59 research outputs found

    Grass silage thickening technology using centrifugal undirected action vibrator

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    A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

    Vibration and noise measurements during silage thickening with inertia directional vibrator

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    Literature review and performed theoretical investigation indicates that it is environmentally and economically feasible for small and average size farms to use vibrational thickening method for silage preparation. However, the results need to be verified with experiments. This research work provides analysis and evaluation of flat surface inertia type vibrator, in which the excitation force is induced by turning the unbalanced mass. Directed action vibrator was manufactured and tested. Results indicate that application of inertia directional vibrator for thickening of finely chopped corn and Jerusalem artichoke stalk mixture, after 40 minutes thickening, allows to obtain a 114.6 kg m-3 density for both layers, while thickening the first 65 kg mass mixture layer after 10 minutes - a 197.9 kg m-3 density. Dry material densities correspond to 61.5 and 106.3 kg m-3 respectively. After examination of fodder quality it was determined that corn mixture silage, thickened by the inertia directional vibrator, satisfies highgrade silage requirements. Performed tests demonstrated that the effect of vibrations on whole body and the measured noise levels do not have detrimental effect on human health and the established acceptable limits are not exceeded while operating the inertia directional vibrator. The vibrator is suitable for silage preparation since it does not contaminate the fodder with dirt and gasoline products during operation. The proposed silage preparation method provides opportunities to use ecologically safe containers as well as sectional and other types of enclosure

    Grass silage thickening technology using centrifugal undirected action vibrator

    Get PDF
    A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

    Grass silage thickening technology using centrifugal undirected action vibrator

    Get PDF
    A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

    Vibration and noise measurements during silage thickening with inertia directional vibrator

    Get PDF
    Literature review and performed theoretical investigation indicates that it is environmentally and economically feasible for small and average size farms to use vibrational thickening method for silage preparation. However, the results need to be verified with experiments. This research work provides analysis and evaluation of flat surface inertia type vibrator, in which the excitation force is induced by turning the unbalanced mass. Directed action vibrator was manufactured and tested. Results indicate that application of inertia directional vibrator for thickening of finely chopped corn and Jerusalem artichoke stalk mixture, after 40 minutes thickening, allows to obtain a 114.6 kg m-3 density for both layers, while thickening the first 65 kg mass mixture layer after 10 minutes - a 197.9 kg m-3 density. Dry material densities correspond to 61.5 and 106.3 kg m-3 respectively. After examination of fodder quality it was determined that corn mixture silage, thickened by the inertia directional vibrator, satisfies highgrade silage requirements. Performed tests demonstrated that the effect of vibrations on whole body and the measured noise levels do not have detrimental effect on human health and the established acceptable limits are not exceeded while operating the inertia directional vibrator. The vibrator is suitable for silage preparation since it does not contaminate the fodder with dirt and gasoline products during operation. The proposed silage preparation method provides opportunities to use ecologically safe containers as well as sectional and other types of enclosure

    The Influence of B Cell Depletion Therapy on Naturally Acquired Immunity to Streptococcus pneumoniae

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    The anti-CD20 antibody Rituximab to deplete CD20+ B cells is an effective treatment for rheumatoid arthritis and B cell malignancies, but is associated with an increased incidence of respiratory infections. Using mouse models we have investigated the consequences of B cell depletion on natural and acquired humoral immunity to Streptococcus pneumoniae. B cell depletion of naïve C57Bl/6 mice reduced natural IgM recognition of S. pneumoniae, but did not increase susceptibility to S. pneumoniae pneumonia. ELISA and flow cytometry assays demonstrated significantly reduced IgG and IgM recognition of S. pneumoniae in sera from mice treated with B cell depletion prior to S. pneumoniae nasopharyngeal colonization compared to untreated mice. Colonization induced antibody responses to protein rather than capsular antigen, and when measured using a protein array B cell depletion prior to colonization reduced serum levels of IgG to several protein antigens. However, B cell depleted S. pneumoniae colonized mice were still partially protected against both lung infection and septicemia when challenged with S. pneumoniae after reconstitution of their B cells. These data indicate that although B cell depletion markedly impairs antibody recognition of S. pneumoniae in colonized mice, some protective immunity is maintained, perhaps mediated by cellular immunity

    Antibiotic Treatment of the Tick Vector Amblyomma americanum Reduced Reproductive Fitness

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    BACKGROUND: The lone star tick Amblyomma americanum is a common pest and vector of infectious diseases for humans and other mammals in the southern and eastern United States. A Coxiella sp. bacterial endosymbiont was highly prevalent in both laboratory-reared and field-collected A. americanum. The Coxiella sp. was demonstrated in all stages of tick and in greatest densities in nymphs and adult females, while a Rickettsia sp. was less prevalent and in lower densities when present. METHODOLOGY/PRINCIPAL FINDINGS: We manipulated the numbers of both bacterial species in laboratory-reared A. americanum by injecting engorged nymphs or engorged, mated females with single doses of an antibiotic (rifampin or tetracycline) or buffer alone. Burdens of the bacteria after molting or after oviposition were estimated by quantitative polymerase chain reaction with primers and probes specific for each bacterial species or, as an internal standard, the host tick. Post-molt adult ticks that had been treated with rifampin or tetracycline had lower numbers of the Coxiella sp. and Rickettsia sp. and generally weighed less than ticks that received buffer alone. Similarly, after oviposition, females treated previously with either antibiotic had lower burdens of both bacterial species in comparison to controls. Treatment of engorged females with either antibiotic was associated with prolonged time to oviposition, lower proportions of ticks that hatched, lower proportions of viable larvae among total larvae, and lower numbers of viable larvae per tick. These fitness estimators were associated with reduced numbers of the Coxiella sp. but not the Rickettsia sp. CONCLUSION/SIGNIFICANCE: The findings indicate that the Coxiella sp. is a primary endosymbiont, perhaps provisioning the obligately hematophagous parasites with essential nutrients. The results also suggest that antibiotics could be incorporated into an integrated pest management plan for control of these and other tick vectors of disease

    Multivalent vaccines demonstrate immunogenicity and protect against Coxiella burnetii aerosol challenge

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    Vaccines are among the most cost-effective public health measures for controlling infectious diseases. Coxiella burnetii is the etiological agent of Q fever, a disease with a wide clinical spectrum that ranges from mild symptoms, such as fever and fatigue, to more severe disease, such as pneumonia and endocarditis. The formalin-inactivated whole-cell vaccine Q-VAX® contains hundreds of antigens and confers lifelong protection in humans, but prior sensitization from infection or vaccination can result in deleterious reactogenic responses to vaccination. Consequently, there is great interest in developing non-reactogenic alternatives based on adjuvanted recombinant proteins. In this study, we aimed to develop a multivalent vaccine that conferred protection with reduced reactogenicity. We hypothesized that a multivalent vaccine consisting of multiple antigens would be more immunogenic and protective than a monovalent vaccine owing to the large number of potential protective antigens in the C. burnetii proteome. To address this, we identified immunogenic T and B cell antigens, and selected proteins were purified to evaluate with a combination adjuvant (IVAX-1), with or without C. burnetii lipopolysaccharide (LPS) in immunogenicity studies in vivo in mice and in a Hartley guinea pig intratracheal aerosol challenge model using C. burnetii strain NMI RSA 493. The data showed that multivalent vaccines are more immunogenic than monovalent vaccines and more closely emulate the protection achieved by Q-VAX. Although six antigens were the most immunogenic, we also discovered that multiplexing beyond four antigens introduces detectable reactogenicity, indicating that there is an upper limit to the number of antigens that can be safely included in a multivalent Q-fever vaccine. C. burnetii LPS also demonstrates efficacy as a vaccine antigen in conferring protection in an otherwise monovalent vaccine formulation, suggesting that its addition in multivalent vaccines, as demonstrated by a quadrivalent formulation, would improve protective responses

    Impact of Abandoned Land on Environmental Protection, Landscape and Economic Benefit in Lithuania

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    Abstract. Human economic activity is defined as an anthropogenic process that has a negative impact on natural envi-ronment. The urbanisation and agricultural development influence the environment mostly. In order to receive economic benefit to the above-mentioned activities, the landscape is changed, the soil is affected and pollutants are released into the environment. In the light of the fact that the identified processes and problems caused by them are global, the variety of international directives are designed to minimise the impact of anthropogenic activities on the environment. The territory of the Republic of Lithuania has a considerable amount of areas, where the economic activity is sus-pended, i.e. the land is abandoned. This is due to a variety of social, natural and economic reasons. This process can be perceived as opposite to the anthropogenic activity, however it is important to examine how it affects the environment, landscape or economic needs. These processes are relevant on the local and international level, therefore, the scientific results of this article may be useful for the professionals in various areas and further research. The research investigates the territory of abandoned agricultural land, which is to be urbanised in the future. Land cadastre data, spatial planning documents are analysed, a questionnaire-based survey is conducted, and the actual inspec-tion in the area is carried out. The research results identify the causes for non-use of the land, and the impact of no eco-nomic activity on the environment, the landscape and the economic performance. To reach the set objectives, the data analysis, synthesis, induction methods have been used

    Ectopic hbox12 Expression Evoked by Histone Deacetylase Inhibition Disrupts Axial Specification of the Sea Urchin Embryo

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    Dorsal/ventral patterning of the sea urchin embryo depends upon the establishment of a Nodal-expressing ventral organizer. Recently, we showed that spatial positioning of this organizer relies on the dorsal-specific transcription of the Hbox12 repressor. Building on these findings, we determined the influence of the epigenetic milieu on the expression of hbox12 and nodal genes. We find that Trichostatin-A, a potent and selective histone-deacetylases inhibitor, induces histone hyperacetylation in hbox12 chromatin, evoking broad ectopic expression of the gene. Transcription of nodal concomitantly drops, prejudicing dorsal/ventral polarity of the resulting larvae. Remarkably, impairing hbox12 function, either in a spatially-restricted sector or in the whole embryo, specifically rescues nodal transcription in Trichostatin-A-treated larvae. Beyond strengthen the notion that nodal expression is not allowed in the presence of functional Hbox12 in the same cells, these results highlight a critical role of histone deacetylases in regulating the spatial expression of hbox12
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