bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrosigmoid Transtentorial Approach Compared to Traditional Transpetrosal Approaches for the Resection of Petroclival Meningiomas: A Case-Control Study
Authors: Jha Ribhu T. , McBride Paul , Zavadskiy Gleb , van Loveren Harry R. , Agazzi Siviero 
Published: June 2020

Abstract
Background Transpetrosal approaches have become standard technique for resection of petroclival meningiomas (PCM). The retrosigmoid craniotomy has also been extensively studied as an alternative approach. The need to resect the tentorium at the end of a retrosigmoid approach has been described, but the upfront transtentorial variation of the retrosigmoid craniotomy has never been described nor evaluated in detail as a possible alternative to the standard petrosectomy approaches.
Objective This study was aimed to directly compare the transpetrosal approaches to the retrosigmoid transtentorial approach (RSTTA) in terms of degree of resection, duration of surgery, and estimated blood loss (EBL).
Methods A retrospective case-control study of patients who underwent resection of PCM between January 2014 and December 2018 was performed. Patients in the two surgical approach groups were matched for age and tumor location. The primary measured outcomes were duration of surgery, EBL, extent of resection, length of postoperative hospital stay, and complications. Data analysis was performed using analysis of variance (ANOVA), multivariate analysis of variance (MANOVA), and analysis of covariance (ANCOVA) tests.
Results Thirteen patients had microsurgical resection of PCM at our center between January 2014 and December 2018. Nine patients underwent a transpetrosal approach and four patients underwent RSTTA. The average duration of surgery was shorter in the RSTTA group (425 vs. 525.4 minutes) and had less blood loss (94 vs. 425 mL). Extent of resection was comparable between the groups.
Conclusion The RSTTA appears to be a safe and efficient technique for resecting PCMs and in selected cases a valid alternative to standard petrosectomies approaches.
Advanced Endoscopic Endonasal Approach to the Pterygopalatine Fossa and Orbit: The Endoscopic Tri-port Approach
Authors: Omura Kazuhiro , Nomura Kazuhiro , Mori Ryosuke , Ishii Yudo , Tanaka Yasuhiro , Otori Nobuyoshi , Kojima Hiromi 
Published: June 2020

Abstract
Objective The pterygopalatine fossa (PPF) is a narrow space situated posterior to the maxillary sinus. While external approaches have been used to treat tumors of the PPF, recent endoscopic approaches have become favored as an alternative; we developed an endoscopic tri-port approach, which provides wide surgical corridor with minimal invasion, for PPF. This report aims to introduce and verify the new approach.
Design Case series.
Setting A tertiary referral hospital.
Participants We reviewed 11 patients with PPF or orbital tumors who were treated with the endoscopic tri-port approach.
Main Outcome Measures Accessing tri-port approach's effects and limitations.
Results When the tumor was located in the PPF or orbit without intracranial invasion, en bloc resection was achieved in six patients. With the exception of one patient, the nasal septum was preserved if not used for skull base reconstruction. If not invaded by a tumor or necessary for reconstruction, the inferior and middle turbinates were preserved.
Conclusion The endoscopic tri-port approach provides an excellent surgical view and wide corridor and not requires an external approach, including a gingival incision.
Covid-19 and Pregnancy: An Overview
Authors: Castro Pedro , Matos Ana Paula , Werner Heron , Lopes Flávia Paiva , Tonni Gabriele , Araujo Júnior Edward 
Published: June 2020

AbstractSince the World Health Organization (WHO) declared coronavirus infection (COVID-19) a Public Health Emergency of International Concern in January 2020, there have been many concerns about pregnant women and the possible effects of this emergency with catastrophic outcomes in many countries. Information on COVID-19 and pregnancy are scarce and spread throughout a few case series, with no more than 50 cases in total. The present review provides a brief analysis of COVID-19, pregnancy in the COVID-19 era, and the effects of COVID-19 on pregnancy.
The Clinical Dilemma of Autism Spectrum Disorder Diagnosis in a Child with 9p Deletion
Authors: Karba Brendan E. , Lemay Jean-Francois , McLeod Scott A. 
Published: June 2020

AbstractWe reported on a 3-year-old girl child patient with the presence of trigonocephaly, broad nasal bridge, flattened occiput, and midface hypoplasia. Formal assessment of her development profile demonstrated expressive and receptive language delays, fine and gross motor delays, and no imaginative or symbolic representative play. Investigation of the etiology of her developmental delays revealed a genetic diagnosis of a 9p24 deletion by chromosomal microarray analysis. The possibility of an additional co-occurring disorder of autism spectrum disorder (ASD) was also raised by a referring clinician. This case report highlighted the clinical dilemma of diagnosing ASD in those with existing genetic syndromes.
A minimalist approach to the syntax of p
Authors: Real-Puigdollers Cristina 
Published: June 2020

Abstract
This paper proposes a minimalist analysis of locative prepositions in Central Catalan, from a comparative perspective.
Specifically, I claim that certain semantic and syntactic properties that are usually considered part of the field of the extended
projection of PPs in cartographic approaches (categories like Place, Degree, K, and AxPart, for example) are in fact properties of the DP in
the complement of a preposition. This claim takes the view that adpositions are a functional projection that relates two DPs, the Figure and
the Ground, and not a lexical head that projects a functional domain on its own, as Ns, Vs or As (cf. den Dikken 2010; Koopman 2000). The final part of the paper proposes a model to account
for the variation that locative prepositions exhibit across Romance languages following the Conjecture of Borer (1984) (known as the Borer-Chomsky Conjecture since Baker 2008).
More precisely, I propose a model in which microparametric differences among Romance simple locative prepositions depend on the particular
composition of features in p.
On the encoding of negation by Source prefixes and the satellite-/verb-framed distinction
Authors: Gibert-Sotelo Elisabeth 
Published: June 2020

AbstractThis paper deals withTalmy’s (2000)typological distinction between satellite- and verb-framed systems by comparing the expression of negative meaning through Source prefixes in Latin and Spanish complex verbs. In particular, the claim is made that the different scope relations established between the Source prefixes and the verb root in each language are the reflection of their different typological nature. The core proposal is that Latin Source prefixes lexicalize a Path head that defines a phase, whereas the Path head lexicalized by the Spanish Source prefix is not phase-defining. This has consequences on the timing of Spell-Out as well as on the position in which roots are merged, which naturally accounts for the distinct lexicalization patterns shown by these prefixed constructions in both languages. The negative meaning of Source prefixes, in turn, is derived from the context in which they are embedded.
Nudges against pandemics: Sweden’s COVID-19 containment strategy in perspective
Authors: Pierre Jon 
Published: June 2020

ABSTRACT
Sweden’s strategy to contain the COVID-19 pandemic stands out internationally as more liberal in terms of not ordering a complete lockdown of society. Sweden kept its primary schools, daycare centers and industries largely open. The government financially supported furloughed workers and increased its support to regional and local governments delivering healthcare and elderly care. However, the death toll in Sweden which passed 4000 by late May 2020 stands in stark contrast to those of other, comparable countries, raising questions about the design of the strategy, and its appropriateness. The paper argues that key assumptions sustaining the strategy, for instance that symptom-free people do not carry, and cannot transmit the Coronavirus, or that local and regional government staff had the necessary training and equipment to tackle the pandemic, along with problems associated with coordinating a decentralized healthcare system, may explain the poor performance of the Swedish containment strategy.
Policy capacity and Singapore’s response to the COVID-19 pandemic
Authors: Woo J J 
Published: June 2020

ABSTRACTDespite its excellent public healthcare system and efficient public administration, Singapore has been severely affected by the COVID-19 pandemic. While fatalities in the city-state remain low and contact tracing efforts have been largely successful, it has nonetheless experienced high rates of infection and the emergence of large infection clusters in its foreign worker dormitories. This paper analyses this dual-track policy outcome – low fatalities but high infection rates – from a policy capacity perspective. Specifically, the policy capacities that had contributed to Singapore’s low fatality rates and effective contact tracing are identified while the capacity deficiencies that may have caused its high rates of infection are discussed. In doing so, I argue that the presence of fiscal, operational and political capacities that were built up after the SARS crisis had contributed to Singapore’s low fatality rate and contact tracing capabilities while deficiencies in analytical capacities may explain its high infection rate.
Using Möbius strip to describe non-integral spin of
electrons
Authors: Raj Arindam 
Published: June 2020

Abstract
This article presents a simple demonstration that can be used in high
school/introductory college level courses to explain the meaning of
½-spin of fermions like electrons. One can use a simple-to-construct
Möbius strip to distinguish 2π and 4π rotations of a point moving on
the strip. This idea can then be extended to a pointer/arrow (in classroom
settings, say a pen representing a classical analogue to the intrinsic spin
vector), to show how a 4π rotation is needed to return the pointer, to its
initial configuration with respect to the strip.
Low resistance n-contact for UVC LEDs by a two-step plasma etching process
Authors: Cho H K , Kang J H , Sulmoni L , Kunkel K , Rass J , Susilo N , Wernicke T , Einfeldt S , Kneissl M 
Published: June 2020

Abstract
The impact of plasma etching on the formation of low-resistance n-contacts on the AlGaN:Si current spreading layer during the chip fabrication of ultraviolet light-emitting diodes (UV
LEDs) emitting at 265 nm is investigated. A two-step plasma etching process with a first rapid etching using BCl3/Cl2 gas mixture and a second slow etching step using pure Cl2 gas has been developed. The etching sequence provides smooth mesa side-walls and an n-AlGaN surface with reduced surface damage. Ohmic n-contacts with a contact resistivity of 3.5 × 10−4 Ωcm2 are obtained on Si-doped Al0.65Ga0.35N layers and the operating voltages of the UVC LEDs were reduced by 2 V for a current of 20 mA.
Instability and fingering of interfaces in growing tissue
Authors: Büscher Tobias , Diez Angel L , Gompper Gerhard , Elgeti Jens 
Published: June 2020

Abstract
Interfaces in tissues are ubiquitous, both between tissue and environment as well as between populations of different cell types. The propagation of an interface can be driven mechanically. Computer simulations of growing tissues are employed to study the stability of the interface between two tissues on a substrate. From a mechanical perspective, the dynamics and stability of this system is controlled mainly by four parameters of the respective tissues: (i) the homeostatic stress (ii) cell motility (iii) tissue viscosity and (iv) substrate friction. For propagation driven by a difference in homeostatic stress, the interface is stable for tissues which differ in their substrate friction even for very large differences of homeostatic stress; however, it becomes unstable above a critical stress difference when the tissue with the larger homeostatic stress has a higher viscosity. A small difference in directed bulk motility between the two tissues suffices to result in propagation with a stable interface, even for otherwise identical tissues. Larger differences in motility force, however, result in a finite-wavelength instability of the interface. Interestingly, the instability is apparently bound by nonlinear effects and the amplitude of the interface undulations only grows to a finite value in time.
Physics and Humanity: the advancement of women in physics at universities
Authors: Gledhill I M A 
Published: June 2020

Abstract
The physics community of practice has been active at many levels in promoting the advancement of women. However, the percentages of women in university departments remain generally lower in physics than in the life sciences. Arguments relating to teaching and research loads and work-life balance are comparable in these disciplines. This paper addresses the questions of why the advancement of women is relatively slow in physics, and why comparative numbers return to their former levels at the conclusion of initiatives to improve gender balance. Several useful concepts and recent changes are summarised. It is suggested that two relevant dominant factors that differ across these fields are perceived gender bias in the fields, and belief that innate talent is a prerequisite, combined with the stereotype that women do not possess this talent. Two global projects are cited, one of which is currently in progress.
Informal physics teaching for a better society: a mooc-based and context-driven experience on learning radioactivity
Authors: Pizzolato N , Persano Adorno D 
Published: June 2020

Abstract
The general objective of teaching physics is to provide the learners with useful knowledge, in terms of both interdisciplinary scientific concepts and practical problem-solving skills. In this work, we report the experimental evidence, collected during a first year physics class in an upper secondary technical school, for the urgent necessity to adopt an informal and inquiry-based strategy to teach physics effectively, in particular to all those students living in degraded socio-economic environments. Within the pedagogical framework of “Learning by Doing” and the paradigm “Learning by Teaching”, we have explored the benefits of the students’ participation to an informal ICT-based and inquiry-driven learning experience about radioactivity. Subsequently, the same students attended, as scientific communicators, a national science exhibition where the majority of the secondary schools in the region presents their scientific exhibits. About three months after the participation to the scientific exhibition, the students answered to a questionnaire about radioactivity. Their answers have been analysed in comparison with those provided by a control group of students who attended a traditional lecture-based instruction. A significant improvement in the memorization of the main aspects concerning a radioactive decay, such as the definition of isotope, particle and electromagnetic radiation, the understanding of the radioactivity process at microscopic level, as well as a stronger view of the useful aspect of radioactivity in the everyday life have been definitely achieved by the students involved in this study.
Ladder Operators for the Rosen-Morse System Through Classical Analogy
Authors: Delisle-Doray L , Hussin V 
Published: June 2020

Abstract
In quantum mechanics, ladder operators allow to connect the eigenstates of a system together. Ladder functions are algebraically analog objects defined in the framework of classical hamiltonian physics. For a class of exactly solvable one dimensional Hamiltonians, both the ladder operators and ladder functions take a simple form and there is a close similarity between them. In this work, we show how the analogy extends to the case of the Rosen-Morse Hamiltonian, for which the ladder functions have a more complicated structure. We compute a form for the ladder operators, based on the ladder functions of the system and we analyse the correspondences between both cases. Physical mean values are also obtained as a byproduct of the construction.
Ermakov-Lewis Invariant for Two Coupled Oscillators
Authors: Ramos-Prieto I , Urzúa A R , Fernández-Guasti M , Moya-Cessa H M 
Published: June 2020

Abstract
We show that two coupled time dependent harmonic oscillators with equal frequencies have an invariant that is a generalization of the Ermakov-Lewis invariant for the single time dependent harmonic oscillator.
On Self-Adjointness of 3D—Dirac Operators with Singular Potentials
Authors: Rabinovich V 
Published: June 2020

Abstract
We consider the Dirac operator on ℝ3,

D

A
,
Φ
,

Q
s

=

∑

j
=
1

3

α
j

(
i

∂

x
j

+

A
j

(
x
)
)

+

α
0

m

−

Φ
(
x
)

I
4

+

Q
s

, with magnetic potential
A
(x) = (A
1(x), A
2(x), A
3(x))) and electrostatic potential Φ(x), where αj,j = 0, 1, 2, 3 are the Dirac matrices, Qs
= ΓδS
is a singular potential where δS
is the Dirac δ—function with support on an enough smooth surface S ⊂ ℝ3 divided ℝ3 on two open domains Ω+, Ω− with common unbounded boundary S, and Γ is 4 × 4 matrix. We associate with the formal Dirac operator D

A
, Φ, Qs

the unbounded in the Hilbert space L
2(ℝ3, ℂ4) operator D with domain defined by some interaction conditions on the surface S. The purpose of the paper is to give conditions of the self-adjointness of the operator D.
Multimode Two-Dimensional PT-Symmetric Waveguides
Authors: Contreras-Astorga A , Jakubský V 
Published: June 2020

Abstract
In this article, we apply a time-dependent Darboux transformation for the construction of PT-symmetric multimode optical waveguides where the non-separable complex fluctuations of the refractive index confine guided modes. We focus on a family of settings based on the hyperbolic Pöschl-Teller potential well. We show that the transformed systems have a “missing” state, an extra guided mode whose analog does not exist in the original system.
Featuring Causal Order in Teleportation With Two Quantum Teleportation Channels
Authors: Cardoso-Isidoro C , Delgado F 
Published: June 2020

Abstract
Causal order can improve the quantum information transmission in teleportation due a noisy entangled resource being present in it by using additionally an appropriate measurement state on the control state ruling the causal order. In this work, we get analytically the fidelity for the entire process under an arbitrary initialization of such control state and performing an optimal measurement on it, thus obtaining a perfect teleportation. We also analyse other values characterizing the imperfect entangled state where a perfect teleportation can not be reached. Notably, we determine that the best fidelity does not depend on the preparation of the control state but instead on the imperfect initial entangled resource.
Analysis of a Stratified Quantum Waveguide with Interactions at Interface Planes
Authors: Conde-Vazquez R , Barrera-Figueroa V , Rabinovich V S 
Published: June 2020

Abstract
In this paper we consider a quantum waveguide that consists of three strata ∏0 = {(x, x
3) ∈ ℝ3 : x
3 < 0}, ∏0,h
= {(x, x
3) ∈ ℝ3 : 0 < x
3 < h }, ∏
h
= {(x, x
3) ∈ ℝ3 : x
3 > h }, where x = (x
1, x
2) ∈ ℝ2. A potential of the form q = qr
+ qs
is established in this structure, where qr
is a regular bounded potential depending on only the coordinate x
3, and qs
is the singular potential qs
= α
1
δ (x
3) + β
1
δ´ (x
3) + α
2
δ (x
3 – h) + β
2
δ´ (x
3 – h) with support at the planes x
3 = 0 and x
3 = h. The Green’s function of the waveguide is constructed as an expansion involving the eigenfunctions and generalized eigenfunctions of an auxiliary one-dimensional Schrödinger operator. The asymptotic analysis of the Green’s function is carried out by means of the stationary phase method. This gives the leading contribution of the Green’s function far from the point source. Finally some numerical examples are considered for the application of the present analysis.
Wireless optical system using amplitude modulation with GNU radio on a Raspberry Pi
Authors: Zapata R E , Martínez R A , López F E , Góez G D 
Published: June 2020

Abstract
Visible light communication system arises to create wireless links using light-emitting diode luminaires. The literature reports multiple works in visible light communication using different development tools. However, most are based on signal processors, field-programmable gate Arrays and proprietary software to develop the algorithms. This paper presents a wireless optical communication system using amplitude modulation on both hardware and free software tools. An algorithm for amplitude modulation/demodulation in GNU Radio installed on the Raspberry Pi development card was created. Additionally, an optical transmitter based on a white light-emitting diode and a receiver with a solar panel was designed. Communication experiments were performed based on the distance of the system link. The results report that the optimal response of amplitude modulation/demodulation was achieved with a solar panel response of --68 dBmV at maximum distance of 3 m between transmitter and receiver at usual illumination levels, and the potential to use free hardware and software tools in the implementation and analysis of optical wireless communication systems.
Long-period fiber grating sensors fabrication at high-frequency carbon dioxide laser pulses
Authors: Rojas J F , Valencia S , Montoya-Cardona J A , Galvis J L , Gomez-Cardona N D 
Published: June 2020

Abstract
In this work, long-period fiber grating sensors are written by using a point to point technique based on the thermal shock of focused high-frequency carbon dioxide laser pulses at several kilohertz. The thermal response of each long-period fiber grating was characterized by using a Peltier module based control system. The average sensitivity of the sensor was calculated to be ∼ 0.079 nm/°C. The used technique facilitates to obtain compact and sturdy long-period fiber gratings, with low insertion loss and low-level back reflection.
An image fusion method based on the Hermite transform applied to nuclear medicine and x-ray tomographic modalities
Authors: Barba-J L , Vargas-Quintero L , Calderon J A , Torres Moreno C 
Published: June 2020

Abstract
Image fusion is an interesting processing task that has reached great significance for medical image analysis. In general, the combination of medical images coming from different modalities is a common practice that significantly helps in the process of diagnosis and detection of several diseases. In this work, we present a novel method for image fusion based on the Hermite transform which consists of a powerful tool that projects an input image into the space defined by the Hermite polynomials. The proposed approach is performed in three main stages. 1) The HT is applied to the input images, 2) The resulting coefficients are fused using the maximum and average intensity rules, and 3) The inverse HT is performed to obtain the final fused image. The method is applied and evaluated using several single photon emission computed tomography and computed tomography studies taken for bone structures. Typical metrics were used to assess the proposed framework. We demonstrate that this methodology is able to efficiently fuse images coming from different modalities, particularly, nuclear medicine and x-ray tomographic techniques. With the Hermite transform, image features are successfully extracted which becomes fundamental in the process of image fusing.