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This article aims to study the simulation and design of automobile automatic clutch under mechatronics. A new control strategy for the automatic clutch of the electromagnetic transmission is proposed. The clutch mechanism model, clutch drive model, clutch system model, and internal combustion engine model are constructed. The fuzzy logic control performance of the automatic clutch was verified in different operating modes, including starting on flat roads and mountain roads. The method provides a reasonable reference for the design of an automatic clutch of electromagnetic continuously variable transmission.

To study the radiation effect of Fermi–Dirac (F–D) semiconductor devices based on numerical simulation, two methods are used. One is based on the combination of F–D statistical method and computer simulation. The method discusses the influence of temperature and light energy on the carrier number by starting from an intrinsic silicon semiconductor and carries out computer simulation on the carrier number in intrinsic silicon semiconductor. TID Sim, a three-dimensional parallel solver for ionizing radiation effects of semiconductor devices, is developed. The ionization radiation damage of typical metal oxide semiconductor (MOS) FET NMOS and bipolar transistor GLPNP is simulated. It was proved that the variation trend was close to a straight line in the temperature range (278–358 K) studied in this article. The results are consistent with those of the statistical distribution of semiconductor carriers. This method is suitable for calculating the number of semiconductor carriers, and it is an effective method to study the problems related to carrier distribution.

En el presente artículo se analiza el capital social como factor de emprendimiento en los países de la OCDE. Se utilizan las bases de datos del Global Entrepreneurship Monitor (GEM) y la World Values Survey (WVS). De la primera se obtiene la variable de emprendimiento y de la segunda se obtienen variables de capital social, como la confianza y la pertenencia a un grupo del tejido social. Se utiliza un modelo de panel con efectos aleatorios. Los resultados sugieren que las variables de capital social impactan positivamente en la actividad de emprendimiento, incrementando su probabilidad de éxito, no solo en la fase inicial sino también en el largo plazo. || In the present article, social capital is analyzed as entrepreneurship factor across OECD countries. The databases of Global Entrepreneurship Monitor (GEM) and the World Values Survey (WVS) are used. Entrepreneurship variable is obtained from GEM, and social capital variables are obtained from WVS. Confidence and to belong a social group are considerate as social capital variables. A panel model with random effects is used. The results suggest that social capital variables have a positive impact on entrepreneurial activity, increasing their probability of success, not only in the initial phase but also in the long term.

In this work, we deal with the predecessors existence problems in sequential dynamical systems over directed graphs. The results given in this paper extend those existing for such systems over undirected graphs. In particular, we solve the problems on the existence, uniqueness and coexistence of predecessors of any given state vector, characterizing the Garden-of-Eden states at the same time. We are also able to provide a bound for the number of predecessors and Garden-of-Eden state vectors of any of these systems.

O artigo analisa os Parâmetros Curriculares Nacionais (PCNs) para o terceiro e quarto ciclos do ensino fundamental a partir de uma dupla perspectiva. Explicita como a questão curricular se colocou internamente ao plano político-institucional, enfatizando as relações que se estabeleceram entre o Conselho Nacional de Educação (CNE) e o Ministério da Educação e do Desporto (MEC) em torno da proposta dos PCNs e da definição de diretrizes curriculares para o ensino fundamental. Também coteja as proposições mais gerais das Diretrizes Curriculares Nacionais e dos PCNs, visando a oferecer elementos para a compreensão das nuanças políticas implicadas nas duas elaborações curriculares. Como conseqüências destas análises, o texto explicita a mútua omissão que caracterizou as relações entre o MEC e o CNE.

Residues of crisantemos, clavel, statice and kikuyo grass alone or with cow dug and mixture of all they, were composted with aid of earthworm Eisenia fetida. These lombricomposts were tested versus soluble fertilization in the crisantemo crop. The best chemical and biological quality of the lombricomposts from flower residue were obtained with the admendment of cow dug, The bether yields and quality of crisantemo flower were obtained with lombricompost origined in flower residues with cow dug. The soluble fertilization was superior over the lombricomposts.Se hicieron lombricompuestos a partir de residuos de crisantemo, clavel, statice y kikuyo solos y con boñiga y una mezcla de tocios, con la lombriz Eisenia fetida. Tales lombricompuestos fueron comparados con el sistema de fetilización con solubles en el cultivo de crisantemos. La mejor calidad química y biológica de los lombricompuestos de los residuos de flores se logra con la adición de boñiga. Los mejores rendimientos y calidad de crisantemos se obtuvieron con los lombricompuestos de residuos de flores con boñiga, pero la fertilización con solubles fue superior a todos los lombricompuestos.

Objective: Noninvasive ventilation (NIV) failure it has been associated to worst clinical outcomes due to a delay in intubation and initiation of invasive mechanical ventilation (IMV). There is a lack of evidence in pediatric patients regarding this topic. The objective was to deter-mine the association between duration of IMV and length of stay, with duration of NIV prior tointubation/IMV in pediatric patients., Design: A prospective cohort study since January 2015 to October 2019., Setting: A pediatric intensive care unit., Patients: Children under 15 years with acute respiratory failure who failed to noninvasive ventilation., Interventions: None., Main Variables of Interest: Demographic variables, pediatric index of mortality (PIM2), pediatric acute respiratory distress syndrome (PARDS) diagnosis, IMV and NIV duration, PICU LOS were registered and intrahospital mortality., Results: A total of 109 patients with a median (IQR) age of 7 (3-14) months were included. The main diagnosis was pneumonia (89.9%). PARDS was diagnosed in 37.6% of the sample. No association was found between NIV duration and duration of IMV after Kaplan-Meier analysis (Log rank P = .479). There was no significant difference between PICU LOS (P = .253) or hospital LOS (P = 0.669), when categorized by NIV duration before intubation. PARDS diagnosis was associated to an increased length of invasive ventilation (HR: 0.64 [95% IC: 0.42-0.99])., Conclusions: No association was found between NIV duration prior to intubation and duration of invasive ventilation in critical pediatric patients with acute respiratory failure., (Copyright © 2021 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.)

Wildfires affect different physical, chemical, and hydraulic soil properties, and the magnitude of their effects varies depending on intrinsic soil properties and wildfire characteristics. As a result of climate change, the frequency and intensity of wildfires have increased, and understanding their impact and predicting the temperature to which soils were exposed in previous events is becoming increasingly critical. Hence, the objectives of this study were to develop a soil-heating laboratory procedure to (a) identify changes in soil properties at different temperatures and (b) to infer the temperature ranges to which heated soils have been exposed. Saturated (K s ) and unsaturated (K u ) hydraulic conductivity, pH, electrical conductivity (EC), wet aggregate stability (WAS), soil water repellency index (RI m ), and soil organic matter content (SOM) were measured in six laboratory heated (LH) soils at 300, 500, 700, and 900 °C for 2 h. Bulk density (BD) and soil texture were measured in unheated (UH) and wildfire-unheated (WH) samples. UH samples were used as baselines to quantify changes in soil properties, and WH and LH samples were compared to determine the temperatures to which WH soils were exposed. The results show that in the studied temperature range, WAS exhibited a U-shaped trend, opposite to that of pH and EC. Ks and Ku (negative tension of -3 cm) tend to increase with temperature, reaching a maximum of 1.27·10-4 and 5.62·10-5 (m/s) at 900 °C, respectively. RIm was highly dependent on texture; loam soils had an average minimum and maximum of 1.84 and 2.73, at 900 and 300 °C, respectively, while sandy loam soils had an average minimum and maximum of 1.29 and 2.08 at 300 and 900 °C, respectively. Finally, the parameters that provided laboratory variation and a temperature range consistent with the results observed in naturally heated soils were WAS, RI m , pH, and EC., Competing Interests: Declaration of competing interest 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., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: In high-volume trauma centers, especially in developing countries, penetrating cardiac box injuries are frequent. Although many aspects of penetrating chest injuries have been well established, video-assisted thoracoscopy is still finding its place in cardiac box trauma and algorithmic approaches are still lacking. The purpose of this manuscript is to provide a streamlined recommendation for penetrating cardiac box injury in stable patients., Methods: Literature review was carried out using PubMed/ MEDLINE and Google Scholar databases to identify articles describing the characteristics and concepts of penetrating cardiac box trauma, including the characteristics of tamponade, cardiac ultrasound, indications and techniques of pericardial windows and, especially, the role of video-assisted thoracoscopy in stable patients., Results: Penetrating cardiac box injuries, whether by stab or gunshot wounds, require rapid surgical consultation. Unstable patients require immediate open surgery, however, determining which stable patients should be taken to thoracoscopic surgery is still controversial. Here, the classification of penetrating cardiac box injury used in Colombia is detailed, as well as the algorithmic approach to these types of trauma., Conclusion: Although open surgery is mandatory in unstable patients with penetrating cardiac box injuries, a more conservative and minimally invasive approach may be undertaken in stable patients. As rapid decision-making is critical in the trauma bay, surgeons working in high-volume trauma centers should expose themselves to thoracoscopy and always consider this possibility in the setting of penetrating cardiac box injuries in stable patients, always in the context of an experienced trauma team.

In Colombia, the number of younger female surgeons is increasing along with a growing interest in thoracic and cardiac surgery. It is our duty to motivate young female surgeons in pursuing a career in chest surgery to answer the already growing deficit of cardio-thoracic surgeons., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Congenital lobar overinflation is characterized by disruption of bronchopulmonary development which produces lobar or segmental bronchial abnormalities and overinflation of normal lung tissue. This is a 44-year old man, never smoker, who presents dyspnea every time he arrived in highlands, marked decreased breathing sounds and hyperresonance in the left hemithorax. Imaging studies suggested left upper lobe overinflation. The affected area was resected resulting in symptoms improvement. Accepted treatment is resection, however conservative management has been proposed for asymptomatic patients because cases of spontaneous improvement have been described. We recommend close monitoring and resection if symptoms or overinflation progress.

A pathogen such as C. albicans needs an efficient mechanism of iron uptake in an iron-restricted environment such as is the human body. A ferric-reductase activity regulated by iron and copper, and analogous to that in S. cerevisiae, has been described in C. albicans. We have developed an in-plate protocol for the isolation of clones that complement an aft1 mutation in S. cerevisiae that makes cells dependent on iron for growth. After transformation of S. cerevisiae aft1 with a C. albicans library, we have selected clones that grow in conditions of iron deficiency and share an identical plasmid, pIRO1, with a 4500 bp insert containing the URA3 gene and an ORF (IRO1) responsible for the suppression of the iron dependency. IRO1 does not show homology with AFT1 or with other sequences in the databases. Northern analysis demonstrates constitutive expression of IRO1. CAI4, a C. albicans strain isolated as Deltaura3, also has a deletion of the 3' half of IRO1, and displays in YNB medium similar phenotypic characteristics to S. cerevisiae aft1 mutant strains. Therefore, we consider IRO1 as a gene of C. albicans involved in the utilization of iron. However, in extreme conditions of iron deprivation, CAI4 seems to activate alternative mechanisms of iron uptake that allow a better growth than the wild strain SC5314. Analysis of its predicted protein sequence is in agreement with a role of Iro1p as a transcription factor., (Copyright 2000 John Wiley & Sons, Ltd.)