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671.
Tutar IB Pathak SD Gong L Cho PS Wallner K Kim Y 《IEEE transactions on medical imaging》2006,25(12):1645-1654
Prostate brachytherapy quality assessment procedure should be performed while the patient is still on the operating table since this would enable physicians to implant additional seeds immediately into the prostate if necessary thus reducing the costs and increasing patient outcome. Seed placement procedure is readily performed under fluoroscopy and ultrasound guidance. Therefore, it has been proposed that seed locations be reconstructed from fluoroscopic images and prostate boundaries be identified in ultrasound images to perform dosimetry in the operating room. However, there is a key hurdle that needs to be overcome to perform the ultrasound and fluoroscopy-based dosimetry: it is highly time-consuming for physicians to outline prostate boundaries in ultrasound images manually, and there is no method that enables physicians to identify three-dimensional (3-D) prostate boundaries in postimplant ultrasound images in a fast and robust fashion. In this paper, we propose a new method where the segmentation is defined in an optimization framework as fitting the best surface to the underlying images under shape constraints. To derive these constraints, we modeled the shape of the prostate using spherical harmonics of degree eight and performed statistical analysis on the shape parameters. After user initialization, our algorithm identifies the prostate boundaries on the average in 2 min. For algorithm validation, we collected 30 postimplant prostate volume sets, each consisting of axial transrectal ultrasound images acquired at 1-mm increments. For each volume set, three experts outlined the prostate boundaries first manually and then using our algorithm. By treating the average of manual boundaries as the ground truth, we computed the segmentation error. The overall mean absolute distance error was 1.26 +/- 0.41 mm while the percent volume overlap was 83.5 +/- 4.2. We found the segmentation error to be slightly less than the clinically-observed interobserver variability. 相似文献
672.
Atrazine is one of the most heavily used herbicide worldwide. Atrazine has been detected in ground and surface waters in many countries beyond permissible limits due to its low vapor pressure, long persistence, and low biodegradability. This study aims to develop a bacterial biomass which can be used as biosorbent to remove the atrazine from waters easily and cost-effectively. Here, fourteen bacterial strains were isolated from soil having the history of atrazine contamination and batch experiments were carried with biosorbents prepared from various bacterial isolates. The biosorbent BS-1 developed from strain C1 was found be the best for the removal of atrazine. 相似文献
673.
Nicholas A. Kotov Jessica O. Winter Isaac P. Clements Edward Jan Brian P. Timko Stéphane Campidelli Smita Pathak Andrea Mazzatenta Charles M. Lieber Maurizio Prato Ravi V. Bellamkonda Gabriel A. Silva Nadine Wong Shi Kam Fernando Patolsky Laura Ballerini 《Advanced materials (Deerfield Beach, Fla.)》2009,21(40):3970-4004
This review focuses on the application of nanomaterials for neural interfacing. The junction between nanotechnology and neural tissues can be particularly worthy of scientific attention for several reasons: (i) Neural cells are electroactive, and the electronic properties of nanostructures can be tailored to match the charge transport requirements of electrical cellular interfacing. (ii) The unique mechanical and chemical properties of nanomaterials are critical for integration with neural tissue as long‐term implants. (iii) Solutions to many critical problems in neural biology/medicine are limited by the availability of specialized materials. (iv) Neuronal stimulation is needed for a variety of common and severe health problems. This confluence of need, accumulated expertise, and potential impact on the well‐being of people suggests the potential of nanomaterials to revolutionize the field of neural interfacing. In this review, we begin with foundational topics, such as the current status of neural electrode (NE) technology, the key challenges facing the practical utilization of NEs, and the potential advantages of nanostructures as components of chronic implants. After that the detailed account of toxicology and biocompatibility of nanomaterials in respect to neural tissues is given. Next, we cover a variety of specific applications of nanoengineered devices, including drug delivery, imaging, topographic patterning, electrode design, nanoscale transistors for high‐resolution neural interfacing, and photoactivated interfaces. We also critically evaluate the specific properties of particular nanomaterials—including nanoparticles, nanowires, and carbon nanotubes—that can be taken advantage of in neuroprosthetic devices. The most promising future areas of research and practical device engineering are discussed as a conclusion to the review. 相似文献
674.
Pathak Aditya Sethuraman Ganesh Ongel Aybike Lienkamp Markus 《Forschung im Ingenieurwesen》2021,85(2):431-442
Forschung im Ingenieurwesen - Electrification and automation are attracting interest from the public-transportation sector for their potential to improve energy efficiency, cost efficiency, and... 相似文献
675.
Microsystem Technologies - The present work reports a numerical investigation of droplet formation and breakup in a specially designed ribbed microfluidic T-junction. The ribbed microfluidic... 相似文献
676.
Rahul Singh Saurabh Pathak Komal Jain Noorjahan Sang-Koog Kim 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(39):2205741
The effective thermal management of electronic system holds the key to maximize their performance. The recent miniaturization trends require a cooling system with high heat flux capacity, localized cooling, and active control. Nanomagnetic fluids (NMFs) based cooling systems have the ability to meet the current demand of the cooling system for the miniaturized electronic system. However, the thermal characteristics of NMFs have a long way to go before the internal mechanisms are well understood. This review mainly focuses on the three aspects to establish a correlation between the thermal and rheological properties of the NMFs. First, the background, stability, and factors affecting the properties of the NMFs are discussed. Second, the ferrohydrodynamic equations are introduced for the NMFs to explain the rheological behavior and relaxation mechanism. Finally, different theoretical and experimental models are summarized that explain the thermal characteristics of the NMFs. Thermal characteristics of the NMFs are significantly affected by the morphology and composition of the magnetic nanoparticles (MNPs) in NMFs as well as the type of carrier liquids and surface functionalization that also influences the rheological properties. Thus, understanding the correlation between the thermal characteristics of the NMFs and rheological properties helps develop cooling systems with improved performance. 相似文献
677.
Gupta Abhinav Rai Sanjeev Kumar Nitish Sigroha Deepak Kishore Arunabh Pathak Varnika Rahman Ziya Ur 《SILICON》2022,14(3):1005-1012
Silicon - It is a well-known fact that the gate stacking is used to improve the electrostatic behavior of Si0.5Ge0.5 Junctionless Gate-All-Around (JL-GAA) MOSFETs. In gate stacking, the high-k... 相似文献
678.