bluuebunny/crossref_metadata_2025_split huggingface dataset:
Manejo anestésico de pacientes con covid-19: prevención y control quirúrgico
Authors: Moreira Véliz Lisseth Alejandra , Sánchez Fernández Juan Pablo , Salas Hurtado Ingrid Lissette 
Published: February 2021

La infección por covid-19, un nuevo tipo de coronavirus, cuyo epicentro de esta pandemia inició en Wuhan, China en diciembre del 2019 provoco una diseminación global, con una alta posibilidad de infectarse en cualquier parte del mundo, especialmente en áreas urbanas densas. En el campo de la anestesiología supone un alto riesgo de contagio, debido al acercamiento a las vías respiratorias del paciente, exponiendo al personal de salud a las secreciones respiratorias en aerosol. Se seleccionó toda la literatura relevante sobre covid-19 y anestesia, con un enfoque en el manejo, prevención y control durante la cirugía. De un total de 44 artículos seleccionados de junio a diciembre del 2020, se excluyeron los estudios sobre tratamiento, ensayos clínicos y metaanálisis, quedando para el análisis 15 artículos. La finalidad de esta revisión es proporcionar una actualización de la enfermedad para ampliar los conocimientos y mejor la calidad de atención.
MagAO Observations of the Binary Microlens OGLE-2014-BLG-1050 Prefer the Higher-mass Solution*
Authors: Xie Xiaojia , Dong Subo , Zhu Wei , Gould A. , Udalski A. , Beaulieu J.-P. , Close L. M. , Males J. R. , Marquette J.-B. , Morzinski K. M. , Pogge R. W. , Yee J. C. 
Published: February 2021

Abstract
We report adaptive optics (AO) follow-up imaging of OGLE-2014-BLG-1050, which is the second binary microlensing event with space-based parallax measurements. The degeneracy in microlens parallax π
E led to two sets of solutions, either a ∼ (0.9, 0.35)M
⊙ binary at ∼3.5 kpc or a ∼(0.2, 0.07)M
⊙ binary at ∼1.1 kpc. We measure the flux blended with the microlensed source by conducting Magellan AO observations, and find that the blending is consistent with the predicted lens flux from the higher-mass solution. From the combination of the AO flux measurement together with previous lensing constraints, it is estimated that the lens system consists of a

primary and a

secondary at

kpc.
Host Star Metallicity of Directly Imaged Wide-orbit Planets: Implications for Planet Formation
Authors: Swastik C. , Banyal Ravinder K. , Narang Mayank , Manoj P. , Sivarani T. , Reddy Bacham E. , Rajaguru S. P. 
Published: February 2021

Abstract
Directly imaged planets (DIPs) are self-luminous companions of pre-main-sequence and young main-sequence stars. They reside in wider orbits (∼tens to thousands of astronomical units) and generally are more massive compared to the close-in (≲10 au) planets. Determining the host star properties of these outstretched planetary systems is important to understand and discern various planet formation and evolution scenarios. We present the stellar parameters and metallicity ([Fe/H]) for a subsample of 18 stars known to host planets discovered by the direct imaging technique. We retrieved the high-resolution spectra for these stars from public archives and used the synthetic spectral fitting technique and Bayesian analysis to determine the stellar properties in a uniform and consistent way. For eight sources, the metallicities are reported for the first time, while the results are consistent with the previous estimates for the other sources. Our analysis shows that metallicities of stars hosting DIPs are close to solar with a mean [Fe/H] = −0.04 ± 0.27 dex. The large scatter in metallicity suggests that a metal-rich environment may not be necessary to form massive planets at large orbital distances. We also find that the planet mass–host star metallicity relation for the directly imaged massive planets in wide orbits is very similar to that found for the well-studied population of short-period (≲1 yr) super-Jupiters and brown dwarfs around main-sequence stars.
s-processing in AGB Stars Revisited. III. Neutron Captures from MHD Mixing at Different Metallicities and Observational Constraints
Authors: Busso Maurizio , Vescovi Diego , Palmerini Sara , Cristallo Sergio , Antonuccio-Delogu Vincenzo 
Published: February 2021

Abstract
We present post-process neutron-capture computations for Asymptotic Giant Branch (AGB) stars of 1.5–3 M
⊙ and metallicities −1.3 ≤ [Fe/H] ≤ 0.1. The reference stellar models are computed with the FRANEC code, using the Schwarzschild's criterion for convection; our motivations for this choice are outlined. We assume that MHD processes induce the penetration of protons below the convective boundary, when the Third Dredge Up occurs. There, the 13C n-source can subsequently operate, merging its effects with those of the 22Ne(α, n)25Mg reaction, activated at the temperature peaks characterizing AGB stages. This work has three main scopes. (i) We provide a grid of abundance yields, as produced through our MHD mixing scheme, which are uniformly sampled in mass and metallicity. From this, we deduce that the solar s-process distribution, as well as the abundances in recent stellar populations, can be accounted for, without the need of the extra primary-like contributions suggested in the past. (ii) We formulate analytic expressions for the mass of the 13C-pockets generated to allow easy verification of our findings. (iii) We compare our results with observations of evolved stars and with isotopic ratios in presolar SiC grains, also noticing how some flux tubes should survive turbulent disruption, carrying C-rich materials into the winds even when the envelope is O-rich. This wind phase is approximated through the G-component of AGB s-processing. We conclude that MHD-induced mixing is adequate to drive slow n-capture phenomena accounting for observations; our prescriptions should permit its inclusion into current stellar evolutionary codes.
Revealing the Accretion Physics of Supermassive Black Holes at Redshift z ∼ 7 with Chandra and Infrared Observations
Authors: Wang Feige , Fan Xiaohui , Yang Jinyi , Mazzucchelli Chiara , Wu Xue-Bing , Li Jiang-Tao , Bañados Eduardo , Farina Emanuele Paolo , Nanni Riccardo , Ai Yanli , Bian Fuyan , Davies Frederick B. , Decarli Roberto , Hennawi Joseph F. , Schindler Jan-Torge , Venemans Bram , Walter Fabian 
Published: February 2021

Abstract
X-ray emission from quasars has been detected up to redshift z = 7.5, although only limited to a few objects at z > 6.5. In this work, we present new Chandra observations of five z > 6.5 quasars. By combining with archival Chandra observations of six additional z > 6.5 quasars, we perform a systematic analysis on the X-ray properties of these earliest accreting supermassive black holes (SMBHs). We measure the black hole masses, bolometric luminosities (L
bol), Eddington ratios (λ
Edd), emission line properties, and infrared luminosities (L
IR) of these quasars using infrared and submillimeter observations. Correlation analysis indicates that the X-ray bolometric correction (the factor that converts from X-ray luminosity to bolometric luminosity) decreases with increasing L
bol, and that the UV/optical-to-X-ray ratio, α
ox, strongly correlates with L
2500 Å
, and moderately correlates with λ
Edd and blueshift of C iv emission lines. These correlations are consistent with those found in lower-z quasars, indicating quasar accretion physics does not evolve with redshift. We also find that L
IR does not correlate with L
2–10 keV in these luminous distant quasars, suggesting that the ratio of the SMBH growth rate and their host galaxy growth rate in these early luminous quasars are different from those of local galaxies. A joint spectral analysis of the X-ray detected z > 6.5 quasars yields an average X-ray photon index of

, steeper than that of low-z quasars. By comparing it with the Γ − λ
Edd relation, we conclude that the steepening of Γ for quasars at z > 6.5 is mainly driven by their higher Eddington ratios.
PSR J1709-4429's Proper Motion and Its Relationship to SNR G343.1–2.3
Authors: de Vries Martijn , Romani Roger W. , Kargaltsev Oleg , Pavlov George , Posselt Bettina , Slane Patrick , Bucciantini Niccolo’ , Ng C.-Y. , Klingler Noel 
Published: February 2021

Abstract
We have obtained a deep (670 ks) CXO ACIS image of the remarkable pulsar wind nebula (PWN) of PSR J1709−4429, in four epochs during 2018–2019. Comparison with an archival 2004 data set provides a pulsar proper motion μ = 13 ± 3 mas yr−1 at a PA of 86° ± 9° (1σ combined statistical and systematic uncertainties), precluding birth near the center of SNR G343.1−2.3. At the pulsar’s characteristic age of 17 kyr, the association can be preserved through a combination of progenitor wind, birth kick, and PWN outflow. Associated TeV emission may, however, indicate an explosion in an earlier supernova. Inter-epoch comparison of the X-ray images shows that the PWN is dynamic, but we are unable to conclusively measure flow speeds from blob motion. The pulsar has generated a radio/X-ray wind bubble, and we argue that the PWN’s long narrow jets are swept back by shocked pulsar wind venting from this cavity. These jets may trace the polar magnetic field lines of the PWN flow, an interesting challenge for numerical modeling.
An Improved Hertzsprung–Russell Diagram for the Orion Trapezium Cluster
Authors: Fang Min , Kim Jinyoung Serena , Pascucci Ilaria , Apai Dániel 
Published: February 2021

Abstract
We present a study of the Trapezium cluster in Orion. We analyze flux-calibrated Very Large Telescope/Multi-Unit Spectroscopic Explorer spectra of 361 stars to simultaneously measure the spectral types, reddening, and the optical veiling due to accretion. We find that the extinction law from Cardelli et al. with a total-to-selective extinction value of R
V = 5.5 is more suitable for this cluster. For 68% of the sample the new spectral types are consistent with literature spectral types within two subclasses but, as expected, we derive systematically later types than the literature by one to two subclasses for the sources with significant accretion levels. Here we present an improved Hertzsprung–Russell (H-R) diagram of the Trapezium cluster, in which the contamination by optical veiling on spectral types and stellar luminosities has been properly removed. A comparison of the locations of the stars in the H-R diagram with the non-magnetic and magnetic pre-main-sequence evolutionary tracks indicates an age of 1–2 Myr. The magnetic pre-main-sequence evolutionary tracks can better explain the luminosities of the low-mass stars. In the H-R diagram, the cluster exhibits a large luminosity spread (σ(Log L
⋆/L
⊙) ∼ 0.3). By collecting a sample of 14 clusters/groups with different ages, we find that the luminosity spread tends to be constant (σ(Log L
⋆/L
⊙) ∼ 0.2–0.25) after 2 Myr, which suggests that age spread is not the main cause of the luminosity spread. There are ∼0.1 dex larger luminosity spreads for the younger clusters, e.g., the Trapezium cluster, than the older clusters, which can be explained by the starspots, accretion history, and circumstellar disk orientations.
The Formation of Carbonaceous Material in the Early Solar Nebula: The Role of Metal Dusting
Authors: Ferguson Frank T. , Johnson Natasha M. , Abreu Neyda , Nuth Joseph A. 
Published: February 2021

Abstract
For many years it has been suggested that the carbonaceous material found in association with Fe/Ni metal and metal carbides in primitive bodies is linked to the Fischer–Tropsch reaction. This is especially true with chondritic-porous interplanetary dust particles, which are considered to have a cometary origin and are among some of the most primitive and least processed materials available for study. Another phenomenon which occurs under the same carburizing conditions as the Fischer–Tropsch reaction is called metal dusting and could be a possible pathway to forming some of the carbonaceous material found in primitive bodies. Metal dusting is a catastrophic corrosion of metal under these carburizing conditions that results in a porous mixture of carbonaceous material, metal, and metal carbides. In the case of pure iron, type I metal dusting results in the formation of a metastable iron carbide, typically cementite, Fe3C. While metal dusting has been studied industrially for over 50 years, it does not appear to have been applied to the formation of carbonaceous material in astrophysical settings. In this work, the general mechanism of metal dusting on iron is described and a thermodynamic analysis of the dusting phenomena applied to solar nebula conditions. Rate measurements are made with pure iron samples over the temperature range from 400°C to 950°C. In addition, the products from experimental runs at 500°C and 600°C are studied by transmission electron microscopy. Results show that iron carbide particles are formed with carbonaceous material consisting of poorly graphitized carbon.
Universal Conditional Distribution Function of [O ii] Luminosity of Galaxies, and Prediction for the [O ii] Luminosity Function at Redshift z < 3
Authors: Gao Hongyu , Jing Y. P. 
Published: February 2021

Abstract
The star-forming emission line galaxies (ELGs) with a strong [O ii] doublet are one of the main spectroscopic targets for the ongoing and upcoming fourth-generation galaxy redshift surveys. In this work, we measure the [O ii] luminosity L
[O II] and the absolute magnitude in the near-ultraviolet (NUV) band M
NUV for a large sample of galaxies in the redshift range 0.6 ≤ z < 1.45 from the Public Data Release 2 (PDR-2) of the VIMOS Public Extragalactic Redshift Survey (VIPERS). We aim to construct the intrinsic relationship between L
[O II] and M
NUV through Bayesian analysis. In particular, we develop two different methods to properly correct for the incompleteness effect and observational errors in the [O ii] emission line measurement. Our results indicate that the conditional distribution of L
[O II] at a given M
NUV can be well described by a universal probability distribution function (PDF), which is independent of M
NUV and redshift. Convolving the L
[O II] conditional PDF with the NUV luminosity function (LF) available in the literature, we make a prediction for [O ii] LFs at z < 3. The predicted [O ii] LFs are in good agreement with the observational results from the literature. Finally, we utilize the predicted [O ii] LFs to estimate the number counts of [O ii] emitters for the Subaru Prime Focus Spectrograph survey. This universal conditional PDF of L
[O II] provides a novel way to optimize the source targeting strategy for [O ii] emitters in future galaxy redshift surveys, and to model [O ii] emitters in theories of galaxy formation.
Observational Support for Massive Black Hole Formation Driven by Runaway Stellar Collisions in Galactic Nuclei
Authors: Escala Andrés 
Published: February 2021

Abstract
We explore a scenario for massive black hole formation driven by stellar collisions in galactic nuclei, proposing a new formation regime of global instability in nuclear stellar clusters triggered by runaway stellar collisions. Using order-of-magnitude estimations, we show that observed nuclear stellar clusters avoid the regime where stellar collisions are dynamically relevant over the whole system, while resolved detections of massive black holes are well into such collision-dominated regimes. We interpret this result in terms of massive black holes and nuclear stellar clusters being different evolutionary paths of a common formation mechanism, unified under the standard terminology of both being central massive objects. We propose a formation scenario where central massive objects more massive than ∼108
M
⊙, which also have relaxation times longer that their collision times, will be too dense (in virial equilibrium) to be globally stable against stellar collisions, and most of the mass will collapse toward the formation of a massive black hole. Contrarily, this will only be the case at the core of less dense central massive objects, leading to the formation of black holes with much lower black hole efficiencies

, with these efficiencies ϵ
BH drastically growing for central massive objects more massive than ∼107
M
⊙, approaching unity around M
CMO ∼ 108
M
⊙. We show that the proposed scenario successfully explains the relative trends observed in the masses, efficiencies, and scaling relations between massive black holes and nuclear stellar clusters.
Mitomycin C Application After Corneal Cross-linking for Keratoconus Increases Stromal Haze
Authors: Awwad Shady T. , Chacra Lily M. , Helwe Chadi , Dhaini Ahmad R. , Telvizian Talar , Torbey Julien , Abdul Fattah Maamoun , Torres-Netto Emilio A. , Hafezi Farhad , Shetty Rohit 
Published: February 2021

PURPOSE:
To evaluate and compare corneal haze as determined by optical coherence tomography (OCT) after corneal cross-linking (CXL) for the treatment of mild to moderate keratoconus with or without mitomycin C (MMC) application.

METHODS:
This was a retrospective analysis of 87 eyes of 72 patients with mild to moderate keratoconus. The first group (n = 44 eyes) underwent CXL between June 2013 and January 2015 and the second group (n = 43 eyes) underwent CXL with MMC (CXL+MMC) between February and December 2015, both following the Dresden protocol. Patients were evaluated preoperatively and at 1, 3, 6, and 12 months postoperatively. Main outcome measures were corneal reflectivity and haze reflectivity measured by a specially developed OCT image analysis software.

RESULTS:

Anterior corneal reflectivity at 1 month and 1 year postoperatively was 14.79 ± 4.68 and 25.97 ± 15.01 (
P
< .001), and 13.88 ± 4.39 and 18.41 ± 9.25 (
P
= .025) for the CXL and CXL+MMC groups, respectively. The reflectivity of the anterior stromal haze region at 1 month and 1 year postoperatively was 23.15 ± 5.91 and 33.14 ± 16.58 (
P
= .005), and 20.58 ± 7.88 and 27.14 ± 12.80 (
P
= .049) for both groups, respectively. The changes in simulated keratometry from preoperatively to postoperatively were similar in both groups. The CXL+MMC group showed larger maximum keratometry flattening: 53.41 ± 6.88 diopters (D) preoperatively and 49.44 ± 5.66 D 1 year postoperatively versus 52.27 ± 5.78 and 50.91 ± 4.25 D for CXL alone (
P
= .008).

CONCLUSIONS:
MMC application following CXL significantly increases corneal haze. Similar studies need to be performed on simultaneous CXL and photorefractive keratectomy to evaluate the role of MMC in haze formation in such procedures.

[
J Refract Surg
. 2021;37(2):83–90.]
Phacoemulsification After Descemet Membrane Endothelial Keratoplasty: Incidence and Influence on Endothelial Cell Density
Authors: Vasiliauskaitė Indrė , Dhubhghaill Sorcha Ní , Ham Lisanne , Van Dijk Korine , Oellerich Silke , Melles Gerrit R. J. 
Published: February 2021

PURPOSE:
To analyze the incidence of cataract extraction after Descemet membrane endothelial keratoplasty (DMEK) in phakic eyes and to evaluate the effect of phacoemulsification after DMEK on the donor endothelial cell density (ECD).

METHODS:
The clinical data of phakic patients with DMEK were examined. From this cohort, all patients who subsequently underwent phacoemulsification after DMEK were reviewed. Data from a prospectively collected dataset were analyzed, including demographic profile, ECD, corrected distance visual acuity (CDVA), central corneal thickness (CCT), and complications.

RESULTS:

From a series of 261 phakic patients with DMEK, 35 eyes (13.4%) required cataract surgery within the mean follow-up period of 54.2 ± 28 months. The mean time from DMEK to phacoemulsification was 18 ± 13 months (range: 3 to 69 months). The probability of cataract extraction after DMEK was 0.06 (95% CI: 0.03 to 0.09) at 1 year and 0.17 (95% CI: 0.12 to 0.22) at 10 years, respectively. ECD decreased from 1,314 ± 524 cells/mm
2
before phacoemulsification to 1,167 ± 443 cells/mm
2
(−11%) at 1 to 6 months postoperatively (
P
= .333). CDVA improved from 0.27 ± 0.13 logMAR preoperatively to 0.07 ± 0.12 logMAR at 1 to 6 months postoperatively. CCT before phacoemulsification was 532 ± 46 µm and remained stable at 539 ± 56 µm at 1 to 6 months after phacoemulsification. Phacoemulsification did not elicit DMEK graft detachment in any of the eyes studied.

CONCLUSIONS:
The incidence and 10-year projection of cataract extraction in phakic eyes with DMEK was relatively low. Phacoemulsification after DMEK provided excellent CDVA outcomes, did not induce graft detachment, and was associated with an acceptable decrease in ECD.

[
J Refract Surg
. 2021;37(2):119–125.]
Designing a Tapperless Blade with an S-4320 Airfoil on a Micro-Scale Horizontal Axis Wind Turbine (Case Studies at PT Lentera Bumi Nusantara)
Authors: Simatupang Reza , Supriatna Deddy 
Published: February 2021

This article aims to design a taperless blade in a micro-scale wind turbine in medium wind speed, a case study at PT Lentera Bumi Nusantara. The methodology used in this research is quantitative research methods. Based on the test results in calculating the data using Microsoft Excel software and the blade airfoil design simulation using Qblade software, the use of the S-4320 airfoil in the application of the taperless blade design has research results that show that the airfoil design of the blade produces mechanical power at moderate wind speeds. It can be concluded that this blade design shows that the taperless blade with S-4320 airfoil can be applied to medium wind speeds in micro-scale horizontal axis wind turbines.
Artikel ini bertujuan untuk merancang bilah jenis taperless pada turbin angin skala mikro dalam kecepatan angin sedang, studi kasus pada PT Lentera Bumi Nusantara. Metodologi yang digunakan dalam penelitian ini adalah dengan metode penelitian kuantitatif. Berdasarkan hasil pengujian dalam perhitungan data menggunakan software Microsoft Excel dan simulasi perancangan desain airfoil bilah menggunakan software Qblade, penggunaan airfoil S-4320 dalam pengaplikasian desain bilah jenis taperless memiliki hasil penelitian yang menunjukan bahwa desain airfoil bilah tersebut menghasilkan tenaga mekanik pada kecepatan angin sedang. Dapat disimpulkan dalam desain bilah ini menunjukan bahwa bilah jenis taperless dengan airfoil S-4320 dapat diterapkan pada kecepatan angin sedang pada turbin angin sumbu horizontal skala mikro.
Improving Waste Bank Management Performance in Padang Pariaman
Authors: Humaira Humaira , Laura Fanny , Idmayanti Rika , Rasyidah Rasyidah , Rozi Fazrol 
Published: February 2021

The Nazhafa Garbage Bank is part of a Municipally owned corporation called BUMnag Pekandangan Emas, Padang Pariaman City. Cash data processing is still written in a book and MS Excel files. This resulted in the data not being recorded optimally. It takes long time to search for data, process transaction data and sometimes late payment of salaries to officers. Therefore, an information system for cash receipts and disbursements and remuneration was built at the Nazhafa Garbage Bank. This information system is built using codeigniter framework and MySQL DBMS. The final result is an information system that processes cash and salary data. With this system, you can record sales, record purchases, and record salaries every day or every month. This system can minimize the possibility of errors in data. This system improves the management performance of the Nazhafa Waste Bank.
Bank Sampah Nazhafa merupakan bagian dari badan usaha milik nagari atau disingkat dengan BUMnag Pakandangan Emas Kota Padang Pariaman. Pengolahan data kas masih ditulis dalam buku agenda, memerlukan waktu lama untuk mencari data, mengolah data transaksi pada data penerimaan dan pengeluaran kas, dan pemberian gaji ke pegawai. Sistem informasi penerimaan dan pengeluaran kas serta penggajian dibangun untuk mengelola data penerimaan kas dan pengeluaran kas serta penggajian pada Bank Sampah Nazhafa. Sistem ini menggunakan framework codeigniter dan DBMS MySQL. Hasil akhir didapati sebuah sistem informasi yang melakukan pengolahan data kas dan data gaji, mendata penjualan, mendata pembelian, dan mendata gaji setiap hari ataupun setiap bulannya. Sistem ini meningkatkan kinerja pengelolaan pada Bank Sampah Nazhafa.