LQR-Based adaptive virtual inertia for grid integration of wind energy conversion system based on synchronverter model

This paper proposes adaptive virtual inertia for the synchronverter model implemented in a wind turbine generator system integrated into the grid through a back-to-back converter. A linear dynamic system is developed for the proposed adaptive virtual inertia, which employs the frequency deviation and the rotor angle deviation of the synchronverter model as the state variables and the virtual inertia and frequency droop gain as the control variables. In addition, the proposed adaptive virtual inertia uses a linear quadratic regulator to ensure the optimal balance between fast frequency response and wind turbine generator system stress during disturbances. Hence, it minimizes frequency deviations with minimum effort. Several case simulations are proposed and carried out in MATLAB/Simulink software, and the results demonstrate the effectiveness and feasibility of the proposed adaptive virtual inertia synchronverter based on a linear quadratic regulator. The maximum and minimum frequency, the rate change of the frequency, and the integral of time-weighted absolute error are computed to quantify the performance of the proposed adaptive virtual inertia. These indexes are reduced by 46.61%, 52.67%, 79.41%, and 34.66%, in the worst case, when the proposed adaptive model is compared to the conventional synchronverter model

Antp transcriptional activity is modulated by the formation of the trimeric Antp-TBP complexes with TFIIEβ, Exd and BIP2

Homeoproteins are transcriptional factors that bind to DNA through a highly conserved binding domain known as the homeodomain (HD) which recognizes short regions rich in AT to control the development of the body appendages of organisms. However, their structural and recognition similarities make it difficult to explain how homeoproteins are capable of carrying out their function. Previous results have shown that Antp homeoprotein can establish dimeric interactions with TBP, TFIIEβ, Exd, BIP2 and more recently through BiFC-FRET we confirmed that Antp and TBP can form trimeric complexes with TFIIEβ/Exd/BIP2. Therefore, is important to show how these trimeric complexes modulate Antp transcriptional activity. The experimental approach selected for this project was to perform in vitro transactivation assays in HEK-293 cells transfected with the combinations of Antp and TBP-producing plasmids with TFIIEβ / Exd / BIP2 plasmids using a Luciferase reporter plasmid. Our results show that trimeric interaction of Antp-TBP-TFIIEβ induced a significant increase of 138% in the Antp transcriptional activity. By contrast, trimeric complexes of Antp-TBP-Exd and Antp-TBP-BIP2 modified the transactivating capacity of Antp, decreasing transcription by 20 and 26% respectively. According to this, we were able to confirm that the trimeric complexes Antp-TBP/TFIIEβ/Exd/BIP2 are involved in the modulation of Antp transcriptional activity. So, now it is interesting to analyze how these trimeric complexes are involved in the activation and/or repression of target genes of Antp during genetic control of development in Drosophila melanogaster

Seguimiento de la productividad en obra: técnicas de medición de rendimientos de mano de obra

Management systems often present few, since those systems don't adopt control indexes like productivity, which prevents form identifying and defining (from both the systematic and systemic point of view) the problems that require taking corrective and mitigating actions [1]. Methodologies such as "Lean Construction" are based on the management of processes, to maximize revenues and minimize costs, here the improvement of productivity becomes an important parameter for the management system; focusing on the verification of both the process and the product, leaving behind the typical tendency of verifying only results, that is the tendency for control techniques [2]. This study pretends to identify the controlling techniques that should be used when referring to productivity as the quality management control index.En todo sistema de gestión, la planeación sirve como marco de referencia a los programas de control. Adoptar buenas metodologías de seguimiento que acompañen a los procesos de planeación, con miras a lograr un buen desempeño en la gestión y alcanzar las metas deseadas, es una necesidad latente. Aunque en las nuevas metodologías de gestión se hace ya explícita esta necesidad, es muy frecuente encontrar dificultades en los procesos de seguimiento de obra, al no emplearse indicadores adecuados que identifiquen, sistemática y sistémicamente, situaciones importantes que requieran corrección y/o mitigación [1]. La mayoría de las metodologías modernas de mejoramiento basan su estrategia buscando maximizar valor y minimizar pérdidas, razón por la cual, la productividad es uno de los indicadores importantes que mide el desempeño de una buena gestión. Este enfoque, es un planteamiento estratégico orientado hacia los procesos, donde prevalece la verificación y el aseguramiento del procedimiento y el resultado, más allá del viejo esquema de solo verificar resultados [2]. El presente trabajo apunta hacia metodologías de seguimiento, que definan a la productividad, como un indicador significativo de gestión y control en las obras de construcción, en especial la productividad de las cuadrillas de trabajo.&nbsp

Seguimiento de la productividad en obra: técnicas de medición de rendimientos de mano de obra

Management systems often present few, since those systems don't adopt control indexes like productivity, which prevents form identifying and defining (from both the systematic and systemic point of view) the problems that require taking corrective and mitigating actions [1]. Methodologies such as "Lean Construction" are based on the management of processes, to maximize revenues and minimize costs, here the improvement of productivity becomes an important parameter for the management system; focusing on the verification of both the process and the product, leaving behind the typical tendency of verifying only results, that is the tendency for control techniques [2]. This study pretends to identify the controlling techniques that should be used when referring to productivity as the quality management control index.En todo sistema de gestión, la planeación sirve como marco de referencia a los programas de control. Adoptar buenas metodologías de seguimiento que acompañen a los procesos de planeación, con miras a lograr un buen desempeño en la gestión y alcanzar las metas deseadas, es una necesidad latente. Aunque en las nuevas metodologías de gestión se hace ya explícita esta necesidad, es muy frecuente encontrar dificultades en los procesos de seguimiento de obra, al no emplearse indicadores adecuados que identifiquen, sistemática y sistémicamente, situaciones importantes que requieran corrección y/o mitigación [1]. La mayoría de las metodologías modernas de mejoramiento basan su estrategia buscando maximizar valor y minimizar pérdidas, razón por la cual, la productividad es uno de los indicadores importantes que mide el desempeño de una buena gestión. Este enfoque, es un planteamiento estratégico orientado hacia los procesos, donde prevalece la verificación y el aseguramiento del procedimiento y el resultado, más allá del viejo esquema de solo verificar resultados [2]. El presente trabajo apunta hacia metodologías de seguimiento, que definan a la productividad, como un indicador significativo de gestión y control en las obras de construcción, en especial la productividad de las cuadrillas de trabajo.&nbsp

Incidence of complications in breast reconstruction with autologous tissue in a third level hospital

Background: The objective of this study is to analyze the incidence of complications after breast reconstruction with pedicled or free flaps at the hospital general de Mexico "Dr. Eduardo Liceaga”. Methods: A retrospective, single-center study, including 44 female patients, who underwent immediate or delayed breast reconstruction after breast cancer, between 2019 and 2020, and had at least a 2-year follow up, evaluating the association between patient risk factors (age, history of radiotherapy, presence of overweight or obesity and immediate or delayed reconstruction) with the presence of complications such as seroma, hematoma, wound infection or wound dehiscence. We analyzed data with SPSS software, v23.0. Results: There was no statistically significant difference for the presence of complications associated with risk factors studied. Conclusions: We need more prospective, multicenter studies, including larger sample and strict follow up of patients

Trimeric Antp-TBP complexes with TFIIEβ and Exd modulated the transcriptional activity of Antp

Homeoproteins are transcription factors that bind to DNA through a highly conserved binding domain known as the homeodomain (HD), which recognizes short regions rich in A-T. This DNA binding triggers the modulation of multiple target genes responsible for identity in various structures along the A-P axis of D. melanogaster. However, the high similarity of homeodomains and their affinity for widely distributed sites in the genome poses the Hox paradox, which seeks to explain how homeoproteins acquire functional specificity so precisely. Previous evidence shows that homeoproteins like Antennapedia (Antp) form dimers with cofactors and other transcription factors to modulate their activity and also can form trimeric complexes with TBP/TFIIEβ/Exd. For this reason, we have conducted transactivation analyses to determine the effect of Antp-TBP-TFIIEβ and Antp-TBP-Exd complexes on Antp\u27s transcriptional activity. The experimental strategy involved transfecting HEK-293 cells with different combinations of plasmids producing Antp, TBP, TFIIEβ, and Exd, along with two reporter plasmids: a luciferase reporter with 5 binding sites for Antp and the sequence of a D. melanogaster basal promoter, and a β-galactosidase reporter. Our results reveal that the trimeric interaction of Antp-TBP-TFIIEβ induces a highly significant increase of 173% in Antp transcriptional activity. On the other hand, Antp-TBP-Exd trimer shows opposite results by decreasing Antp transcriptional activity until 61%. These findings suggest that the trimeric complexes Antp-TBP/TFIIEβ/Exd play a role in modulating Antp\u27s transcriptional activity, raising new questions about the in vivo effects of these complexes on Antp interactome and target genes

Caracterización de vacas de cuatro razas criollas colombianas por cinco proteínas séricas sanguíneas.

Colombia posee 7 razas bovinas criollas o descendientes directas de los ganados traídos por los españoles. El valor del criollo radica en su adaptación al trópico y en el extraordinario vigor híbrido que produce en cruzamiento con Cebú, el ganado más abundante en el país. Infortunadamente para Colombia las poblaciones criollas son reducidas, por lo cual es necesario adelantar programas racionales para su multiplicación y selección. Para realizar esta labor es indispensable conocer el grado de relación genética que estas razas tienen en la actualidad, lo cual se puede lograr mediante estudios de sus proteínas sanguíneas. Este tipo de investigación es muy escaso para razas criollas adaptadas a condiciones tropicales. Los objetivos del presente estudio fueron comparar la composición protéica del suero sanguíneo de hembras de las razas Romosinuano, Blanco Orejinegro, Sanmartinero y Costeño con Cuernos, y estudiar el efecto de algunos factores no genéticos tales como edad y sexo, sobre dicha composición. Se utilizó electroforesis en papel y los datos fueron analizados por el método de cuadrados mínimos. De acuerdo con el número de diferencias significativas en las 5 proteínas estudiadas, las razas con mayor similitud en composición de proteínas séricas son el Romosinuano y el Blanco Orejinegro y las más disímiles, el Blanco Orejinegro y el Sanmartinero. Además, parece que la Sanmartinera es la más divergente de las razas criollas estudiadas. Para la globulina alfa 1, los efectos de edad (P menor que 0.05) y sexo (P menor que 0.01) fueron significativosGanado de leche-Ganadería lech

Comparación de la percepción social en playas recreativas arenosas de dos bahías localizadas en el Pacífico Mexicano

En el presente trabajo se desarrollaron dos formatos de encuesta, para incorporar la percepción de los usuarios a la evaluación de la calidad de las playas (Cervantes, 2006 y Silva-Iñiguez, 2006); ambos basados en un modelo cuantitativo para revelar la percepción social de las playas localizadas en la bahía de Santiago, Manzanillo, Col (MZO) y en Acapulco, Gro (ACA). Se aplicaron un total de 790 encuestas (ACA: 390 y MZO: 400), que permitieron conocer el perfil de los usuarios, sus hábitos de recreación y sus opiniones sobre las condiciones biofísicas y de infraestructura de cada playa. En ambas playas la mayoría prefirieron asistir acompañados por sus familias; las principales actividades recreativas fueron nadar, descansar, comer y beber. En general las demandas en ambos sitios coincidieron con incrementar el número de botes de basura, la frecuencia en el servicio de recolección y limpieza, baños y regaderas. Las razones por la que los usuarios seleccionaron la playa a visitar fueron la seguridad y vigilancia, así como las características biofísicas de la misma. La incorporación de esta información a modelos y/o esquemas de evaluación y gestión de playa (a través de índices ambientales) permitió realizar la valoración integral de la playa.In this paper it was developed two survey formats, to include the perception of users on the assessment of the quality of the beaches (Cervantes, 2006 and Silva-Iñiguez, 2006), both based on a quantitative model to reveal the social perception of the beaches on Santiago Bay, Manzanillo, Col (MZO) and Acapulco, Guerrero (ACA). We did a total of 790 surveys (ACA: 390 and MZO: 400), which allowed the user profile, recreation habits and their views on the biophysical and infrastructure of each beach. In both beaches, most people, attended with their families, the main recreational activities were swimming, resting, eating and drinking. In general the demands on both sites agreed to increase the number of waste baskets, the frequency of collection service and cleaning bathrooms and showers. The reasons why the users selected to visit the beach were the safety and security, as well as the biophysical characteristics of the same. Incorporating this information to models and / or evaluation schemes and beach management (through environmental ratings) allowed the comprehensive assessment of the beach

Descriptive analysis of histological types in women undergoing post mastectomy breast reconstruction

Background: Breast cancer is a pathological entity that widely compromises the life and quality of life of affected women; in addition to the great affectation to the current health services. Therefore, maintaining an accurate and complete cancer registry program is one of the most important factors in implementing national cancer control programs and evaluating the results of screening, diagnosis, and treatment. Among the current limitations in the studies, there is a gap in the study of the population undergoing breast reconstruction. Methods: A retrospective study was carried out at hospital general de México “Dr. Eduardo Licéaga” with the information from the clinical records of the period 2019-2020. Patients undergoing breast reconstruction after mastectomy with histological report were included. Through non-probabilistic sampling, a population of 138 women was formed. For data analysis, frequencies and percentages were calculated for the qualitative variables; while for the quantitative variables, mean and standard deviation were calculated. Results: 138 women who underwent breast reconstruction were included, the mean age was 49.9±10.85 years, the mean BMI was 26.80±4.62 kg/m2, the secondary educational level predominated (34.8%), radiotherapy was applied to 34.1%, reconstruction was late in 75.4%, the most frequent reconstruction technique was TRAM flap (44.2%), the histological type of invasive ductal carcinoma predominated (68.1%). Conclusions: In women undergoing post-mastectomy breast reconstruction, the histological type of invasive ductal carcinoma predominates.

Ancestry as a potential modifier of gene expression in breast tumors from Colombian women

Background Hispanic/Latino populations are a genetically admixed and heterogeneous group, with variable fractions of European, Indigenous American and African ancestries. The molecular profile of breast cancer has been widely described in non-Hispanic Whites but equivalent knowledge is lacking in Hispanic/Latinas. We have previously reported that the most prevalent breast cancer intrinsic subtype in Colombian women was Luminal B as defined by St. Gallen 2013 criteria. In this study we explored ancestry-associated differences in molecular profiles of Luminal B tumors among these highly admixed women. Methods We performed whole-transcriptome RNA-seq analysis in 42 Luminal tumors (21 Luminal A and 21 Luminal B) from Colombian women. Genetic ancestry was estimated from a panel of 80 ancestry-informative markers (AIM). We categorized patients according to Luminal subtype and to the proportion of European and Indigenous American ancestry and performed differential expression analysis comparing Luminal B against Luminal A tumors according to the assigned ancestry groups. Results We found 5 genes potentially modulated by genetic ancestry: ERBB2 (log2FC = 2.367, padj<0.01), GRB7 (log2FC = 2.327, padj<0.01), GSDMB (log2FC = 1.723, padj<0.01, MIEN1 (log2FC = 2.195, padj<0.01 and ONECUT2 (log2FC = 2.204, padj<0.01). In the replication set we found a statistical significant association between ERBB2 expression with Indigenous American ancestry (p = 0.02, B = 3.11). This association was not biased by the distribution of HER2+ tumors among the groups analyzed. Conclusions Our results suggest that genetic ancestry in Hispanic/Latina women might modify ERBB2 gene expression in Luminal tumors. Further analyses are needed to confirm these findings and explore their prognostic value.PLoS Journal