bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Model Experiment of Fracture Induced Long‐Period Events: Injection of Pressurized Gas Into a Viscoelastic Rock Analog
Authors: Namiki Atsuko , Takahashi Makoto , Tsutsui Ryo 
Published: October 2019

AbstractLow‐frequency events observed in volcanic areas preceding phreatic or phreatomagmatic eruptions may be excited by the injection of pressurized gas into damaged/heated rocks or solidifying magmas. To simulate this process, we conducted a series of gas injection experiments in gels as an analog of such soft rocks. When we inject the pressurized air into a quasi‐Maxwell fluid with higher and lower shear moduli, cracks or a slug appears, respectively. The crack propagation velocity consists of the shear wave velocity of the gel. At the beginning of the crack generation, multiple cracks emerge, causing pulse‐like low‐frequency signals. In contrast, the slug grows faster than the shear wave velocity and excites high‐frequency oscillation. These results show the possibility that the low‐frequency seismicity observed in volcanic regions is the result of not only the resonance of a crack but also the crack propagation in soft rocks.
Impacts of Lithologically Controlled Mechanisms on Downstream Bedrock Valley Widening
Authors: Langston Abigail L. , Temme Arnaud J. A. M. 
Published: October 2019

AbstractWide, fluvially carved bedrock valleys are found around the world, but little is known about the processes and mechanisms controlling their formation. We know that rates of valley widening are controlled by stream discharge and bedrock lithology, with larger streams and softer rocks resulting in wider valleys. But lithology also controls widening mechanisms that cause valleys with contrasting bedrock strength to widen in fundamentally different ways. The effect of distinct widening mechanisms on bedrock valley width remains unquantified. We analyze a new topographic data set from various lithologies that demonstrates that bedrock valleys in soft lithologies widen downstream twice as fast as valleys in intermediate lithologies. These downstream valley‐widening rates also emerge from landscape evolution model simulations using two end‐member valley‐widening mechanisms. The topographic data show that lithology and mechanism of valley widening are linked and that different widening mechanisms can control bedrock valley development along river courses.
A Study of Fluctuations in Magnetic Cloud‐Driven Sheaths
Authors: Moissard C. , Fontaine D. , Savoini P. 
Published: October 2019

AbstractInterplanetary coronal mass ejections are at the center of the research on geomagnetic activity. Sheaths, highly fluctuating structures, which can be found in front of fast interplanetary coronal mass ejections, are some of the least known geoeffective solar transients. Using Morlet transforms, we analyzed the magnetic fluctuations in a list of 42 well‐identified and isolated magnetic clouds driving a sheath and shock (Masías‐Meza et al., 2016, https://doi.org/10.1051/0004-6361/201628571. We studied the fluctuations inside sheaths by defining two quantities: the power and the anisotropy. With a simple statistical approach we found that sheaths, in particular, those driven by a fast magnetic cloud, encountering a highly turbulent solar wind, and forming a high Alfvén Mach number shock have high levels of turbulent energy (∼10 times compared with the solar wind) as well as a low anisotropy (approximately halved compared with the solar wind) of their fluctuations. On the other hand, the effect of the shock angle and plasma beta in the solar wind are less straightforward: If the shock is quasi‐parallel or the beta in the solar wind is high, both the turbulent energy in the sheaths and the anisotropy of the fluctuations are reduced; but for quasi‐perpendicular shocks or low beta solar wind the turbulent energy and anisotropy can take any value.
Stochastic TEC Structure Characterization
Authors: Rino Charles , Morton Yu , Breitsch Brian , Carrano Charles 
Published: October 2019

AbstractThe global navigation satellite systems provide high‐quality total electron content (TEC) measurements that are used routinely for ionospheric diagnostics. Large‐scale TEC structure is a critical input for maintaining global ionospheric models. However, residual stochastic TEC structure is typically discarded as a phase‐scintillation‐induced error. In this paper we show that the phase‐scintillation errors are a negligibly small fraction of the stochastic TEC component for most global navigation satellite system operating conditions. With three‐frequency GPS satellite measurements, two independent TEC measurements can be compared to bound the scintillation‐induced errors. Data analysis and simulations show that scintillation‐induced errors are a small fraction of one TEC unit as long as the lower contributing frequency S4 index is less than 0.5. To the extent that scintillation‐induced errors are negligible, spectral analysis of stochastic TEC provides a direct measure of path‐integrated structure. Irregularity parameter estimation can be used to estimate power law parameters, which in turn can be interpreted with a new global ionospheric structure model. We present a summary analysis of month‐long series of continuous measurements at Poker Flat, Alaska. The analysis confirms the generally accepted single power law model for high‐latitude structure. A small fraction of the measurements indicate an outer‐scale transition at approximately 17 km. The general pattern of the structure occurrence is consistent with auroral‐zone activity.
Dental anxiety in first- and final-year Indian dental students
Authors: Chowdhury Chitta Ranjan , Khijmatgar Shahnawaz , Chowdhury Avidyuti , Harding Stewart , Lynch Edward , Gootveld Martin 
Published: October 2019

Abstract
Objectives
The study aims to investigate dental anxiety in first- and final-year undergraduate dental students in India.

Design
Questionnaire Study Setting: BDS Students in four University dental colleges in India carried-out during 2013 and 2014.

Subjects (materials and methods)
The students (n = 614) were assessed using a pre-tested questionnaire. We estimated the level of dental anxiety by using the Modified-Dental-Anxiety-Scale (MDAS). ANCOVA and Mann–Whitney U, and Chi-squared contingency tests were employed to analyze the extensive dataset acquired. Univariate clustering analysis and principal component regression were also applied. Students had similar demographic and lifestyle patterns.

Interventions
Assessments of the level of dental anxiety amongst undergraduate dental students.

Main outcome measures
Mean ± SD MDAS scores for first- and final-year Bachelor of Dental Surgery (BDS) students were 12.96 ± 4.00 and 10.54 ± 3.41, respectively.

Results
Six hundred and fourteen (n = 614) students from four dental colleges were included in this study. In total 77% were female (n = 478) and 23% were male (n = 136). The mean age of the first- and final-year students were 18.31 and 21.54 years, respectively. First-year BDS students had dental anxiety score (Mean ± SD 12.96 ± 4.00) compared to that of the final year (10.54 ± 3.41), a difference which was very highly statistically significant (p < 0.0001).

Conclusion(s)
Dental anxiety was moderately higher amongst first year BDS students over that of final-year students but it is lesser than the dental phobic threshold level.
Microbe-host interplay in atopic dermatitis and psoriasis
Authors: Fyhrquist Nanna , Muirhead Gareth , Prast-Nielsen Stefanie , Jeanmougin Marine , Olah Peter , Skoog Tiina , Jules-Clement Gerome , Feld Micha , Barrientos-Somarribas Mauricio , Sinkko Hanna , van den Bogaard Ellen H. , Zeeuwen Patrick L.J.M. , Rikken Gijs , Schalkwijk Joost , Niehues Hanna , Däubener Walter , Eller Silvia Kathrin , Alexander Helen , Pennino Davide , Suomela Sari , Tessas Ioannis , Lybeck Emilia , Baran Anna M. , Darban Hamid , Gangwar Roopesh Singh , Gerstel Ulrich , Jahn Katharina , Karisola Piia , Yan Lee , Hansmann Britta , Katayama Shintaro , Meller Stephan , Bylesjö Max , Hupé Philippe , Levi-Schaffer Francesca , Greco Dario , Ranki Annamari , Schröder Jens M. , Barker Jonathan , Kere Juha , Tsoka Sophia , Lauerma Antti , Soumelis Vassili , Nestle Frank O. , Homey Bernhard , Andersson Björn , Alenius Harri 
Published: October 2019

AbstractDespite recent advances in understanding microbial diversity in skin homeostasis, the relevance of microbial dysbiosis in inflammatory disease is poorly understood. Here we perform a comparative analysis of skin microbial communities coupled to global patterns of cutaneous gene expression in patients with atopic dermatitis or psoriasis. The skin microbiota is analysed by 16S amplicon or whole genome sequencing and the skin transcriptome by microarrays, followed by integration of the data layers. We find that atopic dermatitis and psoriasis can be classified by distinct microbes, which differ from healthy volunteers microbiome composition. Atopic dermatitis is dominated by a single microbe (Staphylococcus aureus), and associated with a disease relevant host transcriptomic signature enriched for skin barrier function, tryptophan metabolism and immune activation. In contrast, psoriasis is characterized by co-occurring communities of microbes with weak associations with disease related gene expression. Our work provides a basis for biomarker discovery and targeted therapies in skin dysbiosis.
Epi-illumination gradient light interference microscopy for imaging opaque structures
Authors: Kandel Mikhail E. , Hu Chenfei , Naseri Kouzehgarani Ghazal , Min Eunjung , Sullivan Kathryn Michele , Kong Hyunjoon , Li Jennifer M. , Robson Drew N. , Gillette Martha U. , Best-Popescu Catherine , Popescu Gabriel 
Published: October 2019

AbstractMultiple scattering and absorption limit the depth at which biological tissues can be imaged with light. In thick unlabeled specimens, multiple scattering randomizes the phase of the field and absorption attenuates light that travels long optical paths. These obstacles limit the performance of transmission imaging. To mitigate these challenges, we developed an epi-illumination gradient light interference microscope (epi-GLIM) as a label-free phase imaging modality applicable to bulk or opaque samples. Epi-GLIM enables studying turbid structures that are hundreds of microns thick and otherwise opaque to transmitted light. We demonstrate this approach with a variety of man-made and biological samples that are incompatible with imaging in a transmission geometry: semiconductors wafers, specimens on opaque and birefringent substrates, cells in microplates, and bulk tissues. We demonstrate that the epi-GLIM data can be used to solve the inverse scattering problem and reconstruct the tomography of single cells and model organisms.
N6-methyladenosine modification of circNSUN2 facilitates cytoplasmic export and stabilizes HMGA2 to promote colorectal liver metastasis
Authors: Chen Ri-Xin , Chen Xin , Xia Liang-Ping , Zhang Jia-Xing , Pan Zhi-Zhong , Ma Xiao-Dan , Han Kai , Chen Jie-Wei , Judde Jean-Gabrie , Deas Olivier , Wang Feng , Ma Ning-Fang , Guan Xinyuan , Yun Jing-Ping , Wang Feng-Wei , Xu Rui-Hua , Dan Xie  
Published: October 2019

AbstractCircular RNAs (circRNAs) have been implicated in cancer progression through largely unknown mechanisms. Herein, we identify an N6-methyladenosine (m6A) modified circRNA, circNSUN2, frequently upregulated in tumor tissues and serum samples from colorectal carcinoma (CRC) patients with liver metastasis (LM) and predicts poorer patient survival. The upregulated expression of circNSUN2 promotes LM in PDX metastasis models in vivo and accelerates cancer cells invasion in vitro. Importantly, N6-methyladenosine modification of circNSUN2 increases export to the cytoplasm. By forming a circNSUN2/IGF2BP2/HMGA2 RNA-protein ternary complex in the cytoplasm, circNSUN2 enhances the stability of HMGA2 mRNA to promote CRC metastasis progression. Clinically, the upregulated expressions of circNSUN2 and HMGA2 are more prevalent in LM tissues than in primary CRC tissues. These findings elucidate that N6-methyladenosine modification of circNSUN2 modulates cytoplasmic export and stabilizes HMGA2 to promote CRC LM, and suggest that circNSUN2 could represent a critical prognostic marker and/or therapeutic target for the disease.
A Gas Phase Route to [18F]fluoroform with Limited Molar Activity Dilution
Authors: Yang Bo Yeun , Telu Sanjay , Haskali Mohammad B. , Morse Cheryl L. , Pike Victor W. 
Published: October 2019

AbstractPositron emission tomography (PET) is an important imaging modality for biomedical research and drug development. PET requires biochemically selective radiotracers to realize full potential. Fluorine-18 (t1/2 = 109.8 min) is a major radionuclide for labeling such radiotracers but is only readily available in high activities from cyclotrons as [18F]fluoride ion. [18F]fluoroform has emerged for labeling tracers in trifluoromethyl groups. Prior methods of [18F]fluoroform synthesis used difluoro precursors in solution and led to high dilution with carrier and low molar activity (Am). We explored a new approach for the synthesis of [18F]fluoroform based on the radiosynthesis of [18F]fluoromethane from [18F]fluoride ion and then cobaltIII fluoride mediated gas phase fluorination. We estimate that carrier dilution in this process is limited to about 3-fold and find that moderate to high Am values can be achieved. We show that [18F]fluoroform so produced is highly versatile for rapidly and efficiently labeling various chemotypes that carry trifluoromethyl groups, thereby expanding prospects for developing new PET radiotracers.
Sub-optimality in motor planning is not improved by explicit observation of motor uncertainty
Authors: Ota Keiji , Shinya Masahiro , Maloney Laurence T. , Kudo Kazutoshi 
Published: October 2019

AbstractTo make optimal decisions under risk, one must correctly weight potential rewards and penalties by the probabilities of receiving them. In motor decision tasks, the uncertainty in outcome is a consequence of motor uncertainty. When participants perform suboptimally as they often do in such tasks, it could be because they have insufficient information about their motor uncertainty: with more information, their performance could converge to optimal as they learn their own motor uncertainty. Alternatively, their suboptimal performance may reflect an inability to make use of the information they have or even to perform the correct computations. To discriminate between these two possibilities, we performed an experiment spanning two days. On the first day, all participants performed a reaching task with trial-by-trial feedback of motor error. At the end of the day, their aim points were still typically suboptimal. On the second day participants were divided into two groups one of which repeated the task of the first day and the other of which repeated the task but were intermittently given additional information summarizing their motor errors. Participants receiving additional information did not perform significantly better than those who did not.
Characterization of all second-order nonlinear-optical coefficients of organic N-benzyl-2-methyl-4-nitroaniline crystal
Authors: Notake Takashi , Takeda Masahiro , Okada Shuji , Hosobata Takuya , Yamagata Yutaka , Minamide Hiroaki 
Published: October 2019

AbstractFull elements of second-order nonlinear optical (NLO) tensor can be completely characterized for an organic NLO crystal for the first time. As-grown bulk N-benzyl-2-methyl-4-nitroaniline (BNA) crystal was processed to expose (100) and (010) crystal orientations with fine optical surfaces by using precision lathe and diamond blade. Then, every five nonvanishing second-order NLO coefficient of BNA can be determined quantitatively using the precisely processed crystals based on 1st-kind Maker fringe measurements. Our method makes it possible to clarify uncertain NLO property of any organic materials and to accelerate application study via precise device fabrications even for fragile organic materials.
Structural and biochemical characterisation of a novel alginate lyase from Paenibacillus sp. str. FPU-7
Authors: Itoh Takafumi , Nakagawa Emi , Yoda Moe , Nakaichi Akari , Hibi Takao , Kimoto Hisashi 
Published: October 2019

AbstractA novel alginate lyase, PsAly, with a molecular mass of 33 kDa and whose amino acid sequence shares no significant similarity to other known proteins, was biochemically and structurally characterised from Paenibacillus sp. str. FPU-7. The maximum PsAly activity was obtained at 65 °C, with an optimum pH of pH 7–7.5. The activity was enhanced by divalent cations, such as Mg2+, Mn2+, or Co2+, and inhibited by a metal chelator, ethylenediaminetetraacetic acid. The reaction products indicated that PsAly is an endolytic enzyme with a preference for polymannuronate. Herein, we report a detailed crystal structure of PsAly at a resolution of 0.89 Å, which possesses a β-helix fold that creates a long cleft. The catalytic site was different from that of other polysaccharide lyases. Site-directed mutational analysis of conserved residues predicted Tyr184 and Lys221 as catalytic residues, abstracting from the C5 proton and providing a proton to the glycoside bond, respectively. One cation was found to bind to the bottom of the cleft and neutralise the carboxy group of the substrate, decreasing the pKa of the C5 proton to promote catalysis. Our study provides an insight into the structural basis for the catalysis of alginate lyases and β-helix polysaccharide lyases.
Study of the effect of Sn grain boundaries on IMC morphology in solid state inter-diffusion soldering
Authors: Hou Lin , Moelans Nele , Derakhshandeh Jaber , De Wolf Ingrid , Beyne Eric 
Published: October 2019

AbstractThis paper reports on 3D phase field simulations of IMC growth in Co/Sn and Cu/Sn solder systems. In agreement with experimental micrographs, we obtain uniform growth of the CoSn3 phase in Co/Sn solder joints and a non-uniform wavy morphology for the Cu6Sn5 phase in Cu/Sn solder joints. Furthermore, simulations were performed to obtain an insight in the impact of Sn grain size, grain boundary versus bulk diffusion, IMC/Sn interface mobility and Sn grain boundary mobility on IMC morphology and growth kinetics. It is found that grain boundary diffusion in the IMC or Sn phase have a limited impact on the IMC evolution. A wavy IMC morphology is obtained in the simulations when the grain boundary mobility in the Sn phase is relatively large compared to the interface mobility for the IMC/Sn interface, while a uniform IMC morphology is obtained when the Sn grain boundary and IMC/Sn interface mobilities are comparable. For the wavy IMC morphology, a clear effect of the Sn grain size is observed, while for uniform IMC growth, the effect of the Sn grain size is negligible.
Low erythropoietin levels predict faster renal function decline in diabetic patients with anemia: a prospective cohort study
Authors: Fujita Yohei , Doi Yohei , Hamano Takayuki , Hatazaki Masahiro , Umayahara Yutaka , Isaka Yoshitaka , Tsubakihara Yoshiharu 
Published: October 2019

AbstractElevated erythropoietin (EPO) levels have been reported to predict poor survival in various populations including diabetic patients. However, data regarding its impact on renal outcomes are scarce. We conducted a single-center, prospective cohort study of 339 type 2 diabetic patients with anemia. The primary outcome was the estimated glomerular filtration rate (eGFR) slope for two years. We performed multiple linear regression and restricted cubic spline analyses to assess the association of serum EPO levels with the renal outcome. Chronic kidney disease (CKD) was defined as eGFR <60 mL/min/1.73 m2 or urine albumin-to-creatinine ratio >30 mg/g creatinine. Median baseline EPO and eGFR level were 14.4 IU/L and 53 mL/min/1.73 m2, respectively. Inappropriately low EPO levels were observed in 73% of anemic patients and 59% of anemic patients even without CKD, suggesting that EPO deficiency precedes the onset of CKD in diabetes mellitus. Multivariable analysis revealed that iron status and hemoglobin levels were major determinants of EPO levels. Median eGFR slope was −1.3 mL/min/1.73 m2/year. We found that low EPO levels, but not low hemoglobin levels, were associated with a faster decline in eGFR, independent of clinically relevant factors. The eGFR decline was steeper, particularly when the EPO level was below the upper limit of normal. Lower EPO concentrations were associated with rapid eGFR decline, especially in patients with iron deficiency (P for interaction = 0.01). Relative EPO deficiency should be considered as a culprit in anemia of unknown etiology in diabetic patients, even those without CKD. Low EPO levels, especially when accompanied by poor iron status, are predictive of rapid loss of renal function.
Coupling Multi-Angle Light Scattering to Reverse-Phase Ultra-High-Pressure Chromatography (RP-UPLC-MALS) for the characterization monoclonal antibodies
Authors: Gentiluomo Lorenzo , Schneider Vanessa , Roessner Dierk , Frieß Wolfgang 
Published: October 2019

AbstractMulti-angle light scattering coupled with size-exclusion chromatography (SEC-MALS) is a standard approach for protein characterization. Recently MALS detection has been coupled with ion-exchange chromatography (IEX) which demonstrated the feasibility and high value of MALS in combination with non-sized-based fractionation methods. In this study we coupled reverse-phase ultra-high pressure liquid chromatography (RP-UPLC) with a low-dispersion MALS detector for the characterization of intact monoclonal antibody (mAbs) and their fragments. We confirmed a constant refractive index increment value for mAbs in RP gradients, in good agreement with the values in literature for other classes of proteins. We showed that the impurities eluting from a RP column can often be related to aggregated species and we confirmed that in most cases those oligomers are present also in SEC-MALS. Yet, in few cases small aggregates fractions in RP-UPLC are an artifact. In fact, proteins presenting thermal and physical stability not suitable for the harsh condition applied during the RP separation of mAbs (i.e. organic solvents at high temperature) can aggregate. Further, we applied RP-UPLC-MALS during a long term stability studies. The different principle of separation used in RP-UPLC- MALS provides an additional critical level of protein characterization compared to SEC-MALS and IEX-MALS.