bluuebunny/crossref_metadata_2025 huggingface dataset:
Shimiella gen. nov. and Shimiella gracilenta sp. nov. (Dinophyceae, Kareniaceae), a Kleptoplastidic Dinoflagellate from Korean Waters and its Survival under Starvation
Authors: Ok Jin Hee , Jeong Hae Jin , Lee Sung Yeon , Park Sang Ah , Noh Jae Hoon
Published: September 2020

A small dinoflagellate, ~13 μm in cell length, was isolated from Jinhae Bay, Korea. Light microscopy showed that it was similar to the kleptoplastidic dinoflagellate Gymnodinium gracilentum nom. inval. rDNA sequences were obtained and its anatomy and morphology described using light and scanning and transmission electron microscopy. Phylogenetic analyses indicated that it belonged to the family Kareniaceae. However, its large subunit (LSU) rDNA sequences were 5.2–9.5% different from those of the other five genera in the family, and its clade was clearly divergent from that of each genus. Its overall morphology was different from those of the other five genera in the family and from Gymnodinium. Unlike Gymnodinium, this dinoflagellate did not have a horseshoe‐shaped apical groove, nuclear envelope chambers, or a nuclear fibrous connective (NFC). It had an apical line of narrow amphiesmal vesicles and an elongated apical furrow crossing the apex. Cells were covered with polygonal amphiesmal vesicles arranged in 16 rows. Starved cells did not contain their own plastids, eyespots, pyrenoids, peridinin, or fucoxanthin. However, they could survive without added prey for approximately one month using chloroplasts from the cryptophyte prey Teleaulax amphioxeia, indicating kleptoplastidy. Because this taxon is genetically distinct at the generic rank from the other genera in Kareniaceae, it is placed in Shimiella gen. nov., and because G. gracilentum was invalid, the new bionomial S. gracilenta sp. nov. is proposed.
Synchronous distance education vs traditional education for health science students: A systematic review and meta‐analysis
Authors: He Liyun , Yang Na , Xu Lingling , Ping Fan , Li Wei , Sun Qi , Li Yuxiu , Zhu Huijuan , Zhang Huabing
Published: September 2020

Context

Synchronous distance education (SDE) has been widely used for health science students in recent years. This study examined the effectiveness and acceptance of SDE compared with traditional education for health science students and explored the potential moderators that could impact the pooled results.

Methods

A systematic review and meta‐analysis was conducted of randomised controlled trials (RCTs) from January 2000 to March 2020 searched on nine electronic databases, including Web of Science, PubMed, Cochrane Library, Scopus, EMBASE, CINAHL, ERIC, PsycINFO, and ProQuest Dissertations and Theses. The outcomes measured were knowledge, skills with objective assessments and overall satisfaction with subjective evaluations. The pooled results were calculated using random‐model effects, and moderators were explored through meta‐regression.

Results

A total of seven RCTs with 594 participants were included. At the post‐test level, the pooled effect size of knowledge acquisitions (SMD 0.12, 95% CI −0.07‐0.32) showed insignificant difference between the SDE and traditional education groups (P = .207), with low heterogeneity (I2 = 17.6%). Subgroup analyses observed no factors that significantly impacted the pooled results of knowledge acquisition at the post‐test levels (P for interaction > 0.05). Knowledge gains from pretest to post‐test in SDE groups also did not differ significantly between groups (SMD 0.15, 95% CI −0.22‐0.53; P = .428). The pooled effect size of skills (SMD 0.02, 95% CI −0.24‐0.28; P = .735) was similarly insignificant. The pooled effect size of overall satisfaction (SMD 0.60, 95% CI 0.38‐0.83; P < .001) significantly favoured SDE over traditional education. Incorporating two‐group studies without randomisations did not significantly change the overall results of knowledge acquisition at the post‐test level (SMD −0.002, 95% CI −0.11‐0.10; P = .994), with moderate heterogeneity (I2 = 61.9%).

Conclusions

Synchronous distance education was not significantly different from traditional education in effectiveness and had higher satisfaction ratings. Our findings might provide indications for adoptions of online remote education in health science education centres.
The public health rationale for increasing dietary fibre: Health benefits with a focus on gut microbiota
Authors: Koç F. , Mills S. , Strain C. , Ross R. P. , Stanton C.
Published: September 2020

Dietary fibre can be considered an essential macronutrient which feeds our gut microbiota, thus enabling the optimal functioning of this ‘virtual organ’. Recommended daily intakes range from 25 to 38 g/day. However, most individuals fail to reach this target and may consume <50% of the recommended amount. Poor dietary fibre intake is associated with an imbalanced gut microbiota leading to reduced diversity and increased abundance of non‐beneficial microorganisms at the expense of beneficial ones. Inflammation is a recognised physiological effect of such a microbiome structure and is a common denominator in several non‐communicable diseases associated with the Western lifestyle/developed world including obesity, cardiovascular disease, type 2 diabetes and colorectal cancer. Yet increasing dietary fibre intake can reduce risk factors associated with these diseases and may even improve prognosis. Several food manufacturers have now developed strategies to increase the fibre content of foods. However, research gaps still remain. In particular, dietary fibre is composed of various non‐digestible carbohydrates and the exact effect of each of these on the gut microbiota is currently unknown. The links between dietary fibre and disease risk are generally associative. Understanding the biological mechanisms will require deeper insight into the impact of the gut microbiota on health. Furthermore, gut microbiota research has shown significant inter‐individual variation meaning that some individuals may not respond to certain dietary fibres owing to the absence of specific microorganisms. Understanding how the different fibre types influence the microbiota, combined with knowledge of an individual’s microbiota, should lead to fibre‐led, microbiota‐based dietary advice.
Is wonder at the scientific enterprise good for us, and for our relationship to the natural world?
Authors: Sideris Lisa H.
Published: September 2020

Wonder is often assumed, without question, to be a good thing. As a response to the world around us, however, wonder is as complex and multifaceted as it is celebrated. This essay attempts to shine a critical light on expressions of wonder that privilege wonder at science and scientific knowledge over and above experiences of wonder in the natural world, as set forth by Richard Dawkins and E. O. Wilson.
Prognostic value of preoperative lymphocyte‐to‐monocyte ratio in oral cancer patients and establishment of a dynamic nomogram
Authors: Chen Lin , Qian Jiawen , Lin Lisong , Lin Jing , Chen Qing , Zhuang Zhaocheng , Hong Yihong , Wang Jing , Qiu Yu , Pan Lizhen , Shi Bin , Wang Jing , Liu Fengqiong , Cai Lin , Hu Zhijian , He Baochang , Chen Fa
Published: September 2020

Objective

To assess the association of preoperative lymphocyte‐to‐monocyte ratio (LMR) and overall survival (OS) in patients with oral cancer and develop a dynamic nomogram for individualized survival prediction.

Method

The prognostic value of LMR was evaluated in a large‐scale cohort with 651 postoperative patients with oral cancer between January 2010 and December 2017. Propensity score‐matched (PSM) analysis and inverse probability of treatment weighting (IPTW) analysis were performed to further verify the prognostic value of LMR. A dynamic nomogram was then developed based on the LMR and clinicopathological features, and its predictive performance and clinical utility were evaluated.

Results

A high LMR was significantly associated with better OS of patients with oral cancer (HR = 0.65; 95% CI = 0.44–0.98). The similar association was also observed in the PSM and IPTW analyses. Moreover, compared with TNM staging system, the dynamic nomogram based on the LMR exhibited more excellent predictive performance (0.72 versus 0.64, p < .001), with calibration curves (1,000 bootstrap resamples) suggesting good match between the actual and predicted probabilities. Decision curve analyses (DCAs) showed a more significant positive net benefit in the practical ranges of threshold probabilities using the dynamic nomogram.

Conclusion

Preoperative LMR may serve as an easily accessible and non‐invasive prognostic biomarker for predicting the prognosis of patients with oral cancer. A dynamic nomogram based on the LMR may show more convenience in survival prediction for patients with oral cancer. Further future studies are warranted to confirm our findings.
Hormonal adjustments to future expectations impact growth and survival in juvenile fish
Authors: Håkonsrud Jensen Camilla , Weidner Jacqueline , Giske Jarl , Budaev Sergey , Jørgensen Christian , Eliassen Sigrunn
Published: September 2020

Evolutionary ecology often studies how environmental factors define optimal phenotypes without considering the bodily mechanisms involved in their regulation. Here we used a dynamic optimisation model to investigate optimally concerted hormonal control of the phenotype. We studied a semi‐realistic situation where hormonal control of appetite, metabolism and growth acts to prepare juvenile fish for an uncertain future with regard to food availability. We found a bottom–up effect in that hormone levels varied across environments and affected a range of phenotypic changes. We also describe a top–down effect as natural selection varied across environments, which affected evolutionary optimisation of hormone levels. These combined top–down and bottom–up effects produced a hormone‐regulated phenotype that adjusted its foraging intensity and risk‐taking in adaptive ways depending on the differences between current and expected long‐term environmental conditions. Hence, understanding the response of these fish to their current conditions also requires an understanding of their future expectations. We found that when food availability was low, it was optimal for the juvenile fish to have low growth hormone, thyroid hormone and orexin levels, contrary to when food availability was high when these levels were higher. Individual variation emerged from the individually experienced food availability trajectories: Those that on average experienced higher food availability grew faster and had higher short‐term mortality risk. They also had higher survival probability throughout the growth period. The opposite was true for individuals experiencing lower food availability. Hormonal mechanisms that often are overlooked by ecologists are thus important in the ultimate adaptive control of both behaviour and physiology, thereby impacting fitness through growth and survival.
Who Is a Better Decision Maker? Data‐Driven Expert Ranking Under Unobserved Quality
Authors: Geva Tomer , Saar‐Tsechansky Maytal
Published: September 2020

The capacity to rank expert workers by their decision quality is a key managerial task of substantial significance to business operations. However, when no ground truth information is available on experts’ decisions, the evaluation of expert workers typically requires enlisting peer‐experts, and this form of evaluation is prohibitively costly in many important settings. In this work, we develop a data‐driven approach for producing effective rankings based on the decision quality of expert workers; our approach leverages historical data on past decisions, which are commonly available in organizational information systems. Specifically, we first formulate a new business data science problem: Ranking Expert decision makers’ unobserved decision Quality (REQ) using only historical decision data and excluding evaluation by peer experts. The REQ problem is challenging because the correct decisions in our settings are unknown (unobserved) and because some of the information used by decision makers might not be available for retrospective evaluation. To address the REQ problem, we develop a machine‐learning–based approach and analytically and empirically explore conditions under which our approach is advantageous. Our empirical results over diverse settings and datasets show that our method yields robust performance: Its rankings of expert workers are consistently either superior or at least comparable to those obtained by the best alternative approach. Accordingly, our method constitutes a de facto benchmark for future research on the REQ problem.
Root system architecture, physiological and transcriptional traits of soybean (Glycine max L.) in response to water deficit: A review
Authors: Xiong Rentao , Liu Shuo , Considine Michael J. , Siddique Kadambot H.M. , Lam Hon‐Ming , Chen Yinglong
Published: September 2020

Drought stress is the main limiting factor for global soybean growth and production. Genetic improvement for water and nutrient uptake efficiency is critical to advance tolerance and enable more sustainable and resilient production, underpinning yield growth. The identification of quantitative traits and genes related to water and nutrient uptake will enhance our understanding of the mechanisms of drought tolerance in soybean. This review summarizes drought stress in the context of the physiological traits that enable effective acclimation, with a particular focus on roots. Genes controlling root system architecture play an important role in water and nutrient availability, and therefore important targets for breeding strategies to improve drought tolerance. This review highlights the candidate genes that have been identified as regulators of important root traits and responses to water stress. Progress in our understanding of the function of particular genes, including GmACX1, GmMS and GmPEPCK are discussed in the context of developing a system‐based platform for genetic improvement of drought tolerance in soybean.
Reference site selection protocols for mine site ecosystem restoration
Authors: Hernandez‐Santin Lorna , Rudge Mitchel L. , Bartolo Renee E. , Whiteside Timothy G. , Erskine Peter D.
Published: September 2020

Reference site selection associated with mining and resource development requires a comprehensive approach so that stakeholders can be confident that restoration efforts have appropriate target ecosystems. Here, we present our process to select reference sites, within a savanna ecosystem, which will be used to develop and assess closure criteria and restoration guidelines for Ranger Mine (Northern Territory, Australia). The selection of reference sites followed five steps involving desktop and field methods. We recommend that restoration projects consider inclusion criteria, randomly select sites from areas matching the chosen criteria, conduct preliminary data analysis, estimate and update sampling effort and precision at several points throughout the project, and invite stakeholder feedback and revision of the process as often as required. This detailed reference site approach appears to be the first to demonstrate how to use available data to reduce bias, address sampling effort and site selection quantitatively, involve stakeholders, and provide useful data, which can be used to calibrate ecological restoration outcomes for savanna ecosystems.
Children of immigrants as “brokers” in an era of exclusion
Authors: Delgado Vanessa
Published: September 2020

Today, immigrants and their families live in an era of exclusion. Threats of a southern border wall, increased detentions and deportations, false narratives of Mexicans as “rapists,” attempts to eliminate Deferred Action for Childhood Arrivals, and the implementation of penalties for immigrants who use social services are just some examples of the hostile climate immigrant families face. A growing body of literature suggests that children of immigrants help their parents in their transition to the US society as language, cultural, and legal brokers, which generally refers to when youth translate for and/or share resources with their immigrant kin. In this paper, I review the research on contemporary children of immigrants as “brokers” and how the punitive social context influences the way brokering takes place in immigrant families. I conclude with suggestions for future research in the study of brokering in immigrant families.
The Changing Valuation of Dogs1
Authors: Stoltz Dustin S. , Van Ness Justin , Bjerre Mette Evelyn
Published: September 2020

In recent decades, the United States has witnessed profound changes in the sociocultural valuation of dogs, variously described as humanization, sentimentalization, or sacralization. A broad look at this “sacralization” of dogs in the United States reveals that this changing valuation has altered dogs’ place within economic processes. In particular, these changes parallel Viviana Zelizer’s work on the changing valuation of children a century ago. In this article, we further specify Zelizer’s insights by arguing that these accompanying economic transformations are best understood as shifting of a dogs’ place within budgetary units: from objects for human consumption to fellow actors humans consume with and around.
On Teaching as Activism
Authors: Nopper Tamara K.
Published: September 2020

This essay explores the relationship between teaching and activism by interrogating if teaching in higher education should be considered activism. Through a discussion of my commitment to data literacy and how participatory democracy, as practiced by Black Freedom Movement organizer Ella Baker, informs my pedagogy, I interrogate if activism and academic labor should be conflated. In the process I examine how my assessment is informed by my relationship to activism, the academy, my career trajectory, and racism as part of academic work conditions.
Comparative Study on Spray Auto-Ignition of Di-n-Butyl Ether and Diesel Blends at Engine-Like Conditions
Authors: Guan Yuanhang , Liu Wang , Han Dong
Published: September 2020

Di-n-butyl ether (DBE), a promising lignocellulosic biofuel, has been suggested as a potential alternative fuel for compression ignition engines. In this study, the spray auto-ignition characteristics of diesel/DBE blends were experimentally measured on a constant volume combustion chamber. Time-resolved pressure traces and heat release rates in fuel spray combustion were measured at changed fuel blending fractions, ambient temperatures, and oxygen concentrations. Further, ignition delay and combustion delay that evaluates fuel spray ignition tendency were derived and compared for different test blends. Experimental results indicated that fuel spray ignition tendency is promoted with DBE addition, evidenced by the advanced pressure rise and heat release processes, and the shortened ignition and combustion delays. Peak heat release rates are fuel-dependent at high ambient oxygen concentrations since the relative fractions of the premixed and diffusive burns alter with changed DBE addition. However, as the oxygen concentration drops to 11%, fuel effects on the peak heat release rates become less noticeable. Reduced ambient oxygen concentration effectively extends fuel ignition and combustion delays, and typical two-stage pressure rises and heat releases are observed for all test blends, as the oxygen concentration drops to 11%.
Simulation-Based Mission Mobility Reliability Analysis of Off-Road Ground Vehicles
Authors: Liu Yixuan , Jiang Chen , Mourelatos Zissimos P. , Gorsich David , Jayakumar Paramsothy , Fu Yan , Majcher Monica , Hu Zhen
Published: September 2020

This paper develops a simulation-based mission mobility reliability (MMR) analysis framework to account for uncertainty in mobility prediction of off-road ground vehicles in mission planning. A concept of MMR is first proposed to quantify reliability of a mission path which passes through different types of soils. A single-loop Kriging surrogate modeling method is then employed to overcome the computational challenge in MMR assessment caused by expensive mobility simulations. Built upon the surrogate model-based MMR analysis, a dynamic updating scheme is proposed to update the MMR estimation using online mobility data, during the course of a specific mission and for a particular vehicle. The online dynamic updating of MMR allows us for effective and dynamic decision-making during the mission phase, thus proactively avoid rare events of immobility during the mission. A case study demonstrates the efficacy of the proposed MMR analysis and updating framework.
On the Generalization of Merkin’s Theorem for Circulatory Systems: A Rank Criterion
Authors: Bulatovic Ranislav M. , Udwadia Firdaus E.
Published: September 2020

This paper provides a generalization of the celebrated Merkin theorem. It provides new results on the destabilizing effect of circulatory forces on stable potential systems. Previous results are described and discussed, and the paper uncovers a deeper understanding of the fundamental reason for the destabilization. Instability results in terms of rank conditions that deal with the potential and circulatory matrices that describe the system are obtained, thereby generalizing this remarkable theorem. These new results are compared with those obtained earlier.
Steady Motion of a Slack Belt Drive: Dynamics of a Beam in Frictional Contact With Rotating Pulleys
Authors: Scheidl Jakob , Vetyukov Yury
Published: September 2020

We seek the steady-state motion of a slack two-pulley belt drive with the belt modeled as an elastic, shear-deformable rod. Dynamic effects and gravity induce significant transverse deflections due to the low pre-tension. In analogy to the belt-creep theory, it is assumed that each contact region between the belt and one of the pulleys consists of a single sticking and a single sliding zone. Based on the governing equations of the rod theory, we for the first time derive the corresponding boundary value problem and integrate it numerically. Furthermore, a novel mixed Eulerian–Lagrangian finite element scheme is developed that iteratively seeks the steady-state solution. Finite element solutions are validated against semi-analytic results obtained by numerical integration of the boundary value problem. Parameter studies are conducted to examine solution dependence on the stiffness coefficients and the belt pre-tension.
Scaling Analysis of the Thermal Stress Field Produced by a Moving Point Heat Source in a Thin Plate
Authors: Grams Mitchell R. , Mendez Patricio F.
Published: September 2020

This study presents a scaling analysis of thermally induced stresses and strains produced during welding and additive manufacturing of thin structures such as plates or walls. The order of magnitude scaling (OMS) technique was used to develop an appropriate dimensionless formulation, to obtain asymptotic expressions, and to determine the limits of validity. Nonlinear finite element simulations of welding procedures were performed to validate the asymptotic model; plasticity and temperature dependent materials properties for structural steel, stainless steel, and aluminum were considered. Thermal stresses cause plasticity when the temperature reaches a critical temperature termed the first yield temperature. The model developed is valid when the first yield isotherm is elongated, which is the case for most welding and metal additive manufacturing applications. A rigorous novel expression for the criterion of applicability is presented and utilized for prediction of the width of the plastic zone surrounding a weld or additive manufacturing bead. Extrapolations beyond the region of applicability show a consistent trend, which is captured in the form of a general dimensionless empirical expression. This work establishes the foundation for the estimation of forces and distortions induced by welding or additive manufacturing processes, and also the incorporation of effects of departure from idealizations.
Global Sensitivity Analysis for Patient-Specific Aortic Simulations: The Role of Geometry, Boundary Condition and Large Eddy Simulation Modeling Parameters
Authors: Xu Huijuan , Baroli Davide , Veneziani Alessandro
Published: September 2020

Numerical simulations for computational hemodynamics in clinical settings require a combination of many ingredients, mathematical models, solvers and patient-specific data. The sensitivity of the solutions to these factors may be critical, particularly when we have a partial or noisy knowledge of data. Uncertainty quantification is crucial to assess the reliability of the results. We present here an extensive sensitivity analysis in aortic flow simulations, to quantify the dependence of clinically relevant quantities to the patient-specific geometry and the inflow boundary conditions. Geometry and inflow conditions are generally believed to have a major impact on numerical simulations. We resort to a global sensitivity analysis, (i.e., not restricted to a linearization around a working point), based on polynomial chaos expansion (PCE) and the associated Sobol' indices. We regard the geometry and the inflow conditions as the realization of a parametric stochastic process. To construct a physically consistent stochastic process for the geometry, we use a set of longitudinal-in-time images of a patient with an abdominal aortic aneurysm (AAA) to parametrize geometrical variations. Aortic flow is highly disturbed during systole. This leads to high computational costs, even amplified in a sensitivity analysis -when many simulations are needed. To mitigate this, we consider here a large Eddy simulation (LES) model. Our model depends in particular on a user-defined parameter called filter radius. We borrowed the tools of the global sensitivity analysis to assess the sensitivity of the solution to this parameter too. The targeted quantities of interest (QoI) include: the total kinetic energy (TKE), the time-average wall shear stress (TAWSS), and the oscillatory shear index (OSI). The results show that these indexes are mostly sensitive to the geometry. Also, we find that the sensitivity may be different during different instants of the heartbeat and in different regions of the domain of interest. This analysis helps to assess the reliability of in silico tools for clinical applications.
Changes in regeneration-responsive enhancers shape regenerative capacities in vertebrates
Authors: Wang Wei , Hu Chi-Kuo , Zeng An , Alegre Dana , Hu Deqing , Gotting Kirsten , Ortega Granillo Augusto , Wang Yongfu , Robb Sofia , Schnittker Robert , Zhang Shasha , Alegre Dillon , Li Hua , Ross Eric , Zhang Ning , Brunet Anne , Sánchez Alvarado Alejandro
Published: September 2020

Regulatory elements of fish regeneration

Some animals regenerate extensively, whereas others, such as mammals, do not. The reason behind this difference is not clear. If the genetic mechanisms driving regeneration are evolutionarily conserved, the study of distantly related species that are subjected to different selective pressures could identify distinguishing species-specific and conserved regeneration-responsive mechanisms. Zebrafish and the short-lived African killifish are separated by ∼230 million years of evolutionary distance and, as such, provide a biological context to elucidate molecular mechanisms. Wang
et al.
identify both species-specific and evolutionarily conserved regeneration programs in these fish. They also provide evidence that elements of this program are subjected to evolutionary changes in vertebrate species with limited or no regenerative capacities.

Science
, this issue p.
eaaz3090
A triple-star system with a misaligned and warped circumstellar disk shaped by disk tearing
Authors: Kraus Stefan , Kreplin Alexander , Young Alison K. , Bate Matthew R. , Monnier John D. , Harries Tim J. , Avenhaus Henning , Kluska Jacques , Laws Anna S. E. , Rich Evan A. , Willson Matthew , Aarnio Alicia N. , Adams Fred C. , Andrews Sean M. , Anugu Narsireddy , Bae Jaehan , ten Brummelaar Theo , Calvet Nuria , Curé Michel , Davies Claire L. , Ennis Jacob , Espaillat Catherine , Gardner Tyler , Hartmann Lee , Hinkley Sasha , Labdon Aaron , Lanthermann Cyprien , LeBouquin Jean-Baptiste , Schaefer Gail H. , Setterholm Benjamin R. , Wilner David , Zhu Zhaohuan
Published: September 2020

Ripping up a circumstellar disk

During the process of star formation, a disk of gas and dust forms around the young star, controlling the accretion of more material. Once the star has formed, any leftover material in this circumstellar disk can form planets. If a binary or triple star forms at the center of the disk, theoretical models predict that tidal torques caused by their orbits can rip the disk apart, in a process known as disk tearing. Kraus
et al.
observed the nearby young triple-star system GW Orionis with multiple near-infrared and submillimeter telescopes, using the techniques of interferometry and polarimetry. They found evidence for multiple rings with different orientations and warping of part of the disk, both produced by disk tearing.

Science
, this issue p.
1233
Structure of a human 48
S
translational initiation complex
Authors: Brito Querido Jailson , Sokabe Masaaki , Kraatz Sebastian , Gordiyenko Yuliya , Skehel J. Mark , Fraser Christopher S. , Ramakrishnan V.
Published: September 2020

Finding the start

Eukaryotic translation involves many players in a dynamic and well-orchestrated process. A 43
S
preinitiation complex (PIC) comprises the 40
S
ribosomal subunit; initiation factors, including the eIF3 complex, which is known to play a key role; and the transfer RNA used for translation initiation. The PIC is recruited to the cap-binding complex eIF4F at the 5′ end of messenger RNA (mRNA) to form a 48
S
complex that scans along the mRNA for a start codon. Brito Querido
et al.
determined the structure of a reconstituted human 48
S
complex using cryo–electron microscopy. They found that eIF4F binds to eIF3 near the exit site of the ribosome. This positioning suggests that downstream mRNA is likely pulled through the 40
S
subunit to find the start codon.

Science
, this issue p.
1220
Predicting temperature mortality and selection in natural
Drosophila
populations
Authors: Rezende Enrico L. , Bozinovic Francisco , Szilágyi András , Santos Mauro
Published: September 2020

Accounting for heat burdens

As climate warming becomes more and more apparent and influential, there is an increasing desire to predict its long-term impacts on species. Classically, this has been done by extrapolating lethal limits based on those observed in the laboratory. In the real world, however, organisms do not experience a single high temperature that then returns to a comfortable temperature, but rather a series of high temperatures during the hot season. Rezende
et al.
accounted for these accumulative effects in a dynamic model that accurately predicted empirical patterns in wild fruit fly populations, showing that cumulative effects of warming temperatures can be included in future estimates (see the Perspective by Huey and Kearney).

Science
, this issue p.
1242
; see also p.
1163
Regulation of sleep homeostasis mediator adenosine by basal forebrain glutamatergic neurons
Authors: Peng Wanling , Wu Zhaofa , Song Kun , Zhang Siyu , Li Yulong , Xu Min
Published: September 2020

Sleep and basal forebrain activity

Different patterns of neural activity in the brain control the sleep-wake cycle. However, how this activity contributes to sleep homeostasis remains largely unknown. Adenosine in the basal forebrain is a prominent physiological mediator of sleep homeostasis. Using a newly developed indicator, Peng
et al.
monitored adenosine concentration in the mouse basal forebrain. There was a clear correlation with wake state and REM sleep. Activity-dependent release of adenosine could also be elicited after optogenetic stimulation of basal forebrain glutamatergic, but not cholinergic, neurons. These findings offer new insights into how neuronal activity during wakefulness contributes to sleep pressure through the release of sleep-inducing factors.

Science
, this issue p.
eabb0556
Plants sustain the terrestrial silicon cycle during ecosystem retrogression
Authors: de Tombeur F. , Turner B. L. , Laliberté E. , Lambers H. , Mahy G. , Faucon M.-P. , Zemunik G. , Cornelis J.-T.
Published: September 2020

Terrestrial biogeochemistry of silicon

Silicon is an important element in plant tissues and contributes to structural defenses against herbivores and other stresses. However, the terrestrial biogeochemical cycling of silicon is poorly understood, particularly the relative importance of geochemical and biological mechanisms in its regulation. de Tombeur
et al.
studied this question in 2-million-year chronosequences of soil and vegetation in Western Australia. Sites became progressively more weathered and infertile as they aged, indicating that the silicon cycle shifts from geochemical to biological control as the ecosystem develops (see the Perspective by Carey). They found that foliar silicon concentrations increase continuously during ecosystem development, even though rock-derived silicon is depleted in the older soils. By contrast, other major rock-derived nutrients showed decreasing concentrations in plants. Hence, biological silicon cycling allows plants to maintain concentrations even under conditions of extreme soil infertility.

Science
, this issue p.
1245
; see also p.
1161
Soil age alters the global silicon cycle
Authors: Carey Joanna
Published: September 2020

As rocks undergo prolonged chemical weathering, plants become more important for supplying bioavailable silicon
Stratigraphic correlation chart of Carboniferous–Paleogene rocks of Mexico, adjacent southwestern United States, Central America, and Colombia
Authors: Lawton* Timothy F. , Sierra-Rojas† Maria Isabel , Martens Uwe
Published: September 2020

A comprehensive correlation chart of Pennsylvanian–Eocene stratigraphic units in Mexico, adjoining parts of Arizona, New Mexico, south Texas, and Utah, as well as Guatemala, Belize, Honduras, and Colombia, summarizes existing published data regarding ages of sedimentary strata and some igneous rocks. These data incorporate new age interpretations derived from U-Pb detrital zircon maximum depositional ages and igneous dates that were not available as recently as 2000, and the chart complements previous compilations. Although the tectonic and sedimentary history of Mexico and Central America remains debated, we summarize the tectonosedimentary history in 10 genetic phases, developed primarily on the basis of stratigraphic evidence presented here from Mexico and summarized from published literature. These phases include: (1) Gondwanan continental-margin arc and closure of Rheic Ocean, ca. 344–280 Ma; (2) Permian–Triassic arc magmatism, ca. 273–245 Ma; (3) prerift thermal doming of Pangea and development of Pacific margin submarine fans, ca. 245–202 Ma; (4) Gulf of Mexico rifting and extensional Pacific margin continental arc, ca. 200–167 Ma; (5) salt deposition in the Gulf of Mexico basin, ca. 169–166? Ma; (6) widespread onshore extension and rifting, ca. 160–145 Ma; (7) arc and back-arc extension, and carbonate platform and basin development (ca. 145–116 Ma); (8) carbonate platform and basin development and oceanic-arc collision in Mexico, ca. 116–100 Ma; (9) early development of the Mexican orogen in Mexico and Sevier orogen in the western United States, ca. 100–78 Ma; and (10) late development of the Mexican orogen in Mexico and Laramide orogeny in the southwestern United States, ca. 77–48 Ma.
Supplemental Material: A link between rift-related volcanism and end-Ediacaran extinction? Integrated chemostratigraphy, biostratigraphy, and U-Pb geochronology from Sonora, Mexico
Authors: Hodgin E.B. , Nelson Lyle , al. et
Published: September 2020

Section S1 (detailed methods), Section S2 (tuffaceous horizons in marine carbonates), Tables S1–S3, and Figures S1–S5.
Supplemental Material: Similar Holocene glaciation histories in tropical South America and Africa
Authors: Vickers Anthony , Shakun Jeremy , al. et
Published: September 2020

Figures S1–S5, Tables S1–S4, and model codes.
Achondroplasia Foramen Magnum Score: screening infants for stenosis
Authors: Cheung Moira S , Irving Melita , Cocca Alessandra , Santos Rui , Shaunak Meera , Dougherty Harry , Siddiqui Ata , Gringras Paul , Thompson Dominic
Published: September 2020

Background

Achondroplasia is associated with foramen magnum stenosis (FMS) and significant risk of morbidity and sudden death in infants. A sensitive and reliable method of detecting infants who require decompressive surgery is required. This study aims to describe the incidence and severity of FMS in an unselected, sequential series of infants using a novel MRI score and retrospectively correlate severity with clinical examination and cardiorespiratory sleep (CRS) studies.

Methods

The Achondroplasia Foramen Magnum Score (AFMS) was developed and scores were retrospectively correlated with clinical and CRS data over a 3-year period.

Results

Of 36 infants (M:F, 18:18), 2 (5.6%) did not have FMS (AFMS0); 13 (36.1%) had FMS with preservation of the cerebrospinal fluid (CSF) spaces (AFMS1); 3 (8.3%) had FMS with loss of the CSF space but no spinal cord distortion (AFMS2); 13 (36.1%) had FMS with flattening of the cervical cord without signal change (AFMS3); and 5 (13.9%) had FMS resulting in cervical cord signal change (AFMS4). Mean Total Apnea and Hypopnea Index (TAHI) for AFMS0–4 was 3.4, 6.41, 2.97, 10.5 and 25.8, respectively. Severe TAHI had a specificity of 89% but only a 59% sensitivity for AFMS3–4. Neurological examination was normal in 34/36 (94%) patients. Overall, 9/36 (25%) infants required neurosurgery with minimal surgical complications.

Conclusions

Clinical examination and CRS have a low sensitivity for predicting the effects of foramen stenosis on the spinal cord. Routine screening with MRI using AFMS can aid in detecting early spinal cord changes and has the potential to reduce infant morbidity and mortality.
Personal use of permanent hair dyes and cancer risk and mortality in US women: prospective cohort study
Authors: Zhang Yin , Birmann Brenda M , Han Jiali , Giovannucci Edward L , Speizer Frank E , Stampfer Meir J , Rosner Bernard A , Schernhammer Eva S
Published: September 2020

Objective

To evaluate the associations between personal use of permanent hair dyes and cancer risk and mortality.

Design

Prospective cohort study.

Setting and participants

117 200 women enrolled in the Nurses’ Health Study, an ongoing prospective cohort study of female nurses in the United States. The women were free of cancer at baseline, reported information on personal use of permanent hair dyes, and were followed for 36 years.

Exposure

Status, duration, frequency, and integral use (cumulative dose calculated from duration and frequency) of permanent hair dyes. Age at first use and time since first use of permanent hair dyes.

Main outcome measures

Associations of personal use of permanent hair dyes with risk of overall cancer and specific cancers, and cancer related death. Age and multivariable adjusted hazard ratios and 95% confidence intervals were estimated by using Cox proportional hazard models.

Results

Ever users of permanent hair dyes had no significant increases in risk of solid cancers (n=20 805, excluding non-melanoma skin cancers; hazard ratio 0.98, 95% confidence interval 0.96 to 1.01) or hematopoietic cancers overall (n=1807; 1.00, 0.91 to 1.10) compared with non-users. Additionally, ever users did not have an increased risk of most specific cancers (cutaneous squamous cell carcinoma, bladder cancer, melanoma, estrogen receptor positive breast cancer, progesterone receptor positive breast cancer, hormone receptor positive breast cancer, brain cancer, colorectal cancer, kidney cancer, lung cancer, and most of the major subclasses and histological subtypes of hematopoietic cancer) or cancer related death (n=4860; 0.96, 0.91 to 1.02). Basal cell carcinoma risk was slightly increased for ever users (n=22 560; 1.05, 1.02 to 1.08). Cumulative dose was positively associated with risk of estrogen receptor negative breast cancer, progesterone receptor negative breast cancer, hormone receptor negative breast cancer, and ovarian cancer. An increased risk of Hodgkin lymphoma was observed only for women with naturally dark hair (based on 70 women, 24 with dark hair), and a higher risk of basal cell carcinoma was observed for women with naturally light hair.

Conclusion

No positive association was found between personal use of permanent hair dye and risk of most cancers and cancer related mortality. The increased risk of basal cell carcinoma, breast cancer (estrogen receptor negative, progesterone receptor negative, hormone receptor negative) and ovarian cancer, and the mixed findings in analyses stratified by natural hair color warrant further investigation.
Effect of hospital interventions to improve patient flow on emergency department clinical quality indicators
Authors: Sethi Simon , Boulind Caroline , Reeve Julie , Carney Amanda , Bruijns Stevan
Published: September 2020

Introduction

The Royal College of Emergency Medicine highlights poor flow through hospitals as a major challenge to improving emergency department flow. We describe the effect of several hospital-wide flow interventions on Yeovil District Hospital’s emergency department flow.

Methods

During 2016, a design science research study addressed several areas disproportionally contributing to exit block within Yeovil District Hospital. In this follow-up study, we used a retrospective, before/after design, to describe the effect of these interventions on the ED. We used the Royal College of Emergency Medicine’s clinical quality indicators (4-hour standard, time to decision-maker, 7-day unplanned reattendance, left without being seen, ambulatory patient care and patient experience). Pearson correlation coefficient (r) was used to compare variables. Wilcoxon signed-rank test was used to compare performance before and after the intervention.

Results

Yeovil District Hospital emergency department was attended by 160 373 patients between August 2015 and October 2018. Mean monthly attendance was 4112 (±342) patients, mean age was 43 (±28) years with equal male/female split (49/51%). The 4-hour standard made a recovery from 92% to 97% (p=0.01) that did not correlate with a recovery in national data (r=0.09); this despite rising attendances both at Yeovil and nationally (r=0.75). All clinical quality indicators improved significantly (except unplanned reattendance and patient feedback which improved but not significantly).

Discussion

The positive effect on emergency department clinical quality indicators reveals the beneficial impact of improving in-patient flow. Qualitative research is needed to better understand facilitators and barriers to flow improvement work.
Hypochloraemia is associated with 28-day mortality in patients with septic shock: a retrospective analysis of a multicentre prospective registry
Authors: Lee Min Sung , Shin Tae Gun , Kim Won Young , Jo You Hwan , Hwang Yoon Jung , Choi Sung Hyuk , Lim Taeho , Han Kap Su , Shin JongHwan , Suh Gil Joon , Kim Kyung Su , Kang Gu Hyun
Published: September 2020

Objectives

Hyperchloraemia is associated with poor clinical outcomes in sepsis patients; however, this association is not well studied for hypochloraemia. We investigated the prevalence of chloride imbalance and the association between hypochloraemia and 28-day mortality in ED patients with septic shock.

Methods

A retrospective analysis of data from 11 multicentre EDs in the Republic of Korea prospectively collected from October 2015 to April 2018 was performed. Initial chloride levels were categorised as hypochloraemia, normochloraemia and hyperchloraemia, according to sodium chloride difference adjusted criteria. The primary outcome was 28-day mortality. A multivariate logistic regression model adjusting for age, sex, comorbidities, acid-base state, sepsis-related organ failure assessment (SOFA) score, lactate and albumin level was used to test the association between the three chloride categories and 28-day mortality.

Results

Among 2037 enrolled patients, 394 (19.3%), 1582 (77.7%) and 61 (3.0%) patients had hypochloraemia, normochloraemia and hyperchloraemia, respectively. The unadjusted 28-day mortality rate in patients with hypochloraemia was 27.4% (95% CI, 23.1% to 32.1%), which was higher than in patients with normochloraemia (19.7%; 95% CI, 17.8% to 21.8%). Hypochloraemia was associated with an increase in the risk of 28-day mortality (adjusted OR (aOR), 1.36, 95% CI, 1.00 to 1.83) after adjusting for confounders. However, hyperchloraemia was not associated with 28-day mortality (aOR 1.35, 95% CI, 0.82 to 2.24).

Conclusion

Hypochloraemia was more frequently observed than hyperchloraemia in ED patients with septic shock and it was associated with 28-day mortality.
Immune landscape, evolution, hypoxia-mediated viral mimicry pathways and therapeutic potential in molecular subtypes of pancreatic neuroendocrine tumours
Authors: Young Kate , Lawlor Rita T , Ragulan Chanthirika , Patil Yatish , Mafficini Andrea , Bersani Samantha , Antonello Davide , Mansfield David , Cingarlini Sara , Landoni Luca , Pea Antonio , Luchini Claudio , Piredda Liliana , Kannan Nagarajan , Nyamundanda Gift , Morganstein Daniel , Chau Ian , Wiedenmann Bertram , Milella Michele , Melcher Alan , Cunningham David , Starling Naureen , Scarpa Aldo , Sadanandam Anguraj
Published: September 2020

Objective

A comprehensive analysis of the immune landscape of pancreatic neuroendocrine tumours (PanNETs) was performed according to clinicopathological parameters and previously defined molecular subtypes to identify potential therapeutic vulnerabilities in this disease.

Design

Differential expression analysis of 600 immune-related genes was performed on 207 PanNET samples, comprising a training cohort (n=72) and two validation cohorts (n=135) from multiple transcriptome profiling platforms. Different immune-related and subtype-related phenotypes, cell types and pathways were investigated using different in silico methods and were further validated using spatial multiplex immunofluorescence.

Results

The study identified an immune signature of 132 genes segregating PanNETs (n=207) according to four previously defined molecular subtypes: metastasis-like primary (MLP)-1 and MLP-2, insulinoma-like and intermediate. The MLP-1 subtype (26%–31% samples across three cohorts) was strongly associated with elevated levels of immune-related genes, poor prognosis and a cascade of tumour evolutionary events: larger hypoxic and necroptotic tumours leading to increased damage-associated molecular patterns (viral mimicry), stimulator of interferon gene pathway, T cell-inflamed genes, immune checkpoint targets, and T cell-mediated and M1 macrophage-mediated immune escape mechanisms. Multiplex spatial profiling validated significantly increased macrophages in the MLP-1 subtype.

Conclusion

This study provides novel data on the immune microenvironment of PanNETs and identifies MLP-1 subtype as an immune-high phenotype featuring a broad and robust activation of immune-related genes. This study, with further refinement, paves the way for future precision immunotherapy studies in PanNETs to potentially select a subset of MLP-1 patients who may be more likely to respond.
Firearm ownership and perceived risk of personal firearm injury
Authors: Schleimer Julia P , Wintemute Garen J , Kravitz-Wirtz Nicole
Published: September 2020

Despite evidence that firearm access in the home is a strong risk factor for firearm injury, firearms are owned more often for self-protection than for any other reason. In this cross-sectional study, we describe the association between firearm ownership and perceived risk of personal firearm injury using logistic regressions applied to data from the 2018 California Safety and Well-being Survey. Most respondents (57.7%) reported being very/somewhat worried about gun violence happening to them. Compared with non-owners in households without firearms, firearm owners were 60% (adjusted OR (aOR) 0.40, 95% CI: 0.27 to 0.58) less likely to be worried about gun violence happening to them; non-owners living in homes with firearms were 46% (aOR 0.54, 95% CI: 0.33 to 0.88) less likely. This suggests an underestimation of actuarial risk that conflicts with the available evidence, with important implications for public health messaging.