Promising Hybrid Research Articles

Fullerene-promoted organic-inorganic hybrid electrochemiluminescence biosensor for sensitive detection of concanavalin A

A fullerene-promoted organic-inorganic hybrid electrochemiluminescence (ECL) biosensor was proposed for sensitive detecting concanavalin A (ConA). Here, platinum-modified inorganic TiO2 (Pt-TiO2) promotes charge transfer to enhance ECL intensity of organic luminescent probe—ammonolysis product of PTCDA (PTC). Fullerene interacts with K2S2O8 co-reagent to produce more SO4•− free radicals, and its large specific-surface-area and electrophilic nature are beneficial to loading more luminescent PTC. The glucose oxidase (GOx) is chosen for specific recognition of ConA through a biospecific interaction. The constructed ECL biosensor shows a wide detection range of 1 × 10−4–1 × 103 ng mL−1 with a low detection limit (LOD) of 1.8 × 10−5 ng mL−1, as well as high stability, reproducibility, and detection capability of actual serum. This work provides a promising organic-inorganic hybrid biosensor platform for early biotherapy and clinical diagnosis.

Investigation of Oceanic Turbulence Random Phase Screen Generation Methods for UWOC

Underwater wireless optical communication (UWOC) has recently gained great research interest due to its capability of transmitting data underwater with high data rate and low latency. However, oceanic turbulence seriously degrades the optical signal quality and hence the performance of practical UWOC systems. Establishing more accurate and efficient phase screen models is in demand for studying the oceanic turbulence effect. In this paper, techniques for generating underwater random phase screens are studied and supplemented. A promising hybrid method combining sparse spectrum and Zernike polynomials methods is proposed and investigated, which generates phase screens with improved accuracy and efficiency.

Preserving the biodiversity of Iridaceae family representatives in the Subtropical Scientific Centre of RAS

This paper considers the issue of preserving biological diversity of Iridaceae family representatives in the FRC SSC of RAS. The research was carried out in the humid subtropical climate on the Black Sea coast of Krasnodar Territory. The objects of research were the following Iridaceae family representatives: Iris L., Crocus L., Gladiolus L., Freesia Eckl. ex Klatt, including cultivar samples from Russian and foreign breeding, as well as species of natural flora. Collectible samples are preserved and maintained in a living form, used both in scientific research, including introduction, breeding, technology, physiology and biochemistry, and for solving import substitution issues in such fields as floriculture and ornamental gardening. The paper presents data on grouping 358 Iris cultivar samples, including 35 cultivars bred by FRC SSC of RAS, as well as 139 promising hybrid forms, selected by the type of modified shoots (corms, bulbs, rhizomes). Iridaceae family representatives bloom from February to November in natural conditions and during the year when forced, they vary in plant height (from miniature to giant), can be used in landscaping (306 cultivar samples), as potted plants (74) and cut (259). In the course of the work carried out, it has been found that the climatic conditions of the research area are well suited for cultivation and scientific research on bulbotuberiferous, rhizomatous and bulbous plants from Iridaceae family, regardless of their origin and distribution area.

A novel hybrid bioprocess strategy addressing key challenges of advanced biomanufacturing.

Monoclonal antibodies (mAb) are commonly manufactured by either discontinuous operations like fed-batch (FB) or continuous processes such as steady-state perfusion. Both process types comprise opposing advantages and disadvantages in areas such as plant utilization, feasible cell densities, media consumption and process monitoring effort. In this study, we show feasibility of a promising novel hybrid process strategy that combines beneficial attributes of both process formats. In detail, our strategy comprises a short duration FB, followed by a fast media exchange and cell density readjustment, marking the start of the next FB cycle. Utilizing a small-scale screening tool, we were able to identify beneficial process parameters, including FB interval duration and reinoculation cell density, that allow for multiple cycles of the outlined process in a reproducible manner. In addition, we could demonstrate scalability of the process to a 5L benchtop system, using a fluidized-bed centrifuge as scalable media exchange system. The novel process showed increased productivity (+217%) as well as longer cultivation duration, in comparison to a standard FB with a significantly lower media consumption per produced product (-50%) and a decreased need for process monitoring, in comparison to a perfusion cultivation. Further, the process revealed constant glycosylation pattern in comparison to the perfusion cultivation and has strong potential for further scale-up, due to the use of fully scalable cultivation and media exchange platforms. In summary, we have developed a novel hybrid process strategy that tackles the key challenges of current biomanufacturing of either low productivity or high media consumption, representing a new and innovative approach for future process intensification efforts.

Влияние агротехнических приемов на урожайные свойства семян F1 гибрида подсолнечника Сурус

The field experiment was conducted in the experimental seed-growing farm “Berezanskoe”, Korenovsk district, Krasnodar region, on sowings of the promising sunflower hybrid Surus on leached chernozem of the Western Ciscaucasia. Plots placement is systematic, in three replications; plot square is 112 m2. The purpose of the research was to study effect of agrotechnical practices (fertilizer, chemical and biological plant protection against diseases) and seed-sowing rates (65 and 75 thousand pcs/ha) on a hybridization plot during cultivation of seeds F1 (2021) on yield and quality of commercial seeds in progeny (2022) of sunflower hybrid Surus planted with seed-sowing rates of 60 and 80 thousand pcs/ha. The agrotechnical practices applied on the hybridization plots did not influenced significantly on yield in progenies; also they did not effect the prevalence of downy mildew, rust, and bacterioses on sunflower plants. There was insignificant impact on an infection level of the sunflower plant with fusarium root rot, alternaria, and phoma rot that influence a little the crop yield. The highest yield in F1 – 3.21 t/ha – was stated in 2022 at seed-sowing rate of 60 thousand pcs/ha, in a variant where were used seeds obtained in 2021 at a seed-sowing rate of 75 thousand pcs/ha on a hybridization plot and fertilizers and chemical ways of plant protection were applied. Therefore, at sufficient water supply in soil, the seed-sowing rate of 60 thousand pcs/ha of F1 hybrid Surus considered to be scientifically proved as it allows obtaining high and stable yield and qualitative sunflower products in progenies. When fertilizers, chemical ways of plant protection and a seed-sowing rate of 75 thousand pcs/ha were applied on a hybridization plot in 2021, the highest net profit and profitability were obtained in 2022 at both seed sowing rates in F1 (60 and 80 thousand pcs/ha) – 35163 and 33933 RUR/ha, 78 and 75%, respectively.

MOLECULAR ASSESSMENT OF GENETIC DIVERGENCE AMONG MAIZE GENOTYPES

Research carried out in 2021 at the Jeser Al-Musayyab Company, Baghdad, Iraq, determined the molecular variations among 10 inbred lines of maize (Zea mays L.), for use in the future production of promising F1 hybrids. DNA sequencing random polymorphism technology using Inter Simple Sequence Repeats (ISSR) with five primers (UBC 834, UBC 835, UBC 856, UBC 866, and UBC 897) assessed the genetic variations among the 10 inbred lines of maize. All five primers produced 29 bands, averaging 5.8 strips each primer. The four primers, UBC 834, UBC 835, UBC 866, and UBC 897, had produced the same and highest number of proliferators with molecular weights ranging from 100 to 2000 bp. The primer UBC 856 showed the lowest number, with a molecular weight of 100–500 bp. The total number of polymorphs was 24, with a percentage of 82.4%, with the lowest (80%) polymorphs recorded in the primer UBC 856. The least discriminatory efficiency and ability values were 17.24% and 16.66%, respectively. Relying on binary data and genetic divergence using the UPGMA method to create a genetic kinship tree, the maize lines were separated into two groups, i.e., A, B, secondary, and sub-secondary groups. The highest genetic similarity (with the lowest genetic divergence) was estimated according to the Nei and Li coefficient of 0.23 between the two lines HS and S-10. The presented findings can provide further guidance and help analyze the genetic diversity among the maize populations.

Эффективность применения агроприемов на участке гибридизации подсолнечника для улучшения физико-механических и биологических свойств выращиваемых семян

Influence of agrotechnical practices on biological, physical and mechanical qualities of seeds produced on a hybridization plot of the promising sunflower hybrid Surus was studied. To reach a goal we used a complex of agrotechnical practices (seed-sowing rates, fertilizers, chemical and biological plant protective means against diseases and pests) which had different levels of efficiency on the improvement of the biological, physical and mechanical qualities of the produced seeds. To improve the biological qualities of seeds, we graded the seeds into three different fractions: large, middle, and small. This resulted the seeds became more uniform by size, weight, volume weight, and had the higher laboratory germination. Output of a small fraction (size ˂ 3.0 mm) was 38%, a middle one (size 3.0–3.2 mm) – 37, and a large one (size ˃ 3.2 mm) – 25%, and 1000 seed weight by variants of an experiment within 40–41 g of small fraction, 46–48 – middle, and 50–52 g of large one. An average 1000 seed weight by all variants of the experiment and seed-sowing rates of the small fraction of seeds was 40 g, middle one was 47 g, and large one was 51 g. The grading of seeds by physical qualities within their linear sizes caused increasing of the laboratory germination of small seeds higher the level (85%) prescribed by the State Standard of Russia 52325-2005 in variants with chemical and biological plant protection against pests and diseases. The germination of the selected middle seed fraction was the highest (91%) in all variants of the experiment compared to the other two fractions. In a large seed fraction, there were no certified seeds by the germination. Therefore, grading the seeds by fractions is the effective method of selection and uniforming them by physical and mechanical, and biological qualities that as a result can positively effect on yield and quality of commercial seeds in progenies.

Optimization Approaches for Demand-Side Management in the Smart Grid: A Systematic Mapping Study

Demand-side management in the smart grid often consists of optimizing energy-related objective functions, with respect to variables, in the presence of constraints expressing electrical consumption habits. These functions are often related to the user’s electricity invoice (cost) or to the peak energy consumption (peak-to-average energy ratio), which can cause electrical network failure on a large scale. However, the growth in energy demand, especially in emerging countries, is causing a serious energy crisis. This is why several studies focus on these optimization approaches. To our knowledge, no article aims to collect and analyze the results of research on peak-to-average energy consumption ratio and cost optimization using a systematic reproducible method. Our goal is to fill this gap by presenting a systematic mapping study on the subject, spanning the last decade (2013–2022). The methodology used first consisted of searching digital libraries according to a specific search string (104 relevant studies out of 684). The next step relied on an analysis of the works (classified using 13 criteria) according to 5 research questions linked to algorithmic trends, energy source, building type, optimization objectives and pricing schemes. Some main results are the predominance of the genetic algorithms heuristics, an insufficient focus on renewable energy and storage systems, a bias in favor of residential buildings and a preference for real-time pricing schemes. The main conclusions are related to the promising hybridization between the genetic algorithms and swarm optimization approaches, as well as a greater integration of user preferences in the optimization. Moreover, there is a need for accurate renewable and storage models, as well as for broadening the optimization scope to other objectives such as CO2 emissions or communications load.

Using KNbO3 catalyst produced from a simple solid-state synthesis method in a new piezophotocatalytic ozonation hybrid process

The present work reports the development and application of potassium niobate (KNbO3) as a catalyst in a novel hybrid piezophotocatalytic ozonation process aimed at wastewater remediation. Pure KNbO3 samples were produced through a simple solid-state synthesis using water-soluble ammonium niobate (V) oxalate hydrate (C4H4NNbO9·xH2O) as niobium source, employing different potassium precursors (KNO3, K2CO3, KOH, and C8H5KO4). The synthesis was also carried out using powdered niobium oxide as a precursor, aiming to evaluate the differences between the niobates obtained. The results achieved in this study show that all the niobates produced using ammonium niobate (V) oxalate hydrate were composed solely of the orthorhombic structure of KNbO3, while the materials synthesized using niobium oxide exhibited the rhombohedral structure of KNbO3 along with niobium-rich potassium niobates (K3Nb8O21, K2Nb4O21, and KNb3O8) and residual niobium oxide. This behavior was attributed to the enhanced chemical homogeneity derived from the synthesis using ammonium niobate (V) oxalate hydrate, which facilitated the reaction between the components during the thermal treatment step. Furthermore, the optical and morphological properties of the niobates were considerably influenced by the application of different potassium salts. Owing largely to its morphological and electrical properties, the material synthesized using potassium hydrogen phthalate displayed the highest photocatalytic activity in terms of methylene blue discoloration among the niobates produced using C4H4NNbO9·xH2O. Finally, the proposed piezophotocatalytic ozonation process was found to be a highly efficient strategy for the discoloration of methylene blue, as it successfully harnessed the synergy between the multiple mechanisms involving active radical generation toward the development of a highly promising hybrid advanced oxidation process.

Accumulation and morphological properties of starch in tubers of new potato hybrids

The article presents the results of studying potato accessions according to the accumulation and morphological properties of starch in tubers in the nursery of dynamic testing in agroecological conditions of the Kirov region (Volga-Vyatka region) in 2022. The objects of the research were 11 new hybrids bred by the Falenki Breeding Station – branch of the Federal Agricultural Research Center of the North-East named N.V. Rudnitsky. The early-maturing variety Udacha, the middle-early variety Nevsky, and the mid-season variety Chaika were used as standards. There have been identified hybrids with increased starch content (19 % and higher) on the 80th day of vegetation: early-maturing 172-13, medium-early – 165-00, 27-07, 13-18, mid-season – 182-13, 580-13, 252-18. The hybrids of the middle early group had the largest average size of starch grains: 165-00 (34.3±2.6 microns), 132-18 (36.0±3.0 microns), 233-12 (39.2±3.3 microns). Most of the hybrids had starch grains of regular rounded shape, accessions 233-12 and 232-12 – mostly irregular (angular) shape. In the course of the research, it was found that storing potatoes at the temperature of 3...4 ° C led to a decrease in the fraction of starch grains of very large size: in early-maturing varieties from 9.2 to 2.7 %, in middle early – from 13.5 to 5.0 %, in mid-season – from 9.6 to 3.2 %, which was due to starch resynthesis. As a result of the breeding work, promising potato hybrids of various maturation periods have been identified for transfer to state variety testing with improved agronomic traits, including high potential productivity: early-maturing 172-13, middle-early 233-12, mid-season 182-13 and 580-13.

A case study of potato germplasm enhancement using distant late blight resistant wild relatives

AbstractImproving potato late blight (LB) resistance is essential for ensuring food security, particularly using wild relatives endemic to Phytophthora infestans‐prone regions. However, reproductive barriers can impede the transfer from potato wild relatives (PWR) to the cultivated genepool. This study sought to incorporate potentially novel LB resistance from wild diploid accessions of Series Piurana (Solanum chiquidenum, Solanum paucissectum, and Solanum piurae), Tuberosa (Solanum cajamarquense), and Megistracroloba (Solanum sogarandinum) into tetraploid potato. Trough rescue pollination, 699 diploid interspecific hybrids were obtained, of which 385 displayed LB resistance in two endemic environments. Based on a comprehensive evaluation, including assessing 2n pollen production, 14 diploid interspecific hybrids were selected to continue the introgression process. These pre‐bred stocks were then used in interploidy (4x‐2x) crosses to incorporate their LB resistance in the cultivated tetraploid background. Assessment of 1978 genotypes resulting from interploidy crosses under endemic disease pressure yielded 717 hybrids with moderate to high levels of LB resistance. Evaluation of pollen viability and ploidy revealed moderate fertility and predominantly tetraploid genotypes. Reassessment of LB resistance on this new subset of hybrids further identified 214 genotypes with sustained resistance. Among them, 12 tetraploid hybrids with low glycoalkaloid content, favorable agronomic, and post‐harvest attributes were identified as crossing‐friendly stocks. Notably, 11 of these hybrids were derived from S. cajamarquense and one from S. sogarandinum. These promising 4x hybrids are now primed to be incorporated into potato breeding programs.

Constructing CdIn2S4/ZnS type-I band alignment heterojunctions by decorating CdIn2S4 on ZnS microspheres for efficient photocatalytic H2 evolution

In this study, a series of promising binary hybrid heterojunction CdIn2S4/ZnS (CIS/ZnS) were constructed via a facile hydrothermal method. Credible characterization methods including powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–vis diffuse reflectance spectra (DRS) were carried out to investigate the physicochemical properties the as-obtained photocatalysts. Photocatalytic water splitting for hydrogen evolution was performed to evaluate the photocatalytic activity of the photocatalyst. The results indicate that the light-harvesting ability could be markedly enhanced by decorating CdIn2S4 on ZnS microspheres. Compared with the pristine CdIn2S4 and ZnS, the hybrid photocatalysts present more efficient photocatalytic hydrogen production performance. Among composite photocatalysts, the 5% CIS/ZnS sample manifests the highest photocatalytic hydrogen production rate of 10.80 mmol g−1 h−1, which is 2.6 and 5.4 times higher than that of ZnS and CdIn2S4, respectively. Moreover, a type-I band alignment mechanism was prudently put forward to interpret the photocatalytic hydrogen generation activity. The boosted photocatalytic hydrogen evolution activities of CIS/ZnS can be attributed to the enhanced light-harvesting ability, efficient separation and transfer of the photo-induced charge carriers, and inhibition of electrons and holes recombination of binary hybrid CIS/ZnS photocatalysts.

Synthesis and Characterization of Inorganic-Organic Derivatives of Layered Perovskite-like Niobate HSr2Nb3O10 with n-Amines and n-Alcohols.

A protonated and hydrated Dion-Jacobson-phase HSr2Nb3O10∙yH2O was used to prepare two series of inorganic-organic derivatives containing non-covalently intercalated n-alkylamines and covalently grafted n-alkoxy groups of different lengths, as they are promising hybrid materials for photocatalytic applications. Preparation of the derivatives was carried out both under the conditions of standard laboratory synthesis and by solvothermal methods. For all the hybrid compounds synthesized structure, quantitative composition, a type of bonding between inorganic and organic parts as well as light absorption range were discussed using powder XRD, Raman, IR and NMR spectroscopy, TG, elemental CHN analysis, and DRS. It was shown that the inorganic-organic samples obtained contain approximately one interlayer organic molecule or group per proton of the initial niobate, as well as some amount of intercalated water. In addition, the thermal stability of the hybrid compounds strongly depends on the nature of the organic component anchoring to the niobate matrix. Although non-covalent amine derivatives are stable only at low temperatures, covalent alkoxy ones can withstand heat up to 250 °C without perceptible decomposition. The fundamental absorption edge of both the initial niobate and the products of its organic modification lies in the near-ultraviolet region (370-385 nm).

Breeding work on new potato genotypes under the conditions of Primorsky Kray

Relevance. Potato is one of the most important agricultural crops used for various purposes. Its tubers are an essential food product for many people worldwide. The development of breeding technologies and an accelerated marketing of new promising potato genotypes play a significant role in the industry of potato production today. FSBSI “FSC of Agricultural Biotechnologies of the Far East named after A.K. Chaiki” conducted a complex study on potato hybrids.The research goal was to evaluate and select promising potato hybrids with high yield, marketability, and resistance to the most dangerous diseases. The experiments were carried out in our breeding nurseries located at Putsilovka v., Ussuriysk district, in the Kazachka river valley. Hybrids Purple potato × Manifest and (Aspiya×Qusto) × Manifest were used as the research object. The methodology of FSBSI “N. I. Vavilov All-Russian Institute of Plant Genetic Resources” and FSBSI “Russian Potato Research Center” were employed for the trials of the material. Fifty-two potato varieties from different maturity groups were used as pollen sources.Results. As the result, seventy-one hybrid combinations were created, 2272 flowers were pollinated, and 640 potato fruits were obtained. The efficiency of the crossing was 28.2%. Hybrids Pri15-12-23 Purple potato × Manifest and Pri-15-15-7 (Aspiya×Qusto) × Manifest had the highest rate of potato fruit formation. These accessions were characterized by good taste and high yield (48.7-51.0 t/ha), starch content (13.9-16.3 %), and vitamin C (15.0-15.4 mg/100 g). Tubers of these genotypes were oblong-oval or round with yellow flesh and small eyes. The studied accessions showed resistance to the main plant pathogens of the Russian Far East. Currently the obtained genotypes are tested for resistance to potato wart disease (S. Endobioticum, Dahlem pathotype) in the State variety trials. These accessions generate significant interest for breeding.

Performance of Tomato Hybrids Arka Abhed and Arka Samrat in Visakhapatnam District of Andhra Pradesh, India

The farmers of Visakhapatnam district were in a great need of best performing and high yielding tomato variety as the existing varieties are less yielders and highly succumb to pests and diseases. An On-Farm Trial (OFT) for three consecutive years (2020-21, 2021-22) was conducted by ICAR- ANGRAU, Krishi Vigyan Kendra, Kondempudi directly in the farmers’ fields of five selected villages viz. Bangurumeta, Adduru, Thotakurapalem, Pottidorapalem, Jaithavaram and Chedikada in Visakhapatnam district of Andhra Pradesh to evaluate the performance of two very promising tomato hybrids viz. Arka Abhed and Arka Samrat with regard to yield and economic analysis vis a vis the farmers’ practice variety Laxmi. A total of twenty-five farmers actively participated in the OFT covering an area of 7.5 acres. As regards fruit yield, the tomato hybrid Arka Abhed proved to be the best followed by Arka Samrat and Laxmi hybrid for all the three years of the study with fruit yields of 587.32, 569.13 and 409.14 q/ha, respectively. During the years of the trial, the fruit yields of Arka Abhed and Arka Samrat improved from 27.44 to 30.33% and 24.57 to 28.11%, respectively. Average cost-benefit ratios for three years for Arka Abhed, Arka Samrat and Laxmi hybrid were 1:2.30, 1:2.16 and 1:1.58, respectively. The Extension gap was between 111.18 to 183.86 and 129.08 to 202.83 q/ha for Arka Samrat and Arka Abhed, respectively. Results on Technology Index viz. 15.25, 19.47 and 28.83% for Laxmi (farmers’ practice), Arka Abhed and Arka Samrat, respectively, revealed that for both the tomato hybrids, there is viability of the demonstrated technology in the area of the OFT viz. Visakhapatnam district and the surrounding areas of north coastal Andhra Pradesh.

Design and evaluation of electrospun nylon 6/Zn-doped hydroxyapatite scaffold for lysozyme protein absorption

This study focused on the design and fabrication of a hybrid electrospun scaffold of nylon 6 (N6)/Zn-doped hydroxyapatite (ZH) nanoparticles for the absorption of lysozyme (LYZ) protein. The effects of electrospinning parameters were investigated by the central composite design method to introduce a roadmap to synthesize a promising hybrid electrospun polymer/ceramic scaffold for protein absorption. A quadratic model based on the coded factors indicated that the concentration of the electrospinning solution was the most effective parameter on the morphology and microstructure of the electrospun scaffold among the other parameters namely distance of needle to the collector, high voltage, and flow rate. The results of the suggested model were evaluated by SEM and TEM microscopies, and it was found that the model was also valid in the actual conditions. The practical hybrid scaffold was electrospun via 16.58 kV high voltage, 0.34 mL.h−1 flow rate, 12.44 cm distance, 17.21 wt.% of N6, and 2.13 wt.% of ZH. Furthermore, the kinetics of LYZ protein adsorption by pristine and hybrid electrospun scaffolds was studied. The results showed that the incorporation of Zn-doped HAp into N6 scaffolds could enhance the ability of protein adsorption 1.5 times more than the pristine N6 scaffold.

Hybrid Cryogels with Superabsorbent Properties as Promising Materials for Penicillin G Retention

This present study describes the investigation of new promising hybrid cryogels able to retain high amounts of antibiotics, specifically penicillin G, using chitosan or chitosan–biocellulose blends along with a naturally occurring clay, i.e., kaolin. In order to evaluate and optimize the stability of cryogels, three types of chitosan were used in this study, as follows: (i) commercial chitosan; (ii) chitosan prepared in the laboratory from commercial chitin; and (iii) chitosan prepared in the laboratory from shrimp shells. Biocellulose and kaolin, previously functionalized with an organosilane, were also investigated in terms of their potential to improve the stability of cryogels during prolonged submergence under water. The organophilization and incorporation of the clay into the polymer matrix were confirmed by different characterization techniques (such as FTIR, TGA, SEM), while their stability in time underwater was investigated by swelling measurements. As final proof of their superabsorbent behavior, the cryogels were tested for antibiotic adsorption in batch experiments, in which case cryogels based on chitosan extracted from shrimp shells seem to exhibit excellent adsorption properties for penicillin G.

Evaluation of the Immune Response to Chitosan-graft-poly(caprolactone) Biopolymer Scaffolds.

Biomimetic scaffolds recreating key elements of the architecture and biological activity of the extracellular matrix have enormous potential for soft tissue engineering applications. Combining appropriate mechanical properties with select biological cues presents a challenge for bioengineering, as natural materials are most bioactive but can lack mechanical integrity, while synthetic polymers have strength but are often biologically inert. Blends of synthetic and natural materials, aiming to combine the benefits of each, have shown promise but inherently require a compromise, diluting down favorable properties in each polymer to accommodate the other. Here, we electrospun a material comprising chitosan, a natural polysaccharide, and polycaprolactone (PCL), one of the most widely studied synthetic polymers used in materials engineering. In contrast to a classical blend, here PCL was chemically grafted onto the chitosan backbone to create chitosan-graft-polycaprolactone (CS-g-PCL) and then combined further with unmodified PCL to generate scaffolds with discreet chitosan functionalization. These small amounts of chitosan led to significant changes in scaffold architecture and surface chemistry, reducing the fiber diameter, pore size, and hydrophobicity. Interestingly, all CS-g-PCL-containing blends were stronger than control PCL, though with reduced elongation. In in vitro assessments, increasing the CS-g-PCL content led to significant improvements in in vitro blood compatibility compared to PCL alone while increasing fibroblast attachment and proliferation. In a mouse subcutaneous implantation model, a higher CS-g-PCL content improved the immune response to the implants. Macrophages in tissues surrounding CS-g-PCL scaffolds decreased proportionately to the chitosan content by up to 65%, with a corresponding decrease in pro-inflammatory cytokines. These results suggest that CS-g-PCL is a promising hybrid material comprising natural and synthetic polymers with tailorable mechanical and biological properties, justifying further development and in vivo evaluation.

Melanin and Polypyrrole-Coated Nanocellulose Hydrogel Networks for Environmental Sensing and Energy Storage

Melanins are black-brown pigments of a specific class of poly indolequinones found in nature and in the human body. They are responsible for photoprotection, radical scavenging, and metal ion chelation. Recently, there has been significant interest in eumelanin as a functional material due to its macromolecular structure and the exploitation of the quinone-hydroquinone redox equilibrium. While eumelanin can be used in many promising applications, it is insoluble in most solvents, limiting its processing into homogeneous materials and coatings. A promising approach is to use a carrier system to stabilize eumelanin by incorporating cellulose nanofibrils (CNFs), a nanoscopic material that originates from plant biomass. In this work, a flexible network consisting of CNFs coupled with vapor-phase polymerized conductive polypyrrole (PPy) is utilized to form a functional eumelanin hydrogel composite (MelaGel) for environmental sensing and battery applications. Flexible sensors for detecting pH or metal ions made from MelaGel can detect both pH values in a range from 4 to 10 and metal ions like zinc(II), copper(II), and iron(III), paving the way for environmental and biomedical sensor applications. The reduced internal resistance in the MelaGel leads to improved charge storage ability compared to synthetic eumelanin composite electrodes. Other noteworthy advantages of the MelaGel are the amphiphilic nature of PPy and the additionally offered redox centers. Lastly, this material was tested in aqueous electrolyte zinc coin cells, where it was shown to have charge/discharge stability for over 1200 cycles, showcasing this MelaGel composite as a promising eumelanin-based composite hybrid sensor/energy storage material.

Influence of plant density on productivity and quality indicators of sunflower oilseeds

In the agricultural technology of sunflower cultivation, plant density in crops is one of the main conditions that determine its further productivity [5]. The optimal sowing density of sunflower can vary widely and depend on various factors, such as the varietal characteristics of plant, the soil-climatic zone of its cultivation, specific weather conditions and, above all, the moisture supply of plants, especially in the critical phases of sunflower development (flowering and grain filling) [ 8]. It has been proved that the optimal plant density in sunflower crops is such that not only normal growth processes and development of each plant are ensured, but the maximum possible productivity per unit of sown area is also formed. In this regard, in 2018–2020, in the flat zone on the leached chernozems of LLC «Zarya» of the Shovgenovsky district of the Republic of Adygea, studies were carried out (according to B.A. Dospekhov «Methodology of field experience») in order to study the reaction of new promising sunflower hybrids (Gorstar, Natali, Iren, selection of Federal State Budgetary Scientific Institution «FSC «VNIIMK named after V.S. Pustovoit», Krasnodar) to change the number of plants per hectare. As a result of the research, the degree of influence of the studied factor on the formation of productive qualities of the studied sunflower hybrids has been established– the diameter of the anthode, the number of oil seeds in it, the mass of achenes from one anthode, the weight of 1000 achenes, the fulfillment of achenes, seed yield, total collection of oil from one hectare area). The studies have shown that the maximum seed yield has been achieved in the hybrids Gorstar and Iren, formed on the second variant (50 thousand pieces/ha). In the Natalie hybrid, the maximum yield was recorded in the variant with a plant density of 60 thousand pieces/ha. From this, it should be noted that with the option of 50 thousand pieces/ha, the Natali hybrid turned out to be 0.62–0.61 t/ha less productive than the Gorstar hybrid and 0.52–0.56 t/ha than the Irene hybrid.The studies were carried out on the equipment of the «Expert» Common Use Center of FSBEI HE «MSTU».