Hasil untuk "Biotechnology"

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DOAJ Open Access 2025
Electrical detection of emergent magnetization dynamics in artificial spin ice

Hitoshi Kubota, Sumito Tsunegi, Shingo Tamaru et al.

Artificial spin ices (ASIs) consisting of 72 stadium-shaped magnetic tunnel junction (MTJ) cells arranged in a honeycomb lattice were fabricated. The magnetization state of each cell was electrically detected using magnetoresistance. Measurements on the MTJ-based ASIs with a lattice constant a ranging from 980 nm to 2 μm confirmed the following: (1) the switching field of the cells depends on the angle of the long axis of the cell with respect to the field direction, reflecting the shape anisotropy of the free layer in the MTJ cells; (2) the switching field distribution was ∼10% of the mean value; and (3) the magnetic coupling increased monotonically with the reduction in a and reached ∼1 mT for the smallest a, which was close to the switching field distribution. Furthermore, during the magnetization of this ASI, reversed cells aligned in a string appeared, corresponding to the dipole strings previously reported for ASIs fabricated with single-layer ferromagnetic films. The appearance of a dipole string connecting emergent monopoles is a feature of the ASI dynamics. The observation of such emergent dynamics in the ASIs microfabricated using MTJ arrays highlights their potential for advancing the development of novel functional devices.

Biotechnology, Physics
DOAJ Open Access 2025
Estimating unreported SARS-CoV-2 infections in Austria using wastewater-based epidemiology

Simon D. Lindner, Herbert Oberacher, Karin Weyermair et al.

Wastewater-based epidemiology offers a comprehensive yet cost-effective way to monitor pathogen circulation. However, it is not entirely clear how wastewater signals can be reliably mapped to case numbers and therefore to incidence. Here, we aim to estimate the number of total SARS-CoV-2 infections including reported and unreported cases in Austria by analysing two different longitudinal wastewater datasets covering 113 wastewater treatment plants from October 2021 to October 2022. These plants cover most of the Austrian population, which had one of the highest per capita testing rates during the Coronavirus Disease 2019 (COVID-19) pandemic. We empirically find that the relationship between reported COVID-19 cases and viral load in wastewater is significantly influenced by the number of tests performed. Based on this observation, we developed a method for estimating total cases by scaling reported cases by test activity and accounting for periods when different viral variants were dominant. We find that the ratio of estimated total to reported cases increased substantially over time, from a value around 1.49 at the peak of the BA.2 wave to a value of 5.48 at the peak of the BA.5 wave, and validate these results in two datasets. Our results also suggest that there was less shedding per case in periods where BA.5 was dominant than in periods where BA.1 and BA.2 were dominant, which in turn showed less shedding than in periods dominated by the Delta variant. The results of this study provide critical insight into the potential of wastewater measurements to provide a more accurate assessment of the dynamics of infectious disease transmission.

Science (General), Social sciences (General)
DOAJ Open Access 2024
Long-term comparison of two β-TCP/PLCL composite scaffolds in rabbit calvarial defects

Hanna Pihlman, Jere Linden, Kaarlo Paakinaho et al.

Improving bone-graft substitutes and expanding their use in orthopedic and spinal surgery leads to shorter surgical times, fewer complications, and less pain among patients both in human and veterinary medicine. This study compared an elastic porous β-tricalcium phosphate/poly(L-lactide-co-ε-caprolactone) (β-TCP/PLCL) copolymer scaffold (composite scaffold) and a commercially available β-TCP/PLCL bone-graft substitute (chronOS Strip) in a rabbit calvarial defect. A bilateral, 12-mm circular defect was created in the parietal bones of 12 rabbits. Both graft materials were soaked in bone marrow aspirate before implantation, and the usability of the material was recorded during surgery. After a follow-up time of 24 ( n  = 5) and 48 ( n  = 7) weeks, artificial intelligence- (AI-) assisted micro-CT imaging was used to evaluate the bone formation and β-TCP distribution. Bone formation, implant material decomposition, and tissue reactions were further investigated through histopathology and AI-assisted histomorphometric analyses. Both materials supported tissue ingrowth and vascularization and modest 10%–16% new bone formation through the implant. In both materials the degradation advanced during the follow-up time, but there was implant material visible 48 weeks after implantation. Typical long term foreign body reaction with histiocytes, giant cells and lymphocytes, was seen in both materials being more pronounced in composite scaffold. The benefit of the new composite scaffold was its superior usability during surgery.

DOAJ Open Access 2024
Sustainable Composting of Vegetable Waste, Cow Dung, Grasses, and Food Wastes into Soil Amendment using Starter Culture and Growth Characteristics in Guava Plant

Selvaraj Arokiyaraj, Rajagopal Rajakrishnan, Subhanandaraj Russalamma Flanetraj

The study aim was to optimise the C/N ratio, improve the compost quality, reduce pathogenic bacteria load in the compost, and improve guava yield. Vegetable wastes were mixed with cow dung, grasses, and food wastes in ratios of 4:3:2:1 (w/w) for achieving a C/N ratio of approximately 37. Co-composting is an important strategy because the mixture of bulking agents can help achieve optimal composting conditions. Experimental results were obtained from a pilot-scale rotary drum reactor with forced aeration. In the reactor, the temperature increased during the thermophilic phase (58±2 °C) and decreased after 10 days (54±2 °C). The pH values moderately increased, then decreased, and were near to neutral after maturation. The results indicated that co-composting of bio-wastes at a C/N ratio of 37.6%±1.02% could be effectively decomposed to reduce the residuals to just 13.6%±1.05% after 28 days. The microbial population increased in both mesophilic and thermophilic stages and decreased at the end of the composting, reflecting stability. The stable compost was applied to the growth of guava plant, and the yield was calculated. The organic compost improved plant growth, fruit yield, and enriched phytochemical compounds in the fruit and peels. The phytochemical compounds improved antioxidant activity in the guava fruits.

Biotechnology
DOAJ Open Access 2024
Improving Respiratory Infection Diagnosis with Deep Learning and Combinatorial Fusion: A Two-Stage Approach Using Chest X-ray Imaging

Cheng-Tang Pan, Rahul Kumar, Zhi-Hong Wen et al.

The challenges of respiratory infections persist as a global health crisis, placing substantial stress on healthcare infrastructures and necessitating ongoing investigation into efficacious treatment modalities. The persistent challenge of respiratory infections, including COVID-19, underscores the critical need for enhanced diagnostic methodologies to support early treatment interventions. This study introduces an innovative two-stage data analytics framework that leverages deep learning algorithms through a strategic combinatorial fusion technique, aimed at refining the accuracy of early-stage diagnosis of such infections. Utilizing a comprehensive dataset compiled from publicly available lung X-ray images, the research employs advanced pre-trained deep learning models to navigate the complexities of disease classification, addressing inherent data imbalances through methodical validation processes. The core contribution of this work lies in its novel application of combinatorial fusion, integrating select models to significantly elevate diagnostic precision. This approach not only showcases the adaptability and strength of deep learning in navigating the intricacies of medical imaging but also marks a significant step forward in the utilization of artificial intelligence to improve outcomes in healthcare diagnostics. The study’s findings illuminate the path toward leveraging technological advancements in enhancing diagnostic accuracies, ultimately contributing to the timely and effective treatment of respiratory diseases.

Medicine (General)
DOAJ Open Access 2024
Role of bioproducts in the improvement of soybean productivity

Syrmolot Oksana, Telichko Ol’ga, Belova Tat’yana et al.

The paper studies the influence of bioproducts on soybean plants under the conditions of Primorsky kray. The research was conducted on released soybean variety Primorskaya 86. The research evaluates the efficacy of bioproducts Biocomposite correct, Rhizoform + Static, and plant biostimulator Biosteam Start. The variant with inoculant Rhizoform + Static (seed treatment) had 20% efficacy against Septoria blight. The highest biological efficacy (50.8%) against downy mildew was observed in the variant with Biocomposite-correct and biostimulator Biosteam Start + foliar treatment with Biocomposite-correct. The studied products had a positive effect on the morphometric characteristics of soybean plants. The maximum gain in plant height was noted in the variant with Rhizoform + Static (48.3 cm) at the flowering stage compared to the control (33.2 cm). Using the products increased the number of nodules relative to the control (56.9 pcs.). The highest number of nodules was observed after seed treatment with Rhizoform + Static (77.6 pcs.). The largest grains formed after seed treatment with Rhizoform + Static (203.3 g) (the TKW was 159.4 g in the control variant). Biological yield varied from 3.3 t/ha (seed treatment with Biocomposite-correct + seed treatment with Biosteam Start + foliar treatment with Biocomposite-correct) to 3.8 t/ha (seed treatment with Rhizoform + Static) among variants compared to 2.5 t/ha in the control. The research results allowed us to conclude that the studied bioproducts and biostimulator were effective in increasing the productivity of soybean plants.

Environmental sciences
DOAJ Open Access 2022
Shock Waves Enhance Expression of Glycosphingolipid Tumor Antigen on Renal Cell Carcinoma: Dynamics of Physically Unmasking Hidden Intracellular Markers Independent of Gene-Signaling Pathways

Nushin Hosano, Zahra Moosavi-Nejad, Makoto Satoh et al.

Antigens associated with tumors have proven valuable in cancer immunotherapy. Their insufficient expression in the majority of tumors, however, limits their potential value as therapeutic markers. Aiming for a noninvasive approach applicable in clinical practice, we investigated the possibility of using focused shock waves to induce membrane expression of hidden intracellular tumor markers. Here, we studied the in vitro effect of a thousand focused shock waves at 16 MPa overpressure on the membrane expression of a cytosolic glycosphingolipid, monosialosyl-galactosyl-globoside (MSGG). Double-staining flow cytometry with propidium-iodide and monoclonal antibody RM1 revealed an immediate increase in MSGG expression on renal carcinoma cells (18% ± 0.5%) that reached its peak value (20.73% ± 0.4%) within one hour after the shock waves. The results of immunoelectron microscopy confirmed the incorporation of MSGG into newly formed cytosolic vesicles and their integration with the cell membrane. Based on the enzymatic nature of MSGG production that is not controlled directly by genes, the immediate upregulation of MSGG membrane expression implies that a chain of mechanochemical events affecting subcellular structures are responsible for the shock-wave-induced antigenic modification. Physically unmasking hidden tumor antigens and enhancing their expression by focused shock waves presents a potential noninvasive method of boosting tumor immunogenicity as a theranostic strategy in cancer immunotherapy.

Biology (General)
DOAJ Open Access 2022
In Silico Study of Mercury Resistance Genes Extracted from Pseudomonas spp. Involved in Bioremediation: Understanding the Promoter Regions and Regulatory Elements

Duguma Dibbisa, Gobena Wagari

Microbial genes and their product were diverse and beneficial for heavy metal bioremediation from the contaminated sites. Screening of genes and gene products plays a significant role in the detoxification of pollutants. Understanding of the promoter region and its regulatory elements is a vital implication of microbial genes. To the best of our knowledge, there is no in silico study reported so far on mer gene families used for heavy metal bioremediation. The motif distribution was observed densely upstream of the TSSs (transcription start sites) between +1 and -350 bp and sparsely distributed above -350 bp, according to the current study. MEME identified the best common candidate motifs of TFs (transcription factors) binding with the lowest e value (7.2e-033) and is the most statistically significant candidate motif. The EXPREG output of the 11 TFs with varying degrees of function such as activation, repression, transcription, and dual purposes was thoroughly examined. Data revealed that transcriptional gene regulation in terms of activation and repression was observed at 36.4% and 54.56%, respectively. This shows that most TFs are involved in transcription gene repression rather than activation. Likewise, EXPREG output revealed that transcriptional conformational modes, such as monomers, dimers, tetramers, and other factors, were also analyzed. The data indicated that most of the transcriptional conformation mode was dual, which accounts for 96%. CpG island analysis using online and offline tools revealed that the gene body had fewer CpG islands compared to the promoter regions. Understanding the common candidate motifs, transcriptional factors, and regulatory elements of the mer operon gene cluster using a machine learning approach could help us better understand gene expression patterns in heavy metal bioremediation.

DOAJ Open Access 2022
Postharvest Ultraviolet Radiation in Fruit and Vegetables: Applications and Factors Modulating Its Efficacy on Bioactive Compounds and Microbial Growth

Magalí Darré, Ariel Roberto Vicente, Luis Cisneros-Zevallos et al.

Ultraviolet (UV) radiation has been considered a deleterious agent that living organisms must avoid. However, many of the acclimation changes elicited by UV induce a wide range of positive effects in plant physiology through the elicitation of secondary antioxidant metabolites and natural defenses. Therefore, this fact has changed the original UV conception as a germicide and potentially damaging agent, leading to the concept that it is worthy of application in harvested commodities to take advantage of its beneficial responses. Four decades have already passed since postharvest UV radiation applications began to be studied. During this time, UV treatments have been successfully evaluated for different purposes, including the selection of raw materials, the control of postharvest diseases and human pathogens, the elicitation of nutraceutical compounds, the modulation of ripening and senescence, and the induction of cross-stress tolerance. Besides the microbicide use of UV radiation, the effect that has received most attention is the elicitation of bioactive compounds as a defense mechanism. UV treatments have been shown to induce the accumulation of phytochemicals, including ascorbic acid, carotenoids, glucosinolates, and, more frequently, phenolic compounds. The nature and extent of this elicitation have been reported to depend on several factors, including the product type, maturity, cultivar, UV spectral region, dose, intensity, and radiation exposure pattern. Even though in recent years we have greatly increased our understanding of UV technology, some major issues still need to be addressed. These include defining the operational conditions to maximize UV radiation efficacy, reducing treatment times, and ensuring even radiation exposure, especially under realistic processing conditions. This will make UV treatments move beyond their status as an emerging technology and boost their adoption by industry.

Chemical technology
DOAJ Open Access 2021
Antibacterial Potential of Biosynthesized Zinc Oxide Nanoparticles against Poultry-Associated Foodborne Pathogens: An In Vitro Study

Hidayat Mohd Yusof, Nor’Aini Abdul Rahman, Rosfarizan Mohamad et al.

Since the emergence of multidrug-resistant bacteria in the poultry industry is currently a serious threat, there is an urgent need to develop a more efficient and alternative antibacterial substance. Zinc oxide nanoparticles (ZnO NPs) have exhibited antibacterial efficacy against a wide range of microorganisms. Although the in vitro antibacterial activity of ZnO NPs has been studied, little is known about the antibacterial mechanisms of ZnO NPs against poultry-associated foodborne pathogens. In the present study, ZnO NPs were successfully synthesized using <i>Lactobacillus plantarum</i> TA4, characterized, and their antibacterial potential against common avian pathogens (<i>Salmonella</i> spp., <i>Escherichia coli</i>, and <i>Staphylococcus aureus</i>) was investigated. Confirmation of ZnO NPs by UV-Visual spectroscopy showed an absorption band center at 360 nm. Morphologically, the synthesized ZnO NPs were oval with an average particle size of 29.7 nm. Based on the dissolution study of Zn<sup>2+</sup>, ZnO NPs released more ions than their bulk counterparts. Results from the agar well diffusion assay indicated that ZnO NPs effectively inhibited the growth of the three poultry-associated foodborne pathogens. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were assessed using various concentrations of ZnO NPs, which resulted in excellent antibacterial activity as compared to their bulkier counterparts. <i>S. aureus</i> was more susceptible to ZnO NPs compared to the other tested bacteria. Furthermore, the ZnO NPs demonstrated substantial biofilm inhibition and eradication. The formation of reactive oxygen species (ROS) and cellular material leakage was quantified to determine the underlying antibacterial mechanisms, whereas a scanning electron microscope (SEM) was used to examine the morphological changes of tested bacteria treated with ZnO NPs. The findings suggested that ROS-induced oxidative stress caused membrane damage and bacterial cell death. Overall, the results demonstrated that ZnO NPs could be developed as an alternative antibiotic in poultry production and revealed new possibilities in combating pathogenic microorganisms.

Veterinary medicine, Zoology
DOAJ Open Access 2021
Seasonal Variation of Antioxidant Capacity, Phenols, Minerals and Essential Oil Components of Sage, Spearmint and Sideritis Plants Grown at Different Altitudes

Antonios Chrysargyris, Efstathios Evangelides, Nikolaos Tzortzakis

Medicinal and aromatic plants are well appreciated for their antioxidant and biocidal activities, while great variation on these activities can be related to the species, environmental conditions and harvesting period. In the present study, the seasonal variation of the antioxidant activity, mineral content, yield and chemical composition of the essential oils (EOs) of sage (<i>Salvia officinalis</i> L.), sideritis (<i>Sideritis perfoliata</i> L. subsp. <i>perfoliata</i>) and spearmint (<i>Mentha spicata</i> L.) were tested under two different environmental conditions, each with a different altitude (namely mountainous and plain). Season affected total phenolic content and antioxidant capacity with increased values during winter and lower values during summer period. In summer, plants accumulated more Fe and had higher EO yield, while P and Na were accumulated more in winter. Altitude had a lesser effect on antioxidant capacity of the plants; however, increased minerals (N, K, Na and Ca) accumulation was found in plain areas. Sage plants had the highest antioxidant capacity, Zn content and EO yield. Sideritis had increased Fe content and spearmint plants revealed high N, Na and Mg levels. Furthermore, altitude and season had an impact on the content of main EOs components in all species. FRAP and ABTS were variably correlated with total phenols and minerals, depending on the species, season and altitude. In few cases, antioxidant activity was found to be inversely linked to some EO components (e.g., α-thujone in sage). Finally, the antioxidant content, minerals and EO yield and composition of the examined MAPs were all altered by season and altitude. These findings can be utilized to implement sage, sideritis and spearmint farming in specific ecosystems, determining the season and areas for harvesting the plants, in order to produce high-value products.

DOAJ Open Access 2020
Micropropagation of some grape varieties in Kazakhstan

Kazybayeva Saule, Kovalchuk Irina, Turdiyev Timur et al.

The article shows the improvement of the process of initiation into in vitro the culture and the clonal micropropagation of grape varieties. The optimal culture media for the initiation and cloning of grapes in vitro have been selected. During initiation on Murashige and Skoog, agar medium with ½ or ¾ concentration of macroand micronutrients and hormones (0.5 mg/l BAP and 0.1 mg/l IBA) is optimal. For micropropagation is suitable MS medium modified by some elements of mineral nutrition: 825 mg/l NH4NO3, 166 mg/l CaCl2, 15 mg/l ferrum chelate; best hormonal composition depends on variety: a) 0.5-1 mg/l BAP and 0.1-0.5 mg/l IBA; b) 0.5 mg/l 2-iP and 0.5 mg/l GA3.

Microbiology, Physiology
DOAJ Open Access 2020
Cellular Response to Vitamin C-Enriched Chitosan/Agarose Film with Potential Application as Artificial Skin Substitute for Chronic Wound Treatment

Vladyslav Vivcharenko, Michal Wojcik, Agata Przekora

The treatment of chronic wounds is still a meaningful challenge to physicians. The aim of this work was to produce vitamin C-enriched chitosan/agarose (CHN/A) film that could serve as potential artificial skin substitute for chronic wound treatment. The biomaterial was fabricated by a newly developed and simplified method via mixing acidic chitosan solution with alkaline agarose solution that allowed to obtain slightly acidic pH (5.97) of the resultant material, which is known to support skin regeneration. Vitamin C was immobilized within the matrix of the film by entrapment method during production process. Produced films (CHN/A and CHN/A + vit C) were subjected to comprehensive evaluation of cellular response with the use of human skin fibroblasts, epidermal keratinocytes, and macrophages. It was demonstrated that novel biomaterials support adhesion and growth of human skin fibroblasts and keratinocytes, have ability to slightly reduce transforming growth factor-beta 1 (TGF-β1) (known to be present at augmented levels in the epidermis of chronic wounds), and increase platelet-derived growth factor-BB (PDGF-BB) secretion by the cells. Nevertheless, addition of vitamin C to the biomaterial formulation does not significantly improve its biological properties due to burst vitamin release profile. Obtained results clearly demonstrated that produced CHN/A film has great potential to be used as cellular dermal, epidermal, or dermo-epidermal graft pre-seeded with human skin cells for chronic wound treatment.

DOAJ Open Access 2020
Screening of powdery mildew resistant barley accessions from Ethiopia for tolerance to abiotic stressors

R. A. Abdullaev, O. V. Yakovleva, I. A. Kosareva et al.

Background. Analyzing the adaptive potential of cultivated barley with the aim of using new genotypes selected and developed in the process of work is a priority trend in scientific research. The Ethiopian barleys adapted to a variety of soil and climate conditions are characterized by many valuable biological and agronomic traits. Of particular value are genotypes that combine resistance to harmful organisms and environmental stressors.Materials and methods. The collection accessions of Ethiopian barley possessing powdery mildew resistance were studied for tolerance to adverse edaphic factors (chloride salinity and high content of toxic aluminum ions in the soil). Resistance to abiotic stressors was assessed in laboratory experiments. In the study of salt tolerance, a ‘roll-based’ assessment technique was used, which takes into account the inhibition of root growth under salt (NaCl) stress conditions, compared with the reference conditions without salinization. Aluminum sensitivity of barley accessions was diagnosed in the early stages of plant development using the root test.Results and conclusions. A polymorphism of Ethiopian barleys for resistance to adverse edaphic factors was revealed. Twentyone new sources of barley resistance to toxic aluminum ions were identified, of which accessions k-8552 and k-22933 were classified as highly resistant. Accessions k-17554, k-19975, k-20029, k-20048, k-22752, k-23450 and k-25009 proved resistant to soil salinization. Barley accessions k-17554, k-22752 and k-25009 were characterized by complex resistance to powdery mildew, toxic aluminum ions, and chloride soil salinity.

Biotechnology, Botany
DOAJ Open Access 2019
Optimization of 4-1BB antibody for cancer immunotherapy by balancing agonistic strength with FcγR affinity

Xinyue Qi, Fanlin Li, Yi Wu et al.

Agonistic 4-1BB antibodies developed for cancer immunotherapy have suffered from either hepatotoxicity or insufficient anti-cancer activity. Here the authors determine the contribution of FcγR binding and agonistic strength to these outcomes, and engineer a 4-1BB antibody with potent anti-tumor effect and no liver toxicity in mice.

DOAJ Open Access 2019
Transcriptome Profiling and Genome-Wide Association Studies Reveal GSTs and Other Defense Genes Involved in Multiple Signaling Pathways Induced by Herbicide Safener in Grain Sorghum

You Soon Baek, Loren V. Goodrich, Loren V. Goodrich et al.

Herbicide safeners protect cereal crops from herbicide injury by inducing genes and proteins involved in detoxification reactions, such as glutathione S-transferases (GSTs) and cytochrome P450s (P450s). Only a few studies have characterized gene or protein expression profiles for investigating plant responses to safener treatment in cereal crops, and most transcriptome analyses in response to safener treatments have been conducted in dicot model species that are not protected by safener from herbicide injury. In this study, three different approaches were utilized in grain sorghum (Sorghum bicolor (L.) Moench) to investigate mechanisms involved in safener-regulated signaling pathways. An initial transcriptome analysis was performed to examine global gene expression in etiolated shoot tissues of hybrid grain sorghum following treatment with the sorghum safener, fluxofenim. Most upregulated transcripts encoded detoxification enzymes, including P450s, GSTs, and UDP-dependent glucosyltransferases (UGTs). Interestingly, several of these upregulated transcripts are similar to genes involved with the biosynthesis and recycling/catabolism of dhurrin, an important chemical defense compound, in these seedling tissues. Secondly, 761 diverse sorghum inbred lines were evaluated in a genome-wide association study (GWAS) to determine key molecular-genetic factors governing safener-mediated signaling mechanisms and/or herbicide detoxification. GWAS revealed a significant single nucleotide polymorphism (SNP) associated with safener-induced response on chromosome 9, located within a phi-class SbGST gene and about 15-kb from a different phi-class SbGST. Lastly, the expression of these two candidate SbGSTs was quantified in etiolated shoot tissues of sorghum inbred BTx623 in response to fluxofenim treatment. SbGSTF1 and SbGSTF2 transcripts increased within 12-hr after fluxofenim treatment but the level of safener-induced expression differed between the two genes. In addition to identifying specific GSTs potentially involved in the safener-mediated detoxification pathway, this research elucidates a new direction for studying both constitutive and inducible mechanisms for chemical defense in cereal crop seedlings.

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