bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uniform congruence counting for Schottky semigroups in SL2(𝐙)
Authors: Magee Michael , Oh Hee , Winter Dale 
Published: January 2017

Abstract
Let Γ be a Schottky semigroup in

SL
2

⁢

(
𝐙
)

{\mathrm{SL}_{2}(\mathbf{Z})}

,
and for

q
∈
𝐍

{q\in\mathbf{N}}

, let

Γ
⁢

(
q
)

:=

{

γ
∈
Γ

:

γ
=

e

⁢

(

mod

⁢
q

)

}

{\Gamma(q):=\{\gamma\in\Gamma:\gamma=e~{}(\mathrm{mod}~{}q)\}}

be its congruence subsemigroup
of level q. Let δ denote the Hausdorff dimension of the limit set of Γ.
We prove the following uniform congruence counting theorem
with respect to the family of Euclidean norm balls

B
R

{B_{R}}

in

M
2

⁢

(
𝐑
)

{M_{2}(\mathbf{R})}

of radius R:
for all positive integer q with no small prime factors,

#
⁢

(

Γ
⁢

(
q
)

∩

B
R

)

=

c
Γ

⁢

R

2
⁢
δ

#
⁢

(

SL
2

⁢

(

𝐙
/
q

⁢
𝐙

)

)

+

O
⁢

(

q
C

⁢

R

2
⁢
δ

-
ϵ

)

\#(\Gamma(q)\cap B_{R})=c_{\Gamma}\frac{R^{2\delta}}{\#(\mathrm{SL}_{2}(%
\mathbf{Z}/q\mathbf{Z}))}+O(q^{C}R^{2\delta-\epsilon})

as

R
→
∞

{R\to\infty}

for some

c
Γ

>
0

,

C
>
0

,

ϵ
>
0

{c_{\Gamma}>0,C>0,\epsilon>0}

which are independent of q.
Our technique also applies to give a similar counting result for the continued fractions semigroup of

SL
2

⁢

(
𝐙
)

{\mathrm{SL}_{2}(\mathbf{Z})}

,
which arises in the study of Zaremba’s conjecture on continued fractions.
The use of image analysis in evaluation of the
fibers orientation in Wood-polymer composites
(WPC)
Authors: Bednarz Arkadiusz , Frącz Wiesław , Janowski Grzegorz 
Published: January 2017

Abstract
In this paper a novel way of a digital analysis of
fibers orientation with a five-step algorithmwas presented.
In the study, a molded piece with a dumbbell shape prepared
from wood-polymer composite was used. The injection
molding process was examined in experimental and
numerical way. Based on the developed mathematical algorithm,
a significant compliance of fiber orientation in
different areas of the molded piece was obtained.
The main aim of thisworkwas fiber orientation analysis of
wood-polymer composites. An additional goal of thiswork
was the comparison of the results reached in numerical
analysis with results obtained from an experiment. The results
of this research were important for the scientific and
also from the practical point of view. In future works the
prepared algorithm could be used to reach optimal parameters
of the injection molding process.
Tannin-boron complex as a preservative for 3-ply beech plywoods designed for humid conditions
Authors: Efhamisisi Davood , Thevenon Marie-France , Hamzeh Yahya , Pizzi Antonio , Karimi Ali , Pourtahmasi Kambiz 
Published: January 2017

AbstractBoric acid (BA) effectively controls wood-rotting fungi and termite attack but is readily leached out in outdoor exposure. A newly developed tannin-boron (TB) complex has been investigated to reduce BA leaching and to preserve beech plywood from biological attack. Wood veneers were impregnated with different TB solutions and then bonded with a melamine urea formaldehyde (MUF) adhesive for bond class 2 applications. The formation of a solid hydrophobic TB network on the veneer surfaces partially decreased the tensile shear strength of plywood but the prepared panels met the requirements for bond class 2. The plywood samples made from veneers treated with only BA solutions showed fair resistance against white rot fungus and termite attack, but the durability decreased even after mild leaching tests. The panels made of treated veneers with TB formulations showed instead a high resistance against biological attack after mild leaching and to some extent after severe leaching tests. This depended on the concentration of tannin and BA in the solutions. Favorable results were obtained with 20% tannin in the formulation. The results of the termites feeding choice test were more positive than those obtained by a forced feeding test. The control samples were attacked faster and showed higher weight loss when alternative samples included TB formulations.
A Mumford–Shah-type approach to simultaneous reconstruction and segmentation for emission tomography problems with Poisson statistics
Authors: Klann Esther , Ramlau Ronny , Sun Peng 
Published: January 2017

AbstractWe propose a variational model to simultaneous reconstruction and segmentation in emission tomography. As in the original Mumford–Shah model [27] we use the contour length as penalty term to preserve edge information whereas a different data fidelity term is used to measure the information discrimination between the computed tomography data of the reconstructed object and the observed (or simulated) data. As data fidelity term we use the Kullback–Leibler divergence which originates from the Poisson distribution present in emission tomography. In this paper we focus on piecewise constant reconstructions which is a reasonable assumption in medical imaging. The segmenting contour as well as the corresponding reconstructions are found as minimizers of a Mumford–Shah-type functional over the space of piecewise constant functions. The numerical scheme is implemented by evolving the level-set surface according to the shape derivative of the functional. The method is validated for simulated data with different levels of noise.
Suggestions on how to make suboptimal kidney transplantation an ethically viable option
Authors: Graziano Vincenzo , Buccelli Claudio , Capasso Emanuele , De Micco Francesco , Casella Claudia , Di Lorenzo Pierpaolo , Paternoster Mariano 
Published: January 2017

Abstract
To overcome kidney donation, the pool of potentially eligible donors has been widened by using suboptimal organs harvested from living donors or cadavers. These organs may engender health complications as age, risk factors, and pathologies of donors fail to meet the standard donor criteria.
After examining a wide array of literature on suboptimal kidney transplants, we evidenced two major issues: the lack of standardized terminology and the lack of longterm data on the health outcomes of both suboptimal living donors and recipients. Consequently, surgeons are still unable to provide patients with thorough information to obtain a well-informed consent. Suboptimal kidney transplantation still remains in its experimental stage, thereby raising many ethical and medico-legal concerns.
We suggest that one possible solution to overcome some of the ethical shortcomings of suboptimal kidney donations is to provide living donors and recipients honest, accurate, and thorough information about its health risks. To this aim, we advocate adopting a widely standardized terminology that would embrace the whole concept of suboptimal kidney transplantation, increasing the number of future publications on the health outcomes of living donors and recipients, spurring ethical reflection to improve the experience of suboptimal kidney transplantation and reduce the waiting-list for kidney transplantation.
Cusum analysis for learning curve of videothoracoscopic lobectomy
Authors: Gezer Suat , Avcı Alper , Türktan Mediha 
Published: January 2017

Abstract

Background
Video assisted thoracoscopic (VATS) lobectomy has a demanding learning curve due to its technical complexity and risk of uncontrollable bleeding. We investigated the case number required for gaining technical proficiency by applying cumulative sum analysis on initial VATS lobectomy operations of a single surgeon.

Methods
CALGB definition was used for the definition of VATS lobectomy. The data of the initial cases evaluated and cumulative sum (CUSUM) analysis was applied to duration of the operations and length of hospital stay.

Results
Fifty-eight patients underwent VATS lobectomy. Of those 51 were malignant and 7 were benign. Fifty-five of the procedures were lobectomy, 2 were inferior bi-lobectomy and 1 was left upper lobectomy with chest wall resection. CUSUM analysis reached to proficiency at 27 cases for duration of the operations.

Conclusions
The length of learning curve depends on previous experience of the surgeon on open lobectomy and simpler VATS operations, potential number of VATS lobectomy cases and VATS capability of the surgeon. Depending on these factors, it is possible to obtain technical proficiency with an inferior number of procedures compared with existing literature (50-200).
Unification of all hyperbolic tangent function methods
Authors: Gözükızıl Ömer Faruk , Akçağıl Şamil , Aydemir Tuğba 
Published: January 2017

Abstract
Over the last twenty years, several “different” hyperbolic tangent function methods have been proposed to search solutions for nonlinear partial differential equations (NPDEs). The most common of these methods were the tanh-function method, the extended tanh-function method, the modified extended tanh-function method, and the complex tanh-function method. Besides the excellent sides of these methods, weaknesses and deficiencies of each method were encountered. The authors realized that they did not actually give “very different and comprehensive results”, and some of them are even unnecessary. Therefore, these methods were analysed and significant findings obtained. Firstly, they compared all of these methods with each other and gave the connections between them; and secondly, they proposed a more general method to obtain many more solutions for NPDEs, some of which having never been obtained before, and thus to overcome weaknesses and deficiencies of existing hyperbolic tangent function methods in the literature. This new method, named as the unified method, provides many more solutions in a straightforward, concise and elegant manner without reproducing a lot of different forms of the same solution. Lastly, they demonstrate the effectiveness of the unifed tanh method by seeking more exact solutions of the Rabinovich wave equation which were not obtained before.
The Effects of Pitch Shifts on Delay-Induced Changes in Vocal Sequencing in a Songbird
Authors: Wyatt MacKenzie , Berthiaume Emily A. , Kelly Conor W. , Sober Samuel J. 
Published: January 2017

AbstractLike human speech, vocal behavior in songbirds depends critically on auditory feedback. In both humans and songbirds, vocal skills are acquired by a process of imitation whereby current vocal production is compared to an acoustic target. Similarly, performance in adulthood relies strongly on auditory feedback, and online manipulations of auditory signals can dramatically alter acoustic production even after vocalizations have been well learned. Artificially delaying auditory feedback can disrupt both speech and birdsong, and internal delays in auditory feedback have been hypothesized as a cause of vocal dysfluency in persons who stutter. Furthermore, in both song and speech, online shifts of the pitch (fundamental frequency) of auditory feedback lead to compensatory changes in vocal pitch for small perturbations, but larger pitch shifts produce smaller changes in vocal output. Intriguingly, large pitch shifts can partially restore normal speech in some dysfluent speakers, suggesting that the effects of auditory feedback delays might be ameliorated by online pitch manipulations. Although birdsong provides a promising model system for understanding speech production, the interactions between sensory feedback delays and pitch shifts have not yet been assessed in songbirds. To investigate this, we asked whether the addition of a pitch shift modulates delay-induced changes in Bengalese finch song, hypothesizing that pitch shifts would reduce the effects of feedback delays. Compared with the effects of delays alone, combined delays and pitch shifts resulted in a significant reduction in behavioral changes in one type of sequencing (branch points) but not another (distribution of repeated syllables).
Asymmetries of Dark and Bright Negative Afterimages Are Paralleled by Subcortical ON and OFF Poststimulus Responses
Authors: Li Hui , Liu Xu , Andolina Ian M. , Li Xiaohong , Lu Yiliang , Spillmann Lothar , Wang Wei 
Published: January 2017

Humans are more sensitive to luminance decrements than increments, as evidenced by lower thresholds and shorter latencies for dark stimuli. This asymmetry is consistent with results of neurophysiological recordings in dorsal lateral geniculate nucleus (dLGN) and primary visual cortex (V1) of cat and monkey. Specifically, V1 population responses demonstrate that darks elicit higher levels of activation than brights, and the latency of OFF responses in dLGN and V1 is shorter than that of ON responses. The removal of a dark or bright disc often generates the perception of a negative afterimage, and here we ask whether there also exist asymmetries for negative afterimages elicited by dark and bright discs. If so, do the poststimulus responses of subcortical ON and OFF cells parallel such afterimage asymmetries? To test these hypotheses, we performed psychophysical experiments in humans and single-cell/S-potential recordings in cat dLGN. Psychophysically, we found that bright afterimages elicited by luminance decrements are stronger and last longer than dark afterimages elicited by luminance increments of equal sizes. Neurophysiologically, we found that ON cells responded to the removal of a dark disc with higher firing rates that were maintained for longer than OFF cells to the removal of a bright disc. The ON and OFF cell asymmetry was most pronounced at long stimulus durations in the dLGN. We conclude that subcortical response strength differences between ON and OFF channels parallel the asymmetries between bright and dark negative afterimages, further supporting a subcortical origin of bright and dark afterimage perception.SIGNIFICANCE STATEMENTAfterimages are physiological aftereffects following stimulation of the eye, the study of which helps us to understand how our visual brain generates visual perception in the absence of physical stimuli. We report, for the first time to our knowledge, asymmetries between bright and dark negative afterimages elicited by luminance decrements and increments, respectively. Bright afterimages are stronger and last longer than dark afterimages. Subcortical neuronal recordings of poststimulus responses of ON and OFF cells reveal similar asymmetries with respect to response strength and duration. Our results suggest that subcortical differences between ON and OFF channels help explain intensity and duration asymmetries between bright and dark afterimages, supporting the notion of a subcortical origin of bright and dark afterimages.
Climbing Fibers Control Purkinje Cell Representations of Behavior
Authors: Streng Martha L. , Popa Laurentiu S. , Ebner Timothy J. 
Published: January 2017

A crucial issue in understanding cerebellar function is the interaction between simple spike (SS) and complex spike (CS) discharge, the two fundamentally different activity modalities of Purkinje cells. Although several hypotheses have provided insights into the interaction, none fully explains or is completely consistent with the spectrum of experimental observations. Here, we show that during a pseudo-random manual tracking task in the monkey (Macaca mulatta), climbing fiber discharge dynamically controls the information present in the SS firing, triggering robust and rapid changes in the SS encoding of motor signals in 67% of Purkinje cells. The changes in encoding, tightly coupled to CS occurrences, consist of either increases or decreases in the SS sensitivity to kinematics or position errors and are not due to differences in SS firing rates or variability. Nor are the changes in sensitivity due to CS rhythmicity. In addition, the CS-coupled changes in encoding are not evoked by changes in kinematics or position errors. Instead, CS discharge most often leads alterations in behavior. Increases in SS encoding of a kinematic parameter are associated with larger changes in that parameter than are decreases in SS encoding. Increases in SS encoding of position error are followed by and scale with decreases in error. The results suggest a novel function of CSs, in which climbing fiber input dynamically controls the state of Purkinje cell SS encoding in advance of changes in behavior.SIGNIFICANCE STATEMENTPurkinje cells, the sole output of the cerebellar cortex, manifest two fundamentally different activity modalities, complex spike (CS) discharge and simple spike (SS) firing. Elucidating cerebellar function will require an understanding of the interactions, both short- and long-term, between CS and SS firing. This study shows that CSs dynamically control the information encoded in a Purkinje cell's SS activity by rapidly increasing or decreasing the SS sensitivity to kinematics and/or performance errors independent of firing rate. In many cases, the CS-coupled shift in SS encoding leads a change in behavior. These novel findings on the interaction between CS and SS firing provide for a new hypothesis in which climbing fiber input adjusts the encoding of SS information in advance of a change in behavior.
A ‘silent’ skull metastatic follicular thyroid carcinoma mimicking as a benign scalp tumor in a pregnant woman
Authors: Huang Tsung-Chun , Cheng Yu-Kai , Chen Tsung-Wei , Hsu Yung-Chang , Liu En-Wei , Chen Hsin-Han 
Published: January 2017

Summary
Thyroid cancer with cranial metastasis in a pregnant woman is very rare. In the literature, most cases are diagnosed early from neurogenic signs or symptomatic thyroid gland. Pregnancy also contributes to a hesitation toward early surgical and medical treatments. We reported a scalp tumor in a physically healthy 37-year-old pregnant female with a follicular thyroid carcinoma (FTC) with lung, bone and cranial metastasis in initial presentation. Silent neurogenic and physical examinations make an early diagnosis very challenging. Resection of scalp and intracranial tumor, a thyroidectomy, post-operative radioactive iodine therapy and tyrosine kinase inhibitors were employed as treatment. The scalp tumor was confirmed as a metastatic follicular thyroid carcinoma via positive immunoreactivity for thyroglobulin and thyroid transcription factor 1 in tumor cells. Blood examination revealed an elevated thyroglobulin level (>5335 ng/mL). The patient was discharged without any neurological deficit. An asymptomatic scalp tumor in a pregnant woman with a normal thyroid disease history needs differential diagnosis from intracranial origin. Rapid progression and an elevated thyroglobulin level are the indicators that further image study is needed. Aggressive surgical excision of resectable thyroid gland and metastatic tumor are essential for a longer survival rate. There is nothing to indicate that a post-partum operation will worsen prognosis.

Learning points:

Follicular thyroid cancer with cranial metastasis in initial presentation can be asymptomatic.

Follicular thyroid cancer with cranial metastasis in a pregnant woman can be treated after delivery.

Rapid enlargement of scalp tumor is indicated for further image study even in a patient without any neurological deficit.
Micropolítica escolar y el liderazgo directivo en la escuela
Authors: Rodríguez Revelo Elsy 
Published: January 2017

El presente trabajo analiza la micropolítica de la escuela para conocer la organización de cada centro en particular, así como los conflictos que se generan entre sus miembros. En este escenario, el liderazgo directivo cobra mayor importancia, pues permite fomentar el diálogo y la búsqueda de consensos. Esta dinámica política guarda estrecha relación con la estructura macro de orden jerárquico, racional y lineal. Por lo tanto, estudiarla supone llegar al núcleo de la vida institucional, develar los motivos ocultos que originan sus conflictos, descubrir su base constitutiva, sus juegos de intereses y la manera en que el poder se nutre bajo el paraguas de las normativas y es matizado por sus protagonistas. No obstante, las luchas de poder por intereses comunes o particulares dan lugar a la formación de grupos o coaliciones en defensa de sus objetivos. Considerando lo expuesto, el objetivo de este texto es presentar un breve ensayo como resultado de una revisión bibliográfica relacionada con el tema en cuestión (liderazgo y micropolítica). Esta misma se confronta con opiniones, presentadas a modo de ejemplos empíricos, de miembros de la comunidad educativa de tres centros públicos de la ciudad de Zaragoza (España), obtenidas a través de entrevistas etnográficas. Este grupo heterogéneo consta de: tres directores, tres profesores, tres padres de familia, un jefe de estudios y tres estudiantes. La confrontación de criterios entre las fuentes consultadas y los juicios de los sujetos informantes revelan que el liderazgo del director, en caso de existir, juega un papel importante para impulsar el diálogo en los centros educativos, ya que el líder actúa como dinamizador de la participación y como mediador en la búsqueda de consensos entre distintas posturas en beneficio colectivo, sin que esto suponga, para el director escolar, perder auctoritas y potestas.
LOS PROGRAMAS DE ENRIQUECIMIENTO: DESARROLLO INTEGRAL DE LAS ALTAS CAPACIDADES
Authors: Pomar Tojo Carmen Mª , Calviño Santos Guillermo , Irimia Nores Andrea , Rodríguez Cao Luis , Reyes Quintela Laura 
Published: January 2017

Abstract."ENRICHMENT PROGRAMS: COMPREHENSIVE DEVELOPMENT OF HIGH ABILITY"A satisfactory response to the unique needs of high ability students is an ongoing concern for education professionals. The educational intervention offers possible answers, including enrichment, which aims to provide more depth and richness in learning through the change in the depth of content and methodology. The project is a QVO extracurricular enrichment program, by expanding knowledge, developing strategies and skills, and promoting various attitudes, especially those related to socialization and affection. In QVO intellectual potential is stimulated, cooperative attitudes, social and communication skills, emotional intelligence and team work. Taking cinema as an educational tool, QVO provides a space for innovative learning opportunities and collaborative creation.Keywords: Educational Intervention, High Abilities, Enrichment, Emotional Intelligence, Team work.Resumen.La respuesta satisfactoria a las necesidades únicas de los alumnos con altas capacidades es una preocupación constante para los profesionales de la educación. La intervención educativa nos ofrece alternativas de respuesta, entre ellas el enriquecimiento, encaminado a ofrecer aprendizajes más ricos y variados a través de la modificación en la profundidad del contenido y de la metodología empleada. El proyecto QVO es un programa de enriquecimiento extracurricular, supone la ampliación de conocimientos, el desarrollo de estrategias y destrezas, y la promoción de actitudes diversas, especialmente las referidas a la socialización y a la afectividad. En QVO se estimula el potencial intelectual, las actitudes de cooperación, las habilidades sociales y de comunicación, la inteligencia emocional y el trabajo en equipo. Tomando el cine como vía e instrumento educativo, QVO proporciona un espacio de novedosas oportunidades de aprendizaje y de creación colaborativa.Palabras clave: Intervención Educativa, Altas Capacidades, Enriquecimiento, Inteligencia Emocional, Trabajo en Equipo.