regulation at [Formula: see text][Formula: see text]100 V. We developed a slit feedback system to compensate for this weakness. The voltage ripple became ca. [Formula: see text] at [Formula: see text][Formula: see text]1 Hz even using old oscillation tubes. Although the ripple [Formula: see text][Formula: see text]1 Hz was difficult to validate because of vibration of the high-voltage terminal, the ripple at [Formula: see text][Formula: see text]10 Hz was greatly reduced with use of this mode. The modified TVSS is now used routinely during microbeam experiments.
Parallel Simultaneous Perturbation Optimization
Authors: Alaeddini Atiye , Klein Daniel J.
Published: March 2019

Stochastic computer simulations enable users to gain new insights into complex physical systems. Optimization is a common problem in this context: users seek to find model inputs that maximize the expected value of an objective function. The objective function, however, is time-intensive to evaluate, and cannot be directly measured. Instead, the stochastic nature of the model means that individual realizations are corrupted by noise. More formally, we consider the problem of optimizing the expected value of an expensive black-box function with continuously-differentiable mean, from which observations are corrupted by Gaussian noise. We present parallel simultaneous perturbation optimization (PSPO), which extends a well-known stochastic optimization algorithm, simultaneous perturbation stochastic approximation, in several important ways. Our modifications allow the algorithm to fully take advantage of parallel computing resources, like high-performance cloud computing. The resulting PSPO algorithm takes fewer time-consuming iterations to converge, automatically chooses the step size, and can vary the error tolerance by step. Theoretical results are supported by a numerical example.
A systematic expansion of running couplings and masses
Authors: Chishtie F. A. , McKeon D. G. C. , Sherry T. N.
Published: March 2019

As an alternative to directly integrating their defining equations to find the running coupling [Formula: see text] and the running mass [Formula: see text], we expand these quantities in powers of [Formula: see text] and their boundary values [Formula: see text] and [Formula: see text]. Renormalization group summation is used to partially sum these logarithms. We consider this approach using both the [Formula: see text] and ’t Hooft renormalization schemes. We also show how the couplings and masses in any two mass independent renormalization schemes are related.
Vacuum polarization of weak interaction theory in Krein space quantization
Authors: Forghan B.
Published: March 2019

In this paper, one of the most important diagrams of weak interaction (vacuum polarization) is studied in Krein space quantization (KSQ). This diagram has divergent terms in Hilbert space which must be eliminated using a traditional regularization method like dimensional regularization whereas in KSQ the result is automatically finite and does not need renormalization.
Gauss–Bonnet gravity in D = 4 without Gauss–Bonnet coupling to matter: Cosmological implications
Authors: Guendelman Eduardo , Nissimov Emil , Pacheva Svetlana
Published: March 2019

We propose a new model of D = 4 Gauss–Bonnet gravity. To avoid the usual property of the integral over the standard D = 4 Gauss–Bonnet scalar becoming a total derivative term, we employ the formalism of metric-independent non-Riemannian spacetime volume elements which makes the D = 4 Gauss–Bonnet action term nontrivial without the need to couple it to matter fields unlike the case of ordinary D = 4 Gauss–Bonnet gravity models. The non-Riemannian volume element dynamically triggers the Gauss–Bonnet scalar to be an arbitrary integration constant M on-shell, which in turn has several interesting cosmological implications. (i) It yields specific solutions for the Hubble parameter and the Friedmann scale factor as functions of time, which are completely independent of the matter dynamics, i.e. there is no back reaction by matter on the cosmological metric. (ii) For M[Formula: see text]0, it predicts a “coasting”-like evolution immediately after the Big Bang, and it yields a late universe with dynamically produced dark energy density given through M. (iii) For the special value M = 0, we obtain exactly a linear “coasting” cosmology. (iv) For M[Formula: see text]0, we have in addition to the Big Bang also a Big Crunch with “coasting”-like evolution around both. (v) It allows for an explicit analytic solution of the pertinent Friedmann and [Formula: see text] scalar field equations of motion, while dynamically fixing uniquely the functional dependence on [Formula: see text] of the scalar potential.
Hawking radiation from cubic and quartic black holes via tunneling of GUP corrected scalar and fermion particles
Authors: Javed Wajiha , Babar Rimsha , Övgün Ali
Published: March 2019

We analyze the effect of the generalized uncertainty principle (GUP) on the Hawking radiation from the hairy black hole in U(1) gauge-invariant scalar–vector–tensor theory by utilizing the semiclassical Hamilton–Jacobi method. To do so, we evaluate the tunneling probabilities and Hawking temperature for scalar and fermion particles for the given spacetime of the black holes with cubic and quartic interactions. For this purpose, we utilize the modified Klein–Gordon equation for the Boson particles and then Dirac equations for the fermion particles, respectively. Next, we examine that the Hawking temperature of the black holes do not depend on the properties of tunneling particles. Moreover, we present the corrected Hawking temperature of scalar and fermion particles which look similar in both interactions, but there are different mass and momentum relationships for scalar and fermion particles in cubic and quartic interactions.
Distorted vacuum black holes in the canonical ensemble
Authors: Zaslavskii O. B.
Published: March 2019

We consider a vacuum static spacetime in a finite size cavity. On the boundary, we specify a metric and a finite constant local temperature [Formula: see text]. No spherical or any other spatial symmetry is assumed. We show that (i) inside a cavity, only a black hole or flat spacetime are possible, whereas a curved horizonless regular spacetime is excluded, (ii) in the limit when the horizon area shrinks, the Hawking temperature diverges, (iii) for the existence of a black hole, [Formula: see text] should be high enough. When [Formula: see text], a black hole phase is favorable thermodynamically. Our consideration essentially uses the coordinate system introduced by Israel in his famous proof of the uniqueness theorem.
On the Higgs mass fine-tuning problem with multi-Higgs doublet models
Authors: Chakrabarty Nabarun , Chakraborty Indrani
Published: March 2019

With no conclusive signal till date of the minimal supersymmetric and extra-dimensional models at the Large Hadron Collider (LHC), the issue of naturalness of the Higgs mass still calls for attention. One way to achieve that is to introduce additional bosonic degrees of freedom and rely on fine-tuning thereafter. That is, to arrange for a cancellation between various parameters so that the coefficient of the quadratically divergent term in the Higgs mass is vanishing or small to a manageable level. In this work, we explore the possibility of doing so using two- and three-Higgs doublet models. We consider different versions of the same and fold in various relevant constraints accordingly. The study reveals that the quadratically divergent mass term of the 125 GeV Higgs can be exactly canceled in most of the models considered here. However, the same does not hold for the nonstandard scalars owing to the applied constraints.
The hardest TC self-energy behavior and radiative corrections in a 331-TC model
Authors: Doff A.
Published: March 2019

The solution of the phenomenological problems of technicolor (TC) models may reside in the different dynamical behaviors of the technifermions self-energy appearing in walking (or quasi-conformal) theories. Motivated by recent results, where it is shown how the boundary conditions (BC) of the anharmonic oscillator representation of the Schwinger–Dyson gap equation (SDE) to [Formula: see text] are directly related with the mass anomalous dimensions, and different BC cause a change in the ultraviolet asymptotic behavior of the self-energies, in this paper, we verify that it is possible to have a hard technifermion self-energy in TC models originated through radiative corrections coming from the interactions mediated by the new massive neutral and charged gauge bosons, [Formula: see text] and [Formula: see text] in the context of a 331-TC model.
Effects of ternary mixed crystals on interface/surface optical phonon in spherical core-shell quantum dots
Authors: Liu Y. , Liu L. P. , Xing Y. , Liang X. X.
Published: March 2019

Within the framework of the dielectric continuum approach and modified random-element-isodisplacement model, the optical vibration mode in a spherical core-shell quantum dot (CSQD) consisting of ternary mixed crystals (TMCs) are investigated. The dispersion relation and electron–phonon interaction Hamiltonian are derived. As a typical case, the numerical results for [Formula: see text] and [Formula: see text] CSQDs are obtained and discussed. Taking the one- and two-mode behaviors of TMCs into account, the effects of TMCs on interface/surface optical (IO/SO) phonon show that there are 3 and 5 branches of IO/SO phonon modes in [Formula: see text] and [Formula: see text] CSQDs for a given component of TMC, respectively. It is also found that the IO/SO phonon frequencies and electron–phonon interactions are strongly dependent on the component of TMCs and the size of CSQDs. We hope this work would be useful for the study of the phonon-related photoelectric properties in CSQDs consisting of TMCs.
Identify Severity Bug Report with Distribution Imbalance by CR-SMOTE and ELM
Authors: Guo Shikai , Chen Rong , Li Hui , Zhang Tianlun , Liu Yaqing
Published: March 2019

Manually inspecting bugs to determine their severity is often an enormous but essential software development task, especially when many participants generate a large number of bug reports in a crowdsourced software testing context. Therefore, boosting the capabilities of methods of predicting bug report severity is critically important for determining the priority of fixing bugs. However, typical classification techniques may be adversely affected when the severity distribution of the bug reports is imbalanced, leading to performance degradation in a crowdsourcing environment. In this study, we propose an enhanced oversampling approach called CR-SMOTE to enhance the classification of bug reports with a realistically imbalanced severity distribution. The main idea is to interpolate new instances into the minority category that are near the center of existing samples in that category. Then, we use an extreme learning machine (ELM) — a feedforward neural network with a single layer of hidden nodes — to predict the bug severity. Several experiments were conducted on three datasets from real bug repositories, and the results statistically indicate that the presented approach is robust against real data imbalance when predicting the severity of bug reports. The average accuracies achieved by the ELM in predicting the severity of Eclipse, Mozilla, and GNOME bug reports were 0.780, 0.871, and 0.861, which are higher than those of classifiers by 4.36%, 6.73%, and 2.71%, respectively.
Document Summarization Using Sentence-Level Semantic Based on Word Embeddings
Authors: Al-Sabahi Kamal , Zuping Zhang
Published: March 2019

In the era of information overload, text summarization has become a focus of attention in a number of diverse fields such as, question answering systems, intelligence analysis, news recommendation systems, search results in web search engines, and so on. A good document representation is the key point in any successful summarizer. Learning this representation becomes a very active research in natural language processing field (NLP). Traditional approaches mostly fail to deliver a good representation. Word embedding has proved an excellent performance in learning the representation. In this paper, a modified BM25 with Word Embeddings are used to build the sentence vectors from word vectors. The entire document is represented as a set of sentence vectors. Then, the similarity between every pair of sentence vectors is computed. After that, TextRank, a graph-based model, is used to rank the sentences. The summary is generated by picking the top-ranked sentences according to the compression rate. Two well-known datasets, DUC2002 and DUC2004, are used to evaluate the models. The experimental results show that the proposed models perform comprehensively better compared to the state-of-the-art methods.
A sharp estimate for Neumann eigenvalues of the Laplace–Beltrami operator for domains in a hemisphere
Authors: Benguria Rafael D. , Brandolini Barbara , Chiacchio Francesco
Published: March 2019

Here, we prove an isoperimetric inequality for the harmonic mean of the first [Formula: see text] non-trivial Neumann eigenvalues of the Laplace–Beltrami operator for domains contained in a hemisphere of [Formula: see text].
Low energy configurations of topological singularities in two dimensions: A Γ-convergence analysis of dipoles
Authors: De Luca Lucia , Ponsiglione Marcello
Published: March 2019

This paper deals with the variational analysis of topological singularities in two dimensions. We consider two canonical zero-temperature models: the core radius approach and the Ginzburg–Landau energy. Denoting by [Formula: see text] the length scale parameter in such models, we focus on the [Formula: see text] energy regime. It is well known that, for configurations whose energy is bounded by [Formula: see text], the vorticity measures can be decoupled into the sum of a finite number of Dirac masses, each one of them carrying [Formula: see text] energy, plus a measure supported on small zero-average sets. Loosely speaking, on such sets the vorticity measure is close, with respect to the flat norm, to zero-average clusters of positive and negative masses. Here, we perform a compactness and [Formula: see text]-convergence analysis accounting also for the presence of such clusters of dipoles (on the range scale [Formula: see text], for [Formula: see text]), which vanish in the flat convergence and whose energy contribution has, so far, been neglected. Our results refine and contain as a particular case the classical [Formula: see text]-convergence analysis for vortices, extending it also to low energy configurations consisting of just clusters of dipoles, and whose energy is of order [Formula: see text] with [Formula: see text].
Dirichlet spaces of domains bounded by quasicircles
Authors: Radnell David , Schippers Eric , Staubach Wolfgang
Published: March 2019

Consider a multiply-connected domain [Formula: see text] in the sphere bounded by [Formula: see text] non-intersecting quasicircles. We characterize the Dirichlet space of [Formula: see text] as an isomorphic image of a direct sum of Dirichlet spaces of the disk under a generalized Faber operator. This Faber operator is constructed using a jump formula for quasicircles and certain spaces of boundary values. Thereafter, we define a Grunsky operator on direct sums of Dirichlet spaces of the disk, and give a second characterization of the Dirichlet space of [Formula: see text] as the graph of the generalized Grunsky operator in direct sums of the space [Formula: see text] on the circle. This has an interpretation in terms of Fourier decompositions of Dirichlet space functions on the circle.
A quasi-Hopf algebra for the triplet vertex operator algebra
Authors: Creutzig Thomas , Gainutdinov Azat M. , Runkel Ingo
Published: March 2019

We give a new factorizable ribbon quasi-Hopf algebra [Formula: see text], whose underlying algebra is that of the restricted quantum group for [Formula: see text] at a [Formula: see text]th root of unity. The representation category of [Formula: see text] is conjecturally ribbon equivalent to that of the triplet vertex operator algebra (VOA) [Formula: see text]. We obtain [Formula: see text] via a simple current extension from the unrolled restricted quantum group at the same root of unity. The representation category of the unrolled quantum group is conjecturally equivalent to that of the singlet VOA [Formula: see text], and our construction is parallel to extending [Formula: see text] to [Formula: see text]. We illustrate the procedure in the simpler example of passing from the Hopf algebra for the group algebra [Formula: see text] to a quasi-Hopf algebra for [Formula: see text], which corresponds to passing from the Heisenberg VOA to a lattice extension.
Commuting planar polynomial vector fields for conservative Newton systems
Authors: Nagloo Joel , Ovchinnikov Alexey , Thompson Peter
Published: March 2019

We study the problem of characterizing polynomial vector fields that commute with a given polynomial vector field on a plane. It is a classical result that one can write down solution formulas for an ODE that corresponds to a planar vector field that possesses a linearly independent commuting vector field. This problem is also central to the question of linearizability of vector fields. Let [Formula: see text], where [Formula: see text] is a field of characteristic zero, and [Formula: see text] the derivation that corresponds to the differential equation [Formula: see text] in a standard way. Let also [Formula: see text] be the Hamiltonian polynomial for [Formula: see text], that is [Formula: see text]. It is known that the set of all polynomial derivations that commute with [Formula: see text] forms a [Formula: see text]-module [Formula: see text]. In this paper, we show that, for every such [Formula: see text], the module [Formula: see text] is of rank [Formula: see text] if and only if [Formula: see text]. For example, the classical elliptic equation [Formula: see text], where [Formula: see text], falls into this category.
Random polytopes obtained by matrices with heavy-tailed entries
Authors: Guédon O. , Litvak A. E. , Tatarko K.
Published: March 2019

Let [Formula: see text] be an [Formula: see text] random matrix with independent entries and such that in each row entries are i.i.d. Assume also that the entries are symmetric, have unit variances, and satisfy a small ball probabilistic estimate uniformly. We investigate properties of the corresponding random polytope [Formula: see text] in [Formula: see text] (the absolute convex hull of rows of [Formula: see text]). In particular, we show that [Formula: see text] where [Formula: see text] depends only on parameters in small ball inequality. This extends results of [A. E. Litvak, A. Pajor, M. Rudelson and N. Tomczak-Jaegermann, Smallest singular value of random matrices and geometry of random polytopes, Adv. Math. 195 (2005) 491–523] and recent results of [F. Krahmer, C. Kummerle and H. Rauhut, A quotient property for matrices with heavy-tailed entries and its application to noise-blind compressed sensing, preprint (2018); arXiv:1806.04261]. This inclusion is equivalent to so-called [Formula: see text]-quotient property and plays an important role in compressed sensing (see [F. Krahmer, C. Kummerle and H. Rauhut, A quotient property for matrices with heavy-tailed entries and its application to noise-blind compressed sensing, preprint (2018); arXiv:1806.04261] and references therein).
Semi-linear optimal control problem on a smooth oscillating domain
Authors: Aiyappan S. , Nandakumaran A. K. , Prakash Ravi
Published: March 2019

We demonstrate the asymptotic analysis of a semi-linear optimal control problem posed on a smooth oscillating boundary domain in the present paper. We have considered a more general oscillating domain than the usual “pillar-type” domains. Consideration of such general domains will be useful in more realistic applications like circular domain with rugose boundary. We study the asymptotic behavior of the problem under consideration using a new generalized periodic unfolding operator. Further, we are studying the homogenization of a non-linear optimal control problem and such non-linear problems are limited in the literature despite the fact that they have enormous real-life applications. Among several other technical difficulties, the absence of a sufficient criteria for the optimal control is one of the most attention-grabbing issues in the current setting. We also obtain corrector results in this paper.
On characters of L𝔰𝔩n(−Λ0)-modules
Authors: Bringmann Kathrin , Mahlburg Karl , Milas Antun
Published: March 2019

We use recent results of Rolen, Zwegers, and the first author to study the characters of irreducible (highest weight) modules for the vertex operator algebra [Formula: see text]. We establish asymptotic behaviors of characters for the (ordinary) irreducible [Formula: see text]-modules. As a consequence, we prove that their quantum dimensions are one, as predicted by the representation theory. We also establish a full asymptotic expansion of irreducible characters for [Formula: see text]. Finally, we determine a decomposition formula for the full characters in terms of unary theta and false theta functions which allows us to study their modular properties.
A Self-Adaptive Step Glowworm Swarm Optimization Approach
Authors: Qiong Peng , Liao Yifan , Hao Peng , He Xiaonia , Hui Chen
Published: March 2019

When the basic glowworm swarm optimization (GSO) algorithm optimizes the multi-peak function, the solution accuracy is not high, the later convergence is slow. To solve these problems, the fluorescent factor is introduced to adaptively adjust the step length of the firefly, an adaptive step length firefly optimization algorithm is proposed, this algorithm is an improved self-adaptive step glowworm swarm optimization (ASGSO). In this algorithm, the behavior of glowworms are developed, the step size is dynamically adjusted by the fluorescent factor, the algorithm avoids falling into a local optimum and improves the optimization speed and accuracy. The simulation results show that the improved ASGSO can search for global optimization more quickly and precisely.
General Fuzzy Finite Switchboard Automata
Authors: Kavikumar J. , Tiwari S. P. , Ebas Nur Ain , Shamsidah A. H. Nor
Published: March 2019

The constructions of finite switchboard state automata are known to be an extension of finite automata in the view of commutative and switching state machines. This research incorporated an idea of a switchboard in the general fuzzy automata to introduce general fuzzy finite switchboard automata. The attained output reveals that a strongly connected general fuzzy finite switchboard automaton is equivalent to the retrievable general fuzzy automata. Further, the notion of the switchboard subsystem and strong switchboard subsystem of general fuzzy finite switchboard automata are examined. Finally, the concept of fuzzy topology on general fuzzy finite switchboard automata in terms of these characterisations is formulated.
The Relationship Among Fuzzy Languages, Upper Sets and Fuzzy Ordered Monoids
Authors: Dubey M. K. , Tiwari S. P.
Published: March 2019

The concept of recognizability of a fuzzy language by crisp deterministic fuzzy automaton and monoid is well known. The purpose of the present work is to study the recognizability of fuzzy languages by fuzzy ordered monoids. We show that the upper sets of a given fuzzy ordered monoid play a nice role in such studies. Also, we introduce the syntactic fuzzy ordered monoid of an upper set which recognizes this upper set.
Fields ℚ(d3,ζ3) whose 3-class group is of type (9,3)
Authors: Aouissi Siham , Ismaili Moulay Chrif , Talbi Mohamed , Azizi Abdelmalek
Published: March 2019

Let [Formula: see text] with [Formula: see text] a cube-free positive integer. Let [Formula: see text] be the 3-class group of k. With the aid of genus theory, arithmetic properties of the pure cubic field [Formula: see text] and some results on the 3-class group [Formula: see text], we determine all integers [Formula: see text] such that [Formula: see text].
A new upper bound for numbers with the Lehmer property and its application to repunit numbers
Authors: Burek Dominik , Żmija Błażej
Published: March 2019

A composite positive integer [Formula: see text] has the Lehmer property if [Formula: see text] divides [Formula: see text] where [Formula: see text] is an Euler totient function. In this paper, we shall prove that if [Formula: see text] has the Lehmer property, then [Formula: see text], where [Formula: see text] is the number of prime divisors of [Formula: see text]. We apply this bound to repunit numbers and prove that there are at most finitely many numbers with the Lehmer property in the set [Formula: see text] where [Formula: see text] denotes the highest power of 2 that divides [Formula: see text], and [Formula: see text] is a fixed real number.