bluuebunny/crossref_metadata_2025_split huggingface dataset:
MODEL OF FORMATION OF DECISIVE FUNCTION OF COMBINED CORRELATION-EXTREME NAVIGATION SYSTEM USED IN GUIDANCE OF UNMANNED AIRCRAFT
Authors: Sotnikov O. , Tiurina V. 
Published: April 2024

The results of development of formalized model of process of formation of decisive function of combined correlation-extreme navigation system of unmanned aerial vehicles are presented. The development of the model is carried out taking into account the state of the operational and tactical situation, as well as the effect of changing the geometry of the sighting. The peculiarity of the developed model consists in the formation of a decisive function using a set of reference images, which is necessary for the formation of a decisive function, the set of reference images is built taking into account changes in navigation parameters of an unmanned aerial vehicle and angular orientation parameters.
The originality of the formalized model consists in the determined order of formation of the decisive function of the combined correlation-extreme navigation system, which, unlike the known ones, consists in step-by-step determination of coordinates of the reference object by clarifying the navigation parameters of unmanned aerial vehicles with subsequent refinement of the angular orientation parameters according to the following sequence: determining the height of formation of the current image, determining the angles of view and determining the angular orientation parameters. Each of the individual reference images corresponds to its own multidimensional matrix of luminance values of the corresponding pixels or radio-thermal temperature. This takes into account the area of objects located on the sighting surface, which leads to refinement of the coordinates of the reference object in the current image.
Changes in the spatial position and orientation of unmanned aerial vehicles, geometric properties of the sighting surface, as well as taking into account variations in informative features of the sighting surface objects depending on external factors and the influence of the medium on the propagation of signals in the optical and radiometric ranges of waves and obstacles, which will reduce or completely eliminate the discrepancy of coordinates of the reference object to the current image determined in advance in the reference image.
Aplicación de la Estadística Descriptiva al Estudio de Caso: la Prevención del Riesgo Laboral (PRL) en las Empresas de la Ciudad de México y Periferia Después de la Pandemia por Covid-19
Authors: Jiménez Cabrera Roberto 
Published: April 2024

Esta investigación tiene como objetivo reflexionar sobre la Prevención del Riesgo Laboral (PRL) en las empresas de la Ciudad de México después de la pandemia por Covid-19, por ello se llevó a cabo un estudio de caso para mostrar la relevancia de emprender medidas sanitarias relacionadas con PRL después de la pandemia, para tal fin se empleó un enfoque cualitativo llevando a cabo una encuesta a 265 trabajadores para describir la percepción que tienen de las medidas de PRL que se han implementado en sus lugares de empleo. De la encuesta se seleccionaron cinco preguntas relevantes y se sometieron a un estudio estadístico a través de tablas de contingencia donde se aplicaron pruebas de significancia de distribución no simétrica ji-cuadrada para ver la independencia entre el tamaño de las empresas y dicha percepción de las medidas de PRL concluyendo que se requiere de una investigación más específica y con más observaciones para cada percepción. Se destaca la importancia de fomentar la PRL entre todos individuos que están inmersos en las actividades empresariales de las organizaciones productivas. En este proceso se contó con la colaboración de alumnos de la Universidad Rosario Castellanos (URC) de las unidades académicas Herrerías y Casa de Cultura ambas en la alcaldía de Milpa Alta; los cuales están cursando el primero, tercero y quinto semestre de la licenciatura en Contabilidad y Finanzas (LCFI) su inclusión tiene la finalidad de generar en los estudiantes un aprendizaje basado en proyectos significativos y este estudio de caso contribuyó a ello.
Control de Sclerotinia Sclerotiorum Mediante Tratamiento Químico, Biológico y con Organismo Macrobiótico en el Cultivo de Alcachofa Cynara Scolymus L
Authors: Torres Donayre Stella Maris , Mattos Calderón Luz Leonor 
Published: April 2024

En el presente trabajo se evaluó el efecto de tres tratamientos: químico, biológico y organismo macrobiótico para el control de Sclerotinia sclerotiorum en alcachofa (Cynara Scolymus L.). Se realizó un ensayo bajo condiciones de invernadero y laboratorio en la Universidad Nacional Agraria La Molina. El análisis estadístico utilizado para el control químico, biológico y macrobiótico de Sclerotinia en el suelo fue la prueba de Kruskall Wallis con 4 repeticiones por tratamiento, y se realizó la prueba de Chi cuadrado para comparación de medias (p= 0.05).El análisis estadístico utilizado para el control químico, biológico y macrobiótico a nivel de plántula de alcachofa fue el Diseño Completamente Aleatorizado (DCA) con 5 repeticiones por tratamiento y se realizó la prueba de comparación de medias de Duncan (p=0,05) para todas las variables biométricas evaluadas en el invernadero.En la fase de control de esclerotes en el suelo, el control químico mediante Boscalid inhibió el 100% de la germinación de esclerotes a 750 gr/ha. y 1000gr/ha; en el control biológico, Trichoderma harzianum a dosis de 600gr/ha presentó un 21% de esclerotes germinados; en el control macrobiótico, con 50 lombrices de tierra, se obtuvo un 44% de esclerotes germinados. En la fase de control a nivel de plántula, en el control químico Boscalid a la dosis de 750gr/ha, y 1000gr/ha hubo 0,0% de plantas infectadas; para el control biológico, Trichoderma harzianum a 700gr/ha se obtuvo 0,0% de plantas infectadas y en el caso del control macrobiótico con 50 lombrices de tierra hubo 20% de plantas infectadas. El tratamiento testigo presentó un 100% de plantas infectadas. Las variables biométricas evaluadas en los tratamientos químico, biológico y macrobiótico superaron el promedio alcanzado por el testigo.
Menteşâ Emîrliği’nin İbtidâsı ve Menteşâ İmlası
Authors: Keçiş Murat , Baykara Refik 
Published: April 2024

Türkiye Selçuklu Devleti’nin siyasi bütünlüğünün parçalanmasına sebep olan Moğol İstilası, Anadolu’nun Türkleşme sürecinin son safhası kabul edilen II. Beylikler Dönemi’nin başlamasına yol açmıştır. Bu devrin başlaması aynı zamanda, Türkiye Selçuklu Devleti’nin yıkılma sürecine girmesine ve Türkmen beylerinin, Selçuklu otoritesinin kaybolduğu bölgeler ile merkezi otoritesi zayıflayan Bizans’ın doğu sınırlarında, müstakil ya da yarı müstakil hâlde devletçikler şeklinde teşkilatlanmalarıyla devam etmiştir.
Batı Anadolu’da söz konusu dönemde kurulan siyasi teşekküllerden biri de Menteşâ Emîrliği’dir. İbtidâsı ve kurucusu olarak kabul edilen Menteşâ Bey hakkında 1934 yılından itibaren çeşitli görüşler mevcut olan emîrliğin, erken dönemleri hakkındaki vesikaların günümüze ulaşmaması ya da hiç telif edilmemesi sebebiyle, konuyla ilgili mevcut görüşler kesinlik arz etmemektedir. Bu durum, Menteşâ Emîrliği’nin kökeni hakkında çeşitli tartışmaları da beraberinde getirmekle kalmayıp, odak noktasından sapmalara neden olmakta ve sorunun çözümünü zorlaştırmaktadır. Konuyla ilgili olarak 90 yıllık süreçte yapılan çalışmalarda Menteşâ imlası bir şahıs ismi olarak değerlendirilerek problemin çözüm yollarının arandığı malumdur.
Bu çalışmada dönem kaynaklarından ve araştırma eserlerden istifade edilerek, emîrliğin zuhuru ve “منتشا “imlasının transkripsiyonunun tespiti ile mevcut önermelerin dâhilinde konu farklı bir perspektiften tekrar değerlendirilmiş, yeni yaklaşımlar elde edilmiştir. Böylelikle sonucun ve sorunsalın karmaşası büyük ölçüde ortadan kalkmış ve emîrliğin ibtidâsı ile ilgili daha sarih verilere ulaşılmıştır.
Multiband Spectropolarimetry of Lunar Maria, Pyroclastics, Fresh Craters, and Swirl Materials
Authors: Wöhler Christian , Arnaut Mirza , Bhatt Megha 
Published: April 2024

Abstract
Imaging polarimetry is a well-known method for examining the small-scale structure of the surface regolith of airless celestial bodies. In this study, we examine (for the first time) the wavelength-dependent polarization behavior of selected lunar areas, including maria, highlands, fresh craters, pyroclastic deposits, and the Reiner Gamma swirl, based on telescopic multiband UBVRI imaging polarimetry at phase angles within the range of the positive polarization branch. The terrain-dependent spectropolarimetric behavior is studied for the first time in this work. For each study area, we conduct a mapping of the relative regolith grain size, an analysis of the exponent of the Umov law, and the wavelength dependence of the degree of linear polarization. Furthermore, we perform area-specific principal component analyses of the degree of linear polarization, followed by unsupervised machine learning (clustering) to segment different terrain types. We find that fresh mare craters and high-titanium pyroclastic deposits have an increased regolith grain size, whereas crater ray material, low-titanium pyroclastic material, and the Reiner Gamma swirl are more finely grained than the average regolith. The degree of linear polarization decreases with increasing wavelength-dependent albedo according to a power law whose exponent is itself positively correlated with the albedo. For a constant albedo and grain size, the degree of linear polarization increases linearly with wavelength. The clustering step yields a library of terrain-dependent prototype spectra of the degree and angle of linear polarization.
Stellar Metallicities and Gradients in the Isolated, Quenched Low-mass Galaxy Tucana
Authors: Fu Sal Wanying , Weisz Daniel R. , Starkenburg Else , Martin Nicolas , Mercado Francisco J. , Savino Alessandro , Boylan-Kolchin Michael , Côté Patrick , Dolphin Andrew E. , Longeard Nicolas , Mateo Mario L. , Samuel Jenna , Sandford Nathan R. 
Published: April 2024

Abstract
We measure the metallicities of 374 red giant branch (RGB) stars in the isolated, quenched dwarf galaxy Tucana using Hubble Space Telescope narrowband (F395N) calcium H and K imaging. Our sample is a factor of ∼7 larger than what is available from previous studies. Our main findings are as follows. (i) A global metallicity distribution function (MDF) with

〈
[Fe/H]
〉
=
−

1.55

−
0.04

+
0.04

and

σ

[Fe/H]

=

0.54

−
0.03

+
0.03

. (ii) A metallicity gradient of −0.54 ± 0.07 dex

R

e

−
1

(−2.1 ± 0.3 dex kpc−1) over the extent of our imaging (∼2.5 R

e
), which is steeper than literature measurements. Our finding is consistent with predicted gradients from the publicly available FIRE-2 simulations, in which bursty star formation creates stellar population gradients and dark matter cores. (iii) Tucana’s bifurcated RGB has distinct metallicities: a blue RGB with

〈
[Fe/H]
〉
=
−

1.78

−
0.06

+
0.06

and

σ

[Fe/H]

=

0.44

−
0.06

+
0.07

and a red RGB with

〈
[Fe/H]
〉
=
−

1.08

−
0.07

+
0.07

and

σ

[Fe/H]

=

0.42

−
0.06

+
0.06

. (iv) At fixed stellar mass, Tucana is more metal-rich than Milky Way satellites by ∼0.4 dex, but its blue RGB is chemically comparable to the satellites. Tucana’s MDF appears consistent with star-forming isolated dwarfs, though MDFs of the latter are not as well populated. (v) About 2% of Tucana’s stars have [Fe/H] < −3% and 20% have [Fe/H] > −1. We provide a catalog for community spectroscopic follow-up.
Magnetized Fingering Convection in Stars
Authors: Fraser Adrian E. , Reifenstein Sam A. , Garaud Pascale 
Published: April 2024

Abstract
Fingering convection (also known as thermohaline convection) is a process that drives the vertical transport of chemical elements in regions of stellar radiative zones where the mean molecular weight increases with radius. Recently, Harrington & Garaud used three-dimensional direct numerical simulations (DNS) to show that a vertical magnetic field can dramatically enhance the rate of chemical mixing by fingering convection. Furthermore, they proposed a so-called “parasitic saturation” theory to model this process. Here, we test their model over a broad range of parameter space, using a suite of DNS of magnetized fingering convection, varying the magnetic Prandtl number, magnetic field strength, and composition gradient. We find that the rate of chemical mixing measured in the simulations is not always predicted accurately by their existing model, in particular when the magnetic diffusivity is large. We then present an extension of the Harrington & Garaud model which resolves this issue. When applied to stellar parameters, it recovers the results of Harrington & Garaud except in the limit where fingering convection becomes marginally stable, where the new model is preferred. We discuss the implications of our findings for stellar structure and evolution.
Reliable Identification of Binary Supermassive Black Holes from Rubin Observatory Time-domain Monitoring
Authors: Davis Megan C. , Grace Kaylee E. , Trump Jonathan R. , Runnoe Jessie C. , Henkel Amelia , Blecha Laura , Brandt W. N. , Casey-Clyde J. Andrew , Charisi Maria , Witt Caitlin A. 
Published: April 2024

Abstract
Periodic signatures in time-domain observations of quasars have been used to search for binary supermassive black holes (SMBHs). These searches, across existing time-domain surveys, have produced several hundred candidates. The general stochastic variability of quasars, however, can masquerade as a false-positive periodic signal, especially when monitoring cadence and duration are limited. In this work, we predict the detectability of binary SMBHs in the upcoming Rubin Observatory Legacy Survey of Space and Time (LSST). We apply computationally inexpensive sinusoidal curve fits to millions of simulated LSST Deep Drilling Field light curves of both single, isolated quasars and binary quasars. The period and phase of simulated binary signals can generally be disentangled from quasar variability. Binary amplitude is overestimated and poorly recovered for two-thirds of potential binaries due to quasar accretion variability. Quasars with strong intrinsic variability can obscure a binary signal too much for recovery. We also find that the most luminous quasars mimic current binary candidate light curves and their properties: The false-positive rates are 60% for these quasars. The reliable recovery of binary period and phase for a wide range of input binary LSST light curves is promising for multi-messenger characterization of binary SMBHs. However, pure electromagnetic detections of binaries using photometric periodicity with amplitude greater than 0.1 mag will result in samples that are overwhelmed by false positives. This paper represents an important and computationally inexpensive way forward for understanding the true and false-positive rates for binary candidates identified by Rubin.
Reconstruction of Cosmological Initial Density Field with Observations from the Epoch of Reionization
Authors: Zhou Meng , Mao Yi 
Published: April 2024

Abstract
The initial density distribution provides a basis for understanding the complete evolution of cosmological density fluctuations. While reconstruction in our local Universe exploits the observations of galaxy surveys with large volumes, observations of high-redshift galaxies are performed with a small field of view and therefore can hardly be used for reconstruction. Here, we propose reconstructing the initial density field using the H i 21 cm and CO line intensity maps from the epoch of reionization. Observations of these two intensity maps provide complementary information on the density field—the H i 21 cm field is a proxy of matter distributions in the neutral regions, while the CO line intensity maps are sensitive to the high-density, star-forming regions that host the sources for reionization. Technically, we employ the conjugate gradient method and develop the machinery for minimizing the cost function for the intensity mapping observations. Analytical expressions for the gradient of cost function are derived explicitly. We show that the resimulated intensity maps match the input maps of mock observations using semi-numerical simulations of reionization with an rms error ≲7% at all stages of reionization. This reconstruction is also robust with an rms error of ∼10% when an optimistic level of shot noise is applied to the CO map or white noise at the level of ≲10% of the standard deviation is applied to each map. Our proof-of-concept work demonstrates the robustness of the reconstruction method, thereby providing an effective technique for reconstructing the cosmological initial density distribution from high-redshift observations.
Relativistic Alfvén Turbulence at Kinetic Scales
Authors: Vega Cristian , Boldyrev Stanislav , Roytershteyn Vadim 
Published: April 2024

Abstract
In a strongly magnetized, magnetically dominated relativistic plasma, Alfvénic turbulence can extend to scales much smaller than the particle inertial scales. It leads to an energy cascade somewhat analogous to inertial- or kinetic-Alfvén turbulent cascades existing in nonrelativistic space and astrophysical plasmas. Based on phenomenological modeling and particle-in-cell numerical simulations, we propose that the energy spectrum of such relativistic kinetic-scale Alfvénic turbulence is close to k
−3 or slightly steeper than that due to intermittency corrections or Landau damping. We note the analogy of this spectrum with the Kraichnan spectrum corresponding to the enstrophy cascade in 2D incompressible fluid turbulence. Such turbulence strongly energizes particles in the direction parallel to the background magnetic field, leading to nearly one-dimensional particle momentum distributions. We find that these distributions have universal log-normal statistics.
Search for GeV Gamma-Ray Emission from Possible TeV-bright Red Dwarfs with Fermi-LAT
Authors: Huang Chen , Zhang Xiao , Chen Yang , Zhong Wenjuan 
Published: April 2024

Abstract
Red dwarfs have been suggested to be among the possible astrophysical species accelerating particles and emitting TeV γ-rays. In an effort to search for the GeV γ-ray counterparts of the suggested TeV emission from eight red dwarfs, we analyze the 0.2–500 GeV γ-ray emission of the regions covering them, exploiting the ∼13.6 yr Pass 8 data from the Fermi Large Area Telescope (LAT). A GeV γ-ray emission excess with a significance of 3.8σ is detected in the direction of the red dwarf V962 Tau. This emission contains V962 Tau in a 1σ error radius and is independent of the catalog source. However, the stellar flare scenario can hardly explain the total energy and lightcurve (LC) derived from the γ-ray emission in view of the spectral analysis. We also analyze the LCs in the positions of the eight red dwarfs, and no time bin with a significance >5σ is found. Therefore, no significant emission from the red dwarfs could be concluded to have been detected by Fermi-LAT.
Case Report: Profound Anemia in a 2-Year-Old Boy Associated with a Leech in the Oropharynx
Authors: Koleski Jerome , Kipngetich Kurgat Amos , Tindal Emilie , Haugen Jenna 
Published: April 2024

ABSTRACT.
A 2-year-old boy presented to Kapsowar Mission Hospital in Kenya with a history of general tiredness associated with mild, unilateral epistaxis and one episode of hematemesis. On admission, he had a hemoglobin value of 3.5 g/dL, with a white cell count of 20.6 × 109/L. The child was examined by the physician on call, with no source of bleeding found. Later that day, after a local physician noted that the presentation could be due to an unrecognized leech infestation, a deep examination of the oropharynx was performed with a laryngoscope and revealed a leech attached deep in the oropharynx. The anesthetist visualized the leech with a laryngoscope and removed it with Magill forceps. After the procedure and blood transfusion, the child’s hemoglobin level improved to 10.4 g/dL, and on the following day, the child was much improved in energy and was playing outside. He was discharged home on iron supplements and made a full recovery.
The Nearly Impossible Conquest of the Guatemalan Lowlands
Authors: Ovando Cesar 
Published: April 2024

During the sixteenth and seventeenth centuries, most of Mesoamerica was invaded and colonized by the Spanish conquistadors. We are to believe from their accounts that their triumph over several indigenous communities was inevitable. However, that wasn’t the case as various native groups resisted the Spanish presence during the conquest, which ultimately delayed their colonization. One group that gave the Spaniards trouble during the invasion was the Maya. Although there were several lineages throughout southern Mexico and Central America, it was the Maya in Central Petén that ultimately delayed Spanish colonization in Mesoamerica.
So, what happened during the conquest of Central Petén? What made this campaign different from others? Why were the Maya in Central Petén more challenging to conquer than other indigenous communities in Mesoamerica? All these questions are answered in this research paper, which documents Maya's advantages during the conquest. Using various sources, primary and secondary, I have shared the research and theoretical perspectives of archeologists, who have unearthed the Mayas' sociocultural continuities they used against the Spaniards, which promotes indigenous agency. In this paper, I ultimately argue that the Spanish were unprepared to handle the Guatemalan lowlands' landscape (which is where Central Petén is located). With a lack of knowledge of the lowlands' geography, the Maya countered the Spanish presence until the seventeenth century.
Late Preclassic to Early Classic Maya Transition and Patterns
Authors: Molina Astrid 
Published: April 2024

The Late Preclassic period in the Maya Lowlands experienced major changes that led to the transition of the Early Classic Maya. The anthropogenic changes and climate change that developed and progressed in the Late Preclassic era, led the people of this period to develop new technology, traditions, trade and migration to overcome their unexpected challenges. The deforestation of the lowlands caused changes to the lands that affected their source of vegetation and water management. They were also experiencing lack of rain which was unusual for their environment. They had to develop new technology in order to collect water for their crops, animals, and themselves. Larger sites had a difficult time trying to keep up with the changes and taking care of their large sized population. This gave an advantage to the smaller sites and many overcame these struggles and later developed into larger sites in the Classic Period. The shift in site strength and growth led to new trade systems that continued into the Early Classic Period. The migration of the people also opened up new doors to trade, but also traditions. They brought their customs into their new homes and these customs changes and transitioned into new traditions in the Classic Period.
Holism in Development
Authors: Fuqua Peter 
Published: April 2024

This study sought to understand the purposes and effects of development projects carried out in marginalized places. To get a foundation on how these projects work, I researched the Thaba-Tseka project, which was active in the late 1970s through the early 1980s. The central ethnography I used for this research was The Anti-Politics Machine: “Development,” Depoliticization, and Bureaucratic Power in Lesotho by James Ferguson (1990). Additionally, I investigated how traditional ecological knowledge and a holistic approach can realign development values to be less ethnocentric. This study shows that while development projects tend to be bad for the groups that they intend to assist, there is potential for improvement through a reversal of approach. There is potential for development projects to bring about positive change in the world through the incorporation of holistic perspectives and traditional ecological knowledge.