bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermally driven homonuclear-stacking phase of MoS2through desulfurization
Authors: Hwang Young Hun , Yun Won Seok , Cha Gi-Beom , Hong Soon Cheol , Han Sang Wook
Published: April 2019

Homonuclear (AA) stacking derived from AA′ stacking of the hexagonal (2H) phase is retained even after further desulfurization of the remaining bottom S layer,i.e., full desulfurization of the top layer.
Fluorination-triggered tandem cyclization of styrene-type carboxylic acids to access 3-aryl isocoumarin derivatives under microwave irradiation
Authors: Yuan Jinwei , Zeng Fanlin , Mai Wenpeng , Yang Liangru , Xiao Yongmei , Mao Pu , Wei Donghui
Published: April 2019

A practical synthetic route through a fluorination-triggered tandem cyclization of styrene-type carboxylic acids was developed to construct a variety of 4-fluoro-3-aryl-3,4-dihydroisocoumarins and 3-arylisocoumarins.
Cu(0)-RDRP as an efficient and low-cost synthetic route to blue-emissive polymers for OLEDs
Authors: Tonge Christopher M. , Yuan Fanglong , Lu Zheng-Hong , Hudson Zachary M.
Published: April 2019

Cu(0)-RDRP has been used to prepare deep-blue emissive polymers for OLEDs using a simple room-temperature procedure with copper wire catalyst.
Self-amplified depolymerization of oligo(thiourethanes) for the release of COS/H2S
Authors: Powell Chadwick R. , Foster Jeffrey C. , Swilley Sarah N. , Kaur Kuljeet , Scannelli Samantha J. , Troya Diego , Matson John B.
Published: April 2019

Herein we report the self-amplified depolymerization of an aryl oligo(thiourethane) (OTU) for the release of COS/H2S.
Role of Al-doping with different sites upon the structure and electrochemical performance of spherical LiNi0.5Mn1.5O4 cathode materials for lithium-ion batteries
Authors: Chen Anyong , Kong Linglong , Shu Yang , Yan Wenchao , Wu Wei , Xu Yongji , Gao Hongtao , Jin Yongcheng
Published: April 2019

Al-doped spinel LiNi0.5Mn1.5O4 materials with different sites and contents were synthesized by rapid precipitation combined with hydrothermal treatment and calcination.
Fabrication of chemically stable hydrogen- and niobium-codoped ZnO transparent conductive films
Authors: Han Bing , Song Jianmin , Li Junjie , Guo Yajuan , Dai Binting , Meng Xudong , Song Weiye , Yang Fu , Wang Yanfeng
Published: April 2019

H- and Nb-doped ZnO (HNZO) thin films were fabricated on glass substrates with radio frequency magnetron sputtering.
Crystal-facet-dependent denitrosylation: modulation of NO release fromS-nitrosothiols by Cu2O polymorphs
Authors: Ghosh Sourav , Roy Punarbasu , Prasad Sanjay , Mugesh Govindasamy
Published: April 2019

Crystal facet-dependent Cu2O-mediated denitrosylation ofS-nitrosothiols and release of nitric oxide (NO) are described.
A hierarchical hybrid monolith: MoS42−-intercalated NiFe layered double hydroxide nanosheet arrays assembled on carbon foam for highly efficient heavy metal removal
Authors: Wang Yongchuang , Gu Yue , Xie Donghua , Qin Wenxiu , Zhang Haimin , Wang Guozhong , Zhang Yunxia , Zhao Huijun
Published: April 2019

A novel hierarchical hybrid monolith have been fabricated for highly efficient and selective heavy metal decontamination, accompanied by facile separation.
The structural origin of composition-driven magnetic transformation in BiFeO3-based multiferroics: a neutron diffraction study
Authors: Khomchenko V. A. , Karpinsky D. V. , Latushka S. I. , Franz A. , Sikolenko V. V. , Dubkov S. V. , Silibin M. V. , Paixão J. A.
Published: April 2019

The magnetic properties of BiFeO3-based multiferroics are determined by the competition between the polarization- and oxygen octahedra rotation-related components of the Dzyaloshinskii–Moriya interaction.
Climate change: essential knowledge for developing holistic solutions to our climate crisis
Authors: Maslin M. A.
Published: April 2019

Understanding anthropogenic climate change is essential for anyone working in the life sciences. Firstly because climate change has already started to impact the Earth biosphere and human health and these changes need to be documented and acknowledged. Secondly, many of the solutions to climate change, both mitigation and adaptation, will be through the life sciences, everything from massive reforestation and sustainable agriculture to preventing the spread of disease and protecting individual human health. Anthropogenic climate change is, therefore, one of the defining challenges of the 21st century, along with poverty alleviation, environmental degradation and global security. Climate change is no longer just a scientific concern but encompasses economics, sociology, geopolitics, national and local politics, law and health to name a few. Hence, to understand climate change fully then not only does one have to review the science but also the politics and geopolitics, which have created the issue and can provide the solutions. Climate change ultimately makes us examine the whole basis of modern society and ultimately asks questions about humanity's relationship with the rest of the planet.
Photometry, spectroscopy, and polarimetry of distant comet C/2014 A4 (SONEAR)
Authors: Ivanova Oleksandra , Luk’yanyk Igor , Kolokolova Ludmilla , Das Himadri Sekhar , Husárik Marek , Rosenbush Vera , Afanasiev Viktor , Svoreň Ján , Kiselev Nikolai , Krushinsky Vadim
Published: April 2019

Context.The study of distant comets, which are active at large heliocentric distances, is important for a better understanding of their physical properties and mechanisms of long-lasting activity.

Aims.We analyzed the dust environment of the distant comet C/2014 A4 (SONEAR), with a perihelion distance near 4.1 au, using comprehensive observations obtained by different methods.

Methods.We present an analysis of spectroscopy, photometry, and polarimetry of comet C/2014 A4 (SONEAR), which were performed on November 5–7, 2015, when its heliocentric distance was 4.2 au and phase angle was 4.7°. Long-slit spectra and photometric and linear polarimetric images were obtained using the focal reducer SCORPIO-2 attached to the prime focus of the 6 m telescope BTA (SAO RAS, Russia). We simulated the behavior of color and polarization in the coma presenting the cometary dust as a set of polydisperse polyshapes rough spheroids.

Results.No emission features were detected in the 3800–7200 Å wavelength range. The continuum showed a reddening effect with the normalized gradient of reflectivity 21.6 ± 0.2% per 1000 Å within the 4650–6200 Å wavelength region. The fan-like structure in the sunward hemisphere was detected. The radial profiles of surface brightness differ forr-sdss andg-sdss filters, indicating a predominance of submicron and micron-sized particles in the cometary coma. The dust color (g–r) varies from 0.75 ± 0.05mto 0.45 ± 0.06malong the tail. For an aperture radius near 20 000 km, the dust productions in various filters were estimated asAfρ= 680 ± 18 cm (r-sdss) and 887 ± 16 cm (g-sdss). The polarization map shows spatial variations in polarization over the coma from about −3% near the nucleus to −8% at a cometocentric distance of about 150 000 km. Our simulations show that the dust particles are dominated (or covered) by ice and tholin-like organics. Spatial changes in the color and polarization can be explained by particle fragmentation.
A non-homogeneous boundary value problem for the Kuramoto-Sivashinsky equation posed in a finite interval
Authors: Li Jing , Zhang Bing-Yu , Zhang Zhixiong
Published: April 2019

This paper studies the initial boundary value problem (IBVP) for the dispersive Kuramoto-Sivashinsky equation posed in a finite interval (0, L) with non-homogeneous boundary conditions. It is shown that the IBVP is globally well-posed in the space Hs(0, L) for any s > −2 with the initial data in Hs(0, L) and the boundary value data belonging to some appropriate spaces. In addition, the IBVP is demonstrated to be ill-posed in the space Hs(0, L) for any s < −2 in the sense that the corresponding solution map fails to be in C2.
Quercus ilex Extract Ameliorates Acute TNBS-Induced Colitis in Rats
Authors: Castejón Maria Luisa , Rosillo Maria Ángeles , Villegas Isabel , Sánchez-Hidalgo Marina , Hadidi Lila , Zaidi Farid , Alarcón-de-la-Lastra Catalina
Published: April 2019

Quercus ilex L. (Fagaceae) is one of the most commonly used plants in folk medicine in the Mediterranean region to treat gastrointestinal disorders. The aim of the present study was to evaluate the effects of a polyphenol extract from mature leaves of Q. ilex on acute 2,4,6-trinitrobenzene sulfonic acid-induced colitis in rats. A polyphenol extract from mature leaves of Q. ilex (250 and 500 mg/kg/day) was administered by gavage 48, 24, and 1 h prior to the induction of colitis with 2,4,6-trinitrobenzene sulfonic acid as well as 24 h later. The inflammation response was assessed by histology, myeloperoxidase activity, and Th1 proinflammatory cytokine production. The protein expression of cyclooxygenase-2 and inducible nitric oxide synthase, and signaling pathways were studied by Western blotting in the colon tissues. The polyphenol extract from mature leaves of Q. ilex decreased neutrophil infiltration, interleukin-1β and TNF-α production, and proinflammatory proteins cyclooxygenase-2 and inducible nitric oxide synthase overexpression. Also, the polyphenol extract from mature leaves of Q. ilex was capable of blocking the activation of mitogen-activated protein kinases and nuclear transcription factor-kappa B. Furthermore, the reduction of inflammation by polyphenol extract from mature leaves of Q. ilex treatment was accompanied by a recovery of Nrf2 and heme oxygenase-1 protein expression levels. In conclusion, this study demonstrates that a polyphenol extract from mature leaves of Q. ilex improves 2,4,6-trinitrobenzene sulfonic acid-induced colitis, probably through mitogen-activated protein kinase/nuclear transcription factor-kappa B inhibition and Nrf2/heme oxygenase-1 activation signaling pathways, thus reducing the production of Th1 proinflammatory cytokines and cyclooxygenase-2 and inducible nitric oxide synthase overexpression.
A New Wave of Amide Bond Formations for Peptide Synthesis
Authors: Hollanders Karlijn , Maes Bert , Ballet Steven
Published: April 2019

The construction of peptidic amide bonds has become a daily laboratory practice by virtue of well-established ‘coupling reagents’. Nonetheless, inherent limitations connected to these classical coupling methods in terms of waste, safety and expense have yet to be conquered. Research efforts have been devoted to synthetic methods able to surpass these limitations. This short review focuses on the advances made in these ‘non-classical’ methods for amide bond formation with a specific application in peptide chemistry. It consists of two main sections: (i) novel carboxylic activation reagents, and (ii) carboxylic acid and amine surrogates.

1 Introduction

2 Alternative Carboxylic acid Activation Reagents

3 Carboxylic Acid and Amine Surrogates

4 Conclusion and Perspectives
Case Report of an Infrequent Complication of Infective Endocarditis: The Complete Detachment from the Aorta of the Previous Vein Graft Anastomosis
Authors: Varela Barca Laura , López Menéndez Jose , Redondo Palacios Ana , Rodríguez-Roda Stuart Jorge
Published: April 2019

The authors report an unusual complication of acute infective endocarditis found in a 70-year-old man with a previous history of two cardiac surgery procedures. During median sternotomy, a massive bleeding occurred. The bleeding was contained within the mediastinum and originated from the 10-year-old anastomosis of the saphenous vein to a composite graft, which was completely detached due to infective endocarditis of the aortic graft.
Minimally Invasive Craniocervical Decompression for Chiari 1 Malformation: An Operative Technique
Authors: Quillo-Olvera Javier , Navarro-Ramírez Rodrigo , Quillo-Olvera Diego , Quillo-Reséndiz Javier , Kim Jin-Sung
Published: April 2019

Chiari malformation type 1 (CM-1) is an ectopia of the cerebellar tonsils below the foramen magnum that causes severe disability due to its neurologic symptoms. The treatment of choice for CM-1 is decompression of the craniovertebral junction (CVJ). In some patients only an extradural decompression by removing the atlanto-occipital ligament may be sufficient. In other patients, duraplasty is necessary. In this case, we report the operative technique used to treat a CM-1 in a 16-year-old male patient who presented with severe headache and gait instability. A micro-decompression of the suboccipital bone and posterior arch osteotomy of C1 through a 2-cm midline incision was performed under surgical microscope magnification. A duraplasty was performed through the same approach. The patient was discharged home after 2 days in the hospital and returned to regular activities at school 3 weeks after surgery. The minimally invasive technique presented here is a viable option for the posterior decompression of the CVJ in patients with CM-1 using a low-cost self-retaining retractor.
Using Artificial Intelligence to Identify Factors Associated with Autism Spectrum Disorder in Adolescents with Cerebral Palsy
Authors: Bertoncelli Carlo , Altamura Paola , Vieira Edgar , Bertoncelli Domenico , Solla Federico
Published: April 2019

Autism spectrum disorder (ASD) is common in adolescents with cerebral palsy (CP) and there is a lack of studies applying artificial intelligence to investigate this field and this population in particular. The aim of this study is to develop and test a predictive learning model to identify factors associated with ASD in adolescents with CP. This was a multicenter controlled cohort study of 102 adolescents with CP (61 males, 41 females; mean age ± SD [standard deviation] = 16.6 ± 1.2 years; range: 12–18 years). Data on etiology, diagnosis, spasticity, epilepsy, clinical history, communication abilities, behaviors, intellectual disability, motor skills, and eating and drinking abilities were collected between 2005 and 2015. Statistical analysis included Fisher's exact test and multiple logistic regressions to identify factors associated with ASD. A predictive learning model was implemented to identify factors associated with ASD. The guidelines of the “transparent reporting of a multivariable prediction model for individual prognosis or diagnosis” (TRIPOD) statement were followed. Type of spasticity (hemiplegia > diplegia > tri/quadriplegia; OR [odds ratio] = 1.76, SE [standard error] = 0.2785, p = 0.04), communication disorders (OR = 7.442, SE = 0.59, p < 0.001), intellectual disability (OR = 2.27, SE = 0.43, p = 0.05), feeding abilities (OR = 0.35, SE = 0.35, p = 0.002), and motor function (OR = 0.59, SE = 0.22, p = 0.01) were significantly associated with ASD. The best average prediction model score for accuracy, specificity, and sensitivity was 75%. Motor skills, feeding abilities, type of spasticity, intellectual disability, and communication disorders were associated with ASD. The prediction model was able to adequately identify adolescents at risk of ASD.
Measurement of P2 M-band flux asymmetry in indirect-drive hohlraum on Shenguang-III prototype laser facility
Authors: Li Qi , Guo Liang , Gong Tao , Li Zhichao , Yang Dong , Li Sanwei , Yang Jiamin
Published: April 2019

M-band flux asymmetry (MFA) may be another critical factor which can lead to low-mode distortion of implosion. We describe an experimental technique employing the x-ray fluorescence signature of material to investigate the MFA onto the capsule. Si was chosen to be the tracer layer since the inducing threshold for the K-shell fluorescence is much higher than soft x-ray but a little lower than M-band x-ray. The fluorescence images were recorded from a surrogate Si-coated ball, and thus, the P2 MFA was deduced from the fluorescence images.
Size distribution theory for jumping-droplet condensation
Authors: Zhang Lenan , Xu Zhenyuan , Lu Zhengmao , Du Jianyi , Wang Evelyn N.
Published: April 2019

Jumping-droplet condensation is promising for various applications where the droplet size distribution plays a key role in the overall system performance. Despite being extensively studied in recent works, inconsistencies existed in previous size distribution models as the droplet growth and removal mechanisms were often not properly described. Here, we developed a theoretical framework where the contact and the coalescence of droplets were identified as the dominant mechanisms for instantaneous size distribution change. We found a critical droplet diameter comparable to the average nucleation site distance, beyond which the droplet population decreased rapidly. This result is analogous to the well-known Fermi-Dirac distribution due to the underlying exclusive principle. We also showed the effect of the contact angle, that is, larger droplets become more probable as surface hydrophobicity increases. The coalescence count distribution given by the current theory agrees well with experimental data. Furthermore, we demonstrated the use of the proposed model in predicting condensation heat transfer coefficients, which also shows good agreement with previous experiments. Our size distribution theory elucidates the fundamental process of droplet growth and interactions leading to an overall size distribution during jumping-droplet condensation, which can be generally applied to self-cleaning, anti-icing/frosting, power generation, and water harvesting.
Community discovering in temporal network with spectral fusion
Authors: Huang Qiangjuan , Zhao Chengli , Zhang Xue , Yi Dongyun
Published: April 2019

With the deep understanding of the time-varying characteristics of real systems, research studies focusing on the temporal network spring up like mushrooms. Community detection is an accompanying and meaningful problem in the temporal network, but the analysis of this problem is still in its developing stage. In this paper, we proposed a temporal spectral clustering method to detect the invariable communities in the temporal network. Through integrating Fiedler’s eigenvectors of normalized Laplacian matrices within a limited time window, our method can avoid the inaccurate partition caused by the mutation of the temporal network. Experiments demonstrated that our model is effective in solving this problem and performs obviously better than the compared methods. The results illustrated that taking the historical information of the network structure into consideration is beneficial in clustering the temporal network.
Thermo-mechanical analysis of a probe for electron paramagnetic resonance spectroscopy operating at cryogenic temperatures
Authors: Dev Bodhayan , Gujjala Charan Raj , Maly Thorsten
Published: April 2019

In this article, we present the thermo-mechanical analysis of an electron paramagnetic resonance (EPR) probe operating at cryogenic temperatures using finite element analysis. Thermo-mechanical analysis plays a key role in the mechanical design evaluation process as EPR probes are often subjected to large stresses under such extreme conditions. For simplification, we assume thermal conduction to be the dominant mode of heat transfer over convection and radiation. The simulation model consists of a cryostat-probe assembly with appropriate thermal and structural boundary conditions. The predicted temperature distributions from the steady-state thermal analysis is then used for the stress analysis of the EPR probe. The stress analysis indicated that stresses in the EPR probe are below the ultimate strengths of each component, and thus safe for running EPR experiments. Furthermore, the simulation results were confirmed experimentally, and we found that the predicted heat losses for the EPR probe assembly and the sample holder are in excellent agreement with the experimental measurements.
Investigation of a submerging redox behavior in Fe2O3 solid electrolyte for resistive switching memory
Authors: Zhou Guangdong , Yang Xiude , Xiao Lihua , Sun Bai , Zhou Ankun
Published: April 2019

A redox reaction submerged by a high current magnitude is impressively observed in a Fe2O3 solid electrolyte-based resistive memory device at room temperature. Oxygen vacancy migration, Ag atom redox, phase-induced grain boundary, and water molecule interplay with the oxygen vacancy are responsible for the submerged redox behaviors. The observation of the submerged redox behavior in the Fe2O3 phase change process gives an insight into the evolution of memristors.
Singular cycles and chaos in a new class of 3D three-zone piecewise affine systems
Authors: Lu Kai , Yang Qigui , Chen Guanrong
Published: April 2019

It is a great challenge to detect singular cycles and chaos in dynamical systems with multiple discontinuous boundaries. This paper takes the challenge to investigate the coexistence of singular cycles, mainly homoclinic and heteroclinic cycles connecting saddle-focus equilibriums, in a new class of three-dimensional three-zone piecewise affine systems. It develops a method to accurately predict the coexisting homoclinic and heteroclinic cycles in such a system. Furthermore, this paper establishes some conditions for chaos to exist in the system, with rigorous mathematical proof of chaos emerged from the coexistence of these singular cycles. Finally, it presents numerical simulations to verify the theoretical results.
AlxTe1−x selector with high ovonic threshold switching performance for memory crossbar arrays
Authors: Gao Tian , Feng Jie , Ma Haili , Zhu Xi , Ma Zhixian
Published: April 2019

We report the fabrication of a bidirectional selector based on threshold switching (TS) material AlxTe1−x. By modulating the composition and the thickness of the AlxTe1−x film layer, an optimized bidirectional selector with the advantages of being electroforming-free, with sufficient operating current (1 mA), satisfactory selectivity (ca. 5.9 × 103), appropriately small threshold voltage (ca. ±0.7 V), and excellent switching uniformity was fabricated. The trap-limited conduction model was employed to explain the TS characteristics of the W/AlxTe1−x/W device. The application of a high electric field to the devices is considered to induce the tunneling of the high-electric field-derived carriers from deep traps to shallow traps, switching the device to the on-state.
InAlAs/InGaAs-MSM photodetectors based on optical cavity using metallic mirrors: THz frequency operation, high quantum efficiency and high saturation current
Authors: Billet Maximilien , Bretin Sara , Bavedila Fuanki , Avramovic Vanessa , Wallart Xavier , Coinon Christophe , Lampin Jean-François , Ducournau Guillaume , Peytavit Emilien
Published: April 2019

We present a metallic mirror-based resonant cavity-enhanced InAlAs/InGaAs metal-semiconductor-metal (InAlAs/InGaAs-MSM) photodetector driven by a 1550 nm wavelength illumination. The device shows a quantum efficiency higher than 30%, a cut-off frequency higher than 100 GHz, and a saturation current density above 40 kA/cm2. As a proof of concept, we demonstrate the generation of 0.25 mW of continuous wave output power at a frequency of 100 GHz via the photomixing of an optical beatnote. This result underlines the potential of InAlAs/InGaAs-MSM for subterahertz and terahertz optoelectronic applications driven by telecom lasers.
Rapid-throughput solution-based production of wafer-scale 2D MoS2
Authors: Robertson John , Blomdahl Daniel , Islam Kazi , Ismael Timothy , Woody Maxwell , Failla Jacqueline , Johnson Michael , Zhang Xiaodong , Escarra Matthew
Published: April 2019

Two-dimensional semiconductors, such as MoS2, are leading candidates for the production of next-generation optoelectronic devices such as ultrathin photodetectors and photovoltaics. However, the commercial application of 2D semiconductors is hindered by growth techniques requiring hours of heating and cooling cycles to produce large-area 2D materials. We present here a growth technique that leverages high-intensity optical irradiation of a solution-processed (NH4)2MoS4 precursor to synthesize MoS2 in one-tenth the time of typical furnace-based CVD. From start to finish, the technique produces uniform 2D MoS2 across 4-in. wafers within 15 min. Raman spectroscopy, in-plane XRD, and XPS show a 2H MoS2 crystal structure with a stoichiometry of 1.8:1 S:Mo. AFM scans show that the films are 2.0 nm thick MoS2 with a roughness of 0.68 nm. Photoluminescence spectroscopy reveals the characteristic 1.85 eV bandgap. The as-grown films were used to make field-effect transistors with a mobility of 0.022 cm2 V−1 s−1 and photodetectors with a responsivity of 300 mA/W and an external quantum efficiency of 0.016%, demonstrating their potential for optoelectronic device development. This rapid thermal processing growth technique reduces MoS2 synthesis time by an order of magnitude relative to comparable techniques and enables greater accessibility to 2D semiconductors for researchers and developers.
Low phase noise microwave frequency synthesizer for cold atom clock
Authors: Yu Mingyuan , Wang Yaning , Wan Jinyin , Wang Xin , Ouyang Xinchuan , Xiao Ling , Li Tang , Cheng Huadong , Liu Liang
Published: April 2019

We present a low phase noise microwave frequency synthesizer for the integrating sphere cold atom clock. The synthesizer is based on an ultralow-phase-noise oven-controlled crystal oscillator and employs a phase-locking technique. The absolute phase noise performance of the 6834 MHz signal was measured to be −60 and −120 dBc/Hz at offset frequencies of 1 Hz and 10 kHz, respectively. For the new scheme, the direct digital synthesizer is used to tune the clock output. The frequency tuning resolution was improved to 3.4 × 10−15. This scheme for the microwave frequency synthesizer can also be used in other precision measurements.
Angular momentum compensation manipulation to room temperature of the ferrimagnet Ho3−xDyxFe5O12 detected by the Barnett effect
Authors: Imai Masaki , Chudo Hiroyuki , Ono Masao , Harii Kazuya , Matsuo Mamoru , Ohnuma Yuichi , Maekawa Sadamichi , Saitoh Eiji
Published: April 2019

We demonstrate that the angular momentum compensation temperature TA, at which the net angular momentum in the sample disappears, can be controlled in Ho3Fe5O12 by partially substituting Dy for Ho. TA can be detected using the Barnett effect, by which mechanical rotation magnetizes an object due to spin-rotation coupling. We found that TA increases with the Dy content and clarified that TA of Ho1.5Dy1.5Fe5O12 coincides with room temperature. The Barnett effect enables us to explore materials applicable to magnetic devices utilizing the angular momentum compensation only by rotating the powder sample at room temperature.
Sex-specific structural and functional leaf traits and sun–shade acclimation in the dioecious tree Pistacia vera (Anacardiaceae)
Authors: Korgiopoulou C. , Bresta P. , Nikolopoulos D. , Karabourniotis G.
Published: April 2019

In dioecious species, sex-related adaptive strategies, influenced by natural and sexual selection, allow each sex to meet the specific demands of reproduction. Differences in ecophysiological traits between males and females may rely on innate differences in secondary sex traits such as structural and functional leaf traits. We tested structural sexual leaf dimorphism in Pistacia vera L. and the intersexual differences in sun–shade acclimation processes expected from the different adaptive strategies of males and females. Fifteen structural and functional leaf traits were compared in 50-year-old trees between females with low fruit load and males under sun and shade conditions. Despite the low additional energy investment in reproduction in females, remarkable sex effects in leaf structure and function were observed. Male trees had smaller leaves with significantly lower total conducting petiole area (TCA) and higher stomatal density, water use efficiency and concentration of phenolic compounds; females had larger leaves with greater thickness, leaf mass per area, TCA and maximum photosynthetic capacity per area (Amax,a). The higher Amax,a and stomatal conductance of female leaves were associated with their ~20-fold higher TCA compared with male trees. Females seem to invest more in high xylem efficiency and rates of C gain; males invest more in defence-protection. Sun–shade plastic responses were sex- and trait-specific, but the plasticity assessment indicated that both sexes have evolved an almost equal degree of phenotypic plasticity that allows them to perform optimally under varying environmental conditions. However, the trait-specific differences indicate that each sex displays a different strategy of optimisation.
Emergence of topological electronic phases in elemental lithium under pressure
Authors: Mack Stephanie A. , Griffin Sinéad M. , Neaton Jeffrey B.
Published: April 2019

Significance

Lithium forms the lightest metallic phase under standard conditions and undergoes an unusual sequence of phase transitions to lower symmetry structures under pressure. We use density functional theory to study the electronic structure of several predicted high-pressure phases of lithium. At 80 GPa, we find its electronic structure becomes topologically nontrivial, with the electrons behaving as massless fermions. Lithium is unique in that it is a light elemental solid where the topological features of the band structure are well isolated from other bands at the Fermi level. Our results indicate that the electronic structure of lithium has previously unexplored topological properties with pressure, adding another dimension to an already remarkable complex phase diagram for an elemental solid.
Parameters and the design of the Language Faculty
Authors: Manzini Maria Rita
Published: April 2019

FollowingBerwick and Chomsky (2011), parameters are degrees of freedom open at the externalization (EXT) of syntactico-semantic structures (SEM) by sensorimotor systems (PHON) (Section 1). Within this framework, inSection 2I focus on a case study concerning Northern Italian subject clitics, also raising the well-known question how to reconcile observable microvariation with the desideratum of a reduced number of (macro)parameters.Sections 3reviews recent relevant models of parameterization, the Rethinking Comparative Syntax model (ReCoS,Biberauer et al. 2014) and the Parameters & Schemata model (Longobardi 2005,2017).Sections 4–5return to the case study, taking the reductionist view that parameters may be just categorial cuts, such as the 1/2P vs 3P split, interacting with externalization and other general principles of grammar.
Mining novel biosynthetic machineries of secondary metabolites from actinobacteria
Authors: Katsuyama Yohei
Published: April 2019

Secondary metabolites produced by actinobacteria have diverse structures and important biological activities, making them a useful source of drug development. Diversity of the secondary metabolites indicates that the actinobacteria exploit various chemical reactions to construct a structural diversity. Thus, studying the biosynthetic machinery of these metabolites should result in discovery of various enzymes catalyzing interesting and useful reactions. This review summarizes our recent studies on the biosynthesis of secondary metabolites from actinobacteria, including the biosynthesis of nonproteinogenic amino acids used as building blocks of nonribosomal peptides, the type II polyketide synthase catalyzing polyene scaffold, the nitrous acid biosynthetic pathway involved in secondary metabolite biosynthesis and unique cytochrome P450 catalyzing nitrene transfer. These findings expand the knowledge of secondary metabolite biosynthesis machinery and provide useful tools for future bioengineering.
Biomass and nitrogen distribution ratios reveal a reduced root investment in temperate lianas vs. self-supporting plants
Authors: Wyka Tomasz P , Zadworny Marcin , Mucha Joanna , Żytkowiak Roma , Nowak Kinga , Oleksyn Jacek
Published: April 2019

Background and Aims

The reliance on external support by lianas has been hypothesized to imply a reduction in the biomass cost of stem construction and root anchorage, and an increased investment in leaves, relative to self-supporting plants. These evolutionary trade-offs have not been adequately tested in an ontogenetic context and on the whole-plant scale. Moreover, the hypothesis may be extended to other potentially limiting resources, such as nitrogen (N.)

Methods

Plants belonging to five con-familiar pairs of temperate liana/shrub species were cultivated in 120 L barrels and sequentially harvested over up to three growing seasons. To account for the ontogenetic drift, organ biomass and nitrogen fractions were adjusted for plant biomass and N pool, respectively.

Key Results

Lianas invested, on average, relatively less biomass in the root fraction in comparison with shrubs. This was offset by only insignificant increases in leaf or stem investment. Even though liana stems and roots showed higher N concentration in comparison with shrubs, plant N distribution was mostly driven by, and largely matched, the pattern of biomass distribution. Lianas also showed a greater relative growth rate than shrubs. The differences between the growth forms became apparent only when ontogenetic drift was controlled for. These results were confirmed regardless of whether reproductive biomass was included in the analysis.

Conclusions

Our results suggest that temperate lianas, in spite of their diverse, species-specific resource distribution patterns, preferentially allocate resources to above-ground organs at the expense of roots. By identifying this trade-off and demonstrating the lack of a general trend for reduction in stem investment in lianas, we significantly modify the prevailing view of liana allocation strategies and evolutionary advantages. Such a resource distribution pattern, along with the cheap unit leaf area and stem unit length construction, situates lianas as a group close to the fast acquisition/rapid growth end of the life strategy spectrum.
RAxML-NG: a fast, scalable and user-friendly tool for maximum likelihood phylogenetic inference
Authors: Kozlov Alexey M , Darriba Diego , Flouri Tomáš , Morel Benoit , Stamatakis Alexandros
Published: April 2019

Motivation

Phylogenies are important for fundamental biological research, but also have numerous applications in biotechnology, agriculture and medicine. Finding the optimal tree under the popular maximum likelihood (ML) criterion is known to be NP-hard. Thus, highly optimized and scalable codes are needed to analyze constantly growing empirical datasets.

Results

We present RAxML-NG, a from-scratch re-implementation of the established greedy tree search algorithm of RAxML/ExaML. RAxML-NG offers improved accuracy, flexibility, speed, scalability, and usability compared with RAxML/ExaML. On taxon-rich datasets, RAxML-NG typically finds higher-scoring trees than IQTree, an increasingly popular recent tool for ML-based phylogenetic inference (although IQ-Tree shows better stability). Finally, RAxML-NG introduces several new features, such as the detection of terraces in tree space and the recently introduced transfer bootstrap support metric.

Availability and implementation

The code is available under GNU GPL at https://github.com/amkozlov/raxml-ng. RAxML-NG web service (maintained by Vital-IT) is available at https://raxml-ng.vital-it.ch/.

Supplementary information

Supplementary data are available at Bioinformatics online.
PubMed Text Similarity Model and its application to curation efforts in the Conserved Domain Database
Authors: Islamaj Rezarta , Wilbur W John , Xie Natalie , Gonzales Noreen R , Thanki Narmada , Yamashita Roxanne , Zheng Chanjuan , Marchler-Bauer Aron , Lu Zhiyong
Published: April 2019

This study proposes a text similarity model to help biocuration efforts of the Conserved Domain Database (CDD). CDD is a curated resource that catalogs annotated multiple sequence alignment models for ancient domains and full-length proteins. These models allow for fast searching and quick identification of conserved motifs in protein sequences via Reverse PSI-BLAST. In addition, CDD curators prepare summaries detailing the function of these conserved domains and specific protein families, based on published peer-reviewed articles. To facilitate information access for database users, it is desirable to specifically identify the referenced articles that support the assertions of curator-composed sentences. Moreover, CDD curators desire an alert system that scans the newly published literature and proposes related articles of relevance to the existing CDD records. Our approach to address these needs is a text similarity method that automatically maps a curator-written statement to candidate sentences extracted from the list of referenced articles, as well as the articles in the PubMed Central database. To evaluate this proposal, we paired CDD description sentences with the top 10 matching sentences from the literature, which were given to curators for review. Through this exercise, we discovered that we were able to map the articles in the reference list to the CDD description statements with an accuracy of 77%. In the dataset that was reviewed by curators, we were able to successfully provide references for 86% of the curator statements. In addition, we suggested new articles for curator review, which were accepted by curators to be added into the reference list at an acceptance rate of 50%. Through this process, we developed a substantial corpus of similar sentences from biomedical articles on protein sequence, structure and function research, which constitute the CDD text similarity corpus. This corpus contains 5159 sentence pairs judged for their similarity on a scale from 1 (low) to 5 (high) doubly annotated by four CDD curators. Curator-assigned similarity scores have a Pearson correlation coefficient of 0.70 and an inter-annotator agreement of 85%. To date, this is the largest biomedical text similarity resource that has been manually judged, evaluated and made publicly available to the community to foster research and development of text similarity algorithms.
Safety, feasibility, and effect of an enhanced nutritional support pathway including extended preoperative and home enteral nutrition in patients undergoing enhanced recovery after esophagectomy: a pilot randomized clinical trial
Authors: Liu K , Ji S , Xu Y , Diao Q , Shao C , Luo J , Zhu Y , Jiang Z , Diao Y , Cong Z , Hu L , Qiang Y , Shen Y
Published: April 2019

The aims of this pilot study are to evaluate the feasibility, safety, and effectiveness of conducting an enhanced nutritional support pathway including extended preoperative nutritional support and one month home enteral nutrition (HEN) for patients who underwent enhanced recovery after esophagectomy. We implemented extended preoperative nutritional support and one month HEN after discharge for patients randomized into an enhanced nutrition group and implemented standard nutritional support for patients randomized into a conventional nutrition group. Except the nutritional support program, both group patients underwent the same standardized enhanced recovery after surgery programs of esophagectomy based on published guidelines. Patients were assessed at preoperative day, postoperative day 7 (POD7), and POD30 for perioperative outcomes and nutritional status. To facilitate the determination of an effect size for subsequent appropriately powered randomized clinical trials and assess the effectiveness, the primary outcome we chose was the weight change before and after esophagectomy. Other outcomes including body mass index (BMI), lean body mass (LBM), appendicular skeletal muscle mass index (ASMI), nutrition-related complications, and quality of life (QoL) were also analyzed. The intention-to-treat analysis of the 50 randomized patients showed that there was no significant difference in baseline characteristics. The weight (−2.03 ± 2.28 kg vs. −4.05 ± 3.13 kg, P = 0.012), BMI (−0.73 ± 0.79 kg/m2 vs. −1.48 ± 1.11 kg/m2, P = 0.008), and ASMI (−1.10 ± 0.37 kg/m2 vs. −1.60 ± 0.66 kg/m2, P = 0.010) loss of patients in the enhanced nutrition group were obviously decreased compared to the conventional nutrition group at POD30. In particular, LBM (48.90 ± 9.69 kg vs. 41.96 ± 9.37 kg, p = 0.031) and ASMI (7.56 ± 1.07 kg/m2 vs. 6.50 ± 0.97 kg/m2, P = 0.003) in the enhanced nutrition group were significantly higher compared to the conventional nutrition group at POD30, despite no significant change between pre- and postoperation. In addition, European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 scores revealed that enhanced nutritional support improved the QoL of patients in physical function (75.13 ± 9.72 vs. 68.33 ± 7.68, P = 0.009) and fatigue symptom (42.27 ± 9.93 vs. 49.07 ± 11.33, P = 0.028) compared to conventional nutritional support. This pilot study demonstrated that an enhanced nutritional support pathway including extended preoperative nutritional support and HEN was feasible, safe, and might be beneficial to patients who underwent enhanced recovery after esophagectomy. An appropriately powered trial is warranted to confirm the efficacy of this approach.
Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial
Authors: White Harvey D , Steg Ph Gabriel , Szarek Michael , Bhatt Deepak L , Bittner Vera A , Diaz Rafael , Edelberg Jay M , Erglis Andrejs , Goodman Shaun G , Hanotin Corinne , Harrington Robert A , Jukema J Wouter , Lopes Renato D , Mahaffey Kenneth W , Moryusef Angele , Pordy Robert , Roe Matthew T , Sritara Piyamitr , Tricoci Pierluigi , Zeiher Andreas M , Schwartz Gregory G ,   ODYSSEY OUTCOMES Investigators
Published: April 2019

Aims 

The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI.

Methods and results 

Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI.

Conclusion 

After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.
Effect of remote monitoring on patient-reported outcomes in European heart failure patients with an implantable cardioverter-defibrillator: primary results of the REMOTE-CIED randomized trial
Authors: Versteeg Henneke , Timmermans Ivy , Widdershoven Jos , Kimman Geert-Jan , Prevot Sébastien , Rauwolf Thomas , Scholten Marcoen F , Zitron Edgar , Mabo Philippe , Denollet Johan , Pedersen Susanne S , Meine Mathias
Published: April 2019

Aims

The European REMOTE-CIED study is the first randomized trial primarily designed to evaluate the effect of remote patient monitoring (RPM) on patient-reported outcomes in the first 2 years after implantation of an implantable cardioverter-defibrillator (ICD).

Methods and results

The sample consisted of 595 European heart failure patients implanted with an ICD compatible with the Boston Scientific LATITUDE® RPM system. Patients were randomized to RPM plus a yearly in-clinic ICD check-up vs. 3–6-month in-clinic check-ups alone. At five points during the 2-year follow-up, patients completed questionnaires including the Kansas City Cardiomyopathy Questionnaire and Florida Patient Acceptance Survey (FPAS) to assess their heart failure-specific health status and ICD acceptance, respectively. Information on clinical status was obtained from patients’ medical records. Linear regression models were used to compare scores between groups over time. Intention-to-treat and per-protocol analyses showed no significant group differences in patients’ health status and ICD acceptance (subscale) scores (all Ps > 0.05). Exploratory subgroup analyses indicated a temporary improvement in device acceptance (FPAS total score) at 6-month follow-up for secondary prophylactic in-clinic patients only (P < 0.001). No other significant subgroup differences were observed.

Conclusion

Large clinical trials have indicated that RPM can safely and effectively replace most in-clinic check-ups of ICD patients. The REMOTE-CIED trial results show that patient-reported health status and ICD acceptance do not differ between patients on RPM and patients receiving in-clinic check-ups alone in the first 2 years after ICD implantation.

ClinicalTrials.gov Identifier: NCT01691586.
Prevalence of atrial fibrillation in the Italian elderly population and projections from 2020 to 2060 for Italy and the European Union: the FAI Project
Authors: Di Carlo Antonio , Bellino Leonardo , Consoli Domenico , Mori Fabio , Zaninelli Augusto , Baldereschi Marzia , Cattarinussi Alessandro , D’Alfonso Maria Grazia , Gradia Chiara , Sgherzi Bruno , Pracucci Giovanni , Piccardi Benedetta , Polizzi Biancamaria , Inzitari Domenico ,   National Research Program: Progetto FAI. La Fibrillazione Atriale in Italia, Aliprandi M L , Bonsangue E , Locatelli P , Saurgnani P , Senziani L G , Tarantini D , Rota Rita Paola , Boninsegni R , Feltrin T , Lancia E , Latella F , Monici G , Portera F , Ceccherini S , Borello G , Contartese A , D’Amico A , D’Urzo G , Grillo G C , Mellea F , Ramondino C
Published: April 2019

Aims

To estimate prevalence of atrial fibrillation (AF) in a representative sample of the Italian elderly population, projecting figures for Italy and the European Union.

Methods and results

A cross-sectional examination of all subjects aged 65+ years from three general practices in Northern, Central, and Southern Italy started in 2016. Participants were administered a systematic and an opportunistic screening, followed by clinical and electrocardiogram confirmation. The study sample included 6016 subjects. Excluding 235 non-eligible, among the remaining 5781 participation was 78.3%, which left 4528 participants (mean age 74.5 ± 6.8 years, 47.2% men). Prevalence of AF was 7.3% [95% confidence intervals (CI) 6.6–8.1], higher in men and with advancing age (6.6% from systematic plus 0.7% from opportunistic screening). Using prevalence figures, Italian elderly having AF in 2016 were estimated at ∼1 081 000 (95% CI 786 000–1 482 000). Considering stable prevalence, this number will increase by 75% to ∼1 892 000 in 2060 (95% CI 1 378 000–2 579 000). European Union elderly having AF in 2016 were estimated at ∼7 617 000 (95% CI 5 530 000–10 460 000), increasing by 89% to ∼14 401 000 in 2060 (95% CI 10 489 000–19 647 000). In 2016, subjects aged 80+ years represented 53.5% of cases in Italy and 51.2% in the European Union; in 2060, 69.6% and 65.2%, respectively.

Conclusions

Our findings indicate a high burden of AF in coming decades, especially among the oldest-old, who carry the higher AF-related risk of stroke and medical complications.