bluuebunny/crossref_metadata_2025 huggingface dataset:
A dynamic model of facilitation on environmental stress gradients
Authors: Dangles Olivier
Published: March 2019

Theories based on competition for resources in animals and other non‐sessile organisms rarely consider the role of facilitative interactions. Yet these interactions are important for community assembly, especially under stressful environments (e.g. the stress‐gradient hypothesis, SGH). To make an explicit link between species interaction theory and SGH patterns, I used a classic resource competition model promoting coexistence between a beneficiary and its facilitator sharing a common resource along a stress gradient. I compared model outcomes for two fundamentally different mechanisms of facilitation (alleviation of resource versus non‐resource stress), and also tested the effect of a reciprocal cost of facilitation from the beneficiary. I then tested model's biological relevance using experimental data from two tuber moth species (Lepidoptera, Gelechiidae) for which facilitation in resource access was previously established. Simulation outcomes revealed that both the mode of facilitation and the incorporation of facilitation costs affected the shape of the facilitation–stress relationship. These predictions are in line with current SGH observations and experiments on both plants and animals and reconcile the frequently reported variability of this relationship in nature. Moreover, a sensitivity analysis of model's parameters confirmed the robustness of the modelling framework to uncover the mechanisms responsible for observed species interaction–stress patterns. Finally, when parameterized with tuber moth demographic data, model's results corresponded to observed interaction outcomes along resource stress gradients. Overall, having a common model for plants and animals may simplify assumptions in SGH studies, allow contrasting the shapes of different consumer–resource relationships and specifying the conditions that favour one type of interaction outcome over another.
Early detection of electromechanical dysfunction in patients with idiopathic premature ventricular contractions
Authors: Walia Rohit , Chang Shih‐Lin , Lin Yenn‐Jiang , Lo Li‐Wei , Hu Yu Feng , Chao Tze‐Fan , Chung Fa‐Po , Liao Jo‐Nan , Lin Chin‐Yu , Chang Yao‐Ting , Lin Chung‐Hsing , Te Abigail Louise D. , Yamada Shinya , Chen Shih‐Ann , Tsao Hsuan‐Ming
Published: March 2019

Background

Premature ventricular contractions (PVCs) induced by subtle cardiac dysfunction are missed by echocardiography. We evaluated acoustic cardiography for detection of early electromechanical dysfunction in patients with idiopathic PVCs and normal left ventricular ejection fraction (LVEF), and investigated the impact of radiofrequency ablation (RFA) in reversing this adverse effect.

Methods

Eighty‐six patients with PVCs and 33 normal controls having normal LVEF were studied. Fifty PVC patients were in the ablation group and 36 in the nonablation group. %Electromechanical activation time (%EMAT), %left ventricular systolic time (%LVST), third (S3) and fourth heart sound (S4), and systolic dysfunction index (SDI) during sinus rhythm (SR) were measured by acoustic cardiography (Audicor, Inovise Medical, Inc., Beaverton, OR, USA) pre‐ and postablation. In 28 patients, acoustic parameters were compared during SR without PVCs, and SR with single PVC, ≥ 2 PVCs, or ventricular tachycardia over 10‐second Audicor recording in a single patient at different times. Twenty‐four‐hour acoustic cardiographic and acoustic cardiographic Holter recording were used to assess the impact of PVC burden on electromechanical function in 41 patients.

Results

%EMAT, S3, S4, and SDI showed significant worsening in the PVC versus control group. %EMAT and SDI were worsened with increasing PVC number in a 10‐second strip. %EMAT showed significant linear increment with increasing PVC burden. There was a significant improvement in %EMAT, %LVST, S3, S4, and SDI postablation in patients with PVCs.

Conclusion

Acoustic cardiography can detect PVC‐induced minor electromechanical dysfunction in patients with normal LVEF. RFA can reverse this adverse effect.
Association of MHC class II haplotypes with reduced faecal nematode egg count and IgA activity in British Texel sheep
Authors: Ali Alsagher O. A. , Murphy Lisa , Stear Abigail , Fairlie‐Clarke Karen , Nikbakht Brujeni Gholamreza , Donskow‐Łysoniewska Katarzyna , Groth David , Buitkamp Johannes , Stear Michael J.
Published: March 2019

Nematode infection is one of the principal diseases suffered by sheep and the class II region of the MHC has been repeatedly associated with differences in susceptibility and resistance to infection. The aim of this study was to examine the association of MHC class II haplotypes in a flock of Texel sheep with faecal egg counts and antibody responsiveness. Two haplotypes carried the DRB1*11:01 allele which has previously been associated with reduced egg counts in Scottish Blackface and Suffolk sheep. One of the two haplotypes was associated with reduced egg counts in the Texel breed, and both haplotypes were associated with reduced IgA activity against an extract from fourth‐stage larvae. The reduced IgA activity is probably a consequence of reduced numbers of fourth‐stage larvae in sheep carrying the resistance allele. The association of specific MHC alleles with reduced egg counts, reduced worm numbers and decreased IgA activity provides a mechanism for the density‐dependent regulation of parasite growth and fecundity.
Being on the Productivity Frontier: Identifying “Triple Aim Performance” Hospitals
Authors: Roth Aleda , Tucker Anita L. , Venkataraman Sriram , Chilingerian Jon
Published: March 2019

Hospital decision‐makers face trade‐offs that make it difficult to obtain the trifecta of high performance on clinical quality, patient experience, and technical efficiency. We use the term “triple aim performance” (TAP) to refer to the simultaneous achievement of these three goals. Using datasets from 2010 and 2012 and data envelopment analysis, we identify about 20 triple aim performance hospitals in each year among U.S. acute care hospitals with at least 200 beds. We also examine factors that influence the probability of being a TAP hospital. We find that the percentage of physicians employed by the hospital has a positive and significant relationship with TAP, and that bed utilization rate has a positive relationship with technical efficiency, but a negative relationship with clinical quality and patient experience performance.
Love of Land: Nature Protection, Nationalism, and the Struggle over the Establishment of New Communities in Israel
Authors: Dromi Shai M. , Shani Liron
Published: March 2019

Although there is burgeoning research on environmental activism, few studies have examined the interrelationship between nationalism and nature protection in detail. This article examines how groups manage the tension between national commitment and caring for the environment. It focuses on two opposing Israeli activist groups: a settler movement that aims to establish new communities in the fast‐dwindling Israeli open expanses and a “green” movement intent on preserving open spaces. Our observations, interviews, and textual analysis show that both groups believe themselves to be committed to the protection of nature, and that both groups see environmental responsibility as an integral aspect of their Zionist identity. However, the Israeli green movement sees abstaining from interventions in nature and adhering to sustainable development as Zionist because it preserves Israel for future generations. Conversely, the settler movement sees active intervention in nature—by building new communities, planting trees, and hiking—as the proper way to protect Israeli natural expanses and to maintain the livelihood of Israeli society. Our case study demonstrates that, although environmental movements often aspire to universalism, local movements also interlace environmentalism and nationalism in ways that generate multiple (and even contradictory) interpretations of the appropriate way to care for nature.
A class of flat prior distributions for the Poisson‐gamma hierarchical model
Authors: Schmitt Fernando O. , Gilardoni Gustavo L. , Andrade J.A.A.
Published: March 2019

A wide class of prior distributions for the Poisson‐gamma hierarchical model is proposed. Prior distributions in this class carry vague information in the sense that their tails exhibit slow decay. Conditions for the propriety of the resulting posterior density are determined, as well as for the existence of posterior moments of the Poisson rate of either an observed or an unobserved unit.
Evolution of fossil and living spider flies based on morphological and molecular data (Diptera, Acroceridae)
Authors: Gillung Jessica P. , Winterton Shaun L.
Published: March 2019

The phylogeny of spider flies is presented based on an analysis of DNA sequence data combined with morphological characters for both living and fossil species. We sampled 40 extant and extinct genera across all major lineages of Acroceridae, which were compared with outgroup taxa from various lower brachyceran families. In all, 81 morphological characters of 60 extant and 10 extinct ingroup species were combined with 7.1 kb of DNA sequences of two nuclear (CAD and 28S rDNA) and two mitochondrial genes (COI and 16S rDNA). Results strongly support the monophyly of Acroceridae, with major clades contained within classified here in five extant subfamilies (Acrocerinae, Cyrtinae stat. rev., Ogcodinae stat. rev., Panopinae and Philopotinae) and one extinct subfamily, Archocyrtinae. The evolution of important spider fly traits is discussed, including genitalia and wing venation. The status of the enigmatic Psilodera Gray and Pterodontia Gray as members of the Panopinae is confirmed based on both molecular and morphological data.
Determining cooling rates from mica 40Ar/39Ar thermochronology data: Effect of cooling path shape
Authors: McDonald Christopher S. , Warren Clare J. , Hanke Felix , Chard Julian
Published: March 2019

Tectonic models are commonly underpinned by metamorphic cooling rates derived from diffusive‐loss thermochronology data. Such cooling ages are usually linked to temperature via Dodson's closure temperature (TC) formulation, which specifies a 1/time‐shaped cooling path (Contributions to Mineralogy and Petrology, 1973, 40, 259). Geologists, however, commonly discuss cooling rates as a linear temperature/time shape. We present the results of a series of simple finite‐difference diffusion models for Ar diffusion in muscovite and biotite that show that the difference in recorded age between 1/t and linear cooling paths increases significantly with hotter starting temperatures, slower cooling rates and smaller grain sizes. Our results show that it is essential to constrain the cooling path shape in order to make meaningful interpretations of the measured data.
ZmbHLH80 and ZmbHLH90 transcription factors act antagonistically and contribute to regulatePEPC1cell‐specific gene expression in maize
Authors: Górska Alicja M. , Gouveia Paulo , Borba Ana R. , Zimmermann Anna , Serra Tânia S. , Lourenço Tiago F. , Margarida Oliveira Maria , Peterhänsel Christoph , Saibo Nelson J. M.
Published: March 2019

Compartmentation of photosynthetic reactions between mesophyll and bundle sheath cells is a key feature of C4photosynthesis and depends on the cell‐specific accumulation of major C4enzymes, such as phosphoenolpyruvate carboxylase 1. TheZmPEPC1upstream region, which drives light‐inducible and mesophyll‐specific gene expression in maize, has been shown to keep the same properties when introduced into rice (C3plant), indicating that rice has the transcription factors (TFs) needed to confer C4‐like gene expression. Using a yeast one‐hybrid approach, we identified OsbHLH112, a rice basic Helix‐Loop‐Helix (bHLH) TF that interacts with the maizeZmPEPC1upstream region. Moreover, we found that maize OsbHLH112 homologues, ZmbHLH80, and ZmbHLH90, also interact with theZmPEPC1upstream region, suggesting that these C4regulators were co‐opted from C3plants. A transactivation assay in maize mesophyll protoplasts revealed that ZmbHLH80 represses, whereas ZmbHLH90 activates,ZmPEPC1expression. In addition, ZmbHLH80 was shown to impair theZmPEPC1promoter activation caused by ZmbHLH90. We showed that ZmbHLH80 and ZmbHLH90 bind to the samecis‐element within theZmPEPC1upstream region either as homodimers or heterodimers. The formation of homo‐ and heterodimers with higher oligomeric forms promoted by ZmbHLH80 may explain its negative effect on gene transcription. Gene expression analysis revealed thatZmbHLH80is preferentially expressed in bundle sheath cells, whereasZmbHLH90does not show a clear cell‐specific expression pattern. Altogether, our results led us to propose a model in which ZmbHLH80 contributes to mesophyll‐specificZmPEPC1gene expression by impairing ZmbHLH90‐mediatedZmPEPC1activation in the bundle sheath cells.
A novel strip meniscometry method for measuring aqueous tear volume in dogs: Clinical correlations with the Schirmer tear and phenol red thread tests
Authors: Miyasaka Keiichi , Kazama Yoshiyuki , Iwashita Hiroko , Wakaiki Shinsuke , Saito Akihiko
Published: March 2019

Objectives

The strip meniscometry test (SMT) is a novel method for quantitative measurement of tear volume with only five seconds. We aimed to evaluate clinical correlations of SMT with the gold standard Schirmer tear test (STT) and phenol red thread test (PRT) in dogs, including normal and tear‐deficient eyes.

Animals studied

Left eyes from 621 outpatient dogs with and without ocular disorders were evaluated.

Procedures

Each subject underwent SMT, PRT, and STT without topical anesthesia in the described order with five‐minute intervals. The total population was divided into four groups by classifying tear deficiency severity based on STT results: “severe” (0‐5 mm/min), “moderate” (6‐10 mm/min), “subclinical” (11‐14 mm/min), and “normal” (15 or more mm/min).

Results

The strongest correlation coefficient was found between SMT‐STT (0.676), followed by PRT‐STT (0.637) and SMT‐PRT (0.600) pairs. Mean(SD) scores of SMT, PRT, and STT in total population were 9.47 (4.08) mm/5 s, 33.30 (8.52) mm/15 s, and 16.47 (7.01) mm/min. Significant differences were found among STT‐classified groups, both using SMT and PRT results. Receiver operating characteristic (ROC) curves revealed that SMT better agreed with STT than PRT; agreement increased with increasing STT severity. A cutoff for SMT was identified at 10 mm/5 s to discriminate normal eyes from tear‐deficient eyes, yielding high sensitivities and acceptable specificities.

Conclusions

SMT could be superior to PRT for discriminating tear‐deficient eyes. The high sensitivity of SMT could be useful as an initial diagnostic tool to rule out normal eyes with the short testing time.
In Vivo Layer-Specific Mechanical Characterization of Porcine Stomach
Tissue Using a Customized Ultrasound Elastography System
Authors: Dargar Saurabh , Rahul  , Kruger Uwe , De Suvranu
Published: March 2019

This paper presents in vivo mechanical characterization of the muscularis, submucosa, and mucosa of the porcine stomach wall under large deformation loading. This is particularly important for the development of gastrointestinal pathology-specific surgical intervention techniques. The study is based on testing the cardiac and fundic glandular stomach regions using a custom-developed compression ultrasound elastography system. Particular attention has been paid to elucidate the heterogeneity and anisotropy of tissue response. A Fung hyperelastic material model has been used to model the mechanical response of each tissue layer. A univariate analysis comparing the initial shear moduli of the three layers indicates that the muscularis (5.69 ± 4.06 kPa) is the stiffest followed by the submucosa (3.04 ± 3.32 kPa) and the mucosa (0.56 ± 0.28 kPa). The muscularis is found to be strongly distinguishable from the mucosa tissue in the cardiac and fundic regions based on a multivariate discriminant analysis. The cardiac muscularis is observed to be stiffer than the fundic muscularis tissue (shear moduli of 7.96 ± 3.82 kPa versus 3.42 ± 2.96 kPa), more anisotropic (anisotropic parameter of 2.21 ± 0.77 versus 1.41 ± 0.38), and strongly distinguishable from its fundic counterpart. The results are consistent with the tissue morphology and are in accordance with our previous ex vivo tissue study. Finally, a univariate comparison of the in vivo and ex vivo initial shear moduli for each layer shows that the muscularis and submucosa tissues are softer while in vivo, but the mucosa tissue is stiffer while in vivo. The results concerning the mechanical properties highlight the inhomogeneity and anisotropy of multilayer stomach tissue.
Effects of Inlet Swirl on Pressure Side Film Cooling of Neighboring Vane Surface
Authors: Zhang Yang , Li Yifei , Bian Xiutao , Yuan Xin
Published: March 2019

The lean combustion chamber of low NOx emission engines has a short distance between combustion outlet and nozzle guide vanes (NGVs), with strong swirlers located upstream of the turbine inlet to from steady circulation in the combustion region. Although the lean combustion design benefits emission control, it complicates the turbine’s aerodynamics and heat transfer. The strong swirling flow will influence the near-wall flow field where film cooling acts. This research investigates the influence of inlet swirl on the film cooling of cascades. The test cascades are a 1.95 scale model based on the GE-E3 profile, with an inlet Mach number of 0.1 and Reynolds number of 1.48 × 105. Film cooling effectiveness is measured with pressure-sensitive paint (PSP) technology, with nitrogen simulating coolant at a density ratio of near to 1.0. Two neighboring passages are investigated simultaneously, so that pressure and suction side the film cooling effectiveness can be compared. The inlet swirl is produced by a swirler placed upstream, near the inlet, with five positions along the pitchwise direction. These are as follows: blade 1 aligned, passage 1–2 aligned, blade 2 aligned, passage 2–3 aligned and blade 3 aligned. According to the experimental results, the near-hub region is strongly influenced by inlet swirl, where the averaged film cooling effectiveness can differ by up to 12% between the neighboring blades. At the spanwise location Z/Span = 0.7, when the inlet swirl is moved from blade 1 aligned (position 5) to blade 2 aligned (position 3), the film cooling effectiveness in a small area near the endwall can change by up to 100%.
Transient Vibration Analysis Method for Predicting the Transient Behavior of Milling With Variable Spindle Speeds
Authors: Wang Xinzhi , Bi QingZhen , Chen Tao , Zhu Limin , Ding Han
Published: March 2019

Variable spindle speed (VSS) technique is widely adopted for its effective suppression of chatter. However, heavy transient vibrations occur in practical machining operations although the stable machining parameters are selected according to the asymptotic stability analysis methods. In this paper, this problem is addressed through establishing a transient vibration analysis method to predict the transient behavior of VSS milling. Firstly, the discrete dynamical map of VSS milling is constructed, and the response to initial conditions (RTICs) and the response to external forcing (RTEF) can fully describe the general milling dynamics. On this basis, two transient vibration growth phenomena are found and proved that strong transient vibrations are induced by the transient growth of RTIC or RTEF. To fully predict the transient vibration growth phenomenon, the proposed method adopts the transient stability and receptivity analyses to evaluate RTIC and RTEF, respectively. Other than the existing methods, it gives a stability criterion based on both eigenvalues and nonnormal eigenvectors and considers the transient behavior to external excitation. Besides simulations, a real milling test in an existing work and VSS milling experiments are adopted for verification. The results show good agreement with the prediction of the proposed method.
Experimental Study and Model Predictive Control of a Lean-Burn Gasoline Engine Coupled With a Passive Selective Catalytic Reduction System
Authors: Lin Qinghua , Chen Pingen , Prikhodko Vitaly Y.
Published: March 2019

Lean-burn gasoline engines have demonstrated 10–20% engine efficiency gain over stoichiometric engines and are widely considered as a promising technology for meeting the 54.5 miles-per-gallon (mpg) corporate average fuel economy standard by 2025. Nevertheless, nitrogen oxides (NOx) emissions control for lean-burn gasoline for meeting the stringent Environmental Protection Agency tier 3 emission standards has been one of the main challenges toward the commercialization of highly efficient lean-burn gasoline engines in the United States. Passive selective catalytic reduction (SCR) systems, which consist of a three-way catalyst (TWC) and SCR, have demonstrated great potentials of effectively reducing NOx emissions for lean gasoline engines at low cost. However, passive SCR operation may cause significant fuel penalty since rich engine combustion is required for ammonia generation. The purpose of this study is to develop a model-predictive control (MPC) scheme for a lean-burn gasoline engine coupled with a passive SCR system to minimize the total equivalent fuel penalty associated with passive SCR operation while satisfying stringent NOx and ammonia (NH3) emissions requirements. Simulation results demonstrate that the MPC approach can reduce the fuel penalty by 43.9% in a simulated US06 cycle and 28.0% in a simulated urban dynamometer driving schedule (UDDS) cycle, respectively, compared to the baseline control, while achieving over 97% DeNOx efficiency and less than 15 ppm tailpipe ammonia slip. The proposed MPC controller can potentially enable highly efficient lean-burn gasoline engines while meeting the stringent Environmental Protection Agency tier 3 emission standards.
A Unit Cell Design Guideline Development Method for Meso-Scaled Periodic Cellular Material Structures
Authors: Fazelpour Mohammad , Shankar Prabhu , Summers Joshua D.
Published: March 2019

Much research has been conducted on effective elastic properties of meso-scaled periodic cellular material (MPCM) structures; however, there is only limited research providing guidelines on how to develop improved unit cell (UC) topologies and shapes for a given set of loading requirements and conditions. This paper presents guidelines to improve the shear flexibility of the MPCMs while maintaining the effective shear modules by changing the topology or the shape of a unit cell. The guidelines are intended to use design knowledge for helping engineers by providing recommendations at any stage of the design process. In this paper, the guidelines are developed by changing topology characteristics to achieve a desired effective property of the MPCM structure. The effects of individual members, such as side connection, transverse connection, vertical legs, and curved beams of MPCM structure, when subjected to the in-plane shear loading are investigated through conducting a set of numerical simulation on UCs with similar topology and shape characteristics. Based on the simulation results, the unit cell design guidelines are developed to provide recommendations to engineers on improving the shear flexure of MPCM during the design process. Ultimately, a unit cell design guideline development method is offered and demonstrated by developing two new design guidelines.
Brief Analysis of Sounds Using a Smartphone
Authors: Florea Catalin
Published: March 2019

In almost any given day, one will stumble upon sounds that are out of the ordinary, distinct enough to capture one’s attention. Ordinary sounds in a home are represented by the white-noise-like background created by speaking, moving around, household appliances running, and so forth. The out of the ordinary is the sparkling sound of a knife blade or a fork, the clinking of glasses, or dropping of a coin in a bowl. With the help of a smartphone and an app that can provide basic sound analysis, we can identify what makes a given sound to be out of the ordinary and, in the process, learn more about the sounds we hear. It has already been shown, for example, how a smartphone can be used to check resonant frequencies of whistles, or to map a sound field in polar coordinates—to give just a couple of examples. It is our intention in the following to show the wealth of findings when a variety of sounds from around the house are recorded and analyzed using a smartphone and a readily available app.
Plasmon damping depends on the chemical nature of the nanoparticle interface
Authors: Foerster Benjamin , Spata Vincent A. , Carter Emily A. , Sönnichsen Carsten , Link Stephan
Published: March 2019

Damping of gold nanorod plasmons by surface-adsorbed molecules is best explained by scattering off adsorbate-induced dipoles.
Single-molecule polarization microscopy of DNA intercalators sheds light on the structure of S-DNA
Authors: Backer Adam S. , Biebricher Andreas S. , King Graeme A. , Wuite Gijs J. L. , Heller Iddo , Peterman Erwin J. G.
Published: March 2019

Optical tweezers and single-molecule polarization imaging reveal structural features of overstretched DNA.
Remote detection of radioactive material using mid-IR laser–driven electron avalanche
Authors: Schwartz Robert M. , Woodbury Daniel , Isaacs Joshua , Sprangle Phillip , Milchberg Howard M.
Published: March 2019

We show that laser pulses can sensitively detect the presence of a remote radioactive source by sparking its surrounding air.
Cell competition during reprogramming gives rise to dominant clones
Authors: Shakiba Nika , Fahmy Ahmed , Jayakumaran Gowtham , McGibbon Sophie , David Laurent , Trcka Daniel , Elbaz Judith , Puri Mira C. , Nagy Andras , van der Kooy Derek , Goyal Sidhartha , Wrana Jeffrey L. , Zandstra Peter W.
Published: March 2019

Domination in the stem cell world

A Nobel Prize–winning discovery showed that specialized cells can be genetically reprogrammed into stem cells, thus gaining the ability to become any cell type in the body. But what happens during reprogramming is not completely understood. Shakiba
et al.
used experimental and mathematical approaches to show that skin cells compete during reprogramming, eliminating one another as the population progresses toward the stem cell state (see the Perspective by Wolff and Purvis). The “winners” are a special class of skin cells originating from the neural crest. Cells of this type normally emerge during embryonic development and migrate into various tissues, including the skin, muscle, and nervous system.

Science
, this issue p.
eaan0925
; see also p.
330
The Qingjiang biota—A Burgess Shale–type fossil Lagerstätte from the early Cambrian of South China
Authors: Fu Dongjing , Tong Guanghui , Dai Tao , Liu Wei , Yang Yuning , Zhang Yuan , Cui Linhao , Li Luoyang , Yun Hao , Wu Yu , Sun Ao , Liu Cong , Pei Wenrui , Gaines Robert R. , Zhang Xingliang
Published: March 2019

A treasure trove of Cambrian secrets

Animal life exploded in diversity and form during the Cambrian period about 500 million years ago. Fu
et al.
describe an early Cambrian fossil site in China that contains a variety of specimens, more than half of which are previously undescribed (see the Perspective by Daley). The site rivals previously described Cambrian sites, such as the Burgess Shale, and should help to elucidate biological innovation and diversification during this period.

Science
, this issue p.
1338
; see also p.
1284
Factors influencing meiotic recombination revealed by whole-genome sequencing of single sperm
Authors: Hinch Anjali Gupta , Zhang Gang , Becker Philipp W. , Moralli Daniela , Hinch Robert , Davies Benjamin , Bowden Rory , Donnelly Peter
Published: March 2019

Sequencing and the single sperm

During meiosis, homologous chromosomes undergo doublestrand breaks in DNA that can cross over, shuffling genetic material. However, not every double-strand break resolves in a crossover event. Hinch
et al.
wanted to determine the rules governing DNA recombination. They developed a method to sequence individual mouse sperm and applied it to mice carrying two different alleles of a protein involved in mammalian crossovers. A high-resolution genetic map revealed the relationships between the distribution of crossovers, proteins involved in recombination, and specific factors determining whether a double-strand break becomes a crossover.

Science
, this issue p.
eaau8861
EUCAST Susceptibility Testing of Isavuconazole: MIC Data for Contemporary Clinical Mold and Yeast Isolates
Authors: Jørgensen Karin Meinike , Astvad Karen Marie Thyssen , Hare Rasmus Krøger , Arendrup Maiken Cavling
Published: March 2019

Isavuconazole is the newest medical azole. We investigated EUCAST MICs for isavuconazole and seven comparators against 1,498 contemporary isolates (2016 to 2017).
Antifungal Drugs Influence Neutrophil Effector Functions
Authors: Ries Frederic , Alflen Astrid , Aranda Lopez Pamela , Beckert Hendrik , Theobald Matthias , Schild Hansjörg , Teschner Daniel , Radsak Markus Philipp
Published: March 2019

There is a growing body of evidence for immunomodulatory side effects of antifungal agents on different immune cells, e.g., T cells. Therefore, the aim of our study was to clarify these interactions with regard to the effector functions of polymorphonuclear neutrophils (PMN).
A Novel Murine Model Expressing a Chimeric mSCARB2/hSCARB2 Receptor Is Highly Susceptible to Oral Infection with Clinical Isolates of Enterovirus 71
Authors: Yang Cheng-Hung , Liang Chung-Tiang , Jiang Si-Tse , Chen Kuan-Hsing , Yang Chun-Chiao , Cheng Mei-Ling , Ho Hung-Yao
Published: March 2019

The availability of a murine model of EV71 infection is beneficial for the understanding of pathogenic mechanisms and the development and assessment of vaccines and antiviral drugs. However, the lack of a murine oral infection model thwarted the study of pathogenesis induced by clinically relevant EV71 strains that are transmitted via the oral-oral or oral-fecal route. Our Tg mice could be intragastrically infected with clinically relevant EV71 strains in an efficient way and developed neurological symptoms and pathological changes strikingly resembling those of human infection. Moreover, these mice showed an age-dependent change in susceptibility that is similar to the human case. This Tg mouse, when combined with the use of other genetically modified mice, potentially contributes to studying the relationship between developmental changes in immunity and susceptibility to virus.
Group B
Streptococcus
(
Streptococcus agalactiae
)
Authors: Raabe Vanessa N. , Shane Andi L.
Published: March 2019

Invasive disease due to group B
Streptococcus
infection (
Streptococcus agalactiae
) results in a wide spectrum of clinical disease. In North America, serotypes Ia, Ib, II, III, and V are most frequently associated with invasive disease. Group B
Streptococcus
remains a continuing source of morbidity and mortality in high-risk populations, including pregnant women, neonates, and the elderly; an increasing incidence of invasive disease has been observed in nonpregnant adults. Group B
Streptococcus
remains the most common culture-confirmed neonatal bacterial infection in the United States and is a significant source of neonatal morbidity globally. Intrapartum antibiotic prophylaxis has reduced the incidence of early-onset neonatal disease without a notable impact on the incidence of late-onset neonatal disease. Penicillin G remains the mainstay of therapy, although reduced penicillin susceptibility has been observed in select isolates. Increased frequency of resistance to non-beta-lactam antibiotics, including clindamycin, erythromycin, and fluoroquinolones, has been observed, with some isolates demonstrating resistance to vancomycin. The development and implementation of strategies to identify hosts, treat judiciously with antimicrobials with the narrowest spectra, and prevent invasive disease, with vaccines, are essential to reduce the burden of group B
Streptococcus
disease.
Antibiotic Resistance and the MRSA Problem
Authors: Vestergaard Martin , Frees Dorte , Ingmer Hanne
Published: March 2019

Staphylococcus aureus
is capable of becoming resistant to all classes of antibiotics clinically available and resistance can develop through
de novo
mutations in chromosomal genes or through acquisition of horizontally transferred resistance determinants. This review covers the most important antibiotics available for treatment of
S. aureus
infections and a special emphasis is dedicated to the current knowledge of the wide variety of resistance mechanisms that
S. aureus
employ to withstand antibiotics. Since resistance development has been inevitable for all currently available antibiotics, new therapies are continuously under development. Besides development of new small molecules affecting cell viability, alternative approaches including anti-virulence and bacteriophage therapeutics are being investigated and may become important tools to combat staphylococcal infections in the future.
Making research central to good paediatric practice
Authors: Davies Hugh T , Phillips Bob , Preston Jennifer , Stones Simon R
Published: March 2019

There is evidence abroad of a cautious if not protective approach to research involving children and young people (CYP). We are sensitive to these views but believe they are based on a misconception that we must address together. In this introductory article we look at the complexities and risks of this research, how we must involving CYP and their families in the all aspects of research, how to seek valid consent and assent and how research findings should be reported. Considering how we should conduct this ongoing debate, we outline seven principles that we believe should underpin the necessary dialogue between all with legitimate interest. Our debate should be: (1) evidence informed: arguments should be supported by appropriate and reasonably accurate factual claims; (2) transparent about the grounds for decisions; (3) balanced: arguments should be met by contrary arguments; (4) conscientious: we must be willing to talk and listen, with civility and respect; (5) substantive: arguments should be considered sincerely on their merits, not on how they are made or by who is making them; (6) comprehensive: all points of view held by significant portions of the population should receive attention; and (7) with procedures for revising decisions in light of challenges, and it should be our responsibility to ensure we have met all of these.
Image-guided volumetric modulated arc therapy (IG-VMAT) for unresectable ACC of the trachea: a feasible curative option
Authors: Chowdhary Rahul Lal , Chufal Kundan Singh , Pahuja Anjali Kakria , Bhushan Manindra , Singh Rajpal , Ahmad Irfan
Published: March 2019

A middle-aged man presented with progressively worsening breathlessness and non-productive cough for the last 3 months. On examination, his breathing was stridulous and air entry was decreased bilaterally. He underwent emergency fibre-optic bronchoscopy, which revealed a tracheal growth causing luminal narrowing, and after tumour debulking, he improved symptomatically. Histopathological evaluation of the specimen revealed an adenoid cystic carcinoma of the trachea, and systemic evaluation revealed metastatic dissemination. Systemic molecular-targeted therapy was initiated (gefitinib and later imatinib mesylate) and continued for 5 years, in view of stable disease on periodic follow-up. He subsequently presented with breathlessness again, which was managed with an emergency tracheostomy. In view of stable systemic disease and local progression only, he received definitive radiotherapy with image-guided volumetric modulated arc therapy, which resulted in a complete radiological response. The patient has been disease-free for the last 9 months.
Rare presentation of anaphylaxis: pancake syndrome
Authors: Masaki Katsunori , Fukunaga Koichi , Kawakami Yuji , Haque Rubaiyat
Published: March 2019

A 43-year-old woman presented with oral discomfort, sneezing, urticaria, eyelid angioedema, abdominal pain, diarrhoea, dyspnoea and wheeze soon after eating a Japanese flour pancake (okonomiyaki, containing wheat, egg, yam, pork, prawn and squid). Subsequent analysis of the flour used in the pancake revealed the presence ofDermatophagoides farinae(4500 mites/g). The patient tested positive for specific IgE toD. farinae(15.2 kU/L) andD. pteronyssinus(14.0 kU/L) with negative responses to other ingredients in the pancake. Oral ingestion of dust mite in poorly stored foods can cause anaphylactic reactions in patients with allergy.
Harms and benefits of opioids for management of non-surgical acute and chronic low back pain: a systematic review
Authors: Tucker Hannah-Rose , Scaff Katie , McCloud Tess , Carlomagno Kimberly , Daly Kathleen , Garcia Alessandra , Cook Chad E
Published: March 2019

Background

Consequences of prescription opioid use involve harms, addiction, tolerance and death. Despite routine prescription, opioids are not recommended for initial intervention by any major multidisciplinary low back pain (LBP) guideline.

Objective

Our primary purpose was to improve overall understanding of the harms and benefits associated with oral opioid interventions prescribed for treatment of acute or chronic back pain. Our second goal was to evaluate pain intensity and to compare and contrast these data with the harms. Our last objective was to evaluate conflicts of interest among the study authors and the findings.

Design/data/eligibility criteria

Studies incorporating oral prescription opioid management of non-surgical LBP were evaluated. After systematic assessment, no studies that met inclusion included participants with specifically acute LBP. Therefore, extracted data reflects only populations with subacute and chronic LBP. Data on reported harms, severe harms, pain outcomes and withdrawal rates were extracted and meta-analyses were completed for opioid versus placebo trials and opioids versus non-opioid trials.

Results

Fourteen studies met inclusion/exclusion requirements. All trials involved short-term management with limited follow-up. A high percentage of harms were identified across most studies. Opioids were not shown to be superior to other medications, and only showed superiority to placebo comparators (at cost of additional harms).

Conclusion

This review identified trends of higher harms rates and higher percentages of severe harms in opioid arms for the management of subacute and chronic LBP. The majority of trials that demonstrated benefits with opioids also had potential conflicts of interest. Lastly, non-opioid medications demonstrated statistically significant pain improvement compared with opioids. We feel that the results of the trial are supportive of current LBP guidelines and do not condone the initial use of opioids in management of subacute or chronic LBP.

Trial registration number

CRD42017070914
Ultrasound therapy reduces persistent post-thoracotomy tactile allodynia and spinal substance P expression in rats
Authors: Lin Heng-Teng , Chiu Chong-Chi , Liu Chen-Chih , Chen Yu-Wen , Wang Jhi-Joung , Hung Ching-Hsia
Published: March 2019

Background

Therapeutic ultrasound (TU) alleviates nerve injury-associated pain, while the molecular mechanisms are less clear. This is an investigator-initiated experimental study to evaluate the mechanisms and effects of ultrasound on prolonged post-thoracotomy pain in a rodent model.

Methods

The rats were randomly separated into four groups (n=8 per group): sham-operation (sham; group 1), thoracotomy and rib retraction (TRR; group 2), and TRR procedure followed by TU (TRR+TU-3; group 3) or TU with the ultrasound power turned off (TRR+TU-0; group 4). TU was delivered daily, beginning on postoperative day 11 (POD 11) for the next 2 weeks. Mechanical sensitivity, subcutaneous tissue temperature, and spinal substance P and interleukin-1 beta (IL-1β) were evaluated on PODs 11 and 23.

Results

Group 3, which received ultrasound treatment (3 MHz; 1.0 W/cm
2
) for 5 min each day, demonstrated higher mechanical withdrawal thresholds when compared with the group without ultrasound intervention (group 2) or sham ultrasound (group 4). Ultrasound treatment also inhibited the upregulation of spinal substance P and IL-1β measured from spinal cord dorsal horns extract and increased subcutaneous temperature.

Conclusions

The results of this study suggest an increase in mechanical withdrawal thresholds and subcutaneous temperature, as well as a downregulation of spinal substance P and IL-1β, in the group which received ultrasound treatment. The regulation of spinal substance P and IL-1β may mediate potential effects of this non-invasive treatment.
Is the common teasel (Dipsacus fullonum) carnivorous or was Francis Darwin wrong?
Authors: Krupa James J. , Thomas J. Matthew
Published: March 2019

Francis Darwin first suggested that the common teasel (Dipsacus fullonum L.), a biennial species, might be a carnivorous plant. He suggested that this species acquires nutrients from insects that drown in water-holding cups formed at the base of leaves that surround the stems. Since then, other biologists have made the same claim. To test this we addressed the question: does adding invertebrates as supplemental nutrients to water-filled cups of D. fullonum influence reproduction or are nutrients only obtained from the soil? We performed two factorial designed experiments (high-nutrient soil vs. low-nutrient soil) × (fed vs. control) to test this. Fed treatments involved either crickets or liquefied animal solution. We performed a third experiment where teasel plants were grown in nutrient deficient standard carnivorous plant soil mix to determine whether prey supplement influenced growth and reproduction. These experiments revealed that soil nutrients alone influence growth and reproduction. More seeds were produced by plants grown in high-nutrient soil; while curiously, a higher percentage of seeds germinated from plants grown in low-nutrient soil. When teasel rosettes were grown in carnivorous plant soil, plants did not grow, produce stems, or flower, even with animal solution. Thus we found no evidence suggesting common teasel is carnivorous.
Wormhole solutions in Rastall gravity theory
Authors: Halder Shibaji , Bhattacharya Subhra , Chakraborty Subenoy
Published: March 2019

This work looks for new wormhole solutions in the non-conservative Rastall gravity. Although Rastall gravity is considered to be a higher-dimensional gravity, the actual diversion from general relativity essentially happens due to a modification in the corresponding matter tensor part. Thus, it would be interesting to find out if such non-minimal coupling has any effect on the traversable wormholes and their corresponding energy conditions.
Rational solutions to two Sawada–Kotera-like equations
Authors: Du Ya-Hong , Yun Yin-Shan , Ma Wen-Xiu
Published: March 2019

Two Sawada–Kotera-like equations are introduced by the generalized bilinear operators [Formula: see text] associated with two prime numbers [Formula: see text] and [Formula: see text], respectively. Rational solutions of the two presented Sawada–Kotera-like equations are generated by searching polynomial solutions of the corresponding two generalized bilinear equations.
Strong coupling between two plasmonic cavities based on metal–insulator–metal structure
Authors: Shang Jun-Shu , Song Gang , Yan Jie-Yun , Yu Li
Published: March 2019

We investigate the strong coupling phenomenon between a circular cavity and a rectangular cavity based on a metal–insulator–metal (MIM) structure. Finite difference time domain method is employed to well describe the strong coupling phenomenon and the simulation results show that two splitting peaks are observed in our proposed structure, while only one resonant peak is found in MIM structure involving only a circular cavity. The coupling between the circular cavity and the rectangular cavity is manipulated by the geometry of the cavities and the symmetry of the whole structure. An asymmetric lineshape of the transmission spectrum is observed with a narrow linewidth and a deep valley, which has potential applications in plasmon sensor.
Lump solutions of a new generalized Kadomtsev–Petviashvili equation
Authors: Yu Jing , Ma Wen-Xiu , Chen Shou-Ting
Published: March 2019

A new generalized Kadomtsev–Petviashvili (GKP) equation is derived from a bilinear differential equation by taking the transformation [Formula: see text]. By symbolic computation with Maple, lump solutions, rationally localized in all directions in the space, to the GKP equation are presented. The obtained lump solutions contain a set of six free parameters, four of which should satisfy a nonzero determinant condition. As special examples, six particular lump solutions are constructed and depicted with [Formula: see text].
Periodic stochastic high-order Degasperis–Procesi equation with cylindrical fBm
Authors: Chen Yong , Gao Hongjun , Huang Jianhua
Published: March 2019

This paper studies the periodic stochastic high-order Degasperis–Procesi (DP) equation driven by a cylindrical fractional Brownian motion (fBm) which is white in space. And it has the covariance with Hurst parameter [Formula: see text] in the time variable. The local existence and uniqueness of the solution [Formula: see text] in [Formula: see text] with [Formula: see text] are proved by fixed point theorem combined with the stochastic term estimations in the Besov-type Bourgain space [Formula: see text] and the second iteration of non-linear term.
Random exponential attractor for second-order nonautonomous stochastic lattice systems with multiplicative white noise
Authors: Su Haijuan , Zhou Shengfan , Wu Luyao
Published: March 2019

We studied the existence of a random exponential attractor in the weighted space of infinite sequences for second-order nonautonomous stochastic lattice system with linear multiplicative white noise. Firstly, we present some sufficient conditions for the existence of a random exponential attractor for a continuous cocycle defined on a weighted space of infinite sequences. Secondly, we transferred the second-order stochastic lattice system with multiplicative white noise into a random lattice system without noise through the Ornstein–Uhlenbeck process, whose solutions generate a continuous cocycle on a weighted space of infinite sequences. Thirdly, we estimated the bound and tail of solutions for the random system. Fourthly, we verified the Lipschitz continuity of the continuous cocycle and decomposed the difference between two solutions into a sum of two parts, and carefully estimated the bound of the norm of each part and the expectations of some random variables. Finally, we obtained the existence of a random exponential attractor for the considered system.
Revealing millimetre-scale ground movements in London using SqueeSAR™
Authors: Bischoff Christine Anna , Ghail Richard C. , Mason Philippa J. , Ferretti Alessandro , Davis John A.
Published: March 2019

A series of illustrated examples is presented here to demonstrate the capabilities of ground-level monitoring using InSAR (interferometric synthetic aperture radar). Greater London is an ideal area to demonstrate and validate measurements derived using InSAR; its continuous urban fabric and the regular acquisition of SAR images from high-resolution sensors, such as TerraSAR-X, allows detection and monitoring of over 1.7 million measurement points with millimetre-scale accuracy. The results, some of which are shown here, reveal fascinating spatial and temporal patterns of ground motion across London and demonstrate the benefit of using high-resolution InSAR technologies in engineering applications. Interpreting the motion patterns can be challenging, however, owing to their complex and sometimes mysterious causes; we therefore welcome any assistance in doing so and we hope this photographic feature serves to trigger interest.

Thematic collection:
This article is part of the Measurement and monitoring collection available at:
https://www.lyellcollection.org/cc/measurement-and-monitoring