bluuebunny/crossref_metadata_2025_split huggingface dataset:
Separation of Ketorolac enantiomers on polysaccharide‐based chiral stationary phases using a polar organic mobile phase
Authors: He Yunchao , Wu Yaling , Cheng Lingping , He Shanshan , Wang Qiuhua , Wang Huiying , Ke Yanxiong 
Published: June 2018

AbstractKetorolac has been widely applied in clinical medicine for its antipyretic, analgesic and anti‐inflammatory pharmacological activity. Research showed that the analgesic effect of the S enantiomer is 230 times stronger than that of the R enantiomer. Getting the high‐purity S enantiomer of Ketorolac has profound significance but still remains a challenging topic. In this work, the separation of the R and S enantiomers of Ketorolac was investigated on polysaccharide‐based chiral stationary phases. Chiralcel AD‐H, OD‐H, OJ‐H and AS‐H columns were evaluated using polar organic and normal phase mode, respectively, in which the OJ‐H column showed the best performance with high selectivity and resolution for Ketorolac with α = 2.43 and RS = 9.04 by using methanol/formic acid (100:0.1, v/v) as the mobile phase. The influences of acid additive, composition of mobile phase and temperature were examined. The coating amount of cellulose tris‐(4‐methylbenzoate) has significant influence on the sample loadability. The high loadability of chiral stationary phases coated with 40% of cellulose tris‐(4‐methylbenzoate) allows preparative separation up to 16 mg on an analytical column of 250 × 4.6 mm id in a single run for Ketoroac using methanol/formic acid (100:0.1, v/v) as mobile phase, which shows a potential application in industrial preparation.
Characterization of ten extreme disturbance events in the context of social and ecological systems
Authors: Lugo Ariel E. 
Published: June 2018

AbstractAn extreme disturbance event is one in which any of its component disturbance forces and their interactions with affected systems have dimensions and responses that exceed the known range of variation expected of those parameters. If the exposed system does not respond or exhibits a low level response to an event, the event was not extreme to the exposed system, regardless of the dimensions of its disturbance forces. Extreme disturbance events are complex and require disaggregation to improve understanding of their effects. The areas affected by extreme events and the duration of the events are related but involve many orders of magnitude in terms of area affected and duration. One way to compare events is through a common and objective unit of measure such as energy. A comparison of ten extreme events in terms of their power and total energy delivered per unit area revealed a broad range of values among them. The power of events ranged 8 orders of magnitude and the total load per unit area ranged 14 orders of magnitude. Each event had different points of interaction with exposed ecosystems. When exposed to the same extreme event, the response of social systems is different from the response of the ecological systems. Also, social systems recovered quicker to a category 3 hurricane than did ecological systems. Both social and ecological systems have the capacity to evolve, adapt, innovate, and develop novelty in response to the selective pressure of extreme events.
Grain Boundary Serration in Nickel-Based Superalloy Inconel 600: Generation and Effects on Mechanical Behavior
Authors: Tang Yuanbo T. , Wilkinson Angus J. , Reed Roger C. 
Published: June 2018

Abstract
Grain boundary serration in the superalloy Inconel 600 was studied. Two microstructural variants, one with nonserrated and the other with serrated grain boundaries were generated by altering the heat-treatment conditions, while keeping other aspects of the microstructure unchanged. The effect on the creep response between 700 °C and 900 °C was measured, and the different failure modes and accumulated damage were quantified using high-angular resolution electron backscatter diffraction analysis in the scanning electron microscope and also by X-ray computed tomography. It is found that serration plays a more crucial role in the high-temperature/low-stress regime when an intergranular cracking mechanism involving cavitation is operative; here it plays a role in improving both creep life and creep ductility. Any effect of serration is less prevalent at low temperatures where transgranular failure is dominant.
Nonlinearity optimization of dissipative-soliton fiber laser for generation of pulses with 350 kW peak power
Authors: Chi Han , Liu Bowen , Song Youjian , Hu Minglie , Chai Lu , Shen Weidong , Liu Xu , Wang Chingyue 
Published: June 2018

We demonstrate a nonlinearity optimization method by altering distribution of passive fibers in a dissipative-soliton mode-locked fiber laser to level up output parameters. In the numerical simulation, we found that the passive fiber segment after gain fiber characterizes the highest average B-integral among fiber segments. By reducing the length of this fiber section and keeping the total passive fiber length as constant, the output pulse energy can be effectively scaled up while maintaining a short dechirped pulse duration, resulting in boosting peak power. With this method, 37-nJ pulses are generated from a dissipative-soliton mode-locked cladding pumped ytterbium-doped single-mode fiber laser in the experiment. The pulse can be dechirped to 66 fs with 350 kW peak power. Moreover, the pulse pedestal is suppressed by a vector-dispersion compressor.
A practice-based framework for understanding (informal) play as practice phenomena in organizations
Authors: Spraggon Martin , Bodolica Virginia 
Published: June 2018

AbstractPlay as practice literature has long been dominated by studies on the serious play. Focusing on a play that develops in artificial settings and requires managerial intervention, these studies overlook other playful manifestations, which are employee-driven and situated in the natural work habitat. This paper extends current play as practice reflections by adopting the notion of informal play as an alternative to prevailing views that espouses the employee rather than the managerial perspective. Drawing upon insights from play and practice literature, we incorporate five practice-based constructs into the systematic analysis of informal play in the world of work. We advance an integrative framework that highlights the constitutive relationships between the retained constructs and acknowledges different enactments of informal play for generating productive outcomes or cynically resisting authority. A multi-domain agenda for future inquiry that may contribute to a more nuanced understanding of informal play as practice in organizations concludes the paper.
Early mapping of industrial tomato in Central and Southern Italy with Sentinel 2, aerial and RapidEye additional data
Authors: Vaglio Laurin Gaia , Belli Claudio , Bianconi Roberto , Laranci Pietro , Papale Dario 
Published: June 2018

AbstractTimely crop information, i.e. well before harvesting time and at first stages of crop development, can benefit farmers and producer organizations. The current case study documents the procedure to deliver early data on planted tomato to users, showing the potential of Sentinel 2 (S2) to map tomato at the very beginning of the crop season, which is a challenging task. Using satellite data, integrated with ground and aerial data, an initial estimate of area planted with tomato and early tomato maps were generated in seven main production areas in Italy. Estimates of the amount of area planted with tomato provided similar results either when derived from field surveys or from remote-sensing-based classification. Tomato early maps showed a producer accuracy >80% in seven cases out of nine, and a user accuracy >80% in five cases out of nine, with differences attributed to the varying agricultural characteristics and environmental heterogeneity of the study areas. The additional use of aerial data improved producer accuracy moderately. The ability to identify abrupt growth changes, such as those caused by natural hazards, was also analysed: S2 detected significant changes in tomato growth between a hailstorm-affected area and a control area. The study suggests that S2, with enhanced spectral capabilities and open data policy, represents very valuable data, allowing crop monitoring at an early development stage.
Aeromagnetic Data Reveal Potential Seismogenic Basement Faults in the Induced Seismicity Setting of Oklahoma
Authors: Shah A. K. , Crain K. 
Published: June 2018

AbstractNew aeromagnetic survey data collected over north central Oklahoma image possible seismogenic faults in the crystalline basement. Linear earthquake sequences associated with induced seismicity suggest the reactivation of ancient basement faults, but few of these sequences are aligned with mapped faults. The new data show many earthquake sequences aligned with linear magnetic gradients or offsets between anomalies, while mapped faults, which mainly describe sedimentary cover, show limited correspondence with either. This strongly suggests significant structural differences between the crystalline basement and sedimentary cover. Furthermore, while the earthquakes are occurring on reactivated ancient faults, most of these faults have likely been inactive for millions of years. The magnetic data exhibit many gradient lineaments that are optimally oriented for fault slip, and the earthquake data suggest additional optimally oriented faults. Together these data suggest the presence of potentially numerous seismogenic faults throughout the region, which may contribute to high levels of induced seismicity.
Comparison of antibacterial activity of alexidine alone or as a final irrigant with sodium hypochlorite and chlorhexidine
Authors: da Silva Thaís M , Alves Flávio RF , Lutterbach Márcia TS , Paiva Maurício M , Ferreira Dennis de Carvalho 
Published: June 2018

Abstract
Aims:
To compare the antibacterial activity of alexidine (ALX) alone or as a final irrigant in combination with sodium hypochlorite (NaOCl), with the most common canal irrigants, NaOCl and chlorhexidine (CHX).

Materials and methods:
Ninety-four root fragments from extracted human teeth were infected with Enterococcus faecalis for 24 h and then distributed into 4 groups of 20 fragments each. The NaOCl, CHX and ALX groups were immersed in 1 ml of 2.5% NaOCl, 2% CHX, and 1% ALX for 10 min, respectively. The samples of the NaOCl+ALX group were immersed in 1 ml of 2.5% NaOCl for 10 min followed by 1% ALX for 10 min. Bacteriological samples were taken, cultured, and the colony-forming units were counted.

Results:
There was no significant differences among the experimental groups (P>0.05) except for the comparisons CHX versus ALX and NaOCl+ALX versus ALX (P=0.004). ALX alone was the worst irrigant. CHX and NaOCl+ALX eradicated all bacteria. All experimental groups were significantly more effective than the control group immersed in saline (P<0.05).

Conclusions:
The antibacterial effect of ALX alone was inferior to 2% CHX and 2.5% NaOCl. However, the combination of NaOCl with ALX as a final irrigant eradicated the biofilms.
Modular ssDNA binding and inhibition of telomerase activity by designer PPR proteins
Authors: Spåhr Henrik , Chia Tiongsun , Lingford James P. , Siira Stefan J. , Cohen Scott B. , Filipovska Aleksandra , Rackham Oliver 
Published: June 2018

AbstractDNA is typically found as a double helix, however it must be separated into single strands during all phases of DNA metabolism; including transcription, replication, recombination and repair. Although recent breakthroughs have enabled the design of modular RNA- and double-stranded DNA-binding proteins, there are currently no tools available to manipulate single-stranded DNA (ssDNA). Here we show that artificial pentatricopeptide repeat (PPR) proteins can be programmed for sequence-specific ssDNA binding. Interactions occur using the same code and specificity as for RNA binding. We solve the structures of DNA-bound and apo proteins revealing the basis for ssDNA binding and how hydrogen bond rearrangements enable the PPR structure to envelope its ssDNA target. Finally, we show that engineered PPRs can be designed to bind telomeric ssDNA and can block telomerase activity. The modular mode of ssDNA binding by PPR proteins provides tools to target ssDNA and to understand its importance in cells.
Chemical warfare between leafcutter ant symbionts and a co-evolved pathogen
Authors: Heine Daniel , Holmes Neil A. , Worsley Sarah F. , Santos Ana Carolina A. , Innocent Tabitha M. , Scherlach Kirstin , Patrick Elaine H. , Yu Douglas W. , Murrell J. Colin , Vieria Paulo C. , Boomsma Jacobus J. , Hertweck Christian , Hutchings Matthew I. , Wilkinson Barrie 
Published: June 2018

AbstractAcromyrmex leafcutter ants form a mutually beneficial symbiosis with the fungus Leucoagaricus gongylophorus and with Pseudonocardia bacteria. Both are vertically transmitted and actively maintained by the ants. The fungus garden is manured with freshly cut leaves and provides the sole food for the ant larvae, while Pseudonocardia cultures are reared on the ant-cuticle and make antifungal metabolites to help protect the cultivar against disease. If left unchecked, specialized parasitic Escovopsis fungi can overrun the fungus garden and lead to colony collapse. We report that Escovopsis upregulates the production of two specialized metabolites when it infects the cultivar. These compounds inhibit Pseudonocardia and one, shearinine D, also reduces worker behavioral defenses and is ultimately lethal when it accumulates in ant tissues. Our results are consistent with an active evolutionary arms race between Pseudonocardia and Escovopsis, which modifies both bacterial and behavioral defenses such that colony collapse is unavoidable once Escovopsis infections escalate.
Quantum limit transport and destruction of the Weyl nodes in TaAs
Authors: Ramshaw B. J. , Modic K. A. , Shekhter Arkady , Zhang Yi , Kim Eun-Ah , Moll Philip J. W. , Bachmann Maja D. , Chan M. K. , Betts J. B. , Balakirev F. , Migliori A. , Ghimire N. J. , Bauer E. D. , Ronning F. , McDonald R. D. 
Published: June 2018

AbstractWeyl fermions are a recently discovered ingredient for correlated states of electronic matter. A key difficulty has been that real materials also contain non-Weyl quasiparticles, and disentangling the experimental signatures has proven challenging. Here we use magnetic fields up to 95 T to drive the Weyl semimetal TaAs far into its quantum limit, where only the purely chiral 0th Landau levels of the Weyl fermions are occupied. We find the electrical resistivity to be nearly independent of magnetic field up to 50 T: unusual for conventional metals but consistent with the chiral anomaly for Weyl fermions. Above 50 T we observe a two-order-of-magnitude increase in resistivity, indicating that a gap opens in the chiral Landau levels. Above 80 T we observe strong ultrasonic attenuation below 2 K, suggesting a mesoscopically textured state of matter. These results point the way to inducing new correlated states of matter in the quantum limit of Weyl semimetals.
Nature of the metal-insulator transition in few-unit-cell-thick LaNiO3 films
Authors: Golalikhani M. , Lei Q. , Chandrasena R. U. , Kasaei L. , Park H. , Bai J. , Orgiani P. , Ciston J. , Sterbinsky G. E. , Arena D. A. , Shafer P. , Arenholz E. , Davidson B. A. , Millis A. J. , Gray A. X. , Xi X. X. 
Published: June 2018

AbstractThe nature of the metal-insulator transition in thin films and superlattices of LaNiO3 only a few unit cells in thickness remains elusive despite tremendous effort. Quantum confinement and epitaxial strain have been evoked as the mechanisms, although other factors such as growth-induced disorder, cation non-stoichiometry, oxygen vacancies, and substrate–film interface quality may also affect the observable properties of ultrathin films. Here we report results obtained for near-ideal LaNiO3 films with different thicknesses and terminations grown by atomic layer-by-layer laser molecular beam epitaxy on LaAlO3 substrates. We find that the room-temperature metallic behavior persists until the film thickness is reduced to an unprecedentedly small 1.5 unit cells (NiO2 termination). Electronic structure measurements using X-ray absorption spectroscopy and first-principles calculation suggest that oxygen vacancies existing in the films also contribute to the metal-insulator transition.
Molecular principles underlying dual RNA specificity in the Drosophila SNF protein
Authors: Weber Gert , DeKoster Gregory T. , Holton Nicole , Hall Kathleen B. , Wahl Markus C. 
Published: June 2018

AbstractThe first RNA recognition motif of the Drosophila SNF protein is an example of an RNA binding protein with multi-specificity. It binds different RNA hairpin loops in spliceosomal U1 or U2 small nuclear RNAs, and only in the latter case requires the auxiliary U2A′ protein. Here we investigate its functions by crystal structures of SNF alone and bound to U1 stem-loop II, U2A′ or U2 stem-loop IV and U2A′, SNF dynamics from NMR spectroscopy, and structure-guided mutagenesis in binding studies. We find that different loop-closing base pairs and a nucleotide exchange at the tips of the loops contribute to differential SNF affinity for the RNAs. U2A′ immobilizes SNF and RNA residues to restore U2 stem-loop IV binding affinity, while U1 stem-loop II binding does not require such adjustments. Our findings show how U2A′ can modulate RNA specificity of SNF without changing SNF conformation or relying on direct RNA contacts.
Alternative assembly of respiratory complex II connects energy stress to metabolic checkpoints
Authors: Bezawork-Geleta Ayenachew , Wen He , Dong LanFeng , Yan Bing , Vider Jelena , Boukalova Stepana , Krobova Linda , Vanova Katerina , Zobalova Renata , Sobol Margarita , Hozak Pavel , Novais Silvia Magalhaes , Caisova Veronika , Abaffy Pavel , Naraine Ravindra , Pang Ying , Zaw Thiri , Zhang Ping , Sindelka Radek , Kubista Mikael , Zuryn Steven , Molloy Mark P. , Berridge Michael V. , Pacak Karel , Rohlena Jakub , Park Sunghyouk , Neuzil Jiri 
Published: June 2018

AbstractCell growth and survival depend on a delicate balance between energy production and synthesis of metabolites. Here, we provide evidence that an alternative mitochondrial complex II (CII) assembly, designated as CIIlow, serves as a checkpoint for metabolite biosynthesis under bioenergetic stress, with cells suppressing their energy utilization by modulating DNA synthesis and cell cycle progression. Depletion of CIIlow leads to an imbalance in energy utilization and metabolite synthesis, as evidenced by recovery of the de novo pyrimidine pathway and unlocking cell cycle arrest from the S-phase. In vitro experiments are further corroborated by analysis of paraganglioma tissues from patients with sporadic, SDHA and SDHB mutations. These findings suggest that CIIlow is a core complex inside mitochondria that provides homeostatic control of cellular metabolism depending on the availability of energy.
Scanning nuclear resonance imaging of a hyperfine-coupled quantum Hall system
Authors: Hashimoto Katsushi , Tomimatsu Toru , Sato Ken , Hirayama Yoshiro 
Published: June 2018

AbstractNuclear resonance (NR) is widely used to detect and characterise nuclear spin polarisation and conduction electron spin polarisation coupled by a hyperfine interaction. While the macroscopic aspects of such hyperfine-coupled systems have been addressed in most relevant studies, the essential role of local variation in both types of spin polarisation has been indicated in 2D semiconductor systems. In this study, we apply a recently developed local and highly sensitive NR based on a scanning probe to a hyperfine-coupled quantum Hall (QH) system in a 2D electron gas subject to a strong magnetic field. We succeed in imaging the NR intensity and Knight shift, uncovering the spatial distribution of both the nuclear and electron spin polarisation. The results reveal the microscopic origin of the nonequilibrium QH phenomena, and highlight the potential use of our technique in microscopic studies on various electron spin systems as well as their correlations with nuclear spins.
Optogenetic auditory fMRI reveals the effects of visual cortical inputs on auditory midbrain response
Authors: Leong Alex T. L. , Dong Celia M. , Gao Patrick P. , Chan Russell W. , To Anthea , Sanes Dan H. , Wu Ed X. 
Published: June 2018

AbstractSensory cortices contain extensive descending (corticofugal) pathways, yet their impact on brainstem processing – particularly across sensory systems – remains poorly understood. In the auditory system, the inferior colliculus (IC) in the midbrain receives cross-modal inputs from the visual cortex (VC). However, the influences from VC on auditory midbrain processing are unclear. To investigate whether and how visual cortical inputs affect IC auditory responses, the present study combines auditory blood-oxygenation-level-dependent (BOLD) functional MRI (fMRI) with cell-type specific optogenetic manipulation of visual cortex. The results show that predominant optogenetic excitation of the excitatory pyramidal neurons in the infragranular layers of the primary VC enhances the noise-evoked BOLD fMRI responses within the IC. This finding reveals that inputs from VC influence and facilitate basic sound processing in the auditory midbrain. Such combined optogenetic and auditory fMRI approach can shed light on the large-scale modulatory effects of corticofugal pathways and guide detailed electrophysiological studies in the future.
Low night temperature at veraison enhances the accumulation of anthocyanins in Corvina grapes (Vitis Vinifera L.)
Authors: Gaiotti Federica , Pastore Chiara , Filippetti Ilaria , Lovat Lorenzo , Belfiore Nicola , Tomasi Diego 
Published: June 2018

AbstractClimate change is a major concern in grape production worldwide. Nights have been warming much faster than the days, raising attention on the effect of night temperatures on grape and wine composition. In this study we evaluated the effect of night temperatures on grape coloration in the cv. Corvina (Vitis viniferaL.). In 2015 and 2016 potted plants were cooled overnight (10–11 °C) during two berry ripening phases, veraison (TV) or post-veraison (TPV), and compared to control vines (C) grown at ambient night temperature (15–20 °C on average). Cooling treatment around veraison (TV) hastened berry anthocyanin accumulation, while the same treatment applied after veraison (TPV) was ineffective. Molecular analysis revealed an increased transcription of four key genes in anthocyanin biosynthesis (CHS3, F3H1, MYBA1 and UFGT) in TV treatment. These results suggest that the anthocyanin biosynthesis capacity was enhanced by cool nights during veraison. However, since the gene expression was not always temporally correlated to the increase in anthocyanin concentration, we speculate on the presence of mechanisms, such as enzymatic regulation or anthocyanin transport, which may contribute in determining the anthocyanin accumulation under low night temperatures.