bluuebunny/crossref_metadata_2025_split huggingface dataset:
In situ viscoelastic properties and chain conformations of heavily hydrated carboxymethyl dextran layers: a comparative study using OWLS and QCM-I chips coated with waveguide material
Authors: Saftics Andras , Prósz György Aurél , Türk Barbara , Peter Beatrix , Kurunczi Sándor , Horvath Robert 
Published: August 2018

AbstractHydration, viscoelastic properties and dominant structure of thin polymer layers on the surface of waveguide material were evaluated using optical waveguide lightmode spectroscopy (OWLS) and quartz crystal microbalance (QCM) methods. The fundamentally different principles of the two applied label-free biosensors enable to examine analyte layers from complementary aspects, e.g. to determine the amount of bound water in hydrated layers. In this study, a new QCM instrument with impedance measurement (QCM-I) is introduced. Its specially designed sensor chips, covered by thin film of waveguide material, supply identical surface as used in OWLS sensors, thus enabling to perform parallel measurements on the same type of surface. Viscoelastic analysis of the measured data was performed by our evaluation code developed in MATLAB environment, using the Voinova’s Voigt-based model. In situ deposition experiments on the ultrathin films of poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) were conducted for instrumental and code validation. Additionally, a novel OWLS-QCM data evaluation methodology has been developed based on the concept of combining hydration and viscoelastic data with optical anisotropy results from OWLS measurements. This methodology provided insight into the time-dependent chain conformation of heavily hydrated nano-scaled layers, resulting in unprecedented structural, hydration and viscoelastic information on covalently grafted ultrathin carboxymethyl dextran (CMD) films. The measured mass values as well as hydration and viscoelastic properties were compared with the characteristics of PLL-g-PEG layers.
Intrinsically active MEK variants are differentially regulated by proteinases and phosphatases
Authors: Ordan Merav , Pallara Chiara , Maik-Rachline Galia , Hanoch Tamar , Gervasio Francesco Luigi , Glaser Fabian , Fernandez-Recio Juan , Seger Rony 
Published: August 2018

AbstractMAPK/ERK kinase (MEK) 1/2 are central signaling proteins that serve as specificity determinants of the MAPK/ERK cascade. More than twenty activating mutations have been reported for MEK1/2, and many of them are known to cause diseases such as cancers, arteriovenous malformation and RASopathies. Changes in their intrinsic activity do not seem to correlate with the severity of the diseases. Here we studied four MEK1/2 mutations using biochemical and molecular dynamic methods. Although the studied mutants elevated the activating phosphorylation of MEK they had no effect on the stimulated ERK1/2 phosphorylation. Studying the regulatory mechanism that may explain this lack of effect, we found that one type of mutation affects MEK stability and two types of mutations demonstrate a reduced sensitivity to PP2A. Together, our results indicate that some MEK mutations exert their function not only by their elevated intrinsic activity, but also by modulation of regulatory elements such as protein stability or dephosphorylation.
Reduced post-operative DPP4 activity associated with worse patient outcome after cardiac surgery
Authors: Noels Heidi , Theelen Wendy , Sternkopf Marieke , Jankowski Vera , Moellmann Julia , Kraemer Sandra , Lehrke Michael , Marx Nikolaus , Martin Lukas , Marx Gernot , Jankowski Joachim , Goetzenich Andreas , Stoppe Christian 
Published: August 2018

AbstractCardiac surgery with cardiopulmonary bypass (CPB) triggers myocardial ischemia/reperfusion injury contributing to organ dysfunction. Preclinical studies revealed that dipeptidyl peptidase (DPP4) inhibition is protective during myocardial infarction. Here, we assessed for the first time the relation of peri-operative DPP4-activity in serum of 46 patients undergoing cardiac surgery with patients’ post-operative organ dysfunction during intensive care unit (ICU) stay. Whereas a prior myocardial infarction significantly reduced pre-operative DDP4-activity, patients with preserved left ventricular function showed an intra-operative decrease of DPP4-activity. The latter correlated with aortic cross clamping time, indicative for the duration of surgery-induced myocardial ischemia. As underlying mechanism, mass-spectrometry revealed increased DPP4 oxidation by cardiac surgery, with DPP4 oxidation reducing DPP4-activityin vitro. Further, post-operative DPP4-activity was negatively correlated with the extent of post-operative organ injury as measured by SAPS II and SOFA scoring, circulating levels of creatinine and lactate, as well as patients’ stay on the ICU. In conclusion, cardiac surgery reduces DPP4-activity through oxidation, with low post-operative DPP4-activity being associated with organ dysfunction and worse outcome of patients during the post-operative ICU stay. This likely reflects the severity of myocardial ischemia/reperfusion injury and may suggest potential beneficial effects of anti-oxidative treatments during cardiac surgery.
Understanding of MoS2/GaN Heterojunction Diode and its Photodetection Properties
Authors: Moun Monika , Kumar Mukesh , Garg Manjari , Pathak Ravi , Singh Rajendra 
Published: August 2018

AbstractFabrication of heterojunction between 2D molybdenum disulfide (MoS2) and gallium nitride (GaN) and its photodetection properties have been reported in the present work. Surface potential mapping at the MoS2/GaN heterojunction is done using Kelvin Probe Force Microscopy to measure the conduction band offset. Current-voltage measurements show a diode like behavior of the heterojunction. The origin of diode like behavior is attributed to unique type II band alignment of the heterojunction. The photocurrent, photoresponsivity and detectivity of the heterojunction are found to be dependent on power density of the light. Photoresponse investigations reveal that the heterojunction is highly sensitive to 405 nm laser with very high responsivity up to 105 A/W. The heterojunction also shows very high detectivity of the order of 1014 Jones. Moreover, the device shows photoresponse in UV region also. These observations suggest that MoS2/GaN heterojunction can have great potential for photodetection applications.
The potency of the broad spectrum bacteriocin, bactofencin A, against staphylococci is highly dependent on primary structure, N-terminal charge and disulphide formation
Authors: O’ Connor Paula M. , O’ Shea Eileen F. , Cotter Paul D. , Hill Colin , Ross R. Paul 
Published: August 2018

AbstractBactofencin A is a novel class IId bacteriocin, produced by the intestinal isolate Lactobacillus salivarius DPC6502, which has potent activity against medically significant pathogens including Staphylococcus aureus. This bacteriocin is unusual in that it has a highly cationic N terminus and a single disulfide bond between Cys7 and Cys22, resulting in a large C terminal loop. In this study, a library of synthetic bactofencin A variants were screened against the mastitis isolate, S. aureus DPC5246, to identify key residues responsible for activity. It was apparent that substituting either cysteine of the disulfide bond with either serine or alanine significantly reduced the activity of the bacteriocin, confirming the importance of the C terminal loop. Substituting N terminal amino acids with alanine had no effect on activity, whereas sequential removal of the N terminal positively charged residues resulted in an increasingly inactive peptide. A complete (synthetic) alanine scanning analysis revealed that the residues between Val9 and Gly17 were most affected by substitution suggesting that this area has a major influence on the potency of the bacteriocin. Substituting residues in the loop region between Cys7 and Cys22 for D-amino acid equivalents had a more detrimental effect on activity than L-alanine substitutions. Specifically Y10A, N11A, P15A and T16A are active at 4, 16, 1 and 16 μM respectively while their D equivalents were inactive at 1000 μM, the highest concentration tested. Ultimately, this study identifies the critical features in the primary structure of the bacteriocin which gives it such potent activity against pathogenic staphylococci.
Charged giant unilamellar vesicles prepared by electroformation exhibit nanotubes and transbilayer lipid asymmetry
Authors: Steinkühler Jan , De Tillieux Philippe , Knorr Roland L. , Lipowsky Reinhard , Dimova Rumiana 
Published: August 2018

AbstractGiant unilamellar vesicles (GUVs) are increasingly used as a versatile research tool to investigate membrane structure, morphology and phase state. In these studies, GUV preparation is typically enhanced by an externally applied electric field, a process called electroformation. We find that upon osmotic deflation, GUVs electroformed from charged and neutral lipids exhibit inward pointing lipid nanotubes, suggesting negative spontaneous curvature of the membrane. By quenching a fluorescent analog of the charged lipid, zeta potential measurements and experiments with the lipid marker annexin A5, we show that electroformed GUVs exhibit an asymmetric lipid distribution across the bilayer leaflets. The asymmetry is lost either after storing electroformed GUVs at room temperature for one day or by applying higher voltages and temperatures during electroformation. GUVs having the same lipid composition but grown via gel-assisted swelling do not show asymmetric lipid distribution. We discuss possible mechanisms for the generation and relaxation of lipid asymmetry, as well as implications for studies using electroformed vesicles. The observed effects allow to control the molecular assembly of lipid bilayer leaflets. Vesicle tubulation as reported here is an example of protein-free reshaping of membranes and is caused by compositional lipid asymmetry between leaflets.
The atypical cyclin CNTD2 promotes colon cancer cell proliferation and migration
Authors: Sánchez-Botet Abril , Gasa Laura , Quandt Eva , Hernández-Ortega Sara , Jiménez Javier , Mezquita Pau , Carrasco-García Miquel Àngel , Kron Stephen J. , Vidal August , Villanueva Alberto , Ribeiro Mariana P. C. , Clotet Josep 
Published: August 2018

AbstractColorectal cancer (CRC) is one of the most common cancers worldwide, with 8–10% of these tumours presenting a BRAF (V600E) mutation. Cyclins are known oncogenes deregulated in many cancers, but the role of the new subfamily of atypical cyclins remains elusive. Here we have performed a systematic analysis of the protein expression levels of eight atypical cyclins in human CRC tumours and several cell lines, and found that CNTD2 is significantly upregulated in CRC tissue compared to the adjacent normal one. CNTD2 overexpression in CRC cell lines increases their proliferation capacity and migration, as well as spheroid formation capacity and anchorage-independent growth. Moreover, CNTD2 increases tumour growth in vivo on xenograft models of CRC with wild-type BRAF. Accordingly, CNTD2 downregulation significantly diminished the proliferation of wild-type BRAF CRC cells, suggesting that CNTD2 may represent a new prognostic factor and a promising drug target in the management of CRC.
Fat perception in the human frontal operculum, insular and somatosensory cortex
Authors: Wistehube Thomas , Rullmann Michael , Wiacek Claudia , Braun Peggy , Pleger Burkhard 
Published: August 2018

AbstractHere, we combined magnetic resonance imaging with lesion-symptom mapping in patients with chronic brain lesions to investigate brain representations of sugar and fat perception. Patients and healthy controls rated chocolate milkshakes that only differed in sugar or fat content. As compared to controls, patients showed an impaired fat, but not sugar perception. Impairments in fat perception overlapped with the anterior insula and frontal operculum, together assumed to underpin gustatory processing. We also identified the mid-dorsal insula as well as the primary and secondary somatosensory cortex - regions previously assumed to integrate oral-sensory inputs. These findings suggest that fat perception involves a specific set of brain regions that were previously reported to underpin gustatory processing and oral-sensory integration processes.
Spin-reorientation-induced magnetodielectric coupling effects in two layered perovskite magnets
Authors: Huang Bo , Zhang Jian-Yu , Huang Rui-Kang , Chen Ming-Kun , Xue Wei , Zhang Wei-Xiong , Zeng Ming-Hua , Chen Xiao-Ming 
Published: August 2018

Spin-reorientation-induced magnetodielectric effects were discovered in two layered perovskite magnets, (C6H5CH2CH2NH3)2[MCl4] (M = Mn2+ and Cu2+), via highly reproducible isothermal magnetodielectric measurements on single-crystal samples.
Accelerated adaptive super twisting sliding mode observer‐based drive shaft torque estimation for electric vehicle with automated manual transmission
Authors: Lin Cheng , Sun Shengxiong , Yi Jiang , Walker Paul , Zhang Nong 
Published: August 2018

The suddenly released torque that accumulated in the elastic drive shaft will bring torsional vibration and jerking feel at the shifting moment. A novel sliding mode observer is proposed to estimate the torque in drive shaft for a motor‐transmission integrated powertrain system. Non‐linear external characteristics of a driving motor and non‐linear drag torque are considered in the electric powertrain system. In order to attenuate the chatting problem, the second‐order super twisting sliding mode algorithm with an adaptive gain is adopted. Furthermore, a term ‘system damping’ is introduced to accelerate the estimation error convergence. The proposed estimation algorithm is tested on test rig for typical operating conditions. The results show that the torque in drive shaft can be estimated satisfactorily and the tracking error converges to 0 in a short time.
Low‐cost triboelectric sensor for speed measurement and weight estimation of vehicles
Authors: Yadav Deepshikha , Azad Puneet 
Published: August 2018

This study presents and tests the accuracy of a low‐cost triboelectric sensor for speed measurement and weight estimation of passenger vehicles in motion. Polytetrafluoroethylene and aluminium films are employed as sensing elements for generating voltage pulses due to movement of vehicles in real time. A number of road tests by 880 and 1020 kg cars in the speed range from 10 to 60 kmph show that the sensor is effective for measuring speeds with more than 95% accuracy and 3% mean absolute percentage error. For weight estimation, it is found that the voltage signals obtained from sensor due to impact between the tires of the vehicles and sensor varies linearly with speed ensuring the reliability of the sensor. On road experimental results reveal that the weight can be predicted from voltage signals by maintaining a database of different class of vehicles. The results and the overall concept indicate that the triboelectric sensor and associated wireless setup is promising for smart traffic‐monitoring applications at a very low cost.
A new dynamically self-consistent version of the Besançon Galaxy model
Authors: Bienaymé O. , Leca J. , Robin A. C. 
Published: August 2018

Context. Dynamically self-consistent galactic models are necessary for analysing and interpreting star counts, stellar density distributions, and stellar kinematics in order to understand the formation and the evolution of our Galaxy.
Aims. We modify and improve the dynamical self-consistency of the Besançon Galaxy model in the case of a stationary and axisymmetric gravitational potential.
Methods. Each stellar orbit is modelled by determining a Stäckel approximate integral of motion. Generalised Shu distribution functions (DFs) with three integrals of motion are used to model the stellar distribution functions.
Results. This new version of the Besançon model is compared with the previous axisymmetric BGM2014 version and we find that the two versions have similar densities for each stellar component. The dynamically self-consistency is improved and can be tested by recovering the forces and the potential through the Jeans equations applied to each stellar distribution function. Forces are recovered with an accuracy better than one per cent over most of the volume of the Galaxy.
Constraints on primordial black hole dark matter from Galactic center X-ray observations
Authors: Hektor Andi , Hütsi Gert , Raidal Martti 
Published: August 2018

Context. Surprisingly high masses of the black holes inferred from the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo gravitational wave measurements have lead to speculations that the observed mergers might be due to 𝒪(10) M⊙ primordial black holes (PBHs). Furthermore, it has been suggested that the whole amount of dark matter (DM) might be in that exotic form.
Aims. We investigate constraints on the PBH DM using NuSTAR Galactic center (GC) X-ray data.
Methods. We used a robust Monte Carlo approach in conjunction with a radiatively inefficient PBH accretion model with commonly accepted model parameters. Compared to previous studies we allowed for multiple forms of DM density profiles. Most importantly, our study includes treatment of the gas turbulence, which significantly modifies the relative velocity between PBHs and gas.
Results. We show that inclusion of the effects of gas turbulence and the uncertainties related to the DM density profile reduces significantly the gas accretion onto PBHs compared to the claimed values in previous papers. It is highly improbable to obtain accreting PBHs brighter than the NuSTAR point source limit using observationally determined gas velocities.
Conclusions. One can safely conclude that GC X-ray observations cannot rule out 𝒪(10) M⊙ PBH DM.
S’inspirer du rein pour filtrer l’eau, ou comment réinventer la passoire
Authors: Marbach Sophie 
Published: August 2018

Fournir de l’eau potable à tous et à moindre prix est un défiauquel fait face l’humanité. Les techniques actuelles pour dessaler l’eau de mer reposent sur le principe de la « passoire » pour séparer le sel et les déchets de l’eau, mais cette approche connaît plusieurs limites.
Nous nous sommes alors inspirés du rein humain, qui filtre l’urée de l’eau d’une façon radicalement différente : le secret réside dans sa géométrie en U qui sert d’échangeur salin. Après une preuve de concept, nous développons actuellement des systèmes inspirés du rein humain pour filtrer l’eau.
Stephen Hawking, étudiant à Cambridge
Authors: Vilain Christiane 
Published: August 2018

En interrogeant Brandon Carter, j’espère échapper à l’image standard du « génie-grand-malade », véhiculée par les médias après le décès de Stephen Hawking en mars 2018, et même bien avant, depuis la publication de son livre intitulé Une brève histoire du temps, en 1988.
Carter a fait ses études universitaires au Pembroke College de Cambridge. Après son travail de thèse et en postdoc dont il est question dans le texte qui suit, il est venu vivre en France pour raisons personnelles ; il a alors intégré le GAR (Groupe d’Astrophysique Relativiste) récemment créé à l’Observatoire de Meudon, et a beaucoup contribué au développement de ce groupe devenu ensuite le DARC, intégré aujourd’hui au LUTH du même établissement. Carter y est aujourd’hui Directeur de recherche émérite.
Endoscopic submucosal dissection of malignant non-pedunculated colorectal lesions
Authors: Rönnow Carl-Fredrik , Elebro Jacob , Toth Ervin , Thorlacius Henrik 
Published: August 2018

Abstract
Background and study aims Endoscopic submucosal dissection (ESD) is an established method for en bloc resection of large non-pedunculated colorectal lesions in Asia but dissemination of ESD in Western countries is limited. The aim of this study was to evaluate the role of ESD in the management of malignant non-pedunculated colorectal lesions in a European center.
Patients and methods Among 255 patients undergoing colorectal ESD between 2014 and 2016, 29 cases were identified as submucosal invasive cancers and included in this study. The main outcomes were en bloc, R0 and curative resection as well as procedural time, complications and recurrence.
Results Median tumor size was 40 mm (range 20 – 70 mm). Thirteen cancers were located in the colon and 16 were located in the rectum. Procedural time was 89 minutes (range 18 – 594 minutes). Complete resection was achieved in 28 cases, en bloc and R0 resection rates were 83 % and 69 %, respectively. Curative resection rate was 38 %. One case had a perforation in the sigmoid colon requiring emergency surgery. No significant bleeding occurred. Six patients underwent additional surgery after ESD, one of whom had residual tumor. One recurrence was detected in 20 patients that were followed-up endoscopically, median follow-up time was 13 months (range 2 – 30 months).
Conclusion ESD seems to be a safe and effective method for treating non-pedunculated malignant colorectal lesions after careful patient selection and proper endoscopic training.
Faster colonoscope withdrawal time without impaired detection using EndoRings
Authors: Thygesen John C. , Ponugoti Prasanna , Tippins William W. , Garcia Jonathan R. , Sullivan Andrew W. , Broadley Heather M. , Rex Douglas K. 
Published: August 2018

Abstract
Background and study aims Mucosal exposure devices on the colonoscope tip have improved detection. We evaluated detection and procedure times in colonoscopies performed with EndoRings.
Patients and methods We had 14 endoscopists in a university practice trial EndoRings. We compared detection and procedure times to age- and indication-matched procedures by the same endoscopists.
Results There were 137 procedures with EndoRings. The adenoma detection rate was 44 % with EndoRings vs. 39 % without (P = 0.39). Mean adenomas per colonoscopy (standard deviation) was 1.2 (2.3) with EndoRings vs. 0.9 (1.6) without (P = 0.055). Mean insertion time with EndoRings was 6.2 (3.2) minutes vs. 6.6 (6.7) minutes without (P = 0.81). Mean withdrawal time with EndoRings in all patients with or without polypectomy was 12.2 (5.3) minutes and 16.1 (10.3) minutes without (P = 0.0005).
Conclusion EndoRings may allow faster withdrawal during colonoscopy without any reduction in detection. Prospective trials with mucosal exposure devices targeting procedure times as primary endpoints are warranted.