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Teaching Methodology for the Training of a Laparoscopic Technique: Intestinal Anastomosis

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Surgical Science 2017年第8期8卷 384-401页

作者： José Luis Ruiz-Gómez roberto fernández santiago Antonio López Useros Carlos Redondo-Figuero José C. Manuel-Palazuelos Instructor General Surgery Hospital Virtual Valdecilla Santander Spain Medical and Chirurgical Science University of Cantabria Santander Spain Hospital Virtual Valdecilla Santander Spain

Traditionally surgeons learned surgical techniques by training them directly in the patient by imitating the actions of the surgeon with more experience. Today this methodology is difficult to apply, since there are multiple factors that hinder its use. The limited time of training systems, scarcity of resources, patient safety or the need to learn new techniques of minimally invasive surgery, make the training of surgeons require a different learning methodology. This study has designed a new methodology for the learning of surgical techniques that minimizes the impact of all the previous factors on the training of surgeons. Its effectiveness in the teaching of laparoscopic manual intestinal anastomosis is analyzed. It has been asked a group of 24 expert surgeons teaching in intestinal anastomoses, which are the steps that must include the teaching of the technique. The phases evaluated with the highest score were included in the methodology. Once the steps of the methodology were designed, 25 general surgeons were chosen and divided into three groups according to their level of experience (experts, trained and beginners). Each participant performed five training sessions following the new methodology. The technical quality of the anastomosis, the overall development of the operation, as well as the feedback developed between the participants and the instructor was analyzed. After analyzing the results it was observed that structured feedback between the instructor and the participant increases the involvement of the participant in the learning process and reduces the time needed to acquire the competence. With this methodology the inexperienced participants perform the fifth anastomosis with quality parameters close to those obtained by the expert participants. In addition, this methodology allows to individualize the learning according to the needs of each participant.

关键词： Methodology Learn Surgery Anastomosis Intestinal

Multi-Step Clustering of Smart Meters Time Series:Application to Demand Flexibility Characterization of SME Customers

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 869-907页

作者： santiago Bañales Raquel Dormido Natividad Duro Department of Computer Sciences and Automatic Control Universidad Nacional de Educación a Distancia(UNED)Madrid28040Spain Iberdrola Innovation Middle East Doha210177Qatar

Customer segmentation according to load-shape profiles using smart meter data is an increasingly important application to vital the planning and operation of energy systems and to enable citizens’participation in the energy *** study proposes an innovative multi-step clustering procedure to segment customers based on load-shape patterns at the daily and intra-daily time *** meter data is split between daily and hourly normalized time series to assess monthly,weekly,daily,and hourly seasonality patterns *** dimensionality reduction implicit in the splitting allows a direct approach to clustering raw daily energy time series *** intraday clustering procedure sequentially identifies representative hourly day-unit profiles for each customer and the entire *** the first time,a step function approach is applied to reduce time series *** attributes embedded in surveys are employed to build external clustering validation metrics using Cramer’s V correlation factors and to identify statistically significant determinants of load-shape in energy *** addition,a time series features engineering approach is used to extract 16 relevant demand flexibility indicators that characterize customers and corresponding clusters along four different axes:available Energy(E),Temporal patterns(T),Consistency(C),and Variability(V).The methodology is implemented on a real-world electricity consumption dataset of 325 Small and Medium-sized Enterprise(SME)customers,identifying 4 daily and 6 hourly easy-to-interpret,well-defined *** application of the methodology includes selecting key parameters via grid search and a thorough comparison of clustering distances and methods to ensure the robustness of the *** research can test the scalability of the methodology to larger datasets from various customer segments(households and large commercial)and locations with different weather and socioeconomic conditio

关键词： Electric load clustering load profiling smart meters machine learning data mining demand flexibility demand response

Rock mass structural recognition from drill monitoring technology in underground mining using discontinuity index and machine learning techniques

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International Journal of Mining Science and Technology 2023年第5期33卷 555-571页

作者： Alberto fernández JoséA.Sanchidrián Pablo Segarra santiago Gómez Enming Li Rafael Navarro Universidad Politécnica de Madrid–ETSI Minas y Energía Spain Universidad de Salamanca–GIR Charrock Spain

A procedure to recognize individual discontinuities in rock mass from measurement while drilling(MWD)technology is developed,using the binary pattern of structural rock characteristics obtained from in-hole images for *** from two underground operations with different drilling technology and different rock mass characteristics are considered,which generalizes the application of the methodology to different sites and ensures the full operational integration of MWD data *** approaches are followed for site-specific structural model building:a discontinuity index(DI)built from variations in MWD parameters,and a machine learning(ML)classifier as function of the drilling parameters and their *** prediction ability of the models is quantitatively assessed as the rate of recognition of discontinuities observed in borehole *** between the parameters involved in the models for each site,and differences in their weights,highlight the site-dependence of the resulting *** ML approach offers better performance than the classical DI,with recognition rates in the range 89%to 96%.However,the simpler DI still yields fairly accurate results,with recognition rates 70%to 90%.These results validate the adaptive MWD-based methodology as an engineering solution to predict rock structural condition in underground mining operations.

关键词： Drill monitoring technology Rock mass characterization Underground mining Similarity metrics of binary vectors Structural rock factor Machine learning

Entrepreneurial, institutional and financialstrategies for FinTech profitability

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Financial Innovation 2022年第1期8卷 487-522页

作者： santiago Carbó-Valverde Pedro JCuadros-Solas Francisco Rodríguez-fernández University of Granada C/Campus Cartuja s/n18011 GranadaSpain CUNEF Universidad C/Pirineos5528040 MadridSpain Funcas C/Caballero de Gracia2828013 MadridSpain

Notwithstanding the emergence of FinTech startups in the financial services industry,most of these companies face significant difficulties in breaking even and *** study examines the main managerial, institutional, and financial drivers of FinTechprofitability and the time it takes for these firms to break even. The database includesrelevant qualitative factors, such as foundational characteristics, the technologicalprofile of the startup, and its funding structure. Using the full population of FinTechstartups operating in Spain from 2005 to 2017, we observe that most of these firms areunprofitable within three years of their inception. Combining panel data and survivalanalyses, we empirically find that large and solvent FinTech firms founded by singleentrepreneurs in an incubator or accelerator program are more likely to be profitableand prevail. FinTech firms reach their break-even points faster if they receive fundingthrough seed capital.

关键词： FinTech Profitability Entrepreneurship Technology Financial strategies Startups

Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in Fraxinus mandshurica

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Journal of Forestry Research 2022年第3期33卷 1005-1017页

作者： Hao Wang Dongyan Zhang Juan Luis fernández-Lorenzo Hailong Shen Ling Yang State Key Laboratory of Tree Genetics and Breeding School of ForestryNortheast Forestry UniversityHarbin150040People’s Republic of China Crop Production Department High Polytechnique School of EngineeringSantiago de Compostela UniversityLugoSpain

Programmed cell death occurs in browning explants of Fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons of zygotic embryos of F. mandshurica were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, and nitric oxide accumulation induced by high concentrations of sucrose and plant growth regulators were studied. The results show that plant growth regulators induced somatic embryogenesis and also promoted explant browning. High sucrose concentrations had similar effects. High concentrations of sucrose and plant growth regulators led to the accumulation of hydrogen peroxide and nitric oxide which induced changes in mitochondrial structure and function such as modifications in mitochondrial morphology, increased membrane permeability, decreased membrane potential, and the release of cytochrome c into the cytoplasm. An increase in caspase-3-like protease activity triggered programmed cell death in some browning explant cells. During somatic embryogenesis there were increased activities of superoxide dismutase, peroxidase, and catalase, which are associated with hydrogen peroxide metabolism and jointly maintain reactive oxygen species levels. Intracellular nitric oxide synthase and nitrate reductase activities were not significantly correlated with nitric oxide content. Instead, intracellular nitric oxide may be derived from non-enzymatic reactions. Our results indicate that hydrogen peroxide and nitric oxide may function as signals, playing key roles in somatic embryogenesis and programmed cell death of explant cells of F. mandshurica. The interaction between nitric oxide and reactive oxygen species determines the occurrence of programmed cell death in explant cells;somatic embryogenesis and programmed cell death are positively regulated by hydrogen peroxide. However, the regulation of nitric oxide is complex.

关键词： Manchurian ash Somatic embryogenesis Programmed cell death Mitochondria Reactive oxide species Nitric oxide

Safety of digoxin in nonagenarian patients with atrial fibrillation:lessons from the Spanish Multicenter Registry

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Journal of Geriatric Cardiology 2021年第10期18卷 809-815页

作者： Pablo Domínguez-Erquicia Sergio Raposeiras-Roubín Emad Abu-Assi María Cespón-fernández David Alonso-Rodríguez santiago Jesús Camacho-Freire Naiara Cubelos-fernández Álvaro López-Masjuán Ríos María Melendo-Viu AndrésÍñiguez-Romo Department of Cardiology University HospitalÁlvaro CunqueiroVigoSpain Health Research Institute Galicia Sur VigoSpain Department of Cardiology University Hospital of LeónLeónSpain Department of Cardiology University Hospital Juan Ramón JiménezHuelvaSpain

BACKGROUND The association between digoxin and mortality is an unclear *** older patients with atrial fibrillation(AF),where use of digoxin is frequent,the evidence of its safety is *** aim is to assess the safety of digoxin in nonagenarian patients with *** We evaluated data from 795 nonagenarian patients with non-valvular AF from the Spanish Multicenter *** analyzed the relationship between digoxin and all-cause mortality with the Cox proportional-hazards *** Follow-up was 27.7±18.3 *** age was 92.5±3.8 years,and 71%of nonagenarian patients were *** was not associated with increased risk of mortality[adjusted hazard ratio(aHR)=1.16,95%CI:0.96−1.41,P=0.130].However,we found a significant increase in mortality in the subgroup with estimated glomerular filtration rate(eGFR)<30 mL/min per 1.73 m^(2)(aHR=2.01,95%CI:1.13−3.57,P=0.018),but not in the other subgroups of eGFR(30−59 mL/min per 1.73 m^(2) and≥60 mL/min per 1.73 m^(2)).When exploring the risk of mortality according to sex,male subgroup was associated with an in-crease in mortality(aHR=1.48,95%CI:1.02−2.14,P=0.041).This was not observed in females subgroup(aHR=1.03,95%CI:0.81−1.29,P=0.829).Based on the presence or absence of heart failure,we did not find significant differences(aHR=1.20,95%CI:0.87−1.65,P=0.268 ***=1.15,95%CI:0.90−1.47,P=0.273,respectively).CONCLUSIONS In our large registry of nonagenarian patients with AF,we did not find an association between digoxin and mortality in the total ***,in the subgroup analyses,we found an increase in mortality with the use of digoxin in men and in patients with an eGFR<30 mL/min per 1.73 m^(2).

关键词： patients digoxin fibrillation

Statistical evaluation of fluoride contamination in groundwater resources of santiago del Estero Province, Argentina

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Geoscience Frontiers 2020年第6期11卷 2197-2205页

作者： K.Rondano Gómez C.E.López Pasquali G.Paniagua González P.fernández Hernando R.M.Garcinuño Martínez Departamento de Ciencias Básicas Facultad de Ciencias ForestalesUniversidad Nacional de Santiago Del EsteroArgentina Departamento de Ciencias Analíticas Facultad de CienciasUniversidad Nacional de Educación a DistanciaSpain Departamento de Química Analítica Facultad de Agronomía y AgroindustriasUniversidad Nacional de Santiago Del EsteroArgentina

This study investigates the suitability of statistical techniques for evaluating the fluoride content and the groundwater quality from Robles Department(RD)and Banda Department(BD)in santiago del Estero(Argentina).For the original statistical study,evaluation of nine parameters(fluoride,pH,conductivity,atmospheric and water temperature,total dissolved solids,chloride,hardness,and alkalinity)of 110 collected underground water samples from 23 dispersed rural areas was *** samples were obtained by sampling taken from wells at different *** levels were determined by a standard colorimetric method in two seasonal periods,the dry(from April to September)and rainy(from October to March)*** analytical results obtained for physicochemical parameters such as pH,total dissolved solids(TDS),and temperature does not reveal any notable difference between the rainy and dry seasons *** both seasons,the atmospheric temperature average was 22℃.With respect to fluoride content,approximately 50%of the analysed groundwater samples exceeded the limit established by current legislation(1.0 mg/L),obtaining concentration levels in the range of 0.01-2.80 mg/*** study demonstrates the usefulness of the univariate statistical method(quartiles calculation,interquartile range IQR),multivariate principal component analysis(PCA),and cluster analysis to establish a better understanding of the state of the contamination of the waters in the region studied.

关键词： Source water protection santiago del Estero Multivariate statistical analysis Fluoride Spectrophotometry

Recent advances in liver preconditioning: Thyroid hormone, n-3 long-chain polyunsaturated fatty acids and iron

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World Journal of Hepatology 2012年第4期4卷 119-128页

作者： Virginia fernández Gladys Tapia Luis A Videla Molecular and Clinical Pharmacology Program Institute of Biomedical Sciences Faculty of Medicine University of Chile Casilla 70000 Santiago-7 Chile

Liver preconditioning (PC), defined as an enhanced tolerance to injuring stimuli induced by previous specific maneuvers triggering beneficial functional and molecular changes, is of crucial importance in human liver transplantation and major hepatic resection. For these reasons, numerous PC strategies have been evaluated in experimental models of ischemia-reperfusion liver injury, which have not been transferred to clinical application due to side effects, toxicity and difficulties in implementation, with the exception of the controversial ischemic PC. In recent years, our group has undertaken the assessment of alternate experimental liver PC protocols that might have application in the clinical setting. These include thyroid hormone (T3), n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA), or iron, which suppressed liver damage due to the 1 h ischemia-20 h reperfusion protocol. T3, n-3 LCPUFA and iron are hormetic agents that trigger biologically beneficial effects in the low-dose range, whose multifactorial mechanisms of action are discussed in the work.

关键词： Liver preconditioning Thyroid hormone n-3 polyunsaturated fatty acids Iron

Risk factors associated with the development of ischemic colitis

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World Journal of Gastroenterology 2010年第36期16卷 4564-4569页

作者： Joaquín Cubiella fernández Luisa Núez Calvo Elvira González Vázquez Maria Jesús García García Maria Teresa Alves Pérez Isabel Martínez Silva Javier fernández Seara Department of Gastroenterology Complexo Hospitalario de Ourense32005 OurenseSpain Department of Internal Medicine Complexo Hospitalario de Ourense32005 OurenseSpain Department of Internal Medicine Fundación Pública Hospitalaria de Verín32600 VerinSpain Research Support Unit Complexo Hospitalario de Orense32005 OurenseSpain Biostatistic Unit University of Santiago de Compostela15703 Santiago de CompostelaSpain

AIM:To ascertain the role of cardiovascular risk factors,cardiovascular diseases,standard treatments and other diseases in the development of ischemic colitis(IC).METHODS:A retrospective,case-control study was designed,using matched data and covering 161 incident cases of IC who required admission to our hospital from 1998 through *** was diagnosed on the basis of endoscopic findings and diagnostic or compatible *** were randomly chosen from a cohort of patients who were admitted in the same period and required a colonoscopy,excluding those with diagnosis of *** were matched with controls(ratio 1:2),by age and sex.A conditional logistic regression was ***:A total of 483 patients(161 cases,322 con-trols)were included;mean age 75.67±10.03 years,55.9%*** principal indications for colonos-copy in the control group were lower gastrointestinal hemorrhage(35.4%),anemia(33.9%),abdominal pain(19.9%)and diarrhea(9.6%).The endoscopic findings in this group were hemorrhoids(25.5%),diverticular disease(30.4%),polyps(19.9%)and colorectal cancer(10.2%).The following variables were associated with IC in the univariate analysis:arterial hypertension(P= 0.033);dyslipidemia(P<0.001);diabetes mellitus(P =0.025);peripheral arterial disease(P=0.004);heart failure(P=0.026);treatment with hypotensive drugs(P=0.023);angiotensin-converting enzyme inhibitors;(P=0.018);calcium channel antagonists(P=0.028);and acetylsalicylic acid(ASA)(P<0.001).Finally,the following variables were independently associated with the development of IC:diabetes mellitus[odds ratio(OR)1.76,95%confidence interval(CI):1.001-3.077,P=0.046];dyslipidemia(OR 2.12,95%CI:1.26-3.57,P=0.004);heart failure(OR 3.17,95%CI:1.31-7.68,P=0.01);peripheral arterial disease(OR 4.1,95%CI:1.32-12.72,P=0.015);treatment with digoxin(digitalis)(OR 0.27,95%CI:0.084-0.857,P=0.026);and ASA(OR 1.97,95%CI:1.16-3.36,P=0.012).CONCLUSION:The development of an episode of IC was independently associat

关键词： Ischemic colitis Diabetes mellitus Dyslipidemia Acetylsalicylic acid Peripheral arterial disease Digoxin