bluuebunny/crossref_metadata_2025 huggingface dataset:
GABAergic and cholinergic modulation of repetition suppression in inferior temporal cortex
Authors: Kuravi Pradeep , Vogels Rufin
Published: August 2018

Neurons in many brain areas of different species reduce their response when a stimulus is repeated. Such adaptation or repetition suppression is prevalent in inferior temporal (IT) cortex. The mechanisms underlying repetition suppression in IT are still poorly understood. Studies in rodents and in-vitro experiments suggest that acetylcholine and GABA can contribute to repetition suppression by interacting with fatigue-related or local adaptation mechanisms. Here, we examined the contribution of cholinergic and GABAergic mechanisms to repetition suppression in macaque IT, using an adaptation paradigm in which familiar images were presented successively with a short interstimulus interval. We found that intracortical local injections of acetylcholine and of the GABAA receptor antagonist Gabazine both increased repetition suppression in awake macaque IT. The increased repetition suppression was observed for both spiking activity and local field potential power. The latter was present mainly for frequencies below 50 Hz, spectral bands that typically do not show consistent repetition suppression in IT. Although increased with drug application, repetition suppression remained stimulus selective. These findings agree with the hypothesis that repetition suppression of IT neurons mainly results from suppressed input from upstream and other IT neurons but depend less on intrinsic neuronal fatigue.
Promising post-consumer PET-derived activated carbon electrode material for non-enzymatic electrochemical determination of carbofuran hydrolysate
Authors: Ayyalusamy Sureshkumar , Mishra Susmita , Suryanarayanan Vembu
Published: August 2018

In this work, activated carbon (AC) materials, prepared from polyethylene terephthalate (PET) waste bottles were used as the sensing platform for the indirect detection of carbofuran. The morphology and surface properties of the PET-derived AC (PET-AC) were characterized by N2 adsorption/desorption isotherm, X-ray diffraction (XRD), field-emission scanning/transmission electron microscopy (FE-SEM/TEM) and Raman spectroscopy. The electrochemical activity of the PET-AC modified glassy carbon electrode (GCE) (PET-AC/GCE) was measured by cyclic voltammetry and amperometry. The enhanced surface area and desirable porosities of PET-AC are attributed for the superior electrocatalytic activity on the detection of carbofuran phenol, where, the proposed sensor shows low detection limit (0.03 µM) and remarkable sensitivity (0.11 µA µM−1 cm−2). The PET-AC/GCE holds high selectivity towards potentially interfering species. It also provides desirable stability, repeatability and reproducibility on detection of carbofuran phenol. Furthermore, the proposed sensor is utilized for the detection of carbofuran phenol in real sample applications. The above mentioned unique properties and desirable electrochemical performances suggest that the PET-derived AC is the most suitable carbonaceous materials for cost-effective and non-enzymatic electrochemical sensor.
Large conformational changes of a highly dynamic pre-protein binding domain in SecA
Authors: Ernst Isabel , Haase Maximilian , Ernst Stefan , Yuan Shuguang , Kuhn Andreas , Leptihn Sebastian
Published: August 2018

SecA is an essential molecular motor for the translocation of proteins across the membrane via the bacterial Sec secretion system. While the Sec system is found in all cells from archaea to multicellular eukaryotes, the SecA protein is mainly found in bacteria. The mechanism of how the motor protein works on a molecular level is still under dispute but it is well established that SecA binds ATP and uses its hydrolysis for the translocation of substrates. In this work, we addressed the question of which conformational changes the protein might undergo during protein translocation. To this end, we investigated the molecular movements of SecA in the absence or the presence of ATP using single-molecule FRET measurements and in silico normal mode analyses. Our results demonstrate that the pre-protein binding domain of SecA is highly dynamic in the absence of the nucleotide and moves towards the helical wing domain in an ATP-bound state.
Direct quantification of nanoparticle surface hydrophobicity
Authors: Valsesia Andrea , Desmet Cloé , Ojea-Jiménez Isaac , Oddo Arianna , Capomaccio Robin , Rossi François , Colpo Pascal
Published: August 2018

Hydrophobicity is an important parameter for the risk assessment of chemicals, but standardised quantitative methods for the determination of hydrophobicity cannot be applied to nanomaterials. Here we describe a method for the direct quantification of the surface energy and hydrophobicity of nanomaterials. The quantification is obtained by comparing the nanomaterial binding affinity to two or more engineered collectors, i.e. surfaces with tuned hydrophobicity. In order to validate the concept, the method is applied to a set of nanoparticles with varying degrees of hydrophobicity. The technique described represents an alternative to the use of other methods such as hydrophobic interaction chromatography or water–octanol partition, which provide only qualitative values of hydrophobicity.
The first annotated set of scanning electron microscopy images for nanoscience
Authors: Aversa Rossella , Modarres Mohammad Hadi , Cozzini Stefano , Ciancio Regina , Chiusole Alberto
Published: August 2018

In this paper, we present the first publicly available human-annotated dataset of images obtained by the Scanning Electron Microscopy (SEM). A total of roughly 22,000 SEM images at the nanoscale are classified into 10 categories to form 4 labeled training sets, suited for image recognition tasks. The selected categories span the range of 0D objects such as particles, 1D nanowires and fibres, 2D films and coated surfaces as well as patterned surfaces, and 3D structures such as microelectromechanical system (MEMS) devices and pillars. Additional categories such as tips and biological are also included to expand the spectrum of possible images. A preliminary degree of hierarchy is introduced, by creating a subtree structure for the categories and populating them with the available images, wherever possible.
Computational workflow to study the seasonal variation of secondary metabolites in nine different bryophytes
Authors: Peters Kristian , Gorzolka Karin , Bruelheide Helge , Neumann Steffen
Published: August 2018

In Eco-Metabolomics interactions are studied of non-model organisms in their natural environment and relations are made between biochemistry and ecological function. Current challenges when processing such metabolomics data involve complex experiment designs which are often carried out in large field campaigns involving multiple study factors, peak detection parameter settings, the high variation of metabolite profiles and the analysis of non-model species with scarcely characterised metabolomes. Here, we present a dataset generated from 108 samples of nine bryophyte species obtained in four seasons using an untargeted liquid chromatography coupled with mass spectrometry acquisition method (LC/MS). Using this dataset we address the current challenges when processing Eco-Metabolomics data. Here, we also present a reproducible and reusable computational workflow implemented in Galaxy focusing on standard formats, data import, technical validation, feature detection, diversity analysis and multivariate statistics. We expect that the representative dataset and the reusable processing pipeline will facilitate future studies in the research field of Eco-Metabolomics.
An acquisition, curation and management workflow for sustainable, terabyte-scale marine image analysis
Authors: Schoening Timm , Köser Kevin , Greinert Jens
Published: August 2018

Optical imaging is a common technique in ocean research. Diving robots, towed cameras, drop-cameras and TV-guided sampling gear: all produce image data of the underwater environment. Technological advances like 4K cameras, autonomous robots, high-capacity batteries and LED lighting now allow systematic optical monitoring at large spatial scale and shorter time but with increased data volume and velocity. Volume and velocity are further increased by growing fleets and emerging swarms of autonomous vehicles creating big data sets in parallel. This generates a need for automated data processing to harvest maximum information. Systematic data analysis benefits from calibrated, geo-referenced data with clear metadata description, particularly for machine vision and machine learning. Hence, the expensive data acquisition must be documented, data should be curated as soon as possible, backed up and made publicly available. Here, we present a workflow towards sustainable marine image analysis. We describe guidelines for data acquisition, curation and management and apply it to the use case of a multi-terabyte deep-sea data set acquired by an autonomous underwater vehicle.
Overview of Click Polymerization
Authors: Huang Die , Qin AnJun , Tang Ben Zhong
Published: August 2018

Click polymerizations with remarkable advantages have been nurtured into powerful polymerization techniques with widespread applications. In this overview, several types of click polymerizations and their applications are briefly summarized. Of these, azide–alkyne click polymerizations (AACPs) are the most widely used due to the easy availability of the monomers and the stability of the products. AACPs catalyzed by Cu(i) and Ru(ii) can offer 1,4- and 1,5-regioregular PTAs, respectively. Meanwhile, 1,4-regioregular PTAs can also be obtained via metal-free click polymerizations of activated alkynes and azides or activated azides and alkynes. 1,5-regioregular PTAs can be produced by organic base-mediated AACP. Thiol-ene click polymerizations are versatile tools for the preparation of polythioethers with linear and hyperbranched structures. Similarly, thiol-yne click polymerizations, as the updated version of the former, can provide polythioethers and poly (vinyl sulfide)s (PVSs) with diverse structures. Novel reversible polymers can be yielded via Diels–Alder click polymerizations. Some new click polymerizations have also been researched for the synthesis of functional polymers with various structures. With these efficient polymerization techniques in hand, polymer scientists have prepared a large number of polymers with unique properties, such as luminescence, photonic patterning, adjustable light refractivity, optical nonlinearity, biodegradability, catalyst activity, self-assembly and self-healing.
Metal-free Azide–Alkyne Click Polymerization
Authors: Li Baixue , Qin Anjun , Tang Ben Zhong
Published: August 2018

Cu(i)-catalyzed azide–alkyne click polymerization has been widely applied in diverse areas. However, the removal of metal residues from the products is not a trivial task. To completely surmount this difficulty, the metal-free click polymerization (MFCP) of azides and alkynes is highly demanded. In this chapter, the recent developments of alkyne–azide MFCP are summarized, and the properties and applications of the resultant polytriazoles are introduced. Meanwhile, the opportunities and challenges in this area are also briefly discussed.
Catalyst-free Click Polymerization Using Nitrile N-Oxides Applicable to Various Dipolarophiles
Authors: Takata T. , Koyama Y. , Sogawa H.
Published: August 2018

This chapter provides an overview of the recent progress regarding click polymerizations using nitrile N-oxides applicable to various dipolarophiles. The pronounced reactivity of nitrile N-oxides enables metal (or catalyst)-free 1,3-dipolar cycloadditions with unsaturated bond-containing compounds such as alkynes, alkenes, and nitriles, indicating high potential in the synthesis of a variety of macromolecules and supramolecules via “click” molecular integration. For this purpose, kinetically stabilized nitrile N-oxides play a particularly important role. The first part of this chapter deals with the general topics of nitrile N-oxides, i.e. chemistry, synthetic methods, and reactions. The main discussion is divided into two parts: one is devoted to aromatic nitrile N-oxides, and the other is on aliphatic nitrile N-oxides, because these nitrile N-oxides have somewhat different features in terms of synthesis and reactivity. One of the most attractive features of nitrile N-oxides is that they undergo efficient cycloaddition under solvent-free conditions. Considering these features, it is obvious that nitrile N-oxides have very high potential to open a new world of click reactions and polymerizations. The number of publications mainly on polymerization using nitrile N-oxides is cited at the end of this chapter.
Thiol-yne Click Polymerization
Authors: Zheng Yaochen , Gao Chao
Published: August 2018

Thiol-yne click polymerization (TYCP) is one of the most significant synthetic techniques for artificial polymers, due to its simplicity, efficiency, and functionality tolerance. In nature, it is a classic nucleophilic addition reaction and a step-growth polymerization, which can be initiated or accelerated in the presence of free-radicals, amines, and transition metals, respectively. Its rate is greatly influenced by the structures (i.e., their electrophilicity and steric hindrance) of the used thiols and/or alkynes. With aliphatic monomers being used as feeding materials, the topological architectures (such as linear, branching, and cross-linked network, etc.) and available functional groups (such as hydroxyl, carboxyl, amino, and epoxy groups, and so on) can be facilely tailored via altering the chemical structure and feeding order. In contrast, for aromatic monomers, mono-addition occurs only during the process of thiol-yne click reaction, leading exclusively to linear poly(vinyl thioether)s. These sulfur-containing polymers synthesized by TYCP are promising to be widely utilized as high refractive index materials, photovoltaic materials, drug-delivery vehicles, biomaterials, and hybrid materials, etc.
Thiol-epoxy and Amine-epoxy ‘Click’ Polymerizations
Authors: Stuparu Mihaiela C. , Khan Anzar
Published: August 2018

Although an old reaction, the interest in the thiol-epoxy reaction, especially as a polymerization process, is only recent. The power of this chemistry lies in its efficiency and operation under ambient conditions, the commercial availability of a vast variety of thiol- and epoxide-carrying molecules that can be utilized as monomers, the long list of polymerization catalysts and associated solvent systems, and the formation of a hydroxyl group upon completion. The amine-epoxy reaction bears similar hallmarks, but is relatively simpler as a catalyst is not required for this process. Moreover, in comparison with the thiol-epoxy system, which may sometimes give rise to disulfide defects through oxidative dimerization of thiols, the amine-epoxy system is comparatively more robust and insensitive to such a side reaction. The polymers resulting from thiol-epoxy and amine-epoxy reactions are termed as poly(β-hydroxythio-ether)s and poly(β-hydroxyl amine)s, respectively. The polymerization process itself is referred to as ‘proton transfer polymerization’. This is because quenching of the alkoxide anion, generated upon the nucleophilic attack of the thiolate or amine moiety on the epoxide unit, through protonation, is the critical step that ultimately decides the nature of propagation and the final structure of the polymer. It is understood that multiple proton donors can exist within a polymerization system. Our attempt here is to document the growing interest in the aforementioned chemistries as a polymerization process. Since the backbones are reactive, we will also detail post-polymerization modification approaches of these polymers. Last but not least, an overview is given and the future directions are identified.
Multicomponent Polymerization Mediated by Click Chemistry
Authors: Tian Wen , Hu Rongrong , Tang Ben Zhong
Published: August 2018

Multicomponent polymerizations (MCPs) have received widespread attention and are becoming a powerful tool for the synthesis of polymers. The Cu(ɪ)-catalyzed MCPs are a vibrant branch of multicomponent polymerizations, which inherit the various advantages of multicomponent reactions (MCRs) and click reactions. This chapter will focus on the development of Cu(ɪ)-catalyzed MCRs in polymer synthesis. Click reaction-mediated multicomponent polymerization has been applied for the synthesis of a library of linear, hyperbranched, core–shell-type, graft and dendronized polymers with high molecular weights and high yields, which show great potential for the construction of functional polymer materials.
Porphyrinoid biohybrid materials as an emerging toolbox for biomedical light management
Authors: Almeida-Marrero Verónica , van de Winckel Eveline , Anaya-Plaza Eduardo , Torres Tomás , de la Escosura Andrés
Published: August 2018

The present article reviews the most important developing strategies in light-induced nanomedicine, based on the combination of porphyrinoid photosensitizers with a wide variety of biomolecules and biomolecular assemblies.
Using hyperpolarised NMR and DFT to rationalise the unexpected hydrogenation of quinazoline to 3,4-dihydroquinazoline
Authors: Richards Josh E. , Hooper Alexander J. J. , Bayfield Oliver W. , Cockett Martin C. R. , Dear Gordon J. , Holmes A. Jonathon , John Richard O. , Mewis Ryan E. , Pridmore Natalie , Roberts Andy D. , Whitwood Adrian C. , Duckett Simon B.
Published: August 2018

Hyperpolarised NMR allows the tracking of the DFT-rationalised outer sphere hydrogenation of quinazoline.
MOF/polymer composite synthesized using a double solvent method offers enhanced water and CO2 adsorption properties
Authors: Peng Li , Yang Shuliang , Sun Daniel T. , Asgari Mehrdad , Queen Wendy L.
Published: August 2018

A double solvent method is for the first time used to synthesize polymer composites showing enhanced water and CO2 adsorption properties.
A tetravalent sialic acid-coated tetraphenylethene luminogen with aggregation-induced emission characteristics: design, synthesis and application for sialidase activity assay, high-throughput screening of sialidase inhibitors and diagnosis of bacterial vaginosis
Authors: Liu Guang-jian , Wang Beihan , Zhang Yuan , Xing Guo-wen , Yang Xiaoli , Wang Shu
Published: August 2018

A sialic acid-coated tetraphenylethene luminogen with excellent hydrophilicity was reported for sialidase activity assay and diagnosis of bacterial vaginosis.
Structure of a Cd(ii) mixed-ligand coordination polymer: single crystalline conductance switch involving photoinduced electron transfer and photocoloration
Authors: Huang Jia , Zhang Jie , He Runhua , Fu Zhiyong
Published: August 2018

A novel Cd(ii)-MOF with tunable photophysical behavior has been developed. The control of color, fluorescence emission and conductivity is achieved in a single crystalline conductance switch by incorporating donor and acceptor building blocks into a molecular wire.
Solution-processed resistive switching memory devices based on hybrid organic–inorganic materials and composites
Authors: Shan Yingying , Lyu Zhensheng , Guan Xinwei , Younis Adnan , Yuan Guoliang , Wang Junling , Li Sean , Wu Tom
Published: August 2018

We review emerging low-cost solution-processed resistive random-access memory (ReRAM) made of either hybrid nanocomposites or hybrid organo-lead halide perovskites.
Structure–property analysis of julolidine-based nonlinear optical chromophores for the optimization of microscopic and macroscopic nonlinearity
Authors: Wu Jieyun , Wang Wen , Wang Nan , He Juan , Deng Guowei , Li Zhonghui , Zhang Xiaoling , Xiao Hongyan , Chen Kaixin
Published: August 2018

A structure–property relation investigation revealed that the theoretical hyperpolarizability and experimental solvatochromism were more reliable in julolidine-based nonlinear optical chromophore design.
Ground-state molecular and electronic structures of group-IV nanoribbons, nanorings and nanotubes
Authors: Matsunaga YouKey , Takeda Kyozaburo
Published: August 2018

Based on ab initio molecular orbital (MO) theory and first-principles band calculations, we systematically study the ground-state molecular and electronic structures of group-IV nanoribbons (NRBs), nanorings (NRGs) and nanotubes (NTBs) by substituting the honeycomb skeletal atoms with C, Si or Ge atoms.
Integrated, multi-process approach to total nutrient recovery from stored urine
Authors: Jagtap Neha , Boyer Treavor H.
Published: August 2018

This research investigated an integrated, multi-process approach of struvite precipitation, ammonia stripping–acid absorption, and evaporation to recover NPK from stored urine.
Efficient ionic liquid-based platform for multi-enzymatic conversion of carbon dioxide to methanol
Authors: Zhang Zhibo , Muschiol Jan , Huang Yuhong , Sigurdardóttir Sigyn Björk , von Solms Nicolas , Daugaard Anders E. , Wei Jiang , Luo Jianquan , Xu Bao-Hua , Zhang Suojiang , Pinelo Manuel
Published: August 2018

Low yields commonly obtained during enzymatic conversion of CO2 to methanol are attributed to low CO2 solubility in water.
Gaining insight into the photophysical properties of a coumarin STP ester with potential for bioconjugation
Authors: González-Pérez M. , Ooi S. Y. , Martins S. , Prates Ramalho João P. , Pereira A. , Caldeira A. T.
Published: August 2018

The photophysical properties of a coumarin 392 4-sulfotetrafluorophenyl ester, C392STP (sodium (E/Z)-4-(4-(2-(6,7-dimethoxycoumarin-3-yl)vinyl)-benzoyl)-2,3,5,6-tetrafluoro-benzenesulfonate), an amine reactive coumarine with potential for bioconjungation, have been studied in different solvents.
A bis-naphthalimide functionalized pillar[5]arene-based supramolecular π-gel acts as a multi-stimuli-responsive material
Authors: Zhang You-Ming , Li Yong-Fu , Zhong Kai-Peng , Qu Wen-Juan , Yao Hong , Wei Tai-Bao , Lin Qi
Published: August 2018

A novel approach for the design of multi-stimuli-responsive supramolecular functional materials was successfully developed by introducing the competition of π–π stacking and cation–π interactions into a pillar[5]arene-based supramolecular π-gel (MP5-G).
Ratiometric fluorescence, solution-phase and filter-paper visualization detection of ciprofloxacin based on dual-emitting carbon dot/silicon dot hybrids
Authors: Gui Rijun , Bu Xiangning , He Weijie , Jin Hui
Published: August 2018

This study demonstrates the ratiometric fluorescence, solution-phase and filter-paper visual detection of ciprofloxacin based on dual-emitting carbon dot/silicon dot hybrids.
A fast and powerful swimming microrobot with a serrated tail enhanced propulsion interface
Authors: Li Dengfeng , Liu Yanting , Yang Yuanyuan , Shen Yajing
Published: August 2018

A serrated tail with multiple channels and nanointerfaces is used for the first time in a 3D swimming microrobot to enhance chemical reaction interfaces and realize powerful high-speed motion.
Root-growth of boron nitride nanotubes: experiments and ab initio simulations
Authors: Santra Biswajit , Ko Hsin-Yu , Yeh Yao-Wen , Martelli Fausto , Kaganovich Igor , Raitses Yevgeny , Car Roberto
Published: August 2018

Arc-plasma synthesis and ab initio simulations find a growth mechanism of boron nitride nanotubes.
Enhanced visible-light photocatalytic degradation by Mn3O4/CeO2 heterojunction: a Z-scheme system photocatalyst
Authors: Ma Yongjin , Jiang Jing , Zhu Anquan , Tan Pengfei , Bian Yuan , Zeng Weixuan , Cui Hao , Pan Jun
Published: August 2018

A novel 1-D Mn3O4/CeO2 heterojunction exhibited enhanced photocatalytic degradation via a Z-scheme system.
DABCO-catalyzed Knoevenagel condensation of aldehydes with ethyl cyanoacetate using hydroxy ionic liquid as a promoter
Authors: Meng Dan , Qiao Yongsheng , Wang Xin , Wen Wei , Zhao Sanhu
Published: August 2018

N-(2-Hydroxy-ethyl)-pyridinium chloride ([HyEtPy]Cl) was synthesized and explored as a novel promoter for 1,4-diazabicyclo [2.2.2] octane (DABCO)-catalyzed Knoevenagel condensation reactions, excellent catalytic activity was obtained.
Construction of graphene oxide based mixed matrix membranes with CO2-philic sieving gas-transport channels through strong π–π interactions
Authors: Cong Shenzhen , Li Hui , Shen Xiangjian , Wang Jing , Zhu Junyong , Liu Jindun , Zhang Yatao , Van der Bruggen Bart
Published: August 2018

Two-dimensional nanomaterials can be used to create innovative membranes with high permeability and selectivity, but precise manipulation of laminar stacking and the construction of ordered, CO2-philic molecular sieving channels remains a technological challenge.
A smart nano-V2O5/ODA-coated mesh for a co-responsive photo-induced wettability transition and ROS generation for in situ water purification
Authors: Qu Ruixiang , Zhang Weifeng , Li Xiangyu , Liu Yanan , Shih Tzungyu , Wei Yen , Feng Lin
Published: August 2018

A smart nano-V2O5/ODA-coated mesh with co-responsive photo-induced wettability transition and ROS generation was fabricated.
Mammalian DNA methyltransferases: new discoveries and open questions
Authors: Gowher Humaira , Jeltsch Albert
Published: August 2018

As part of the epigenetic network, DNA methylation is a major regulator of chromatin structure and function. In mammals, it mainly occurs at palindromic CpG sites, but asymmetric methylation at non-CpG sites is also observed. Three enzymes are involved in the generation and maintenance of DNA methylation patterns. DNMT1 has high preference for hemimethylated CpG sites, and DNMT3A and DNMT3B equally methylate unmethylated and hemimethylated DNA, and also introduce non-CpG methylation. Here, we review recent observations and novel insights into the structure and function of mammalian DNMTs (DNA methyltransferases), including new structures of DNMT1 and DNMT3A, data on their mechanism, regulation by post-translational modifications and on the function of DNMTs in cells. In addition, we present news findings regarding the allosteric regulation and targeting of DNMTs by chromatin modifications and chromatin proteins. In combination, the recent publications summarized here impressively illustrate the intensity of ongoing research in this field. They provide a deeper understanding of key mechanistic properties of DNMTs, but they also document still unsolved issues, which need to be addressed in future research.
The role of mTOR-mediated signals during haemopoiesis and lineage commitment
Authors: Malik Natasha , Sansom Owen J. , Michie Alison M.
Published: August 2018

The serine/threonine protein kinase mechanistic target of rapamycin (mTOR) has been implicated in the regulation of an array of cellular functions including protein and lipid synthesis, proliferation, cell size and survival. Here, we describe the role of mTOR during haemopoiesis within the context of mTORC1 and mTORC2, the distinct complexes in which it functions. The use of conditional transgenic mouse models specifically targeting individual mTOR signalling components, together with selective inhibitors, have generated a significant body of research emphasising the critical roles played by mTOR, and individual mTOR complexes, in haemopoietic lineage commitment and development. This review will describe the profound role of mTOR in embryogenesis and haemopoiesis, underscoring the importance of mTORC1 at the early stages of haemopoietic cell development, through modulation of stem cell potentiation and self-renewal, and erythroid and B cell lineage commitment. Furthermore, the relatively discrete role of mTORC2 in haemopoiesis will be explored during T cell development and B cell maturation. Collectively, this review aims to highlight the functional diversity of mTOR signalling and underline the importance of this pathway in haemopoiesis.
The molecular clock and evolutionary timescales
Authors: Luo Arong , Ho Simon Y. W.
Published: August 2018

The molecular clock provides a valuable means of estimating evolutionary timescales from genetic and biochemical data. Proposed in the early 1960s, it was first applied to amino acid sequences and immunological measures of genetic distances between species. The molecular clock has undergone considerable development over the years, and it retains profound relevance in the genomic era. In this mini-review, we describe the history of the molecular clock, its impact on evolutionary theory, the challenges brought by evidence of evolutionary rate variation among species, and the statistical models that have been developed to account for these heterogeneous rates of genetic change. We explain how the molecular clock can be used to infer rates and timescales of evolution, and we list some of the key findings that have been obtained when molecular clocks have been applied to genomic data. Despite the numerous challenges that it has faced over the decades, the molecular clock continues to offer the most effective method of resolving the details of the evolutionary timescale of the Tree of Life.
Denoising, deconvolving, and decomposing multi-domain photon observations
Authors: Pumpe Daniel , Reinecke Martin , Enßlin Torsten A.
Published: August 2018

Astronomical imaging based on photon count data is a non-trivial task. In this context we show how to denoise, deconvolve, and decompose multi-domain photon observations. The primary objective is to incorporate accurate and well motivated likelihood and prior models in order to give reliable estimates about morphologically different but superimposed photon flux components present in the data set. Thereby we denoise and deconvolve photon counts, while simultaneously decomposing them into diffuse, point-like and uninteresting background radiation fluxes. The decomposition is based on a probabilistic hierarchical Bayesian parameter model within the framework of information field theory (IFT). In contrast to its predecessor D3PO, D4PO reconstructs multi-domain components. Thereby each component is defined over its own direct product of multiple independent domains, for example location and energy. D4PO has the capability to reconstruct correlation structures over each of the sub-domains of a component separately. Thereby the inferred correlations implicitly define the morphologically different source components, except for the spatial correlations of the point-like flux. Point-like source fluxes are spatially uncorrelated by definition. The capabilities of the algorithm are demonstrated by means of a synthetic, but realistic, mock data set, providing spectral and spatial information about each detected photon. D4PO successfully denoised, deconvolved, and decomposed a photon count image into diffuse, point-like and background flux, each being functions of location as well as energy. Moreover, uncertainty estimates of the reconstructed fields as well as of their correlation structure are provided employing their posterior density function and accounting for the manifolds the domains reside on.
Interplanetary dust delivery of water to the atmospheres of Pluto and Triton
Authors: Poppe A. R. , Horányi M.
Published: August 2018

Context. Both Pluto and Triton possess thin, N2-dominated atmospheres controlled by sublimation of surface ices.

Aims. We aim to constrain the influx and ablation of interplanetary dust grains into the atmospheres of both Pluto and Triton in order to estimate the rate at which oxygen-bearing species are introduced into both atmospheres.

Methods. We use (i) an interplanetary dust dynamics model to calculate the flux and velocity distributions of interplanetary dust grains relevant for both Pluto and Triton and (ii) a model for the ablation of interplanetary dust grains in the atmospheres of both Pluto and Triton. We sum the individual ablation profiles over the incoming mass and velocity distributions of interplanetary dust grains in order to determine the vertical structure and net deposition of water to both atmospheres.

Results. Our results show that <2% of silicate grains ablate at either Pluto or Triton while approximately 75% and >99% of water ice grains ablate at Pluto and Triton, respectively. From ice grains, we calculate net water influxes to Pluto and Triton of ~3.8 kg day−1 (8.5 × 103 H2O cm−2 s−1) and ~370 kg day−1 (6.2 × 105 H2O cm−2 s−1), respectively. The significant difference in total water deposition between Pluto and Triton is due to the presence of Triton within Neptune’s gravity well, which both enhances interplanetary dust particle (IDP) fluxes due to gravitational focusing and accelerates grains before entry into Triton’s atmosphere, thereby causing more efficient ablation.

Conclusions. We conclude that water deposition from dust ablation plays only a minor role at Pluto due to its relatively low flux. At Triton, water deposition from IDPs is more significant and may play a role in the alteration of atmospheric and ionospheric chemistry. We also suggest that meteoric smoke and smaller, unablated grains may serve as condensation nuclei for the formation of hazes at both worlds.
A posteriori error estimation for Magnus-type integrators
Authors: Auzinger Winfried , Hofstätter Harald , Koch Othmar , Quell Michael , Thalhammer Mechthild
Published: August 2018

We study high-order Magnus-type exponential integrators for large systems of ordinary differential equations defined by a time-dependent skew-Hermitian matrix. We construct and analyze defect-based local error estimators as the basis for adaptive stepsize selection. The resulting procedures provide a posteriori information on the local error and hence enable the accurate, efficient, and reliable time integration of the model equations. The theoretical results are illustrated on two numerical examples .
D-Dimer and TAT Measurement in Patients with Deep Venous Thrombosis: Utility in Diagnosis and Judgement of Anticoagulant Treatment Effectiveness
Authors: Speiser Wolfgang , Mallek Reinhold , Koppensteiner Renate , Andreas Stümpflen , Kapiotis Stylianos , Minar Erich , Ehringer Herbert , Lechner Klaus
Published: August 2018

The plasma levels of thrombin-antithrombin III-complexes (TAT) and the fibrin split product D-Dimer were measured in 39 patients with phlebographically proven acute DVT: 34 patients had proximal DVT, 5 had calf DVT The sensitivity of D-Dimer and TAT measurements in the diagnosis of proximal DVT was found to be dependent on the duration of symptoms: 0 to 7 days (n = 27): elevated D-Dimer levels (>120 ng/ml) = 1, D-Dimer Latex test positive (>500 ng/ml) = 1, elevated TAT levels (>6 ng/ml) = 0.88. Eight to 14 days (n = 7): elevated D-Dimer levels = 1, D-Dimer Latex test positive = 0.33, elevated TAT levels = 0.66; specificity: elevated D-Dimer: 0.48, D-Dimer Latex test: 1, elevated TAT: 0.76. Calf DVT patients (n = 5) had elevated D-Dimer levels, negative Latex tests and 3 of them had normal TAT values. Hemostatic and fibrinolytic parameters were also determined in 13 patients during heparin treatment of proximal DVT. Elevated D-Dimer and TAT levels rapidly decreased after initiation of anticoagulant therapy. In 2 of 13 patients a marked increase in D-Dimer and TAT levels was observed in periods of ineffective heparinization, documented by normal or only slightly prolonged thrombin clotting times. We conclude from our results that 1) D-Dimer El A measurement, in contrast to TAT measurement, shows a very high sensitivity in the diagnosis of DVT, 2) due to low specificity this test can only be used to exclude thrombosis in patients with suspected DVT, and 3) the determination of the plasma levels of D-Dimer and TAT may be useful for judging the effect of anticoagulant treatment on thrombotic processes.
The Effects of Long-Term Using Once-A-Month Injectable Contraceptive Norethisterone Enanthate/ Estradiol Valerate on Coagulation in the Chinese
Authors: Meng Yuan-Xiang , Jiang Hai-Ying , Lu Feng-Ying
Published: August 2018

Sixty-four Chinese women were studied for the effects of injecting once-a-month contraceptive norethisterone enanthate/ estradiol valerate between 2 to 4 1/2 years on certain coagulation and fibrinolytic parameters, and 59 women not receiving any steroidal contraception were controls. In both groups there was no significant change in PT, fibrinogen, factor X activity, AT III antigen, AT III activity and fibrinolytic activity expressed by euglobulin lysis time. There was no significant difference in mean levels of factor VIIIR:Ag between the two groups, although a sub-group women in treatment group had higher than accepted levels of factor VIIIR:Ag.
Stress Induced Release of Plasminogen Activator from Lysosomes
Authors: Beard E. L , Busuttil R. W , Gottshalk S. K
Published: August 2018

Mild hemorrhage was found to bring about a slight increase in the plasminogen activator activity of the blood serum of albino rats. This change coincided with a minor increase in the plasminogen activator activity of the liver microsomes of these rats and a significant increase in that of the liver lysosomes. Presumably the stress was sufficient to increase lysosomal permeability allowing for a greater outflow of plasminogen activator into the body fluids.

Drum trauma and acid phosphatase injections brought about a similar release of plasminogen activator and acid phosphatase which intensified when the two were applied together. Rats which had previously been made resistant to drum trauma responded only slightly to either stress alone but their resistance was overcome when both stresses were applied together.
Plasmatic and Thrombocytic Anti-Plasmins and Anti-Activators II.
Authors: den Ottolander G. J. H , Leijnse B , Cremer-Elfrink H. M. J
Published: August 2018

Values for inhibitors in plasma and in platelets against plasmin and against different activators were measured in normal test persons. The influence of freezing and thawing, of heating to 60° C and of destruction in other ways was assessed. The reaction pattern of all these inhibitors was established. It appears that there are differences in behaviour amongst these inhibitors. In patients with a high and with a low anti-UK there was no correlation with the levels of inhibitors directed against blood activator, obtained in several ways, SK and tissue activator.

The conclusion is that anti-UK is not representative for anti-activator activity in general. There are indications that blood activator liberated with different stimuli is one substance.
Plasmatic and Platelet Anti-Plasmins and Anti-Activators
Authors: den Ottolander G. J. H , Leijnse B , Cremer-Elfrink M. J. H
Published: August 2018

The values for plasmatic and thrombocytic anti-plasmin and anti-UK were determined in normal test persons and in 107 patients with different diseases.

In 12 patients with a fresh venous thrombosis the values of these inhibitors were within normal limits.

In 6 patients with liver cirrhosis no significantly lowered values were found.

Also in patients with different haematological diseases no abnormality was found. A relationship between plasmatic and thrombocytic anti-UK was found.
Fibrinolysis and Alimentary Lipaemia in Whites and Bantus; Their Relationship and Response to Intravenous Heparin
Authors: Lackner H , Sougin-Mibashan R
Published: August 2018

Summary and Conclusion

1. Diurnal variation in fibrinolysis is marked in the Whites and almost absent in the Bantu. >

2. The difference in fibrinolytic activity beween White and Bantu has been confirmed, but was found to decrease over the course of the morning due to diurnal variation in the White subjects.

3. The ingestion of butter fat does not inhibit fibrinolysis to any appreciable extent in either White or Bantu.

4. The accelerating effect of heparin on fibrinolysis was found to be present in lipaemic plasma, but appears to be distinct from the fat-clearing effect.
Convenient New Bedside and Laboratory Method for the Control of Anticoagulant Therapy
Authors: Hartert H
Published: August 2018

A new simple method is described for the determination of thromboplastin time on 0.02 ml of capillary blood. It employs an automatic pipette with a disposable mouthpiece (sections of a plastic capillary tube), which is replaced by a new one after each determination. The automatic pipette may be used in the same way for pipetting the thromboplastin suspension into the test tube. The latter is the only utensil, which has to be cleaned after the determination.

In comparison with other procedures of thromboplastin time determinations, the new micro-method has been found as reliable as “macro”-methods using venous blood.
6-oxo-Prostaglandin F1α and Thromboxane B2 in Uterine Vein Blood - A Possible Role in Menstrual Bleeding
Authors: Goodfellow C F , Paton R C , Salmon J A , Moncada S , Clayton J K , Davies J A , McNicol G P
Published: August 2018

The role of the haemostatic system in relation to menstrual bleeding is poorly understood. Platelet retention to glass beads and plasma concentrations of 6-oxo-PGFα and thromboxane B2 were measured in uterine and peripheral venous blood obtained from 18 women undergoing abdominal hysterectomy. Concentrations of 6-oxo-PGFα were significantly (p<0.01) higher in uterine (1.4 ± 0.3 ng/ml, mean ± SEM) than in peripheral vein blood (0.2 ±0.1 ng/ml) as was the level of thromboxane B2 (0.5 + 0.1 and 0.2 ± 0.1 ng/ml, respectively). Platelet retention in uterine vein blood (11 ± 4%) was significantly lower than in peripheral blood (42 ±4%; p<0.01) and the degree of platelet retention correlated inversely with the plasma concentration of 6-oxo-PGFα (r −0.43; p<0.01). There was a significant rank correlation between time since menstruation and concentrations of 6-oxo-PGFα in uterine (τ + 0.69; p<0.001) and peripheral (τ + 0.56; p<0.05) vein blood. The results indicate that an increased local production of prostacyclin (PGI2) relative to thromboxane A2 at the time of menstruation could contribute to the mechanism of uterine bleeding.
Protein C Level at Birth
Authors: Polack B , Pouzol P , Amiral J , Kolodie L
Published: August 2018

The protein C level was determined, on cord blood, for 30 healtly newborns by electro-immuno assay using a monospecific antiserum. For the newborns the mean level of protein C related antigen is about one third of normal adults’ mean level. There is a good correlation between Protein C related antigen and prothrombin related antigen. The low level of these vitamin-K-dependent proteins is probably a consequence of partial liver immaturity at birth. Using two-dimensional immuno-electrophoresis we were unable to detect subcarboxylated forms of protein C. However these abnormal forms could be seen in vitamin-K deficiencies of neonates.
Randomized Quality Improvement Trial of Opting-In Versus Opting-Out to Increase Influenza Vaccination Rates during Pregnancy
Authors: Wootton Susan , Blackwell Sean , Saade George , Berens Pamela , Hutchinson Maria , Green Charles , Sridhar Sujatha , Elam Kara , Tyson Jon
Published: August 2018

Introduction Despite strong recommendations, only 40.6% of pregnant women attending two prenatal clinics were vaccinated against influenza during the 2009 pandemic. We tested whether an opting-out approach would improve vaccine uptake.

Methods We conducted a randomized quality improvement (QI) trial to compare opting-out with conventional opting-in consent for influenza immunization. Women age ≥ 18 years attending the University of Texas Health Science Center at Houston (UTHealth) or UT-Medical Branch (UTMB) prenatal clinics during the 2010–2011 influenza season, were eligible.

Results We enrolled 280 women (140 UTHealth, 140 UTMB). Both groups had similar mean age (26.0 ± 5.5 years), mean gestational age (19.4 ± 9.5 weeks), and percent with underlying health conditions (20.7%). Vaccination rates with opting-in and opting-out were similar among all (83 vs. 84%), UTHealth (87 vs. 93%), and UTMB patients (79 vs.76%) (p > 0.05). In subsamples of patients assessed, consent strategy did not significantly affect maternal recall of information provided.

Conclusion While prenatal influenza vaccination uptake doubled from the 2009–2010 influenza season, opting-out did not perform better than opting-in, a conclusion opposite that we would have reached had this been a nonconcurrent trial. Vaccination rates dropped posttrial; hence, continued research is needed to increase the prenatal influenza immunizations.
Predictors of Hand Dexterity after Single-Digit Replantation
Authors: Kawamura Kenji , Omokawa Shohei , Shimizu Takamasa , Iida Akio , Tanaka Yasuhito , Nakanishi Akito
Published: August 2018

Background Microsurgical replantation of the thumb and digits has become an increasingly familiar technique in clinical practice worldwide. However, successful digit replantation does not always provide better hand function than revision amputation. Little information is available regarding predictors of motor skill activities of replanted hands. Therefore, we retrospectively evaluated hand dexterity after single-digit replantation at a minimum follow-up of 1 year and analyzed the factors influencing dexterity.

Methods This retrospective cohort study included 23 patients treated for amputation injuries at our institution from 2014 to 2015. Patients with amputations from Tamai's zone 2 to 5 of the thumb (3 patients), index finger (11 patients), or middle finger (9 patients) who underwent digital replantation surgery and were followed up for more than 1 year were included. Follow-up evaluations were conducted at an average of 23 months postoperatively (range: 13–25 months). We hypothesized that possible factors influencing hand dexterity after single-digit replantation were patient age, injured finger, key pinch strength, Semmes–Weinstein test result, and percentage of total active motion. Relationships between the outcome variable, which was the result of the Purdue Pegboard Test of hand dexterity, and explanatory variables were analyzed using Spearman's correlation coefficient. A p-value of < 0.05 indicated statistical significance.

Results No postoperative complications occurred. Univariate analysis indicated that decreased hand dexterity after single-digit replantation was significantly associated with older age (p = 0.001) and poor recovery of sensation, as shown by the Semmes–Weinstein test (p = 0.012).

Conclusion Patient age was a risk factor for low hand dexterity after replantation surgery. Recovery of finger sensitivity enhanced dexterity of motor skill activities following finger replantation surgery.
Temporal organization of magnetospheric fluctuations unveiled by recurrence patterns in the Dst index
Authors: Donner Reik V. , Stolbova Veronika , Balasis Georgios , Donges Jonathan F. , Georgiou Marina , Potirakis Stelios M. , Kurths Jürgen
Published: August 2018

Magnetic storms constitute the most remarkable large-scale phenomena of nonlinear magnetospheric dynamics. Studying the dynamical organization of macroscopic variability in terms of geomagnetic activity index data by means of complexity measures provides a promising approach for identifying the underlying processes and associated time scales. Here, we apply a suite of characteristics from recurrence quantification analysis (RQA) and recurrence network analysis (RNA) in order to unveil some key nonlinear features of the hourly Disturbance storm-time (Dst) index during periods with magnetic storms and such of normal variability. Our results demonstrate that recurrence-based measures can serve as excellent tracers for changes in the dynamical complexity along non-stationary records of geomagnetic activity. In particular, trapping time (characterizing the typical length of “laminar phases” in the observed dynamics) and recurrence network transitivity (associated with the number of the system’s effective dynamical degrees of freedom) allow for a very good discrimination between magnetic storm and quiescence phases. In general, some RQA and RNA characteristics distinguish between storm and non-storm times equally well or even better than other previously considered nonlinear characteristics like Hurst exponent or symbolic dynamics based entropy concepts. Our results point to future potentials of recurrence characteristics for unveiling temporal changes in the dynamical complexity of the magnetosphere.