bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the potential of δ18O and δ15N to assess N2O reduction to N2 in soil
Authors: Decock C. , Six J. 
Published: July 2013

SummaryEnhancing microbial reduction of the potent greenhouse gas nitrous oxide (N2O) to N2 could be a promising strategy to mitigate emissions from soils, but N2O reduction rates are currently neither well understood nor quantified. It has been suggested that the importance of N2O reduction to N2 could be estimated from relationships between δ18O and δ15N when N2O production and reduction occur simultaneously. We assessed the robustness of such relationships by using simple simulation models and experimental data for various scenarios, including open versus closed system isotope dynamics and collection of N2O fluxes over time with and without refreshing the headspace between sampling. We found that relationships between δ18O and δ15N vary dramatically with experimental conditions (such as headspace gas concentration and sampling scheme) and open versus closed system isotope dynamics, irrespective of N2O reduction rate. Therefore, we conclude that the simple relationships between δ18O and δ15N currently used are not robust indicators of N2O reduction to N2 and strongly discourage graphical interpretations of δ18O and δ15N to determine N2O reduction. We recommend the development of more advanced process‐based isotope models that take into account open versus closed system isotope dynamics, experimental conditions, isotope values of precursors and other biogeochemical controls on δ15N and δ18O of N2O to estimate N2O reduction rates more reliably from natural abundance isotope values of N2O.
Adoption of lycaenid Niphanda fusca (Lepidoptera: Lycaenidae) caterpillars by the host ant Camponotus japonicus (Hymenoptera: Formicidae)
Authors: Hojo Masaru K. , Yamaguchi Susumu , Akino Toshiharu , Yamaoka Ryohei 
Published: July 2013

AbstractCaterpillars of the parasitic lycaenid butterfly are often adopted by host ants. It has been proposed that this adoption occurs because the caterpillars mimic the cuticular hydrocarbons of the host ant. This study aimed to examine whether caterpillars of the Japanese lycaenid butterfly Niphanda fusca induce adoption by mimicking their host ant Camponotus japonicus. Behavioral observations conducted in the laboratory showed that most second‐instar caterpillars were not adopted, whereas most third‐instar caterpillars were successfully adopted by host workers. A chemical comparison detected no characteristic differences in the cuticular hydrocarbon profiles between second‐ and third‐instar caterpillars. However, morphological features of the caterpillars differed between the second and third instars; third‐instar caterpillars developed exocrine glands (ant organs) such as tentacle organs and a dorsal nectary organ. These results suggest that multiple chemical signatures, not only cuticular hydrocarbons, may be important for invasion of the host ant nest.
Effects of environmental factors on the species composition of aquatic insects in irrigation ponds
Authors: Nakanishi Kosuke , Nishida Takayoshi , Kon Masahiro , Sawada Hiroichi 
Published: July 2013

AbstractAlthough irrigation ponds contribute to the conservation of aquatic biodiversity, they have experienced declines in recent years. We therefore examined the relationships between various environmental factors and the community composition of aquatic insects, specifically insect predators, in irrigation ponds to gain knowledge that would aid in the conservation and restoration of biodiversity. We selected Odonata, Hemiptera and Coleoptera as target taxonomic groups and conducted censuses of these groups in 21 ponds in Shiga, central Japan. In total, we collected 30 and 10 species (or species groups) of Odonata and Hemiptera, respectively, and 17 species of Coleoptera. A partial canonical correspondence analysis revealed that the following four environmental factors significantly affected the species composition of aquatic insect communities: the number of emergent plant species, percent concrete revetment, presence of litter and peripheral length. Among these variables, the number of emergent plant species was the most potent factor, perhaps because emergent plants serve as sites for oviposition and emergence, and provide refugia for aquatic insects (odonate nymphs in particular). In contrast, some species specifically inhabited sites poor in emergent plants. This study shows that reductions in concrete revetments are necessary for the conservation of biodiversity. This would lead to increases in the number of aquatic plant species, which provide habitats and oviposition sites for many aquatic insects. Furthermore, to enrich the local biodiversity of aquatic insects, groups of irrigation ponds with different environments are needed.
Upregulation of heat shock protein 27 confers resistance to actinomycin D‐induced apoptosis in cancer cells
Authors: Ma Wenbo , Teng Yan , Hua Hui , Hou Jinlin , Luo Ting , Jiang Yangfu 
Published: July 2013

Actinomycin D (Act D) is a general transcriptional inhibitor that is approved for the treatment of sarcomas, and Wilms, germ cell and trophoblastic tumors. Little is known about the molecular mechanisms that dictate the sensitivity of cancer cells to Act D. In this study, we investigated the effects of Act D on heat shock proteins (HSPs) and the expression and roles of HSP27 in Act D‐induced cancer cell apoptosis. We show that Act D upregulates HSP27 and HSP70 expression in cancer cells, whereas it inhibits HSP90 expression. The upregulation of HSP27 by Act D is not attributable to changes in HSP27 transcription or HSP27 synthesis. HSP27 knockdown leads to an increase in Act D‐induced caspase 3 and caspase 7 cleavage, and sensitizes rhabdosarcoma cells and breast cancer cells to Act D‐induced apoptosis. We conclude that upregulation of HSP27 represents an adaptive response that compromises the anticancer activity of Act D.
Diversification of NAD biological role : the importance of location
Authors: Di Stefano Michele , Conforti Laura 
Published: July 2013

Over 100 years after its first discovery, several new aspects of the biology of the redox co‐factor NAD are rapidly emerging. NAD, as well as its precursors, its derivatives, and its metabolic enzymes, have been recently shown to play a determinant role in a variety of biological functions, from the classical role in oxidative phosphorylation and redox reactions to a role in regulation of gene transcription, lifespan and cell death, from a role in neurotransmission to a role in axon degeneration, and from a function in regulation of glucose homeostasis to that of control of circadian rhythm. It is also becoming clear that this variety of specialized functions is regulated by the fine subcellular localization of NAD, its related nucleotides and its metabolic enzymatic machinery. Here we describe the known NAD biosynthetic and catabolic pathways, and review evidence supporting a specialized role for NAD metabolism in a subcellular compartment‐dependent manner.
Links between the recruitment success of northern European hake (Merluccius merluccius L.) and a regime shift on the NE Atlantic continental shelf
Authors: Goikoetxea Nerea , Irigoien Xabier 
Published: July 2013

AbstractThe distribution of northern European hake (Merluccius merluccius L.) extends from the Bay of Biscay up to Norwegian waters. However, despite its wide geographical distribution, there have been few studies on fluctuations in the European hake populations. Marine ecosystem shifts have been investigated worldwide and their influence on trophic levels has been studied, from top predator fish populations down to planktonic prey species, but there is little information on the effect of atmosphere–ocean shifts on European hake. This work analyses hake recruitment success (recruits per adult biomass) in relation to environmental changes over the period 1978–2006 in order to determine whether the regime shift identified in several abiotic and biotic variables in the North Sea also affected the Northeast Atlantic shelf oceanography. Hake recruitment success as well as parameters such as the sea surface temperature, wind patterns and copepod abundance changed significantly at the end of the 1980s, demonstrating an ecological regime shift in the Northeast Atlantic. Despite the low reproductive biomass recorded during the last decades, hake recruitment success has been higher since the change in 1989/90. The higher productivity may have sustained the population despite the intense fishing pressure; copepod abundance, warmer water temperatures and moderate eastward transport were found to be beneficial. In conclusion, in 1988/89 the Northeast Atlantic environment shifted to a favourable regime for northern hake production. This study supports the hypothesis that the hydro‐climatic regime shift that affected the North Sea in the late 1980s may have influenced a wider region, such as the Northeast Atlantic.
Higher Education Research in Asia: a Publication and Co‐Publication Analysis
Authors: Jung Jisun , Horta Hugo 
Published: July 2013

AbstractThis study explores higher education research in Asia. Drawing on scientometrics, the mapping of science and social network analysis, this paper examines the publications of 38 specialised journals on higher education over the past three decades. The findings indicate a growing number of higher education research publications but the proportion of Asian publications in relation to the total world publications in higher education research remains stationary. The higher education research community in Asia is heavily concentrated in a few countries and universities, resting on a relatively small number of core scholars who publish research in the international specialised higher education journals. In response to increasing challenges in Asian higher education systems, the paper suggests that the higher education research community in Asia needs to be expanded and include more regional and international collaborations
The Surveillance of Learning: A Critical Analysis of University Attendance Policies
Authors: Macfarlane Bruce 
Published: July 2013

AbstractUniversities have recently strengthened their class attendance policies along with associated practices that intensify the surveillance of learning: a series of administrative and pedagogic strategies that monitor the extent to which students conform with behavioural expectations associated with learning. Drawing on university policy statements, the paper identifies implicit arguments underpinning attendance requirements for students in higher education. These include demonstrating the accountability of publicly funded higher education, a concern for the pastoral and academic welfare of students and their appropriate preparation for expectations associated with workplace and professional practice. In a critique it is argued that attendance policies promote presenteeism as part of the discourse of learnerism. Such rules further infantilise students rather than developing their capacity to make informed choices as adults thereby failing to respect their academic freedom.
Physicochemical and mechanical properties of zirconium oxide and niobium oxide modified Portland cement‐based experimental endodontic sealers
Authors: Viapiana R. , Flumignan D. L. , Guerreiro‐Tanomaru J. M. , Camilleri J. , Tanomaru‐Filho M. 
Published: July 2013

AbstractAimTo evaluate the physicochemical and mechanical properties of Portland cement‐based experimental sealers (ES) with different radiopacifying agents (zirconium oxide and niobium oxide micro‐ and nanoparticles) in comparison with the following conventional sealers: AH Plus, MTA Fillapex and Sealapex.MethodologyThe materials were tested for setting time, compressive strength, flow, film thickness, radiopacity, solubility, dimensional stability and formaldehyde release. Data were subjected to anova and Tukey tests (P < 0.05).ResultsMTA Fillapex had the shortest setting time and lowest compressive strength values (P < 0.05) compared with the other materials. The ES had flow values similar to the conventional materials, but higher film thickness (P < 0.05) and lower radiopacity (P < 0.05). Similarly to AH Plus, the ES were associated with dimensional expansion (P > 0.05) and lower solubility when compared with MTA Fillapex and Sealapex (P < 0.05). None of the endodontic sealers evaluated released formaldehyde after mixing.ConclusionWith the exception of radiopacity, the Portland cement‐based experimental endodontic sealers presented physicochemical properties according to the specifications no 57 ANSI/ADA (ADA Professional Product Review, 2008) and ISO 6876 (Dentistry — Root Canal Sealing Materials, 2012, British Standards Institution, London, UK). The sealers had setting times and flow ability that was adequate for clinical use, satisfactory compressive strength and low solubility. Additional studies should be carried out with the purpose of decreasing the film thickness and to determine the ideal ratio of radiopacifying agents in Portland cement‐based root canal sealers.
Influence of the exposure of MTA with and without calcium chloride to phosphate‐buffered saline on the push‐out bond strength to dentine
Authors: de Almeida J. , Felippe M. C. S , Bortoluzzi E. A. , Teixeira C. S. , Felippe W. T. 
Published: July 2013

AbstractAimTo analyse the influence of exposure of mineral trioxide aggregate (MTA) with and without calcium chloride (CaCl2) to phosphate‐buffered saline (PBS) on the push‐out bond strength, over different experimental periods.MethodologyOne hundred and twenty dentine discs with standardized cavities were filled with MTA with and without 10% CaCl2. The specimens were randomly divided as follows (n = 30): (G1) MTA in contact with a moistened cotton pellet, (G2) MTA immersed in PBS, (G3) MTA + CaCl2 in contact with a moistened cotton pellet and (G4) MTA + CaCl2 immersed in PBS. The samples were stored for 3, 28 and 60 days. The bond strengths were measured with the Instron Testing machine. Data were analysed using the three‐way anova and Tukey test (P < 0.05).ResultsIn general, the samples of MTA with and without CaCl2, exposed to PBS, had higher bond strength values in all study periods (P < 0.05). Analysis of the influence of addition of CaCl2 to MTA (G1 × G3) evidenced significant differences in bond strength in the different periods (P < 0.05).ConclusionsThe exposure of MTA to PBS positively influenced the push‐out bond strength, whereas the addition of CaCl2 had a negative influence.
Push‐out bond strength of MTA with antiwashout gel or resins
Authors: Formosa L. M. , Mallia B. , Camilleri J. 
Published: July 2013

AbstractAimAssessment of the push‐out bond strength of four MTA‐based formulations for use as root‐end filling materials.MethodologyMTA Plus mixed with (i) water (‘MTA‐W’); (ii) a proprietary water‐based antiwashout gel (‘MTA‐AW’); (iii) Superbond C&B chemically curing resin (‘MTA‐Chem’); and (iv) Heliobond light‐curing resin (‘MTA‐Light’) was tested. Root slices 3 mm thick human had a 1.5 mm diameter hole drilled centrally and were treated with 17% EDTA for 60s. Forty specimens divided into groups 1–4 were prepared and filled with MTA‐W, MTA‐AW, MTA‐Chem and MTA‐Light, respectively. Groups 3 and 4 were etched with 37% phosphoric acid for 60s, and bonding agent was applied to the dentine surface. Specimens were stored for 28 days in Hanks’ Balanced Salt Solution at 37 °C. Push‐out strength was tested with a punch and die (punch diameter 1.3 mm, die diameter 2.0 mm, punch speed 1 mm min−1). Stereomicroscopy was used to classify failure mode (adhesive, cohesive or mixed type).ResultsThe resulting push‐out strengths were 5.1 MPa (MTA‐W), 4.3 MPa (MTA‐AW), 4.7 MPa (MTA‐Chem) and 11.0 MPa (MTA‐Light). MTA‐W had higher push‐out strength than MTA‐AW (P = 0.022). The same was noted for MTA‐Light relative to the other materials (P < 0.05). All materials exhibited adequate push‐out strengths compared with MTA‐W. Failure was predominantly mixed, except for MTA‐Chem (predominantly adhesive).ConclusionsAll materials exhibited adequate push‐out strength. Previous studies have shown the new formulations have additional advantages including increased washout resistance and faster setting time, making them promising for future dental applications.
Investigation of the interaction between (−)‐epigallocatechin‐3‐gallate with trypsin and α‐chymotrypsin
Authors: Wu Xuli , He Weiyi , Wang Wenpu , Luo Xinpin , Cao Heyao , Lin Lixia , Feng Kaiqian , Liu Zhigang 
Published: July 2013

SummaryTea polyphenol (TP) inhibits digestive enzymes and reduces food digestibility. To explore the interaction between TP with digestive enzymes, bindings of ‐epigallocatechin‐3‐gallate (EGCG) to trypsin and α‐chymotrypsin were studied in detail using fluorescence, resonance light‐scattering, circular dichroism, fourier transform infrared spectroscopy methods and protein‐ligand docking. The binding parameters were calculated according to Stern–Volmer equation, and the thermodynamic parameters were determined by the van't Hoff equation. The results indicated that EGCG was capable of binding trypsin and α‐chymotrypsin with high affinity, resulting in a change of native conformation of these enzymes. EGCG had a greater influence on the structure of α‐chymotrypsin than trypsin. This study can be used to explain the binding interaction mechanism between TP and digestive enzymes.
Studies on saffron (Crocus sativus L.) from Tuscan Maremma (Italy): effects of geographical origin, cultivation environment and drying method on volatile emission
Authors: Macchia Mario , Ceccarini Lucia , Molfetta Ilaria , Cioni Pier Luigi , Flamini Guido 
Published: July 2013

SummarySaffron (Crocus sativus L.) is a spice used in the food industry in an ever increasing, partly due to consumer preference for natural products. Crocus sativus stigmas are converted into saffron spice by a dehydration treatment. The postharvest treatment of the stigmas, particularly the drying process, is critical to the quality of saffron as measured by the level of secondary metabolites. The aim of this project was to study the volatiles compounds in saffron that came from three different sites of the Maremma Grossetana (Grancia, Pari and Alberese) (Tuscan). The corms were grown both in the place of origin and in the province of Pisa. Fifteen compounds were detected, accounting from 92.3% to 97.8% of the total volatiles. The main characteristic volatile compounds of the dried stigmas saffron were safranal, isophorone, 4‐keto isophorone, γ‐pyronene, dihydrooxophorone. Differences were found in the composition of volatile compounds both based on the place of cultivation and in a function of time of dehydration.
Measuring shear stress at lowest possible shear rates and improving viscosity determination of fat suspensions, for example chocolates
Authors: Bolenz Siegfried , Tischer Theresa 
Published: July 2013

SummaryIn industrial practice, flow property results are frequently discussed due to deviations caused by the measurement method. This project intended to improve preciseness of measuring fat suspensions like chocolate masses at very low shear using a rotary viscosimeter. Results showed no impreciseness at continuous shear rates of 0.03 s−1 and above. A new measurement profile including constant shear of 0.05 s−1 and flow curve evaluation according to Windhab and Casson models was created. Measuring seventeen different chocolates and comparing with a previous method showed changes in numerical results. Shear stress at constant 0.05 s−1 approximated to Casson and Windhab yield values; they were brought into agreement. Linear correlation between the various data sets at low and high shear rates gave acceptable results, thus allowing any of the models to be used in laboratory practice. Finally, repeatability at low shear was further improved after fine tuning and avoiding wall slip effects.
Development of a micromechanical damage model for assessing lifetime due to cyclical mechanical loading
Authors: Krätschmer D. , Roos E. 
Published: July 2013

ABSTRACTThe safe assessment of temporary service load changes necessitates a fatigue analysis in general. Recent computation methods try to include the microcrack growth corresponding to fatigue in the assessment of the material damage. A new damage model, which is based on the development and evolution of microcracks, has been developed. The stochastic character of the initiation and growth of microcracks enables a more realistic description of the material damage. Within this scope the development of the model is presented and its correlation with experimental results is shown. Fatigue tests under uniaxial and torsional loadings were carried out with specimens made of austenitic stainless steel X6CrNiNffe1666‐bib‐0018–10 S (1.4550). The calculated results of the microcrack length distribution show for both uniaxial and multiaxial loading a good agreement with experimentally achieved data. Using the expectation value of the calculated surface microcrack distribution as the governing variable to predict the number of cycles to crack initiation NA, a good correlation between lifetime and local microcrack length distributions for complex loading conditions can be drawn.
Desempleo parcial, la respuesta alemana a la Gran Recesión
Authors: BRENKE Karl , RINNE Ulf , ZIMMERMANN Klaus F. 
Published: July 2013

Resumen.A mediados de 2009, en el punto álgido de la crisis, había en Alemania 1,5 millones de trabajadores en régimen de desempleo parcial, lo cual impidió probablemente un aumento del desempleo mucho mayor del que se registró. Los autores advierten sin embargo de que su efecto amortiguador debe mucho a las circustancias particulares del país, por lo que no pueden generalizarse estos resultados. Además, las reformas legislativas subsiguientes favorecen el abuso del mecanismo, como refleja el número significativo de trabajadores en régimen de desempleo parcial en industrias no afectadas por la crisis y la emergencia de un patrón de aplicación del régimen por periodos prolongados.
Evaluación macroeconómica de las políticas activas del mercado de trabajo en España: ¿mucho ruido y pocas nueces?
Authors: ARRANZ José María , GARCÍA SERRANO Carlos , HERNANZ Virginia 
Published: July 2013

Resumen.Este artículo presenta una evaluación macroeconómica de algunas políticas activas del mercado de trabajo en España (en particular, los subsidios a la contratación indefinida) utilizando un panel agregado de datos de las comunidades autónomas (regiones) para el periodo 1987–2010. Los resultados sugieren que los subsidios a la contratación indefinida no han producido efectos apreciables sobre los niveles agregados de empleo o de temporalidad, aunque parecen haber influido de forma positiva pero pequeña en las transiciones del desempleo a la ocupación y del empleo temporal al indefinido, siendo el impacto mayor en el subperiodo 1997–2010, es decir, a partir de la reforma de 1997.
Dielectric, Ferroelectric, and Piezoelectric Properties of BiFeO3–BaTiO3 Ceramics
Authors: Wei Yongxing , Wang Xiaotao , Zhu Jintao , Wang Xiaoli , Jia Jiangjiang 
Published: July 2013

Perovskite solid solution ceramics of (1 − x)BiFeO3–xBaTiO3 (1 − x)BF–xBT, 0.2 ≤ x ≤ 0.45) with high electrical resistivity were prepared by solid‐state reaction method. Actual ferroelectric hysteresis loops and temperature dependence of dielectric constant of the ceramics were obtained. Ceramics of 0.7BF–0.3BT with small rhombohedral distortion show highest remnant polarization (Pr = 26.0 μC/cm2) and piezoelectric coefficient (d33 = 134 pC/N). Compositions with pseudo‐cubic symmetry (intermediate phases) show relaxor‐like dielectric anomaly. The values of Pr and d33 decrease with increasing BT content, from 24.8 μC/cm2 and 104 pC/N for 0.65BF–0.35BT to 8.2 μC/cm2 and 5 pC/N for 0.55BF–0.45BT.