Assessing Available Water Content of Sandy Soils to Support Drought Monitoring and Agricultural Water Management

Water Resources Management - In the future, according to regional climate-model simulations, the Carpathian Basin (in Central Europe) is predicted to be exposed to intensifying weather extremes...     

Inhomogeneity of CoCrW powder products manufactured by SLM technology

Journal of Mechanical Science and Technology - The article deals with selective laser melting process using CoCrW powder. Our aim was to identify the influence of product position on the building...     

Comparison of transsynaptic viral labeling of central nervous system structures from the uterine horn in virgin, pregnant, and lactating rats

Using the transneuronal viral tracing method, the central nervous system (CNS) connections of the uterine horn were studied in virgin, pregnant, and in lactating rats. The frequency of viral labeling in the brain and the distribution of virus-infected neurons from the uterine horn were compared among groups. There was a marked difference in the frequency of viral labeling in the brain stem. In virgin rats more than half of the brain stems (5 out of 9) were labeled. In contrast, in pregnant animals viral-labeled neurons were detected in only a few cases (3 out of 16) and almost each brain stem of the lactating group was labeled (12 out of 13). A similar, less marked difference was observed in the hypothalamus. The pattern of distribution of infected neurons was similar in each group. In the brain stem, the nucleus of the solitary tract, dorsal motor nucleus of the vagus, area postrema, gigantocellular and paragigantocellular nucleus, ventrolateral medulla, A5 cell group, and caudal raphe nuclei were the most frequently labeled structures. In the diencephalon, viral-infected neurons were detected primarily in the hypothalamic paraventricular nucleus. The telencephalon was devoid of infected cells. Data suggest that the CNS control of the uterine horn varies depending on reproductive status. The low frequency of brain labeling in pregnant rats may be related to the almost complete lack of sympathetic fibers in the uterus prior to parturition and the very high frequency of labeling in lactating animals to the postpartum hyperinnervation of the uterus.     

On the effects of the packet size distribution on the packet loss process

Real-time multimedia applications have to use forward error correction (FEC) anderror concealment techniques to cope with losses in today’s best-effort Internet. The efficiency of these solutions is known however to depend on the correlation between losses in the media stream. In this paper we investigate how the packet size distribution affects the packet loss process, that is, the distribution of the number of lost packets in a block, the related FEC performance and the average loss run length. We present mathematical models for the loss process of the MMPP+M/D/1/K and the MMPP+M/M/1/K queues; we validate the models via simulations, and compare the results to simulation results with an MPEG-4 coded video trace. We conclude that the deterministic packet size distribution (PSD) not only results in lower stationary loss probability than the exponential one, but also gives a less correlated loss process, both at a particular average link load and at a particular stationary loss probability as seen by the media stream.Our results show that for applications that can only measure the packet loss probability, the effects of the PSD on FEC performance are higher in access networks, where a single multimedia stream might affect the multiplexing behavior. Our results show that the effects of the PSD on FEC performance are higher in access networks, where a single multimedia stream might affect the multiplexing behavior and thus can improve the queuing performance by decreasing the variance of its PSD.     

Concentration of Pa231 from uranium process wastes

Sorption of protactinium from HNO₃ solutions with the aid of phosphate resins and various oxides is studied in connection with concentration of P_a ²³¹. Manganese oxide w as found to be the most efficient sorbent, with a high degree of freedom from iron, aluminum, and calcium impurities upon precipitation. The most pronounced differentiation between manganese and protactinium was achieved in solvent extraction by chlorex. The behaviorofprotactinium in response to various techniques for separation of titanium and zirconium was studied, and it was shown that in the salicylate method protactinium undergoes complete coprecipitation with zirconium salicylate. These operations led to the recovery by concentration of P_a ²³¹, the principal bulk component being zirconium.Translated from Atomnaya Énergiya, Vol. 16, No. 2, pp. 134–137, February, 1964     

Dispersal and attenuation of trace contaminants downstream of the Ajka bauxite residue (red mud) depository failure, Hungary

This paper identifies the spatial extent of bauxite processing residue (red mud)-derived contaminants and modes of transport within the Marcal and Ra?ba river systems after the dike failure at Ajka, western Hungary. The geochemical signature of the red mud is apparent throughout the 3076 km2 Marcal system principally with elevated Al, V, As, and Mo. Elevated concentrations of Cr, Ga, and Ni are also observed within 2 km of the source areas in aqueous and particulate phases where hyperalkalinity (pH < 13.1) is apparent. Although the concentrations of some trace elements exceed aquatic life standards in waters (e.g., V, As) and fluvial sediments (As, Cr, Ni, V), the spatial extent of these is limited to the Torna Creek and part of the upper Marcal. Source samples show a bimodal particle size distribution (peaks at 0.7 and 1.3 μm) which lends the material to ready fluvial transport. Where elevated concentrations are found in fluvial sediments, sequential extraction suggests the bulk of the As, Cr, Ni, and V are associated with residual (aqua-regia/HF digest) phases and unlikely to be mobile in the environment. However, at some depositional hotspots, association of As, Cr, and V with weak acid-extractable phases is observed.