bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytomorphological and nitrogen metabolic enzyme analysis of psychrophilic and mesophilic Nostoc sp.: a comparative outlook
Authors: Thangaraj Bhuvaneshwari , Rajasekar Diana Princey , Vijayaraghavan Rashmi , Garlapati Deviram , Devanesan Arul Ananth , Lakshmanan Uma , Dharmar Prabaharan 
Published: May 2017

Abstract
Cyanobacterial diazotrophs play a significant role in environmental nitrogen economy despite their habitat either tropical or polar. However, the phenomenon by which it copes with temperature induced stress is poorly understood. Temperature response study of psychrophilic and mesophilic Nostoc strains explores their adaptive mechanisms. The selected psychrophilic and mesophilic strains were confirmed as Nostoc punctiforme and Nostoc calcicola respectively, by ultrastructure and 16S rDNA phylogeny. The psychrophilic strain has extensive glycolipid and polysaccharide sheath along with characteristic deposition of cyanophycin, polyhydroxybutyrate granules, and carboxysomes. This is possibly an adaptive strategy exhibited to withstand the freezing temperature and high intense of ultraviolet rays. The biomass measured in terms of dry weight, protein, and chlorophyll indicated a temperature dependant shift in both the psychrophilic and mesophilic strains and attained maximum growth in their respective temperature niches. At low temperature, psychrophilic organism exhibited nitrogenase activity, while mesophilic strains did not. The maximum glutamine synthetase activity was observed at 4 °C for psychrophilic and 37 °C for mesophilic strains. Activity at 4 °C in psychrophilic strains revealed their energetic mechanism even at low temperature. The nitrate and nitrite reductase of both psychrophilic and mesophilic strains showed maximum activity at 37 °C denoting their similar nitrogen assimilating mechanisms for combined nitrogen utilization. The activity studies of nitrogen fixation/assimilation enzymes have differential effects at varying temperatures, which provide valuable insights of physiological contribution and role of Nostoc strains in the biological nitrogen cycle.
Production of biodiesel from microalgae through biological carbon capture: a review
Authors: Mondal Madhumanti , Goswami Shrayanti , Ghosh Ashmita , Oinam Gunapati , Tiwari O. N. , Das Papita , Gayen K. , Mandal M. K. , Halder G. N. 
Published: May 2017

AbstractGradual increase in concentration of carbon dioxide (CO2) in the atmosphere due to the various anthropogenic interventions leading to significant alteration in the global carbon cycle has been a subject of worldwide attention and matter of potential research over the last few decades. In these alarming scenario microalgae seems to be an attractive medium for capturing the excess CO2present in the atmosphere generated from different sources such as power plants, automobiles, volcanic eruption, decomposition of organic matters and forest fires. This captured CO2through microalgae could be used as potential carbon source to produce lipids for the generation of biofuel for replacing petroleum-derived transport fuel without affecting the supply of food and crops. This comprehensive review strives to provide a systematic account of recent developments in the field of biological carbon capture through microalgae for its utilization towards the generation of biodiesel highlighting the significance of certain key parameters such as selection of efficient strain, microalgal metabolism, cultivation systems (open and closed) and biomass production along with the national and international biodiesel specifications and properties. The potential use of photobioreactors for biodiesel production under the influence of various factors viz., light intensity, pH, time, temperature, CO2concentration and flow rate has been discussed. The review also provides an economic overview and future outlook on biodiesel production from microalgae.
Biosorption and equilibrium isotherms study of cadmium removal by Nostoc muscorum Meg 1: morphological, physiological and biochemical alterations
Authors: Ahad Rabbul Ibne A. , Goswami Smita , Syiem Mayashree B. 
Published: May 2017

AbstractRice fields of Meghalaya especially in the coal mining belt receive water contaminated by effluents from mines that are known to carry harmful heavy metal ions such as Cu, Fe, Zn, Ni, Cd, As, Pb, Cr, etc. Cd exposure was analyzed in the cyanobacteriumNostoc muscorumMeg 1 isolated from a contaminated rice field in Sohra, Meghalaya, India. Toxicity study established 0.5 ppm on day 3 to be the LD50. At LD50chlorophyllaand total protein concentration was reduced by 50.9 and 52.5%, while nitrogenase and glutamine synthetase activities were inhibited by 40.8 and 38.4%. EDX and FTIR analyses confirmed Cd binding and participation of hydroxyl, carbonyl, carboxyl and phosphate groups in biosorption of Cd onto the cell surfaces. SEM study established morphological changes. At pH 8.0 and temperature 25 ± 2 °C, the cyanobacterium removed 92% Cd within 24 h. Of this, 91% Cd was adsorbed on the cell surface while 4% was internally accumulated. The energy required for internal accumulation of Cd was partly provided in the form of ATP synthesized during active photosynthesis. The Langmuir isotherm was found best fitted with aR2value 0.98 when compared to Freundlich and Temkin adsorption isotherms. The maximum sorption capacity,Qmax,of the organism was 71.4 mg of Cd per g of biomass.RLvalue of 0.29 indicated favorable interaction between cyanobacterial biomass and Cd. The adsorption intensity,nvalue 7.69 g/L obtained from Freundlich isotherm showed that the organism possessed high Cd sorption capacity.
Comparaciones entre más de dos grupos: aportes para el cálculo del tamaño del efecto
Authors: Caycho-Rodríguez Tomás 
Published: May 2017

Glaría et al., estudiaron la existencia de diferencias de burnout y engagement de acuerdo a diferentes niveles de formación en fonoaudiología mediante el test de significación de la hipótesis nula (NHST) asociado al valor coeficiente ANOVA de un factor. Los resultados señalan la existencia de diferencias estadísticamente significativas en el agotamiento emocional (AE) (p < 0.001) y despersonalización (D) (p < 0.05); mientras que los estudiantes de cuarto año, en comparación con los otros, presentaban un nivel significativamente superior de AE y en D superaban solo a los de segundo año.
The South African Constitutional Court: Upholding the Rule of Law and the Separation of Powers
Authors: Parpworth Neil 
Published: May 2017

AbstractThe supremacy of the constitution and the rule of law are key features of the post-apartheid legal order in South Africa. For either to have any real value, however, it is necessary that they are interpreted and applied by an independent judiciary that is free from executive influence. This important task has fallen mainly on the Constitutional Court. It has recently been called upon to rule on the lawfulness of the conduct of both the president and the National Assembly and held that both had acted unlawfully and inconsistently with the constitution. In the author's view, this ruling signifies that the maturing court is fully aware of its own constitutional obligations and that, unlike its apartheid era predecessors that were hamstrung by the supremacy of Parliament, it possesses a mandate to check the abuse of power by other branches of government.
Geographically disjunct phylogenetic lineages inLeptogium hibernicumrevealLeptogium krogiaesp. nov. from East Africa
Authors: BJELLAND Torbjørg , BENDIKSBY Mika , FRISCH Andreas 
Published: May 2017

AbstractPhylogenetic analyses of nuclear (Mcm7, nrITS, nrLSU) and mitochondrial (mrSSU) DNA sequences revealed geographically disjunct lineages inLeptogium hibernicum. One of these lineages is described here asLeptogium krogiae, which differs fromL. hibernicumin the thinner thallus (190–210 µm vs. 390–480 µm), shallowly striate lobes instead of deeply furrowed lobes, isidia that are seldom distinctly flattened, and apothecia with a subhymenial euparaplectenchymatous layer.Leptogium krogiaeis a widespread epiphyte in mist-affected woodlands and montane forests in East Africa and appears to be a common species.
The genus Relicinopsis is nested within Relicina (Parmeliaceae, Ascomycota)
Authors: KIRIKA Paul M. , DIVAKAR Pradeep K. , LEAVITT Steven D. , BUARUANG Kawinnat , CRESPO Ana , MUGAMBI George , GATHERI Grace W. , LUMBSCH H. Thorsten 
Published: May 2017

AbstractMacro-morphological features traditionally used to segregate genera in Parmeliaceae have been shown to be highly plastic, placing limits on their taxonomic value. Here we aim to elucidate the evolutionary relationships of the genera Relicina and Relicinopsis and reassess the phenotypic features traditionally used to separate these genera. To this end, we gathered ribosomal DNA sequences of ITS, nuLSU and mtSSU and analyzed them in a phylogenetic framework. Relicina was recovered as paraphyletic, with Relicinopsis nested within, and three different clades were identified within Relicina. Alternative hypothesis tests significantly rejected the monophyly of Relicina. Our results indicate that the presence or absence of bulbate cilia is of limited taxonomic value in this clade. Based on differences in conidia, however, we propose to accept Relicinopsis as a subgenus within Relicina as Relicina subgen. Relicinopsis (Elix & Verdon) Kirika, Divakar & Lumbsch. It is proposed that five new combinations of species previously classified in Relicinopsis be placed in Relicina.
ELM-KNN for photometric redshift estimation of quasars
Authors: Zhang Yanxia , Tu Yang , Zhao Yongheng , Tian Haijun 
Published: May 2017

AbstractWe explore photometric redshift estimation of quasars with the SDSS DR12 quasar sample. Firstly the quasar sample is separated into three parts according to different redshift ranges. Then three classifiers based on Extreme Learning Machine (ELM) are created in the three redshift ranges. Finally k-Nearest Neighbor (kNN) approach is applied on the three samples to predict photometric redshifts of quasars with multiwavelength photometric data. We compare the performance with different input patterns by ELM-KNN with that only by kNN. The experimental results show that ELM-KNN is feasible and superior to kNN (e.g. rms is 0.0751 vs. 0.2626 for SDSS sample), in other words, the ensemble method has the potential to increase regressor performance beyond the level reached by an individual regressor alone and will be a good choice when facing much more complex data.
The search of radio transients in the RATAN-600 radio telescope surveys
Authors: Zhelenkova Olga P. , Majorova Elena K. 
Published: May 2017

AbstractWe present the results of the search of variable sources and transient events in the archive data of the sky surveys conducted on 3.9 GHz on the RATAN-600 radio telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) in 1980-1994. 17% of the total studied sources can be attributed to the variables in radio range. About half of them has significant variations in optical brightness according to the data of the catalogs. At the level of 3-5 r.m.s. we found three transient events. Two weak events probably associated with AGN activities or with cataclysmic events such as GRB and a supernova flash. The nature of the third event has not been established. According to our estimation the surface density of radio transients is 0.03 on one square angular degree with the detection level 8–11 mJy on 3.94 GHz.
Data Management in the Euclid Science Archive System
Authors: de Teodoro P. , Nieto S. , Altieri B. 
Published: May 2017

AbstractEuclid is the ESA M2 mission and a milestone in the understanding of the geometry of the Universe. In total Euclid will produce up to 26 PB per year of observations. The Science Archive Systems (SAS) belongs to the Euclid Archive System (EAS) that sits in the core of the Euclid Science Ground Segment (SGS). The SAS is being built at the ESAC Science Data Centre (ESDC), which is responsible for the development and operations of the scientific archives for the Astronomy, Planetary and Heliophysics missions of ESA. The SAS is focused on the needs of the scientific community and is intended to provide access to the most valuable scientific metadata from the Euclid mission. In this paper we describe the architectural design of the system, implementation progress and the main challenges from the data management point of view in the building of the SAS.
Prototype-based Models for the Supervised Learning of Classification Schemes
Authors: Biehl Michael , Hammer Barbara , Villmann Thomas 
Published: May 2017

AbstractAn introduction is given to the use of prototype-based models in supervised machine learning. The main concept of the framework is to represent previously observed data in terms of so-called prototypes, which reflect typical properties of the data. Together with a suitable, discriminative distance or dissimilarity measure, prototypes can be used for the classification of complex, possibly high-dimensional data. We illustrate the framework in terms of the popular Learning Vector Quantization (LVQ). Most frequently, standard Euclidean distance is employed as a distance measure. We discuss how LVQ can be equipped with more general dissimilarites. Moreover, we introduce relevance learning as a tool for the data-driven optimization of parameterized distances.
Dealing with Uncertain Multimodal Photometric Redshift Estimations
Authors: Polsterer Kai L. 
Published: May 2017

AbstractDue to limitations in available instrumentation and observation time, a spectroscopic determination of distance is not feasible for all objects in the sky. Therefore statistical methods that estimate redshifts, based on photometric measurement are of tremendous importance to many astrophysical questions. Determining cosmological parameters and understanding evolutionary processes in the universe are just two examples. When perform astrophysical analyses, it is necessary to treat the uncertainties of the estimates correctly. Over-simplification of results and the usage of wrong tools to evaluate the performance of probabilistic redshift estimates were commonly found in the literature. We present proper tools for evaluating uncertain redshift estimates and discuss the necessity of multimodal redshift distributions.
Optical light curves of FUor and FUor-like objects
Authors: Semkov Evgeni , Peneva Stoyanka , Ibryamov Sunay 
Published: May 2017

AbstractUsing recent data from photometric monitoring and data from the photographic plate archives we aim to study, the long-term photometric behavior of FUors. The construction of the historical light curves of FUors could be very important for determining the beginning of the outburst, the time to reach the maximum light, the rate of increase and decrease in brightness, the pre-outburst variability of the star. Our CCD photometric observations were performed with the telescopes of the Rozhen (Bulgaria) and Skinakas (Crete, Greece) observatories. Most suitable for long-term photometric study are the plate archives of the big Schmidt telescopes, as the telescopes at Kiso Observatory, Asiago Observatory, Palomar Observatory and others. In comparing our results with light curves of the well-studied FUors, we conclude that every new FUor object shows different photometric behavior. Each known FUor has a different rate of increase and decrease in brightness and a different light curve shape.
Target and (Astro-)WISE technologies Data federations and its applications
Authors: Valentijn E. A. , Begeman K. , Belikov A. , Boxhoorn D. R. , Brinchmann J. , McFarland J. , Holties H. , Kuijken K. H. , Kleijn G. Verdoes , Vriend W-J. , Williams O. R. , Roerdink J. B. T. M. , Schomaker L. R. B. , Swertz M. A. , Tsyganov A. , van Dijk G. J. W. 
Published: May 2017

AbstractAfter its first implementation in 2003 the Astro-WISE technology has been rolled out in several European countries and is used for the production of the KiDS survey data. In the multi-disciplinary Target initiative this technology, nicknamed WISE technology, has been further applied to a large number of projects. Here, we highlight the data handling of other astronomical applications, such as VLT-MUSE and LOFAR, together with some non-astronomical applications such as the medical projects Lifelines and GLIMPS; the MONK handwritten text recognition system; and business applications, by amongst others, the Target Holding.We describe some of the most important lessons learned and describe the application of the data-centric WISE type of approach to the Science Ground Segment of the Euclid satellite.
The changing landscape of astrostatistics and astroinformatics
Authors: Feigelson Eric D. 
Published: May 2017

AbstractThe history and current status of the cross-disciplinary fields of astrostatistics and astroinformatics are reviewed. Astronomers need a wide range of statistical methods for both data reduction and science analysis. With the proliferation of high-throughput telescopes, efficient large scale computational methods are also becoming essential. However, astronomers receive only weak training in these fields during their formal education. Interest in the fields is rapidly growing with conferences organized by scholarly societies, textbooks and tutorial workshops, and research studies pushing the frontiers of methodology. R, the premier language of statistical computing, can provide an important software environment for the incorporation of advanced statistical and computational methodology into the astronomical community.
Overcoming the crystallization and designability issues in the ultrastable zirconium phosphonate framework system
Authors: Zheng Tao , Yang Zaixing , Gui Daxiang , Liu Zhiyong , Wang Xiangxiang , Dai Xing , Liu Shengtang , Zhang Linjuan , Gao Yang , Chen Lanhua , Sheng Daopeng , Wang Yanlong , Diwu Juan , Wang Jianqiang , Zhou Ruhong , Chai Zhifang , Albrecht-Schmitt Thomas E. , Wang Shuao 
Published: May 2017

AbstractMetal-organic frameworks (MOFs) based on zirconium phosphonates exhibit superior chemical stability suitable for applications under harsh conditions. These compounds mostly exist as poorly crystallized precipitates, and precise structural information has therefore remained elusive. Furthermore, a zero-dimensional zirconium phosphonate cluster acting as secondary building unit has been lacking, leading to poor designability in this system. Herein, we overcome these challenges and obtain single crystals of three zirconium phosphonates that are suitable for structural analysis. These compounds are built by previously unknown isolated zirconium phosphonate clusters and exhibit combined high porosity and ultrastability even in fuming acids. SZ-2 possesses the largest void volume recorded in zirconium phosphonates and SZ-3 represents the most porous crystalline zirconium phosphonate and the only porous MOF material reported to survive in aqua regia. SZ-2 and SZ-3 can effectively remove uranyl ions from aqueous solutions over a wide pH range, and we have elucidated the removal mechanism.
A-kinase anchoring protein BIG3 coordinates oestrogen signalling in breast cancer cells
Authors: Yoshimaru Tetsuro , Ono Masaya , Bando Yoshimi , Chen Yi-An , Mizuguchi Kenji , Shima Hiroshi , Komatsu Masato , Imoto Issei , Izumi Keisuke , Honda Junko , Miyoshi Yasuo , Sasa Mitsunori , Katagiri Toyomasa 
Published: May 2017

AbstractApproximately 70% of breast cancer cells express oestrogen receptor alpha (ERα). Previous studies have shown that the Brefeldin A-inhibited guanine nucleotide-exchange protein 3–prohibitin 2 (BIG3-PHB2) complex has a crucial role in these cells. However, it remains unclear how BIG3 regulates the suppressive activity of PHB2. Here we demonstrate that BIG3 functions as an A-kinase anchoring protein that binds protein kinase A (PKA) and the α isoform of the catalytic subunit of protein phosphatase 1 (PP1Cα), thereby dephosphorylating and inactivating PHB2. E2-induced PKA-mediated phosphorylation of BIG3-S305 and -S1208 serves to enhance PP1Cα activity, resulting in E2/ERα signalling activation via PHB2 inactivation due to PHB2-S39 dephosphorylation. Furthermore, an analysis of independent cohorts of ERα-positive breast cancers patients reveal that both BIG3 overexpression and PHB2-S39 dephosphorylation are strongly associated with poor prognosis. This is the first demonstration of the mechanism of E2/ERα signalling activation via the BIG3–PKA–PP1Cα tri-complex in breast cancer cells.
Hydrodynamic cavitation in Stokes flow of anisotropic fluids
Authors: Stieger Tillmann , Agha Hakam , Schoen Martin , Mazza Marco G. , Sengupta Anupam 
Published: May 2017

AbstractCavitation, the nucleation of vapour in liquids, is ubiquitous in fluid dynamics, and is often implicated in a myriad of industrial and biomedical applications. Although extensively studied in isotropic liquids, corresponding investigations in anisotropic liquids are largely lacking. Here, by combining liquid crystal microfluidic experiments, nonequilibrium molecular dynamics simulations and theoretical arguments, we report flow-induced cavitation in an anisotropic fluid. The cavitation domain nucleates due to sudden pressure drop upon flow past a cylindrical obstacle within a microchannel. For an anisotropic fluid, the inception and growth of the cavitation domain ensued in the Stokes regime, while no cavitation was observed in isotropic liquids flowing under similar hydrodynamic parameters. Using simulations we identify a critical value of the Reynolds number for cavitation inception that scales inversely with the order parameter of the fluid. Strikingly, the critical Reynolds number for anisotropic fluids can be 50% lower than that of isotropic fluids.
Pyk2 modulates hippocampal excitatory synapses and contributes to cognitive deficits in a Huntington’s disease model
Authors: Giralt Albert , Brito Veronica , Chevy Quentin , Simonnet Clémence , Otsu Yo , Cifuentes-Díaz Carmen , de Pins Benoit , Coura Renata , Alberch Jordi , Ginés Sílvia , Poncer Jean-Christophe , Girault Jean-Antoine 
Published: May 2017

AbstractThe structure and function of spines and excitatory synapses are under the dynamic control of multiple signalling networks. Although tyrosine phosphorylation is involved, its regulation and importance are not well understood. Here we study the role of Pyk2, a non-receptor calcium-dependent protein-tyrosine kinase highly expressed in the hippocampus. Hippocampal-related learning and CA1 long-term potentiation are severely impaired in Pyk2-deficient mice and are associated with alterations in NMDA receptors, PSD-95 and dendritic spines. In cultured hippocampal neurons, Pyk2 has autophosphorylation-dependent and -independent roles in determining PSD-95 enrichment and spines density. Pyk2 levels are decreased in the hippocampus of individuals with Huntington and in the R6/1 mouse model of the disease. Normalizing Pyk2 levels in the hippocampus of R6/1 mice rescues memory deficits, spines pathology and PSD-95 localization. Our results reveal a role for Pyk2 in spine structure and synaptic function, and suggest that its deficit contributes to Huntington’s disease cognitive impairments.