bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review on the efficiency and accuracy of localization of moisture distributions sensing in agricultural silos
Authors: Almaleeh A A , Zakaria A , Zakaria S M M S , Kamarudin L M , Rahiman M H F , Sukor A S A , Rahim Y A , Adom A H
Published: December 2019

The moisture distribution in the silos depends upon various seeds parameters such as type and size of seeds, amount of storage, external weather, and storage period as well as structural and environmental factors. It is very difficult to predict moisture distribution in silos effectively while taking all the above aspects into consideration. This study aims to investigate the efficiency and accuracy of localization of moisture distributions sensing in agricultural silo. The work is mainly focussed on three major elements: Radio Frequency (RF), tomographic imaging and classification process using machine learning. In particular, RF-based signal and volume tomographic images are used to predict the moisture distribution. Furthermore, computational intelligence techniques such as artificial neural network (ANN) is applied to develop models based on previous data. The generalization of these models towards new set of data is discussed in making sure a successful application of a model. A detailed study of the relative performance of computational intelligence techniques has been carried out based on different statistical performance criteria.
Effect of La on microstructures and mechanical properties of Cu/Ti3SiC2/C nanocomposites sintered by vacuum hot-pressing and hot isostatic pressing
Authors: Lv Lan , Jiang Xiao-Song , Zhang Mei-Mei , Sun Hong-Liang , Shao Zhen-Yi , Fu Ning-Ning , Jin Wen-Tao
Published: December 2019

Researches have shown that the addition of trace amounts of rare earth element lanthanum (La) to the alloys and composites can significantly improve their microstructure and properties. In this work, Cu/Ti3SiC2/C composites with 0.05wt%, 0.1wt% and 0.3wt% La were prepared by powder metallurgy methodthrough mechanical alloying, hot-pressing (HP) and hot isostatic pressing (HIP). The effects of different La contents on the microstructure and mechanical properties of Cu/Ti3SiC2/C composites were investigated. The results show that La has a refinement effect on the grain of the matrix, and with the increase of La content, the size of the matrix of the composite becomes smaller. As the content of La increases, the performance of the composite exhibits a tendency to increase first and then decrease. The composite of 0.1wt% La exhibited the best performance with a hardness of 97.8 MPa, a tensile strength of 174.9 MPa, and a compressive strength and shear strength of 461.1 MPa and 102.1 MPa, respectively. Since the dimple is observed, the tensile fracture indicates that the fracture mode is a ductile fracture. The enhancement mechanism of La mainly includes dispersion strengthening and fine grain strengthening.
Effect of medication reconciliation interventions on outcomes: A systematic overview of systematic reviews
Authors: Anderson Laura J , Schnipper Jeff L , Nuckols Teryl K , Shane Rita , Le Michael M , Robbins Karen , Pevnick Joshua M ,   Members of the PHARM-DC group, Hughes Carmel , Jackevicius Cynthia A , O’Mahony Denis , Sarkisian Catherine
Published: December 2019

Purpose

To evaluate and summarize published evidence from systematic reviews examining medication reconciliation.

Methods

MEDLINE, the Cochrane Database of Systematic Reviews, and the Database of Abstracts of Reviews of Effects were searched for English-language systematic reviews published from January 2004 to March 2019. Reviewers independently extracted information and scored review quality using the Assessment of Multiple Systematic Reviews (AMSTAR) tool. For reviews with AMSTAR scores above 7, Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was applied to assess evidence quality, with evidence summarized and conclusions compared across reviews.

Results

Eleven reviews met the inclusion criteria, 5 of which used meta-analytic pooling. Most systematic reviews included primary studies of comprehensive bundled interventions that featured medication reconciliation as a central component. Reviews largely focused on transitions into and out of hospital settings. Five reviews focused exclusively on pharmacist-led interventions. Of the 5 reviews that considered all types of medication discrepancies, 3 reviews found very low-quality evidence that interventions reduced medication discrepancies. Neither of the 2 reviews that examined clinically significant medication discrepancies found any intervention effect. Of the 5 reviews that examined healthcare utilization outcomes, only 1 found any intervention effect, and that finding was based on low- to very low-quality evidence. Four reviews considered clinical outcomes, but none found any intervention effect.

Conclusion

An overview of systematic reviews of medication reconciliation interventions found 9 high-quality systematic reviews. A minority of those reviews’ conclusions were consistent with medication reconciliation alone having a measurable impact, and such conclusions were almost all based on very low-quality evidence.
Disentangling the effects of photosynthetically active radiation and red to far-red ratio on plant photosynthesis under canopy shading: a simulation study using a functional–structural plant model
Authors: Zhang Ningyi , van Westreenen Arian , Anten Niels P R , Evers Jochem B , Marcelis Leo F M
Published: December 2019

Background and Aims

Shading by an overhead canopy (i.e. canopy shading) entails simultaneous changes in both photosynthetically active radiation (PAR) and red to far-red ratio (R:FR). As plant responses to PAR (e.g. changes in leaf photosynthesis) are different from responses to R:FR (e.g. changes in plant architecture), and these responses occur at both organ and plant levels, understanding plant photosynthesis responses to canopy shading needs separate analysis of responses to reductions in PAR and R:FR at different levels.

Methods

In a glasshouse experiment we subjected plants of woody perennial rose (Rosa hybrida) to different light treatments, and so separately quantified the effects of reductions in PAR and R:FR on leaf photosynthetic traits and plant architectural traits. Using a functional–structural plant model, we separately quantified the effects of responses in these traits on plant photosynthesis, and evaluated the relative importance of changes of individual traits for plant photosynthesis under mild and heavy shading caused by virtual overhead canopies.

Key Results

Model simulations showed that the individual trait responses to canopy shading could have positive and negative effects on plant photosynthesis. Under mild canopy shading, trait responses to reduced R:FR on photosynthesis were generally negative and with a larger magnitude than effects of responses to reduced PAR. Conversely, under heavy canopy shading, the positive effects of trait responses to reduced PAR became dominant. The combined effects of low-R:FR responses and low-PAR responses on plant photosynthesis were not equal to the sum of the separate effects, indicating interactions between individual trait responses.

Conclusions

Our simulation results indicate that under canopy shading, the relative importance of plant responses to PAR and R:FR for plant photosynthesis changes with shade levels. This suggests that the adaptive significance of plant plasticity responses to one shading factor depends on plant responses to the other.
Follicular fluid steroid profile in sows: relationship to follicle size and oocyte quality†
Authors: Costermans N G J , Soede N M , van Tricht F , Blokland M , Kemp B , Keijer J , Teerds K J
Published: December 2019

Identification of reliable characteristics of follicle quality and developmental competence has been pursued in numerous studies, but with inconsistent outcomes. Here, we aimed to identify these characteristics by analysis of the follicular fluid (FF) steroid profile in relation to cumulus-oocyte complex (COC) morphology and follicle size, followed by molecular substantiation. Multiparous sows at weaning were used to facilitate analysis at the start of the follicular phase of the oestrus cycle. Sows with a higher average follicle size (≥5 mm vs. < 5 mm) had a higher follicular fluid β-estradiol concentration, but did not differ in other measured steroids. Sows with high compared to low percentage high-quality COCs (<70% vs. ≥70% high-quality) had follicular fluid with a higher concentration of β-estradiol, 19-norandrostenedione, progesterone, and α-testosterone, while the concentration of cortisol was lower. Transcriptome analysis of granulosa cells of healthy follicles of sows with a high percentage high-quality COCs showed higher abundance of transcripts involved in ovarian steroidogenesis (e.g., CYP19A2 and 3, POR, VEGFA) and growth (IGF1) and differential abundance of transcripts involved in granulosa cell apoptosis (e.g., GADD45A, INHBB). Differences in aromatase transcript abundance (CYP19A1, 2 and 3) were confirmed at the protein level. In addition, sows with a high percentage high-quality COCs lost less weight during lactation and had higher plasma IGF1 concentration at weaning, which may have affected COC quality. To the best of our knowledge, this study is also the first to report the relation between FF steroid profile and COC quality.
Condylar changes in patients with idiopathic condylar resorption: retrospective 2-year follow-up CBCT-based case–control study
Authors: Exposto Cristina R , Stoustrup Peter , Kristensen Kasper D , Dalstra Michel , Pedersen Thomas K
Published: December 2019

Objectives

To compare condylar development and changes in condylar radiological appearance in patients with idiopathic condylar resorption (ICR) to a healthy, age- and gender matched, control group.

Materials and methods

This case-control study included 16 ICR patients [mean age: 15years, 9 months; standard deviation (SD): 4 years) and 16 controls (mean age: 16 years, 8 months; SD: 4 years, 7 months), with diagnostic (T0) and 2-year follow-up (T1) CBCT examinations. Condylar changes were evaluated through changes in condylar neck angle (CNA), and the transversal, vertical and anteroposterior displacement of five condylar points between T0 and T1. The magnitude and direction of condylar changes were evaluated using vector analyses. A qualitative radiological evaluation of the TMJ was performed based on healthy, erosive and repaired morphological appearance. Linear and angular measurements were assessed using ANOVA and a Tukey post-hoc test, and vectors were tested using an independent-sample 2-tailed t-test. Fisher’s exact test was used for the qualitative evaluation.

Results

At T0, ICR patients exhibited decreased condylar height, smaller condylar width and posteriorly inclined CNA compared with the control group (P < 0.05). During observation, condylar vertical growth was smaller in the ICR group than in the control group (P < 0.05). Vector analysis showed an upward direction of vertical displacement for all condylar points in the control group; the ICR group showed a downward direction (P < 0.003). The radiological appearance of 75% of the ICR condyles and 94% of the control condyles did not change during the 2-year follow-up period.

Conclusions

ICR condyles displayed reduced vertical development compared with control condyles. The radiological appearance remained unchanged for most joints. Observed changes in radiological appearance did not always follow a progressive model of degenerative joint disease.
Low and elevated B-type natriuretic peptide levels are associated with increased mortality in patients with preserved ejection fraction undergoing transcatheter aortic valve replacement: an analysis of the PARTNER II trial and registry
Authors: Chen Shmuel , Redfors Bjorn , O’Neill Brian P , Clavel Marie-Annick , Pibarot Philippe , Elmariah Sammy , Nazif Tamim , Crowley Aaron , Ben-Yehuda Ori , Finn Matthew T , Alu Maria C , Vahl Torsten P , Kodali Susheel , Leon Martin B , Lindman Brian R
Published: December 2019

Aims

B-type natriuretic peptide (BNP) is a cardiac neurohormone that is secreted in response to ventricular volume expansion and pressure overload. There are conflicting data regarding the association between BNP levels and outcomes after transcatheter aortic valve replacement (TAVR). We therefore sought to assess the association between baseline BNP and adverse outcomes in patients with symptomatic, severe aortic stenosis (AS), and left ventricular ejection fraction (LVEF) ≥50%, undergoing TAVR in the PARTNER 2 Trial and Registry.

Methods and results

A total of 1782 patients were included in the analysis, and BNP was evaluated both as a continuous log-transformed value and by a priori categories: low (<50 pg/mL), normal (≥50 and <100 pg/mL), moderately elevated (≥100 and <400 pg/mL), or markedly elevated (≥400 pg/mL). Clinical outcomes from discharge to 2 years were compared between patients according to their baseline BNP level, using Kaplan–Meier event rates and multivariable Cox proportional hazards regression models. After adjustment, spline curves revealed a non-linear association between log-transformed BNP and all-cause and cardiovascular mortality in which both the lowest and highest values were associated with increased mortality. Two-year all-cause mortality rates for those with low (n = 86), normal (n = 202), moderately elevated (n = 885), and markedly elevated (n = 609) baseline BNP were 20.0%, 9.8%, 17.7%, and 26.1%, respectively. In adjusted models, compared to a normal baseline BNP, low [adjusted hazard ratio (HR) 2.6, 95% confidence interval (CI) 1.3–5.0, P-value 0.005], moderately elevated (adjusted HR 1.6, 95% CI 1.0–2.6, P-value 0.06), and markedly elevated (adjusted HR 2.1, 95% CI 1.3–3.5, P-value 0.003) BNP were associated with increased all-cause mortality, driven by cardiovascular mortality.

Conclusions

In a large cohort of patients with severe symptomatic AS and preserved LVEF undergoing TAVR, all-cause and cardiovascular mortality rates at 2 years were higher in patients with low and markedly elevated BNP levels.

Clinical Trial Registration

https://clinicaltrials.gov/ unique identifier #NCT01314313, #NCT02184442, #NCT03222128, and #NCT03222141.
Sex and gender in cardiovascular medicine: presentation and outcomes of acute coronary syndrome
Authors: Haider Ahmed , Bengs Susan , Luu Judy , Osto Elena , Siller-Matula Jolanta M , Muka Taulant , Gebhard Catherine
Published: December 2019

Although health disparities in women presenting with acute coronary syndrome (ACS) have received growing attention in recent years, clinical outcomes from ACS are still worse for women than for men. Women continue to experience higher patient and system delays and receive less aggressive invasive treatment and pharmacotherapies. Gender- and sex-specific variables that contribute to ACS vulnerability remain largely unknown. Notwithstanding the sex differences in baseline coronary anatomy and function, women and men are treated the same based on guidelines that were established from experimental and clinical trial data over-representing the male population. Importantly, younger women have a particularly unfavourable prognosis and a plethora of unanswered questions remains in this younger population. The present review summarizes contemporary evidence for gender and sex differences in vascular biology, clinical presentation, and outcomes of ACS. We further discuss potential mechanisms and non-traditional risk conditions modulating the course of disease in women and men, such as unrecognized psychosocial factors, sex-specific vascular and neural stress responses, and the potential impact of epigenetic modifications.
Influence of fault roughness on surface displacement: from numerical simulations to coseismic slip distributions
Authors: Bruhat Lucile , Klinger Yann , Vallage Amaury , Dunham Eric M
Published: December 2019

Field studies have characterized natural faults as rough, non-planar surfaces at all scales. Fault roughness induces local stress perturbations during slip, which dramatically affect rupture behaviour, resulting in slip heterogeneity. However, the relation between fault roughness and slip heterogeneity remains a key knowledge gap between current numerical and field studies. In this study, we analyse numerical simulations of earthquake rupture to determine how roughness influences final slip. Using a rupture catalogue containing thousands of dynamic rupture simulations on band-limited self-similar fractal fault profiles with varying roughness and background shear stress levels, we quantify how fault roughness affects the spectral characteristics of the resulting slip distribution. We find that slip distributions become increasingly more self-affine, that is, containing more short wavelength fluctuations as compared to the self-similar fault profiles, as roughness increases. We also find that, at very short wavelengths (<1 km), the fractal dimension of the slip distributions dramatically changes with increasing roughness, background shear stress, and rupture speed (sub-Rayleigh versus supershear). The existence of a critical wavelength around 1 km, under which more short wavelengths are either preserved or created, suggests the role of rupture process and dynamic effects, together with fault geometry, in controlling the final slip distributions. The same spectral analysis is performed on high-resolution coseismic surface slip distributions from a catalogue of real strike-slip earthquakes. Compared to numerical simulations, all earthquakes feature slip distributions that are much more self-affine than the slip distributions from numerical simulations. A different critical wavelength, here around 5–6 km, appears, potentially informing about a critical asperity length. While we show here that the relation between fault roughness and slip is much more complex than expected, this study is a first attempt at using statistical analyses of numerical simulations on rough faults to investigate observed coseismic slip distributions.
“Battling” for Legitimacy: Analyzing Performative Contests in the Gaza Flotilla Paradigmatic Case
Authors: Wajner Daniel F
Published: December 2019

How can we explain the dynamics of nonconventional struggles such as the Gaza flotilla case of May 2010? Most international relations scholars analyze international disputes using a “chess logic,” according to which the actors seek to outmaneuver their opponents on the battleground. However, an increasing number of clashes are guided by a “performance logic”: although the players interact with one another, their real targets are audiences. The present study aims to bridge this gap, proposing a phenomenological framework for analyzing this particular kind of performative contest over legitimation and delegitimation in contemporary conflicts. It expands upon the idea that current anarchical global politics increasingly lead contending actors to engage in “pure” legitimation struggles—“battles for legitimacy”—seeking to persuade international audiences that they deserve political support. After providing guidelines for the identification of these phenomena, this article presents a model for the methodical examination of their interactive dynamics based on three legitimation functions (appropriateness, consensus, empathy). This model is applied to the flotilla case by mapping the protagonists’ framing contests across “legitimation (battle)fields.” The findings of this study, which emphasize the strong interplay between normative, political, and emotional mechanisms for empowering (de)legitimation strategies, can contribute to expanding the research program concerning international legitimacy.
The Long-Term Effects of Long Terms – Compulsory Schooling Reforms in Sweden
Authors: Fischer Martin , Karlsson Martin , Nilsson Therese , Schwarz Nina
Published: December 2019

We evaluate the impact on earnings, pensions, and further labor market outcomes of two parallel educational reforms increasing instructional time in Swedish primary school. The reforms extended the annual term length and years of compulsory schooling by comparable amounts. We find striking differences in the effects of the two reforms: at 5% the returns to the term length extension were sizeable and benefited broad ranges of the population. The compulsory schooling extension had small (2%) albeit significant effects, which were possibly driven by an increase in post-compulsory schooling. Both reforms led to increased sorting into occupations with heavy reliance on basic skills and the term extension reduced the gender gap in employment and earnings.
Reversal of Resistance to the Larvicide Temephos in an Aedes aegypti (Diptera: Culicidae) Laboratory Strain From Cuba
Authors: Bisset Juan A , Rodríguez María M , Piedra Luis A , Cruz Modesto , Gutiérrez Gladys , Ruiz Armando
Published: December 2019

The objective of this investigation was to know whether the organophosphate temephos resistance developed in larvae from a laboratory strain of Aedes aegypti (Linnaeus, 1762) from Cuba could be reversed. The resistant laboratory strain of Ae. aegypti, named SAN-F6, was left without temephos selection pressure for 12 generations. The level of temephos resistance was determined using WHO bioassays and mechanisms of metabolic resistance were determined based on enzyme activity levels detected by biochemical assays. Bioassays and biochemical assays were conducted on the SAN-F6 parental strain and every three reversal generations (SANRevF3, SANRevF6, SANRevF9, and SANRevF12) without temephos selection pressure. After 19 yr of keeping the SAN-F6 strain under selection pressure with the LC90 of temephos, the resistance ratio (RR50) was 47.5×. Biochemical assays indicated that esterase and glutathione S-transferase are still responsible for temephos resistance in this strain, but not mixed-function oxidase. Experiments on resistance reversal showed that temephos susceptibility could be recovered as α esterase activity levels decreased. The SAN-F6 strain has provided an essential basis for studies of temephos resistance in Cuba. It was demonstrated that the resistance developed to the larvicide temephos in Ae. aegypti from this Cuban lab strain is a reversible phenomenon, which suggests that similar outcomes might be expected in field populations. As such, the use of temephos alternated with other larvicides recommended by WHO such as Bti or pyriproxyfen is recommended to maintain the effectiveness of temephos and to achieve more effective control of Ae. aegypti.
Immunosuppressant-induced late acute pancreatitis after laparoscopic sleeve gastrectomy: a case report and literature review
Authors: AlQahtani Awadh , Alali Mohammed N , Allehiani Safaa
Published: December 2019

Acute pancreatitis (AP) is a serious life-threatening condition, especially in high-risk patients. Limited data exist regarding early and late complications of immunosuppressant drugs as a cause of pancreatitis, especially Tacrolimus and Mycophenolate Mofetil (MMF), after transplantation. We report a rare case of late AP secondary to immunosuppressants’ synergistic effect after 5 years of renal transplant in an obese patient on day 4 after laparoscopic sleeve gastrectomy (LSG). We present a 41-year-old Saudi obese male patient, known to have multiple comorbidities and a renal transplantation twice, was on multiple medications, including Prednisolone, MMF and Tacrolimus for 5 years. On day 4 post-LSG, he developed severe epigastric abdominal pain and was diagnosed to have AP as a late complication of immunosuppressants’ synergistic effect. LSG is a common safe procedure, but complications related to medical illnesses or medications can occur. Careful review and sufficient knowledge of early and late complications are required.
Discovery of a soft X-ray lag in the ultraluminous X-ray source NGC 1313 X-1
Authors: Kara E , Pinto C , Walton D J , Alston W N , Bachetti M , Barret D , Brightman M , Canizares C R , Earnshaw H P , Fabian A C , Fürst F , Kosec P , Middleton M J , Roberts T P , Soria R , Tao L , Webb N A
Published: December 2019

Ultraluminous X-ray sources (ULXs) provide a unique opportunity to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddington accretion are not well understood, and so studying correlated variability between different energy bands can provide insights into the causal connection between different emitting regions. We present a spectral-timing analysis of NGC 1313 X-1 from a recent XMM–Newton campaign. The spectra can be decomposed into two thermal-like components, the hotter of which may originate from the inner accretion disc, and the cooler from an optically thick outflow. We find correlated variability between hard (2–10 keV) and soft (0.3–2 keV) bands on kilosecond time-scales, and find a soft lag of ∼150 s. The covariance spectrum suggests that emission contributing to the lags is largely associated with the hotter of the two thermal-like components, likely originating from the inner accretion flow. This is only the third ULX to exhibit soft lags. The lags range over three orders of magnitude in amplitude, but all three are ∼5–20 per cent of the corresponding characteristic variability time-scales. If these soft lags can be understood in the context of a unified picture of ULXs, then lag time-scales may provide constraints on the density and extent of radiatively driven outflows.
A super-Earth and a mini-Neptune around Kepler-59
Authors: Saad-Olivera X , Martinez C F , Costa de Souza A , Roig F , Nesvorný D
Published: December 2019

We characterize the radii and masses of the star and planets in the Kepler-59 system, as well as their orbital parameters. The star parameters are determined through a standard spectroscopic analysis, resulting in a mass of $1.359\pm 0.155\, \mathrm{M}_\odot$ and a radius of $1.367\pm 0.078\, \mathrm{R}_\odot$. The obtained planetary radii are $1.5\pm 0.1\, R_\oplus$ for the inner and $2.2\pm 0.1\, R_\oplus$ for the outer planet. The orbital parameters and the planetary masses are determined by the inversion of Transit Timing Variations (TTV) signals. We consider two different data sets: one provided by Holczer et al. (2016), with TTVs only for Kepler-59c, and the other provided by Rowe et al. (2015), with TTVs for both planets. The inversion method applies an algorithm of Bayesian inference (MultiNest) combined with an efficient N-body integrator (Swift). For each of the data set, we found two possible solutions, both having the same probability according to their corresponding Bayesian evidences. All four solutions appear to be indistinguishable within their 2-σ uncertainties. However, statistical analyses show that the solutions from Rowe et al. (2015) data set provide a better characterization. The first solution infers masses of $5.3_{-2.1}^{+4.0}~M_{\mathrm{\oplus }}$ and $4.6_{-2.0}^{+3.6}~M_{\mathrm{\oplus }}$ for the inner and outer planet, respectively, while the second solution gives masses of $3.0^{+0.8}_{-0.8}~M_{\mathrm{\oplus }}$ and $2.6^{+0.9}_{-0.8}~M_{\mathrm{\oplus }}$. These values point to a system with an inner super-Earth and an outer mini-Neptune. A dynamical study shows that the planets have almost co-planar orbits with small eccentricities (e < 0.1), close to the 3:2 mean motion resonance. A stability analysis indicates that this configuration is stable over million years of evolution.
Discrimination of heavy elements originating from Pop III stars in z = 3 intergalactic medium
Authors: Kirihara Takanobu , Hasegawa Kenji , Umemura Masayuki , Mori Masao , Ishiyama Tomoaki
Published: December 2019

We investigate the distribution of metals in the cosmological volume at $z$ ∼ 3, in particular, provided by massive Population III (Pop III) stars using a cosmological N-body simulation in which a model of Pop III star formation is implemented. Owing to the simulation, we can choose minihaloes where Pop III star formation occurs at $z$ > 10 and obtain the spatial distribution of the metals at lower redshifts. To evaluate the amount of heavy elements provided by Pop III stars, we consider metal yield of pair-instability or core-collapse supernovae (SNe) explosions of massive stars. By comparing our results to the Illustris-1 simulation, we find that heavy elements provided by Pop III stars often dominate those from galaxies in low-density regions. The median value of the volume averaged metallicity is $Z\sim 10^{-4.5 - -2} \, \mathrm{Z}_{\odot }$ at the regions. Spectroscopic observations with the next generation telescopes are expected to detect the metals imprinted on quasar spectra.
Filaments and striations: anisotropies in observed, supersonic, highly magnetized turbulent clouds
Authors: Beattie James R , Federrath Christoph
Published: December 2019

Stars form in highly magnetized, supersonic turbulent molecular clouds. Many of the tools and models that we use to carry out star formation studies rely upon the assumption of cloud isotropy. However, structures like high-density filaments in the presence of magnetic fields and magnetosonic striations introduce anisotropies into the cloud. In this study, we use the two-dimensional power spectrum to perform a systematic analysis of the anisotropies in the column density for a range of Alfvén Mach numbers ($\operatorname{\mathcal {M}_{\text{A}}}=0.1{\!-\!10}$) and turbulent Mach numbers ($\operatorname{\mathcal {M}}=2{\!-\!20}$), with 20 high-resolution, three-dimensional turbulent magnetohydrodynamic simulations. We find that for cases with a strong magnetic guide field, corresponding to $\operatorname{\mathcal {M}_{\text{A}}}\lt 1$, and $\operatorname{\mathcal {M}}\lesssim 4$, the anisotropy in the column density is dominated by thin striations aligned with the magnetic field, while for $\operatorname{\mathcal {M}}\gtrsim 4$ the anisotropy is significantly changed by high-density filaments that form perpendicular to the magnetic guide field. Indeed, the strength of the magnetic field controls the degree of anisotropy and whether or not any anisotropy is present, but it is the turbulent motions controlled by $\operatorname{\mathcal {M}}$ that determine which kind of anisotropy dominates the morphology of a cloud.
Disentangling cataclysmic variables in Gaia’s HR diagram
Authors: Abril Javier , Schmidtobreick Linda , Ederoclite Alessandro , López-Sanjuan Carlos
Published: December 2019

Cataclysmic variables (CVs) are interacting binaries consisting of at least three components that control their colour and magnitude. Using Gaia, we here investigate the influence of the physical properties of these binaries on their position in the Hertzsprung–Russell (HR) diagram. The CVs are on average located between the main sequence and the white dwarf regime, the maximum density being at GBP − GRP ∼ 0.56 and Gabs ∼ 10.15. We find a trend of the orbital period with colour and absolute brightness: with decreasing period, the CVs become bluer and fainter. We also identify the location of the various CV subtypes in the HR diagram and discuss the possible location of detached CVs, going through the orbital period gap.
First evidence of introgressive hybridization of apple snails (Pomacea spp.) in their native range
Authors: Glasheen Paul M , Burks Romi L , Campos Sofia R , Hayes Kenneth A
Published: December 2019

Genetic variation facilitates both natural range expansions and anthropogenic invasions. Contrary to expectations, hybridization does not always impact negatively on biodiversity. Increasing evidence indicates advantageous roles for introgressive hybridization in maintaining standing genetic variation. Hypothesizing that hybridization may contribute to the evolutionary and invasive success of a diverse group of freshwater snails (Ampullariidae, commonly known as apple snails), we estimated the frequency of hybridization between two globally invasive species of Pomacea, Pomacea canaliculata (Lamarck, 1822) and P. maculata Perry, 1810, in their native range. While previous work in Asia has uncovered the occurrence of extensive hybridization, we provide the first phylogenetic evidence of a high degree of hybridization (30%) between these species in Uruguay and Brazil. Hybrids carried both heterozygous and homozygous combinations of elongation factor 1-α (EF1α) nuclear alleles in both mating directions, indicating that hybridization has occurred over multiple generations and likely preceded introductions outside the native range. Among the five sites in Brazil previously documented as containing only P. maculata, one far northern population (Careiro Castanho), which is thousands of kilometres from the northern range of P. canaliculata, unexpectedly contained hybrids. This may be the result of human-facilitated introductions. Together with recent work from Asia, our investigations in the native range of apple snails support a reframing of historical perspectives of hybridization as a driver of extinction and diversity loss towards a modern paradigm where hybridization may promote diversification and contribute to the survival of evolutionary lineages such as molluscs.
53BP1/RIF1 signaling promotes cell survival after multifractionated radiotherapy
Authors: Eke Iris , Zong Dali , Aryankalayil Molykutty J , Sandfort Veit , Bylicky Michelle A , Rath Barbara H , Graves Edward E , Nussenzweig André , Coleman C Norman
Published: December 2019

Multifractionated irradiation is the mainstay of radiation treatment in cancer therapy. Yet, little is known about the cellular DNA repair processes that take place between radiation fractions, even though understanding the molecular mechanisms promoting cancer cell recovery and survival could improve patient outcome and identify new avenues for targeted intervention. To address this knowledge gap, we systematically characterized how cells respond differentially to multifractionated and single-dose radiotherapy, using a combination of genetics-based and functional approaches. We found that both cancer cells and normal fibroblasts exhibited enhanced survival after multifractionated irradiation compared with an equivalent single dose of irradiation, and this effect was entirely dependent on 53BP1-mediated NHEJ. Furthermore, we identified RIF1 as the critical effector of 53BP1. Inhibiting 53BP1 recruitment to damaged chromatin completely abolished the survival advantage after multifractionated irradiation and could not be reversed by suppressing excessive end resection. Analysis of the TCGA database revealed lower expression of 53BP1 pathway genes in prostate cancer, suggesting that multifractionated radiotherapy might be a favorable option for radio-oncologic treatment in this tumor type. We propose that elucidation of DNA repair mechanisms elicited by different irradiation dosing regimens could improve radiotherapy selection for the individual patient and maximize the efficacy of radiotherapy.
Integrative analyses of noncoding RNAs reveal the potential mechanisms augmenting tumor malignancy in lung adenocarcinoma
Authors: Shih Jou-Ho , Chen Hsin-Yi , Lin Shin-Chih , Yeh Yi-Chen , Shen Roger , Lang Yaw-Dong , Wu Dung-Chi , Chen Chien-Yu , Chen Ruey-Hwa , Chou Teh-Ying , Jou Yuh-Shan
Published: December 2019

Precise noncoding RNA (ncRNA)-based network prediction is necessary to reveal ncRNA functions and pathological mechanisms. Here, we established a systemic pipeline to identify prognostic ncRNAs, predict their functions and explore their pathological mechanisms in lung adenocarcinoma (LUAD). After in silico and experimental validation based on evaluations of prognostic value in multiple LUAD cohorts, we selected the PTTG3P pseudogene from among other prognostic ncRNAs (MIR497HG, HSP078, TBX5-AS1, LOC100506990 and C14orf64) for mechanistic studies. PTTG3P upregulation in LUAD cells shortens the metaphase to anaphase transition in mitosis, increases cell viability after cisplatin or paclitaxel treatment, facilitates tumor growth that leads to poor survival in orthotopic lung models, and is associated with a poor survival rate in LUAD patients in the TCGA cohort who received chemotherapy. Mechanistically, PTTG3P acts as an ncRNA that interacts with the transcription factor FOXM1 to regulate the transcriptional activation of the mitotic checkpoint kinase BUB1B, which augments tumor growth and chemoresistance and leads to poor outcomes for LUAD patients. Overall, we established a systematic strategy to uncover prognostic ncRNAs with functional prediction methods suitable for pan-cancer studies. Moreover, we revealed that PTTG3P, due to its upregulation of the PTTG3P/FOXM1/BUB1B axis, could be a therapeutic target for LUAD patients.
AtFKBP53: a chimeric histone chaperone with functional nucleoplasmin and PPIase domains
Authors: Singh Ajit Kumar , Datta Aritreyee , Jobichen Chacko , Luan Sheng , Vasudevan Dileep
Published: December 2019

FKBP53 is one of the seven multi-domain FK506-binding proteins present in Arabidopsis thaliana, and it is known to get targeted to the nucleus. It has a conserved PPIase domain at the C-terminus and a highly charged N-terminal stretch, which has been reported to bind to histone H3 and perform the function of a histone chaperone. To better understand the molecular details of this PPIase with histone chaperoning activity, we have solved the crystal structures of its terminal domains and functionally characterized them. The C-terminal domain showed strong PPIase activity, no role in histone chaperoning and revealed a monomeric five-beta palm-like fold that wrapped over a helix, typical of an FK506-binding domain. The N-terminal domain had a pentameric nucleoplasmin-fold; making this the first report of a plant nucleoplasmin structure. Further characterization revealed the N-terminal nucleoplasmin domain to interact with H2A/H2B and H3/H4 histone oligomers, individually, as well as simultaneously, suggesting two different binding sites for H2A/H2B and H3/H4. The pentameric domain assists nucleosome assembly and forms a discrete complex with pre-formed nucleosomes; wherein two pentamers bind to a nucleosome.
A versatile cis-acting element reporter system to study the function, maturation and stability of ribosomal RNA mutants in archaea
Authors: Jüttner Michael , Weiß Matthias , Ostheimer Nina , Reglin Corinna , Kern Michael , Knüppel Robert , Ferreira-Cerca Sébastien
Published: December 2019

General molecular principles of ribosome biogenesis have been well explored in bacteria and eukaryotes. Collectively, these studies have revealed important functional differences and few similarities between these processes. Phylogenetic studies suggest that the information processing machineries from archaea and eukaryotes are evolutionary more closely related than their bacterial counterparts. These observations raise the question of how ribosome synthesis in archaea may proceed in vivo. In this study, we describe a versatile plasmid-based cis-acting reporter system allowing to analyze in vivo the consequences of ribosomal RNA mutations in the model archaeon Haloferax volcanii. Applying this system, we provide evidence that the bulge-helix-bulge motif enclosed within the ribosomal RNA processing stems is required for the formation of archaeal-specific circular-pre-rRNA intermediates and mature rRNAs. In addition, we have collected evidences suggesting functional coordination of the early steps of ribosome synthesis in H. volcanii. Together our investigation describes a versatile platform allowing to generate and functionally analyze the fate of diverse rRNA variants, thereby paving the way to better understand the cis-acting molecular determinants necessary for archaeal ribosome synthesis, maturation, stability and function.
Protein unties the pseudoknot: S1-mediated unfolding of RNA higher order structure
Authors: Lund Paul E , Chatterjee Surajit , Daher May , Walter Nils G
Published: December 2019

Ribosomal protein S1 plays important roles in the translation initiation step of many Escherichia coli mRNAs, particularly those with weak Shine-Dalgarno sequences or structured 5′ UTRs, in addition to a variety of cellular processes beyond the ribosome. In all cases, the RNA-binding activity of S1 is a central feature of its function. While sequence determinants of S1 affinity and many elements of the interactions of S1 with simple secondary structures are known, mechanistic details of the protein's interactions with RNAs of more complex secondary and tertiary structure are less understood. Here, we investigate the interaction of S1 with the well-characterized H-type pseudoknot of a class-I translational preQ1 riboswitch as a highly structured RNA model whose conformation and structural dynamics can be tuned by the addition of ligands of varying binding affinity, particularly preQ1, guanine, and 2,6-diaminopurine. Combining biochemical and single molecule fluorescence approaches, we show that S1 preferentially interacts with the less folded form of the pseudoknot and promotes a dynamic, partially unfolded conformation. The ability of S1 to unfold the RNA is inversely correlated with the structural stability of the pseudoknot. These mechanistic insights delineate the scope and limitations of S1-chaperoned unfolding of structured RNAs.
Stereotactic radiosurgery for non-functioning pituitary adenomas: meta-analysis and International Stereotactic Radiosurgery Society practice opinion
Authors: Kotecha Rupesh , Sahgal Arjun , Rubens Muni , De Salles Antonio , Fariselli Laura , Pollock Bruce E , Levivier Marc , Ma Lijun , Paddick Ian , Regis Jean , Sheehan Jason , Yomo Shoji , Suh John H
Published: December 2019

Background

This systematic review reports on outcomes and toxicities following stereotactic radiosurgery (SRS) for non-functioning pituitary adenomas (NFAs) and presents consensus opinions regarding appropriate patient management.

Methods

Using the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic review was performed from articles of ≥10 patients with NFAs published prior to May 2018 from the Medline database using the key words “radiosurgery” and “pituitary” and/or “adenoma.” Weighted random effects models were used to calculate pooled outcome estimates.

Results

Of the 678 abstracts reviewed, 35 full-text articles were included describing the outcomes of 2671 patients treated between 1971 and 2017 with either single fraction SRS or hypofractionated stereotactic radiotherapy (HSRT). All studies were retrospective (level IV evidence). SRS was used in 27 studies (median dose: 15 Gy, range: 5–35 Gy) and HSRT in 8 studies (median total dose: 21 Gy, range: 12–25 Gy, delivered in 3–5 fractions). The 5-year random effects local control estimate after SRS was 94% (95% CI: 93.0–96.0%) and 97.0% (95% CI: 93.0–98.0%) after HSRT. The 10-year local control random effects estimate after SRS was 83.0% (95% CI: 77.0–88.0%). Post-SRS hypopituitarism was the most common treatment-related toxicity observed, with a random effects estimate of 21.0% (95% CI: 15.0–27.0%), whereas visual dysfunction or other cranial nerve injuries were uncommon (range: 0–7%).

Conclusions

SRS is an effective and safe treatment for patients with NFAs. Encouraging short-term data support HSRT for select patients, and mature outcomes are needed before definitive recommendations can be made. Clinical practice opinions were developed on behalf of the International Stereotactic Radiosurgery Society (ISRS).
A Forced-Choice Procedure to Assess the Acute Relative Reinforcing Effects of Nicotine Dose per se in Humans
Authors: Perkins Kenneth A , Karelitz Joshua L
Published: December 2019

Introduction

A method to assess acute reinforcement due to nicotine may aid identification of doses needed to maintain dependence. After describing development of a forced-choice procedure, results are presented from two studies using it to determine the relative reinforcing effects of nicotine dose per se.

Aims and Methods

Choice between a higher versus a very low or no nicotine option, via smoking (Study 1, n = 59) and via nasal spray (Study 2, n = 42), was assessed in nontreatment-seeking dependent smokers abstinent overnight. Using a within-subject design, different nicotine levels for each product were administered under blind conditions, initially to assess their discriminability (Study 1: 1.3–17 mg/g each vs. 0.4 mg/g nicotine Spectrum cigarettes; Study 2: 2.5 µg/kg vs. 0 µg/kg nicotine per spray). At the end of sessions for each study, participants engaged in forced-choice trials to assess preference, requiring a fixed number of puffs/sprays for one and/or the other.

Results

Confirming the procedure’s validity, the choice of the higher nicotine option was significantly greater than that for the very low or no nicotine option in both studies. In Study 1, choice relative to 0.4 mg/g was greater for cigarettes 5.3 mg/g or more but not 2.3 mg/g or less (p = .003 for the interaction of higher content vs. 0.4 mg/g comparison). In Study 2, choice was greater for the nicotine versus placebo spray (p < .005), as nicotine was preferred nearly twice as much as the placebo.

Conclusion

This forced-choice procedure may efficiently determine the relative reinforcing value of a nicotine dose per se.

Implications

The forced-choice procedure described here may identify nicotine doses that are acutely reinforcing in dependent smokers. A priori research of choice comparisons between small versus zero nicotine doses could inform clinical research in larger and more diverse samples to determine nicotine contents in cigarettes, and perhaps in other commercial products, that are not reinforcing and, thus, likely to reduce the risk of their addictiveness. This procedure may also be applicable to assessing changes in acute nicotine reinforcement due to different product formulations, novel drugs, or other manipulations, perhaps helping inform development of new interventions for cessation or harm reduction.
Current explorations of nutrition and the gut microbiome: a comprehensive evaluation of the review literature
Authors: Frame Leigh A , Costa Elise , Jackson Scott A
Published: December 2019

Context

The ability to measure the gut microbiome led to a surge in understanding and knowledge of its role in health and disease. The diet is a source of fuel for and influencer of composition of the microbiome.

Objective

To assess the understanding of the interactions between nutrition and the gut microbiome in healthy adults.

Data Sources

PubMed and Google Scholar searches were conducted in March and August 2018 and were limited to the following: English, 2010–2018, healthy adults, and reviews.

Data Extraction

A total of 86 articles were independently screened for duplicates and relevance, based on preidentified inclusion criteria.

Data Analysis

Research has focused on dietary fiber – microbiota fuel. The benefits of fiber center on short-chain fatty acids, which are required by colonocytes, improve absorption, and reduce intestinal transit time. Contrastingly, protein promotes microbial protein metabolism and potentially harmful by-products that can stagnate in the gut. The microbiota utilize and produce micronutrients; the bidirectional relationship between micronutrition and the gut microbiome is emerging.

Conclusions

Nutrition has profound effects on microbial composition, in turn affecting wide-ranging metabolic, hormonal, and neurological processes. There is no consensus on what defines a “healthy” gut microbiome. Future research must consider individual responses to diet.