bluuebunny/crossref_metadata_2025 huggingface dataset:
Electronic circular dichroism and nuclear magnetic resonance studies of peptides derived from the FKBP52‐interacting β‐turn of the hERα ligand‐binding domain
Authors: Byrne Cillian , Belnou Mathilde , Baulieu Etienne‐Emile , Lequin Olivier , Jacquot Yves
Published: January 2019

When located at the surface of proteins, turns containing a Pro‐Gly (PG) motif are often involved in protein/protein interactions and may participate in intracellular signaling cascades. As such, conformationally constrained short protein‐derived turn peptides offer promising perspectives for the development of drug candidates in the context of interfering with protein/protein interactions. From X‐ray crystal structures of the human estrogen receptor α ligand‐binding domain (hERα‐LBD), we have identified a short peptide motif (residues 363‐367, sequence: RVPGF) that adopts a type II β‐turn and which is a substrate of the FK1 peptidyl‐prolyl cis‐trans isomerase (PPIase or rotamase) catalytic site of the immunophilin FKBP52, when synthesized independently from the protein. Using ECD and NMR spectroscopy in combination with molecular dynamics simulations, we have embarked on a conformational study of peptides derived from this sequence, and we have explored the effects resulting from N‐ and C‐termini chemical modifications, cyclization, as well as from the replacement of both the proline and its preceding residue by various natural and non‐natural amino acids. All peptides are found to explore several conformational states in aqueous solution, differing by the conformation of the peptide bond preceding the proline residue of the central VPG segment. Trans isomers are characterized by a conformational equilibrium between a type II β‐turn around PG and an extended conformation, while cis isomers adopt a type VIb β‐turn centered on the Xaa‐Pro segment. We show here how limited chemical modifications can deeply influence the turn conformation of this FKBP52‐interacting peptide.
Effects of different odours on the reproductive success of Mus musculus as an alternative method of control
Authors: Adduci Luciana B , León Vanina A , Busch María , Fraschina Jimena
Published: January 2019

BACKGROUND

The house mouse (Mus musculus) is a cosmopolitan rodent that has become adapted to living in close association with humans and is considered a serious pest because it poses a risk to human health, and causes economic losses due to food and crop consumption and damage to buildings. Its control in livestock farms is achieved mainly through the application of anticoagulant rodenticides, but the effect of these compounds is limited due to the presence of resistant individuals and aversive behaviours. A potential alternative method is the use of chemical signals to reduce rodent reproductive success. In this study, we assessed the effects of odours from an unfamiliar male, 17β‐oestradiol, overcrowding, cat urine and 2,5‐dihydro‐2,4,5‐trimethylthiazoline (TMT) on the reproductive success of laboratory Mus musculus females.

RESULTS

According to the generalized linear mixed models, cat urine odour increased the proportion of abortions per female, unfamiliar male odour decreased the mean number of offspring born per female, and TMT had an overall negative effect on mean offspring production at birth and at weaning. The other odours had no significant effects on reproductive success.

CONCLUSIONS

TMT seems to be the best candidate for population control because it caused a decrease in the mean number of offspring born and the mean number of live offspring at weaning. TMT also has the advantage of being available in commercial forms. To be useful for rodent management in field conditions, these results should be confirmed using wild house mice females. © 2019 Society of Chemical Industry
Spatiotemporal dynamics of fungicide resistance in the wheat pathogen Zymoseptoria tritici in France
Authors: Garnault Maxime , Duplaix Clémentine , Leroux Pierre , Couleaud Gilles , Carpentier Florence , David Olivier , Walker Anne‐Sophie
Published: January 2019

BACKGROUND

Management of pesticide resistance is a major issue in modern agricultural systems, particularly in the context of the broader challenge of reducing pesticide use. However, such management must be adapted to resistance dynamics, which remains challenging to predict due to its dependence on many biological traits of pests, interactions with the environment and pesticide use. We retrospectively studied the evolution of reported resistances to four modes of action (benzimidazoles, quinone outside inhibitors, sterol demethylation inhibitors and succinate dehydrogenase inhibitors), in French populations of the wheat pathogen Zymoseptoria tritici.

RESULTS

We used statistical models to analyse the Performance trial network data set (2004–2017; ∼ 70 locations in France yearly). They highlighted contrasting behaviours between phenotypes, for example: (i) stable spatial distributions and colonization front structures over time, and (ii) different frequency growth rates at the national scale and between regions.

CONCLUSION

We provide a quantitative description of the spatiotemporal patterns of resistance evolution for fungicides with several modes of action. Moreover, we highlight some unexpected resistance dynamics in France, with major differences between the north and south. This complex pattern of resistance evolution in French populations is consistent with previous descriptions of dynamics at the European scale. These results should make it easier to anticipate evolution locally and to improve the management of resistance. © 2019 Society of Chemical Industry
Blood‐Based Biomarkers of Quinpirole Pharmacology: Cluster‐Based PK/PD and Metabolomics to Unravel the Underlying Dynamics in Rat Plasma and Brain
Authors: van den Brink Willem J. , Hartman Robin , van den Berg Dirk‐Jan , Flik Gunnar , Gonzalez‐Amoros Belén , Koopman Nanda , Elassais‐Schaap Jeroen , van der Graaf Piet Hein , Hankemeier Thomas , de Lange Elizabeth C.M.
Published: January 2019

A key challenge in the development of central nervous system drugs is the availability of drug target specific blood‐based biomarkers. As a new approach, we applied cluster‐based pharmacokinetic/pharmacodynamic (PK/PD) analysis in brain extracellular fluid (brainECF) and plasma simultaneously after 0, 0.17, and 0.86 mg/kg of the dopamine D2/3 agonist quinpirole (QP) in rats. We measured 76 biogenic amines in plasma and brainECF after single and 8‐day administration, to be analyzed by cluster‐based PK/PD analysis. Multiple concentration‐effect relations were observed with potencies ranging from 0.001–383 nM. Many biomarker responses seem to distribute over the blood‐brain barrier (BBB). Effects were observed for dopamine and glutamate signaling in brainECF, and branched‐chain amino acid metabolism and immune signaling in plasma. Altogether, we showed for the first time how cluster‐based PK/PD could describe a systems‐response across plasma and brain, thereby identifying potential blood‐based biomarkers. This concept is envisioned to provide an important connection between drug discovery and early drug development.
Balance free speech with students' use of logos
Authors: McCarthy Claudine
Published: January 2019

When students use an institution's name or other identifying marks to create art, T‐shirts, logos, and the like for their club, group, or cause, many student affairs professionals don't know how to properly reconcile protecting the institution's brand with protecting students' free speech rights.
Balance innovation, risk management amidst change
Authors: McCarthy Claudine
Published: January 2019

Cedric B. Howard, Ed.D., considers facilitating change both his greatest challenge and the most rewarding aspect of his 23‐year higher ed career. That perspective has helped to pave the way to success for Howard, who as vice president for enrollment and student services at SUNY Fredonia was recently named one of NASPA's Pillars of the Profession.
Mesenchymal Stem Cells from Chronic Pancreatitis Patients Show Comparable Potency Compared to Cells from Healthy Donors
Authors: Wang Jingjing , Zhang Yong , Cloud Colleen , Duke Tara , Owczarski Stefanie , Mehrotra Shikhar , Adams David B. , Morgan Katherine , Gilkeson Gary , Wang Hongjun
Published: January 2019

Mesenchymal stem cells (MSCs) are proven to be beneficial in islet transplantation, suggesting a potential therapeutic role of them in total pancreatectomy with islet autotransplantation (TP-IAT) for chronic pancreatitis (CP) patients. We investigated whether MSCs derived from CP patients are suitable for use in autologous cell therapy. MSCs from healthy donors (H-MSCs) and CP patients (CP-MSCs) were studied for phenotype, colony formation potential, multilineage differentiation ability, proliferation, senescence, secretory characters, and immunosuppressive functions. The potential protective effect of CP-MSCs was evaluated on hypoxia-induced islet cell death. Cell surface markers were similar between H-MSCs and CP-MSCs, as well as the ability of colony formation, multilineage differentiation, secretion of vascular endothelial growth factor and transforming growth factor (TGF-β), senescence, and inhibition of T cells proliferation in vitro. We found that growth differentiation factor 6 and hepatocyte growth factor (HGF) were significantly downregulated, whereas TGFβ and matrix metalloproteinase-2 were significantly upregulated in CP-MSCs compared with H-MSCs, among 84 MSC-related genes investigated in this study. MSCs from CP patients secreted less HGF, compared with the H-MSCs. A higher interferon-γ-induced indoleamine 2,3-dioxygenase expression was observed in CP-MSCs compared to H-MSCs. Moreover, CP-MSCs prevented hypoxia-induced β cell deaths to a similar extent as H-MSCs. Regardless of moderate difference in gene expression, CP-MSCs possess similar immunomodulatory and prosurvival functions to H-MSCs, and may be suitable for autologous cell therapy in CP patients undergoing TP-IAT. Stem Cells Translational Medicine  2019;8:418–429
Electrodeposition of Silver Nanoparticles on Reduced Graphene Functionalized by Pyridine‐Pyridazine Units: Application to Surface‐Enhanced Raman Spectroscopy and Electrocatalysis
Authors: Rus Yahdi Bin , Galmiche Laurent , Audebert Pierre , Courty Alexa , Maisonhaute Emmanuel , Miomandre Fabien
Published: January 2019

A new and versatile method to prepare Ag nanoparticles on functionalized graphene sheets is described. In a first step, pyridine‐pyridazine units are introduced on graphene sheets by cycloaddition reaction with a tetrazine derivative. Then the material is coated on an electrode and electrodeposition is carried out to generate silver nanoparticles in a one‐step electroreduction process. The applied potential signal is shown to influence the size and dispersity of the particles in the composite. While larger particles are active in improving sensitivity of Surface‐Enhanced Raman Spectroscopy, smaller ones can be efficiently used in electrocatalysis, like for oxygen reduction. Both effects are demonstrated to highlight the versatility of the applications of these easily prepared nanocomposites.
Dissipation of Pyrene‐Based Phenylboronic Acid‐Anchored Vesicular Self‐Assemblies: A Motif for Neurotransmitter Recognition
Authors: Mandal Deep , Das Suman
Published: January 2019

The present article delineates an elegant strategy to develop vesicular self‐assembly based bio‐molecule recognition motif to sense particular class of neuro‐chemicals. Pyrene based phenylboronic acid (PBA) tailored amphiphiles were synthesized that formed vesicular self‐assemblies in aqueous solution. Molecular aggregation patterns and various non‐covalent forces involved in the vesiculation process were analysed through microscopy‐based and spectroscopic techniques. The incorporation of PBA functionality in the amphiphilic backbone rendered di‐ol sensitivity within the vesicular structures owing to its high affinity to bind reversibly with di‐ol (catechol) moieties. Interestingly, the vesicular self‐assemblies exhibited enhanced fluorescence signals in response to miniscule amounts of catecholamine‐class neurotransmitters (dopamine, adrenaline, and noradrenaline) including L‐3,4‐dihydroxyphenylalanine (L–DOPA). Moreover, the vesicular aggregates underwent dissipation in presence of L–DOPA. This dissolution of well‐ordered molecular arrangement along with fluorescence enhancement took place due to the probable formation of boronate‐diol adduct. The soft materials failed to exhibit any physico‐chemical change in the presence of other neuro‐chemicals devoid of a catechol moiety. Thus, the di‐ol induced dissipation and fluorescent augmentation feature of the PBA tethered vesicular aggregates hoisted the soft‐material as proficient bio‐marker for catecholamine class neurotransmitters.
Luminol‐Pendant Chemiluminescent Polymethacrylamide‐Based Polymers for Peroxide Sensing in Live Cell Imaging.
Authors: Deepa Simon , Rajendrakumar Kannapiran
Published: January 2019

The present study aims at the development of luminol pendant functionalized chemiluminescent polymethacrylamides, for sensing and imaging applications. Luminol functionalized poly(methacrylamide) homopolymer was synthesized by the post‐polymerization modification of poly(methacryloyl chloride), (PMC) with luminol. Luminol based methacrylamide monomer (LUME) was synthesized using a simple Schotten‐Baumann type reaction between methacryloyl chloride and luminol. LUME was copolymerized with hydroxyethyl methacrylate (HEMA) using SET‐LRP (Single Electron Transfer‐ Living Radical Polymerization), a controlled radical polymerization technique. Luminol functionalized homo (PML) and copolymer (PHL) were having excellent solubility in basic medium as well as polar solvents like as dimethyl sulfoxide and dimethyl formamide. Basic solutions of both PML and PHL copolymers were tested for their chemiluminescent sensing of hydrogen peroxide using graphene oxide (GO) as a catalyst. Chemiluminescence intensity was found to be varying linearly with an increase in the concentration of hydrogen peroxide for both these polymers. Upto 1 μM of peroxide can be sensed even with a very dilute solution of PML (1.8x10−11M) and PHL (2x10−8M).These chemiluminescent polymethacrylamides were also studied for peroxide sensing in live cells.
Synthesis of New Porphyrin Complexes: Evaluations on Optical, Electrochemical, Electronic Properties and Application as an Optical Sensor
Authors: Brahmi Jihed , Nasri Soumaya , Saidi Hamza , Nasri Habib , Aouadi Kaiss
Published: January 2019

This work reports on the synthesis, characterization and application as an optical sensor of two new porphyrin complexes namely :(Hexamethylenetetramine)(meso‐tetratrifluoromethylphenylporphyrinato) zinc(II) [Zn(TFMPP)(HMTA)] and (Hexamethylenetetramine)(meso‐tetra‐tert‐butylphenylphenylporphyrinato) Zinc(II) [Zn(TtBuPP)(HMTA)]. The chemical structures of these species were defined by 1HNMR and FT‐IR spectroscopic analysis. The optical properties of these π‐conjugated systems were investigated by UV‐visible, absorption and photoluminescence spectroscopy. The UV‐visible titrations show that the Soret and Q bands of the new complexes are red‐shifted compared to those of the starting material species [Zn(TFMPP)] and [Zn(TtBuPP)] and the association constants (Kas) was found to be depending on the withdrawing‐donating effects of the substituents on the phenyls ring of the meso‐porphyrins. The electrochemical behavior was also investigated and the optical and electrochemical energy gaps were determinate. The electronic properties of the ITO/Pi/Al have been defined by I–V characteristics and impedance spectroscopy measurements.
Syntheses and Structures of Group 10 Metal POCOP Pincer Complexes Bearing A Mercapto‐o–carborane Auxiliary Ligand
Authors: Zhang Jie , Cao Bula , Ding Yazhou , Chang Jiarui , Li Shujun , Chen Xuenian
Published: January 2019

Several bis(phosphinite) (POCOP) group 10 metal pincer complexes bearing a mercapto‐o‐carborane auxiliary ligand, [2,6‐(iPr2PO)2C6H3]MS‐o‐C2B10H11 (M=Ni, 1; Pd, 2; Pt, 3), were synthesized and fully characterized. Single crystal X‐ray diffraction analyses indicated that the square planar geometries of the metal centers and the POCOP pincer backbones were not significantly distorted. However, relatively weak M−S bonds were observed for all of these complexes in the solid state and a remarkable small Pt‐Cipso coupling constant (116 Hz) was detected for complex 3 during the NMR study, implying a weak Pt‐Cipso interaction in solutions. Despite the weak M−S bonds and the faint M–Cipso interaction, these complexes are relatively stable because of the steric effect of the bulky auxiliary ligand. The stability of these boron‐rich group 10 metal pincer complexes makes them potentially useful in material science.
Effect of the Degree of Inversion on the Electrical Conductivity of Spinel ZnFe2O4
Authors: Granone Luis I. , Dillert Ralf , Heitjans Paul , Bahnemann Detlef W.
Published: January 2019

Spinel ferrites (MFe2O4, where M is a metal ion) in general, and zinc ferrite (ZnFe2O4, ZFO) in particular, have recently received considerable attention due to promising results in the field of photocatalysis and, especially, photoelectrochemistry. ZFO exhibits a variable crystal structure in which the distribution of the cations between octahedral and tetrahedral sites in the cubic close‐packed oxygen lattice, i. e., the degree of inversion, is known to depend closely on the synthetic conditions. Although the effect on the magnetic and optical properties is well known, fundamental research is still missing to fully understand the impact of the cation distribution on the photoelectrochemical activity. In this context, an utmost important physicochemical property is the electrical conductivity. In this work, the dielectric properties of ZFO samples with degrees of inversion ranging from 0.07 to 0.20 were investigated. The conductivity of the ZFO samples was found to increase as the degree of inversion increases. At an onset value of the degree of inversion between 0.13 and 0.16, the bulk conductivity increases by two orders of magnitude. This increase is a direct evidence of the high impact of the cation arrangement in the crystal lattice on the electronic properties of ZFO.
Black Phosphorus, a Rising Star 2D Nanomaterial in the Post‐Graphene Era: Synthesis, Properties, Modifications, and Photocatalysis Applications
Authors: Li Bisheng , Lai Cui , Zeng Guangming , Huang Danlian , Qin Lei , Zhang Mingming , Cheng Min , Liu Xigui , Yi Huan , Zhou Chengyun , Huang Fanglong , Liu Shiyu , Fu Yukui
Published: January 2019

Semiconductor photocatalysis, a sustainable and renewable technology, is deemed to be a new path to resolve environmental pollution and energy shortage. The development of effective photocatalysts, especially the metal‐free photocatalysts, is a critical determinant of this technique. The recently emerged 2D material of black phosphorus with distinctive properties of tunable direct bandgap, ultrahigh charge mobility, fortified optical absorption, large specific surface area, and anisotropic structure has captured enormous attention since the first exfoliation of bulk black phosphorus into mono‐ or few layered phosphorene in 2014. In this article, the state‐of‐the‐art preparation methods are first summarized for bulk black phosphorus, phosphorene, and black phosphorus quantum dot and then the fundamental structure and electronic and optical properties are analyzed to evaluate its feasibility as a metal‐free photocatalyst. Various modifications on black phosphorus are also summarized to enhance its photocatalytic performance. Furthermore, the multifarious applications such as solar to energy conversion, organic removal, disinfection, nitrogen fixation, and photodynamic therapy are discussed and some of the future challenges and opportunities for black phosphorus research are proposed. This review reveals that the rising star of black phosphorus will be a multifunctional material in the postgraphene era.
Polyethylenimine Expanded Graphite Oxide Enables High Sulfur Loading and Long‐Term Stability of Lithium–Sulfur Batteries
Authors: Huang Xia , Zhang Kai , Luo Bin , Hu Han , Sun Dan , Wang Songcan , Hu Yuxiang , Lin Tongen , Jia Zhongfan , Wang Lianzhou
Published: January 2019

To realize practical lithium–sulfur batteries (LSBs) with long cycling life, designing cathode hosts with a high specific surface area (SSA) is recognized as an efficient way to trap the soluble polysulfides. However, it is also blamed for diminishing the volumetric energy density and being susceptible to side reactions. Herein, polyethylenimine intercalated graphite oxide (PEI‐GO) with a low SSA of 4.6 m2 g−1 and enlarged interlayer spacing of 13 Å is proposed as a superior sulfur host, which enables homogeneous distribution of high sulfur content (73%) and facilitates Li+ transfer in thick sulfur electrode. LSBs with a moderate sulfur loading (3.4 mg S cm−2) achieve an initial capacity of 1157 and 668 mAh g−1 after 500 cycles at 0.5 C. Even when the sulfur loading is increased to 7.3 mg cm−2, the electrode still delivers a high areal capacity of 4.7 mAh cm−2 (641 mAh g−1) after 200 cycles at 0.2 C. The excellent electrochemical properties of PEI‐GO are mainly attributed to the homogeneous distribution of sulfur in PEI‐GO and the strong chemical interactions between polysulfides and amine groups, which can mitigate the loss of active phases and contribute to the better cycling stability.
Entanglement versus entwinement in symmetric product orbifolds
Authors: Balasubramanian Vijay , Craps Ben , De Jonckheere Tim , Sárosi Gábor
Published: January 2019

Abstract

We study the entanglement entropy of gauged internal degrees of freedom in a two dimensional symmetric product orbifold CFT, whose configurations consist of N strands sewn together into “long” strings, with wavefunctions symmetrized under permutations. In earlier work a related notion of “entwinement” was introduced. Here we treat this system analogously to a system of N identical particles. From an algebraic point of view, we point out that the reduced density matrix on k out of N particles is not associated with a subalgebra of operators, but rather with a linear subspace, which we explain is sufficient. In the orbifold CFT, we compute the entropy of a single strand in states holographically dual in the D1/D5 system to a conical defect geometry or a massless BTZ black hole and find a result identical to entwinement. We also calculate the entropy of two strands in the state that represents the conical defect; the result differs from entwinement. In this case, matching entwinement would require finding a gauge-invariant way to impose continuity across strands.
A method to determine |Vcb| at the weak scale in top decays at the LHC
Authors: Harrison P. F. , Vladimirov V.E.
Published: January 2019

Abstract

Until now, the Cabibbo Kobayashi Maskawa matrix element, |V

cb
|, has always been measured in B decays, i.e. at an energy scale

$$ {q}_b\sim \frac{m_b}{2} $$

q
b

∼

m
b

2

, far below the weak scale. We consider here the possibility of measuring it close to the weak scale, at q

W
∼ m

W
, in top decays at the Large Hadron Collider (LHC). Our proposed method would use data from the LHC experiments in hadronic top decays

$$ t\to b{W}^{+}\to b\overline{b}c $$

t
→
b

W
+

→
b

b
¯

c

, tagged by the semileptonic decay of the associated top. We estimate the uncertainty of such a measurement, as a function of present and potential future experimental jet flavour-tagging performances, and conclude that first measurements using the data collected during 2016-2018 could yield a fractional error on |V

cb
| of order 7% per experiment. We also give projected performances at higher luminosities, representative of those anticipated at LHC Run 3 and HL-LHC.
Psychosocial risk factors for suicidality in children and adolescents
Authors: Carballo J. J. , Llorente C. , Kehrmann L. , Flamarique I. , Zuddas A. , Purper-Ouakil D. , Hoekstra P. J. , Coghill D. , Schulze U. M. E. , Dittmann R. W. , Buitelaar J. K. , Castro-Fornieles J. , Lievesley K. , Santosh Paramala , Arango C. ,   the STOP Consortium, Sutcliffe Alastair , Curran Sarah , Selema Laura , Flanagan Robert , Craig Ian , Parnell Nathan , Yeboah Keren , Sala Regina , Singh Jatinder , Fiori Federico , Pupier Florence , Vinkenvleugel Loes , Glennon Jeffrey , Bakker Mireille , Drent Cora , Bloem Elly , Steenhuis Mark-Peter , Berg Ruth , Häge Alexander , Dau Mahmud Ben , Mechler Konstantin , Rauscher Sylke , Aslan Sonja , Schlanser Simon , Keller Ferdinand , Schneider Alexander , Plener Paul , Fegert Jörg M. , Paton Jacqui , Macey Murray , Iessa Noha , Alfred Kolozsvari , Helen Furse , Nick Penkov , Baillon Claire , Peyre Hugo , Cohen David , Bonnot Olivier , Brunelle Julie , Franc Nathalie , Raysse Pierre , Humbertclaude Véronique , Rodriguez-Quiroga Alberto , Díaz-Caneja Covadonga Martínez , Espliego Ana , Merchán Jessica , Tapia Cecilia , Baeza Immaculada , Romero Soledad , La Fuente Amalia , Ortiz Ana , Pintor Manuela , Ligas Franca , Cera Francesca Micol , Frongia Roberta , Falissard Bruno , Schwalber Ameli , Dittrich Juliane , Wohner Andrea , Zimmermann Katrin , Schwalber Andrea , Aitchison Katherine
Published: January 2019

Suicidality in childhood and adolescence is of increasing concern. The aim of this paper was to review the published literature identifying key psychosocial risk factors for suicidality in the paediatric population. A systematic two-step search was carried out following the PRISMA statement guidelines, using the terms ‘suicidality, suicide, and self-harm’ combined with terms ‘infant, child, adolescent’ according to the US National Library of Medicine and the National Institutes of Health classification of ages. Forty-four studies were included in the qualitative synthesis. The review identified three main factors that appear to increase the risk of suicidality: psychological factors (depression, anxiety, previous suicide attempt, drug and alcohol use, and other comorbid psychiatric disorders); stressful life events (family problems and peer conflicts); and personality traits (such as neuroticism and impulsivity). The evidence highlights the complexity of suicidality and points towards an interaction of factors contributing to suicidal behaviour. More information is needed to understand the complex relationship between risk factors for suicidality. Prospective studies with adequate sample sizes are needed to investigate these multiple variables of risk concurrently and over time.
Regulation by competition: a hidden layer of gene regulatory network
Authors: Wei Lei , Yuan Ye , Hu Tao , Li Shuailin , Cheng Tianrun , Lei Jinzhi , Xie Zhen , Zhang Michael Q. , Wang Xiaowo
Published: January 2019

Background

Molecular competition brings about trade‐offs of shared limited resources among the cellular components, and thus introduces a hidden layer of regulatory mechanism by connecting components even without direct physical interactions. Several molecular competition scenarios have been observed recently, but there is still a lack of systematic quantitative understanding to reveal the essence of molecular competition.

Methods

Here, by abstracting the analogous competition mechanism behind diverse molecular systems, we built a unified coarse‐grained competition motif model to systematically integrate experimental evidences in these processes and analyzed general properties shared behind them from steady‐state behavior to dynamic responses.

Results

We could predict in what molecular environments competition would reveal threshold behavior or display a negative linear dependence. We quantified how competition can shape regulator‐target dose‐response curve, modulate dynamic response speed, control target expression noise, and introduce correlated fluctuations between targets.

Conclusions

This work uncovered the complexity and generality of molecular competition effect as a hidden layer of gene regulatory network, and therefore provided a unified insight and a theoretical framework to understand and employ competition in both natural and synthetic systems.
The ARIAH-RIHA Professional Exchange Fellowship: first-hand perceptions of photo archives in London art libraries
Authors: Binkowski Kraig
Published: January 2019

In the spring of 2017 I was fortunate enough to receive the ARIAH-RIHA Professional Exchange Fellowship that allowed me to travel to London and conduct research there for a month. While in London I looked closely at the collections, services, and clientele of several important art libraries in London but the main focus of my investigation was the photo archive collections that make up a part of many of these art libraries. The photo archives in my own institution at the Yale Center for British Art and our efforts toward digitisation, discovery, and open access made my close examination of similar collections in London particularly relevant – I wished to see how these libraries approached similar challenges and if these institutions share a common understanding of photo archives.
Facilitating the development of creativity using special collections and archives
Authors: Ruthven Lesley
Published: January 2019

How can special collections and archives (SCA) services contribute to the development of creativity in higher education students? An understanding of how creativity is developed can help those who work with special collections and archives to better design sessions that facilitate this development. Creativity is defined, put in context, and discussed as a metacognitive process. SCA as an environment that can contribute to the development of creativity is explored, along with the importance of the learner voice and pedagogical tools that allow for the facilitation of metacognitive experiences.
Tracking vortex surfaces frozen in the virtual velocity in non-ideal flows
Authors: Hao Jinhua , Xiong Shiying , Yang Yue
Published: January 2019

We demonstrate that, if a globally smooth virtual circulation-preserving velocity exists, Kelvin’s and Helmholtz’s theorems can be extended to some non-ideal flows which are viscous, baroclinic or with non-conservative body forces. Then we track vortex surfaces frozen in the virtual velocity in the non-ideal flows, based on the evolution of a vortex-surface field (VSF). For a flow with a viscous-like diffusion term normal to the vorticity, we obtain an explicit virtual velocity to accurately track vortex surfaces in time. This modified flow is dissipative but prohibits reconnection of vortex lines. If a globally smooth virtual velocity does not exist, an approximate virtual velocity can still facilitate the tracking of vortex surfaces in non-ideal flows. In a magnetohydrodynamic Taylor–Green flow, we find that the conservation of vorticity flux is significantly improved in the VSF evolution convected by the approximate virtual velocity instead of the physical velocity, and the spurious vortex deformation induced by the Lorentz force is eliminated.
On the decay of dispersive motions in the outer region of rough-wall boundary layers
Authors: Meyers Johan , Ganapathisubramani Bharathram , Cal Raúl Bayoán
Published: January 2019

In rough-wall boundary layers, wall-parallel non-homogeneous mean-flow solutions exist that lead to so-called dispersive velocity components and dispersive stresses. They play a significant role in the mean-flow momentum balance near the wall, but typically disappear in the outer layer. A theoretical framework is presented to study the decay of dispersive motions in the outer layer. To this end, the problem is formulated in Fourier space, and a set of governing ordinary differential equations per mode in wavenumber space is derived by linearizing the Reynolds-averaged Navier–Stokes equations around a constant background velocity. With further simplifications, analytically tractable solutions are found consisting of linear combinations of $\exp (-kz)$ and $\exp (-Kz)$, with $z$ the wall distance, $k$ the magnitude of the horizontal wavevector $\boldsymbol{k}$, and where $K(\boldsymbol{k},Re)$ is a function of $\boldsymbol{k}$ and the Reynolds number $Re$. Moreover, for $k\rightarrow \infty$ or $k_{1}\rightarrow 0$ (with $k_{1}$ the stream-wise wavenumber), $K\rightarrow k$ is found, in which case solutions consist of a linear combination of $\exp (-kz)$ and $z\exp (-kz)$, and are independent of the Reynolds number. These analytical relations are compared in the limit of $k_{1}=0$ to the rough boundary layer experiments by Vanderwel & Ganapathisubramani (J. Fluid Mech., vol. 774, 2015, R2) and are in reasonable agreement for $\ell _{k}/\unicode[STIX]{x1D6FF}\leqslant 0.5$, with $\unicode[STIX]{x1D6FF}$ the boundary-layer thickness and $\ell _{k}=2\unicode[STIX]{x03C0}/k$.
A generalization of Krasnosel'skii compression fixed point theorem by using star convex sets
Authors: Lois-Prados Cristina , Rodríguez-López Rosana
Published: January 2019

In the framework of fixed point theory, many generalizations of the classical results due to Krasnosel'skii are known. One of these extensions consists in relaxing the conditions imposed on the mapping, working with k-set contractions instead of continuous and compact maps. The aim of this work if to study in detail some fixed point results of this type, and obtain a certain generalization by using star convex sets.
Nonlocal problems in perforated domains
Authors: Pereira Marcone C. , Rossi Julio D.
Published: January 2019

In this paper, we analyse nonlocal equations in perforated domains. We consider nonlocal problems of the form$f(x) = \int \nolimits _{B} J(x-y) (u(y) - u(x)) {\rm d}y$withxin a perforated domain$\Omega ^\epsilon \subset \Omega $. HereJis a nonsingular kernel. We think about$\Omega ^\epsilon $as a fixed setΩfrom where we have removed a subset that we call the holes. We deal both with the Neumann and Dirichlet conditions in the holes and assume a Dirichlet condition outsideΩ. In the latter case we impose thatuvanishes in the holes but integrate in the whole ℝN(B = ℝN) and in the former we just consider integrals in ℝNminus the holes ($B={\open R} ^N \setminus (\Omega \setminus \Omega ^\epsilon )$). Assuming weak convergence of the holes, specifically, under the assumption that the characteristic function of$\Omega ^\epsilon $has a weak limit,$\chi _{\epsilon } \rightharpoonup {\cal X}$weakly* inL∞(Ω), we analyse the limit as ε → 0 of the solutions to the nonlocal problems proving that there is a nonlocal limit problem. In the case in which the holes are periodically removed balls, we obtain that the critical radius is of the order of the size of the typical cell (that gives the period). In addition, in this periodic case, we also study the behaviour of these nonlocal problems when we rescale the kernel in order to approximate local PDE problems.
Association of the glycaemic index and glycaemic load with colorectal cancer in the population of Córdoba (Argentina): results of a case–control study using a multilevel modelling approach
Authors: Haluszka Eugenia , Dávila Valentina Luciana , Aballay Laura Rosana , Diaz Maria del Pilar , Osella Alberto Rubén , Niclis Camila
Published: January 2019

The glycaemic index (GI) and glycaemic load (GL) are involved in the aetiology of different diseases, and they could be related to the development of colorectal cancer (CRC). The aim of this study was to evaluate the association between the quality and quantity indicators of carbohydrates consumed by the population of Córdoba (Argentina) and the odds of developing CRC in 2008–2016 period. A case–control study was conducted with 492 participants (161/331 cases/controls), interviewed through a validated FFQ. Multilevel logistic regression models were used to assess the effect of GI, GL and the quantity or weekly intake of high-GI foods on CRC occurrence, following adjustment for individual/first-level covariates, and using level of urbanisation as the contextual variable. The models were stratified by sex. Participants in the highestv.lowest tertile of dietary GL and weekly intake of high-GI foods had increased odds of CRC presence in the entire sample (OR 1·64, 95 % CI 1·16, 2·34 and OR 1·11, 95 % CI 1·09, 1·14, respectively) and in women (OR 1·98, 95 % CI 1·24, 3·18 and OR 1·41, 95 % CI 1·09, 1·83, respectively). In men, the second tertile of GL and weekly intake of high-GI foods were associated with CRC (OR 1·44, 95 % CI 1·04, 1·99 and OR 1·48, 95 % CI 1·32, 1·65, respectively). Also, GI was associated with CRC in women (highestv.lowest tertile OR 2·12, 95 % CI 1·38, 3·27). In addition to the quantity and quality of carbohydrates intake, it is important to consider the frequency of consumption of high-GI foods in CRC prevention.
Differences among regions in environmental predictors of primate community similarity affect conclusions about community assembly
Authors: Beaudrot Lydia , Marshall Andrew J.
Published: January 2019

Understanding why ecological communities contain the species they do is a long-standing question in ecology. Two common mechanisms that affect the species found within communities are dispersal limitation and environmental filtering. Correctly identifying the relative influences of these mechanisms has important consequences for our understanding of community assembly. Here variable selection was used to identify the environmental variables that best predict tropical forest primate community similarity in four biogeographic regions: the Neotropics, Afrotropics, Madagascar and the island of Borneo in South-East Asia. The environmental variables included net primary productivity and altitude, as well as multiple temperature, precipitation and topsoil variables. Using the best environmental variables in each region, Mantel and partial Mantel tests were used to reanalyse data from a previously published study. The proportion of variance explained increased for each region. Despite increases, much of the variation remained unexplained for all regions (R2: Africa = 0.45, South America = 0.16, Madagascar = 0.28, Borneo = 0.10), likely due to different evolutionary and biogeographic histories within each region. Nonetheless, substantial variation among regions in the environmental variables that best predicted primate community similarity were documented. For example, none of the 14 environmental variables was included for all four regions, yet each variable was included for at least one region. Contrary to prior results, environmental filtering was an important assembly mechanism for primate communities in tropical forests worldwide. Geographic distance more strongly predicted African and South American communities whereas environmental distance more strongly predicted Malagasy and Bornean communities. These results suggest that dispersal limitation structures primate communities more strongly than environmental filtering in Africa and in South America whereas environmental filtering structures primate communities more strongly than dispersal limitation in Madagascar and Borneo. For communities defined by genera, environmental distance more strongly predicted primate communities than geographic distance in all four regions, which suggests that environmental filtering is a more influential assembly mechanism at the genus level. Therefore, a more nuanced consideration of environmental variables affects conclusions about the influences of environmental filtering and dispersal limitation on primate community structure.
Getting greener by going black: the effect of blacklisting municipalities on Amazon deforestation
Authors: Assunção Juliano , Rocha Romero
Published: January 2019

In 2008, the Brazilian government blacklisted municipalities in the Amazon to better target efforts to repress deforestation. Not only were law enforcement and monitoring activities intensified, but also economic sanctions and political pressures were imposed on those municipalities. We use a differences-in differences approach to compare deforestation reduction in blacklisted municipalities and non-blacklisted municipalities. We find that: (i) the blacklisting has significantly reduced deforestation; and (ii) this effect was primarily driven by the monitoring and law enforcement channel – there is no effect on agricultural production or credit concessions.
“Drugs Don’t Work in Patients Who Don’t Take Them”
Authors: Mechler Konstantin , Häge Alexander
Published: January 2019

Abstract. The more recent term “adherence” is now taking the place of the earlier notion of “compliance,” as it emphasizes the physician-patient partnership. To date, however, it has not been clearly defined. There are many limitations to measuring adherence, and presently no standard methods have been established. Even in clinical trials throughout medicine, the reported rates for adherence range only between 43 % and 78 %. Particularly medication adherence is highly relevant to the treatment of mentally ill adolescents, as they make up a population especially vulnerable to nonadherence – and high rates thereof have been reported. Factors influencing adherence are poorly understood and researched, especially in adolescents with mental illness. Physicians can currently rely only on concepts from other populations and expert recommendations. Concepts for children or adults should not directly be transferred to adolescent patients. Results from the current “SEMA” study should contribute to guiding future research in the development of interventions to improve medication adherence, in particular for this juvenile population.
Halogen Heterogeneity in the Lithosphere and Evolution of Mantle Halogen Abundances Inferred From Intraplate Mantle Xenoliths
Authors: Kobayashi Masahiro , Sumino Hirochika , Burgess Ray , Nakai Shun'ichi , Iizuka Tsuyoshi , Nagao Jun , Kagi Hiroyuki , Nakamura Michihiko , Takahashi Eiichi , Kogiso Tetsu , Ballentine Chris J.
Published: January 2019

We present halogen, noble gas, and major and trace element compositions of mantle xenoliths from intraplate settings (Eifel, Kilbourne Hole, San Carlos, and Hawaii). The xenoliths show a wide range of halogen elemental ratios, which form two arrays centered on the halogen composition of mid‐ocean ridge basalts. The samples on the array toward high I/Cl value have relatively low Cl concentration and low ratios of highly incompatible elements relative to heavy rare earth elements, whereas the samples on the array toward low Br/Cl value have higher Cl concentration and trace elements ratios. The detailed mechanisms to account for these signatures are equivocal at present. However, they are most likely to be related to secondary processes of volatile loss during partial melting and secondary phase formation during interaction with melts. The common primary mid‐ocean ridge basalt‐like halogen ratios in mantle xenoliths from different parts of the globe indicate that the mantle itself must have a relatively uniform composition over a wide scale. The mantle has maintained its halogen composition over billion year timescales without being affected by I‐rich halogens being transported into the mantle. Mass balance calculations suggest that, in order to maintain the I/Cl ratio of the convecting mantle over 2 Gyr, the I/Cl ratio of the subducted halogens must be no more than several times higher than the present‐day mantle value.
Remotely Forced Decadal Physical and Biogeochemical Variability of North Pacific Subtropical Mode Water Over the Last 40 Years
Authors: Oka Eitarou , Yamada Kodai , Sasano Daisuke , Enyo Kazutaka , Nakano Toshiya , Ishii Masao
Published: January 2019

Half‐century‐long observations at the 137°E repeat hydrographic section across the western North Pacific have been analyzed to demonstrate remotely forced decadal physical and biogeochemical variability of Subtropical Mode Water (STMW) over the last 40 years. During unstable periods of the Kuroshio Extension (KE) that lagged the warm phase of the Pacific Decadal Oscillation by 3–4 years, high regional eddy activity reduced the formation rate and salinity of STMW in its main formation region south of the KE. At the 137°E section south of Japan, decreasing southwestward advection of oxygen‐rich STMW from the formation region resulted in decreases of its cross‐sectional area, dissolved oxygen, pH, and aragonite saturation state and increases of nutrients and dissolved inorganic carbon, among which changes of the carbon system parameters accelerated their long‐term trends. Such changes reversed and acidification slowed down during stable‐KE periods, especially in the current period since 2010 exhibiting a hiatus of acidification.
Mantle Transition Zone Structure Beneath Northeast Asia From 2‐D Triplicated Waveform Modeling: Implication for a Segmented Stagnant Slab
Authors: Lai Yujing , Chen Ling , Wang Tao , Zhan Zhongwen
Published: January 2019

The structure of the mantle transition zone (MTZ) in subduction zones is essential for understanding subduction dynamics in the deep mantle and its surface responses. We constructed the P (Vp) and SH velocity (Vs) structure images of the MTZ beneath Northeast Asia based on two‐dimensional (2‐D) triplicated waveform modeling. In the upper MTZ, a normal Vp but 2.5% low Vs layer compared with IASP91 are required by the triplication data. In the lower MTZ, our results show a relatively higher‐velocity layer (+2% Vp and −0.5% Vs compared to IASP91) with a thickness of ~140 km and length of ~1,200 km atop the 660‐km discontinuity. Taking this anomaly as the stagnant slab and considering the plate convergence rate of 7–10 cm/year in the western Pacific region during the late Cenozoic, we deduced that the stagnant slab has a subduction age of less than 30 Ma. This suggests that the observed stagnancy of the slab in the MTZ beneath Northeast Asia may have occurred no earlier than the Early Oligocene. From the constraints derived individually on Vp and Vs structures, high Vp/Vs ratios are obtained for the entire MTZ beneath Northeast Asia, which may imply a water‐rich and/or carbonated environment. Within the overall higher‐velocity stagnant slab, a low‐velocity anomaly was further detected, with a width of ~150 km, Vp and Vs reductions of 1% and 3% relative to IASP91. Such a gap may have provided a passage for hot deep mantle materials to penetrate through the thick slab and feed the Changbaishan volcano.
Hall Receives 2018 David Perlman Award for Excellence in Science Journalism–News
Authors:   AGU
Published: January 2019

Shannon Hall received the David Perlman Award for Excellence in Science Journalism–News at the 2018 AGU Fall Meeting Honors Ceremony, held 12 December 2018 in Washington, D. C. The award recognizes a journalist for “excellence in science news reporting, defined as work prepared with a deadline of one week or less.”
Indigenous Symposium on Water Research, Education, and Engagement
Authors: Chief Karletta , Emanuel Ryan , Conroy-Ben Otakuye
Published: January 2019

Water in the Native World: The Intersection of Hydrology and Indigenous Knowledge; Pablo, Montana, 1–4 August 2018