METHODOLOGICAL APPROACHES TO ACCELERATED TESTS OF CRUSHING KNIVES OF GRINDING CATS. COMPARATIVE TESTS OF LOSS OF CUTTING CAPACITY

The purpose of the research is to analyze the design features and parameters of grinding knives to compare the intensity of loss of cutting ability of each of the models of knives depending on the load cycles. Methods and materials. Conduct an analytical inspection and instrumental studies of the blades of grinding rollers type KR with different design features. Carry out bench accelerated tests based on the cyclic impact load of the knife fragment due to falling on the simulator of wear cycles and check the residual cutting capacity on the cutting simulator. Justify the coefficient of acceleration of tests as a derivative of hardness and density of the simulator, as well as the ratio of the energy of the fall of the knife fragment on the stand and its rotational motion in the field. Statistical analysis of experimental data was performed by analysis of variance and interpreted by standard computer programs Excel in the form of graphs. Results. Analyzing the proposed method for determining the intensity of loss of cutting ability of the knife when it falls on the simulator of plant debris allowed to rank different models and establish their relative resource. Unhardened models of both 45 and 30MnB5 Steel provide low life and their residual cutting ability is only 15-25% compared to hardened models. Analyzing the research results, the hardened model of a knife made of 45 Steel withstands 4 times more load cycles compared to unhardened models, but is inferior to the hardened model of Steel 30MnB5 (borista), which has the highest resource. Even after 150 load cycles (in terms of the work of a roller with a width of 12.5 m - operating time of more than 1000 ha), it retains more than 55% of the initial cutting ability, which is characterized by low intensity of its loss. Conclusions. According to the tests of the intensity of loss of cutting ability of knives, the most acceptable option for the equipment of roller-shredders is a hardened model made of 30MnB5 Steel (borista), which has the highest resource.

KOMPOSISI DAN LUAS RELUNG MAKANAN IKAN PALUNG (Hampala macrolepidota C.V.1823) DI WADUK PB. SOEDIRMAN BANJARNEGARA, JAWA TENGAH

This study aims to determine the composition and value of the natural feed niche of trough fish caught from the waters of the PB Reservoir. Sudirman. The research method used is a survey method with a sampling technique using purposive random sampling. The research location was divided into three stations, namely I (Karang Kemiri), II (Wanadadi), and III (Karang Jambe). Sampling was carried out three times (19 February, 07 March, and 2 August 2020). Data were analyzed descriptively comparatively. The results showed that the composition of the trough fish diet was dominated by Chlorophyta and plant debris. Based on the selectivity index and the most significant part of trough fish, including omnivorous fish. Large trough fish have a high food niche area. Small, medium and large trough fish have stiff competition for food in the waters

Cellulose in atmospheric particulate matter

The spatiotemporal variations of free cellulose concentrations in atmospheric particles, as a proxy for plant debris, were investigated using a novel HPLC-PAD method. Filter samples were taken from nine sites of varying characteristics across France and Switzerland, with sampling covering all seasons. Concentrations of cellulose, as well as carbonaceous aerosol and other source-specific chemical tracers (e.g. Elemental Carbon (EC), levoglucosan, polyols, trace metals, and glucose) were quantified. Annual mean free cellulose concentrations within PM10 ranged from 29 ± 38 ng m−3 at Bern (urban site) to 284 ± 225 ng m−3 at Payerne (rural site). Concentrations were considerably higher during episodes, with spikes exceeding 1150 and 2200 ng m−3 at Payerne and ANDRA-OPE (rural site), respectively. A clear seasonality, with highest cellulose concentrations during summer and autumn, was observed at all rural and some urban sites. However, some urban locations exhibited a weakened seasonality. Contributions of cellulose-carbon to total organic carbon are moderate on average (0.7–5.9 %), but much greater during ‘episodes’, reaching close to 20 % at Payerne. Cellulose concentrations correlated poorly between sites, even a ranges of about 10 km, indicating the localised nature of the sources of atmospheric plant debris. With regards to these sources, correlations between cellulose and typical biogenic chemical tracers (polyols and glucose) were moderate to strong (Rs 0.28−0.78, p < 0.0001) across the nine sites. Seasonality was strongest at sites with stronger biogenic correlations, suggesting the main source of cellulose arises from biogenic origins. A second input to ambient plant debris concentrations was suggested via resuspension of plant matter at several urban sites, due to moderate cellulose correlations with mineral dust tracers, Ca2+ and Ti metal (Rs 0.28−0.45, p < 0.007). No correlation was obtained with the biomass burning tracer (levoglucosan), an indication that this is not a source of atmospheric cellulose. Finally, an investigation into the interannual variability of atmospheric cellulose across the Grenoble metropole area was completed. It was shown that concentrations and sources of ambient cellulose can vary considerably between years. All together, these results deeply improve our knowledge on the phenomenology of plant debris within ambient air.

Effect of Repeated Plant Debris Reutilization as Organic Amendment on Greenhouse Soil Fertility

Greenhouse agriculture typically generates large amounts of waste with plant residue (agricultural biomass) being the most abundant. This residue is generated on a seasonal basis, which complicates the external management of the material. Recently, the European Union (EU) has been implementing a policy based on sustainability through the circular economy that seeks to minimize waste generation. The effect of reusing 3.5 kg·m−2 tomato plants from the previous season as the only fertilizer versus no fertilization and inorganic fertilization in 215-day tomato cycles after transplanting was studied in this trial. The study was carried out during three seasons in greenhouse agriculture in Almeria (Spain) with the repeated use of the solarization technique. The plant debris had similar production results during two of the three seasons and fruit quality parameters were similar to inorganic fertilization. In addition, some physicochemical variables improved and the biological depressive effect of solarization was mitigated. The results suggest that the reuse of the tomato plant debris as the only fertilizer could be an alternative to conventional fertilization under the conditions tested.

Hitchhiking Halophytes in Wrack and Sediment-Laden Ice Blocks Contribute To Tidal Marsh Development in The Upper Bay of Fundy.

Salt marshes are a type of coastal wetland that are affected by dynamic coastal processes. Ice blocks and wrack (mats of plant debris) regularly float onto northern marshes and become stranded, affecting vegetation and soil accretion. There is little research regarding the capacity of ice and wrack to transport viable plant propagules onto marshes where they can colonize, which may be particularly important at barren new salt marsh restoration sites. Contributions of sediment by ice may also be important at restoration sites to raise the marsh platform to elevations appropriate for plant colonization. We collected ice (n = 27) and wrack (n = 18) samples at marshes in the Bay of Fundy, ran germination trials with the contents, and measured the quantity of sediment in the ice. We found viable propagules from halophytic and non-halophytic species in wrack, and viable propagules of Sporobolus pumilus in ice. Additionally, we found sediment densities between 0.01 and 4.75 g·cm−3 in ice blocks that translated to 26.61 – 21,483.59 kg of total sediment per block, representing a large source of sediment. We found that the number of germinating propagules could not be predicted by wrack size, and that pH, sediment density, sediment weight in ice blocks were variable across the marsh surface, while ice salinity was negatively correlated with elevation and distance from creek. Our results indicate that ice and wrack represent a potential source for vegetation colonization at salt marsh sites and highlights their contributions to facilitating vegetation colonization through building marsh soils.

Management of Green Waste Streams from Different Origins: Assessment of Different Composting Scenarios

The organic wastes of plant origin and, in particular, those coming from sources related to tourism activities, such as those generated from golf courses and touristic coasts, constitute an increasing concern due to the rise in their production and their unsuitable management. Thus, this work aimed to assess the use of different composting strategies to manage these specific green wastes, such as grass clippings and pruning waste from a golf course and marine plant debris, mainly from posidonia (Posidonia oceanica L.). To this end, two composting scenarios were established: the first only considered green wastes in the composition of the composting mixtures, and the second used sewage sludge as a co-composting agent. The temperature of the piles was monitored, and physicochemical and chemical parameters were also studied throughout the process. The results obtained showed that composting is a feasible method to manage and recycle this type of green waste, obtaining end products with suitable physicochemical and chemical characteristics. However, proportions of sea plant wastes in the composting mixture higher than 30% can compromise the fertilizing value of the final compost. Moreover, the use of an additional co-composting agent (sewage sludge) improved the characteristics of the end products obtained, provided that this co-composting agent had suitable initial characteristics.

Comparative biology of four Rhodanthidium species (Hymenoptera, Megachilidae) that nest in snail shells

Some species of two tribes (Anthidiini and Osmiini) of the bee family Megachilidae utilize empty gastropod shells as nesting cavities. While snail-nesting Osmiini have been more frequently studied and the nesting biology of several species is well-known, much less is known about the habits of snail-nesting Anthidiini. We collected nests of four species of the genus Rhodanthidium (R. septemdentatum, R. sticticum, R. siculum and R. infuscatum) in the Czech Republic, Slovakia, Catalonia (Spain) and Sicily (Italy). We dissected these nests in the laboratory and documented their structure, pollen sources and nest associates. The four species usually choose large snail shells. All four species close their nests with a plug made of resin, sand and fragments of snail shells. However, nests of the four species can be distinguished based on the presence (R. septemdentatum, R. sticticum) or absence (R. siculum, R. infuscatum) of mineral and plant debris in the vestibular space, and the presence (R. septemdentatum, R. infuscatum) or absence (R. sticticum, R. siculum) of a resin partition between the vestibular space and the brood cell. Rhodanthidium septemdentatum, R. sticticum and R. siculum usually build a single brood cell per nest, but all R. infuscatum nests studied contained two or more cells. For three of the species (R. siculum, R. septemdentatum and R. sticticum) we confirmed overwintering in the adult stage. Contrary to R. siculum, R. septemdentatum and R. sticticum do not hide their nest shells and usually use shells under the stones or hidden in crevices within stone walls. Nest associates were very infrequent. We only found two R. sticticum nests parasitized by the chrysidid wasp Chrysura refulgens and seven nests infested with pollen mites Chaetodactylus cf. anthidii. Our pollen analyses confirm that Rhodanthidium are polylectic but show a preference for Fabaceae by R. sticticum.

The spread of cat-transmitted sporotrichosis due to Sporothrix brasiliensis in Brazil towards the Northeast region

Background Sporotrichosis is a worldwide subcutaneous mycosis caused by Sporothrix spp. In the past, this infection was associated with armadillo hunting, horticulturists, miners, and gardeners, being considered an implantation mycosis acquired by plant debris injury. Nevertheless, since the late nineties, it has been considered a zoonotic disease in Brazil. Here we report a case series of 121 patients with cat-transmitted sporotrichosis seen in Northeast Brazil. Methodology/Principal findings Patient’s demographic, clinical data, and length of treatment were recorded. In addition, a mycological examination and further PCR confirmation of species identification were performed. One hundred and twenty two patients were diagnosed with subcutaneous sporotrichosis from October 2016 to December 2019, while PCR revealed that 71 of them were due to S. brasiliensis. The majority of the individuals were female (n = 86; 70.5%). Patient’s age ranged from 5 to 87 years old. The clinical forms found were lymphocutaneous (58.2%) and fixed cutaneous (39.4%). Interestingly, 115 patients reported previous contact with cats diagnosed with sporotrichosis. Patients were successfully treated with itraconazole and potassium iodide. Conclusions/Significance Our study adds important contributions for the investigation of the spread of cat-transmitted subcutaneous sporotrichosis in Brazil, specifically towards the Northeast region of a continental-size country. It will also help clinicians to be aware of the existence and importance to accurately diagnose sporotrichosis and treat patients with this infectious disease in the lowest income region of Brazil.

CONTRIBUTIONS TO THE KNOWLEDGE OF THE STRUCTURE AND ECOLOGICAL INDICES OF COLEOPTERS POPULATIONS IN THE WALNUT ORCHARDS

The observations were made during 2019 and 2020 in a walnut orchard from Sârca farm, in Iasi County. The material was collected using Barber-type soil traps during the two years of research, at a time interval between 10 and 14 days from May to August inclusive, thus integrating a number of 10 or 8 harvests in 2019 and 2020. The biological material collected was cleaned of plant debris and then prepared for identification, at the level of order, and for the specimens of beetles we made the determination up to the species level. From the analysis of the collected material it results that the collected specimens belong to the Hexapoda Class, the Coleoptera order. The species of coleopters insects collected belong to the species: Anysodactilus binotatus, Harpalus pubescens, Otiorrhynchus pinastri, Dermestes laniarius, Harpalus tenebrosus, Amara crenata, Paramalus paralelipipedus, Colodera aethiops, Phyllotreta attra, Harpalus calceatus

Survival of Xanthomonas cucurbitae in different cropping rotations, plant debris, and weeds in pumpkin fields

This study was conducted to evaluate the effectiveness of crop rotation in managing Xanthomonas cucurbitae, the causal agent of Xanthomonas leaf spot, in pumpkin fields. The study was conducted using ‘Howden’ pumpkin, a susceptible pumpkin cultivar, at four sites with no history of Xanthomonas leaf spot. All sites were planted with pumpkins in the first year of crop rotations. The disease developed at all four sites. In a three-year rotation with nonhost crops, the severity of Xanthomonas leaf spot in pumpkin plots was significantly (P<0.05) lower than those of plots in the two-year rotation with nonhost crops and continuous pumpkin production. Furthermore, X. cucurbitae was recovered from pumpkin plant debris 15 months after harvesting pumpkins in commercial fields, and the pathogen was viable. X. cucurbitae was also isolated from asymptomatic weeds in pumpkin fields. In a greenhouse inoculation of weeds with X. cucurbitae, however, Xanthomonas leaf spot developed only on leaves of bur cucumber (Sicyos angulatus) and velvetleaf (Abutilon theophrasti) weeds. In the infested soil with X. cucurbitae, the bacterium was not recovered after 15, 42, and 56 days at 22, 12, and 4℃, respectively. The results showed that crop rotation alone does not provide adequately protection of pumpkin plants against X. cucurbitae.