Fourteen symposia on early/lower vertebrates have taken place over the last 50 years, usually at about four year
intervals. An average 60 participants have taken part at these symposia, with over one hundred occasionally. The
results of the symposia have been published in proceedings. The symposia started honoring E. A:son Stensiö and
E. Jarvik. Honors were taken up at the 11th symposium in Uppsala again. Since the 13th symposium a Stensiö
award is also given to young researchers in the field.
The present article attempts to discuss whether a medical conference poster intended for a specific English-speaking discourse community shares the properties of discourse colony (Hoey 1986). The author analyses 12 e-posters, which were displayed during an international neurological conference, presenting findings on epilepsy treatment. First, the author characterises the conference poster, which is followed by a description of discourse community and discourse colony. Next, the analysis of the e-posters is carried out and the results of the analysis are presented. On the basis of these results it might be said that the medical conference poster could be considered a discourse colony as it shares some of its properties.
Acoustic signal is more and more frequently used to diagnose machines operated in industrial conditions where installation of sensors is hindered. Impact of background noise seems to be the major problem as part of analysis of such signal. In most cases of industrial environments, background level is high; thus, it prevents against concluding as per standard methods that have been used in diagnostic testing. This study specifies the problem related to diagnosing machines operated under variable loads. Synchronous methods are used for diagnosing these types of machines, those include synchronisation of diagnostic signal with revolutions of the diagnosed machine. For the purpose of this study an acoustic signal was used as the diagnostic signal. Application of the synchronous method (order analysis) enables eliminating an impact of background noise derived from other sources. This study specifies application of acoustic signal to diagnose planetary gear in laboratory testing rig in order to discover damages at early stage of degradation. This method was compared with the method basing on measurement of vibrations.
Coexisting microorganisms are abundant in nature. Plant growth promoting rhizobacteria (PGPR) is a group of beneficial microorganism living around the roots of plants which are able to confer beneficial effects on plant growth. Streptomyces sp. is a gram-positive bacteria as PGPR that can promote plant growth and enhance tolerance in adverse environment. This research was aimed to study the effects of plant growth promotion and stress tolerance of Streptomyces sp. in Arabidopsis and Brassica sp. The amount of indole-acetic acid (IAA) and phosphate solubility were assessed from isolated bacterial. Plant growth promotion was examined in 10-days old seedling with three independent experiments. Our results showed that Streptomyces sp. produced moderate levels of IAA and it was able to solubilize phosphate. Inoculation of Streptomyces sp. enhanced lateral root number, fresh weight and chlorophyll content in Arabidopsis thaliana. Moreover, the inoculation of Streptomyces sp. significantly increased vegetative growth on Arabidopsis and Brassica sp. by producing higher fresh weight and chlorophyll content. Streptomyces sp. also enhanced tolerance to abiotic stress in Arabidopsis and Brassica sp. by increasing fresh weight under condition of salt and heat stress. Under salt stress, inoculation of Streptomyces sp. in Arabidopsis induced activity of catalase enzyme and decreased hydrogen peroxide (H2O2) and malondialdehyde (MDA) production. In the molecular levels, Streptomyces sp. induced protein accumulations in Arabidopsis including nitrogen assimilation (GS1), carbohydrate metabolism (cFBPase), and the light-harvesting chlorophyll (Lhcb1) protein.
In this paper both envelope approach and morphological filters for characterisation of surface textures were proposed, applied and thoroughly examined. Obtained results were compared with those received after appliance of commonly-used algorithms. The effect of appliance of proposed procedures on surface topography parameters (from ISO 25178 standard) was taken into consideration. The following types of surface textureswere assessed: two-process plateau-honed cylinder liners, plateau-honed cylinder liners with additionally burnished dimples, turned piston skirts, grinded and/or isotropic topographies. It was assumed that envelope characteristics (envelope filtration) can provide results useful for assessments of deep and/or wide oil-reservoirs especially when they are edge located. Moreover, some near-valley areas of surface texture details can be less distorted when envelope filtering is accomplished. It was also found that closing and/or opening envelope filtration can be valuable for reduction of some surface topography measurement errors.
The present study was undertaken to highlight the influence of simvastatin administration on hepatocyte morphology, proliferation, and apoptosis. The study included 48 gilts aged 3 months (weighing ca. 30 kg) divided into groups I (control; n=24) and II, receiving 40 mg/animal simvas- tatin orally (simavastatin; n=24) for 29 days. The animals were euthanized on days subsequent to the experiment. The livers were sampled, fixed, and processed routinely for histopathology, histochemistry, and immunohistochemistry (for proliferating cell nuclear antigen, Bcl-2, and caspase-3). Apoptosis was visualized by terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL). Simvastatin administration caused acute hepatocyte swelling, glycogen de- pletion, hyperaemia, multifocal hepatocyte proliferation with occasional pseudoacinar formation, connective tissue hyperplasia, eosinophil infiltration, and interface hepatitis. The proliferating cell nuclear antigen index, mean diameter of argyrophilic nucleolar organizer regions, and Bcl-2 immunoexpression were lower compared to control, and mean caspase-3 immunoexpression was higher in group II compared to control. On day 25 and 29 single hepatocytes in the simvasta- tin-treated group were TUNEL-positive. Simvastatin caused morphological alteration which became more intense over time. The results from the present study suggest that simvastatin treat- ment may cause glycogen, lipid metabolism and cell membrane permeability distortion, fibrosis, interface hepatitis, reduction in hepatocyte proliferation and transcriptional activity, and enhanced vulnerability to apoptosis. Summing up the results, it can be concluded that simvastatin caused liver damage with similar morphological changes seen in autoimmune-like liver injury, which may indicate that simvastatin may induce autoimmune-like drug induced liver injury.
This article proposes an analytical model of a system with priorities servicing a mixture of different elastic traffic streams. The model presented in the article was developed as the extension of earlier works published by the authors. It utilizes the concept of equivalent bandwidth and then, following bandwidth discretization, uses the dependencies introduced on the basis of the assumptions adopted for the generalized Kaufman-Roberts formula and for the model of a full-availability group with traffic compression. The article presents a possibility of using the proposed model to model the radio interface in a multi-service mobile network and provides an example of the above with the interface of an LTE network. Since the proposed model is an approximate one, the results of the calculations are compared with the results of simulations. A comparison of the results confirms an acceptable level of accuracy of the model. The model can be successfully used in the analysis and design of links and nodes of telecommunication and computer networks.
Construction and demolition (C&D) waste management should be accordance with the waste management hierarchy. In practice, C&D waste are often downcycling. It is the result of many factors, including lack of awareness about the value inherent in waste. The paper presents analysis of the adaptability of non-destructive testing (NDT) methods for technical assessment of waste properties. As part of the work, non-destructive testing methods were described and classified in accordance with material and the features they enable testing. The publication presents examples of the use of NDT in the recovery of building materials during construction projects, in the field of influence of technical information of waste on the way it is managed. Finally, a scheme of waste management process during the renovation of an object with the application of NDT methods was presented.
The mechanical properties of cement paste modified by nano-TiO2 (nT) and nano-SiO2 (nS) were experimentally studied. The compressive strength increased first and then decreased with the increase of nanoparticle content. When nanoparticles were added into the cement paste as a filler to improve the microstructure, the two kinds of particles both could form a tighter mesh structure, which would enhance the density and strength of the structure. The elastic modulus increased rapidly with the increase of the nT content and reached a peak when the nanoparticle content is about 3%, which was about twice the elastic modulus of ordinary cement paste. The Scanning electron microscopy (SEM) observation results showed that the microstructure of cement was network connection and fiber tube. The hydration progress of ordinary cement slurry was insufficient, and many unreacted cement particles remained. With the addition of nanoparticles, the internal structure of the cement became denser, with fewer pore cracks, smaller pore diameters, more complex fiber tube arrangements, and significant anisotropy, thereby improving strength and mechanical properties.
High voltage direct current (HVDC) emergency control can significantly improve the transient stability of an AC/DC interconnected power grid, and is an important measure to reduce the amount of generator and load shedding when the system fails. For the AC/DC interconnected power grid, according to the location of failure, disturbances can be classified into two categories: 1) interconnected system tie-line faults, which will cause the power unbalance at both ends of the AC system, as a result of the generator rotor acceleration at the sending-end grid and the generator rotor deceleration at the receiving-end grid; 2) AC system internal faults, due to the isolation effect of the DC system, only the rotor of the generator in the disturbed area changes, which has little impact on the other end of the grid. In view of the above two different locations of disturbance, auxiliary power and frequency combination control as well as a switch strategy, are proposed in this paper. A four-machine two-area transmission system and a multi-machine AC/DC parallel transmission system were built on the PSCAD platform. The simulation results verify the effectiveness of the proposed control strategy.
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The aim of any industrial plant, which is dealing in the energy sector, is to maximise the revenue generation at the lowest production cost. It can be carried out either by optimizing the manpower or by improving the performance index of the overall unit. This paper focuses on the optimisation of a biomass power plant which is powered by G50 hardwood chips (Austrian standard for biomass chips). The experiments are conducted at different operating conditions. The overall effect of the enhanced abilities of a reactor on the power generation is examined. The output enthalpy of a generated gas, the gas yield of a reactor and the driving mechanism of the pyrolysis are examined in this analysis. The thermal efficiency of the plant is found to vary from 44 to 47% at 400◦C, whereas it is 44 to 48% for running the same unit at 600 ◦C. The transient thermal condition is solved with the help of the lumped capacitance method. The thermal efficiency of the same design, within the constraint limit, is enhanced by 5.5%, whereas the enthalpy of the produced gas is magnified by 49.49% through nonlinear optimisation. The temperature of biomass should be homogenous, and the ramping rate must be very high. The 16% rise in temperature of the reactor is required to reduce the mass yield by 20.17%. The gas yield of the reactor is increased by up to 85%. The thermal assessment indicates that the bed is thermally thin, thus the exterior heat transfer rate is a deciding factor of the pyrolysis in the reactor.
Finger vein biometric systems become increasingly more popular because they offer higher security comparing to other authentication solutions with respect to positive persons experience. Those systems operate on near infrared light (NIR) in wavelength range from around 700 to 1000 nm, however dedicated research to determine impact of NIR lighting on biometric system effectiveness has not been conducted and presented in the literature ever before. In this paper the study of correlation between wavelengths in NIR spectra and effectiveness of person identification in a biometric system is presented. To achieve that goal, a new model of image acquisition system allowing change of light wavelengths has been created and NIR finger vein dataset containing 11 556 images was established. Furthermore, this model was used to perform experimental work and proof that some NIR wavelengths better suit for vein patterns acquisition, allowing to increase the recognition effectiveness of finger vein biometric systems.
Although the Antarctic has avoided the worst effects of alien species, its future seems endangered due to increasing natural and man-made pressures. Rapid changes in three major environmental variables have occurred in the Antarctic region during the last decades. In the short term terrestrial biota are likely to benefit from reduced environmental stresses, but in the long run the colonization of the region by lower latitude species with greater competitive ability will become increasingly important and can lead to large-scale changes in biological composition and trophic complexity in some existing Antarctic terrestrial ecosystems. Moreover, the recent dynamic climate changes combined with human activities in the Antarctic region might modify the status of several alien species which have hitherto been considered transient or persistent and could, therefore, become naturalized and threaten the native communities on a larger scale than today, or influence the status of naturalized species.