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This paper investigates the dynamics of a three-dimensional nonlinear cancer model involving interactions among cancer cells, normal cells, and immune cells. By performing a linear stability analysis of the equilibria and investigating the Hopf bifurcation in relation to the immune cell growth rate, we reveal the possibility of chaotic behavior when radiation is absent. However, with the appropriate implementation of radiotherapy, the cancer model demonstrates stable solutions, transitioning from chaotic oscillations through period-halving bifurcation. Additionally, we propose and examine an indirect Z-control mechanism within the cancer model. Our findings indicate that using the indirect Z-controller on the immune population successfully manages chaos and adjusts the cancer cell density to a desired level. Through extensive investigation, we demonstrate the robustness of the Z-controller in managing oscillations and provide insights into determining the minimum number of immune cells needed to achieve a predetermined cancer cell density. This study underscores the importance of control mechanisms in mitigating cancer progression and highlights the potential of Z-control for therapeutic intervention strategies.

Firm and executive written communication allows researchers to explore firm strategy and executive personality. Two data sources have received increased interest in this matter: firm press releases and earnings call transcripts. However, while researchers can obtain these data sources through services like LexisNexis, they often come in unstructured formats that do not directly allow fine-grained quantitative analysis through statistical software. To address this challenge, we developed disclosuR, an innovative R package that transforms unstructured PDF press releases and earnings call transcripts into structured data frames, facilitating advanced text analysis. disclosuR stands out by providing unique features such as speaker-level language analysis and identifying temporal communication patterns within press releases. These functionalities empower researchers to conduct granular and reproducible quantitative analyses, significantly advancing the management literature. By enabling the seamless integration of text data into R, our package not only enhances the reproducibility of social science research but also opens new avenues for examining executive communication dynamics and strategic firm disclosures.

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  Convert LexisNexis PDFs to structured R data frames

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  Standardize text analysis of firm communication

The smallest worthwhile effect (SWE) is the smallest beneficial effect of an intervention that justifies the costs, risks, and inconveniences. The objective is to establish the SWE of spinal manipulative therapy (SMT) for the treatment of low back pain (LBP), and to gain insight into how different attributes of the treatment are traded among each other when choosing SMT. Part 1. A mixed-methods study will be conducted to establish and prioritize a list of attributes influencing choices for those who consider SMT for the treatment of LBP. Individual interviews and consensus groups with chiropractors, manual therapists, and osteopaths and their patients will be conducted. Interviews and consensus groups will be voice-recorded and transcribed verbatim. Part 2. A Discrete Choice Experiment (DCE) will be conducted among people with LBP who have limited to no experience with SMT. Participants will be recruited through an online independent panel company. The survey will consist of several choice sets with attributes and their levels established from Part 1. The DCE will be preceded by a short survey to understand the clinical aspects (i.e. presentation, history and previous treatment for LBP) as well as socio-demographic characteristics of the participants.

Measuring what people eat is a major methodological challenge. We developed and validated a new web-based method to record actual food supply data that would be less time consuming than the original method (i.e., food supply diary). Through the COD-Appro web application, participants can enter their food supplies by selecting a food item from a list based on items included in French food databases; thus automatically associated with nutrient composition and environmental impacts data. We recruited 102 participants who used COD-Appro during one month, among which 30 also used a classical paper-based food supply diary to be able to compare the two methods. A feedback questionnaire was completed by all the participants. The two methods showed no difference between the price and the quantity of food purchases when compared by food groups (n = 10) which confirms that the new method was robust compared to the original method. In addition, participants reported good usability of the COD-Appro web application and its use saved a considerable amount of time to the experimenters by integrating data entry and pairing with food databases (nutrient composition and environmental impacts) into the data collection step performed by the participants themselves.

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  Web-based food supply data collection

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  Association with nutrient composition and environmental impacts

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  External validity compared to original method (i.e., food supply diary)

Electrofishing is a common method for sampling fish in rivers. In Sweden, electrofishing has a long history, dating back to the 1950s, but the vast majority of surveys have been conducted by wading in shallow river stretches, leaving a data gap for non-wadable rivers. Boat electrofishing allows for surveys in deeper river sections, but limited numbers of operational electrofishing boats have led to standardisation of methods not being prioritized within Swedish water management. This method protocol describes the first Swedish standardised method for boat electrofishing, based on intermittent shoreline sampling in larger slow-flowing rivers. The paper describes:

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  General methodology for boat electrofishing operation

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  Data collection protocols

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  Discussion of current caveats for the method

Aquaculture is growing industry from the perspective of sustainable food fulfillment and county's economic development. Technology oriented aquafarming is the solution for effective water quality monitoring and high yield production. Internet of Things (IoT) integrated aquaculture can cater to such requirements. This research article introduces a comprehensive method aimed at seamlessly incorporate IoT sensors into aquafarming environments, utilizing Arduino boards and communication modules. The proposed method measures accurate water quality parameters, such as temperature, pH levels, and Dissolved Oxygen (DO), which are essential for maintaining optimal conditions for suitable aquaculture environment. This method enables the real-time collection of critical data points that are essential prevent fish diseases and mortality with low human intervention and maintenance cost. The key contributions of the methodology are mentioned below.

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  Design and development of a compact and efficient Printed Circuit Board (PCB) to achieve accurate sensor data readings and reliable communication in an aqua environment.

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  Prevent fish disease and mortality rate through data-driven decision incorporating correlation of DO, pH, and temperature sensor data.

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  Conducted instrument calibration checks and cross-validated automated system data with manual observations through repeatability tests to ensure precise measurements of sensor parameters.

Floods have an important impact on life and loss of goods. Urban green spaces are crucial to mitigating flood impact. However, their capacity to prevent floods depends on their condition, especially in areas highly affected by human activities such as lawns. Here, we developed a simple method to assess flood regulation using soil penetration resistance as a proxy and tested it on an urban lawn in Vilnius (Lithuania) in winter. We developed an experimental design using an app for collecting data and working with it in a GIS environment. To understand their spatial relations, geostatistical (e.g., semi-variogram model and ordinary kriging mapping) and spatial statistics ((Moran's global autocorrelation index and Cluster and Outlier Analysis (Anselin Local Moran's I)) tools were applied. The preliminary results from the tested method showed that the lawn studied has different capacities to retain floods due to the management practices. Nevertheless, it is essential to be applied in different soil moisture conditions since flood regulation (soil penetration resistance) can be variable throughout the year.

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  A novel method was developed to estimate flood regulation using soil penetration resistance as a proxy;

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  An urban lawn was used to test the method and identify areas with low and high capacity for flood regulation;

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  The method quickly assesses lawn flood retention capacity in different environments.

Geographically Weighted Regression (GWR) is one of the local statistical models that can capture the effects of spatial heterogeneity. This model can be used for both univariate and multivariate responses. However, it should be noted that GWR models require the assumption of error normality. To overcome this problem, we propose a GWR model for generalized gamma distributed responses that can capture the phenomenon of some special continuous distributions. The proposed model is known as Geographically Weighted Multivariate Generalized Gamma Regression (GWMGGR). Parameter estimation is performed using the Maximum Likelihood Estimation (MLE) method optimized with the Bernt-Hall-Hall-Haussman (BHHH) algorithm. To determine the significance of the spatial heterogeneity effect, a hypothesis test was conducted using the Maximum Likelihood Ratio Test (MLRT) approach. We made a spatial cluster based on the estimated model parameters for each response using the k-means clustering method to interpret the obtained results. Some highlights of the proposed method are:

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  A new model for GWR with multivariate generalized gamma distributed responses to overcome the assumption of normally distributed errors.

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  Goodness of fit test to test the spatial effects in GWMGGR model.

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  Spatial clustering of districts/cities in Central Java based on three dimensions of educational indicators.

The increasing global demand for house crickets (Acheta domesticus) necessitates effective health measures. Despite their abundance, the effects of gregarines on these hosts remain underexplored. We present a method for controlled gregarine infection and maintenance of gregarine-free cricket populations. This system, adapted from prior work, is essential for experiments on gregarine infection dynamics, providing insights into parasite evolution and host-parasite interactions within the Apicomplexa group. This protocol includes rearing and maintenance of gregarine-free cricket populations for experimental purposes, gregarine production for oocyst solution and cricket infection, and gregarine infection assessment.

The rumen ciliates are a diverse group of protozoa residing in the rumen of ruminant animals. They are primarily found in the orders Entodiniomorphida and Vestibuliferida, playing crucial roles in the digestion and breakdown of feed within the host's rumen, closely intertwined with the host's nutrient absorption. In vitro monocultures of representatives of rumen ciliates are important to better study them. So far, Entodinium caudatum and Epidinium caudatum, representatives of the order Entodiniomorphida, have been successfully cultivated as a monoculture in vitro. However, for the order Vestibuliferida, no representative species has been established a stable monoculture in vitro up to date, which hampers to study their physiology and metabolism. Therefore, we have developed a simple method for the in vitro cultivation of Dasytricha ruminantium, a representative rumen ciliate in the order Vestibuliferida. Utilizing an optimized culture medium with easily obtainable components, and the cultivation process is simple. This will facilitate further research in metabolism and other studies requiring large pure live materials.

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  Filtration and separation for enriching D. ruminantium.

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  A culture medium (DRM) suitable for the growth of D. ruminantium, with easily obtainable components.

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  Simple cultivation process, facilitating the obtainment of a large number of monocultured D. ruminantium.