634 results on '"Carlos Mena"'
Search Results
2. The atlas of unburnable oil for supply-side climate policies
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Lorenzo Pellegrini, Murat Arsel, Gorka Muñoa, Guillem Rius-Taberner, Carlos Mena, and Martí Orta-Martínez
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Science - Abstract
Abstract To limit the increase in global mean temperature to 1.5 °C, CO2 emissions must be drastically reduced. Accordingly, approximately 97%, 81%, and 71% of existing coal and conventional gas and oil resources, respectively, need to remain unburned. This article develops an integrated spatial assessment model based on estimates and locations of conventional oil resources and socio-environmental criteria to construct a global atlas of unburnable oil. The results show that biodiversity hotspots, richness centres of endemic species, natural protected areas, urban areas, and the territories of Indigenous Peoples in voluntary isolation coincide with 609 gigabarrels (Gbbl) of conventional oil resources. Since 1524 Gbbl of conventional oil resources are required to be left untapped in order to keep global warming under 1.5 °C, all of the above-mentioned socio-environmentally sensitive areas can be kept entirely off-limits to oil extraction. The model provides spatial guidelines to select unburnable fossil fuels resources while enhancing collateral socio-environmental benefits.
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- 2024
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3. Classification, military applications, and opportunities of unmanned aerial vehicles
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Linker Criollo, Carlos Mena-Arciniega, and Shen Xing
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military drones ,military capabilities ,modern military applications ,unmanned aerial vehicle ,UAV classification ,military operations ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
Unmanned aerial vehicles (UAVs) are cutting-edge technologies used for military purposes world-wide at tactical, operational, and strategic levels. This study provides an overview of the history and current state of military drones, considering a global and Ecuadorian background. Then, a classification of the UAVs developed and built in Ecuador is conducted based on their endurance, altitude, and wing span to understand the national context and progress. The research also delves into the applications of UAVs in several military operations and missions, aiming to create a framework that aligns UAV capabilities with specific operational needs; this permits the identification of the challenges and opportunities the country faces. Unmanned aerial systems have changed the battlefield, and the government needs to adapt to a national strategy that incorporates this technology; this research analyzes and provides insights to improve military capabilities such as exploring modern UAV military applications, technical updates in communication, navigation, and data acquisition systems; and the integration of emerging technologies like smart materials, artificial intelligence, and electric propulsion systems. This study provides valuable insights into the Ecuadorian UAVs that enhance the country’s military operations and offer some applications and uses of this technology for national security.
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- 2024
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4. Reply
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Kim G. Smolderen, PhD, Andrea W.M. Evers, PhD, Adrienne H. Kovacs, PhD, Idalia Massa-Carroll, PhD, and Carlos Mena-Hurtado, MD
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Published
- 2024
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5. Multi-modality imaging for assessment of the microcirculation in peripheral artery disease: Bench to clinical practice
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Santiago Callegari, Attila Feher, Kim G. Smolderen, Carlos Mena-Hurtado, and Albert J. Sinusas
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Peripheral artery disease (PAD) is a highly prevalent disorder with a high risk of mortality and amputation despite the introduction of novel medical and procedural treatments. Microvascular disease (MVD) is common among patients with PAD, and despite the established role as a predictor of amputations and mortality, MVD is not routinely assessed as part of current standard practice. Recent pre-clinical and clinical perfusion and molecular imaging studies have confirmed the important role of MVD in the pathogenesis and outcomes of PAD. The recent advancements in the imaging of the peripheral microcirculation could lead to a better understanding of the pathophysiology of PAD, and result in improved risk stratification, and our evaluation of response to therapies. In this review, we will discuss the current understanding of the anatomy and physiology of peripheral microcirculation, and the role of imaging for assessment of perfusion in PAD, and the latest advancements in molecular imaging. By highlighting the latest advancements in multi-modality imaging of the peripheral microcirculation, we aim to underscore the most promising imaging approaches and highlight potential research opportunities, with the goal of translating these approaches for improved and personalized management of PAD in the future.
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- 2024
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6. Long‐Term Mortality Predictors Using a Machine‐Learning Approach in Patients With Chronic Limb‐Threatening Ischemia After Peripheral Vascular Intervention
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Santiago Callegari, Gaëlle Romain, Jacob Cleman, Lindsey Scierka, Francky Jacque, Kim G. Smolderen, and Carlos Mena‐Hurtado
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chronic limb‐threatening ischemia ,machine learning ,mortality ,peripheral artery disease ,peripheral vascular intervention ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Patients with chronic limb‐threatening ischemia (CLTI) face a high long‐term mortality risk. Identifying novel mortality predictors and risk profiles would enable individual health care plan design and improved survival. We aimed to leverage a random survival forest machine‐learning algorithm to identify long‐term all‐cause mortality predictors in patients with CLTI undergoing peripheral vascular intervention. Methods and Results Patients with CLTI undergoing peripheral vascular intervention from 2017 to 2018 were derived from the Medicare‐linked VQI (Vascular Quality Initiative) registry. We constructed a random survival forest to rank 66 preprocedural variables according to their relative importance and mean minimal depth for 3‐year all‐cause mortality. A random survival forest of 2000 trees was built using a training sample (80% of the cohort). Accuracy was assessed in a testing sample (20%) using continuous ranked probability score, Harrell C‐index, and out‐of‐bag error rate. A total of 10 114 patients were included (mean±SD age, 72.0±11.0 years; 59% men). The 3‐year mortality rate was 39.1%, with a median survival of 1.4 years (interquartile range, 0.7–2.0 years). The most predictive variables were chronic kidney disease, age, congestive heart failure, dementia, arrhythmias, requiring assisted care, living at home, and body mass index. A total of 41 variables spanning all domains of the biopsychosocial model were ranked as mortality predictors. The accuracy of the model was excellent (continuous ranked probability score, 0.172; Harrell C‐index, 0.70; out‐of‐bag error rate, 29.7%). Conclusions Our random survival forest accurately predicts long‐term CLTI mortality, which is driven by demographic, functional, behavioral, and medical comorbidities. Broadening frameworks of risk and refining health care plans to include multidimensional risk factors could improve individualized care for CLTI.
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- 2024
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7. Colesteatoma del conducto auditivo complicado con absceso retroauricular
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Ashiria Reseda Acuña Ramírez, Jorge Roig Ocampos, and Carlos Mena Canata
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colesteatoma del conducto ,estenosis del conducto ,oído externo ,Medicine (General) ,R5-920 - Abstract
El Colesteatoma del Conducto Auditivo Externo (CCAE) constituye una patología poco frecuente. Su diagnóstico es fundamentalmente clínico, se apoya en los estudios de imagen y confirmación final anatomopatológica. Algunos casos pueden ser asintomáticos y otros casos pueden presentar complicaciones como parálisis facial, afectación del oído medio, etc. Su tratamiento es quirúrgico con una serie de técnicas denominadas canaloplastias, las cuales tienen como objetivo retirar el tejido colesteatomatoso y crear un mecanismo de autoevacuación. Presentamos la descripción de un caso de colesteatoma del conducto auditivo complicado con absceso retroauricular en una paciente joven con estenosis congénita, discutimos los aspectos relevantes respecto a la clínica, diagnósticos diferenciales y opciones terapéuticas en una revisión de la literatura disponible.
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- 2024
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8. Thyroid cancer in patients undergoing thyroidectomy total in the Otorhinolaryngology Department of the Hospital de Clínicas during the period 2018-2022
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Ricardo Serrano, Carlos Mena-Canata, Raúl Tornaco-Maidana, and Marcelo Villalba
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cáncer de tiroides ,tiroidectomía ,tumor ,cirugía de tiroides ,Medicine (General) ,R5-920 - Abstract
Introduction: Thyroid cancer, considered one of the most frequent malignant tumors of the endocrine system, accounts for 80%–90% of cases. The most common histological type observed in most studies is papillary cancer. Objective: To determine the frequency of thyroid cancer in patients undergoing total thyroidectomy at the Otorhinolaryngology Department of the Hospital de Clínicas between the period 2018-2022. Methodology: This retrospective study included 260 patients treated during the study period. Data were obtained from the patients' medical records, and sociodemographic and clinical variables related to thyroid cancer were analyzed. Data were analyzed with the SPSS v25 program, using descriptive statistics. Results: The frequency of thyroid cancer was 48.1%. The mean age of the cancer patients was 42.10±13.10 years. A higher frequency was observed in females 34.2%, n=89) and among those aged 25-44 years 20.0%, n=52). The most frequent were papillary (36.9%), follicular (2.7%), medullary (1.5%), and anaplastic (1.2%) types. Discussion: The frequency of thyroid cancer is high; it is more common in women and as age increases.
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- 2024
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9. Successful percutaneous management of hypothenar hammer syndrome with thrombosuction and catheter-directed intra-arterial thrombolysis
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Abhinav Aggarwal, MD, Jan T. Markiel, MD, Nishith Chandra, MD, DM, Gregory K. Buller, MD, FACP, Kim G. Smolderen, PhD, MSc, and Carlos Mena-Hurtado, MD, FACC, FSCAI, FAHA
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Acute limb ischemia ,Arterial thrombosis ,Hand ischemia ,Peripheral artery disease ,Revascularization ,Vascular medicine ,Surgery ,RD1-811 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Hypothenar hammer syndrome (HHS) is a rare vascular disorder leading to ulnar artery thrombosis or aneurysm and causing acute or chronic limb ischemia. The optimal approaches to managing this condition lack a definitive consensus and are essentially empirical, typically necessitating conservative methods for symptomatic relief, with surgical intervention reserved for cases for which conservative measures prove inadequate or when acute limb ischemia ensues. Limited data are available on percutaneous management for this condition. We present the case of a 36-year-old male powerlifter who developed acute digital ischemia due to HHS in the left hand that was managed successfully through an innovative approach using antegrade left brachial artery access and combining percutaneous thrombosuction and intra-arterial thrombolysis. This comprehensive approach resulted in restoration of blood flow and resolution of acute limb ischemia. The patient was subsequently prescribed short-term anticoagulation therapy and remained symptom free at 3 months of follow-up. This innovative strategy challenges traditional surgical approaches in HHS management, underscoring the importance of using minimally invasive techniques as a promising alternative and highlighting potential avenues for further research.
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- 2024
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10. Examining Outcomes in Patients Admitted With Comorbid Peripheral Artery Disease and Microvascular Disease
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Scott Grubman, Miguel Algara, Kim G. Smolderen, Paulina Luna, Kristie Walenczyk, Lindsey Scierka, Jacob Cleman, Waleed Tariq Siddiqui, Gaëlle Romain, and Carlos Mena‐Hurtado
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amputations ,microvascular disease ,mortality ,peripheral artery disease ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Peripheral artery disease (PAD) and microvascular disease (MVD) are highly prevalent conditions that share common risk factors. This observational study aimed to characterize patients with both conditions and determine the impact of comorbid PAD/MVD on outcomes. Methods and Results Patients admitted across 31 states January 2011 through December 2018 with a primary or secondary diagnosis of PAD or MVD were included from the National Readmissions Database and weighted to approximate a national sample. Those age 500 000 in 2018. Major and minor amputations increased ≈50% for PAD/MVD between 2011 and 2018. Compared with PAD‐only, PAD/MVD was associated with a higher risk for major amputation (odds ratio [OR], 1.30 [95% CI, 1.28–1.32]), minor amputation (OR, 2.15 [95% CI, 2.12–2.18]), major adverse cardiac events (OR, 1.04 [95% CI, 1.03–1.04]), in‐hospital mortality (OR, 1.07 [95% CI, 1.05–1.09]), and readmission (hazard ratio, 1.02 [95% CI, 1.02–1.02]) after adjustment for baseline factors. Conclusions Comorbid MVD is present in a large and growing number of patients with PAD and is associated with augmented risk for adverse outcomes. Further prospective research is merited to understand this vulnerable population.
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- 2024
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11. Drug‐Coated Balloon and Drug‐Eluting Stent Safety in Patients With Femoropopliteal and Severe Chronic Kidney Disease
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Jonathan Hanna, Kim G. Smolderen, Yulanka Castro‐Dominguez, Gaëlle Romain, Megan Lee, Jeffrey Turner, and Carlos Mena‐Hurtado
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chronic kidney disease ,drug‐coated balloon ,drug‐eluting stent ,peripheral artery disease ,revascularization ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Patients with severe‐stage chronic kidney disease (CKD) were excluded from femoropopliteal disease trials evaluating drug‐coated balloons (DCBs) and drug‐eluting stents (DESs) versus plain balloon angioplasty (POBA) and bare metal stents (BMSs). We examined the interaction between CKD status and device type for the association with 24‐month all‐cause mortality and major amputation risk. Methods and Results We studied patients undergoing femoropopliteal interventions (September 2016–December 2018) from Medicare‐linked VQI (Vascular Quality Initiative) registry data. We compared outcomes for: (1) early‐stage CKD (stages 1–3) receiving DCB/DES, (2) early‐stage CKD receiving POBA/BMS, (3) severe‐stage (4 and 5) CKD receiving DCB/DES, and (4) severe‐stage CKD receiving POBA/BMS. We studied 8799 patients (early‐stage CKD: 94%; severe‐stage: 6%). DCB/DES use was 57% versus 51% in patients with early‐stage versus severe‐stage CKD. Twenty‐four‐month mortality risk for patients with early‐stage CKD receiving DCB/DES (reference) was 21% versus 28% (hazard ratio [HR], 1.47 [95% CI, 1.31–1.65]) for those receiving POBA/BMS; patients with severe‐stage CKD: those receiving DCB/DES had a 49% (HR, 2.61 [95% CI, 2.06–3.31]) mortality risk versus 52% (HR, 3.64 [95% CI, 2.91–4.55]) for those receiving POBA/BMS (interaction P
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- 2023
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12. Infiltración transtimpánica de corticoides para el tratamiento de los acúfenos subjetivos en pacientes del Hospital de Clínicas de Julio-Agosto 2021
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Ricardo Serrano-Andrade, Carlos Mena Canata, Ta Ju Liu, and Raúl Tornaco-Maidana
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corticoides ,transtimpánica ,dexametasona ,acúfeno ,Medicine (General) ,R5-920 - Abstract
Introducción: El acúfeno es un problema que afecta a una parte importante de la población, cuyas causas no están del todo claras. Actualmente no existe una cura ni consenso sobre el tratamiento de los acúfenos los cuales resultan ineficaces en muchos casos, se acompañan de efectos secundarios importantes o no proporcionan un alivio sintomatico a los pacientes. Se ha reportado que la inyección intratimpática de corticoesteroides mejora los síntomas. Objetivo: determinar el resultado de la infiltración transtimpánica de corticoides para el tratamiento de los acúfenos subjetivos. Metodología: El diseño es del estudio es observacional, descriptivo y correlacional, de muestreo fue no probabilístico de casos consecutivos. Se incluyó pacientes mayores de edad con acúfenos uni o bilateral de más de un mes de evolución como síntoma principal. Resultados: Se incluyó a 25 pacientes en la investigación, la mayor parte era del sexo masculino con una media de edades de aproximadamente 45 años. El principal tipo de pérdida auditiva asociado a estos pacientes fue la de tipo neurosensorial. No se encontraron diferencias audiométricas entre el pre y post infiltración. Conclusión: Un gran porcentaje de los pacientes presentaba alto grado de discapacidad por acúfenos y síntomas moderados a graves previo al tratamiento, posterior al mismo, este disminuyo, pero no de manera significativa.
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- 2022
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13. Endovascular aneurysm repair with inferior mesenteric artery chimney in a high-risk patient with abdominal aortic aneurysm and iliac occlusion
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Valentyna Kostiuk, BA, Carlos Mena, MD, Bauer Sumpio, MD, PhD, Raul J. Guzman, MD, and Cassius Iyad Ochoa Chaar, MD, MS
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Abdominal aortic aneurysm ,Chimney graft ,Endovascular aneurysm repair (EVAR) ,Inferior mesenteric artery ,Surgery ,RD1-811 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
A 63-year-old man presented for the treatment of abdominal aortic aneurysm in the setting of bilateral internal iliac artery compromise from prior peripheral arterial disease treatments. The inferior mesenteric artery (IMA) measured 5 mm. Patient underwent coronary artery stenting 6 months prior and experienced left leg claudication. He underwent endovascular aneurysm repair with chimney IMA grafting and a femorofemoral bypass with uneventful recovery. At 1 year, computed tomography angiogram shows no flow in the aneurysm sac, and his left leg claudication resolved. Endovascular aneurysm repair with chimney IMA grafting for colonic perfusion preservation is a reasonable alternative to open surgical repair with IMA reimplantation in high-risk patients.
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- 2022
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14. Abnormal nodal and global network organization in resting state functional MRI from subjects with the 22q11 deletion syndrome
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Teuntje A. D. Pelgrim, Matthijs G. Bossong, Analía Cuiza, Luz María Alliende, Carlos Mena, Angeles Tepper, Juan Pablo Ramirez-Mahaluf, Barbara Iruretagoyena, Claudia Ornstein, Rosemarie Fritsch, Juan Pablo Cruz, Cristian Tejos, Gabriela Repetto, and Nicolas Crossley
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Medicine ,Science - Abstract
Abstract The 22q11 deletion syndrome is a genetic disorder associated with a high risk of developing psychosis, and is therefore considered a neurodevelopmental model for studying the pathogenesis of schizophrenia. Studies have shown that localized abnormal functional brain connectivity is present in 22q11 deletion syndrome like in schizophrenia. However, it is less clear whether these abnormal cortical interactions lead to global or regional network disorganization as seen in schizophrenia. We analyzed from a graph-theory perspective fMRI data from 40 22q11 deletion syndrome patients and 67 healthy controls, and reconstructed functional networks from 105 brain regions. Between-group differences were examined by evaluating edge-wise strength and graph theoretical metrics of local (weighted degree, nodal efficiency, nodal local efficiency) and global topological properties (modularity, local and global efficiency). Connectivity strength was globally reduced in patients, driven by a large network comprising 147 reduced connections. The 22q11 deletion syndrome network presented with abnormal local topological properties, with decreased local efficiency and reductions in weighted degree particularly in hub nodes. We found evidence for abnormal integration but intact segregation of the 22q11 deletion syndrome network. Results suggest that 22q11 deletion syndrome patients present with similar aberrant local network organization as seen in schizophrenia, and this network configuration might represent a vulnerability factor to psychosis.
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- 2021
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15. Peripheral Artery Disease Screening in the Community and 1-Year Mortality, Cardiovascular Events, and Adverse Limb Events
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Kim G. Smolderen, PhD, Omid Ameli, MD, DrPH, Christine E. Chaisson, MPH, Kevin Heath, MD, MHL, and Carlos Mena-Hurtado, MD
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Peripheral artery disease ,vascular ,screening ,prevention ,outcomes ,risk stratification ,Public aspects of medicine ,RA1-1270 - Abstract
Introduction: This study aimed to examine all-cause mortality, 1- and 2-year major cardiovascular events, and major adverse limb events in individuals aged ≥65 years who received an in-home health visit with peripheral artery disease screening. In addition, we compared 1-year healthcare utilization before and after peripheral artery disease screening for those who screened positive. Setting/Participants: Medicare Advantage beneficiaries aged ≥65 years participating in the Optum HouseCalls program in the U.S. between April 1, 2017 and February 1, 2019 were included. Intervention: The intervention consisted of a peripheral artery disease screening program using a plethysmography system. Main outcome measures: One-year all-cause mortality as a landmark analysis, 1- and 2-year major cardiovascular events, and major adverse limb events after screening were compared by peripheral artery disease screen status using claims data. We compared cardiovascular medications and revascularization procedures between the year before and after the peripheral artery disease screening event for those with peripheral artery disease. Results: Of 192,500 beneficiaries, 27.7% screened positive. One-year all-cause mortality rates for those who screened positive for peripheral artery disease versus those who screened negative were higher (1.51% vs 0.89%; p
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- 2022
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16. Overview of School-Based Telehealth Network Grant Program Services Delivered to Students in Rural Schools
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Marcia M. Ward, Divya Bhagianadh, Fred Ullrich, Kimberly A. S. Merchant, and Carlos Mena
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Telehealth can expand and enhance access to school-based health care, but its use has been relatively limited. Recognizing that school-based health care is still not reaching many students, the Health Resources and Services Administration (HRSA) funded the School Based Telehealth Network Grant Program to expand telehealth in rural school-based settings to help to increase the availability and use of these services. The 19 grantees delivered telehealth to over 200 schools across 17 states, choosing which services they would deliver and how. Looking across the services, these fell into three categories -- primary/urgent care, behavioral health, and other more specialized services. The majority of grantees offered multiple telehealth services with the combination of behavioral health and primary/urgent care the most common. The current study adds to the literature by elucidating that telehealth in schools can address multiple clinical conditions through separate services even though doing so involves using various combinations of clinicians providing different services.
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- 2024
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17. Intervention to Increase Cervical Cancer Screening Behavior among Medically Underserved Women: Effectiveness of 3R Communication Model
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Matthew Asare, Anjelica Elizondo, Mina Dwumfour-Poku, Carlos Mena, Mariela Gutierrez, and Hadii M. Mamudu
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3R communication model ,self-sampling ,medically underserved women ,cervical cancer screening ,Medicine - Abstract
Human Papillomavirus (HPV) self-sampling has the potential to increase Cervical Cancer Screening (CCS) and reduce the cervical cancer burden in Medically Underserved Women (MUW). However, interventions promoting self-sampling are limited. We examined the effectiveness of an intervention study in increasing CCS among MUW. We conducted a quasi-experimental intervention study. A face-to-face verbal approach was used to recruit MUW (n = 83, mean age 48.57 ± 11.02) living in a small city in the US. Behavioral intervention based on reframing, reprioritizing, and reforming (3R model) was used to educate the women about CCS in a group format. The women (n = 83) completed pre-and post-intervention assessments, and 10 of them were invited for follow-up interviews. The primary outcome was CCS uptake. Mixed methods analyses were conducted using a t-test for the primary outcome, PROCESS for mediation analysis, and NVivo for interview data. The majority of women (75%) completed self-testing. High-risk HPV among women was 11%, and of those, 57% followed up with physicians for care. We found that the significant increase in the women’s post-intervention screening behaviors was mediated by the increase in knowledge (Indirect Effect [IE] = 0.1314; 95% CI, 0.0104, 0.4079) and attitude (IE = 0.2167; 95% CI, 0.0291, 0.6050) scores, (p < 0.001). Interview analyses offered further explanations why MUW found the intervention messages acceptable (encourages proactive behavior), feasible (simple and easy to understand), and appropriate (helpful and informative). Barriers, including lack of trust and fear of results, were identified. The findings suggest that an intervention that combines the 3R model and self-sampling may increase CCS among MUW.
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- 2023
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18. Nutrition, dietary habits, and weight management to prevent and treat patients with peripheral artery disease
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Marios Sagris, Damianos G Kokkinidis, Ioannis G. Lempesis, Stefanos Giannopoulos, Loukianos Rallidis, Carlos Mena-Hurtado, and Christos Bakoyiannis
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peripheral artery disease ,critical limb ischemia ,nutrition ,diets ,weight loss ,prevention ,treatment ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Peripheral artery disease (PAD) affects 3%-10% of the Western population and if remains untreated can have devastating consequences to patients and their families. This review article analyzes how healthy dietary habits can decrease PAD rates when applied in the general population. The aim is to focus on dietary, nutritional and weight management interventions in patients with established PAD. Most adults with PAD are overweight or obese, while three out of four patients are characterized by deficiencies in vitamins and minerals. Weight loss interventions when needed and specialized dietary plans should be routinely recommended in patients with PAD. Appropriate nutritional support is of paramount importance in patients with advanced stages of PAD (critical limb ischemia).
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- 2020
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19. Post-traumatic stress in people from the interior drylands of the Maule region, Chile in the context of climate change
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Cristian Cáceres, Marcelo Leiva-Bianchi, Yony Ormazábal, Carlos Mena, and Juan Carlos Cantillana
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Environment ,post-traumatic stress disorder ,Getis Ord ,Curepto ,Pencahue ,Chile. ,Geography (General) ,G1-922 - Abstract
Progressive changes in local environmental scenarios, accelerated by global climate change, can negatively affect the mental health of people who inhabit these areas. The magnitude of these effects may vary depending on the socioeconomic conditions of people and the characteristics of the environment, so certain territories can be more vulnerable than others. In this context, the present study aimed to geographically analyse the levels of psychosocial impact and the types of disruptive responses related to the new territorial scenarios caused by climate change in the coastal drylands of the Maule region, Chile. For this purpose, 223 people from two communes (Curepto and Pencahue) were psychosocially evaluated for post-traumatic stress disorder (PTSD) together with a survey of the prevailing sociodemographic and socioeconomic conditions in relation to the environmental variables of the territory. All information was georeferenced, stored within an ArcGIS Desktop geographic information system (GIS) and then investigated by application of contingency tables, ANOVA and local clustering analysis using SSP statistical software. The results indicated a high level of PTSD in the population, with significant differences related to age and education as well as employment conditions and income. The spatial results showed high PTSD values in the communal capital of Curepto in the central agricultural valley near the estuary of the local river, while the existence of coldspots was observed in the central valley of the Pencahue commune. It was concluded that proximity to population centres and surface water sources played the greatest role for the development of PTSD.
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- 2022
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20. The shifting care and outcomes for patients with endangered limbs – Critical limb ischemia (SCOPE-CLI) registry overview of study design and rationale
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Lindsey E. Scierka, Carlos Mena-Hurtado, Mehdi H. Shishehbor, John A. Spertus, Sameer Nagpal, Trissa Babrowski, Matthew C. Bunte, Amani Politano, Misty Humphries, Jayer Chung, Lee Kirksey, Olamide Alabi, Peter Soukas, Sahil Parikh, Rumi Faizer, Robert Fitridge, Jeremy Provance, Gaëlle Romain, Neil McMillan, Nancy Stone, Kate Scott, Christine Fuss, Christina M. Pacheco, Kensey Gosch, Avis Harper-Brooks, and Kim G. Smolderen
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Peripheral Artery Disease ,Critical Limb Ischemia ,Study Design ,Registries ,Patient-Reported Outcomes ,Health Disparities ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Critical limb ischemia (CLI), the most severe form of peripheral artery disease, is associated with pain, poor wound healing, high rates of amputation, and mortality (>20% at 1 year). Little is known about the processes of care, patients’ preferences, or outcomes, as seen from patients’ perspectives. The SCOPE-CLI study was co-designed with patients to holistically document patient characteristics, treatment preferences, patterns of care, and patient-centered outcomes for CLI. Methods: This 11-center prospective observational registry will enroll and interview 816 patients from multispecialty, interdisciplinary vascular centers in the United States and Australia. Patients will be followed up at 1, 2, 6, and 12 months regarding their psychosocial factors and health status. Hospitalizations, interventions, and outcomes will be captured for 12 months with vital status extending to 5 years. Pilot data were collected between January and July of 2021 from 3 centers. Results: A total of 70 patients have been enrolled. The mean age was 68.4 ± 11.3 years, 31.4% were female, and 20.0% were African American. Conclusions: SCOPE-CLI is uniquely co-designed with patients who have CLI to capture the care experiences, treatment preferences, and health status outcomes of this vulnerable population and will provide much needed information to understand and address gaps in the quality of CLI care and outcomes.ClinicalTrials.gov identifier (NCT Number): NCT04710563 https://clinicaltrials.gov/ct2/show/NCT04710563.
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- 2022
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21. Derivation and validation of a predictive model for chronic stress in patients with cardiovascular disease
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Ali O. Malik, Philip G. Jones, Carlos Mena-Hurtado, Matthew M. Burg, Mehdi H. Shishehbor, Vittal Hejjaji, Andy Tran, John A. Spertus, and Kim G. Smolderen
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Medicine ,Science - Abstract
Background Chronic stress in patients with cardiovascular disease (CVD), including peripheral artery disease (PAD), is independently associated worse outcomes. A model that can reliably identify factors associated with risk of chronic stress in patients with CVD is needed. Methods In a prospective myocardial infarction (MI) registry (TRIUMPH), we constructed a logistic regression model using 27 patient demographic, socioeconomic, and clinical factors, adjusting for site, to identify predictors of chronic stress over 1 year. Stress at baseline and at 1-, 6- and 12-month follow-up was measured using the 4-item Perceived Stress Scale (PSS-4) [range 0–16, scores ≥6 depicting high stress]. Chronic stress was defined as at least 2 follow-up PSS-4 scores ≥6. We identified and validated this final model in another prospective registry of patients with symptomatic PAD, the PORTRAIT study. Results Our derivation cohort consisted of 4,340 patients with MI (mean age 59.1 ± 12.3 years, 33% females, 30% non-white), of whom 30% had chronic stress at follow-up. Of the 27 factors examined, female sex, current smoking, socioeconomic status, and economic burden due to medical care were positively associated with chronic stress, and ENRICHD Social Support Instrument (ESSI) score and age were inversely related to chronic stress. In the validation cohort of 797 PAD patients (mean age 68.6±9.7 years, 42% females, 28% non-white, 18% chronic stress) the c-statistic for the model was 0.77 and calibration was excellent. Conclusions We can reliably identify factors that are independently associated with risk of chronic stress in patients with CVD. As chronic stress is associated with worse outcomes in this population, our work identifies potential targets for interventions to as well as the patients that could benefit from these.
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- 2022
22. Cuerpo extraño en fosas nasales y conducto auditivo externo en el Hospital de Clínicas
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Raul Andrés Tornaco Maidana, Francisco Adrián Pires Cardozo, Carlos Mena Canata, Enrique Pérez Girala, and César Franco Peña
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Cuerpo extraño ,Cavidad Nasal ,Conducto auditivo externo ,Extracción ,Medicine (General) ,R5-920 - Abstract
Introducción: La presencia de cuerpo extraño en cavidad nasal u ótica es un problema frecuente en pediatría, porque puede producir secuelas severas para la salud del paciente. Estratificar por edades nos ayudaría a definir las medidas más apropiadas ente estos eventos en las distintas edades. Objetivo: Conocer la diferencia de media de edades entre pacientes con cuerpo extraño ótico y nasal. Metodología: Estudio observacional descriptivo con componentes analíticos, de muestreo aleatorio simple. De pacientes pediátricos del Hospital de Clínicas con antecedentes de introducción de cuerpo extraño en fosas nasales y conducto auditivo externo de enero a junio del 2019. Resultados: Fueron analizadas 182 interconsultas al servicio de otorrinolaringología, de pacientes pediátricos con antecedente de cuerpo extraño en oído o fosa nasal. El 47,81 % era del sexo femenino. En el 58,79 % de los casos el motivo de consulta era cuerpo extraño en fosa nasal y en el 41,21 % en oído. Los métodos de extracción más frecuentes fueron la cureta nasal (87,85 %) y el lavado de oído (54,67 %). Los cuerpos extraños más frecuente fue piezas de bijouteri. Solo 2 (1,09 %) pacientes requirieron internación (ambos con retraso en el desarrollo sicomotor) y extracción bajo sedación. El tratamiento más usado posterior a la extracción de oído fue antibióticos tópicos (52 %) y; antibióticos orales combinados con lavados nasales (28,97 %) para los de fosa nasal. La media de edades de pacientes con cuerpo extraño en fosa nasal fue de 2,97 años y en oído 5,59 años, significativamente mayor (p
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- 2022
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23. A dengue outbreak in a rural community in Northern Coastal Ecuador: An analysis using unmanned aerial vehicle mapping.
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Gwenyth O Lee, Luis Vasco, Sully Márquez, Julio C Zuniga-Moya, Amanda Van Engen, Jessica Uruchima, Patricio Ponce, William Cevallos, Gabriel Trueba, James Trostle, Veronica J Berrocal, Amy C Morrison, Varsovia Cevallos, Carlos Mena, Josefina Coloma, and Joseph N S Eisenberg
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
Dengue is recognized as a major health issue in large urban tropical cities but is also observed in rural areas. In these environments, physical characteristics of the landscape and sociodemographic factors may influence vector populations at small geographic scales, while prior immunity to the four dengue virus serotypes affects incidence. In 2019, a rural northwestern Ecuadorian community, only accessible by river, experienced a dengue outbreak. The village is 2-3 hours by boat away from the nearest population center and comprises both Afro-Ecuadorian and Indigenous Chachi households. We used multiple data streams to examine spatial risk factors associated with this outbreak, combining maps collected with an unmanned aerial vehicle (UAV), an entomological survey, a community census, and active surveillance of febrile cases. We mapped visible water containers seen in UAV images and calculated both the green-red vegetation index (GRVI) and household proximity to public spaces like schools and meeting areas. To identify risk factors for symptomatic dengue infection, we used mixed-effect logistic regression models to account for the clustering of symptomatic cases within households. We identified 55 dengue cases (9.5% of the population) from 37 households. Cases peaked in June and continued through October. Rural spatial organization helped to explain disease risk. Afro-Ecuadorian (versus Indigenous) households experience more symptomatic dengue (OR = 3.0, 95%CI: 1.3, 6.9). This association was explained by differences in vegetation (measured by GRVI) near the household (OR: 11.3 95% 0.38, 38.0) and proximity to the football field (OR: 13.9, 95% 4.0, 48.4). The integration of UAV mapping with other data streams adds to our understanding of these dynamics.
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- 2021
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24. Association of sleep apnea with outcomes in peripheral artery disease: Insights from the PORTRAIT study.
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Qurat-Ul-Ain Jelani, Carlos Mena-Hurtado, Kensey Gosch, Moghniuddin Mohammed, Clementine Labrosciano, Christopher Regan, Lindsey E Scierka, John A Spertus, Sameer Nagpal, and Kim G Smolderen
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Medicine ,Science - Abstract
BackgroundSleep apnea is a predictor of adverse cardiovascular outcome in many cardiovascular diseases but whether it is associated with worse health status outcomes or mortality in peripheral artery disease (PAD) is unknown.MethodsPORTRAIT is an international (US, Netherlands, Australia) prospective PAD registry that consecutively enrolled patients who presented with new-onset or recent exacerbations of PAD symptoms to any of 16 vascular specialty clinics. Health status was assessed upon presentation and at 12 months with the disease-specific Peripheral Artery Questionnaire (PAQ). Higher PAQ scores indicate better health status. A sequentially-adjusted hierarchical linear regression model examined the association between sleep apnea and 1-year PAQ symptoms, quality of life, and summary scores. Five-year survival curves by comorbid sleep apnea status for US patients were compared using the log-rank test.ResultsThe mean age of the 1204 PORTRAIT participants was 67.6 ± 9.4 years with 37.5% women and 8.3% (n = 100) having sleep apnea. Patients with sleep apnea were more likely to be from the US, more sedentary, and to have diabetes, obesity, coronary disease, more depressive symptoms and a history of prior peripheral interventions. Paradoxically, they also had higher ankle-brachial indices, but lower PAQ Summary scores at presentation and 12 months (41.2 ± 22.0 vs. 49. 9± 21.6 and 58.6 ± 27.9 vs. 71.3 ± 24.9, respectively, p = ConclusionIn patients presenting with PAD, comorbid sleep apnea is independently associated with worse health status over time. Future studies should test whether better treatment of sleep apnea can improve the health status of patients with PAD.Clinical trial registrationNCT01419080.
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- 2021
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25. Changes in geographic clustering of post-traumatic stress disorder and post-traumatic growth seven years after an earthquake in Cauquenes, Chile
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Marcelo Leiva-Bianchi, Carlos Mena, Yony Ormazábal, Carlos Serrano, and Pedro Rojas
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Post-traumatic stress disorder ,post-traumatic growth ,earthquake ,Geographic Information Systems ,Moran’s I ,Getis-Ord Gi* ,Geography (General) ,G1-922 - Abstract
Recent findings indicate that both disruptive Post-Traumatic Stress Disorder (PTSD) and healthy Post-Traumatic Growth (PTG) responses have some spatial distribution depending on where they are measured and the different degrees of exposure that people may have to a critical event (e.g., earthquake). Less is known about how these responses change as a function of space and time after these events. The objective of this study was to enter deeper into this relationship analysing how PTSD and PTG responses vary in their spatial distribution 6 and 7 years after an earthquake (such as the one that occurred on 27 February, 2010 in Cauquenes City, Chile). Spatial analyses based on Geographic Information Systems (GIS) were performed to detect global and local geographic clustering. Investigating 171 (2016) and 106 (2017) randomly selected adults from Cauquenes, we demonstrated that 7 years after the event only 4 variables were spatially clustered, i.e. personal mental strength, interpersonal relations, new possibilities and appreciation of life), all of them PTG dimensions; This result contrasted with the situation the previous year (2016), when 7 variables were clustered (total PTG, spiritual change, new possibilities, appreciation of life, PTSD symptoms, PTSD reactions and PTSD in total). The spatial identifications found could facilitate the comparison of mental health conditions in populations and the impact of recovery programmes in communities exposed to disasters.
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- 2020
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26. Association of Diabetes Mellitus With Health Status Outcomes in Patients With Peripheral Artery Disease: Insights From the PORTRAIT Registry
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Krishna K. Patel, Hani Alturkmani, Kensey Gosch, Carlos Mena‐Hurtado, Mehdi H. Shishehbor, Poghni A. Peri‐Okonny, Mark A. Creager, John A. Spertus, and Kim G. Smolderen
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diabetes mellitus ,health‐related quality of life ,peripheral artery disease ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Patients with peripheral artery disease (PAD) and coexisting diabetes mellitus (DM) have greater PAD progression and adverse limb events. Our aim was to study whether PAD‐specific health status differs by DM. Methods and Results The PORTRAIT (Patient‐Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) trial is a 16‐center international registry that includes patients with recent exacerbations or new‐onset symptomatic PAD presenting to specialty clinics. We assessed PAD‐specific health status initially and at 3, 6, and 12 months (Peripheral Artery Questionnaire [PAQ]). We used hierarchical, multivariable, linear regression, and repeated measures analyses to study the association between DM and baseline health status initially and over 3 to 12 months. Models were adjusted for demographics, socioeconomic factors, PAD severity, comorbidities, and psychosocial characteristics. The interaction of DM with PAD revascularization on 3‐ to 12‐month health status was also tested. Of 1204 patients, 398 (33%) had DM (94% type 2). Patients with versus those without DM had lower unadjusted PAQ summary scores at baseline and 3, 6, and 12 months (46.1 versus 50.8, 63.6 versus 68.2, 65.7 versus 71.7, and 65.4 versus 72.6; P≤0.01). In fully adjusted models, the effect of DM on baseline (mean difference, −0.65; 95% CI, −2.86 to 1.56 [P=0.56]) and over 3‐ to 12‐month PAQ summary scores (mean difference, −1.59; 95% CI, −4.06 to 0.88 [P=0.21]) was no longer significant. Twelve‐month health status gains following revascularization were similar in both groups (P=0.69). Conclusions Patients with PAD with coexisting DM have poorer health status, mostly explained by the differences in their psychosocial and other comorbidity burden. Patients with PAD and DM versus those without DM experience similar health status benefits following PAD revascularization.
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- 2020
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27. Competencia en tiempos de crisis: reflexiones a partir del COVID-19
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Carlos Mena Labarthe and Jessica González González
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crisis ,pandemia ,COVID-19 ,política de competencia ,México ,Law in general. Comparative and uniform law. Jurisprudence ,K1-7720 ,Civil law ,K623-968 - Abstract
Las agencias de competencia se han enfrentado a un escenario inédito como consecuencia de la pandemia por COVID-19. A diferencia de otras crisis económicas, la emergencia sanitaria ha planteado también nuevas condiciones de organización social con un impacto directo en la aplicación de la política de competencia. Estas circunstancias extraordinarias han traído importantes consideraciones para el derecho y la política de competencia económica. En México, entre otras cuestiones, se ha confirmado la necesidad de fortalecer la interacción entre la autoridad de competencia y otros reguladores, así como de contar con mayor visibilidad sobre el tratamiento a los acuerdos de colaboración entre competidores. Esta experiencia, sin duda, representa una oportunidad para replantear cuestiones que tendrán un impacto en el crecimiento y desarrollo de la política de competencia y su aplicación.
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- 2020
28. Relationship Between Depressive Symptoms and Health Status in Peripheral Artery Disease: Role of Sex Differences
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Qurat‐ul‐ain Jelani, Carlos Mena‐Hurtado, Matthew Burg, Robert Soufer, Kensey Gosch, Philip G. Jones, John A. Spertus, Basmah Safdar, and Kim G. Smolderen
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depressive symptoms ,health status ,peripheral artery disease ,sex differences ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background The association of depressive symptoms with health status in peripheral artery disease (PAD) is understudied. No reports of differential impact on women have been described. Methods and Results The PORTRAIT (Patient‐Centered Outcomes Related to Treatment Practices in Peripheral Artery Disease Investigating Trajectories) registry enrolled 1243 patients from vascular specialty clinics with new or worsening PAD symptoms. Depressive symptoms were assessed at baseline and 3 months using the 8‐Item Patient Health Questionnaire (score ≥10 indicating clinically relevant depressive symptoms). Disease‐specific and generic health status were measured by Peripheral Artery Questionnaire and EQ‐5D Visual Analogue Scale at baseline and 3, 6, and 12 months. An adjusted general linear model for repeated measures was constructed for baseline and 3‐, 6‐, and 12‐month health status outcomes by depressive symptoms at baseline. Differences by sex were tested with interaction effects. The mean age was 67.6±9.4 years with 38% (n=470) women. More women than men (21.1% versus 12.9%; P
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- 2020
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29. Impacts of Physical Environment Perception on the Frailty Condition in Older People
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Carlos Mena, Yony Ormazabal, Eduardo Fuentes, and Iván Palomo
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frailty syndrome ,neighbourhood’s conditions ,spatial distribution ,older people ,Chile ,Geography (General) ,G1-922 - Abstract
Frailty increases the vulnerability of older people who commonly develop a syndrome leading to growing dependence and finally often death. Physical environment conditions may affect the severity of the syndrome positive or negatively. The main objective of this study was to analyse the conditions of different urban physical environments and their relationship with the frailty syndrome in older people. Geographic Information Systems (GIS) analyses were performed to detect global and local geographic clustering. Investigating 284 adults with ages from 60 to 74 years old from Talca City, Chile, we found spatial clustering of frailty conditions registered for older people, with hotspots of high and low values associated with areas of different urban infrastructures and socioeconomic levels into the city. The spatial identifications found should facilitate exploring the impact of mental health programmes in communities exposed to disasters like earthquakes, thereby improving their quality of life as well as reducing overall costs. Spatial correlation has a great potential for studying frailty conditions in older people with regard to better understanding the impact of environmental conditions on health.
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- 2020
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30. Adherence to Guideline‐Recommended Therapy—Including Supervised Exercise Therapy Referral—Across Peripheral Artery Disease Specialty Clinics: Insights From the International PORTRAIT Registry
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John T. Saxon, David M. Safley, Carlos Mena‐Hurtado, Jan Heyligers, Robert Fitridge, Mehdi Shishehbor, John A. Spertus, Kensey Gosch, Manesh R. Patel, and Kim G. Smolderen
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medical management ,peripheral artery disease ,quality of care ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Underuse of guideline‐recommended therapy in peripheral artery disease (PAD) in administrative and procedural databases has been described, but reports on medically managed patients and referral to supervised exercise therapy (SET) in PAD are lacking. We aimed to document the use of PAD guideline‐recommended therapy, including SET in patients with PAD symptoms consulting a specialty clinic across 3 countries. Methods and Results The 16‐center PORTRAIT (Patient‐Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) registry enrolled 1275 patients with new or an exacerbation of PAD symptoms (2011–2015). We prospectively documented antiplatelet medications, statins, smoking cessation counseling and/or therapy, and referral to SET: “2 quality measures” referred to the use of both statin and antiplatelet medications; “4 quality measures” to receiving all 4 measures. Median odds ratios were calculated to quantify treatment variation across sites. A total of 89% patients were on antiplatelets, 83% on statins, and 23% had been referred to SET. Of 455 current smokers, 342 (72%) patients received smoking cessation therapy/counseling. Overall, 77.2% of patients received “2 quality measures” and 19.7% “4 quality measures.” The median odds ratio for 2 quality measures was 2.13 (95% CI, 1.61–3.56; P
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- 2020
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31. Population and development in the Amazon: A longitudinal study of migrant settlers in the Northern Ecuadorian Amazon
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Samuel SELLERS, Richard BILSBORROW, Victoria SALINAS, and Carlos MENA
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family planning ,deforestation ,livelihoods ,migration ,Science (General) ,Q1-390 - Abstract
ABSTRACT This paper examines changes over time for a full generation of migrant settlers in the Northern Ecuadorian Amazon (NEA). Data were collected from a 2014 household survey covering a subsample of households surveyed previously in 1990 and 1999. We observed changes in demographic behavior, land use, forest cover, and living conditions. As the frontier develops, human fertility is continuing to decline with contraceptive prevalence rising. Meanwhile, out-migration from colonist households, largely to destinations within the region, persists. More households have secure land tenure than in 1999, and are better off as measured by possession of assets. There is continued growth in pasture, largely at the expense of forest. Farms still serve as an important livelihood source for families, though growing cities in the NEA are creating more non-agricultural economic opportunities. Our findings provide a snapshot of demographic, economic, land use, and livelihood changes occurring in the NEA during the past quarter century, providing useful information for policymakers seeking to balance economic and environmental goals in order to promote sustainable development as well as protect biodiversity.
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- 2017
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32. Unusual Inflammatory Tinea Infections: Majocchi’s Granuloma and Deep/Systemic Dermatophytosis
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Jade Castellanos, Andrea Guillén-Flórez, Adriana Valencia-Herrera, Mirna Toledo-Bahena, Erika Ramírez-Cortés, Sonia Toussaint-Caire, Carlos Mena-Cedillos, Marcela Salazar-García, and Alexandro Bonifaz
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inflammatory tinea ,Majocchi’s granuloma ,dermatophytic ,Hadida ,Biology (General) ,QH301-705.5 - Abstract
Purpose of review. Inflammatory tinea is an uncommon group of dermatophyte entities that predominantly cause fungal infection of the skin and hair. This review intends to present all of the available evidence regarding its epidemiology, etiopathogenesis, clinical features, and diagnostic methods as well as treatments recommended for various inflammatory tinea infections. This article provides a review of Majocchi’s granuloma and dermatophytic or Hadida’s disease. Recent findings. The new phylogenetic classification of dermatophytes includes nine genera, and those that affect humans are Trichophyton, Microsporum, Epidermophyton, and Nannizzia. Furthermore, molecular advancements have revealed impaired antifungal immune responses caused by inflammatory tinea, which are detailed in this article. Summary. The common denominator in these pathologies is the presence of impaired immune responses and, consequently, an impaired inflammatory response by the host. It is necessary to be familiar with these immunological characteristics in order to use the appropriate diagnostic methods and to provide adequate treatment.
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- 2021
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33. Spatial clustering of people with memories and responses six years after an earthquake in Cauquenes, Chile
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Marcelo Leiva-Bianchi, Carlos Mena, Yony Ormazábal, and Carlos Serrano
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Post-traumatic stress disorder ,Post-traumatic growth ,Earthquake ,Geographic Information Systems ,Getis-Ord Gi* ,Chile ,Geography (General) ,G1-922 - Abstract
The occurrence of earthquakes can cause psychiatric problems expressed as unpleasant and uncontrollable memories of the event termed post-traumatic stress disorder (PTSD). Mapping the location of people and identifying their exposure and reactions to an earthquake can be extremely valuable from a public, mental health point of view. The main objective of this study was to examine people with respect to PTSD and healthy post-traumatic growth (PTG) after an earthquake searching for expression of geographic clustering that could be useful for a better understanding of mental health conditions. Geographic information systems analyses were performed to detect global and local geographic clustering. Investigating 171 randomly selected adults from Cauquenes, Chile, we demonstrated spatially clustered variables related to PTSD and PTG in Cauquenes six years after an earthquake. Urban and peri-urban areas had clear differences (hotspots/coldspots). The spatial identifications found should facilitate exploring the impact of mental health programmes in communities exposed to disasters like earthquakes, thereby improving their quality of life as well as reducing overall costs.
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- 2019
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34. Antiplatelet therapy for tibial balloon angioplasty: A clinical perspective
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Costin N Ionescu, Sophia E Altin, and Carlos Mena-Hurtado
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Medicine (General) ,R5-920 - Abstract
Percutaneous transluminal tibial balloon angioplasty has an important role in the therapeutic approach of critical limb ischaemia. Despite a growing number of patients with critical limb ischaemia, there are no trials to guide the pharmacologic approach post intervention. Guidelines pertaining to the antiplatelet therapy post percutaneous transluminal tibial balloon angioplasty have not been developed. In addition, critical limb ischaemia patients have multiple comorbidities and a higher risk of bleeding. To examine the shortest duration of antiplatelet therapy post percutaneous transluminal tibial balloon angioplasty, we reviewed the preclinical data used to develop the standards for the current angioplasty technique.
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- 2019
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35. Caracterización socioeconómica de la producción agrícola de las familias que habitan la microcuenca Mamaniri, Altiplano Boliviano
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Marleny Quispe Quispe, Jaime Quispe, Carlos Mena Herrera, René Chipana Rivera, and Gladys J. Chipana Mendoza
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caracterización ,socioeconomía ,valor agregado neto ,microcuenca ,Agriculture (General) ,S1-972 ,Plant culture ,SB1-1110 - Abstract
En Bolivia existen 797780 unidades productivas agropecuarias, de las cuales 224908 corresponden al departamento de La Paz, de estas 121903 se hallan en la región altiplánica del departamento. La caracterización es la descripción de las características principales y múltiples interrelaciones de las organizaciones mientras que el estudio socioeconómico investiga aspectos sociales y económicos de un grupo poblacional. El objetivo del estudio es caracterizar socioeconómicamente la producción agrícola en la microcuenca Mamaniri, el trabajo se realizó en las zonas de Taruta y Huancayno de la comunidad de Pomasara situada en la microcuenca, municipio Ayo Ayo del departamento de La Paz. Se seleccionaron dos estudios de casos, aplicando la investigación participativa, esto permitió el acercamiento directo con las familias campesinas, asimismo, se desarrollaron entrevistas semiestructuradas a seis familias que habitan la zona de Huancayno y cuatro familias en la zona de Taruta con preguntas concernientes al idioma que habla, educación, organización social comunal, tenencia de tierra, producción agrícola familiar, mano de obra, características de la siembra y uso de la semilla, prácticas de conservación del suelo, plagas y enfermedades que afectan a los cultivos, recurso hídrico y manejo del agua para riego, cosecha, rendimiento, pérdidas en la producción agrícola y destino de la producción. Los resultados fueron validados en dos talleres participativos, en cuanto a la evaluación económica, se halló el valor agregado neto de la producción agrícola de las dos familias seleccionadas. En la microcuenca existen diversos sistemas de producción agropecuaria que brindan valor comercial a los agricultores, el manejo de los componentes de los sistemas lo realizan de manera tradicional; los principales cultivos son papa, haba y cebolla. El ingreso rural familiar varía dependiendo de la calidad y cantidad del producto ofertado, esto ocasiona diferencia entre las familias, hallándose un valor agregado neto de 6186.90 USD y 5309.74 USD para la familia Mamani Chino y Santos Alanoca respectivamente.
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- 2018
36. Perception of risk sources by chilean blueberry producers
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Germán Lobos, Berta Schnettler, Carlos Mena, Yony Ormazábal, Juan Carlos Cantillana, and Jorge Borrar Retamales
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Risk and uncertainty ,climatic events ,risk management ,Plant culture ,SB1-1110 - Abstract
Abstract The biological and environmental nature of the agricultural production implies that growers operate in an environment of greater risk as compared to other economic activities. This has implications on the manner in which the growers can manage the risks inherent to their activity, which depends on how they perceive the risks and on the degree of aversion to risk. The main objective of this study was to learn about the perception of the main sources of risk that blueberry growers face in the Maule Region, Chile. This Region has about 25% of the planted area of this species in Chile. We used information from questionnaires implemented in 124 fields which considered two independent groups of growers: 48 owners and 76 managers. A scale of Importance of the Sources of Risk (ISR) was used. It included 13 items that the interviewed had to rank according to their importance through a Likert-type scale of four levels. The exploratory analysis allowed to infer that the ISR scale had adequate levels of internal consistency (Cronbach´s alpha = 0.83). The results showed that the climatic events are perceived by the growers as the main source of risk for blueberry production in Chile. The analysis also showed that the price of the product and the currency exchange rate are the next risks in importance for the field owners. On the other hand, the risks for the managers were, in decreasing order of importance: yield, product price, variability in sales, and volumes for sale. The knowledge of the perception of risk by the growers is a fundamental input for designing instruments of agricultural policies, risk management and support programs for the growers.
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- 2018
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37. Efecto de tres niveles de abono orgánico líquido aeróbico en la producción de espinaca (Spinacea oleracea L.) en el Centro Experimental Cota Cota
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Karen Eloiza Carrasco Nina, Eduardo Chilon Camacho, and Carlos Mena Herrera
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abono orgánico líquido aeróbico ,Spinacea oleracea L. ,variables agronómicas ,Agriculture (General) ,S1-972 ,Plant culture ,SB1-1110 - Abstract
La producción de hortalizas en Bolivia es intensiva, con el uso de fertilizantes químicos contaminando el suelo, agua y la salud humana ante este problema surge como alternativa la agricultura orgánica, el abono orgánico liquido aeróbico (AOLA), que mejora la fertilidad del suelo dando resistencia y vigor a los cultivos. Es por esta razón que el objetivo de la investigación fue evaluar el efecto de tres niveles de AOLA en la producción de espinaca en una carpa solar del Centro Experimental Cota Cota. Se evaluó el AOLA en dosis de 0, 10, 20 y 30% bajo un diseño completamente al azar, las variables evaluadas fueron porcentaje de emergencia, número de hojas, longitud de la hoja, ancho de la hoja, altura de la planta y peso de la biomasa. El porcentaje de emergencia fue de 85.71%. Para el número de hojas por planta, de las tres cosechas efectuadas, se observó que el T2 presentó el promedio más alto en la tercera cosecha con 13.33 hojas, en las otras cosechas la tendencia fue similar. En cuanto a la longitud de la hoja, de las tres cosechas realizadas, el promedio más alto fue para el T2 con 19 cm. El ancho de la hoja fue mayor con 15.67 cm para el T2 en la tercera cosecha, en la altura de la planta, el T2 obtuvo el más alto promedio en la tercera cosecha con 30.33 cm. Para la variable del peso de biomasa por planta, el mayor promedio fue del T2 con 56 g en la primera cosecha. En conclusión, se deduce que el nivel de AOLA más eficiente y que mayor respuesta frente a las variables fue con la concentración del 20% aplicado en el T2.
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- 2018
38. Spatial analysis for the epidemiological study of cardiovascular diseases: A systematic literature search
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Carlos Mena, Cesar Sepúlveda, Eduardo Fuentes, Yony Ormazábal, and Iván Palomo
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Spatial analysis ,Cluster ,Cardiovascular diseases. ,Geography (General) ,G1-922 - Abstract
Cardiovascular diseases (CVDs) are the primary cause of death and disability in de world, and the detection of populations at risk as well as localization of vulnerable areas is essential for adequate epidemiological management. Techniques developed for spatial analysis, among them geographical information systems and spatial statistics, such as cluster detection and spatial correlation, are useful for the study of the distribution of the CVDs. These techniques, enabling recognition of events at different geographical levels of study (e.g., rural, deprived neighbourhoods, etc.), make it possible to relate CVDs to factors present in the immediate environment. The systemic literature presented here shows that this group of diseases is clustered with regard to incidence, mortality and hospitalization as well as obesity, smoking, increased glycated haemoglobin levels, hypertension physical activity and age. In addition, acquired variables such as income, residency (rural or urban) and education, contribute to CVD clustering. Both local cluster detection and spatial regression techniques give statistical weight to the findings providing valuable information that can influence response mechanisms in the health services by indicating locations in need of intervention and assignment of available resources.
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- 2018
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39. Enfermedad de Castleman multicéntrica caracterizada por hiperinmunoglobulinemia policlonal y pénfigo paraneoplásico
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Martha Avilés-Robles, Samuel Roberts-Vega, Bertha Lilia Romero-Baizabal, Elisa Dorantes-Acosta, Carlos Mena-Cedillos, and Mario Perezpeña-Diazconti
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Pediatrics ,RJ1-570 ,Public aspects of medicine ,RA1-1270 - Published
- 2015
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40. Impact of walkability with regard to physical activity in the prevention of diabetes
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Carlos Mena, César Sepúlveda, Yony Ormazábal, Eduardo Fuentes, and Iván Palomo
- Subjects
Walkability ,GIS ,Physical activity ,Diabetes ,Connectivity ,Geography (General) ,G1-922 - Abstract
Walkability, a component of urban design intended to facilitate pedestrian traffic, depends on parameters associated with the connectivity of routes, population density and availability of destinations in the neighbourhood. The aim is to achieve levels of physical activity related to the prevention of risk factors associated with diseases, such as diabetes and the improvement of glycaemia control. It is important to consider that the effects of walkability depend on its relation with other variables present in the neighbourhood, e.g., environmental and socioeconomic factors. Considering this, improving walkability levels could be an effective strategy to reduce disease, the prevalence of diabetes in particular, in the population and thus reduce public spending. To investigate these relationships, PUBMED and ScienceDirect databases were searched using the following key words: Diabetes, Walkability and Physical activity.
- Published
- 2017
- Full Text
- View/download PDF
41. Geographic clustering of elderly people with above-norm anthropometric measurements and blood chemistry
- Author
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Carlos Mena, Eduardo Fuentes, Yony Ormazábal, and Iván Palomo
- Subjects
Geographic information system ,Moran’s I ,Getis-Ord Gi* ,Aging ,Cardiovascular parameters ,Geography (General) ,G1-922 - Abstract
The global percentage of people over 60 is strongly increasing and estimated to exceed 20% by 20,150, which means that there will be an increase in many pathological conditions related to aging. Mapping of the location of aging people and identification of their needs can be extremely valuable from a social-economic point of view. Participants in this study were 148 randomly selected adults from Talca City, Chile aged 60-74 at baseline. Geographic information systems (GIS) analyses were performed using ArcGIS software through its module Spatial Autocorrelation. In this study, we demonstrated that elderly people show geographic clustering according to above-norm results of anthropometric measurements and blood chemistry. The spatial identifications found would facilitate exploring the impact of treatment programmes in communities where many aging people live, thereby improving their quality of life as well as reducing overall costs.
- Published
- 2017
- Full Text
- View/download PDF
42. CHARACTERIZATION AND QUANTIFICATION OF NATIVE FOREST PATCHES IN A SECTOR OF THE SEMI-ARID LANDSCAPE AT THE MAULE’S REGION, CHILE
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Yony Ormazábal, Carlos Ávila, Carlos Mena, Yohana Morales, and Óscar Bustos
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fragmentación ,métricas de paisaje ,SIG ,RCEN ,Agriculture ,Forestry ,SD1-669.5 - Abstract
http://dx.doi.org/10.5902/1980509810556In general, the Mediterranean forests have suffered high levels of fragmentation, mainly by anthropogenic action, as result of the productive activities of agriculture and livestock, human settlements and forest plantations of fast growing exotic species, leading to loss of continuity of natural forests, and thus a decrease of biodiversity. In this context, the objective of this study was to evaluate the potential use of satellite images and Geographic Information Systems (GIS) to quantify and characterize the spatial evolution of native forests in a semi-arid landscape area at the Region of Maule, Chile. The study was conducted with Landsat-5 TM images of 2004 and 2008, which were classified by the supervised method where it was previously necessary to apply the atmospheric and the geometric corrections to reduce errors of interpretation and measurement. Within the analysis, it was incorporated digital thematic information of land use of the National Forestry Corporation (CONAF) and also it was joined one of the latest techniques derived from remote sensing for studying changes in land cover, that is called Radiometric Rotation Controlled by No-Change Axis (RCNA). Finally, the fragmentation indexes were estimated for characterizing the spatial configuration of landscape. From the results of the digital classification it was possible to estimate landscape metrics that show significant differences in the structure of the study area between the two periods. In addition, it was generated an image of change 2004/2008 that allowed to evaluate the consistency of the RCEN technique, demonstrating the feasibility of using this alternative methodology for the detection of changes in terms of degradation and recovery of woodlands.
- Published
- 2013
- Full Text
- View/download PDF
43. CARACTERIZACIÓN Y CUANTIFICACIÓN DE FRAGMENTOS DE BOSQUE NATIVO, EN UN SECTOR DEL SECANO INTERIOR DE LA REGIÓN DEL MAULE, CHILE
- Author
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Yony Ormazábal, Carlos Ávila, Carlos Mena, Yohana Morales, and Óscar Bustos
- Subjects
Agriculture ,Forestry ,SD1-669.5 - Abstract
In general, the Mediterranean forests have suffered high levels of fragmentation, mainly by anthropogenic action, as result of the productive activities of agriculture and livestock, human settlements and forest plantations of fast growing exotic species, leading to loss of continuity of natural forests, and thus a decrease of biodiversity. In this context, the objective of this study was to evaluate the potential use of satellite images and Geographic Information Systems (GIS) to quantify and characterize the spatial evolution of native forests in a semi-arid landscape area at the Region of Maule, Chile. The study was conducted with Landsat-5 TM images of 2004 and 2008, which were classified by the supervised method where it was previously necessary to apply the atmospheric and the geometric corrections to reduce errors of interpretation and measurement. Within the analysis, it was incorporated digital thematic information of land use of the National Forestry Corporation (CONAF) and also it was joined one of the latest techniques derived from remote sensing for studying changes in land cover, that is called Radiometric Rotation Controlled by No-Change Axis (RCNA). Finally, the fragmentation indexes were estimated for characterizing the spatial configuration of landscape. From the results of the digital classification it was possible to estimate landscape metrics that show significant differences in the structure of the study area between the two periods. In addition, it was generated an image of change 2004/2008 that allowed to evaluate the consistency of the RCEN technique, demonstrating the feasibility of using this alternative methodology for the detection of changes in terms of degradation and recovery of woodlands.
- Published
- 2013
44. GREEN AREA AND VEGETATION COVER INDEXES FOR PARRAL CITY (CHILE) USING PHOTOINTERPRETATION AND GIS
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Carlos Mena, Yony Ormazábal, Yohana Morales, Rómulo Santelices, and John Gajardo
- Subjects
área verde urbana ,accesibilidad ,Teledetección ,SIG ,Agriculture ,Forestry ,SD1-669.5 - Abstract
The importance of the green areas is increasing since they are an important factor in the health and welfare of urban population. Therefore, in Parral city, in Central Chile, it was quantified and analyzed the availability of green areas and vegetation cover, using aerial photographs scale 1:10000 and Geographic Information Systems (GIS). In a first stage, urban street trees were quantified through a simple random sample of twenty-four units with field measurements combined with measurements on aerial photographs, from which it was obtained the surface provided. Subsequently, through the creation of GIS layers, the surface of existing green areas and available open spaces were obtained. In addition, through supervised digital classification, the surface covered by urban forestry in private spaces was calculated. Quantity indexes show that Parral city currently has 12.72 ha of green areas, equivalent to 4.82 m2/hab, which implies a green area frequency of 0.022 m2/m2. These values could be improved, if the available open space are incorporated and thereby reach 12.06 m2 per inhabitant. In relation with availability indexes it was established that the average of accessibility to a green area is 327.2 m. Moreover, assuming a buffer of 200 m around the green areas, it was determined that there are 5160 houses with the basic service (56.4%). By incorporating the available open spaces, these values decrease significantly obtaining an average of accessibility to a green area of 213.7 m and coverage of basic service of 79.2%. Finally, it was estimated that the existing vegetation within the urban blocks (urban forest in private spaces) represents an important resource 17.8 times larger than urban street trees, so it should be considered within the municipal plans and policies.
- Published
- 2011
- Full Text
- View/download PDF
45. Índices de área verde y cobertura vegetal para la ciudad de Parral (Chile), mediante fotointerpretación y SIG
- Author
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Carlos Mena, Yony Ormazábal, Yohana Morales, Rómulo Santelices, and John Gajardo
- Subjects
Agriculture ,Forestry ,SD1-669.5 - Abstract
The importance of the green areas is increasing since they are an important factor in the health and welfare of urban population. Therefore, in Parral city, in Central Chile, it was quantified and analyzed the availability of green areas and vegetation cover, using aerial photographs scale 1:10000 and Geographic Information Systems (GIS). In a first stage, urban street trees were quantified through a simple random sample of twentyfour units with field measurements combined with measurements on aerial photographs, from which it was obtained the surface provided. Subsequently, through the creation of GIS layers, the surface of existing green areas and available open spaces were obtained. In addition, through supervised digital classification, the surface covered by urban forestry in private spaces was calculated. Quantity indexes show that Parral city currently has 12.72 ha of green areas, equivalent to 4.82 m2/hab, which implies a green area frequency of 0.022 m2/m2. These values could be improved, if the available open space are incorporated and thereby reach 12.06 m2 per inhabitant. In relation with availability indexes it was established that the average of accessibility to a green area is 327.2 m. Moreover, assuming a buffer of 200 m around the green areas, it was determined that there are 5160 houses with the basic service (56.4%). By incorporating the available open spaces, these values decrease significantly obtaining an average of accessibility to a green area of 213.7 m and coverage of basic service of 79.2%. Finally, it was estimated that the existing vegetation within the urban blocks (urban forest in private spaces) represents an important resource 17.8 times larger than urban street trees, so it should be considered within the municipal plans and policies.
- Published
- 2011
46. Drift Correction of Lightweight Microbolometer Thermal Sensors On-Board Unmanned Aerial Vehicles
- Author
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Francisco-Javier Mesas-Carrascosa, Fernando Pérez-Porras, Jose Emilio Meroño de Larriva, Carlos Mena Frau, Francisco Agüera-Vega, Fernando Carvajal-Ramírez, Patricio Martínez-Carricondo, and Alfonso García-Ferrer
- Subjects
UAV ,uncooled thermal sensor ,precision agriculture ,thermal orthomosaic ,Science - Abstract
The development of lightweight sensors compatible with mini unmanned aerial vehicles (UAVs) has expanded the agronomical applications of remote sensing. Of particular interest in this paper are thermal sensors based on lightweight microbolometer technology. These are mainly used to assess crop water stress with thermal images where an accuracy greater than 1 °C is necessary. However, these sensors lack precise temperature control, resulting in thermal drift during image acquisition that requires correction. Currently, there are several strategies to manage thermal drift effect. However, these strategies reduce useful flight time over crops due to the additional in-flight calibration operations. This study presents a drift correction methodology for microbolometer sensors based on redundant information from multiple overlapping images. An empirical study was performed in an orchard of high-density hedgerow olive trees with flights at different times of the day. Six mathematical drift correction models were developed and assessed to explain and correct drift effect on thermal images. Using the proposed methodology, the resulting thermally corrected orthomosaics yielded a rate of error lower than 1° C compared to those where no drift correction was applied.
- Published
- 2018
- Full Text
- View/download PDF
47. Detección y cuantifi cación de área quemada por incendios forestales utilizando geomática / Detection and quantifi cation of burnt area by forest fi res utilizing Geomatics
- Author
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John Gajardo Valenzuela, Carlos Mena Frau, Yony Ormazábal Rojas, and Yohana Morales Hernandéz
- Subjects
incendios forestales ,área quemada ,índices espectrales ,segmentación. ,Environmental sciences ,GE1-350 - Abstract
La Corporación Nacional Forestal (CONAF) es la entidad a nivel nacional,encargada de proteger los ecosistemas forestales de los agentes y procesosdañinos como la desertifi cación, el fuego y otras formas de deterioro. En Chile la mayoría de los incendios forestales son producidos por el hombre, generando un daño promedio anual de 50.000 hectáreas. Aunquela mayoría de los incendios producidos no sobrepasa las 10 hectáreas, surge la necesidad de contar con estadísticas fi ables y cuantifi car deforma adecuada los grandes siniestros que se producen en zonas con poca o nula accesibilidad. En este contexto, el uso de datos provenientes de plataformas satelitales (NOAA-AVHRR, TERRA/AQUA-MODIS) ha mostrado ya su utilidad en el estudio de estos fenómenos a escala regional. En este trabajo se ha estudiado la aplicación de imágenes de dos sensores ETM+ y ASTER para la evaluación de índices espectrales y algoritmos de crecimiento de regiones con el objetivo de discriminar y cartografi ar un incendio ocurrido en la cordillera de la Región del Maule,Chile. Los resultados indican que el uso de un algoritmo de crecimiento de regiones, mostró los mejores resultados (Fiabilidad = 97%, Kappa = 80.6%) por sobre las segmentaciones de los índices NDVI, BAI y NBR. Aunque los resultados son auspiciosos, se presentaron algunos inconvenientes relacionados a la correcta delimitación e inclusión de la totalidad de la zona quemada, lo anterior puede ser mejorado trabajando con imágenes de mayor resolución espacial, cuya data sea más reciente a la fecha del incendio y eliminado algunas fuentes de confusión como el sombreado topográfico.
- Published
- 2008
48. EXACTITUD ESPACIAL EN LA CREACIÓN DE BASES DE DATOS SIG MODELOS RÁSTER Y VECTORIAL SPATIAL ACCURACY IN THE CREATION OF DATABASES GIS RASTER AND VECTOR MODELS
- Author
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Carlos Mena Frau, Yony Ormazábal Rojas, Yohana Morales Hernández, and John Gajardo Valenzuela
- Subjects
Representación geográfica ,exactitud espacial ,modelo vectorial ,modelo ráster ,base de datos ,Geographic representation ,spatial accuracy ,vector model ,raster model ,database ,Mechanical engineering and machinery ,TJ1-1570 ,Industrial engineering. Management engineering ,T55.4-60.8 - Abstract
La exactitud en la representación espacial de elementos geográficos en una base de datos de un Sistema de Información Geográfica (SIG) está sujeta a errores originados en los procesos de captura y procesamiento de los datos, lo cual queda en evidencia cuando se integra información más exacta. La cuantificación del error es fundamental cuando se pretende tomar decisiones sobre la base de la información disponible. En el estudio se establece una metodología para determinar y comparar el error de representación de elementos geográficos en los modelos vectorial y ráster. La base de datos incluye elementos puntuales, lineales y poligonales, que representan elementos reales correspondientes a una torre, un camino y un rodal. Esta información se obtuvo a partir de mediciones en terreno con el Sistema de Posicionamiento Global (GPS), que fueron procesadas para dar origen a coberturas en formato vectorial. Posteriormente, se realizó el traspaso de la información al formato ráster, empleando resoluciones de píxel de 5, 10 y 20 metros. Mediante un algoritmo matemático se determinaron coordenadas homólogas entre los elementos representados en los dos modelos. De la distancia euclidiana entre coordenadas homólogas, se obtuvo un error medio de representación para cada modelo que luego se utilizó para hacer un análisis estadístico de comparación de exactitud espacial entre los modelos. Los resultados obtenidos indican que no existen diferencias significativas en el error medio de los modelos vectorial y ráster, pero sí existen diferencias en los errores medios arrojados para las distintas resoluciones empleadas en la rasterización de la información original.Representation spatial accuracy of geographic elements in a Geographic Information System (GIS) database is subject to errors generated in the processes of data capture and processing, which is in evidence when more exact information is integrated. Error quantification is fundamental when the decision-making is based on the information available. The study establishes a methodology to determine and compare the representation error of geographic elements in the vector and raster models. Database includes point, line and polygon elements that represent real objects which are a tower, a road and a parcel. This information was obtained from land measurements with Global Positioning System (GPS) that were processed to obtain vector layers. Later, the convert of vectors layers into raster layers was made using pixel resolutions of 5, 10 and 20 meters. By means of a mathematical algorithm homologous coordinates between the elements represented in both models were determined. From the euclidean distance between homologous coordinates, a mean error of representation for each model was obtained that soon was used to make a statistical comparison analysis of space accuracy between models. The obtained results indicate that there are not significant differences between mean errors of vector and raster models, but there are differences between mean errors of the raster layers at different resolutions.
- Published
- 2008
49. Teledetección y Sig en el Ámbito Forestal: Experiencias en Chile Remote Sensing and Gis in Forestry: Experiences in Chile
- Author
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Carlos Mena Frau, John Gajardo Valenzuela, Yony Ormazábal Rojas, Yohana Morales Hernádez, and Rodrigo Montecinos Guajardo
- Subjects
teledetección ,sistema de información geográfica ,planificación florestal. ,Environmental sciences ,GE1-350 - Abstract
La Teledetección espacial y los Sistemas de Información Geográfica (SIG) han constituido una verdadera revolución tecnológica y metodológica para efectuar la adquisición, manejo y análisis de la información geográfica sólo comparable con el efecto que provocó la invención del mapa. De hecho, estas nuevas tecnologías constituyen el eje vertebrado que sustenta los sistemas de consulta y análisis utilizados en las empresas forestales, soportando grandes volúmenes de información cartográfica relevante para el proceso de toma de decisiones. Por consiguiente, la integración de éstas disciplinas geomáticas generan y suministran información temática y espacial, de carácter primario o secundario, para efectuar una adecuada planificación de las actividades ha llevar a cabo durante toda la extensión del ciclo económico forestal, manifestadas en los horizontes de planificación estratégico, táctico y operacional. En el presente artículo se sintetizan algunas experiencias desarrolladas en Chile y particularmente en la Facultad de Ciencias Forestales y el Centro de Geomática de la Universidad de Talca, en lo referido a la utilización de Teledetección y SIG en el ámbito forestal.AbstractThe Remote Sensing and the Geographic Information Systems (GIS) haveconstituted a really technological and methodological revolution to make the acquisition, processing and analysis of geographic information only comparable with the effect that the invention of the map provoked. In fact, these new technologies constitute the vertebrate axle that sustains to the consultation and analysis systems utilized at the forest companies, storing big volumes of relevant cartographic information for the process of take of decisions. Consequently, the integration of these geomatic disciplines generate and supply primary or secondary thematic and space information, in order to make an adequate planning of the activities that will take effect during the extension of the forest business cycle, manifested in the strategic, tactical and operational horizons of planning. The present article synthesizes some experiences developed at Chile andparticularly in the Faculty of Forest Sciences and the Geomatic Center of the University of Talca, referred to the utilization of Remote Sensing and GIS in forest activities.
- Published
- 2006
50. Comportamiento del aborto séptico en pacientes que consultaron al Hospital San Vicente de Paúl. Universidad de Antioquia 1994-1997
- Author
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Carlos Mena, José I. Gutiérrez, Wilson Múnera, Rubén Petro, Fabio Pineda, Orlando Restrepo, and William Botero
- Subjects
Gynecology and obstetrics ,RG1-991 - Abstract
El aborto séptico constituye en la actualidad un problema médico, social y económico a nivel mundial debido a la gran demanda de casos, los elevados costos y las tasas de morbimortalidad materna. La Federación Internacional de Planificación Familiar calcula que cada año ocurren 5 millones de abortos inducidos; igualmente, en un estudio realizado en Colombia en 1990 se informaron 4.930 abortos en un período de 6 meses. El presente estudio es de tipo descriptivo retrospectivo, de corte transversal, llevado a cabo en el Departamento de Ginecología y Obstetricia del Hospital San Vicente de Paúl (HSVP)- Universidad de Antioquia, entre el 1º de octubre de 1997 y el 10 de marzo de 1998; en él se tuvieron en cuenta todas las pacientes que consultaron al HSVP entre el 1º de enero de 1994 y el 31 de diciembre de 1997. Se encontró que el grupo de edad más afectado fue el comprendido entre los 16-25 años, correspondiendo la mayor población a solteras y amas de casa. La gran mayoría de las pacientes eran multigestantes y la principal complicación fue el shock séptico.
- Published
- 1999
- Full Text
- View/download PDF
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