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Solar wind parameters at different locations in the inner heliosphere can be estimated using various solar wind extrapolation methods. The simple ballistic method extrapolates solar wind parameters from the point of measurement to a chosen heliospheric position by assuming that major solar wind structures are persistent and arrive relatively unaltered to the target position. The method considers the rotation period of the Sun while assuming a constant solar wind speed during radial propagation. We improve the simple ballistic model by considering the interaction between the slow and the fast solar wind with a pressure correction during the propagation. Instead of extrapolating from the position of a single spacecraft, we apply this pressure-corrected ballistic method to 2D speed maps of the solar source surface available from solar coronal models to determine the solar wind speed in the inner heliosphere in 3D, between latitudes of ±50°. We also take into account the effects of the solar differential rotation in our model. Our method is simple and fast, and it can be applied to different source surface datasets. The results of our model are validated with in situ data from the ACE spacecraft. We find that the pressure-corrected ballistic method can give accurate predictions of the solar wind in 3D.

Corotating Interaction Regions (CIRs) are complex structures in the Heliosphere that arise from the interaction of fast and slow solar wind streams. The interface between fast and slow solar wind is called the stream interface, which often has considerable north-south tilt. We apply a sliding window correlation method on multi-spacecraft data in order to obtain the time delay between the spacecraft. Using these time delays and in-situ solar wind velocity measurements, we can shift the positions of two spacecraft, and, together with the position of the reference spacecraft, we can reconstruct the spatial orientation of the stream interface. We examined four CIRs from two different solar sources at the beginning of 2007 using ACE, WIND, and STEREO-A spacecraft data. The gradually increasing distance between STEREO-A and the other spacecraft provides an opportunity to determine the effects of spacecraft separation on the quality of the results. In three out of the four events, the determined planes generally follow the Parker spiral in the ecliptic, their off-ecliptic tilt is determined by the position of the source of the high-speed stream. For the fourth event, STEREO-A was probably too far away for this method to be successfully applied.

This study aimed to investigate the interrelationships between key harmful emission components, nitrogen oxides (NO x ), and particulate numbers (PNs) in diesel engine exhaust and the control actuators of diesel engines. This research involved conducting a series of experiments under fixed parameters within an engine brake laboratory environment to elucidate these correlations. The objectives of this study were to conduct a comprehensive review of the relevant emissions technology literature and a comparative assessment of particle measurement methods based on dilution ratios and develop innovative aerosol preparation principles tailored to condensation particle measurement. Additionally, this research involved designing and implementing an aerosol preparation unit based on the newly developed principles, along with the creation of test cell control programs using the AVL PUMA Open TST editor interface and Visual Basic. Furthermore, this study was concerned with conducting evaluations of fixed-parameter engine dynamometer tests to explore the functional relationships between the emission of 10/23 nm particles, NO x emissions, common rail pressure variations, and exhaust gas recirculation levels. This study aimed to enhance the understanding of diesel engine emissions dynamics and contribute valuable insights for developing more efficient and environmentally friendly engine control strategies.

Passenger and commercial transportation significantly contribute to hazardous air pollution. Exhaust gas after-treatment technology advances closely to the emission regulations throughout the world. The upcoming legislation will be EURO VII in European Union, which requirements are not set yet, but the Solid Particle Number (SPN) diameter range is expected to be more severe compared to EURO VI. This paper will revisit the measurement principle differences between over 10 nm and over 23 nm diameter particles in theory and practical engine bench measurement. Two different types of particle counters have performed the soot particle counting measurement; therefore, the applied sensors are different in terms of applied counting principles. The measurement principles of both devices will be introduced, and the experiment's result will reflect on the sensor differences. From this, a conclusion can be derived in order to determine the severity of the upcoming EURO VII legislation in terms of SPN, and the experiment will also reflect on the measurement sensor differences. The overall results suggested that extending the lower range of the measurement increases the tailpipe particle emission by 20%, although the DPF filtration efficiency is still over 99%., Competing Interests: N.B. is employed by Ibiden Hungary Ltd., which supplies diesel particle filters (DPF). The rest of the authors declare no conflict of interest.

The European hedgehog (Erinaceus europaeus) is known to host several ectoparasites and also tick-borne pathogens, but there is scant information on its eastern relative, the Northern white-breasted hedgehog (Erinaceus roumanicus). We have studied an urban population of E. roumanicus in a city park of central Budapest, Hungary, for 2 years to investigate their tick and flea species. A total of 5063 ticks and 818 fleas were collected from 247 hedgehogs (including 46 recaptures). Ectoparasite prevalence and intensity differed significantly (p<0.001) between the 2 study years attributable to the enhanced tick removal rate due to anaesthesia used in the second year. The most common tick species was Ixodes ricinus (93.7%) followed by unidentified Ixodes larvae (5%). Only 57 hedgehog ticks (I. hexagonus) were removed from 22 hedgehogs. One I. acuminatus and one Hyalomma marginatum nymph were also collected. Mean intensity of tick infestation was 26.5 (range: 0-155 ticks/host) and mean intensity of flea infestation was 6.6 (range: 0-78 fleas/host). Most fleas (99.4%) collected were hedgehog fleas (Archaeopsylla erinacei), dog fleas (Ctenocephalides canis) were found on 2 hedgehogs. Hyalomma marginatum has previously not been found in Hungary, and I. acuminatus was only reported sporadically before. The large number of ectoparasites and the 2 imported tick species may thus survive in close proximity to humans if hedgehogs are present. This calls attention to the risk of possible tick-borne human infections that urban hedgehogs can pose., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

To evaluate the presence of rickettsial agents in hippoboscid flies with molecular methods, 81 sheep keds (Melophagus ovinus) were collected from 23 sheep, 144 deer keds (Lipoptena cervi) were caught in the environment, and a further 463 and 59 individuals of the latter species were obtained from fresh carcasses of 29 red deer and 17 roe deer, respectively. DNA was extracted individually or in pools. Anaplasma ovis was demonstrated in all examined sheep keds, and from one pool of free-living deer keds. Rickettsia helvetica or other, unidentified rickettsiae were also present in one pool of sheep keds, and in four pools of deer keds from both red deer and roe deer. This is the first account of polymerase chain reaction positivity of hippoboscid flies for A. ovis and rickettsiae. These results raise the possibility that-apart from cattle and roe deer as already reported-sheep and red deer might also play a reservoir role in the epidemiology of rickettsioses.

A 5-year-old female degu (Octodon degus ) showed the clinical sign of metrorrhagia. During ovariohysterectomy a circumscribed tumoural lesion was found in the right uterine horn. The histopathological diagnosis of this soft tissue mass was primary benign cavernous angioleiomyoma of the uterus. During immunohistochemical analysis the neoplastic endothelial cells of this mixed mesenchymal tumour showed strong membrane positivity for the endothelial marker claudin-5 but were negative for CD31 (another endothelial marker). The endothelial cells of the internal positive control tissues such as intact peritumoural vessels were positive for claudin-5 but negative for the CD31 endothelial marker. As it has been described also in other species, it seems that claudin-5 is a better endothelial marker than CD31 for the detection of normal and neoplastic endothelial cells in different tissues of degus.

Myosin, HMM and HMM S1 catalyze 18O-exchange between P1 and H218O of the medium at an intermediate stage of ATP hydrolysis ("intermediate 18O-exchange") in the presence of Mg2+. Natural complexes of actomyosin and acto-HMM S1 do not catalyze intermediate 18O-exchange but facilitate "direct" or "medium" 18O-exchange (KH2P18O4 in equilibrium H2O) even without ATP. Reconstituted complexes of actomyosin, acto-HMM, acto-HMM S1, PABC-HMM S1, congo-myosin and TNP-myosin do not catalyze direct 18O-exchange in the presence of Mg2+ and absence of ATP. From the data obtained a hypothetical sequence of phosphorylation and 18O-exchange reactions in myofibril action has been suggested.