bluuebunny/crossref_metadata_2025 huggingface dataset:
A positive correlation between energetic electron butterfly distributions and magnetosonic waves in the radiation belt slot region
Authors: Yang Chang , Su Zhenpeng , Xiao Fuliang , Zheng Huinan , Wang Yuming , Wang Shui , Spence H. E. , Reeves G. D. , Baker D. N. , Blake J. B. , Funsten H. O.
Published: March 2017

Energetic (hundreds of keV) electrons in the radiation belt slot region have been found to exhibit the butterfly pitch angle distributions. Resonant interactions with magnetosonic and whistler‐mode waves are two potential mechanisms for the formation of these peculiar distributions. Here we perform a statistical study of energetic electron pitch angle distribution characteristics measured by Van Allen Probes in the slot region during a 3 year period from May 2013 to May 2016. Our results show that electron butterfly distributions are closely related to magnetosonic waves rather than to whistler‐mode waves. Both electron butterfly distributions and magnetosonic waves occur more frequently at the geomagnetically active times than at the quiet times. In a statistical sense, more distinct butterfly distributions usually correspond to magnetosonic waves with larger amplitudes and vice versa. The averaged magnetosonic wave amplitude is less than 5 pT in the case of normal and flat‐top distributions with a butterfly index BI =1 but reaches ∼50–95 pT in the case of distinct butterfly distributions with BI >1.3. For magnetosonic waves with amplitudes >50 pT, the occurrence rate of butterfly distribution is above 80%. Our study suggests that energetic electron butterfly distributions in the slot region are primarily caused by magnetosonic waves.
Spacecraft measurements constraining the spatial extent of a magnetopause reconnection X line
Authors: Walsh B. M. , Komar C. M. , Pfau‐Kempf Y.
Published: March 2017

Multispacecraft measurements from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission are used to probe the spatial extent of an X line at the dayside magnetopause. A case study from 21 April 2014 is presented where two THEMIS spacecraft have a near‐simultaneous encounter with the equatorial dayside magnetopause separated by 3.9 Earth radii. Both spacecraft observe similar steady inflow conditions with southward interplanetary magnetic field and a high magnetic shear angle at the magnetopause (133°) boundary. One spacecraft observes clear fluid and kinetic signatures of active magnetic reconnection, while the other spacecraft does not observe reconnection. The predicted location of reconnection across the magnetopause is found using several theoretical models and a Block Adaptive Tree Solarwind Roe‐type Upwind Scheme (BATS‐R‐US) MHD simulation. Each model predicts a continuous X line passing close to the two spacecraft, suggesting both would observe reconnection, if active. Using the constraints of the multipoint measurements, the extent or length L of the reconnection is estimated to be 2.4≤L < 5.2 h in local time or 6≤L< 14 RE.
Thank You to Space Weather Peer Reviewers
Authors: Knipp Delores J. , Hapgood Michael A. , Welling Daniel , Paul O'Brien T.
Published: March 2017

Space Weather Editors recognize peer reviewers.
Identification of photovoltaic arrays' maximum power extraction point via dynamic regressor extension and mixing
Authors: Pyrkin Anton , Mancilla‐David Fernando , Ortega Romeo , Bobtsov Alexey , Aranovskiy Stanislav
Published: March 2017

This paper deals with the problem of identification of photovoltaic arrays' maximum power extraction point—information that is encrypted in the current‐voltage characteristic equation. We propose a new parameterisation of the classical 5 parameter models of this function that, combined with the recently introduced identification technique of dynamic regressor extension and mixing, ensures a fast and accurate estimation of all unknown parameters. A concavity property of the current‐voltage characteristic equation is then exploited to directly identify the desired voltage operating point. Realistic numerical examples via computer simulations are presented to assess the performance of the proposed approach.
Achieving zT > 1 in Inexpensive Zintl Phase Ca9Zn4+xSb9 by Phase Boundary Mapping
Authors: Ohno Saneyuki , Aydemir Umut , Amsler Maximilian , Pöhls Jan‐Hendrik , Chanakian Sevan , Zevalkink Alex , White Mary Anne , Bux Sabah K. , Wolverton Chris , Snyder G. Jeffrey
Published: March 2017

Complex multinary compounds (ternary, quaternary, and higher) offer countless opportunities for discovering new semiconductors for applications such as photovoltaics and thermoelectrics. However, controlling doping has been a major challenge in complex semiconductors as there are many possibilities for charged intrinsic defects (e.g., vacancies, interstitials, antisite defects) whose energy depends on competing impurity phases. Even in compounds with no apparent deviation from a stoichiometric nominal composition, such defects commonly lead to free carrier concentrations in excess of 1020 cm−3. Nevertheless, by slightly altering the nominal composition, these defect concentrations can be tuned with small variation of the chemical potentials (composition) of each element. While the variation of chemical composition is undetectable, it is shown that the changes can be inferred by mapping (in nominal composition space) the boundaries where different competing impurity phases form. In the inexpensive Zintl compound Ca9Zn4+xSb9, the carrier concentrations can be finely tuned within three different three‐phase regions by altering the nominal composition (x = 0.2–0.8), enabling the doubling of thermoelectric performance (zT). Because of the low thermal conductivity, the zT can reach as high as 1.1 at 875 K, which is one of the highest among the earth abundant p‐type thermoelectrics with no ion conducting.
An Engineered Cell‐Instructive Stroma for the Fabrication of a Novel Full Thickness Human Cervix Equivalent In Vitro
Authors: De Gregorio Vincenza , Imparato Giorgia , Urciuolo Francesco , Tornesello Maria L. , Annunziata Clorinda , Buonaguro Franco M. , Netti Paolo A.
Published: March 2017

There is a growing interest for developing organotypic cervical models by using primary cervical cells that are able to reproduce the physiological relevant stromal microenvironment and the distinctive histology of the native cervical epithelium. Here for the first time it is reported the production of an organotypic cervical model featured by a scaffold‐free stromal tissue resembling the extracellular matrix (ECM) composition and organization of the native counterpart as well as a completely well‐differentiated epithelium. To reach this aim, human cervical microtissue precursors have been produced, characterized, and used as functional building units to fabricate a cell‐synthesized cervical stroma equivalent by means of a bottom‐up approach. Immunotypization, and molecular and morphological analyses reveal the extent of fundamental epithelial biomarkers and the presence of collagen and noncollagenous molecules, demonstrating that the natural tissue architecture and biological characteristics of cervical tissues are reproduced. The results of this study suggest that the bottom‐up technology used to produce these 3D human cervical equivalents provides a fully functional organotypic cervical model that may be used as a valuable tool to investigate the epithelial‐stromal interactions as well as for testing new therapeutics in vitro.
Supramolecular Nanostructures of Chiral Perylene Diimides with Amplified Chirality for High‐Performance Chiroptical Sensing
Authors: Shang Xiaobo , Song Inho , Ohtsu Hiroyoshi , Lee Yoon Ho , Zhao Tianming , Kojima Tatsuhiro , Jung Ji Hyung , Kawano Masaki , Oh Joon Hak
Published: March 2017

Chiral supramolecular nanostructures with optoelectronic functions are expected to play a central role in many scientific and technological fields but their practical use remains in its infancy. Here, this paper reports photoconductive chiral organic semiconductors (OSCs) based on perylene diimides with the highest electron mobility among the chiral OSCs and investigates the structure and optoelectronic properties of their homochiral and heterochiral supramolecular assemblies from bottom‐up self‐assembly. Owing to the well‐ordered supramolecular packing, the homochiral nanomaterials exhibit superior charge transport with significantly higher photoresponsivity and dissymmetry factor compared with those of their thin film and monomeric equivalents, which enables highly selective detection of circularly polarized light, for the first time, in visible spectral range. Interestingly, the heterochiral nanostructures assembled from co‐self‐assembly of racemic mixtures show extraordinary chiral self‐discrimination phenomenon, where opposite enantiomeric molecules are packed alternately into heterochiral architectures, leading to completely different optoelectrical performances. In addition, the crystal structures of homochiral and heterochiral nanostructures have first been studied by ab initio X‐ray powder diffraction analysis. These findings give insights into the structure–chiroptical property relationships of chiral supramolecular self‐assemblies and demonstrate the feasibility of supramolecular chirality for high‐performance chiroptical sensing.
Enhancing the Performance of Stretchable Conductors for E‐Textiles by Controlled Ink Permeation
Authors: Jin Hanbit , Matsuhisa Naoji , Lee Sungwon , Abbas Mohammad , Yokota Tomoyuki , Someya Takao
Published: March 2017

Delivery of electronic functionality to the human body using e‐textiles is important for realizing the future of wearable electronics. Printing is a promising process for large scale manufacturing of e‐textile since it enables arbitrary patterns using a simple and inexpensive process. However, conductive inks printed atop of textile are vulnerable to cracking because of the deformable and porous structure of textiles. The authors develop a mechanically and electrically robust wiring by controlling ink permeation in the structure of textile. This is done by adjusting the ink's solvent. The use of butyl carbitol acetate, with its low vapor pressure and boiling point, enables deep permeation into the textile. The sheet resistance is initially 0.06 Ω sq−1, and the resistance increasing only 70 times after stretching to 450% strain. Finally, a four‐channel electromyogram (EMG) monitoring garment is demonstrated to show the potential of a large‐scale e‐textile device for health care and sports.
Anisotropic, Transparent Films with Aligned Cellulose Nanofibers
Authors: Zhu Mingwei , Wang Yilin , Zhu Shuze , Xu Lisha , Jia Chao , Dai Jiaqi , Song Jianwei , Yao Yonggang , Wang Yanbin , Li Yongfeng , Henderson Doug , Luo Wei , Li Heng , Minus Marilyn L. , Li Teng , Hu Liangbing
Published: March 2017

Transparent films or substrates are ubiquitously used in photonics and optoelectronics, with glass and plastics as traditional choice of materials. Transparent films made of cellulose nanofibers are reported recently. However, all these films are isotropic in nature. This work, for the first time, reports a remarkably facile and effective approach to fabricating anisotropic transparent films directly from wood. The resulting films exhibit an array of exceptional optical and mechanical properties. The well‐aligned cellulose nanofibers in natural wood are maintained during delignification, leading to an anisotropic film with high transparency (≈90% transmittance) and huge intensity ratio of transmitted light up to 350%. The anisotropic film with well‐aligned cellulose nanofibers has a mechanical tensile strength of up to 350 MPa, nearly three times of that of a film with randomly distributed cellulose nanofibers. Atomistic mechanics modeling further reveals the dependence of the film mechanical properties on the alignment of cellulose nanofibers through the film thickness direction. This study also demonstrates guided liquid transport in a mesoporous, anisotropic wood film and its possible application in enabling new nanoelectronic devices. These unique and highly desirable properties of the anisotropic transparent film can potentially open up a range of green electronics and nanofluidics.
Fabrication of Sensor Materials Inspired by Butterfly Wings
Authors: Zhu Yucheng , Zhang Wang , Zhang Di
Published: March 2017

The butterfly wing has one of the most complex microstructures in nature. Butterfly wings are known for their reaction towards incident light, which can be attributed to the periodic structure of the scales. A growing number of studies have been performed on butterfly wings, especially the Morpho butterfly family. In this review, the current achievements of biomimetic sensor materials for infrared radiation, thermal radiation, electricity, and magnetism are presented. This review offers new approaches for the design and fabrication of sensor materials.
Pt‐Nanostrip‐Enabled Plasmonically Enhanced Broad Spectral Photodetection in Bilayer MoS2
Authors: Kumar Rahul , Sharma Alka , Kaur Mandeep , Husale Sudhir
Published: March 2017

Hot electron injection in 2D layered materials, in particular graphene or transition metal dichalcogenides, has been the subject of intense research in recent years. The coupling of plasmonic nanostructures with the nanolayers of 2D materials enhances the optoelectronic properties even beyond the bandgap of the material and depends on the tuning of the plasmonic nanomaterials used. In contrast to the Au/Ag mostly used in plasmonic nanostructures, Pt/Pd are more promising for the design of future nano‐plasmonic devices due to their strong catalytic activities and they exhibit a broad localized surface plasmon resonance. Here, plasmonic enhancements in the photoconductivity of bilayer MoS2 induced by Pt nanostrips are reported. About three orders of change in the photocurrent was observed when the plasmonic Pt nanostrips were integrated with the MoS2 and this was measured under illumination with a 532‐nm laser. The fabricated MoS2 devices with Pt nanostrips demonstrated a sensitivity to UV, visible, and NIR light. Numerical analysis shows that the platinum nanostrips exhibit better absorption properties over a broader range of the light spectrum. The electric field enhancements observed at 532 nm and 980 nm clearly indicate that MoS2‐based nanodevices can be tuned with Pt plasmonic nanostructures to achieve high‐performance, ultra‐compact, optoelectronic devices with excellent plasmonic and catalytic activities.
Palladium‐Nanoparticles‐Catalyzed Oxidative Annulation of Benzamides with Alkynes for the Synthesis of Isoquinolones
Authors: Sharma Nidhi , Saha Rajib , Parveen Naziya , Sekar Govindasamy
Published: March 2017

A novel method to synthesize isoquinolones via oxidative annulation of N‐alkoxy benzamides and alkynes using binaphthyl‐stabilized palladium nanoparticles (Pd‐BNP) as catalyst has been developed. This methodology affords various isoquinolone derivatives in good to excellent yields with high regioselectivities in the presence of air as oxidant. N‐Methoxybenzothioamide was also found to undergo oxidative annulation with alkyne successfully and provided a sulfur analogue of isoquinolones in moderate yields. The Pd‐BNP catalyst was easily recovered and reused up to four times without any apparent agglomeration.

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Hypervalent Iodine‐Promoted Aromatization of Exocyclic β‐Enaminones for the Synthesis of meta‐N,N‐Diarylaminophenols
Authors: Bhattacherjee Dhananjay , Thakur Vandna , Shil Arun K. , Das Pralay
Published: March 2017

A metal‐ and additive‐free milder cascade approach for the synthesis of meta‐N,N‐diarylaminophenols (DAAP) starting from exocyclic β‐enaminones has been developed. The feasibility of the process is rationalized by the suitable molecular geometry of β‐enaminones for tandem N‐arylative α‐iodination and aromatization under milder basic conditions. Furthermore, the developed strategy has been extended to the synthesis of meta‐N‐benzyl‐N‐arylaminophenols (BAAP). 4‐Ethylpropionyl‐2‐cyclohexenone has been explored to give 7‐diarylaminochroman‐2‐one (DAAC) by employing a similar one‐pot approach. The plausible mechanistic steps were deduced based upon isolation of a stable intermediate and structural identification through X‐ray crystallographic analysis.

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Depression Among Transgender Older Adults: General and Minority Stress
Authors: Hoy‐Ellis Charles P. , Fredriksen‐Goldsen Karen I.
Published: March 2017

This study aims to (a) examine the direct and indirect effects internalized heterosexism, disclosure of gender identity, and perceived general stress in association with depression among transgender older adults; and (b) to assess the relative contribution of each relationship. Secondary analyses of data from a large community‐based study of older sexual and gender minorities were conducted utilizing structural equation modeling with a subsample (n = 174) of transgender adults aged 50 to 86‐years old. Disclosure of gender identity had no significant direct or indirect effects on either perceived general stress or depression. Internalized heterosexism did not have a direct effect on depression, but did have a significant indirect effect through perceived general stress. Finally, perceived general stress had an additional significant direct effect on depression, over and above internalized heterosexism. Total effect sizes appear to be considerable with standardized betas greater than 5.0. Perceived general stress and internalized heterosexism independently and cumulatively have significant direct and indirect effects on depression among transgender older adults. Implications for depression among transgender older adults and the role of community psychology are discussed.
Molecular analysis of a novel intragenic deletion in GPC3 in three cousins with Simpson–Golabi–Behmel syndrome
Authors: Schmidt Julia , Hollstein Ronja , Kaiser Frank J. , Gillessen‐Kaesbach Gabriele
Published: March 2017

Simpson–Golabi–Behmel syndrome (SGBS) is characterized by multiple congenital abnormalities, pre/postnatal overgrowth, distinctive craniofacial features intellectual disability (ID) of variable degree, and an increased risk for embryonal tumors. SGBS is X‐linked recessive and caused by deletions, duplications, and point mutations in GPC3, encoding a membrane associated cell surface heparan sulfate proteoglycan named glypican 3. GPC3 plays essential roles in the regulation of cell growth signaling and cell division. Here, we report on a family with three affected cousins who show variable clinical signs of SGBS and ID. Initial microarray‐CGH revealed a deletion of approximately 30–50 kb that includes at least one exon of GPC3. By subsequent Sanger sequencing of genomic DNA we could map the chromosomal break points to define a deletion size of 43,617 bp including exons 5 and 6 of the GPC3 gene. RT‐PCR analysis on RNA derived from whole blood could further confirm the deletion of both exons on transcript level. This loss of two exons results in a frameshift and a premature stop of translation. Based on our results we have established a breakpoint spanning PCR that could identify the mutation in the mothers and grandmother of the patients. Thus, we provided a molecular test that allows accurate genetic counselling and prenatal diagnosis for this family.
Nitroarenes as the Nitrogen Source in Intermolecular Palladium‐Catalyzed Aryl C–H Bond Aminocarbonylation Reactions
Authors: Zhou Fei , Wang Duo‐Sheng , Guan Xinyu , Driver Tom G.
Published: March 2017

A three‐component palladium‐catalyzed aminocarbonylation of aryl and heteroaryl sp2 C−H bonds using nitroarenes as the nitrogen source was achieved using Mo(CO)6 as the reductant and origin of the CO. This intermolecular C−H bond functionalization does not requires any exogenous ligand to be added, and our mechanism experiments indicate that the palladacycle catalyst serves two roles in the aminocarbonylation reaction: reduce the nitroarene to a nitrosoarene and activate the sp2 C−H bond.
Biocatalysis in Silicon Chemistry
Authors: Frampton Mark B. , Zelisko Paul M.
Published: March 2017

The application of biocatalytic or chemoenzymatic techniques in silicon chemistry serves two roles: it provides a greater understanding of the processing of silicon species by natural systems, such as plants, diatoms, and sponges, as well opening up avenues to green methodologies in the field. In the latter case, biocatalytic approaches have been applied to the synthesis of small‐molecule systems and polymeric materials. Often these biocatalytic approaches allow access to molecular structures under mild conditions and, in some cases, molecular structures that are not accessible through traditional chemical methodologies. A review of recent advances in the applications of biocatalysis in silicon chemistry is presented.
Minimum Energy Control of Fractional Descriptor Discrete‐Time Linear Systems with Bounded Inputs Using The DRAZIN Inverse
Authors: Kaczorek Tadeusz
Published: March 2017

The Drazin inverse of matrices is applied to solve the minimum energy control problem of fractional descriptor discrete‐time linear systems with bounded inputs. Necessary and sufficient conditions for the reachability of fractional descriptor linear systems are established. The minimum energy control problem for the fractional descriptor systems with bounded inputs is formulated and solved. A procedure for the computation of the optimal inputs sequence and the minimal value of the performance index is proposed.
Central nervous system involvement of acute promyelocytic leukemia, three case reports
Authors: Furuya Aya , Kawahara Masahiro , Kumode Mina , Ohira Yasuyuki , Usui Asako , Nagai Shiho , Hosoba Sakura , Minamiguchi Hitoshi , Kito Katsuyuki , Andoh Akira
Published: March 2017

Key Clinical Message

Central nervous system (CNS) involvement of acute promyelocytic leukemia (APL) causes poor prognosis. Our three cases show that CNS can be involved at the first hematological recurrence, but predicting this is difficult. Triple intrathecal treatment and craniospinal irradiation were effective, while arsenic oxide failed to prevent and improve CNS involvement.
The Role of Various Chlorides on Xylose Conversion to Furfural: Experiments and Kinetic Modeling
Authors: Ershova Olga , Nieminen Kaarlo , Sixta Herbert
Published: March 2017

In this paper, the catalytic activity of thirteen different metal chlorides in aqueous solution for the conversion of xylose into furfural was studied in comparison with both the auto‐ and HCl‐catalyzed reactions. A maximum furfural yield of 60.3 mol % was reached with the addition of FeCl3 to the aqueous xylose solution. However, the catalytic efficiency of FeCl3 decreased on use of birch hydrolysate as a raw material, resulting in 43.5 mol % furfural yield. The obtained experimental results were incorporated in a kinetic modeling study. The assessed reaction rates for xylose dehydration to furfural and xylose decomposition to byproducts, in the presence of AlCl3 and CrCl3 are significantly higher than during acid‐catalyzed conversion. The logarithms of the reaction rates show a linear correlation with the ionization energy as well as with the acidity of the metal ions.
Enzyme‐Promoted Asymmetric Tandem Passerini Reaction
Authors: Żądło‐Dobrowolska Anna , Koszelewski Dominik , Paprocki Daniel , Madej Arleta , Wilk Monika , Ostaszewski Ryszard
Published: March 2017

A versatile and highly efficient three‐step, one‐pot, enzyme‐promoted Passerini tandem reaction has been developed. The chemoenzymatic sequence involved simultaneous enzyme catalyzed hydrolysis, subsequent Passerini reaction, and enzymatic kinetic resolution of the Passerini product. This methodology combines the diversity delivered by multicomponent reactions with the selectivity of biocatalysts, which results in efficient synthesis of the target compounds with excellent enantiomeric excesses of up to 99 %. With a small set of substrates, a large library of complex molecules was obtained within a short time by using the developed procedure.
Catalysis of Michael Additions by Covalently Modified G‐Quadruplex DNA
Authors: Dey Surjendu , Rühl Carmen L. , Jäschke Andres
Published: March 2017

Enantioselective catalysis utilizing G‐quadruplex DNA‐based artificial metalloenzymes has emerged as a new approach in the field of aqueous‐phase homogeneous catalysis. Recently, a catalytic asymmetric Michael addition employing a covalently modified G‐quadruplex in combination with CuII ions has been reported. Here we assess, by systematic chemical variation and using various spectrometric techniques, a variety of parameters that govern rate acceleration and stereoselectivity of the reaction, such as the position of modification, the topology of the quadruplex, the nature of the ligand, the length of the linker between ligand and DNA, the chemical identity of monovalent ions and transition metal complexes. The DNA quadruplex modified at position 10 (dU10) with hexynyl‐linked bpy ligand showed twice the initial reaction rate as compared with the DNA strand derivatized at position 12 (dU12). The strikingly different dependence of the stereoselectivity on the linker length, and their different spectroscopic properties indicate large differences in the architecture of the catalytic centers between the dU10‐derivatized and the dU12‐modified quadruplexes. Upon addition of CuII, both types of bpy‐derivatized DNA strands form defined 1:1 Cu–DNA complexes stable enough for mass spectrometric analysis, while the underivatized strands exhibit weak and unspecific binding, correlated with much lower catalytic rate acceleration. Both dU10‐ and dU12‐derivatized quadruplexes could be reused ten times without reduction of stereoselectivity.
Hydroxylated Fluorescent Dyes for Live‐Cell Labeling: Synthesis, Spectra and Super‐Resolution STED
Authors: Butkevich Alexey N. , Belov Vladimir N. , Kolmakov Kirill , Sokolov Viktor V. , Shojaei Heydar , Sidenstein Sven C. , Kamin Dirk , Matthias Jessica , Vlijm Rifka , Engelhardt Johann , Hell Stefan W.
Published: March 2017

Hydroxylated rhodamines, carbopyronines, silico‐ and germanorhodamines with absorption maxima in the range of 530–640 nm were prepared and applied in specific labeling of living cells. The direct and high‐yielding entry to germa‐ and silaxanthones tolerates the presence of protected heteroatoms and may be considered for the syntheses of various sila‐ and germafluoresceins, as well as ‐rhodols. Application in stimulated emission depletion (STED) fluorescence microscopy revealed a resolution of 50–75 nm in one‐ and two‐color imaging of vimentin‐HaloTag fused protein and native tubulin. The established structure–property relationships allow for prediction of the spectral properties and the positions of spirolactone/zwitterion equilibria for the new analogues of rhodamines, carbo‐, silico‐, and germanorhodamines using simple additive schemes.
Thermal effects in guest–host systems: [Zn2(bdc)(S‐lac)(dmf)]•PhEtOH: A DSC and NMR study
Authors: Kozlova Svetlana G. , Pishchur Denis P. , Gallyamov Marsel R.
Published: March 2017

Differential scanning calorimetry and nuclear magnetic resonance were used to investigate thermal effects in the guest–host systems where homochiral metal–organic sorbent [Zn2(bdc)(S‐lac)(dmf)] is considered as a host while 1‐phenylethanol enantiomers and their racemic mixture serve as guest molecules. A maximum energy gain from the guest–host interaction was observed in the system with the racemic mixture. The effect of host–guest recognition was revealed for the case of the host and guest having a similar type of chirality in the presence of antipode guest molecules.
Structure‐Based Target‐Specific Screening Leads to Small‐Molecule CaMKII Inhibitors
Authors: Xu David , Li Liwei , Zhou Donghui , Liu Degang , Hudmon Andy , Meroueh Samy O.
Published: March 2017

Target‐specific scoring methods are more commonly used to identify small‐molecule inhibitors among compounds docked to a target of interest. Top candidates that emerge from these methods have rarely been tested for activity and specificity across a family of proteins. In this study we docked a chemical library into CaMKIIδ, a member of the Ca2+/calmodulin (CaM)‐dependent protein kinase (CaMK) family, and re‐scored the resulting protein–compound structures using Support Vector Machine SPecific (SVMSP), a target‐specific method that we developed previously. Among the 35 selected candidates, three hits were identified, such as quinazoline compound 1 (KIN‐1; N4‐[7‐chloro‐2‐[(E)‐styryl]quinazolin‐4‐yl]‐N1,N1‐diethylpentane‐1,4‐diamine), which was found to inhibit CaMKIIδ kinase activity at single‐digit micromolar IC50. Activity across the kinome was assessed by profiling analogues of 1, namely 6 (KIN‐236; N4‐[7‐chloro‐2‐[(E)‐2‐(2‐chloro‐4,5‐dimethoxyphenyl)vinyl]quinazolin‐4‐yl]‐N1,N1‐diethylpentane‐1,4‐diamine), and an analogue of hit compound 2 (KIN‐15; 2‐[4‐[(E)‐[(5‐bromobenzofuran‐2‐carbonyl)hydrazono]methyl]‐2‐chloro‐6‐methoxyphenoxy]acetic acid), namely 14 (KIN‐332; N‐[(E)‐[4‐(2‐anilino‐2‐oxoethoxy)‐3‐chlorophenyl]methyleneamino]benzofuran‐2‐carboxamide), against 337 kinases. Interestingly, for compound 6, CaMKIIδ and homologue CaMKIIγ were among the top ten targets. Among the top 25 targets of 6, IC50 values ranged from 5 to 22 μm. Compound 14 was found to be not specific toward CaMKII kinases, but it does inhibit two kinases with sub‐micromolar IC50 values among the top 25. Derivatives of 1 were tested against several kinases including several members of the CaMK family. These data afforded a limited structure–activity relationship study. Molecular dynamics simulations with explicit solvent followed by end‐point MM‐GBSA free‐energy calculations revealed strong engagement of specific residues within the ATP binding pocket, and also changes in the dynamics as a result of binding. This work suggests that target‐specific scoring approaches such as SVMSP may hold promise for the identification of small‐molecule kinase inhibitors that exhibit some level of specificity toward the target of interest across a large number of proteins.
Real‐time surveillance detection system for medium‐altitude long‐endurance unmanned aerial vehicles
Authors: Amanatiadis Angelos , Bampis Loukas , Karakasis Evangelos G. , Gasteratos Antonios , Sirakoulis Georgios
Published: March 2017

The detection of ambiguous objects, although challenging, is of great importance for any surveillance system and especially for an unmanned aerial vehicle, where the measurements are affected by the great observing distance. Wildfire outbursts and illegal migration are only some of the examples that such a system should distinguish and report to the appropriate authorities. More specifically, Southern European countries commonly suffer from those problems due to the mountainous terrain and thick forests that contain. Unmanned aerial vehicles like the “Hellenic Civil Unmanned Air Vehicle” project have been designed to address high‐altitude detection tasks and patrol the borders and woodlands for any ambiguous activity. In this paper, a moment‐based blob detection approach is proposed that uses the thermal footprint obtained from single infrared images and distinguishes human‐ or fire‐sized and shaped figures. Our method is specifically designed so as to be appropriately integrated into hardware acceleration devices, such as General Purpose Computation on Graphics Processing Units (GPGPUs) and field programmable gate arrays, and takes full advantage of their respective parallelization capabilities succeeding real‐time performances and energy efficiency. The timing evaluation of the proposed hardware accelerated algorithm's adaptations shows an achieved speedup of up to 7 times, as compared to a highly optimized CPU‐only based version.
Self‐Assembly of Spinel Nanocrystals into Mesoporous Spheres as Bifunctionally Active Oxygen Reduction and Evolution Electrocatalysts
Authors: Lee Dong Un , Li Jingde , Park Moon Gyu , Seo Min Ho , Ahn Wook , Stadelmann Ian , Ricardez‐Sandoval Luis , Chen Zhongwei
Published: March 2017

The present work introduces spinel oxide nanocrystals self‐assembled into mesoporous spheres that are bifunctionally active towards catalyzing both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). The electrochemical evaluation reveals that (Ni,Co)3O4 demonstrates a significantly positive‐shifted ORR onset and half‐wave potentials [−0.127 and −0.292 V vs. saturated calomel electrode (SCE), respectively], whereas Co3O4 results in a negative‐shifted OER potential (0.65 V vs. SCE) measured at 10 mA cm−2. Based on the DFT analysis, the potential at which all oxygen intermediate reactions proceed spontaneously is the highest for (Ni,Co)3O4 (U=0.66 eV) during ORR, whereas it is the lowest for Co3O4 (U=2.09 eV) during OER. The high ORR activity of (Ni,Co)3O4 is attributed to the enhanced electrical conductivity of the spinel lattice, and the high OER activity of Co3O4 is attributed to relatively weak adsorption energy promoting rapid release of evolved oxygen.
Heavily Boron Doped Diamond Electrodes for Ultra Sensitive Determination of Ciprofloxacin in Human Urine
Authors: Radičová Monika , Behúl Miroslav , Marton Marián , Vojs Marian , Bodor Róbert , Redhammer Robert , Vojs Staňová Andrea
Published: March 2017

Ciprofloxacin is one of the most potent fluoroquinolone antibiotics in medical treatment with a widely effective antibacterial activity. Aim of the presented paper was to use boron doped diamond electrodes for a sensitive, simple and reliable voltammetric determination of ciprofloxacin in human urine samples. Prior to the electrochemical analyses, an optimal boron doping level was determined in order to achieve the highest sensitivity. A set of boron doped diamond electrodes with the doping level in the range from 0 to 20 000 ppm B/C was used for this purpose. Electrochemical behavior of ciprofloxacin was investigated using cyclic voltammetry in an ammonium acetate buffer (pH 5), where ciprofloxacin provided a well‐defined irreversible oxidation peak at a potential of + 1.15 V. Under optimal experimental conditions, the calibration curve obtained by square‐wave voltammetry was linear in a concentration range from 0.15 to 2.11 μmol/L (R2=0.9974). A very low limit of detection (0.05 μmol/L) was obtained for the BDD electrode with the highest doping level. The developed square wave method was successfully applied to the determination of ciprofloxacin in human urine samples with a very good recovery (from 97 to 102%).
PTHrP(12-48) Modulates the Bone Marrow Microenvironment and Suppresses Human Osteoclast Differentiation and Lifespan
Authors: Kamalakar Archana , Washam Charity L , Akel Nisreen S , Allen Bethany J , Williams Diarra K , Swain Frances L , Leitzel Kim , Lipton Allan , Gaddy Dana , Suva Larry J
Published: March 2017

Bone is a common site for metastasis in breast cancer patients and is associated with a series of complications that significantly compromise patient survival, partially due to the advanced stage of disease at the time of detection. Currently, no clinically-approved biomarkers can identify or predict the development of bone metastasis. We recently identified a unique peptide fragment of parathyroid hormone-related protein (PTHrP), PTHrP(12-48), as a validated serum biomarker in breast cancer patients that correlates with and predicts the presence of bone metastases. In this study, the biological activity and mode of action of PTHrP(12-48) was investigated. Sequence-based and structure-based bioinformatics techniques predicted that the PTHrP(12-48) fragment formed an alpha helical core followed by an unstructured region after residue 40 or 42. Thereafter, detailed structure alignment and molecular docking simulations predicted a lack of interaction between PTHrP(12-48) and the cognate PTH1 receptor (PTHR1). The in silico prediction was confirmed by the lack of PTHrP(12-48)-stimulated cAMP accumulation in PTHR1-expressing human SaOS2 cells. Using a specific human PTHrP(12-48) antibody that we developed, PTHrP(12-48) was immunolocalized in primary and bone metastatic human breast cancer cells, as well as within human osteoclasts (OCLs) in bone metastasis biopsies, with little or no localization in other resident bone or bone marrow cells. In vitro, PTHrP(12-48) was internalized into cultured primary human OCLs and their precursors within 60 min. Interestingly, PTHrP(12-48) treatment dose-dependently suppressed osteoclastogenesis, via the induction of apoptosis in both OCL precursors as well as in mature OCLs, as measured by the activation of cleaved caspase 3. Collectively, these data suggest that PTHrP(12-48) is a bioactive breast cancer–derived peptide that locally regulates the differentiation of hematopoietic cells and the activity of osteoclasts within the tumor–bone marrow microenvironment, perhaps to facilitate tumor control of bone. © 2017 American Society for Bone and Mineral Research.
Induced Retro‐Differentiation of Human Retinal Pigment Epithelial Cells on PolyHEMA
Authors: Nazemroaya Fatemeh , Soheili Zahra‐Soheila , Samiei Shahram , Deezagi Abdolkhalegh , Ahmadieh Hamid , Davari Malihe , Heidari Razeih , Bagheri Abouzar , Darvishalipour‐Astaneh Shamila
Published: March 2017

Retinal pigment epithelium (RPE) cells represent a great potential to rescue degenerated cells of the damaged retina. Activation of the virtually plastic properties of RPE cells may aid in recovery of retinal degenerative disorders without the need for entire RPE sheet transplantation. Poly (2‐hydroxyethyl methacrylate)(PolyHEMA) is one of the most important hydrogels in the biomaterials world. This hydrophobic polymer does not normally support attachment of mammalian cells. In the current study we investigated the effect of PolyHEMA as a cell culture substrate on the growth, differentiation, and plasticity of hRPE cells. hRPE cells were isolated from neonatal human globes and cultured on PolyHEMA and polystyrene substrates (as controls) in 24‐well culture plates. DMEM/F12 was supplemented with 10% fetal bovine serum (FBS) and/or 30% human amniotic fluid (HAF) for cultured cells on polystyrene and PolyHEMA coated vessels. Morphology, rate of cell proliferation and cell death, MTT assay, immunocytochemistry and Real‐Time RT‐PCR were performed to investigate the effects of PolyHEMA on the growth and differentiation of cultured hRPE cells. Proliferation rate of the cells that had been cultured on PolyHEMA was reduced; PolyHEMA did not induce cell death in the hRPE cultures. hRPE cells cultured on PolyHEMA formed many giant spheroid colonies. The giant colonies were re‐cultured and the presence of retinal progenitor markers and markers of hRPE cells were detected in cell cultures on PolyHEMA. PolyHEMA seems to be promising for both maintenance and de‐differentiation of hRPE cells and expansion of the retinal progenitor cells from the cultures that are originated from hRPE cells. J. Cell. Biochem. 118: 3080–3089, 2017. © 2017 Wiley Periodicals, Inc.
Ombitasvir/paritaprevir/ritonavir/dasabuvir ± ribavirin is safe and effective in HCV‐infected patients in a real‐life cohort from Latin America
Authors: Mendizabal Manuel , Haddad Leila , Gallardo Patricia E. , Ferrada Alejandro , Soza Alejandro A. , Adrover Raul , Aravena Edmundo , Roblero Juan P. , Prieto Jhon , Vujacich Claudia , Romero Gustavo , Muñoz Alberto , Anders Margarita , Hernández Nelia , Coccozella Daniel , Gruz Fernando , Reggiardo Maria V. , Ruf Andres E. , Varón Adriana , Cartier Mariano , Pérez Ravier Roberto , Ridruejo Ezequiel , Peralta Mirta , Poncino Daniel , Vorobioff Julio , Aballay Soteras Gabriel , Silva Marcelo O.
Published: March 2017

Information about the use of ombitasvir/paritaprevir/ritonavir/dasabuvir ± ribavirin (OBV/PTV/r/DSV ± RBV) in real‐clinical practice in Latin America is scarce. We aimed to confirm safety and effectiveness of OBV/PTV/r/DSV ± RBV therapy in real‐world setting. We analyzed a cohort of patients with genotype 1 infection treated with OBV/PTV/r/DSV ± RBV. Data on demographics, clinical features, safety, and virological response were retrospectively collected from 21 centers in Latin America. A total of 96 patients received OBV/PTV/r/DSV, associated with RBV in 68% of the cases. Most were genotype 1b (80%), 56 (58%) had cirrhosis, and 45 (47%) failed prior HCV treatment. Adverse events occurred in 62% of patients. The most common adverse events were pruritus (21%), hyperbilirubinemia (17%), and asthenia (17%). Five patients discontinued therapy prematurely due to hepatic decompensation, three of them were Child‐Pugh B at baseline and one patient died due to multi‐organ failure. Follow up HCV‐RNA 12 weeks after completion of therapy was evaluated in all the patients and sustained virologic response rate was 97%. No virologic breakthrough was detected. Our study confirms that OBV/PTV/r/DSV treatment is highly effective in patients with chronic HCV without cirrhosis or with Child‐Pugh A cirrhosis in non‐European populations. Adverse events were often mild and rarely led to treatment discontinuation except for patients with Child‐Pugh B cirrhosis or with previous history of hepatic decompensation. These results can support the development of public strategies to expand the access of OBV/PTV/r + DSV and other DAAs combinations in order to reduce the burden of HCV infection in our region.
Evaporation modelling using different machine learning techniques
Authors: Wang Lunche , Kisi Ozgur , Hu Bo , Bilal Muhammad , Zounemat‐Kermani Mohammad , Li Hui
Published: March 2017

Accurate prediction of pan evaporation (Ep) is critical for water resource management. This article investigates the capabilities of three different soft computing methods at estimating monthly Ep at six stations in the Yangtze River Basin using climatic factors, including the air temperature (Ta), solar radiation (Rg), air pressure (Pa) and wind speed (Ws) for the period of 1961–2000. The first part of the study focused on testing and comparing model accuracy levels at each station using local input combinations. The results indicate that the fuzzy genetic (FG) model generally produces better results than adaptive neuro‐fuzzy inference systems with grid partition (ANFIS‐GP) and M5 model tree (M5Tree) specifications in terms of the root mean square error , mean absolute error and coefficient of determination values. The performance of the above models was also examined using cross‐station applications (estimating Ep without local input or output data) in the second part of the study. The third part focused on estimating Ep using generalized FG, ANFIS‐GP and M5Tree models. Collectively, the results demonstrate that the FG model can be successfully used to estimate Ep without any local inputs and outputs and that a single generalized FG model can also be used at six different locations.
Influences of the seasonal growth of vegetation on surface energy budgets over middle to high latitudes
Authors: Zhu Jiawen , Zeng Xiaodong
Published: March 2017

The feedbacks of vegetation growth to climate are very important and exhibit large differences, depending on seasons and characteristics of plants and climate. Through two simulations, this work investigated these differences among the influences of the seasonal growth of different vegetation on surface energy budgets over the latitudinal range of 30–90°N and detected associated causes. The seasonal growth of vegetation is expressed as an increase in leaf area index (LAI) during the growing season (April–October) compared to boreal winter (December–January–February). The results showed that notable effects occurred in latent heat flux, downward solar radiation and reflected solar radiation for dominant plant functional types (PFTs). With a seasonal increase in LAI, the latent heat flux of ‘needleleaf evergreen boreal tree’ (NEB) decreased, while it increased for the other dominant PFTs. Such unexpected behaviours of NEB were mainly contributed by the weak changes in its transpiration, which was associated to land‐atmosphere feedbacks (the decreased downward solar radiation) and competitions among PFTs (the intensified transpirations of the deciduous vegetation PFTs). Surface downward solar radiation decreased for all dominant vegetation PFTs because of more low clouds. The reflected solar radiation of ‘broadleaf deciduous temperate tree’ increased along with increased LAI because its leaf albedo is higher than that of the background soil, and the reflected solar radiation of ‘broadleaf deciduous boreal shrub’ drastically decreased during April and May, which resulted from its interactions with accumulated snow. This paper sufficiently proves that the feedbacks of different vegetation to surface energy balance could vary widely, not only in magnitudes but also in directions. Therefore, it is very important to accurately parameterize vegetation phenology and optical properties for a better representation of vegetation–climate interactions.
Retracted: Southward migrations of the Atlantic Equatorial Currents during the Younger Dryas
Authors: Zou Youjia , Xi Xiangying , Zhang Chaoyang
Published: March 2017

Previous studies suggested that a weakened Gulf Stream may have contributed to the Younger Dryas (YD) cold event, however the physical mechanism of the Gulf Stream weakening is unclear. Here, we utilize paired Mg/Ca and δ18O measurements of planktonic foraminifera from the northerly and southerly marine sediments in the middle Atlantic Ocean to reconstruct past changes in tropical surface ocean temperature and salinity over the past 14 ka. We demonstrate that during the YD the sea surface temperature (SST) at the northerly core (0°16′S) was up to 2.1–2.7°C cooler whereas the SST at the southerly core (14°53′S) was up to 0.8–1.6°C warmer than modern temperatures. The δ18O, salinity values, accumulation rates, and other hydrological elements at the northerly core all exhibit opposite patterns with those at the southerly core. The antiphased variations of the paleohydrological elements at the northerly and southerly cores suggest that the Atlantic Equatorial Currents shifted southward significantly from its present‐day position during the YD, possibly resulting in a decrease of the Gulf Stream, in turn a cool Northern Hemisphere.
A model of phototrophic sulfide oxidation in a stratified estuary
Authors: Findlay Alyssa J. , Di Toro Dominic M. , Luther George W.
Published: March 2017

Sulfide accumulated as a result of microbial sulfate reduction in sediments and the bottom waters of stratified systems can be re‐oxidized via an array of biotic and abiotic reactions. A one‐dimensional diffusion‐reaction model was developed and applied to 4 yr of physical and chemical data from the stratified water column of the Chesapeake Bay in order to quantify the impact of different sulfide oxidation processes at the redox interface during slack tide. This dataset and the model simulations highlight short‐term and interannual variation in the physical structure and the distribution of key redox species (O2, H2S, S0, Fe2+, Mn2+, FeOOH, MnO2) throughout the water column. The model evaluates links between oxygen, sulfur, iron and manganese cycling, and includes the novel consideration of sulfide oxidation by phototrophic sulfide oxidizing bacteria (PSOB), which are a common component of the Bay. Model simulations demonstrate that phototrophic sulfide oxidation can account for up to 58% of total sulfide oxidation, depending upon the depth of the oxic/anoxic interface. The results of this study yield an approach to parameterizing PSOB activity, and quantify the variable role that PSOB play in sulfide oxidation in the Chesapeake Bay as redox conditions in the water column change, which has applications for both modern and ancient environments.