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This paper aims to study the existence of traveling wave solutions (TWS) for a three-component noncooperative systems with nonlocal diffusion. Our main results reveal that when a threshold ℜ > 1 , there exists a critical wave speed c ∗ > 0. By using sub- and super-solution methods and Schauder's fixed point theorem, we prove that the system admits a nontrivial TWS for each c ≥ c ∗ . Meanwhile, we show that there exists no nontrivial TWS for c < c ∗ by detailed analysis. Finally, we apply our results to a nonlocal diffusive epidemic model with vaccination, and the boundary asymptotic behavior of TWS for the special case is obtained by constructing a suitable Lyapunov functional. Our research provides some insights on how to deal with the problem of TWS for the nonlocal diffusive epidemic models with bilinear incidence, which extends some results in the previous studies. [ABSTRACT FROM AUTHOR]

The number of chromosomes varies tremendously across species. It is not clear whether having more or fewer chromosomes could be advantageous. The probability of non-disjunction should theoretically decrease with smaller karyotypes, but too long chromosomes should enforce spatial constraint for their segregation during the mitotic anaphase. Here, we propose a new experimental cell system to acquire novel insights into the mechanisms underlying chromosome segregation. We collected the endemic Australian ant Myrmecia croslandi, the only known species with the simplest possible karyotype of a single chromosome in the haploid males (and one pair of chromosomes in the diploid females), since males are typically haploid in hymenopteran insects. Five colonies, each with a queen and a few hundreds of workers, were collected in the Canberra district (Australia), underwent karyotype analysis to confirm the presence of a single pair of chromosomes in worker pupae, and were subsequently maintained in the laboratory in Paris (France). Starting from dissociated male embryos, we successfully conducted primary cell cultures comprised of single-chromosome cells. This could be developed into a unique model that will be of great interest for future genomic and cell biology studies related to mitosis. [ABSTRACT FROM AUTHOR]

In aquaculture, the cost of feeding is the main factor affecting the efficiency of breeding, accounting for 40 to 80 percent of the total cost. Therefore, how to do scientific feeding is the key to reducing the cost of breeding and increase the economic benefits of breeding. Intelligent feeding is a feeding method of using all kinds of sensors to get the global information in the process of feeding, and combining with the relevant algorithm and model, the information is fed back to the control system to adjust the feeding strategy. It is also an effective means to achieve scientific feeding and improve efficiency. In recent years, some achievements have been made in the research of intelligent feeding in aquaculture, but there are still challenges in the realization of intelligent feeding due to many uncertain factors in aquaculture. The research status of automatic feeding machine and automatic feeding system is introduced. The intelligent feeding methods based on machine vision, acoustics, water quality parameters and biological model are summarized, the advantages and disadvantages of these methods are also summarized. In the future, in order to improve the accuracy of feeding intensity assessment and the adaptability of the intelligent feeding system to the breeding environment, we should strengthen the comprehensive analysis and application of the information such as image, voice, environmental factors and biological models in the process of fish feeding. [ABSTRACT FROM AUTHOR]

In this paper, stochastic analysis of interaction between palm leaf and caterpillar life-cycle is presented analytically and numerically. Existence, stabilities and extinction are analysed theoretically. Further, the results explained theoretically are simulated by using numerical representation. [ABSTRACT FROM AUTHOR]

This article discusses the importance of using a standardized synthetic microbial community, such as the oligo-mouse-microbiota (OMM12), in zebrafish models for research purposes. It highlights the advantages of the OMM12 consortium and explores the potential use of other synthetic microbiota in zebrafish research. The article also mentions the benefits of using zebrafish as a model organism in scientific research, including their external embryonic development, well-developed immune system, and anatomical and genetic similarities to humans. It discusses the challenges of developing a synthetic microbial community for zebrafish and provides a list of references related to the study of gut microbiota in zebrafish and other animal models. These references cover various topics, including the diversity of gut microbiota in zebrafish, the use of zebrafish as a model for studying xenobiotics and toxic agents, and the impact of probiotics on the gut microbiota. Overall, this article and the accompanying references provide valuable information for researchers interested in studying the gut microbiota and its role in various biological processes. [Extracted from the article]

Metal-based nanomaterials (MNMs) possess exceptional properties that have led to their widespread use in various fields, including medicine, energy, electronics, and agriculture. However, this increased utilization of MNMs also raises concerns about their potential release into environmental compartments, such as soil, water bodies, and the atmosphere, which could adversely affect the environmental system and living organisms. Hence, it is crucial to investigate the environmental risks associated with MNMs. This review comprehensively discusses the adverse effects of MNMs at different levels, including organismal, tissue, metabolic, molecular, and genetic levels. Additionally, it offers a holistic perspective on their overall impact. Specifically, biological models are categorized based on the environmental medium, and the effects of MNMs on tissues, organs, growth, development, and reproduction of individual biological models are summarized. Furthermore, the mechanisms underlying the toxicity of different MNMs toward biological models are also discussed. By doing so, this review provides a comprehensive and system-level understanding of nanotoxicity. [ABSTRACT FROM AUTHOR]

Background. Modeling allows investigating both existing and predicted processes and is widely used in basic science and in many industries. The aim is to develop a mathematical model for determining the size of the foreign bodies (FB) and their radiographic density in non-biological and biological models to improve the results of diagnosis for gunshot ricochet wounds. Materials and methods. In the biological non-living model (a piece of pork) and non-biological models (polystyrene, foam rubber), we place the FB made of paper, leather, rubber, plastic, and lithium-ion batteries. The number of the FB is 9 of each type. Number of models is 3 each: pork, polystyrene, foam rubber. We measure the dimensions of the FB and models with a metric ruler. For each model, we select the FB, which we label with the study number. We immerse the FB to the same depth using a Billroth general surgical medium hemostatic clamp in the following sequence: paper, leather, rubber, plastic, and lithium-ion battery. Multislice computed tomography (MSCT) of the models is performed on the Revolution EVO (2021) apparatus with measurement of the sizes and radiographic density of the FB and models. Radiographic density was measured in conventional units on the Hounsfield scale. For each study group, the ratio of the actual sizes of the removed FB and according to MSCT data was determined in the MathCad 15 computer math software, depending on the radiological density of the FB and the model. Results. According to MSCT data, the radiographic density of the models on the Hounsfield scale is as follows: polystyrene — –990.0 ± 0.3 units; foam rubber — –985.0 ± 0.2 units; pork — 62.0 ± 0.3 units; radiographic density of the foreign bodies: paper — –743.0 ± 10.3 units, leather — –258.0 ± 14.2 units, rubber — –12.0 ± 2.6 units, plastic — 183.0 ± 14.6 units, lithium-ion batteries — 3071 units. Visualization of paper in non-biological and biological models and leather in non-biological models is problematic due to the similar radiographic density of the models and the inability to measure the dimensions. When the FB (rubber, plastic, battery) is immersed in polystyrene, the coefficient of length (CL) is 1.0612, the coefficient of width (CW) is 1.928; in foam rubber: CL is 0.9926, CW is 1.9641; in pork: CL is 0.8394, CW is 1.534. Comparing the average coefficients of the ratio (CL and CW), we find that the coefficient in a biological model is closest to 1. This means that the FB from rubber, plastic, and batteries are best detected in pork. Conclusions. The actual dimensions of the FB placed in biological and non-biological models differ from those obtained by MSCT. Data correction is performed through calculated coefficients for length and width. The radiographic density of the model affects the radial visualization of the FB. The use of mathematical modeling in determining the sizes and radiographic density allows reducing the measurement error and determine the structure of the FB.

Cell lines are important bioresources to study the key biological processes in the areas like virology, pathology, immunology, toxicology, biotechnology, endocrinology and developmental biology. Cell lines developed from fish organs are utilized as a model in vitro system in disease surveillance programs, pharmacology, drug screening and resolving cases of metabolic abnormalities. During last decade, there were consistent efforts made globally to develop new fish cell lines from different organs like brain, eye muscles, fin, gill, heart, kidney, liver, skin, spleen, swim bladder, testes, vertebra etc. This increased use and development of cell lines necessitated the establishment of cell line depositories to store/preserve them and assure their availability to the researchers. These depositories are a source of authenticated and characterized cell lines with set protocols for material transfer agreements, maintenance and shipping as well as logistics enabling cellular research. Hence, it is important to cryopreserve and maintain cell lines in depositories and make them available to the research community. The present article reviews the current status of the fish cell lines available in different depositories across the world, along with the prominent role of cell lines in conservation of life on land or below water. [ABSTRACT FROM AUTHOR]

Degeneration of the intervertebral disc (IVD) results in a range of symptomatic (i.e., painful) and asymptomatic experiences. Components of the degenerative environment, including structural disruption and inflammatory cytokine production, often correlate with pain severity. However, the role of inflammation in the activation of pain and degenerative changes has been complex to delineate. The most common IVD injury model is puncture; however, it initiates structural damage that is not representative of the natural degenerative cascade. In this study, we utilized in vivo injection of lipopolysaccharide (LPS), a pro‐inflammatory stimulus, into rat caudal IVDs using 33G needles to induce inflammatory activation without the physical tissue disruption caused by puncture using larger needles. LPS injection increased gene expression of pro‐inflammatory cytokines (Tnfa, Il1b) and macrophage markers (Inos, Arg1), supported by immunostaining of macrophages (CD68, CCR7, Arg1) and systemic changes in blood cytokine and chemokine levels. Disruption of the IVD structural integrity after LPS injection was also evident through changes in histological grading, disc height, and ECM biochemistry. Ultimately, intradiscal inflammatory stimulation led to local mechanical hyperalgesia, demonstrating that pain can be initiated by inflammatory stimulation of the IVD. Gene expression of nociceptive markers (Ngf, Bdnf, Cgrp) and immunostaining for neuron ingrowth (PGP9.5) and sensitization (CGRP) in the IVD were also shown, suggesting a mechanism for the pain exhibited. To our knowledge, this rat IVD injury model is the first to demonstrate local pain behavior resulting from inflammatory stimulation of caudal IVDs. Future studies will examine the mechanistic contributions of inflammation in mediating pain. [ABSTRACT FROM AUTHOR]

The lack of economic funds commonly represents a limiting factor in scientific research and prevents scientists from developing brilliant ideas. Indeed, a new project may involve using appropriate scientific instruments and concurrently dealing with the costs before pursuing new research fields. The innovative concept of investigating the effects of electric fields, as a simulation of marine electrical pollution, on benthic organisms such as foraminifera (marine protozoa) has been recently explored by our research group. This pioneering research has resulted in the development of a cost-effective instrument capable of generating customized electric stimulation patterns with accuracy and reliability. Here, we describe the construction of a low-intensity electrical stimulator based on an Arduino programmable board and a few electronic components. The instrument results very stable and precise regarding the stimulation times and the regulation of the current intensity applied to the biological preparation. Moreover, the setup can stimulate the preparation in constant or pulsed direct current. This homemade stimulation apparatus can be improved or modified according to the researchers’ needs, as possibilities and fields of application can be innumerable.

This article explores numerically the biotechnological performances of microalgae biofaçade. The model computes the system's thermal behavior using a radiative-convective approach accounting for location on Earth and actual weather data. In a coupled manner, it simulates the microalgae culture behavior, i.e. light-driven growth and cell pigment content acclimation. In addition, it features refinement such as wavelength-dependent biomass optical properties and thermal-modulated biological rates. Thanks to this model, operation strategies and design possibilities were evaluated using actual weather data for a biofaçade module deployed in Marseille in 2023. Investigations revealed that a semi-batch mode of operation, while simplistic, is the most efficient way to operate a biofaçade if sole biological production is considered (about 18.0 ± 0.9 kg per year, 2.44 ± 0.12 g/L output concentration). However, if intended as an office glazing, turbidostat mode of operation should be preferred for aesthetic and visual comfort reasons (about 19.1 ± 1.1 kg per year, 0.64 ± 0.07 g/L output concentration). System optimization also confirmed the experimental observation that the system could be prone to overheating. Nevertheless, while overheating can be mitigated by increasing the reservoir thickness, this strategy is detrimental to the average output concentration. Finally, location-specific optimization revealed that a standard biofaçade module could be deployed over France, and system performances are derived for the whole country thanks to the weather forecast agency data. [Display omitted] • Biofaçades are considered a potential synergy between buildings and microalgae. • A model coupling weather, illumination, temperature, and cell growth was used to describe system behavior. • Bioprocess control procedures (semi-batch, turbidostat, continuous) are investigated. • Particle Swarm Optimizer coupled with a Genetic Algorithm is used to optimized the system. • Biofaçade module standardization can be envisioned with minimal impact on biotechnological performances. [ABSTRACT FROM AUTHOR]

A meta-analytic approach deciphered the taxonomic profile of the zebrafish gut microbiota at different developmental stages. Data (16S rDNA) were systematically searched in databases, selecting those with intestine samples of fish not exposed to a particular treatment or challenge (e.g., pathogens, dietetic tests, xenobiotics, etc.) and obtaining 340 samples to be processed. Results revealed marked differences between the developmental phases. Proteobacteria was the dominant phylum in the larval phase, with a relative abundance of 90%, while the rest of the phyla did not exceed 2%. Vibrio, Aeromonas, Plesiomonas, Pseudomonas, Shewanella, and Acinetobacter were the dominant genera in this phase. Transitional changes were observed after the larvae stage. Proteobacteria still registered high abundance (48%) in the juvenile phase, but Fusobacteria (40%) and Bacteriodota (5.9%) registered considerable increases. Genera, including Cetobacterium, Plesiomonas, Aeromonas, Vibrio, and Flavobacterium, dominated this stage. The phyla Proteobacteria (48%) and Fusobacteria (35%) were strongly established in the adult phase. Cetobacterium was registered as the most abundant genus, followed by Aeromonas, Acinetobacter, Plesiomonas, Vibrio, and ZOR0006 (Firmicutes; 6%). In conclusion, the composition of the intestinal microbiota of zebrafish is consistently determined by two primary phyla, Proteobacteria and Fusobacteria; however, this composition varies depending on the developmental stage. Cetobacterium and Aeromonas are the most relevant genera in juveniles and adults. Finally, these results reveal a consistent pattern of certain bacterial groups in the zebrafish microbiota that could help shape gnotobiotic models (colonized with a specific known bacterial community) or synthetic microbiota (in vitro assembly of microbes), among other approaches. [Display omitted] • Zebrafish gut microbiota relies on its developmental stage. • Vibrio and Aeromonas play a major role in the larval zebrafish gut microbiota. • Cetobacterium has a relevant role in the juvenile and adult zebrafish microbiota. [ABSTRACT FROM AUTHOR]

Background and Objectives: Effective microsurgical training necessitates dedicated practice, prompting the development of simulation models that mitigate the hygiene risks, regulatory challenges, and storage difficulties associated with conventional biological models. This study aims to evaluate the preferences of microsurgeons and medical students regarding self-made silicone simulation vessels, comparing them to standard biological models., Methods: A three-part jig, comprising of a two-part metal clamp component and a transparent acrylic block with 4x4 channels, was designed. This assembly produced 16 vessels with a 1 ​mm inner diameter. Liquid silicone (Ecoflex 00-30), readily accessible from online distributors, was injected into the channels using a syringe. After tightening the clamp component and inserting 16 1 ​mm k-wires, the vessels were left to set for approximately 24 ​h 20 medical students with no prior microsurgical experience and 10 microsurgery-trained surgeons then evaluated these silicone vessels against a commonly used biological model (chicken brachial artery for surgeons or chicken aorta for students). Participants were then surveyed about their preference for a specific model for frequent practice using a 10-point Likert scale., Results and Conclusion: In assessing ideal microsurgical training models, all participants highlighted the importance of realism. Surgeons' main practical considerations were hygiene, availability, and setup and storage ease, while medical students were primarily concerned with cost-effectiveness. Both surgeons and medical students perceived the biological model as more realistic, yet less hygienic and harder to set up and store. Conversely, the silicone model, though deemed less realistic, offered advantages in hygiene, availability, cost-effectiveness, and setup and storage simplicity. The silicone model emerged as the overall favorite amongst all participants for frequent practice. Silicone vessels may serve as a complementary adjunct to biological models, allowing surgeons-in-training to practice their skills outside of the operating room and lab settings., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Society for Indian Hand Surgery and Micro Surgeons. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.)

Thimerosal (TM) is a toxic, organometallic mercury compound (which releases ethyl-mercury-containing compounds in aqueous solutions) used as a preservative in vaccines. Mitochondria are organelle which are highly vulnerable to many chemical compounds, including mercury (Hg) and its derivatives. Wistar rats (at 21 days of age) were used to model a child's TM exposure following childhood vaccination, divided in two groups: TM exposed (20 μg/kg/day) and unexposed controls (saline solution), both for 24 h. Atomic Fluorescence Spectrometry was used to quantify the amounts of mercury in tissues. The electron transport chain (ETC) from isolated mitochondria was evaluated using an oxygen electrode. The mitochondrial membrane potential and H 2 O 2 production were analyzed using selective fluorescence probes. The activity of some enzymes (SOD, CAT, GPx, and AChE) and secondary markers of oxidative stress (GSH, GSSG, total free thiol) were also examined in tissues. Hg accumulation in the brain and liver was higher in exposed animals when compared to the control. Liver-isolated mitochondria showed that TM improved respiratory control by 23%; however, states 3 and 4 of the ETC presented a decrease of 16% and 37%, respectively. Furthermore, brain-isolated mitochondria presented an improvement of 61% in respiratory control. Brain enzyme activities were significantly impacted in TM-exposed rats compared to unexposed rats as follows: decreases in SOD (32%) and AChE (42%) and increases in GPx (79%) and CAT (100%). GPx enzyme activity in the liver was significantly increased (37%). Among secondary oxidative stress markers, the brain's total reduced thiol (SH) concentration was significantly increased (41%). Acute TM treatment exposure in a Wistar rat model mimicking TM exposure in an infant following childhood vaccination significantly damaged brain bioenergetic pathways. This study supports the ability of TM exposure to preferentially damage the nervous system. [Display omitted] • Thimerosal (TM) significantly affects mitochondrial bioenergetics in the brain. • Mitochondrial integrity (membrane potential) was maintained after acute TM treatment. • Ethylmercury released after the breakdown of TM compromised the cholinergic system. • The brain is more sensitive to oxidative stress induced by TM compared to the liver. [ABSTRACT FROM AUTHOR]

Objective. Treatment plans of ion-beam therapy have been made under an assumption that all cancer cells within a tumour equally respond to a given radiation dose. However, an intra-tumoural cellular radiosensitivity heterogeneity clearly exists, and it may lead to an overestimation of therapeutic effects of the radiation. The purpose of this study is to develop a biological model that can incorporate the radiosensitivity heterogeneity into biological optimization for ion-beam therapy treatment planning. Approach. The radiosensitivity heterogeneity was modeled as the variability of a cell-line specific parameter in the microdosimetric kinetic model following the gamma distribution. To validate the developed intra-tumoural-radiosensitivity-heterogeneity-incorporated microdosimetric kinetic (HMK) model, a treatment plan with H-ion beams was made for a chordoma case, assuming a radiosensitivity heterogeneous region within the tumour. To investigate the effects of the radiosensitivity heterogeneity on the biological effectiveness of H-, He-, C-, O-, and Ne-ion beams, the relative biological effectiveness (RBE)-weighted dose distributions were planned for a cuboid target with the stated ion beams without considering the heterogeneity. The planned dose distributions were then recalculated by taking the heterogeneity into account. Main results . The cell survival fraction and corresponding RBE-weighted dose were formulated based on the HMK model. The first derivative of the RBE-weighted dose distribution was also derived, which is needed for fast biological optimization. For the patient plan, the biological optimization increased the dose to the radiosensitivity heterogeneous region to compensate for the heterogeneity-induced reduction in biological effectiveness of the H-ion beams. The reduction in biological effectiveness due to the heterogeneity was pronounced for low linear energy transfer (LET) beams but moderate for high-LET beams. The RBE-weighted dose in the cuboid target decreased by 7.6% for the H-ion beam, while it decreased by just 1.4% for the Ne-ion beam. Significance. Optimal treatment plans that consider intra-tumoural cellular radiosensitivity heterogeneity can be devised using the HMK model., (© 2024 Institute of Physics and Engineering in Medicine.)