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

Análisis de la cuenca del Bermejo en los últimos 8 Ma.

En el presente trabajo se propone un modelo isostático flexural elástico como mecanismo dominante en la generación de las estructuras de la cuenca de antepaís del Bermejo. La región de estudio a partir del Neógeno se comportó de forma diferente, pudiendo dividirse por lo menos en dos etapas. La primera, desde la formación de la cuenca de antepaís andino, hasta el inicio del levantamiento de las sierras Pampeanas occidentales, donde el mecanismo predominante fue la flexión elástica. La segunda etapa, motivo del presente trabajo, que abarca desde la reactivación de la megafalla Desaguadero- Bermejo hasta el presente, donde comienza a actuar el mecanismo de flexión elástica en corteza discontinua o rota. Las respuestas flexurales obtenidas para una corteza con un espesor elástico equivalente (Te) entre 5 y 7 km generan una geometría consistente con la actual cuenca del Bermejo y con los modelos de corteza previamente justificados a partir de la anomalía residual de Bouguer.In the present work, we propose an elastic isostatic flexural model as the dominant mechanism in the generation of structures of the Bermejo foreland basin.The study area has behaved in a different way from the Neogene, therefore it has been divided into at least two stages. The first one, initiates with the formation of the Andean foreland basin up to the beginning of the lifting of Western Sierras Pampeanas. In this stage, the elastic flexure was the predominant mechanism. The second stage, which motivates our work, comprises from the reactivation of the mega fault of Bermejo-Desaguadero up to now, when initiates the elastic bending mechanism on the discontinuous or broken crust.The flexural responses obtained for a crust with an equivalent elastic thickness (Te) between 5 and 7 km, generates a geometry consistent with the current Bermejo basin. These responses are also consistent with the crustal models previously justified from the Bouguer residual anomaly.Asociación Argentina de Geofísicos y Geodesta

Exploring deep cervical compartments in head and neck surgical oncology through augmented reality vision: a proof of concept

Virtual surgical planning allows surgeons to meticulously define surgical procedures by creating a digital replica of patients' anatomy. This enables precise preoperative assessment, facilitating the selection of optimal surgical approaches and the customization of treatment plans. In neck surgery, virtual planning has been significantly underreported compared to craniofacial surgery, due to a multitude of factors, including the predominance of soft tissues, the unavailability of intraoperative navigation and the complexity of segmenting such areas. Augmented reality represents the most innovative approach to translate virtual planning for real patients, as it merges the digital world with the surgical field in real time. Surgeons can access patient-specific data directly within their field of view, through dedicated visors. In head and neck surgical oncology, augmented reality systems overlay critical anatomical information onto the surgeon's visual field. This aids in locating and preserving vital structures, such as nerves and blood vessels, during complex procedures. In this paper, the authors examine a series of patients undergoing complex neck surgical oncology procedures with prior virtual surgical planning analysis. For each patient, the surgical plan was imported in Hololens headset to allow for intraoperative augmented reality visualization. The authors discuss the results of this preliminary investigation, tracing the conceptual framework for an increasing AR implementation in complex head and neck surgical oncology procedures

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