Sebastian Sanchez - Academia.edu (original) (raw)
Papers by Sebastian Sanchez
22nd SGEM International Multidisciplinary Scientific GeoConference Proceedings 2022, Nano, Bio, Green and Space � Technologies For a Sustainable Future, VOL 22, ISSUE 6.2
Conventional wastewater treatment plants (CWWTPs) play a key role in reducing the environmental i... more Conventional wastewater treatment plants (CWWTPs) play a key role in reducing the environmental impact of urban wastewater. But nowadays, this role goes even further with climate change, water scarcity, and the current energy crisis. After the thickening of the secondary sludge, a wastewater flow is generated, which is normally recirculated to the plant head for further treatment. This work aims to use secondary thickener wastewater (STW) as a culture medium for Chlorella vulgaris, Neochloris oleoabundans and Scenedesmus quadricauda growth. These microalgae have the capacity to remove organic and inorganic matters, particularly, in wastewater rich in nitrogen and phosphate compounds. The experiments have been carried out in stirred photobioreactors with 1 L capacity under the following common operating conditions pH 8, mechanical agitation = 200 rpm, air supply rate = 0.5 L/min, continuous artificial illumination intensity = 359 ?E m-2 s-1, and non-sterilized conditions. The net bio...
American Journal of Gastroenterology
Automation
A rimless wheel or a wheel without a rim, is the simplest example of a legged robot and is an ide... more A rimless wheel or a wheel without a rim, is the simplest example of a legged robot and is an ideal testbed to understand the mechanics of locomotion. This paper presents the design, modeling, and control of a differential drive rimless wheel robot that achieves straight-line movement and turning. The robot design comprises a central axis with two 10-spoked springy rimless wheels on either side and a central body that houses the electronics, motors, transmission, computers, and batteries. To move straight, both motors are commanded to constant pitch control of the central body. To turn while maintaining constant pitch, a differential current is added and subtracted from currents on either motor. In separate tests, the robot achieved the maximum speed of 4.3 m per sec (9.66 miles per hour), the lowest total cost of transport (power per unit weight per unit velocity) of 0.13, and a smallest turning radius of 0.5 m. A kinematics-based model for steering and a dynamics-based sagittal (f...
Cancer Epidemiology, Biomarkers & Prevention, 2021
Purpose: In sub-Saharan Africa, cancer treatment facilities are often scarce and centered in urba... more Purpose: In sub-Saharan Africa, cancer treatment facilities are often scarce and centered in urban areas, which means many patients must travel long distances to reach cancer care. Still, little is known about how this distribution of cancer centers impacts patients' ability to access care. Methods: Records of all pediatric patients (<18yo) treated for cancer in Tanzania in 2019 through the Tanzanian Pediatric Cancer Network were reviewed. This network represents all 9 hospitals currently treating children with cancer in Tanzania. Demographic and diagnostic information was recorded. ArcGIS was used to estimate patients' travel times from home addresses to cancer care. AccessMod was used to calculate 4-hour access for the population. Results: In 2019, a total of 821 pediatric patients were diagnosed with cancer with an incidence of 1.42/100,000 population. The most common diagnoses were Wilms tumor (17.2%, n=134), retinoblastoma (16.8%, n=131), and acute lymphoblastic leuk...
We present the relation between the star formation rate density, Ssfr, and the hydrostatic mid-pl... more We present the relation between the star formation rate density, Ssfr, and the hydrostatic mid-plane pressure, Phyd, for 4260 star-forming regions of kpc size located in 96 galaxies included in the EDGE-CALIFA survey. We find that these two parameters are tightly correlated, exhibiting a smaller scatter and a stronger correlation in comparison to other star-forming scaling relation. A power-law, with a slightly sub-linear exponent, is a good representation of this relation. Our analysis suggests that the primary channel of self regulation of the Ssfr at kpc scales comes from momentum flux injection to the interstellar medium from supernovae explosions. However, other channels of pressure in disk galaxies may also play a significant role in shaping the Ssfr at local scales. Our results also suggest that Phyd can be consider as the main driver of the star formation at kpc scales, rather than individual components of the baryonic mass.
2020 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), 2020
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Stroke: Vascular and Interventional Neurology, 2021
Introduction : Aneurysm wall enhancement using high‐resolution vessel wall imaging (HR‐VWI) may p... more Introduction : Aneurysm wall enhancement using high‐resolution vessel wall imaging (HR‐VWI) may provide new surrogate biomarkers for instability. Finite element analysis (FEA) paired with HR‐VWI can provide more insight into complex morphological features that ultimately lead to aneurysm growth and rupture. Methods : Unruptured intracranial aneurysms were reconstructed in 3D from CE‐MRA imaging. Shells were created assuming a uniform wall thickness of 86 μm and FEA was conducted with a 3rd order polynomial material model, assuming the wall to be isotropic, homogenous, and similar between subjects. The 95th percentile wall tension was defined as high wall tension to account for mesh artifacts. Low wall tension was identified from nodal values and verified on contour plots. Regions of high and low wall tension were characterized from contour plots. Aneurysms were measured and classified as enhancing (CR stalk ≥0.6) or non‐enhancing (CR stalk <0.6), using manual ROI measurements fro...
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET systems with a geometry different from a closed ring, the Time of Flight (TOF) of the anni... more In PET systems with a geometry different from a closed ring, the Time of Flight (TOF) of the annihilation photons appears to be relevant. Such a system capability helps to compensate the missing angular information that generates artifacts on the reconstructed images. In this work, two ASIC designs are evaluated for their use in PET systems having accurate coincidence resolving times (CRT) while preserving both energy and spatial resolutions. One of the ASIC options is the TOFPET1 from PETsys and the other the so-called PETIROC2 from Weeroc. Detection blocks based on scintillation LYSO crystal arrays have been used to first optimize the experiments. Parameters such as spatial, energy and time resolution have been obtained. Promising CRT results were found nearing 350 ps FWHM for a pair of photosensor channels (PETsys) and roughly 800 ps for all 16 against 16 channels (Weeroc). In terms of spatial resolution, 2 mm pixels size are well resolved with energy values approaching 15% have preliminary been measured for both ASICs. With the TOFPET1 ASIC, also tests with monolithic crystals were carried out. Those showed the system to provide depth of interaction (DOI) information. A DOI resolution (FWHM) of about 3 mm was preliminary estimated in a 25×25×10 mm3 LYSO scintillator. A calibration process for time alignment of the signal paths was carried out to provide accurate CRT results. The time walk error between channels was also compensated. Several methods for the timestamp averaging have been tried, resulting on preliminary CRT values in the 1 ns FWHM range.
Current Research Journal of Biological Sciences, 2019
Keeping in mind the relationship between the basal metabolic rate and the change in weight in the... more Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to generate a model of the same. As a result of data transformation, we obtained a graphic representation that is consistent with the original data. This representation manifested that after puberty, the parameter space loses its initial planarity. Thus, the model helps to sustain that the geometric phase changes that occur when the parameter space undergoes a gradual curvature, can contribute to explaining the biological aging process.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET detectors based in monolithic scintillators the interaction coordinates of each photon imp... more In PET detectors based in monolithic scintillators the interaction coordinates of each photon impact, in particular the 511 keV energy, can be determined from the light distribution sampled at the photosensors pixels. However, some of these distributions can be produced by pure dark noise from the SiPM photosensor, multi-interaction events with long travelled distance, pile-up, etc. Early rejection of these events can improve the SNR of the detector block and, as a result, in the also in reconstructed PET image. Moreover, this early rejection can reduce the statistics necessary to reconstruct those images preserving the SNR. To perform the rejection of noisy distributions, a comparison between a theoretical light distribution and the measured one is made by means of the Pearson product-moment correlation coefficient. This coefficient provides a metric, with range [−1, 1], suitable for assessing the similarity between the two distributions and, thus, allowing the rejection of uncorre...
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
A series of small size 22Na point sources have been simulated using GATE, following the NEMA prot... more A series of small size 22Na point sources have been simulated using GATE, following the NEMA protocol, and applied to the geometry of a brain dedicated PET so-called MindView. The simulated scanner geometry is currently composed by one ring of 20 detector blocks with a distance of about 330 mm between opposite detectors. Each detector module includes a monolithic LYSO crystal of 50 × 50 × 20 mm3 and a custom 12 × 12 SiPM array (TSV-type, SensL). The system defines an axial and trans-axial fields of view (FoV) of about 46 mm and 240 mm, respectively. The scintillation light inside the monolithic block was simulated in GEANT4 and is sampled following the readout scheme providing information on each SiPM array row and column (12 + 12). Out of this, three different approaches for the determination of the impact coordinates within the monolithic crystals have been considered. A first approach makes use of the center of gravity (CoG) calculation for the planar XY coordinates but the photo...
2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2017
The aim of this work is to show the potential capabilities of monolithic-based LYSO crystals, cou... more The aim of this work is to show the potential capabilities of monolithic-based LYSO crystals, coupled to large SiPM arrays to be considered as detector blocks for TOF-PET scanners. An ASIC read-out with accurate timing capabilities is used to independently process each SIPM element. Several studies have been carried out using both crystal arrays and monolithic blocks showing an overall good performance. The most relevant parameters evaluated in this work are: spatial, energy and time resolutions. We obtained coincidence resolving times as good as 340 ps FWHM for one to one coupling in crystal arrays and 1.2 ns FWHM using a monolithic block in coincidence with a 1 pixel reference detector.
Panamerican Journal of Trauma, Critical Care & Emergency Surgery, 2020
Introduction: Emergency pancreatoduodenectomy is a procedure that is indicated for the management... more Introduction: Emergency pancreatoduodenectomy is a procedure that is indicated for the management of severe pancreaticoduodenal trauma after damage control surgery. Objectives: To present our experience of pancreaticoduodenal trauma management with emergency pancreatoduodenectomy and damage control surgery. Materials and methods: Retrospectively recorded data of patients with severe pancreaticoduodenal trauma who underwent a pancreatoduodenectomy and damage control for trauma at a high-volume trauma center. Results: In a period of 6 years, four patients (three men and one woman, median age 17.5 years, range: 16-21 years) with severe pancreaticoduodenal trauma underwent a pancreatoduodenectomy and damage control procedure (gunshot n = 4), and in a second surgical procedure underwent gastrointestinal tract reconstruction. In total, 75% incidence of surgical site infection (SSI) was reported, 25% healthcare-associated pneumonia, and 50% postoperative pancreatic fistula (POPF). Intensive care unit (ICU) of 12.25 and hospital stay of 29.5 days mean and no mortality. Conclusion: An emergency pancreatoduodenectomy can be a lifesaving procedure in patients with non-reconstructable duodenopancreatic injuries. Damage control surgery in pancreaticoduodenal trauma is an alternative for management although with high risk of morbidity.
Liver Research, Disorders & Therapy, 2018
Introduction: A Bezoar is defined as a non-digestible foreign body trapped inside the digestive t... more Introduction: A Bezoar is defined as a non-digestible foreign body trapped inside the digestive tract usually ingested intentionally or accidentally. In 1779 Baudamant published the first case report of a bezoar in a human patient. Case report: We present a case of a patient in which a plastic bezoar, a toothbrush, was found as the etiologic factor of acute pancreatitis. We describe its management with laparoscopy and literature review. Discussion and conclusion: Although gastro-duodenal bezoars are rare, it is important to take them into account as a rare yet possible etiology of acute pancreatitis. A laparoscopic approach yields positive results in stable patients with no intestinal obstruction.
viii but not uniform in various parts of the world, leaving a gap in knowledge as to the proper r... more viii but not uniform in various parts of the world, leaving a gap in knowledge as to the proper response, and the mitigation of pitfalls needed. Objectives: Presenting and showing to the international community recent advances in hospital-and community-based interventions and violence prevention research from different regions of the world, performed in local contexts and framed in the new concepts of Global Violence Prevention.
Alzheimer's & Dementia, 2016
Revista Complutense de Educación, 2016
La organización y atención a la diversidad en centros de enseñanza secundaria de España........ 4... more La organización y atención a la diversidad en centros de enseñanza secundaria de España........ 4.1. La atención a la diversidad en el marco de la escuela inclusiva 4.2. La atención a la diversidad desde los Servicios psicopedagógicos 4.3. Proyectos, programas y planes para atender a la diversidad en los centros de educación secundaria 4.4. Procesos organizaqtivos implicados,condiciones y fases de los planes, programas y proyectos de atención a la diversidad 4.5. El camio hacia la inclusión en los centros de educación secundaria 4.6. Referencias bibliográficas Capítulo V La organización y atención a la diversidad en centros de enseñanza secundaria de México........ 5.1. Introducción 5.2. El Sistema educativo y la atención a la diversidad para menores entre 12 y 15 años de edad 5.3. Educación secundaria por televisión en México 5.4. ENLACE y el Programa para Mejorar el Logro Educativo 5.5. Conclusiones 5.6. Referencias bibliográficas Capítulo VI La organización y atención a la diversidad en centros de enseñanza secundaria de Nicaragua.... 6.1. Introducción 6.2. Políticas educativas relacionada con la atención a la diversidad en la Educación secundaria 6.3. Concepciones y prácticas sobre la atención a la diversidad en centros de educación secundaria 6.4. Comentarios y valoraciones de los resultados obtenidos 6.5. Referencias bibliográficas Capítulo VII La organización y atención a la diversidad en centros de educación media de Panamá............... 7.1. Introducción 7.2. La organización y atención a la diversidad en centros de educación media 7.3. La diversidad y los grupos vulnerabvles en las políticas educativas del país 7.4. La participación de los actores claves 7.5. Modelos y estrategias de atención a la diversidad y grupos vulnerables en los centros de educación media 7.6. La gestión en los centros de enseñanza que atienden la diversidad 7.7. Conclusiones 7.8. Referencias bibliográficas Capítulo VIII La organización y atención a la diversidad en centros de enseñanza secundaria de Paraguay..... 8.1. Legislación paraguaya 8.2. Atención a la diversidad 8.3. Educación inclusiva 8.4. Educación inclusiva y educación especial 8.5. Conclusiones 8.6. Referencias bibliográficas Capítulo IX La organización y atención a la diversidad en centros educativos de Perú.
Latin American Journal of Aquatic Research, 2016
RESUMEN. En la piscicultura el 30% de los nutrientes aportados son retenidos como biomasa animal ... more RESUMEN. En la piscicultura el 30% de los nutrientes aportados son retenidos como biomasa animal y el remanente se pierde en los sedimentos. Una alternativa es producir en policultivo, para aprovechar espacio y alimento. El objetivo del trabajo fue comparar y evaluar el crecimiento del sábalo Prochilodus lineatus en monocultivo, en contraste con policultivo de sábalo y pacú Piaractus mesopotamicus durante 11 meses. Se utilizaron cuatro tratamientos, control (sábalo 100/0), T1 (proporción sábalo-pacú 50/50), T2 (proporción sábalo-pacú 33/67), T3 (proporción sábalo-pacú 25/75); ubicados en estanques de tierra fertilizados. Se suministró diariamente alimento balanceado considerando el 5% de la biomasa. Se registraron parámetros de calidad de agua, además de realizarse biometrías mensuales. Los parámetros físicos y químicos de calidad de agua permanecieron dentro de valores adecuados para ambas especies en cada estanque. Las variables zootécnicas analizadas fueron: coeficiente de crecimiento específico, conversión alimenticia, productividad, supervivencia y peso vivo. La variable peso en T3 fue superior, diferenciándose significativamente del control (P < 0,05). Los valores de las otras variables fueron más altos que en los tratamientos restantes, pero sin diferencias significativas (P < 0,05). Si bien no se encontraron diferencias en cuatro de las cinco variables estudiadas, se observó una tendencia a favor de T3, la que pudo no ser estadísticamente significativa debido al escaso número de réplicas disponibles y a la alta variabilidad. Sin embargo, siguiendo la tendencia obtenida y bajo las condiciones experimentales, el sábalo presentó un mejor crecimiento y supervivencia cuando se encontró acompañado del pacú en una relación 25/75, constituyendo una alternativa satisfactoria para el cultivo de la especie. Palabras clave: cultivo semi-intensivo, factor de crecimiento específico, multiespecie, acuicultura.
Astronomische Nachrichten Supplement, Aug 1, 2004
Chemical Senses
A coated QCM static sensing system construction has been developed to analysis volatile organic c... more A coated QCM static sensing system construction has been developed to analysis volatile organic compounds frequently found in some positive and negative organoleptic olive oil attributes. The film-coated is composed by an adsorbent material onto a substrate which improves adherence and homogeneous distribution of adsorbent layer. Polyvinyl chloride (PVC) as substrate film and tetrahydrofuran (THF) as solvent have been used, analysing twelve PVC/ THF relations (0.25–50 mg/ml range) and seven dropped volumes (0.5–10 ml range). Sensor responses are measured as the stabilised oscillation frequency shift of the coated QCMsensor. PVC/THF = 1 relation and 10 ml dropped volume have been selected asQCMsubstrate film because they give the firmest sensor responses and constitute the greatest PVC film area. Operating parameters, such as measurement chamber temperature and sensor stabilisation time, have been optimised to improve the selectivity of the coated QCM sensor. After 15 minutes of sensor stabilisation time, volatile organic compounds, such as acetic acid, 1-octen-3-ol, 2-butanone, (Z)-3-hexenyl acetate, hexanal and undecane, are injected in a closed thermostat chamber, where coated QCM sensor is placed inside. OV–275 (1 mg) is used as adsorbent material. Changes in the oscillation frequency is registered each 5 seconds during 25 minutes. Measurement chamber temperature at 30 C. For acetic acid and (Z)-3-hexenyl acetate the highest frequency shifts are found at 30 C. 2-butanone, hexanal and 1-octen-3-ol exhibit great frequency shifts at 35 C, but there are low differences with oscillation frequency shifts at 30 C. The adsorption of undecane shows double frequency shift at 35 C than 30 C, but this nonpolar volatile does not interact with polar OV-275 polymer.
22nd SGEM International Multidisciplinary Scientific GeoConference Proceedings 2022, Nano, Bio, Green and Space � Technologies For a Sustainable Future, VOL 22, ISSUE 6.2
Conventional wastewater treatment plants (CWWTPs) play a key role in reducing the environmental i... more Conventional wastewater treatment plants (CWWTPs) play a key role in reducing the environmental impact of urban wastewater. But nowadays, this role goes even further with climate change, water scarcity, and the current energy crisis. After the thickening of the secondary sludge, a wastewater flow is generated, which is normally recirculated to the plant head for further treatment. This work aims to use secondary thickener wastewater (STW) as a culture medium for Chlorella vulgaris, Neochloris oleoabundans and Scenedesmus quadricauda growth. These microalgae have the capacity to remove organic and inorganic matters, particularly, in wastewater rich in nitrogen and phosphate compounds. The experiments have been carried out in stirred photobioreactors with 1 L capacity under the following common operating conditions pH 8, mechanical agitation = 200 rpm, air supply rate = 0.5 L/min, continuous artificial illumination intensity = 359 ?E m-2 s-1, and non-sterilized conditions. The net bio...
American Journal of Gastroenterology
Automation
A rimless wheel or a wheel without a rim, is the simplest example of a legged robot and is an ide... more A rimless wheel or a wheel without a rim, is the simplest example of a legged robot and is an ideal testbed to understand the mechanics of locomotion. This paper presents the design, modeling, and control of a differential drive rimless wheel robot that achieves straight-line movement and turning. The robot design comprises a central axis with two 10-spoked springy rimless wheels on either side and a central body that houses the electronics, motors, transmission, computers, and batteries. To move straight, both motors are commanded to constant pitch control of the central body. To turn while maintaining constant pitch, a differential current is added and subtracted from currents on either motor. In separate tests, the robot achieved the maximum speed of 4.3 m per sec (9.66 miles per hour), the lowest total cost of transport (power per unit weight per unit velocity) of 0.13, and a smallest turning radius of 0.5 m. A kinematics-based model for steering and a dynamics-based sagittal (f...
Cancer Epidemiology, Biomarkers & Prevention, 2021
Purpose: In sub-Saharan Africa, cancer treatment facilities are often scarce and centered in urba... more Purpose: In sub-Saharan Africa, cancer treatment facilities are often scarce and centered in urban areas, which means many patients must travel long distances to reach cancer care. Still, little is known about how this distribution of cancer centers impacts patients' ability to access care. Methods: Records of all pediatric patients (<18yo) treated for cancer in Tanzania in 2019 through the Tanzanian Pediatric Cancer Network were reviewed. This network represents all 9 hospitals currently treating children with cancer in Tanzania. Demographic and diagnostic information was recorded. ArcGIS was used to estimate patients' travel times from home addresses to cancer care. AccessMod was used to calculate 4-hour access for the population. Results: In 2019, a total of 821 pediatric patients were diagnosed with cancer with an incidence of 1.42/100,000 population. The most common diagnoses were Wilms tumor (17.2%, n=134), retinoblastoma (16.8%, n=131), and acute lymphoblastic leuk...
We present the relation between the star formation rate density, Ssfr, and the hydrostatic mid-pl... more We present the relation between the star formation rate density, Ssfr, and the hydrostatic mid-plane pressure, Phyd, for 4260 star-forming regions of kpc size located in 96 galaxies included in the EDGE-CALIFA survey. We find that these two parameters are tightly correlated, exhibiting a smaller scatter and a stronger correlation in comparison to other star-forming scaling relation. A power-law, with a slightly sub-linear exponent, is a good representation of this relation. Our analysis suggests that the primary channel of self regulation of the Ssfr at kpc scales comes from momentum flux injection to the interstellar medium from supernovae explosions. However, other channels of pressure in disk galaxies may also play a significant role in shaping the Ssfr at local scales. Our results also suggest that Phyd can be consider as the main driver of the star formation at kpc scales, rather than individual components of the baryonic mass.
2020 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), 2020
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Stroke: Vascular and Interventional Neurology, 2021
Introduction : Aneurysm wall enhancement using high‐resolution vessel wall imaging (HR‐VWI) may p... more Introduction : Aneurysm wall enhancement using high‐resolution vessel wall imaging (HR‐VWI) may provide new surrogate biomarkers for instability. Finite element analysis (FEA) paired with HR‐VWI can provide more insight into complex morphological features that ultimately lead to aneurysm growth and rupture. Methods : Unruptured intracranial aneurysms were reconstructed in 3D from CE‐MRA imaging. Shells were created assuming a uniform wall thickness of 86 μm and FEA was conducted with a 3rd order polynomial material model, assuming the wall to be isotropic, homogenous, and similar between subjects. The 95th percentile wall tension was defined as high wall tension to account for mesh artifacts. Low wall tension was identified from nodal values and verified on contour plots. Regions of high and low wall tension were characterized from contour plots. Aneurysms were measured and classified as enhancing (CR stalk ≥0.6) or non‐enhancing (CR stalk <0.6), using manual ROI measurements fro...
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET systems with a geometry different from a closed ring, the Time of Flight (TOF) of the anni... more In PET systems with a geometry different from a closed ring, the Time of Flight (TOF) of the annihilation photons appears to be relevant. Such a system capability helps to compensate the missing angular information that generates artifacts on the reconstructed images. In this work, two ASIC designs are evaluated for their use in PET systems having accurate coincidence resolving times (CRT) while preserving both energy and spatial resolutions. One of the ASIC options is the TOFPET1 from PETsys and the other the so-called PETIROC2 from Weeroc. Detection blocks based on scintillation LYSO crystal arrays have been used to first optimize the experiments. Parameters such as spatial, energy and time resolution have been obtained. Promising CRT results were found nearing 350 ps FWHM for a pair of photosensor channels (PETsys) and roughly 800 ps for all 16 against 16 channels (Weeroc). In terms of spatial resolution, 2 mm pixels size are well resolved with energy values approaching 15% have preliminary been measured for both ASICs. With the TOFPET1 ASIC, also tests with monolithic crystals were carried out. Those showed the system to provide depth of interaction (DOI) information. A DOI resolution (FWHM) of about 3 mm was preliminary estimated in a 25×25×10 mm3 LYSO scintillator. A calibration process for time alignment of the signal paths was carried out to provide accurate CRT results. The time walk error between channels was also compensated. Several methods for the timestamp averaging have been tried, resulting on preliminary CRT values in the 1 ns FWHM range.
Current Research Journal of Biological Sciences, 2019
Keeping in mind the relationship between the basal metabolic rate and the change in weight in the... more Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to generate a model of the same. As a result of data transformation, we obtained a graphic representation that is consistent with the original data. This representation manifested that after puberty, the parameter space loses its initial planarity. Thus, the model helps to sustain that the geometric phase changes that occur when the parameter space undergoes a gradual curvature, can contribute to explaining the biological aging process.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET detectors based in monolithic scintillators the interaction coordinates of each photon imp... more In PET detectors based in monolithic scintillators the interaction coordinates of each photon impact, in particular the 511 keV energy, can be determined from the light distribution sampled at the photosensors pixels. However, some of these distributions can be produced by pure dark noise from the SiPM photosensor, multi-interaction events with long travelled distance, pile-up, etc. Early rejection of these events can improve the SNR of the detector block and, as a result, in the also in reconstructed PET image. Moreover, this early rejection can reduce the statistics necessary to reconstruct those images preserving the SNR. To perform the rejection of noisy distributions, a comparison between a theoretical light distribution and the measured one is made by means of the Pearson product-moment correlation coefficient. This coefficient provides a metric, with range [−1, 1], suitable for assessing the similarity between the two distributions and, thus, allowing the rejection of uncorre...
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
A series of small size 22Na point sources have been simulated using GATE, following the NEMA prot... more A series of small size 22Na point sources have been simulated using GATE, following the NEMA protocol, and applied to the geometry of a brain dedicated PET so-called MindView. The simulated scanner geometry is currently composed by one ring of 20 detector blocks with a distance of about 330 mm between opposite detectors. Each detector module includes a monolithic LYSO crystal of 50 × 50 × 20 mm3 and a custom 12 × 12 SiPM array (TSV-type, SensL). The system defines an axial and trans-axial fields of view (FoV) of about 46 mm and 240 mm, respectively. The scintillation light inside the monolithic block was simulated in GEANT4 and is sampled following the readout scheme providing information on each SiPM array row and column (12 + 12). Out of this, three different approaches for the determination of the impact coordinates within the monolithic crystals have been considered. A first approach makes use of the center of gravity (CoG) calculation for the planar XY coordinates but the photo...
2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2017
The aim of this work is to show the potential capabilities of monolithic-based LYSO crystals, cou... more The aim of this work is to show the potential capabilities of monolithic-based LYSO crystals, coupled to large SiPM arrays to be considered as detector blocks for TOF-PET scanners. An ASIC read-out with accurate timing capabilities is used to independently process each SIPM element. Several studies have been carried out using both crystal arrays and monolithic blocks showing an overall good performance. The most relevant parameters evaluated in this work are: spatial, energy and time resolutions. We obtained coincidence resolving times as good as 340 ps FWHM for one to one coupling in crystal arrays and 1.2 ns FWHM using a monolithic block in coincidence with a 1 pixel reference detector.
Panamerican Journal of Trauma, Critical Care & Emergency Surgery, 2020
Introduction: Emergency pancreatoduodenectomy is a procedure that is indicated for the management... more Introduction: Emergency pancreatoduodenectomy is a procedure that is indicated for the management of severe pancreaticoduodenal trauma after damage control surgery. Objectives: To present our experience of pancreaticoduodenal trauma management with emergency pancreatoduodenectomy and damage control surgery. Materials and methods: Retrospectively recorded data of patients with severe pancreaticoduodenal trauma who underwent a pancreatoduodenectomy and damage control for trauma at a high-volume trauma center. Results: In a period of 6 years, four patients (three men and one woman, median age 17.5 years, range: 16-21 years) with severe pancreaticoduodenal trauma underwent a pancreatoduodenectomy and damage control procedure (gunshot n = 4), and in a second surgical procedure underwent gastrointestinal tract reconstruction. In total, 75% incidence of surgical site infection (SSI) was reported, 25% healthcare-associated pneumonia, and 50% postoperative pancreatic fistula (POPF). Intensive care unit (ICU) of 12.25 and hospital stay of 29.5 days mean and no mortality. Conclusion: An emergency pancreatoduodenectomy can be a lifesaving procedure in patients with non-reconstructable duodenopancreatic injuries. Damage control surgery in pancreaticoduodenal trauma is an alternative for management although with high risk of morbidity.
Liver Research, Disorders & Therapy, 2018
Introduction: A Bezoar is defined as a non-digestible foreign body trapped inside the digestive t... more Introduction: A Bezoar is defined as a non-digestible foreign body trapped inside the digestive tract usually ingested intentionally or accidentally. In 1779 Baudamant published the first case report of a bezoar in a human patient. Case report: We present a case of a patient in which a plastic bezoar, a toothbrush, was found as the etiologic factor of acute pancreatitis. We describe its management with laparoscopy and literature review. Discussion and conclusion: Although gastro-duodenal bezoars are rare, it is important to take them into account as a rare yet possible etiology of acute pancreatitis. A laparoscopic approach yields positive results in stable patients with no intestinal obstruction.
viii but not uniform in various parts of the world, leaving a gap in knowledge as to the proper r... more viii but not uniform in various parts of the world, leaving a gap in knowledge as to the proper response, and the mitigation of pitfalls needed. Objectives: Presenting and showing to the international community recent advances in hospital-and community-based interventions and violence prevention research from different regions of the world, performed in local contexts and framed in the new concepts of Global Violence Prevention.
Alzheimer's & Dementia, 2016
Revista Complutense de Educación, 2016
La organización y atención a la diversidad en centros de enseñanza secundaria de España........ 4... more La organización y atención a la diversidad en centros de enseñanza secundaria de España........ 4.1. La atención a la diversidad en el marco de la escuela inclusiva 4.2. La atención a la diversidad desde los Servicios psicopedagógicos 4.3. Proyectos, programas y planes para atender a la diversidad en los centros de educación secundaria 4.4. Procesos organizaqtivos implicados,condiciones y fases de los planes, programas y proyectos de atención a la diversidad 4.5. El camio hacia la inclusión en los centros de educación secundaria 4.6. Referencias bibliográficas Capítulo V La organización y atención a la diversidad en centros de enseñanza secundaria de México........ 5.1. Introducción 5.2. El Sistema educativo y la atención a la diversidad para menores entre 12 y 15 años de edad 5.3. Educación secundaria por televisión en México 5.4. ENLACE y el Programa para Mejorar el Logro Educativo 5.5. Conclusiones 5.6. Referencias bibliográficas Capítulo VI La organización y atención a la diversidad en centros de enseñanza secundaria de Nicaragua.... 6.1. Introducción 6.2. Políticas educativas relacionada con la atención a la diversidad en la Educación secundaria 6.3. Concepciones y prácticas sobre la atención a la diversidad en centros de educación secundaria 6.4. Comentarios y valoraciones de los resultados obtenidos 6.5. Referencias bibliográficas Capítulo VII La organización y atención a la diversidad en centros de educación media de Panamá............... 7.1. Introducción 7.2. La organización y atención a la diversidad en centros de educación media 7.3. La diversidad y los grupos vulnerabvles en las políticas educativas del país 7.4. La participación de los actores claves 7.5. Modelos y estrategias de atención a la diversidad y grupos vulnerables en los centros de educación media 7.6. La gestión en los centros de enseñanza que atienden la diversidad 7.7. Conclusiones 7.8. Referencias bibliográficas Capítulo VIII La organización y atención a la diversidad en centros de enseñanza secundaria de Paraguay..... 8.1. Legislación paraguaya 8.2. Atención a la diversidad 8.3. Educación inclusiva 8.4. Educación inclusiva y educación especial 8.5. Conclusiones 8.6. Referencias bibliográficas Capítulo IX La organización y atención a la diversidad en centros educativos de Perú.
Latin American Journal of Aquatic Research, 2016
RESUMEN. En la piscicultura el 30% de los nutrientes aportados son retenidos como biomasa animal ... more RESUMEN. En la piscicultura el 30% de los nutrientes aportados son retenidos como biomasa animal y el remanente se pierde en los sedimentos. Una alternativa es producir en policultivo, para aprovechar espacio y alimento. El objetivo del trabajo fue comparar y evaluar el crecimiento del sábalo Prochilodus lineatus en monocultivo, en contraste con policultivo de sábalo y pacú Piaractus mesopotamicus durante 11 meses. Se utilizaron cuatro tratamientos, control (sábalo 100/0), T1 (proporción sábalo-pacú 50/50), T2 (proporción sábalo-pacú 33/67), T3 (proporción sábalo-pacú 25/75); ubicados en estanques de tierra fertilizados. Se suministró diariamente alimento balanceado considerando el 5% de la biomasa. Se registraron parámetros de calidad de agua, además de realizarse biometrías mensuales. Los parámetros físicos y químicos de calidad de agua permanecieron dentro de valores adecuados para ambas especies en cada estanque. Las variables zootécnicas analizadas fueron: coeficiente de crecimiento específico, conversión alimenticia, productividad, supervivencia y peso vivo. La variable peso en T3 fue superior, diferenciándose significativamente del control (P < 0,05). Los valores de las otras variables fueron más altos que en los tratamientos restantes, pero sin diferencias significativas (P < 0,05). Si bien no se encontraron diferencias en cuatro de las cinco variables estudiadas, se observó una tendencia a favor de T3, la que pudo no ser estadísticamente significativa debido al escaso número de réplicas disponibles y a la alta variabilidad. Sin embargo, siguiendo la tendencia obtenida y bajo las condiciones experimentales, el sábalo presentó un mejor crecimiento y supervivencia cuando se encontró acompañado del pacú en una relación 25/75, constituyendo una alternativa satisfactoria para el cultivo de la especie. Palabras clave: cultivo semi-intensivo, factor de crecimiento específico, multiespecie, acuicultura.
Astronomische Nachrichten Supplement, Aug 1, 2004
Chemical Senses
A coated QCM static sensing system construction has been developed to analysis volatile organic c... more A coated QCM static sensing system construction has been developed to analysis volatile organic compounds frequently found in some positive and negative organoleptic olive oil attributes. The film-coated is composed by an adsorbent material onto a substrate which improves adherence and homogeneous distribution of adsorbent layer. Polyvinyl chloride (PVC) as substrate film and tetrahydrofuran (THF) as solvent have been used, analysing twelve PVC/ THF relations (0.25–50 mg/ml range) and seven dropped volumes (0.5–10 ml range). Sensor responses are measured as the stabilised oscillation frequency shift of the coated QCMsensor. PVC/THF = 1 relation and 10 ml dropped volume have been selected asQCMsubstrate film because they give the firmest sensor responses and constitute the greatest PVC film area. Operating parameters, such as measurement chamber temperature and sensor stabilisation time, have been optimised to improve the selectivity of the coated QCM sensor. After 15 minutes of sensor stabilisation time, volatile organic compounds, such as acetic acid, 1-octen-3-ol, 2-butanone, (Z)-3-hexenyl acetate, hexanal and undecane, are injected in a closed thermostat chamber, where coated QCM sensor is placed inside. OV–275 (1 mg) is used as adsorbent material. Changes in the oscillation frequency is registered each 5 seconds during 25 minutes. Measurement chamber temperature at 30 C. For acetic acid and (Z)-3-hexenyl acetate the highest frequency shifts are found at 30 C. 2-butanone, hexanal and 1-octen-3-ol exhibit great frequency shifts at 35 C, but there are low differences with oscillation frequency shifts at 30 C. The adsorption of undecane shows double frequency shift at 35 C than 30 C, but this nonpolar volatile does not interact with polar OV-275 polymer.