bluuebunny/crossref_metadata_2025 huggingface dataset:
Russulaceae: a new genomic dataset to study ecosystem function and evolutionary diversification of ectomycorrhizal fungi with their tree associates
Authors: Looney Brian P. , Meidl Peter , Piatek Marek J. , Miettinen Otto , Martin Francis M. , Matheny P. Brandon , Labbé Jessy L.
Published: January 2018

The family Russulaceae is considered an iconic lineage of mostly mushroom‐forming basidiomycetes due to their importance as edible mushrooms in many parts of the world, and their ubiquity as ectomycorrhizal symbionts in both temperate and tropical forested biomes. Although much research has been focused on this group, a comprehensive or cohesive synthesis by which to understand the functional diversity of the group has yet to develop. Interest in ectomycorrhizal fungi, of which Russulaceae is a key lineage, is prodigious due to the important roles they play as plant root mutualists in ecosystem functioning, global carbon sequestration, and a potential role in technology development toward environmental sustainability. As one of the most species‐diverse ectomycorrhizal lineages, the Russulaceae has recently been the focus of a dense sampling and genome sequencing initiative with the Joint Genome Institute aimed at untangling their functional roles and testing whether functional niche specialization exists for independent lineages of ectomycorrhizal fungi. Here we present a review of important studies on this group to contextualize what we know about its members' evolutionary history and ecosystem functions, as well as to generate hypotheses establishing the Russulaceae as a valuable experimental system.
Therapeutic strategies for congenital myasthenic syndromes
Authors: Lee Manon , Beeson David , Palace Jacqueline
Published: January 2018

To date, more than 25 genes have been implicated in the etiology of the congenital myasthenic syndromes (CMS), and an ever‐growing phenotypic landscape is now encountered in the CMS clinic. Unlike the autoimmune form of myasthenia, there is no role for immunomodulatory agents in the treatment of CMS. The present‐day drug repertoire comprises acetylcholinesterase inhibitors (mainly pyridostigmine), 3,4‐diaminopyridine (3,4‐DAP), ephedrine, salbutamol/albuterol, open‐channel blockers (fluoxetine, quinidine), or a combination of these. These are prescribed by the specialist in an off‐label manner, as there is no drug currently licensed for the treatment of these rare diseases. The effective pharmacological agent varies according to the genetic form of CMS, and it is important to realize that an agent that provides benefit in one CMS subtype can be harmful in another. In addition, the time to treatment response is variable and tends to be commensurate with the drug used. Here, we summarize for the clinician the therapeutic strategies employed in this ever‐evolving disease spectrum. We also address the barriers to treatment and discuss the treatment of CMS in pregnancy.
Analysing the impact of myopia on the Stiles‐Crawford effect of the first kind using a digital micromirror device
Authors: Carmichael Martins Alessandra , Vohnsen Brian
Published: January 2018

Purpose

Photoreceptor light acceptance is closely tied to the Stiles‐Crawford effect of the first kind (SCE‐I). Whether the SCE‐I plays a role in myopic development remains unclear although a reduction in directionality has been predicted for high myopia. The purpose of this study is to analyse the relationship between foveal SCE‐I directionality, axial eye length, and defocus for emmetropic subjects wearing ophthalmic trial lenses during psychophysical measurements and for myopic subjects with their natural correction.

Method

A novel uniaxial flicker system has been implemented making use of a Digital Micromirror Device (DMD) to flicker between a 2.3 visual degrees circular reference and a set of circular test patterns in a monocular Maxwellian view at 0.5 Hz. The brightness of the test is adjusted by the duty cycle of the projected light to an upper limit of 22 727 Hz. The wavelength and bandwidth are set by a tuneable liquid‐crystal filter centred at 550 nm. A total of four measurement series for 11 pupil entrance points have been realized for the right eye of 6 emmetropic and 10 myopic subjects whose pupils were dilated with tropicamide. Five of the emmetropic subjects wore ophthalmic trial lenses in the range of −3 to +9 dioptres to mimic hyperopic to highly myopic vision and resulting visibility plots have been fitted to a Gaussian SCE‐I function. In turn, the myopic subjects wore their natural correction during the analysis of the SCE‐I. All subjects had their axial eye length determined with an ultrasound device.

Results

A SCE‐I directionality parameter in the range of 0.03 to 0.06/mm2 was found for the emmetropic subjects with corrected vision in fair agreement to values in the literature. The results also revealed a marked reduction in directionality in the range from 16% to 30% with every 3 dioptre increase of simulated myopia, as well as a 10% increased directionality in simulated hyperopic eyes. For both emmetropic and myopic subjects, a decrease in directionality with increase in axial length was found in agreement with theoretical expectations.

Conclusion

The study confirms a clear link between SCE‐I directionality, uncorrected defocus, and axial eye length. This may play a role for emmetropization and thus myopic progression as cone photoreceptors capture light from a wider pupil area in elongated eyes due to a geometrical scaling.
Foveal vision power errors induced by spectacle lenses designed to correct peripheral refractive errors
Authors: Barbero Sergio , Faria‐Ribeiro Miguel
Published: January 2018

Purpose

Radial Refractive Gradient (RRG) spectacles are lenses specifically designed to minimize peripheral hyperopic defocus typically found in conventional spectacles. Our goals were: (1) to demonstrate a method to design such lenses; and (2) to quantify the exact foveal vision power errors induced by them.

Methods

The design procedure was based on a point‐by‐point sequential surface construction algorithm that designs a front aspheric surface (back surface is spherical) to achieve a given overall tangential focal length of the lens. A peripheral refraction model was built based on average peripheral refractive errors from a set of eyes. We designed four negative lenses with optical powers: −2.5, −5.0, −7.5 and −10.0 D, so that the tangential focal length of the lens matches the retinal conjugate surface.

Results

The lenses induce very small sagittal power errors in a wide range of off‐axis field angles (30°), solving the problem of peripheral hyperopic defocus. However, such designs introduce non‐negligible mean power errors (above 0.25 D from 7°, 6.8°, 7.1° and 7.8° for the −2.5, −5.0, −7.5 and −10.0 D lenses, respectively) for foveal vision in a rotating eye.

Conclusion

Our results show the unavoidable errors introduced by RRG spectacles when used for dynamic foveal vision. The described method offers valuable information towards determining the best trade‐off between controlling power errors for peripheral and foveal vision.
The role of imprinting on the adoption of diversity management in German universities
Authors: Oertel Simon
Published: January 2018

This study questions the universal effect of organizational imprinting and argues that the relevance of the imprint differs across organizations' administrative levels. Specifically, this study analyses how institutional founding conditions affect the adoption of diversity management, as a method of responding to increasing institutional pressure to conform to a logic of inclusion and equality in institutions of higher education. Focusing on 112 universities in Germany, results show that the imprint does not affect the adoption of diversity management in general but does so at higher administrative levels. Through a discussion of these findings, this study contributes to a more comprehensive understanding of how imprinting affects organizations. Further, it contributes to a better understanding of factors that influence the diffusion of diversity management in universities.
Phosphorus concentration coordinates a respiratory bypass, synthesis and exudation of citrate, and the expression of high‐affinity phosphorus transporters in Solanum lycopersicum
Authors: Del‐Saz Néstor Fernández , Romero‐Munar Antonia , Cawthray Gregory R. , Palma Francisco , Aroca Ricardo , Baraza Elena , Florez‐Sarasa Igor , Lambers Hans , Ribas‐Carbó Miquel
Published: January 2018

Plants exhibit respiratory bypasses (e.g., the alternative oxidase [AOX]) and increase the synthesis of carboxylates in their organs (leaves and roots) in response to phosphorus (P) deficiency, which increases P uptake capacity. They also show differential expression of high‐affinity inorganic phosphorus (Pi) transporters, thus avoiding P toxicity at a high P availability.

The association between AOX and carboxylate synthesis was tested in Solanum lycopersicum plants grown at different soil P availability, by using plants grown under P‐sufficient and P‐limiting conditions and by applying a short‐term (24 hr) P‐sufficient pulse to plants grown under P limitation. Tests were also performed with plants colonized with arbuscular mycorrhizal fungi, which increased plant P concentration under reduced P availability. The in vivo activities of AOX and cytochrome oxidase were measured together with the concentration of carboxylates and the P concentration in plant organs. Gene transcription of Pi transporters (LePT1 and LePT2) was also studied. A coordinated response between plant P concentration with these traits was observed, indicating that a sufficient P availability in soil led to a suppression of both AOX activity and synthesis of citrate and a downregulation of the transcription of genes encoding high‐affinity Pi transporters, presumably to avoid P toxicity.
Is there an optimal organ acceptance rate for pediatric heart transplantation: “A sweet spot”?
Authors: Park Chun Soo , Villa Chet R. , Lorts Angela , Chin Clifford , Tweddell James S. , Zafar Farhan , Morales David L. S.
Published: January 2018

Despite a limited supply of donors, potential donor hearts are often declined for subjective concerns regarding organ quality. This analysis will investigate the relationship between donor heart AR and patient outcome at pediatric transplant centers. The UNOS database was used to identify all match runs for pediatric candidates (age < 18 years) from 2008 through March 2015 in which a heart offer was ultimately placed. Centers which received ≥10 offers/y were included (10 634 offers, 38 centers). Transplant centers were stratified based on their AR: low (<20%, n = 13), medium (20%‐40%, n = 16), or high (>40%, n = 9). Low AR centers experienced worse negative WL outcome compared with medium (P = .022) and high (P = .004) AR centers. Low AR centers had similar post‐transplant graft survival to medium (P = .311) or high (P = .393) AR centers; however, medium AR centers had better post‐transplant graft survival than high AR centers (P = .037). E‐F survival from listing regardless of transplant was worse for low AR centers compared with medium (P < .001) or high (P = .001) AR centers. Low AR centers experience worse WL outcomes without improvement in post‐transplant outcomes. High AR centers experience higher post‐transplant graft failure than medium AR centers. AR of 20%‐40% appears to have optimal WL and post‐transplant outcomes.
Did parents have it right all along? Parents, risk, and living kidney donation: Revisiting the arguments for and against parental living donation of kidneys
Authors: Freeman M. A. , Wightman A. G.
Published: January 2018

Historically, living kidney donation has been justified in part by our belief that living donors face minimal risks of subsequent disease. Recent research has brought that presumption into question, particularly for younger donors including parents. In light of this finding, we re‐examine many of the traditional arguments both for and against the practice of parental living kidney donation. We then propose an alternative framework in which the burden of having a child with end‐stage kidney disease can be considered as an illness experienced by the potential donor parent. We believe this allows a more straightforward, as well as more accurate, assessment of the risks and benefits of donation for the potential parental donor. This assessment might then be used to best inform the decision whether or not to proceed with kidney donation using a shared decision‐making model, while reflecting the appropriate ethical roles of both the potential donor and the transplantation program.
Trends in pediatric liver transplant donors and deceased donor circumstance of death in the United States, 2002‐2015
Authors: Yoeli Dor , Goss Matthew , Galván Nhu. Thao N. , Desai Moreshwar S. , Miloh Tamir A. , Rana Abbas
Published: January 2018

While much of the discussion regarding expanding the donor pool for pediatric liver transplantation has surrounded the use of technical variant grafts, little attention has been directed toward changes in the deceased donor population. The aim of this study was to investigate trends in the circumstance of the death of deceased donors used for pediatric liver transplantation. All pediatric liver transplant recipients transplanted between 2002 and 2015 were identified in the UNOS database and were categorized based on the donor circumstance of death. There was no significant correlation between year of transplantation and number of pediatric liver transplants performed, pediatric donors, split livers, or living donors. There was a significant downward trend in donors from motor vehicle fatalities and an upward trend in suicide, non‐MVA, and death due to natural causes. There was also an upward trend in drowning, one of the most common mechanisms of death among non‐MVA in 2015. While the number of donors who died in MVA has fallen, the number of deceased donors who died from suicide, natural causes, and non‐MVA, especially drowning, has increased, maintaining the overall number of pediatric deceased donor livers transplanted.
Influence of visible light on cutaneous hyperchromias: Clinical efficacy of broad‐spectrum sunscreens
Authors: Martini Ana Paula M. , Maia Campos Patricia M. B. G.
Published: January 2018

Introduction

Cutaneous hyperchromias are disorders of skin pigmentation involving increased melanin production and its irregular accumulation in skin cells. The use of sunscreens is fundamental for the control of hyperchromias by reducing the stimulation of pigmentation, as melanin synthesis is mainly stimulated by solar radiation. Many studies have demonstrated that visible light can induce significant skin damage. Considering the effects of visible light, effective photoprotection should not be limited only to UV protection but should also involve visible and infrared protection.

Objective

The aim of this study was to evaluate the efficacy of UV‐VIS sunscreens in protecting skin against damages caused by solar radiation and the influence of visible light on the appearance of cutaneous hyperchromias.

Methods

Forty volunteers aged 18 to 39 years with skin hyperpigmentation participated in the study. To evaluate the efficacy of the formulations developed, the percentage of hyperpigmented area was evaluated using high‐resolution images—Visioface® Quick (Courage‐Khazaka, Germany) and the analysis of epidermal pigmentation was performed by RCM—Vivascope® 1500 (Lucid, USA). Also, the melanin index was determined using the Mexameter® M X16 colorimeter (Courage‐Khazaka, Germany).

Results

The developed formulations were effective in the reduction in melanin index, epidermal pigmentation, and percentage of hyperpigmented area.

Conclusion

Finally, this study discusses how the combination of UV filters and pigments can protect the skin from solar radiation and reduces skin hyperpigmentations.
Zinc treatment of hydroponically grown barley plants causes a reduction in root and cell hydraulic conductivity and isoform‐dependent decrease in aquaporin gene expression
Authors: Gitto Aurora , Fricke Wieland
Published: January 2018

The cellular and molecular basis of a reduction in root water uptake in plants exposed to heavy metals such as zinc (Zn) is poorly studied. The aim of the present study on hydroponically grown barley (Hordeum vulgare) was to test whether any reduction in root hydraulic conductivity (Lp) in response to Zn treatment is accompanied by a reduction in cell Lp and gene expression level of aquaporin (AQP) isoforms. Plants were grown in the presence of 0.25 μM, (control), 0.1 and 1 mM Zn in the root medium and analysed when they were 16–18 days old. Root and cell Lp was determined through exudation and cell pressure probe analyses, respectively, and gene expression of five candidate AQPs was analysed [real time quantitative polymerase chain reaction (PCR)]. Zinc treatments caused significant reductions (25–83%) in transpiration rate, root and shoot fresh weight, surface area and stomatal conductance. Zinc concentrations in tissues increased more than 100‐fold. Root Lp decreased by 24% (0.1 mM Zn) and 58% (1 mM Zn), while cell Lp decreased by 45 and 71%, respectively. Gene expression of AQPs decreased by 14–80%; decreases were statistically significant for HvPIP1;3, HvPIP2;4 and HvPIP2;5. Turgor in root cortex cells was not reduced by Zn treatments. It is concluded that reductions in plant water flow in response to Zn treatment are facilitated through decreases in root (Lp) and shoot (stomata) hydraulics. The decrease in root Lp is facilitated through reductions in cell Lp and AQP gene expression and may also reflect increased suberization in the endodermis.
The Law: Presidential Signing Statements and Coordinate Constitutional Interpretation
Authors: Rush Mark
Published: January 2018

Zivotofsky v. Kerry (2015) highlighted the constitutional tension surrounding the use of executive signing statements, especially with regard to the president's power to conduct foreign affairs. Critics contend that signing statements come perilously close to having the effect of line‐item vetoes, which the Supreme Court declared unconstitutional in Clinton v. City of New York. I suggest that signing statements are simply written manifestations of practices that naturally occur in a system of checks and balances and in a system where executive branch officials may and must interpret the text of legislation. While signing statements may raise the specter of a president who ignores the express will of Congress, this also is a manifestation of the workings of a constitutional system in which Congress and the president share lawmaking power.
Reintroducing a keystone burrowing rodent to restore an arid North American grassland: challenges and successes
Authors: Davidson Ana D. , Hunter Elizabeth A. , Erz Jon , Lightfoot David C. , McCarthy Aliya M. , Mueller Jennifer K. , Shoemaker Kevin T.
Published: January 2018

Prairie dogs (Cynomys spp.) are important ecosystem engineers in North America's central grasslands, and are a key prey base for numerous predators. Prairie dogs have declined dramatically across their former range, prompting reintroduction efforts to restore their populations and ecosystem functions, but the success of these reintroductions is rarely monitored rigorously. Here, we reintroduced 2,400 Gunnison's prairie dogs (C. gunnisoni) over a period of 6 years to the Sevilleta National Wildlife Refuge, in central New Mexico, U.S.A., a semi‐arid grassland ecosystem at the southern edge of their range. We evaluated the population dynamics of prairie dogs following their reintroduction, and their consequent effects on grassland vertebrates. We found postrelease survival of prairie dogs stabilized at levels typical for the species (ca. 50%) after approximately 1 month, while average annual recruitment was ca. 0.35 juveniles per female, well below what was required for a self‐sustaining, stable population. Extreme drought conditions during much of the study period may have contributed to low recruitment. However, recruitment increased steadily over time, indicating that the reintroduced colony may simply need more time to establish in this arid system. We also found well‐known associates of prairie dog colonies, such as American badgers (Taxidea taxus) and burrowing owls (Athene cunicularia), were significantly more common on the colonies than off. After 7 years, we have yet to meet our goal of establishing a self‐sustaining population of Gunnison's prairie dogs in this semi‐arid grassland. But despite the uncertainty and challenges, our work shows that reestablishing keystone species can promote ecosystem restoration.
God, Party, and the Poor: How Politics and Religion Interact to Affect Economic Justice Attitudes
Authors: Thomson Robert A. , Froese Paul
Published: January 2018

Moral attitudes justifying economic inequality are often embedded within conservative religion and politics in the United States, even as traditional Christian values assert the need for compassion toward the poor. Using the Baylor Religion Survey, we assessed the role of religion in influencing partisan attitudes about poverty, finding that Republicans not only oppose federal policy aimed toward redistribution of wealth but also articulate less of a personal moral obligation to help the poor. However, Republicans who believe in a highly engaged God are strikingly similar to Democrats on these economic justice issues, suggesting that some types of religion do make conservatives more “compassionate.”
Safety and efficacy of foscarnet for the management of ganciclovir‐resistant or refractory cytomegalovirus infections: A single‐center study
Authors: Pierce Brett , Richardson Chad L. , Lacloche Lisa , Allen Anne , Ison Michael G.
Published: January 2018

Background

Infection with cytomegalovirus (CMV) is an important cause of morbidity and mortality following solid organ transplantation. Resistance to ganciclovir can rarely develop via mutations in UL97 or UL54. There are limited published studies assessing the safety and efficacy of foscarnet for the management of ganciclovir‐resistant or refractory cytomegalovirus infection and many centers are reluctant to utilize this important therapy because of concerns about toxicity.

Methods

Solid organ recipients transplanted between January 1, 2006 and December 31, 2014 who received at least 1 dose of foscarnet were retrospectively reviewed to assess treatment outcomes, tolerability, and safety of foscarnet.

Results

Ten of 31 (32.3%) patients who received foscarnet during the study period died during treatment with foscarnet, whereas all 21 surviving recipients successfully cleared infection. Of these surviving patients, 3 (14.3%) developed significant renal dysfunction, defined as >25% decline in estimated glomerular filtration rate during treatment; one‐third had definitive renal biopsy results consistent with foscarnet‐induced toxicity.

Conclusion

Although mortality was high in this population, foscarnet use, with proper precautions, was generally safe and significant renal dysfunction was lower than previously reported in other sources, even with extended use.
Network geometry of evidence from randomised controlled trials addressing donor selection and source of haematopoietic progenitor cells used in allogeneic transplantation: a systematic scoping review
Authors: Monaghan M. , Rizk M. , Pilon S. , Iyengar A. , Shorr R. , Tay J. , Maze D. , Bredeson C. , Hutton B. , Allan D. S.
Published: January 2018

Background and Methods

A scoping review of randomised controlled trials (RCTs) addressing source of cells and choice of donor for allogeneic haematopoietic cell transplantation (HCT) was performed to create a network of best evidence that allows us to identify new potential indirect comparisons for the strategic development of future studies that connect to the existing evidence network.

Results

A total of 19 eligible RCTs (2589 total patients) were identified. Nine studies (1566 patients) compared clinical outcomes following the use of peripheral blood progenitor cells (PBPCs) with bone marrow (BM) from matched related donors (eight studies) or matched unrelated donors (one study). The remaining studies compared BM or PBPCs with various methods of BM stimulation or manipulation (six studies), compared different methods of surface molecule‐based selection and/or depletion of grafts (two studies) or compared the optimal number of units for paediatric cord blood transplantation (two studies). No published RCTs compared different types of donors. The geometry of the evidence network was analysed to identify opportunities for potential novel indirect comparisons and to identify opportunities to expand the network. Few indirect comparisons are currently feasible due to small sample size and heterogeneity in patient diagnoses and demographics between treatment nodes in the network.

Conclusion

More RCTs that enrol greater numbers of similar patients are needed to leverage the current evidence network concerning donor choice and source of cells used in allogeneic HCT.
Centromeric DNA characterization in the model grass Brachypodium distachyon provides insights on the evolution of the genus
Authors: Li Yinjia , Zuo Sheng , Zhang Zhiliang , Li Zhanjie , Han Jinlei , Chu Zhaoqing , Hasterok Robert , Wang Kai
Published: January 2018

Brachypodium distachyon is a well‐established model monocot plant, and its small and compact genome has been used as an accurate reference for the much larger and often polyploid genomes of cereals such as Avena sativa (oats), Hordeum vulgare (barley) and Triticum aestivum (wheat). Centromeres are indispensable functional units of chromosomes and they play a core role in genome polyploidization events during evolution. As the Brachypodium genus contains about 20 species that differ significantly in terms of their basic chromosome numbers, genome size, ploidy levels and life strategies, studying their centromeres may provide important insight into the structure and evolution of the genome in this interesting and important genus. In this study, we isolated the centromeric DNA of the B. distachyon reference line Bd21 and characterized its composition via the chromatin immunoprecipitation of the nucleosomes that contain the centromere‐specific histone CENH3. We revealed that the centromeres of Bd21 have the features of typical multicellular eukaryotic centromeres. Strikingly, these centromeres contain relatively few centromeric satellite DNAs; in particular, the centromere of chromosome 5 (Bd5) consists of only ~40 kb. Moreover, the centromeric retrotransposons in B. distachyon (CRBds) are evolutionarily young. These transposable elements are located both within and adjacent to the CENH3 binding domains, and have similar compositions. Moreover, based on the presence of CRBds in the centromeres, the species in this study can be grouped into two distinct lineages. This may provide new evidence regarding the phylogenetic relationships within the Brachypodium genus.
Grapevine field experiments reveal the contribution of genotype, the influence of environment and the effect of their interaction (G×E) on the berry transcriptome
Authors: Dal Santo Silvia , Zenoni Sara , Sandri Marco , De Lorenzis Gabriella , Magris Gabriele , De Paoli Emanuele , Di Gaspero Gabriele , Del Fabbro Cristian , Morgante Michele , Brancadoro Lucio , Grossi Daniele , Fasoli Marianna , Zuccolotto Paola , Tornielli Giovanni Battista , Pezzotti Mario
Published: January 2018

Changes in the performance of genotypes in different environments are defined as genotype × environment (G×E) interactions. In grapevine (Vitis vinifera), complex interactions between different genotypes and climate, soil and farming practices yield unique berry qualities. However, the molecular basis of this phenomenon remains unclear. To dissect the basis of grapevine G×E interactions we characterized berry transcriptome plasticity, the genome methylation landscape and within‐genotype allelic diversity in two genotypes cultivated in three different environments over two vintages. We identified, through a novel data‐mining pipeline, genes with expression profiles that were: unaffected by genotype or environment, genotype‐dependent but unaffected by the environment, environmentally‐dependent regardless of genotype, and G×E‐related. The G×E‐related genes showed different degrees of within‐cultivar allelic diversity in the two genotypes and were enriched for stress responses, signal transduction and secondary metabolism categories. Our study unraveled the mutual relationships between genotypic and environmental variables during G×E interaction in a woody perennial species, providing a reference model to explore how cultivated fruit crops respond to diverse environments. Also, the pivotal role of vineyard location in determining the performance of different varieties, by enhancing berry quality traits, was unraveled.
An integrated multi‐layered analysis of the metabolic networks of different tissues uncovers key genetic components of primary metabolism in maize
Authors: Wen Weiwei , Jin Min , Li Kun , Liu Haijun , Xiao Yingjie , Zhao Mingchao , Alseekh Saleh , Li Wenqiang , de Abreu e Lima Francisco , Brotman Yariv , Willmitzer Lothar , Fernie Alisdair R. , Yan Jianbing
Published: January 2018

Primary metabolism plays a pivotal role in normal plant growth, development and reproduction. As maize is a major crop worldwide, the primary metabolites produced by maize plants are of immense importance from both calorific and nutritional perspectives. Here a genome‐wide association study (GWAS) of 61 primary metabolites using a maize association panel containing 513 inbred lines identified 153 significant loci associated with the level of these metabolites in four independent tissues. The genome‐wide expression level of 760 genes was also linked with metabolite levels within the same tissue. On average, the genetic variants at each locus or transcriptional variance of each gene identified here were estimated to have a minor effect (4.4–7.8%) on primary metabolic variation. Thirty‐six loci or genes were prioritized as being worthy of future investigation, either with regard to functional characterization or for their utility for genetic improvement. This target list includes the well‐known opaque 2 (O2) and lkr/sdh genes as well as many less well‐characterized genes. During our investigation of these 36 loci, we analyzed the genetic components and variations underlying the trehalose, aspartate and aromatic amino acid pathways, thereby functionally characterizing four genes involved in primary metabolism in maize.
Chemical management of weeds in corn hybrids
Authors: Galon Leandro , De David Felipe A. , Forte César T. , Júnior Francisco W.R. , Radunz André L. , Kujawinski Renato , Radunz Lauri L. , Castoldi Camile T. , Perin Gismael F. , Mossi Altemir J.
Published: January 2018

Corn stands out among the cultivars because of its high importance in food, animal feed and raw materials for energy production. The quantity and quality of the harvested grain can be reduced, mainly due to inadequate weed management. Nowadays, weed control is accomplished with the use of herbicides as pre‐emergence and postemergence, applied alone or in a tank mix. This study aimed to evaluate the efficiency of the control of weeds and phytotoxicity of the herbicides that were applied in tank mix or isolated in the corn hybrids, Formula TL® and SYN 7B28. Two experiments were conducted: in the 2012/2013 season (Formula TL®) and 2013/2014 season (SYN 7B28). There was a low initial phytotoxicity of all the tested herbicides in the initial evaluation; however, from 14 days after treatment, it was minimal. The weed control of Ipomoea indivisa, Urochloa plantaginea and Euphorbia heterophylla in both experiments was better, in general, when using the tank mixtures of atrazine + simazine + tembotrione and atrazine + simazine + mesotrione, respectively. The application of atrazine + simazine + tembotrione in the SYN 7B28 hybrids provided, with the exception of the thousand‐grain weight, the best expression of grain yield components, combining a low phytotoxicity and best control of the weeds. The Formula TL® hybrid presented the highest mass of a thousand grains and yield with the application of nicosulfuron + tembotrione. The yield average difference of the herbicide treatments and the unweeded control showed an increase of 27.66 and 34.59% in the grain yield of the corn hybrids, Formula TL® and SYN 7B28, respectively.
Birational invariance in logarithmic Gromov–Witten theory
Authors: Abramovich Dan , Wise Jonathan
Published: January 2018

Gromov–Witten invariants have been constructed to be deformation invariant, but their behavior under other transformations is subtle. We show that logarithmic Gromov–Witten invariants are also invariant under appropriately defined logarithmic modifications.
Hypothalamic and liver transcriptome from two crucial life‐history stages in a migratory songbird
Authors: Sharma Aakansha , Singh Devraj , Das Subhajit , Kumar Vinod
Published: January 2018

New Findings

What is the central question of this study?

What are the molecular underpinnings of the seasonal adaptation in a latitudinal migratory songbird?

What is the main finding and its importance?

We found changes in mRNA levels after a photoperiod‐induced alteration of seasonal state in a captive long‐distance latitudinal avian migrant. The hypothalamus and liver transcriptomes revealed genes involved in the regulatory and functional pathways between non‐migratory and migratory states. Our results provide insights into mechanisms underlying homeostasis during seasonal changes that are conserved across most species, including humans.

Very little is understood about genetic mechanisms underlying the onset of spring migration in latitudinal avian migrants. To gain insight into the genetic architecture of the hypothalamus and liver tissues of a long‐distance migrant, we examined and compared the transcriptome profile of captive night‐migratory black‐headed buntings (Emberiza melanocephala) between photoperiod‐induced winter non‐migratory (WnM) and spring migratory (SM) life‐history states under short and long days, respectively. High‐throughput 454 pyrosequenced transcripts were mapped initially with reference to the genome of two phylogenetically close species, Taeniopygia guttata and Ficedula albicollis. The F. albicollis genome gave higher annotation results and was used for further analysis. A total of 216 (78 in hypothalamus; 138 in liver) genes were found to be expressed differentially between the WnM and SM life‐history states. These genes were enriched for physiological pathways that might be involved in the regulation of seasonal migrations in birds. For example, genes for the ATP binding pathway in the hypothalamus were expressed at a significantly higher level in SM than in the WnM life‐history state. Likewise, upregulated genes associated with the myelin sheath and focal adhesion were enriched in the hypothalamus, and those with cell‐to‐cell junction, intracellular protein transport, calcium ion transport and small GTPase‐mediated signal transduction were enriched in the liver. Many of these genes are a part of physiological pathways potentially involved in the regulation of seasonal migration in birds. These results show molecular changes at the regulatory and metabolic levels associated with seasonal transitions in a long‐distance migrant and provide the basis for future studies aimed at unravelling the genetic control of migration in birds.
Endothelial immune activation programmes cell‐fate decisions and angiogenesis by inducing angiogenesis regulator DLL4 through TLR4‐ERK‐FOXC2 signalling
Authors: Xia Sheng , Menden Heather L. , Korfhagen Thomas R. , Kume Tsutomu , Sampath Venkatesh
Published: January 2018

Key points

The mechanisms by which bacteria alter endothelial cell phenotypes and programme inflammatory angiogenesis remain unclear.

In lung endothelial cells, we demonstrate that toll‐like receptor 4 (TLR4) signalling induces activation of forkhead box protein C2 (FOXC2), a transcriptional factor implicated in lymphangiogenesis and endothelial specification, in an extracellular signal‐regulated kinase (ERK)‐dependent manner.

TLR4‐ERK‐FOXC2 signalling regulates expression of the Notch ligand DLL4 and signals inflammatory angiogenesis in vivo and in vitro.

Our work reveals a novel link between endothelial immune signalling (TLR pathway) and a vascular transcription factor, FOXC2, that regulates embryonic vascular development.

This mechanism is likely to be relevant to pathological angiogenesis complicating inflammatory diseases in humans.

Endothelial cells (ECs) mediate a specific and robust immune response to bacteria in sepsis through the activation of toll‐like receptor (TLR) signalling. The mechanisms by which bacterial ligands released during sepsis programme EC specification and altered angiogenesis remain unclear. We postulated that the forkhead box protein C2 (FOXC2) transcriptional factor directs EC cell‐fate decisions and angiogenesis during TLR signalling. In human lung ECs, lipopolysaccharide (LPS) induced ERK phosphorylation, FOXC2, and delta‐like 4 (DLL4, the master regulator of sprouting angiogenesis expression) in a TLR4‐dependent manner. LPS‐mediated ERK phosphorylation resulted in FOXC2‐ERK protein ligation, ERK‐dependent FOXC2 serine and threonine phosphorylation, and subsequent activation of DLL4 gene expression. Chemical inhibition of ERK or ERK‐2 dominant negative transfection disrupted LPS‐mediated FOXC2 phosphorylation and transcriptional activation of FOXC2. FOXC2‐siRNA or ERK‐inhibition attenuated LPS‐induced DLL4 expression and angiogenic sprouting in vitro. In vivo, intraperitoneal LPS induced ERK and FOXC2 phosphorylation, FOXC2 binding to DLL4 promoter, and FOXC2/DLL4 expression in the lung. ERK‐inhibition suppressed LPS‐induced FOXC2 phosphorylation, FOXC2‐DLL4 promoter binding, and induction of FOXC2 and DLL4 in mouse lung ECs. LPS induced aberrant retinal angiogenesis and DLL4 expression in neonatal mice, which was attenuated with ERK inhibition. FOXC2+/− mice treated with LPS showed a mitigated increase in FOXC2 and DLL4 compared to FOXC2+/+ mice. These data reveal a new mechanism (TLR4‐ERK‐FOXC2‐DLL4) by which sepsis‐induced EC TLR signalling programmes EC specification and altered angiogenesis.
Imbalance of synaptic actin dynamics as a key to fragile X syndrome?
Authors: Michaelsen‐Preusse Kristin , Feuge Jonas , Korte Martin
Published: January 2018

Our experiences and memories define who we are, and evidence has accumulated that memory formation is dependent on functional and structural adaptations of synaptic structures in our brain. Especially dendritic spines, the postsynaptic compartments of synapses show a strong structure‐to‐function relationship and a high degree of structural plasticity. Although the molecular mechanisms are not completely understood, it is known that these modifications are highly dependent on the actin cytoskeleton, the major cytoskeletal component of the spine. Given the crucial involvement of actin in these mechanisms, dysregulations of spine actin dynamics (reflected by alterations in dendritic spine morphology) can be found in a variety of neurological disorders ranging from schizophrenia to several forms of autism spectrum disorders such as fragile X syndrome (FXS). FXS is caused by a single mutation leading to an inactivation of the X‐linked fragile X mental retardation 1 gene and loss of its gene product, the RNA‐binding protein fragile X mental retardation protein 1 (FMRP), which normally can be found both pre‐ and postsynaptically. FMRP is involved in mRNA transport as well as regulation of local translation at the synapse, and although hundreds of FMRP‐target mRNAs could be identified only a very few interactions between FMRP and actin‐regulating proteins have been reported and validated. In this review we give an overview of recent work by our lab and others providing evidence that dysregulated actin dynamics might indeed be at the very base of a deeper understanding of neurological disorders ranging from cognitive impairment to the autism spectrum.

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Bayesian Network Learning for Data-Driven Design
Authors: Hu Zhen , Mahadevan Sankaran
Published: January 2018

Bayesian networks (BNs) are being studied in recent years for system diagnosis, reliability analysis, and design of complex engineered systems. In several practical applications, BNs need to be learned from available data before being used for design or other purposes. Current BN learning algorithms are mainly developed for networks with only discrete variables. Engineering design problems often consist of both discrete and continuous variables. This paper develops a framework to handle continuous variables in BN learning by integrating learning algorithms of discrete BNs with Gaussian mixture models (GMMs). We first make the topology learning more robust by optimizing the number of Gaussian components in the univariate GMMs currently available in the literature. Based on the BN topology learning, a new multivariate Gaussian mixture (MGM) strategy is developed to improve the accuracy of conditional probability learning in the BN. A method is proposed to address this difficulty of MGM modeling with data of mixed discrete and continuous variables by mapping the data for discrete variables into data for a standard normal variable. The proposed framework is capable of learning BNs without discretizing the continuous variables or making assumptions about their conditional probability densities (CPDs). The applications of the learned BN to uncertainty quantification and model calibration are also investigated. The results of a mathematical example and an engineering application example demonstrate the effectiveness of the proposed framework.
Interactive Multiple Model Filter for Tracking a Pursuer With Proportional Navigation Guidance Law
Authors: Du Runle , Zou Xinguang , Zhou Di , Liu Jiaqi
Published: January 2018

This paper addresses a pursuer tracking problem where the pursuer's acceleration is given by a proportional navigation (PN) guidance law with a time-varying navigation ratio which varies with the relative range between the pursuer and its target. Based on a motion model that exactly describes the relative motion and the PN guidance law, a novel filter for tracking such a pursuer is designed using interactive multiple model (IMM) algorithm and unscented Kalman filtering (UKF) technique. This filter is able to accurately estimate the relative range, relative velocity, and the acceleration of pursuer even if the pursuer adopts a PN guidance law with time-varying navigation ratio. The proposed tracking method is evaluated in extensive Monte Carlo simulations. It is shown that accurate estimation results have been obtained, and the model probabilities in the IMM UKF filter are consistent with real situations.
Analysis of Soft-Elastohydrodynamic Lubrication Line Contacts on Finite Thickness
Authors: Chen Qie-Da , Li Wang-Long
Published: January 2018

Soft elastohydrodynamic lubrication (soft-EHL) is an important mechanism in biotribological systems. The soft-EHL has some distinct differences from the traditional hard-EHL, and a systematic analysis factoring in key features of the “softness” appears to be lacking. In this paper, a complete soft-EHL line-contact model is developed. In the model, the half-space approximation is replaced by the finite thickness analysis; the geometrical and material nonlinearity due to finite deformation is factored in; the surface velocities altered by the curvature effect are considered, and the load balance equation is formulated based on the deformed configuration. Solutions are obtained using a finite element method (FEM). The film thickness, pressure distributions, and material deformation are analyzed and discussed under various entraining velocities, elastic modulus, and material thickness of the soft layer. Comparisons are made between soft-EHL and hard-EHL modeling assumptions. The analyses show that the classical EHL modeling is not suitable for soft materials with high loads. The results show that the finite deformation (Green strain) should be considered in soft-EHL analysis. In the contact region, the hard EHL solver overestimates the pressure distribution and underestimates the film thickness and deformation.
New species and reports of scutacarid mites from Andalusia, Spain, (Heterostigmatina, Scutacaridae)
Authors: Baumann Julia , Ferragut Francisco
Published: January 2018

Knowledge about the fauna of scutacarid mites (Heterostigmatina, Pygmephoroidea, Scutacaridae) on the Iberian Peninsula is very scarce. In order to increase information on Iberian scutacarids, collections were performed in the south of Andalusia, resulting in one new species Scutacarus tarifae sp. nov. and four new records for the Iberian Peninsula: Diversipes exhamulatus (Michael, 1886), Scutacarus carinthiacus Ebermann, 1979, S. echidna (Berlese, 1905) and S. eucomus (Berlese, 1908). The first descriptions of male and larva of S. eucomus are provided, and the unusual shape of the pharyngeal pumps of S. carinthiacus is discussed.
Growth of high-quality Bi2Se3 topological insulators using (Bi1-xInx)2Se3 buffer layers
Authors: Wang Yong , Ginley Theresa P. , Law Stephanie
Published: January 2018

In this article, the authors first report on the optimum growth parameters for (Bi1-xInx)2Se3 alloys of arbitrary composition using molecular beam epitaxy. It is found that smooth, single-phase films can only be obtained by using a sequential growth and annealing method to seed the film, after which normal codeposition growth can be used. The topological insulator Bi2Se3 is then grown on top of various (Bi1-xInx)2Se3 buffers and the electrical properties measured. For Bi2Se3 films grown on high-quality buffer layers, the mobility is greatly enhanced and the carrier density reduced compared to growth directly on sapphire substrates, indicating a significant improvement in film quality. The use of an almost lattice-matched trivially insulating buffer layer is therefore crucial to the growth of high-quality topological insulators on arbitrary substrates.
Off-axis targets maximize bearing Fisher Information in broadband active sonar
Authors: Kloepper Laura N. , Buck John R. , Liu Yang , Nachtigall Paul E.
Published: January 2018

Broadband active sonar systems estimate range from time delay and velocity from Doppler shift. Relatively little attention has been paid to how the received echo spectrum encodes information about the bearing of an object. This letter derives the bearing Fisher Information encoded in the frequency dependent transmitter beampattern. This leads to a counter-intuitive result: directing the sonar beam so that a target of interest is slightly off-axis maximizes the bearing information about the target. Beam aim data from a dolphin biosonar experiment agree closely with the angle predicted to maximize bearing information.
EGFR-induced cytoskeletal changes drive complex cell behaviors: The tip of the iceberg
Authors: Chiasson-MacKenzie Christine , McClatchey Andrea I.
Published: January 2018

Epidermal growth factor signaling is interconnected with cytoskeletal dynamics in cancer cells (Roth
et al
. and Pike
et al
., in 30 January 2018 issue).