bluuebunny/crossref_metadata_2025 huggingface dataset:
The complexity of definability by open first-order formulas
Authors: Areces Carlos , Campercholi Miguel , Penazzi Daniel , Ventura Pablo
Published: May 2020

In this article, we formally define and investigate the computational complexity of the definability problem for open first-order formulas (i.e. quantifier free first-order formulas) with equality. Given a logic $\boldsymbol{\mathcal{L}}$, the $\boldsymbol{\mathcal{L}}$-definability problem for finite structures takes as an input a finite structure $\boldsymbol{A}$ and a target relation $T$ over the domain of $\boldsymbol{A}$ and determines whether there is a formula of $\boldsymbol{\mathcal{L}}$ whose interpretation in $\boldsymbol{A}$ coincides with $T$. We show that the complexity of this problem for open first-order formulas (open definability, for short) is coNP-complete. We also investigate the parametric complexity of the problem and prove that if the size and the arity of the target relation $T$ are taken as parameters, then open definability is $\textrm{coW}[1]$-complete for every vocabulary $\tau $ with at least one, at least binary, relation.
Estimating COVID-19 outbreak risk through air travel
Authors: Daon Yair , Thompson Robin N , Obolski Uri
Published: June 2020

Background

Substantial limitations have been imposed on passenger air travel to reduce transmission of severe acute respiratory syndrome coronavirus 2 between regions and countries. However, as case numbers decrease, air travel will gradually resume. We considered a future scenario in which case numbers are low and air travel returns to normal. Under that scenario, there will be a risk of outbreaks in locations worldwide due to imported cases. We estimated the risk of different locations acting as sources of future coronavirus disease 2019 outbreaks elsewhere.

Methods

We use modelled global air travel data and population density estimates from locations worldwide to analyse the risk that 1364 airports are sources of future coronavirus disease 2019 outbreaks. We use a probabilistic, branching-process-based approach that considers the volume of air travelers between airports and the reproduction number at each location, accounting for local population density.

Results

Under the scenario we model, we identify airports in East Asia as having the highest risk of acting as sources of future outbreaks. Moreover, we investigate the locations most likely to cause outbreaks due to air travel in regions that are large and potentially vulnerable to outbreaks: India, Brazil and Africa. We find that outbreaks in India and Brazil are most likely to be seeded by individuals travelling from within those regions. We find that this is also true for less vulnerable regions, such as the United States, Europe and China. However, outbreaks in Africa due to imported cases are instead most likely to be initiated by passengers travelling from outside the continent.

Conclusions

Variation in flight volumes and destination population densities creates a non-uniform distribution of the risk that different airports pose of acting as the source of an outbreak. Accurate quantification of the spatial distribution of outbreak risk can therefore facilitate optimal allocation of resources for effective targeting of public health interventions.
Cannabinoid Hyperemesis Syndrome: An Unexpected Problem in an Unusual Setting—A Case Report
Authors: Stuart Rory , Richards John Ray
Published: May 2020

Cannabinoid hyperemesis syndrome presents with abdominal pain, nausea, and intractable vomiting caused by phytogenic and synthetic cannabinoid use. Complications associated with this disorder range from severe dehydration to acute kidney injury and rhabdomyolysis. This syndrome mimics many acute surgical and emergency medical conditions and can present several diagnostic and treatment challenges. While this syndrome is increasingly recognized as a common clinical entity in civilian emergency departments, there is little data concerning experience at military hospitals. We present a case of cannabinoid hyperemesis syndrome that was diagnosed and treated in a combat-zone US military emergency department in Southwest Asia.
Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models
Authors: Maraston C , Hill L , Thomas D , Yan R , Chen Y , Lian J , Parikh T , Neumann J , Meneses-Goytia S , Bershady M , Drory N , Bizyaev D , Concas A , Brownstein J , Lazarz D , Stringfellow G , Stassun K
Published: June 2020

We use the first release of the SDSS/MaStar stellar library comprising ∼9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the wavelength range 0.36–1.03 µm and share the same spectral resolution ($R\sim 1800$) and flux calibration as the SDSS-IV/MaNGA galaxy data. The parameter space covered by the stellar spectra collected thus far allows the calculation of models with ages and chemical composition in the range $\rm {\mathit{ t}\gt 200 \,Myr, -2 \lt = [Z/H] \lt = + 0.35}$, which will be extended as MaStar proceeds. Notably, the models include spectra for dwarf main-sequence stars close to the core H-burning limit, as well as spectra for cold, metal-rich giants. Both stellar types are crucial for modelling λ > 0.7 µm absorption spectra. Moreover, a better parameter coverage at low metallicity allows the calculation of models as young as 500 Myr and the full account of the blue horizontal branch phase of old populations. We present models adopting two independent sets of stellar parameters (Teff, log g, [Z/H]). In a novel approach, their reliability is tested ‘on the fly’ using the stellar population models themselves. We perform tests with Milky Way and Magellanic Clouds globular clusters, finding that the new models recover their ages and metallicities remarkably well, with systematics as low as a few per cent for homogeneous calibration sets. We also fit a MaNGA galaxy spectrum, finding residuals of the order of a few per cent comparable to the state-of-art models, but now over a wider wavelength range.
Lyman α absorption beyond the disc of simulated spiral galaxies
Authors: Röttgers Bernhard , Naab Thorsten , Cernetic Miha , Davé Romeel , Kauffmann Guinevere , Borthakur Sanchayeeta , Foidl Horst
Published: June 2020

We present an analysis of the origin and properties of the circumgalactic medium (CGM) in a suite of 11 cosmological zoom simulations resembling present-day spiral galaxies. On average the galaxies retain about 50 per cent of the cosmic fraction in baryons, almost equally divided into disc (interstellar medium) gas, cool CGM gas and warm-hot CGM gas. At radii smaller than 50 kpc the CGM is dominated by recycled warm-hot gas injected from the central galaxy, while at larger radii it is dominated by cool gas accreted on to the halo. The recycled gas typically accounts for one-third of the CGM mass. We introduce the novel publicly available analysis tool pygad to compute ion abundances and mock absorption spectra. For Lyman α absorption, we find good agreement of the simulated equivalent width (EW) distribution and observations out to large radii. Disc galaxies with quiescent assembly histories show significantly more absorption along the disc major axis. By comparing the EW and H i column densities, we find that CGM Lyman α absorbers are best represented by an effective line width b ≈ 50–70 km s−1 that increases mildly with halo mass, larger than typically assumed.
ATOMS: ALMA three-millimeter observations of massive star-forming regions – II. Compact objects in ACA observations and star formation scaling relations
Authors: Liu Tie , Evans Neal J , Kim Kee-Tae , Goldsmith Paul F , Liu Sheng-Yuan , Zhang Qizhou , Tatematsu Ken’ichi , Wang Ke , Juvela Mika , Bronfman Leonardo , Cunningham Maria R , Garay Guido , Hirota Tomoya , Lee Jeong-Eun , Kang Sung-Ju , Li Di , Li Pak-Shing , Mardones Diego , Qin Sheng-Li , Ristorcelli Isabelle , Tej Anandmayee , Toth L Viktor , Wu Jing-Wen , Wu Yue-Fang , Yi Hee-weon , Yun Hyeong-Sik , Liu Hong-Li , Peng Ya-Ping , Li Juan , Li Shang Huo , Lee Chang Won , Shen Zhi-Qiang , Baug Tapas , Wang Jun-Zhi , Zhang Yong , Issac Namitha , Zhu Feng-Yao , Luo Qiu-Yi , Liu Xun-Chuan , Xu Feng-Wei , Wang Yu , Zhang Chao , Ren Zhiyuan , Zhang Chao
Published: May 2020

We report studies of the relationships between the total bolometric luminosity (Lbol or LTIR) and the molecular line luminosities of J = 1 − 0 transitions of H13CN, H13CO+, HCN, and HCO+ with data obtained from ACA observations in the ‘ATOMS’ survey of 146 active Galactic star-forming regions. The correlations between Lbol and molecular line luminosities $L^{\prime }_{\rm mol}$ of the four transitions all appear to be approximately linear. Line emission of isotopologues shows as large scatters in Lbol–$L^{\prime }_{\rm mol}$ relations as their main line emission. The log(Lbol/$L^{\prime }_{\rm mol}$) for different molecular line tracers have similar distributions. The Lbol-to-$L^{\prime }_{\rm mol}$ ratios do not change with galactocentric distances (RGC) and clump masses (Mclump). The molecular line luminosity ratios (HCN-to-HCO+, H13CN-to-H13CO+, HCN-to-H13CN, and HCO+-to-H13CO+) all appear constant against Lbol, dust temperature (Td), Mclump, and RGC. Our studies suggest that both the main lines and isotopologue lines are good tracers of the total masses of dense gas in Galactic molecular clumps. The large optical depths of main lines do not affect the interpretation of the slopes in star formation relations. We find that the mean star formation efficiency (SFE) of massive Galactic clumps in the ‘ATOMS’ survey is reasonably consistent with other measures of the SFE for dense gas, even those using very different tracers or examining very different spatial scales.
Extended X-ray emission from the classic nova DQ Her – on the possible presence of a magnetized jet
Authors: Toalá J A , Guerrero M A , Santamaría E , Ramos-Larios G , Sabin L
Published: June 2020

We present an analysis of archival Chandra and XMM–Newton observations of the magnetically active cataclysmic variable DQ Her and the shell around it ejected in a nova event in 1934. A careful revision of the Chandra observations confirms previous claims on the presence of extended X-ray emission around DQ Her and reveals that it actually corresponds to a bipolar jet-like structure extending ≃32 arcsec along a direction from north-east to south-west. Therefore, this X-ray emission extends beyond the optical nova shell and is perpendicular to its major axis. The XMM–Newton observations confirm the presence of the extended X-ray emission detected by Chandra, suggesting the additional presence of a diffuse X-ray emission from a hot bubble filling the nova shell. This hot bubble was very likely produced by the explosion that created the nebular shell detected in optical images. The bipolar feature can be modelled by the combination of an optically thin plasma emission component with temperature T ≈ 2 × 106 K and a power-law component with a photon index of Γ = 1.1 ± 0.9. Its X-ray luminosity in the 0.3–5 keV energy range is LX = (2.1 ± 1.3) × 1029 erg s−1, for an electron density ne ≈ 2 cm−3 and a mass mX ≈ 3 × 10−6 M⊙. We suggest that the X-ray bipolar structure in DQ Her is a jet and interpret its non-thermal X-ray emission in terms of a magnetized jet.
The early growth of supermassive black holes in cosmological hydrodynamic simulations with constrained Gaussian realizations
Authors: Huang Kuan-Wei , Ni Yueying , Feng Yu , Di Matteo Tiziana
Published: May 2020

The paper examines the early growth of supermassive black holes (SMBHs) in cosmological hydrodynamic simulations with different BH seeding scenarios. Employing the constrained Gaussian realization, we reconstruct the initial conditions in the large-volume bluetides simulation and run them to z = 6 to cross-validate that the method reproduces the first quasars and their environments. Our constrained simulations in a volume of $(15 \, h^{-1} {\rm Mpc})^3$ successfully recover the evolution of large-scale structure and the stellar and BH masses in the vicinity of a ${\sim}10^{12} \, M_{\odot }$ halo which we identified in bluetides at z ∼ 7 hosting a ${\sim}10^9 \, M_{\odot }$ SMBH. Among our constrained simulations, only the ones with a low-tidal field and high-density peak in the initial conditions induce the fastest BH growth required to explain the z > 6 quasars. We run two sets of simulations with different BH seed masses of 5 × 103, 5 × 104, and $5 \times 10^5 \, h^{-1} M_{\odot }$, (i) with the same ratio of halo to BH seed mass and (ii) with the same halo threshold mass. At z = 6, all the SMBHs converge in mass to ${\sim}10^9 \, M_{\odot }$ except for the one with the smallest seed in (ii) undergoing critical BH growth and reaching 108 – $10^9 \, M_{\odot }$, albeit with most of the growth in (ii) delayed compared to set (i). The finding of eight BH mergers in the small-seed scenario (four with masses 104 – $10^6 \, M_{\odot }$ at z > 12), six in the intermediate-seed scenario, and zero in the large-seed scenario suggests that the vast BHs in the small-seed scenario merge frequently during the early phases of the growth of SMBHs. The increased BH merger rate for the low-mass BH seed and halo threshold scenario provides an exciting prospect for discriminating BH formation mechanisms with the advent of multimessenger astrophysics and next-generation gravitational wave facilities.
Topoisomerase II contributes to DNA secondary structure-mediated double-stranded breaks
Authors: Szlachta Karol , Manukyan Arkadi , Raimer Heather M , Singh Sandeep , Salamon Anita , Guo Wenying , Lobachev Kirill S , Wang Yuh-Hwa
Published: June 2020

DNA double-stranded breaks (DSBs) trigger human genome instability, therefore identifying what factors contribute to DSB induction is critical for our understanding of human disease etiology. Using an unbiased, genome-wide approach, we found that genomic regions with the ability to form highly stable DNA secondary structures are enriched for endogenous DSBs in human cells. Human genomic regions predicted to form non-B-form DNA induced gross chromosomal rearrangements in yeast and displayed high indel frequency in human genomes. The extent of instability in both analyses is in concordance with the structure forming ability of these regions. We also observed an enrichment of DNA secondary structure-prone sites overlapping transcription start sites (TSSs) and CCCTC-binding factor (CTCF) binding sites, and uncovered an increase in DSBs at highly stable DNA secondary structure regions, in response to etoposide, an inhibitor of topoisomerase II (TOP2) re-ligation activity. Importantly, we found that TOP2 deficiency in both yeast and human leads to a significant reduction in DSBs at structure-prone loci, and that sites of TOP2 cleavage have a greater ability to form highly stable DNA secondary structures. This study reveals a direct role for TOP2 in generating secondary structure-mediated DNA fragility, advancing our understanding of mechanisms underlying human genome instability.
Determinants of RNA recognition by the FinO domain of the Escherichia coli ProQ protein
Authors: Stein Ewa M , Kwiatkowska Joanna , Basczok Maciej M , Gravel Chandra M , Berry Katherine E , Olejniczak Mikołaj
Published: June 2020

The regulation of gene expression by small RNAs in Escherichia coli depends on RNA binding proteins Hfq and ProQ, which bind mostly distinct RNA pools. To understand how ProQ discriminates between RNA substrates, we compared its binding to six different RNA molecules. Full-length ProQ bound all six RNAs similarly, while the isolated N-terminal FinO domain (NTD) of ProQ specifically recognized RNAs with Rho-independent terminators. Analysis of malM 3′-UTR mutants showed that tight RNA binding by the ProQ NTD required a terminator hairpin of at least 2 bp preceding an 3′ oligoU tail of at least four uridine residues. Substitution of an A-rich sequence on the 5′ side of the terminator to uridines strengthened the binding of several ProQ-specific RNAs to the Hfq protein, but not to the ProQ NTD. Substitution of the motif in the malM-3′ and cspE-3′ RNAs also conferred the ability to bind Hfq in E. coli cells, as measured using a three-hybrid assay. In summary, these data suggest that the ProQ NTD specifically recognizes 3′ intrinsic terminators of RNA substrates, and that the discrimination between RNA ligands by E. coli ProQ and Hfq depends both on positive determinants for binding to ProQ and negative determinants against binding to Hfq.
Rapid, Noninvasive Diagnosis of Balamuthia mandrillaris Encephalitis by a Plasma-Based Next-Generation Sequencing Test
Authors: Kalyatanda Gautam , Rand Kenneth , Lindner Martin S , Hong David K , Sait Albayram Mehmet , Gregory Jason , Kresak Jesse , Ibne Karim M Ali , Cope Jennifer R , Roy Shantanu , Gary Joy M , Reddy Varalakshmi , Ahmed Asim A
Published: June 2020

Granulomatous amoebic encephalitis (GAE) caused by Balamuthia mandrillaris is a rare subacute infection with exceptionally high mortality. Diagnosis is typically made by brain biopsy or at autopsy. Detection of Balamuthia mandrillaris cell-free DNA by next-generation sequencing of plasma enabled rapid, noninvasive diagnosis in a case of amoebic encephalitis.
Proximity, NIMBYism, and Public Support for Energy Infrastructure
Authors: Konisky David M , Ansolabehere Stephen , Carley Sanya
Published: May 2020

The public opinion literature examining the role of proximity and not-in-my-backyard (NIMBY) attitudes in people’s judgments about energy projects has come to inconclusive findings. We argue that these mixed results are due to vast differences and significant limitations in research designs, which we mitigate through a large study (n = 16,200) of Americans’ attitudes toward energy projects. Our approach examines a diverse set of energy projects in development, explicitly compares the attitudes of individuals living in the vicinity of projects with those farther away, and includes the careful measurement of the NIMBY concept. The analyses show little evidence that proximity in general or NIMBY objections in particular are important determinants of project support. Instead, other factors are more important, including perceptions of local environmental quality, risk orientation, concern about climate change, and trust in energy companies.
Relational work in Nicaragua’s low-wage labor market
Authors: Ibañez Lindsey M
Published: May 2020

In low-wage labor markets, job seekers often rely on referrals from network members to find work. For job seekers, the challenge is to mobilize personal relationships to find work, and for contacts, the objective is to minimize risk while maintaining their relationships. Most of what we know about the low-wage job search comes from studies of societies with highly developed labor market institutions and social safety nets, leaving a gap in our understanding of less-institutionalized settings. This article analyzes the social processes through which job seekers and their contacts manage the risk and uncertainty of the low-wage labor market while managing their relationships with each other in Nicaragua, where steady employment is scarce and institutional supports are few. By applying the relational work framework, which is ideal for studying exchanges that occur among interpersonal relations in contexts of uncertainty, this study shows how job seekers and contacts pursue their goals of employment and risk management while maintaining their relations. Deceptive relational work is deployed by job seekers and contacts to preserve relationships when exchange is either impossible or undesirable, and the deceptive relational work of contacts disadvantages job seekers.
Modeling Mito-nuclear Compatibility and Its Role in Species Identification
Authors: Princepe Débora , De Aguiar Marcus A M
Published: May 2020

Mitochondrial genetic material (mtDNA) is widely used for phylogenetic reconstruction and as a barcode for species identification. The utility of mtDNA in these contexts derives from its particular molecular properties, including its high evolutionary rate, uniparental inheritance, and small size. But mtDNA may also play a fundamental role in speciation—as suggested by recent observations of coevolution with the nuclear DNA, along with the fact that respiration depends on coordination of genes from both sources. Here, we study how mito-nuclear interactions affect the accuracy of species identification by mtDNA, as well as the speciation process itself. We simulate the evolution of a population of individuals who carry a recombining nuclear genome and a mitochondrial genome inherited maternally. We compare a null model fitness landscape that lacks any mito-nuclear interaction against a scenario in which interactions influence fitness. Fitness is assigned to individuals according to their mito-nuclear compatibility, which drives the coevolution of the nuclear and mitochondrial genomes. Depending on the model parameters, the population breaks into distinct species and the model output then allows us to analyze the accuracy of mtDNA barcode for species identification. Remarkably, we find that species identification by mtDNA is equally accurate in the presence or absence of mito-nuclear coupling and that the success of the DNA barcode derives mainly from population geographical isolation during speciation. Nevertheless, selection imposed by mito-nuclear compatibility influences the diversification process and leaves signatures in the genetic content and spatial distribution of the populations, in three ways. First, speciation is delayed and the resulting phylogenetic trees are more balanced. Second, clades in the resulting phylogenetic tree correlate more strongly with the spatial distribution of species and clusters of more similar mtDNA’s. Third, there is a substantial increase in the intraspecies mtDNA similarity, decreasing the number of alleles substitutions per locus and promoting the conservation of genetic information. We compare the evolutionary patterns observed in our model to empirical data from copepods (Tigriopus californicus). We find good qualitative agreement in the geographic patterns and the topology of the phylogenetic tree, provided the model includes selection based on mito-nuclear interactions. These results highlight the role of mito-nuclear compatibility in the speciation process and its reconstruction from genetic data.[Mito-nuclear coevolution; mtDNA barcode; parapatry; phylogeny.]
Effect of summer warming on growth, photosynthesis and water status in female and male Populus cathayana: implications for sex-specific drought and heat tolerances
Authors: Liu Junyan , Zhang Rong , Xu Xiao , Fowler Joshua C , Miller Tom E X , Dong Tingfa
Published: June 2020

Effects of climate warming on tree growth and physiology may be driven by direct thermal effects and/or by changes in soil moisture. Dioecious tree species usually show sexual spatial segregation along abiotic gradients; however, few studies have assessed the sex-specific responses to warming in dioecious trees. We investigated the sex-specific responses in growth, photosynthesis, nonstructural carbohydrate (NSC), water-use efficiency and whole-plant hydraulic conductance (KP) of the dioecious tree species Populus cathayana Rehd. under +4 °C elevated temperature with and without supplemental water. For both sexes, high-temperature treatments significantly decreased growth (height and biomass), photosynthetic rate (A), the ratio of A to dark respiration rate, stomatal conductance (gs), transpiration rate, NSC, leaf water potential and KP, but increased water-use efficiency (estimated from carbon isotope composition). Under warming with supplemental water, most traits of females did not change relative to ambient conditions, but traits of males decreased, resulting in greater sexual differences. Females showed a lower KP, and their gs and A responded more steeply with water-related traits than males. These results show that the effect of summer warming on growth and photosynthesis was driven mainly by soil moisture in female P. cathayana, while male performance was mainly related to temperature. Females may experience less thermal stress than males due to flexible water balance strategy via stomata regulation and water use.
An improved method for quantifying total fine root decomposition in plantation forests combining measurements of soil coring and minirhizotrons with a mass balance model
Authors: Li Xuefeng , Minick Kevan J , Li Tonghua , Williamson James C , Gavazzi Michael , McNulty Steven , King John S
Published: June 2020

Accurate measurement of total fine root decomposition (the amount of dead fine roots decomposed per unit soil volume) is essential for constructing a soil carbon budget. However, the ingrowth/soil core-based models are dependent on the assumptions that fine roots in litterbags/intact cores have the same relative decomposition rate as those in intact soils and that fine root growth and death rates remain constant over time, while minirhizotrons cannot quantify the total fine root decomposition. To improve the accuracy of estimates for total fine root decomposition, we propose a new method (balanced hybrid) with two models that integrate measurements of soil coring and minirhizotrons into a mass balance model. Model input parameters were fine root biomass, necromass and turnover rate for Model 1, and fine root biomass, necromass and death rate for Model 2. We tested the balanced hybrid method in a loblolly pine plantation forest in coastal North Carolina, USA. The total decomposition rate of absorptive fine roots (ARs) (a combination of first- and second-order fine roots) using Models 1 and 2 was 107 ± 13 g m−2 year−1 and 129 ± 12 g m−2 year−1, respectively. Monthly total AR decomposition was highest from August to November, which corresponded with the highest monthly total ARs mortality. The ARs imaged by minirhizotrons well represent those growing in intact soils, evident by a significant and positive relationship between the standing biomass and the standing length. The total decomposition estimate in both models was sensitive to changes in fine root biomass, turnover rate and death rate but not to change in necromass. Compared with Model 2, Model 1 can avoid the technical difficulty of deciding dead time of individual fine roots but requires greater time and effort to accurately measure fine root biomass dynamics. The balanced hybrid method is an improved technique for measuring total fine root decomposition in plantation forests in which the estimates are based on empirical data from soil coring and minirhizotrons, moving beyond assumptions of traditional approaches.
Hip Fracture Outcomes During the COVID-19 Pandemic: Early Results From New York
Authors: LeBrun Drake G. , Konnaris Maxwell A. , Ghahramani Gregory C. , Premkumar Ajay , DeFrancesco Chris J. , Gruskay Jordan A. , Dvorzhinskiy Aleksey , Sandhu Milan S. , Goldwyn Elan M. , Mendias Christopher L. , Ricci William M.
Published: June 2020

Objective:

To evaluate inpatient outcomes among patients with hip fracture treated during the COVID-19 pandemic in New York City.

Design:

Multicenter retrospective cohort study.

Setting:

One Level 1 trauma center and one orthopaedic specialty hospital in New York City.

Patients/Participants:

Fifty-nine consecutive patients (average age 85 years, range: 65–100 years) treated for a hip fracture (OTA/AO 31, 32.1) over a 5-week period, March 20, 2020, to April 24, 2020, during the height of the COVID-19 crisis.

Main Outcome Measurements:

COVID-19 infection status was used to stratify patients. The primary outcome was inpatient mortality. Secondary outcomes were admission to the intensive care unit, unexpected intubation, pneumonia, deep vein thrombosis, pulmonary embolus, myocardial infarction, cerebrovascular accident, urinary tract infection, and transfusion. Baseline demographics, comorbidities, treatment characteristics, and COVID-related symptomatology were also evaluated.

Results:

Ten patients (15%) tested positive for COVID-19 (COVID+) (n = 9; 7 preoperatively and 2 postoperatively) or were presumed positive (n = 1), 40 (68%) patients tested negative, and 9 (15%) patients were not tested in the primary hospitalization. American Society of Anesthesiologists' scores were higher in the COVID+ group (d = −0.83; P = 0.04); however, the Charlson Comorbidity Index was similar between the study groups (d = −0.17; P = 0.63). Inpatient mortality was significantly increased in the COVID+ cohort (56% vs. 4%; odds ratio 30.0, 95% confidence interval 4.3–207; P = 0.001). Including the one presumed positive case in the COVID+ cohort increased this difference (60% vs. 2%; odds ratio 72.0, 95% confidence interval 7.9–754; P < 0.001).

Conclusions:

Hip fracture patients with concomitant COVID-19 infection had worse American Society of Anesthesiologists' scores but similar baseline comorbidities with significantly higher rates of inpatient mortality compared with those without concomitant COVID-19 infection.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Comminuted Fibular Head Fractures With Posterolateral Knee Instability: A Novel Repair Technique Using a Tension-Slide Device
Authors: Cinats David J. , Stone Trevor
Published: June 2020

Comminuted proximal fibula fractures or arcuate fractures (OTA/AO 4F1B fractures) can defunction the posterolateral corner (PLC) and result in posterolateral knee instability. Ongoing posterolateral knee instability can limit function, cause significant pain, and lead to early knee arthrosis. The anatomy of the PLC and proximal fibula limits the options for repair of this injury. The ideal method for osteosynthesis of these injuries has not been established. The goals of treatment include reconstitution of posterolateral stability, restoration of the anatomic relationship of PLC structures, and restoration of bone stock that would permit future reconstruction. This article characterizes the injury pattern, outlines the technique, and provides the clinical and radiographic outcomes of osteosynthesis of comminuted fibular head fractures using a novel application of the tension-slide technique.
Emission of Ultraviolet Radiation from 220 to 280 NM by a Cold Physical Plasma Generating Device
Authors: Kletschkus Karsten , Gelbrich Nadine , Burchardt Martin , Kramer Axel , Bekeschus Sander , Stope Matthias B.
Published: June 2020

The generation of cold physical plasma at atmospheric pressure (cold atmospheric plasma: CAP) generates different reactive molecular species as well as radiation in the ultraviolet (UV) range. The therapy of tumor diseases has proven to be a new promising area of application for CAP treatment. With regard to the routine use of CAP in cancer therapy, however, application safety must be ensured both for the patient and for the operator. In this study, the intensity of UVC radiation of the CAP device MiniJet-R (HF Technik, Aachen, Germany) was measured in the range from 220 to 280 nm depending on various device-specific parameters. Depending on the distance to the CAP flame, the UVC intensity reaches values up to 124.5±11 mW m−2. It should be noted here that the UVC radiation generated by the CAP is emitted in all orientations in the room but is also shielded by the geometry of the handpiece of the CAP device. The device-specific settings for the flow rate of the carrier gas, argon, and the power level at the high-frequency (HF) generator of the CAP device also influence the intensity of the UVC radiation. With regard to the medical use of the CAP device, it can be stated that there is an exposure to UVC radiation, which, depending on the duration of treatment, can also be above the maximum value legally specified in Europe. Shielding components on the CAP device can reduce UVC exposure to the operator as well as adverse side effects to the patient.
Long-Term Maintenance of Corneal Endothelial Cell Density After Corneal Transplantation
Authors: Kayukawa Kanae , Kitazawa Koji , Wakimasu Koichi , Patel Sanjay V. , Bush John , Sotozono Chie , Kinoshita Shigeru
Published: May 2020

Purpose:

To investigate the key factors associated with eyes with an endothelial cell density (ECD) of ≥2000 cells/mm2 at 5 years after corneal transplantation.

Methods:

This retrospective cohort study included 174 eyes that underwent penetrating keratoplasty by 1 corneal specialist surgeon at the Baptist Eye Institute, Kyoto, Japan, from 1998 through 2011 and that were carefully followed for over 5 years postoperative. In all operated eyes, corneal ECD was measured at 1, 2, 3, 4, and 5 years postoperative. Multivariate analysis with adjustment for preoperative donor ECD was performed between eyes with an ECD of ≥2000 cells/mm2 and those with an ECD of <2000 cells/mm2 at 5 years postoperative.

Results:

Of the 174 eligible eyes, 16 eyes (9.2%) had an ECD of ≥2000 cells/mm2 at 5 years postoperative, and the annual rate of endothelial cell loss (mean ± SD) was 2.3% ± 3.7%. Multivariate analysis findings revealed that the donor-associated and surgery-related factors were not significant factors. Only the recipient diagnosis of bullous keratopathy was significantly associated with an ECD of <2000 cells/mm2 at 5 years postoperative. Of those 16 eyes, 6 (37.5%) had a recipient diagnosis of bullous keratopathy.

Conclusions:

None of the donor- and surgery-related factors, previously recognized as associated with a lower endothelial cell loss after penetrating keratoplasty, were found to be significant in this study, thus suggesting that there are still unknown factors associated with maintaining a higher ECD over the long-term postoperative period.
Slip-and-slide technique for combined small-incision artificial iris and IOL implantation
Authors: Wolf Armin , Shajari Mehdi
Published: June 2020

A surgical technique is described for reducing surgically induced astigmatism (SIA) during combined implantation of IOL and artificial iris. The CUSTOMFLEX ARTIFICIALIRIS was implanted in 2 patients who suffered from aphakia and complete traumatic aniridia. Implantation of the prosthesis was accompanied by insertion of an IOL that was fixed at the iris implant. Although prosthesis and IOL can be implanted through small incisions individually, the combined package usually requires a larger incision causing greater SIA. The new technique minimizes the SIA because both components are fixed together but can be inserted separately. Final assembling of the iris–IOL package is performed after separate implantation. The technique to implant the artificial iris combined with a nontoric or a toric IOL is described. The slip-and-slide technique was a safe and an effective way to implant an iris–IOL package while keeping the SIA small and reducing the incision size.
Historical and Current Perspectives of Synthetic Marijuana
Authors: Vera Lisa , Bernstein Kunsook , Lee Seatbyul
Published: May 2020

Synthetic marijuana use has increased significantly since 2008 among young adults in the United States, as have adverse reactions to it, leading to a dramatic increase in emergency department visits. However, much of the research conducted on it has been case studies, which report detrimental symptoms on an individual basis. Only a limited number of studies aim to better understand the larger parameters of this epidemic to assist health care providers and policy makers, including early detection, intervention, and adequate treatment. In addition, there has been limited critical review of this substance to help health care professionals educate the public about the negative health effects of using this drug. This article explores the critical reviews of synthetic marijuana, also commonly known as “K2” and “Spice,” synthesizing information from literature reviews, case studies, media information, and government websites. Findings were organized by synthetic marijuana's history, description, adverse reactions including withdrawal symptoms and death incidents, detection screening, treatment, and legislative issues. Health care providers need to understand the detrimental effects of this illicit and harmful substance to both the body and mind and sometimes irreversible damage caused to individuals who consume it. Policy makers, the public, and affected individuals and their family members need to be educated as well.
A Mixed Methods Pilot Study on the Short-Term Physiological Effects of Vaping and Attitudes Regarding Its Use and Health Effects in Samples of Young Adults
Authors: McClelland Molly , Sesoko Channing , MacDonald Douglas A.
Published: May 2020

Vaping is a fairly new and legal way young people are inhaling substances into their lungs. Very little is currently known about the immediate physiological impact or the psychosocial reasons surrounding vape use. This study used a mixed methods approach to (a) understand the short-term physiological implications of vape use compared with people who do not vape and (b) investigate the reasons people choose to vape compared with those who choose not to vape. Twenty-four people participated in the study: 12 self-identified as nonvapers, and 12 self-identified as people who vape. All participants were between 18 and 24 years old. Qualitative analysis suggested people vape because they think it is cool, think it is less risky than smoking, and enjoy the social aspects of vaping. People who choose not to vape are concerned about the unknown health implications, think it is a waste of resources, and are apathetic toward it. Quantitative results revealed statistically significant increases in heart rate and decreases in the percentage of blood oxygenation after 20 minutes of vape use. Blood pressure, respiratory rate, and blood sugar scores did not significantly change after 20 minutes of vape use. Differences in the frequencies of men and women across the two groups were found. Significant differences found for systolic blood pressure, respiratory rate, and pulmonary function test became nonsignificant after controlling for gender. Both long- and short-term effects of vaping need to be further evaluated. The psychosocial reasons why certain people vape whereas others in the same peer group do not also need to be better understood.
Screening for Adolescent Use of Electronic Nicotine Delivery Systems
Authors: Palmer Joshua , Nativio Donna
Published: May 2020

Electronic Nicotine Delivery Systems (ENDS) are a new form of tobacco and marijuana administration that obscures the dangers of substance use and can be appealing to adolescents with a multitude of adolescent appeals and the use of electronic technology. As adolescent incidence of ENDS uses increases, health providers stand to lose ground with the past successes of tobacco- and substance-related health promotion as adolescents are initiated with the new technology. These risks identify the need for quality screening or the specific inclusion of ENDS products into our established screening methods. In addition, those who screen positive are provided quality interventions, such as motivational interviewing, that are effective and developmentally appropriate. By increasing our knowledge of ENDS, including them specifically in our regular screenings, and supporting adolescents in positive health choices, successful aversion of lifelong health risks can be overcome.
Spontaneous Intracranial Hypotension May Be an Under-recognized Cause of Endolymphatic Hydrops
Authors: Sakano Hitomi , Jafari Aria , Allehaiby Wisam , Harris Jeffrey P.
Published: May 2020

Objective:

We describe three rare cases of spontaneous intracranial hypotension (SIH) presenting with symptoms of endolymphatic hydrops (EH) and perform a literature review to bring attention to a rare link between SIH and EH.

Patient:

A 59-year-old female presented with postural headache, aural fullness, vertigo, hearing loss, and abnormal electrocochleography after being diagnosed with SIH by magnetic resonance imaging. The site of cerebrospinal fluid leak was identified in this individual. Two additional patients with vertigo, hearing loss, and SIH were identified by retrospective chart review.

Intervention:

All patients underwent blood patches. One patient also had diuretic treatment while another had fibrin glue injection.

Main Outcome Measures:

The outcomes of interest were resolution of headache, vertigo, aural fullness, and hearing loss.

Results:

All patients eventually improved with time. Literature review suggests that overall outcome is excellent.

Conclusions:

SIH may be an under-recognized cause of EH. We support the theory that negative intracranial pressure transmitted through the cochlear aqueduct and perilymph leads to EH. Despite the variations in treatments, the overall prognosis is excellent.
Patients With Inflammatory Bowel Diseases Are at Higher Risk for Meningitis
Authors: Kochar Bharati , Jiang Yue , Long Millie D.
Published: June 2020

Background:

The epidemiology of meningitis is unknown in inflammatory bowel disease (IBD) patients.

Goals:

We aimed to determine the incidence of and risk factors for meningitis in IBD patients.

Study:

We conducted a retrospective cohort and nested case-control study in the Quintiles IMS Legacy PharMetrics Adjudicated Claims Database from January 2001 to June 2016. We matched IBD patients to those without IBD on age, sex, enrollment, and region. Meningitis was defined as one code for meningitis associated with an emergency department visit or hospitalization. Meningitis risk was calculated with incidence rate ratios. In a nested case-control study of IBD patients, predictors for meningitis were determined with multivariable conditional logistic regression models.

Results:

We identified 50,029 patients with Crohn’s disease (CD) and 59,830 patients with ulcerative colitis (UC) matched to 296,801 non-IBD comparators. There were 85 CD patients, 77 UC patients, and 235 comparators with meningitis. CD patients had 2.17 times the rate of meningitis and UC patients had 1.63 times the rate of meningitis as non-IBD comparators. After adjusting for relevant covariates among those with IBD, treatment with mesalamine was associated with a significantly lower odds of a meningitis claim (odds ratio: 0.40, 95% confidence interval: 0.26-0.62). Having at least one comorbidity was associated with a significantly higher odds of a meningitis claim (odds ratio: 2.21, 95% confidence interval: 1.76-2.77).

Conclusions:

Although the overall rate of meningitis is low, IBD patients are at an increased risk compared with non-IBD comparators. Comorbidities are a risk factor for meningitis in IBD patients. Pneumococcal and meningococcal vaccinations should be discussed.
On-Campus Clinical
Authors: Mannino Jennifer Emilie , Lane Mary , Siegel Victoria , Osborne Jean Marie , O'Hara Susan
Published: June 2020

Background

Ensuring students are both confident and competent for clinical practice will lead to improved patient outcomes. Early exposure to delivering safe and effective care using knowledge, skills, and abilities that are consonant with professional practice is essential.

Problem

Caring for an increasingly complex patient population is challenging. Entry-to-practice competencies must begin early in the student's education and be developed throughout.

Approach

This educational initiative outlines an innovative and a collaborative evidence-based learning experience that prepares prelicensure nursing students to deliver safe and effective patient-centered care during their first clinical practice. Lecture and laboratory topics, clinical skills stations, and simulation scenarios were developed to promote critical thinking and clinical judgment in a complex health care environment.

Outcomes

More than 2300 first-year clinical students, instructors, and staff participated in this rigorous course-wide experience.

Conclusion

This 1-day immersion cultivates safe practice and may be incorporated throughout the curriculum as students encounter increasingly challenging clinical practice experiences.
Noninvasive Approaches for Anxiety Reduction During Interventional Radiology Procedures
Authors: Makary Mina S. , da Silva Alexandre , Kingsbury James , Bozer Jordan , Dowell Joshua D. , Nguyen Xuan V.
Published: May 2020

Periprocedural anxiety is a major cause of morbidity, particularly for interventional radiology procedures that often depend on conscious sedation. Management of anxiety and pain during image-guided procedures has traditionally relied on pharmacologic agents such as benzodiazepines and opioids. Although generally safe, use of these medications risks adverse events, and newer noninvasive, nonpharmacologic techniques have evolved to address patient needs. In this review, we explore the roles of hypnosis, structured empathic attention, anodyne imagery, music, video glasses, and mobile applications in reducing procedural anxiety and pain with the goal of improving patient satisfaction, operational efficiency, and clinical outcomes.
The Influence of Obesity on Outcomes After Pediatric Reduction Mammaplasty
Authors: Fairchild Berry , Wei Shuyan , Bartz-Kurycki Marisa , Rose Jessica F. , Greives Matthew R.
Published: May 2020

Background

Symptomatic macromastia causes negative physical and psychosocial effects, which support the need for early intervention, even in the adolescent population (Plast Reconstr Surg 2012;130:785–789). Reduction mammaplasty is a proven treatment that reliably addresses symptoms from macromastia. The National Surgical Quality Improvement Program–Pediatric is the leading nationally validated, risk-adjusted, outcomes-based program to measure and improve the quality of surgical care (Pediatrics 2012;130:e339–e346). In adults, obesity is associated with increased early postoperative complications after mammaplasty (Pediatrics 2017;140(5)). We hypothesized that obesity would increase the incidence of postoperative complications in pediatric patients undergoing reduction mammaplasty.

Methods

The National Surgical Quality Improvement Program–Pediatric database was queried for female patients 18 years or younger who underwent reduction mammaplasty from January 2012 to December 2017 using Current Procedural Terminology code 19318. Demographic, clinical, and outcomes data were abstracted from the database. A composite postoperative adverse events variable was created from a list of 21 individual adverse events. Patients were stratified by presence of obesity (body mass index ≥30 kg/m2) on univariate analyses. Multivariable logistic regression was used to determine factors associated with any postoperative adverse events.

Results

A total of 542 female patients underwent reduction mammaplasty, with 48% of the cohort being obese. Patients were similar in age (median, 17 years) and comorbidities between obese and nonobese groups. Obese patients were more likely to be African American, have higher American Society of Anesthesiologists class, and endure longer operations. Composite adverse event rates were significantly higher in the obese group (7% vs 2%, P = 0.013). Individual adverse events were similar between groups, with the exception of 30-day readmissions, which was higher in the obese group (3% vs 1%, P = 0.04). On multivariable logistic regression, obesity increased the odds of having a postoperative adverse event by 3-fold after adjusting for operative duration.

Conclusions

Obesity was significantly associated with greater postoperative adverse events in obese adolescent females after reduction mammaplasty compared with their nonobese counterparts. Although recorded rates of adverse events after reduction mammaplasty were low, preoperative weight loss programs may further improve outcomes for obese pediatric populations undergoing reduction mammaplasty.