bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of the evolution of end-tidal carbon dioxide within chest compression pauses to detect restoration of spontaneous circulation
Authors: Gutiérrez Jose Julio , Leturiondo Mikel , Ruiz de Gauna Sofía , Ruiz Jesus María , Azcarate Izaskun , González-Otero Digna María , Urtusagasti Juan Francisco , Russell James Knox , Daya Mohamud Ramzan 
Published: May 2021

Background
Measurement of end-tidal CO2 (ETCO2) can help to monitor circulation during cardiopulmonary resuscitation (CPR). However, early detection of restoration of spontaneous circulation (ROSC) during CPR using waveform capnography remains a challenge. The aim of the study was to investigate if the assessment of ETCO2 variation during chest compression pauses could allow for ROSC detection. We hypothesized that a decay in ETCO2 during a compression pause indicates no ROSC while a constant or increasing ETCO2 indicates ROSC.

Methods
We conducted a retrospective analysis of adult out-of-hospital cardiac arrest (OHCA) episodes treated by the advanced life support (ALS). Continuous chest compressions and ventilations were provided manually. Segments of capnography signal during pauses in chest compressions were selected, including at least three ventilations and with durations less than 20 s. Segments were classified as ROSC or non-ROSC according to case chart annotation and examination of the ECG and transthoracic impedance signals. The percentage variation of ETCO2 between consecutive ventilations was computed and its average value, ΔETavg, was used as a single feature to discriminate between ROSC and non-ROSC segments.

Results
A total of 384 segments (130 ROSC, 254 non-ROSC) from 205 OHCA patients (30.7% female, median age 66) were analyzed. Median (IQR) duration was 16.3 (12.9,18.1) s. ΔETavg was 0.0 (-0.7, 0.9)% for ROSC segments and -11.0 (-14.1, -8.0)% for non-ROSC segments (p < 0.0001). Best performance for ROSC detection yielded a sensitivity of 95.4% (95% CI: 90.1%, 98.1%) and a specificity of 94.9% (91.4%, 97.1%) for all ventilations in the segment. For the first 2 ventilations, duration was 7.7 (6.0, 10.2) s, and sensitivity and specificity were 90.0% (83.5%, 94.2%) and 89.4 (84.9%, 92.6%), respectively. Our method allowed for ROSC detection during the first compression pause in 95.4% of the patients.

Conclusion
Average percent variation of ETCO2 during pauses in chest compressions allowed for ROSC discrimination. This metric could help confirm ROSC during compression pauses in ALS settings.
Use of seat belts among public transport drivers in Tacna, Peru: Prevalence and risk factors
Authors: Miñan-Tapia Armando , Torres-Riveros Gloria S. , Choque-Vargas José , Aycachi-Incacoña Madeleyni , Flores-Valdez Neil , Vargas-Anahua Orlando , Mejia Christian R. 
Published: May 2021

Introduction
There are individuals who still refuse to wear seat belts, despite its effectiveness in reducing morbidity and mortality in road traffic accidents. We aimed to determine the prevalence and risk factors according to the use of seat belts among public transport drivers in Tacna, Peru.

Methodology
This analytical transversal study was carried out among public transport drivers (buses and taxis) in a Peruvian city. Questionnaires were used to evaluate the general and occupational characteristics and the use of seat belts (observed). Descriptive statistics and risk factors were obtained, these latter through generalized linear models.

Results
Of the 460 drivers, 77% used their seat belts, with a difference in use depending on the type of public transport (p<0.001). In the multivariate model, the risk of not using the belt was associated with the following: older age (p<0.001), having complete studies (p<0.001), a higher level/category of driving license (3 categories had p<0.001), having a higher number of previous road traffic accidents (p = 0.011), and received medical attention in that accident (p<0.001), those who reported using a cell phone while driving (p = 0.005), if the co-driver’s belt had 3 anchorage points (p<0.001), and working for > 5 hours that day (p = 0.002). However, male drivers and those who had their belt with 3 anchorage points had greater use (both p<0.001).

Conclusions
One in five drivers did not use a seat belt, and important characteristics of those who did not comply with this traffic law were evaluated to generate control and intervention measures.
Competencias matemáticas: una mirada desde las estrategias de enseñanza en educación a distancia
Authors: Valderrama Martínez Daniel Alberto 
Published: May 2021

El enfoque por competencias se constituye como una alternativa frente a la enseñanza tradicional centrada en la memorización y la mecanización, porque supone la combinación de conocimientos y el desarrollo de habilidades puestos en acción en una situación contextualizada. Dentro de las competencias transversales requeridas para el ejercicio profesional, las matemáticas desempeñan un papel importante al crear habilidades de pensamiento que permiten razonar de manera lógica y eficiente en resolución de problemas o situaciones cotidianas y tomar decisiones de forma eficiente. En educación a distancia, el desarrollo de competencias matemáticas está mediado por el uso de TIC, el deseo por aprender, el autoaprendizaje, el contexto y en el rol del docente, quien conducirá al estudiantado a la consecución de objetivos pertinentes para afrontar problemas. En ese sentido, el presente artículo tiene como objetivo establecer algunos elementos centrados en las competencias matemáticas en educación a distancia que deben considerarse para identificar las estrategias empleadas por los docentes en una institución de educación superior se integran al enfoque por competencias. La metodología utilizada corresponde al enfoque cualitativo de tipo fenomenológico interpretativo, fundamentada en la aplicación de una entrevista semiestructurada. Los resultados muestran que es necesario realizar transformaciones en algunas estrategias docentes.
Inclusión educativa de estudiantes con diversidad funcional visual en clases de ciencias naturales: un análisis desde la política pública
Authors: Castro Castillo Diana Carolina , Tuay Sigua Rosa Nidia 
Published: May 2021

En los últimos años se han emprendido un conjunto de acciones que han posibilitado la inclusión en la escuela, de personas con diversidad funcional visual, ciegos, en los procesos de enseñanza y aprendizaje de las ciencias naturales, los cuales se dan como consecuencia de los movimientos dados a nivel mundial, desde la Declaración sobre la Educación para Todos (Unesco, 1990). En este orden de ideas, algunas instituciones de la ciudad de Bogotá, Colombia, han sido dotadas de recursos físicos y humanos para atender estas comunidades, sin embargo, se hace necesario, mayor reflexión y propuestas teóricas sobre las implicaciones que tiene el abordaje de los objetos de conocimiento de las ciencias y cómo estos deben ser enseñados desde el reconocimiento de las capacidades sensoriales de los estudiantes. En este artículo de investigación se realiza un análisis de algunos documentos de política pública a nivel nacional e internacional relacionados con la enseñanza de la ciencia y su perspectiva de inclusión para estudiantes con diversidad funcional visual y documentos particulares sobre la inclusión educativa. El estudio se enmarca en una tesis del Doctorado Interinstitucional en Educación de la Universidad Pedagógica Nacional.
XXIII Semana de la Enseñanza de La Física. 200 años del Electromagnetismo.
Authors: Mancera Martínez Brian Mateo , Salamanca Bernal Julián Andrés , Hurtado Alejandro 
Published: May 2021

Evento desarrollado del 23 al 27 de noviembre de 2020, en el Proyecto Curricular de Licenciatura en Física, de la Facultad de Ciencias y Educación. Universidad Distrital Francisco José de Caldas, Bogotá, Colombia.
A comienzos de 1820 el físico danés Hans Christian Ørsted descubrió experimentalmente la relación existente entre el magnetismo y la electricidad, publicando su descubrimiento en un corto artículo titulado: Experimenta circa effectum conflictus electrici in acum magneticam. Dando origen al electromagnetismo y a una serie de trabajos de diversos científicos, que culminaron con la unificación, lograda por James Clerk Maxwell, de la electricidad, el magnetismo y la luz como diversas manifestaciones de un mismo fenómeno físico. Trabajo que fue publicado bajo el título de: A Dynamical Theory of the Electromagnetic Field. Se cumplen así 200 años de un descubrimiento que cambiaría la concepción física de la época y potenciaría un desarrollo que aún hoy día continúa.
Los efectos de la pandemia en las universidades y su relevancia en los estudios comparados internacionales
Authors: Arenas Jorge 
Published: May 2021

La vulnerabilidad de las sociedades a consecuencia de la intervención de los humanos en los ecosistemas planetarios, junto con los procesos de la globalización que expanden los impactos de fenómenos locales al resto del mundo, han sido descritos de forma lúcida por el sociólogo alemán Ulrich Beck, quien en su obra clásica “La Sociedad del Riesgo” (1998) advertía ya de la permanente condición de peligro que enfrentan las sociedades modernas, como resultado de la aplicación intensiva del conocimiento en el dominio de la naturaleza. De alguna forma, las previsiones de este autor se tornaron ominosa realidad tras la alerta de la Organización Mundial de la Salud (OMS), el 11 de marzo de 2020, en el sentido de que la humanidad enfrentaba una pandemia de alcances imprevistos como la del COVID-19.
The geometric average of curl-free fields in periodic geometries
Authors: Poelstra Klaas Hendrik , Schweizer Ben , Urban Maik 
Published: May 2021

Abstract
In periodic homogenization problems, one
considers a sequence

(

u
η

)

η

{(u^{\eta})_{\eta}}

of solutions to periodic
problems and derives a homogenized equation for an effective
quantity

u
^

{\hat{u}}

. In many applications,

u
^

{\hat{u}}

is the weak
limit of

(

u
η

)

η

{(u^{\eta})_{\eta}}

, but in some applications

u
^

{\hat{u}}

must
be defined differently. In the homogenization of Maxwell’s
equations in periodic media, the effective magnetic field is
given by the geometric average of the two-scale limit. The notion
of a geometric average has been introduced in [G. Bouchitté, C. Bourel and D. Felbacq,
Homogenization of the 3D Maxwell system near resonances and artificial magnetism,
C. R. Math. Acad. Sci. Paris 347 2009, 9–10, 571–576]; it associates to a
curl-free field

Y
∖

Σ
¯

→

ℝ
3

{Y\setminus\overline{\Sigma}\to\mathbb{R}^{3}}

, where
Y is the periodicity cell and Σ an inclusion, a vector
in

ℝ
3

{\mathbb{R}^{3}}

. In this article, we extend previous definitions to
more general inclusions, in particular inclusions that are not
compactly supported in the periodicity cell. The physical
relevance of the geometric average is demonstrated by various
results, e.g., a continuity property of limits of tangential traces.
Multiplicity and Concentration of Solutions for Kirchhoff Equations with Magnetic Field
Authors: Ji Chao , Rădulescu Vicenţiu D. 
Published: May 2021

Abstract
In this paper, we study the following nonlinear magnetic Kirchhoff equation:

{

-

(

a
⁢

ϵ
2

+

b
⁢
ϵ
⁢

[
u
]

A
/
ϵ

2

)

⁢

Δ

A
/
ϵ

⁢
u

+

V
⁢

(
x
)

⁢
u

=

f
⁢

(

|
u
|

2

)

⁢
u

in
⁢

ℝ
3

,

u
∈

H
1

⁢

(

ℝ
3

,
ℂ
)

,

\left\{\begin{aligned} &\displaystyle{-}(a\epsilon^{2}+b\epsilon[u]_{A/% \epsilon}^{2})\Delta_{A/\epsilon}u+V(x)u=f(\lvert u\rvert^{2})u&&\displaystyle% \phantom{}\text{in }\mathbb{R}^{3},\\ &\displaystyle u\in H^{1}(\mathbb{R}^{3},\mathbb{C}),\end{aligned}\right.

where

ϵ
>
0

{\epsilon>0}

,

a
,
b

>
0

{a,b>0}

are constants,

V
:

ℝ
3

→
ℝ

{V:\mathbb{R}^{3}\rightarrow\mathbb{R}}

and

A
:

ℝ
3

→

ℝ
3

{A:\mathbb{R}^{3}\rightarrow\mathbb{R}^{3}}

are continuous potentials, and

Δ
A

⁢
u

{\Delta_{A}u}

is the magnetic Laplace operator. Under a local assumption on the potential V, by combining variational methods, a penalization technique and the Ljusternik–Schnirelmann theory, we prove multiplicity properties of solutions and concentration phenomena for ϵ small. In this problem, the function f is only continuous, which allows to consider larger classes of nonlinearities in the reaction.
Dimensionally Consistent Preconditioning for Saddle-Point Problems
Authors: Herzog Roland 
Published: May 2021

Abstract
The preconditioned iterative solution of large-scale saddle-point systems is of great importance in numerous application areas, many of them involving partial differential equations.
Robustness with respect to certain problem parameters is often a concern, and it can be addressed by identifying proper scalings of preconditioner building blocks.
In this paper, we consider a new perspective to finding effective and robust preconditioners.
Our approach is based on the consideration of the natural physical units underlying the respective saddle-point problem.
This point of view, which we refer to as dimensional consistency, suggests a natural combination of the parameters intrinsic to the problem.
It turns out that the scaling obtained in this way leads to robustness with respect to problem parameters in many relevant cases.
As a consequence, we advertise dimensional consistency based preconditioning as a new and systematic way to designing parameter robust preconditoners for saddle-point systems arising from models for physical phenomena.
Eisenstein series and the top degree cohomology of arithmetic subgroups of SL
n
/ℚ
Authors: Schwermer Joachim 
Published: May 2021

Abstract
The cohomology

H
*

⁢

(
Γ
,
E
)

{H^{*}(\Gamma,E)}

of a torsion-free arithmetic subgroup Γ of the special linear

ℚ

{\mathbb{Q}}

-group

𝖦
=

SL
n

{\mathsf{G}={\mathrm{SL}}_{n}}

may be interpreted in terms of the automorphic spectrum of Γ. Within this framework, there is a decomposition of the cohomology into the cuspidal cohomology
and the Eisenstein cohomology.
The latter space is decomposed according to the
classes

{
𝖯
}

{\{\mathsf{P}\}}

of associate proper parabolic

ℚ

{\mathbb{Q}}

-subgroups of

𝖦

{\mathsf{G}}

. Each summand

H

{
P
}

*

⁢

(
Γ
,
E
)

{H^{*}_{\mathrm{\{P\}}}(\Gamma,E)}

is built up by Eisenstein series (or residues of such) attached to cuspidal automorphic forms
on the Levi components of elements in

{
𝖯
}

{\{\mathsf{P}\}}

.
The cohomology

H
*

⁢

(
Γ
,
E
)

{H^{*}(\Gamma,E)}

vanishes above the degree given by the cohomological dimension

cd
⁢

(
Γ
)

=

1
2

⁢
n
⁢

(

n
-
1

)

{\mathrm{cd}(\Gamma)=\frac{1}{2}n(n-1)}

.
We are concerned with the internal structure of the cohomology in this top degree. On the one hand, we explicitly describe the associate classes

{
𝖯
}

{\{\mathsf{P}\}}

for which the corresponding summand

H

{
𝖯
}

cd
⁢

(
Γ
)

⁢

(
Γ
,
E
)

{H^{\mathrm{cd}(\Gamma)}_{\mathrm{\{\mathsf{P}\}}}(\Gamma,E)}

vanishes. On the other hand, in the remaining cases of associate classes
we construct various families of non-vanishing Eisenstein cohomology classes which span

H

{
𝖰
}

cd
⁢

(
Γ
)

⁢

(
Γ
,
ℂ
)

{H^{\mathrm{cd}(\Gamma)}_{\mathrm{\{\mathsf{Q}\}}}(\Gamma,\mathbb{C})}

.
Finally, in the case of a principal congruence subgroup

Γ
⁢

(
q
)

{\Gamma(q)}

,

q
=

p
ν

>
5

{q=p^{\nu}>5}

,

p
≥
3

{p\geq 3}

a prime, we give lower bounds for the size of these spaces. In addition, for certain associate classes

{
𝖰
}

{\{\mathsf{Q}\}}

, there is a precise formula for their dimension.
Modification of sodium bicarbonate and its effect on foaming behavior of polypropylene
Authors: Luo Dan , Pei Xianglin , Fu Hai , Yang Xin , Long Siyu , Zhang Linyu , Gong Wei 
Published: May 2021

Abstract
As a potential physical blowing agent, sodium bicarbonate (SB) is environmentally friendly and low in cost, but its low decomposition temperature cannot meet the requirements of polyolefin foam materials. Herein, for enhancing the thermal properties of SB, a modified way was offered to fabricate various SB-based capsules via suspension polymerization. As the modified SB-based capsules, epoxy resin (EP) accompanied with several organic acids was successfully coated on the surface of SB, serving as heat-insulation layer of SB. Various physicochemical characterizations provided reliable evidences for the good coating effect, and the thermal performance of the modified SB was improved. Further, the composite SB capsules were applied for the foaming of polypropylene (PP), and the foaming behavior of the SB-based capsules in PP was significantly improved, with more uniform distribution, smaller cell diameter, and higher cell density. In all, this work fully proved that the coated shells enhanced the thermal properties of SB, and the modified SB capsules significantly improved the foaming quality of foamed PP.
A flexible power management strategy for PV-battery based interconnected DC microgrid
Authors: Panda Mrutunjaya , Devara Vijaya Bhaskar , Salkuti Surender Reddy 
Published: May 2021

Abstract
In this paper, a coordinated power-sharing strategy for interconnected DC-microgrid (DC-MG) is proposed. The DC-MG consists of two subgrids with an interlinking bidirectional DC/DC converter (IBDDC). Each subgrid has a secondary-1 controller based on a state of charge (SoC) balancing based droop control strategy of the battery unit (BU). The proposed droop strategy regulates the DC bus voltage according to the SoC of BU. With the SoC balancing based droop method, BU with higher SoC supplies more power to the microgrid (MG) as compared to low SoC BU. The SoC information of batteries in all subgrids is communicated through low bandwidth communication (LBC). In case of failure of LBC, a secondary-2 controller is implemented for the battery controller to regulate the DC bus voltage considering the SoC of BU. Secondary-2 does not depend on the communication line. Considering the levels of DC bus voltages, a secondary power regulating controller is introduced for IBDDC. Further, a coordinated power control strategy is proposed for distributed generation to avoid overcharging of batteries. The whole system operates in a distributed way without a central controller. The proposed strategy has been verified in MATLAB/Simulink.
z-arcs in the thirty degrees sector
Authors: Movshovich Yevgenya 
Published: May 2021

Abstract
In this detailed study of 3-segment non-convex simple arcs inscribed in the

30
∘

{30^{\circ}}

sector, we show that each such arc of length one fits in the interior of the sector of radius one with the prescribed embedding. We discuss implications of this study for covering problems
involving triangular covers and for the worm problem of Leo Moser.
Synthesis, characterization, and bioevaluation of 99mTc nitrido-oxiracetam as a brain imaging model
Authors: Sanad M. H. , Rizvi S. F. A. , Farag A. B. 
Published: May 2021

Abstract
In this work, the radiotracer [99mTc]nitrido-oxiracetam complex was labeled in the presence of 99mTc-nitrido as a core. In order to get the highest radiochemical purity, many effective factors have been studied such as temperature of the reaction, time of the reaction, the pH of the reaction mixture, substrate amount, and stability to give high percent more than 99%. Finally, biodistribution studies have been indicated the convenience of [99mTc]nitrido-oxiracetam as a new radiotracer that could be used in brain imaging. Giving a maximum uptake of 10.6% at 30 min post injection.
Intracerebral hemorrhage with tentorial herniation: Conventional open surgery or emergency stereotactic craniopuncture aspiration surgery?
Authors: Shi Jing , Zou Xiaohua , Jiang Ke , Tan Li , Wang Likun , Ren Siying , Mao Yuanhong , Yang Chunguang , Wang Weijun , Wu Guofeng , Tang Zhouping 
Published: May 2021

Abstract

Background
To observe the therapeutic effect of conventional decompressive craniectomy with hematoma evacuation and frame-based stereotactic minimally invasive surgery (MIS) for supratentorial intracranial hematoma with herniation.

Methods
One hundred forty-nine patients with hypertensive ICH complicated with tentorial herniation were reviewed and analyzed in the present study. The intracranial hematoma was evacuated by emergency surgery within 6 h after admission. According to the authorized representatives’ wishes and consent, 74 of the 149 patients were treated by conventional decompressive craniectomy followed by hematoma removal, defined as the CDC group, and the remaining 75 patients underwent frame-based stereotactic MIS for ICH evacuation, defined as the MIS group. The intervals between the admission to surgery, the duration of surgery, the amount of iatrogenic bleeding, the occurrence of postoperative rebleeding, and the recovery of neurological functions were compared between the two groups. All patients were followed up for 3 months. Secondary epilepsy, survival in a vegetative state, severe pulmonary complications, mortality, and activities of daily living (ADL) classification were also recorded and compared.

Results
The interval between admission and surgery, the duration of surgery, and intraoperative blood loss in the MIS group were significantly decreased compared to the CDC group. The mortality rate, the rate of rebleeding, prevalence of vegetative state, and severe pulmonary complications in the MIS group were remarkably decreased compared to the CDC group. In the MIS group, the survivors’ (ADL) grade also showed advantages.

Conclusions
In the surgical treatment of hypertensive ICH complicated with tentorial herniation, frame-based stereotactic MIS for ICH showed advantages compared to conventional open surgery.
Pathogenic ACVR1R206H activation by Activin A‐induced receptor clustering and autophosphorylation
Authors: Ramachandran Anassuya , Mehić Merima , Wasim Laabiah , Malinova Dessislava , Gori Ilaria , Blaszczyk Beata K , Carvalho Diana M , Shore Eileen M , Jones Chris , Hyvönen Marko , Tolar Pavel , Hill Caroline S 
Published: May 2021

AbstractFibrodysplasia ossificans progressiva (FOP) and diffuse intrinsic pontine glioma (DIPG) are debilitating diseases that share causal mutations in ACVR1, a TGF‐β family type I receptor. ACVR1R206H is a frequent mutation in both diseases. Pathogenic signaling via the SMAD1/5 pathway is mediated by Activin A, but how the mutation triggers aberrant signaling is not known. We show that ACVR1 is essential for Activin A‐mediated SMAD1/5 phosphorylation and is activated by two distinct mechanisms. Wild‐type ACVR1 is activated by the Activin type I receptors, ACVR1B/C. In contrast, ACVR1R206H activation does not require upstream kinases, but is predominantly activated via Activin A‐dependent receptor clustering, which induces its auto‐activation. We use optogenetics and live‐imaging approaches to demonstrate Activin A‐induced receptor clustering and show it requires the type II receptors ACVR2A/B. Our data provide molecular mechanistic insight into the pathogenesis of FOP and DIPG by linking the causal activating genetic mutation to disrupted signaling.