Hosing of a long relativistic particle bunch in plasma

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing

Uticaj bakterijskog inokulanta mlečne kiseline sa dodatkom enzima i gnječenog ječma na kemijski sastav i degradaciju proteina u silaži lucerke

In the experiment, forage (dry matter 216.3 g.kg-1) from the 1st cut of alfalfa (Medicago, sativa L.) cv, Radius, mown at the early flowering stage, was ensiled. Alfalfa was ensiled without inoculants; with lactic acid bacteria and enzyme inoculants; with rolled barley; or with rolled barley and lactic acid bacteria and enzyme inoculants. Rolled barley was added in amounts of 50,100, 150 and 200 g.kg-1 of alfalfa forage, The bacterial acid enzyme inoculants (Bactozym) contained cultures of Lacto bacillus casein, Enterococcus faecium M74 and Pediococcus sp. (a total of 1 5 x 109 CPU in Ig of friable preparation) in the powdered part and the cellulase-hemicellulase complex (25000 n cat. in 1ml) and glucose-oxidase (4000 n cat. in 1ml) in the liquid part. The inoculants was used in a water solution in the amount of 10mg bacterial component and 0,2 ml enzymatic component / kg-1 alfalfa forage. The supplement of only rolled barley to alfalfa forage was found to have no significant effect on improving the processes of proteolysis and deamination in this type of silages, compared to alfalfa silages made with bacterial and enzyme inoculants. Significantly lower crude protein and WSC losses in the fermentation process, increased intensity of lactic acid fermentation, the lack of propionic and butyric acid fermentation, and significantly reduced processes of protein degradation were found in alfalfa-rolled barley silages made with the addition of lactic acid bacteria and enzyme inoculants.U ovom ogledu, silirana je stočna hrana (suva materija 216.3 g.kg-1) koja potiče od 1. otkosa lucerke (Medicago, sativa L.) cv, Radius, košene u ranom stadijumu cvetanja. Lucerka je silirana bez inokulanata; sa bakterijama mlečne kiseline i enzimskim inokulantom; sa gnječenim ječmom; ili sa gnječenim ječmom i bakterijom mlečne kiseline i enzimskim inokulantom. Gnječeni ječam je dodavan u količinama od 50, 100, 150 200 g.kg-1 stočne hrane od lucerke. Bakterijski enzimski inokulant (Bactozym) koji je sadržavao sledeće kulture Lacto bacillus casei ,Enterococcus faecium M74 i Pediococcus sp. ( ukupno 15 x IO9 CFU u Ig preparat koji se lako pretvara u prah) u prahu i kompleks celulaza-hemicelulaza (25000 n cat. u l ml) i glukoza-oksidaza (4000 n cat u Iml) u tečnom delu. Inokulant je korišćen u vodenom rastvoru u količini od 10mg bakterijske komponente i 0.2ml enzimske komponente / kg-1 lucerke. Dodavanje samo gnječenog ječma lucerkinom krmivu nije imalo značajnog efekta na poboljšanje procesa proteoloze i deaminacije u ovoj vrsti silaže, u poređenju sa silažama od lucerke koje su pravljene uz pomoć bakterijskih i enzimskih inokulanata. Signifikantno manje sirovog proteina kao i gubici WSC-a u procesu fermentacije, povećan intenzitet fermentacije mlečne kiseline, nedostatak fermentacije propionske i buterne kiseline, i znatno redukovani proces degradacije proteina su pronađeni u silaži od lucerke i gnječenog ječma uz dodatak bakterije mlečne kiseline i enzimskog inokulanta

Controlled Growth of the Self-Modulation of a Relativistic Proton Bunch in Plasma

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self -modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case

Temporal and between-site variation in helminth communities of bank voles (Myodes glareolus) from N.E. Poland. 1. Regional fauna and component community levels

Helminth infections were studied in bank voles (Myodes glareolus) from 3 woodland sites in N.E. Poland in the late summers of 1999 and 2002, to assess the temporal stability of derived statistics describing the regional helminth fauna and component community structure, and spatial influence on the latter. Regional helminth fauna changed dramatically between the two years, primarily due to a fall in the abundance of Syphacia petrusewiczi but was partially compensated for by an increase in Mesocestoides lineatus and Cladotaenia globifera. It was dominated by nematodes overall, but more so in 1999 than in 2002 when larval cestodes were more frequent. Most derived parameters for component community structure varied considerably between sites and the two surveys, the hierarchical order for sites not being maintained between surveys. They were susceptible to the disproportionate influence of three relatively rare, unpredictable species with the greatest overall aggregated distribution among hosts. Jaccard’s similarity index was less influenced by the rare species, showing greater stability between sites and across years. In conclusion, temporal variation confounded any site-specific characteristics of the summary measures quantified in this study and their usefulness is therefore restricted to the years in which the surveys were conducted

Controlled growth of the self-modulation of a relativistic proton bunch in plasma

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.info:eu-repo/semantics/publishedVersio

Drive counts as a method of estimating ungulate density in forests: mission impossible?

Although drive counts are frequently used to estimate the size of deer populations in forests, little is known about how counting methods or the density and social organization of the deer species concerned influence the accuracy of the estimates obtained, and hence their suitability for informing management decisions. As these issues cannot readily be examined for real populations, we conducted a series of ‘virtual experiments’ in a computer simulation model to evaluate the effects of block size, proportion of forest counted, deer density, social aggregation and spatial auto-correlation on the accuracy of drive counts. Simulated populations of red and roe deer were generated on the basis of drive count data obtained from Polish commercial forests. For both deer species, count accuracy increased with increasing density, and decreased as the degree of aggregation, either demographic or spatial, within the population increased. However, the effect of density on accuracy was substantially greater than the effect of aggregation. Although improvements in accuracy could be made by reducing the size of counting blocks for low-density, aggregated populations, these were limited. Increasing the proportion of the forest counted led to greater improvements in accuracy, but the gains were limited compared with the increase in effort required. If it is necessary to estimate the deer population with a high degree of accuracy (e.g. within 10% of the true value), drive counts are likely to be inadequate whatever the deer density. However, if a lower level of accuracy (within 20% or more) is acceptable, our study suggests that at higher deer densities (more than ca. five to seven deer/100 ha) drive counts can provide reliable information on population size

The effects of sex, age, season and habitat on diet of the red fox Vulpes vulpes in northeastern Poland

The diet of the red fox Vulpes vulpes was investigated in five regions of northeastern Poland by stomach content analysis of 224 foxes collected from hunters. The red fox is expected to show the opportunistic feeding habits. Our study showed that foxes preyed mainly on wild prey, with strong domination of Microtus rodents, regardless of sex, age, month and habitat. Voles Microtus spp. were found in 73% of stomachs and constituted 47% of food volume consumed. Other food items were ungulate carrion (27% of volume), other mammals (11%), birds (9%), and plant material (4%). Sex- and age-specific differences in dietary diversity were found. Adult males and juvenile foxes had larger food niche breadths than adult females and their diets highly overlapped. Proportion of Microtus voles increased from autumn to late winter. Significant habitat differences between studied regions were found. There was a tendency among foxes to decrease consumption of voles with increasing percentage of forest cover. Based on our findings, red foxes in northeastern Poland can be recognized as a generalist predators, consuming easily accessible and abundant prey. However, high percentage of voles consumed regardless of age, sex, month, or habitats may indicate red fox specialization in preying on Microtus rodents

Cyclic voles and shrews and non-cyclic mice in a marginal grassland within European temperate forest

Cyclic population dynamics of small mammals are not restricted to the boreal and arctic zones of Eurasia and North America, but long-term data series from lower latitudes are still less common. We demonstrated here the presence of periodic oscillations in small mammal populations in eastern Poland using 22-year (1986–2007) trapping data from marginal meadow and river valley grasslands located in the extensive temperate woodland of Białowieża Primeval Forest. The two most common species inhabiting meadows and river valleys, root vole Microtus oeconomus and common shrew Sorex araneus, exhibited synchronous periodic changes, characterised by a 3-year time lag as indicated by an autocorrelation function. Moreover, the cycles of these two species were synchronous within both habitats. Population dynamics of the striped field mouse Apodemus agrarius was not cyclic. However, this species regularly reached maximum density 1 year before the synchronized peak of root voles and common shrews, which may suggest the existence of interspecific competition. Dynamics of all three species was dominated by direct density-dependent process, whereas delayed density dependent feedback was significant only in the root vole and common shrew. Climatic factors acting in winter and spring (affecting mainly survival and initial reproduction rates) were more important than those acting in summer and autumn and affected significantly only the common shrew. High temperatures in winter and spring had positive effects on autumn-to-autumn changes in abundance of this species, whereas deep snow in combination with high rainfall in spring negatively affected population increase rates in common shrew

Development of the self-modulation instability of a relativistic proton bunch in plasma

Self-modulation is a beam–plasma instability that is useful to drive large-amplitude wakefields with bunches much longer than the plasma skin depth. We present experimental results showing that, when increasing the ratio between the initial transverse size of the bunch and the plasma skin depth, the instability occurs later along the bunch, or not at all, over a fixed plasma length because the amplitude of the initial wakefields decreases. We show cases for which self-modulation does not develop, and we introduce a simple model discussing the conditions for which it would not occur after any plasma length. Changing bunch size and plasma electron density also changes the growth rate of the instability. We discuss the impact of these results on the design of a particle accelerator based on the self-modulation instability seeded by a relativistic ionization front, such as the future upgrade of the Advanced WAKefield Experiment