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Aim. To evaluate the changes in the total cellularity (Nuc) of the rat sciatic nerve regenerative neuroma (RegN) and its representation of CD90, CD44, CD146, and CD133 positive cells, as well as its neurotization under the conditions of dexamethasone (Dex) and granulocyte colony-stimulating factor (GCSF). Materials and methods. After injections of dexamethasone and granulocyte colony-stimulating factor in the regenerative neuroma of 168 male Wistar rats, CD90, CD44, CD146 and CD133 positive cells were detected immunohistochemically in the regenerative neuroma. Its total cellularity and neurotization were determined and statistical processing of the obtained data was performed. Results. It was found that dexamethasone and granulocyte colony-stimulating factor change the representation of cellular patterns and neurotization of regenerative neuroma. Conclusions. The amount of neurotization of the regeneration neuroma directly depends on the specific amount of Schwann cells in its composition. Dex and GCSF, despite different mechanisms of action, lead to an increase in the content of neuroleumocytes in RegN.

Aim. To evaluate the change of the content of mesenchymal (vimentin-positive) and reparative Schwann (GFAP-positive) cells in the regenerative neuroma of the rat sciatic nerve, taking into account the activity of local homeostasis regulation (CD73 expression) under the influence of dexamethasone (Dex) and granulocyte colony-stimulating factor (GCSF). Materials and methods. Vimentin-, GFAP-, and CD73-positive cells were detected immunohistochemically in the regenerative neuroma of 168 male Wistar rats, and their presence was quantified using statistical methods. Results. The regenerative neuroma of the sciatic nerve is characterized by a stereotypical cellular composition kinetics. Dexamethasone, during the initial stage of neuroma formation (1–7 days), led to a reduction in inflammatory infiltration and accumulation of vimentin+ mesenchymal cells. It significantly accelerated the accumulation of neural GFAP+ reparative Schwann cells and suppressed the expression of CD73. The granulocyte colony-stimulating factor (1–3 days) in the regenerative neuroma resulted in a slight reduction in inflammatory infiltration and an increase in the number of blood vessels penetrating into it. Under these conditions, the speed and quantity of vimentin+ cell accumulation and CD73 expression noticeably increased, as well as the speed of GFAP+ cell accumulation. The deviations in the expression of vimentin, GFAP, and CD73 in the neuroma under the administration of the mentioned substances gradually decreased and, after 8 weeks of the experiment, did not differ significantly from the control. When combined, dexamethasone and granulocyte colony-stimulating factor potentiated each other’s effects and, in addition, led to long-term maintenance of high CD73 expression. At the same time, the most pronounced approximation of the structure of the newly formed part of the nerve to the structure of the intact nerve trunk was observed. Conclusions. The simultaneous action of Dex and GCSF during the initial stages of regenerative neuroma formation, in contrast to their individual actions, not only alters the dynamics of mesenchymal and neural cell accumulation but also modifies the newly formed part of the nerve, bringing its structure closer to the intact state. This phenomenon is accompanied by increased reactivity of neurolemocytes during the axial cylinder germination stage of neuroma regeneration.

This study was performed to determine whether active optical sensors could develop an algorithm for N recommendation for the potato crop (Solanum tuberosum L.). The experiment was conducted in Maine State, (USA) during the growing season of 2018-2019. Six N rates (0-280 kg ha-1) were applied on eleven locations under a randomized complete block design (RCBD), with four replications. Data of normalized difference vegetation index-(NDVI) were collected via active sensors, GreenSeeker-(GS), and Crop Circle-(CC). Sensors measurements collected at the 20th of the leaf stage were significantly associated with tuber yield, where the exponential model exhibited a better fit for the regression curve. Conventionally, 168 kg N ha-1 produced the maximum potato yield. The N rate computed based on in-season sensors reading reduced by about 12-14% from the total N rate that growers use to apply based on the conventional approach. Studying potato cultivars separately in the same soil properties can improve the algorithm accurately.

More contemporary options have been presented in the last few years as surgical methods and materials have improved in patients with degenerative spine illnesses. The use of biologically integrated titanium cages of a unique design based on computer 3D modeling for the surgical treatment of patients with degenerative illnesses of the spine’s intervertebral discs has been proposed and experimentally tested. The goal of this study is to compare the radiographic and clinical outcomes of lumbar posterior interbody fusion with a 3D porous titanium alloy cage versus a titanium-coated polyetheretherketone (PEEK) cage, including fusion quality, time to fusion, preoperative and postoperative patient assessments, and the presence, severity, and other side effect characteristics. (1) Methods: According to the preceding technique, patients who were operated on with physiologically integrated titanium cages of a unique design based on 3D computer modeling were included in the study group. This post-surveillance study was conducted as a randomized, prospective, interventional, single-blind, center study to look at the difference in infusion rates and the difference compared to PEEK cages. The patients were evaluated using CT scans, Oswestry questionnaires (every 3, 6, and 12 months), and VAS scales. (2) Results: Six months following surgery, the symptoms of fusion and the degree of cage deflation in the group utilizing the porous titanium 3D cage were considerably lower than in the group using the PEEK cage (spinal fusion sign, p = 0.044; cage subsidence, p = 0.043). The control group had one case of cage migration into the spinal canal with screw instability, one case of screw instability without migration but with pseudoarthrosis formation and two surrounding segment syndromes with surgical revisions compared with the 3D porous titanium alloy cage group. (3) Conclusions: The technique for treating patients with degenerative disorders or lumbar spine instability with aspects of neural compression utilizing biologically integrated titanium cages of a unique design based on computer 3D printing from CT scans has been proven. This allows a new approach of spinal fusion to be used in practice, restoring the local sagittal equilibrium of the spinal motion segment and lowering the risk of pseudarthrosis and revision surgery.

The Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is an insect defoliator of the potato, Solanum tuberosum L. This species thrives in agricultural environments because of its flexible and complex life history, as well as its ability to evolve insecticide resistance. As a result, it has become a widely distributed agricultural pest. Ledprona (trade name Calantha) is a recently developed novel double-stranded RNA (dsRNA) insecticide that controls populations of Colorado potato beetle through RNA interference (RNAi). Previous studies have demonstrated the efficacy of ledprona through laboratory, greenhouse, and field studies. Colorado potato beetles from geographically distinct populations are known to vary in their response to insecticides, including experimental compounds based on RNAi. We tested the mortality and foliage consumption of beetles from different areas in the US treated with ledprona and found significant variation in both parameters. The beetles originating from New York were significantly less susceptible to ledprona in leaf disc assays compared to other populations. However, currently there is no evidence of reduced performance of ledprona against that population under field conditions, possibly because intoxicated beetles cannot withstand multiple stressors present in the field. The results of this study confirmed that the ledprona efficacy differs among geographically distinct populations, which may have implications for managing Colorado potato beetles.

ABSTRACT Larvae of black soldier flies, Hermetia illucens, are increasingly used for biological conversion of animal and plant wastes into ingredients of animal feeds on an industrial scale. The presence of pathogenic microorganisms in harvested larvae may be a serious problem for wide-scale adoption of this technology. Fortunately, black soldier fly larvae may have some antimicrobial properties. Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium associated with various environments that can be pathogenic to humans and farmed animals. We tested whether black soldier fly larvae suppress MRSA on potato substrate. Autoclaved potatoes containing black soldier fly larvae (P+BSFL), potatoes inoculated with MRSA and containing black soldier fly larvae (P+MRSA+BSFL), and potatoes inoculated with MRSA (P+MRSA) were incubated in glass jars. Substrate samples were taken after 3 and 7 days of incubation and plated on Trypticase soy agar (TSA) and Staphylococcus medium 110 agar (SA) to quantify total bacteria and MRSA, respectively. DNA was extracted from potato substrates on both days and sequenced to assess bacterial and fungal diversity using 515F/806R and internal transcribed spacer (ITS) 1/2 primers, respectively, and QIIME 2.0 software. Both total bacterial and MRSA-specific CFU were reduced in the presence of black soldier fly larvae, with a larger reduction for the latter. Twenty-five bacterial genera and 3 fungal genera were detected. Twenty bacterial genera were shared among the treatments and the days, but their relative abundances often varied. Among the most abundant genera, only Enterococcus and Lactococcus were universally present. Our findings confirm antimicrobial properties of black soldier fly larvae. IMPORTANCE Larvae of black soldier flies, Hermetia illucens, may be used to provide an environmentally sustainable and economically viable method for biological conversion of animal and plant wastes into ingredients of animal feeds on an industrial scale. However, contamination of harvested larvae by pathogenic microorganisms inhabiting decaying substrates may be a serious problem for wide-scale adoption of this technology. Fortunately, black soldier fly larvae may have some antimicrobial properties, including suppression of several common pathogens. Our study showed that such a suppression applies to methicillin-resistant Staphylococcus aureus, which is a ubiquitous bacterium pathogenic to animals (including humans).

Dickeya dianthicola (Samson) is an important pathogen causing blackleg disease of potato. Previous work suggested that insects might vector species of Pectobacteriaceae between plants but no conclusive work has confirmed this. Green peach aphids (Myzus persicae Sulzer) and Colorado potato beetles (Leptinotarsa decemlineata Say) are aggressive potato pests and related to known vectors of several species of bacteria other than D. dianthicola. This study sought to determine whether these insects vector D. dianthicola for potato infection. Neither insect species showed olfactory discrimination based on the presence of infection in laboratory tests but beetles were repelled by uninfected foliage treated with 2,3-butanediol, a primary Dickeya metabolite. Beetle recruitment to plants was not affected by their infection status; however, aphids preferred uninfected foliage when conspecifics were present. In the laboratory, neither insect acquired or transmitted D. dianthicola through feeding. In the field, neither insect’s abundance was significantly correlated with disease spread. Overall, this study did not find indications that D. dianthicola is vectored by the tested insect species. Therefore, efforts to limit Dickeya spread should focus on sanitation, water management, and seed screening—not on the control of these insect species.[Figure: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Bacillus cereus is a common and ubiquitous bacterium that can cause foodborne illnesses in humans and other animals. Common methods of contact between foodborne pathogens and their victims include exposure through contaminated food or food containment products. Using larvae of black soldier flies, Hermetia illucens, for biological conversion of wastes into components of animal feeds is a rapidly growing technology. However, contamination of larval biomass with pathogenic microorganisms may challenge its use on an industrial scale. We conducted laboratory experiments to test the effects of the black soldier fly larvae developing on simulated potato waste substrate on B. cereus abundance. We observed a general increase in the number of colony-forming units and concentration of hblD - gene when the larvae were present in the substrate, although the effect was modulated by larval densities and time since inoculation. It is possible that starch breakdown by black soldier fly larvae may provide a beneficial environment for B. cereus. Our results differ from the suppression in the presence by black soldier fly larvae reported for several other bacterial species and highlight the importance of taking proper food safety measures when using this technology.

Abstract Insecticidal double-stranded RNAs (dsRNAs) silence expression of vital genes by activating the RNA interference (RNAi) mechanism in insect cells. Despite high commercial interest in insecticidal dsRNA, information on resistance to dsRNA is scarce, particularly for dsRNA products with non-transgenic delivery (ex. foliar/topical application) nearing regulatory review. We report the development of the CEAS 300 population of Colorado potato beetle (Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) with > 11,100-fold resistance to a dsRNA targeting the V-ATPase subunit A gene after nine episodes of selection using non-transgenic delivery by foliar coating. Resistance was associated with lack of target gene down-regulation in CEAS 300 larvae and cross-resistance to another dsRNA target (COPI β; Coatomer subunit beta). In contrast, CEAS 300 larvae showed very low (~ 4-fold) reduced susceptibility to the Cry3Aa insecticidal protein from Bacillus thuringiensis. Resistance to dsRNA in CEAS 300 is transmitted as an autosomal recessive trait and is polygenic. These data represent the first documented case of resistance in an insect pest with high pesticide resistance potential using dsRNA delivered through non-transgenic techniques. Information on the genetics of resistance and availability of dsRNA-resistant L. decemlineata guide the design of resistance management tools and allow research to identify resistance alleles and estimate resistance risks.

Potato virus Y (PVY) is a non-persistent virus that is transmitted by many aphid species and causes significant damage to potato production. We constructed a spatially-explicit model simulating PVY spread in a potato field and used it to investigate possible effects of transmission efficiency, initial inoculum levels, vector behavior, vector abundance, and timing of peak vector activity on PVY incidence at the end of a simulated growing season. Lower PVY incidence in planted seed resulted in lower virus infection at the end of the season. However, when populations of efficient PVY vectors were high, significant PVY spread occurred even when initial virus inoculum was low. Non-colonizing aphids were more important for PVY spread compared to colonizing aphids, particularly at high densities. An early-season peak in the numbers of noncolonizing aphids resulted in the highest number of infected plants in the end of the season, while mid- and late-season peaks caused relatively little virus spread. Our results highlight the importance of integrating different techniques to prevent the number of PVY-infected plants from exceeding economically acceptable levels instead of trying to control aphids within potato fields. Such management plans should be implemented very early in a growing season.

Colorado potato beetle (CPB, Leptinotarsa decemlineata) is a major pest of potato and other solanaceous vegetables in the Northern Hemisphere. The insect feeds on leaves and can completely defoliate crops. Because of the repeated use of single insecticide classes without rotating active ingredients, many chemicals are no longer effective in controlling CPB. Ledprona is a sprayable double-stranded RNA biopesticide with a new mode of action that triggers the RNA interference pathway. Laboratory assays with second instar larvae fed Ledprona showed a dose–response where 25×10−6g/L of dsPSMB5 caused 90% mortality after 6days of initial exposure. We also showed that exposure to Ledprona for 6h caused larval mortality and decreased target messenger RNA (mRNA) expression. Decrease in PSMB5 protein levels was observed after 48h of larval exposure to Ledprona. Both PSMB5 mRNA and protein levels did not recover over time. Ledprona efficacy was demonstrated in a whole plant greenhouse trial and performed similarly to spinosad. Ledprona, currently pending registration at EPA, represents a new biopesticide class integrated pest management and insecticide resistance management programs directed against CPB.

Abstract Crop yield prediction is a critical measurement, especially in the time when parts of the world are suffering from farming issues. Yield forecasting gives an alert regarding economic trading, food production monitoring, and global food security. This research was conducted to investigate whether active optical sensors could be utilized for potato (Solanum tuberosum L.) yield prediction at the mid.le of the growing season. Three potato cultivars (Russet Burbank, Superior, and Shepody) were planted and six rates of N (0, 56, 112, 168, 224, and 280 kg ha−1), ammonium sulfate, which was replaced by ammonium nitrate in the 2nd year, were applied on 11 sites in a randomized complete block design, with four replications. Normalized difference vegetation index (NDVI) and chlorophyll index (CI) measurements were obtained weekly from the active optical sensors, GreenSeeker (GS) and Crop Circle (CC). The 168 kg N ha−1 produced the maximum potato yield. Indices measurements obtained at the 16th and 20th leaf growth stages were significantly correlated with tuber yield. Multiple regression analysis (potato yield as a dependent variable and vegetation indices, NDVI and CI, as independent variables) could make a remarkable improvement to the accuracy of the prediction model and increase the determination coefficient. The exponential and linear models showed a better fit of the data. Soil organic matter content increased the yield significantly but did not affect the prediction models. The 18th and 20th leaf growth stages are the best time to use the sensors for yield prediction.

Abstract Undesirable growth of potato (Solanum tuberosum L.) crop under an excessive N fertilizer application is the main obstacle presently. This research was conducted to investigate the response of different potato cultivars; Russet Burbank, Shepody, and Superior, and its qualitative characteristics under a series of N rates. Six rates of N fertilization (0–280 kg ha−1) were applied on 11 sites in a randomized complete block design, with four replications. Sites with ≥30 g kg−1 of soil organic matter (OM) produced total tuber yield, marketable yield, and tuber weight per plant 39.5, 45.2, and 54.9%, respectively, higher than sites with ≤30 g kg−1 of OM. Tubers specific gravity increased by 0.18% in the sites with ≥30 g kg−1 of OM. The total tuber yield for the three cultivars was maximized at 168 kg N ha−1. Marketable specific gravity, starch, and dry matter content were achieved by applying 168 and 112 kg N ha−1 at ≤30 and ≥30 g kg−1 of OM sites, respectively. Russet Burbank produced a higher yield than Shepody and Superior cultivars significantly, but there was no significant difference among them regarding specific gravity. Excessive N application (>168 kg ha−1) decreased potato tuber production and quality.

Engine selection for a specific type of transport vehicle, configuration and refinement of mathematical models of processes, improvement of engine construction are made based on the results of experimental research. However, in technical literature, and even the information resources of the manufacturers very limited information about the small engines can be found. In addition, the available data often contradicts each other. Goal of the arti-cle: experimental research of fuel efficiency and toxicity of exhaust gases of the small Briggs & Stratton Vanguard 18HP engine at different loads and speeds. Methodology. The engine performance parameters were evaluated on the experimental set-up of the internal combustion engines department of National Technical University "Kharkiv Polytechnic Institute". Characteristics of the engine on the modes with speeds 1800, 2400, 3000, 3600 rpm and loads from idle to maximum were obtained. As a result of experimental data processing volumetric efficiency and air/fuel ratios were determined. Total friction value of effective pressure was obtained by extrapo-lation the plot of fuel consumption versus brake out-put back to zero fuel consumption. Results. The impact of engine load and speed on the parameters of the fuel efficiency and emissions of the engine was analyzed. It is shown that the level of motoring losses in the small Briggs&Stratton Vanguard 18 HP en-gine corresponds to the motoring losses in gasoline engines with greater volume and speed. The empirical equation for determining total friction value of effective pressure in the engine was proposed. It is shown that formula proposed by V.G.Dyachenko provides satisfactory accuracy of determining total friction value of effective pressure. Originality of work consists in the proposed empirical dependence of total friction value of effective pressure on the engine speed for small engine. Рractical value is in the parameters of the small engine at operating speeds, the assessment of the applicability of the different empirical dependencies for evaluation of the motoring losses in the small engine.

This paper discusses the formulation of the problem of designing the cast parts block-crankcases engine in order to ensure its quality for the case study of cast iron parts of the cylinder block inline four-cylinder gasoline engine with the capacity of 1.4 dm3. Material Ch190B is gray cast iron with optional chemical composition, and sulfur – no more than 0.15 %, phosphorus – no more than 0.1 %, structure – perlite plate. The results obtained in this work confirm the conclusions about the possibility of reducing the metal content of the casting and changing the technical conditions of its manufacture. According to the results of the research, the developed recommendations are aimed at stabilizing the characteristics of the metal, reducing metal consumption, and changing the technical conditions for the defectiveness of this type of castings. Recommendations for changing the configuration of the partition in order to reduce the metal content of the casting and recommendations for changing the Technical Conditions for casting defects were stated for the casting block crankcase 4ChN12/14. For defects of discontinuity type, the maximum size was defined, and controlled places of their detecting were defined.

The Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is an insect defoliator of the potato, Solanum tuberosum L. This species thrives in agricultural environments because of its flexible and complex life history, as well as its ability to evolve insecticide resistance. As a result, it has become a widely distributed agricultural pest. Ledprona (trade name Calantha) is a recently developed novel double-stranded RNA (dsRNA) insecticide that controls populations of Colorado potato beetle through RNA interference (RNAi). Previous studies have demonstrated the efficacy of ledprona through laboratory, greenhouse, and field studies. Colorado potato beetles from geographically distinct populations are known to vary in their response to insecticides, including experimental compounds based on RNAi. We tested the mortality and foliage consumption of beetles from different areas in the US treated with ledprona and found significant variation in both parameters. The beetles originating from New York were significantly less susceptible to ledprona in leaf disc assays compared to other populations. However, currently there is no evidence of reduced performance of ledprona against that population under field conditions, possibly because intoxicated beetles cannot withstand multiple stressors present in the field. The results of this study confirmed that the ledprona efficacy differs among geographically distinct populations, which may have implications for managing Colorado potato beetles. [ABSTRACT FROM AUTHOR]