bluuebunny/crossref_metadata_2025 huggingface dataset:
PM2.5 exposure induces systemic inflammation and oxidative stress in an intracranial atherosclerosis rat model
Authors: Guan Longfei , Geng Xiaokun , Stone Christopher , Cosky Eric E. P. , Ji Yu , Du Huishan , Zhang Kezhong , Sun Qinghua , Ding Yuchuan
Published: January 2019

Objectives

Exposure to airborne particle (PM2.5) is a risk factor for intracranial atherosclerosis (ICA). Because of the established role of systemic inflammation and oxidative stress by PM2.5, we determined whether these processes account for PM2.5‐mediated ICA, and also whether omega‐3 fatty acid (O3FA) dietary supplementation could attenuate them.

Methods

Adult Sprague‐Dawley rats were exposed to filtered air (FA) or PM2.5 and fed either a normal chow diet (NCD) or a high‐cholesterol diet (HCD), administered with or without O3FA (5 mg/kg/day by gavage) for 12 weeks. The lumen and thickness of the middle cerebral artery (MCA) were assessed. Serum tumor necrosis factor alpha (TNF‐α), interleukin 6 (IL‐6), interleukin‐1β (IL‐1β), and interferon gamma (IFN‐γ) were detected by ELISA. Reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD) activity, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activity, mRNA levels of Nrf2, HO‐1, NQO‐1, and protein level of NOX subunit gp91 were quantified to determine the oxidative profile of brain vessels.

Results

PM2.5 increased (P < .05) ICA, especially in the HCD group; elevated serum TNF‐α, IL‐6, IL‐1β, and IFN‐γ; increased cerebrovascular ROS, MDA, NOX activity, and gp91 protein levels; and decreased cerebrovascular SOD activity. Nrf2, HO‐1, and NQO‐1 mRNA levels were upregulated (P < .05) by PM2.5 exposure, especially in the HCD group. O3FA attenuated (P < .05) PM2.5‐induced systemic inflammation, vascular oxidative injury, and ICA.

Conclusions

PM2.5 exposure induced systemic inflammation, cerebrovascular oxidative injury, and ICA in rats with HCD. O3FA prevented ICA development, and may therefore exert a protective effect against the atherogenic potential of PM2.5.
Optimization of turbine design in wind farms with multiple hub heights, using exact analytic gradients and structural constraints
Authors: Stanley Andrew P.J. , Ning Andrew , Dykes Katherine
Published: January 2019

Wind farms are generally designed with turbines of all the same hub height. If wind farms were designed with turbines of different hub heights, wake interference between turbines could be reduced, lowering the cost of energy (COE). This paper demonstrates a method to optimize onshore wind farms with two different hub heights using exact, analytic gradients. Gradient‐based optimization with exact gradients scales well with large problems and is preferable in this application over gradient‐free methods. Our model consisted of the following: a version of the FLOw Redirection and Induction in Steady‐State wake model that accommodated three‐dimensional wakes and calculated annual energy production, a wind farm cost model, and a tower structural model, which provided constraints during optimization. Structural constraints were important to keep tower heights realistic and account for additional mass required from taller towers and higher wind speeds. We optimized several wind farms with tower height, diameter, and shell thickness as coupled design variables. Our results indicate that wind farms with small rotors, low wind shear, and closely spaced turbines can benefit from having two different hub heights. A nine‐by‐nine grid wind farm with 70‐meter rotor diameters and a wind shear exponent of 0.08 realized a 4.9% reduction in COE by using two different tower sizes. If the turbine spacing was reduced to 3 diameters, the reduction in COE decreased further to 11.2%. Allowing for more than two different turbine heights is only slightly more beneficial than two heights and is likely not worth the added complexity.
Statistical nonparametric mapping: Multivariate permutation tests for location, correlation, and regression problems in neuroimaging
Authors: Helwig Nathaniel E.
Published: January 2019

Nonparametric statistical inference via permutation testing is on the rise in neuroimaging research. This rise in popularity is likely in response to recent studies that have demonstrated limitations of parametric inference in certain situations. Nonparametric tests have the appeal of requiring fewer assumptions than their parametric counterparts, and are often touted as being more flexible and more useful for small samples. Furthermore, recent studies have demonstrated the robustness of nonparametric methods in situations when parametric inference fails. As a result, many nonstatistical neuroimaging researchers are likely to believe that nonparametric permutation tests are always a “safe choice” because the results do not depend on distributional assumptions and/or large sample approximations. Alas, this commonly held belief is not entirely accurate, given that nonparametric tests still do rely on assumptions and/or approximations for valid statistical inference. When these assumptions are met, nonparametric permutation tests have the potential to produce valid inferential results for the intended hypotheses. However, as I demonstrate, when these assumptions are violated, nonparametric permutation tests can produce invalid and/or misleading results, which have important implications for the use of such methods in neuroimaging research. All hope is not lost though, as recent theoretical developments in nonparametric statistics can improve current implementations of permutation tests in neuroimaging research.

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Nonparametric Methods

Statistical and Graphical Methods of Data Analysis > Bootstrap and Resampling

Data: Types and Structure > Image and Spatial Data
α‐Fe2O3 Polyhedral Nanoparticles Enclosed by Different Crystal Facets: Tunable Synthesis, Formation Mechanism Analysis, and Facets‐dependent n‐Butanol Sensing Properties
Authors: Xu Yanyan , Tian Xin , Sun Dandan , Sun Yaqiu , Gao Dongzhao
Published: January 2019

Three kinds of polyhedral α‐Fe2O3 nanoparticles enclosed by different facets including oblique parallel hexahedrons (op‐hexahedral NPs), cracked oblique parallel hexahedrons (cop‐hexahedral NPs), and octadecahedral nanoparticles (octadecahedral NPs), were successfully prepared by simply changing only one reaction parameter in the hydrothermal process. The structural and morphological of the products were systematically studied using various characterizations including X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), revealing that the three kinds of α‐Fe2O3 nanoparticles were enclosed by {104}, {110}/{104}, and {102}/{012}/{104} crystal planes, respectively. The exposed facets and shape of the nanocrystals were found to be affected by the adding amount of ethylene glycol in the solvent. The gas‐sensing properties and mechanism of the α‐Fe2O3 samples were studied and analyzed, which indicated that the sensitivity of the three samples followed the order of octadecahedral NPs > cop‐hexahedral NPs > op‐hexahedral NPs due to the combined effects of specific surface area and oxygen defects in the nanocrystals.
From Luminescent Complexes to Framework Formation from Ln‐trichlorides and Pyrazine
Authors: Matthes Philipp R. , Müller‐Buschbaum Klaus
Published: January 2019

The three‐dimensional framework 3∞[LaCl3(pyz)] and the dimeric complexes [Ln2Cl6(pyz)(py)6]·2pyz (Ln = Sm, Er) were obtained from solvothermal reaction of the respective chlorides LnCl3 with pyrazine (pyz) in pyridine (py) at 200 °C. In the compounds, pyrazine ligands interlink Ln‐cations: in the complexes to a dimer, in the framework structure to 2D sheets, which are further connected via chloride bridges. This results in an uninodal 6‐c net with the point symbol (48.67) and a variant of the sxa topology. The dimeric complexes exhibit 4f‐based emission in the visible for samarium and in the NIR for erbium, both sensitized by the pyrazine ligands, as mechanistic insights show.
Integrated Collection Assessment and Planning (ICAP) workshop: Helping zoos move toward the One Plan Approach
Authors: Traylor‐Holzer Kathy , Leus Kristin , Bauman Karen
Published: January 2019

Most threatened species do not yet have an integrated conservation plan to guide zoos and aquariums in species selection and conservation action. To address this issue, the Conservation Planning Specialist Group (CPSG), in collaboration with regional zoo and aquarium associations, has developed a new process—an Integrated Collection Assessment and Planning (ICAP) workshop. This brings in situ and ex situ communities together to apply the decision process of the IUCN SSC Guidelines on the Use of Ex Situ Management for Species Conservation to the task of regional or global collection planning. The first ICAP workshop was held in 2016 for 43 canids and hyaenids in collaboration with the relevant regional zoo and aquarium associations and IUCN Specialist Groups. The ICAP process provides a comprehensive assessment that will enhance species conservation by providing guidance to zoos and aquariums on conservation priorities for collection planning, conservation education messaging, in situ field support, and integration of in situ and ex situ efforts, as well as by promoting collaboration among regional zoo and aquarium associations, field‐based conservationists, and IUCN SSC Specialist Groups.
Maritime/Marine Spatial Planning at the Interface of Research and Practice
Authors: Ehler Charles , Zaucha Jacek , Gee Kira
Published: January 2019

This chapter introduces marine/maritime spatial planning (MSP) from the perspective of research and practice. After providing some basic definitions and terminology, it shows how MSP has developed since its inception, ending with a description of its current status of adoption around the world. It also sets out how MSP has been received in various academic disciplines and traces some of the key discussions that have emerged. The chapter closes by providing a brief overview of the subsequent chapters.
Towards a Ladder of Marine/Maritime Spatial Planning Participation
Authors: Morf Andrea , Kull Michael , Piwowarczyk Joanna , Gee Kira
Published: January 2019

Presently, institutional systems and practices in marine/maritime spatial planning (MSP) are evolving rapidly. At the same time, cross-border learning and exchange are still at an early stage. This chapter is based on the need to assess and compare participation processes across cases and countries and foster learning to develop public participation in MSP. Based on theoretical reflections, but anchored in results derived from the BaltSpace and the Baltic SCOPE projects, we present an analytical framework to characterise participation in MSP, including a participation ladder emphasising power sharing, roles, functions and learning. It is inspired by the land-based planning discourse, rural development literature, natural resource and conflict management and the latest publications with an MSP perspective including one in this book.
Stakeholder Processes in Marine Spatial Planning: Ambitions and Realities from the European Atlantic Experience
Authors: Twomey Sarah , O’Mahony Cathal
Published: January 2019

Marine Spatial Planning (MSP) requires the participation of various stakeholders representing the multiple sectors operating in any given planning area. At a theoretical level, early and effective stakeholder participation is a fundamental aspect of MSP; it is also a legal requirement under a host of international and European instruments. This chapter explores the real-life challenges associated with delivering multi-sector participatory MSP processes. Insights and practical recommendations are drawn from five case studies from Europe’s Atlantic sea basin including a research-based civil-society-led transboundary MSP pilot project, and four statutory initiatives from EU Member States on the island of Ireland and the Iberian coast. Various degrees of disconnect are identified between the conceptual underpinnings of MSP theory and the reality of recent stakeholder processes.
Managing Risk Through Marine Spatial Planning
Authors: Cormier Roland , Kannen Andreas
Published: January 2019

Governance and management are inherently risk management processes. In a management context, risk is related to the uncertainties of achieving set objectives. Risk assessment is used to identify and analyse risks in terms of likelihood and consequences. This chapter relates risk to the process of developing a maritime spatial plan. Risk may arise from not identifying and understanding the risks perceived by stakeholders, from not having specific goals and objectives or from unclear structures and decision-making rules. For the plan itself, risks are related to not having adequate spatial allocation for activities to achieve set objectives. Risk may also be related to not having the authority needed to lead the planning process and, subsequently, implement the spatial allocation identified in the plan.
The Role of the Law of the Sea in Marine Spatial Planning
Authors: Pyć Dorota
Published: January 2019

The United Nations Convention on the Law of the Sea (UNCLOS) is a globally recognized legal regime. UNCLOS has been widely regarded as a “constitution for the oceans” and enshrines the notion that “the problems of ocean space are closely interrelated and need to be considered as a whole”. In compliance with the concept of effective enforcement of international norms, standards and procedures, State Parties to UNCLOS have an obligation to preserve the marine environment. The purpose of this chapter is to consider the role of the law of the sea in marine spatial planning (MSP), bearing in mind that UNCLOS has also provided the framework for the further development of, inter alia, global ocean governance.
Adding People to the Sea: Conceptualizing Social Sustainability in Maritime Spatial Planning
Authors: Saunders Fred P. , Gilek Michael , Tafon Ralph
Published: January 2019

While there is growing critique emerging to address social sustainability in marine/maritime spatial planning (MSP), overwhelmingly attention has been on governance, economic and environmental aspects. This chapter redresses this by proposing a conceptual framework to elucidate key features of social sustainability in MSP. The ambition is to both note the existing critique of MSP and go beyond it by more clearly and comprehensively articulating how social sustainability could be conceived in MSP, as well as how this framework could be applied to analyse MSP practice. Key features of social sustainability elaborated are: deepening democratic decision-making, inclusion of socio-cultural values and knowledge, equitable distribution and social cohesion. Finally, the chapter concludes by nominating strategies to give greater visibility to social sustainability as a key MSP concern.
Understanding and Going Beyond the Regional Policy Paradox: Conceptual Contributions to Studying Socio-Spatial Polarisation in Europe
Authors: Raagmaa Garri , Nagy Erika , Görmar Franziska , Lang Thilo
Published: January 2019

The goal of this penultimate chapter is to shed light on the conceptual value of the book. Growing social polarisation and economic inequalities unfolding in new forms across various places have brought about academic and policy debates on the meanings of ‘development’, the ways its dimensions (economic, social, cultural, political) are interrelated, and on how macro-structural changes are entangled with local and regional processes as well as institutional and social contexts. This chapter adds to this discussion by providing a better understanding of five interrelated topics: (1) the regional policy paradox in the European Union, (2) historical legacies leading to administrative centralisation trends in Eastern Europe, (3) globalisation and regional industrial restructuring causing further polarisation, (4) the mechanisms that bring about inequalities, and (5) the production of inequalities through social practices and discourses. Based on these key topics, the chapter argues for more agency-centred research in peripheral contexts, which focuses on how actors, organisations and institutions shape the development of currently peripheralised places.
“New” Questions of Peripherality in Europe or How Neoliberal Austerity Contradicts Socio-Spatial Cohesion
Authors: Hadjimichalis Costis
Published: January 2019

In the context of the deep multidimensional crisis of the European Union that threatens its existence, this chapter discusses processes of uneven geographical development that produce and reproduce peripherality in Europe and beyond. In particular, it discusses two parameters. First, how imaginations of peripherality shape development theories and policies and, second, how such imaginations and development policies may contribute to deepening unevenness and peripherality. The chapter concludes by raising some questions concerning the current socio-spatial situation in the European Union.
Urban Growth Pole Policy and Regional Development: Old Wine in New Bottles?
Authors: Benedek József , Varvari Ştefana , Litan Cristian Marius
Published: January 2019

As part of a broader Europeanisation process, the general guidelines and principles of European spatial planning documents have been uncritically adopted in the Romanian spatial development system during the last two decades. One of them is related to the concept of polycentric development, translated in the Romanian planning system through the selection and development of growth poles. The main aim of this chapter is to evaluate the process and outcome of establishing urban growth poles as key elements of the new regional policy in Romania. In particular, the chapter addresses the question whether the high prioritisation of urban growth poles has reduced the level of regional disparities in Romania, or, in contrast, whether it has contributed to an increase of regional disparities. The chapter highlights the failure of regional policy in achieving its essential objective: the reduction of internal regional disparities in the long term. Even though the capital city, Bucharest, was excluded from the analysis and thus the level of disparities is underestimated, the authors found that disparities among cities and counties reduced during the programming period 2007–2013 and started to increase again as soon as the programme ended.
Vertex algebras at the corner
Authors: Gaiotto Davide , Rapčák Miroslav
Published: January 2019

Abstract

We introduce a class of Vertex Operator Algebras which arise at junctions of supersymmetric interfaces in

$$ \mathcal{N} $$

N

= 4 Super Yang Mills gauge theory. These vertex algebras satisfy non-trivial duality relations inherited from S-duality of the four-dimensional gauge theory. The gauge theory construction equips the vertex algebras with collections of modules labelled by supersymmetric interface line defects. We discuss in detail the simplest class of algebras Y

L,M,N
, which generalizes W

N
algebras. We uncover tantalizing relations between Y

L,M,N
, the topological vertex and the W
1+∞ algebra.
All two-loop MHV remainder functions in multi-Regge kinematics
Authors: Del Duca Vittorio , Duhr Claude , Dulat Falko , Penante Brenda
Published: January 2019

Abstract

We introduce a method to extract the symbol of the coefficient of (2πi)2 of MHV remainder functions in planar

$$ \mathcal{N} $$

N

= 4 Super Yang-Mills in multi-Regge kinematics region directly from the symbol in full kinematics. At two loops this symbol can be uplifted to the full function in a unique way, without any beyond-the-symbol ambiguities. We can therefore determine all two-loop MHV amplitudes at function level in all kinematic regions with different energy signs in multi-Regge kinematics. We analyse our results and we observe that they are consistent with the hypothesis of a contribution from the exchange of a three-Reggeon composite state starting from two loops and eight points in certain kinematic regions.
Quantum information processing and composite quantum fields
Authors: Ramgoolam Sanjaye , Sedlák Michal
Published: January 2019

Abstract

Some beautiful identities involving hook contents of Young diagrams have been found in the field of quantum information processing, along with a combinatorial proof. We here give a representation theoretic proof of these identities and a number of generalizations. Our proof is based on trace identities for elements belonging to a class of permutation centralizer algebras. These algebras have been found to underlie the combinatorics of composite gauge invariant operators in quantum field theory, with applications in the AdS/CFT correspondence. Based on these algebras, we discuss some analogies between quantum information processing tasks and the combinatorics of composite quantum fields and argue that this can be fruitful interface between quantum information and quantum field theory, with implications for AdS/CFT.
Chiral entanglement in massive quantum field theories in 1+1 dimensions
Authors: Lencsés M. , Viti J. , Takács G.
Published: January 2019

Abstract

We determine both analytically and numerically the entanglement between chiral degrees of freedom in the ground state of massive perturbations of 1+1 dimensional conformal field theories quantised on a cylinder. Analytic predictions are obtained from a variational Ansatz for the ground state in terms of smeared conformal boundary states recently proposed by J. Cardy, which is validated by numerical results from the Truncated Conformal Space Approach. We also extend the scope of the Ansatz by resolving ground state degeneracies exploiting the operator product expansion. The chiral entanglement entropy is computed both analytically and numerically as a function of the volume. The excellent agreement between the analytic and numerical results provides further validation for Cardy’s Ansatz. The chiral entanglement entropy contains a universal O(1) term γ for which an exact analytic result is obtained, and which can distinguish energetically degenerate ground states of gapped systems in 1+1 dimensions.
Distribution of soil nitrogen and nitrogenase activity in the forefield of a High Arctic receding glacier
Authors: Turpin-Jelfs Thomas , Michaelides Katerina , Blacker Joshua J. , Benning Liane G. , Williams James M. , Anesio Alexandre M.
Published: January 2019

Glaciers retreating in response to climate warming are progressively exposing primary mineral substrates to surface conditions. As primary production is constrained by nitrogen (N) availability in these emerging ecosystems, improving our understanding of how N accumulates with soil formation is of critical concern. In this study, we quantified how the distribution and speciation of N, as well as rates of free-living biological N fixation (BNF), change along a 2000-year chronosequence of soil development in a High Arctic glacier forefield. Our results show the soil N pool increases with time since exposure and that the rate at which it accumulates is influenced by soil texture. Further, all N increases were organically bound in soils which had been ice-free for 0–50 years. This is indicative of N limitation and should promote BNF. Using the acetylene reduction assay technique, we demonstrated that microbially mediated inputs of N only occurred in soils which had been ice-free for 0 and 3 years, and that potential rates of BNF declined with increased N availability. Thus, BNF only supports N accumulation in young soils. When considering that glacier forefields are projected to become more expansive, this study has implications for understanding how ice-free ecosystems will become productive over time.
EXPERTISE AND AUTHORITY
Authors: Stewart Coran
Published: January 2019

Experts use their superior skills and understanding to mediate between evidence in some domain and non-experts. But how should we understand the proper relationship between experts and non-experts? In this paper, I present two ways of conceiving experts’ mediating role from the perspective of non-experts: the Authority View and the Advisor View. Jennifer Lackey (2018) has criticized the Authority View and defended the Advisor View. I defend an account of epistemic authority that avoids her criticisms while arguing the Advisor View lacks the advantages she claims. Ultimately, I present a hybrid approach according to which whether we should treat experts as authorities or advisors varies depending upon the presence of certain epistemic and moral concerns.
Effects of neurofeedback on the dysregulation profile in children with ADHD: SCP NF meets SDQ-DP – a retrospective analysis
Authors: Heinrich Hartmut , Gevensleben Holger , Becker Andreas , Rothenberger Aribert
Published: January 2019

Background

As children with attention-deficit/hyperactivity disorder (ADHD) usually show psychopathological signs beyond their core symptoms (e.g. elevated scores of the dysregulation profile (DP) in 30–40%), treatments with a broader approach to self-regulation skills may be supportive. Neurofeedback (NF) may reflect such an option. Aim of the present analysis was to compare the effects of slow cortical potential (SCP) NF and θ/β NF on the DP using data from a previous trial.

Methods

Thirty children with ADHD (aged 8–12 years) and a DP score in the Strengths and Difficulties Questionnaire (SDQ-DP) ⩾ 3 were included. NF treatment consisted of one block of SCP NF and one block of θ/β NF (18 units per block) allowing an intraindividual comparison. Effects of the NF protocols were also contrasted to a control group (n = 18) that completed an attention skills training (between-group analysis).

Results

Regarding the SDQ-DP, SCP NF was superior to θ/β NF and the control condition. Effects of SCP NF and θ/β NF on ADHD symptom severity were not significantly different. The SDQ-DP score did not correlate with EEG-related measures previously found to be predictors for SCP NF on ADHD symptoms.

Conclusions

SCP NF may reflect a more general approach to improve cognitive, emotional and behavioral self-regulation skills. If confirmed in a larger sample, the SDQ-DP score could be used as an indication criterion and contribute to the individualization of NF in ADHD. Overall, the differential effect provides further evidence for the specificity of NF effects.
Complete tracheal rings and hypoplastic left heart variant: a rare and fatal association
Authors: Bansal Neha , Mahadin Deemah R. , Aggarwal Sanjeev
Published: January 2019

Congenital complete tracheal rings are usually associated with pulmonary slings. We report a rare association of congenital complete tracheal rings with hypoplastic left heart variant. A term infant with diagnosis of a mildly hypoplastic mitral valve, unicuspid aortic valve, and moderately hypoplastic aortic arch with severe coarctation underwent a hybrid procedure initially. Upon failing extubation attempts, complete tracheal rings were seen on direct laryngoscopy. The combination of the lesions resulted in a poor outcome. In patients with failure of extubation post-cardiac surgery, a diagnosis of complete tracheal rings should be included in the differential and a direct laryngoscopy should be considered.
Comparative analysis of the complete chloroplast genome sequences of three Amaranthus species
Authors: Hong Su-Young , Cheon Kyeong-Sik , Yoo Ki-Oug , Lee Hyun-Oh , Mekapogu Manjulatha , Cho Kwang-Soo
Published: January 2019

The complete chloroplast (cp) genome sequences of threeAmaranthusspecies (Amaranthus hypochondriacus, A. cruentusandA. caudatus) were determined by next-generation sequencing. The cp genome sequences ofA. hypochondriacus,A. cruentusandA. caudatuswere 150,523, 150,757 and 150,523 bp in length, respectively, each containing 84 genes with identical contents and orders. Expansion or contraction of the inverted repeat region was not observed among the threeAmaranthusspecies. The coding regions were highly conserved with 99.3% homology in nucleotide and amino acid sequences. Five genes –matK,accD,ndhJ,ccsAandndhF –showed relatively high non-synonymous/synonymous values (Ka/Ks> 0.1). Sequence comparison identified two insertion/deletion (InDels) greater than 40 bp in length, and polymerase chain reaction markers that could amplify these InDel regions were applied to diverse Korean Genbank accessions, which could discriminate the threeAmaranthusspecies. Phylogenetic analyses based on 62 protein-coding genes showed that the core Caryophyllales were monophyletic and Amaranthoideae formed a sister group with the Betoideae and Chenopodioideae clade. Comparing each homologous locus among the threeAmaranthusspecies, identified eight regions with high Pi values (>0.03). Seven of these loci, except forrps19-trnH(GUG), were considered to be useful molecular markers for further phylogenetic studies.
Tillage and Cover Crop Effects on Weed Seed Persistence: Do Light Exposure and Fungal Pathogens Play a Role?
Authors: Frost Markah D. , Haramoto Erin R. , Renner Karen A. , Brainard Daniel C.
Published: January 2019

In a series of seed burial studies, we tested the hypothesis that reduced tillage and cereal rye (Secale cerealeL.) cover cropping influence seed persistence and that these effects are mediated by differences in fungal pathogens and exposure to light. Seeds of Powell amaranth (Amaranthus powelliiS. Watson) and large crabgrass [Digitaria sanguinalis(L). Scop.] were buried in mesh bags in a long-term experiment with two levels of tillage (full-width tillage [FWT] or strip tillage [ST]) and two levels of cover cropping (none or cereal rye). In Experiment 1, seeds were exhumed each spring for 3 yr and tested for viability. In Experiment 2, untreated and fungicide-treated seeds were buried, exhumed at shorter intervals, and tested for viability. In addition, a subset of seeds in FWT treatments were exhumed and stored in either light or darkness during tillage operations and evaluated for persistence at 8.5 mo after burial (MAB). In Experiment 1, the persistence ofD. sanguinalisseeds declined by 80% at 7 MAB regardless of cover crop or tillage treatment. The persistence ofA. powelliiseeds at 19 MAB declined by 95% in FWT compared with only 50% in ST. In Experiment 2, seed persistence of both species was greater in ST compared with FWT treatments, for seeds that had been exposed to light, but not for those that were maintained in darkness. Rye cover cropping resulted in a 2-fold increase in overwinter persistence of seeds ofD. sanguinalisregardless of fungicide treatment. These results demonstrate that increased persistence under ST was primarily due to reductions in light-induced fatal germination and that increased overwinter persistence ofD. sanguinalisin rye cover crop treatments could not be explained by differences in decay due to fungal pathogens controlled by the seed treatment.
Particle Size Specific Magnetic Properties Across the Norwegian‐Greenland Seas: Insights Into the Influence of Sediment Source and Texture on Bulk Magnetic Records
Authors: Hatfield Robert G. , Wheeler Benjamin H. , Reilly Brendan T. , Stoner Joseph S. , Housen Bernard A.
Published: January 2019

We make fundamental observations of the particle size variability of magnetic properties from 71 core tops that span the southern Greenland and Norwegian Seas. These data provide the first detailed regional characterization of how bulk magnetic properties vary with sediment texture, sediment source, and sediment transport. Magnetic susceptibility (MS) and hysteresis parameters were measured on the bulk sediment and the five constituent sediment particle size fractions (clay, fine silt, medium silt, coarse silt, and sand). The median MS value of the medium silt size fraction is ~3–5 times higher than that of the sand and clay size fractions and results in a strong sensitivity of bulk MS to sediment texture. Hysteresis properties of the clay size fraction are relatively homogeneous and contrast that silt and sand size fractions which show regional differences across the study area. These coarser fractions are more transport limited and using medium silt hysteresis measurements and low temperature MS behavior we establish three endmembers that effectively explain the variability observed across the region. We model the response of bulk magnetic properties to changes in sediment texture and suggest that variations in sediment source are required to explain the bulk magnetic property variability observed in cores across the southern Greenland and Norwegian Seas. These findings imply that sediment source has a greater influence on driving bulk magnetic property variability across this region than has previously been assumed.
Do We Need to Parameterize Mesoscale Convective Organization to Mitigate the MJO‐Mean State Trade‐Off?
Authors: Ahn Min‐Seop , Kim Daehyun , Park Sungsu , Ham Yoo‐Geun
Published: January 2019

Modifications in cumulus parameterizations that improve Madden‐Julian oscillation (MJO) simulation tend to degrade the mean state—known as the MJO‐mean state trade‐off. The impacts of parameterizing mesoscale convective organization on the relationship between the MJO and the mean state simulation fidelity are examined. A series of experiments are made with a general circulation model that parameterizes the mesoscale convective organization and simulates well both the MJO and the mean state. In the control simulation, a prognostic nondimensional variable (Ω) represents the degree of convective organization. In order to examine the effect of the parameterized convective organization, fixed Ω values are imposed in a series of constrained experiments. The fixed‐Ω simulations show a negative relationship between the MJO and the mean state simulation fidelity. The control simulation is deviated from the negative relationship, suggesting the parameterized mesoscale convective organization helps general circulation models to mitigate the MJO‐mean state trade‐off.
The Trend and Seasonal Change of Sediment in the East China Sea Detected by GRACE
Authors: Chang Le , Tang He , Yi Shuang , Sun Wenke
Published: January 2019

The deposition of land sediments onto the broad continental shelf of the East China Sea (ECS) is controlled by complex, dynamic hydrological mechanisms. In this study, we apply the data from Gravity Recovery and Climate Experiment (GRACE) satellite to detect the gravity signal caused by changes in sedimentation. The GRACE‐observed gravity signal is separated into the individual contributions using multisource data. After correction of each known individual signal, the sediment‐caused gravity change signal is used to invert for the sediment mass change in the ECS using a space domain inverse method. The results indicate that the total GRACE‐inverted sediment deposition rate was 0.82 ± 0.3 Gt/year from 2005 to 2015, which is in agreement with in situ sediment observations. The seasonal sediment change is also calculated and discussed. It is caused by sediment transport between the ECS and the Yellow Sea.
Permanent Thermohaline Staircases in the Tyrrhenian Sea
Authors: Durante S. , Schroeder K. , Mazzei L. , Pierini S. , Borghini M. , Sparnocchia S.
Published: January 2019

The longest historical time series (14 years, from 2003 to 2016) of temperature and salinity of thermohaline staircases with highly homogeneous and reliable data ever observed is here presented and studied. The thermohaline staircase system of the central Tyrrhenian Sea is due to double diffusion in salt finger regime, and our study reveals its conservative behavior, oscillating among slightly different shapes, passing through merging processes, with a systematic upward drift of the interfaces. Data also show enhanced salt finger processes after 2010, near the bottom, promoted by the ingression from the Western Mediterranean of a new denser water mass due to the Western Mediterranean Transition. Our results are relevant for studying the mixing in the intermediate and deep region and open the way for modeling and theoretical follow‐up studies aimed to reproduce and explain these observations.
Structural basis for species-selective targeting of Hsp90 in a pathogenic fungus
Authors: Whitesell Luke , Robbins Nicole , Huang David S. , McLellan Catherine A. , Shekhar-Guturja Tanvi , LeBlanc Emmanuelle V. , Nation Catherine S. , Hui Raymond , Hutchinson Ashley , Collins Cathy , Chatterjee Sharanya , Trilles Richard , Xie Jinglin L. , Krysan Damian J. , Lindquist Susan , Porco John A. , Tatu Utpal , Brown Lauren E. , Pizarro Juan , Cowen Leah E.
Published: January 2019

New strategies are needed to counter the escalating threat posed by drug-resistant fungi. The molecular chaperone Hsp90 affords a promising target because it supports survival, virulence and drug-resistance across diverse pathogens. Inhibitors of human Hsp90 under development as anticancer therapeutics, however, exert host toxicities that preclude their use as antifungals. Seeking a route to species-selectivity, we investigate the nucleotide-binding domain (NBD) of Hsp90 from the most common human fungal pathogen, Candida albicans. Here we report structures for this NBD alone, in complex with ADP or in complex with known Hsp90 inhibitors. Encouraged by the conformational flexibility revealed by these structures, we synthesize an inhibitor with >25-fold binding-selectivity for fungal Hsp90 NBD. Comparing co-crystals occupied by this probe vs. anticancer Hsp90 inhibitors revealed major, previously unreported conformational rearrangements. These insights and our probe’s species-selectivity in culture support the feasibility of targeting Hsp90 as a promising antifungal strategy.
Contribution of rare and common variants to intellectual disability in a sub-isolate of Northern Finland
Authors: Kurki Mitja I. , Saarentaus Elmo , Pietiläinen Olli , Gormley Padhraig , Lal Dennis , Kerminen Sini , Torniainen-Holm Minna , Hämäläinen Eija , Rahikkala Elisa , Keski-Filppula Riikka , Rauhala Merja , Korpi-Heikkilä Satu , Komulainen–Ebrahim Jonna , Helander Heli , Vieira Päivi , Männikkö Minna , Peltonen Markku , Havulinna Aki S. , Salomaa Veikko , Pirinen Matti , Suvisaari Jaana , Moilanen Jukka S. , Körkkö Jarmo , Kuismin Outi , Daly Mark J. , Palotie Aarno
Published: January 2019

The contribution of de novo variants in severe intellectual disability (ID) has been extensively studied whereas the genetics of mild ID has been less characterized. To elucidate the genetics of milder ID we studied 442 ID patients enriched for mild ID (>50%) from a population isolate of Finland. Using exome sequencing, we show that rare damaging variants in known ID genes are observed significantly more often in severe (27%) than in mild ID (13%) patients. We further observe a significant enrichment of functional variants in genes not yet associated with ID (OR: 2.1). We show that a common variant polygenic risk significantly contributes to ID. The heritability explained by polygenic risk score is the highest for educational attainment (EDU) in mild ID (2.2%) but lower for more severe ID (0.6%). Finally, we identify a Finland enriched homozygote variant in the CRADD ID associated gene.
Effects of Chemical Insecticide Imidacloprid on the Release of C6 Green Leaf Volatiles in Tea Plants (Camellia sinensis)
Authors: Zhou Qiying , Cheng Xi , Wang Shuangshuang , Liu Shengrui , Wei Chaoling
Published: January 2019

Chemical insecticides are widely used for pest control worldwide. However, the impact of insecticides on indirect plant defense is seldom reported. Here, using tea plants and the pesticide imidacloprid, effects of chemical insecticides on C6-green leaf volatiles (GLVs) anabolism and release were investigated first time. Compared with the non-treated control plants, the treatment of imidacloprid resulted in the lower release amount of key GLVs: (Z)-3-hexenal, n-hexenal, (Z)-3-hexene-1-ol and (Z)-3-Hexenyl acetate. The qPCR analysis revealed a slight higher transcript level of the CsLOX3 gene but a significantly lower transcript level of CsHPL gene. Our results suggest that imidacloprid treatment can have a negative effect on the emission of GLVs due to suppressing the critical GLVs synthesis-related gene, consequently affecting plant indirect defense.
Kinetic and thermodynamic effects of phosphorylation on p53 binding to MDM2
Authors: Yadahalli Shilpa , Neira José L. , Johnson Christopher M. , Tan Yaw Sing , Rowling Pamela J. E. , Chattopadhyay Anasuya , Verma Chandra S. , Itzhaki Laura S.
Published: January 2019

p53 is frequently mutated in human cancers. Its levels are tightly regulated by the E3 ubiquitin ligase MDM2. The complex between MDM2 and p53 is largely formed by the interaction between the N-terminal domain of MDM2 and the N-terminal transactivation (TA) domain of p53 (residues 15–29). We investigated the kinetic and thermodynamic basis of the MDM2/p53 interaction by using wild-type and mutant variants of the TA domain. We focus on the effects of phosphorylation at positions Thr18 and Ser20 including their substitution with phosphomimetics. Conformational propensities of the isolated peptides were investigated using in silico methods and experimentally by circular dichroism and 1H-NMR in aqueous solution. Both experimental and computational analyses indicate that the p53 peptides are mainly disordered in aqueous solution, with evidence of nascent helix around the Ser20-Leu25 region. Both phosphorylation and the phosphomimetics at Thr18 result in a decrease in the binding affinity by ten- to twenty-fold when compared to the wild-type. Phosphorylation and phosphomimetics at Ser20 result in a smaller decrease in the affinity. Mutation of Lys24 and Leu25 also disrupts the interaction. Our results may be useful for further development of peptide-based drugs targeting the MDM2/p53 interaction.
The viscosity-radius relationship for concentrated polymer solutions
Authors: Dunstan Dave E.
Published: January 2019

A key assumption of polymer physics is that the random chain polymers extend in flow. Recent experimental evidence has shown that polymer chains compress in Couette flow in a manner counter to expectation. Here, scaling arguments and experimental evidence from the literature are used to determine the relationship between the viscosity, η, and chain radius of gyration,RG. The viscosity-radius of gyration relationship is found to be$${\boldsymbol{\eta }}{\boldsymbol{ \sim }}{{\boldsymbol{R}}}_{{\boldsymbol{G}}}^{{\boldsymbol{m}}{\boldsymbol{(}}\dot{{\boldsymbol{\gamma }}}{\boldsymbol{)}}}$$η~RGm(γ˙)where m($$\dot{{\boldsymbol{\gamma }}}$$γ˙) is the power law exponent of the viscosity-temperature relationship that depends on the specific polymer-solvent system and the shear rate,$$\dot{{\boldsymbol{\gamma }}}$$γ˙. The viscosity is shown to be a power law function of the radius, and to decrease with decreasing radius under conditions where the chains are ideal random walks in concentrated solution. Furthermore, this relationship is consistent with both the widely observed viscosity-temperature and viscosity-shear rate behavior observed in polymer rheology. The assumption of extension is not consistent with these observations as it would require that the chains increase in size with increasing temperature. Shear thinning is thus a result of a decreasing radius with increasing shear rate as$${{\boldsymbol{R}}}_{{\boldsymbol{G}}} \sim {\dot{{\boldsymbol{\gamma }}}}^{-{\boldsymbol{n}}{\boldsymbol{/}}{\boldsymbol{m}}{\boldsymbol{(}}\dot{{\boldsymbol{\gamma }}}{\boldsymbol{)}}}$$RG~γ˙−n/m(γ˙)where n is the power law exponent. Furthermore, the thermal expansion coefficients determine the variation in the power law exponents that are measured for different polymer systems. Typical values of n enable the measured reduction in coils size behavior to be fitted. Furthermore, the notion that polymer chains extend to reduce the viscosity implies that an increasing chain size results in a reduced viscosity is addressed. This assumption would require that the viscosity increases with reducing coil radius which is simply unphysical.
Chemically defined conditions for long-term maintenance of pancreatic progenitors derived from human induced pluripotent stem cells
Authors: Konagaya Shuhei , Iwata Hiroo
Published: January 2019

Large numbers of hormone-releasing cells, approximately 109 endocrine cells, are required to treat type I diabetes patients by cell transplantation. The SOX9-positive pancreatic epithelium proliferates extensively during the early stages of pancreatic development. SOX9-positive pancreatic epithelium is thought to be an expandable cell source of β cells for transplantation therapy. In this study, we attempted to expand pancreatic progenitors (PPs: PDX1+/SOX9+) derived from four human iPSC lines in three-dimensional (3D) culture using a chemically defined medium and examined the potential of the derived PPs to differentiate into β-like cells. PPs from four human iPSC lines were maintained and effectively proliferated in a chemically defined medium containing epidermal growth factor and R-spondin-1, CHIR99021, fibroblast growth factor-7, and SB431542. PPs derived from one iPSC line can be expanded by more than 104-fold in chemically defined medium containing two of the fives, epidermal growth factor and R-spondin-1. The expanded PPs were also stable following cryopreservation. After freezing and thawing, the PPs proliferated without a decrease in the rate. PPs obtained after 50 days of culture successfully differentiated into insulin-positive β-like cells, glucagon-positive α-like cells, and somatostatin-positive δ-like cells. The differentiation efficiency of expanded PPs was similar to that of PPs without expansion culture.
Polygenic impact of common genetic risk loci for Alzheimer’s disease on cerebral blood flow in young individuals
Authors: Chandler Hannah L. , Wise Richard G. , Murphy Kevin , Tansey Katherine E. , Linden David E. J. , Lancaster Thomas M.
Published: January 2019

Genome-wide association studies (GWAS) show that many common alleles confer risk for developing Alzheimer’s disease (AD). These risk loci may contribute to MRI alterations in young individuals, preceding the clinical manifestations of AD. Prior evidence identifies vascular dysregulation as the earliest marker of disease progression. However, it remains unclear whether cerebrovascular function (measured via grey-matter cerebral blood flow (gmCBF)) is altered in young individuals with increased AD genetic risk. We establish relationships between gmCBF with APOE and AD polygenic risk score in a young cohort (N = 75; aged: 19–32). Genetic risk was assessed via a) possessing at least one copy of the APOE ɛ4 allele and b) a polygenic risk score (AD-PRS) estimated from AD-GWAS. We observed a reduction in gmCBF in APOE ɛ4 carriers and a negative relationship between AD-PRS and gmCBF. We further found regional reductions in gmCBF in individuals with higher AD-PRS across the frontal cortex (PFWE < 0.05). Our findings suggest that a larger burden of AD common genetic risk alleles is associated with attenuated cerebrovascular function, during young adulthood. These results suggest that cerebral vasculature is a mechanism by which AD risk alleles confer susceptibility.