Implementación de un plan de mantenimiento preventivo para mejorar la disponibilidad mecánica de los tornos CNC de la empresa PROECSER SAC

En el presente estudio realizado se tuvo como problema las fallas continuas en el torno CNC del taller de la empresa PROECSER SAC, esta tesis tiene como prioridad aumentar la disponibilidad mecánica del torno CNC. Nuestra justificación parte de las entregas tardías de piezas mecánicas debido a fallas- mecánicas del torno CNC. el objetivo del estudio es la implementación de un plan de mantenimiento preventivo. La presente tesis es del tipo pre experimental, se trabaja en base de la metodología del tipo aplicada y de diseño pre experimental simple. Después de la implementación del plan de mantenimiento preventivo se tuvo como resultado un aumento en la disponibilidad mecánica en el año 2023 de 93.75% logrando un incremento del 10.82% en comparación del año 2022. Según Alonso Elías Pirela (2009), nos indica que la elaboración del plan de mantenimiento para los tornos, sirve para mejorar el funcionamiento, así como prevenir las fallas antes de que ocurran, también ayudan al aumento de la productividad y eficiencia del torno. Como conclusión se llegó que gracias a una vez implementado el plan de mantenimiento preventivo se redujeron las fallas, el personal tiene un mejor cuidado del equipo y ya no se ejecutan mantenimientos correctivos todos los días debido a la disminución de las fallas en el año 2023

Nivel de comprensión lectora en educandos de 4° de secundaria de una I.E. de Trujillo, 2024

La presente investigación aportó al Objetivo de desarrollo sostenible (ODS). Garantizar una educación inclusiva, equitativa y de calidad y promover oportunidades de aprendizaje durante toda la vida para todos. Tuvo como objetivo general conocer los niveles de comprensión lectora en educandos del 4° de secundaria de una I.E. Trujillo, 2024. La metodología que se utilizó fue de tipo básica, con enfoque cuantitativo y el diseño no experimental de carácter descriptivo. la información se recolectó a través de una evaluación de comprensión lectora y se utilizó como instrumento una lista de cotejo con 20 criterios de evaluación en tres dimensiones y fue validado por juicio de expertos, además se obtuvo una confiabilidad de 0.796 a través de Alfa de Cronbach, la que se aplicó a una muestra de 120 educandos, seleccionados por muestreo no probabilístico. Los resultados determinaron que el 62,5 % se encuentra en el nivel logrado de la dimensión literal, el 54,2 % en nivel proceso en la dimensión inferencial y para la dimensión crítica el 45 % se encuentra en proceso de la comprensión lectora. Por lo que se concluye que la mayor parte de los estudiantes se encuentran en el nivel proceso de la comprensión lectora

Aplicación de las herramientas del Lean Manufacturing para mejorar la gestión de almacenes de la empresa TFM SAC

La investigación tuvo como objetivo general aplicar las herramientas del Lean Manufacturing para mejorar la gestión de almacenes en TFM SAC. La metodología utilizada fue de tipo aplicado, enfoque cuantitativo, y diseño pre experimental. En los resultados se determinó que las principales que generan una mala gestión de almacenes son la metodología logística no establecida; no realizan los pedidos a tiempo; desorden en diversas áreas; no registran las ingresos y salidas de los insumos y falta de capacitaciones; se determinó que la eficiencia en recepción de pedidos, days on hand y picking de manera inicial salió 0.55 unidades / hora hombre, 11.1% y 6.3% respectivamente; para ello, se estableció un procedimiento logístico desde la orden de pedido hasta la entrega del cliente interno, se desarrolló una evaluación a los proveedores y se pronosticó las compras de materiales, se aplicó la metodología 5S, se realizaron capacitaciones al personal operativo y se diseñó un sistema de inventario kardex. Como conclusión se tuvo que la dimensión eficiencia en recepción de pedidos aumentó en 0.63 unidades / hora hombre; la dimensión days on hand redujo un 8.1% y la dimensión picking redujo un 4.3%, validando de esta manera la hipótesis alterna de la investigación

Performance and Operation of the CMS Electromagnetic Calorimeter

The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

Impact of the COVID-19 Pandemic on the Perceived Quality of Palliative Care in Nursing Homes

The Nursing Homes End-of-life Programme (NUHELP) was developed in 2017 and is based on quality standards of palliative care, but it was not implemented due to the outbreak of the COVID-19 pandemic. Objectives: To describe perceptions among staff at nursing homes and primary health care (PHC) centres regarding the relevance, feasibility, and degree of achievement of quality standards for palliative care in nursing homes and to determine the differences in these perceptions before and after the pandemic. Methodology: Cross-sectional descriptive study. Professionals at eight nursing homes and related PHC centres who participated in NUHELP development assessed 42 palliative care standards at two time points (2018 and 2022). The Mann–Whitney U test was applied to analyse differences in the scores between these two times and between perceptions at nursing homes and at PHC centres. Results: The study population consisted of 58 professionals in 2018 and 50 in 2022. The standard regarding communication with persons affected by the death of a family member was considered less relevant (p = 0.05), and that concerning the culturally sensitive and dignified treatment of the body was less fully achieved (p = 0.03) in 2022 than in 2018. Social support (p = 0.04), sharing information among the care team (p = 0.04), patient participation (p = 0.04) and information about the treatment provided (p = 0.03) were all more poorly achieved in 2022 than in 2018. The perceptions of nursing home and PHC workers differed in several respects. Conclusions: Professional intercommunication and social support should be reinforced, and residents should be more actively involved in decision-making.Consejeria de Salud y Familias, Junta de Andalucia (Fundacion Publica Andaluza Progreso y Salud) AP-0105-201

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Performance of CMS hadron calorimeter timing and synchronization using test beam, cosmic ray, and LHC beam data

This paper discusses the design and performance of the time measurement technique and of the synchronization systems of the CMS hadron calorimeter. Time measurement performance results are presented from test beam data taken in the years 2004 and 2006. For hadronic showers of energy greater than 100 GeV, the timing resolution is measured to be about 1.2 ns. Time synchronization and out-of-time background rejection results are presented from the Cosmic Run At Four Tesla and LHC beam runs taken in the Autumn of 2008. The inter-channel synchronization is measured to be within ±2 ns

Astrocyte-to-neuron communication through integrin-engaged Thy-1/CBP/Csk/Src complex triggers neurite retraction via the RhoA/ROCK pathway.

Two key proteins for cellular communication between astrocytes and neurons are αvβ3 integrin and the receptor Thy-1. Binding of these molecules in the same (cis) or on adjacent (trans) cellular membranes induces Thy-1 clustering, triggering actin cytoskeleton remodeling. Molecular events that could explain how the Thy-1-αvβ3 integrin interaction signals have only been studied separately in different cell types, and the detailed transcellular communication and signal transduction pathways involved in neuronal cytoskeleton remodeling remain unresolved. Using biochemical and genetic approaches, single-molecule tracking, and high-resolution nanoscopy, we provide evidence that upon binding to αvβ3 integrin, Thy-1 mobility decreased while Thy-1 nanocluster size increased. This occurred concomitantly with inactivation and exclusion of the non-receptor tyrosine kinase Src from the Thy-1/C-terminal Src kinase (Csk)-binding protein (CBP)/Csk complex. The Src inactivation decreased the p190Rho GTPase activating protein phosphorylation, promoting RhoA activation, cofilin, and myosin light chain II phosphorylation and, consequently, neurite shortening. Finally, silencing the adaptor CBP demonstrated that this protein was a key transducer in the Thy-1 signaling cascade. In conclusion, these data support the hypothesis that the Thy-1-CBP-Csk-Src-RhoA-ROCK axis transmitted signals from astrocytic integrin-engaged Thy-1 (trans) to the neuronal actin cytoskeleton. Importantly, the β3 integrin in neurons (cis) was not found to be crucial for neurite shortening. This is the first study to detail the signaling pathway triggered by αvβ3, the endogenous Thy-1 ligand, highlighting the role of membrane-bound integrins as trans acting ligands in astrocyte-neuron communication

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

Search for D0 meson decays to π+π−e+e− and K+K−e+e− final states

A search for D0 meson decays to the πþπ−eþe− and KþK−eþe− final states is reported using a sample of proton-proton collisions collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb−1. The decay D0 → πþπ−eþe− is observed for the first time when requiring that the two electrons are consistent with coming from the decay of a φ or ρ0=ω meson. The corresponding branching fractions are measured relative to the D0 → K−π−1⁄2eþe−ρ0=ω decay, where the two electrons are consistent with coming from the decay of a ρ0 or ω meson. No evidence is found for the D0 → KþK−eþe− decay and world-best limits are set on its branching fraction. The results are compared to, and found to be consistent with, the branching fractions of the D0 → πþπ−μþμ− and D0 → KþK−μþμ− decays recently measured by LHCb and confirm lepton universality at the current precision