bluuebunny/crossref_metadata_2025 huggingface dataset:
A new method to estimate branch biomass from terrestrial laser scanning data by bridging tree structure models
Authors: Hu Man , Pitkänen Timo P , Minunno Francesco , Tian Xianglin , Lehtonen Aleksi , Mäkelä Annikki
Published: March 2021

Background and Aims

Branch biomass and other attributes are important for estimating the carbon budget of forest stands and characterizing crown structure. As destructive measuring is time-consuming and labour-intensive, terrestrial laser scanning (TLS) as a solution has been used to estimate branch biomass quickly and non-destructively. However, branch information extraction from TLS data alone is challenging due to occlusion and other defects, especially for estimating individual branch attributes in coniferous trees.

Methods

This study presents a method, entitled TSMtls, to estimate individual branch biomass non-destructively and accurately by combining tree structure models and TLS data. The TSMtls method constructs the stem-taper curve from TLS data, then uses tree structure models to determine the number, basal area and biomass of individual branches at whorl level. We estimated the tree structural model parameters from 122 destructively measured Scots pine (Pinus sylvestris) trees and tested the method on six Scots pine trees that were first TLS-scanned and later destructively measured. Additionally, we estimated the branch biomass using other TLS-based approaches for comparison.

Key Results

Tree-level branch biomass estimates derived from TSMtls showed the best agreement with the destructive measurements [coefficient of variation of root mean square error (CV-RMSE) = 9.66 % and concordance correlation coefficient (CCC) = 0.99], outperforming the other TLS-based approaches (CV-RMSE 12.97–57.45 % and CCC 0.43–0.98 ). Whorl-level individual branch attributes estimates produced from TSMtls showed more accurate results than those produced from TLS data directly.

Conclusions

The results showed that the TSMtls method proposed in this study holds promise for extension to more species and larger areas.
Development and Psychometric Evaluation of Alternate Short Forms of the Action Naming Test
Authors: Pinto-Grau Marta , O’Connor Sarah , Murphy Lisa , Heverin Mark , Vajda Alice , Hardiman Orla , Pender Niall
Published: March 2021

Objective

The action naming test (ANT) is a confrontation naming task used to assess the ability to name action words. This study aimed to create two short forms of the ANT and assess their equivalence, reliability, and comparability to the long form.

Methods

In total, 100 healthy adults (31 females and 69 males), aged 34–89 years (M = 64 and SD = 10.4) were recruited. Short forms were developed using a split-half procedure.

Results

No significant differences were observed between short forms on mean performance and distribution of scores for correct spontaneous responses, responses after semantic cue and total correct responses after cueing, but a higher number of accurate responses were prompted after phonemic cueing for Form A. Significant strong correlations between short forms and with the full form were encountered, although a weak correlation was found between short forms on performance after semantic cueing. IQ and age were significant predictors of action word retrieval. Whereas IQ also predicted post-cueing performance in all ANT forms, age predicted performance only for Form B.

Conclusion

The two ANT short forms are equivalent when considering total spontaneous responses and total correct responses after cueing, but semantic and phonemic cues evoked different responses on the two forms. The two short forms were also affected differently by demographics. When the psychometric equivalence of Forms A and B was examined, the strict conditions for parallel forms were not met for all performance indices. Therefore, these newly developed short versions should be considered as alternate forms.
Pharmacological treatment with FGF21 strongly improves plasma cholesterol metabolism to reduce atherosclerosis
Authors: Liu Cong , Schönke Milena , Zhou Enchen , Li Zhuang , Kooijman Sander , Boon Mariëtte R , Larsson Mikael , Wallenius Kristina , Dekker Niek , Barlind Louise , Peng Xiao-Rong , Wang Yanan , Rensen Patrick C N
Published: March 2021

Aims 

Fibroblast growth factor (FGF) 21, a key regulator of energy metabolism, is currently evaluated in humans for treatment of type 2 diabetes and non-alcoholic steatohepatitis. However, the effects of FGF21 on cardiovascular benefit, particularly on lipoprotein metabolism in relation to atherogenesis, remain elusive.

Methods and results  

Here, the role of FGF21 in lipoprotein metabolism in relation to atherosclerosis development was investigated by pharmacological administration of a half-life extended recombinant FGF21 protein to hypercholesterolaemic APOE*3-Leiden.CETP mice, a well-established model mimicking atherosclerosis initiation and development in humans. FGF21 reduced plasma total cholesterol, explained by a reduction in non-HDL-cholesterol. Mechanistically, FGF21 promoted brown adipose tissue (BAT) activation and white adipose tissue (WAT) browning, thereby enhancing the selective uptake of fatty acids from triglyceride-rich lipoproteins into BAT and into browned WAT, consequently accelerating the clearance of the cholesterol-enriched remnants by the liver. In addition, FGF21 reduced body fat, ameliorated glucose tolerance and markedly reduced hepatic steatosis, related to up-regulated hepatic expression of genes involved in fatty acid oxidation and increased hepatic VLDL-triglyceride secretion. Ultimately, FGF21 largely decreased atherosclerotic lesion area, which was mainly explained by the reduction in non-HDL-cholesterol as shown by linear regression analysis, decreased lesion severity, and increased atherosclerotic plaque stability index.

Conclusion 

FGF21 improves hypercholesterolaemia by accelerating triglyceride-rich lipoprotein turnover as a result of activating BAT and browning of WAT, thereby reducing atherosclerotic lesion severity and increasing atherosclerotic lesion stability index. We have thus provided additional support for the clinical use of FGF21 in the treatment of atherosclerotic cardiovascular disease.
Effect of ovariectomy-induced osteoporosis on the amount of orthodontic tooth movement: a systematic review of animal studies
Authors: Mohammed Ayesha O , Kaklamanos Eleftherios G
Published: March 2021

Background

Understanding the impact of osteopenia and osteoporosis on orthodontic tooth movement could be of benefit to the orthodontist, but research in humans presents practical and ethical problems. The ovariectomized animal model could provide useful information on osteoporosis.

Objective

To compare the amount of tooth movement during or after the application of orthodontic forces between ovariectomized animals and control or sham-operated subjects.

Search methods

Unrestricted searches in seven databases and manual searching of the reference lists in relevant studies were performed up to February 2021 (PubMed, Central, Cochrane Database of Systematic Reviews, Scopus, Web of Science, Arab World Research Source, ProQuest Dissertations, and Theses Global).

Selection criteria

We searched for studies quantitatively comparing the amount of tooth movement during or after the application of orthodontic forces between ovariectomized animals and control or sham-operated subjects.

Data collection and analysis

Following study retrieval and selection, relevant data were extracted, and the risk of bias was assessed using the SYRCLE’s Risk of Bias Tool. Exploratory synthesis and meta-regression were carried out using the random effects model.

Results

Thirteen studies were finally selected and no specific concerns regarding bias were identified. During the active period, ovariectomy was associated with a statistically significant acceleratory effect on the rate of orthodontic tooth movement compared to non-treated rats (3 weeks; 4 studies, 0.15 mm more movement in the ovariectomized rats; 95 per cent confidence interval: 0.10–0.19; P = 0.000). Exploratory meta-regression showed that this difference could increase over time. Following force discontinuation, no statistically significant differences were observed [3 weeks; 1 study (median ± SE), Ovariectomy group: 0.30 ± 0.04 mm; Sham operation group: 0.18 ± 0.03; P = 0.1558].

Conclusions

Ovariectomy-induced osteoporosis may affect the rate of orthodontic tooth movement. Although animal studies should be approached with caution regarding their translational potential, the safe practice would suggest that one should consider potential implications.

Registration

PROSPERO (CRD42018118003).
The effect of bearing and rearing a child on blood pressure: a nationally representative instrumental variable analysis of 444 611 mothers in India
Authors: Teufel Felix , Geldsetzer Pascal , Sudharsanan Nikkil , Subramanyam Malavika , Yapa H Manisha , De Neve Jan-Walter , Vollmer, Sebastian , Bärnighausen Till
Published: March 2021

Background

At the individual level, it is well known that pregnancies have a short-term effect on a woman’s cardiovascular system and blood pressure. The long-term effect of having children on maternal blood pressure, however, is unknown. We thus estimated the causal effect of having children on blood pressure among mothers in India, a country with a history of high fertility rates.

Methods

We used nationally representative cross-sectional data from the 2015–16 India National Family and Health Survey (NFHS-4). The study population comprised 444 611 mothers aged 15–49 years. We used the sex of the first-born child as an instrumental variable (IV) for the total number of a woman’s children. We estimated the effect of an additional child on systolic and diastolic blood pressure in IV (two-stage least squares) regressions. In additional analyses, we stratified the IV regressions by time since a mother last gave birth. Furthermore, we repeated our analyses using mothers' husbands and partners as the regression sample.

Results

On average, mothers had 2.7 children [standard deviation (SD): 1.5], a systolic blood pressure of 116.4 mmHg (SD: 14.4) and diastolic blood pressure of 78.5 mmHg (SD: 9.4). One in seven mothers was hypertensive. In conventional ordinary least squares regression, each child was associated with 0.42 mmHg lower systolic [95% confidence interval (CI): –0.46 to –0.39, P < 0.001] and 0.13 mmHg lower diastolic (95% CI: –0.15 to –0.11, P < 0.001) blood pressure. In the IV regressions, each child decreased a mother’s systolic blood pressure by an average of 1.00 mmHg (95% CI: –1.26 to –0.74, P < 0.001) and diastolic blood pressure by an average of 0.35 mmHg (95% CI: –0.52 to –0.17, P < 0.001). These decreases were sustained over more than a decade after childbirth, with effect sizes slightly declining as the time since last birth increased. Having children did not influence blood pressure in men.

Conclusions

Bearing and rearing a child decreases blood pressure among mothers in India.
The time-fractional Cahn–Hilliard equation: analysis and approximation
Authors: Al-Maskari Mariam , Karaa Samir
Published: March 2021

We consider a time-fractional Cahn–Hilliard equation where the conventional first-order time derivative is replaced by a Caputo fractional derivative of order $\alpha \in (0,1)$. Based on an a priori bound of the exact solution, global existence of solutions is proved and detailed regularity results are included. A finite element method is then analyzed in a spatially discrete case and in a completely discrete case based on a convolution quadrature in time generated by the backward Euler method. Error bounds of optimal order are obtained for solutions with smooth and nonsmooth initial data, thereby extending earlier studies on the classical Cahn–Hilliard equation. Further, by proving a new result concerning the positivity of a discrete time-fractional integral operator, it is shown that the proposed numerical scheme inherits a discrete energy dissipation law at the discrete level. Numerical examples are presented to illustrate the theoretical results.
Prevention of Coronavirus Disease 2019 Among Older Adults Receiving Pneumococcal Conjugate Vaccine Suggests Interactions Between Streptococcus pneumoniae and Severe Acute Respiratory Syndrome Coronavirus 2 in the Respiratory Tract
Authors: Lewnard Joseph A , Bruxvoort Katia J , Fischer Heidi , Hong Vennis X , Grant Lindsay R , Jódar Luis , Gessner Bradford D , Tartof Sara Y
Published: March 2021

Background

While secondary pneumococcal pneumonia occurs less commonly after coronavirus disease 2019 (COVID-19) than after other viral infections, it remains unclear whether other interactions occur between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Streptococcus pneumoniae.

Methods

We probed potential interactions between these pathogens among adults aged ≥65 years by measuring associations of COVID-19 outcomes with pneumococcal vaccination (13-valent conjugate vaccine [PCV13] and 23-valent pneumococcal polysaccharide vaccine [PPSV23]). We estimated adjusted hazard ratios (aHRs) using Cox proportional hazards models with doubly robust inverse-propensity weighting. We assessed effect modification by antibiotic exposure to further test the biologic plausibility of a causal role for pneumococci.

Results

Among 531 033 adults, there were 3677 COVID-19 diagnoses, leading to 1075 hospitalizations and 334 fatalities, between 1 March and 22 July 2020. Estimated aHRs for COVID-19 diagnosis, hospitalization, and mortality associated with prior PCV13 receipt were 0.65 (95% confidence interval [CI], .59–.72), 0.68 (95% CI, .57–.83), and 0.68 (95% CI, .49–.95), respectively. Prior PPSV23 receipt was not associated with protection against the 3 outcomes. COVID-19 diagnosis was not associated with prior PCV13 within 90 days following antibiotic receipt, whereas aHR estimates were 0.65 (95% CI, .50–.84) and 0.62 (95% CI, .56–.70) during the risk periods 91–365 days and >365 days, respectively, following antibiotic receipt.

Conclusions

Reduced risk of COVID-19 among PCV13 recipients, transiently attenuated by antibiotic exposure, suggests that pneumococci may interact with SARS-CoV-2.
The case for precision dosing: medical conservatism does not justify inaction
Authors: Scheetz Marc H , Lodise Thomas P , Downes Kevin J , Drusano George , Neely Michael
Published: March 2021

The need for precision dosing has been challenged on the basis of insufficient evidence. Herein, we argue that adequate evidence exists to conduct therapeutic drug monitoring (TDM) and precisely target antibiotic exposures. While achievement of any antibiotic concentration does not guarantee efficacy sans toxicity for any single patient, stochastic control optimizes the probability of achieving favourable responses across patients. We argue that variability in targets (such as the organism’s MIC) can be considered with models. That is, complexity alone does not relegate the decision-making framework to ‘clinician intuition’. We acknowledge the exposure–response relationships are modified by patient-specific factors (other drugs, baseline organ functional status etc.) and describe how precision dosing can inform clinical decision making rather than protocolize it. Finally, we call for randomized, controlled trials; however, we suggest that these trials are not necessary to make TDM standard of care for multiple classes of antibiotics.
More from less: Genome skimming for nuclear markers for animal phylogenomics, a case study using decapod crustaceans
Authors: Tan Mun Hua , Gan Han Ming , Bracken-Grissom Heather , Chan Tin-Yam , Grandjean Frederic , Austin Christopher M
Published: March 2021

Low coverage genome sequencing is rapid and cost-effective for recovering complete mitochondrial genomes for crustacean phylogenomics. The recovery of high-copy-number nuclear genes, including histone H3, 18S and 28S ribosomal RNAs, is also possible using this approach based on our research with freshwater crayfishes (Astacidea). We explored the potential of genome skimming (GS) to recover additional nuclear genes from shallow sequencing projects using decapod crustaceans. Using an in silico-baited approach, we recovered three additional core histone genes (H2A, H2B, and H4) from our low-coverage decapod dataset (99 species, 69 genera, 38 families, 10 infraorders). Phylogenetic analyses using various combinations of mitochondrial and nuclear genes for the entire decapod dataset and a subset of 40 species of crayfishes showed that the evolutionary rates for different classes of genes varied widely. A very high level of congruence was nevertheless found between trees from the six nuclear genes and those derived from the mitogenome sequences for freshwater crayfish. These findings indicate that nuclear genes recovered from the same genome skimming datasets designed to obtain mitogenomes can be used to support more robust and comprehensive phylogenetic analyses. Further, a search for additional intron-less nuclear genes identified several high-copy-number genes across the decapod dataset, and recovery of NaK, PEPCK, and GAPDH gene fragments is possible at slightly elevated coverage, suggesting the potential and utility of GS in recovering even more nuclear genetic information for phylogenetic studies from these inexpensive and increasingly abundant datasets.
Gender Differences in Second Language Proficiency—Evidence from Recent Humanitarian Migrants in Germany
Authors: Bernhard Sarah , Bernhard Stefan
Published: March 2021

In this paper, we address gender differences in the host language proficiency of humanitarian migrants. Prior research has produced inconclusive results with regard to women’s host language proficiency relative to that of men: sometimes women’s proficiency exceeds that of men, sometimes women lag behind men, and sometimes there are no substantial differences. Using data on recent humanitarian migrants in Germany, we investigate factors contributing to similarities and differences in men’s and women’s language proficiency. We consider gender differences with respect to the family-related factors: marital status, children’s ages and children’s childcare situations are important for women but not for men. These findings point to the continued relevance of a gendered division of work. It also becomes clear that gendered role expectations are particularly consequential for mothers and wives. Moreover, we find evidence that women are more efficient learners than men are, while they have fewer learning opportunities than men.
A Dynamic Survival Modeling Approach to the Prediction of Web Survey Breakoff
Authors: Mittereder Felicitas , West Brady T
Published: March 2021

Respondents who break off from a web survey prior to completing it are a prevalent problem in data collection. To prevent breakoff bias, it is crucial to keep as many diverse respondents in a web survey as possible. As a first step of preventing breakoffs, this study aims to understand breakoff and the associated response behavior. We analyze data from an annual online survey using dynamic survival models and ROC analyses. We find that breakoff risks between respondents using mobile devices versus PCs do not differ at the beginning of the questionnaire, but the risk for mobile device users increases as the survey progresses. Very fast respondents as well as respondents with changing response times both have a higher risk of quitting the questionnaire, compared to respondents with slower and steady response times. We conclude with a discussion of the implications of these findings for future practice and research in web survey methodology.
Genome-wide association study and transcriptome comparison reveal novel QTL and candidate genes that control petal size in rapeseed
Authors: Qian Mingchao , Fan Yonghai , Li Yanhua , Liu Miao , Sun Wei , Duan Huichun , Yu Mengna , Chang Wei , Niu Yue , Li Xiaodong , Liang Ying , Qu Cunmin , Li Jiana , Lu Kun
Published: March 2021

Petal size determines the value of ornamental plants, and thus their economic value. However, the molecular mechanisms controlling petal size remain unclear in most non-model species. To identify quantitative trait loci and candidate genes controlling petal size in rapeseed (Brassica napus), we performed a genome-wide association study (GWAS) using data from 588 accessions over three consecutive years. We detected 16 signiﬁcant single nucleotide polymorphisms (SNPs) associated with petal size, with the most significant SNPs located on chromosomes A05 and C06. A combination of GWAS and transcriptomic sequencing based on two accessions with contrasting differences in petal size identified 52 differentially expressed genes (DEGs) that may control petal size variation in rapeseed. In particular, the rapeseed gene BnaA05.RAP2.2, homologous to Arabidopsis RAP2.2, may be critical to the negative control of petal size through the ethylene signaling pathway. In addition, a comparison of petal epidermal cells indicated that petal size differences between the two contrasting accessions were determined mainly by differences in cell number. Finally, we propose a model for the control of petal size in rapeseed through ethylene and cytokinin signaling pathways. Our results provide insights into the genetic mechanisms regulating petal size in flowering plants.
Information entropy in cosmological inference problems
Authors: Pinho Ana Marta , Reischke Robert , Teich Marie , Schäfer Björn Malte
Published: March 2021

The subject of this paper is a quantification of the information content of cosmological probes of the large-scale structures, specifically of temperature and polarization anisotropies in the cosmic microwave background (CMB), CMB-lensing, weak cosmic shear and galaxy clustering, in terms of information theory measures like entropies. We aim to establish relationships between conventional measures of statistical uncertainties and information entropies for Gaussian likelihoods, which are described by the Fisher-formalism. Furthermore, we extend these studies to the computation of (Bayesian) evidences and the power of measurement to distinguish between competing models. We investigate in detail how cosmological data decrease information entropy by reducing statistical errors and by breaking degeneracies. In addition, we work out how tensions between data sets increase information entropy and quantify this effect in three examples: the discrepancy in Ωm and σ8 between the CMB and weak lensing, the role of intrinsic alignments in weak lensing data when attempting the dark energy equation of state parameters, and the famous H0-tension between Cepheids in the Hubble keystone project and the CMB as observed by Planck.
Towards a larger sample of radio jets from quiescent black hole X-ray binaries
Authors: Plotkin R M , Bahramian A , Miller-Jones J C A , Reynolds M T , Atri P , Maccarone T J , Shaw A W , Gandhi P
Published: March 2021

Quiescent black hole X-ray binaries (X-ray luminosities ${\lesssim} 10^{34}\,{\rm erg}\, {\rm s}^{-1}$) are believed to be fed by hot accretion flows that launch compact, relativistic jets. However, due to their low luminosities, quiescent jets have been detected in the radio waveband from only five systems so far. Here, we present radio observations of two quiescent black hole X-ray binaries with the Australia Telescope Compact Array. One system, GS 1124-684, was not detected. The other system, BW Cir, was detected over two different epochs in 2018 and 2020, for which we also obtained quasi-simultaneous X-ray detections with Chandra and Swift. BW Cir is now the sixth quiescent X-ray binary with a confirmed radio jet. However, the distance to BW Cir is uncertain, and we find that BW Cir shows different behaviour in the radio/X-ray luminosity plane depending on the correct distance. Estimates based on its G-type subgiant donor star place BW Cir at >25 kpc, while initial optical astrometric measurements from Gaia Data Release 2 suggested likely distances of just a few kpc. Here, we use the most recent measurements from Gaia Early Data Release 3 and find a distance $d=7.1^{+4.8}_{-3.9}$ kpc and a potential kick velocity PKV = $165^{+81}_{-17}$ km s−1, with distances up to ≈20 kpc possible based on its parallax and proper motion. Even though there is now less tension between the parallax and donor-star based distance measurements, it remains an unresolved matter, and we conclude with suggestions on how to reconcile the two measurements.
Implications of an improved water equation of state for water-rich planets
Authors: Huang(黄辰亮) Chenliang , Rice David R , Grande Zachary M , Smith Dean , Smith Jesse S , Boisvert John H , Tschauner Oliver , Salamat Ashkan , Steffen Jason H
Published: March 2021

Water (H2O), in all forms, is an important constituent in planetary bodies, controlling habitability and influencing geological activity. Under conditions found in the interior of many planets, as the pressure increases, the H-bonds in water gradually weaken and are replaced by ionic bonds. Recent experimental measurements of the water equation of state (EOS) showed both a new phase of H-bonded water ice, ice-VIIt, and a relatively low transition pressure just above 30 GPa to ionic bonded ice-X, which has a bulk modulus 2.5 times larger. The higher bulk modulus of ice-X produces larger planets for a given mass, thereby either reducing the atmospheric contribution to the volume of many exoplanets or limiting their water content. We investigate the impact of the new EOS measurements on the planetary mass–radius relation and interior structure for water-rich planets. We find that the change in the planet mass–radius relation caused by the systematic differences between previous and new experimental EOS measurements is comparable to the observational uncertainties in some planet sizes – an issue that will become more important as observations continue to improve.
A unified calibration framework for 21 cm cosmology
Authors: Byrne Ruby , Morales Miguel F , Hazelton Bryna J , Wilensky Michael
Published: March 2021

Calibration precision is currently a limiting systematic in 21 cm cosmology experiments. While there are innumerable calibration approaches, most can be categorized as either ‘sky-based,’ relying on an extremely accurate model of astronomical foreground emission, or ‘redundant,’ requiring a precisely regular array with near-identical antenna response patterns. Both of these classes of calibration are inflexible to the realities of interferometric measurement. In practice, errors in the foreground model, antenna position offsets, and beam response inhomogeneities degrade calibration performance and contaminate the cosmological signal. Here, we show that sky-based and redundant calibration can be unified into a highly general and physically motivated calibration framework based on a Bayesian statistical formalism. Our new framework includes sky-based and redundant calibration as special cases but can additionally support relaxing the rigid assumptions implicit in those approaches. We present simulation results demonstrating that, in a simple case, working in an intermediate regime between sky-based and redundant calibration improves calibration performance. Our framework is highly general and encompasses novel calibration approaches including techniques for calibrating compact non-redundant arrays, calibrating to incomplete sky models, and constraining calibration solutions across frequency.
On the alignment of haloes, filaments and magnetic fields in the simulated cosmic web
Authors: Banfi S , Vazza F , Gheller C
Published: March 2021

The continuous flow of gas and dark matter across scales in the cosmic web can generate correlated dynamical properties of haloes and filaments (and the magnetic fields they contain). With this work, we study the halo spin properties and orientation with respect to filaments, and the morphology of the magnetic field around these objects, for haloes with masses in the range ∼108–1014 M⊙ and filaments up to ∼8 Mpc long. Furthermore, we study how these properties vary in presence, or lack thereof, of different (astro)physical processes and with different magnetic initial conditions. We perform cosmological magnetohydrodynamical simulations with the Eulerian code Enzo and we develop a simple and robust algorithm to study the filamentary connectivity of haloes in three dimensions. We investigate the morphological and magnetic properties and focus on the alignment of the magnetic field along filaments: our analysis suggests that the degree of this alignment is partially dependent on the physical processes involved, as well as on magnetic initial conditions. We discuss the contribution of this effect on a potential attempt to detect the magnetic field surrounding these objects: we find that it introduces a bias in the estimation of the magnetic field from Faraday rotation measure techniques. Specifically, given the strong tendency we find for extragalactic magnetic fields to align with the filaments axis, the value of the magnetic field can be underestimated by a factor ∼3, because this effect contributes to making the line-of-sight magnetic field (for filaments in the plane of the sky) much smaller than the total one.
Constraining neutron star radii in black hole–neutron star mergers from their electromagnetic counterparts
Authors: Fragione Giacomo , Loeb Abraham
Published: March 2021

Mergers of black hole (BH) and neutron star (NS) binaries are of interest since the emission of gravitational waves (GWs) can be followed by an electromagnetic (EM) counterpart, which could power short gamma-ray bursts. Until now, LIGO/Virgo has only observed a candidate BH–NS event, GW190426_152155, which was not followed by any EM counterpart. We discuss how the presence (absence) of a remnant disc, which powers the EM counterpart, can be used along with spin measurements by LIGO/Virgo to derive a lower (upper) limit on the radius of the NS. For the case of GW190426_152155, large measurement errors on the spin and mass ratio prevent from placing an upper limit on the NS radius. Our proposed method works best when the aligned component of the BH spin (with respect to the orbital angular momentum) is the largest, and can be used to complement the information that can be extracted from the GW signal to derive valuable information on the NS equation of state.
On the zero point constant of the bolometric correction scale
Authors: Eker Z , Bakış V , Soydugan F , Bilir S
Published: March 2021

Arbitrariness attributed to the zero-point constant of the V-band bolometric corrections (BCV) and its relation to ‘bolometric magnitude of a star ought to be brighter than its visual magnitude’ and ‘bolometric corrections must always be negative’ was investigated. The falsehood of the second assertion became noticeable to us after IAU 2015 General Assembly Resolution B2, where the zero-point constant of bolometric magnitude scale was decided to have a definite value CBol(W) = 71.197 425 ... . Since the zero-point constant of the BCV scale could be written as C2 = CBol − CV, where CV is the zero-point constant of the visual magnitudes in the basic definition BCV = MBol − MV = mbol − mV, and CBol > CV, the zero-point constant (C2) of the BCV scale cannot be arbitrary anymore; rather, it must be a definite positive number obtained from the two definite positive numbers. The two conditions C2 > 0 and 0 < BCV < C2 are also sufficient for LV < L, a similar case to negative BCV numbers, which means that ‘bolometric corrections are not always negative’. In sum it becomes apparent that the first assertion is misleading causing one to understand bolometric corrections must always be negative, which is not necessarily true.
Revisiting the Kepler field with TESS: Improved ephemerides using TESS 2 min data
Authors: Battley Matthew P , Kunimoto Michelle , Armstrong David J , Pollacco Don
Published: March 2021

Up to date planet ephemerides are becoming increasingly important as exoplanet science moves from detecting exoplanets to characterizing their architectures and atmospheres in depth. In this work, ephemerides are updated for 22 Kepler planets and 4 Kepler planet candidates, constituting all Kepler planets and candidates with sufficient signal to noise in the TESS 2 min data set. A purely photometric method is utilized here to allow ephemeris updates for planets even when they do not posses significant radial velocity data. The obtained ephemerides are of very high precision and at least seven years ‘fresher’ than archival ephemerides. In particular, significantly reduced period uncertainties for Kepler-411d, Kepler-538b, and the candidates K00075.01/K00076.01 are reported. O–C diagrams were generated for all objects, with the most interesting ones discussed here. Updated TTV fits of five known multiplanet systems with significant TTVs were also attempted (Kepler-18, Kepler-25, Kepler-51, Kepler-89, and Kepler-396), however these suffered from the comparative scarcity and dimness of these systems in TESS. Despite these difficulties, TESS has once again shown itself to be an incredibly powerful follow-up instrument as well as a planet-finder in its own right. Extension of the methods used in this paper to the 30 min-cadence TESS data and TESS extended mission has the potential to yield updated ephemerides of hundreds more systems in the future.
Genetic and epigenetic changes in the eutopic endometrium of women with endometriosis: association with decreased endometrial αvβ3 integrin expression
Authors: Joshi Niraj R , Kohan-Ghadr Hamid-Reza , Roqueiro Damian S , Yoo Jung Yoon , Fru Karenne , Hestermann Eli , Yuan Lingwen , Ho Shuk-Mei , Jeong Jae-Wook , Young Steven L , Lessey Bruce A , Fazleabas Asgerally T
Published: March 2021

About 40% of women with infertility and 70% of women with pelvic pain suffer from endometriosis. The pregnancy rate in women undergoing IVF with low endometrial integrin αvβ3 (LEI) expression is significantly lower compared to the women with high endometrial integrin αvβ3 (HEI). Mid-secretory eutopic endometrial biopsies were obtained from healthy controls (C; n=3), and women with HEI (n=4) and LEI (n=4) and endometriosis. Changes in gene expression were assessed using human gene arrays and DNA methylation data were derived using 385 K Two-Array Promoter Arrays. Transcriptional analysis revealed that LEI and C groups clustered separately with 396 differentially expressed genes (DEGs) (P<0.01: 275 up and 121 down) demonstrating that transcriptional and epigenetic changes are distinct in the LEI eutopic endometrium compared to the C and HEI group. In contrast, HEI vs C and HEI vs LEI comparisons only identified 83 and 45 DEGs, respectively. The methylation promoter array identified 1304 differentially methylated regions in the LEI vs C comparison. The overlap of gene and methylation array data identified 14 epigenetically dysregulated genes and quantitative RT–PCR analysis validated the transcriptomic findings. The analysis also revealed that aryl hydrocarbon receptor (AHR) was hypomethylated and significantly overexpressed in LEI samples compared to C. Further analysis validated that AHR transcript and protein expression are significantly (P<0.05) increased in LEI women compared to C. The increase in AHR, together with the altered methylation status of the 14 additional genes, may provide a diagnostic tool to identify the subset of women who have endometriosis-associated infertility.
Origin and Use of Hydrogen Peroxide in Neurosurgery
Authors: Bailey David , Rizk Elias B
Published: March 2021

Hydrogen peroxide (H2O2) is a chemical with a wide range of applications. This includes its use in the medical field, in which its use has been ubiquitous but is most useful as an antiseptic and in achieving hemostasis. Neurosurgeons have been using H2O2 for well over a century, primarily for its hemostatic and antiseptic effects. This is in spite of the fact that the actual effectiveness of H2O2 as an antiseptic is questionable, and its use, in general, may be more dangerous than it appears. We review the application of H2O2 in medicine generally and, more specifically, in neurosurgery. This review outlines the reasoning behind the use of H2O2 as an antiseptic and details why it may not be as effective as one might think. We also detail its use as a hemostatic agent in neurosurgery, reviewing a number of techniques in which it has been useful in this role. Finally, we review the documented cases of complications associated with the use of H2O2 in neurosurgery. Ultimately, we conclude that the use of H2O2 in neurosurgery be reconsidered because of its lack of effectiveness as an antiseptic and potentially fatal complications.
Diagnosing axial spondyloarthritis: estimation of the disease probability in patients witha prioridifferent likelihoods of the diagnosis
Authors: Poddubnyy Denis , Proft Fabian , Spiller Laura , Protopopov Mikhail , Rios Rodriguez Valeria , Muche Burkhard , Rademacher Judith , Torgutalp Murat , Vahldiek Janis Lucas , Sieper Joachim , Redeker Imke
Published: March 2021

Objective

To evaluate the diagnostic value of SpA parameters and their combination for the diagnosis of axial SpA in patients with an a priori different probability of the diagnosis.

Methods

A total of 361 patients with chronic back pain and suspicion of axial SpA (181 referred by primary care physicians or orthopaedists, 180 recruited via an online screening tool) received a structured rheumatologic examination, which resulted into a diagnosis or exclusion of axial SpA. The prevalence of axial SpA indicating the pre-test probability was 40% in the physician-referred subgroup and 20% in the online screening subgroup. Sensitivities, specificities and likelihood ratios for SpA features were determined in both subgroups and the respective post-test probabilities of axial SpA were calculated.

Results

The relative diagnostic value of single SpA features varied substantially between the groups with different referral pathways. For instance, HLA-B27 positivity increased the probability of the presence of axial SpA by 35% to 55% in online-screened patients and by 22% to 62% in physician-referred patients. The absence of HLA-B27 resulted in a sharp decrease in the probability of the presence of axial SpA in physician-referred patients (from 40% to 6%). This decrease was less sharp in the online screening group (from 20% to 10%). These differences were especially relevant in patients with a small number (one to two) of positive SpA features.

Conclusion

The diagnostic value of SpA features varies in different patient populations, which should be considered in the diagnostic approach.
Secular trends of grossly underreported snakebite burden in India, 2009–2018: analysis of data from India's National Health Profile
Authors: Rubeshkumar Polani , Sakthivel Manikandanesan , Venkatasamy Vettrichelvan , Ponnaiah Manickam , Murhekar Manoj
Published: March 2021

Background

India's National Health Profile (NHP) documents snakebite cases and deaths based on hospital-based reports, hence underrepresenting the actual burden. We describe secular trends of NHP data using population denominators for 2009–2018.

Methods

We abstracted the data on snakebite cases and deaths and calculated incidence and case fatality rate (CFR) by gender and by states using population denominators. We estimated the change in incidence and CFR over time by using a Poisson regression model. We computed the incidence rate ratio (IRR) and 95% confidence interval (CI) using Stata 14.0.

Results

The incidence of snakebites ranged from 89 to 141 per million population and without any specific pattern during 2009–2018 as per NHP reports. The incidence increased by 3% per year (IRR 1.03 [95% CI 0.99 to 1.07]). The incidence was higher among males (range 97–163) than females (range 71–115) and there was no difference in trends by gender (IRR 1.07 [95% CI 0.37 to 3.12]). The CFR was 5–13 deaths per 1000 cases, with an annual decline of 12% (IRR 0.88 [95% CI 0.85 to 0.92]). The CFR did not differ by gender (male 5–12, female 6–13; IRR 0.48 [95% CI 0.20 to 1.17]).

Conclusion

India's NHP snakebite data, representing an underestimate of the actual burden, suggests no specific secular trend and points to areas documenting consistent and significant burden.
Identifying and Addressing Statewide Nursing Simulation Needs
Authors: Herrington Alaina
Published: March 2021

A statewide simulation assessment was conducted in one southeastern state using the Program Assessment Survey for Simulation. Simulation coordinators from 22 prelicensure nursing programs were interviewed. The findings revealed several areas where faculty education was needed: theory, design, facilitation, debriefing, interprofessional education, and evaluation. A free online simulation fundamentals course was effective in addressing the areas where education was required.
Cochlear Implant Magnet Dislocation: Simulations and Measurements of Force and Torque at 1.5T Magnetic Resonance Imaging
Authors: Eerkens Hedwig J. , Smits Cas , Hofman Mark B. M.
Published: March 2021

Objectives:

Dislocation of the magnet inside the implanted component of a cochlear implant (CI) can be a serious risk for patients undergoing a magnetic resonance imaging (MRI) exam. CI manufacturers aim to reduce this risk either via the design of the implant magnet or magnet housing, or by advising a compression bandage and cover over the magnet. The aim of this study is to measure forces and torque on the magnet for different CI models and assess the effectiveness of the design and preventative measures on the probability of magnet dislocation.

Design:

Six CI models from four manufacturers covering all the current CI brands were included. Each model was positioned on a polystyrene head with compression bandage and magnet cover according to the recommendations of the manufacturer and tested for dislocation in a 1.5T whole-body MRI system. In addition, measurements of the displacement force in front of the MRI scanner and torque at the MRI scanner isocenter were obtained.

Results:

Chance of CI magnet dislocation was observed for two CI models. The design of the magnet or magnet housing of the other models proved sufficient to prevent displacement of the magnet. The main cause for magnet dislocation was found to be the rotational force resulting from the torque experienced inside the magnet bore, which ranges from 2.4 to 16.2 N between the models, with the displacement force being lower, ranging from 1.0 to 1.8 N.

Conclusions:

In vitro testing shows that two CI models are prone to the risk of magnet dislocation. In these CI models, preparation before MRI with special compression bandage and a stiff cover are of importance. But these do not eliminate the risk of pain and dislocation requiring patient consulting before an MRI exam. Newer models show a better design resulting in a significantly reduced risk of magnet dislocation.
Minimally Invasive Versus Standard Surgery in Idiopathic Scoliosis Patients
Authors: Sarwahi Vishal , Galina Jesse M. , Hasan Sayyida , Atlas Aaron , Ansorge Alexandre , De Bodman Charlotte , Lo Yungtai , Amaral Terry D. , Dayer Romain
Published: March 2021

Study Design.

Retrospective review of prospective case–control study.

Objective.

To compare minimally invasive scoliosis surgery (MIS) and posterior spinal fusion (PSF) in a large group of patients.

Summary of Background Data.

MIS, has been shown to have benefits over standard PSF in adolescent idiopathic scoliosis (AIS).

Methods.

Radiographic, clinical, and operative review of a multi-institutional prospective database from 2013 to 2018. MIS patients with minimum 2-year XR follow up were compared with open PSF technique patients.

Results.

Four hundred eighty five patients were included; 192 MIS and 293 PSF. Preoperative Cobb (P = 0.231) and kyphosis were similar (P = 0.501). Cobb correction was comparable (P = 0.46), however percent improvement in thoracic kyphosis was significantly higher in MIS (P < 0.001). MIS had significantly lower blood loss (P < 0.001), transfusions (P < 0.001), fixation points (P < 0.001), opioid consumption (P = 0.001), and hospital stay (P < 0.001). Operative time was shorter (P = 0.001) and 30-day complications rate was similar (P = 0.81).

Conclusion.

This is the largest study comparing the surgical outcomes of MIS and PSF. MIS patients benefit from increased kyphosis, fewer transfusion, lower opioid consumption, and shorter hospital stay with similar Cobb correction. Increased postoperative kyphosis is likely from muscle sparing dissection in MIS.

Level of Evidence: 3
National Rates, Reasons, and Risk Factors for 30- and 90-Day Readmission and Reoperation Among Patients Undergoing Anterior Cervical Discectomy and Fusion
Authors: Taylor Blake E.S. , Hilden Patrick , Hansen Rosemary T. Behmer , Nanda Anil , Gillick John L.
Published: March 2021

Study Design.

Retrospective cohort study of the Nationwide Readmissions Database (NRD).

Objective.

To determine causes of and independent risk factors for 30- and 90-day readmission in a cohort of anterior cervical discectomy and fusion (ACDF) patients.

Summary of Background Data.

Identifying populations at high-risk of 30-day readmission is a priority in healthcare reform so as to reduce cost and patient morbidity. However, among patients undergoing ACDF, nationally-representative data have been limited, and have seldom described 90-day readmissions, early reoperation, or socioeconomic influences.

Methods.

We queried the NRD, which longitudinally tracks 49.3% of hospitalizations, for all adult patients undergoing ACDF. We calculated the rates of, and determined reasons for, readmission and reoperation at 30 and 90 days, and determined risk factors for readmission at each timepoint.

Results.

We identified 50,126 patients between January and September 2014. Of these, 2294 (4.6%) and 4152 (8.3%) were readmitted within 30 and 90 days of discharge, respectively, and were most commonly readmitted for infections, medical complications, and dysphagia. The characteristics most strongly associated with readmission were Medicare or Medicaid insurance, length of stay greater than or equal to 4 days, three or more comorbidities, and non-routine discharge, whereas surgical factors (e.g., greater number of vertebrae fused) were more modest. By 30 and 90 days, 8.2% and 11.7% of readmitted patients underwent an additional spinal procedure, respectively.

Conclusion.

Our analysis uses the NRD to thoroughly characterize readmission in the general ACDF population. Readmissions are often delayed (after 30 days), strongly associated with insurance status, and many result in reoperation. Our results are crucial for risk-stratifying future ACDF patients and developing interventions to reduce readmission.

Level of Evidence: 3