Separation Method Research Articles

Neem (Azadirachta indica) seed extract formulation for managing anthracnose and gray mold diseases in strawberry

Anthracnose caused by Colletotrichum nymphaeae and gray mold caused by Botrytis cinerea are the most epidemic fungal diseases causing significantly losses in strawberry plantings. The objective of the study is to determine the antifungal activity of neem (Azadirachta indica A. Juss.) seed extracts and preparing new formulated antifungal agent. Plant extracts including alcoholic, aqueous and oil were extracted from neem seeds and used in concentrations of 1000, 2000, 4000, 8000 and 10,000 µl/l to control the vegetative mycelial growth of pathogens. The results showed that alcoholic extract had highest antifungal effect and used for the formulation. The concentration of 10,000 microliters of alcoholic extract showed 91.6 % inhibition of gray mold disease, while it inhibited 80.66 % in anthracnose disease and a significant difference was observed between them. For encapsulation of alcoholic neem extract with plant biopolymers with new changes, the separation method of water-miscible solvent through precipitation with salt was used. The results showed that the best effect of the formulation was observed at a dose of four per thousand. Inhibition at this concentration as the best option in terms of controlling gray mold and anthracnose disease was 86.3 % and 79.38 %, respectively, and they were placed in the same statistical group (d). This formulation is designed to determine the minimum concentration threshold and reduce the consumption of alcoholic extract. Based on the results, the use of formulated alcoholic extract of neem seed as an alternative to chemical fungicides can help control anthracnose and gray mold in strawberries.

Ship-Radiated Noise Separation in Underwater Acoustic Environments Using a Deep Time-Domain Network

Ship-radiated noise separation is critical in both military and economic domains. However, due to the complex underwater environments with multiple noise sources and reverberation, separating ship-radiated noise poses a significant challenge. Traditionally, underwater acoustic signal separation has employed blind source separation methods based on independent component analysis. Recently, the separation of underwater acoustic signals has been approached as a deep learning problem. This involves learning the features of ship-radiated noise from training data. This paper introduces a deep time-domain network for ship-radiated noise separation by leveraging the power of parallel dilated convolution and group convolution. The separation layer employs parallel dilated convolution operations with varying expansion factors to better extract low-frequency features from the signal envelope while preserving detailed information. Additionally, we use group convolution to reduce the expansion of network size caused by parallel convolution operations, enabling the network to maintain a smaller size and computational complexity while achieving good separation performance. The proposed approach is demonstrated to be superior to the other common networks in the DeepShip dataset through comprehensive comparisons.

Improvements of EEG Signal Quality: A Hybrid Method of Blind Source Separation and Variational Mode Destruction to Reduce Artifacts

The electroencephalogram (EEG) is a crucial tool for studying brain activity; yet it frequently encounters artifacts that distort meaningful neural signals. This paper addresses the challenge of artifact removal through a unique hybrid method, combining Variational Mode Decomposition (VMD) techniques with Blind Source Separation (BSS) algorithms. VMD, recognized for its adaptability to non-linear and non-stationary EEG data, as well as its ability to alleviate mode mixing and the “endpoint effect,” which serves as an effective preprocessing step. The paper evaluates the performance of two integrated BSS algorithms, AMICA and AMUSE, across various criteria. Comparisons across metrics such as Euclidean distance, Spearman correlation coefficient, and Root Mean Square Error reveal similar performance between AMICA and AMUSE. However, a distinct divergence is evident in the Signal to Artifact Ratio (SAR). When employed with VMD, AMICA demonstrates superiority in effectively discerning and segregating brain signals from artifacts, which gives a mean value of 1.0924. This study introduces a potent hybrid VMDBSS approach for enhancing EEG signal quality. The findings emphasize the notable impact of AMICA, particularly in achieving optimal results in artifact removal, as indicated by its superior performance in SAR. The abstract concludes by underlining the significance of these results, emphasizing AMICA’s pivotal role in achieving the highest measurable evaluation value, making it a compelling choice for researchers and practitioners in EEG signal processing.

ДЕКОМПОЗИЦИЯ СПЕКТРА ПОГЛОЩЕНИЯ АЦЕТОНОВОГО ЭКСТРАКТА МИКРОВОДОРОСЛИ ARTHROSPIRA (SPIRULINA) PLATENSIS NORTH. GEITL.

We have described the absorption spectra of acetone extract of the microalga Arthrospira (Spirulina) platensis by mathematical models of carotenoids and chlorophylls in the range from 400 to 700 nm. The obtained values of pigment concentrations agree well with standard methods. A model of the absorption spectrum of acetone extract of A. platensis can be used to determine the concentration of chlorophyll a and carotenoids. The absence of chlorophyll b contribution to the total absorption spectrum was shown. The method of mathematical separation of acetone extract absorption spectrum in Microsoft Excel program was implemented. Calculations performing approximations of pigment concentrations by minimizing the sum of squares of deviations between the true absorption spectrum and its mathematical model have been performed using the spreadsheet processor with the help of the solution search tool.

Immunity-Empowered Collaboration Security Protection for Mega Smart Cities

The cyberphysical systems of smart cities are facing increasingly severe attack situations, and traditional separate protection methods are difficult to effectively respond to. It is urgent to coordinate public safety and cybersecurity protection. However, the integration of the two faces many challenges and is a very promising research field. The aim of this study is to investigate technical approaches for the synergy between public safety and cybersecurity. This paper proposes a smart city safety protection model inspired by the human immune mechanism. It was found that through a three-line defense architecture similar to the human immune mechanism, and with the help of certain algorithms and functional middleware modules, public safety and cybersecurity protection components can be dynamically combined to achieve collaboration. This work has verified through experiments a valuable path to effectively resist complicated attack threats intertwined with public safety and cybersecurity factors.

Analysis of aggregation profile of glucagon using SEC-HPLC and FFF-MALS methods.

Recently, the first generic glucagon for injection was approved for the treatment of severe hypoglycemia. Unlike its brand name recombinant glucagon, the generic glucagon is synthetic. Since glucagon has a high propensity to form aggregates in solution, it is essential to assess the aggregation profile of the synthetic glucagon compared to the recombinant glucagon. In this study, two robust separation methods, size-exclusion chromatography (SEC-HPLC) and field-flow fractionation coupled with a multi-angle light scattering detector (FFF-MALS), were employed to characterize generic and brand glucagon aggregation in six lots (three newly released, three expired). The presence of aggregation in samples was determined from the generated chromatograms and analyzed. The study showed that both products have comparable aggregation profiles. The SEC-HPLC demonstrated that in both glucagon versions, the expired lots had a higher percentage of dimers than the newly released lots, but even at expiration, the amount was negligible (∼0.1%). The FFF-MALS method did not detect any dimers or higher molecular weight aggregates. Further evaluation of the detection limit found that FFF-MALS was unable to detect aggregates at amounts lower than 0.5% of total glucagon. The negligible amounts of dimer detected in the generic and brand glucagon indicate that both versions are physically stable and are not prone to aggregation under clinically relevant conditions.

Efficient Metal Extraction from Dilute Solutions: A Review of Novel Selective Separation Methods and Their Applications

Notable increases in metal consumption and declining ore grades in recent decades have stressed the significance of dilute solutions as secondary sources of valuable metals. Moreover, environmental considerations and the imperative of sustainable development have further emphasized their treatment. Therefore, finding an efficient solution for separating metals from dilute solutions has attracted the attention of numerous researchers. This paper reviews the purification processes of dilute solutions and highlights key achievements of published research works. Although this study focuses on evaluating the efficiency of recently developed aqueous-phase purification methods, such as immobilized ligands, ionic liquids, and air-assisted solvent extraction, the application of conventional processes to treat these solutions, such as solvent extraction, ion exchange, membranes, chemical precipitation, and adsorption are also briefly outlined. To provide a comprehensive assessment, more than 200 research articles were reviewed, and their key findings are stated in this study. This research contributes to the advancement of knowledge of metal recovery from dilute solutions and sheds light on the dynamic evolution of this field.

Consolidation and seepage solutions in enclosure space based on non-zero-constant values boundary.

Research is ongoing to find solutions to the problem of Consolidation and seepage in saturated clay in enclosure space. Firstly, the boundary of non-zero-constant values is established, considering the seepage boundary of the clay is affected by pumping water or lowering boundary pressure on the site. Secondly, the differential equation is established to reflect the spatial and temporal variations of excess pore water pressure dissipation in the clay in enclosure space, and the solution is derived using variable separation methods. Finally, based on results of the solution derived, contour maps of the water pressure are drawn corresponding with the different inhomogeneous boundary conditions.

First report of anthracnose of Lithocarpus polystachyus caused by Colletotrichum fructicola in China.

Lithocarpus polystachyus (Wall. ex A. DC.), an economically valuable plant species belonging to the Fagaceae family, has been used as herbal tea to prevent diabetes because of the high content of flavonoids and dihydrochalcones in the leaves (Shang et al. 2022). In July 2022, the severe leaf lesion on L. polystachyus was first observed in Yongshun County, Xiangxi autonomous prefecture (28°45'34''N, 109°40'11''E), Hunan province, China. Yongshun County is characterized by hills and mountains, situated in a subtropical region with a mild and humid climate. A second outbreak in July 2023 was observed in the same area. The observed incident rates in the past two years were 87.3% and 90.6%, respectively. Once infected, almost all plant leaves will be infected, leading to a substantial reduction in the yield of L. polystachyus. The disease presented symptoms characterized by round or irregularly shaped lesions that initially manifested as brown spots. These lesions frequently merged into larger, dark-brown areas along the leaf margins before eventually wilting. To ascertain the pathogenic species responsible for this disease, fungal isolation was conducted using a tissue separation method (Xu et al. 2023). The infected leaf tissues were surface-disinfected with 75% ethanol and 0.1% HgCl then small pieces (1×1 cm), were placed onto potato dextrose agar (PDA) medium (Sigma-Aldrich, 70139) and incubated at 28°C for 6-9 days. Colonies were villiform and initially white, becoming gray after 6 days. Sterilized dissecting needles were used to pick single hyphal tips from the edge of the colonies and placed onto PDA for strain purification. After 15 days, the purified colonies grew fluffy white hyphae with abundant conidia. The conidia were cylindrical, had round ends, and ranged from 5.75 to 14.83 μm long and 1.75 to 2.38 μm wide (n=50). According to morphological and cultural characteristics, these isolates were preliminarily identified as Colletotrichum fructicola Prihast., L. Cai & K.D. Hyde (Damm et al. 2012). To further affirm the identity of the pathogen, DNA was extracted from mycelia using a DNA extraction kit (Sigma-Aldrich, G2N70). The internal transcribed spacer (ITS) region, the transcription elongation factor (TEF), and the actin (ACT) gene were then amplified from genomic DNA extracted from three isolates (Cof1, Cof2, and Cof3) using specific primers. The primers utilized were ITS1/ITS4 (White et al. 1990), EF1-728F/EF1-986R and ACT-512F/ACT-783R (Carbone and Kohn 1999) for ITS region, transcription elongation factor gene and actin gene amplification, respectively. Sequence identity indicated that these isolates were highly homologous to C. fructicola. The ITS (Genbank No. PP002156, OR880553 and OR880554), TEF (No. PP061421, PP061422 and PP061423), and ACT (No. PP061418, PP061419 and PP061420) sequences of the isolates Cof1, Cof2, and Cof3 shared 99 to 100% identity with their counterparts (No. OR083309, MF627961, and OQ427895) in C. fructicola, respectively. A neighbor-joining phylogenetic tree constructed using MEGA11 (Tamura et al. 2021) also indicated that these isolates were C. fructicola. Both morphological and molecular characteristics confirmed the identification of this pathogen as C. fructicola. Colletotrichum species are known to cause anthracnose disease in a variety of economically important crops (Sharma and Kulshrestha 2015). To further validate the ability of the isolated C. fructicola to induce the same symptoms as observed in the field, the pathogenicity assay was assessed following Koch's postulates (Gradmann, 2014). Conidial suspensions (1×105 conidia per mL) from three isolates were individually inoculated onto artificially wounded leaves of 3-year-old L. polystachyus. Negative controls were established by inoculating leaf wounds with sterile distilled water. The plants were incubated in a greenhouse at 28°C and 90% humidity with a 12-h photoperiod. The experiment was replicated three times. Necrotic lesions were observed on all pathogen-inoculated wounds within 6 days after inoculation, whereas controls showed no observable symptoms. Morphological and molecular characterization of re-isolated pathogens from infected leaves indicated that the pathogens were identical. To our knowledge, this is the first report of anthracnose of L. polystachyus caused by C. fructicola in China. Farmers in the local mountainous areas are economically reliant on L. polystachyus production, while anthracnose has caused over half of the trees to lose their commercial value, resulting in significant economic losses. Our findings hold great promise for advancing strategies in the prevention and treatment of anthracnose in L. polystachyus.

Experimental research on combined magnetic separation and flotation for coal gasification fine slag

ABSTRACT To address the challenging issue of achieving high-precision carbon-ash separation in coal gasification fine slag, magnetic separation and flotation techniques were employed to study their respective separation effect. Optimization tests were conducted to determine the optimal magnetic field gradient and magnetic field intensity, and the ash content of magnetic separation concentrates was 72.18%, with a reduction of 7.28% compared to the sample. Additionally, the magnetic separation tailings exhibited an ash content of 93.99%. Through flotation tests, the optimum conditions for kerosene and composite collector was established. The ash content of flotation concentrates decreased by 16.39% compared to the sample, and the ash content of flotation tailings was 95.83%. A comparative analysis revealed that the combined separation process outperforms single separation methods in reducing the ash content of the concentrates, and realize the further quality improvement and separation effect. Detailed analysis of magnetic characteristics and XRD, XPS analysis studies on the sample and the products, indicated that the magnetic separation effectively pre-removes a certain amount of magnetic high ash minerals. Furthermore, the collector treatment significantly increased hydrophobicity difference between residual carbon and ash matter, which ultimately enhancing the flotation effect.

Methods of preventing surgical site infections

Healthcare-associated infections are the most common and relevant to all healthcare facilities of all types. Surgical site infections are the most frequently reported type of healthcare-associated infections. Surgical site infections are also one of the main causes of prolonged hospital stays, prolonged antibiotic therapy, unplanned re-hospitalizations, worsened long-term patient outcomes and the prescription of additional surgical interventions. At present, it is prevention that has been identified as the single most important strategy to combat surgical site infection. The proposed three-stage model combines perioperative interventions as well as interdisciplinary collaboration to continuously improve the quality of care. This approach includes preoperative, intraoperative, and postoperative prevention methods. Current preoperative strategies for the prevention of surgical site infections can significantly reduce the risk of developing this nosology; one important aspect of preoperative prophylaxis includes the identification, elimination, and/or correction of modifiable as well as non-modifiable risk factors. In addition, it is possible to identify intraoperative risk factors, of which the duration of surgical intervention is fundamentally important. Postoperative risk factors include hyperglycemia and diabetes mellitus, postoperative wound care and blood transfusion. Many effective ways of preventing surgical site infections have been developed, which include separate methods of preoperative, intraoperative and postoperative prophylaxis, however, only through the implementation of a comprehensive model that combines all perioperative measures, health care institutions will be able to effectively reduce the incidence of healthcare-associated infections and improve patient outcomes. Despite the fact that currently there is an active development of new methods of surgical site infections prophylaxis, the direct implementation of these technologies in the practical activity of specialists is of primary importance.

Numerical Calculation of Gas–Liquid Two-Phase Flow in Tesla Valve

In this paper, the gas–liquid two-phase flow within a Tesla valve under zero-gravity conditions is numerically studied. Based on the VOF model and the inlet two-phase separation method, the forward and reverse flow patterns and pressure drop changes in a Tesla valve at different inlet velocities were analyzed. At an inlet velocity of 0.1–0.2 m/s, the flow pattern was slug flow, the bubbles were evenly distributed in different positions in the Tesla valve, and the velocity difference between the main pipe and the arc branch pipe was small. When the inlet velocity was 0.4 m/s, the main flow pattern was annular flow, and there was a phenomenon of gas–liquid phase separation through different flow channels, which was related to centrifugal force. At an inlet velocity of 0.6–0.8 m/s, bubbly flow and slug flow coexisted, which was related to the uneven velocity. In the study range, the difference in the forward and reverse pressure drops of two-phase flow was smaller than that of single-phase flow, and the two-phase diodicity decreased first and then increased with the change in inlet velocity, reaching minimum values of 0.78 at 0.2 m/s and 1.44 at 0.8 m/s.

Tensor Low-Rank and Sparse Decomposition and Its Application in Bearing Fault Information Separation

Abstract Properly separating fault information from noisy measured signals is crucial for effective bearing health sensing. However, conventional fault information separation methods face challenges such as predefined model parameters and poor noise robustness. Additionally, with the advent of Industry Big Data, multichannel monitoring signals present significant challenges for traditional single decomposition approaches. To address these challenges and fully extract potential fault information, this paper introduces a tensor low-rank and sparse decomposition (tensor LRSD) approach for multichannel signal processing. Inspired by matrix LRSD, we construct a tensor LRSD model that adaptively decomposes the signal into a tensor sparse term containing fault information and a low-rank term representing the intrinsic signal pattern. To further enhance the decomposition performance, a maximum correlation-based selection strategy is designed. This strategy evaluates the correlation between each tensor slice and selects appropriate tensor sparse terms for fault information extraction. Simulation analysis and two experimental studies involving typical bearing failures are implemented to verify the capability and superiority of the presented tensor LRSD approach. The consequences demonstrate that the presented method outperforms conventional techniques, showcasing its capability to effectively separate fault information from noisy signals.

Micro- and Nano-Pollutants from Tires and Car Brakes Generated in the Winter Season in the Poznan City Urban Environment

This research, focusing on the environmental impact of tire and brake disc pad wear, constitutes a significant area of transport-related studies. These two key vehicle components are not only the most frequently worn but also generate micro- and nano-pollutants (i.e., rubber, metal oxides) that potentially harm the environment. Over half of the globally produced natural and synthetic rubbers, which amounted to about 30 million tons in 2022, are used for tire production. This work focuses on the study of roadside snow, sand, and standing water deposits from various locations in the urban agglomeration (Poznań, Poland) during the winter season, determining their qualitative composition and the quantitative content of pollutants originating from tire abrasion. In addition, the method of washing nano- and micro-rubber particles and their full characteristics was also presented. Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic studies, optical and scanning electron microscopy (SEM-EDS), particle size studies using a dynamic light scattering (DLS) particle analyzer, and thermogravimetric analysis (TGA) were conducted for a detailed characterization of the pollutants in the environment. The conducted particle separation methods allowed for the extraction of a fraction mainly containing gum residues with particle sizes less than 2 µm. The results of these tests make it possible to estimate the level of contamination with rubber and metal residues during the abrasion of tires, pads, and brake discs while driving, which is crucial for understanding the impact of vehicle part exploitation on the environment.

An Adsorptive Membrane Platform for Precision Ion Separation: Membrane Design and First‐Principles Studies

One of the key challenges in separation science is the lack ofprecise ion separation methods and mechanistic understanding crucial for efficiently recovering critical materials from complex aqueous matrices. Herein, first‐principles electronic structure calculations and in‐situ Raman spectroscopy are studied to elucidate the factors governing ion discrimination in an adsorptive membrane specifically designed for transition metal ion separation. Density functional theory calculations and in‐situ Raman data jointly reveal the thermodynamically favorable binding preferences and detailed adsorption mechanisms for competing ions. How membrane binding preferences correlate with the electronic properties of ligands is explored, such as orbital hybridization and electron localization. The findings underscore the importance of the phenolate group in oxime ligands for achieving high selectivity among competing transition metal ions. In‐depth understanding on which specific atomistic site within the microenvironment of metal‐ligand binding pockets governs the ion discrimination behaviors of the host will build a solid foundation to guide the rational design of next‐generation materials for precision separation essential for energy technologies and environment remediation. In tandem, synthetic controllability is demonstrated to transform 3D micrometer‐scale crystals to a 2D crystalline selective layer in membranes, paving the way for more precise and sustainable advances in separation science.

The role of the Golden2-like (GLK) transcription factor in regulating terpenoid indole alkaloid biosynthesis in Catharanthus roseus

Key messageA GLK homologue was identified and functionally characterized in Catharanthus roseus. Silencing CrGLK with VIGS or the chloroplast retrograde signaling inducer lincomycin increased terpenoid indole alkaloid biosynthesis.Catharanthus roseus is the sole source of the chemotherapeutic terpenoid indole alkaloids (TIAs) vinblastine and vincristine. TIA pathway genes, particularly genes in the vindoline pathway, are expressed at higher levels in immature versus mature leaves, but the molecular mechanisms responsible for this developmental regulation are unknown. We investigated the role of GOLDEN2-LIKE (GLK) transcription factors in contributing to this ontogenetic regulation since GLKs are active in seedlings upon light exposure and in the leaf’s early development, but their activity is repressed as leaves age and senesce.We identified a GLK homologue in C. roseus and functionally characterized its role in regulating TIA biosynthesis, with a focus on the vindoline pathway, by transiently reducing its expression through two separate methods: virus-induced gene silencing (VIGS) and application of chloroplast retrograde signaling inducers, norflurazon and lincomycin. Reducing CrGLK levels with each method reduced chlorophyll accumulation and the expression of the light harvesting complex subunit (LHCB2.2), confirming its functional homology with GLKs in other plant species. In contrast, reducing CrGLK via VIGS or lincomycin increased TIA accumulation and TIA pathway gene expression, suggesting that CrGLK may repress TIA biosynthesis. However, norflurazon had no effect on TIA gene expression, indicating that reducing CrGLK alone is not sufficient to induce TIA biosynthesis. Future work is needed to clarify the specific molecular mechanisms leading to increased TIA biosynthesis with CrGLK silencing. This is the first identification and characterization of GLK in C. roseus and the first investigation of how chloroplast retrograde signaling might regulate TIA biosynthesis.

A Validated Chiral Chromatography Method for Enantiomeric Separation of Pomalidomide in Human Plasma.

In the present work, new chiral stationary phase high-performance liquid chromatography (CSP-HPLC) method was established and validated for the quantification of pomalidomide (PMD) enantiomers in human plasma. The chromatographic enantiomeric separation was achieved on a Daicel-CSP, Chiralpack IA 4.6 × 250mm, 5μm; because of its advantages of high degree of retention, high resolution capacity, better reproducibility, ability to produce lower back pressure and low degree of tailing. The mobile phase was maintained as methanol: glacial acetic acid (499.50ml:50μL). Ultraviolet wavelength for detection was 220nm. PMD enantiomer-I and enantiomer-II were separated at 8.83 and 15.34min, respectively. Limit of detection and limit of quantification for each enantiomer and the calibration curve of standard PMD was linear in range between 10-5,000ngmL-1. The method was validated according to The International Council for Harmonisation of Technical Requirements of Pharmaceuticals for Human Use (ICH(Q2R1)) specific guidelines. We found no interference peak with PMD chromatogram obtained. This is a simple, reliable and specific method for detection and quantification of enantiomer of PMD in human plasma sample.

Investigating the impact of the sulfonation degree in sulfonated polyphenylsulfone (sPPSU) on PES/sPPSU polymer blend membranes

Polyethersulfone (PES) has widespread applications due to its excellent processability, mechanical strength, and chemical resistance. Nevertheless, its hydrophobic nature often leads to severe fouling and permeance decline. To improve the hydrophilicity of PES membranes, polymer blending is one of the most common methods. In this work, a series of sulfonated polyphenylene sulfones (sPPSU) with 1.9, 4.5, 8.2, 12.7, 19 degrees of sulfonation (DS) were synthesized and used to blend with PES. The PES/sPPSU blends were found to be compatible by calculating their theoretical enthalpy of mixing and measuring their glass transition temperatures (Tg's) at a blend weight ratio of 1:1. Ultrafiltration (UF) membranes were cast using the nonsolvent-induced phase separation (NIPS) method. It was found that 50/50 PES/sPPSU blend membranes with a DS equaling to or exceeding 8.2 eliminated finger-like macrovoids, resulting in a thinner and tight cross-sectional structure. A higher DS of sPPSU rendered the blend membranes with more hydrophilicity and oleophobicity as well as a more negatively charged surface. The unmodified PES membrane had rejections of 87.47 % and 91.5 % in ultrafiltration tests using feed solutions containing BSA and oil/water emulsion, respectively. The rejections could be further increased to 99.37 % and 97.17 % respectively by the blend membranes. The blend membranes consisting of a higher DS of sPPSU also exhibited a higher permeance, lower BSA absorption and better anti-fouling properties than the PES membrane.

Signature of f(R) gravity via Lemaître–Tolman–Bondi inhomogeneous perturbations

We analyze inhomogeneous cosmological models in the local Universe, described by the Lemaître–Tolman–Bondi (LTB) metric and developed using linear perturbation theory on a homogeneous and isotropic Universe background. Focusing on the different evolution of spherical symmetric inhomogeneities, we compare the Λ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Lambda $$\\end{document}LTB model, in which the cosmological constant Λ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Lambda $$\\end{document} is included in the LTB formalism, with inhomogeneous cosmological models based on fR\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f\\left( R\\right) $$\\end{document} modified gravity theories viewed in the Jordan frame. We solve the system of field equations for both inhomogeneous cosmological models adopting the method of separation of variables: we integrate analytically the radial profiles of local perturbations, while their time evolution requires a numerical approach. The main result of the analysis concerns the different radial profiles of local inhomogeneities due to the presence of a non-minimally coupled scalar field in the Jordan frame of fR\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f\\left( R\\right) $$\\end{document} gravity. While radial perturbations follow a power-law in the Λ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Lambda $$\\end{document}LTB model, Yukawa-like contributions appear in the fR\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f\\left( R\\right) $$\\end{document} theory. Interestingly, this latter peculiar behavior of radial profile is not affected by the choice of the fR\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f\\left( R\\right) $$\\end{document} functional form. The numerical solution of time-dependent perturbations exhibits a non-diverging profile. This work suggests that investigations about local inhomogeneities in the late Universe may allow us to discriminate if the present cosmic acceleration is caused by a cosmological constant term or a modified gravity effect.

Screening of Endophytic Antagonistic Bacteria in Wheat and Evaluation of Biocontrol Potential against Wheat Stripe Rust.

Wheat stripe rust is globally one of the most important diseases affecting wheat. There is an urgent need to develop environmentally safe and durable biological control options to supplement the control that is achieved with breeding and fungicides. In this study, endophytic bacteria were isolated from healthy wheat through the tissue separation method. Antagonistic endophytic bacteria were screened based on the control effect of urediniospore germination and wheat stripe rust (WSR). The taxonomic status of antagonistic strains was determined based on morphological, physiological, and biochemical characteristics and molecular biological identification (16S rDNA and gyrB gene sequence analysis). Finally, the potential growth-promoting effect of different concentrations of antagonists on wheat seedlings and the biological control effect of WSR were studied. A total of 136 strains of endophytic bacteria belonging to 38 genera were isolated. Pseudomonas was the most common bacterial genus, with 29 isolates (21%). The biological control effect of different isolates was assessed using an urediniospore germination assay. The isolate XD29-G1 of Paenibacillus polymyxa had the best performance, with 85% inhibition of spore germination during primary screening. In the deep screening, the control effect of XD29-G1 on wheat stripe rust was 60%. The antagonist XD29-G1 promoted the germination of wheat seeds and the growth of wheat seedlings at a solution dilution of 10-7 cfu/mL. The pot experiment results showed that different dilution concentrations of the strain had different levels of antibacterial activity against WSR, with the concentration of 10-1 cfu/mL having the best control effect and a control efficiency of 61.19%. XD29-G1 has better biological control potential against wheat stripe rust.