Stability Analysis of a Hybrid Cellular Automaton Model of Cell Colony Growth

Cell colonies of bacteria, tumour cells and fungi, under nutrient limited growth conditions, exhibit complex branched growth patterns. In order to investigate this phenomenon we present a simple hybrid cellular automaton model of cell colony growth. In the model the growth of the colony is limited by a nutrient that is consumed by the cells and which inhibits cell division if it falls below a certain threshold. Using this model we have investigated how the nutrient consumption rate of the cells affects the growth dynamics of the colony. We found that for low consumption rates the colony takes on a Eden-like morphology, while for higher consumption rates the morphology of the colony is branched with a fractal geometry. These findings are in agreement with previous results, but the simplicity of the model presented here allows for a linear stability analysis of the system. By observing that the local growth of the colony is proportional to the flux of the nutrient we derive an approximate dispersion relation for the growth of the colony interface. This dispersion relation shows that the stability of the growth depends on how far the nutrient penetrates into the colony. For low nutrient consumption rates the penetration distance is large, which stabilises the growth, while for high consumption rates the penetration distance is small, which leads to unstable branched growth. When the penetration distance vanishes the dispersion relation is reduced to the one describing Laplacian growth without ultra-violet regularisation. The dispersion relation was verified by measuring how the average branch width depends on the consumption rate of the cells and shows good agreement between theory and simulations.Comment: 8 pages, 6 figure

Comparative risks of initial aortic events associated with genetic thoracic aortic disease

BACKGROUND: Pathogenic variants in 11 genes predispose individuals to heritable thoracic aortic disease (HTAD), but limited data are available to stratify the risk for aortic events associated with these genes. OBJECTIVES: This study sought to compare the risk of first aortic event, specifically thoracic aortic aneurysm surgery or an aortic dissection, among 7 HTAD genes and variant types within each gene. METHODS: A retrospective cohort of probands and relatives with rare variants in 7 genes for HTAD (n = 1,028) was assessed for the risk of first aortic events based on the gene altered, pathogenic variant type, sex, proband status, and location of recruitment. RESULTS: Significant differences in aortic event risk were identified among the smooth muscle contraction genes (ACTA2, MYLK, and PRKG1; P = 0.002) and among the genes for Loeys-Dietz syndrome, which encode proteins in the transforming growth factor (TGF)-β pathway (SMAD3, TGFB2, TGFBR1, and TGFBR2;P \u3c 0.0001). Cumulative incidence of type A aortic dissection was higher than elective aneurysm surgery in patients with variants in ACTA2, MYLK, PRKG1, and SMAD3; in contrast, patients with TGFBR2 variants had lower cumulative incidence of type A aortic dissection than elective aneurysm surgery. Cumulative incidence of type B aortic dissection was higher for ACTA2, PRKG1, and TGFBR2 than other genes. After adjusting for proband status, sex, and recruitment location, specific variants in ACTA2 and TGFBR2 were associated with substantially higher risk of aortic event with childhood onset. CONCLUSIONS: Gene- and variant-specific data on aortic events in individuals with HTAD support personalized aortic surveillance and clinical management

Control of Ground Movements for a Multi-Level-Anchored, Diaphragm Wall During Excavation

An excavation up to 23m deep for the Dana Farber research tower in the Longwood medical area of Boston, was supported by a permanent perimeter diaphragm wall extending into the underlying conglomerate and up to 6 levels of prestressed tiebacks anchored in the rock. The lateral earth support system was very successful in limiting wall deflections to less than ±15mm on each of the four sides of the excavation. However, ground surface settlements up to 65mm occurred on two sides and were attributed to ground losses that occurred when tiebacks were installed through overpressured sand layers at depths of 15-18m. Finite element simulations are able to describe consistently the effects of the different excavation and support sequences on each side of the project using backfigured soil properties, while surface settlements can be explained by including local ground losses within the analyses

Factores de riesgo asociados a gangrena de Fournier: Risk factors associated to Fournier gangrena

Introducción:Fournier gangrene is a necrotizing fasciitis that affects the perineal, perianal, genital and lower third of the abdomen that leads to necrosis and gangrene of the underlying tissue and compromises in a fulminating and progressive way the life of the patient. It is considered that there are various factors that favor its appearance. The objective of this article is to carry out an in-depth review of risk factors and predisposing conditions of Fournier's gangrene during the last years. Methods: A systematic review of scientific articles, clinical reviews and case reports; both in Spanish and English, related to the subject. The search sources used were: Google Scholar, ScienceDirect - Elsevier library, PubMed, Scielo. For this review, the published articles that had investigative and theoretical-conceptual experiences from 2008 to the present. Results: Based only on 21 of the reviewed articles, it was evidenced that the great majority of patients were male because they were a group of risk, and had an important underlying organic condition; highlighting diabetes mellitus, chronic alcoholism, immunosuppression and other comorbidities. Conclusion: Fournier's gangrene is an entity that can be lethal, which is favored by different risk factors, whose triggering cause is a disease debilitating as well as perirectal or urogenital conditions that have not been treated correctly. Due to its severe prognosis, an early diagnosis with a good management of the risk factors and a Appropriate, early and aggressive multidisciplinary intervention are essential for a good evolution.     DOI 10.25176/RFMH.v18.n4.1736Introducción: La gangrena de Fournier es una fascitis necrotizante que afecta la región perineal, perianal,genital y del tercio inferior del abdomen que lleva a necrosis y gangrena del tejido subyacente y compromete de manera fulminante y progresiva la vida del paciente. Se considera que hay diversos factores que favorecen su aparición. El objetivo de este artículo es realizar una revisión profunda sobre los factores de riesgo y las afecciones predisponentes de la gangrena de Fournier durante los últimos años. Métodos: Se realizó una revisión sistemática de artículos científicos, revisiones clínicas e informes de casos; tanto en español como en inglés, relacionados con el tema. Las fuentes de búsqueda empleadas fueron: Google Scholar, ScienceDirect – Elsevier library, PubMed, Scielo. Para esta revisión se seleccionaron los artículos publicados que tuvieron experiencias investigativas y teórico-conceptuales desde el 2008 a la actualidad. Resultados: Basado sólo en 21 de los artículos revisados, se evidenció que la gran mayoría de pacientes eran varones por ser un grupo de riesgo, y tenían una importante afección orgánica de base; destacando la diabetes mellitus, alcoholismo crónico, inmunosupresión y otras comorbilidades. Conclusión: La gangrena de Fournier es una entidad que puede ser letal, que está favorecida por distintos factores de riesgo, cuya causa desencadenante es una enfermedad debilitante así como también afecciones perirrectales o urogenitales que no han sido tratadas correctamente. Debido a su pronóstico grave, un diagnóstico temprano con un buen manejo de los factores de riesgo y una intervención multidisciplinaria adecuada, temprana y agresiva son esenciales para una buena evolución.   DOI 10.25176/RFMH.v18.n4.173

Potential Evaluation of a Locally-Designed Wind-Pump System for Water Pumping to Irrigate Rice Crop Based on a Ten-Year Weather Data in the Philippines

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An Overview of the Downdraft Rice Husk Gasifier Technology for Thermal and Power Applications

An overview of the downdraft rice husk gasifier (DDRHG) for thermal and power applications is herein presented. The different designs of the downdraft rice husk gasifier with reactor diameter ranging from 0.10 meter to 1.20 meter are discussed in detail. Smaller units of the DDRHG were found to have performed well in fixed bed. Larger units of the gasifier, on the other hand, are suited for moving-bed type making possible continuous operation without discharging and recharging the reactor. Present thermal applications of the gasifier includes: domestic cookstove, bakery oven, dryers, rotary kiln, steam boiler, and torrefyer. The DDRHG is also used to run surplus gasoline engines for driving water pump, micro-mill, and electric generator without any modification. The advantages and limitations of the gasifier as well as its environmental and socio-economic benefits over the use of conventional fossil-fueled systems are enumerated. At present, the investment cost for the gasifier ranges from PHP2,000 to 2,500.00 (USD 1 = PHP40.00) per kWt for thermal application and PHP20,000.00 to 30,000 per kWe for power generation. The cost of using the gasifier is much cheaper than that of the conventional fossil fuel and the investment can be recovered in a shorter period

Bases for the digital transformation of the productive sector: an exploratory study of key competencies in Peru

The main objective of this research is to determine the basis of the key competencies necessary to achieve the digital transformation of public and private organizations in Peru. With this objective in mind, the conceptual framework involves the definition of a digital transformation in organizations and their impact on those organizations. Secondly, the article presented the results of the exploratory fieldwork conducted through in-depth interviews with ten executives from different productive sectors and analyzed them through content analysis. From this exploratory study, it concludes that all the experts interviewed agree on: i) the urgency of initiating a digital transformation process in small, medium, and large companies; ii) the need for training in digital transformation for company employees in all functional lines, giving priority to the commercial area; and iii) investment in the implementation process starting with cybersecurity and big data due to the impact on the operational and commercial results of the companies.El objetivo principal de esta investigaci?n es determinar las bases de las competencias clave necesarias para lograr la transformaci?n digital de las organizaciones p?blicas y privadas en el Per?. Con este objetivo en mente, el marco conceptual implica la definici?n de la transformaci?n digital en las organizaciones y su impacto en las mismas. En segundo lugar, el art?culo presenta los resultados del trabajo de campo exploratorio realizado a trav?s de entrevistas en profundidad a diez ejecutivos de diferentes sectores productivos y los analiza a trav?s del an?lisis de contenido. De este estudio exploratorio se concluye que todos los expertos entrevistados coinciden en: i) la urgencia de iniciar un proceso de transformaci?n digital en las peque?as, medianas y grandes empresas; ii) la necesidad de formaci?n en transformaci?n digital para los empleados de las empresas en todas las l?neas funcionales, priorizando el ?rea comercial; y iii) la inversi?n en el proceso de implantaci?n a partir de la ciberseguridad y el big data por el impacto en los resultados operativos y comerciales de las empresas

Flowshop with additional resources during setups: Mathematical models and a GRASP algorithm

[EN] Machine scheduling problems arise in many production processes, and are something that needs to be consider when optimizing the supply chain. Among them, flowshop scheduling problems happen when a number of jobs have to be sequentially processed by a number of machines. This paper addressees, for the first time, the Permutation Flowshop Scheduling problem with additional Resources during Setups (PFSR-S). In this problem, in addition to the standard permutation flowshop constraints, each machine requires a setup between the processing of two consecutive jobs. A number of additional and scarce resources, e.g. operators, are needed to carry out each setup. Two Mixed Integer Linear Programming formulations and an exact algorithm are proposed to solve the PFSR-S. Due to its complexity, these approaches can only solve instances of small size to optimality. Therefore, a GRASP metaheuristic is also proposed which provides solutions for much larger instances. All the methods designed for the PFSR-S in this paper are computationally tested over a benchmark of instances adapted from the literature. The results obtained show that the GRASP metaheuristic finds good quality solutions in short computational times.Juan C. Yepes-Borrero acknowledges financial support by Colfuturo under program Credito-Beca grant number 201503877 and from ElInstituto Colombiano de Credito Educativo y Estudios Tecnicos en el Exterior - ICETEX under program Pasaporte a la ciencia - Doctor-ado, Foco-reto pais 4.2.3, grant number 3568118. This research hasbeen partially supported by the Agencia Estatal de Investigacion (AEI)and the European Regional Development's fund (ERDF): PID2020-114594GB-C21; Regional Government of Andalusia: projects FEDER-US-1256951, AT 21_00032, and P18-FR-1422; Fundacion BBVA: project Netmeet Data (Ayudas Fundacion BBVA a equipos de investigacioncientifica 2019). The authors are partially supported by Agencia Valenciana de la Innovacion (AVI) under the project ireves (innovacionen vehiculos de emergencia sanitaria): una herramienta inteligente dedecision'' (No. INNACC/2021/26) partially financed with FEDER funds(interested readers can visit http://ireves.upv.es), and by the Spanish Ministry of Science and Innovation under the project OPRES-RealisticOptimization in Problems in Public Health'' (No. PID2021-124975OB-I00), partially financed with FEDER funds. Part of the authors aresupported by the Faculty of Business Administration and Managementat Universitat Politecnica de ValenciaYepes-Borrero, JC.; Perea, F.; Villa Juliá, MF.; Vallada Regalado, E. (2023). Flowshop with additional resources during setups: Mathematical models and a GRASP algorithm. Computers & Operations Research. 154. https://doi.org/10.1016/j.cor.2023.10619215

Development of a Hydrous Ethanol Fuel Feeding Device for Spark-Ignition Engine

While the Philippine Biofuels Act of 2006 mandates the use of anhydrous bioethanol as blend for gasoline, the potential of hydrous ethanol as an alternative fuel for spark-ignition engines has not been fully realized. This study explored the possibility of using hydrous ethanol as fuel for spark-ignition engines with minimal modifications and without the need for gasoline blend. A fuel feeding device was developed to feed hydrous ethanol fuel into the intake manifold of the engine, bypassing the carburetor. By replacing the components that are not compatible with hydrous ethanol and installing a fuel feeding device developed at PhilRice, two spark-ignition engines were able to run solely on 80-95% hydrous ethanol fuel. The fuel economy was found to be a significant issue in the utilization of hydrous ethanol fuel as there is a 75% increase in fuel consumption when using hydrous ethanol. There is potential for hydrous ethanol to be used as fuel if it can be produced locally and sold at half the pump price of gasoline

A Liposomal Formulation to Exploit the Bioactive Potential of an Extract from Graciano Grape Pomace

Antioxidant compounds with health benefits can be found in food processing residues, such as grape pomace. In this study, antioxidants were identified and quantified in an extract obtained from Graciano red grape pomace via a green process. The antioxidant activity of the extract was assessed by the DPPH and FRAP tests, and the phenolic content by the Folin–Ciocalteu test. Furthermore, nanotechnologies were employed to produce a safe and effective formulation that would exploit the antioxidant potential of the extract for skin applications. Anthocyanins, flavan-3-ols and flavanols were the main constituents of the grape pomace extract. Phospholipid vesicles, namely liposomes, were prepared and characterized. Cryo-TEM images showed that the extract-loaded liposomes were predominantly spherical/elongated, small, unilamellar vesicles. Light scattering results revealed that the liposomes were small (~100 nm), homogeneously dispersed, and stable during storage. The non-toxicity of the liposomal formulation was demonstrated in vitro in skin cells, suggesting its possible safe use. These findings indicate that an extract with antioxidant properties can be obtained from food processing residues, and a liposomal formulation can be developed to exploit its bioactive value, resulting in a promising healthy product