Deconfined fractional electric charges in graphene at high magnetic fields

The resistance at the charge neutral (Dirac) point was shown by Checkelsky et al in Phys. Rev. B 79, 115434 (2009) to diverge upon the application of a strong magnetic field normal to graphene. We argue that this divergence is the signature for a Kekule instability of graphene, which is induced by the magnetic field. We show that the strong magnetic field does not remove the zero modes that bind a fraction of the electron around vortices in the Kekule dimerization pattern, and that quenched disorder present in the system makes it energetically possible to separate the fractional charges. These findings, altogether, indicate that graphene can sustain deconfined fractionalized electrons.Comment: 11 pages, 2 figure

A New Approach for Split Renal Function Assessment Based on 3D-Models Generated from Contrast-enhanced Multi-slice Computed Tomography (Msct) Scans and Mathematical Analysis: A Pilot Study

Introduction: Instrumental methods of examination may alter the course of treatment and patients’ management: from minimally invasive nephron-sparing procedures to radical operations. Objective:to present preliminary data on split kidney function assessment (in a kidney volume, e.g. segment) in patients with urological diseases.Materials and methods: A prospective study was launched in aResearch Institute for Uronephrology and Reproductive Health from November, 2015 to February, 2017. 31 patients were enrolled into the study: 15 with stone kidney disease, 2 with kidney anomalies, 14 with renal tumors. Contrast-enhanced CT with 3D-models andmathematical analysis were performed in all patients. Correlation between CT-based and renal scintigraphy-based measures of split renal function was estimated. Results: CT-based methods for the calculation of split renal function with 3D-models showed correlation with renal scintigraphy (p<0.004, ttest). Conclusion: A new approach for split kidney function assessment based on contrast-enhanced CT with 3D-models and mathematical analysis allows for both acquiring detailed data on clinical anatomy and evaluation of renal function to promote preoperative decision-making

ИСПОЛЬЗОВАНИЕ ИНТРАОПЕРАЦИОННОЙ НАВИГАЦИИ ПРИ ОРГАНОСОХРАНЯЮЩИХ ХИРУРГИЧЕСКИХ ВМЕШАТЕЛЬСТВАХ ПО ПОВОДУ ОПУХОЛИ ПОЧКИ

The quest for organ-saving surgery sends us in search of new preoperative examination methods to successfully perform partial nephrectomy. The Research Institute of Uronephrology and Reproductive Health, I.M. Sechenov First Moscow State Medical University, has introduced a radically new procedure, which was previously unused in urologic care, namely computer simulation of a pathological process that allows not only a preoperative three-dimensional image of a kidney tumor and an exhaustive account of its relationship to the calyceal-pelvic system, renal vessels, angioarchitectonics of the kidney concerned, and extrarenal landmarks, but also virtual tumor removal, by informing an operator about the anatomical masses being located in the resected tumor bed. Of prime importance is that a polymer plastic template that will intraoperatively fulfill the function of a navigator to outline the external tumor margins onto the renal surface can be designed.Стремление выполнять органосохраняющие операции заставляет искать все новые и новые методы предоперационного обследования с целью удачного выполнения резекции почки. На базе НИИ уронефрологии и репродуктивного здоровья человека при Первом МГМУ им. И.М. Сеченова внедрена совершенно новая, не применяемая ранее в урологии методика — компьютерное моделирование патологического процесса, которая дает возможность на дооперационном этапе получить трехмерное изображение не только новообразования почки, исчерпывающую информацию о ее «взаимоотношении» с чашечно-лоханочной системой, сосудами почки, ангиоархитектоникой исследуемой почки, внепочечными ориентирами, но и позволяет выполнить виртуальное удаление опухоли, информируя оператора об анатомических образованиях, локализованных в ложе резецированной ткани. Особо необходимо отметить возможность создания полимерного пластикового шаблона, который интраоперационно будет выполнять роль навигатора для маркировки внешних границ опухоли на поверхности почки

Computer-assisted simulation as an innovation technique in diagnosis and planning of treatment of patients with surgical kidney diseases

Aim: to improve visualization and outcomes of surgical management in patients presenting with diseases of the kidneys and upper urinary tracts. Patients and methods: all patients with renal tumours, coral-like nephrolithiasis, and hydronephrosis were preoperatively subjected to a routine protocol of contrast-enhanced multispiral computed tomography (MSCT) of the kidneys, with the study performed according to the programme 1.25/1.25 mm with intravenous administration of 100 pL of a contrast medium at a rate of 3 ml/sec. at a tube voltage of 80 kV, and current strength of 350 mA). The findings of MSCT were then computer- processed using a special program for 3D images, thus making it possible to obtain 3D objects of the pathologically damaged organ. The obtained 3D and 4D images were subjected to thorough analysis in each individual case, thus making it possible to initially reconstruct the common pathological pattern, followed by duly planning the course of the future operative procedures to perform. Results: in all cases presented, computer-assisted simulation gave a comprehensive pattern of the pathological process in the kidneys and upper urinary tracts. The obtained findings allowed us not only to predict possible intraoperative complications (haemorrhage, formation of a urinary fistula, creation of “extra” ports during percutaneous operations, etc.) but also to work out measures aimed at their prevention, as well as to determine the scope and the stages of the would-be care and cure. Conclusion: according to our own experience, computer-assisted simulation is currently becoming an important and intrinsic stage during preoperative preparation of patients presenting with kidney diseases.Цель: улучшить визуализацию и результаты оперативного лечения у пациентов с заболеваниями почек и верхних мочевых путей. Процедура исследования: всем пациентам с опухолью почек, коралловидным нефролитиазом и гидронефрозом на дооперационном этапе выполнена МСКТ почек с контрастированием по стандартному протоколу (исследование выполнялось по программе 1.25/1.25 мм. с внутривенным введением 100 мл. контрастного вещества со скоростью 3 мл/сек., напряжение 80 кВ, сила тока 350 мА). В последующем результаты МСКТ подвергались компьютерной обработке в специальной программе для 3D изображений, что позволяло получать трехмерные объекты пораженного патологическим процессом органа. Полученные в 3D и 4D формате изображения подвергались тщательному анализу в каждом индивидуальном наблюдении, что позволяло вначале воссоздать единую патологическую картину, а в последующем спланировать ход предстоящих оперативных действий. Результаты: во всех представленных наблюдениях компьютерное моделирование дало исчерпывающую картину о патологическом процессе в почках и верхних мочевых путях. Данная информация позволила не только спрогнозировать возможные осложнения во время операции (кровотечение, формирование мочевого свища, создание «лишних» портов при перкутанных операциях и т.д.), но также разработать меры по их профилактике, определить объем и этапы предстоящего пособия. Выводы: у пациентов с заболеваниями почек компьютерное моделирование, по нашему собственному опыту, становится важным и неотъемлемым этапом в их предоперационной подготовке на сегодняшний день

USE OF INTRAOPERATIVE NAVIGATION DURING ORGAN-SAVING SURGERY FOR KIDNEY TUMOR

The quest for organ-saving surgery sends us in search of new preoperative examination methods to successfully perform partial nephrectomy. The Research Institute of Uronephrology and Reproductive Health, I.M. Sechenov First Moscow State Medical University, has introduced a radically new procedure, which was previously unused in urologic care, namely computer simulation of a pathological process that allows not only a preoperative three-dimensional image of a kidney tumor and an exhaustive account of its relationship to the calyceal-pelvic system, renal vessels, angioarchitectonics of the kidney concerned, and extrarenal landmarks, but also virtual tumor removal, by informing an operator about the anatomical masses being located in the resected tumor bed. Of prime importance is that a polymer plastic template that will intraoperatively fulfill the function of a navigator to outline the external tumor margins onto the renal surface can be designed

USE OF INTRAOPERATIVE NAVIGATION DURING ORGAN-SAVING SURGERY FOR KIDNEY TUMOR

The quest for organ-saving surgery sends us in search of new preoperative examination methods to successfully perform partial nephrectomy. The Research Institute of Uronephrology and Reproductive Health, I.M. Sechenov First Moscow State Medical University, has introduced a radically new procedure, which was previously unused in urologic care, namely computer simulation of a pathological process that allows not only a preoperative three-dimensional image of a kidney tumor and an exhaustive account of its relationship to the calyceal-pelvic system, renal vessels, angioarchitectonics of the kidney concerned, and extrarenal landmarks, but also virtual tumor removal, by informing an operator about the anatomical masses being located in the resected tumor bed. Of prime importance is that a polymer plastic template that will intraoperatively fulfill the function of a navigator to outline the external tumor margins onto the renal surface can be designed