1,728 research outputs found
Use of remotely-derived bathymetry for modelling biomass in marine environments
The paper presents results on the influence of geometric attributes of satellite-derived raster bathymetric data, namely the General Bathymetric Charts of the Oceans, on spatial statistical modelling of marine biomass. In the initial experiment, both the resolution and projection of the raster dataset are taken into account. It was found that, independently of the equal-area projection chosen for the analysis, the calculated areas are very similar, and the differences between them are insignificant. Likewise, any variation in the raster resolution did not change the computed area. Although the differences were shown to be insignificant, for the subsequent analysis we selected the cylindrical equal area projection, as it implies rectangular spatial extent, along with the automatically derived resolution. Then, in the second experiment, we focused on demersal fish biomass data acquired from trawl samples taken from the western parts of ICES Sub-area VII, near the sea floor. The aforementioned investigation into processing bathymetric data allowed us to build various statistical models that account for a relationship between biomass, sea floor topography and geographic location. We fitted a set of generalised additive models and generalised additive mixed models to combinations of trawl data of the roundnose grenadier (Coryphaenoides rupestris) and bathymetry. Using standard statistical techniques—such as analysis of variance, Akaike information criterion, root mean squared error, mean absolute error and cross-validation—we compared the performance of the models and found that depth and latitude may serve as statistically significant explanatory variables for biomass of roundnose grenadier in the study area. However, the results should be interpreted with caution as sampling locations may have an impact on the biomass–depth relationship
The effect of new anthracycline derivatives on the induction of apoptotic processes in human neoplastic cells.
This study was an attempt to determine the effect of a selected anthracycline derivative, WP903, on apoptotic processes in human melanoma cells depending on intracellular concentrations of the compound, and to evaluate the significance of apoptosis induction for the cytotoxic effect of anthracycline antibiotics. It was found that the WP903, contrary to ADR (adriamycin) is a strong inducer of apoptotic processes in ME18 human melanoma cells regardless of their susceptibility to adriamycin and WP903. The cells were treated for 24 h with ADR (1 and 5 microg/ml) or WP903 (0.2 and 2 microg/ml). Apoptosis was detected with the use of annexin V-FITC and PI (propidium iodide) and with TUNEL assay. WP903 used at 0.2 microg/ml induced early apoptosis in 23% of ME18 cells and in 60% of ME18/R cells; at 2 microg/ml in 70% of each of cell line tested. Significant late apoptotic effect was observed in ME18 cells. In contrast, ADR was found to be a weak inducer of apoptotic events. The results suggest that apoptosis is not a mechanism directly related to the cytotoxic effect of anthracycline antibiotics
An Answer to the Question about the Energetic Performance of TKX-50
Some of the relevant detonation performance parameters of TKX-50 were re-determined. The enthalpy of formation was obtained from the measured heat of combustion to be Delta H-f degrees (TKX-50(s))= + 213.4 +/- 1.2 kJ nnol (-1) The heat of detonation was measured to be 4650 +/- 50 kJ kg(-1). The detonation velocity of a TKX-50/wax mixture (97:3) at a density of 1.74 gcm(-3) was found experimentally to be 9190 m s(-1). Using the experimentally obtained enthalpy of formation for TKX-50 of +213.4 kJ mol(-1) and the experimentally determined solid-state density at room temperature of 1.887 gcm(-3) (TMD), the computed performance parameters for TKX-50 at its theoretical maximum density at room temperature was calculated to be as follows: VoD = 9642 ms(-1), p(C-J) = 37.0 GPa and Q(det) = 4770 kJ kg(-1)
Improved resource efficiency and cascading utilisation of renewable materials
In light of various environmental problems and challenges concerning resource allocation, the utilisation of renewable resources is increasingly important for the efficient use of raw materials. Therefore, cascading utilisation (i.e., the multiple material utilisations of renewable resources prior to their conversion into energy) and approaches that aim to further increase resource efficiency (e.g., the utilisation of by-products) can be considered guiding principles. This paper therefore introduces the Special Volume “Improved Resource Efficiency and Cascading Utilisation of Renewable Materials”. Because both research aspects, resource efficiency and cascading utilisation, belong to several disciplines, the Special Volume adopts an interdisciplinary perspective and presents 16 articles, which can be divided into four subjects: Innovative Materials based on Renewable Resources and their Impact on Sustainability and Resource Efficiency, Quantitative Models for the Integrated Optimisation of Production and Distribution in Networks for Renewable Resources, Information Technology-based Collaboration in Value Generating Networks for Renewable Resources, and Consumer Behaviour towards Eco-friendly Products. The interdisciplinary perspective allows a comprehensive overview of current research on resource efficiency, which is supplemented with 15 book reviews showing the extent to which textbooks of selected disciplines already refer to resource efficiency. This introductory article highlights the relevance of the four subjects, presents summaries of all papers, and discusses future research directions. The overall contribution of the Special Volume is that it bridges the resource efficiency research of selected disciplines and that it presents several approaches for more environmentally sound production and consumption
Radial Velocity Studies of Close Binary Stars.IV
Radial-velocity measurements and sine-curve fits to the orbital velocity
variations are presented for the fourth set of ten close binary systems: 44
Boo, FI Boo, V2150 Cyg, V899 Her, EX Leo, VZ Lib, SW Lyn, V2377 Oph, Anon Psc
(GSC 8-324), HT Vir. All systems are double-lined spectroscopic binaries with
only two of them not being contact systems (SW Lyn and GSC 8-324) and with five
(FI Boo, V2150 Cyg, V899 Her, EX Leo, V2377 Oph) being the recent photometric
discoveries of the Hipparcos satellite project. Five of the binaries are
triple-lined systems (44 Boo, V899 Her, VZ Lib, SW Lyn, HT Vir). Three (or
possibly four) companions in the triple-lined systems show radial-velocity
changes during the span of our observations suggesting that these are in fact
quadruple systems. Several of the studied systems are prime candidates for
combined light and radial-velocity synthesis solutions.Comment: aastex5.0, 5 figures in PS; submitted to Astron.
Stable and unstable accretion in the classical T Tauri stars IM Lup and RU Lup as observed by MOST
Results of the time variability monitoring of the two classical T Tauri
stars, RU Lup and IM Lup, are presented. Three photometric data sets were
utilised: (1) simultaneous (same field) MOST satellite observations over four
weeks in each of the years 2012 and 2013, (2) multicolour observations at the
SAAO in April - May of 2013, (3) archival V-filter ASAS data for nine seasons,
2001 - 2009. They were augmented by an analysis of high-resolution,
public-domain VLT-UT2 UVES spectra from the years 2000 to 2012. From the MOST
observations, we infer that irregular light variations of RU Lup are caused by
stochastic variability of hot spots induced by unstable accretion. In contrast,
the MOST light curves of IM Lup are fairly regular and modulated with a period
of about 7.19 - 7.58 d, which is in accord with ASAS observations showing a
well defined 7.247+/-0.026 d periodicity. We propose that this is the
rotational period of IM Lup and is due to the changing visibility of two
antipodal hot spots created near the stellar magnetic poles during the stable
process of accretion. Re-analysis of RU Lup high-resolution spectra with the
Broadening Function approach reveals signs of a large polar cold spot, which is
fairly stable over 13 years. As the star rotates, the spot-induced depression
of intensity in the Broadening Function profiles changes cyclically with period
3.71058 d, which was previously found by the spectral cross-correlation method.Comment: 14 pages, 7 figures. Accepted by MNRA
Unveiling ethical product features: The importance of an elaborated information presentation
© 2017 Elsevier Ltd Despite growing consumer awareness of ethical consumption, market sales are not growing accordingly. Because the presentation of appropriate ethical product information may influence consumers to choose ethical products, this paper analyses the requirements necessary for the successful communication of ethical product features. Based on McGuire's (1976) information-processing model, and a review of current literature, the information's comprehensibility, meaningfulness, and credibility are investigated in an online survey of US American citizens (n = 595) for two product categories representing Fast Moving Consumer Goods, and durable goods. A generalized mixed logit model revealed that all three communication factors affect consumers' choices. The more concerns about, or expertise in, organic production and fair trade purchase the consumers expressed, the less important their price sensibility and the more they preferred a comprehensive addendum and credible sources (e.g., government certificate or traceability). The results strongly suggest that advertisers and marketers can customize product communications in order to better engage both the mass market, and ethically oriented consumers
- …