33 research outputs found
An adaptive sensorimotor representation for reaching in the inferior parietal lobule of behaving monkeys
No full textPrimates use visual guidance in order to interact with their environment. For several decades, the inferior parietal lobule (IPL) has been known to contain neurons that respond to visual stimulation and motor behavior. While the neural activity during the reaching behavior has been shown in area 7a of IPL, reach related neural responses have never been tested in the dorsal prelunate area (DP) of IPL, which is adjacent to area 7a. Furthermore, neural response prior to the reaching movement has not been assessed in DP and area 7a. The first aim was to investigate the tuning properties of single neurons in DP and area 7a. The second aim was to assess the influence of eye position signal on reaching behavior. Third, the temporal evolution of sensorimotor transformation in area 7a and DP neurons was investigated by comparing neural signals throughout the reaching task. Lastly, cortical plasticity was tested using Fresnel prisms, which displaced the visual field by 12º in one of four directions: contralateral, ipsilateral, upwards, or downwards. Foveal and peripheral reaching tasks and reaching under perceptually distorted conditions were used. Neurons in area 7a and DP were observed to have differential tuning properties during the planning phase and the initiation of the reach, in addition to being selective for eye position and retinal visual stimulation. The response properties of the neurons in areas 7a and DP changed as the trial progressed in time. Differential preparatory and reach responses were observed during foveal and peripheral reaching. This implies that both eye position and retinal signals modulated the reach related responses. Alterations in spatial tuning of the neurons during all phases of the task were observed upon insertion of the Fresnel prisms imply that neural plasticity occurs as the cortex swiftly adapts to the mismatch between sensory input and motor output. The spatial tuning of the neurons did not merely compensate for the eye position shift implying that signals other than eye position affect the neural response during reaching. These combined results strongly support the claim that crucial aspects of sensorimotor transformation occur in areas 7a and DP.Ph.D.Includes bibliographical referencesIncludes vitaby Anushree Karni
Selected topics in interventional radiology: a compendium of student honors papers on the Interventional radiology elective
No full textThis book is a collaborative effort with medical students from the Rutgers/Robert Wood Johnson Medical School, previously Robert Wood Johnson Medical School. The students contributed chapters written as honors papers,while on their Interventional Radiology elective. This publication is not meant to completely cover the ever expanding realm of interventional radiology but includes topics of interest to the students while on their elective. It has been rewarding to work with these amazing students, many of whom have elected to practice diagnostic and interventional radiology. This work was supported by a small grant from the Rutgers Library to create affordable books. As it is self published please overlook minor flaws.
The newest area of interventional radiology, interventional oncology, will be covered in subsequent chapters as they are written. As with other dynamic fields of medicine some material becomes outdated soon after it is written. As this is an electronic publication we will strive to update chapters as required.Central venous access in interventional radiology / Daniel Haddad, Mary-Katherine Lynch
Image -guided percutaneous needle biopsy / Ross Cadman
Image -guided percutaneous
abscess drainage of abdominal and pelvic abscess / Zaeem Billah, Dhaval Mehta
Interventional radiology approaches for the treatment of refractory ascites / Travis R. Quinoa
Radial artery access in interventional radiology / Lauren A. Huntress
Segmental arterial mediolysis / Julian Sison
Hemodialysis vascular access, complications, and interventional treatment / Pierre Saad
Non-operative management of splenic injury / Ulyana Trytko
Management of splenic artery aneurysm with coil embolization / Henal Patel
The use of arterial embolization in pelvic trauma / Henal Patel, Rima Patel
Management of massive hemoptysis with bronchial artery embolization / Shreya Amin
Minimally invasive approach
to treating renal angiomyolipoma / Adam Zybulewski
Pulmonary arteriovenous malformations / Ripal Patel, Michael Chevinsky
Radiologic and endoscopic percutaneous gastrostomy: a review of the literature / Fernando D. Arias
Treatment of benign bile duct strictures by balloon dilitation and stent placement / Jason Feinman
Transjugular liver biopsy / Oluwatoyin Dada
Point shear/wave liver elastography / Eric Wei
Renal artery stenosis: medical management vs. percutaneous revascularization / Adjoa Boateng, Gregg Khodorov
Minimally invasive treatment of intrahepatic cholangiocarcinoma / Jaclyn N. Portelli Tremont
Vena cava filters
and the treatment of pulmonary embolism / Anushree Doshi
Interventional treatment of pulmonary embolism / Matthew Deek
Percutaneous access for nephrostomy and nephro-lithotomy / Prasann Vachhani
Portal vein embolization and hepatic hypertrophy / Kristin Maletsky
THe role of interventional radiology in upper GI and colonic hemorrhage
contemporary management and outcomes / Slavamir Sokalaw
Small intestinal bleeding / Oren Johnson
Gastrointestinal hemorrhage aorto-enteric fistula / Hansol Kim
Management of non-variceal upper gastrointestinal bleeding in patients with liver cirrhosis / Vikram Rajpurohit
Transjugular intrahepatic portosystemic shunt / Na Eun Kim
Review and analysis of balloon-occluded retrograde transvenous obliteration (BRTO ) vs. transjugular intrahepatic porto-systemic shunt (TIPS) procedures as a treatment for gastric varices / Iqra Farooqi , Kiersten Frenchu
The value of multi-detector helical CT (MDCT) scans in evaluating acute gastro-intestinal bleeding"September 2020
1637 Spectrum of cases of inborn errors of immunity and their clinical and laboratory profile: a case series from a tertiary care hospital in South India
No full textCombined stent-retriever and aspiration intra-arterial thrombectomy performance for fragmentable blood clots: A proof-of-concept computational study
No full textMechanical thrombectomy (MT) treatment of acute ischemic stroke (AIS) patients typically involves use of stent retrievers or aspiration catheters alone or in combination. For in silico trials of AIS patients, it is crucial to incorporate the possibility of thrombus fragmentation during the intervention. This study focuses on two aspects of the thrombectomy simulation: i) Thrombus fragmentation on the basis of a failure model calibrated with experimental tests on clot analogs; ii) the combined stent-retriever and aspiration catheter MT procedure is modeled by adding both the proximal balloon guide catheter and the distal access catheter. The adopted failure criterion is based on maximum principal stress threshold value. If elements of the thrombus exceed this criterion during the retrieval simulation, then they are deleted from the calculation. Comparison with in-vitro tests indicates that the simulation correctly reproduces the procedures predicting thrombus fragmentation in the case of red blood cells rich thrombi, whereas non-fragmentation is predicted for fibrin-rich thrombi. Modeling of balloon guide catheter prevents clot fragments' embolization to further distal territories during MT procedure.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomechatronics & Human-Machine ControlMedical Instruments & Bio-Inspired Technolog
The creative potential of women: A Reading of Ambai’s A Kitchen in the Corner of the House
Get PDFS. Lakshmi is an Indian writer who is widely known for her short stories in Tamil. She writes under the pseudonym Ambai. Born in Coimbatore, Tamil Nadu in 1944, Ambai calls herself a “feminist who has lived without compromise.’ Apart from feminist fiction, the Tamil author has been carrying out research in the field of women’s studies. Her brand of feminism has earned her recognition in literary circles in both India and abroad. Her important research projects include Illustrated Social History of Women in Tamil Nadu and An Idiom of Silence: An Oral History and Pictoral Study.The resulting research has been published as two volumes of theSeven seas & Seven mountainsseries. The first volume, The Singer and the Song (2000), is a collection of interviews with women musicians and the second volume, Mirrors and Gestures (2003), is a collection of interviews with women dancers. Her popular fictional works include A Purple Sea (1992) and In A Forest, A Deer (2006). Lakshmi Holmstrom has translated some of her works into English.
Ambai’s works articulate the experience of women in a colloquial language using multiple narratives. She shows her characters negotiating with the external world to seek freedom of mind and spirit. She demonstrates how patriarchal forces are present even in their absence and exercise an invisible control over the minds of women in the families. She also highlights how freedom cannot be sought by rebellion but by gradually dismantling the confining structures.
 
Effect of Autoclaving on Flexibility of Four Different Nickel Titanium Files
Get PDFIntroduction: Nickel-titanium (NiTi) files, introduced over 2 decades ago, have the unique property of superelasticity, are more resistant to fracture and are more flexible than stainless steel files. Recent developments in NiTi include M wire and Controlled/Thermal Memory Technology resulting in files with claimed superior properties to conventional NiTi files. Manufacturers recommend sterilization of files prior to usage. These files may be subjected to further autoclaving if reused. The purpose of this study was to test the effect of multiple cycles of autoclaving on the flexibility of four brands of NiTi files and to evaluate differences between brands. Materials and Methods: HyFlex CM (Coltene Whaldent) [sic], Vortex, Profile and Vortex Blue (Dentsply Tulsa Dental Specialties) files of size 35 with 0.04 taper were selected for this study. All files were subjected to 0, 1, 3 and 5 cycles of autoclaving and their flexibility was assessed with cantilever bending at 37oC (n=20/brand/cycles). Non-autoclaved files were used as controls. Two-way ANOVA and Post Hoc Tukey\u27s test were used to assess the differences in flexibility. Results: Autoclaving had no significant (p\u3e0.05) effect on the flexibility within a given file brand but there were significant (p Profile \u3e Vortex \u3e Vortex Blue. Conclusion: Autoclaving had no effect on the mechanical properties of these NiTi rotary files
Indirect detection of dark matter at INO
No full textNeutrino fluxes arising from WIMP annihilation in the center of the sun(), earth() and galaxy can leave detectable signatures at the proposed 50-kt Iron Calorimeter (ICAL) detector at the upcoming India-Based Neutrino Observatory (INO). Although the atmospheric neutrinos will pose a serious background to such signal neutrinos, exploiting the excellent angular resolution of the ICAL detector we can suppress it considerably. The expected 90 % C.L. exclusion sensitivity limits for 500 kt-years exposure for channel (100 % branching ratio) for WIMP-nucleon Spin Dependent () and Spin Independent () cross-section are found to be cm and cm for the WIMP mass () = 25 GeV, and for =52.14 GeV
Prospects of indirect searches for dark matter at INO
No full textThe annihilation of Weakly Interactive Massive Particles (WIMP) in the centre of the sun could give rise to neutrino fluxes. We study the prospects of searching for these neutrinos at the upcoming Iron CALorimeter (ICAL) detector to be housed at the India-based Neutrino Observatory (INO). We perform ICAL simulations to obtain the detector efficiencies and resolutions in order to simulate muon events in ICAL due to neutrinos coming from annihilation of WIMP in the mass range m(chi) = (3 - 100) GeV. The atmospheric neutrinos pose a major background for these indirect detection studies and can be reduced using the fact that the signal comes only from the direction of the sun. For a given WIMP mass, we find the opening angle theta(90) such that 90 % of the signal events are contained within this angle and use this cone-cut criteria to reduce the atmospheric neutrino background. The reduced background is then weighted by the solar exposure function at INO to obtain the final background spectrum for a given WIMP mass. We perform a chi(2) analysis and present expected exclusion regions in the sigma(SD) - m(chi) and sigma(SI) - m(chi), where sigma(SD) and sigma(SI) are the WIMP-nucleon Spin-Dependent (SD) and Spin-Independent (SI) scattering cross-section, respectively. For a 10 years exposure and m(chi) = 25 GeV, the expected 90 % C. L. exclusion limit is found to be sigma(SD) < 6.87 x 10(-41) cm(2) and sigma(SI) < 7.75 x 10(-43) cm(2) for the tau(+) tau(-) annihilation channel and sigma(SD) < 1.14 x 10(-39) cm(2) and sigma(SI) < 1.30 x 10(-41) cm(2) for the b (b) over bar channel, assuming 100 % branching ratio for each of the WIMP annihilation channel.</p
Evaluation and Mitigation of Power System Oscillations Arising from High Solar Penetration
Get PDFabstract: An important operating aspect of all transmission systems is power system stability
and satisfactory dynamic performance. The integration of renewable resources in general, and photovoltaic resources in particular into the grid has created new engineering issues. A particularly problematic operating scenario occurs when conventional generation is operated at a low level but photovoltaic solar generation is at a high level. Significant solar photovoltaic penetration as a renewable resource is becoming a reality in some electric power systems. In this thesis, special attention is given to photovoltaic generation in an actual electric power system: increased solar penetration has resulted in significant strides towards meeting renewable portfolio standards. The impact of solar generation integration on power system dynamics is studied and evaluated.
This thesis presents the impact of high solar penetration resulting in potentially
problematic low system damping operating conditions. This is the case because the power system damping provided by conventional generation may be insufficient due to reduced system inertia and change in power flow patterns affecting synchronizing and damping capability in the AC system. This typically occurs because conventional generators are rescheduled or shut down to allow for the increased solar production. This problematic case may occur at any time of the year but during the springtime months of March-May, when the system load is low and the ambient temperature is relatively low, there is the potential that over voltages may occur in the high voltage transmission system. Also, reduced damping in system response to disturbances may occur. An actual case study is considered in which real operating system data are used. Solutions to low damping cases are discussed and a solution based on the retuning of a conventional power system stabilizer is given in the thesis.Dissertation/ThesisMasters Thesis Electrical Engineering 201
Effect of Soil Replacement Option on Surface Deflections for Expansive Clay Profiles
Get PDFabstract: Urbanization and infrastructure development often brings dramatic changes in the surface and groundwater regimes. These changes in moisture content may be particularly problematic when subsurface soils are moisture sensitive such as expansive soils. Residential foundations such as slab-on ground may be built on unsaturated expansive soils and therefore have to resist the deformations associated with change in moisture content (matric suction) in the soil. The problem is more pronounced in arid and semi arid regions with drying periods followed by wet season resulting in large changes in soil suction. Moisture content change causes volume change in expansive soil which causes serious damage to the structures. In order to mitigate these ill effects various mitigation are adopted. The most commonly adopted method in the US is the removal and replacement of upper soils in the profile. The remove and replace method, although heavily used, is not well understood with regard to its impact on the depth of soil wetting or near-surface differential soil movements. In this study the effectiveness of the remove and replace method is studied. A parametric study is done with various removal and replacement materials used and analyzed to obtain the optimal replacement depths and best material. The depth of wetting and heave caused in expansive soil profile under climatic conditions and common irrigation scenarios are studied for arid regions. Soil suction changes and associated soil deformations are analyzed using finite element codes for unsaturated flow and stress/deformation, SVFlux and SVSolid, respectively. The effectiveness and fundamental mechanisms at play in mitigation of expansive soils for remove and replace methods are studied, and include (1) its role in reducing the depth and degree of wetting, and (2) its effect in reducing the overall heave potential, and (3) the effectiveness of this method in pushing the seat of movement deeper within the soil profile to reduce differential soil surface movements. Various non-expansive replacement layers and different surface flux boundary conditions are analyzed, and the concept of optimal depth and soil is introduced. General observations are made concerning the efficacy of remove and replace as a mitigation method.Dissertation/ThesisPh.D. Civil and Environmental Engineering 201
