bluuebunny/crossref_metadata_2025_split huggingface dataset:
How well does the European Centre for Medium‐Range Weather Forecasting Interim Reanalysis represent the surface air temperature in Cuban weather stations?
Authors: Rodríguez‐Vega Albeht , Antuña‐Marrero Juan C. , Mesquita Michel D. S. , Robock Alan , Toniazzo Thomas , Otterå Odd H. 
Published: September 2017

ABSTRACTIn this research, we compare 2‐m air temperature from the ERA‐Interim reanalysis of the European Centre for Medium‐Range Weather Forecasting with 2‐m air temperature weather station observations in Cuba, with the goal of evaluating the behaviour and uncertainties of the ERA‐Interim data set with respect to station‐based observations. Three interpolation methods are used to determine 2‐m temperatures from the ERA‐Interim data set at the station locations. The differences were analysed utilizing root mean square error (RMSE), mean absolute error (MAE) and bias. The comparison was conducted for daily, monthly and annual time scales, and for the rainy (May–October) and less rainy (November–April) seasons. The best interpolation method is the mean of four grid points method. We find a warm bias in the ERA‐Interim reanalysis for most Cuban stations. The smallest differences are at 1800 UTC and the largest differences are at 1200 UTC. All differences are greater than 0.3 K, although many of the stations show differences in the range of 1.5–2.0 K. In some stations the differences are greater than 5.0 K. At the daily scale more than 50% of the stations show significant differences at the 95% confidence level. The differences are caused by the altitude difference between the stations and the nearest grid point of ERA‐Interim, the land‐sea mask of ERA‐Interim and the station location respect to this mask, and by local processes, such as a local breeze. At the monthly scale there are fewer stations with significant differences than for the other time scales. The ERA‐Interim reanalysis better represents the surface 2‐m temperature for coastal stations than for inland stations. Years with moderate and strong El Niño or La Niña show significant differences between ERA‐Interim and observations. The amplitude between the maximum bias and the minimum bias is greater in those years.
An event synchronization method to link heavy rainfall events and large‐scale atmospheric circulation features
Authors: Conticello Federico , Cioffi Francesco , Merz Bruno , Lall Upmanu 
Published: September 2017

ABSTRACTHeavy rainfall, floods and other hydroclimatic extremes may be related to specific states of organization of the atmospheric circulation. The identification of these states and their linkage to local extremes could facilitate a physically meaningful quantification of local extremes in future climates and could allow forecasting extremes conditioned on the large‐scale atmospheric state. A novel methodology is presented that combines non‐linear, non‐parametric methods to link heavy precipitation events (HPEs) to atmospheric circulation states. Using daily rainfall data for the period 1951–2015 from 37 gauges in the Lazio region in Italy, HPEs are defined. For the same period, two atmospheric variables, namely, the 850 hPa geopotential height field and the integrated vapour transport (IVT), are derived from reanalysis data. The geopotential configurations driving heavy precipitation in the region are identified by combing self‐organized maps and event synchronization. First, a finite number of representative geopotential configurations is identified. Rainfall gauges are pooled into clusters, which show synchronized occurrence of heavy precipitation. Furthermore, geopotential configurations are identified, which tend to drive HPEs. For these geopotential states, the probability of HPE occurrence as a function of IVT is calculated through a local logistic regression model. Finally, it is explored whether the identified patterns are related to the occurrence of atmospheric rivers, which govern the atmospheric humidity transport from the tropics and subtropics to Europe. The relation found demonstrates the reliability of the proposed methodology.
Climatic and non‐climatic controls shaping early postglacial conifer history in the northern Greater Yellowstone Ecosystem, USA
Authors: Krause Teresa R. , Whitlock Cathy 
Published: September 2017

ABSTRACTMountain ecosystems are characterized by their complex vegetation responses to past climate variability because of the interplay between large‐scale climate changes and local‐scale biotic and abiotic conditions. This study reconstructs the early postglacial expansion of conifer populations in the northern Greater Yellowstone Ecosystem (GYE). The objective is to examine how climate change and non‐climatic factors, including species characteristics, edaphic conditions and disturbance, governed postglacial vegetation changes. Spruce populations expanded first at 13 300 cal a BP, concurrent with soil development and warming summers. Subalpine fir populations expanded after 12 300 cal a BPand probably lagged spruce expansion due to differences in climatic tolerances and/or its poorer seed dispersing capacity. Pine species expanded nearly synchronously after 11 300 cal a BPin response to elevated summer temperatures and increased fire activity. Douglas‐fir populations expanded last after 10 200 cal a BPduring the early Holocene summer insolation maximum and cooler winters. The sequence and timing of conifer expansions in the northern GYE are consistent with the regional conifer history, indicating strong vegetation responses to millennial‐scale climate change associated with the seasonal cycle of insolation across spatial scales. Nonetheless, non‐climatic factors, including landscape stabilization and subsequent soil development, seed dispersing characteristics and fire, still shaped local‐scale patterns of conifer expansion.
Monascus‐fermented red mold dioscorea protects mice against alcohol‐induced liver injury, whereas its metabolites ankaflavin and monascin regulate ethanol‐induced peroxisome proliferator‐activated receptor‐γ and sterol regulatory element‐binding transcription factor‐1 expression in HepG2 cells
Authors: Cheng Chih‐Fu , Pan Tzu‐Ming 
Published: September 2017

AbstractBACKGROUNDAlcoholic hepatitis is a necroinflammatory process that is associated with fibrosis and leads to cirrhosis in 40% of cases. The hepatoprotective effects of red mold dioscorea (RMD) from Monascus purpureus NTU 568 were evaluated in vivo using a mouse model of chronic alcohol‐induced liver disease (ALD).RESULTSALD mice were orally administered vehicle (ALD group) or vehicle plus 307.5, 615.0 or 1537.5 mg kg–1 (1 ×, 2 × and 5 ×) RMD for 5 weeks. RMD lowered serum leptin, hepatic total cholesterol, free fatty acid and hepatic triglyceride levels and increased serum adiponectin, hepatic alcohol dehydrogenase and antioxidant enzyme levels. Furthermore, ankaflavin (AK) and monascin (MS), metabolites of RMD fermented with M. purpureus 568, induced peroxisome proliferator‐activated receptor‐γ expression and the concomitant suppression of ethanol‐induced elevation of sterol regulatory element‐binding transcription factor‐1 and TG in HepG2 cells.CONCLUSIONThese results indicate the hepatoprotective effect of Monascus‐fermented RMD. Moreover, AK and MS were identified as the active constituents of RMD for the first time and were shown to protect against ethanol‐induced liver damage. © 2017 Society of Chemical Industry
Inhibition of influenza virus replication by adlay tea
Authors: Nagai Emiko , Iwai Miwa , Koketsu Ritsuko , Sogabe Riho , Morimoto Ryosuke , Suzuki Yuri , Ohta Yoichiro , Okuno Yoshinobu , Ohshima Atsushi , Enomoto Toshiki , Isegawa Yuji 
Published: September 2017

AbstractBACKGROUNDThe present study was conducted aiming to examine the antiviral activity of adlay tea and its components against influenza viruses. We further aimed to clarify the mechanism by which these components regulate virus replication.RESULTSAdlay tea at a concentration suitable for drinking inhibited the multiplication of influenza viruses. Moreover, our results suggest that individual components of the tea had antiviral activities against the influenza A/PR/8/34 virus. Adlay tea inhibited multiplication of the H1N1, H3N2 and B types of influenza virus, including oseltamivir‐resistant viruses. In addition, adlay tea inhibited influenza infection during the periods of virus adsorption to the cell and virus replication. Adlay tea did not suppress hemagglutination inhibition or cell fusion, although it slightly inhibited virus binding to Malin Darby canine kidney cells. Furthermore, our findings suggest that the antiviral compounds included in adlay tea were ingredients other than polyphenols and that there were several types of effective compounds in adlay tea inhibiting several steps of viral replication.CONCLUSIONThe results of the present study demonstrate that adlay tea had antiviral effects against influenza viruses. Our findings with respect to adlay tea suggest that the polyphenols might have a small influence on its antiviral activity and that other ingredients might have more influence. © 2017 Society of Chemical Industry
Using repeated 137Cs and 210Pbex measurements to establish sediment budgets for different time windows and explore the effect of connectivity on soil erosion rates in a small experimental catchment in Southern Italy
Authors: Porto Paolo , Walling Desmond E. , Callegari Giovanni 
Published: September 2017

AbstractOver the last 50 years, different approaches have been employed in order to predict environmental risk due to soil erosion and to propose effective strategies to control erosion and sedimentation. The use of fallout radionuclides, mainly caesium‐137 (137Cs) and excess lead‐210 (210Pbex), has proved to be a very effective complement to existing traditional methods, especially if a resampling strategy is employed. The resampling approach involves repeating soil sampling and radionuclide measurements within the same site, after a known amount of time (generally 10 to 15 years). This strategy, in the light of the possibility to obtain independent estimates of soil erosion for different periods, makes it possible to establish sediment budgets for different time windows. The use of sediment budgets represents an important tool for providing information on catchment behaviour regarding the relationship between the sediment output at the catchment outlet and rates of sediment redistribution within the catchment. For this reason, this approach can provide important indications of possible changes of sediment connectivity at the catchment scale. The study reported here focuses on the W1 catchment (1.47 ha), located in Calabria, Southern Italy, for which long‐term measurements of sediment yield are also available. The W1 catchment supports a rangeland vegetation cover, and no change in land use occurred during the last 100 years. The catchment was sampled for 137Cs and 210Pbex analyses in 2001 and resampled in 2014 to provide estimates of soil erosion and deposition for different time windows. The uncertainty associated with these estimates is also discussed, and some guidelines for the application of 210Pbex as a soil erosion tracer are provided. The results provided by the measurements of sediment yield at the catchment outlet provide evidence of a general increase of soil erosion rates during the last 15–20 years. The estimates of sediment redistribution provided by the measurements of 210Pbex demonstrated that these results reflect an increase in the sediment delivery ratio and also emphasized how the presence of some small depositional areas associated with the occurrence of high‐magnitude events influences the change in sediment connectivity at the catchment scale.
Ice duration drives winter nitrate accumulation in north temperate lakes
Authors: Powers S. M. , Labou S. G. , Baulch H. M. , Hunt R. J. , Lottig N. R. , Hampton S. E. , Stanley E. H. 
Published: September 2017

AbstractThe duration of winter ice cover on lakes varies substantially with climate variability, and has decreased over the last several decades in many temperate lakes. However, little is known of how changes in seasonal ice cover may affect biogeochemical processes under ice. We examined winter nitrogen (N) dynamics under ice using a 30+ yr dataset from five oligotrophic/mesotrophic north temperate lakes to determine how changes in inorganic N species varied with ice duration. Nitrate accumulated during winter and was strongly related to the number of days since ice‐on. Exogenous inputs accounted for less than 3% of nitrate accumulation in four of the five lakes, suggesting a paramount role of nitrification in regulating N transformation and the timing of chemical conditions under ice. Winter nitrate accumulation rates ranged from 0.15 μg N L−1 d−1 to 2.7 μg N L−1 d−1 (0.011–0.19 μM d−1), and the mean for intermediate depths was 0.94 μg N L−1 d−1 (0.067 μM d−1). Given that winters with shorter ice duration (< 120 d) have become more frequent in these lakes since the late 1990s, peak winter nitrate concentrations and cumulative nitrate production under ice may be declining. As ice extent and duration change, the physical and chemical conditions supporting life will shift. This research suggests we may expect changes in the form and amount of inorganic N, and altered dissolved nitrogen : phosphorus ratios, in lakes during winters with shorter ice duration.
Surface Modification of Electrospun TPU Nanofiber Scaffold with CNF Particles by Ultrasound‐Assisted Technique for Tissue Engineering
Authors: Ye Jianhua , Si Junhui , Cui Zhixiang , Wang Qianting , Peng Kaiping , Chen Wenzhe , Peng Xiangfang , Chen Shia‐Chung 
Published: September 2017

AbstractA straightforward, fast, and versatile technique is developed to fabricate nanofibrous scaffold with excellent hydrophilicity, mechanical properties, and biocompatibility for tissue engineering. The thermoplastic polyurethane (TPU) nanofiber is fabricated by utilizing electrospinning, and then its surface is modified through simply immersing it into cellulose nanofibrils (CNF) dispersion and subjecting to ultrasonication. The results show that the CNF particles are successfully absorbed on the surface of TPU nanofiber. By introducing CNF particles on the surface of TPU nanofiber, the hydrophilicity, mechanical properties of fabricated CNF‐absorbed TPU scaffold are significantly increased. Additionally, the adhesion and proliferation of human umbilical vein endothelial cells cultured on CNF‐absorbed TPU scaffold are prominently enhanced in comparison with those of cultured on TPU scaffold. These findings suggest that the ultrasound‐assisted technique opens up a new way to simply and effectively modify the surface of various scaffolds and the modified scaffold could be shown a great potential in tissue engineering.
Aspartate tightens the anchoring of staphylococcal lipoproteins to the cytoplasmic membrane
Authors: Kumari Nimerta , Götz Friedrich , Nguyen Minh‐Thu 
Published: September 2017

AbstractIn gram‐negative bacteria, the ABC transporter LolCDE complex translocates outer membrane‐specific lipoproteins (Lpp) from the inner membrane to the outer membrane. Lpp possessing aspartate (Asp) at position +2 are not translocated because it functions as a LolCDE avoidance signal. In gram‐positive bacteria, lacking an outer membrane and the Lol system, Lpp are only anchored at the outer leaflet of the cytoplasmic membrane. However, the release of Lpp particularly in pathogenic or commensal species is crucial for immune modulation. Here, we provide evidence that in Staphylococcus aureus Asp at position +2 plays a role in withholding Lpp to the cytoplasmic membrane. Screening of published exoproteomic data of S. aureus revealed that Lpp mainly with Gly or Ser at position +2 were found in exoproteome, but there was no Lpp with Asp+2. The occurrence of Lpp with Asp+2 is infrequent in gram‐positive bacteria. In S. aureus USA300 only seven of the 67 Lpp possess Asp+2; among them five Lpp represented Lpl lipoproteins involved in host cell invasion. Our study demonstrated that replacing the Asp+2 present in Lpl8 with a Ser enhances its release into the supernatant. However, there is no different release of Asp+2 and Ser+2 in mprF mutant that lacks the positive charge of lysyl‐phosphatidylglycerol (Lys‐PG). Moreover, substitution of Ser+2 by Asp in SitC (MntC) did not lead to a decreased release indicating that in staphylococci positions +3 and +4 might also be important for a tighter anchoring of Lpp. Here, we show that Asp in position +2 and adjacent amino acids contribute in tightening the anchoring of Lpp by interaction of the negative charged Asp with the positive charged Lys‐PG.
Biologically active quinoline and quinazoline alkaloids part I
Authors: Shang Xiao‐Fei , Morris‐Natschke Susan L. , Liu Ying‐Qian , Guo Xiao , Xu Xiao‐Shan , Goto Masuo , Li Jun‐Cai , Yang Guan‐Zhou , Lee Kuo‐Hsiung 
Published: September 2017

AbstractQuinoline and quinazoline alkaloids, two important classes ofN‐based heterocyclic compounds, have attracted tremendous attention from researchers worldwide since the 19th century. Over the past 200 years, many compounds from these two classes were isolated from natural sources, and most of them and their modified analogs possess significant bioactivities. Quinine and camptothecin are two of the most famous and important quinoline alkaloids, and their discoveries opened new areas in antimalarial and anticancer drug development, respectively. In this review, we survey the literature on bioactive alkaloids from these two classes and highlight research achievements prior to the year 2008 (Part I). Over 200 molecules with a broad range of bioactivities, including antitumor, antimalarial, antibacterial and antifungal, antiparasitic and insecticidal, antiviral, antiplatelet, anti‐inflammatory, herbicidal, antioxidant and other activities, were reviewed. This survey should provide new clues or possibilities for the discovery of new and better drugs from the original naturally occurring quinoline and quinazoline alkaloids.
Dual‐rotation C‐arm cone‐beam computed tomography to increase low‐contrast detection
Authors: Reshef Aymeric , Riddell Cyril , Trousset Yves , Ladjal Saïd , Bloch Isabelle 
Published: September 2017

PurposeThis paper investigates the capabilities of a dual‐rotation C‐arm cone‐beam computed tomography (CBCT) framework to improve non‐contrast‐enhanced low‐contrast detection for full volume or volume‐of‐interest (VOI) brain imaging.MethodThe idea is to associate two C‐arm short‐scan rotational acquisitions (spins): one over the full detector field of view (FOV) at low dose, and one collimated to deliver a higher dose to the central densest parts of the head. The angular sampling performed by each spin is allowed to vary in terms of number of views and angular positions. Collimated data is truncated and does not contain measurement of the incoming X‐ray intensities in air (air calibration). When targeting full volume reconstruction, the method is intended to act as a virtual bow‐tie. When targeting VOI imaging, the method is intended to provide the minimum full detector FOV data that sufficiently corrects for truncation artifacts. A single dedicated iterative algorithm is described that handles all proposed sampling configurations despite truncation and absence of air calibration.ResultsFull volume reconstruction of dual‐rotation simulations and phantom acquisitions are shown to have increased low‐contrast detection for less dose, with respect to a single‐rotation acquisition. High CNR values were obtained on 1% inserts of the Catphan 515 module in 0.94 mm thick slices. Image quality for VOI imaging was preserved from truncation artifacts even with less than 10 non‐truncated views, without using the sparsity a priori common to such context.ConclusionA flexible dual‐rotation acquisition and reconstruction framework is proposed that has the potential to improve low‐contrast detection in clinical C‐arm brain soft‐tissue imaging.
Assessment of the spectral performance of hybrid photon counting x‐ray detectors
Authors: Trueb Peter , Zambon Pietro , Broennimann Christian 
Published: September 2017

PurposeHybrid Photon Counting (HPC) detectors profoundly improved x‐ray diffraction experiments at third generation synchrotron facilities. Enabling the simultaneous measurement of x‐ray intensities in multiple energy bins, they also have many potential applications in the field of medical imaging. A prerequisite for this is a clean spectral response. To quantify how efficiently HPC detectors are able to assign photons to the correct energy bin, a quantity called Spectral Efficiency (SE) is introduced. This figure of merit measures the number of x‐rays with correctly assigned energy normalized to the number of incoming photons.MethodsA prototype HPC detector has been used to perform precision measurements of x‐ray spectra at the BESSY synchrotron. The detector consists of a novel ASIC with pixels of 75 × 75 μm2 size and a 750 μm thick CdTe sensor. The experimental data are complemented by the results of a Monte‐Carlo (MC) simulation, which not only includes the physical detection process but also pulse pile‐up at high photon fluxes. The spectra and the measured photon flux are used to infer the Spectral Efficiency.ResultsIn the energy range from 10 to 60 keV, both the Quantum Efficiency and the Spectral Efficiency were precisely measured and simulated. Good agreement between simulation and experiment has been achieved. For the small pixels of the prototype detector, a SE between 15% and 77% has been determined. The MC simulation is used to predict the SE for various pixel sizes at different photon fluxes. For a typical flux of 5∙107 photons/mm2/s used in human Computed Tomography (CT), the highest SE is achieved for pixel sizes in the range between 150 × 150 μm2 and 300 × 300 μm2.ConclusionsThe Spectral Efficiency turns out to be a useful figure of merit to quantify the spectral performance of HPC detectors. It allows a quantitative comparison of detectors with different sensor and ASIC configurations over a broad range of x‐ray energies and fluxes. The maximization of the SE is a prerequisite for a successful usage of HPC detectors in the field of medical imaging.