Search results for "processi"
showing 10 items of 9638 documents
Adaptive scheduling of acceleration and gyroscope for motion artifact cancelation in photoplethysmography
2022
Background and objective: Recently, various algorithms have been introduced using wrist-worn photo-plethysmography (PPG) to provide high accuracy of instantaneous heart rate (HR) estimation, including during high-intensity exercise. Most studies focus on using acceleration and/or gyroscope signals for the motion artifact (MA) reference, which attenuates or cancels out noise from the MA-corrupted PPG signals. We aim to open and pave the path to find an appropriate MA reference selection for MA cancelation in PPG.Methods: We investigated how the acceleration and gyroscope reference signals correlate with the MAs of the distorted PPG signals and derived both mathematically and experimentally a…
Type-2 Fuzzy Control of a Bioreactor
2009
Abstract—In this paper the control of a bioprocess using an adaptive type-2 fuzzy logic controller is proposed. The process is concerned with the aerobic alcoholic fermentation for the growth of Saccharomyces Cerevisiae a n d i s characterized by nonlinearity and parameter uncertainty. Three type-2 fuzzy controllers heve been developed and tested by simulation: a simple type-2 fuzzy logic controller with 49 rules; a type-2 fuzzyneuro- predictive controller (T2FNPC); a t y p e -2 selftuning fuzzy controller ( T2STFC). The T2FNPC combines the capability of the type-2 fuzzy logic to handle uncertainties, with the ability of predictive control to predict future plant performance making use of a…
A distributed real-time data prediction and adaptive sensing approach for wireless sensor networks
2018
International audience; Many approaches have been proposed in the literature to reduce energy consumption in Wireless Sensor Networks (WSNs). Influenced by the fact that radio communication and sensing are considered to be the most energy consuming activities in such networks. Most of these approaches focused on either reducing the number of collected data using adaptive sampling techniques or on reducing the number of data transmitted over the network using prediction models. In this article, we propose a novel prediction-based data reduction method. furthermore, we combine it with an adaptive sampling rate technique, allowing us to significantly decrease energy consumption and extend the …
Virtual reality system for planning minimally invasive neurosurgery
2008
Object The authors report on their experience with a 3D virtual reality system for planning minimally invasive neurosurgical procedures. Methods Between October 2002 and April 2006, the authors used the Dextroscope (Volume Interactions, Ltd.) to plan neurosurgical procedures in 106 patients, including 100 with intracranial and 6 with spinal lesions. The planning was performed 1 to 3 days preoperatively, and in 12 cases, 3D prints of the planning procedure were taken into the operating room. A questionnaire was completed by the neurosurgeon after the planning procedure. Results After a short period of acclimatization, the system proved easy to operate and is currently used routinely for pre…
Autostereoscopic Three-Dimensional Neuronavigation to the Sella: Technical Note.
2017
Background A drawback of conventional neuronavigation is the necessity of focusing on two-dimensional images in 3 planes at the same time to determine one's position in the operating field. A solution would be to merge the images into a single three-dimensional (3D) image that mirrors the actual anatomy. The introduction of holographic glassless 3D monitors paved the way to 3D navigation. We present our experience with 3D neuronavigation as exemplified by navigation to and within the sella. Methods Operative planning was conducted with a navigation system using cranial computed tomography and magnetic resonance imaging. The image data sets were processed by the prototype Clariti 3D system t…
Perfusion MRI in normal and abnormal pituitary gland. A preliminary study.
1997
Perfusion MRI (magnetic resonance imaging) of the pituitary gland was performed in 20 healthy volunteers and 63 patients with various lesions involving the pituitary gland. All patients underwent sequential contrast-enhanced MRI using spoiled gradient recalled sequences with high temporal resolution (7 seconds). Four pituitary areas (pituitary stalk, posterior lobe, postero-superior, and antero-inferior adenohypophysis) were tested with a selected region of interest. Maximal contrast percentual variation was calculated. The timing of enhancement in normal patients matched perfectly with normal pituitary vascularization. Abnormal timing in pathological condition was investigated.
3D microvascular architecture of pre-cancerous lesions and invasive carcinomas of the colon.
2001
Despite the significance of tumour neoangiogenesis and the extensive knowledge on the molecular basis of blood vessel formation currently no quantitative data exist on the 3D microvascular architecture in human primary tumours and their precursor lesions. This prompted us to examine the 3D vascular network of normal colon mucosa, adenomas and invasive carcinomas by means of quantitative microvascular corrosion casting. Fresh hemicolectomy specimens from 20 patients undergoing cancer or polyposis coli surgery were used for corrosion casting, factor VIII and VEGF immunostaining. In addition, immunostaining was done on colorectal tissue from 33 patients with metastatic and non-metastatic carci…
Novel mutations of the MET proto-oncogene in papillary renal carcinomas.
1999
Hereditary papillary renal carcinoma (HPRC) is characterized by multiple, bilateral papillary renal carcinomas. Previously, we demonstrated missense mutations in the tyrosine kinase domain of the MET proto-oncogene in HPRC and a subset of sporadic papillary renal carcinomas. In this study, we screened a large panel of sporadic papillary renal carcinomas and various solid tumors for mutations in the MET proto-oncogene. Summarizing these and previous results, mutations of the MET proto-oncogene were detected in 17/129 sporadic papillary renal carcinomas but not in other solid tumors. We detected five novel missense mutations; three of five mutations were located in the ATP-binding region of t…
High-definition imaging in endoscopic transsphenoidal pituitary surgery.
2011
Background The transsphenoidal approach to sellar lesions has evolved enormously since its first description in the early 20th century. Endoscopic surgical strategies have become an integral part of the surgical armamentarium. More recently, high-definition (HD) digital cameras with better image resolution were introduced, although their value for the surgical procedure remains equivocal. The purpose of this study was to compare the image quality of a standard-definition (SD) camera with a new HD camera. Methods A transsphenoidal pituitary adenomectomy was recorded simultaneously in HD and SD resolution. Eight experienced neurosurgeons were asked to identify predefined as well as not predef…
Regulation of ISWI chromatin remodelling activity.
2013
The packaging of the eukaryotic genome into chromatin facilitates the storage of the genetic information within the nucleus, but prevents the access to the underlying DNA sequences. Structural changes in chromatin are mediated by several mechanisms. Among them, ATP-dependent remodelling complexes belonging to ISWI family provides one of the best examples that eukaryotic cells evolved to finely regulate these changes. ISWI-containing complexes use the energy derived from ATP hydrolysis to rearrange nucleosomes on chromatin in order to favour specific nuclear reactions. The combination of regulatory nuclear factors associated with the ATPase subunit as well as its modulation by specific histo…