Search

A 25-year-old intensive monoculture of cucumber (Cucumis sativus ‘Monolit F1’) has been chosen for monitoring the effect of continuous fertilization, drip irrigation and various soil disinfection on free-living nematodes in soil. Densities, relative abundance of nematode genera, trophic groups and c-p classes, in addition, numerous nematological indices were determined besides certain soil properties. Concerning the nematological indices, all the values proved a stressed, depleted and unstable environment with degraded food web condition. The exaggerated application of fertilizers through irrigation caused high salinity values (0.62 %) which is much higher than the indicated toxicity threshold (0.4 %) for cultivated plants. The number of individuals of the bacterivore Acrobeloides and Cuticularia genera, which have a very high stress tolerance, was outstanding in the area. Besides juveniles, the appearance of Meloidogyne incognita males was also recorded which could lead to a change in the genetic composition of the population to adapt to environmental stressors. All these changes may result from salt stress indicated by intensive drip irrigation and the use of artificial fertilizers.

While the nematicidal effectiveness of mulching against root-knot nematodes (Meloidogyne spp.) is calculated within organic crop protection, underlying mechanisms are not yet fully explored. Laboratory experiments were set up to determine whether mulch-derived substances cause mortality directly, or repel Meloidogyne juveniles from crop rhizosphere. Mortality and area choice tests were conducted with mulch-derived extracts, supported by the measurements on tannic acid content and the pH values of extracts as supplementary examinations. In our study, leaf litter and straw extracts were generally found lethal to the juveniles, which is in line with the results from area preference tests. However, compost extract had no effect on Meloidogyne incognita juveniles. Tannic acid content showed positive correlation with mortality only in the case of straw and sycamore leaf litter extracts. Tannic acid and pH weakly correlated with repellent effect of the applied extracts generally. Our results have inspired further experiments to explore nematicidal components of leaf litters, contributing to the development of a new approach in crop protection based on the repellent effect of these materials.

Summary: Background: Osteoarthritis (OA) of the distal intertarsal (DIT) and tarsometatarsal (TMT) joints occurs commonly. Synovial fluid (SF) biomarkers of collagen and bone turnover have potential clinical value. Objectives: To measure SF biomarker concentrations from DIT and TMT joints in adult horses and determine if they correlate with radiographic OA severity and are higher in joints with radiographic OA compared to controls. Study design: Cross‐sectional. Methods: Radiographic OA of DIT and TMT joints was evaluated from adult horses (5–35 years old). Overall radiographic scores divided horses into those with mild or moderate radiographic OA (16 joints from 9 horses) or controls (13 joints from 9 horses). Direct biomarkers of OA (Carboxypropeptide of type II collagen = CPII, carboxy‐neoepitope of type II collagen exposed after collagenase‐cleavage = C2C, Bone alkaline phosphatase = BAP and Chondroitin sulfate epitope = CS846) were measured via ELISA and CPII/C2C was calculated. Biomarkers were correlated with radiographic findings and concentrations from those with radiographic OA to control joints and were compared. Results: Concentrations of CPII (R = 0.84, P<0.001), C2C (R = 0.69, P<0.001) and BAP (R = 0.41, P = 0.03) as well as CPII/C2C (R = 0.69, P<0.001) values positively correlated with overall radiographic scores. Adjusted means ± s.d., after controlling for age, for CPII (P<0.001), C2C (P<0.001), CPII/C2C (P = 0.004) and BAP (P = 0.05) were significantly higher in DIT and TMT joints with radiographic OA (CPII: 2174.45 ± 1064.01; C2C: 233.52 ± 51.187; CPII/C2C: 9.01 ± 4.09; BAP: 21.98 ± 15.34) compared to controls (CPII: 594.53 ± 463.05; C2C: 153.12 ± 48.95; CPII/C2C: 3.96 ± 2.38; BAP: 12.76 ± 3.61). CPII (P<0.001), C2C (P = 0.001) and CPII/C2C (P = 0.001) were significantly higher with moderate radiographic OA (CPII: 2444.61 ± 772.78; C2C: 248.90 ± 44.94; CPII/C2C: 9.47 ± 2.97) compared to controls (CPII: 658.38 ± 417.36; C2C: 156.49 ± 47.61; CPII/C2C: 4.15 ± 2.04), with CPII also showing significantly higher concentrations (P = 0.04) with mild radiographic OA compared (1515.00 ± 584.95) to controls (658.38 ± 417.36). There were no differences in CS846 concentrations between radiographic OA and control joints. Age positively correlated with CPII (R = 0.48, P = 0.01) and C2C (R = 0.44, P = 0.02) concentrations. Main limitations: Radiographic OA was assessed, not clinical lameness. Controls were not age‐matched to those with spontaneous radiographic OA. Conclusions: There is an association between collagen (CPII, C2C and CPII/C2C) and bone (BAP) biomarkers and radiographic OA in the distal tarsal joints of horses. [ABSTRACT FROM AUTHOR]

The effectiveness of dimethyl disulfide (DMDS) to control root-knot nematodes (Meloidogyne spp.) and weeds was tested for the first time in Hungary in two consecutive protected cucumber crops with application made only before the first crop. The treatments were Accolade EC (DMDS 94.1%) at 400 l/ha applied by driplines, Nemathorin 10 G (fosthiazate) at 30 kg/ha, and an untreated control. During the first cucumber cycle vigour-index, yield, root-gall index, Meloidogyne juveniles in the soil and germination of weeds were evaluated. All considered parameters were significantly improved by using DMDS compared respectively to the chemical standard and untreated control: (i) vigour-index of 7.0, 4.3 and 3.6; (ii) cumulative yield/sample of 45.1 kg, 30.9 kg, and 16.6 kg; root-gall index (RGI) of 1.2, 4.9, and 5.9; (iii) M. incognita J2/25 g soil of 0.25, 48.5 and 78.0, and (iv) number of weed seedlings/sample in the 20–30 cm soil profile of 1.1, 2.6, and 4.2. During the second cucumber crop, only root-gall index was evaluated. Results showed that a single DMDS treatment applied before the first crop had a prolonged beneficial effect on the following crop. In the second crop cycle, root gall indices were 5.58, 9.18, and 8.44 for DMDS treated plots, chemical control and untreated control, respectively. [ABSTRACT FROM AUTHOR]

Few researches address the compatibility of organic mulching and entomopathogenic (EPN) and slug-parasitic (SPN) nematodes, although organic mulching may provide favourable conditions for these beneficial organisms. Our aim was to examine the effect of different concentrations (0.1, 0.5, 1 and 5%) of aqueous extracts of green waste compost, the dry leaf litters of the common walnut (Juglans regia) and Norway maple (Acer platanoides) on EPN (Heterorhabditis bacteriophora, Steinernema carpocapsae, Steinernema feltiae, Steinernema kraussei) and SPN (Phasmarhabditis hermaphrodita) species. Experiments were set up in 96-well, flat-bottom microplates. After a 24-hour exposure time, the number of dead animals was counted under a transmission microscope. Green waste compost extracts caused quite low or no mortality in case of all examined species. Mortality caused by the 5% Norway maple leaf litter extract was moderate (34.6%) in the case of S. carpocapsae juveniles, while 100% of juveniles of other species died. The highest (5%) concentration of the common walnut leaf litter extract caused 100% mortality in all species. As a conclusion, green waste compost mulch seems to be more compatible with EPN and SPN species than common walnut or Norway maple leaf litter mulch. [ABSTRACT FROM AUTHOR]

The submitted scientific experiment deals with the application of PVD (Physical Vapour Deposition) coating TiAlN+DLC in two different lubrication environments, also the article deals with the comparison of a lifetime of coating in mentioned lubricants. The PVD coating TiAlN+DLC was selected according to previous experiments carried out in the same field of laboratory works at Slovak University of Agriculture in Nitra. The coating was deposited on HCR (High Contact Ratio) gears with properties explained in chapter Materials and methods. HCR gears were selected according to the previous research performed on that type of gears. HCR gears were made from material 14 220 (16MnCr5). As lubrication environments were chosen ecological lubricant OMW Biogear S150 and conventional lubricant MADIT PP 90H. These two lubricants were selected according to the application in the previous research carried out in the workplace.Experimental tests were performed on the Niemann M01 FZG testing rig (back-to-back). That testing rig was used for the comprehensive measurement of the scuffing tests. In the experiment, we followed standard STN 65 6280, for FZG scuffing tests, from which we gained the load values for different load levels. After each load level were measured values of the maximum height of the measured profile Rz, by portable surface roughness tester Mitutoyo SJ-201, for the tip and the reference diameters on gear and pinion. Results of experimental tests were statistically processed and on a basis on them were established relations between the maximum height of the assessed profile and load level for both used lubricants as the dependence of change maximum height of the assessed profile Rz on the load level. Performed experiments showed that application of PVD coating TiAlN+DLC is possible in both used environments. [ABSTRACT FROM AUTHOR]

The storage and application of huge amounts of deep litter manure could be a serious issue generated by livestock systems. As broiler litter has high N and fiber content, pre-treatment is strongly recommended. Composting is one of the key method of pre-treatment. Due to Georgakakis and Krintas, 2000, Hosoya composting system is suitable for composting by-products with unfavourable properties such as poultry litter. The end-product (composted and pelletized poultry litter (CPPL)) is appropriate alternative to the substitute for chemical fertilizers, due to its pathogen-free, safe-to-use features and high organic content while it meets the requirements of the European Green Deal's goals. In the frame of research maize (ZEA MAYS L.) plant test was carried out to get information about the effects of CPPL and ammonium nitrate (AN) fertilizer in pot experiment conditions. Measurements cover the following analyses: the length of the roots, stems, and seedlings, the dry matter content, germination percent, Vigour-index, and chlorophyll and carotenoid content. On the whole, it can be stated that CPPL had higher stimulating impacts on measured parameters (root length, dry matter content, Vigour index) in comparison to AN with higher N content.

Effects of fermented chicken manure on soil nutrient availability, leaf nutrient status and fruit quality parameters were studied in an apple plantation from Eastern Hungary. Beside control, three fermented chicken manure products (BIO-FER Natur Extra, Nitro vit and 7-9-7) were used in a field experiment trial at the Horticultural Experimental Farm of University of Debrecen in 2020. In this trial, soil and leaf analysis were made to check the effects of applied treatments on the nutrient supply of the soil and the nutrient status of the leaves. Beside soil and leaf analysis, yield and some fruit quality parameters were investigated. The products were applied at the beginning of April in 2020. Each treatment consisted of 5 trees. Soil pH has slightly decreased during the trial. The organic carbon content of the soil has not significantly changed during the experiment. Chicken manure treatments could not affect considerably the soil P, K, Mg, Mn, Cu and Zn content compared to the control. All applied treatments increased the N content of leaves compared to the control, but the effect was not significant. Leaf P content was the same in all treatments, while the leaf K content was slightly higher where chicken products were used. Leaf Ca and Mg were not affected significantly by the treatments compared to the control. The usage of chicken manure increased yield, fruit weight and fruit flesh hardness compared to the control, but significant effect was observed only in certain treatments. Moreover, all applied treatments decreased the Brix value of apples compared to the control.

The paper presented determines that the rotation velocities of gears and radii connecting the axes of rotation of the gears with the point of their teeth gearing are not equal with each other. It is explained by the relative slip of involute gear profiles during their rolling. This phenomenon will become a prerequisite for further development of creation of mathematical models in the context of theory of gear hydraulic machines. The models can explain a number of specific phenomena in the operation of gear hydraulic machines, such as pressure and input pulsations, dynamics of hydraulic oil in the cut-off plane, combined torque pulsations in gear hydraulic motors and others.

The objective of this study was to investigate the viability of microalgae biomass (Chlorella vulgaris) as a substrate for anaerobic digestion using synthetic wastewater as well as evaluate the biogas production improvement and the microalgae cultivation rate. The experimental procedure lasted for 700 hours, where a mixture of synthetic wastewater and microalgae were used in the BE4 anaerobic tank reactor. Based on the process parameters (pH and temperature), the degradation phases (hydrolysis, acidogenesis (fermentation acidification), acetogenesis, methanogenesis) were successfully separated from each other. A drop in pH was detected from 7 to 4.5 in the acidogenesis phase, which resulted in a delayed decrease in the total chlorophyll concentration and the microalgae activity rate. In the methanogenesis phase, the pH slightly returned to neutral and caused a relatively low biogas yield (0.15 L in total), which can be explained by the unbalanced carbon/nitrogen rate (C : N) in relation to the substrate. The increase in total chlorophyll concentration was observed by the end of the process as a result of the increasing pH. It was found, that the concentration of major chemical constituents and the COD can be described well by logarithmical curves according to the nutrient consumption of microalgae. The COD decreased from the initial value of 5077 mg·L-1 O2 to 1592 mg·L-1 O2, which refers to anintensive anaerobic degradation process.

Piezoelectric micro-electro-mechanical system (MEMS) loudspeakers are drawing more interest due to their applications in new-developing audio technologies. MEMS devices’ small dimensions necessitate including thermal and viscous effects in the surrounding air when simulating their behaviors. Thus, the linearized mass, momentum and energy conservation equations are used to describe these effects. These formulations are implemented in our open-source finite element program openCFS. In this article, we model a 3D piezoelectric MEMS loudspeaker in two configurations: open and closed back-volume, which behave differently due to the effects of air viscosity and pressure forces between the cantilever and the closed back-volume. Furthermore, using a customized vacuum chamber, the atmospheric pressure is varied and its effects are studied in these two configurations, numerically and experimentally. Experimental results prove that our model predicts the behavior of the piezoelectric MEMS loudspeaker in various configurations very well. Additional simulations illustrate the effect of the slit thickness and thermal losses.

Maternal and progeny diets supplemented with 2 sources of trace mineral (TM) were evaluated for effects on the size and severity of osteochondrosis (OC) lesions in progeny produced by 64 Landrace × Large White sows. At breeding, sows were randomly assigned to maternal diets (gestation and lactation) consisting 1 of 2 TM treatments. One treatment consisted of inorganic TM (ITM) with ZnO, MnSO4, and CuSO4 at concentrations to provide 150, 50, and 16.5 mg/kg diet of Zn, Mn, and Cu, respectively. The other treatment consisted of the same ITM concentrations plus an additional 50, 20, and 10 mg/kg diet of Zn, Mn, and Cu, respectively, supplied by a blend of AA-complexed TM (CTM) using Availa Sow. Within maternal dietary treatment groups, selected progeny (n = 280) were fed either ITM- or CTM-supplemented diets. The humerus and femur (1 each) from progeny euthanized at 12 (n = 80) or 24 wk (n = 200) were collected for microscopic (12 wk) or gross (24 wk) assessment of OC lesions. Microscopic OC lesions were present in all pigs at 12 wk. Dietary treatments had limited effects on OC prevalence or severity. A maternal × progeny diet interaction (P = 0.044) revealed femoral OC latens lesions that were approximately twice the size in progeny fed CTM that were produced by sows fed CTM compared with those found in pigs in the other 3 dietary treatment groups. At 24 wk, the sum of gross OC scores at predilection sites of the thoracic (elbow joint) and pelvic (stifle and hock joints) limbs remained similar among treatments, despite greater (P = 0.004) gross OC scores of the medial femoral condyle in progeny from sows fed CTM diets than in progeny from sows fed ITM diets, regardless of progeny diet. Progeny produced by sows fed CTM vs. ITM had increased ADG (0.71 vs. 0.68 ± 0.01 kg/d), regardless of the diet fed to progeny during the growth phases. Covariant analysis using ADG did not alter inferences about maternal or progeny diet effects on OC responses. Although 100% of progeny at 12 wk had histologically apparent OC lesions, only 3 of the 200 pigs examined at 24 wk had gross lesions of sufficient severity to potentially result in clinically apparent disease. Therefore, although some results imply that maternal and progeny CTM diets increased the size (12 wk) and severity (24 wk) of OC in 1 site (the femur), on the whole animal level, no evidence of lameness was noted. [ABSTRACT FROM AUTHOR]

Presented paper deals with the issue of lubricating tribological systems formed by a double pair operating under mixed conditions of mixed friction before and after experimental tests, which were conducted in accordance with the selected methodology using Tribotestor M‘06 test machine. The lubricating media included ecological oils Plantohyd 46 S by Fuchs and EAL Hydraulic 46 manufactured by the Mobil company. Applied ecological oils can be used in agricultural mobile machines as a replacement for conventional lubricants. The tests were conducted on designated material double pairs. The shaft was made of steel 16MnCr5. The second observed friction element in terms of glide angle test was a steel plate made of S235JR, gliding surface of which was produced utilizing flame powder coating technology. The results were statistically processed and are presented in the form of graphs, tables and figures.

Meat chicken (broiler) industry continuously increasing all over the world. Due to it, the amount of waste from the chicken industry is also increasing. Therefore, more efficient conversion of chicken manure to organic fertilizer is key problem all over the world. Therefore, the aims of present study are to investigate the changes in temperature and moisture content during composting of chicken manure in a tank fermentation system and create a model to describe the biodegradation processes. In this study, Hydrus software was used for modelling the moisture and temperature distribution in the oval tank during the decomposing processes. It was found that the studied oval tank fermenter can be divided into two main parts considering to the changing of temperature and moisture level. In the first phase - after the intake – where the rate of biodegradation is high there is a heterogeneous temperature zone with decreasing moisture content. Moreover, in this stage a special temperature profile was found at the cross-sectional view of the tank. The second phase was more homogenous both in temperature and moisture content. This stage is the weak fermentation part of the technology results an elongated post fermentation section. It was established, that the changes of temperature and moisture content along the tank fermenter are the same and there is a strong connection between them in the examined period. Our results pointed out that the initial turning and mixing results in a large temperature and moisture content drop and later there is sufficient time for composting to take place. The authors recommend that this system could be used as an efficient treatment for chicken manure materials to decompose and get a valuable base organic fertilizer.

Proposed paper deals with experimental tests performed on the Nieman M01 FZG test rig. Experiments were carried out in accordance with STN 65 6280 standard for FZG scuffing tests, from which load values for each load level were obtained. HCR gears made of 16MnCr5 material were utilized during experimental tests. Gear surface was deposited by PVD coatings of nACRo4 and TiAlN + DLC. Conventional lubricant MADIT PP 90H and biological lubricant OMW Biogear S150 were selected for lubrication environments. Aim of the experimental tests lied in application and comparison of PVD coatings deposited on HCR gears. Values of the maximum height of the assessed profile Rz for tip and reference diameters were measured after each load level. Results of experimental tests were statistically processed and relations between the maximum height of assessed profile Rz and load levels for both utilized coatings in both environments were established on the basis of these results.

Copyright of Stratum Plus Journal is the property of P.P. Stratum plus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Pituitary pars intermedia dysfunction (PPID) is a risk factor for pasture-associated laminitis, which follows a seasonal pattern. Hypothesis: Hormonal responses to season differ between PPID and unaffected horses. Animals: Seventeen horses aged 8–30 years (14 horses ≥ 20 years of age). Methods: Longitudinal observational study. Blood was collected monthly from August 2007 until July 2008 after pasture grazing and again after overnight stall confinement. Blood hormone and metabolite concentrations were measured and pasture grass samples were analyzed to determine carbohydrate content. Analysis of variance analysis for repeated measures was performed. Results: Mean ACTH concentrations varied significantly over time ( P < .001), with higher concentrations detected in August, September, and October compared with November–April. Pasture × time effects were detected for glucose and insulin concentrations, with peaks observed in September. Horses were retrospectively allocated to PPID (n = 8) and control (n = 9) groups on the basis of plasma ACTH concentrations. Changes in insulin concentrations over time differed in the PPID group when compared with the control group. Insulin concentrations were positively correlated with grass carbohydrate composition. Conclusions and Clinical Importance: PPID did not affect the timing or duration of the seasonal increase in ACTH concentrations, but higher values were detected in affected horses. Insulin concentrations differed between groups, but hyperinsulinemia was rarely detected. Glucose and insulin concentrations peaked in September when horses were grazing on pasture, which could be relevant to the seasonal pattern of laminitis. [ABSTRACT FROM AUTHOR]