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En el presente trabajo, se construye un modelo matemático que representa la dinámica que existe entre el fitoplancton (F), el zooplancton (Z) y la anchoveta (A) a partir del modelo de Samares y Anal. Esta cadena alimenticia se presenta en el área marítima peruana donde se encuentra un ecosistema de tres eslabones, además que la cadena alimenticia es un eje principal en el equilibrio ecológico dentro del mar. Se estudiará el comportamiento de las poblaciones (especies marítimas) donde se determinará la estabilidad del modelo (criterio de Routh-Hurwitz) en el largo plazo, donde se analizará con el criterio de Dulac-Bendixon para evaluar la existencia de órbitas periódicas cerradas. Y las respectivas simulaciones computacionales para complementar el estudio e interpretar las situaciones que afectan al ecosistema marítimo.

Background and Objectives: The acute acute delirious puff named BDA in french, from French psychiatric nosology, is similar to schizophreniform disorder (CIM) and brief psychotic disorder (DSM). In Africa, its prevalence is between 11.34% and 32% [3-5]. The aim of our study was to determine the epidemiological and clinical and characteristics of BDA in hospitalization at the Psychiatric Center of Ziguinchor. Methodology: It was a retrospective, descriptive study carried out at the Emile Badiane Psychiatric Center (CPEB) in Ziguinchor, which focused on the records of patients followed in this center from January 1, 2014 to December 31, 2019. All patients hospitalized for BDA during the study period were included. Results: In total out of 1370 hospitalizations recorded, 400 were for BDA, i.e. a hospital prevalence of 29.1%. Men represented 67.9% of the workforce. The mean age was 32.09 ± 11.62 years. The age group [20 to 39] represented 68% of the workforce. Family psychiatric history was found in 33.8% of cases. Hospitalization in the first month following the onset of the disease occurred in 54.7% of cases. Cannabis consumption was found in 102 cases, polymorphic delirium in 55.6%, persecution in 92,6% and the hallucinatory mechanism in 51.7%. Behavioral disorder was noted in 86.2% of our patients, including 28.3% physical and/or verbal aggression. The average duration of hospitalization was 19.75 ± 8.9 days with extremes of 2 and 62 days. Normal output was 89.7%. Persistence of delirium at discharge was noted in 30 patients (8.8%). Neuroleptics were used in 33.2% of cases. Conclusion: Our study confirms the prevalence of BDA in Africa which remains high. It occurs in a young adult, male, single, educated, unemployed and with a family psychiatric history. It is characterized by a predominantly “persecutive” polymorphic delirium with a hallucinatory mechanism responding favorably to neuroleptics after a 19-day hospital stay. It also shows the need to encourage the proliferation of psychiatric care centers such as that of Ziguinchor, which draws a good part of the patients from the south of the country.

En este trabajo se realizo un modelo computacional a traves de los Automatas Celulares que puede describir la dinamica de como se propagan las enfermedades de transmision de sexual considerando una subclasificacion para la poblacion de infectados (curable y no curable). Asi mismo, se ha considerado en este trabajo la perspectiva de la epidemiologia matematica del modelo matematico SIS de W.O. Kermack y A.G. McKendrick que representa la dinamica de la epidemia, siendo posible asi analizar el comportamiento de la propagacion de la epidemia en el tiempo.

Resumen En el presente trabajo, se construye un modelo matemático que representa la dinámica que existe entre el fitoplancton (F), el zooplancton (Z) y la anchoveta (A) a partir del modelo de Samares y Anal. Esta cadena alimenticia se presenta en el área marítima peruana donde se encuentra un ecosistema de tres eslabones, además que la cadena alimenticia es un eje principal en el equilibrio ecológico dentro del mar. Se estudiará el comportamiento de las poblaciones (especies marítimas) donde se determinará la estabilidad del modelo (criterio de Routh-Hurwitz) en el largo plazo, donde se analizará con el criterio de Dulac-Bendixon para evaluar la existencia de órbitas periódicas cerradas. Y las respectivas simulaciones computacionales para complementar el estudio e interpretar las situaciones que afectan al ecosistema marítimo. Abstract In the present work, a mathematical model is built that represents the dynamics that exist between phytoplankton (F), zooplankton (Z) and anchovy (A) from the model of Samares and Anal. This food chain occurs in the Peruvian maritime area where there is a three-link ecosystem, in addition to the fact that the food chain is a main axis in the ecological balance within the sea. The behavior of the populations (maritime species) will be studied where the stability of the model (Routh-Hurwitz criterion) in the long term will be determined, where it will be analyzed with the Dulac-Bendixon criterion to evaluate the existence of closed periodic orbits. And the respective computational simulations to complement the study and interpret the situations that affect the maritime ecosystem.

The accelerated approval pathway has been criticized recently for employing lower regulatory standards than traditional drug approval, undue delays in withdrawing approvals of drugs for which studies have not confirmed clinical benefit, and confirmatory trials not being pursued with due diligence. This article examines the status of confirmatory studies of drugs approved under the US Food and Drug Administration’s (FDA’s) accelerated approval program between December 1992 and December 2021. It includes background on the program and provides broader context about the program’s performance to date over its 30-year history. Our analysis demonstrates that the accelerated approval program has been largely successful, with half of accelerated approvals converted to traditional approval in a median time of 3.2 years. Furthermore, recent FDA actions show that the agency is appropriately managing the program when a drug approved under accelerated approval fails to confirm a clinical benefit. Any proposed changes to the program should be based on cumulative experience with the program, rather than outliers.

The present study proposes the use of a segmented SIR-D mathematical model to predict the evolution of epidemiological populations of interest in the COVID-19 pandemic (Susceptible [S], Infected [I], Recovered [R] and dead [D]), information that is often key to guiding decision-making in the fight against epidemics. In order to obtain a better model calibration and a lower prediction error in the short term, we performed the model segmentation in 6 stages of periods of 14 days each. At each stage, the epidemiological that define the system of equations are empirically estimated by linear regression of the epidemiological surveillance data that the Peruvian Ministry of Health collects and reports daily. This strategy showed better model calibration compared to an unsegmented SIR-D model.

El presente estudio trata sobre el desarrollo de un problema matematico (ecuaciones aplicadas a edades) dentro del area del algebra a nivel secundaria. Donde se anadio la concepcion de algunas formalidades matematicas como corresponde al nivel universitario que esta dentro de las exigencias a los estudiantes de primer ano de formacion (Estudios Generales). El problema aplicado a los estudiantes se enfoca en el analisis de la posible respuesta de acuerdo al enunciado de la misma, y generar un debate sobre el modelamiento matematico de un problema real expresado en ecuaciones matematicas.

The impact of research is increasingly gaining importance as science is understood as a means to solve the challenges of humanity. Therefore, processes of interaction between science and policy makers are needed, namely Science-Policy Interface (SPI). But who is actually participating in SPIs? This question is relevant since scientific findings can be subject to interpretation, might contradict each other or can be driven by normative frameworks. Additionally, complex challenges require the involvement of all relevant disciplines and if certain disciplines are not heard, policies might as well only address parts of the problem. To unpack respective processes, this paper explores the opportunities of bibliography to trace and track science-policy interactions applying it to the field of wildfire risk management (WFRM). An analysis of bibliometric data provided by Dimensions was carried out. Therefore, the development of the numbers of publications and policy documents over time as well as the numbers of publications and policy documents in different fields of research (FoR) are considered. Furthermore, the Altmetrics of publications which are cited in policy documents are compared to the total of publications with reference to WFRM. It can be stated that the number of publications with reference to WFRM follows the general trend of an increasing publication rate. Individual deviations from the general trend can be attributed to extraordinary wildfire events. The number of policy documents with reference to WFRM seems to correlate more strongly with the number of scientific publications with reference to WFRM than to the general trend in the number of policy documents. In addition, indicators for delay of 6 to 7 years in knowledge uptake from science to policy were found. Regarding the FoRs, three clusters of were identified. While two of these clusters indicate a positive correlation between the number of publications in a FoR and the number of citations, one cluster of FoR has low numbers of citations in policy documents while the number of publications is high. That leads to the conclusion, that there are bias respective unknown impact factors which affect whether or not a policy maker considers a particular FoR. One impact factor seems to be the attention a publication receives in scientific but also non-scientific communities. The Altmetric Scores of publications with citations in policy documents are double as high as the Altmetric Scores of the total of publications with reference to WFRM. By analysing the composition of the Altmetric Scores of cited publications respective the Altmetric Donuts, it could be found that the vast majority of publications that are cited in policy documents did receive attention in social media, especially twitter. Another result of the analysis is, that the data quality concerning the links between policy documents and publications is insufficient. However, the bias found in the SPI demonstrate the usefulness of this bibliometric approach. With increasing reliability of bibliometric databases, the methodology presented in this paper can be applied broadly as a tool to analyse SPIs and help to create transparency on the integration of scientific findings into policy processes.

This explorative study provides insights into how civil protection organizations can learn, be innovative, and develop their capabilities toward achieving greater organizational resilience. After the enormous impact of the COVID-19 pandemic, civil protection organizations had to actively shape crisis-related learning processes, particularly concerning workflows and organizational structures, collaboration with stakeholders, preparedness, risk analysis, digitalization, and the political framework. Empirical findings collected in Europe during and between the main pandemic peaks of 2020 and 2021 were analyzed for implications for policymakers and civil protection organizations. Key findings illustrate how important it is for civil protection organizations to respond quickly and adapt flexibly in times of crisis. In interviews with civil protection experts, respondents highlight the benefits of a partner network and the need for digital capabilities and data infrastructure. Other relevant factors in dealing with a crisis were found to be self-evaluation and the ability to recover from a previous wave while preparing for and responding to the next.

Einleitung: Die kongenitale Zwerchfellhernie stellt eine komplexe Fehlbildung dar, bei der es infolge der Herniation von Bauchorganen in den Brustkorb durch einen Defekt im Zwerchfell zur verminderten Lungenentwicklung kommt. Diese Unterentwicklung der fetalen Lunge wird Lungenhypoplasie genannt und führt zu einer erhöhten Mortalität und Morbidität nach der Geburt. Die pränatale Sonographie stellt die Diagnose und ermöglicht die Erstellung von verschiedenen antenatalen Prognoseparameter (z. B. LHR und Leberherniation) als Prädiktor für das fetale Outcome zur frühzeitigen Entschlussfindung bezüglich des weiteren Schwangerschaftsverlaufes sowie zur Planung des postnatalen Managements. Patienten und Methode: Retrospektiv wurden an einem Tertiärzentrum über einen Zeitraum von 15 Jahren Daten von 58 Feten mit isolierter Zwerchfellhernie hinsichtlich der antenatalen Prognoseparameter und dem fetalen Outcome untersucht und verglichen. Zu den ausgewerteten Daten zählen die jeweiligen Ultraschallbefunde der Feten sowie deren Dokumentation zum Schwangerschaftsausgang und dem postnatalen Verlauf. Ergebnisse: Das Gesamtüberleben der Feten mit isolierter Zwerchfellhernie lag bei 74.1 %. Feten mit einer LHR >1 hatten eine signifikant (p 45 % vs. o/e LHR ≤45 % oder einem QLI >0.6 vs. QLI ≤0.6 ermittelt. Zusammenfassung: Die vorliegende Arbeit bestätigt die prognostische Wertigkeit der Leberherniation und der LHR als wichtige Bestandteile der Prognosestellung bei Feten mit isolierter Zwerchfellhernie., Introduction: Congenital diaphragmatic hernia is a complex malformation in which the herniation of abdominal organs into the chest through a defect in the diaphragm can lead to reduced lung development. This underdevelopment of the fetal lungs is called pulmonary hypoplasia and results in increased mortality and morbidity after birth. Prenatal sonography provides the diagnosis and allows the formation of various antenatal prognostic parameters (e.g. LHR and liver herniation) as a predictor of fetal outcome to support early decision-making regarding the further course of the pregnancy as well as for the planning of the postnatal management. Patients and method: We evaluated retrospectively data from 58 fetuses with isolated diaphragmatic hernia with regard to antenatal sonographic prognostic parameters and fetal outcome at a tertiary center over a period of 15 years. The evaluated data include the respective ultrasound findings of the fetuses as well as the documentation on the outcome of pregnancy and the postnatal course. Results: The overall survival rate of the fetuses with isolated diaphragmatic hernia was 74.1%. Fetuses with an LHR >1 had a significantly (p 45% vs. o/e LHR ≤45% or a QLI >0.6 vs. QLI ≤0.6. Summary: Our study confirms the prognostic value of liver herniation and LHR as important components of the prognosis in fetuses with isolated diaphragmatic hernia.

In this work, we will prove the Cayley-Hamilton theorem using algebraic geometry. We will see a different proof than the one seen in a linear algebra course, in this case we will use the Zariski topology, then we will take advantage of the fact that every square matrix of order n _ n, with entries in a field K, denoted by (aij)n_n can be seen as an element of the affine space of dimension n _ n over the field K and thanks to this, we can resort to algebraic sets and algebraic varieties in order to obtain some results seen in an algebraic geometry and to get a proof of the Cayley-Hamilton theorem. En este trabajo, probaremos el teorema de Cayley-Hamilton utilizando geometría algebraica. Veremos una prueba diferente a la que se ve en un curso de álgebra lineal, en este caso utilizaremos la topología de Zariski, luego nos aprovecharemos de que toda matriz cuadrada de orden nxn, con entradas en un cuerpo K, denotada por (aij)nxn puede ser vista como un elemento del espacio afín de dimensión nxn sobre el cuerpo K y gracias a esto podemos recurrir a los conjuntos algebraicos y a las variedades algebraicas para así obtener algunos resultados vistos en un curso de geometría algebraica y conseguir una prueba del teorema de Cayley-Hamilton.

In the present work, a mathematical model is built that represents the dynamics that exist between phytoplankton (F), zooplankton (Z) and anchovy (A) from the model of Samares and Anal. This food chain occurs in the Peruvian maritime area where there is a three-link ecosystem, in addition to the fact that the food chain is a main axis in the ecological balance within the sea. The behavior of the populations (maritime species) will be studied where the stability of the model (Routh-Hurwitz criterion) in the long term will be determined, where it will be analyzed with the Dulac-Bendixon criterion to evaluate the existence of closed periodic orbits. And the respective computational simulations to complement the study and interpret the situations that affect the maritime ecosystem. En el presente trabajo, se construye un modelo matemático que representa la dinámica que existe entre el fitoplancton (F), el zooplancton (Z) y la anchoveta (A) a partir del modelo de Samares y Anal. Esta cadena alimenticia se presenta en el área marítima peruana donde se encuentra un ecosistema de tres eslabones, además que la cadena alimenticia es un eje principal en el equilibrio ecológico dentro del mar. Se estudiará el comportamiento de las poblaciones (especies marítimas) donde se determinará la estabilidad del modelo (criterio de Routh-Hurwitz) en el largo plazo, donde se analizará con el criterio de Dulac-Bendixon para evaluar la existencia de órbitas periódicas cerradas. Y las respectivas simulaciones computacionales para complementar el estudio e interpretar las situaciones que afectan al ecosistema marítimo.

Background: Planned improvements in semiconductor chip performance have historically driven improvements in lithography and this is expected to continue in the future. The International Roadmap for Devices and Systems roadmap helps the industry plan for the future. Aim: The 2021 lithography roadmap shows requirements, possible options, and challenges for the next 15 years. Results: Critical dimensions in logic chips are now small enough that stochastics, i.e., random variations in photon, molecules, and photoresist image forming processes, introduces random variations in sizes and stochastic-driven defects. As critical dimensions get smaller, stochastics becomes a bigger challenge. The roadmap projects that despite projected improvements in tools, photoresist, device design, and patterning processes, resist dose to print will still have to roughly triple over the next 10 years to maintain acceptable stochastics unless major process or chip design changes are made. This will raise patterning costs substantially. Other patterning options are under development but they also have challenges related to defects. Edge placement error (EPE) is also a challenge for future devices. Long-term, logic device requirements will drive stacked devices, and yield and process complexity will be key challenges. Conclusions: Logic devices will drive leading edge lithography. Improved extreme ultraviolet lithography is a leading candidate but other options are possible. Key short-term challenges are stochastics, EPE, and cost. Resist dose to print is expected to rise substantially as critical dimensions shrink unless substantial process innovation occurs. For the long term, the challenges will be yield and process complexity when logic devices switch to 3D scaling