bluuebunny/crossref_metadata_2025_split huggingface dataset:
The multicellularity genes of dictyostelid social amoebas
Authors: Glöckner Gernot , Lawal Hajara M. , Felder Marius , Singh Reema , Singer Gail , Weijer Cornelis J. , Schaap Pauline 
Published: June 2016

AbstractThe evolution of multicellularity enabled specialization of cells, but required novel signalling mechanisms for regulating cell differentiation. Early multicellular organisms are mostly extinct and the origins of these mechanisms are unknown. Here using comparative genome and transcriptome analysis across eight uni- and multicellular amoebozoan genomes, we find that 80% of proteins essential for the development of multicellular Dictyostelia are already present in their unicellular relatives. This set is enriched in cytosolic and nuclear proteins, and protein kinases. The remaining 20%, unique to Dictyostelia, mostly consists of extracellularly exposed and secreted proteins, with roles in sensing and recognition, while several genes for synthesis of signals that induce cell-type specialization were acquired by lateral gene transfer. Across Dictyostelia, changes in gene expression correspond more strongly with phenotypic innovation than changes in protein functional domains. We conclude that the transition to multicellularity required novel signals and sensors rather than novel signal processing mechanisms.
Notch-independent RBPJ controls angiogenesis in the adult heart
Authors: Díaz-Trelles Ramón , Scimia Maria Cecilia , Bushway Paul , Tran Danh , Monosov Anna , Monosov Edward , Peterson Kirk , Rentschler Stacey , Cabrales Pedro , Ruiz-Lozano Pilar , Mercola Mark 
Published: June 2016

AbstractIncreasing angiogenesis has long been considered a therapeutic target for improving heart function after injury such as acute myocardial infarction. However, gene, protein and cell therapies to increase microvascularization have not been successful, most likely because the studies failed to achieve regulated and concerted expression of pro-angiogenic and angiostatic factors needed to produce functional microvasculature. Here, we report that the transcription factor RBPJ is a homoeostatic repressor of multiple pro-angiogenic and angiostatic factor genes in cardiomyocytes. RBPJ controls angiogenic factor gene expression independently of Notch by antagonizing the activity of hypoxia-inducible factors (HIFs). In contrast to previous strategies, the cardiomyocyte-specific deletion ofRbpjincreased microvascularization of the heart without adversely affecting cardiac structure or function even into old age. Furthermore, the loss of RBPJ in cardiomyocytes increased hypoxia tolerance, improved heart function and decreased pathological remodelling after myocardial infarction, suggesting that inhibiting RBPJ might be therapeutic for ischaemic injury.
Pironetin reacts covalently with cysteine-316 of α-tubulin to destabilize microtubule
Authors: Yang Jianhong , Wang Yuxi , Wang Taijing , Jiang Jian , Botting Catherine H. , Liu Huanting , Chen Qiang , Yang Jinliang , Naismith James H. , Zhu Xiaofeng , Chen Lijuan 
Published: June 2016

AbstractMolecules that alter the normal dynamics of microtubule assembly and disassembly include many anticancer drugs in clinical use. So far all such therapeutics target β-tubulin, and structural biology has explained the basis of their action and permitted design of new drugs. However, by shifting the profile of β-tubulin isoforms, cancer cells become resistant to treatment. Compounds that bind to α-tubulin are less well characterized and unexploited. The natural product pironetin is known to bind to α-tubulin and is a potent inhibitor of microtubule polymerization. Previous reports had identified that pironetin reacts with lysine-352 residue however analogues designed on this model had much lower potency, which was difficult to explain, hindering further development. We report crystallographic and mass spectrometric data that reveal that pironetin forms a covalent bond to cysteine-316 in α-tubulin via a Michael addition reaction. These data provide a basis for the rational design of α-tubulin targeting chemotherapeutics.
Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues
Authors: Tzoumas Stratis , Nunes Antonio , Olefir Ivan , Stangl Stefan , Symvoulidis Panagiotis , Glasl Sarah , Bayer Christine , Multhoff Gabriele , Ntziachristos Vasilis 
Published: June 2016

AbstractLight propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation, an effect that causes spectral corruption. Spectral corruption has limited the quantification accuracy of optical and optoacoustic spectroscopic methods, and impeded the goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical goal for the assessment of oxygenation in physiological processes and disease. Here we describe light fluence in the spectral domain and introduce eigenspectra multispectral optoacoustic tomography (eMSOT) to account for wavelength-dependent light attenuation, and estimate blood sO2 within deep tissue. We validate eMSOT in simulations, phantoms and animal measurements and spatially resolve sO2 in muscle and tumours, validating our measurements with histology data. eMSOT shows substantial sO2 accuracy enhancement over previous optoacoustic methods, potentially serving as a valuable tool for imaging tissue pathophysiology.
Highly selective plasma-activated copper catalysts for carbon dioxide reduction to ethylene
Authors: Mistry Hemma , Varela Ana Sofia , Bonifacio Cecile S. , Zegkinoglou Ioannis , Sinev Ilya , Choi Yong-Wook , Kisslinger Kim , Stach Eric A. , Yang Judith C. , Strasser Peter , Cuenya Beatriz Roldan 
Published: June 2016

AbstractThere is an urgent need to develop technologies that use renewable energy to convert waste products such as carbon dioxide into hydrocarbon fuels. Carbon dioxide can be electrochemically reduced to hydrocarbons over copper catalysts, although higher efficiency is required. We have developed oxidized copper catalysts displaying lower overpotentials for carbon dioxide electroreduction and record selectivity towards ethylene (60%) through facile and tunable plasma treatments. Herein we provide insight into the improved performance of these catalysts by combining electrochemical measurements with microscopic and spectroscopic characterization techniques. Operando X-ray absorption spectroscopy and cross-sectional scanning transmission electron microscopy show that copper oxides are surprisingly resistant to reduction and copper+ species remain on the surface during the reaction. Our results demonstrate that the roughness of oxide-derived copper catalysts plays only a partial role in determining the catalytic performance, while the presence of copper+ is key for lowering the onset potential and enhancing ethylene selectivity.
A self-sustaining atomic magnetometer with τ−1 averaging property
Authors: Xu C. , Wang S. G. , Feng Y. Y. , Zhao L. , Wang L. J. 
Published: June 2016

AbstractQuantum measurement using coherent superposition of intrinsic atomic states has the advantage of being absolute measurement and can form metrological standards. One example is the absolute measurement of magnetic field by monitoring the Larmor precession of atomic spins whilst another being the Ramsey type atomic clock. Yet, in almost all coherent quantum measurement, the precision is limited by the coherence time beyond which, the uncertainty decreases only as τ−1/2. Here we show that by non-destructively measuring the phase of the Larmor precession and regenerating the coherence via optical pumping, the self-sustaining Larmor precession signal can persist indefinitely. Consequently, the precision of the magnetometer increases with time following a much faster τ−1 rule. A mean sensitivity of 240 "Equation missing" from 1 Hz to 10 Hz is realized, being close to the shot noise level. This method of coherence regeneration may also find important applications in improving the performance of atomic clocks.
Mutation of DNA Polymerase β R137Q Results in Retarded Embryo Development Due to Impaired DNA Base Excision Repair in Mice
Authors: Pan Feiyan , Zhao Jing , Zhou Ting , Kuang Zhihui , Dai Huifang , Wu Huan , Sun Hongfang , Zhou Xiaolong , Wu Xuping , Hu Zhigang , He Lingfeng , Shen Binghui , Guo Zhigang 
Published: June 2016

AbstractDNA polymerase β (Pol β), a key enzyme in the DNA base excision repair (BER) pathway, is pivotal in maintaining the integrity and stability of genomes. One Pol β mutation that has been identified in tumors, R137Q (arginine to glutamine substitution), has been shown to lower polymerase activity and impair its DNA repair capacity. However, the exact functional deficiency associated with this polymorphism in living organisms is still unknown. Here, we constructed Pol β R137Q knock-in mice and found that homozygous knock-in mouse embryos were typically small in size and had a high mortality rate (21%). These embryonic abnormalities were caused by slow cell proliferation and increased apoptosis. In R137Q knock-in mouse embryos, the BER efficiency was severely impaired, which subsequently resulted in double-strand breaks (DSBs) and chromosomal aberrations. Furthermore, R137Q mouse embryo fibroblasts (MEFs) were more sensitive to DNA-damaging reagents, such as methyl methanesulfonate (MMS) and H2O2. They displayed a higher percentage of DSBs and were more likely to undergo apoptosis. Our results indicate that R137 is a key amino acid site that is essential for proper Pol β functioning in maintaining genomic stability and embryo development.
Growth of Co2FeAl Heusler alloy thin films on Si(100) having very small Gilbert damping by Ion beam sputtering
Authors: Husain Sajid , Akansel Serkan , Kumar Ankit , Svedlindh Peter , Chaudhary Sujeet 
Published: June 2016

AbstractThe influence of growth temperatureTs(300–773 K) on the structural phase ordering, static and dynamic magnetization behaviour has been investigated in ion beam sputtered full Heusler alloy Co2FeAl (CFA) thin films on industrially important Si(100) substrate. TheB2type magnetic ordering is established in these films based on the clear observation of the (200) diffraction peak. These ion beam sputtered CFA films possess very small surface roughness of the order of subatomic dimensions (<3 Å) as determined from the fitting of XRR spectra and also by AFM imaging. This is supported by the occurrence of distinct Kiessig fringes spanning over the whole scanning range (~4°) in the x-ray reflectivity (XRR) spectra. The Gilbert damping constant α and effective magnetization4πMeffare found to vary from 0.0053 ± 0.0002 to 0.0015 ± 0.0001 and 13.45 ± 00.03 kG to 14.03 ± 0.04 kG, respectively. These Co2FeAl films possess saturation magnetization ranging from 4.82 ± 0.09 to 5.22 ± 0.10 μB/f.u. consistent with the bulkL21-type ordering. A record low α-value of 0.0015 is obtained for Co2FeAl films deposited on Si substrate atTs ~ 573 K.
A high-resolution palaeoenvironmental record from carbonate deposits in the Roman aqueduct of Patara, SW Turkey, from the time of Nero
Authors: Passchier Cornelis , Sürmelihindi Gül , Spötl Christoph 
Published: June 2016

AbstractAn inscription on the supporting wall of the inverted siphon of the aqueduct of the ancient Roman city of Patara, SW Turkey, explains how the wall collapsed during an earthquake and was subsequently restored. Carbonate deposits formed inside the aqueduct channel show cyclic stable isotope changes representing 17 years of deposition. This sequence, together with the text of the inscription, allows dating the earthquake to 68 AD and the original inauguration of the aqueduct to the winter of 51/52 AD. Thus, the carbonate deposits represent a high-resolution record of palaeotemperature and precipitation for SW Turkey covering the complete reign of the Emperor Nero. The period shows a cooling and drying trend after an initial warm and more humid period, interrupted by a few anomalous years. These 2 cm of calcite highlight the significance of carbonate deposits in ancient water supply systems as a high-resolution archive for palaeoclimate, palaeoseismology and archaeology.
Spatially oriented plasmonic ‘nanograter’ structures
Authors: Liu Zhe , Cui Ajuan , Gong Zhijie , Li Hongqiang , Xia Xiaoxiang , Shen Tiehan H. , Li Junjie , Yang Haifang , Li Wuxia , Gu Changzhi 
Published: June 2016

AbstractOne of the key motivations in producing 3D structures has always been the realization of metamaterials with effective constituent properties that can be tuned in all propagation directions at various frequencies. Here, we report the investigation of spatially oriented “Nanograter” structures with orientation-dependent responses over a wide spectrum by focused-ion-beam based patterning and folding of thin film nanostructures. Au nano units of different shapes, standing along specifically designated orientations, were fabricated. Experimental measurements and simulation results show that such structures offer an additional degree of freedom for adjusting optical properties with the angle of inclination, in additional to the size of the structures. The response frequency can be varied in a wide range (8 μm–14 μm) by the spatial orientation (0°–180°) of the structures, transforming the response from magnetic into electric coupling. This may open up prospects for the fabrication of 3D nanostructures as optical interconnects, focusing elements and logic elements, moving toward the realization of 3D optical circuits.
One Step Quantum Key Distribution Based on EPR Entanglement
Authors: Li Jian , Li Na , Li Lei-Lei , Wang Tao 
Published: June 2016

AbstractA novel quantum key distribution protocol is presented, based on entanglement and dense coding and allowing asymptotically secure key distribution. Considering the storage time limit of quantum bits, a grouping quantum key distribution protocol is proposed, which overcomes the vulnerability of first protocol and improves the maneuverability. Moreover, a security analysis is given and a simple type of eavesdropper’s attack would introduce at least an error rate of 46.875%. Compared with the “Ping-pong” protocol involving two steps, the proposed protocol does not need to store the qubit and only involves one step.
Responsive Guest Encapsulation of Dynamic Conjugated Microporous Polymers
Authors: Xu Lai , Li Youyong 
Published: June 2016

AbstractThe host-guest complexes of conjugated microporous polymers encapsulating C60 and dye molecules have been investigated systematically. The orientation of guest molecules inside the cavities, have different terms: inside the open cavities of the polymer, or inside the cavities formed by packing different polymers. The host backbone shows responsive dynamic behavior in order to accommodate the size and shape of incoming guest molecule or guest aggregates. Simulations show that the host-guest binding of conjugated polymers is stronger than that of non-conjugated polymers. This detailed study could provide a clear picture for the host-guest interaction for dynamic conjugated microporous polymers. The mechanism obtained could guide designing new conjugated microporous polymers.
Impact of dietary resistant starch type 4 on human gut microbiota and immunometabolic functions
Authors: Upadhyaya Bijaya , McCormack Lacey , Fardin-Kia Ali Reza , Juenemann Robert , Nichenametla Sailendra , Clapper Jeffrey , Specker Bonny , Dey Moul 
Published: June 2016

AbstractDietary modulation of the gut microbiota impacts human health. Here we investigated the hitherto unknown effects of resistant starch type 4 (RS4) enriched diet on gut microbiota composition and short-chain fatty acid (SCFA) concentrations in parallel with host immunometabolic functions in twenty individuals with signs of metabolic syndrome (MetS). Cholesterols, fasting glucose, glycosylated haemoglobin and proinflammatory markers in the blood as well as waist circumference and % body fat were lower post intervention in the RS4 group compared with the control group. 16S-rRNA gene sequencing revealed a differential abundance of 71 bacterial operational taxonomic units, including the enrichment of three Bacteroides species and one each of Parabacteroides, Oscillospira, Blautia, Ruminococcus, Eubacterium and Christensenella species in the RS4 group. Gas chromatography–mass spectrometry revealed higher faecal SCFAs, including butyrate, propionate, valerate, isovalerate and hexanoate after RS4-intake. Bivariate analyses showed RS4-specific associations of the gut microbiota with the host metabolic functions and SCFA levels. Here we show that dietary RS4 induced changes in the gut microbiota are linked to its biological activity in individuals with signs of MetS. These findings have potential implications for dietary guidelines in metabolic health management.
Quantifying cadherin mechanotransduction machinery assembly/disassembly dynamics using fluorescence covariance analysis
Authors: Vedula Pavan , Cruz Lissette A. , Gutierrez Natasha , Davis Justin , Ayee Brian , Abramczyk Rachel , Rodriguez Alexis J. 
Published: June 2016

AbstractQuantifying multi-molecular complex assembly in specific cytoplasmic compartments is crucial to understand how cells use assembly/disassembly of these complexes to control function. Currently, biophysical methods like Fluorescence Resonance Energy Transfer and Fluorescence Correlation Spectroscopy provide quantitative measurements of direct protein-protein interactions, while traditional biochemical approaches such as sub-cellular fractionation and immunoprecipitation remain the main approaches used to study multi-protein complex assembly/disassembly dynamics. In this article, we validate and quantify multi-protein adherens junction complex assembly in situ using light microscopy and Fluorescence Covariance Analysis. Utilizing specific fluorescently-labeled protein pairs, we quantified various stages of adherens junction complex assembly, the multiprotein complex regulating epithelial tissue structure and function following de novo cell-cell contact. We demonstrate: minimal cadherin-catenin complex assembly in the perinuclear cytoplasm and subsequent localization to the cell-cell contact zone, assembly of adherens junction complexes, acto-myosin tension-mediated anchoring and adherens junction maturation following de novo cell-cell contact. Finally applying Fluorescence Covariance Analysis in live cells expressing fluorescently tagged adherens junction complex proteins, we also quantified adherens junction complex assembly dynamics during epithelial monolayer formation.
Microfluidics-based side view flow chamber reveals tether-to-sling transition in rolling neutrophils
Authors: Marki Alex , Gutierrez Edgar , Mikulski Zbigniew , Groisman Alex , Ley Klaus 
Published: June 2016

AbstractNeutrophils rolling at high shear stress (above 6 dyn/cm2) form tethers in the rear and slings in the front. Here, we developed a novel photo-lithographically fabricated, silicone(PDMS)-based side-view flow chamber to dynamically visualize tether and sling formation. Fluorescently membrane-labeled mouse neutrophils rolled on P-selectin substrate at 10 dyn/cm2. Most rolling cells formed 5 tethers that were 2–30 μm long. Breaking of a single tether caused a reproducible forward microjump of the cell, showing that the tether was load-bearing. About 15% of all tether-breaking events resulted in slings. The tether-to-sling transition was fast (<100 ms) with no visible material extending above the rolling cell, suggesting a very low bending modulus of the tether. The sling downstream of the rolling cell aligned according to the streamlines before landing on the flow chamber. These new observations explain how slings form from tethers and provide insight into their biomechanical properties.
Temporal Lobe Epilepsy Alters Auditory-motor Integration For Voice Control
Authors: Li Weifeng , Chen Ziyi , Yan Nan , Jones Jeffery A. , Guo Zhiqiang , Huang Xiyan , Chen Shaozhen , Liu Peng , Liu Hanjun 
Published: June 2016

AbstractTemporal lobe epilepsy (TLE) is the most common drug-refractory focal epilepsy in adults. Previous research has shown that patients with TLE exhibit decreased performance in listening to speech sounds and deficits in the cortical processing of auditory information. Whether TLE compromises auditory-motor integration for voice control, however, remains largely unknown. To address this question, event-related potentials (ERPs) and vocal responses to vocal pitch errors (1/2 or 2 semitones upward) heard in auditory feedback were compared across 28 patients with TLE and 28 healthy controls. Patients with TLE produced significantly larger vocal responses but smaller P2 responses than healthy controls. Moreover, patients with TLE exhibited a positive correlation between vocal response magnitude and baseline voice variability and a negative correlation between P2 amplitude and disease duration. Graphical network analyses revealed a disrupted neuronal network for patients with TLE with a significant increase of clustering coefficients and path lengths as compared to healthy controls. These findings provide strong evidence that TLE is associated with an atypical integration of the auditory and motor systems for vocal pitch regulation and that the functional networks that support the auditory-motor processing of pitch feedback errors differ between patients with TLE and healthy controls.
Multiple cone pathways are involved in photic regulation of retinal dopamine
Authors: Qiao Sheng-Nan , Zhang Zhijing , Ribelayga Christophe P. , Zhong Yong-Mei , Zhang Dao-Qi 
Published: June 2016

AbstractDopamine is a key neurotransmitter in the retina and plays a central role in the light adaptive processes of the visual system. The sole source of retinal dopamine is dopaminergic amacrine cells (DACs). We and others have previously demonstrated that DACs are activated by rods, cones and intrinsically photosensitive retinal ganglion cells (ipRGCs) upon illumination. However, it is still not clear how each class of photosensitive cells generates light responses in DACs. We genetically isolated cone function in mice to specifically examine the cone-mediated responses of DACs and their neural pathways. In addition to the reported excitatory input to DACs from light-increment (ON) bipolar cells, we found that cones alternatively signal to DACs via a retrograde signalling pathway from ipRGCs. Cones also produce ON and light-decrement (OFF) inhibitory responses in DACs, which are mediated by other amacrine cells, likely driven by type 1 and type 2/3a OFF bipolar cells, respectively. Dye injections indicated that DACs had similar morphological profiles with or without ON/OFF inhibition. Our data demonstrate that cones utilize specific parallel excitatory and inhibitory circuits to modulate DAC activity and efficiently regulate dopamine release and the light-adaptive state of the retina.