bluuebunny/crossref_metadata_2025 huggingface dataset:
Methane Feedback on Atmospheric Chemistry: Methods, Models, and Mechanisms
Authors: Holmes Christopher D.
Published: April 2018

The atmospheric methane (CH4) chemical feedback is a key process for understanding the behavior of atmospheric CH4 and its environmental impact. This work reviews how the feedback is defined and used, then examines the meteorological, chemical, and emission factors that control the feedback strength. Geographical and temporal variations in the feedback are described and explained by HOx (HOx = OH + HO2) production and partitioning. Different CH4 boundary conditions used by models, however, make no meaningful difference to the feedback calculation. The strength of the CH4 feedback depends on atmospheric composition, particularly the atmospheric CH4 burden, and is therefore not constant. Sensitivity tests show that the feedback depends very weakly on temperature, insolation, water vapor, and emissions of NO. While the feedback strength has likely remained within 10% of its present value over the industrial era and likely will over the twenty‐first century, neglecting these changes biases our understanding of CH4 impacts. Most environmental consequences per kg of CH4 emissions, including its global warming potential (GWP), scale with the perturbation time, which may have grown as much as 40% over the industrial era and continues to rise.
Signature‐Domain Calibration of Hydrological Models Using Approximate Bayesian Computation: Theory and Comparison to Existing Applications
Authors: Kavetski Dmitri , Fenicia Fabrizio , Reichert Peter , Albert Carlo
Published: April 2018

This study considers Bayesian calibration of hydrological models using streamflow signatures and its implementation using Approximate Bayesian Computation (ABC). If the modeling objective is to predict streamflow time series and associated uncertainty, a probabilistic model of streamflow must be specified but the inference equations must be developed in the signature domain. However, even starting from simple probabilistic models of streamflow time series, working in the signature domain makes the likelihood function difficult or impractical to evaluate (in particular, as it is unavailable in closed form). This challenge can be tackled using ABC, a general class of numerical algorithms for sampling from conditional distributions, such as (but not limited to) Bayesian posteriors given any calibration data. Using ABC does not avoid the requirement of Bayesian inference to specify a probability model of the data, but rather exchanges the requirement to evaluate the pdf of this model (needed to evaluate the likelihood function) by the requirement to sample model output realizations. For this reason ABC is attractive for inference in the signature domain. We clarify poorly understood aspects of ABC in the hydrological literature, including similarities and differences between ABC and GLUE, and comment on previous applications of ABC in hydrology. An error analysis of ABC approximation errors and their dependence on the tolerance is presented. An empirical case study is used to illustrate the impact of omitting the specification of a probabilistic model (and instead using a deterministic model within the ABC algorithm), and the impact of a coarse ABC tolerance.
Eine einfache Methode zur Produktion von Selenoproteinen
Authors: Mukai Takahito , Sevostyanova Anastasia , Suzuki Tateki , Fu Xian , Söll Dieter
Published: April 2018

Ein einfacher Ansatz nutzt einen erweiterten genetischen Code von Escherichia coli zur Biosynthese von Selenoproteinen mit zahlreichen Sec‐Resten. Kürzlich wurden so genannte allo‐tRNAs entdeckt. Diese verfügen über eine ungewöhnliche Struktur, sind genauso effiziente Serinakzeptoren wie die normale tRNASer aus E. coli und werden von der Aeromonas‐salmonicida‐Selenocysteinsynthase (SelA) von Ser‐allo‐tRNA zu Sec‐allo‐tRNA umgesetzt. Anschließend ermöglicht es Sec‐allo‐tRNA, fünf UAG‐Stop‐Codons auf der fdhF‐mRNA für E.‐coli‐Formatdehydrogenase H als Sec zu translatieren und katalytisch aktive E.‐coli‐Formatdehydrogenase mit fünf Sec‐Resten in E. coli zu produzieren. Weiterhin konnte gezeigt werden, dass sich in E. coli durch Kombination genetischer Varianten von allo‐tRNA und SelA mit einem modifizierten Selenstoffwechsel das humane Selenoenzym GPx1 mit über 80 % Sec‐Einbaurate rekombinant produzieren lässt. Beide Beispiele belegen den Wert von allo‐tRNAUTu als molekulare Plattform zur Entwicklung neuartiger Selenoproteine.
Hippocampal gray matter increases following multimodal psychological treatment for combat‐related post‐traumatic stress disorder
Authors: Butler Oisin , Willmund Gerd , Gleich Tobias , Gallinat Jürgen , Kühn Simone , Zimmermann Peter
Published: April 2018

Introduction

Smaller hippocampal volumes are one of the most consistent findings in neuroimaging studies of post‐traumatic stress disorder (PTSD). However, very few prospective studies have assessed changes in hippocampal gray matter prior to and following therapy for PTSD, and no neuroimaging studies to date have longitudinally assessed military populations.

Methods

A pilot study was conducted, assessing patients with combat‐related PTSD with structural MRI. Participants were then assigned either to a treatment group or waiting‐list control group. After the treatment group received multimodal psychological therapy for approximately 6 weeks, both groups completed a second neuroimaging assessment.

Results

Region‐of‐interest analysis was used to measure gray matter volume in the hippocampus and amygdala. There was a group by time interaction; the therapy group (n = 6) showed a significant increase in hippocampal volume and a nonsignificant trend toward an increase in amygdala volume following therapy, while no change was observed in the waiting‐list group (n = 9).

Conclusions

This study provides initial evidence for increases in gray matter volume in the hippocampus in response to therapy for combat‐related PTSD.
An Ambient Temperature Electrolyte with Superior Lithium Ion Conductivity based on a Self‐Assembled Block Copolymer
Authors: Dörr Tobias S. , Pelz Alexander , Zhang Peng , Kraus Tobias , Winter Martin , Wiemhöfer Hans‐Dieter
Published: April 2018

In searching for polymer‐based electrolytes with improved performance for lithium ion and lithium metal batteries, we studied block copolymer electrolytes with high amounts of bis(trifluoromethane)sulfonimide lithium obtained by macromolecular co‐assembly of a poly(isoprene)‐block‐poly(styrene)‐block‐poly(ethylene oxide) and the salt from tetrahydrofuran. Particularly, an ultra‐short poly(ethylene oxide) block of 2100 g mol−1 was applied, giving rise to 2D continuous lamellar microstructures. The macroscopic stability was ensured with major blocks from poly(isoprene) and poly(styrene), which separated the ionic conductive PEO/salt lamellae. Thermal annealing led to high ionic conductivities of 1.4 mS cm−1 at 20 °C with low activation energy and a superior lithium ion transference number of 0.7, accompanied by an improved mechanical stability (storage modulus of up to 107 Pa). With high Li:O ratios >1, we show a viable concept to achieve fast Li+ transport in block copolymers (BCP), decoupled from slow polymer relaxation.
Design and Functional Characterization of Synthetic E3 Ubiquitin Ligases for Targeted Protein Depletion
Authors: Baltz Morgan R. , Stephens Erin A. , DeLisa Matthew P.
Published: April 2018

A number of techniques now exist for decreasing the expression of cellular proteins without the need for genomic modification. One such technique involves engineered protein chimeras that combine the ubiquitination activity of E3 ubiquitin ligases with the binding affinity and substrate specificity of designer binding proteins (DBPs). These chimeras, called “ubiquibodies,” are capable of selectively and controllably steering virtually any protein to the ubiquitin proteasome pathway (UPP) for degradation, making ubiquibodies a powerful addition to the protein knockout toolbox. A distinguishing feature of ubiquibodies is their modularity—simply swapping DBPs can generate a new ubiquibody with specificity for a different substrate protein. Moreover, by employing DBPs that recognize particular protein states (e.g., active versus inactive conformation, mutant versus wild‐type, post‐translational modification), it becomes possible to deplete certain protein subpopulations while sparing others. This protocol outlines the steps necessary to design and functionally evaluate ubiquibodies for customizable silencing of cellular proteins. © 2018 by John Wiley & Sons, Inc.
Modeling VXX
Authors: Gehricke Sebastian A. , Zhang Jin E.
Published: April 2018

In this paper, we study the VXX Exchange Traded Note (ETN), that has been actively traded in recent years, but has lost 99.84% of its value. Using Zhang's formula for VIX futures prices, we develop the first theoretical model for the VXX that links the SPX, VIX, and VXX. We show that the roll yield of VIX futures drives the difference between the VXX and VIX returns. The roll yield is a mostly negative process. We then provide a simple yet robust estimation of the market price of variance risk using VXX and VIX futures prices. The model can be used to price VXX options.
Hippocampal and amygdalar cell‐specific translation is similar soon after stress but diverge over time
Authors: Madan Jesvin S. , Gupta Kanika , Chattarji Sumantra , Bhattacharya Aditi
Published: April 2018

Stress is known to cause contrasting patterns of morphological and physiological plasticity in the hippocampus and amygdala. An obligatory cellular process underlying such neural changes is de novo translation and alterations in protein expression. Yet the nature of the translational response to stress in neurons remains largely unexplored. Even less is known about how glia are affected. Using a click‐chemistry‐based method to label the de novo proteome in live brain slices, we monitored translation in neurons and astrocytes of the basolateral amygdala (BLA) and dorsal hippocampal area CA3 (dCA3) in rats at different time‐points after a single 2‐hr exposure to immobilization stress. We observed enhancements in neuronal translation in both brain regions 1 hour after stress. This initial increase persisted in the BLA up to 10 days afterwards. In contrast, dCA3 neuronal translation gradually decreased to below control levels 10 days later. Translation profiles of dCA3 astrocytes followed timelines similar to neurons, but in BLA astrocytes translation peaked 1 day later and remained elevated 10 days later. Together our results demonstrate that stress causes an immediate upregulation of protein synthesis in both amygdalar and hippocampal neurons and astrocytes. However, these two areas eventually exhibit opposite temporal profiles of protein expression well after the end of stress. These findings identify new metrics of stress‐induced plasticity at the level of cell‐type specific proteomic landscape that may provide important insights into the molecular basis of the divergent temporal effects of stress across brain regions and biological scales.
Data‐driven Evolution Equation Reconstruction for Parameter‐Dependent Nonlinear Dynamical Systems
Authors: Sroczynski David W. , Yair Or , Talmon Ronen , Kevrekidis Ioannis G.
Published: April 2018

When studying observations of chemical reaction dynamics, closed form equations based on a putative mechanism may not be available. Yet when sufficient data from experimental observations can be obtained, even without knowing what exactly the physical meaning of the parameter settings or recorded variables are, data‐driven methods can be used to construct minimal (and in a sense, robust) realizations of the system. The approach attempts, in a sense, to circumvent physical understanding, by building intrinsic “information geometries” of the observed data, and thus enabling prediction without physical/chemical knowledge. Here we use such an approach to obtain evolution equations for a data‐driven realization of the original system – in effect, allowing prediction based on the informed interrogation of the agnostically organized observation database. We illustrate the approach on observations of (a) the normal form for the cusp singularity, (b) a cusp singularity for the nonisothermal CSTR, and (c) a random invertible transformation of the nonisothermal CSTR, showing that one can predict even when the observables are not “simply explainable” physical quantities. We discuss current limitations and possible extensions of the procedure.
Whole‐field macro‐ and micro‐deformation characteristic of unbound water‐loss in dentin hard tissue
Authors: Chen Zhenning , Nadeau Bobby , Yu Kevin , Shao Xinxing , He Xiaoyuan , Goh M. Cynthia , Kishen Anil
Published: April 2018

High‐resolution deformation measurements in a functionally graded hard tissue such as human dentin are essential to understand the unbound water‐loss mediated changes and their role in its mechanical integrity. Yet a whole‐field, 3‐dimensional (3D) measurement and characterization of fully hydrated dentin in both macro‐ and micro‐scales remain to be a challenge. This study was conducted in 2 stages. In stage‐1, a stereo‐digital image correlation approach was utilized to determine the water‐loss and load‐induced 3D deformations of teeth in a sagittal section over consecutively acquired frames, from a fully hydrated state to nonhydrated conditions for a period up to 2 hours. The macroscale analysis revealed concentrated residual deformations at the dentin‐enamel‐junction and the apical regions of root in the direction perpendicular to the dentinal tubules. Significant difference in the localized deformation characteristics was observed between the inner and outer aspects of the root dentin. During quasi‐static loadings, further increase in the residual deformation was observed in the dentin. In stage‐2, dentin microstructural variations induced by dynamic water‐loss were assessed with environmental scanning electron microscopy and atomic force microscopy (AFM), showing that the dynamic water‐loss induced distention of dentinal tubules with concave tubular edges, and concurrent contraction of intertubular dentin with convex profile. The findings from the current macro‐ and micro‐scale analysis provided insight on the free‐water‐loss induced regional deformations and ultrastructural changes in human dentin.
Growth of adsorbed additive layer for further friction reduction
Authors: Hirayama Tomoko , Maeda Masayuki , Sasaki Yuto , Matsuoka Takashi , Komiya Hiroshi , Hino Masahiro
Published: April 2018

Boundary lubrication is one of the most interesting topics in the field of tribology, and a lot of studies have been conducted from the past for understanding the behaviour of boundary lubrication films. General boundary lubrication films are formed by the adsorption of additives mixed into lubricant, and then the tribological performances are drastically improved in many cases. However, there is still room for discussion on the “actual” behaviour of adsorbed additive layer in the tribological condition, that is, under high pressure and/or with external forces. This paper showed the “growing” behaviour of an adsorbed additive layer onto metal surface due to high pressure by means of neutron reflectometry in conjunction with the result obtained through cross‐sectional imaging by frequency‐modulation atomic force microscopy. In addition, the nanotribological study using atomic force microscopy with a colloidal probe showed that the coefficient of friction in the pre‐scratched area was lower than that in the non‐scratched area and that the reduction ratio for lubricant with additive was higher than that for lubricant without additive. This result indicates that growth of the adsorbed additive layer contributed more greatly to a reduction in the coefficient of friction.
Successful management of diabetic ketoacidosis: an innovative protocol
Authors: Phillips Caroline , Sinha Ayush
Published: April 2018

As the prevalence of diabetes increases worldwide, so the numbers of hospital admissions with patients suffering complications, such as diabetic ketoacidosis (DKA), have risen. Morbidity and mortality are affected by delays in presentation and diagnosis, and complications of management. In March 2010, the Joint British Diabetes Societies (JBDS) published national UK guidance on the management of DKA, which was updated in 2013. Both national and local surveys performed since have demonstrated high rates of hypoglycaemia and hypokalaemia, potentially life‐threatening complications.

The West Suffolk Hospital critical care unit guideline incorporates additional safety features to avoid both hypoglycaemia and hypokalaemia, compared with the JBDS guidelines. Retrospective case note review was performed in May 2015 and May 2017 of patients admitted to the critical care unit in the preceding 18 and 15 months meeting the JBDS diagnostic criteria. Our results showed only 15% and 9% of our patients experienced hypoglycaemia, in contrast with 28% in the national DKA survey. While our incidence of hypokalaemia was similar to the national survey, adjustments to our guideline in December 2015 resulted in a marked decrease in the percentage of time spent hypokalaemic by patients on fixed rate intravenous insulin.

We believe there is capacity for improvement of DKA guidelines to reduce the incidence of complications of management, and encourage adjustment of guidelines following our findings. Copyright © 2018 John Wiley & Sons.
Meeting the challenges of housebound patients with diabetes
Authors: Curtis Louise R , Price Hermione C
Published: April 2018

Access to health care is a major determinant of population health, yet the people who need health care the most can be the least able to access it. The housebound are typically a frail group characterised by the potential for dramatic change to their wellbeing after a seemingly minor event. Housebound people with diabetes have been found to have lower rates of access to their nine essential health checks; most notably retinal screening uptake rate is halved in this population.

In response, innovative service redesigns have been described. We are establishing a local inter‐agency collaboration to provide a targeted service specifically for the housebound population with diabetes where all their diabetes care is delivered together. This shared project incorporates three GP surgeries, our local community care team, regional retinal screening provider, local volunteer drivers and befriending charities. The value of working with local charities that are embedded in the community has extended the scope of the service to address the loneliness which is often co‐existent in this expanding patient group. Copyright © 2018 John Wiley & Sons.
Glucocorticoid‐induced diabetes among people without diabetes: a literature review
Authors: Alabbood Majid , Ling Min , Ho Kenneth
Published: April 2018

The effect of glucocorticoid on glycaemic control in people with diabetes has been studied extensively in the literature. However, data regarding its effect on glucose homeostasis in those without diabetes are sparse. This review aims to investigate the incidence of glucocorticoid‐induced diabetes among people without diabetes subjected to high‐dose glucocorticoid, to determine its associated risk factors and to examine the effect of high‐dose glucocorticoid on glucose homeostasis.

Four databases (Ovid Medline, Scopus, Embase, and PubMed) were searched until August 2017 using the following MeSH terms: ‘glucocorticoid*’, ‘dexamethasone’, ‘diabetes mellitus’ and ‘incidence’. Only studies that included the use of high‐dose glucocorticoid (equivalent to 4 mg dexamethasone per day) for at least seven days in their methodology were included.

Nine out of 302 identified studies were included in this review. The incidence of glucocorticoid‐induced diabetes ranged from 1–50%. Pre‐diabetes, age, cumulative dose of glucocorticoid and family history of diabetes were predictors of glucocorticoid‐induced diabetes. The use of high‐dose glucocorticoid aggravated insulin resistance.

Most of the studies were retrospective, and used low‐dose glucocorticoid with a short follow‐up period. The incidence of glucocorticoid‐induced diabetes reported varies widely depending on the type, dose and duration of glucocorticoid, the underlying condition and the presence of established risk factors for diabetes. Further prospective studies testing the effect of glucocorticoid in those without pre‐existing risk factors are required to accurately estimate the incidence of glucocorticoid‐induced diabetes. Copyright © 2018 John Wiley & Sons.
One-modulus Calabi-Yau fourfold reductions with higher-derivative terms
Authors: Grimm Thomas W. , Mayer Kilian , Weissenbacher Matthias
Published: April 2018

Abstract

In this note we consider M-theory compactified on a warped Calabi-Yau four-fold including the eight-derivative terms in the eleven-dimensional action known in the literature. We dimensionally reduce this theory on geometries with one Kähler modulus and determine the resulting three-dimensional Kähler potential and complex coordinate. The logarithmic form of the corrections suggests that they might admit a physical interpretation in terms of one-loop corrections to the effective action. Including only the known terms the no-scale condition in three dimensions is broken, but we discuss caveats to this conclusion. In particular, we consider additional new eight-derivative terms in eleven dimensions and show that they are strongly constrained by compatibility with the Calabi-Yau threefold reduction. We examine their impact on the Calabi-Yau fourfold reduction and the restoration of the no-scale property.
Can INO be sensitive to flavor-dependent long-range forces?
Authors: Khatun Amina , Thakore Tarak , Agarwalla Sanjib Kumar
Published: April 2018

Abstract

Flavor-dependent long-range leptonic forces mediated by the ultra-light and neutral bosons associated with gauged L

e
− L

μ
or L

e
− L

τ
symmetry constitute a minimal extension of the Standard Model. In presence of these new anomaly free abelian symmetries, the SM remains invariant and renormalizable, and can lead to interesting phenomenological consequences. For an example, the electrons inside the Sun can generate a flavor-dependent long-range potential at the Earth surface, which can enhance ν
μ
and

$$ {\overline{\nu}}_{\mu } $$

ν
¯

μ

survival probabilities over a wide range of energies and baselines in atmospheric neutrino experiments. In this paper, we explore in detail the possible impacts of these long-range flavor-diagonal neutral current interactions due to L

e
− L

μ
and L

e
− L

τ
symmetries (one at-a-time) in the context of proposed 50 kt magnetized ICAL detector at INO. Combining the information on muon momentum and hadron energy on an event-by-event basis, ICAL will be sensitive to long-range forces at 90% (3σ) C.L. with 500 kt·yr exposure if the effective gauge coupling α

eμ/eτ

> 1.2 × 10−53 (1.75 × 10−53). The sensitivity of ICAL towards α

eμ
(α

eτ
) is ∼ 46 (53) times better than the existing bound from the Super-Kamiokande experiment at 90% C.L., and at 3σ, the sensitivity of ICAL is comparable to the bounds obtained from the combined solar and KamLAND data.
Electric dipole moments in the minimal scotogenic model
Authors: Abada Asmaa , Toma Takashi
Published: April 2018

Abstract

In this work we consider a minimal version of the scotogenic model capable of accounting for an electron electric dipole moment within experimental sensitivity reach in addition to providing a dark matter candidate and radiatively generating neutrino masses. The Standard Model is minimally extended by two sterile fermions and one inert scalar doublet, both having odd parity, while the Standard Model particles have an even parity, imposed by a ℤ2 symmetry. The neutrino Yukawa couplings provide additional sources of CP violation, and thus a possible impact on electric dipole moments of charged leptons. This model provides two possible dark matter candidates (one bosonic and one fermionic) and our results show that, independently of the ordering of the generated light neutrino spectrum, one can have sizeable electron electric dipole moment within ACME sensitivity reach in the case of fermionic dark matter candidate.
The impact of different land uses in urban area on humus quality
Authors: Oktaba Lidia , Odrobińska Diana , Uzarowicz Łukasz
Published: April 2018

Purpose

In urban areas, humus quantity and quality depend less on natural environmental factors than on anthropogenic ones. The aim of the study was to assess the impact of different land use types of urban soils on the properties of soil organic matter (SOM).

Materials and methods

Thirty-five sites involving four ways of soil use were examined: lawns, allotment gardens, fallows, and arable lands. The study was conducted in Pruszków Town in the Warsaw Agglomeration, Central Poland. Lawns and allotment gardens were located in the central part of the town, whereas fallows and arable lands were in the peripheral zones. Humus horizons, to a depth of 0–20 cm, were analyzed. Using Na-pyrophosphate extraction, we determined the soluble SOM compounds (PY), and the organic matter in the extraction residue, considered as humins (HM). In a separate extraction (with 0.05 M H2SO4), low molecular weight (LMW) humus compounds were determined. The quantity of humic acids (HA) precipitated during Na-pyrophosphate extraction was determined as well. A spectroscopic method (UV-Vis) was used to characterize HA properties. The absorption coefficients E4/E6 were calculated based on the results of absorbance measurements involving 465- and 665-nm wavelengths of UV-Vis light. Statistical analyses were performed to find similarities and differences between soils differently used in Pruszków.

Results and discussion

The dominant part of the humus in the studied soils were humins HMs. There were two times more HM in the central part of the town than that in the peripheral zones. The same observation was made for soluble humus compounds (PY). The amount of LMW fractions was similar in soils of all uses. The degree of humification was small and averaged about 30% for all soils. Fulvic acid (FA) concentrations predominated over HA concentrations in all soils. The least condensed HA occurred in the allotment gardens with an E4/E6 ratio of 5.7, whereas the most condensed HAs were present in soil on arable lands (E4/E6 ratio of 4.7).

Conclusions

The studies have shown that the type of land use affects humus properties. The main differences were found to be in the quantity of humus compounds. Soils from the central part of the town contained more stable (HM) and soluble (PY) compounds than soils in the outskirts of town. PY compounds were characterized by a simple structure. Fulvic acids (FA) dominated in all of the studied soils (low HA/FA ratio). A high E4/E6 ratio indicates low maturity of humic fractions with low molecular weight compounds.
Resilience in high‐risk adolescents of mothers with recurrent depressive disorder: The contribution of fathers
Authors: Mahedy Liam , Harold Gordon T. , Maughan Barbara , Gardner Frances , Araya Ricardo , Bevan Jones Rhys , Hammerton Gemma , Sellers Ruth , Thapar Anita , Collishaw Stephan
Published: April 2018

This study examines the role of paternal emotional support as a resilience promoter in offspring of mothers with depression by considering the role of fathers' mental health and the quality of the couple relationship. Two hundred and sixty‐five mothers with recurrent unipolar depression, partners and adolescents from Wales were assessed. Paternal emotional support, couple relationship quality, and paternal depression were assessed at baseline; adolescent mental health symptoms were assessed using the Child and Adolescent Psychiatric Assessment at follow‐up. Results showed evidence of an indirect pathway whereby couple relationship quality predicted paternal emotional support (β = −.21, 95% CI [−.34, −.08]; p = .002) which in turn predicted adolescent depression (β = −.18, 95% CI [−.33, −.04]; p = .02), but not disruptive behaviours (β = −.08, 95% CI [−.22, .07]; p = .30), after controlling for relevant confounders. The findings highlight that fathers and the broader family system play an important role in enhancing resilience to depression symptoms in at‐risk adolescents.
Doublecortin expression in CD8+ T‐cells and microglia at sites of amyloid‐β plaques: A potential role in shaping plaque pathology?
Authors: Unger Michael S. , Marschallinger Julia , Kaindl Julia , Klein Barbara , Johnson Mary , Khundakar Ahmad A. , Roßner Steffen , Heneka Michael T. , Couillard‐Despres Sebastien , Rockenstein Edward , Masliah Eliezer , Attems Johannes , Aigner Ludwig
Published: April 2018

Introduction

One characteristic of Alzheimer's disease is the formation of amyloid‐β plaques, which are typically linked to neuroinflammation and surrounded by inflammatory cells such as microglia and infiltrating immune cells.

Methods

Here, we describe nonneurogenic doublecortin (DCX) positive cells, DCX being generally used as a marker for young immature neurons, at sites of amyloid‐β plaques in various transgenic amyloid mouse models and in human brains with plaque pathology.

Results

The plaque‐associated DCX+ cells were not of neurogenic identity, instead most of them showed coexpression with markers for microglia (ionized calcium‐binding adapter molecule 1) and for phagocytosis (CD68 and TREM2). Another subpopulation of plaque‐associated DCX+ cells was negative for ionized calcium‐binding adapter molecule 1 but was highly positive for the pan‐leukocyte marker CD45. These hematopoietic cells were identified as CD3‐and CD8‐positive and CD4‐negative T‐cells.

Discussion

Peculiarly, the DCX+/ionized calcium‐binding adapter molecule 1+ microglia and DCX+/CD8+ T‐cells were closely attached, suggesting that these two cell types are tightly interacting and that this interaction might shape plaque pathology.
The Colletotrichum dracaenophilum, C. magnum and C. orchidearum species complexes
Authors: Damm U. , Sato T. , Alizadeh A. , Groenewald J.Z. , Crous P.W.
Published: April 2018

Although Glomerella glycines, Colletotrichum magnum and C. orchidearum are known as causal agents of anthracnose of soybean, Cucurbitaceae and Orchidaceae, respectively, their taxonomy remains unresolved. In preliminary analyses based on ITS,
strains of these species appear basal in Colletotrichum phylogenies, clustering close to C. cliviae, C. brevisporum and other recently described species from tropical or subtropical regions. Phylogenetic analyses (ITS, GAPDH, CHS-1, HIS3, ACT, TUB2)
of 102 strains previously identified as Ga. glycines, C. magnum and C. orchidearum as well as other related strains from different culture collections and studies placed these taxa in three species complexes, and distinguished at least 24 species, including 11
new species. In this study, C. magnum, C. orchidearum and C. piperis were epitypified and their taxonomy resolved, while C. cliviicola was proposed as a new name for C. cliviae. Furthermore, a sexual morph was observed for C. yunnanense,
while C. brevisporum, C. cliviicola and C. tropicicola were reported from new hosts or countries. Regarding their conidial morphology, species in the C. dracaenophilum, C. magnum and C. orchidearum species complexes are reminiscent
of C. gloeosporioides or C. boninense s. lat., and were likely to be confused with them in the past.
“Text It” program to track falls in patients with Alzheimer's disease and dementia
Authors: Kamil Rebecca J. , Bakar Dara , Ehrenburg Matthew , Frankenthaler Scott , Wei Eric X. , Anson Eric , Oh Esther , Agrawal Yuri
Published: April 2018

Introduction

Falls are a significant problem among older adults with Alzheimer's disease, leading to high rates of fracture, hospitalization, and death. Tracking falls in older adults, particularly those with cognitive impairment, is a clinical and research challenge.

Methods

This prospective pilot study evaluated the feasibility of a text message program to track falls among patients with dementia. We also compared this technique with the calendar method of fall data collection.

Results

There was a 96% completion rate of text messaging and 100% of calendars; however, the text‐gathered data were more accurate.

Discussion

A text‐messaging platform to track falls shows promise in cognitively impaired individuals.
Sign of the Dust Impact‐Antenna Coupling Cloud
Authors: Kellogg Paul J. , Goetz Keith , Monson Steven J.
Published: April 2018

Data from dust impacts on the STEREO antennas themselves are used to show that the emitted ionized cloud is positively charged and therefore contains mainly ions.
The Rainfall Responses of Typhoon Soudelor (2015) to Radiative Processes of Cloud Species
Authors: Wang Bin , Xu Huiyan , Zhai Guoqing , Li Xiaofan
Published: April 2018

In this study, the three‐dimensional Weather Research and Forecasting model is used to conduct sensitivity experiments of Typhoon Soudelor in 2015 to examine rainfall responses to radiative effects of cloud species. Time and model domain mean analysis shows that the radiative effects of cloud ice and snow on rainfall are significantly stronger than those of cloud water and raindrops. The peak of snow appears in the upper troposphere (9 km). The inclusion of radiative effects of snow enhances radiative cooling in the upper troposphere and suppresses radiative cooling in midtroposphere and lower troposphere. The enhanced radiative cooling in the upper troposphere and the suppressed in midmidtroposphere and lower troposphere reduce stability in the troposphere and thus enhance vertical mass divergence and associated divergence of heat flux. The increases in net condensation and rainfall correspond to the increase in release of latent heat associated with the enhancement in divergence of heat flux. The maximum of cloud ice occurs around the tropopause (11 km). The inclusion of radiative effects of cloud ice weakens radiative cooling in the upper troposphere, while it enhances radiative cooling in the lower stratosphere. The weakened radiative cooling in the upper troposphere increases stability in the troposphere and thus reduces vertical mass divergence and associated divergence of heat flux. The reductions in net condensation and rainfall correspond to the decrease in release of latent heat associated with the suppression in divergence of heat flux.
An Analysis of Current and Electric Field Pulses Associated With Upward Negative Lightning Flashes Initiated from the Säntis Tower
Authors: He Lixia , Azadifar Mohammad , Rachidi Farhad , Rubinstein Marcos , Rakov Vladimir A. , Cooray Vernon , Pavanello Davide , Xing Hongyan
Published: April 2018

We present a study on the characteristics of current and electric field pulses associated with upward lightning flashes initiated from the instrumented Säntis Tower in Switzerland. The electric field was measured 15 km from the tower. Upward flashes always begin with the initial stage composed of the upward‐leader phase and the initial‐continuous‐current (ICC) phase. Four types of current pulses are identified and analyzed in the paper: (1) return‐stroke pulses, which occur after the extinction of the ICC and are preceded by essentially no‐current time intervals; (2) mixed‐mode ICC pulses, defined as fast pulses superimposed on the ICC, which have characteristics very similar to those of return strokes and are believed to be associated with the reactivation of a decayed branch or the connection of a newly created channel to the ICC‐carrying channel at relatively small junction heights; (3) “classical” M‐component pulses superimposed on the continuing current following some return strokes; and (4) M‐component‐type ICC pulses, presumably associated with the reactivation of a decayed branch or the connection of a newly created channel to the ICC‐carrying channel at relatively large junction heights. We consider a data set consisting of 9 return‐stroke pulses, 70 mixed‐mode ICC pulses, 11 classical M‐component pulses, and 19 M‐component‐type ICC pulses (a total of 109 pulses). The salient characteristics of the current and field waveforms are analyzed. A new criterion is proposed to distinguish between mixed‐mode and M‐component‐type pulses, which is based on the current waveform features. The characteristics of M‐component‐type pulses during the initial stage are found to be similar to those of classical M‐component pulses occurring during the continuing current after some return strokes. It is also found that about 41% of mixed‐mode ICC pulses were preceded by microsecond‐scale pulses occurring in electric field records some hundreds of microseconds prior to the onset of the current, very similar to microsecond‐scale electric field pulses observed for M‐component‐type ICC pulses and which can be attributed to the junction of an in‐cloud leader channel to the current‐carrying channel to ground. Classical M‐component pulses and M‐component‐type ICC pulses tend to have larger risetimes ranging from 6.3 to 430 μs. On the other hand, return‐stroke pulses and mixed‐mode ICC pulses have current risetimes ranging from 0.5 to 28 μs. Finally, our data suggest that the 8‐μs criterion for the current risetime proposed by Flache et al. is a reasonable tool to distinguish between return strokes and classical M‐components. However, mixed‐mode ICC pulses superimposed on the ICC can sometimes have considerably longer risetimes, up to about 28 μs, as observed in this study.
Peroxy mediated Csp2–Csp3 dehydrogenative coupling: regioselective functionalization of coumarins and coumarin-3-carboxylic acids
Authors: Jafarpour Farnaz , Darvishmolla Masoumeh
Published: April 2018

Regioselective functionalization of coumarins/coumarin carboxylic acids at C-3 via activation of Csp3–H bonds of ethers under metal-free conditions is developed.
The amplified electrochemiluminescence response signal promoted by the Ir(iii)-containing polymer complex
Authors: Fang Yayun , Wang Ziyu , Li Yang , Quan Yiwu , Cheng Yixiang
Published: April 2018

A novel Ir(iii)-containing polymer complex can emit an apparently enhanced ECL signal using TPrA as a co-reactant in CH3CN solution due to the effective intramolecular metal–ligand charge transfer (MLCT) from the Ir(iii)-complex centre to the polymer backbone.
PVBA-UiO-66 using a flexible PVBA with multi-coordination groups as mixed ligands and their super adsorption towards methylene blue
Authors: Yang Yongfang , Niu Zhanghao , Li Hua , Ma Yehui , Zhang Yue , Wang Hefang
Published: April 2018

A series of poly-vinyl benzoic acid (PVBA) and UiO-66 materials (PVBA-UiO-66) were prepared by a mixed-linker approach.
One-dimensional controllable crosslinked polymers grafted with N-methyl-d-glucamine for effective boron adsorption
Authors: Kang Jingjing , Tang Yakun , Gao Shasha , Liu Lang
Published: April 2018

Modified one-dimensional crosslinked polymers exhibit good adsorption performances for boron, and magnetic separation is realized by doping Fe3O4 nanoparticles.
A new redox-based and stepwise synthetic strategy lead to an unprecedented mixed-valence Keggin-type tungstovanadophosphate (WVI/VIV) bi-capped by vanadium(VIII)-complexes
Authors: Chen Wu-Hua , Lai Yu-Zhen , Hu Zhi-Biao , Liu Jin-Xian , Guo Xiang-Guang , Yuan Qiu-Lan , Zhao Jin-Hua , Mi Jin-Xiao , Luo Jiang-Shui
Published: April 2018

A new POM-based VIII-organic coordination compound has been prepared using a redox-based and stepwise synthetic strategy.
Luminescent metal–organic frameworks as chemical sensors: common pitfalls and proposed best practices
Authors: Diamantis Stavros A. , Margariti Antigoni , Pournara Anastasia D. , Papaefstathiou Giannis S. , Manos Manolis J. , Lazarides Theodore
Published: April 2018

In this review we approach the emerging field of sensors based on luminescent metal–organic frameworks from the perspective of the most commonly encountered pitfalls and we suggest best practices so that they can be avoided.
Enhancing light hydrocarbon storage and separation through introducing Lewis basic nitrogen sites within a carboxylate-decorated copper–organic framework
Authors: Liu Xiuping , Fan Weidong , Zhang Minghui , Li Guixia , Liu Haijun , Sun Daofeng , Zhao Lianming , Zhu Houyu , Guo Wenyue
Published: April 2018

A novel copper–organic framework (NEM-4) with functional groups exhibits both outstanding C1–C3 hydrocarbon uptakes and selectivities under ambient conditions.
Enantioselective indium(i)-catalyzed [4 + 2] annulation of alkoxyallenes and β,γ-unsaturated α-keto esters
Authors: Li Sujia , Lv Jian , Luo Sanzhong
Published: April 2018

An indium(i)–chiral phosphoric acid complex was found to catalyze the enantioselective [4 + 2] annulation reaction of β,γ-unsaturated α-keto esters with alkoxyallenes, affording cyclic O,O-acetals in good yields and with high regio- and stereo-selectivities.
Significant enhancement of the performance of hydrogen evolution reaction through shape-controlled synthesis of hierarchical dendrite-like platinum
Authors: Lin Liu , Sun Zemin , Yuan Mengwei , He Jinlu , Long Run , Li Huifeng , Nan Caiyun , Sun Genban , Ma Shulan
Published: April 2018

Hierarchically structured Pt micro-pine dendrites were prepared via a one-step solvothermal method, which exhibited excellent catalytic activity and significantly enhanced stability in comparison with the commercial Pt/C.
The chemistry of disks around T Tauri and Herbig Ae/Be stars
Authors: Agúndez Marcelino , Roueff Evelyne , Le Petit Franck , Le Bourlot Jacques
Published: April 2018

Context.Infrared and (sub-)millimeter observations of disks around T Tauri and Herbig Ae/Be stars point to a chemical differentiation, with a lower detection rate of molecules in disks around hotter stars.

Aims.We aim to investigate the underlying causes of the chemical differentiation indicated by observations and perform a comparative study of the chemistry of T Tauri and Herbig Ae/Be disks. This is one of the first studies to compare the chemistry in the outer regions of these two types of disk.

Methods.We developed a model to compute the chemical composition of a generic protoplanetary disk, with particular attention to the photochemistry, and applied it to a T Tauri and a Herbig Ae/Be disk. We compiled cross sections and computed photodissociation and photoionization rates at each location in the disk by solving the far-ultraviolet (FUV) radiative transfer in a 1+1D approach using the Meudon PDR code and adopting observed stellar spectra.

Results.The warmer disk temperatures and higher ultraviolet flux of Herbig stars compared to T Tauri stars induce some differences in the disk chemistry. In the hot inner regions, H2O, and simple organic molecules like C2H2, HCN, and CH4are predicted to be very abundant in T Tauri disks and even more in Herbig Ae/Be disks, in contrast with infrared observations that find a much lower detection rate of water and simple organics toward disks around hotter stars. In the outer regions, the model indicates that the molecules typically observed in disks, like HCN, CN, C2H, H2CO, CS, SO, and HCO+, do not have drastic abundance differences between T Tauri and Herbig Ae disks. Some species produced under the action of photochemistry, like C2H and CN, are predicted to have slightly lower abundances around Herbig Ae stars due to a narrowing of the photochemically active layer. Observations indeed suggest that these radicals are somewhat less abundant in Herbig Ae disks, although in any case, the inferred abundance differences are small, of a factor of a few at most. A clear chemical differentiation between both types of disks concerns ices. Owing to the warmer temperatures of Herbig Ae disks, one expects snow lines lying farther away from the star and a lower mass of ices compared to T Tauri disks.

Conclusions.The global chemical behavior of T Tauri and Herbig Ae/Be disks is quite similar. The main differences are driven by the warmer temperatures of the latter, which result in a larger reservoir or water and simple organics in the inner regions and a lower mass of ices in the outer disk.
Resolving faint structures in the debris disk around TWA 7
Authors: Olofsson J. , van Holstein R. G. , Boccaletti A. , Janson M. , Thébault P. , Gratton R. , Lazzoni C. , Kral Q. , Bayo A. , Canovas H. , Caceres C. , Ginski C. , Pinte C. , Asensio-Torres R. , Chauvin G. , Desidera S. , Henning Th. , Langlois M. , Milli J. , Schlieder J. E. , Schreiber M. R. , Augereau J.-C. , Bonnefoy M. , Buenzli E. , Brandner W. , Durkan S. , Engler N. , Feldt M. , Godoy N. , Grady C. , Hagelberg J. , Lagrange A.-M. , Lannier J. , Ligi R. , Maire A.-L. , Mawet D. , Ménard F. , Mesa D. , Mouillet D. , Peretti S. , Perrot C. , Salter G. , Schmidt T. , Sissa E. , Thalmann C. , Vigan A. , Abe L. , Feautrier P. , Le Mignant D. , Moulin T. , Pavlov A. , Rabou P. , Rousset G. , Roux A.
Published: April 2018

Context. Debris disks are the intrinsic by-products of the star and planet formation processes. Most likely due to instrumental limitations and their natural faintness, little is known about debris disks around low mass stars, especially when it comes to spatially resolved observations.

Aims. We present new VLT/SPHERE IRDIS dual-polarization imaging (DPI) observations in which we detect the dust ring around the M2 spectral type star TWA 7. Combined with additional angular differential imaging observations we aim at a fine characterization of the debris disk and setting constraints on the presence of low-mass planets.

Methods. We modeled the SPHERE DPI observations and constrain the location of the small dust grains, as well as the spectral energy distribution of the debris disk, using the results inferred from the observations, and performed simple N-body simulations.

Results. We find that the dust density distribution peaks at ~0.72′′ (25 au), with a very shallow outer power-law slope, and that the disk has an inclination of ~13° with a position angle of ~91° east of north. We also report low signal-to-noise ratio detections of an outer belt at a distance of ~1.5′′ (~52 au) from the star, of a spiral arm in the southern side of the star, and of a possible dusty clump at 0.11′′. These findings seem to persist over timescales of at least a year. Using the intensity images, we do not detect any planets in the close vicinity of the star, but the sensitivity reaches Jovian planet mass upper limits. We find that the SED is best reproduced with an inner disk at ~0.2′′ (~7 au) and another belt at 0.72′′ (25 au).

Conclusions. We report the detections of several unexpected features in the disk around TWA 7. A yet undetected 100M⊕ planet with a semi-major axis at 20−30 au could possibly explain the outer belt as well as the spiral arm. We conclude that stellar winds are unlikely to be responsible for the spiral arm.
L’informel et le non-marchand dans les systèmes d’activités : enquête représentative sur les ménages kanak en tribus de Nouvelle-Calédonie
Authors: Apithy Leïla , Guyard Stéphane , Bouard Séverine , Passouant Michel , Sourisseau Jean-Michel , Bélières Jean-François
Published: April 2018

Afin d’appréhender le rôle essentiel du travail de la terre et des activités de prélèvement (pêche et chasse) dans l’économie des tribus en Nouvelle-Calédonie, une enquête représentative de l’ensemble du pays, jusqu’à un niveau de 10 unités territoriales au sein des 3 provinces, a été réalisée en 2011 sur les activités de l’année 2010. Une partie des données de cette enquête est accessible au lien suivant :https://dataverse.cirad.fr(DOI :10.18167/DVN1/VWWVXU). Afin de permettre leur réutilisation, le présent article détaille le cadre conceptuel de l’enquête, la description du jeu de données, ainsi qu’une appréciation de sa qualité.