bluuebunny/crossref_metadata_2025 huggingface dataset:
Leaf area index in Earth system models: how the key variable of vegetation seasonality works in climate projections
Authors: Park Hoonyoung , Jeong Sujong
Published: February 2021

Earth system models (ESMs) are widely used in scientific research to understand the responses of various components of Earth systems to natural and anthropogenic forcings. ESMs embody terrestrial ecosystems on the basis of the leaf area index (LAI) to formulate various interactions between the land surface and atmosphere. Here, we evaluated the LAI seasonality of deciduous forests simulated by 14 ESMs participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and CMIP6 to understand the efficacy of recent ESMs in describing leaf dynamics in the northern extratropics from 1982 to 2014. We examined three indicators of LAI seasonality (annual mean, amplitude, and phase) and three phenological dates (start (SOS), end (EOS), and length of growing season (LOS)) of the models in comparison to the third-generation LAI of Global Inventory Modeling and Mapping Studies (GIMMS LAI3g) and the Climate Research Unit gridded time series dataset. CMIP6 models tend to simulate larger annual means (1.7 m2 m−2), weaker amplitudes (0.9 m2 m−2), and delayed phases (226 DOY) compared to the GIMMS LAI3g (1.2 m2 m−2, 1.2 m2 m−2, and 212 DOY, respectively), yet are similar to the CMIP5 models (2.2 m2 m−2, 1.0 m2 m−2, and 225 DOY). The later phase is attributed to a systematic positive bias in EOS of the CMIP5 and CMIP6 models (later by 22 and 18 d, respectively) compared to the GIMMS LAI3g (261 DOY). Further tests on phenological responses to seasonal temperature revealed that the majority of CMIP5 and CMIP6 ESMs inaccurately describe the sensitivities of SOS and EOS to seasonal temperature and the recent changes in mean SOS and EOS distributions (2005–2014 minus 1982–1991). This study suggests that phenology schemes of deciduous forests, especially for autumn leaf senescence, should be revisited to achieve an accurate representation of terrestrial ecosystems and their interactions.
A review on the status and development of hyperaccumulator harvests treatment technology
Authors: Fu Yongzhen , You Shaohong , Luo Xiangpin
Published: February 2021

Phytoremediation is a low cost and green remediation technology, which is widely used in remediation of soil polluted by heavy metals such as cadmium and manganese. However, with the extension and implementation of phytoremediation technology in soil remediation, the disposal of a large number of hyperaccumulator plant harvests has become a hot topic in the field of phytoremediation. These harvests generally contain high concentrations of heavy metals, which can cause secondary contamination if improperly disposed of. This paper reviews the traditional disposal techniques that can be processed by composting process, compaction landfill, Liquid phase extraction, incineration, Ashing and Pyrolysis as well as emerging resource disposal technologies such as phytomining and supercritical water technology and identifies current issues with phytoremediation plants disposal. The possible research directions in the future are also prospected.
Genetic inference of the mating system of free-ranging domestic dogs
Authors: Natoli Eugenia , Bonanni Roberto , Cafazzo Simona , Mills Daniel S , Pontier Dominique , Pilot Małgorzata
Published: February 2021

Domestication has greatly changed the social and reproductive behavior of dogs relative to that of wild members of the genus Canis, which typically exhibit social monogamy and extended parental care. Unlike a typical gray wolf pack that consists of a single breeding pair and their offspring from multiple seasons, a group of free-ranging dogs (FRDs) can include multiple breeding individuals of both sexes. To understand the consequences of this shift in reproductive behavior, we reconstructed the genetic pedigree of an FRD population and assessed the kinship patterns in social groups, based on genome-wide single-nucleotide polymorphism genotypes. Consistent with behavioral observations, the mating system of the study population was characterized by polygynandry. Instead of the discreet family units observed in wolves, FRDs were linked by a network of kinship relationships that spread across packs. However, we also observed reproduction of the same male–female pairs in multiple seasons, retention of adult offspring in natal packs, and dispersal between neighboring packs—patterns in common with wolves. Although monogamy is the predominant mating system in wolves, polygyny and polyandry are occasionally observed in response to increased food availability. Thus, polygynandry of domestic dogs was likely influenced by the shift in ecological niche from an apex predator to a human commensal.
Inflated false discovery rate due to volcano plots: problem and solutions
Authors: Ebrahimpoor Mitra , Goeman Jelle J
Published: February 2021

Motivation

Volcano plots are used to select the most interesting discoveries when too many discoveries remain after application of Benjamini–Hochberg’s procedure (BH). The volcano plot suggests a double filtering procedure that selects features with both small adjusted $P$-value and large estimated effect size. Despite its popularity, this type of selection overlooks the fact that BH does not guarantee error control over filtered subsets of discoveries. Therefore the selected subset of features may include an inflated number of false discoveries.

Results

In this paper, we illustrate the substantially inflated type I error rate of volcano plot selection with simulation experiments and RNA-seq data. In particular, we show that the feature with the largest estimated effect is a very likely false positive result. Next, we investigate two alternative approaches for multiple testing with double filtering that do not inflate the false discovery rate. Our procedure is implemented in an interactive web application and is publicly available.
Spawning substrate shift associated with the evolution of a female sexual characteristic in a family of fishes
Authors: Styga Joseph M , Welsh Daniel P
Published: February 2021

Because ‘primary’ sexual characteristics (i.e. those directly associated with reproduction) can be extremely variable, evolve quickly, and can be impacted by both natural and sexual selection, they are often considered excellent model systems in which to study evolution. Here, we explore the evolution of the anal sheath, a trait hypothesized to facilitate the release and proper placement of eggs on the spawning substrate, and its relationship to spawning habitat and maximum body size in a family of fish (Fundulidae). In addition to using phylogenetically informed statistics to determine the role of preferred spawning habitat and maximum body size on the evolution of anal sheath length, we reconstruct the evolutionary history of the anal sheath and preferred spawning habitat. We then test for significant phylogenetic signal and evolutionary rate shifts in the size of the anal sheath and the preferred spawning habitat. Our results indicate that preferred spawning habitat, and not maximum body length, significantly influences anal sheath size, which is associated with a significant phylogenetic signal, and an evolutionary rate similar to that of preferred spawning substrate. We discuss these results in terms of potential evolutionary mechanisms driving anal sheath length.
The Concept, Practice, Application, and Results of Locally Based Monitoring of the Environment
Authors: Danielsen Finn , Enghoff Martin , Poulsen Michael K , Funder Mikkel , Jensen Per M , Burgess Neil D
Published: February 2021

Locally based monitoring is typically undertaken in areas in which communities have a close attachment to their natural resource base. We present a summary of work to develop a theoretical and practical understanding of locally based monitoring and we outline tests of this approach in research and practice over the past 20 years. Our tests show that locally based monitoring delivers credible data at local scale independent of external experts and can be used to inform local and national decision making within a short timeframe. We believe that monitoring conducted by and anchored in communities will gain in importance where scientist-led monitoring is sparse or too expensive to sustain and for ecosystem attributes in cases in which remote sensing cannot provide credible data. The spread of smartphone technology and online portals will further enhance the importance and usefulness of this discipline.
Characteristics and Outcome of Acute Heart Failure in Infective Endocarditis: Focus on Cardiogenic Shock
Authors: Pericàs Juan M , Hernández-Meneses Marta , Muñoz Patricia , Martínez-Sellés Manuel , Álvarez-Uria Ana , de Alarcón Arístides , Gutiérrez-Carretero Encarnación , Goenaga Miguel A , Zarauza Manuel J , Falces Carlos , Rodríguez-Esteban M Ángeles , Hidalgo-Tenorio Carmen , Hernández-Cabrera Michele , Miró Jose M ,   Spanish Collaboration on Endocarditis—Grupo de Apoyo al Manejo de la Endocarditis Infecciosa en España (GAMES)
Published: February 2021

Background

Studies investigating the impact of cardiogenic shock (CS) on endocarditis are lacking.

Methods

Prospectively collected cohort from 35 Spanish centers (2008-2018). Logistic regression analyses were performed to identify risk factors for developing CS and predictors of mortality.

Results

Among 4856 endocarditis patients, 1652 (34%) had acute heart failure (AHF) and 244 (5%) CS. Compared with patients without AHF and AHF but no CS, patients with CS presented higher rates of surgery (40.5%, 52.5%, and 68%; P < .001) and in-hospital mortality (16.3%, 39.1%, and 52.5%). Compared with patients with septic shock, CS patients presented higher rates of surgery (42.5% vs 68%; P < .001) and lower rates of in-hospital and 1-year mortality (62.3% vs 52.5%, P = .008, and 65.3% vs 57.4%, P = .030). Severe aortic and mitral regurgitation (OR [95% CI], 2.47 [1.82-3.35] and 3.03 [2.26-4.07]; both P < .001), left-ventricle ejection fraction <60% (1.72; 1.22-2.40; P = .002), heart block (2.22; 1.41-3.47; P = .001), tachyarrhythmias (5.07; 3.13-8.19; P < .001), and acute kidney failure (2.29; 1.73-3.03; P < .001) were associated with higher likelihood of developing CS. Prosthetic endocarditis (2.03; 1.06 -3.88; P = .032), Staphylococcus aureus (3.10; 1.16 -8.30; P = .024), tachyarrhythmias (3.09; 1.50-10.13; P = .005), and not performing cardiac surgery (11.40; 4.83-26.90; P < .001) were associated with a higher risk of mortality.

Conclusions

AHF is common among patients with endocarditis. CS is associated with high mortality and should be promptly identified and assessed for cardiac surgery.
Gitelman syndrome and ectopic calcification in the retina and joints
Authors: Ham Yeji , Mack Heather , Colville Deb , Harraka Philip , Savige Judy
Published: February 2021

Gitelman syndrome is a rare inherited renal tubular disorder with features that resemble thiazide use, including a hypokalemic metabolic alkalosis, hypomagnesemia, hypocalciuria and a low or normal blood pressure, hyperreninemia and hyperaldosteronism. Treatment is primarily correction of the potassium and magnesium levels. The diagnosis is confirmed with genetic testing but Gitelman syndrome is often not suspected. However, the association with ectopic calcification in the retina, blood vessels and chondrocalcinosis in the joints is a useful pointer to this diagnosis. Bilateral symmetrical whitish deposits of calcium pyrophosphate are visible superotemporally on ophthalmoscopy and retinal photography but are actually located beneath the retina in the sclerochoroid. Optical coherence tomography is even more sensitive for their detection. These deposits increase in size with time, but the rate of progression slows with long-term correction of the hypomagnesemia. Calcification may be complicated by atrophy of the overlying retina and visual loss. The deposits often correlate with ectopic calcification in the aorta and coronary and cerebral vessels. Chondrocalcinosis occurs in the large joints such as the knees. Ectopic calcification in Gitelman syndrome indicates the need for more aggressive management of Mg levels. Calcification is much less common in Bartter syndrome, which itself is rarer and associated less often with hypomagnesemia.
Engagement of Children who are Deaf or Hard-of-Hearing Attending Mainstream Schools
Authors: Todorov Michelle , Galvin Karyn , Klieve Sharon , Rickards Field
Published: February 2021

This study compared the observed and the self-reported engagement of 16 students who are Deaf or hard-of-hearing (DHH) attending mainstream schools to that of matched controls with typical hearing. Observed engagement was measured through observations in the classroom setting using the Mainstream Version of the Code for Instructional Structure and Student Academic Reponses. Self-reported engagement was measured using the Classroom Participation Questionnaire. The results revealed no significant differences for either observed or self-reported engagement between the DHH and the control groups; however, three individual DHH participants had lower levels of observed engagement compared to their matched controls. As such, including engagement in the evaluation of students who are DHH may be important for some individuals to provide a better understanding of the daily challenges they experience at school. Where needs are identified, the support that students who are DHH receive should include a specific focus on engagement to assist with their successful inclusion.
Is total aortic arch replacement with the frozen elephant trunk procedure reasonable in elderly patients?
Authors: Beckmann Erik , Martens Andreas , Kaufeld Tim , Natanov Ruslan , Krueger Heike , Haverich Axel , Shrestha Malakh
Published: February 2021

OBJECTIVES

Total aortic arch replacement is an invasive procedure with significant risks for complications. These risks are even higher in older, multimorbid patients. The current trends in demographic changes in western countries with an ageing population will aggravate this issue. In this study, we present our experience with total aortic arch replacement using the frozen elephant trunk (FET) technique in septuagenarians. We compared the results of septuagenarians with those of younger patients and analysed if there was an improvement in outcome over time.

METHODS

Between August 2001 and March 2020, 225 patients underwent non-urgent FET procedure at our institution. There were 75 patients aged ≥70 years (mean age 74 ± 4) who were assigned to group A, and 150 patients aged <70 years (mean age of 57 ± 11) who were assigned to group B. In groups A and B, the indications for surgery were chronic dissection (21% vs 53%), aortic aneurysm (78% vs 45%) and penetrating atherosclerotic ulcer (1% vs 2%).

RESULTS

The rate for temporary dialysis was significantly higher in group A than in group B (29% vs 13%, P = 0.003), although the majority recovered kidney function. Rates for re-exploration for bleeding and stroke were comparable in both groups. In-hospital mortality was significantly higher in group A than in group B (24% vs 13%, P = 0.037). Logistic regression analysis showed that age >70 years was an independent statistically significant risk factor for in-hospital mortality (odds ratio = 2.513, 95% confidence interval = 1.197–5.278, P-value = 0.015). Follow-up was complete for 100% of patients and comprised a total of 1073 patient-years with a mean follow-up time of 4.8 ± 4.5 years. The 1- and 5-year survival rates were 68% and 49% in group A, and 85% and 71% in group B, respectively (log rank, P < 0.001). Survival did not significantly improve over time.

Discussion

Total aortic arch replacement using the FET technique has a significantly higher risk for perioperative morbidity and mortality in septuagenarians than in younger patients. Long-term survival is significantly impaired in older patients. We recommend thorough patient selection of those who require total aortic arch replacement, and optimization of perioperative management to improve outcomes.
Patterns of myocardial injury in recovered troponin-positive COVID-19 patients assessed by cardiovascular magnetic resonance
Authors: Kotecha Tushar , Knight Daniel S , Razvi Yousuf , Kumar Kartik , Vimalesvaran Kavitha , Thornton George , Patel Rishi , Chacko Liza , Brown James T , Coyle Clare , Leith Donald , Shetye Abhishek , Ariff Ben , Bell Robert , Captur Gabriella , Coleman Meg , Goldring James , Gopalan Deepa , Heightman Melissa , Hillman Toby , Howard Luke , Jacobs Michael , Jeetley Paramjit S , Kanagaratnam Prapa , Kon Onn Min , Lamb Lucy E , Manisty Charlotte H , Mathurdas Palmira , Mayet Jamil , Negus Rupert , Patel Niket , Pierce Iain , Russell Georgina , Wolff Anthony , Xue Hui , Kellman Peter , Moon James C , Treibel Thomas A , Cole Graham D , Fontana Marianna
Published: February 2021

Background

Troponin elevation is common in hospitalized COVID-19 patients, but underlying aetiologies are ill-defined. We used multi-parametric cardiovascular magnetic resonance (CMR) to assess myocardial injury in recovered COVID-19 patients.

Methods and results

One hundred and forty-eight patients (64 ± 12 years, 70% male) with severe COVID-19 infection [all requiring hospital admission, 48 (32%) requiring ventilatory support] and troponin elevation discharged from six hospitals underwent convalescent CMR (including adenosine stress perfusion if indicated) at median 68 days. Left ventricular (LV) function was normal in 89% (ejection fraction 67% ± 11%). Late gadolinium enhancement and/or ischaemia was found in 54% (80/148). This comprised myocarditis-like scar in 26% (39/148), infarction and/or ischaemia in 22% (32/148) and dual pathology in 6% (9/148). Myocarditis-like injury was limited to three or less myocardial segments in 88% (35/40) of cases with no associated LV dysfunction; of these, 30% had active myocarditis. Myocardial infarction was found in 19% (28/148) and inducible ischaemia in 26% (20/76) of those undergoing stress perfusion (including 7 with both infarction and ischaemia). Of patients with ischaemic injury pattern, 66% (27/41) had no past history of coronary disease. There was no evidence of diffuse fibrosis or oedema in the remote myocardium (T1: COVID-19 patients 1033 ± 41 ms vs. matched controls 1028 ± 35 ms; T2: COVID-19 46 ± 3 ms vs. matched controls 47 ± 3 ms).

Conclusions

During convalescence after severe COVID-19 infection with troponin elevation, myocarditis-like injury can be encountered, with limited extent and minimal functional consequence. In a proportion of patients, there is evidence of possible ongoing localized inflammation. A quarter of patients had ischaemic heart disease, of which two-thirds had no previous history. Whether these observed findings represent pre-existing clinically silent disease or de novo COVID-19-related changes remain undetermined. Diffuse oedema or fibrosis was not detected.
Breast milk urea as a nitrogen source for urease positiveBifidobacterium infantis
Authors: Schimmel Patrick , Kleinjans Lennart , Bongers Roger S , Knol Jan , Belzer Clara
Published: February 2021

Human milk stimulates a health-promoting gut microbiome in infants. However, it is unclear how the microbiota salvages and processes its required nitrogen from breast milk. Human milk nitrogen sources such as urea could contribute to the composition of this early life microbiome. Urea is abundant in human milk, representing a large part of the non-protein nitrogen (NPN). We found that B. longum subsp. infantis (ATCC17930) can use urea as a main source of nitrogen for growth in synthetic medium and enzyme activity was induced by the presence of urea in the medium. We furthermore confirmed the expression of both urease protein subunits and accessory proteins of B. longum subsp. infantis through proteomics. To the same end, metagenome data were mined for urease-related genes. It was found that the breastfed infant's microbiome possessed more urease-related genes than formula fed infants (51.4:22.1; 2.3-fold increase). Bifidobacteria provided a total of 106 of urease subunit alpha alignments, found only in breastfed infants. These experiments show how an important gut commensal that colonizes the infant intestine can metabolize urea. The results presented herein further indicate how dietary nitrogen can determine bacterial metabolism in the neonate gut and shape the overall microbiome.
A new method for estimating the correlation of seismic waveforms based on the NTFT
Authors: Cheng Wei , Liu Lintao , Wang Guocheng
Published: February 2021

We propose a new correlation function called the similarity coefficient (SC) based on the normal time–frequency transform (NTFT) to evaluate the similarity between two non-stationary seismic signals as a function of the delay time. The SC is defined in the time–frequency spectrum of the NTFT, and the instantaneous phase and amplitude of each frequency component in a signal are used to calculate the SC. Our simulation experiments demonstrate that the SC method can effectively recognize similar signals compared to the conventional normalized cross-correlation coefficient (NCC) under high background noise conditions. The SC presents good robustness in identifying similar signals and performs well in the case of an extremely low signal-to-noise ratio (SNR), which makes it suitable for detecting weak seismic signals concealed by noise. As a real application case, we use the SC method to detect quasi-Love (QL) surface waves. QL waves are scattered Love waves and are important indicators for lateral anisotropic gradients in the upper mantle. We detect the QL waves at 21 stations deployed across Japan after the 23 December 2004 Mw 8.1 Macquarie earthquake by using the SC method. Obvious QL waves are observed at 19 stations, and we locate the Love-to-Rayleigh scatterers by applying the delay times between the QL and main Love waves. Our results show that the QL wave scatterers were mostly generated in two areas: Mariana subduction and Papua New Guinea. The observations of QL waves suggest the presence of lateral gradients in anisotropy beneath those two areas. The spatial distribution of the 13 scatterers in the Mariana subduction zone agrees well with the Mariana Island Arc, and we infer that the Mariana slab may have melted and coupled with the surrounding mantle at depth.
Effect of a church-based intervention on abstinence communication among African-American caregiver–child dyads: the role of gender of caregiver and child
Authors: Cederbaum Julie A , Kim Soojong , Zhang Jingwen , Jemmott John B , Jemmott Loretta S
Published: February 2021

Parent–child sexual-health communication is critical. Religious involvement is important in many African-American families, but can be a barrier to sexual-health communication. We tested a theory-based, culturally tailored intervention to increase sexual-abstinence communication among church-attending African-American parent–child dyads. In a randomized controlled trial, 613 parent–child dyads were randomly assigned to one of three 3-session interventions: (i) faith-based abstinence-only; (ii) non-faith-based abstinence-only; or (iii) attention-matched health-promotion control. Data were collected pre- and post-intervention, and 3-, 6-, 12- and 18-months post-intervention. Generalized-estimating-equations Poisson-regression models revealed no differences in communication by intervention arm. However, three-way condition � sex-of-child � sex-of-parent interactions on children’s reports of parent–child communication about puberty [IRR=0.065, 95% CI: (0.010, 0.414)], menstruation or wet dreams [IRR=0.103, 95% CI: (0.013, 0.825)] and dating [IRR=0.102, 95% CI: (0.016, 0.668)] indicated that the non-faith-based abstinence intervention’s effect on increasing communication was greater with daughters than with sons, when the parent was the father. This study highlights the importance of considering parent and child gender in the efficacy of parent–child interventions and the need to tailor interventions to increase fathers’ comfort with communication.
The pathogenic m.8993 T > G mutation in mitochondrial ATP6 gene prevents proton release from the subunit c-ring rotor of ATP synthase
Authors: Su Xin , Dautant Alain , Rak Malgorzata , Godard François , Ezkurdia Nahia , Bouhier Marine , Bietenhader Maïlis , Mueller David M , Kucharczyk Roza , di Rago Jean-Paul , Tribouillard-Tanvier Déborah
Published: February 2021

The human ATP synthase is an assembly of 29 subunits of 18 different types, of which only two (a and 8) are encoded in the mitochondrial genome. Subunit a, together with an oligomeric ring of c-subunit (c-ring), forms the proton pathway responsible for the transport of protons through the mitochondrial inner membrane, coupled to rotation of the c-ring and ATP synthesis. Neuromuscular diseases have been associated to a number of mutations in the gene encoding subunit a, ATP6. The most common, m.8993 T > G, leads to replacement of a strictly conserved leucine residue with arginine (aL156R). We previously showed that the equivalent mutation (aL173R) dramatically compromises respiratory growth of Saccharomyces cerevisiae and causes a 90% drop in the rate of mitochondrial ATP synthesis. Here, we isolated revertants from the aL173R strain that show improved respiratory growth. Four first-site reversions at codon 173 (aL173M, aL173S, aL173K and aL173W) and five second-site reversions at another codon (aR169M, aR169S, aA170P, aA170G and aI216S) were identified. Based on the atomic structures of yeast ATP synthase and the biochemical properties of the revertant strains, we propose that the aL173R mutation is responsible for unfavorable electrostatic interactions that prevent the release of protons from the c-ring into a channel from which protons move from the c-ring to the mitochondrial matrix. The results provide further evidence that yeast aL173 (and thus human aL156) optimizes the exit of protons from ATP synthase, but is not essential despite its strict evolutionary conservation.
Spectral Theory of Schrödinger Operators over Circle Diffeomorphisms
Authors: Jitomirskaya Svetlana , Kocić Saša
Published: February 2021

We initiate the study of Schrödinger operators with ergodic potentials defined over circle map dynamics, in particular over circle diffeomorphisms. For analytic circle diffeomorphisms and a set of rotation numbers satisfying Yoccoz’s ${{\mathcal{H}}}$ arithmetic condition, we discuss an extension of Avila’s global theory. We also give an abstract version and a short proof of a sharp Gordon-type theorem on the absence of eigenvalues for general potentials with repetitions. Coupled with the dynamical analysis, we obtain that, for every $C^{1+BV}$ circle diffeomorphism, with a super Liouville rotation number and an invariant measure $\mu $, and for $\mu $-almost all $x\in{{\mathbb{T}}}^1$, the corresponding Schrödinger operator has purely continuous spectrum for every Hölder continuous potential $V$.
Mitigating imperfect data validity in administrative data PSIs: a method for estimating true adverse event rates
Authors: Boussat Bastien , Quan Hude , Labarere Jose , Southern Danielle , Couris Chantal M , Ghali William A
Published: February 2021

Question

Are there ways to mitigate the challenges associated with imperfect data validity in Patient Safety Indicator (PSI) report cards?

Findings

Applying a methodological framework on simulated PSI report card data, we compare the adjusted PSI rates of three hospitals with variable quality of data and coding. This framework combines (i) a measure of PSI rates using existing algorithms; (ii) a medical record review on a small random sample of charts to produce a measure of hospital-specific data validity and (iii) a simple Bayesian calculation to derive estimated true PSI rates. For example, the estimated true PSI rate, for a theoretical hospital with a moderately good quality of coding, could be three times as high as the measured rate (for example, 1.4% rather than 0.5%). For a theoretical hospital with relatively poor quality of coding, the difference could be 50-fold (for example, 5.0% rather than 0.1%).

Meaning

Combining a medical chart review on a limited number of medical charts at the hospital level creates an approach to producing health system report cards with estimates of true hospital-level adverse event rates.
AUCs and 123s: a critical appraisal of vancomycin therapeutic drug monitoring in paediatrics
Authors: Jorgensen Sarah C. J. , Dersch-Mills Deonne , Timberlake Kathryn , Stewart Jackson J. , Gin Alfred , Dresser Linda D. , Dalton Bruce R.
Published: February 2021

The revised vancomycin guidelines recommend implementing AUC24-based therapeutic drug monitoring (TDM) using Bayesian methods in both adults and paediatrics. The motivation for this change was accumulating evidence showing aggressive dosing to achieve high troughs, as recommended in the first guidelines for adults and extrapolated to paediatrics, is associated with increased nephrotoxicity without improving clinical outcomes. AUC24-based TDM requires substantial resources that may need to be diverted from other valuable interventions. It can therefore be justified only after certain assumptions are shown to be true: (i) there is a clear relationship between vancomycin efficacy and/or toxicity and the proposed therapeutic range; and (ii) maintaining exposure within the target range with AUC24-based TDM improves clinical outcomes and/or decreases toxicity. In this review, we critically appraise the scientific basis for these assumptions. We find studies evaluating the relationship between vancomycin AUC24/MIC and efficacy in adults and children do not offer strong support for the recommended lower limit of the proposed therapeutic range (i.e. AUC24/MIC ≥400). Nephrotoxicity in children increases in a stepwise manner along the vancomycin exposure continuum but it is unclear if one parameter (AUC24 versus trough) is a superior predictor. Overall, evidence in children suggests good-to-excellent correlation between AUC24 and trough. Most importantly, there is no convincing evidence that the method of vancomycin TDM has a causal role in improving efficacy or reducing toxicity. These findings question the need to transition to resource-intensive AUC24-based TDM over retaining trough-based TDM with lower targets to minimize nephrotoxicity in paediatrics.
Complete Fusion of Both Eyelids in Stevens-Johnson Syndrome: Case Report
Authors: Santamaria Joseph A , Cancio Leopoldo C , Reed Donovan , Phillips Hunter , Chen Sien , Carlton Darrel K , Johnson Anthony J
Published: February 2021

An 18-year-old woman developed Stevens-Johnson syndrome (SJS) with ocular involvement after taking ibuprofen. She was admitted to another hospital, received saline flushes and bacitracin ophthalmic ointment to the eyes, and became unable to open them. Upon transfer to this burn center 3 weeks after symptom onset, there was complete fusion of both eyelids with no visible cornea or sclera. She underwent bilateral operative scar release. After opening the lids, meticulous debridement of cicatricial membranes and release of symblephara were performed with subsequent placement of amniotic membrane grafts. Her vision slowly improved, though her long-term visual prognosis remains guarded. Early recognition and treatment of SJS or toxic epidermal necrolysis (TEN) with ocular involvement is imperative. Even mild cases may require intensive topical lubrication, steroids, and antibiotics, with early placement of amniotic membrane grafts in severe cases. Prompt intervention and daily evaluation are paramount in preventing lifelong visual disability.
Historical Origins of the Personal Belief Exemption to Vaccination Mandates: The View from California
Authors: Conis Elena , Kuo Jonathan
Published: February 2021

A number of states, starting with California, have recently removed all non-medical exemptions from their laws requiring vaccinations for schoolchildren. California was also one of the earliest states to include a broad non-medical, or personal, belief exemption in its modern immunization law, which it did with a 1961 law mandating polio vaccination for school enrollment, Assembly Bill 1940 (AB 1940). This paper examines the history of AB 1940’s exemption clause as a case study for shedding light on the little-examined history of the personal belief exemption to vaccination in the United States. This history shows that secular belief exemptions date back further than scholars have allowed. It demonstrates that such exemptions resulted from political negotiation critical to ensuring compulsory vaccination’s political success. It challenges a historiography in which antivaccination groups and their allies led late-nineteenth and early-twentieth century opposition to vaccination mandates while religious groups drove mid-twentieth century opposition. It also complicates the historiographic idea of a return to compulsion in the late 1960s, instead dating this return a decade earlier, to a time when belief exemptions in polio vaccination mandates helped reconcile the goal of a widely vaccinated population with the sacrosanct idea of health as a personal responsibility.
Progress in heterologous biosynthesis of forskolin
Authors: Ju Haiyan , Zhang Chuanbo , Lu Wenyu
Published: February 2021

Forskolin, a class of labdane-type diterpenoid, has significant medicinal value in anticancer, antiasthmatic, antihypertensive, and heart-strengthening treatments. The main source of natural forskolin is its extraction from the cork tissue of the root of Coleus forskohlii. However, conventional modes of extraction pose several challenges. In recent years, the construction of microbial cell factories to produce medicinal natural products via synthetic biological methods has effectively solved the current problems and is a research hotspot in this field. This review summarizes the recent progress in the heterologous synthesis of forskolin via synthetic biological technology, analyzes the current challenges, and proposes corresponding strategies.
Lumbar and sacral brucellosis due to queso fresco ingestion
Authors: Krause Cassandra , Chang Michael , Veltman Jennifer , Luo-Owen Xian , Kim Esther , Danisa Olumide , Abou-Zamzam Ahmed M , Mukherjee Kaushik
Published: February 2021

Brucellosis is rare in the USA, with 100–200 cases reported annually. In this case we illustrate the complex management of spinal brucellosis. A 22-year-old male presented with 3 months of low back pain. Imaging revealed osteomyelitis/diskitis of L5/S1 and abscesses involving the pre-vertebral, epidural and pelvic recesses. Initial biopsies were inconclusive, but the patient later endorsed eating unpasteurized cheese (queso fresco) from Mexico; therefore, Brucella serology was sent and was positive. Despite aggressive antibiotic therapy there was disease progression. The patient underwent debridement of the involved vertebrae and drainage. Multiple cultures failed to grow the organisms, but Brucella polymerase chain reaction was positive. A month later he underwent a second vertebral debridement as well as placement of tobramycin impregnated beads in the vertebral space. He has since recovered. Surgery should be considered if there is a poor response to medical management and patients may need repeated debridement.
Bilateral delayed traumatic diaphragmatic injury
Authors: Sauer Durand Anna M , Nebiker Christian A , Hartel Mark , Kremer Michael
Published: February 2021

A 47-year-old patient presented at our emergency department with acute epigastric pain. A thoracic X-ray showed a partially intrathoracic stomach as well as bowel left sided. A following computed tomography scan diagnosed a diaphragmatic hernia. In the patient’s history, 20 years ago a serious car accident was reported as the presumable traumatic origin. Intraoperatively, the diaphragmatic hernia was repaired with a direct suture and mesh augmentation. The rest of the abdomen was clear. In a thoracic X-ray following chest tube removal, herniated small bowel appeared intrathoracally on the right. Relaparotomy showed an extensive diaphragmatic hernia with parts of the liver, small bowel and colon in the right thoracic cavity. Only a partial direct repair was possible, an inlay mesh repair was performed. The further recovery was uneventful.

Bilateral delayed traumatic diaphragmatic hernias are extremely rare, but with a suggestive trauma history thorough intraoperative exploration of the contralateral side should be evaluated.
Coronary artery aneurysm complicated by pneumothorax with a history of Kawasaki disease
Authors: Ishida Shinichi , Mutsuga Masato , Fujita Takashi , Ito Masao , Okamoto Sawako , Yagami Kei
Published: February 2021

Kawasaki disease (KD) is a common vasculitis disorder of childhood. It can sometimes complicate coronary artery aneurysms, and treatment is required depending on the condition of stenosis. A 20-year-old man was referred for surgery with a coronary artery aneurysm and stenosis in the left coronary artery as sequelae of KD. He had a surgical history of left pneumothorax and bullae remaining on the right lung. We simultaneously performed off-pump coronary artery bypass for coronary artery stenosis and bullectomy. Coronary artery aneurysms with KD complicated by pneumothorax are rare, and we treated them using one-stage surgery.
Enteric fever and COVID-19 co-infection in a teenager returning from Pakistan
Authors: Ayoubzadeh Sasha I , Isabel Sandra , Coomes Eric A , Morris Shaun K
Published: February 2021

As severe acute respiratory syndrome coronavirus 2 has become widespread around the globe, co-infection with other endemic infectious diseases will occur. Here we present the first reported case of enteric fever and coronavirus disease 2019 co-infection, in a teenager returning from travel to Pakistan and describe his clinical course.
Discovery of five new Galactic symbiotic stars in the VPHAS+ survey
Authors: Akras Stavros , Gonçalves Denise R , Alvarez-Candal Alvaro , Pereira Claudio B
Published: February 2021

We report the validation of a recently proposed infrared (IR) selection criterion for symbiotic stars (SySts). Spectroscopic data were obtained for seven candidates, selected from the SySt candidates of Akras et al. by employing the new supplementary IR selection criterion for SySts in the VST/OmegaCAM Photometric H-Alpha Survey. Five of them turned out to be genuine SySts after the detection of H α, He ii, and [O iii] emission lines as well as TiO molecular bands. The characteristic O vi Raman-scattered line is also detected in one of these SySts. According to their IR colours and optical spectra, all five newly discovered SySts are classified as S-type. The high rate of true SySts detections of this work demonstrates that the combination of the H α emission and the new IR criterion improves the selection of target lists for follow-up observations by minimizing the number of contaminants and optimizing the observing time.
Dispersion measure distributions of fast radio bursts due to the intergalactic medium
Authors: Medlock Isabel , Cen Renyue
Published: February 2021

Utilizing cosmological hydrodynamic simulations, we quantify the distributions of the dispersion measure (DM) of fast radio bursts (FRBs). We examine the contributions of cold, warm-hot, and hot gas to the total DM. We find that the hot gas component (T > 107K), on average, makes a minor contribution ($\le 5{{\ \rm per\ cent}}$) to the overall DM. Cold (T < 105K) and warm-hot (T = 105 − 107K) gas components make comparable contributions to DM for FRBs at z = 1, with the former component making an increasingly larger contribution towards higher redshift. We provide a detailed DM distribution of FRBs at z = 0.25 to z = 2 that may be compared to observations. We also compute the relation between the Compton y parameter and DM, finding a strong correlation, y∝DM4, providing an additional, independent constraint on the nature of the DM of FRBs.
Formation and evolution of protostellar accretion discs – I. Angular-momentum budget, gravitational self-regulation, and numerical convergence
Authors: Xu Wenrui , Kunz Matthew W
Published: February 2021

We investigate the formation and early evolution of a protostellar disc from a magnetized prestellar core using non-ideal magnetohydrodynamic (MHD) simulations including ambipolar diffusion and Ohmic dissipation. The dynamical contraction of the prestellar core ultimately leads to the formation of a first hydrostatic core, after ambipolar diffusion decouples the magnetic field from the predominantly neutral gas. The hydrostatic core accumulates angular momentum from the infalling material, evolving into a rotationally supported torus; this ‘first hydrostatic torus’ then forms an accreting protostar and a rotationally supported disc. The disc spreads out by gravitational instability, reaching ∼30 au in diameter at ∼3 kyr after protostar formation. The total mass and angular momentum of the protostar–disc system are determined mainly by accretion of gas from an infalling pseudo-disc, which has low specific angular momentum because of magnetic braking; their removal from the protostar–disc system by outflow and disc magnetic braking are negligible, in part because the magnetic field is poorly coupled there. The redistribution of angular momentum within the protostar–disc system is facilitated mainly by gravitational instability; this allows formation of relatively large discs even when the specific angular momentum of infalling material is low. We argue that such discs should remain marginally unstable as they grow (with Toomre Q ∼ 1–2), an idea that is broadly consistent with recent observational estimates for Class 0/I discs. We discuss the numerical convergence of our results, and show that properly treating the inner boundary condition is crucial for achieving convergence at an acceptable computational cost.
Quantiles as robust probes of non-Gaussianity in 21-cm images
Authors: Banet Alon , Barkana Rennan , Fialkov Anastasia , Guttman Or
Published: February 2021

The epoch in which the first stars and galaxies formed is among the most exciting unexplored eras of the Universe. A major research effort is focused on probing this era with the 21-cm spectral line of hydrogen. While most research works focus on statistics like the 21-cm power spectrum or the sky-averaged global signal, there are other ways to analyse tomographic 21-cm maps, which may lead to novel insights. We suggest statistics based on quantiles as a method to probe non-Gaussianities of the 21-cm signal. We show that they can be used in particular to probe the variance, skewness, and kurtosis of the temperature distribution, but are more flexible and robust than these standard statistics. We test these statistics on a range of possible astrophysical models, including different galactic halo masses, star formation efficiencies, and spectra of the X-ray heating sources, plus an exotic model with an excess early radio background. Simulating data with angular resolution and thermal noise as expected for the Square Kilometre Array (SKA), we conclude that these statistics can be measured out to redshifts above 20 and offer a promising statistical method for probing early cosmic history.
Informative Bayesian model selection for RR Lyrae star classifiers
Authors: Pérez-Galarce F , Pichara K , Huijse P , Catelan M , Mery D
Published: February 2021

Machine learning has achieved an important role in the automatic classification of variable stars, and several classifiers have been proposed over the last decade. These classifiers have achieved impressive performance in several astronomical catalogues. However, some scientific articles have also shown that the training data therein contain multiple sources of bias. Hence, the performance of those classifiers on objects not belonging to the training data is uncertain, potentially resulting in the selection of incorrect models. Besides, it gives rise to the deployment of misleading classifiers. An example of the latter is the creation of open-source labelled catalogues with biased predictions. In this paper, we develop a method based on an informative marginal likelihood to evaluate variable star classifiers. We collect deterministic rules that are based on physical descriptors of RR Lyrae stars, and then, to mitigate the biases, we introduce those rules into the marginal likelihood estimation. We perform experiments with a set of Bayesian logistic regressions, which are trained to classify RR Lyraes, and we found that our method outperforms traditional non-informative cross-validation strategies, even when penalized models are assessed. Our methodology provides a more rigorous alternative to assess machine learning models using astronomical knowledge. From this approach, applications to other classes of variable stars and algorithmic improvements can be developed.
Gv1, a Zinc Finger Gene Controlling Endogenous MLV Expression
Authors: Young George R , Ferron Aaron K W , Panova Veera , Eksmond Urszula , Oliver Peter L , Kassiotis George , Stoye Jonathan P
Published: February 2021

The genomes of inbred mice harbor around 50 endogenous murine leukemia virus (MLV) loci, although the specific complement varies greatly between strains. The Gv1 locus is known to control the transcription of endogenous MLVs and to be the dominant determinant of cell-surface presentation of MLV envelope, the GIX antigen. Here, we identify a single Krüppel-associated box zinc finger protein (ZFP) gene, Zfp998, as Gv1 and show it to be necessary and sufficient to determine the GIX+ phenotype. By long-read sequencing of bacterial artificial chromosome clones from 129 mice, the prototypic GIX+ strain, we reveal the source of sufficiency and deficiency as splice-acceptor variations and highlight the varying origins of the chromosomal region encompassing Gv1. Zfp998 becomes the second identified ZFP gene responsible for epigenetic suppression of endogenous MLVs in mice and further highlights the prominent role of this gene family in control of endogenous retroviruses.
N
6-Methyladenosines in mRNAs reduce the accuracy of codon reading by transfer RNAs and peptide release factors
Authors: Ieong Ka-Weng , Indrisiunaite Gabriele , Prabhakar Arjun , Puglisi Joseph D , Ehrenberg Måns
Published: February 2021

We used quench flow to study how N6-methylated adenosines (m6A) affect the accuracy ratio between kcat/Km (i.e. association rate constant (ka) times probability (Pp) of product formation after enzyme-substrate complex formation) for cognate and near-cognate substrate for mRNA reading by tRNAs and peptide release factors 1 and 2 (RFs) during translation with purified Escherichia coli components. We estimated kcat/Km for Glu-tRNAGlu, EF-Tu and GTP forming ternary complex (T3) reading cognate (GAA and Gm6AA) or near-cognate (GAU and Gm6AU) codons. ka decreased 10-fold by m6A introduction in cognate and near-cognate cases alike, while Pp for peptidyl transfer remained unaltered in cognate but increased 10-fold in near-cognate case leading to 10-fold amino acid substitution error increase. We estimated kcat/Km for ester bond hydrolysis of P-site bound peptidyl-tRNA by RF2 reading cognate (UAA and Um6AA) and near-cognate (UAG and Um6AG) stop codons to decrease 6-fold or 3-fold by m6A introduction, respectively. This 6-fold effect on UAA reading was also observed in a single-molecule termination assay. Thus, m6A reduces both sense and stop codon reading accuracy by decreasing cognate significantly more than near-cognate kcat/Km, in contrast to most error inducing agents and mutations, which increase near-cognate at unaltered cognate kcat/Km.