Initial Results and Literature Review

Aim: To evaluate the role of stereotactic body radiation therapy in the retreatment of locally recurrent cervical cancers. Brachytherapy is the main choice to treat gynecologic cancers. Methods: Patients with recurrent cervical cancer, previously submitted to radiotherapy, were treated with stereotactic body radiation therapy using a CyberKnife system (Accuray Incorporated, Sunnyvale, California) with a fiducial tracking system. Results: From August 2011 to October 2014, 5 patients have been treated. Median age was 81 years (range, 70-84 years). Two patients were diagnosed with adenocarcinoma endometrioid and 3 with squamous cell carcinoma. Toxicity was scored according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. After a median follow-up of 12 months (range, 8-34 months), no severe (>grade 3) acute/late genitourinary or low gastrointestinal toxicity was observed. Conclusion: Our preliminary results of stereotactic body radiation therapy "simulating" high dose rate for recurrent cervical cancers confirm a minimal toxicity and an optimal outcome. The stereotactic body radiation therapy is an alternative to high dose rate brachytherapy for gynecologic tumors

Sistemas de almacenamiento basados en baterías para su utilización en microredes eléctricas

Las microredes eléctricas utilizan sistemas de generación de energía eléctrica basados en fuentes de energía renovables y son capaces de operar en forma independiente del sistema interconectado de potencia. Dada la aleatoriedad del recurso de energía que generalmente utilizan, se hace indispensable el complemento de ese tipo de generación con almacenadores de energía. Hoy en día el uso de almacenadores de gran tamaño es no solo factible, sino también competitivo frente a otras opciones. En este trabajo se analizan los aspectos más importantes que debe tener un sistema de almacenamiento con baterías para ser utilizado en microredes eléctricas. Luego de ello se seleccionan las baterías que cumplen con la mayor cantidad de requisitos definidos y se muestran las características principales de cada tipo de batería. Se discute luego cuáles son las características más importantes para un modelo que las represente y se propone finalmente un modelo general válido para todos los tipos de baterías analizadas.Fil: Sarasua, Antonio Ernesto. Universidad Nacional de San Juan; ArgentinaFil: Molina, Marcelo Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; ArgentinaFil: Pontoriero, Domingo Hector. Universidad Nacional de San Juan; ArgentinaFil: Mercado, Pedro Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; Argentin

3D-Printing of Arteriovenous Malformations for Radiosurgical Treatment: Pushing Anatomy Understanding to Real Boundaries

open9noRadiosurgery of arteriovenous malformations (AVMs) is a challenging procedure. Accuracy of target volume contouring is one major issue to achieve AVM obliteration while avoiding disastrous complications due to suboptimal treatment. We describe a technique to improve the understanding of the complex AVM angioarchitecture by 3D prototyping of individual lesions. Arteriovenous malformations of ten patients were prototyped by 3D printing using 3D rotational angiography (3DRA) as a template. A target volume was obtained using the 3DRA; a second volume was obtained, without awareness of the first volume, using 3DRA and the 3D-printed model. The two volumes were superimposed and the conjoint and disjoint volumes were measured. We also calculated the time needed to perform contouring and assessed the confidence of the surgeons in the definition of the target volumes using a six-point scale. The time required for the contouring of the target lesion was shorter when the surgeons used the 3D-printed model of the AVM (p=0.001). The average volume contoured without the 3D model was 5.6 ± 3 mL whereas it was 5.2 ± 2.9 mL with the 3D-printed model (p=0.003). The 3D prototypes proved to be spatially reliable. Surgeons were absolutely confident or very confident in all cases that the volume contoured using the 3D-printed model was plausible and corresponded to the real boundaries of the lesion. The total cost for each case was 50 euros whereas the cost of the 3D printer was 1600 euros. 3D prototyping of AVMs is a simple, affordable, and spatially reliable procedure that can be beneficial for radiosurgery treatment planning. According to our preliminary data, individual prototyping of the brain circulation provides an intuitive comprehension of the 3D anatomy of the lesion that can be rapidly and reliably translated into the target volume.openCONTI, Alfredo; PONTORIERO, ANTONIO; IATI', GIUSEPPE; MARINO, DANIELE; LA TORRE, Domenico; VINCI, Sergio Lucio; GERMANO', Antonino Francesco; PERGOLIZZI, Stefano; TOMASELLO, FrancescoCONTI, Alfredo; PONTORIERO, ANTONIO; IATI', GIUSEPPE; MARINO, DANIELE; LA TORRE, Domenico; VINCI, Sergio Lucio; GERMANO', Antonino Francesco; PERGOLIZZI, Stefano; TOMASELLO, Francesc

Integración de energía eólica y sistemas de almacenamiento en sistemas de suministro de energía eléctrica

Los avances tecnológicos en el área de electrónica de potencia y los incentivos para la instalación de grandes sistemas de generación de energía eléctrica basados en fuentes de energía renovables, posibilitan hoy en día que experiencias aisladas o pequeñas de energías renovables puedan ser aplicadas en sistemas eléctricos de potencia a gran escala. Entre los sistemas basados en energías renovables, se destacan los eólicos por ser los de mayor envergadura y capacidad. Dada la aleatoriedad del recurso que utilizan, para grandes niveles de penetración, la estabilidad del sistema de potencia debe ser revisada para garantizar la seguridad y con ello la continuidad del servicio eléctrico. En este trabajo se analizan los aspectos de seguridad que involucra la inclusión de grandes granjas eólicas en los sistemas de potencia y se propone un esquema de incorporación de energía eólica y almacenamiento de energía para su inclusión en forma segura en estos sistemas.Power systems around the world require performing various tasks at the same time. The necessity to generate electricity at low cost, with less or null pollution and the cost increase of petroleum, put power utilities on a large and permanent stress. Renewable energy sources like wind generation is today part of a solution for various utilities problems. They are in first place concerning low pollution and the combustible has null cost. They have unfortunately a big problem: they are unpredictable. Especially in the case of wind for short periods it is difficult to assure its generation. Power systems operator cannot take into account wind farms in operational planning stage. This paper discusses the conditions for wind energy can take part of the spinning reserve in power system and make a proposal to include wind farms in spinning reserve with help of energy storage systems.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Integración de energía eólica y sistemas de almacenamiento en sistemas de suministro de energía eléctrica

Los avances tecnológicos en el área de electrónica de potencia y los incentivos para la instalación de grandes sistemas de generación de energía eléctrica basados en fuentes de energía renovables, posibilitan hoy en día que experiencias aisladas o pequeñas de energías renovables puedan ser aplicadas en sistemas eléctricos de potencia a gran escala. Entre los sistemas basados en energías renovables, se destacan los eólicos por ser los de mayor envergadura y capacidad. Dada la aleatoriedad del recurso que utilizan, para grandes niveles de penetración, la estabilidad del sistema de potencia debe ser revisada para garantizar la seguridad y con ello la continuidad del servicio eléctrico. En este trabajo se analizan los aspectos de seguridad que involucra la inclusión de grandes granjas eólicas en los sistemas de potencia y se propone un esquema de incorporación de energía eólica y almacenamiento de energía para su inclusión en forma segura en estos sistemas.Power systems around the world require performing various tasks at the same time. The necessity to generate electricity at low cost, with less or null pollution and the cost increase of petroleum, put power utilities on a large and permanent stress. Renewable energy sources like wind generation is today part of a solution for various utilities problems. They are in first place concerning low pollution and the combustible has null cost. They have unfortunately a big problem: they are unpredictable. Especially in the case of wind for short periods it is difficult to assure its generation. Power systems operator cannot take into account wind farms in operational planning stage. This paper discusses the conditions for wind energy can take part of the spinning reserve in power system and make a proposal to include wind farms in spinning reserve with help of energy storage systems.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Integración de energía eólica y sistemas de almacenamiento en sistemas de suministro de energía eléctrica

Los avances tecnológicos en el área de electrónica de potencia y los incentivos para la instalación de grandes sistemas de generación de energía eléctrica basados en fuentes de energía renovables, posibilitan hoy en día que experiencias aisladas o pequeñas de energías renovables puedan ser aplicadas en sistemas eléctricos de potencia a gran escala. Entre los sistemas basados en energías renovables, se destacan los eólicos por ser los de mayor envergadura y capacidad. Dada la aleatoriedad del recurso que utilizan, para grandes niveles de penetración, la estabilidad del sistema de potencia debe ser revisada para garantizar la seguridad y con ello la continuidad del servicio eléctrico. En este trabajo se analizan los aspectos de seguridad que involucra la inclusión de grandes granjas eólicas en los sistemas de potencia y se propone un esquema de incorporación de energía eólica y almacenamiento de energía para su inclusión en forma segura en estos sistemas.Power systems around the world require performing various tasks at the same time. The necessity to generate electricity at low cost, with less or null pollution and the cost increase of petroleum, put power utilities on a large and permanent stress. Renewable energy sources like wind generation is today part of a solution for various utilities problems. They are in first place concerning low pollution and the combustible has null cost. They have unfortunately a big problem: they are unpredictable. Especially in the case of wind for short periods it is difficult to assure its generation. Power systems operator cannot take into account wind farms in operational planning stage. This paper discusses the conditions for wind energy can take part of the spinning reserve in power system and make a proposal to include wind farms in spinning reserve with help of energy storage systems.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Post-Treatment Edema after Meningioma Radiosurgery is a Predictable Complication

Symptomatic post-treatment edema (PTE) causing seizures, focal deficits, and intracranial hypertension is a rather common complication of meningioma radiosurgery. Factors associated to the occurrence of PTE still needs to be clarified. We retrospectively analyzed our patients' data to identify factors associated with the development of symptomatic PTE. Supposed risk factors were systematically analyzed. Between July 2007 and March 2014, 245 meningiomas in 229 patients were treated by a single fraction or multisession radiosurgery (2-5 fractions) or hypofractionated stereotactic radiotherapy (6-15 fractions) using the CyberKnife system (Accuray Inc., Sunnyvale, CA) at the University Hospital of Messina, Italy. Local tumor control was achieved in 200 of 212 patients with World Health Organization (WHO) Grade I meningiomas (94%) at a mean follow-up of 62 months. Symptomatic PTE on MRI was diagnosed in 19 patients (8.3%) causing seizure (n=17, 89%), aggravating headache (n=12, 63%), or focal deficits (n=13, 68%). Four variables were found to be associated with the likelihood of edema development, including tumor volume > 4.5 mL, non-basal tumor location, tight brain/tumor interface, and atypical histology. Nonetheless, when multivariate logistic regression analysis was performed, only tumor volume and brain-tumor interface turned out to be independent predictors of PTE development. Our results suggest that the factor associated with the risk of developing PTE is associated to characteristics of meningioma rather than to the treatment modality used. Accordingly, an appropriate patient selection is the way to achieve safe treatment and long-term disease control

Image-guided robotic radiosurgery for the treatment of arteriovenous malformations

Cerebral arteriovenous malformations (AVMs) are challenging lesions, often requiring multimodal interventions; however, data on the efficacy of stereotactic radiosurgery for cerebral AVMs are limited. This study aimed to evaluate the clinical and radiographic results following robotic radiosurgery, alone or in combination with endovascular treatment, and to investigate factors associated with obliteration and complications in patients with AVM

Pattern of care for re-irradiation in locally recurrent rectal cancer: a national survey on behalf of the AIRO gastrointestinal tumors study group

PurposeRadical resection (R0) represents the best curative treatment for local recurrence (LR) rectal cancer. Re-irradiation (re-RT) can increase the rate of R0 resection. Currently, there is a lack of guidelines on Re-RT for LR rectal cancer. The Italian Association of Radiation and clinical oncology for gastrointestinal tumors (AIRO-GI) study group released a national survey to investigate the current clinical practice of external beam radiation therapy in these patients.Material and methodsIn February 2021, the survey was designed and distributed to members of the GI working group. The questionnaire consisted of 40 questions regarding center characteristics, clinical indications, doses, and treatment techniques of re-RT for LR rectal cancer.ResultsA total of 37 questionnaires were collected. Re-RT was reported as an option for neoadjuvant treatment in resectable and unresectable disease by 55% and 75% of respondents, respectively. Long-course treatment with 30-40 Gy (1.8-2 Gy/die, 1.2 Gy bid) and hypofractionated regimen of 30-35 Gy in 5 fractions were used in most centers. A total dose of 90-100 Gy as EqD2 dose (& alpha;/& beta; = 5 Gy) was delivered by 46% of the respondents considering the previous treatment. Modern conformal techniques and daily image-guided radiation therapy protocols were used in 94% of centers.ConclusionOur survey showed that re-RT treatment is performed with advanced technology that allow a good management of LR rectal cancer. Significant variations were observed in terms of dose and fractionation, highlighting the need for a consensus on a common treatment strategy that could be validated in prospective studies

Interpretation of major structures of payenia applying the gravimetric potential method

Por medio de la aplicación de los métodos potenciales se pudieron caracterizar los depocentros andinos del borde noroeste de la Cuenca Neuquina, situados en la provincia geológica de Payenia, facilitando el estudio de estructuras emplazadas a nivel cortical. Para ello se efectuaron mediciones gravimétricas apoyadas con diferencial GPS en modo posproceso para obtener las coordenadas de las estaciones (DGPS-700 estaciones), se recopilaron y controlaron más de 10000 valores de gravedad provenientes de distintas campañas relevados durante las últimas tres décadas, que forman parte de la base de datos del Instituto Geofísico Sismológico Volponi (IGSV). Se construyeron mapas gravimétricos que luego fueron filtrados con el objetivo de estudiar las fuentes ubicadas en la corteza superior. Consecuentemente se prepararó un modelo en 3D obtenido por inversión gravimétrica, integrando información geológica y geofísica disponible. El modelo 3D del espesor sedimentario tiene en cuenta variaciones laterales y verticales de la densidad obtenidas de afloramientos y de pozos de exploración de hidrocarburos. Esto permitió identificar altos y bajos estructurales estudiados en 2D por otros autores e identificar una subcuenca, no reportada hasta el presente, en el borde este de la faja plegada y corrida de Malargüe y que se acuña con los afloramientos del basamento cristalino del Bloque de San Rafael.The Andean depocenters in the northwestern border of the Neuquén basin, in the geologic province of Payenia, were characterized by means of the analyzed methods to support hydrocarbon exploration in the area. These techniques allowed studying the upper crust structures to perform oil exploration. Gravity measurements were effected and supported with GDPS (700 stations). More than 10,000 gravity values, which were provided from several campaigns over the last three decades and which constitute the database of the Geophysics and Seismological Institute “Volponi”, were also used and checked. Bouguer gravity anomalies were mapped and filtered to study the upper crust sources. We made a 3D model (by gravity inversion) integrating geological and geophysical data that emphasized the resolution of the structures placed in this area. The 3D model of the sedimentary thickness takes into account lateral and vertical density variations obtained from local wells. This model allowed identification in 2D of high and low structures studied by other authors as wellas a sub-basin, not reported up to now, found on the eastern edge of the fold and thrust belt of Malargüe that is wedged into a raised basement block belonging to the San Rafael blockFil: Anci Araniti, Sheila Anabel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Ruiz, Francisco. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; ArgentinaFil: Lince Klinger, Federico Gustavo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Leiva, Maria Flavia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Sanchez, Marcos Ariel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Alvarez Pontoriero, Orlando. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Garcia, Hector Pedro Antonio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Acosta, Gemma. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentin