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Several tool wear models for machining operations have been reported in the literature. However, most of them are capable of modeling only a part of the wear curve, designed for quasi-linear curves or need to be fitted by means of differential equations. In this research, a new analytical easy-to-use wear model is proposed, taking into consideration the geometry of the cutting insert and the influence of the cutting speed and the tool-workpiece contact stress. In addition, the effect of the critical machining time, relative to the tool degradation, has also been introduced. The wear model describes completely the wear curve, from the initial rapid wear stage to the thermal-activated wear rate acceleration. The constants and parameters of the equation are determined by cutting experiments from the cutting forces and flank wear registers under a variety of technological parameters. This model has been validated for turning process on Ti48Al2Cr2Nb aluminide with uncoated carbide tool under different cutting conditions, varying the cutting speed and the geometrical position of the tool. It has been demonstrated its suitability to predict tool life, according to a defined wear criterion.

Traditional lubrication systems are not environmentally sustainable, being necessary to find techniques less harmful to the environment that provide efficient machining processes to improve cutting conditions. In this paper, it is proposed a new and less polluting lubrication technique called Low Initial Lubrication condition, LIL. It involves applying a low quantity of oil on the workpiece and the rake face of the tool at the beginning of the machining process. This lubrication technique has been tested on cylindrical turning of cupronickel 70/30 alloy, which is widely used in marine and naval applications. Different empirical cutting models are proposed in order to predict cutting forces. Relevant parameters of machining processes, such as the specific cutting energy and shear cutting strength have been evaluated. In addition, FEM simulation with a simple material model is proposed for the prediction of the cutting force. The lubrication system herein researched permits to reduce the value of the cutting force significantly in comparison to dry and flood machining under some cutting conditions.

Objetivo: Presentar nuestra experiencia inicial en el desarrollo de la nefrectomía radical laparoscópica en el Centro Oncológico Estatal ISSEMyM en Toluca Estado de México Materiales y métodos: Estudio retrospectivo y descriptivo. Se evaluaron de manera retrospectiva todas las nefrectomías radicales laparoscópicas realizadas por diagnóstico de tumoración renal en el centro oncológico estatal ISSEMyM en un periodo de 5 años comprendido entre 2013-2018. Resultados y discusión: Se encontraron 58 pacientes a los que se les realizó nefrectomía laparoscópica durante el periodo de estudio. El tamaño tumoral fue de 1.5 a 12 cm, con un promedio de 5.77 cm. El porcentaje de conversión fue del 12.06%, de los cuales 4 fueron por hemorragia incontrolable en hilio renal. El tiempo promedio quirúrgico fue de 165.2 minutos por procedimiento. El sangrado transoperatorio promedio fue de 369.82 ml. Se tuvieron 4 complicaciones (6.89%), tres clasificadas como Clavien-Dindo II y una Clavien-Dindo III, posiblemente relacionadas al tamaño del tumor ya que en 3 de estos fue mayor de 7 cm. El promedio de días de estancia intrahospitalaria fue de 1.94 días con un rango de 1 a 7 días. Se presentó recurrencia en 3 pacientes (5.17%). Conclusiones: La nefrectomía radical laparoscópica es una excelente técnica para el control oncológico, teniendo las ventajas de la cirugía de mínima invasión. Comparando nuestra experiencia inicial desde 2013 hasta la fecha con la de otros hospitales a nivel nacional e internacional, nos encontramos con resultados trans y posquirúrgicos similares, por lo que se continuará ofreciendo este abordaje.

During 2020–2021, the COVID-19 pandemics exacerbated the use of digital communication tools for the general population as well as for migrant and diasporic communities. Due to social distancing requirements, church activities had to be suspended or restricted, therefore, local congregations and denominations had to incorporate social media as part of their regular worship channels in an unprecedented way. At the same time, these new spaces opened an opportunity for diasporas to reconnect with their churches back home, and to participate in digital worship projects. In this paper, we study the case of the digital worship collective Adorando en Casa (AeC), which was started at the onset of the pandemics, producing several crowdsourced original musical compositions, uploaded in popular social media sites, and distributed via messaging apps. We focus on the reasons for participation of Venezuelan musicians and singers from different regions in the country, and from the large diaspora of Venezuelan Evangelicals. Additionally, we analyze the characteristics, structure, and theology of some of the songs recorded, to show how the concept of a digital diasporic spiritual consciousness is powerfully expressed through worship music.

Titanium aluminides are one of the most promising materials in aeronautical and automotive applications. However, their low machinability makes the processing of these alloys quite difficult under sustainability conditions, specially without lubrication. The current study focuses on the turning process of the Ti48Al2Cr2Nb gamma titanium aluminide under dry conditions. As far as we are aware, dry cutting is the most sustainable feature, although it has not been traditionally applied on titanium aluminides due to the accelerated tool wear that the material promotes. The main novelty of this work consists of providing a simple solution for reducing the tool wear based on the inclination of the cutting insert, what is evaluated in terms of tool wear and tool life, cutting forces, cutting temperature, surface integrity of the machined part, as well as its microhardness and microstructural effects. The results shown here clearly point out a better performance of the machining process. This fact could be understood if we take into consideration that an increment of the clearance angle from 6.3° to 11.6° and 15° increases the tool life by five and six times, respectively, using efficient cutting speeds, whose values have increased by 50% with respect to the original cutting conditions. This improvement is explained according to the reduction in the cutting temperature and friction forces in the flank face of the tool. In addition, the use of uncoated carbide inserts may lead to a better behaviour than the coated ones, considering the results obtained for a PVD TiAlN + AlCr2O3 coated insert herein researched.

Heat-assisted single point incremental forming or HA-SPIF has a great potential for producing one-piece batches of hard-to-form materials such as Ti6Al4V alloy for medical and aeronautical applications. One of the limitations of the process is the difficulty in achieving a reasonable surface finish, which makes essential the characterization of the tribological process in the tool–sheet contact. In fact, not much work can be found at this point in literature. In this research, a novel procedure for evaluating the adhesion on the tool surface is proposed and the influence of the temperature is determined. The surface finish of parts is analyzed, and the changes promoted by HA-SPIF appearing in the morphology of the external surface layer are characterized by SEM.

RESUMENINTRODUCCIÓNLos ganglioneuromas son tumores muy poco frecuentes, de comportamiento benigno, que derivan de la cresta neural. Su diagnóstico es generalmente incidental y de presentación clínica silente. Se localizan con mayor frecuencia en el retroperitoneo y mediastino, rara vez presentandose en la glándula suprarrenal (1/1 000 000 en la población general). REPORTE DE CASO Masculino de 56 años de edad, asintomático, quien es referido a valoración por hematuria microscópica. Al realizar Tomografía contrastada se encuentra tumoración suprarrenal izquierda de 4 cm, homogénea, con atenuación 4 cm y retardo en el lavado tumoral, el tratamiento terapéutico y diagnóstico más adecuado, es la adrenalectomía laparoscópica.

Hitherto unreported 2,6-dipropargyl-1,3,5,7-tetramethyl BODIPYs can be efficiently prepared by a Nicholas reaction/decomplexation protocol from 1,3,5,7-tetramethyl BODIPYs. The title compounds, which improve the BODIPY photostability by retaining their inherent photophysical and photochemical properties, can be engaged in efficient copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) "click-type"reactions with azido derivatives to provide all-BODIPY-triads or conjugated BODIPYs., We gratefully acknowledge the Spanish Ministerio de Ciencia e Innovación for financial support (Project Nos. RTI2018- 094862-B-100, MAT2017-83856-C3-1-P and 3-P; PiD2020- 114755GB-C31 and -C33) and the Gobierno Vasco (GV) (Project No. IT912-16) for financial support. We are indebted to Ms. Marina Rodríguez (IQOG-CSIC) for skillful technical support. E.G.M.H. thanks GV for his predoctoral fellowship.

Titanium aluminide Ti48Al2Cr2Nb was tribologically tested on a pin-on-disk tribometer from −50 to 600 °C, using coated and uncoated carbide cutting tools as a pin. The goals were to characterise the wear and friction behaviour and to find the most efficient tool for turning processes. A transition from ploughing to plastic deformation and adhesive wear was observed as temperature raises. The friction coefficient reached the minimum value at 600 °C, mainly due to the lubricating effect of the TiO2-tribolayer formed. However, excessive tool wear occurs at this temperature due to the oxidised debris. The PVD TiAlN+AlCr2O3 coated tool behaved best. Although working under cryogenic condition is not effective regarding friction, a decline in the tool wear was observed.

Traditional flood lubrication in machining processes is considered an unsustainable technique. In this paper, the low initial lubrication (LIL) technique is analysed during turning of cupronickel 70/30 alloy, in terms of surface roughness. A tribological analysis has been developed on a pin-on-disk tribometer comparing different lubrication systems, obtaining comparative results of friction and tool wear. It has been found that the tool wear is 73% lower in comparison to flood lubrication. LIL technique shows the ability to reduce the friction coefficient compared to dry machining and leads to improve tool wear in comparison with flood lubrication. The surface integrity evaluation of machined parts finds that the LIL technique can improve the surface roughness under specific machining conditions.

Osasun esparruan, minbizia da gaixotasunen artean gizartearen kezka garrantzitsuenetarikoa bere heriotza-tasa altua dela eta. Arazo honi aurre egiteko ikerkuntzan ahalegin nabariak eta ugariak egiten ari dira minbizia sendatzeko eta metodo terapeutiko berriak bilatzeko, radioterapia eta kimioterapiaren albo-efektu kaltegarriak osasunean ekiditeko. Azken bolada honetan, terapia fotodinamikoak arrakasta izan du alternatiba osagarri bezala batez ere larruazaleko minbiziak tratatzeko. Metodo honetan argia da aktibatzailea, eta fotosentikortzaile bat behar da oxigeno singletea sortzeko. Izan ere azken espezie hau zitotoxikoa da eta aktibitate antikantzerigenoa erakusten du. Lan honetan arreta fotosentikortzaileetan jartzen da. Zehazki, hauen zenbait alderdi garrantzitsu azaldu eta aztertzen dira, hala nola haien diseinu molekularra, bete behar dituzten eskakizunak aipatuz, eta baita azaltzen dira argiak zuzendutatako oxigeno singletearen sorreraren atzean dauden prozesu fotofisikoak. Bukatzeko, adierazten dira gaur egun eskuragarri dauden fotosentikortzaile organikoak, bereziki BODIPY izeneko koloratzaileak azpimarratuz.; One of the most noticeable concerns in society related with health is cancer owing to its high mortality rate. A great deal of research is conducted to treat cancer, find novel therapeutic treatments, and to avoid the harmful side effects of radiotherapy and chemotherapy in health. Nowadays, photodynamic therapy has arisen as a successful complementary alternative, mainly for skin diseases induced by cancer. In this light-driven method, a photosensitizer is required to generate singlet oxygen. Indeed, this last cytotoxic moiety shows anticarcinogenic activity. The herein reported work is focused on photosensitizers. To this aim, we detail the molecular design to fulfill the required conditions, and explain the underlying photophysical phenomena behind the light-induced singlet oxygen generation. Finally, we report the state of the art regarding organic photosensitizers, with special interest in those based on BODIPY dyes.

Titanium is one of the most interesting materials in modern manufacturing thanks to its good mechanical properties and light weight. These features make it very attractive for use in the aeronautical and aerospace industries. Important alloys, such as Ti6Al4V, are extensively used. Nevertheless, titanium alloys present several problems in machining processes. Their machinability is poor, affected by low thermal conductivity, which generates very high cutting temperatures and thermal gradients in the cutting tool. Lubricants and cutting fluids have traditionally been used to solve this problem. However, this option is unsustainable as such lubricants represent a risk to the environment and to the health of the operator due to their different chemical components. Therefore, novel, sustainable and green lubrication techniques are necessary. Dry machining is the most sustainable option. Nevertheless, difficult-to-machine materials like titanium alloys cannot be machined under these conditions, leading to very high cutting temperatures and excessive tool wear. This study is intended to describe, analyse and review the non-traditional lubrication techniques developed in turning, drilling and milling processes since 2015, including minimum quantity of lubricant, cryogenic lubrication, minimum quantity of cooling lubrication or high-pressure coolant. The aim is to provide a general overview of the recent advances in each technique for the main machining processes.

ResumenLa hipertensión arterial es una de las afecciones más frecuentes en la población general y se estima que afecta aproximadamente al 26% de la población mundial. En los pacientes hipertensos existe una mayor morbimortalidad por accidentes cerebrovasculares, síndromes coronarios agudos e insuficiencia cardiaca. La producción excesiva de aldosterona por aldosteronismo primario es una forma de hipertensión que puede ser curada. La adrenalectomía laparoscópica es el estándar de oro para el abordaje de la glándula suprarrenal, disminuyendo la morbimortalidad de dicho procedimiento, por lo que se reporta que la recuperación de la HTA a cifras normales es en promedio de 6 meses en un 30 a 90% de los pacientes. Se presenta el caso clínico de una paciente con hiperaldosteronismo primario que se diagnosticó con niveles de renina y aldosterona, así como con tomografía simple y contrastada. Se encontró un adenoma hipersecretor y se realizó una adrenalectomía laparoscópica. El manejo interdisciplinario se recomienda para descartar múltiples afecciones que condicionan hipertensión arterial de origen suprarrenal, teniendo una importante eficacia en el tratamiento médico para posteriormente realizar la adrenalectomía laparoscópica.AbstractHigh blood pressure is one of the most frequent pathologies in the general population and is estimated to affect approximately 26% of the world population. Hypertensive patients have greater morbidity and mortality due to stroke, acute coronary syndromes, and heart failure. The excessive production of aldosterone caused by primary aldosteronism is one form of high blood pressure that can be cured. Laparoscopic adrenalectomy is the criterion standard for the approach to the adrenal gland, reducing the morbidity and mortality of that procedure. High blood pressure is reported to reach normal figures at an average of 6 months in 30-90% of the patients. Presented herein is the case of a female patient with primary aldosteronism. Diagnosis was made by determining renin and aldosterone levels and through tomography studies with and without contrast. A hyper-secreting adenoma was found and laparoscopic adrenalectomy was performed. Interdisciplinary management is recommended for ruling out multiple pathologies that condition high blood pressure of adrenal gland origin. Such management leads to efficacious medical treatment and laparoscopic adrenalectomy can then be performed.

El autor expone la importancia de repensar el servicio público bajo la óptica de la ética, particularmente en un contexto donde la eficiencia, la eficacia y la economía han mostrado sus límites en la construcción de una relación de confianza entre gobierno y ciudadanía. Asimismo, argumenta sobre la necesidad de incorporar y fortalecer los valores que propone la ética pública a la legislación mexicana para que tanto la autoridad como la sociedad vigilen la actuación virtuosa de las instituciones.

El presente ensayo busca explicar y esclarecer el por qué el actual Gobierno Federal se vio en la necesidad de promover un consenso nacional entre diversos actores relevantes en la toma de decisiones en México, el cual se presentó a la opinión pública como el Pacto por México. Asimismo, se hace una enumeración de los acuerdos más importantes incluidos en este ejercicio para entonces, analizar estas acciones con el concepto del Nuevo Institucionalismo. México vive una etapa de cambios acelerados con motivo del reciente relevo del gobierno federal, ya que tras 12 años de gobiernos emanados del Partido Acción Nacional la ciudadanía optó en la última opción, por el Partido Revolucionario Institucional.