bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extensive analysis of native and non-native Centaurea solstitialis L. populations across the world shows no traces of polyploidization
Authors: Irimia Ramona-Elena , Montesinos Daniel , Eren Özkan , Lortie Christopher J. , French Kristine , Cavieres Lohengrin A. , Sotes Gastón J. , Hierro José L. , Jorge Andreia , Loureiro João 
Published: August 2017

Centaurea solstitialis L. (yellow starthistle, Asteraceae) is a Eurasian native plant introduced as an exotic into North and South America, and Australia, where it is regarded as a noxious invasive. Changes in ploidy level have been found to be responsible for numerous plant biological invasions, as they are involved in trait shifts critical to invasive success, like increased growth rate and biomass, longer life-span, or polycarpy. C. solstitialis had been reported to be diploid (2n = 2x = 16 chromosomes), however, actual data are scarce and sometimes contradictory. We determined for the first time the absolute nuclear DNA content by flow cytometry and estimated ploidy level in 52 natural populations of C. solstitialis across its native and non-native ranges, around the world. All the C. solstitialis populations screened were found to be homogeneously diploid (average 2C value of 1.72 pg, SD = ±0.06 pg), with no significant variation in DNA content between invasive and non-invasive genotypes. We did not find any meaningful difference among the extensive number of native and non-native C. solstitialis populations sampled around the globe, indicating that the species invasive success is not due to changes in genome size or ploidy level.
High‐resolution hyperspectral imaging of diagenesis and clays in fossil coral reef material: a nondestructive tool for improving environmental and climate reconstructions
Authors: Murphy R. J. , Webster J. M. , Nothdurft L. , Dechnik B. , McGregor H. V. , Patterson M. A. , Sanborn K. L. , Webb G. E. , Kearney L. I. , Rintoul L. , Erler D. V. 
Published: August 2017

AbstractHyperspectral imagery (1000–2500 nm) was used to quantitatively map carbonate and clay minerals in fossil reef cores that are relevant to accurately reconstructing past environmental and climatic conditions. Techniques were developed using hyperspectral imagery of fossil reef corals and cores acquired from three different geological settings, and were validated against independent measures of calcite to aragonite ratios. Aragonite, calcite, and dolomite were distinguished using a combination of the wavelength position and asymmetry of the primary carbonate absorption between 2300 and 2350 nm. Areas of core containing small amounts of calcite (>2–5%) were distinguished from aragonite in imagery of two cores, enabling quantitative maps of these minerals to be constructed. Dolomite was found to be the dominant mineral in another core. Trace amounts of the aluminium‐rich clay mineral kaolinite were detected, quantified, and mapped in one core using its diagnostic absorption feature near 2200 nm. The amounts of clay detected from hyperspectral imagery were below the limits of detection by standard X‐ray diffraction techniques but its presence was confirmed by Fourier Transform Infrared Spectroscopy. Hyperspectral imagery acquired at high spatial resolution simplifies vetting procedures for secondary carbonate minerals in coral reef cores, significantly reduces sampling time and costs, and is a powerful nondestructive tool to identify well‐preserved coral aragonite in cores for uses in paleoclimate, paleoenvironment and paleoecosystem reconstruction.
The impact of lidar detection sensitivity on assessing aerosol direct radiative effects
Authors: Thorsen Tyler J. , Ferrare Richard A. , Hostetler Chris A. , Vaughan Mark A. , Fu Qiang 
Published: August 2017

AbstractSpaceborne lidar observations have great potential to provide accurate global estimates of the aerosol direct radiative effect (DRE) in both clear and cloudy conditions. However, comparisons between observations from the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite (CALIPSO) and multiple years of Atmospheric Radiation Measurement (ARM) program's ground‐based Raman lidars (RL) show that CALIPSO does not detect all radiatively significant aerosol, i.e., aerosol that directly modifies the Earth's radiation budget. We estimated that using CALIPSO observations results in an underestimate of the magnitude of the global mean aerosol DRE by up to 54%. The ARM RL data sets along with NASA Langley airborne high spectral resolution lidar data from multiple field campaigns are used to derive the detection sensitivity required to accurately resolve the aerosol DRE. This shows that a lidar with a backscatter coefficient detection sensitivity of about 1–2 × 10−4 km−1 sr−1 at 532 nm would resolve all the aerosol needed to derive the DRE to within 1%.
Factors controlling Hadley circulation changes from the Last Glacial Maximum to the end of the 21st century
Authors: D'Agostino Roberta , Lionello Piero , Adam Ori , Schneider Tapio 
Published: August 2017

AbstractThe Hadley circulation (HC) extent and strength are analyzed in a wide range of simulated climates from the Last Glacial Maximum to global warming scenarios. Motivated by HC theories, we analyze how the HC is influenced by the subtropical stability, the near‐surface meridional potential temperature gradient, and the tropical tropopause level. The subtropical static stability accounts for the bulk of the HC changes across the simulations. However, since it correlates strongly with global mean surface temperature, most HC changes can be attributed to global mean surface temperature changes. The HC widens as the climate warms, and it also weakens, but only robustly so in the Northern Hemisphere. On the other hand, the Southern Hemisphere strength response is uncertain, in part because subtropical static stability changes counteract meridional potential temperature gradient changes to various degrees in different models, with no consensus on the response of the latter to global warming.
Different composition and distribution patterns of mineral‐protected versus hydrolyzable lipids in shrubland soils
Authors: Cai Yue , Tang Zhiyao , Xiong Gaoming , Xie Zongqiang , Liu Zongguang , Feng Xiaojuan 
Published: August 2017

AbstractMineral protection is known as an important mechanism stabilizing soil organic carbon (SOC). However, the composition, sources, and variations of mineral‐protected SOC remain poorly constrained. To fill this knowledge gap, we used hydrofluoric acid to demineralize soil matrix and compared the sources and distribution of mineral‐protected lipids (ML) versus hydrolyzable lipids (HL) of four typical Chinese shrubland soils. ML was found to represent a sizable fraction (9–32%) of total aliphatic lipids (including n‐alkanols; n‐alkanoic acids; α,ω‐alkanedioic acids; hydroxyalkanoic acids; and midchain‐substituted acids) in all soils. Based on carbon chain length and branch positions, microbe‐ and plant‐derived lipids were distinguished. No significant difference was found in the ratio of microbe‐ to plant‐derived lipids in ML versus HL, implying that plant and microbial inputs are equally important for the mineral‐associated soil lipids. However, ML contained a higher proportion of nonspecific lipids, especially at depths. Furthermore, to evaluate key environmental variable(s) controlling the distribution of different lipid components, a multiple stepwise regression analysis was conducted. Notably, ML was mainly affected by SOC‐to‐nitrogen ratio instead of mineralogical properties, implying that the accrual of mineral‐associated soil lipids relies strongly on organic matter properties. Collectively, our findings provide novel insights on sources and accumulation mechanisms of mineral‐protected soil lipids. SOC decomposition and subsequent accretion of degradation products appear to be vital for the sequestration of mineral‐associated soil lipids and warrant better recognition in the investigations of stable soil carbon accumulation mechanisms.
Soil CO2concentrations and efflux dynamics of a tree island in the Pantanal wetland
Authors: Lathuillière Michael J. , Pinto Osvaldo B. , Johnson Mark S. , Jassal Rachhpal S. , Dalmagro Higo J. , Leite Nei K. , Speratti Alicia B. , Krampe Daniela , Couto Eduardo G. 
Published: August 2017

AbstractThe Pantanal is the largest tropical wetland on the planet, and yet little information is available on the biome's carbon cycle. We used an automatic station to measure soil CO2concentrations and oxidation‐reduction potential over the 2014 and 2015 flood cycles of a tree island in the Pantanal that is immune to inundation during the wetland's annual flooding. The soil CO2concentration profile was then used to estimate soil CO2efflux over the two periods. In 2014, subsurface soil saturation at 0.30 m depth created conditions in that layer that led to CO2buildup close to 200,000 ppm and soil oxidation‐reduction potential below −300 mV, conditions that were not repeated in 2015 due to annual variability in soil saturation at the site. Mean CO2efflux over the 2015 flood cycle was 0.023 ± 0.103 mg CO2‐C m−2 s−1representing a total annual efflux of 593 ± 2690 mg CO2‐C m−2 y−1. Unlike a nearby tree island site that experiences full inundation during the wet season, here the soil dried quickly following repeated rain events throughout the year, which led to the release of CO2pulses from the soil. This study highlights not only the complexity and heterogeneity in the Pantanal's carbon balance based on differences in topography, flood cycles, and vegetation but also the challenges of applying the gradient method in the Pantanal due to deviations from steady state conditions.
Forecasting the Dst index using a swarm‐optimized neural network
Authors: Lazzús J. A. , Vega P. , Rojas P. , Salfate I. 
Published: August 2017

AbstractA hybrid technique that combines an artificial neural network with a particle swarm optimization (ANN+PSO) was used to forecast the disturbance storm time (Dst) index from 1 to 6 h ahead. Our ANN was optimized by PSO to update ANN weights and to predict the short‐term Dst index using past values as input parameters. The database used contains 233,760 hourly data from 1 January 1990 to 31 August 2016, considering storms and quiet period, grouped into three data sets: learning set (with 116,880 hourly data points), validation set (with 58,440 data points), and testing set (with 58,440 data points). Several ANN topologies were studied, and the best architecture was determined by systematically adding neurons and evaluating the root‐mean‐square error (RMSE) and the correlation coefficient (R) during the training process. These results show that the hybrid algorithm is a powerful technique for forecasting the Dst index a short time in advance like t + 1 to t + 3, with RMSE from 3.5 nT to 7.5 nT, and R from 0.98 to 0.90. However, t + 4 to t + 6 predictions become slightly more uncertain, with RMSE from 8.8 nT to 10.9 nT, and R from 0.86 to 0.79. Additionally, an exhaustive analysis according to geomagnetic storm magnitude was conducted. In general, the results show that our hybrid algorithm can be correctly trained to forecast the Dst index with appropriate precision and that Dst past behavior significantly affects adequate training and predicting capabilities of the implemented ANN.
Midlatitude postsunset plasma bubbles observed over Europe during intense storms in April 2000 and 2001
Authors: Katamzi‐Joseph Zama Thobeka , Habarulema John Bosco , Hernández‐Pajares Manuel 
Published: August 2017

AbstractPlasma bubbles are prevalent features of the equatorial/low‐latitude ionosphere which are seldom observed at middle and high latitudes. Understanding the influence of geomagnetic storms on plasma bubbles' migration to higher latitudes is an important space weather topic, since a geomagnetic storm is an important phenomenon of space weather. This paper reports on the first observations of postsunset/evening midlatitude plasma bubbles in the European sector during the main phase of severe storms (Dst≤−200 nT) on 6 April 2000 and 11 April 2001. Plasma depletions observed in Global Navigation Satellite System total electron content measurements are confirmed with those observed from in situ Defense Meteorological Satellite Program ion density measurements. The results show that the plasma bubbles were migrating north at virtual speeds of 400 m/s and on each of the storm days they extended as far north as ∼42° (geographic latitude). It is estimated that the plasma bubbles may have grown to a maximum apex height of approximately 4000 km. During the time of bubble occurrence, the evening midlatitude plasma was enhanced and the equatorial ionization anomaly extended to European midlatitudes. In addition, evidence of the upward plasma motion was found in ionosonde hmF2 and h'F measurements, while the interplanetary electric field Ey was enhanced. This was found to suggest that the possible mechanism for the enhancement of midlatitude plasma and subsequent midlatitude plasma bubbles occurrence was the eastward penetration electric field associated with Bz southward turning.
Pain Catastrophizing, Subjective Outcomes, and Inflammatory Assessments Including Ultrasound: Results From a Longitudinal Study of Rheumatoid Arthritis Patients
Authors: Hammer Hilde B. , Uhlig Till , Kvien Tore K. , Lampa Jon 
Published: August 2017

ObjectivePain catastrophizing is conceptualized as a negative cognitive–affective response to anticipated or actual pain and has been associated with important pain‐related outcomes. The objective of this prospective study of established rheumatoid arthritis (RA) patients was to explore how pain catastrophizing was related to patient‐reported outcomes (PROs), composite scores, and assessments of inflammatory activity.MethodsRA patients starting biologic disease‐modifying antirheumatic drugs were examined at baseline and after 1, 2, 3, 6, and 12 months with PROs (joint pain/patient's global visual analog scale [VAS], modified Health Assessment Questionnaire, Rheumatoid Arthritis Impact of Disease score), clinical and laboratory assessments (tender/swollen joint count, assessor's global VAS, erythrocyte sedimentation rate/C‐reactive protein [CRP] level), ultrasound (US) (gray scale [GS]/power Doppler [PD] of 36 joints and 4 tendons), and pain catastrophizing. The composite scores for Disease Activity Score in 28 joints, Clinical Disease Activity Index, and Simplified Disease Activity Index were calculated. Statistical calculations included independent samples t‐test, paired samples t‐test, one‐way analysis of variance, Pearson's correlations, and linear and logistic regression.ResultsOf 209 patients included, 152 (72.7%) completed 12‐month followup. Pain catastrophizing, PROs, and clinical and inflammatory assessments decreased significantly (P < 0.001). Pain catastrophizing was strongly correlated with the PROs and composite scores (P < 0.001) but not with the inflammatory parameters (swollen joint count, CRP level, and GS/PD US). Patients with higher levels of pain catastrophizing had higher PROs and composite scores during the study (P < 0.001) but not inflammatory assessments. Baseline pain catastrophizing was negatively associated with achievement of remission at 6 and 12 months (P < 0.05).ConclusionPain catastrophizing was strongly associated with PROs and composite measures, but not with markers of inflammation. High levels of pain catastrophizing reduced the likelihood of achieving composite score remission and should be a factor to consider in a treat‐to‐target strategy.
A Benchmark Quantum Yield for Water Photoreduction on Amorphous Carbon Nitride
Authors: Rahman Mohammad Z. , Tapping Patrick C. , Kee Tak W. , Smernik Ronald , Spooner Nigel , Moffatt Jillian , Tang Youhong , Davey Kenneth , Qiao Shi‐Zhang 
Published: August 2017

AbstractAmorphous carbon nitride (a‐CN) is a less‐explored but promising photocatalyst for hydrogen production. Despite an extended visible light absorption (EVLA) its low quantum efficiency (QE) for water photoreduction is a long standing problem. This implies that EVLA is not proportionally translated into collection of large amounts of photogenerated electrons. Minimizing the mismatch between light‐absorption and charge‐collection remains a scientific challenge. Here a sponge‐like hierarchical structure of a‐CN that addresses this apparent mismatch is reported. Combined experimental and finite difference time domain simulations demonstrate the ability of the a‐CN sponge to induce scattering for total internal light reflection that promotes localized charge carrier generation. Diffused reflectance and transient fluorescence decay studies show good agreement with simulations with a 40% enhanced light‐trapping and an ≈23 times longer electron lifetime in spongy a‐CN compared with that of the bulk material. The result is a new high benchmark for hydrogen production of 203.5 µmol h−1 with a QE of 6.1% at 420 nm in a reaction system of 10 vol% triethanolamine and 1 wt% Pt cocatalyst. The enhanced water photoreduction is a result of amenable photophysical and electrochemical attributes existing within the a‐CN sponge.
3D Bioprinting for Cartilage and Osteochondral Tissue Engineering
Authors: Daly Andrew C. , Freeman Fiona E. , Gonzalez‐Fernandez Tomas , Critchley Susan E. , Nulty Jessica , Kelly Daniel J. 
Published: August 2017

AbstractSignificant progress has been made in the field of cartilage and bone tissue engineering over the last two decades. As a result, there is real promise that strategies to regenerate rather than replace damaged or diseased bones and joints will one day reach the clinic however, a number of major challenges must still be addressed before this becomes a reality. These include vascularization in the context of large bone defect repair, engineering complex gradients for bone‐soft tissue interface regeneration and recapitulating the stratified zonal architecture present in many adult tissues such as articular cartilage. Tissue engineered constructs typically lack such spatial complexity in cell types and tissue organization, which may explain their relatively limited success to date. This has led to increased interest in bioprinting technologies in the field of musculoskeletal tissue engineering. The additive, layer by layer nature of such biofabrication strategies makes it possible to generate zonal distributions of cells, matrix and bioactive cues in 3D. The adoption of biofabrication technology in musculoskeletal tissue engineering may therefore make it possible to produce the next generation of biological implants capable of treating a range of conditions. Here, advances in bioprinting for cartilage and osteochondral tissue engineering are reviewed.
Site‐Selective Rhodium(III)‐Catalyzed C−H Amination of 7‐Azaindoles with Anthranils: Synthesis and Anticancer Evaluation
Authors: Jeon Mijin , Park Jihye , Dey Prasanta , Oh Yongguk , Oh Hyunjung , Han Sangil , Um Sung Hee , Kim Hyung Sik , Mishra Neeraj Kumar , Kim In Su 
Published: August 2017

AbstractThe site‐selective C−H amination reaction of 7‐azaindoles with various benzisoxazoles as amination surrogates under cationic rhodium(III) catalysis is described. This transformation efficiently provides a range of ortho‐aminated N‐aryl‐7‐azaindoles with excellent site‐selectivity and functional group compatibility. The formed ortho‐aminated 7‐azaindoles were readily transformed into biologically relevant heterocycles such as azaindoloacridine, azaindoloacridone, and bis‐indole compounds. Moreover, the synthetic derivatives were tested for in vitro anticancer activity against human breast adenocarcinoma cells (MCF‐7), human renal carcinoma cells (786‐O), and human prostate adenocarcinoma cells (DU145). Notably, some synthetic compounds were found to display most potent anticancer activity, compared to that of anticancer doxorubicin as a positive control.magnified image
Technical details of video‐assisted transcervical mediastinal dissection for esophageal cancer and its perioperative outcome
Authors: Mori Kazuhiko , Aikou Susumu , Yagi Koichi , Nishida Masato , Mitsui Takashi , Yamagata Yukinori , Yamashita Hiroharu , Nomura Sachiyo , Seto Yasuyuki 
Published: August 2017

AbstractTo reduce pulmonary complications after esophagectomy, the transthoracic procedure should be shortened or totally avoided. Transcervical approach assisted by mediastinoscope for the upper mediastinum may be advantageous for this purpose. We carried out video‐assisted transcervical mediastinal dissection (VATCMD) as part of totally non‐transthoracic radical esophagectomy. A single‐port laparoscopy device was adopted to a small cervical incision and the mediastinum was inflated with a positive pressure of 6 to 10 mmHg. Without assistant's retractor, the upper mediastinum and partially the middle mediastinum were dissected mainly by mediastinoscopic‐assisted surgery. Video of the operation is demonstrated with illustrations. We have carried out and reported 17 cases of esophagectomy including VATCMD and its perioperative outcome. Non‐transthoracic esophagectomy was completed without conversion to transthoracic procedure in all 17 cases. Procedure‐related adverse event was not observed and postoperative course was favorable with a zero occurrence (0%) of recurrent laryngeal nerve palsy, chyle leakage or pulmonary complications. Median number of harvested lymph nodes from the upper mediastinal stations was 10. VATCMD is suggested as a safe and feasible approach for the upper mediastinum in esophagectomy for malignancies. It enabled a totally non‐transthoracic radical esophagectomy in combination with a transhiatal approach.Video‐assisted transcervical mediastinal dissection is suggested as a safe and feasible approach for the upper mediastinum in esophagectomy for malignancies. It enabled a totally non‐transthoracic radical esophagectomy in combination with a transhiatal approach.
Local control of sphincter‐preserving procedures and abdominoperineal resection for locally advanced low rectal cancer: Propensity score matched analysis
Authors: Okamura Ryosuke , Hida Koya , Yamaguchi Tomohiro , Akagi Tomonori , Konishi Tsuyoshi , Yamamoto Michio , Ota Mitsuyoshi , Matoba Shuichiro , Bando Hiroyuki , Goto Saori , Sakai Yoshiharu , Watanabe Masahiko ,   Japan Society of Laparoscopic Colorectal Surgery
Published: August 2017

AbstractSphincter‐preserving procedures (SPPs) for surgical treatment of low‐lying rectal tumors have advanced considerably. However, their oncological safety for locally advanced low rectal cancer compared with abdominoperineal resection (APR) is contentious. We retrospectively analyzed cohort data of 1500 consecutive patients who underwent elective resection for stage II‐III rectal cancer between 2010 and 2011. Patients with tumors 2‐5 cm from the anal verge and clinical stage T3‐4 were eligible. Primary outcome was 3‐year local recurrence rate, and confounding effects were minimized by propensity score matching. The study involved 794 patients (456 SPPs and 338 APR). Before matching, candidates for APR were more likely to have lower and advanced lesions, whereas SPPs were carried out more often following preoperative treatment, by laparoscopic approach, and at institutions with higher case volume. After matching, 398 patients (199 each for SPPs and APR) were included in the analysis sample. Postoperative morbidity was similar between the SPPs and APR groups (38% vs 39%; RR 0.98, 95% CI 0.77‐1.27). Margin involvement was present in eight patients in the SPPs group (one and seven at the distal and radial margins, respectively) and in 12 patients in the APR group. No difference in 3‐year local recurrence rate was noted between the two groups (11% vs 14%; HR 0.77, 95% CI 0.42‐1.41). In this observational study, comparability was ensured by adjusting for possible confounding factors. Our results suggest that SPPs and APR for locally advanced low rectal cancer have demonstrably equivalent oncological local control.