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Sample records for partial surgery experimental

  1. Partially coherent interferometric biometry in cataract surgery

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Findl, Oliver; Menapace, Rupert; Hitzenberger, Christoph K.; Fercher, Adolf F.

    1999-02-01

    In an earlier study we showed that precise axial eye length measurement on cataract eyes is possible with the dual beam partial coherence interferometry technique (PCI). A high correlation with the standard ultrasound technique has been obtained. Recently, in a prospective study, partially coherent interferometry and ultrasound biometry were compared in cataract surgery using the SRK II formula based on US applanation biometry. Three months after surgery PCI was repeated and refractive outcome was determined. The use of PCI would have improved refractive outcome by about 30%.

  2. Cellular proliferation after experimental glaucoma filtration surgery

    SciTech Connect

    Jampel, H.D.; McGuigan, L.J.; Dunkelberger, G.R.; L'Hernault, N.L.; Quigley, H.A.

    1988-01-01

    We used light microscopic autoradiography to determine the time course of cellular incorporation of tritiated thymidine (a correlate of cell division) following glaucoma filtration surgery in seven eyes of four cynomolgus monkeys with experimental glaucoma. Incorporation of tritiated thymidine was detected as early as 24 hours postoperatively. Peak incorporation occurred five days postoperatively and had returned to baseline levels by day 11. Cells incorporating tritiated thymidine included keratocytes, episcleral cells, corneal and capillary endothelial cells, and conjunctival and corneal epithelial cells. Transmission electron microscopy was correlated with the autoradiographic results to demonstrate that fibroblasts were dividing on the corneoscleral margin. These findings have potential clinical implications for the use of antiproliferative agents after filtration surgery.

  3. Achieving zero ischemia in minimally invasive partial nephrectomy surgery.

    PubMed

    Hou, Weibin; Ji, Zhigang

    2015-06-01

    Widespread application of the minimally invasive partial nephrectomy (MIPN) techniques like laparoscopic and robotic partial nephrectomy, has been limited by concerns about prolonged warm ischemia. So techniques aiming at performing have been actively explored. A systemic review of literatures on the MIPN without hilar clamping was performed and related methods were summarized. There are mainly seven methods including selective/segmental renal artery clamping technique, selective renal parenchymal clamping technique, targeted renal blood flow interruption technique, laser supported MIPN, radio frequency assisted MIPN, hydro-jet assisted MIPN, and sequential preplaced suture renorrhaphy technique that have been undergoing enthusiastic investigation for achieving MINP without hilar clamping. All of these emerging techniques represent the exploring work to achieve a zero ischemia MIPN for small renal tumors of different characteristics. Though not perfect for any of the technique, they deserve a further assessment during their future experimental and clinical applications. PMID:25895732

  4. Diode laser supported partial nephrectomy in laparoscopic surgery: preliminary results

    NASA Astrophysics Data System (ADS)

    Sroka, Ronald; Hennig, Georg; Zillinberg, Katja; Khoder, Wael Y.

    2011-07-01

    Introduction: Warm ischemia and bleeding during laparoscopic partial nephrectomy place technical constraints on surgeons. Therefore it was the aim to develop a safe and effective laser assisted partial nephrectomy technique without need for ischemia. Patients and methods: A diode laser emitting light at 1318nm in cw mode was coupled into a bare fibre (core diameter 600 μm) thus able to transfer up to 100W to the tissue. After dry lab experience, a total of 8 patients suffering from kidney malformations underwent laparoscopic/retroperitoneoscopic partial nephrectomy. Clinically, postoperative renal function and serum c-reactive protein (CRP) were monitored. Laser induced coagulation depth and effects on resection margins were evaluated. Demographic, clinical and follow-up data are presented. Results: Overall interventions, the mean operative time was 116,5 minutes (range 60-175min) with mean blood loss of 238ml (range 50-600ml) while laser assisted resection of the kidney tissue took max 15min. After extirpation of the tumours all patients showed clinical favourable outcome during follow up period. The tumour size was measured to be 1.8 to 5cm. With respect to clinical safety and due to blood loos, two warm ischemia (19 and 24min) must be performed. Immediate postoperative serum creatinine and CRP were elevated within 0.1 to 0.6 mg/dl (mean 0.18 mg/dl) and 2.1-10 mg/dl (mean 6.24 mg/dl), respectively. The depth of the coagulation on the removed tissue ranged between <1 to 2mm without effect on histopathological evaluation of tumours or resection margin. As the surface of the remaining kidney surface was laser assisted coagulated after removal. The sealing of the surface was induced by a slightly larger coagulation margin, but could not measured so far. Conclusion: This prospective in-vivo feasibility study shows that 1318nm-diode laser assisted partial nephrectomy seems to be a safe and promising medical technique which could be provided either during open surgery

  5. [Partial onychectomy and plastic surgery as treatment of ingrown nails].

    PubMed

    Briziarelli, P; Moretti, M; Barbetti, G; Pasquini, F

    1982-05-26

    The Authors report on a technique for a preserving treatment of the ingrowing nail, by means of partial onycectomy associated with plastic repair of soft tissues of the surrounding nail bed. PMID:7088382

  6. Experimental demonstration of a secondary source of partially polarized states.

    PubMed

    Barberena, D; Gatti, G; De Zela, F

    2015-04-01

    We present a simple device that works as a secondary source of light with prescribed polarization properties. The device has great versatility, allowing complete control over both the degree of polarization and the Stokes vector that belongs to the fully polarized component of partially polarized light beams. We report experimental results that illustrate the device's versatility, by showing how polarized states can be moved within the Poincaré ball along spiraling paths. PMID:26366781

  7. Magnetic Navigation System for Thoracoscopic Surgery: a Partial Lung Resection with Transbronchial Marking

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Itoh, Kazuhiro; Terauchi, Kunihiko; Yanada, Masashi; Shimomura, Masanori; Nishikawa, Atsushi

    In order to detect and track a small magnet embedded in the vicinity of a target tumor during surgery, we have developed a magnetic navigation system based on three-dimensional measurements with micro-fluxgate magnetic sensors. In this paper, we present an image overlay method for superimposing the embedded magnetic marker through a bronchoscope. To evaluate the performance of the proposed system and its applicability in clinical use, we set up an in vivo experiment, in which surgeons used this system to perform thoracoscopic surgery on a pig with transbronchial marking and oblique-viewing, and we succeeded in a partial resection of the pig lung including the target area. Next, we tried a wedge resection for a lung tumor in a clinical case. We successfully performed the partial resection of the lung including the target area, which corresponded to the tumor lesion, under the guidance of the magnetic navigation system.

  8. Partial discharge in a high voltage experimental test assembly

    SciTech Connect

    Koss, R.J.; Brainard, J.P.

    1998-07-01

    This study was initiated when a new type of breakdown occurred in a high voltage experimental test assembly. An anomalous current pulse was observed, which indicated partial discharges, some leading to total breakdowns. High voltage insulator defects are shown along with their effect on the electrostatic fields in the breakdown region. OPERA electromagnetic field modeling software is used to calculate the fields and present a cause for the discharge. Several design modifications are investigated and one of the simplest resulted in a 25% decrease in the field at the discharge surface.

  9. Digital approach to planning computer-guided surgery and immediate provisionalization in a partially edentulous patient.

    PubMed

    Arunyanak, Sirikarn P; Harris, Bryan T; Grant, Gerald T; Morton, Dean; Lin, Wei-Shao

    2016-07-01

    This report describes a digital approach for computer-guided surgery and immediate provisionalization in a partially edentulous patient. With diagnostic data obtained from cone-beam computed tomography and intraoral digital diagnostic scans, a digital pathway of virtual diagnostic waxing, a virtual prosthetically driven surgical plan, a computer-aided design and computer-aided manufacturing (CAD/CAM) surgical template, and implant-supported screw-retained interim restorations were realized with various open-architecture CAD/CAM systems. The optional CAD/CAM diagnostic casts with planned implant placement were also additively manufactured to facilitate preoperative inspection of the surgical template and customization of the CAD/CAM-fabricated interim restorations. PMID:26868961

  10. Experimental evidence supports mantle partial melting in the asthenosphere.

    PubMed

    Chantel, Julien; Manthilake, Geeth; Andrault, Denis; Novella, Davide; Yu, Tony; Wang, Yanbin

    2016-05-01

    The low-velocity zone (LVZ) is a persistent seismic feature in a broad range of geological contexts. It coincides in depth with the asthenosphere, a mantle region of lowered viscosity that may be essential to enabling plate motions. The LVZ has been proposed to originate from either partial melting or a change in the rheological properties of solid mantle minerals. The two scenarios imply drastically distinct physical and geochemical states, leading to fundamentally different conclusions on the dynamics of plate tectonics. We report in situ ultrasonic velocity measurements on a series of partially molten samples, composed of mixtures of olivine plus 0.1 to 4.0 volume % of basalt, under conditions relevant to the LVZ. Our measurements provide direct compressional (V P) and shear (V S) wave velocities and constrain attenuation as a function of melt fraction. Mantle partial melting appears to be a viable origin for the LVZ, for melt fractions as low as ~0.2%. In contrast, the presence of volatile elements appears necessary to explaining the extremely high V P/V S values observed in some local areas. The presence of melt in LVZ could play a major role in the dynamics of plate tectonics, favoring the decoupling of the plate relative to the asthenosphere. PMID:27386548

  11. Experimental evidence supports mantle partial melting in the asthenosphere

    PubMed Central

    Chantel, Julien; Manthilake, Geeth; Andrault, Denis; Novella, Davide; Yu, Tony; Wang, Yanbin

    2016-01-01

    The low-velocity zone (LVZ) is a persistent seismic feature in a broad range of geological contexts. It coincides in depth with the asthenosphere, a mantle region of lowered viscosity that may be essential to enabling plate motions. The LVZ has been proposed to originate from either partial melting or a change in the rheological properties of solid mantle minerals. The two scenarios imply drastically distinct physical and geochemical states, leading to fundamentally different conclusions on the dynamics of plate tectonics. We report in situ ultrasonic velocity measurements on a series of partially molten samples, composed of mixtures of olivine plus 0.1 to 4.0 volume % of basalt, under conditions relevant to the LVZ. Our measurements provide direct compressional (VP) and shear (VS) wave velocities and constrain attenuation as a function of melt fraction. Mantle partial melting appears to be a viable origin for the LVZ, for melt fractions as low as ~0.2%. In contrast, the presence of volatile elements appears necessary to explaining the extremely high VP/VS values observed in some local areas. The presence of melt in LVZ could play a major role in the dynamics of plate tectonics, favoring the decoupling of the plate relative to the asthenosphere. PMID:27386548

  12. Development of reformative surgery method using partial freezing for the liver.

    PubMed

    Takahashi, M; Nomura, S; Jindai, M; Shibata, S; Zhu, X; Watanabe, Y; Kawachi, K; Okabe, N

    2006-12-01

    To minimize surgical stresses including blood loss and operation time to the patients during hepatic resection, we studied the feasibility of a combination of a partial liver freezing technique and shape-memory alloy, which also enables a free-designed resection curve. In this surgical procedure, the region surrounding a tumor in the liver is frozen to excise and prevent hemorrhage. The liver was frozen by a Peltier module. The effects of cooling rate and freezing temperature on the excision force that arise between a scalpel and the liver are carried out experimentally as a basic research for partial freezing surgical procedures. A porcine liver was used as a liver sample. The physical properties were estimated by using the finite element method based on the heat transfer characteristics of the liver. Isolation of the liver was conducted using a scalpel attached to the end-effector of a 3 degrees of freedom robot. In the experiments, the minimum excision force was obtained at a temperature between 272 K and 275 K; therefore, it is preferable that the liver be excised within this temperature range. Lowering of the cooling rate decreases the excision force even if the temperature of the liver remains unchanged. The lower the temperature of the liver is, the larger the increment rate of excision force is with regard to the cooling rate. PMID:17154687

  13. Computer-assisted virtual treatment planning combined with flapless surgery and immediate loading in the rehabilitation of partial edentulies

    PubMed Central

    DE VICO, G.; SPINELLI, D.; BONINO, M.; SCHIAVETTI, R.; POZZI, A.; OTTRIA, L.

    2012-01-01

    SUMMARY It has been suggested that for success with immediate loaded dental implants it is necessary that, prior to their placement, bone quality and quantity as well as the biomechanical environment in which the implants are to function be evaluated. However, conventional techniques currently used for immediate implant placement lack sufficient precision and are usually accomplished by opening flap procedures. Nowadays computer-guided flapless surgery for implant placement using stereolithographic templates is gaining popularity among clinicians and patients. The advantages of this surgical protocol are its minimally invasive nature, accuracy of implant placement, predictability, less post-surgical disconfort and reduced time required for definitive rehabilitation. The introduction of digital planning programs has made it possible to place dental implants in preplanned positions and being immediately functionally loaded by using prefabricated prostheses. The surgical guide is used, infact, to develop a master model and fabricate the provisional bridge that will be secured to the implants immediately after their placement using the guided surgery template. In this way patients are able to achieve, in the same day of the surgery, a comfortable fixed rehabilitation needing only minor occlusal adjustments. Job S. et al during the three-month period, have demonstrated that the average reduction of crestal bone height around the implants placed with flapless surgery (0.06 mm) is not statistically significant, while the average reduction of crestal bone height around the implants placed using flap surgery (0.4 mm) is statistically significant, concluding that the use of stereolithographic appliances in accordance with flapless surgery makes immediate placement of the implants more predictable. However, the documentation of this technique in partial rehabilitations is limited. PURPOSE of this paper is to report the benefit of sophisticated pre-operative diagnostic implant

  14. Comparison of Theory with Experimental Data For a Partially Covered Double-Sandwich Cantilever Beam

    NASA Technical Reports Server (NTRS)

    Chen, Qinghua; Levy, Cesar

    1998-01-01

    In this paper, vibration characteristics of a partially covered, double-sandwich cantilever beam are evaluated experimentally and compared to the theoretical results of Levy and Chen for partially covered beams with and without end mass. The results obtained indicate that the theoretical models serve very well in providing the frequency factors and loss factors for the system being investigated.

  15. The Relationship Between Oxygen Reserve Index and Arterial Partial Pressure of Oxygen During Surgery

    PubMed Central

    Dorotta, Ihab L.; Wells, Briana; Juma, David; Applegate, Patricia M.

    2016-01-01

    BACKGROUND: The use of intraoperative pulse oximetry (Spo2) enhances hypoxia detection and is associated with fewer perioperative hypoxic events. However, Spo2 may be reported as 98% when arterial partial pressure of oxygen (Pao2) is as low as 70 mm Hg. Therefore, Spo2 may not provide advance warning of falling arterial oxygenation until Pao2 approaches this level. Multiwave pulse co-oximetry can provide a calculated oxygen reserve index (ORI) that may add to information from pulse oximetry when Spo2 is >98%. This study evaluates the ORI to Pao2 relationship during surgery. METHODS: We studied patients undergoing scheduled surgery in which arterial catheterization and intraoperative arterial blood gas analysis were planned. Data from multiple pulse co-oximetry sensors on each patient were continuously collected and stored on a research computer. Regression analysis was used to compare ORI with Pao2 obtained from each arterial blood gas measurement and changes in ORI with changes in Pao2 from sequential measurements. Linear mixed-effects regression models for repeated measures were then used to account for within-subject correlation across the repeatedly measured Pao2 and ORI and for the unequal time intervals of Pao2 determination over elapsed surgical time. Regression plots were inspected for ORI values corresponding to Pao2 of 100 and 150 mm Hg. ORI and Pao2 were compared using mixed-effects models with a subject-specific random intercept. RESULTS: ORI values and Pao2 measurements were obtained from intraoperative data collected from 106 patients. Regression analysis showed that the ORI to Pao2 relationship was stronger for Pao2 to 240 mm Hg (r2 = 0.536) than for Pao2 over 240 mm Hg (r2 = 0.0016). Measured Pao2 was ≥100 mm Hg for all ORI over 0.24. Measured Pao2 was ≥150 mm Hg in 96.6% of samples when ORI was over 0.55. A random intercept variance component linear mixed-effects model for repeated measures indicated that Pao2 was significantly related to ORI

  16. Experimental and clinical performance of porous tantalum in orthopedic surgery.

    PubMed

    Levine, Brett Russell; Sporer, Scott; Poggie, Robert A; Della Valle, Craig J; Jacobs, Joshua J

    2006-09-01

    Porous tantalum, a new low modulus metal with a characteristic appearance similar to cancellous bone, is currently available for use in several orthopedic applications (hip and knee arthroplasty, spine surgery, and bone graft substitute). The open-cell structure of repeating dodecahedrons is produced via carbon vapor deposition/infiltration of commercially pure tantalum onto a vitreous carbon scaffolding. This transition metal maintains several interesting biomaterial properties, including: a high volumetric porosity (70-80%), low modulus of elasticity (3MPa), and high frictional characteristics. Tantalum has excellent biocompatibility and is safe to use in vivo as evidenced by its historical and current use in pacemaker electrodes, cranioplasty plates and as radiopaque markers. The bioactivity and biocompatibility of porous tantalum stems from its ability to form a self-passivating surface oxide layer. This surface layer leads to the formation of a bone-like apatite coating in vivo and affords excellent bone and fibrous in-growth properties allowing for rapid and substantial bone and soft tissue attachment. Tantalum-chondrocyte composites have yielded successful early results in vitro and may afford an option for joint resurfacing in the future. The development of porous tantalum is in its early stages of evolution and the following represents a review of its biomaterial properties and applications in orthopedic surgery. PMID:16737737

  17. Experimental demonstration of nonlocal effects in the partial-collapse measurement and reversal process

    SciTech Connect

    Xu Xiaoye; Xu Jinshi; Li Chuanfeng; Zou Yang; Guo Guangcan

    2011-01-15

    We demonstrate experimentally the nonlocal reversal of a partial-collapse quantum measurement of a two-photon entangled state. Both the partial-collapse measurement and the reversal operation are implemented in linear optics with two displaced Sagnac interferometers, characterized by single-qubit quantum-process tomography. The recovered state is measured by quantum-state tomography, and its nonlocality is characterized by testing the Bell inequality. Our result will be helpful in quantum communication and quantum error correction.

  18. Biomechanical testing in experimental surgery by laser holography

    NASA Astrophysics Data System (ADS)

    Podbielska, Halina; Kasprzak, Henryk T.; Pennig, Dietmar

    1990-06-01

    Of all the capabilities of holography for image processing and measuring purposes, holographic interferometry has found the broadest application in biological and medical research. As a technique, which is non-destructive and allows for high resolving deformation analysis, holographic interferometry has gained popularity over the recent years in experimental biomechanics and orthopaedics. Some examples of holographic interferometry in experimental orthopaedics are reviewed in this report. The possibility of using holographic interferometry to study the behaviour of broken bones supported by fixing devices is pointed out in this review.

  19. Thyroid surgery with a harmonic scalpel: an experimental study

    PubMed Central

    Dequanter, Didier; Lammens, Martin; Nagy, Nathalie; Shahla, Mohammad; Deniz, Yasmine; Aubert, Christine; Vanhemelrijck, Youri; Lothaire, Philippe

    2016-01-01

    Background The goal of the study was to determinate the safety of the harmonic scalpel, widely used in thyroidectomy, near the recurrent laryngeal nerve (RLN). Methods The study involved ten pigs of either sex. Twenty RLNs at risk were dissected using the new harmonic scalpel FOCUS. The distances between the nerve and the activated instrument were checked with a millimeter ruler. After dissection, the pigs were euthanized, and both RLNs were fixed in formol and examined by histology after staining with hematoxylin–eosin. Due to technical reasons, only 18 RLNs from the ten pigs could be examined. Results In the experiment that investigated the extent of heat injury, ultrasonic dissection did not cause any immediate damage of the nerve even close to the RLN (1 mm away from the RLN). Conclusion The use of harmonic scalpel FOCUS for thyroid surgery is safe for the surrounding structures (nerves). Careful tissue applications of the device near the RLN (1 mm) did not cause any lesion histologically. PMID:27354833

  20. Experimental study of flow due to an isolated suction hole and a partially plugged suction slot

    NASA Technical Reports Server (NTRS)

    Goglia, G. L.; Wilkinson, S. P.

    1980-01-01

    Details for construction of a model of a partially plugged, laminar flow control, suction slot and an isolated hole are presented. The experimental wind tunnel facility and instrumentation is described. Preliminary boundary layer velocity profiles (without suction model) are presented and shown to be in good agreement with the Blasius laminar profile. Recommendations for the completion of the study are made. An experimental program for study of transition on a rotating disk is described along with preliminary disturbance amplification rate data.

  1. Vascular grafts in microvascular surgery. An experimental study

    SciTech Connect

    Marrangoni, A.G.; Marcelli, G.; Culig, M.; Simone, S.T.

    1988-02-01

    The patency of microvascular grafts depends on the luminal diameter, which is determined by the amount of fibrin and platelets deposited on the intraluminal surface and the anastomotic site, and the extent of pseudointimal formation. An experimental microvascular model in rats has been developed in our laboratory using Indium-111-labeled platelets to measure the amount of deposition on grafts inserted into the infrarenal aorta. This study was designed to assess the patency rates in these grafts and the pathologic maturation as determined by light and electron microscopy. Our study suggests that substantial patency rates can be achieved in aspirin-treated rats, although there was little influence on the pathologic maturation. Indium-111 oxine-labeled platelets can be used to document platelet aggregation, and the technique can be a valuable adjunct in the study of microvascular grafts.

  2. Experimental studies on the usage possibilities of the holmium laser in cataract surgery

    NASA Astrophysics Data System (ADS)

    Kecik, Tadeusz; Kecik, Dariusz; Kasprzak, Jan; Pratnicki, Antoni; Jankiewicz, Zdzislaw; Zajac, Andrzej

    1996-03-01

    The authors present initial investigations of used holmium laser during experimental cataract surgery. The investigations were performed 'in vitro' and 'in vivo.' The presented results of the experiments show that structure of the lens can be emulsified with the use of the holmium laser.

  3. Uniportal complete video-assisted thoracoscopic surgery lobectomy with partial pulmonary arterioplasty for lung cancer with calcified lymph node

    PubMed Central

    Wang, Guang-Suo; Wang, Jian; Rao, Zhan-Peng; Ding, Guang-Gui

    2015-01-01

    Now, more and more complete video-assisted thoracoscopic surgery (cVATS) surgeons are capable of performing lobectomy by uniportal approach. However, concerns regarding the safety of uniportal procedures for complex cases such as neoadjuvant chemotherapy, bronchial sleeves or vascular reconstructions still remains. As experience with uniportal VATS has increased, its application toward more technically demanding operations has also expanded. This article describes a uniportal cVATS left upper lobectomy with partial pulmonary arterioplasty for lung cancer with calcified lymph nodes. In order to reduce the risk of bleeding, we looped the left main pulmonary artery and applied two-stage maneuvering for left upper lobe (LUL) bronchus, cut the bronchus at the distal end and close the stump using a stapler at the end, which are conducive to maximal safety. PMID:26793361

  4. Deformation of partially molten granite: a review and comparison of experimental and natural case studies

    NASA Astrophysics Data System (ADS)

    Rosenberg, Claudio L.

    2001-05-01

    Experimental and natural investigations of partially molten granite are compared and reviewed. Experiments suggest that deformation of partially molten granite with low-viscosity melt (104 Pa s) exhibits a rheological critical melt percentage (RCMP). In case of high viscosity melts (108 Pa s), however, the relationship between melt fraction and log viscosity of the partially molten granite may be linear. Considerations about viscosity, rheological thresholds, and segregation of natural melts suggest that low-viscosity melt experiments simulate natural conditions more realistically. Therefore, an RCMP is to be expected under natural conditions. Both diffusion creep and dislocation creep may occur under natural conditions, whereas cataclastic flow is only observed under experimental conditions. A melt-induced transition from dislocation creep to diffusion creep occurs under experimental and natural conditions. Melt topology is controlled by the magnitude of differential stress under experimental conditions. If differential stress is higher than ~100-150 MPa, melt pockets are elongate and oriented at a low angle to the maximum compressive stress. In contrast, in nature, melt pockets tend to be oriented subparallel to the foliation plane, i.e., presumably at a high angle to the maximum compressive stress.

  5. Observation and partial targeted surgery in the management of tympano-jugular paraganglioma: a contribution to the multioptional treatment.

    PubMed

    Mazzoni, Antonio; Zanoletti, Elisabetta

    2016-03-01

    The objective of this study was to assess the value of a limited tumor excision in tympano-jugular paragangliomas treated with observation with the goal of preventing, or repairing, a neural (VII cranial nerve) or brain damage and continue an otherwise correct observation. This is a retrospective case review. Each patient was submitted to a complete neuro-radiological work-up for diagnosis including CT, MRI, and angiography if needed of tympano-jugular paraganglioma class C. All the cases were submitted to observation and in 16 cases partial targeted surgery was performed. In 10 cases, the procedure involved a targeted removal of the tumor growing in contact with, or invading, the Fallopius. In four cases, the procedure was a petro-occipital trans-sigmoid approach to remove the intradural portion of tumor producing the picture of brain stem compression. In two cases, there was the excision of the bleeding tumor surfaces in the outer ear canal. Follow-up ranged from 4 to 20 years. Success was considered the maintenance of observation without the change of class of tumor extension. In 13 over 16 cases, the observation could be continued, as it still was the more favorable option between natural and surgical morbidity. In the other three cases, a newly installed paralysis of the 9-10 cranial nerves due to tumor growth involved a correction of the strategy to a radical procedure. Partial targeted surgery was directed to cases submitted to observation. It allowed to prevent, or repair, an impending, or actual damage to the facial nerve or the brain stem and to continue the abstentional treatment by keeping the balance between natural and therapy morbidity in favor of observation. PMID:25822289

  6. Ancillary procedures necessary for translational research in experimental craniomaxillofacial surgery

    PubMed Central

    Al Rakan, Mohammed; Shores, Jaimie T.; Bonawitz, Steve; Santiago, Gabriel; Christensen, Joani M.; Grant, Gerald; Murphy, Ryan J.; Basafa, Ehsan; Armand, Mehran; Otovic, Pete; Eller, Sue; Brandacher, Gerald; Gordon, Chad R.

    2014-01-01

    Introduction Swine are often regarded as having analogous facial skeletons to humans and therefore serve as an ideal animal model for translational investigation. However, there's a dearth of literature describing the pertinent ancillary procedures required for craniomaxillofacial research. With this in mind, our objective was to evaluate all necessary procedures required for peri-operative management and animal safety related to experimental craniomaxillofacial surgical procedures such as orthotopic, maxillofacial transplantation. Methods Miniature swine (n=9) were used to investigate peri-operative airway management, methods for providing nutrition, and long-dwelling intravenous access. Flap perfusion using near-infrared laser angiography and facial nerve assessment with EMG were explored. Results Bivona(R) tracheostomy was deemed appropriate versus Shiley since soft, wire-reinforced tubing reduced the incidence of tracheal necrosis. PEG tube, as opposed to esophagostomy, provided a reliable route for post-operative feeding. Femoral venous access with dorsal tunneling proved to be an ideal option being far from pertinent neck vessels. Laser angiography was beneficial for real-time evaluation of graft perfusion. Facial EMG techniques for tracing capture were found most optimal using percutaneous leads near the oral commissure. Experience shows that ancillary procedures are critical and malpositioning of devices may lead to irreversible sequelae with premature animal death. Conclusion Face-jaw-teeth transplantation in swine is a complicated procedure which demands special attention to airway, feeding, and intravascular access. It is critical that each ancillary procedure be performed by a dedicated team familiar with relevant anatomy and protocol. Emphasis should be placed on secure skin-level fixation for all tube/lines to minimize risk of dislodgement. A reliable veterinarian team is invaluable and critical for long-term success. PMID:25377964

  7. Experimental evaluation of furosemide renography in unobstructed and partially obstructed upper urinary tracts in pigs

    SciTech Connect

    Harving, N.; Christiansen, P.; Taagehoj-Jensen, F.; Frokjaer, J.; Djurhuus, J.C.; Mortensen, J. )

    1991-06-01

    To evaluate the reliability and the constancy of the furosemide renography an experimental evaluation of the test has been performed. A standardized unilateral partial proximal ureteral obstruction was applied to 11 pigs. Preoperatively and again weekly in the three weeks following obstruction a furosemide renogram (FR) was done. The furosemide renography was a very constant parameter in the unobstructed kidney (85%) and in the partly obstructed kidney (85%). A type I FR pattern (O'Reilly classification) was an exact indicator of an unobstructed pelvis. After partial ureteral obstruction, an immediate change in the FR pattern was seen either into type II or type IIIa renography. In this experimental study furosemide renography was found to be a reliable tool in the differentiation between the unobstructed normal renal pelves and the partly obstructed dilated renal pelves.

  8. Non-exposed endoscopic wall-inversion surgery as a novel partial gastrectomy technique.

    PubMed

    Mitsui, Takashi; Niimi, Keiko; Yamashita, Hiroharu; Goto, Osamu; Aikou, Susumu; Hatao, Fumihiko; Wada, Ikuo; Shimizu, Nobuyuki; Fujishiro, Mitsuhiro; Koike, Kazuhiko; Seto, Yasuyuki

    2014-01-01

    In gastric full-thickness resection employing both endoscopy and laparoscopy, intraabdominal contamination or even possibly tumor seeding is unavoidable as a result of iatrogenic perforation and the resultant spread of gastric juice. To minimize contamination and resected tissue volume, we developed a new technique without perforation termed non-exposed endoscopic wall-inversion surgery (NEWS), and present here the preliminary results. In a clinical observation cohort study, NEWS was attempted in six patients with gastric SMT to investigate the procedure, mortality, and morbidity. NEWS consists of several steps: marking around a tumor on the mucosal as well as the serosal surface, submucosal injection of sodium hyaluronate with indigo carmine dye, circumferential seromuscular dissection with suture closure under laparoscopy, and circumferential mucosubmucosal incision under gastric endoscopy. The resected specimen is then retrieved perorally. Perforation occurred as a result of misidentification and technical inadequacy in the first three patients. After modification of the devices, the entire procedure was successfully achieved in the latter three. There were no complications in any of our six cases. NEWS allows en bloc full-thickness resection, theoretically avoiding contamination and tumor dissemination into the peritoneal cavity. PMID:23974429

  9. Production of ferroan andesites by the experimental partial melting of an LL chondrite

    NASA Technical Reports Server (NTRS)

    Mcguire, J. C.; Jurewicz, A. J. G.; Jones, J. H.

    1994-01-01

    A partial melting experiment on the St. Severin (LL) chondrite produced a melt that was andesitic, having 54-60 wt% silica, at 1200 C and an oxygen fugacity of IW+2, two log units above the iron-wustite (IW) buffer. Under these same conditions, CV, CM, and L chondrites produced low-silica melts resembling angrites. This experimental study attempts to reproduce and explain this unusual result.

  10. [Some notes on the history of the experimental surgery laboratory. Reflections on its relevance in education and surgical research].

    PubMed

    de la Garza-Rodea, Anabel Sofía; Padilla-Sánchez, Luis; de la Garza-Aguilar, Javier; Neri-Vela, Rolando

    2007-01-01

    The progress of medicine has largely been due to research, and for surgery, in particular, the experimental surgical laboratory has been considered fundamental to the surgeon's education. In this study, a general view of experimental surgery is given in animal models based on bioethical norms as well as to design, create and apply different surgical procedures before performing in humans. Experimental surgery also facilitates surgical teaching and promotes the surgeon's scientific reasoning. Methods. This is a retrospective and descriptive study. Data were collected from direct and indirect sources of available publications on the historical, bioethical and educational aspects of medicine, focusing on surgery. The important facts corresponding to the field of experimental surgery and applicable in Mexico were selected. Concepts of experimental surgical models and of the experimental surgery laboratory were described. Bioethical considerations are emphasized for care of experimental animals. Finally, this work focuses on the importance of surgical experimentation in current and future development of the surgical researcher. Conclusions. Experimentation with animal models in a surgical laboratory is essential for surgical teaching and promotes development of the scientific thought in the surgeon. It is necessary for surgical research and is fundamental for making progress in surgery, treatment and medicine as science. PMID:18177574

  11. TRANEXAMIC ACID ACTION ON LIVER REGENERATION AFTER PARTIAL HEPATECTOMY: EXPERIMENTAL MODEL IN RATS

    PubMed Central

    SOBRAL, Felipe Antonio; DAGA, Henrique; RASERA, Henrique Nogueira; PINHEIRO, Matheus da Rocha; CELLA, Igor Furlan; MORAIS, Igor Henrique; MARQUES, Luciana de Oliveira; COLLAÇO, Luiz Martins

    2016-01-01

    ABSTRACT Background: Different lesions may affect the liver resulting in harmful stimuli. Some therapeutic procedures to treat those injuries depend on liver regeneration to increase functional capacity of this organ. Aim: Evaluate the effects of tranexamic acid on liver regeneration after partial hepatectomy in rats. Method: 40 rats (Rattus norvegicus albinus, Rodentia mammalia) of Wistar-UP lineage were randomly divided into two groups named control (CT) and tranexamic acid (ATX), with 20 rats in each. Both groups were subdivided, according to liver regeneration time of 32 h or seven days after the rats had been operated. The organ regeneration was evaluated through weight and histology, stained with HE and PCNA. Results: The average animal weight of ATX and CT 7 days groups before surgery were 411.2 g and 432.7 g, and 371.3 g and 392.9 g after the regeneration time, respectively. The average number of mitotic cells stained with HE for the ATX and CT 7 days groups were 33.7 and 32.6 mitosis, and 14.5 and 14.9 for the ATX and CT 32 h groups, respectively. When stained with proliferating cell nuclear antigen, the numbers of mitotic cells counted were 849.7 for the ATX 7 days, 301.8 for the CT 7 days groups, 814.2 for the ATX 32 hand 848.1 for the CT 32 h groups. Conclusion: Tranexamic acid was effective in liver regeneration, but in longer period after partial hepatectomy.

  12. Margin and complication rates in clampless partial nephrectomy: a comparison of open, laparoscopic and robotic surgeries.

    PubMed

    Mearini, Luigi; Nunzi, Elisabetta; Vianello, Alberto; Di Biase, Manuel; Porena, Massimo

    2016-06-01

    In performing partial nephrectomy (PN), surgeons focus on complete removal of tumor, preservation of renal function, the absence of major perioperative complications, expressed by the formula margin, ischemia and complication (MIC). The aim of current study was to perform a single-institution comparison of clampless open (OPN), laparoscopic (LPN) or robot-assisted (RAPN) PN as well as to evaluate pre-, intra- and postoperative factors that may influence achievement of ideal MIC. All consecutive clampless OPN, LPN or RAPN performed by experienced surgeons between 2006 and 2015 were included in the analysis. MIC was defined as negative surgical margin plus zero-ischemia plus absence of any grade ≥3 complications according to Clavien-Dindo classification. Bivariate and multivariate logistic regression models were fitted to predict the MIC. Odds ratios with 95 % confidence intervals were calculated. 80 patients underwent OPN, 66 LPN and 31 RAPN, and both groups had similar characteristics. The MIC rate was 67.5, 86.3 and 83.3 % in the OPN, LPN and RAPN groups, respectively (p = 0.016). At logistic regression analysis, surgical approach (p = 0.03) and operative time (p = 0.008) were independent predictors of the MIC rate. When stratified according to the surgical approach, preoperative aspects and dimensions used for an anatomical classification (PADUA) score, LPN, RAPN and operative time were independent predictors of MIC rate (p = 0.0488, p = 0.0494, p = 0.0479 and p = 0.0108, respectively). Clampless LPN and RAPN have an efficacy and safety profile that is on par with OPN, offering the additional benefits of a reduced operative time, blood loss, on demand ischemia and rate of high-grade complications. PMID:27083923

  13. Prone Accelerated Partial Breast Irradiation After Breast-Conserving Surgery: Compliance to the Dosimetry Requirements of RTOG-0413

    SciTech Connect

    Wen Bixiu; Department of Radiation Oncology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080 ; Hsu, Howard; Formenti-Ujlaki, George F.; Lymberis, Stella; Magnolfi, Chiara; Zhao Xuan; Chang Jenghwa; DeWyngaert, J. Keith; Jozsef, Gabor; Formenti, Silvia C.

    2012-11-15

    Purpose: The dosimetric results from our institution's trials of prone accelerated partial breast irradiation are compared with the dosimetric requirements of RTOG-0413. Methods and Materials: Trial 1 and Trial 2 are 2 consecutive trials of prone-accelerated partial breast irradiation. Eligible for both trials were stage I breast cancer patients with negative margins after breast-conserving surgery. The planning target tumor volume (PTV) was created by extending the surgical cavity 2.0 cm for Trial 1 and 1.5 cm for Trial 2, respectively. Contralateral breast, heart, lungs, and thyroid were contoured. Thirty Gray was delivered in five daily fractions of 6 Gy by a three-dimensional conformal radiation therapy technique in Trial 1 and were by image-guided radiation therapy/intensity-modulated radiation therapy in Trial 2. Dosimetric results from the trials are reported and compared with RTOG 0413 requirements. Results: One hundred forty-six consecutive plans were analyzed: 67 left and 79 right breast cancers. The plans from the trials complied with the required >90% of prescribed dose covering 90% of PTV{sub E}VAL (=generated from the PTV by cropping 0.5 cm from the skin edge and excluding the chest wall): V90% was 98.1 {+-} 3.0% (with V100% and V95%, 89.4 {+-} 12.8%, 96.4 {+-} 5.1%, respectively). No significant difference between laterality was found (Student's t test). The dose constraints criteria of the RTOG-0413 protocol for ipsilateral and contralateral lung (V30 <15% and Dmax <3%), heart (V5 <40%), and thyroid (Dmax <3%) were satisfied because the plans showed an average V5% of 0.6% (range, 0-13.4) for heart, an average V30% of 0.6% (range, 0-9.1%) for ipsilateral lung, and <2% maximum dose to the thyroid. However, our partial breast irradiation plans demonstrated a higher dose to contralateral breast than that defined by RTOG constraints, with a median value of maximum doses of 4.1% (1.2 Gy), possibly as a result of contouring differences. Conclusions: Our

  14. An experimental method for directly determining the interconnectivity of melt in a partially molten system

    NASA Technical Reports Server (NTRS)

    Daines, Martha J.; Richter, Frank M.

    1988-01-01

    An experimental method for directly determining the degree of interconnectivity of melt in a partially molten system is discussed using an olivine-basalt system as an example. Samarium 151 is allowed time to diffuse through mixtures of olivine and basalt powder which have texturally equilibrated at 1350 C and 13 to 15 kbars. The final distribution of samarium is determined through examination of developed radiographs of the samples. Results suggest an interconnected melt network is established at melt fractions at least as low as 1 wt pct and all melt is completely interconnected at melt fractions at least as low as 2 wt pct for the system examined.

  15. Catalytic partial oxidation of iso-octane over rhodium catalysts: An experimental, modeling, and simulation study

    SciTech Connect

    Hartmann, M.; Minh, H.D.; Maier, L.; Deutschmann, O.

    2010-09-15

    Catalytic partial oxidation of iso-octane over a rhodium/alumina coated honeycomb monolith is experimentally and numerically studied at short-contact times for varying fuel-to-oxygen ratios. A new experimental set-up with well-defined inlet and boundary conditions is presented. The conversion on the catalyst and in the gas-phase is modeled by detailed reaction mechanisms including 857 gas-phase and 17 adsorbed species. Elementary-step based heterogeneous and homogeneous reaction mechanisms are implemented into two-dimensional flow field description of a single monolith channel. Experiment and simulation provide new insights into the complex reaction network leading to varying product distribution as function of fuel-to-oxygen ratio. At fuel rich conditions, the formation of by-products that can serve as coke precursors is observed and interpreted. (author)

  16. Experimental Measurement of Frozen and Partially Melted Water Droplet Impact Dynamics

    NASA Technical Reports Server (NTRS)

    Palacios, Jose; Yan, Sihong; Tan, Jason; Kreeger, Richard E.

    2014-01-01

    High-speed video of single frozen water droplets impacting a surface was acquired. The droplets diameter ranged from 0.4 mm to 0.9 mm and impacted at velocities ranging from 140 m/sec to 309 m/sec. The techniques used to freeze the droplets and launch the particles against the surfaces is described in this paper. High-speed video was used to quantify the ice accretion area to the surface for varying impact angles (30 deg, 45 deg, 60 deg), impacting velocities, and break-up angles. An oxygen /acetylene cross-flow flame used to ensure partial melting of the traveling frozen droplets is also discussed. A linear relationship between impact angle and ice accretion is identified for fully frozen particles. The slope of the relationship is affected by impact speed. Perpendicular impacts, i.e. 30 deg, exhibited small differences in ice accretion for varying velocities, while an increase of 60% in velocity from 161 m/sec to 259 m/sec, provided an increase on ice accretion area of 96% at an impact angle of 60 deg. The increase accretion area highlights the importance of impact angle and velocity on the ice accretion process of ice crystals. It was experimentally observed that partial melting was not required for ice accretion at the tested velocities when high impact angles were used (45 and 60 deg). Partially melted droplets doubled the ice accretion areas on the impacting surface when 0.0023 Joules were applied to the particle. The partially melted state of the droplets and a method to quantify the percentage increase in ice accretion area is also described in the paper.

  17. An experimental study of partial melting and fractional crystallization on the HED parent body

    NASA Astrophysics Data System (ADS)

    Ashcroft, Helen O.; Wood, Bernard J.

    2015-11-01

    We have performed an experimental and modeling study of the partial melting behavior of the HED parent body and of the fractional crystallization of liquids derived from its mantle. We estimated the mantle composition by assuming chondritic ratios of refractory lithophile elements, adjusting the Mg# and core size to match the density and moment of inertia of Vesta, and the compositions of Mg-rich olivines found in diogenites. The liquidus of a mantle with Mg# (=100*[Mg/(Mg+Fe)]) 80 is ~1625 °C and, under equilibrium conditions, the melt crystallizes olivine alone until it is joined by orthopyroxene at 1350 °C. We synthesized the melt from our 1350 °C experiment and simulated its fractional crystallization path. Orthopyroxene crystallizes until it is replaced by pigeonite at 1200 °C. Liquids become eucritic and crystal assemblages resemble diogenites below 1250 °C. MELTS correctly predicts the olivine liquidus but overestimates the orthopyroxene liquidus by ~70 °C. Predicted melt compositions are in reasonable agreement with those generated experimentally. We used MELTS to determine that the range of mantle compositions that can produce eucritic liquids and diogenitic solids in a magma ocean model is Mg# 75-80 (with chondritic ratios of refractory elements). A mantle with Mg# ~ 70 can produce eucrites and diogenites through sequential partial melting.

  18. Custom prefabrication of silicone tubes from urinary catheters for experimental peripheral nerve surgery.

    PubMed

    Saray, Aydin

    2004-01-01

    The entubulation principle represents a neurobiological approach to nerve surgery in which the role of the surgeon is limited and intrinsic healing capabilities of the nerve play the primary role. Herein, a technique for fabricating custom-made silicone tubes from a silicone urinary catheter is described. Silicone tubes with varying size and dimensions can be tailored depending on the diameter of the silicone urinary catheter (14 F to 18 F). Tubes crafted from silicone urinary catheters were used either as a nerve conduit to facilitate regeneration or as compressive nerve banding to simulate compressive neuropathy in the rat sciatic nerve. Custom-made silicone tubes have similar pros and cons to the commercially available silicone tubes regarding the capsule and foreign body reaction. It can be concluded that these cost effective tubes can be easily cut and used in experimental peripheral nerve surgery in developing countries where the cost of such materials becomes an important issue for the researchers. PMID:24115867

  19. Bulk and shear viscosities of partially molten rocks: Experimental approach using analogue material

    NASA Astrophysics Data System (ADS)

    Suzuki, A. M.; Watanabe, S.; Takei, Y.

    2012-12-01

    Deformation of partially molten rock has two types: shear deformation and compaction/decompaction. The former is controlled by shear viscosity, and the latter by bulk viscosity. While shear viscosity has been measured extensively, relatively few experimental studies have investigated bulk viscosity (Renner et al., 2003). Bulk viscosity and its ratio to shear viscosity, ξ/η, play an important role in melt segregation dynamics (Katz, 2008). Most numerical studies has used the theoretically predicted value of ξ/η~φ-1, where φ is the melt fraction. However, Takei and Holtzman (2009) theoretically obtained a value of ξ/η=1.7 by taking into account a diffusion creep mechanism. The discrepancy between two models is significant at small φ. To discuss the validity of these models based on the experimental data, it is highly important to measure both bulk and shear viscosities by using identical samples. In this study, we measured experimentally bulk and shear viscosities as functions of melt fraction using a partially molten rock analogue. Samples were polycrystalline aggregates of borneol-diphenylamine binary with eutectic temperature of 316K, which has a quite similar equilibrium microstructure to olivine + basalt system (Takei, 2000). Initial melt fraction can be controlled precisely by the amount of diphenylamine because of its simple eutectic reaction. Before deformation experiments, samples were annealed at 320K for ~100 hours in a sealed capsule to make those grain size large enough (~30μm), resulted in negligible grain growth during the successive deformation tests at the same temperature. To measure the bulk and shear viscosities, we carried out two separate experiments. For bulk viscosity, we performed compaction experiments in which melt was squeezed from the partially molten sample. A cylindrical sample contacted with porous metals at the top and bottom ends was compacted uniaxially in a rigid sleeve (ɛzz ≠ 0, ɛxx = ɛyy = 0). Melt can flow out

  20. Experimental model for bone regeneration in oral and cranio-maxillo-facial surgery.

    PubMed

    Mardas, Nikos; Dereka, Xanthippi; Donos, Nikolaos; Dard, Michel

    2014-02-01

    Bone and tooth loss, as a result of trauma, anatomical or congenital reasons, cancer, and periodontal disease, is a common therapeutic problem in the fields of cranio-maxillo-facial surgery and periodontics. The proposed techniques for the treatment of various bone defects encountered include bone grafts, bone substitutes, guided tissue regeneration, and distraction osteogenesis as well as their combinations. In addition, dental implants have been successfully utilized for the restoration of full or partial edentulism. The introduction and development of new therapeutic approaches and devices demand the use of appropriate animal models that present bone anatomy and healing comparable to human. Among other animal models, the pig is extensively documented in several biomedical areas and has been largely used in maxillo-facial surgery and implants dentistry-related research. Anatomical and physiological similarities with human in size, physiology, and bone biology contribute to a successful involvement of this animal to understand and treat various osseous lesions. However, improvements and standardization are requested with respect to consistency and discrimination abilities. The aim of this review is to provide a critical appraisal of the literature related to swine models for the evaluation of cranio-maxillo-facial osseous defect healing, regeneration, and bone-implant interface. This review should assist researchers in the field to select the most appropriate model for each dedicated purpose and also contribute to stimulate an innovative thinking on the use of porcine models. PMID:23957784

  1. Hazard of CO₂ laser-induced airway fire in laryngeal surgery: experimental data of contributing factors.

    PubMed

    Stuermer, Konrad Johannes; Ayachi, Stefan; Gostian, Antoniu-O; Beutner, Dirk; Hüttenbrink, Karl-Bernd

    2013-09-01

    In carbon dioxide (CO2) laser surgery of the larynx, the potentially dangerous combination of laser-induced heat in an oxygen-enriched atmosphere typically occurs when jet ventilation is used or due to an insufficiently blocked endotracheal tube. Until now, no limitations for safe oxygen concentrations or laser intervals have been established. The aim of this study was to investigate and quantify the factors that may contribute to an airway fire in laryngeal laser surgery. Fat, muscle and cartilage were irradiated with a CO2 laser at 2, 4, 6 and 8 W in five different oxygen concentrations with and without smoke exhaustion. The time to ignition was recorded for each different experimental setup. Fat burnt fastest, followed by cartilage and muscle. The elevation of laser energy or oxygen concentration reduced the time to inflammation of any tissue. The elevation of oxygen by 10 % increases the risk of inflammation more than the elevation of laser power by 2 W. Under smoke exhaustion, inflammation and burning occurred delayed or were even inhibited at lower oxygen concentrations. Lasing in more than 50 % oxygen is comparatively dangerous and can cause airway fire in less than 5 s, especially when laser energies of more than 5 W are applied. In equal or lower than 50 % oxygen, an irradiation interval of 5 s can be considered a comparatively safe time limit to prevent inflammation in laryngeal laser surgery. Smoke exhaustion should always be applied. PMID:23636479

  2. Experimental deformation of partially molten granite and implications for strain localization

    NASA Astrophysics Data System (ADS)

    Goncalves, L.; Hirth, G.; Alkmim, F.; Pedrosa-Soares, A.; Goncalves, C.

    2011-12-01

    To improve our understanding of partially molten systems we conducted a set of hydrostatic, general shear and axial compression experiments on sintered aggregates composed of equal amounts by weight of quartz, albite and microcline (grain size of 37-53μm). All experiments were conducted using a Griggs solid medium apparatus at T=900°C, P=1.5GPa and strain rates from 10-4/s to 10-6/s. Previous hydrostatic and axial compression experiments conducted on partial molten granitic rocks have shown that the initial grain size, amount of melt and strain rate are important parameters for the development of distinct microstructures, LPO, and melt distribution. In addition, some of these studies demonstrated that the strength of granite and aplite decrease significantly for melt contents up to 15%, when compared to similar melt-free rocks. The rock's strength deep within the Earth decreases owing to partial melting which brings up some questions: would strain localization take place when partial melt affects rheology? Would brittle and/or ductile shear zones act as potential regions for concentration of partial melt? Is there a critical fraction of melt responsible for strain localization? How is melt distribution influenced by deformation? How does the kinematics of deformation (i.e., axial compression versus general shear) affect melt distribution? The purpose of our experiments is to investigate the role of melting on the rheological properties of crustal rocks. In addition, we seek to provide new constraints on the grain scale processes that control the properties of partially molten rocks and the importance of these processes in understanding shear localization in the lithosphere. Samples were made from crushed Amelia albite (Ab97Or2An1), Hugo Microcline (Or90) and Black Hills quartzite, which have all been used in previous experimental deformation studies. The albite is essentially pure; the microcline contains ~ 1% of muscovite. The Black Hills quartzite contains < 1

  3. Computer-guided implant surgery and immediate loading with a modifiable radiographic template in a patient with partial edentulism: A clinical report.

    PubMed

    Lanis, Alejandro; Padial-Molina, Miguel; Gamil, Rami; Alvarez del Canto, Orlando

    2015-09-01

    Computer-guided implant surgery in fresh extraction sites is an underdeveloped procedure. The presence of teeth that will be extracted makes the creation of an appropriate radiographic template for virtual simulation of the rehabilitation impossible. A modified radiographic template is presented to define a digital restorative simulation for the maxillary rehabilitation of a patient with partial edentulism. This modification enables 3-dimensional prosthetic virtual information in regions where teeth will be extracted. PMID:26013068

  4. Experimental identification and study of hydraulic resonance test rig with Francis turbine operating at partial load

    NASA Astrophysics Data System (ADS)

    Favrel, A.; Landry, C.; Müller, A.; Avellan, F.

    2012-11-01

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of amplitude pressure fluctuations by hydro-acoustic models breaks down and gives unreliable results. A more detailed knowledge of the eigenmodes and a better understanding of phenomenon occurring at resonance could allow improving the hydro-acoustic models prediction.This paper presents an experimental identification of a resonance observed in a close-looped hydraulic system with a Francis turbine reduced scale model operating at partial load. The resonance is excited matching one of the test rig eigenfrequencies with the vortex rope precession frequency. At this point, the hydro-acoustic response of the test rig is studied more precisely and used finally to reproduce the shape of the excited eigenmode.

  5. Experimental test of the viscous anisotropy hypothesis for partially molten rocks

    PubMed Central

    Qi, Chao; Kohlstedt, David L.; Katz, Richard F.; Takei, Yasuko

    2015-01-01

    Chemical differentiation of rocky planets occurs by melt segregation away from the region of melting. The mechanics of this process, however, are complex and incompletely understood. In partially molten rocks undergoing shear deformation, melt pockets between grains align coherently in the stress field; it has been hypothesized that this anisotropy in microstructure creates an anisotropy in the viscosity of the aggregate. With the inclusion of anisotropic viscosity, continuum, two-phase-flow models reproduce the emergence and angle of melt-enriched bands that form in laboratory experiments. In the same theoretical context, these models also predict sample-scale melt migration due to a gradient in shear stress. Under torsional deformation, melt is expected to segregate radially inward. Here we present torsional deformation experiments on partially molten rocks that test this prediction. Microstructural analyses of the distribution of melt and solid reveal a radial gradient in melt fraction, with more melt toward the center of the cylinder. The extent of this radial melt segregation grows with progressive strain, consistent with theory. The agreement between theoretical prediction and experimental observation provides a validation of this theory. PMID:26417107

  6. Experimental test of the viscous anisotropy hypothesis for partially molten rocks.

    PubMed

    Qi, Chao; Kohlstedt, David L; Katz, Richard F; Takei, Yasuko

    2015-10-13

    Chemical differentiation of rocky planets occurs by melt segregation away from the region of melting. The mechanics of this process, however, are complex and incompletely understood. In partially molten rocks undergoing shear deformation, melt pockets between grains align coherently in the stress field; it has been hypothesized that this anisotropy in microstructure creates an anisotropy in the viscosity of the aggregate. With the inclusion of anisotropic viscosity, continuum, two-phase-flow models reproduce the emergence and angle of melt-enriched bands that form in laboratory experiments. In the same theoretical context, these models also predict sample-scale melt migration due to a gradient in shear stress. Under torsional deformation, melt is expected to segregate radially inward. Here we present torsional deformation experiments on partially molten rocks that test this prediction. Microstructural analyses of the distribution of melt and solid reveal a radial gradient in melt fraction, with more melt toward the center of the cylinder. The extent of this radial melt segregation grows with progressive strain, consistent with theory. The agreement between theoretical prediction and experimental observation provides a validation of this theory. PMID:26417107

  7. Design and Experimental Performance of a Two Stage Partial Admission Turbine, Task B.1/B.4

    NASA Technical Reports Server (NTRS)

    Sutton, R. F.; Boynton, J. L.; Akian, R. A.; Shea, Dan; Roschak, Edmund; Rojas, Lou; Orr, Linsey; Davis, Linda; King, Brad; Bubel, Bill

    1992-01-01

    A three-inch mean diameter, two-stage turbine with partial admission in each stage was experimentally investigated over a range of admissions and angular orientations of admission arcs. Three configurations were tested in which first stage admission varied from 37.4 percent (10 of 29 passages open, 5 per side) to 6.9 percent (2 open, 1 per side). Corresponding second stage admissions were 45.2 percent (14 of 31 passages open, 7 per side) and 12.9 percent (4 open, 2 per side). Angular positions of the second stage admission arcs with respect to the first stage varied over a range of 70 degrees. Design and off-design efficiency and flow characteristics for the three configurations are presented. The results indicated that peak efficiency and the corresponding isentropic velocity ratio decreased as the arcs of admission were decreased. Both efficiency and flow characteristics were sensitive to the second stage nozzle orientation angles.

  8. Experimental Spinel Standards for Ferric Iron (Fe3+) Determination During Peridotite Partial Melting

    NASA Astrophysics Data System (ADS)

    Wenz, M. D.; Sorbadere, F.; Rosenthal, A.; Frost, D. J.; McCammon, C. A.

    2014-12-01

    The presence of ferric iron (Fe3+) in the mantle plays a significant role in the oxygen fugacity (fO2) of the Earth's interior. This has a wide range of implications for Earth related processes ranging from the composition of the atmosphere to magmatic phase relations during melting and crystallization processes [1]. A major source of Earth's mantle magmas is spinel peridotite. Despite its low abundance, spinel (Fe3+/ƩFe = 15-34%, [2]) is the main contributor of Fe3+to the melt upon partial melting. Analyses of Fe3+ on small areas of spinel and melt are required to study the Fe3+ behavior during partial melting of spinel peridotite. Fe K-edge X-ray Absorption Near Edge Structure (XANES) combines both high precision and small beam size, but requires standards with a wide range of Fe3+ content to obtain good calibration. Glasses with varying Fe3+ content are easily synthesized [3, 4]. Spinel, however, presents a challenge for experimental standards due to the low diffusion of Cr and Al preventing compositional homogeneity. Natural spinel standards are often used, but only cover a narrow Fe3+ range. Thus, there is a need for better experimental spinel standards over a wider range of fO2. Our study involves making experimental mantle spinels with variable Fe3+ content. We used a sol-gel auto-combustion method to synthesize our starting material [5]. FMQ-2, FMQ+0, and air fO2 conditions were established using a gas mixing furnace. Piston cylinder experiments were performed at 1.5GPa, and 1310 -1370°C to obtain solid material for XANES. To maintain distinct oxidizing conditions, three capsules were used: graphite for reduced, Re for intermediate and AuPd for oxidized conditions. The spinels were analyzed by Mössbauer spectroscopy. Fe3+/ƩFe ranged from 0.3 to 0.6. These values are consistent with the Fe edge position obtained using XANES analyses, between 7130 and 7132 eV, respectively. Our spinels are thus suitable standards for Fe3+ measurements in peridotite

  9. Impact of textural anisotropy on syn-kinematic partial melting of natural gneisses: an experimental approach.

    NASA Astrophysics Data System (ADS)

    Ganzhorn, Anne-Céline; Trap, Pierre; Arbaret, Laurent; Champallier, Rémi; Fauconnier, Julien; Labrousse, Loic; Prouteau, Gaëlle

    2015-04-01

    Partial melting of continental crust is a strong weakening process controlling its rheological behavior and ductile flow of orogens. This strength weakening due to partial melting is commonly constrained experimentally on synthetic starting material with derived rheological law. Such analog starting materials are preferentially used because of their well-constrained composition to test the impact of melt fraction, melt viscosity and melt distribution upon rheology. In nature, incipient melting appears in particular locations where mineral and water contents are favorable, leading to stromatic migmatites with foliation-parallel leucosomes. In addition, leucosomes are commonly located in dilatants structural sites like boudin-necks, in pressure shadows, or in fractures within more competent layers of migmatites. The compositional layering is an important parameter controlling melt flow and rheological behavior of migmatite but has not been tackled experimentally for natural starting material. In this contribution we performed in-situ deformation experiments on natural rock samples in order to test the effect of initial gneissic layering on melt distribution, melt flow and rheological response. In-situ deformation experiments using a Paterson apparatus were performed on two partially melted natural gneissic rocks, named NOP1 & PX28. NOP1, sampled in the Western Gneiss Region (Norway), is biotite-muscovite bearing gneiss with a week foliation and no gneissic layering. PX28, sampled from the Sioule Valley series (French Massif Central), is a paragneiss with a very well pronounced layering with quartz-feldspar-rich and biotite-muscovite-rich layers. Experiments were conducted under pure shear condition at axial strain rate varying from 5*10-6 to 10-3 s-1. The main stress component was maintained perpendicular to the main plane of anisotropy. Confining pressure was 3 kbar and temperature ranges were 750°C and 850-900°C for NOP1 and PX28, respectively. For the 750

  10. Theoretical and experimental investigation of thermohydrologic processes in a partially saturated, fractured porous medium

    SciTech Connect

    Green, R.T.; Manteufel, R.D.; Dodge, F.T.; Svedeman, S.J.

    1993-07-01

    The performance of a geologic repository for high-level nuclear waste will be influenced to a large degree by thermohydrologic phenomena created by the emplacement of heat-generating radioactive waste. The importance of these phenomena is manifest in that they can greatly affect the movement of moisture and the resulting transport of radionuclides from the repository. Thus, these phenomena must be well understood prior to a definitive assessment of a potential repository site. An investigation has been undertaken along three separate avenues of analysis: (i) laboratory experiments, (ii) mathematical models, and (iii) similitude analysis. A summary of accomplishments to date is as follows. (1) A review of the literature on the theory of heat and mass transfer in partially saturated porous medium. (2) A development of the governing conservation and constitutive equations. (3) A development of a dimensionless form of the governing equations. (4) A numerical study of the importance and sensitivity of flow to a set of dimensionless groups. (5) A survey and evaluation of experimental measurement techniques. (6) Execution of laboratory experiments of nonisothermal flow in a porous medium with a simulated fracture.

  11. Pain management in pigs undergoing experimental surgery; a literature review (2012-4).

    PubMed

    Bradbury, A G; Eddleston, M; Clutton, R E

    2016-01-01

    Failure to provide effective analgesia to animals in noxious studies contravenes the obligation to refine animal experimentation and, by increasing 'noise' in physiological data sets, may decrease the scientific validity of results. Pig models of surgical conditions are becoming increasingly important and used for translational work. This review aimed to determine the extent to which the recent biomedical literature describes pain assessment and alleviation in pigs recovering from experimental surgery. Three databases (Medline, Web of Knowledge, and Google Scholar) were searched to find relevant studies published from January 2012 to March 2014. Information on pain assessment and peri- and postoperative analgesia was extracted. The review identified 233 papers meeting selection criteria. Most articles (193/233, 83%) described use of drugs with analgesic properties, but only 87/233 (37%) described postoperative analgesia. No article provided justification for the analgesic chosen, despite the lack of guidelines for analgesia in porcine surgical models and the lack of formal studies on this subject. Postoperative pain assessment was reported in only 23/233 (10%) articles. It was found that the reporting of postoperative pain management in the studies was remarkably low, reflecting either under-reporting or under-use. Analgesic description, when given, was frequently too limited to enable reproducibility. Development of a pain-scoring system in pigs, together with the mandatory description of pain management in submitted articles, would contribute to improved laboratory pig welfare. PMID:26433866

  12. Bevacizumab-Loaded Polyurethane Subconjunctival Implants: Effects on Experimental Glaucoma Filtration Surgery

    PubMed Central

    Ribeiro, Vanessa Raquel Coimbra; Chahud, Fernando; Cannellini, Roberta; Monteiro, Tassia Cristina; de Lima Gomes, Elionai Cassiana; Reinach, Peter Sol; Veronese Rodrigues, Maria de Lourdes; Silva-Cunha, Armando

    2013-01-01

    Abstract Purpose Vascular endothelial growth factor (VEGF) may contribute to the scarring process resulting from glaucoma filtration surgery, since this cytokine may stimulate fibroblast proliferation. The aim of this study was to describe a new bevacizumab-loaded polyurethane implant (BPUI) and to evaluate its effectiveness as a new drug delivery system of anti-VEGF antibody in a rabbit model of glaucoma filtration surgery. Methods An aqueous dispersion of polyurethane was obtained via the conventional process. Bevacizumab (1.5 mg) was then incorporated into the dispersion and was subsequently dried to form the polymeric films. Films with dimensions of 3×3×1 mm that either did (group BPUI, n=10) or did not contain bevacizumab (group PUI, n=10) were implanted in the subconjunctival space, at the surgical site in 1 eye of each rabbit. The in vitro bevacizumab release was evaluated using size-exclusion high-performance liquid chromatography (HPLC), and the in vivo effects of the drug were investigated in a rabbit experimental trabeculectomy model by examining the bleb characteristics and collagen accumulation, and by performing immunohistological analyses of VEGF expression. Results HPLC showed that only 10% of the bevacizumab in the implants had been released by postoperative day 5. In vivo studies demonstrated that the drug had no adverse effects; however, no significant differences in either the bleb area score or the collagen deposit intensity between the group PUI and the group that BPUI were observed. Moreover, the group BPUI presented a significantly lower proportion of VEGF-expressing fibroblasts than group PUI (0.17±0.03 vs. 0.35±0.05 cells/field, P=0.005). Conclusions This study demonstrated that bevacizumab release from the BPUIs only occurred for a short time probably from the surface of the films. Nevertheless, they were well tolerated in rabbit eyes and reduced the number of VEGF-expressing fibroblasts. PMID:23391327

  13. A correlational and experimental examination of reality television viewing and interest in cosmetic surgery.

    PubMed

    Markey, Charlotte N; Markey, Patrick M

    2010-03-01

    Two studies are presented that examine the influence of media messages about cosmetic surgery on youths' interest in altering their own physical appearance. In Study 1, 170 participants (59% female; M age=19.77 years) completed surveys assessing their impression of reality television shows featuring cosmetic surgery, appearance satisfaction, self-esteem, and their interest in cosmetic surgery. Results indicated that participants who reported favorable impressions of reality television shows featuring cosmetic surgery were more likely to indicate interest in pursuing surgery. One hundred and eighty-nine participants (51% female; M age=19.84 years) completed Study 2. Approximately half of the participants were exposed to a television message featuring a surgical make-over; the other half was exposed to a neutral message. Results indicated that participants who watched a television program about cosmetic surgery wanted to alter their own appearance using cosmetic surgery more than did participants who were not exposed to this program. PMID:20089464

  14. Experimental investigation on ignition schemes of partially covered cavities in a supersonic flow

    NASA Astrophysics Data System (ADS)

    Cai, Zun; Sun, Mingbo; Wang, Hongbo; Wang, Zhenguo

    2016-04-01

    In this study, ignition schemes of the partially covered cavity in a scramjet combustor were investigated under inflow conditions of Ma=2.1 with stagnation pressure P0=0.7 Mpa and stagnation temperature T0=947 K. It reveals that the ignition scheme of the partially covered cavity has a great impact on the ignition and flame stabilization process. There always exists an optimized global equivalence ratio of a fixed ignition scheme, and the optimized global equivalence ratio of ignition in the partially covered cavity is lower than that of the uncovered cavity. For tandem dual-cavities, ignition in the partially covered cavity could be enhanced with the optimization of global equivalence ratio. However, ignition in the partially covered cavity would be exacerbated with further increasing the global equivalence ratio. The global equivalence ratio and the jet penetration height have a strong coupling with the combustion flow-field. For multi-cavities, it is assured that fuel injection on the opposite side could hardly be ignited after ignition in the partially covered cavity even with the optimized global equivalence ratio. It is possible to realize ignition enhancement in the partially covered cavity with the optimization of global equivalence ratio, but it is not beneficial for thrust increment during the steady combustion process.

  15. Experimental Hydrous Partial Melting of Natural Pristine and Altered MORB Beneath Subduction Zones

    NASA Astrophysics Data System (ADS)

    Carter, L. B.; Skora, S. E.; Blundy, J.

    2012-12-01

    Experimental determination of the hydrous phase relations and trace element partitioning behaviour of Mid-Ocean Ridge Basalt (MORB) constrains the conditions for melting of subducted oceanic crust. This study utilises natural pristine MORB (from the Kolbeinsey ridge, north of Iceland) and altered MORB from the altered oceanic crust (AOC, from the DSDP leg 46, Mid Atlantic, ~20°N), hydrated with about 15wt% water, in experiments using piston-cylinder apparatus to simulate pressures and temperatures equivalent to about 100 km depth (3.0 GPa, 800-1000°C). Our motivation of (re-)studying the melting behaviour of undoped subducted basalt is two-fold. First, previous studies that focused on the trace element behaviour 'doped' their starting materials with trace elements to facilitate analysis and positive identification of accessory phases. Only by applying the 'doping' method has it been found that allanite may exert a key control on the light rare earth element (approx. La-Sm) budget in subducted basalt. However, it is still a matter of debate whether the ubiquitous presence of allanite in these experimental studies is solely due to doping of La-Sm. In addition, bulk fluid-solid partition coefficients so obtained may not be uncritically applied to model the trace element transfer in nature because of the enhanced proportions of accessory phases in the experimental solid residue. Second, there appears to be a clear difference in the melting behaviour of K-free and K-bearing MORB (and sediment), even if K2O only appears in minor concentrations. These differences are difficult to quantify, as the various studies were carried out at differing P-T-XH2O conditions. In agreement with earlier studies, we find that the vapour-saturated solidus is shifted toward higher temperatures at 3 GPa in pristine MORB (800°C < Tsolidus < 850°C), because it is virtually K-free (approx. 0.03 wt% K2O), in contrast to altered MORB where melting starts at T < 800°C (approx. 0.26 wt% K2O

  16. Petrofabric development during experimental partial melting and recrystallization of a mica-schist analog

    NASA Astrophysics Data System (ADS)

    Almqvist, Bjarne S. G.; Biedermann, Andrea R.; Klonowska, Iwona; Misra, Santanu

    2015-10-01

    Magnetic properties and the anisotropy of magnetic susceptibility (AMS) present promising methods to track mineral orientation and petrofabric in rocks that have undergone partial melting. In order to better understand the source of the magnetic signal in these types of rocks, the interpretation of field observations may be integrated with laboratory experiments, designed to recreate conditions of partial melting. A set of experiments is presented in this study, where synthetic foliated quartz-muscovite aggregates undergo partial melting at 300 MPa hydrostatic confining pressure and 750°C. Magnetic properties and AMS are measured before and after partial melting. Prior to partial melting, the synthetic aggregate shows a compaction-related oblate magnetic fabric, dominated by paramagnetic muscovite that contains small amounts of iron. Post experiment samples show neoblasts that crystallize from incongruent melt reactions. Most notably for the magnetic fabric, the breakdown of muscovite results in growth of secondary phases of Fe-bearing spinel and biotite. Isothermal remanence acquisition and temperature dependence of susceptibility indicate that the spinel is magnetite. The degree of magnetic anisotropy reduces significantly after partial melting, but notably the orientation of the principal axes of susceptibility mimics the AMS of the original quartz-muscovite aggregate. Additionally, the post experiment samples show a relationship between the amount of sample shortening (compaction) and the degree of magnetic anisotropy and susceptibility ellipsoid shape factor. These results suggest that petrofabrics in rocks that undergo partial melting at near hydrostatic pressure conditions may in part be inherited, or mimic, the original petrofabric of a sedimentary or metasedimentary rock.

  17. Experimental validation of A-mode ultrasound acquisition system for computer assisted orthopaedic surgery

    NASA Astrophysics Data System (ADS)

    De Lorenzo, Danilo; De Momi, Elena; Beretta, Elisa; Cerveri, Pietro; Perona, Franco; Ferrigno, Giancarlo

    2009-02-01

    Computer Assisted Orthopaedic Surgery (CAOS) systems improve the results and the standardization of surgical interventions. Anatomical landmarks and bone surface detection is straightforward to either register the surgical space with the pre-operative imaging space and to compute biomechanical parameters for prosthesis alignment. Surface points acquisition increases the intervention invasiveness and can be influenced by the soft tissue layer interposition (7-15mm localization errors). This study is aimed at evaluating the accuracy of a custom-made A-mode ultrasound (US) system for non invasive detection of anatomical landmarks and surfaces. A-mode solutions eliminate the necessity of US images segmentation, offers real-time signal processing and requires less invasive equipment. The system consists in a single transducer US probe optically tracked, a pulser/receiver and an FPGA-based board, which is responsible for logic control command generation and for real-time signal processing and three custom-made board (signal acquisition, blanking and synchronization). We propose a new calibration method of the US system. The experimental validation was then performed measuring the length of known-shape polymethylmethacrylate boxes filled with pure water and acquiring bone surface points on a bovine bone phantom covered with soft-tissue mimicking materials. Measurement errors were computed through MR and CT images acquisitions of the phantom. Points acquisition on bone surface with the US system demonstrated lower errors (1.2mm) than standard pointer acquisition (4.2mm).

  18. Experimental studies on wave interactions of partially perforated wall under obliquely incident waves.

    PubMed

    Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

    2014-01-01

    This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall. PMID:25254260

  19. Experimental Studies on Wave Interactions of Partially Perforated Wall under Obliquely Incident Waves

    PubMed Central

    Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

    2014-01-01

    This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall. PMID:25254260

  20. Generation of felsic melts within fast-spreading oceanic crust: Experimental partial melting of hydrothermally altered sheeted dike

    NASA Astrophysics Data System (ADS)

    Fischer, L. A.; Erdmann, M.; France, L.; Deloule, E.; Koepke, J.

    2013-12-01

    In recent oceanic crust and in ophiolites, felsic lithologies are observed. Different processes, like fractional crystallization of MORB and partial melting of mafic rocks are discussed to form these lithologies. Partial melting is expected as a major process in forming felsic lithologies at the base of the sheeted dike complex of fast-spreading ridges, where the axial melt lens is assumed to be located directly beneath the sheeted dikes.It is widely accepted that this melt lens has the potential to trigger partial melting of mafic lithologies at the gabbro/dike transition zone. In this experimental study, the influence of partial melting on the generation of felsic lithologies is examined. Therefore, partial melting experiments at a pressure of 100 MPa were performed. As starting material, a natural basalt from the IODP (Integrated Ocean Drilling Program) drilling at Site 1256 (equatorial East Pacific Rise) was chosen, which is representative for the lower sheeted dike complex. It is characterized as a moderately altered dolerite containing plagioclase (An50-57), clinopyroxene (Mg# 0.55-0.60) and quartz, with chlorite as secondary phase; sulfides and Fe-Ti-oxides are present as accessory minerals. The partial melting experiments were conducted in an H2-controlled IHPV at the Institute of Mineralogy in Hanover, Germany. To investigate the evolution of the partial melts, different experiments were performed at temperatures between 1030°C and 910°C and a constant pressure of 100 MPa. All experiments were water saturated leading to a fO2 corresponding to QFM +1 (QFM = quartz-fayalite-magnetite oxygen buffer). This is slightly more oxidized than MORB crystallization due to the influence of a hydrous fluid which generally increases the oxygen activity. The experimental products were analyzed using electron microprobe for major elements, and a SIMS (CRPG Nancy, France) for trace elements. We present here our first results on phase relations and mineral compositions

  1. An experimental study of the flow in a wing with a partial span drooped leading edge

    NASA Technical Reports Server (NTRS)

    Winkelmann, A. E.; Tsao, C. P.

    1981-01-01

    The flow field produced by a low aspect ratio wing (AR = 3.0) with a partial span leading edge droop was investigated in a series of low speed wind tunnel tests (Reynolds number based on 17.8 cm chord = 560,000). Photographs were obtained of surface oil flow patterns over an angle of attack range of alpha = 0 to 29 deg. Flow field surveys of the partially stalled wing at alpha = 25 deg were completed using a hot-wire probe, a split-film probe and a Conrad probe. The flow field survey data was presented using a color video display. The data indicated regions of apparent reversed flow in the separation region behind the wing and indicated the general cross-sectional shape of the separated wake flow.

  2. Experimental investigation of gas hydrate formation, plugging and transportability in partially dispersed and water continuous systems

    NASA Astrophysics Data System (ADS)

    Vijayamohan, Prithvi

    As oil/gas subsea fields mature, the amount of water produced increases significantly due to the production methods employed to enhance the recovery of oil. This is true especially in the case of oil reservoirs. This increase in the water hold up increases the risk of hydrate plug formation in the pipelines, thereby resulting in higher inhibition cost strategies. A major industry concern is to reduce the severe safety risks associated with hydrate plug formation, and significantly extending subsea tieback distances by providing a cost effective flow assurance management/safety tool for mature fields. Developing fundamental understanding of the key mechanistic steps towards hydrate plug formation for different multiphase flow conditions is a key challenge to the flow assurance community. Such understanding can ultimately provide new insight and hydrate management guidelines to diminish the safety risks due to hydrate formation and accumulation in deepwater flowlines and facilities. The transportability of hydrates in pipelines is a function of the operating parameters, such as temperature, pressure, fluid mixture velocity, liquid loading, and fluid system characteristics. Specifically, the hydrate formation rate and plugging onset characteristics can be significantly different for water continuous, oil continuous, and partially dispersed systems. The latter is defined as a system containing oil/gas/water, where the water is present both as a free phase and partially dispersed in the oil phase (i.e., entrained water in the oil). Since hydrate formation from oil dispersed in water systems and partially dispersed water systems is an area which is poorly understood, this thesis aims to address some key questions in these systems. Selected experiments have been performed at the University of Tulsa flowloop to study the hydrate formation and plugging characteristics for the partially dispersed water/oil/gas systems as well as systems where the oil is completely dispersed

  3. Prone Accelerated Partial Breast Irradiation After Breast-Conserving Surgery: Five-year Results of 100 Patients

    SciTech Connect

    Formenti, Silvia C.; Hsu, Howard; Fenton-Kerimian, Maria; Roses, Daniel; Guth, Amber; Jozsef, Gabor; Goldberg, Judith D.; DeWyngaert, J. Keith

    2012-11-01

    Purpose: To report the 5-year results of a prospective trial of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation in the prone position. Methods and Materials: Postmenopausal patients with Stage I breast cancer with nonpalpable tumors <2 cm, negative margins and negative nodes, positive hormone receptors, and no extensive intraductal component were eligible. The trial was offered only after eligible patients had refused to undergo standard whole-breast radiotherapy. Patients were simulated and treated on a dedicated table for prone setup. 3D-CRT was delivered at a dose of 30 Gy in five 6-Gy/day fractions over 10 days with port film verification at each treatment. Rates of ipsilateral breast failure, ipsilateral nodal failure, contralateral breast failure, and distant failure were estimated using the cumulative incidence method. Rates of disease-free, overall, and cancer-specific survival were recorded. Results: One hundred patients were enrolled in this institutional review board-approved prospective trial, one with bilateral breast cancer. One patient withdrew consent after simulation, and another patient elected to interrupt radiotherapy after receiving two treatments. Ninety-eight patients were evaluable for toxicity, and, in 1 case, both breasts were treated with partial breast irradiation. Median patient age was 68 years (range, 53-88 years); in 55% of patients the tumor size was <1 cm. All patients had hormone receptor-positive cancers: 87% of patients underwent adjuvant antihormone therapy. At a median follow-up of 64 months (range, 2-125 months), there was one local recurrence (1% ipsilateral breast failure) and one contralateral breast cancer (1% contralateral breast failure). There were no deaths due to breast cancer by 5 years. Grade 3 late toxicities occurred in 2 patients (one breast edema, one transient breast pain). Cosmesis was rated good/excellent in 89% of patients with at least 36

  4. Preoperative estimation of run off in patients with multiple level arterial obstructions as a guide to partial reconstructive surgery.

    PubMed

    Noer, I; Tønnesen, K H; Sager, P

    1978-11-01

    Preoperative measurements of direct femoral artery systolic pressure, indirect ankle systolic pressure and direct brachial artery systolic pressure were carried out in nine patients with severe ischemia and arterial occlusions both proximal and distal to the ingvinal ligament. The pressure-rise at the ankle was estimated preoperatively by assuming that the ankle pressure would rise in proportion to the rise in femoral artery pressure. Thus it was predicted that reconstruction of the iliac obstruction with aorta-femoral pressure gradients from 44 to 96 mm Hg would result in a rise in ankle pressure of 16--54 mm Hg. The actual rise in ankle pressure one month after reconstruction of the iliac arteries ranged from 10 to 46 mm Hg and was well correlated to the preoperative estimations. In conclusion, by proper pressure measurements the run-off problem of multiple level arterial occlusions can be evaluated. Thus the result of successful partial reconstruction can be assessed preoperatively. PMID:718291

  5. Postcorrective surgery improvement of nocturnal hypoxemia in a case of partial anomalous pulmonary venous connection and aberrant hepatic vein drainage

    PubMed Central

    Agrawal, Abhinav; Palkar, Atul V; Sahni, Sonu; Vatsia, Sheel K; Shah, Rakesh D; Talwar, Arunabh

    2016-01-01

    Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital anomaly that leads to an anatomical left-to-right shunt. Termination of the intrahepatic inferior vena cava (IVC) with its azygos continuation associated with the hepatic venous connection to the left atrium (LA) is also a rare congenital anomaly that results in an anatomical right-to-left shunt. A 65-year-old male presented with severe dyspnea on exertion and pedal edema. He was further diagnosed at our clinic and was found to have both the aforementioned congenital abnormalities, creating a bidirectional shunt. On further investigation, he was found to have nocturnal hypoxemia on overnight oximetry. The patient was successfully treated via surgical corrections of the congenital anomalies leading to symptomatic improvement as well as the resolution of nocturnal hypoxemia. PMID:27185995

  6. [Use of mini-septopal in trauma surgery of the hand. Experimental and clinical studies].

    PubMed

    Zimmer, K

    1996-01-01

    The antibiotics application in treatment of infections makes necessary that they are present in the focus of infection in concentration which is enough to fight back bacteria responsible for the symptoms of disease. Concentration higher then MIC is especially difficult to obtain in tissue with poor blood supply.c. in the cortical bone. Many attempts has been made to find proper method to obtain high antibiotic concentration in the infection focus without overloading the rest of the organism. In the years 1972-1973 Klemm in Frankfurt/Main had first very promising results treating bone infections by filling bone cavities after proper surgical debridement with hand-made beads made of bone cement with gentamicin. This method has been developed by the E. MERCK company which started to produce drug as Septopal. Very good results of treatment using this form of antibiotic created natural demand for this method also in hand surgery, where big sized Septopal beads couldn't be used. E. MERCK company has provided us with Septopal Mini Chains where small ellipsoids are gathered in 10- or 20 elements chains. Starting investigations on SMC application the following aims of experimental and clinical studies has been pointed out: observation of tissue reaction for the implanted ellipsoids, studies on gentamicin releasing velocity and its concentration in the implantation site as well as in the tissues of peripheral organs, observation of the potential toxicity and observation of the ellipsoids structure in the scanning electron microscopy, evaluation of usefulness of the SMC in the treatment of bone and soft tissue infections and in prophylactics in high risk wounds treatment, evaluation of its efficiency in comparison with gentamicin-resisted bacterial strains. Statistical analysis of results has proved very high efficiency of this form of drug by obtaining very high local antibiotic concentration even 100 times higher then after parenteral application. No toxic reactions has

  7. Experimental investigation of gas hydrate formation, plugging and transportability in partially dispersed and water continuous systems

    NASA Astrophysics Data System (ADS)

    Vijayamohan, Prithvi

    As oil/gas subsea fields mature, the amount of water produced increases significantly due to the production methods employed to enhance the recovery of oil. This is true especially in the case of oil reservoirs. This increase in the water hold up increases the risk of hydrate plug formation in the pipelines, thereby resulting in higher inhibition cost strategies. A major industry concern is to reduce the severe safety risks associated with hydrate plug formation, and significantly extending subsea tieback distances by providing a cost effective flow assurance management/safety tool for mature fields. Developing fundamental understanding of the key mechanistic steps towards hydrate plug formation for different multiphase flow conditions is a key challenge to the flow assurance community. Such understanding can ultimately provide new insight and hydrate management guidelines to diminish the safety risks due to hydrate formation and accumulation in deepwater flowlines and facilities. The transportability of hydrates in pipelines is a function of the operating parameters, such as temperature, pressure, fluid mixture velocity, liquid loading, and fluid system characteristics. Specifically, the hydrate formation rate and plugging onset characteristics can be significantly different for water continuous, oil continuous, and partially dispersed systems. The latter is defined as a system containing oil/gas/water, where the water is present both as a free phase and partially dispersed in the oil phase (i.e., entrained water in the oil). Since hydrate formation from oil dispersed in water systems and partially dispersed water systems is an area which is poorly understood, this thesis aims to address some key questions in these systems. Selected experiments have been performed at the University of Tulsa flowloop to study the hydrate formation and plugging characteristics for the partially dispersed water/oil/gas systems as well as systems where the oil is completely dispersed

  8. Partitioning of Ni between olivine and siliceous eclogite partial melt: experimental constraints on the mantle source of Hawaiian basalts

    NASA Astrophysics Data System (ADS)

    Wang, Zhengrong; Gaetani, Glenn A.

    2008-05-01

    Olivine is abundant in Earth’s upper mantle and ubiquitous in basaltic lavas, but rarely occurs in eclogite. Partial melts of eclogite are, therefore, not in equilibrium with olivine, and will react with peridotite as they migrate through the upper mantle. If such melts erupt at Earth’s surface, their compositions will be highly modified and they may be olivine-saturated. We investigated experimentally the reaction between olivine and siliceous eclogite partial melt, and determined element partitioning between olivine and the melt produced by this reaction. Our results demonstrate that mixing of reacted eclogite partial melt with primitive basalt is capable of producing the positive correlation between melt SiO2 content and olivine Ni content observed in some Hawaiian lavas. Experiments were carried out by equilibrating eclogite partial melt or basalt with San Carlos olivine at 1 bar and 1,201 1,350°C. Our results show that eclogite partial melts equilibrated with mantle olivine retain their high SiO2, low FeO and MgO characteristics. Further, olivine-melt partition coefficients for Ni measured in these experiments are significantly larger than for basalt. Mixing of these melts with primitive Hawaiian tholeiitic lavas results in crystallization of high-Ni olivines similar to those in Makapuu-stage Koolau lavas, even though the mixed magmas have only moderate Ni contents. This results from a hyperbolic increase of the Ni partition coefficient with increasing polymerization of the mixed melt. Note that while eclogite partial melt in contact with peridotite will equilibrate with pyroxene as well as olivine, this will have the effect of buffering the activity of SiO2 in the reacted melt at a higher level. Therefore, an eclogite partial melt equilibrated with harzburgite will have higher SiO2 than one equilibrated with dunite, enhancing the effects observed in our experiments. Our results demonstrate that an olivine-free “hybrid” pyroxenite source is not

  9. Experimental derivation of nepheline syenite and phonolite liquids by partial melting of upper mantle peridotites

    NASA Astrophysics Data System (ADS)

    Laporte, Didier; Lambart, Sarah; Schiano, Pierre; Ottolini, Luisa

    2014-10-01

    Piston-cylinder experiments were performed to characterize the composition of liquids formed at very low degrees of melting of two fertile lherzolite compositions with 430 ppm and 910 ppm K2O at 1 and 1.3 GPa. We used the microdike technique (Laporte et al., 2004) to extract the liquid phase from the partially molten peridotite, allowing us to analyze liquid compositions at degrees of melting F down to 0.9%. At 1.3 GPa, the liquid is in equilibrium with olivine + orthopyroxene + clinopyroxene + spinel in all the experiments; at 1 GPa, plagioclase is present in addition to these four mineral phases up to about 5% of melting (T≈1240 °C). Important variations of liquid compositions are observed with decreasing temperature, including strong increases in SiO2, Na2O, K2O, and Al2O3 concentrations, and decreases in MgO, FeO, and CaO concentrations. The most extreme liquid compositions are phonolites with 57% SiO2, 20-22% Al2O3, Na2O + K2O up to 14%, and concentrations of MgO, FeO, and CaO as low as 2-3%. Reversal experiments confirm that low-degree melts of a fertile lherzolite have phonolitic compositions, and pMELTS calculations show that the amount of phonolite liquid generated at 1.2 GPa increases from 0.3% in a source with 100 ppm K2O to 3% in a source with 2000 ppm K2O. The enrichment in silica and alkalis with decreasing melt fraction is coupled with an increase of the degree of melt polymerization, which has important consequences for the partitioning of minor and trace elements. Thus Ti4+ in our experiments and, by analogy with Ti4+, other highly charged cations, and rare earth elements become less incompatible near the peridotite solidus. Our study brings a strong support to the hypothesis that phonolitic lavas or their plutonic equivalents (nepheline syenites) may be produced directly by partial melting of upper mantle rock-types at moderate pressures (1-1.5 GPa), especially where large domains of the subcontinental lithospheric mantle has been enriched in

  10. Open partial horizontal laryngectomy for salvage after failure of CO₂ laser-assisted surgery for glottic carcinoma.

    PubMed

    Lucioni, Marco; Bertolin, Andy; Lionello, Marco; Giacomelli, Luciano; Rizzotto, Giuseppe; Marioni, Gino

    2016-01-01

    Total laryngectomy (TL) is often still recommended as a salvage approach for recurrent laryngeal squamous cell carcinoma (LSCC). Considering LSCC recurrences after the failure of primary transoral laser microsurgery (TLM), open partial horizontal laryngectomy (OPHL) could be a valid alternative to TL in selected patients. The aim of the present study was to analyze retrospectively the oncological outcome of a consecutive series of 17 patients treated at the Otolaryngology Unit of Vittorio Veneto Hospital (Italy) with OPHL after primary TLM had failed. Nine patients (53 %) had no further recurrences after salvage OPHL. Eight patients had a second recurrence of LSCC after OPHL, and five of them were cured by further salvage treatment, while the other three died of their disease. We found an overall and disease-specific survival both of 82 % and a loco-regional control rate and an ultimate organ preservation rate of 82 and 70 %, respectively. Patients who underwent two-stage bilateral cordectomy for primary glottic carcinoma showed a trend towards a higher rate of second recurrences, a lower ultimate organ preservation rate and a shorter disease-free survival after salvage OPHL. Further studies on larger cohorts of patients are needed to identify potential clinical and/or pathological prognostic parameters capable of pinpointing patients at higher risk of second recurrences after salvage OPHL in cases where TLM has failed. A salvage TL might be reasonably proposed as a first salvage choice in such cases. PMID:26294221

  11. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients

    PubMed Central

    2016-01-01

    Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results. PMID:27493665

  12. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients.

    PubMed

    Dolcini, Giorgio Andrea; Colombo, Marco; Mangano, Carlo

    2016-01-01

    Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results. PMID:27493665

  13. Experimental Verification of the Kruskal-Shafranov Stability Limit in Line-Tied Partial Toroidal Plasmas

    SciTech Connect

    Oz, E.; Myers, C. E.; Yamada, M.; Ji, H.; Kulsrud, R. M.; Xie, J.

    2011-07-19

    The stability properties of partial toroidal flux ropes are studied in detail in the laboratory, motivated by ubiquitous arched magnetic structures found on the solar surface. The flux ropes studied here are magnetized arc discharges formed between two electrodes in the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys. Plasmas, 4, 1936 (1997)]. The three dimensional evolution of these flux ropes is monitored by a fast visible light framing camera, while their magnetic structure is measured by a variety of internal magnetic probes. The flux ropes are consistently observed to undergo large-scale oscillations as a result of an external kink instability. Using detailed scans of the plasma current, the guide field strength, and the length of the flux rope, we show that the threshold for kink stability is governed by the Kruskal-Shafranov limit for a flux rope that is held fixed at both ends (i.e., qa = 1).

  14. Experimental studies of partially defluidized bed with immersed heat exchange tubes

    NASA Astrophysics Data System (ADS)

    Sitthiphong, N.

    Bed slumping in a partially fluidized bed combustor is modeled in a cold phase fluidized bed. Correlations describing the changing contours of the slumped bed surface are presented. A simple model developed to predict the motions of ejected particles from the active side to the defluidized side of the bed. A method for determining the total amount of bed material transfer at any defluidization time is presented. The effect of superficial velocity on the percentage of gas bypass through the slumped section, on refluidization after a long period of defluidization, on the lateral dispersion coefficient of solids, and on the rate of solids mixing are reported. Results from the model bed were converted to the high temperature case and compared with available data, indicating good agreement of model results with actual data.

  15. Experimental demonstration of optimal universal asymmetric quantum cloning of polarization states of single photons by partial symmetrization

    SciTech Connect

    Cernoch, Antonin; Soubusta, Jan; Celechovska, Lucie; Dusek, Miloslav; Fiurasek, Jaromir

    2009-12-15

    We report on experimental implementation of the optimal universal asymmetric 1->2 quantum cloning machine for qubits encoded into polarization states of single photons. Our linear-optical machine performs asymmetric cloning by partially symmetrizing the input polarization state of signal photon and a blank copy idler photon prepared in a maximally mixed state. We show that the employed method of measurement of mean clone fidelities exhibits strong resilience to imperfect calibration of the relative efficiencies of single-photon detectors used in the experiment. Reliable characterization of the quantum cloner is thus possible even when precise detector calibration is difficult to achieve.

  16. An Experimental Study of Partially Molten Ordinary Chondrite Under Dynamic Conditions: Siderophile Abundances in Quench Fe-S-Ni Liquids

    NASA Astrophysics Data System (ADS)

    Rushmer, T.; Humayun, M.; Campbell, A. J.

    2004-05-01

    from 0.19 at high S contents to 0.56 at low S contents. As goes from compatible to incompatible at approximately 15 wt%\\ S in the liquid. Ir, Ge and Ga show large changes in D as a function of S, ranging from >100 to approximately 1.0 from high to low S content but remain compatible. W and Os remain compatible and range from 1 - 5 and 5 - 7 at 13-15 wt%\\ S and 6-8 wt%\\ S, respectively. We find that the lower temperatures produce Fe-S-Ni liquid compositions observed at higher T in other studies. Part of the difference is likely due to the temperature gradient in the charge, but in addition, deformation may play an important role in enhancing reaction kinetics. The results also show that high sulfur, low degree partial melts have too low Ga, Ge and Ir to form IIE irons. Intermediate degrees of partial melting, represented by melt pools and veins in KM10 and KM17, are closest in composition. The compositional range of experimental melt compositions exceeds the IIE irons observed range. The IIE irons represent a limited portion of the experimental Ni-Co trend, implying generation from a limited range of redox conditions.

  17. Acute inflammatory response to transgastric natural orifice transluminal endoscopic surgery peritoneoscopy: An experimental study in swine

    PubMed Central

    Rezende, Marcelo; Montero, Edna Frasson de Souza; Salomão, Reinaldo; Brunialti, Milena; Rodrigues, Rodrigo; Gomes, Gustavo; Libera, Alice Della; Ferrari, Angelo; Libera, Ermelindo Della

    2013-01-01

    OBJECTIVE: To investigate the impact of transgastric peritoneal access on plasma biomarkers of acute inflammatory response in comparison to laparoscopy. METHODS: This was a prospective and comparative study in a porcine model. Transgastric peritoneal access performed by natural orifice transluminal endoscopic surgery was compared with laparoscopy. Laparotomy and sham groups were used as positive and negative controls, respectively. Thirty-four pigs were assigned to receive transgastric natural orifice transluminal endoscopic surgery (n = 12), laparoscopy (n = 8), laparotomy (n = 8) or a sham procedure involving only anesthesia (n = 6). In the natural orifice transluminal endoscopic surgery group, peritoneoscopy was performed with a gastroscope via transgastric access. Blood samples were collected at baseline and 1, 3, 6, 9 and 24 h after the surgical procedure for measurement of interleukins 1β, 6 and 10 and tumor necrosis factor-α. A complete blood count was performed, and C-reactive protein levels were measured at baseline and at 24 h. RESULTS: All surgical and endoscopic procedures were performed without major complications. Peritoneal cavity inventory showed no signs of peritonitis in any animal. Interleukin 1β, interleukin 10 and tumor necrosis factor-α levels were below the threshold of detection. The mean level of interleukin 6 was statistically significantly higher in the laparotomy group than in the other groups (p<0.05), with no significant differences among the sham, laparoscopy and natural orifice transluminal endoscopic surgery groups (p>0.05). C-reactive protein analysis indicated significant increases in all groups, with no differences among the groups. Complete blood count analysis showed no differences among the groups. CONCLUSIONS: Based on the observed interleukin 6 patterns, the systemic inflammatory response resulting from transgastric peritoneal access by natural orifice transluminal endoscopic surgery is similar in

  18. Blocking Sympathetic Nervous System Reverses Partially Stroke-Induced Immunosuppression but does not Aggravate Functional Outcome After Experimental Stroke in Rats.

    PubMed

    Deng, Qi-Wen; Yang, Heng; Yan, Fu-Ling; Wang, Huan; Xing, Fang-Lan; Zuo, Lei; Zhang, Han-Qing

    2016-08-01

    Stoke results in activation of the sympathetic nervous system (SNS), inducing systemic immunosuppression. However, the potential mechanisms underlying stroke-induced immunosuppression remain unclear. Here, we determined the SNS effects on functional outcome and explored the interactions among SNS, β-arrestin2 and nuclear factor-κB (NF-κB) after experimental stroke in rats. In the current study, stroke was induced by a transient middle cerebral artery occlusion (MCAO) in rats, and SNS activity was inhibited by intraperitoneal injection of 6-hydroxydopamine HBr (6-OHDA). 7.0 T Micro-MRI and Longa score were employed to assess the functional outcome after stroke. Flow cytometry and ELISA assay were used to measure the expression of MHC class II, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Western blot was conducted to analyze β-arrestin2 and NF-κB protein expression levels after experimental stroke. We found significantly increased infarct volumes and functional impairment after MCAO at different post-surgery time points, which were not aggravated by 6-OHDA treatment. SNS blockade partially reversed the expression of MHC class II after stroke over time, as well as TNF-α and IFN-γ levels in lipopolysaccharide-stimulated macrophages in vitro. Treatment of MCAO rats with SNS-inhibitor significantly diminished NF-κB activation and enhanced β-arrestin2 expression after stroke. This study suggests that pharmacological SNS inhibition dose not aggravate functional outcome after stroke. Stroke-induced immunosuppression may be involved in the SNS-β-arrestin2-NF-κB pathway. PMID:27059792

  19. Exogenous collagen cross-linking recovers tendon functional integrity in an experimental model of partial tear.

    PubMed

    Fessel, Gion; Wernli, Jeremy; Li, Yufei; Gerber, Christian; Snedeker, Jess G

    2012-06-01

    We investigated the hypothesis that exogenous collagen cross-linking can augment intact regions of tendon to mitigate mechanical propagation of partial tears. We first screened the low toxicity collagen cross-linkers genipin, methylglyoxal and ultra-violet (UV) light for their ability to augment tendon stiffness and failure load in rat tail tendon fascicles (RTTF). We then investigated cross-linking effects in load bearing equine superficial digital flexor tendons (SDFT). Data indicated that all three cross-linking agents augmented RTTF mechanical properties but reduced native viscoelasticity. In contrast to effects observed in fascicles, methylglyoxal treatment of SDFT detrimentally affected tendon mechanical integrity, and in the case of UV did not alter tendon mechanics. As in the RTTF experiments, genipin cross-linking of SDFT resulted in increased stiffness, higher failure loads and reduced viscoelasticity. Based on this result we assessed the efficacy of genipin in arresting tendon tear propagation in cyclic loading to failure. Genipin cross-linking secondary to a mid-substance biopsy-punch significantly reduced tissue strains, increased elastic modulus and increased resistance to fatigue failure. We conclude that genipin cross-linking of injured tendons holds potential for arresting tendon tear progression, and that implications of the treatment on matrix remodeling in living tendons should now be investigated. PMID:22102295

  20. Four alginate dressings in the treatment of partial thickness wounds: a comparative experimental study.

    PubMed

    Agren, M S

    1996-03-01

    Alginate-based absorption materials for wound treatment are meeting with increasing clinical acceptance. The purpose of this study was to compare four different calcium alginate dressings (Algosteril, Comfeel Alginate, Kaltostat and Sorbsan) with respect to wound fluid retaining ability, adherence, dressing residues, epithelialisation and inflammatory cell infiltration using a standardised partial-thickness wound model in domestic pigs. Wound fluid spread laterally onto surrounding normal skin by about 40% more with Sorbsan than with the other alginate dressings after 24 h of treatment (P = 0.026). The corresponding figure after 66 h of treatment was 20% (P = 0.030). Algosteril (mean 1.7 [sem 0.3]) adhered significantly (P = 0.014) more to the wounds than Comfeel Alginate (mean 0.2 [0.2]). Kaltostat (mean 1.8 [0.3]) left significantly (P = 0.038) more dressing residues on the wound surface at dressing removal than the Comfeel Alginate dressing (mean 0.8 [0.2]). In the effect on epithelialisation or dermal inflammation there was no statistically significant difference at significance level 5% among the four alginate dressings, as assessed by light microscopy. In summary, the four alginate dressings showed significant differences in important handling characteristics and did not differ significantly in their effect on epithelialisation. PMID:8733355

  1. Experimental determination of carbonation rate in Portland cement at 25°C and relatively high CO2 partial pressure

    NASA Astrophysics Data System (ADS)

    Hernández-Rodríguez, Ana; Montegrossi, Giordano; Huet, Bruno; Virgili, Giorgio; Orlando, Andrea; Vaselli, Orlando; Marini, Luigi

    2016-04-01

    The aim of this work is to study the alteration of Portland class G Cement at ambient temperature under a relatively high CO2 partial pressure through suitably designed laboratory experiments, in which cement hydration and carbonation are taken into account separately. First, the hydration process was carried out for 28 days to identify and quantify the hydrated solid phases formed. After the completion of hydration, accompanied by partial carbonation under atmospheric conditions, the carbonation process was investigated in a stirred micro-reactor (Parr instrument) with crushed cement samples under 10 bar or more of pure CO2(g) and MilliQ water adopting different reaction times. The reaction time was varied to constrain the reaction kinetics of the carbonation process and to investigate the evolution of secondary solid phases. Chemical and mineralogical analyses (calcimetry, chemical composition, SEM and X-ray Powder Diffraction) were carried out to characterize the secondary minerals formed during cement hydration and carbonation. Water analyses were also performed at the end of each experimental run to measure the concentrations of relevant solutes. The specific surface area of hydrated cement was measured by means of the BET method to obtain the rates of cement carbonation. Experimental outcomes were simulated by means of the PhreeqC software package. The obtained results are of interest to understand the comparatively fast cement alteration in CO2 production wells with damaged casing.

  2. Characterizing a partially ordered miniprotein through folding molecular dynamics simulations: Comparison with the experimental data.

    PubMed

    Baltzis, Athanasios S; Glykos, Nicholas M

    2016-03-01

    The villin headpiece helical subdomain (HP36) is one of the best known model systems for computational studies of fast-folding all-α miniproteins. HP21 is a peptide fragment-derived from HP36-comprising only the first and second helices of the full domain. Experimental studies showed that although HP21 is mostly unfolded in solution, it does maintain some persistent native-like structure as indicated by the analysis of NMR-derived chemical shifts. Here we compare the experimental data for HP21 with the results obtained from a 15-μs long folding molecular dynamics simulation performed in explicit water and with full electrostatics. We find that the simulation is in good agreement with the experiment and faithfully reproduces the major experimental findings, namely that (a) HP21 is disordered in solution with <10% of the trajectory corresponding to transiently stable structures, (b) the most highly populated conformer is a native-like structure with an RMSD from the corresponding portion of the HP36 crystal structure of <1 Å, (c) the simulation-derived chemical shifts-over the whole length of the trajectory-are in reasonable agreement with the experiment giving reduced χ(2) values of 1.6, 1.4, and 0.8 for the Δδ(13) C(α) , Δδ(13) CO, and Δδ(13) C(β) secondary shifts, respectively (becoming 0.8, 0.7, and 0.3 when only the major peptide conformer is considered), and finally, (d) the secondary structure propensity scores are in very good agreement with the experiment and clearly indicate the higher stability of the first helix. We conclude that folding molecular dynamics simulations can be a useful tool for the structural characterization of even marginally stable peptides. PMID:26609791

  3. Parents influence asymmetric sibling competition: experimental evidence with partially dependent young.

    PubMed

    Smiseth, Per T; Ward, Richard J S; Moore, Allen J

    2007-12-01

    Asymmetric sibling competition, which occurs when some siblings hatch as stronger competitors than others, is an important component of avian reproductive strategies. Here, we report two experiments on the burying beetle Nicrophorus vespilloides investigating how parents might influence the outcome of asymmetric sibling competition. In this species, as in altricial birds, different-aged offspring compete for resources provided by the parents. However, unlike altricial birds, offspring depend only partially on their parents for resources, and parents adjust the brood size directly through filial cannibalism. In the first experiment, we compared the growth and survivorship of different-aged offspring when parents could and could not influence asymmetric sibling competition. In the second experiment, we recorded behavioral interactions between different-aged offspring and parents. We found that senior offspring (early-hatched) grew faster than juniors (late-hatched) when parents were present and could influence the outcome of sibling competition, whereas seniors and juniors grew at similar rates when parents were removed. Thus, seniors benefited more than did juniors when the offspring could obtain resources by begging from the female parent. There was no difference in the survivorship of seniors and juniors. We also found that seniors and juniors spent a similar amount of time feeding from female parents, but juniors spent more time begging and were less effective at begging than seniors. Interestingly, juniors spent more time begging only as long as seniors also begged, suggesting that juniors adjusted their begging effort in response to direct competition against seniors for resources provided by parents. Our study provides novel insights into the ecological significance of asymmetric sibling competition by showing that asymmetric sibling competition took place when parents were present and offspring could obtain resources by begging. In contrast, we found no

  4. Isotopic equilibration during partial melting: an experimental test of the behaviour of Sr

    NASA Astrophysics Data System (ADS)

    Hammouda, T.; Pichavant, M.; Chaussidon, M.

    1996-10-01

    Experiments using isotopically enriched, Sr doped minerals designed to test for isotopic equilibrium between source and melt during partial melting reveal that 87Sr/ 86Sr ratios of the liquids are primarily determined by the proportions of minerals consumed and vary with the advancement of the melting reaction. The experiments were performed at 1 atm on model crustal assemblages composed of pairs of natural plagioclase (An 68; 87Sr/ 86Sr= 0.701 ) and synthetic fluorphlogopite doped with 90 ppm Sr having 87Sr/ 86Sr= 4.2 . SIMS traverses showed that during the initial stages of the reaction, liquids are isotopically zoned. All the analyzed melts have 87Sr/ 86Sr markedly higher than that of the bulk starting assemblage (i.e. the source), because of the faster melting rate of fluorphlogopite. At 1200°C and 1250°C melting occurs above a critical temperature, wherein the dissolution rates of the crystals are controlled by diffusion of species in the melt, and reactants and reaction products are out of isotopic equilibrium. This is due to faster melt-crystal boundary migration when compared to Sr diffusion in the crystals. Equilibration is possible only if melting stops. Calculations show that total equilibration between melt and residue by Sr tracer diffusion in the crystals takes 10 4-10 6 yr (for temperature and grain size ranging, respectively, from 800°C to 1000°C, and 0.1 to 1 cm). When compared to the proposed residence time of crustal magmas at their sources, this result strongly suggests that magmas that do not reflect the bulk isotopic characteristics of their source regions can be produced.

  5. Experimental test of theory for the stability of partially saturated vertical cut slopes

    USGS Publications Warehouse

    Morse, Michael M.; Lu, N.; Wayllace, Alexandra; Godt, Jonathan W.; Take, W.A.

    2014-01-01

    This paper extends Culmann's vertical-cut analysis to unsaturated soils. To test the extended theory, unsaturated sand was compacted to a uniform porosity and moisture content in a laboratory apparatus. A sliding door that extended the height of the free face of the slope was lowered until the vertical cut failed. Digital images of the slope cross section and upper surface were acquired concurrently. A recently developed particle image velocimetry (PIV) tool was used to quantify soil displacement. The PIV analysis showed strain localization at varying distances from the sliding door prior to failure. The areas of localized strain were coincident with the location of the slope crest after failure. Shear-strength and soil-water-characteristic parameters of the sand were independently tested for use in extended analyses of the vertical-cut stability and of the failure plane angle. Experimental failure heights were within 22.3% of the heights predicted using the extended theory.

  6. Partial Sleep Restriction Activates Immune Response-Related Gene Expression Pathways: Experimental and Epidemiological Studies in Humans

    PubMed Central

    Rantanen, Ville; Kronholm, Erkki; Surakka, Ida; van Leeuwen, Wessel M. A.; Lehto, Maili; Matikainen, Sampsa; Ripatti, Samuli; Härmä, Mikko; Sallinen, Mikael; Salomaa, Veikko; Jauhiainen, Matti; Alenius, Harri; Paunio, Tiina; Porkka-Heiskanen, Tarja

    2013-01-01

    Epidemiological studies have shown that short or insufficient sleep is associated with increased risk for metabolic diseases and mortality. To elucidate mechanisms behind this connection, we aimed to identify genes and pathways affected by experimentally induced, partial sleep restriction and to verify their connection to insufficient sleep at population level. The experimental design simulated sleep restriction during a working week: sleep of healthy men (N = 9) was restricted to 4 h/night for five nights. The control subjects (N = 4) spent 8 h/night in bed. Leukocyte RNA expression was analyzed at baseline, after sleep restriction, and after recovery using whole genome microarrays complemented with pathway and transcription factor analysis. Expression levels of the ten most up-regulated and ten most down-regulated transcripts were correlated with subjective assessment of insufficient sleep in a population cohort (N = 472). Experimental sleep restriction altered the expression of 117 genes. Eight of the 25 most up-regulated transcripts were related to immune function. Accordingly, fifteen of the 25 most up-regulated Gene Ontology pathways were also related to immune function, including those for B cell activation, interleukin 8 production, and NF-κB signaling (P<0.005). Of the ten most up-regulated genes, expression of STX16 correlated negatively with self-reported insufficient sleep in a population sample, while three other genes showed tendency for positive correlation. Of the ten most down-regulated genes, TBX21 and LGR6 correlated negatively and TGFBR3 positively with insufficient sleep. Partial sleep restriction affects the regulation of signaling pathways related to the immune system. Some of these changes appear to be long-lasting and may at least partly explain how prolonged sleep restriction can contribute to inflammation-associated pathological states, such as cardiometabolic diseases. PMID:24194869

  7. Experimental test of MR fluid based tactile device for minimally invasive surgery

    NASA Astrophysics Data System (ADS)

    Oh, Jong-Seok; Kim, Jin-Kyu; Choi, Seung-Bok

    2013-04-01

    Recently, it is very popular in modern medical industry to adopt robotic technology such as robotic minimally invasive surgery (RMIS). Compared with open surgery, the RMIS needs the robot to perform surgery through the usage of long surgical instruments that are inserted through incision points. This causes the surgeon not to feel viscosity and stiffness of the tissue or organ. So, for the tactile recognition of human organ in RMIS, this work proposes a novel tactile device that incorporates with magnetorheological (MR) fluid. The MR fluid is fully contained by diaphragm and several pins. By applying different magnetic field, the operator can feel different force from the proposed tactile device. In order to generate required force from the device, the repulsive force of human body is firstly measured as reference data and an appropriate size of tactile device is designed. Pins attached with the diaphragm are controlled by shape-memory-alloy (SMA). Thus, the proposed tactile device can realize repulsive force and shape of organ. It has been demonstrated via experiment whether the measured force can be achieved by applying proper control input current. In addition, psychophysical experiments are conducted to evaluate performance on the tactile rendering of the proposed tactile device. From these results, the practical feasibility of the tactile device is verified.

  8. High-intensity focused ultrasound: advances in technology and experimental trials support enhanced utility of focused ultrasound surgery in oncology

    PubMed Central

    Malietzis, G; Monzon, L; Hand, J; Wasan, H; Leen, E; Abel, M; Muhammad, A; Abel, P

    2013-01-01

    High-intensity focused ultrasound (HIFU) is a rapidly maturing technology with diverse clinical applications. In the field of oncology, the use of HIFU to non-invasively cause tissue necrosis in a defined target, a technique known as focused ultrasound surgery (FUS), has considerable potential for tumour ablation. In this article, we outline the development and underlying principles of HIFU, overview the limitations and commercially available equipment for FUS, then summarise some of the recent technological advances and experimental clinical trials that we predict will have a positive impact on extending the role of FUS in cancer therapy. PMID:23403455

  9. Development of a finite element human head model partially validated with thirty five experimental cases.

    PubMed

    Mao, Haojie; Zhang, Liying; Jiang, Binhui; Genthikatti, Vinay V; Jin, Xin; Zhu, Feng; Makwana, Rahul; Gill, Amandeep; Jandir, Gurdeep; Singh, Amrinder; Yang, King H

    2013-11-01

    This study is aimed to develop a high quality, extensively validated finite element (FE) human head model for enhanced head injury prediction and prevention. The geometry of the model was based on computed tomography (CT) and magnetic resonance imaging scans of an adult male who has the average height and weight of an American. A feature-based multiblock technique was adopted to develop hexahedral brain meshes including the cerebrum, cerebellum, brainstem, corpus callosum, ventricles, and thalamus. Conventional meshing methods were used to create the bridging veins, cerebrospinal fluid, skull, facial bones, flesh, skin, and membranes-including falx, tentorium, pia, arachnoid, and dura. The head model has 270,552 elements in total. Thirty five loading cases were selected from a range of experimental head impacts to check the robustness of the model predictions based on responses including the brain pressure, relative skull-brain motion, skull response, and facial response. The brain pressure was validated against intracranial pressure data reported by Nahum et al. (1977, "Intracranial Pressure Dynamics During Head Impact," Proc. 21st Stapp Car Crash Conference, SAE Technical Paper No. 770922) and Trosseille et al. (1992, "Development of a F.E.M. of the Human Head According to a Specific Test Protocol," Proc. 36th Stapp Car Crash Conference, SAE Technical Paper No. 922527). The brain motion was validated against brain displacements under sagittal, coronal, and horizontal blunt impacts performed by Hardy et al. (2001, "Investigation of Head Injury Mechanisms Using Neutral Density Technology and High-Speed Biplanar X-Ray," Stapp Car Crash Journal, 45, pp. 337-368; and 2007, "A Study of the Response of the Human Cadaver Head to Impact," Stapp Car Crash Journal, 51, pp. 17-80). The facial bone responses were validated under nasal impact (Nyquist et al. 1986, "Facial Impact Tolerance and Response," Proc. 30th Stapp Car Crash Conference, SAE Technical Paper No. 861896

  10. Nitric oxide and asymmetric dimethyl arginine (ADMA) levels in an experimental hydronephrotic kidney caused by unilateral partial ureteral obstruction

    PubMed Central

    Alan, Cabir; Kurt, Hasan Anil; Topaloğlu, Naci; Ersay, Ahmet Reşit; Çakir, Dilek Ülker; Baştürk, Gökhan

    2016-01-01

    ABSTRACT Aim Our aim is to measure asymmetric dimethyl arginine and nitric oxide levels in rats with induced unilateral acute ureteral obstruction to research the effects on the kidney. Material and Methods The study included 21 adolescent (average age 6 weeks) Sprague-Dawley male rats weighing between 240-290g divided at random into 3 groups. Group-1: Control group (n=6): underwent no procedures. Group-2: Sham group (n=6): underwent the same procedures as the experimental group without ureter and psoas muscle dissection. Group-3: Group with induced partial unilateral ureteral obstruction (n=9). All rats were sacrificed after 12 weeks. Superoxide dismutase enzyme activity and nitrite and nitrate salt levels were measured in renal tissue. Plasma nitrite-nitrate and ADMA levels were examined. Results In the experimental group histopathological changes observed included renal pelvis dilatation, flattened papillae, sclerotic glomerulus and fibrosis. In the experimental group tissue SOD and blood ADMA levels were higher than the control and sham groups (p<0.05) while tissue NO and plasma NO values were lower than in the sham and control groups (p<0.05). Conclusion Oxidative stress and disruption of NO synthesis play an important role in renal function and histopathological changes after obstructive renal disease. To prevent renal complications developing after obstructive nephropathy we believe that a new strategy may be research on reducing ADMA. PMID:27286129

  11. Formation of a hard tissue barrier after experimental pulp capping or partial pulpotomy in humans: an updated systematic review.

    PubMed

    Fransson, H; Wolf, E; Petersson, K

    2016-06-01

    The aim was to update a systematic review of pulp capping and partial pulpotomy by Olsson et al. (2006), by evaluating new evidence on formation of a hard tissue barrier after pulp capping and partial pulpotomy of experimental exposures in humans. PubMed (01-01-2005 to 01-03-2014) and CENTRAL were searched using specific keywords. Hand searches were made and the level of evidence for each included article was evaluated by the authors. The evidence of the conclusions was graded as strong, moderately strong, limited or insufficient. The initial search in PubMed yielded 215 abstracts. Hand searches of reference lists yielded no additional original scientific articles. After a selection process and interpretation, 22 articles were included and rated for level of evidence: no article was rated as high and seven as moderate. Overall the methodological quality of studies has improved since the previous systematic review was published in 2006. The conclusions are that there is limited scientific evidence that application of calcium hydroxide or mineral trioxide aggregate to an exposed pulp frequently results in formation of a hard tissue barrier, whereas adhesives or enamel matrix derivatives do not. There is insufficient scientific evidence that mineral trioxide aggregate promotes hard tissue formation more frequently than calcium hydroxide. PMID:26059916

  12. A joint experimental and numerical study of mechanisms associated to instability of partial cavitation on two-dimensional hydrofoil

    NASA Astrophysics Data System (ADS)

    Leroux, Jean-Baptiste; Coutier-Delgosha, Olivier; Astolfi, Jacques André

    2005-05-01

    The present work was carried out in the scope of a numerical-experimental collaborative research program, whose main objective is to understand the mechanisms of instabilities in partial cavitating flow. Experiments were conducted in the configuration of a rectangular foil located in a cavitation tunnel. Partial cavitation was investigated by multipoint wall-pressure measurements together with lift and drag measurements and numerical videos. The computations were conducted on two-dimensional hydrofoil section and are based on a single fluid model of cavitation: the liquid/vapor mixture is considered as a homogeneous fluid whose composition is regulated by a barotropic state law. The algorithm of resolution is derived from the SIMPLE approach, modified to take into account the high compressibility of the medium. Several physical features were pointed out by this joint approach. Particularly two distinct cavity self-oscillation dynamics characterized by two different frequencies (dynamics 1 and dynamics 2) were obtained experimentally and numerically at the angles of incidence of 6° and 8°. In both cases, the reentrant jet was found to be mainly responsible for the cavity breakdown. Dynamics 2 corresponds to the "classical" cavity breakdown and resulting cloud cavitation. A more complex flow pattern was evidenced for dynamics 1. In this case the growth/breakdown cycle of the cavity was observed at a lower Strouhal number (˜0.07/0.09) than dynamics 2 (˜0.3). Moreover, the mechanism is composed of two successive steps: (i) an interaction between the reentrant jet and the cavity interface in the closure region leading to the periodic shedding of secondary cavitation clouds before the main cloud detachment occurs, and (ii) a shock wave induced by the collapse of the main cloud, which influences the growth of the residual cavity.

  13. A petrologic, thermodynamic and experimental study of brachinites: Partial melt residues of an R chondrite-like precursor

    NASA Astrophysics Data System (ADS)

    Gardner-Vandy, Kathryn G.; Lauretta, Dante S.; McCoy, Timothy J.

    2013-12-01

    The primitive achondrites provide a window into the initial melting of asteroids in the early solar system. The brachinites are olivine-dominated meteorites with a recrystallized texture that we and others interpret as evidence of partial melting and melt removal on the brachinite parent body. We present a petrologic, thermodynamic and experimental study of the brachinites to evaluate the conditions under which they formed and test our hypothesis that the precursor material to the brachinites was FeO-rich compared to the precursors of other primitive achondrites. Petrologic analysis of six brachinites (Brachina, Allan Hills (ALH) 84025, Hughes 026, Elephant Moraine (EET) 99402, Northwest Africa (NWA) 3151, and NWA 4969) and one brachinite-like achondrite (NWA 5400) shows that they are meteorites with recrystallized texture that are enriched in olivine (⩾80 vol.%) and depleted in other minerals with respect to a chondritic mineralogy. Silicates in the brachinites are FeO-rich (Fa32-36). Brachinite-like achondrite Northwest Africa 5400 is similar in mineralogy and texture to the brachinites but with a slightly lower FeO-content (Fa30). Thermodynamic calculations yield equilibration temperatures above the Fe,Ni-FeS cotectic temperature (∼950 °C) for all meteorites studied here and temperatures above the silicate eutectic (∼1050 °C) for all but two. Brachina formed at an fO2 of ∼IW, and the other brachinites and NWA 5400 formed at ∼IW - 1. All the meteorites show great evidence of formation by partial melting having approximately chondritic to depleted chondritic mineralogies, equilibrated mineral compositions, and recrystallized textures, and having reached temperatures above that required for melt generation. In an attempt to simulate the formation of the brachinite meteorites, we performed one-atmosphere, gas-mixing partial melting experiments of R4 chondrite LaPaz Ice Field 03639. Experiments at 1250 °C and an oxygen fugacity of IW - 1 produce residual

  14. [Plastic surgery of the anterior cruciate ligament: experimental study of intra-articular aramid fibers in dogs].

    PubMed

    Passuti, N; Daculsi, G; Gouin, F; Martin, S; Vigneron, M

    1989-01-01

    The authors explored the possibility of replacing an anterior cruciate ligament with an aramid fiber (Kevlar) implant. This study was performed in intra-articular site in 9 dogs and the average implantation period was 5 months. Studies were carried out by macroscopic, photon microscopy, and electron microscopy examination of the samples obtained at the time the animals were sacrificed. Clinical and radiographic studies of the knees were performed in order to assess functional consequences. Overall, the results showed a partial or complete rupture of 10 neoligaments out of the 17 studied ligaments; on the other hand, osseous anchorage and reintegration in the intra-articular zone appeared satisfactory. Kevlar fiber only partially meets the performance specifications for an artificial ligament intended to serve as an anterior cruciate ligament substitute. Some positive results have encouraged the authors to carry on further this experimental study. PMID:2595049

  15. [Scaphoid percutaneous osteosynthesis by screw using computer assisted surgery: an experimental study].

    PubMed

    Liverneaux, P

    2005-01-01

    Scaphoid fractures are sometimes difficult to diagnose and even more difficult to fix. Recent progress such as miniaturization of osteosynthesis material, adoption of the percutaneous route, and widening of the indications to include undisplaced fractures has still not abolished complications. In this context, computer assisted surgery (CAS) may be useful and deserves further study. To apply it to the scaphoid, it is initially necessary to immobilize the "wrist hand fingers" unit in a device adapted to make it a rigid unit. It is then necessary to choose the correct configuration of CAS system. The pedicular fluoroscopic navigation system, which is apparently similar to scaphoid screw insertion, was chosen for this study. The goal of this study is to define the osteosynthesis bases of the scaphoid with CAS. A fresh anatomical subject divided at the elbow joint was prepared at the DETERCA laboratory of the university Bordeaux 2. The solid "wrist hand fingers" unit was immobilized in extension and ulnar deviation of the wrist by a malleable, stable and radio transparent device. The first stage consisted of a calibration of the surgical instruments and the "wrist hand fingers" unit, with a three-dimensional optical localization system. The guide wire was simulated by a gauged stylet. When the axis and the length of the screw had been determined virtually, insertion of the guide wire was carried out under guidance of the virtual images of the computer's screen, without the assistance of the fluoroscopy. Finally the canulated screw was inserted over the guide wire. Insertion was stopped when the screw reached the intra osseous virtually predetermined length. A check using conventional fluoroscopy made it possible to ensure the correct positioning of the screw. Our results show that it is possible to insert a screw into a scaphoid without conventional fluoroscopy, by using the fluoroscopic navigation system. The procedure was performed without difficulty, apart from the

  16. Fetal reconstructive surgery: experimental use of the latissimus dorsi flap to correct myelomeningocele in utero.

    PubMed

    Meuli-Simmen, C; Meuli, M; Hutchins, G M; Harrison, M R; Buncke, H J; Sullivan, K M; Adzick, N S

    1995-10-01

    A recent study in human fetuses with myelomeningocele produced evidence that nonclosure of the spine leads to progressive damage of the exposed spinal cord during pregnancy. Thus in utero coverage might spare function. We tested the use of the latissimus dorsi flap for fetal myelomeningocele repair. In seven sheep fetuses, a lumbar myelomeningocele type of lesion was created at 75 days' gestation and was covered with a "reversed" latissimus dorsi flap at 100 days. At term, the three survivors had healed cutaneous wounds and normal hindlimb function. The vascular pedicle of the latissimus dorsi flap was patent, the viable flap covered the entire lesion, and the underlying spinal cord was grossly intact. We conclude that the latissimus dorsi flap repair is suitable for fetal surgery and provides efficient coverage of the lesion. These results have clinical implications, since fetal myelomeningocele repair may be a compelling way to reduce the severe neurologic deficit in humans. PMID:7568473

  17. Topical acidification promotes healing of experimental deep partial thickness skin burns: a randomized double-blind preliminary study.

    PubMed

    Kaufman, T; Eichenlaub, E H; Angel, M F; Levin, M; Futrell, J W

    1985-12-01

    The effects of three buffered solutions with pH values of 3.5, 7.42 and 8.5, respectively, on the healing rate of deep partial skin thickness burns, was followed for 21 days in 16 guinea-pigs. Two symmetrical burns were inflicted on the back of each animal and then each individual wound was dressed with an irrigation disc dressing; solutions were coded (no. 1 to no. 3) and the animals were randomly divided and blindly treated as follows: Group A, solution no. 1 v. solution no. 2 (n = 4); Group B, solution no. 2 v. solution no. 3(n = 4); Group C, solution no. 1 v. solution no. 3(n = 4); Group D, non-irrigated disc dressings (n = 4). The solutions were applied to the surface of the burn wounds at a rate of 0.15 ml/cm2. Dressings were changed every 7 days to assess contraction and epithelialization by a sonic digitizer. On post-burn day 21 the newly formed scar tissue was measured in all wounds. After computation of the healing rate at the end of the study, the data were then related to the coded treating agent. Contraction did not differ in all test groups during the study. Epithelialization was significantly faster in the pH 3.5-treated burns than in the other treated wounds (P less than 0.001). The present study indicates that topical acidification of experimental deep partial skin thickness burns promoted healing. The precise mechanism should be elucidated. PMID:4092157

  18. Partial knee replacement

    MedlinePlus

    Most people recover quickly and have much less pain than they did before surgery. People who have a partial knee replacement recover faster than those who have a total knee replacement. Many people are able to walk ...

  19. Experimental studies on the usage possibilities of the Nd:YAG laser in the cataract surgery

    NASA Astrophysics Data System (ADS)

    Yu, Xiaomin; Ma, Nina; Li, Jiaze

    2005-01-01

    The investigations of used pulsed Q-switched neodymium:YAG laser induced plasma and shock wave during experimental lenses emulsification were presented. The formation and propagation of plasma and shock wave created by the high powered Nd:YAG laser pulses with a titanium target were imaged through optical multiple analysis, and the pressure of shock wave was calculated. The results of shock wave interacting with the lenses material were observed. The lenses, simulated at different hardness, were placed in containers filled with Ringer's solution. The experimental results are promising and show that the Nd:YAG laser can be used for human lens emulsification.

  20. An experimental study about haptic feedback in robotic surgery: may visual feedback substitute tactile feedback?

    PubMed

    Meccariello, Giuseppe; Faedi, Federico; AlGhamdi, Saleh; Montevecchi, Filippo; Firinu, Elisabetta; Zanotti, Claudia; Cavaliere, Davide; Gunelli, Roberta; Taurchini, Marco; Amadori, Andrea; Vicini, Claudio

    2016-03-01

    The aim of this study is to demonstrate the hypothesis that the experience of the surgeon is sufficient to partially compensate for the lack of haptic feedback of the robotic system da Vinci Si HD (Intuitive (®) ). Twenty-five international surgeons belonging to different areas of surgical specialization were divided into two groups of investigation: experts and non-experts in the use of da Vinci Platform. This allocation was made on the basis of the following criteria: the number of performed procedures, the number of robotic working days and the number of true console hours. All participants underwent a specific test to assess their ability to recognize the thickness of custom-made membranes, without the availability of haptic feedback. After the performance of the surgeons, score was given according to an appropriate evaluation system (time, preciseness, force of tension and finding a metallic object). The analysis of the performances of participants provided the following results: an average score of 8.87 for the experts compared to 3.57 of non-experts with significant difference (P < 0.05). Other parameters of interest as the average time to conduct the test showed a result of 28.8 s for experts and 71.3 s of non-experts. After our results, a significant difference between the two groups in terms of performance was found. Our hypothesis that the expertise ability of the experts might partially overcome the lack of haptic feedback was confirmed. Probably visual feedback may play a role. PMID:26559538

  1. KIDNEY STONE INCIDENCE AND METABOLIC URINARY CHANGES AFTER MODERN BARIATRIC SURGERY: REVIEW OF CLINICAL STUDIES, EXPERIMENTAL MODELS, AND PREVENTION STRATEGIES

    PubMed Central

    Canales, Benjamin K.; Hatch, Marguerite

    2014-01-01

    Bariatric surgery has been associated with increased metabolic kidney stone risk and post-operative stone formation. A MEDLINE search, performed for articles published between January 2005 and November 2013, identified 24 pertinent studies containing 683 bariatric patients with 24-hour urine profiles, 6,777 bariatric patients with kidney stone incidence, and 7,089 non-stone forming controls. Of all procedures reviewed, only Roux-en-Y gastric bypass (RYGB) was linked to post-operative kidney stone development, increasing stone incidence two-fold in non-stone formers (8.5%) and four-fold in patients with previous stone history (16.7%). High quality evidence from 7 studies (n=277 patients) before and after RYGB identified the following post-RYGB urinary lithogenic risk factors: 30% reduction in urine volume (the main driver of urinary crystal saturation), 40% reduction in urinary citrate (a potent stone inhibitor), and 50% increase in urinary oxalate (a stone promotor). Based on this, a summary of strategies to reduce calcium oxalate stone risk following RYGB is provided. Furthermore, recent experimental RYGB studies are assessed for insights into the pathophysiology of oxalate handling, and the literature in gut anion (oxalate) transport is reviewed. Finally, as a potential probiotic therapy for hyperoxaluria, primary data from our laboratory is presented, demonstrating a 70% reduction in urinary oxalate levels in four experimental RYGB animals after colonization with Oxalobacter formigines, a non-pathogenic gut commensal that uses oxalate as an energy source. Overall, urine profiles and kidney stone risk following bariatric surgery appear modifiable by dietary adjustments, appropriate supplementation, and lifestyle changes. For hyperoxaluria resistant to dietary oxalate restriction and calcium binding, well-designed human investigations are needed to identify additional means of lowering urinary oxalate, such as Oxalobacter colonization or empiric pyridoxine therapy

  2. Experimental assessment of energy requirements and tool tip visibility for photoacoustic-guided endonasal surgery

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Dagle, Alicia B.; Kazanzides, Peter; Boctor, Emad M.

    2016-03-01

    Endonasal transsphenoidal surgery is an effective approach for pituitary adenoma resection, yet it poses the serious risk of internal carotid artery injury. We propose to visualize these carotid arteries, which are hidden by bone, with an optical fiber attached to a surgical tool and a transcranial ultrasound probe placed on the patient's temple (i.e. intraoperative photoacoustic imaging). To investigate energy requirements for vessel visualization, experiments were conducted with a phantom containing ex vivo sheep brain, ex vivo bovine blood, and 0.5-2.5 mm thick human cadaveric skull specimens. Photoacoustic images were acquired with 1.2-9.3 mJ laser energy, and the resulting vessel contrast was measured at each energy level. The distal vessel boundary was difficult to distinguish at the chosen contrast threshold for visibility (4.5 dB), which was used to determine the minimum energies for vessel visualization. The blood vessel was successfully visualized in the presence of the 0-2.0 mm thick sphenoid and temporal bones with up to 19.2 dB contrast. The minimum energy required ranged from 1.2-5.0 mJ, 4.2-5.9 mJ, and 4.6-5.2 mJ for the 1.0 temporal and 0-1.5 mm sphenoid bones, 1.5 mm temporal and 0-0.5 mm sphenoid bones, and 2.0 mm temporal and 0-0.5 mm sphenoid bones, respectively, which corresponds to a fluence range of 4-21 mJ/cm2. These results hold promise for vessel visualization within safety limits. In a separate experiment, a mock tool tip was placed, providing satisfactory preliminary evidence that surgical tool tips can be visualized simultaneously with blood vessels.

  3. Experimental investigation of transport of discrete solids with surge flows in a 10.0 cm diameter partially filled pipe

    NASA Astrophysics Data System (ADS)

    Mahajan, B. M.

    1982-01-01

    The transport of discrete solids with surge flows in a partially filled slightly pitched horizontal pipe was investigated. The experimental apparatus, instrumentation, and procedures are described. The experiments were conducted using a cylindrical solid in a 10.0 cm (4 in) diameter pipe. The water surge flows were obtained by discharging different volumes of water into the pipe from a falling head open container which simulated a water closet. Flow induced solid velocities and stream depth histories at various locations along the length of the pipe were measured. The effects of water volume used, pipe slope, and size of the solid on the solid velocities were examined. Solid velocities were compared with the maximum water velocities estimated from the stream depth histories. Also, the distance traversed by the solids in the pipe were measured for those cases in which the solids did not clear the pipe. The solid velocity increased with an increase in water volume used, a decrease in the size of the solid, and an increase in the pipe slope. The solid velocity in the initial reach of the pipe was less than the maximum water velocity; and the solid velocity approaches the maximum water velocity as the solid traveled downstream, except for some experiments with small water volumes.

  4. Chloride-bearing liquids and partial melting of mantle eclogites: experimental study and application to the diamond-forming processes.

    NASA Astrophysics Data System (ADS)

    Safonov, Oleg

    2010-05-01

    Recent studies prove that the partial melting in some eclogite xenoliths in kimberlites is closely related to formation of diamonds in these rocks at 4-6 GPa and 1150-12500C [e.g. 1, 2]. Along with specific mineral assemblages, the products of the eclogite partial melting commonly include relics of potassium-rich silicic melts (45-65 wt. % of SiO2, 4-14 wt. % of K2O and K2O/Na2O > 1.0) [1, 2]. Available experimental data, however, demonstrate that such melts can not be produced by 'dry' or hydrous melting of a common eclogite. It implies that partial melting and conjugate diamond formation in mantle eclogites was triggered by infiltration of potassic fluids/melts. Assemblages of Cl-bearing phases and carbonates in eclogite xenoliths [1], and eclogitic diamonds [3-6] suggest that these agents were chloride-carbonate-H2O melts or/and chloride-H2O-CO2 fluids. In order to characterize interaction of both types of liquids with eclogites and their minerals, experiments in the eclogite-related systems with participation of CaCO3-Na2CO3-KCl-H2O or H2O-CO2-KCl are reviewed. Melting relations in the system eclogite-CaCO3-Na2CO3-KCl-H2O follow the general scheme proposed earlier for chloride-carbonate-silicate systems [7]. Below 12000C, Grt, Cpx and phlogopite (Phl) coexist with LCC only. Formation of Phl and Ca-rich Grt after Cpx indicate active reactions of Cpx with LCC accompanied by CO2 degassing and depletion of the clinopyroxene in jadeite. Subsequent dissolution of silicates in LCC at >1200OC results in formation of potassic silica-undersaturated carbonate and Cl-bearing melt (LCS) (37-40 wt. % of SiO2, 10-12 wt. % of K2O, ~3.5 wt. % of Cl) immiscible with the LCC. Compositional feature of this melt is very comparable to those of low-Mg carbonate-silicate melt inclusions in diamonds [6]. However, it is not relevant to the melt relics preserved in the partially molten eclogite xenoliths. Melting of eclogites with participation of the H2O-CO2-KCl fluid at 5 GPa at 1200

  5. Comparison of false-negative/positive results of intraoperative evoked potential monitoring between no and partial neuromuscular blockade in patients receiving propofol/remifentanil-based anesthesia during cerebral aneurysm clipping surgery: A retrospective analysis of 685 patients.

    PubMed

    Kim, Sung-Hoon; Jin, Seok-Joon; Karm, Myong-Hwan; Moon, Young-Jin; Jeong, Hye-Won; Kim, Jae-Won; Ha, Seung-Il; Kim, Joung-Uk

    2016-08-01

    Although the elicited responses of motor evoked potential (MEP) monitoring are very sensitive to suppression by anesthetic agents and muscle relaxants, the use of neuromuscular blockade (NMB) during MEP monitoring is still controversial because of serious safety concerns and diagnostic accuracy. Here, we evaluated the incidence of unacceptable movement and compared false-negative MEP results between no and partial NMB during cerebral aneurysm clipping surgery. We reviewed patient medical records for demographic data, anesthesia regimen, neurophysiology event logs, MEP results, and clinical outcomes. Patients were divided into 2 groups according to the intraoperative use of NMB: no NMB group (n = 276) and partial NMB group (n = 409). We compared the diagnostic accuracy of MEP results to predict postoperative outcomes between both groups. Additionally, we evaluated unwanted patient movement during MEP monitoring in both groups. Of the 685 patients, 622 (90.8%) manifested no intraoperative changes in MEP and no postoperative motor deficits. Twenty patients showed postoperative neurologic deficits despite preserved intraoperative MEP. False-positive MEP results were 3.6% in the no NMB group and 3.9% in the partial NMB group (P = 1.00). False-negative MEP results were 1.1% in the no NMB group and 4.2% in the partial NMB group (P = 0.02). No spontaneous movement or spontaneous respiration was observed in either group. Propofol/remifentanil-based anesthesia without NMB decreases the stimulation intensity of MEPs, which may reduce the false-negative ratio of MEP monitoring during cerebral aneurysm surgery. Our anesthetic protocol enabled reliable intraoperative MEP recording and patient immobilization during cerebral aneurysm clipping surgery. PMID:27559984

  6. Epilepsy (partial)

    PubMed Central

    2011-01-01

    Introduction About 3% of people will be diagnosed with epilepsy during their lifetime, but about 70% of people with epilepsy eventually go into remission. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of starting antiepileptic drug treatment following a single seizure? What are the effects of drug monotherapy in people with partial epilepsy? What are the effects of additional drug treatments in people with drug-resistant partial epilepsy? What is the risk of relapse in people in remission when withdrawing antiepileptic drugs? What are the effects of behavioural and psychological treatments for people with epilepsy? What are the effects of surgery in people with drug-resistant temporal lobe epilepsy? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 83 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiepileptic drugs after a single seizure; monotherapy for partial epilepsy using carbamazepine, gabapentin, lamotrigine, levetiracetam, phenobarbital, phenytoin, sodium valproate, or topiramate; addition of second-line drugs for drug-resistant partial epilepsy (allopurinol, eslicarbazepine, gabapentin, lacosamide, lamotrigine, levetiracetam, losigamone, oxcarbazepine, retigabine, tiagabine, topiramate, vigabatrin, or zonisamide); antiepileptic drug withdrawal for people with partial or

  7. Why arthroscopic partial meniscectomy?

    PubMed

    Lyu, Shaw-Ruey

    2015-09-01

    "Arthroscopic Partial Meniscectomy versus Sham Surgery for a Degenerative Meniscal Tear" published in the New England Journal of Medicine on December 26, 2013 draws the conclusion that arthroscopic partial medial meniscectomy provides no significant benefit over sham surgery in patients with a degenerative meniscal tear and no knee osteoarthritis. This result argues against the current practice of performing arthroscopic partial meniscectomy (APM) in patients with a degenerative meniscal tear. Since the number of APM performed has been increasing, the information provided by this study should lead to a change in clinical care of patients with a degenerative meniscus tear. PMID:26488013

  8. An experimental study on laser-induced suturing of venous grafts in cerebral revascularization surgery

    NASA Astrophysics Data System (ADS)

    Puca, Alfredo; Albanese, Alessio; Esposito, Giuseppe; Maira, Giulio; Rossi, Giacomo; Pini, Roberto

    2005-04-01

    To test laser-assisted high flow bypass in cerebral revascularization procedures, we set up an experimental model on rabbits which included harvesting a jugular vein graft and its implantation on the common carotid artery through a double end-to-side anastomosis. The study was carried out on 25 New Zealand rabbits by performing on each animal the proximal anastomosis using conventional suturing, while the distal one was obtained by means of low-power diode laser welding in association with the topical application of Indocyanine Green (ICG) solution to enhance local absorption of the laser light. After the procedure, the animals were subjected to a follow-up from 2 to 9 days. Bypass patency was evaluated by means of Doppler study. The vascular segments were excised and evaluated by histological and immunohistochemical examinations. Utilization of the diode laser was associated with a substantial shortening of the operative time, as well as with a more active endothelial regeneration process at the anastomotic site.

  9. [Use of intraosseous resorbable implants. Experimental evaluation and clinical applications in hand surgery].

    PubMed

    Voche, P; Merle, M

    1992-01-01

    The authors report about their experience with the use of absorbable intramedullary nails. After an experimental phase comprising mechanical tests and animal experiments in rabbits, the first clinical applications were for 24 cases of metacarpophalangeal arthrodesis of the thumb. For this indication, bone stabilization was achieved by associating an absorbable intramedullary nail and a metallic oblique pin. Evaluation in animals included, on one hand, a magnetic resonance imaging study, and on the other hand a histological study after the staggered sacrifice of the animals. This histological study was performed on non-decalcified bones by inclusion in methyl methacrylate resin. The mechanical results confirmed the appropriate resistance of these materials for use in the digital skeleton. The histological assessment showed that absorption begins around the 4th month by progressive fragmentation of the material and lasts over 3 years. The encouraging clinical experience and some obstacles encountered during its implementation hav led to two modifications: on one hand, a larger nail was used, on the other hand an absorbable oblique pin was developed, thus ensuring a fully absorbable osteosynthesis. PMID:1339719

  10. Experimental and theoretical study of the heating dynamics of carbon-containing optothermal fibre converters for laser surgery

    NASA Astrophysics Data System (ADS)

    Belikov, A. V.; Skrypnik, A. V.; Kurnyshev, V. Yu; Shatilova, K. V.

    2016-06-01

    We have studied carbon-containing optothermal fibre converters (COTFCs) that are located on the distal end of a quartz – quartz optical fibre for delivering laser radiation in medical laser surgery systems and differ in the thickness and structure of the layer of a material converting laser radiation into heat. The heating dynamics of 'thin-film' and '3D' converters have been investigated at average incident 980-nm semiconductor laser beam powers of 0.3, 1.0 and 4.0 W, with the converters placed freely in air. The results demonstrate that, before the instant of disintegration, the efficiency of laser heating of the converter surface can reach 3000 °C W-1 for thin-film converters, 1000 °C W-1 for spherical 3D converters and 55 °C W-1 for planar 3D converters. The thin-film converter breaks down at an average laser beam power as low as 0.30 +/- 0.05 W, which is accompanied by a considerable reduction in heating efficiency and is caused by the disintegration of the carbon film on its surface. The spherical 3D converter breaks down at an average power of 4.0 +/- 0.1 W, as a result of the disintegration of the carbon film on its surface and partial melting of a modified layer containing microbubbles. The carbon film on the surface of the planar 3D converter also disintegrates at an average power of 4.0 +/- 0.1 W, but the structure of the modified layer remains unchanged. We have constructed structural and optophysical models of the converters by simulating light absorption in carbon films on the surface of the COTFC and inside the microbubbles present in the modified layer of the converters. The proposed models of the COTFCs have been shown to adequately describe real converters.

  11. Experimental partial melting of the Allende (CV) and Murchison (CM) chondrites and the origin of asteroidal basalt

    NASA Astrophysics Data System (ADS)

    Jurewicz, A. J. G.; Mittlefehldt, D. W.; Jones, J. H.

    1993-05-01

    Following the investigation of Jurewicz et al. (1991) on the composition of partial melts of eucrites and angrites, this study investigates partial melts of the Allende and Murchison chondrites and details the anhydrous phase relations of both chondrites at 1 atm, under temperatures and oxygen fugacities plausigle for the formation of basaltic meteorites. It was found that, in general, ambient oxygen fugacity exerts a strong influence on the compositions of partial melts of chondrites by controlling the amount of FeO available to the silicate system. At high f(O2), angritic magmas are produced, whereas eucritic melts are produced at low levels of f(O2).

  12. Experimental partial melting of the Allende (CV) and Murchison (CM) chondrites and the origin of asteroidal basalt

    NASA Technical Reports Server (NTRS)

    Jurewicz, A. J. G.; Mittlefehldt, D. W.; Jones, J. H.

    1993-01-01

    Following the investigation of Jurewicz et al. (1991) on the composition of partial melts of eucrites and angrites, this study investigates partial melts of the Allende and Murchison chondrites and details the anhydrous phase relations of both chondrites at 1 atm, under temperatures and oxygen fugacities plausigle for the formation of basaltic meteorites. It was found that, in general, ambient oxygen fugacity exerts a strong influence on the compositions of partial melts of chondrites by controlling the amount of FeO available to the silicate system. At high f(O2), angritic magmas are produced, whereas eucritic melts are produced at low levels of f(O2).

  13. Spherical mechanism analysis of a surgical robot for minimally invasive surgery -- analytical and experimental approaches.

    PubMed

    Rosen, Jacob; Lum, Mitch; Trimble, Denny; Hannaford, Blake; Sinanan, Mika

    2005-01-01

    Recent advances in technology have led to the fusion of MIS techniques and robot devices. However, current systems are large and cumbersome. Optimizing the surgical robot mechanism will eventually lead to its integration into the operating room (OR) of the future becoming the extended presence of the surgeon and nurses in a room occupied by the patient alone. By optimizing a spherical mechanism using data collected in-vivo during MIS procedures, this study is focused on a bottom-up approach to developing a new class of surgical robotic arms while maximizing their performance and minimizing their size. The spherical mechanism is a rotational manipulator with all axes intersecting at the center of the sphere. Locating the rotation center of the mechanism at the MIS port makes this class of mechanism a suitable candidate for the first two links of a surgical robot for MIS. The required dexterous workspace (DWS) is defined as the region in which 95% of the tool motions are contained based on in-vivo measurements. The extended dexterous workspace (EDWS) is defined as the entire abdominal cavity reachable by a MIS instruments. The DWS is defined by a right circular cone with a vertex angle of 60 degrees and the EDWS is defined by a cone with an elliptical cross section created by two orthogonal vertex angles of 60 degrees and 90 degrees. A compound function based on the mechanism's isotropy and the mechanism stiffness was considered as the performance metric cost function. Optimization across both the DWS and the EDWS lead to a serial mechanism configuration with link length angles of 74 degrees and 60 degrees for a serial configuration. This mechanism configuration maximized the kinematic performance in the DWS while keeping the EDWS as its reachable workspace. Surgeons, using a mockup of two mechanisms in a MIS setup, validated these results experimentally. From these experiments the serial configuration was deemed most applicable for MIS robotic applications compared

  14. Robotic surgery

    MedlinePlus

    Robot-assisted surgery; Robotic-assisted laparoscopic surgery; Laparoscopic surgery with robotic assistance ... Robotic surgery is similar to laparoscopic surgery. It can be performed through smaller cuts than open surgery. ...

  15. Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust

    USGS Publications Warehouse

    Ratajeski, K.; Sisson, T.W.; Glazner, A.F.

    2005-01-01

    Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850??C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635-661, 2005) have major-element and modeled trace-element (REE, Rb, Ba, Sr, Th, U) compositions matching those of the Cretaceous El Capitan Granite, a prominent granite and silicic granodiorite pluton in the central part of the Sierra Nevada batholith (Yosemite, CA, USA) locally mingled with coeval, isotopically similar quartz diorite through gabbro intrusions (Ratajeski et al. in Geol Soc Am Bull 113:1486-1502, 2001). These results are evidence that the El Capitan Granite, and perhaps similar intrusions in the Sierra Nevada batholith with lithospheric-mantle-like isotopic values, were extracted from LILE-enriched, hydrous (hornblende-bearing) gabbroic rocks in the Sierran lower crust. Granitic partial melts derived by this process may also be silicic end members for mixing events leading to large-volume intermediate composition Sierran plutons such as the Cretaceous Lamarck Granodiorite. Voluminous gabbroic residues of partial melting may be lost to the mantle by their conversion to garnet-pyroxene assemblages during batholithic magmatic crustal thickening. ?? Springer-Verlag 2005.

  16. Biological and mechanical properties of an experimental glass-ionomer cement modified by partial replacement of CaO with MgO or ZnO.

    PubMed

    Kim, Dong-Ae; Abo-Mosallam, Hany; Lee, Hye-Young; Lee, Jung-Hwan; Kim, Hae-Won; Lee, Hae-Hyoung

    2015-01-01

    Some weaknesses of conventional glass ionomer cement (GIC) as dental materials, for instance the lack of bioactive potential and poor mechanical properties, remain unsolved.Objective The purpose of this study was to investigate the effects of the partial replacement of CaO with MgO or ZnO on the mechanical and biological properties of the experimental glass ionomer cements.Material and Methods Calcium fluoro-alumino-silicate glass was prepared for an experimental glass ionomer cement by melt quenching technique. The glass composition was modified by partial replacement (10 mol%) of CaO with MgO or ZnO. Net setting time, compressive and flexural properties, and in vitrorat dental pulp stem cells (rDPSCs) viability were examined for the prepared GICs and compared to a commercial GIC.Results The experimental GICs set more slowly than the commercial product, but their extended setting times are still within the maximum limit (8 min) specified in ISO 9917-1. Compressive strength of the experimental GIC was not increased by the partial substitution of CaO with either MgO or ZnO, but was comparable to the commercial control. For flexural properties, although there was no significance between the base and the modified glass, all prepared GICs marked a statistically higher flexural strength (p<0.05) and comparable modulus to control. The modified cements showed increased cell viability for rDPSCs.Conclusions The experimental GICs modified with MgO or ZnO can be considered bioactive dental materials. PMID:26398508

  17. Biological and mechanical properties of an experimental glass-ionomer cement modified by partial replacement of CaO with MgO or ZnO

    PubMed Central

    Dong-Ae, KIM; Hany, ABO-MOSALLAM; Hye-Young, LEE; Jung-Hwan, LEE; Hae-Won, KIM; Hae-Hyoung, LEE

    2015-01-01

    Some weaknesses of conventional glass ionomer cement (GIC) as dental materials, for instance the lack of bioactive potential and poor mechanical properties, remain unsolved. Objective The purpose of this study was to investigate the effects of the partial replacement of CaO with MgO or ZnO on the mechanical and biological properties of the experimental glass ionomer cements. Material and Methods Calcium fluoro-alumino-silicate glass was prepared for an experimental glass ionomer cement by melt quenching technique. The glass composition was modified by partial replacement (10 mol%) of CaO with MgO or ZnO. Net setting time, compressive and flexural properties, and in vitro rat dental pulp stem cells (rDPSCs) viability were examined for the prepared GICs and compared to a commercial GIC. Results The experimental GICs set more slowly than the commercial product, but their extended setting times are still within the maximum limit (8 min) specified in ISO 9917-1. Compressive strength of the experimental GIC was not increased by the partial substitution of CaO with either MgO or ZnO, but was comparable to the commercial control. For flexural properties, although there was no significance between the base and the modified glass, all prepared GICs marked a statistically higher flexural strength (p<0.05) and comparable modulus to control. The modified cements showed increased cell viability for rDPSCs. Conclusions The experimental GICs modified with MgO or ZnO can be considered bioactive dental materials. PMID:26398508

  18. Cosmetic Surgery

    MedlinePlus

    ... Body Looking and feeling your best Cosmetic surgery Cosmetic surgery Teens might have cosmetic surgery for a ... about my body? What are the risks of cosmetic surgery? top People who have cosmetic surgery face ...

  19. The Epicardial Neural Ganglionated Plexus of the Ovine Heart: Anatomical Basis for Experimental Cardiac Electrophysiology and Nerve Protective Cardiac Surgery

    PubMed Central

    Saburkina, Inga; Rysevaite, Kristina; Pauziene, Neringa; Mischke, Karl; Schauerte, Patrick; Jalife, José; Pauza, Dainius H.

    2011-01-01

    Summary BACKGROUND The sheep is routinely used in experimental cardiac electrophysiology and surgery. OBJECTIVE We aimed at (1) ascertaining the topography and architecture of the ovine epicardial neural plexus (ENP), (2) determining the relationships of the ENP with the vagal and sympathetic cardiac nerves and ganglia, and (3) evaluating gross anatomical differences and similarities among ENPs in humans, sheep and other species. METHODS The ovine ENP, extrinsic sympathetic and vagal nerves were revealed histochemically for acetylcholinesterase on whole heart and/or thorax-dissected preparations from 23 newborn lambs with subsequent examination by a stereomicroscope. RESULTS The intrinsic cardiac nerves extend from the venous part of the ovine heart hilum (HH) along the roots of the cranial (superior) caval and left azygos veins to both atria and ventricles via five epicardial routes; i.e. the dorsal right atrial (DRA), middle (MD), left dorsal (LD), right ventral (VR) and ventral left atrial (VLA) nerve subplexuses. Intrinsic nerves proceeding from the arterial part of the HH along the roots of the aorta and pulmonary trunk extend exclusively into the ventricles as the right and left coronary subplexuses. The DRA, RV, and MD subplexuses receive the main extrinsic neural input from the right cervicothoracic and the right thoracic sympathetic T2, T3 ganglia, as well as from the right vagal nerve. The LD is supplied by sizeable extrinsic nerves from the left thoracic T4-T6 sympathetic ganglia and the left vagal nerve. Sheep hearts contained on average 769±52 epicardial ganglia. Cumulative areas of epicardial ganglia on the root of the cranial vena cava and on the wall of the coronary sinus were the largest of all regions (p<0.05). CONCLUSION Despite substantial interindividual variability in the morphology of the ovine ENP, the right-sided epicardial neural subplexuses supplying the sinuatrial and atrioventricular nodes are mostly concentrated at a fat pad between

  20. Noncontrast and contrast enhanced MR imaging in the evaluation of partial ureteral obstruction: An experimental study in the micropig

    SciTech Connect

    Thurnher, S.; Tzika, A.A.; Hricak, H.; Mattei, P.; Aboseif, S.; Engelstad, B.; Price, D.C. )

    1989-07-01

    Twelve Yucatan micropigs (3 controls; 3 sham-operated; 6 with unilateral obstruction) were studied to assess the value of noncontrast and contrast-enhanced (Gadolinium-DTPA) magnetic resonance (MR) imaging in the evaluation of partial ureteral obstruction. MR findings were correlated with findings of quantitative (Tc-99m-DMSA) scintigraphy, and histology. On noncontrast T1-weighted images, the normal porcine kidney demonstrated good corticomedullary contrast (CMC = 16.8% +/- 5.0). Five minutes after administration of Gd-DTPA, there was enhancement of the renal cortex (+24.4%) and medulla (+46.2%), and CMC was no longer discernible. Enhancement of the urine within the collecting system (+119.1%) was also observed. The obstructed kidneys demonstrated marked thinning of the renal parenchyma and decreased signal intensity on noncontrast T1- and T2-weighted images (P less than 0.01). Urine in the dilated collecting system did not differ significantly from urine in controls except in the three animals with urinary tract infection (P less than 0.05). Five minutes following injection of Gd-DTPA, there was enhancement of the renal parenchyma in all kidneys. Excretion was seen in three pigs and no excretion in two. Thus, useful information can be obtained in partial ureteral obstruction from both pre-contrast and Gd-DTPA-enhanced MR images of the kidney.

  1. Healing of a surgically created partial detachment of the posterior cruciate ligament using marrow stimulation: an experimental study in dogs.

    PubMed

    Rodkey, William G; Arnoczky, Steven P; Steadman, J Richard

    2006-01-01

    The inability of intra-articular (cruciate) ligaments to generate a substantive reparative response may preclude the primary surgical repair of such lesions. A marrow stimulation technique that provides access to a fibrin scaffold, cytokines, and mesenchymal stem cells has been shown to be successful in generating a repair response in articular cartilage. We hypothesized that a similar approach may be effective in initiating and supporting a healing response in cruciate ligament injuries. The ability to treat cruciate ligament injuries by primary repair may have significant advantages over the more extensive reconstructive procedures currently advocated. Bilateral subtotal (75% of width) lacerations were made in the proximal aspect of the posterior cruciate ligament (PCL) in 10 adult mongrel dogs. A marrow stimulation technique in which small holes were made through the femoral origin of the PCL into the marrow cavity immediately adjacent to the lesion was performed in one limb. The contralateral limb served as the non-stimulated control. Twelve weeks after surgery the extent of healing and the histological character of the repair tissue in both groups were compared. Marrow stimulation resulted in a statistically significant (P<.05) improvement in the healing of subtotal lacerations made in the PCL. The marrow-stimulated repair tissue was more cellular and had a more organized extracellular matrix than the repair tissue in the non-stimulated group. Our hypothesis was confirmed. Marrow stimulation can induce a "healing response" in intra-articular (cruciate) ligaments. This technique may have clinical applications in primary surgical repair of these structures. PMID:16468489

  2. Experimental investigation of the electrical behavior of olivine during partial melting under pressure and application to the lunar mantle

    NASA Astrophysics Data System (ADS)

    Pommier, A.; Leinenweber, K.; Tasaka, M.

    2015-09-01

    Electrical conductivity measurements were performed during melting experiments of olivine compacts (dry and hydrous Fo77 and Fo90) at 4 and 6 GPa in order to investigate melt transport properties and quantify the effect of partial melting on electrical properties. Experiments were performed in the multi-anvil apparatus and electrical measurements were conducted using the impedance spectroscopy technique with the two-electrode method. Changes in impedance spectra were used to identify the transition from an electrical response controlled by the solid matrix to an electrical response controlled by the melt phase. This transition occurs slightly above the solidus temperature and lasts until Tsolidus + 75 °C (±25). At higher temperature, a significant increase in conductivity (corresponding to an increase in conductivity values by a factor ranging from ∼30 to 100) is observed, consistent with the transition from a tube-dominated network to a structure in which melt films and pools become prominent features. This increase in conductivity corresponds to an abrupt jump for all dry samples and to a smoother increase for the hydrous sample. It is followed by a plateau at higher temperature, suggesting that the electrical response of the investigated samples lacks sensitivity to temperature at an advanced stage of partial melting. Electron microprobe analyses on quenched products indicated an increase in Mg# (molar Mg / (Mg +Fe)) of olivine during experiments (∼77-93 in the quenched samples with an initial Fo77 composition and ∼92-97 in the quenched samples with an initial Fo90 composition) due to the partitioning of iron to the melt phase. Assuming a respective melt fraction of 0.10 and 0.20 before and after the phase of significant increase in conductivity, in agreement with previous electrical and permeability studies, our results can be reproduced satisfactorily by two-phase electrical models (the Hashin and Shtrikman bounds and the modified brick layer model

  3. A cost comparison analysis of partial versus whole-breast irradiation after breast-conserving surgery for early-stage breast cancer

    SciTech Connect

    Suh, W. . E-mail: wsuh@lroc.harvard.edu; Pierce, Lori J.; Vicini, Frank A.; Hayman, James A.

    2005-07-01

    Purpose: To assess, if and for whom, there are cost savings associated with alternate breast radiotherapy (RT) techniques when compared with the conventional external beam-based whole-breast RT with a boost (WBRT-B). Methods and Materials: Treatment planning and delivery utilization data were modeled for eight different breast RT techniques: (1) WBRT-B: 60 Gy in 30 fractions; (2) WBRT: 50 Gy in 25 fractions; (3) WBRT-accelerated (AC): 42.5 Gy in 16 fractions; (4) WBRT-intensity-modulated RT (IMRT): 60 Gy in 30 fractions; (5) accelerated partial breast irradiation (APBI)-IC, MammoSite: 34 Gy in 10 twice-daily fractions; (6) APBI-IT, HDR interstitial: 34 Gy in 10 twice-daily fractions; (7) APBI three-dimensional conformal RT (3D-CRT): 38.5 Gy in 10 twice-daily fractions; or (8) APBI-IMRT: 38.5 Gy in 10 twice-daily fractions. Costs incurred by payer (i.e., direct medical costs; 2003 Medicare Fee Schedule) and patient (i.e., direct nonmedical costs; time and travel) were estimated. Total societal costs were then calculated for each treatment approach. Results: Not all efforts to reduce overall treatment time result in total cost savings. The least expensive partial breast-based RT approaches were the external beam techniques (APBI-3D-CRT, APBI-IMRT). Any reduced cost to patients for the HDR brachytherapy-based APBI regimens were overshadowed by substantial increases in cost to payers, resulting in higher total societal costs; the cost of HDR treatment delivery was primarily responsible for the increased direct medical cost. For the whole breast-based RT approaches, treating without a boost (WBRT) or with WBRT-AC reduced total costs. Overall, WBRT-AC was the least costly of all the regimens, in terms of costs to society; APBI approaches, in general, were favored over whole-breast techniques when only considering costs to patients. Conclusions: Based on societal cost considerations, WBRT-AC appears to be the preferred approach. If one were to pursue a partial-breast RT

  4. Prostaglandin-targeting agents and spectral heart rate variability in experimental partial bladder outlet obstruction in rats.

    PubMed

    Dobrek, Ł; Baranowska, A; Skowron, B; Furgała, A; Żurowski, D; Thor, P

    2016-03-01

    The purpose of this study was to determine the activity of the autonomic nervous system (ANS), using spectral analysis of the heart rate variability (HRV) in the model of partial bladder outlet obstruction (PBOO) in rats treated with selected non-steroidal anti-inflammatory drugs (NSAID): piroxicam (PRX) or meloxicam (MLX), and following administration of PGF2a prostaglandin analogue (Enzaprost F5). Neither the use of PGF2a analogue nor of MLX, caused significant changes in the HRV spectrum (except for HRV spectrum total power reduction with MLX). The use of PRX caused reduction of the total power and powers of all components of the HRV spectrum (except for VLF). Moreover, increased nLF and reduced nHF were observed. The obtained results suggest that the total prostaglandin synthesis block with a non-selective cyclooxygenase inhibitor (PRX) results in reduced ANS total activity, with decreased parasympathetic activity and a relative sympathetic predominance. The preferential cyclooxygenase-2 block (MLX) caused reduction of the total ANS activity as well, however with no clear disproportion of any part of the ANS. Therefore, prostaglandin synthesis inhibition and associated decrease of parasympathetic activity may constitute an additional and favourable feature of NSAID pharmacodynamics in the treatment of BPH. PMID:27030625

  5. Accelerated Partial Breast Irradiation: 5-Year Results of the German-Austrian Multicenter Phase II Trial Using Interstitial Multicatheter Brachytherapy Alone After Breast-Conserving Surgery

    SciTech Connect

    Strnad, Vratislav; Hildebrandt, Guido; Poetter, Richard; Hammer, Josef; Hindemith, Marion; Resch, Alexandra; Spiegl, Kurt; Lotter, Michael; Uter, Wolfgang; Bani, Mayada; Kortmann, Rolf-Dieter; Beckmann, Matthias W.; Fietkau, Rainer; Ott, Oliver J.

    2011-05-01

    Purpose: To evaluate the impact of accelerated partial breast irradiation on local control, side effects, and cosmesis using multicatheter interstitial brachytherapy as the sole method for the adjuvant local treatment of patients with low-risk breast cancer. Methods and Materials: 274 patients with low-risk breast cancer were treated on protocol. Patients were eligible for the study if the tumor size was < 3 cm, resection margins were clear by at least 2 mm, no lymph node metastases existed, age was >35 years, hormone receptors were positive, and histologic grades were 1 or 2. Of the 274 patients, 175 (64%) received pulse-dose-rate brachytherapy (D{sub ref} = 50 Gy). and 99 (36%) received high-dose-rate brachytherapy (D{sub ref} = 32.0 Gy). Results: Median follow-up was 63 months (range, 9-103). Only 8 of 274 (2.9%) patients developed an ipsilateral in-breast tumor recurrence at the time of analysis. The 5-year actuarial local recurrence-free survival probability was 98%. The 5- year overall and disease-free survival probabilities of all patients were 97% and 96%, respectively. Contralateral in-breast malignancies were detected in 2 of 274 (0.7%) patients, and distant metastases occurred in 6 of 274 (2.2%). Late side effects {>=}Grade 3 (i.e., breast tissue fibrosis and telangiectasia) occurred in 1 patient (0.4%, 95%CI:0.0-2.0%) and 6 patients (2.2%, 95%CI:0.8-4.7%), respectively. Cosmetic results were good to excellent in 245 of 274 patients (90%). Conclusions: The long-term results of this prospective Phase II trial confirm that the efficacy of accelerated partial breast irradiation using multicatheter brachytherapy is comparable with that of whole breast irradiation and that late side effects are negligible.

  6. Size-dependent selectivity and activity of silver nanoclusters in the partial oxidation of propylene to propylene oxide and acrolein : A joint experimental and theoretical study.

    SciTech Connect

    Molina, L M.; Lee, S.; Sell, K.; Barcaro, G.; Fortunelli, A.; Lee, B.; Seifert, S.; Winans, R. E.; Elam, J. W.; Pellin, M. J.; Barke, I.; von Oeynhausen, V.; Lei, Y.; Meyer, R. J.; Alonso, J. A.; Fraile-Rodriguez, A.; Kleibert, A.; Giorgio, S.; Henry, C. R.; Heinz Meiwes-Broer, K.; Vadja, S.; Univ. de Valladolid; Univ. Rostock; IPCF-CNR; Univ. of Illinois at Chicago; Swiss Light Source; CINaM-CNRS and Aix-Marseille Univ.; Yale Univ.

    2011-02-02

    Model silver nanocatalysts between 9 and 23 nm in size were prepared by size-selected cluster deposition from a free cluster beam on amorphous alumina films and their size-dependent catalytic performance studied in the partial oxidation of propylene under realistic reaction conditions. Smaller clusters preferentially produced acrolein, while the 23 nm particles were considerably more selective towards the formation of propylene oxide, at reaction rates far exceeding those previously reported for larger silver particles. The activity of clusters dropped significantly with increasing particle size. First-principle calculations, of the activation energies for oxygen adsorption and its dissociation, at variable surface coverage yielded surface energies which resulted in particle shapes resembling the experimentally observed shapes of partially oxidized silver clusters. The calculated activation barriers for propylene oxide and acrolein formation on various facets and on the edges of the nanoparticles provided detailed information about the energetics of the competing reaction pathways. The size- and corresponding morphology dependent theoretical activity and selectivity are in good accord with experimental observations.

  7. Cataract Surgery

    MedlinePlus

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ...

  8. Cystometric parameters and the activity of signaling proteins in association with the compensation or decompensation of bladder function in an animal experimental model of partial bladder outlet obstruction.

    PubMed

    Choi, Bo-Hwa; Jin, Long-Hu; Kim, Khae-Hawn; Kang, Sung-An; Kang, Ju-Hee; Yoon, Sang-Min; Park, Chang-Shin; Lee, Tack

    2013-12-01

    We conducted this study to determine whether the degree of detrusor contractility is associated with the compensation or decompensation of bladder function depending on the residual volume (RV) during the first two weeks after the onset of partial bladder outlet obstruction (BOO). Moreover, we also examined whether the degree of the phosphorylation and expression of signaling proteins [AMP-activated kinase (AMPK), extracellular signal‑regulated protein kinases 1 and 2 (ERK1/2) and protein kinase C (PKC)] is associated with the prevalence of compensation or decompensation of bladder function. Twenty-seven female Sprague-Dawley (SD) rats were randomly assigned to either the sham-operated group (n=7) or the group with partial bladder outlet obstruction (BOO) (n=20). We then measured cystometric parameters from three reproducible micturition cycles and averaged the results for a comparison between the two groups. Based on a cut-off value of a mean RV% of 25%, we subdivided our experimental animals into two subgroups: the subgroup with bladder compensation (mean RV%, <25%) and the subgroup with bladder decompensation (mean RV%, >25%). Our results indicated that the degree of detrusor overactivity (DO) was associated with the compensation or decompensation of bladder function depending on the RV during the first two weeks after the onset of BOO in an animal experimental model of partial BOO. Moreover, we also demonstrate that AMPK and ERK1/2 are involved in the compensation or decompensation of bladder function. Furthermore, our results suggest that PKC is not involved in two-phase bladder contraction. Alterations in the activities of signaling proteins, such as AMPK and ERK1/2 may prove to be helpful in the treatment of patients with voiding difficulty. PMID:24085268

  9. Experimental study of vorticity-strain rate interaction in turbulent partially premixed jet flames using tomographic particle image velocimetry

    NASA Astrophysics Data System (ADS)

    Coriton, Bruno; Frank, Jonathan H.

    2016-02-01

    In turbulent flows, the interaction between vorticity, ω, and strain rate, s, is considered a primary mechanism for the transfer of energy from large to small scales through vortex stretching. The ω-s coupling in turbulent jet flames is investigated using tomographic particle image velocimetry (TPIV). TPIV provides a direct measurement of the three-dimensional velocity field from which ω and s are determined. The effects of combustion and mean shear on the ω-s interaction are investigated in turbulent partially premixed methane/air jet flames with high and low probabilities of localized extinction as well as in a non-reacting isothermal air jet with Reynolds number of approximately 13 000. Results show that combustion causes structures of high vorticity and strain rate to agglomerate in highly correlated, elongated layers that span the height of the probe volume. In the non-reacting jet, these structures have a more varied morphology, greater fragmentation, and are not as well correlated. The enhanced spatiotemporal correlation of vorticity and strain rate in the stable flame results in stronger ω-s interaction characterized by increased enstrophy and strain-rate production rates via vortex stretching and straining, respectively. The probability of preferential local alignment between ω and the eigenvector of the intermediate principal strain rate, s2, which is intrinsic to the ω-s coupling in turbulent flows, is larger in the flames and increases with the flame stability. The larger mean shear in the flame imposes a preferential orientation of ω and s2 tangential to the shear layer. The extensive and compressive principal strain rates, s1 and s3, respectively, are preferentially oriented at approximately 45° with respect to the jet axis. The production rates of strain and vorticity tend to be dominated by instances in which ω is parallel to the s1 ¯-s2 ¯ plane and orthogonal to s3 ¯.

  10. Experimental study of vorticity-strain rate interaction in turbulent partially-premixed jet flames using tomographic particle image velocimetry

    DOE PAGESBeta

    Coriton, Bruno; Frank, Jonathan H.

    2016-02-16

    In turbulent flows, the interaction between vorticity, ω, and strain rate, s, is considered a primary mechanism for the transfer of energy from large to small scales through vortex stretching. The ω-s coupling in turbulent jet flames is investigated using tomographic particle image velocimetry (TPIV). TPIV provides a direct measurement of the three-dimensional velocity field from which ω and s are determined. The effects of combustion and mean shear on the ω-s interaction are investigated in turbulent partially premixed methane/air jet flames with high and low probabilities of localized extinction as well as in a non-reacting isothermal air jet withmore » Reynolds number of approximately 13,000. Results show that combustion causes structures of high vorticity and strain rate to agglomerate in highly correlated, elongated layers that span the height of the probe volume. In the non-reacting jet, these structures have a more varied morphology, greater fragmentation, and are not as well correlated. The enhanced spatiotemporal correlation of vorticity and strain rate in the stable flame results in stronger ω-s interaction characterized by increased enstrophy and strain-rate production rates via vortex stretching and straining, respectively. The probability of preferential local alignment between ω and the eigenvector of the intermediate principal strain rate, s2, which is intrinsic to the ω-s coupling in turbulent flows, is larger in the flames and increases with the flame stability. The larger mean shear in the flame imposes a preferential orientation of ω and s2 tangential to the shear layer. The extensive and compressive principal strain rates, s1 and s3, respectively, are preferentially oriented at approximately 45° with respect to the jet axis. As a result, the production rates of strain and vorticity tend to be dominated by instances in which ω is parallel to the s1¯-s2¯ plane and orthogonal to s3¯.« less

  11. LES and experimental studies of cold and reacting flow in a swirled partially premixed burner with and without fuel modulation

    SciTech Connect

    Sengissen, A.X.; Van Kampen, J.F.; Huls, R.A.; Stoffels, G.G.M.; Kok, J.B.W.; Poinsot, T.J.

    2007-07-15

    In devices where air and fuel are injected separately, combustion processes are influenced by oscillations of the air flow rate but may also be sensitive to fluctuations of the fuel flow rate entering the chamber. This paper describes a joint experimental and numerical study of the mechanisms controlling the response of a swirled complex-geometry combustor burning natural gas and air. The flow is first characterized without combustion and LDV results are compared to large eddy simulation (LES) data. The nonpulsated reacting regime is then studied and characterized in terms of the heat release field. Finally the fuel flow rate is pulsated at several amplitudes and the response of the chamber is analyzed using phase-locked averaging and acoustic analysis. Results show that LES and acoustic analysis predict the flame dynamics in this complex configuration with accuracy when heat losses (radiation and convection) are accounted for. (author)

  12. Purple Pitcher Plant (Sarracenia rosea) Dieback and Partial Community Disassembly following Experimental Storm Surge in a Coastal Pitcher Plant Bog

    PubMed Central

    Abbott, Matthew J.; Battaglia, Loretta L.

    2015-01-01

    Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change. PMID:25874369

  13. Purple pitcher plant (Sarracenia rosea) Dieback and partial community disassembly following experimental storm surge in a coastal pitcher plant bog.

    PubMed

    Abbott, Matthew J; Battaglia, Loretta L

    2015-01-01

    Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change. PMID:25874369

  14. Finnish Degenerative Meniscal Lesion Study (FIDELITY): a protocol for a randomised, placebo surgery controlled trial on the efficacy of arthroscopic partial meniscectomy for patients with degenerative meniscus injury with a novel ‘RCT within-a-cohort’ study design

    PubMed Central

    Sihvonen, Raine; Paavola, Mika; Malmivaara, Antti; Järvinen, Teppo L N

    2013-01-01

    Introduction Arthroscopic partial meniscectomy (APM) to treat degenerative meniscus injury is the most common orthopaedic procedure. However, valid evidence of the efficacy of APM is lacking. Controlling for the placebo effect of any medical intervention is important, but seems particularly pertinent for the assessment of APM, as the symptoms commonly attributed to a degenerative meniscal injury (medial joint line symptoms and perceived disability) are subjective and display considerable fluctuation, and accordingly difficult to gauge objectively. Methods and analysis A multicentre, parallel randomised, placebo surgery controlled trial is being carried out to assess the efficacy of APM for patients from 35 to 65 years of age with a degenerative meniscus injury. Patients with degenerative medial meniscus tear and medial joint line symptoms, without clinical or radiographic osteoarthritis of the index knee, were enrolled and then randomly assigned (1 : 1) to either APM or diagnostic arthroscopy (placebo surgery). Patients are followed up for 12 months. According to the prior power calculation, 140 patients were randomised. The two randomised patient groups will be compared at 12 months with intention-to-treat analysis. To safeguard against bias, patients, healthcare providers, data collectors, data analysts, outcome adjudicators and the researchers interpreting the findings will be blind to the patients’ interventions (APM/placebo). Primary outcomes are Lysholm knee score (a generic knee instrument), knee pain (using a numerical rating scale), and WOMET score (a disease-specific, health-related quality of life index). The secondary outcome is 15D (a generic quality of life instrument). Further, in one of the five centres recruiting patients for the randomised controlled trial (RCT), all patients scheduled for knee arthroscopy due to a degenerative meniscus injury are prospectively followed up using the same protocol as in the RCT to provide an external

  15. Experimental study on heat transmission to the vestibule during CO2 laser use in revision stapes surgery.

    PubMed

    Szymański, M; Morshed, K; Mills, R

    2007-01-01

    We studied the transmission of heat to the vestibule during revision stapes surgery with a piston in situ, using a CO2 laser, in an in vitro model. A type K thermocouple was placed around the medial end of stainless steel and fluoroplastic wire pistons in a 'vestibule' filled with saline. The effect of laser hits on fluoroplastic wire and stainless steel stapes prostheses was investigated. The effect of introducing a vein graft to seal the stapedotomy was also examined. Greater temperature rises occurred with stainless steel than with fluoroplastic wire pistons. The addition of the vein graft reduced heat transmission. Application of the CO2 laser to fluoroplastic wire pistons, using the power settings suggested by the manufacturer, is not likely to damage the inner-ear structures. Application of 6 W laser energy to stainless steel pistons can potentially disturb the inner-ear function. PMID:17076928

  16. Foot Surgery

    MedlinePlus

    ... About Feet » Foot Health Information Surgery When is Foot Surgery Necessary? Many foot problems do not respond ... restore the function of your foot. Types of Foot Surgery Fusions: Fusions are usually performed to treat ...

  17. Outpatient Surgery

    MedlinePlus

    Policymakers | Members | Patients | News Media Anesthesia 101 Patient Safety Stories Resources About Home » Patients » Preparing For Surgery » Types of Surgery » Outpatient Surgery Share this Page Preparing For ...

  18. Plastic Surgery

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...

  19. Robotic surgery

    MedlinePlus

    Robot-assisted surgery; Robotic-assisted laparoscopic surgery; Laparoscopic surgery with robotic assistance ... computer station and directs the movements of a robot. Small surgical tools are attached to the robot's ...

  20. Lung surgery

    MedlinePlus

    ... Pneumonectomy; Lobectomy; Lung biopsy; Thoracoscopy; Video-assisted thoracoscopic surgery; VATS ... You will have general anesthesia before surgery. You will be asleep and unable to feel pain. Two common ways to do surgery on your lungs are thoracotomy and video- ...

  1. Physiologic Responses to Infrarenal Aortic Cross-Clamping during Laparoscopic or Conventional Vascular Surgery in Experimental Animal Model: Comparative Study

    PubMed Central

    Martín-Cancho, María F.; Crisóstomo, Verónica; Soria, Federico; Calles, Carmen; Sánchez-Margallo, Francisco M.; Díaz-Güemes, Idoia; Usón-Gargallo, Jesús

    2008-01-01

    The aim of this study was to compare the hemodynamic and ventilatory effects of prolonged infrarenal aortic cross-clamping in pigs undergoing either laparotomy or laparoscopy. 18 pigs were used for this study. Infrarenal aortic crossclamping was performed for 60 minutes in groups I (laparotomy, n = 6) and II (laparoscopy, n = 6). Group III (laparoscopy, n = 6) underwent a 120-minute long pneumoperitoneum in absence of aortic clamping (sham group). Ventilatory and hemodynamic parameters and renal function were serially determined in all groups. A significant decrease in pH and significant increase in PaCO2 were observed in group II, whereas no changes in these parameters were seen in group I and III. All variables returned to values similar to baseline in groups I and II 60 minutes after declamping. A significant increase in renal resistive index was evidenced during laparoscopy, with significantly higher values seen in Group II. Thus a synergic effect of pneumoperitoneum and aortic cross-clamping was seen in this study. These two factors together cause decreased renal perfusion and acidosis, thus negatively affecting the patient's general state during this type of surgery. PMID:21197458

  2. Does Laser Surgery Interfere with Optical Nerve Identification in Maxillofacial Hard and Soft Tissue?--An Experimental Ex Vivo Study.

    PubMed

    Bergauer, Bastian; Knipfer, Christian; Amann, Andreas; Rohde, Maximilian; Tangermann-Gerk, Katja; Adler, Werner; Schmidt, Michael; Nkenke, Emeka; Stelzle, Florian

    2015-01-01

    The protection of sensitive structures (e.g., nerves) from iatrogenic damage is of major importance when performing laser surgical procedures. Especially in the head and neck area both function and esthetics can be affected to a great extent. Despite its many benefits, the surgical utilization of a laser is therefore still limited to superficial tissue ablation. A remote feedback system which guides the laser in a tissue-specific way would provide a remedy. In this context, it has been shown that nerval structures can be specifically recognized by their optical diffuse reflectance spectra both before and after laser ablation. However, for a translation of these findings to the actual laser ablation process, a nerve protection within the laser pulse is of utmost significance. Thus, it was the aim of the study to evaluate, if the process of Er:YAG laser surgery--which comes with spray water cooling, angulation of the probe (60°) and optical process emissions--interferes with optical tissue differentiation. For the first time, no stable conditions but the ongoing process of laser tissue ablation was examined. Therefore, six different tissue types (nerve, skin, muscle, fat, cortical and cancellous bone) were acquired from 15 pig heads. Measurements were performed during Er:YAG laser ablation. Diffuse reflectance spectra (4500, wavelength range: 350-650 nm) where acquired. Principal component analysis (PCA) and quadratic discriminant analysis (QDA) were calculated for classification purposes. The clinical highly relevant differentiation between nerve and bone was performed correctly with an AUC of 95.3% (cortial bone) respectively 92.4% (cancellous bone). The identification of nerve tissue against the biological very similar fat tissue yielded good results with an AUC value of 83.4% (sensitivity: 72.3%, specificity: of 82.3%). This clearly demonstrates that nerve identification by diffuse reflectance spectroscopy works reliably in the ongoing process of laser ablation

  3. Long-Acting Local Anesthetics in Oral Surgery: An Experimental Evaluation of Bupivacaine and Etidocaine for Infiltration Anesthesia

    PubMed Central

    Danielsson, Karlhâkan; Evers, Hans; Nordenram, Åke

    1985-01-01

    The effect of bupivacaine 7.5 mg/ml with epinephrine 5μg/ml, etidocaine 15 mg/ml with epinephrine 5 μg/ml, and lidocaine 20 mg/ml with epinephrine 12.5 μg/ml was studied when used for oral infiltration anesthesia. Twenty healthy volunteers took part in the experimental and double-blind study. One ml of the respective anesthetic solution was deposited supraperiosteally in the apical area of the maxillary right lateral incisor. Onset time, frequency of analgesia, gingival spread, and duration of tooth analgesia were studied and duration of soft-tissue numbness registered. The present investigation showed that lidocaine had a shorter onset time compared with bupivacaine. No difference with regard to frequency was found. Bupivacaine and etidocaine had a longer period of soft-tissue numbness, but a significantly shorter duration of tooth analgesia than lidocaine. PMID:3859232

  4. Transauricular embolization of the rabbit coronary artery for experimental myocardial infarction: comparison of a minimally invasive closed-chest model with open-chest surgery

    PubMed Central

    2012-01-01

    Introduction To date, most animal studies of myocardial ischemia have used open-chest models with direct surgical coronary artery ligation. We aimed to develop a novel, percutaneous, minimally-invasive, closed-chest model of experimental myocardial infarction (EMI) in the New Zealand White rabbit and compare it with the standard open-chest surgical model in order to minimize local and systemic side-effects of major surgery. Methods New Zealand White rabbits were handled in conformity with the "Guide for the Care and Use of Laboratory Animals" and underwent EMI under intravenous anesthesia. Group A underwent EMI with an open-chest method involving surgical tracheostomy, a mini median sternotomy incision and left anterior descending (LAD) coronary artery ligation with a plain suture, whereas Group B underwent EMI with a closed-chest method involving fluoroscopy-guided percutaneous transauricular intra-arterial access, superselective LAD catheterization and distal coronary embolization with a micro-coil. Electrocardiography (ECG), cardiac enzymes and transcatheter left ventricular end-diastolic pressure (LVEDP) measurements were recorded. Surviving animals were euthanized after 4 weeks and the hearts were harvested for Hematoxylin-eosin and Masson-trichrome staining. Results In total, 38 subjects underwent EMI with a surgical (n = 17) or endovascular (n = 21) approach. ST-segment elevation (1.90 ± 0.71 mm) occurred sharply after surgical LAD ligation compared to progressive ST elevation (2.01 ± 0.84 mm;p = 0.68) within 15-20 min after LAD micro-coil embolization. Increase of troponin and other cardiac enzymes, abnormal ischemic Q waves and LVEDP changes were recorded in both groups without any significant differences (p > 0.05). Infarct area was similar in both models (0.86 ± 0.35 cm in the surgical group vs. 0.92 ± 0.54 cm in the percutaneous group;p = 0.68). Conclusion The proposed model of transauricular coronary coil embolization avoids thoracotomy and major

  5. THE INFLUENCE OF MONTELUKAST ON THE ACTIVITY OF THE AUTONOMIC NERVOUS SYSTEM ESTIMATED BY HEART RATE VARIABILITY IN EXPERIMENTAL PARTIAL BLADDER OUTLET OBSTRUCTION IN RATS.

    PubMed

    Dobrek, Łukasz; Skowron, Beata; Baranowska, Agnieszka; Zurowski, Daniel; Thor, Piotr Jan

    2016-01-01

    Due to their paracrine action, leukotrienes released from the urothelium are involved in control of the bladder function. Anti-leukotriene agents appear to exert an ameliorating effect in bladder overactivity. It is unknown, whether their possible, modulatory impact on the autonomic nervous system (ANS) activity may also contribute to the potentially beneficial effect of those compounds. Therefore, our aim was to indirectly estimate the ANS function using the heart rate variability (HRV) study in rats with experimental partial bladder outlet obstruction (PBOO), reflecting human benign prostatic hyperplasia (BPH), treated with leukotriene receptor antagonist - montelukast (MLKT). Twenty rats with surgically induced PBOO lasting for 14 days, divided into two groups: group 1 (10 control subjects) and group 2 (10 MLKT-treated rats; 2 mg/rat/day) were subjected to HRV recordings, preceded by daily urine collection and a subsequent cystectomy with histopathological evaluation of collected bladders. Standard HRV time and spectral parameters were calculated. MLKT-treated animals demonstrated an increase in power of non-normalized LF (low frequency) and HF (high frequency) components with no change of the total HRV power. Moreover, an increase and decrease in normalized nLF and nHF, respectively, were assessed in those animals compared to the control. Additionally, a decrease in daily diuresis measurement was demonstrated in MLKT-treated animals. Montelukast treatment resulted in the functional ANS status re-arrangement, with sympathetic overdrive and parasympathetic withdrawal. Those changes may contribute to alleviation of bladder overactivity symptoms, independently on leukotriene receptors blockade. PMID:27476297

  6. Kinetic-Hydrodynamic Models of the Solar Wind Interaction with the Partially Ionized Supersonic Flow of the Local Interstellar Gas: Predictions and Interpretations of the Experimental Data

    NASA Astrophysics Data System (ADS)

    Baranov, Vladimir B.

    2009-02-01

    At present there is no doubt that the local interstellar medium (LISM) is mainly partially ionized hydrogen gas moving with a supersonic flow relative to the solar system. The bulk velocity of this flow is approximately equal ˜26 km/s. Although the interaction of the solar wind with the charged component (below plasma component) of the LISM can be described in the framework of hydrodynamic approach, the interaction of H atoms with the plasma component can be correctly described only in the framework of kinetic theory because the mean free path of H atoms in the main process of the resonance charge exchange is comparable with a characteristic length of the problem considered. Results of self-consistent, kinetic-hydrodynamic models are considered in this review paper. First, such the model was constructed by Baranov and Malama (J. Geophys. Res. 98(A9):15,157-15,163, 1993). Up to now it is mainly developed by Moscow group taking into account new experimental data obtained onboard spacecraft studying outer regions of the solar system (Voyager 1 and 2, Pioneer 10 and 11, Hubble Space Telescope, Ulysses, SOHO and so on). Predictions and interpretations of experimental data obtained on the basis of these models are presented. Kinetic models for describing H atom motion were later suggested by Fahr et al. (Astron. Astrophys 298:587-600, 1995) and Lipatov et al. (J. Geophys. Res. 103(A9):20,631-20,642, 1998). However they were not self-consistent and did not incorporate sources to the plasma component. A self-consistent kinetic-hydrodynamic model suggested by Heerikhuisen et al. (J. Geophys. Res. 111:A06110, 2006, Astrophys. J. 655:L53-L56, 2007) was not tested on the results by Baranov and Malama (J. Geophys. Res. 111:A06110, 1993) although it was suggested much later. Besides authors did not describe in details their Monte Carlo method for a solution of the H atom Boltzmann equation and did not inform about an accuracy of this method. Therefore the results of

  7. Brain surgery

    MedlinePlus

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... Before surgery, the hair on part of the scalp is shaved and the area is cleaned. The doctor makes ...

  8. After Surgery

    MedlinePlus

    ... side effects. There is usually some pain with surgery. There may also be swelling and soreness around ... the first few days, weeks, or months after surgery. Some other questions to ask are How long ...

  9. Turbinate surgery

    MedlinePlus

    Turbinectomy; Turbinoplasty; Turbinate reduction; Nasal airway surgery ... There are several types of turbinate surgery: Turbinectomy: All or part of the lower turbinate is taken out. This can be done in several different ways, but sometimes a ...

  10. Fixation of Light Weight Polypropylene Mesh with n-Butyl-2-cyanocrylate in Pelvic Floor Surgery: Experimental Design Approach in Sheep for Effectiveness Evaluation

    PubMed Central

    Barbosa, Sandra; Nieves, Tania; García, Félix; Cepeda, Eva; Moll, Xavier; Marco, Alberto; Weis, Christine; Turon, Pau; Vergara, Patri

    2015-01-01

    Objective. The aim of this study was to find a proper experimental design and to evaluate n-butyl-2-cyanoacrylate (Histoacryl) as a fixation method for a light-weight and large pore PP mesh (Synthetic PP Mesh-1) using the sheep as an animal model. Methods. Posterior vaginal implantation by means of episiotomy was used to implant 8 ewes which were evaluated macroscopically and histologically at 3 months (n = 4) and 6 months (n = 4) post-surgery. In previous pilot studies anterior vaginal implantation was evaluated, as well as different synthetic mesh materials, sizes and fixation methods (n = 1 to 3) during three weeks. In all cases a clinical evaluation of the animal was performed. Results. A reduction in the mesh size (Synthetic PP Mesh-1) together with precise application of the surgical glue Histoacryl to fix the mesh yielded significantly better histocompatibility results (P < 0.01) compared to larger size or other fixation methods. Conclusion. The combination of Synthetic PP Mesh-1 with Histoacryl offered a high degree of graft integration without vaginal ulceration and a minimal foreign body reaction, being the sheep a proper animal model to test these types of medical devices. PMID:26221605

  11. Orthopedic surgery.

    PubMed

    Gehrig, Laura M B

    2011-09-01

    Orthopedic surgery is a specialty of surgery dedicated to the prevention, diagnosis, and treatment of diseases and injuries of the musculoskeletal system in all age groups. Careers in orthopedic surgery span the spectrum from general orthopedics to those of subspecialty expertise in orthopedic trauma, hand, pediatrics, total joint, foot and ankle, sports medicine, and oncology to name a few. PMID:21871990

  12. Surgery, drugs, lifestyle, and hyperlipidemia.

    PubMed

    Dalessandri, K M; Organ, C H

    1995-04-01

    Heart disease is the number-one cause of death in the United States, and more money is spent on its treatment each year than for any other condition. Both epidemiologic and experimental data clearly show that elevated plasma cholesterol levels increase the risk of death from coronary heart disease. Genetic insufficiencies can cause high blood cholesterol, but most people with high cholesterol do not have genetic abnormalities; rather, they have lifestyles that include high-fat diets and little exercise. Cholesterol can be managed aggressively with coronary artery bypass surgery, percutaneous transluminal coronary angioplasty, partial ileal bypass, and even liver transplant. Antihyperlipidemic drugs include bile-acid-binding resins, nicotinic acid, fibric acid derivatives, hydroxymethyglutaryl coenzyme A-reductase inhibitors, and the antioxidant probucol. Strict programs of low-fat diets and exercise are also effective for reducing cholesterol, lowering blood pressure, and preventing heart disease without the side effects associated with surgery and drug therapy. Such lifestyle changes are critical to reducing the incidence of heart disease in this country. PMID:7694974

  13. Flow of a reactive fluid through partially saturated fractures: Experimental observations of the influence of entrapped phase geometry on evolving flow channels

    NASA Astrophysics Data System (ADS)

    Detwiler, R. L.; Fisher, S.

    2008-12-01

    Reactive fluids cause dissolution and precipitation along mineral surfaces that can lead to the development of flow channels in porous and fractured media. In fully saturated fractures, dissolution of fracture surfaces leads to different behaviors depending on the relative magnitudes of advective and diffusive transport of dissolved minerals and surface reaction rates. The resulting alterations of the fracture pore space (apertures) range from relatively uniform dissolution of the fracture surfaces to the formation of distinct dissolution channels that dominate flow through the fracture. These processes are further complicated in many subsurface systems, where multiple fluids/phases interact within pore spaces (e.g., CO2 sequestration, groundwater contamination by organic solvents, oil and gas production). We present experimental results that explore the additional influence of an entrapped nonwetting phase on the formation of dissolution channels in fractures. We fabricated analog fractures by mating a 10x15-cm, smooth, reactive surface (KH2PO4) with a rough, non-reactive surface (glass). The resulting fractures were transparent allowing direct measurement of evolving fracture apertures and fluid phase distribution using established quantitative visualization techniques. Experiments were initiated by slowly injecting (negligible viscous forces) air into a fully saturated fracture followed by slow reinvasion of water. The resulting initial condition for the fracture dissolution experiments was a complex distribution of immobile air bubbles entrapped predominantly within large aperture regions. These bubbles were completely surrounded by flowing water (under-saturated with respect to KH2PO4) within smaller aperture regions. During experiments, mineral dissolution led to localized fracture aperture growth, which in turn caused gradual redistribution of the entrapped air within the fracture. The resulting evolution of dissolution channels differed significantly from

  14. Coupler for surgery on small animals

    NASA Technical Reports Server (NTRS)

    Johnson, J. E., Jr.; Swartz, P. F.

    1979-01-01

    Minicoupler simplifies exchange of fluids with organs of laboratory animals enabling one person to perform surgery on experimental animals such as rats and mice. Innovation eliminates obstructing hands and instruments from areas of surgery.

  15. Effect of Catechol-O-methyltransferase-gene (COMT) Variants on Experimental and Acute Postoperative Pain in 1,000 Women undergoing Surgery for Breast Cancer

    PubMed Central

    Kambur, Oleg; Kaunisto, Mari A.; Tikkanen, Emmi; Leal, Suzanne M.; Ripatti, Samuli; Kalso, Eija A.

    2016-01-01

    Background Catechol-O-methyltransferase (COMT) metabolizes catecholamines in different tissues. Polymorphisms in COMT gene can attenuate COMT activity and increase sensitivity to pain. Human studies exploring the effect of COMT polymorphisms on pain sensitivity have mostly included small, heterogeneous samples and have ignored several important single nucleotide polymorphisms (SNPs). This study examines the effect of COMT polymorphisms on experimental and postoperative pain phenotypes in a large ethnically homogeneous female patient cohort. Methods Intensity of cold (+2–4°C) and heat (+48°C) pain and tolerance to cold pain were assessed in 1,000 patients scheduled for breast cancer surgery. Acute postoperative pain and oxycodone requirements were recorded. Twenty-two COMT SNPs were genotyped and their association with six pain phenotypes analyzed with linear regression. Results There was no association between any of the tested pain phenotypes and SNP rs4680. The strongest association signals were seen between rs165774 and heat pain intensity as well as rs887200 and cold pain intensity. In both cases, minor allele carriers reported less pain. Neither of these results remained significant after strict multiple testing corrections. When analyzed further, the effect of rs887200 was, however, shown to be significant and consistent throughout the cold pressure test. No evidence of association between the SNPs and postoperative oxycodone consumption was found. Conclusions SNPs rs887200 and rs165774 located in the untranslated regions of the gene had the strongest effects on pain sensitivity. Their effect on pain is described here for the first time. These results should be confirmed in further studies and the potential functional mechanisms of the variants studied. PMID:24343288

  16. [The possibilities for the application of the fluoroplast-based prostheses with a diamond-like carbon nanocoating in ear surgery (an experimental study)].

    PubMed

    Sitnikov, V P; Shil'ko, S V; Khusam, Él'-Refaĭ; Nadyrov, É A; Kazachenko, V P; Dzhaĭnakbaev, N T

    2014-01-01

    The objective of the present study was to elucidate general and local characteristics of the tissue reactions to the implantation of radiation-modified polytetrafluoroethylene (PTFE)-based fluoroplast F-4PM20 with a diamond-like carbon (DLC) nanocoating or with the diamond-like carbon coating containing the dispersed nano-sized silver particles to the experimental animals (rats). A total of 150 inbred white rats were included into the experiment; they were divided into 3 groups comprised of 50 animals each. The rats in group 1 were implanted with the 5 nm thick strips of fluoroplast F-4PM20 having the diamond-like carbon nanocoating. The animals of group 2 were implanted with the same material containing nanoparticles of chemically pure silver dispersed in the coating, those in group 3 (controls) were implanted with the fluoroplast F-4PM20 without a coating. The animals were sacrificed on days 7, 21, 30, and 60 days after the onset of the experiment. The tissues surrounding the implant as well as heart, lung, spleen, liver, and kidney tissues were taken for the histological study. The local reactions of different tissues were found to be uniform even though there was an apparent tendency toward the less pronounced granulation and scarification processes in the animals implanted with the diamond-like carbon coating containing the dispersed nano-sized silver particles. In none of the groups, the animals exhibited statistically significant lymphoid tissue hyperplasia in the spleen which suggested the activation of the immune system in response to implantation. It is concluded that the PTFE-based fluoroplast F-4PM20 implants with the 5 nm thick DLC coating and a similar coating containing the dispersed nano-sized silver particles can be applied for middle ear reconstructive surgery, being a histologically compatible material that does not cause an inflammatory degenerative response of the tissues. PMID:25246203

  17. Strabismus Surgery

    MedlinePlus

    ... used. Some surgeons prescribe an antibiotic or combination antibiotic/steroid drop or ointment after surgery. More technical ... Screening Recommendations Loading... Most Common Searches Adult ...

  18. Impact of Soft Tissue Heterogeneity on Augmented Reality for Liver Surgery.

    PubMed

    Haouchine, Nazim; Cotin, Stephane; Peterlik, Igor; Dequidt, Jeremie; Lopez, Mario Sanz; Kerrien, Erwan; Berger, Marie-Odile

    2015-05-01

    This paper presents a method for real-time augmented reality of internal liver structures during minimally invasive hepatic surgery. Vessels and tumors computed from pre-operative CT scans can be overlaid onto the laparoscopic view for surgery guidance. Compared to current methods, our method is able to locate the in-depth positions of the tumors based on partial three-dimensional liver tissue motion using a real-time biomechanical model. This model permits to properly handle the motion of internal structures even in the case of anisotropic or heterogeneous tissues, as it is the case for the liver and many anatomical structures. Experimentations conducted on phantom liver permits to measure the accuracy of the augmentation while real-time augmentation on in vivo human liver during real surgery shows the benefits of such an approach for minimally invasive surgery. PMID:26357206

  19. Rhabdomyosarcoma: Surgery

    MedlinePlus

    ... is and what type of operation is done. Physical changes after surgery can range from little more than a scar to changes in appearance or in how some parts of the body function, which may require physical rehabilitation. For more on surgery as a treatment ...

  20. Refractive Surgery

    PubMed Central

    Kellum, Keith

    2000-01-01

    The concept of surgically altering the eye to correct refractive errors has been considered for hundreds of years, but only in the past 60 years has interest grown considerably due to the development of modern refractive surgery techniques such as astigmatic keratotomies to correct astigmatism induced by cataract surgery and future technologies currently being investigated. Modern refractive surgery is more involved than setting the correct parameters on the laser. Patient selection and examination, proper technique, and postoperative follow-up for potential complications are essential for a successful refractive procedure. Critical evaluation of new techniques is vital to avoid the pitfall of overly exuberant enthusiasm for new and unproven methods of refractive surgery. Kellum K. Refractive surgery. The Ochsner Journal 2000; 2:164-167. PMID:21765686

  1. Virtual reality in laparoscopic surgery.

    PubMed

    Uranüs, Selman; Yanik, Mustafa; Bretthauer, Georg

    2004-01-01

    Although the many advantages of laparoscopic surgery have made it an established technique, training in laparoscopic surgery posed problems not encountered in conventional surgical training. Virtual reality simulators open up new perspectives for training in laparoscopic surgery. Under realistic conditions in real time, trainees can tailor their sessions with the VR simulator to suit their needs and goals, and can repeat exercises as often as they wish. VR simulators reduce the number of experimental animals needed for training purposes and are suited to the pursuit of research in laparoscopic surgery. PMID:15747974

  2. Delivery of antifibroblast agents as adjuncts to filtration surgery. Part I--Periocular clearance of cobalt-57 bleomycin in experimental drug delivery: pilot study in the rabbit

    SciTech Connect

    Kay, J.S.; Litin, B.S.; Woolfenden, J.M.; Chvapil, M.; Herschler, J.

    1986-10-01

    Antitumor and antifibroblast agents show promise as adjuncts after glaucoma filtration surgery in reducing postoperative scarring and failure. We used nuclear imaging in rabbits to investigate periocular clearance of one such agent (/sup 57/Co-bleomycin). Sub-Tenon injection was compared to other delivery techniques. Our results showed that a collagen sponge and a silastic disc implant with a microhole prolonged drug delivery when compared to sub-Tenon injection alone or injection with a viscosity enhancing agent (0.5% sodium hyaluronate). We theorize that if an antifibroblast agent can be delivered in small and sustained amounts after filtration surgery, this may prolong bleb longevity and avoid unnecessary drug toxicity.

  3. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    NASA Astrophysics Data System (ADS)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  4. Brain surgery

    MedlinePlus

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  5. Rodding Surgery

    MedlinePlus

    ... Rods can be made of stainless steel or titanium. Regular rods do not expand. They have many ... v regular), the rod materials (stainless steel v titanium) and the age for a first rodding surgery. ...

  6. Cosmetic Surgery

    MedlinePlus

    ... defect or cosmetic flaw that has diminished their self-esteem over time. It's important to remember that cosmetic ... can create both physical changes and changes in self-esteem. But if you are seeking surgery with the ...

  7. Maze Surgery

    MedlinePlus

    ... for Hemodialysis Ventricular Assist Devices Maze Surgery | Share Electrical impulses in your heart muscle (the myocardium) cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located ...

  8. Thyroid Surgery

    MedlinePlus

    ... thyroid surgery, requiring treatment with thyroid hormone (see Hypothyroidism brochure ). This is especially true if you had ... Nodules Goiter Graves’ Disease Hashimoto’s Thyroiditis Hyperthyroidism (Overactive) Hypothyroidism (Underactive) Iodine Deficiency Low Iodine Diet Radioactive Iodine ...

  9. Open heart surgery

    MedlinePlus

    ... Heart bypass surgery (coronary artery bypass graft - CABG) Heart transplant Heart valve surgery Hypoplastic left heart repair Minimally ... Heart bypass surgery Heart bypass surgery - minimally invasive Heart transplant Heart valve surgery Hypoplastic left heart syndrome Patent ...

  10. Tennis elbow surgery

    MedlinePlus

    Lateral epicondylitis - surgery; Lateral tendinosis - surgery; Lateral tennis elbow - surgery ... Surgery to repair tennis elbow is usually an outpatient surgery. This means you will not stay in the hospital overnight. You will be ...

  11. Encenicline, an α7 Nicotinic Acetylcholine Receptor Partial Agonist, Reduces Immune Cell Infiltration in the Colon and Improves Experimental Colitis in Mice.

    PubMed

    Salaga, M; Blomster, L V; Piechota-Polańczyk, A; Zielińska, M; Jacenik, D; Cygankiewicz, A I; Krajewska, W M; Mikkelsen, J D; Fichna, Jakub

    2016-01-01

    The α7 pentamer nicotinic acetylcholine receptors (nAChRs) are a target in transduction of anti-inflammatory signals from the central nervous system to the gastrointestinal (GI) tract. The aim of this study was to investigate the anti-inflammatory action of the novel α7 nAChR partial agonist encenicline and to determine the mechanism underlying its activity. Anti-inflammatory activity of encenicline was evaluated using trinitrobenzenesulfonic acid (TNBS)- and dextran sulfate sodium (DSS)-induced models of colitis. Macroscopic score, ulcer score, colon length and thickness, as well as myeloperoxidase (MPO) activity were recorded. Immunohistochemistry (IHC) was used to measure the infiltration of immune cells in the colon. Furthermore, we employed flow cytometry to determine the effect of encenicline on frequencies of FoxP3(+) and interleukin (IL)-17A(+) T cells in the mouse colon. Encenicline attenuated TNBS- and DSS-induced colitis in mice via α7 nAChRs, as indicated by significantly reduced macroscopic parameters and MPO activity. Treatment with encenicline significantly reduced the infiltration of macrophages, neutrophils, and B cells in the colon of TNBS-treated animals, as indicated by IHC. In the TNBS model encenicline reduced the frequency of FoxP3(+) IL-17A(+) T cells in the colon. In the DSS-model treatment encenicline increased the frequency of FoxP3(+) T cells and reduced IL-17A(+) T cells. Stimulation of α7 nAChR with partial agonist encenicline alleviates colitis via alteration of the number and/or activation status of the immune cells in the gut, emphasizing a potential role of α7 nAChRs as a target for anticolitic drugs. PMID:26462538

  12. Determination of low-energy parameters of neutron-proton scattering on the basis of modern experimental data from partial-wave analyses

    SciTech Connect

    Babenko, V. A. Petrov, N. M.

    2007-04-15

    The triplet and singlet low-energy parameters in the effective-range expansion for neutron-proton scattering are determined by using the latest experimental data on respective phase shifts from the SAID nucleon-nucleon database. The results differ markedly from the analogous parameters obtained on the basis of the phase shifts of the Nijmegen group and contradict the parameter values that are presently used as experimental ones. The values found with the aid of the phase shifts from the SAID nucleon-nucleon database for the total cross section for the scattering of zero-energy neutrons by protons, {sigma}{sub 0} = 20.426 b, and the neutron-proton coherent scattering length, f = -3.755 fm, agree perfectly with experimental cross-section values obtained by Houk, {sigma}{sub 0} = 20.436 {+-} 0.023 b, and experimental scattering-length values obtained by Houk and Wilson, f = -3.756 {+-} 0.009 fm, but they contradict cross-section values of {sigma}{sub 0} = 20.491 {+-} 0.014 b according to Dilg and coherent-scattering-length values of f = -3.7409 {+-} 0.0011 fm according to Koester and Nistler.

  13. Experts' understanding of partial derivatives using the partial derivative machine

    NASA Astrophysics Data System (ADS)

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-12-01

    [This paper is part of the Focused Collection on Upper Division Physics Courses.] Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. In this paper, we report on an initial study of expert understanding of partial derivatives across three disciplines: physics, engineering, and mathematics. We report on the central research question of how disciplinary experts understand partial derivatives, and how their concept images of partial derivatives differ, with a focus on experimentally measured quantities. Using the partial derivative machine (PDM), we probed expert understanding of partial derivatives in an experimental context without a known functional form. In particular, we investigated which representations were cued by the experts' interactions with the PDM. Whereas the physicists and engineers were quick to use measurements to find a numeric approximation for a derivative, the mathematicians repeatedly returned to speculation as to the functional form; although they were comfortable drawing qualitative conclusions about the system from measurements, they were reluctant to approximate the derivative through measurement. On a theoretical front, we found ways in which existing frameworks for the concept of derivative could be expanded to include numerical approximation.

  14. Robotic Surgery

    PubMed Central

    Lanfranco, Anthony R.; Castellanos, Andres E.; Desai, Jaydev P.; Meyers, William C.

    2004-01-01

    Objective: To review the history, development, and current applications of robotics in surgery. Background: Surgical robotics is a new technology that holds significant promise. Robotic surgery is often heralded as the new revolution, and it is one of the most talked about subjects in surgery today. Up to this point in time, however, the drive to develop and obtain robotic devices has been largely driven by the market. There is no doubt that they will become an important tool in the surgical armamentarium, but the extent of their use is still evolving. Methods: A review of the literature was undertaken using Medline. Articles describing the history and development of surgical robots were identified as were articles reporting data on applications. Results: Several centers are currently using surgical robots and publishing data. Most of these early studies report that robotic surgery is feasible. There is, however, a paucity of data regarding costs and benefits of robotics versus conventional techniques. Conclusions: Robotic surgery is still in its infancy and its niche has not yet been well defined. Its current practical uses are mostly confined to smaller surgical procedures. PMID:14685095

  15. Laparoscopic sleeve gastrectomy in partial situs inversus

    PubMed Central

    Borude, S; Jadhav, S; Shaikh, T; Nath, SR

    2012-01-01

    Laparoscopic surgery in a patient with Partial Situs Inversus may pose interesting challenges to the surgeon. Here we report a case of a morbidly obese young female with partial situs inversus who underwent Laparoscopic Vertical Sleeve Gastrectomy (LSG). The peri-operative challenges very many and these have been enumerated. The mirror image approach is recommended in such cases for a successful surgery which was not employed in this case. Postoperative barium swallow was normal and the patient has been on regular follow up. PMID:24960136

  16. Study of hemorheological parameters following partial hepatectomy in rats with chronic aluminium intoxication.

    PubMed

    Contini, María del Carmen; Mahieu, Stella; Bazzoni, Graciela; Bernal, Claudio A; Carnovale, Cristina E

    2006-01-01

    The aim of our work was to analyze the hemorheological parameters following partial hepatectomy in rats with chronic Al-intoxication (Al). Male Wistar rats were randomly assigned into four experimental groups (n=6 each one): Sham (rats subjected to simulated surgery); Al+Sham; Partial Hepatectomy (animals subjected to 65% liver resection) and Al+Partial Hepatectomy. Our results show that both Partial Hepatectomy and Al treatment produce a decrease of plasma cholesterol level, which showed a negative association with Rigidity Index increase (r(s)=-0.6475, p<0.05). The increase of Rigidity Index observed in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy could be related to the increase of the proportion of non-discocytic erythrocytes, particularly stomatocytes, which determines a diminution of the Morphological Index. In the Altreated groups, greater changes in Rigidity Index and Morphological Index were observed. The relative viscosity of blood at a standard haematocrit of 40% was increased in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy as compared to Sham, due to erythrocyte rigidity. On the other hand, we observed that the increase of plasma fibrinogen concentration correlates with augmentation of plasma viscosity (r(s)=0.689, p=0.004) for all the experimental groups studied. The results indicate that both administration of Al and Partial Hepatectomy induce microcytic hypocromic anaemia in the rats reflected by a significant decrease of haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. From these results, we conclude that in partially hepatectomized, Al-overloaded rats the decrease in erythrocyte deformability may be an important factor leading to the installation of anaemia. PMID:17148841

  17. Partially coherent ultrafast spectrography

    NASA Astrophysics Data System (ADS)

    Bourassin-Bouchet, C.; Couprie, M.-E.

    2015-03-01

    Modern ultrafast metrology relies on the postulate that the pulse to be measured is fully coherent, that is, that it can be completely described by its spectrum and spectral phase. However, synthesizing fully coherent pulses is not always possible in practice, especially in the domain of emerging ultrashort X-ray sources where temporal metrology is strongly needed. Here we demonstrate how frequency-resolved optical gating (FROG), the first and one of the most widespread techniques for pulse characterization, can be adapted to measure partially coherent pulses even down to the attosecond timescale. No modification of experimental apparatuses is required; only the processing of the measurement changes. To do so, we take our inspiration from other branches of physics where partial coherence is routinely dealt with, such as quantum optics and coherent diffractive imaging. This will have important and immediate applications, such as enabling the measurement of X-ray free-electron laser pulses despite timing jitter.

  18. Partially coherent ultrafast spectrography

    PubMed Central

    Bourassin-Bouchet, C.; Couprie, M.-E.

    2015-01-01

    Modern ultrafast metrology relies on the postulate that the pulse to be measured is fully coherent, that is, that it can be completely described by its spectrum and spectral phase. However, synthesizing fully coherent pulses is not always possible in practice, especially in the domain of emerging ultrashort X-ray sources where temporal metrology is strongly needed. Here we demonstrate how frequency-resolved optical gating (FROG), the first and one of the most widespread techniques for pulse characterization, can be adapted to measure partially coherent pulses even down to the attosecond timescale. No modification of experimental apparatuses is required; only the processing of the measurement changes. To do so, we take our inspiration from other branches of physics where partial coherence is routinely dealt with, such as quantum optics and coherent diffractive imaging. This will have important and immediate applications, such as enabling the measurement of X-ray free-electron laser pulses despite timing jitter. PMID:25744080

  19. Carotid artery surgery

    MedlinePlus

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... through the catheter around the blocked area during surgery. Your carotid artery is opened. The surgeon removes ...

  20. Nose Surgery

    MedlinePlus

    ... and expand the nasal passages. Treatments include injection, freezing, and partial removal. Allergies, too, can cause internal ... evaluating your injury as the swelling recedes. (Apply ice while waiting to see the doctor.) What's most ...

  1. Preprosthetic Surgery.

    PubMed

    Ephros, Hillel; Klein, Robert; Sallustio, Anthony

    2015-08-01

    Preprosthetic oral and maxillofacial surgery has changed dramatically over the last 3 decades. Surgical preparation for dentures has been displaced by site development for implants. Nonetheless, there is still a role to play for several preprosthetic procedures. In this article, historical context is provided, enduring concepts are reviewed, and procedures that remain relevant are described and discussed. PMID:26231818

  2. Arthroscopic Surgery.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Arthroscopic surgery (or microsurgery) is a significant breakthrough in treating knee injuries. Its applications range from basic diagnosis to arthroscopic menisectomy, although its use in some procedures is still highly controversial. Many surgeons perform the diagnostic procedure, but follow this with the conventional surgical approach.…

  3. Cosmetic surgery.

    PubMed Central

    Harris, D. L.

    1989-01-01

    The psychotherapeutic nature of cosmetic surgery is emphasised by outlining the range of symptoms from which patients suffer and by explaining the sequence of psychological reactions which cause them. The principles which govern the selection of patients are defined. A brief account of each of the main cosmetic operations is given together with notes on their limitations and risks. PMID:2589786

  4. Cardiac Surgery

    PubMed Central

    Weisse, Allen B.

    2011-01-01

    Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of coronary artery bypass grafting greatly aided the treatment of coronary heart disease. Cardiac transplantation, attempts to use the total artificial heart, and the application of ventricular assist devices have brought us to the present day. Although progress in the field of cardiovascular surgery appears to have slowed when compared with the halcyon times of the past, substantial challenges still face cardiac surgeons. It can only be hoped that sufficient resources and incentive can carry the triumphs of the 20th century into the 21st. This review covers past developments and future opportunities in cardiac surgery. PMID:22163121

  5. Experimental test of postfire management in pine forests: impact of salvage logging versus partial cutting and nonintervention on bird-species assemblages.

    PubMed

    Castro, Jorge; Moreno-Rueda, Gregorio; Hódar, José A

    2010-06-01

    There is an intense debate about the effects of postfire salvage logging versus nonintervention policies on regeneration of forest communities, but scant information from experimental studies is available. We manipulated a burned forest area on a Mediterranean mountain to experimentally analyze the effect of salvage logging on bird-species abundance, diversity, and assemblage composition. We used a randomized block design with three plots of approximately 25 ha each, established along an elevational gradient in a recently burned area in Sierra Nevada Natural and National Park (southeastern Spain). Three replicates of three treatments differing in postfire burned wood management were established per plot: salvage logging, nonintervention, and an intermediate degree of intervention (felling and lopping most of the trees but leaving all the biomass). Starting 1 year after the fire, we used point sampling to monitor bird abundance in each treatment for 2 consecutive years during the breeding and winter seasons (720 censuses total). Postfire burned-wood management altered species assemblages. Salvage logged areas had species typical of open- and early-successional habitats. Bird species that inhabit forests were still present in the unsalvaged treatments even though trees were burned, but were almost absent in salvage-logged areas. Indeed, the main dispersers of mid- and late-successional shrubs and trees, such as thrushes (Turdus spp.) and the European Jay (Garrulus glandarius) were almost restricted to unsalvaged treatments. Salvage logging might thus hamper the natural regeneration of the forest through its impact on assemblages of bird species. Moreover, salvage logging reduced species abundance by 50% and richness by 40%, approximately. The highest diversity at the landscape level (gamma diversity) resulted from a combination of all treatments. Salvage logging may be positive for bird conservation if combined in a mosaic with other, less-aggressive postfire

  6. African Adders: Partial Characterization of Snake Venoms from Three Bitis Species of Medical Importance and Their Neutralization by Experimental Equine Antivenoms

    PubMed Central

    Paixão-Cavalcante, Danielle; Kuniyoshi, Alexandre K.; Portaro, Fernanda C. V.; da Silva, Wilmar Dias; Tambourgi, Denise V.

    2015-01-01

    Background An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms. Methodology/Principal Findings The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1–7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested. Conclusion These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms. PMID:25643358

  7. [Surgery of brain metastases].

    PubMed

    Métellus, P; Reyns, N; Voirin, J; Menei, P; Bauchet, L; Faillot, T; Loiseau, H; Pallud, J; Guyotat, J; Mandonnet, E

    2015-02-01

    Surgical excision of brain metastases has been well evaluated in unique metastases. Two randomized phase III trial have shown that combined with adjuvant whole brain radiotherapy, it significantly improves overall survival. However, even in the presence of multiple brain metastases, surgery may be useful. Also, even in lesions amenable to radiosurgery, surgical resection is preferred when tumors displayed cystic or necrotic aspect with important edema or when located in highly eloquent areas or cortico-subcortically. Furthermore, surgery may have a diagnostic role, in the absence of histological documentation of the primary disease, to rule out a differential diagnosis (brain abscess, lymphoma, primary tumor of the central nervous system or radionecrosis). Finally, the biological documentation of brain metastatic disease might be useful in situations where a specific targeted therapy can be proposed. Selection of patients who will really benefit from surgery should take into account three factors, clinical and functional status of the patient, systemic disease status and characteristics of intracranial metastases. Given the improved overall survival of cancer patients partially due to the advent of effective targeted therapies on systemic disease, a renewed interest has been given to the local treatment of brain metastases. Surgical resection currently represents a valuable tool in the armamentarium of brain metastases but has also become a diagnostic and decision tool that can affect therapeutic strategies in these patients. PMID:25640217

  8. Scoliosis surgery - child

    MedlinePlus

    Spinal curvature surgery - child; Kyphoscoliosis surgery - child; Video-assisted thoracoscopic surgery - child; VATS - child ... Before surgery, your child will receive general anesthesia. This will make ... and unable to feel pain during the operation. During ...

  9. Lung Carcinoid Tumor: Surgery

    MedlinePlus

    ... for lung carcinoid tumor symptoms Surgery to treat lung carcinoid tumors Surgery is the main treatment for ... often be cured by surgery alone. Types of lung surgery Different operations can be used to treat ( ...

  10. Surgery for Breast Cancer

    MedlinePlus

    ... Next Topic Breast-conserving surgery (lumpectomy) Surgery for breast cancer Most women with breast cancer have some type ... Relieve symptoms of advanced cancer Surgery to remove breast cancer There are two main types of surgery to ...

  11. LASIK - Laser Eye Surgery

    MedlinePlus

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ...

  12. Refractive corneal surgery - discharge

    MedlinePlus

    Nearsightedness surgery - discharge; Refractive surgery - discharge; LASIK - discharge; PRK - discharge ... You had refractive corneal surgery to help improve your vision. This surgery uses a laser to reshape your cornea. It corrects ...

  13. What Is Refractive Surgery?

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Find an Ophthalmologist Advanced ...

  14. Bloodless surgery in geriatric surgery.

    PubMed

    Guarino, Salvatore; Di Matteo, Filippo; Sorrenti, Salvatore; Greco, Roberto; Nardi, Matteo; Favoriti, Pasqualino; De Antoni, Enrico; Filippini, Angelo; Catania, Antonio

    2014-01-01

    In bloodless surgery a series of measures has to be implemented to reduce the perioperative need for transfusion of whole blood or its components. Jehovah's Witness are the most representative group of patients opting for bloodless surgery as their faith follows strict believes that prohibits receiving blood. Geriatric patients requiring bloodless surgery are even more delicate and represent a challenge for surgeons. The physiological response of the over 65 year population to decreased hemoglobin level is slower and less effective than in young and adult patients. Herby we describe the perioperative protocol implemented in our surgical Department offered to geriatric Jehovah's Witness patients. Preoperative optimization of the patients is the key step in the preparation period. Intraoperative anesthetic and surgical measures are also required along with a strict postoperative follow-up. From our experience, bloodless surgery is feasible in the geriatric population as long as it is performed in specialized centers where a multidisciplinary team is prepared to specifically manage this scenario. Rigorous patients selection and preparation are mandatory. PMID:25183638

  15. [Tumor surgery].

    PubMed

    Hausamen, J E

    2000-05-01

    Surgery is still the primary therapeutic approach in treatment of tumors in the head and neck area, dating back to the early nineteenth century. More than 150 years ago, hemimaxillectomies and mandibular resections as well as hemiglossectomies were already performed by leading surgeons. The block principle we are now following dates back to Crile, who also established the principle of cervical lymph node dissection. Ablative oncologic surgery has always been closely linked with plastic and reconstructive surgery, rendering radical surgical interventions possible without disfiguring patients. The development of facial reconstructive surgery proceeded in stages, in the first instance as secondary reconstruction using tube pedicled flaps. The change to the concept of primary reconstruction occurred via arterialized skin flaps and myocutaneous flaps to the widely accepted and performed free tissue transfer. Free bone grafting, inaugurated earlier and still representing the majority of bone grafting, has been supplemented for certain reconstructive purposes by free vascularized bone transfer from various donor sites. Although the five-year-survival rate of carcinoma of the oral cavity has remained unchanged in the past 30 years, distinctive improvements in tumor surgery can be recorded. This is primarily based on improved diagnostics such as modern imaging techniques and the refinement of surgical techniques. The DOSAK has worked out distinctive guidelines for effective ablative oncologic surgery. Surgical approaches offering wide exposure and carrying low morbidity play a decisive role in radical resections. For this reason, midfacial degloving offers an essential improvement for the resection of midface tumors, especially from an aesthetic point of view. Tumors situated deep behind the viscerocranium at the skull base can be clearly exposed either through a lateral approach following a temporary osteotomy of the mandibular ramus or a transmandibular, transmaxillar, or

  16. Comprehensive review on endonasal endoscopic sinus surgery

    PubMed Central

    Weber, Rainer K.; Hosemann, Werner

    2015-01-01

    Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3–4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment. PMID:26770282

  17. Are Electron Partial Waves Real

    NASA Astrophysics Data System (ADS)

    Yenen, O.; McLaughlin, K. W.

    2005-05-01

    Experiments determining the partial wave content of electrons are uncommon. The standard approach to partial wave expansion of the wavefunction of electrons often ignores their spin. In this non-relativistic approximation the partial waves are labeled by their orbital angular momentum quantum number, e.g. d-waves. As our previous work has shown, this non-relativistic approximation usually fails for photoelectrons. Partial waves should be further specified by their total angular momentum. With d-waves for example, one would need to distinguish between d3/2 and d5/2 partial waves. Although energetically degenerate, fully relativistic d3/2 and d5/2 partial waves of photoelectrons have fundamentally different angular distributions. Using experimental and theoretical methods we have developed, we obtain partial wave probabilities of photoelectrons from polarization measurements of ionic fluorescence. We found that for selected states of the residual ion, there are energy regions where the photoelectron is in a single partial wave with predictable angular distributions.

  18. Partial protection and abomasal cytokine expression in sheep experimentally infected with Haemonchus contortus and pre-treated with Taenia hydatigena vesicular concentrate.

    PubMed

    Buendía-Jiménez, J A; Muñoz-Guzmán, M A; Vega-López, M A; Cuenca-Verde, C; Martínez-Labat, J P; Cuéllar-Ordaz, J A; Alba-Hurtado, F

    2015-06-30

    The abomasal expression of IL-2, IL-4, IL-6, IL-10 and IFNγ in lambs experimentally infected with Haemonchus contortus and its relationship to protection induced by a Taenia hydatigena larvae vesicular concentrate (ThLVC) were evaluated. The lambs that were only infected with H. contortus larvae showed a worm burden greater (p<0.05) than the lambs that received ThLVC prior to infection. Moreover, the lambs that received ThLVC showed a greater (p<0.05) number of blood eosinophils than the lambs that did not receive the ThLVC. In general, the lambs that received ThLVC prior to infection had a greater amount of eosinophils and mast cells and higher in situ expression of IFNγ, IL-2, IL-4, IL-6 and IL-10 in the abomasal wall than the lambs that were infected with H. contortus only or that received ThLVC (p<0.05) only. A higher expression of IL-2 and IFNγ in the submucosa compared to the abomasal mucosa and a higher expression of IL-4 in the abomasal mucosa compared to the submucosa was observed (p<0.05). These results suggest that there is a Th1 type response in the abomasal submucosa and a Th2 type response in in the abomasal mucosa. The amount of eosinophils and mast cells and the in situ expression of IFNγ, IL-2, IL-4 and IL-6 in the abomasal walls were negatively correlated with the worm burden (p<0.05). These results suggest that ThLVC is a non-specific immune stimulator for the abomasal immune response, and it is likely that the protection observed is the result of this effect. PMID:25959643

  19. Image-guided spine surgery: state of the art and future directions

    PubMed Central

    Shafizadeh, Sven; Rixen, Dieter; Paffrath, Thomas; Bouillon, Bertil; Steinhausen, Eva S.; Baethis, Holger

    2009-01-01

    Navigation technology is a widely available tool in spine surgery and has become a part of clinical routine in many centers. The issue of where and when navigation technology should be used is still an issue of debate. It is the aim of this study to give an overview on the current knowledge concerning the technical capabilities of image-guided approaches and to discuss possible future directions of research and implementation of this technique. Based on a Medline search total of 1,462 publications published until October 2008 were retrieved. The abstracts were scanned manually for relevance to the topics of navigated spine surgery in the cervical spine, the thoracic spine, the lumbar spine, as well as ventral spine surgery, radiation exposure, tumor surgery and cost-effectivity in navigated spine surgery. Papers not contributing to these subjects were deleted resulting in 276 papers that were included in the analysis. Image-guided approaches have been investigated and partially implemented into clinical routine in virtually any field of spine surgery. However, the data available is mostly limited to small clinical series, case reports or retrospective studies. Only two RCTs and one metaanalysis have been retrieved. Concerning the most popular application of image-guided approaches, pedicle screw insertion, the evidence of clinical benefit in the most critical areas, e.g. the thoracic spine, is still lacking. In many other areas of spine surgery, e.g. ventral spine surgery or tumor surgery, image-guided approaches are still in an experimental stage. The technical development of image-guided techniques has reached a high level as the accuracies that can be achieved technically meet the anatomical demands. However, there is evidence that the interaction between the surgeon (‘human factor’) and the navigation system is a source of inaccuracy. It is concluded that more effort needs to be spend to understand this interaction. PMID:19763640

  20. Mechanisms of scale formation and carbon dioxide partial pressure influence. Part I. Elaboration of an experimental method and a scaling model.

    PubMed

    Gal, Jean-Yves; Fovet, Yannick; Gache, Nathalie

    2002-02-01

    Scale formation in industrial or domestic installations is still an important economic problem. The existence of a metastable domain for calcium carbonate supersaturated solutions and its breakdown are observed under conditions rarely well defined. In most cases it is the pH rise caused by the carbon dioxide loss that involves calcium carbonate precipitation. Before studying this problem, we suggest in this first part, a new model for the evolution of the calcocarbonic system that takes into account the hydrated forms of CaCO3: CaCO3 amorphous, CaCO3 x 6H2O (ikaite) and CaCO3 x H2O (monohydrate). According to this model, the precipitation of any one of these hydrated forms could be responsible for the breakdown of the metastable state. After this first step, the solids evolve into dehydrated forms. At first, the metastable domain spread of the calcium carbonate supersaturated solutions was studied by the elaboration of computer programs in which the formation of CaCO3(0)(aq) ion pairs was taken into account. These ion pairs are supposed to evolve through dehydration to form the various calcium carbonate solid form precursors. This thermodynamic study was then compared to the experimental methods of the critical pH. Here the pH rise was caused by adding sodium hydroxide under different conditions for sodium hydroxide addition speed, agitation mode and ageing of solutions. For the highest speed of sodium hydroxide addition, the CaCO3 ionic product reached the value of the amorphous calcium carbonate solubility product, and the reaction of the amorphous calcium carbonate precipitation was of the homogenous type. Decreasing the reagent's addition speed caused an extension of the titration time. Then, the breakdown of the metastable state was obtained with the CaCO3 x H2O heterogeneous precipitation. This clearly illustrates the probable ageing of the precursors of the solid states that are considered in this model. PMID:11827336

  1. Partially Withdrawn Nasotracheal Tube: An Alternative to the Nasal Trumpet.

    PubMed

    Park, Yong Hee; Choi, Young Jun; Choi, Won Cheul; Lee, Ui Lyong

    2015-01-01

    After 2-jaw surgery, difficulty in breathing through the mouth and the nose is common due to nasal airway obstruction, intraoral bleeding, and sometimes maxillomandibular fixation. A partially withdrawn nasotracheal tube can be used economically with equal efficacy to the nasopharyngeal airway to provide supplemental oxygen after 2-jaw surgery. PMID:26650496

  2. Experimental determination of dissolved CO2 content in nominally anhydrous andesitic melts at graphite/diamond saturation - Remobilization of deeply subducted reduced carbon via partial melts of MORB-like eclogite

    NASA Astrophysics Data System (ADS)

    Eguchi, J.; Dasgupta, R.

    2015-12-01

    Experimental phase relations of carbonated lithologies [1] and geochemistry of deep diamonds [2] suggest that deep recycling of carbon has likely been efficient for a significant portion of Earth's history. Both carbonates and organic carbon subduct into the mantle, but with gradual decrease of fO2 with depth [3] most carbon in deep mantle rocks including eclogite could be diamond/graphite [4]. Previous studies investigated the transfer of CO2 from subducted eclogite to the ambient mantle by partial melting in the presence of carbonates, i.e., by generation of carbonate-rich melts [5]. However, the transfer of carbon from subducted eclogite to the mantle can also happen, perhaps more commonly, by extraction of silicate partial melt in the presence of reduced carbon; yet, CO2 solubility in eclogite-derived andesitic melt at graphite/diamond saturation remains unconstrained. CO2content of eclogite melts is also critical as geochemistry of many ocean island basalts suggest the presence of C and eclogite in their source regions [6]. In the present study we determine CO2 concentration in a model andesitic melt [7] at graphite/diamond saturation at conditions relevant for partial melting of eclogite in the convecting upper mantle. Piston cylinder and multi anvil experiments were conducted at 1-6 GPa and 1375-1550 °C using Pt/Gr double capsules. Oxygen fugacity was monitored with Pt-Fe sensors in the starting mix. Completed experiments at 1-3 GPa show that CO2 concentration increases with increasing P, T, and fO2 up to ~0.3 wt%. Results were used to develop empirical and thermodynamic models to predict CO2 concentration in partial melts of graphite saturated eclogite. This allowed us to quantify the extent to which CO2 can mobilize from eclogitic heterogeneities at graphite/diamond saturated conditions. With estimates of eclogite contribution to erupted basaltic lavas, the models developed here allow us to put constraints on the flux of CO2 to mantle source regions

  3. Oncoplastic breast surgery: current strategies

    PubMed Central

    Piper, Merisa; Peled, Anne Warren

    2015-01-01

    The surgical management of breast cancer has dramatically evolved over the past 20 years, with oncoplastic surgery gaining increased popularity. This field of breast surgery allows for complete resection of tumor, preservation of normal parenchyma tissue, and the use of local or regional tissue for immediate breast reconstruction at the time of partial mastectomy. These techniques extend the options for breast conservation surgery, improve aesthetic outcomes, have high patient satisfaction and result in better control of tumor margins. This article will detail the approach to evaluating and treating patients undergoing oncoplastic reconstruction. Different oncoplastic approaches will be described and applied to an oncoplastic reconstructive algorithm. Surgical complications, oncologic outcomes and aesthetic outcomes are reviewed. PMID:26005647

  4. [Robotic surgery].

    PubMed

    Sándor, József; Haidegger, Tamás; Kormos, Katalin; Ferencz, Andrea; Csukás, Domokos; Bráth, Endre; Szabó, Györgyi; Wéber, György

    2013-10-01

    Due to the fast spread of laparoscopic cholecystectomy, surgical procedures have been changed essentially. The new techniques applied for both abdominal and thoracic procedures provided the possibility for minimally invasive access with all its advantages. Robots - originally developed for industrial applications - were retrofitted for laparoscopic procedures. The currently prevailing robot-assisted surgery is ergonomically more advantageous for the surgeon, as well as for the patient through the more precise preparative activity thanks to the regained 3D vision. The gradual decrease of costs of robotic surgical systems and development of new generations of minimally invasive devices may lead to substantial changes in routine surgical procedures. PMID:24144815

  5. High Productivity Implantation ''PARTIAL IMPLANT''

    SciTech Connect

    Hino, Masayoshi; Miyamoto, Naoki; Sakai, Shigeki; Matsumoto, Takao

    2008-11-03

    The patterned ion implantation 'PARTIAL IMPLANT' has been developed as a productivity improvement tool. The Partial Implant can form several different ion dose areas on the wafer surface by controlling the speed of wafer moving and the stepwise rotation of twist axis. The Partial Implant system contains two implant methods. One method is 'DIVIDE PARTIAL IMPLANT', that is aimed at reducing the consumption of the wafer. The Divide Partial Implant evenly divides dose area on one wafer surface into two or three different dose part. Any dose can be selected in each area. So the consumption of the wafer for experimental implantation can be reduced. The second method is 'RING PARTIAL IMPLANT' that is aimed at improving yield by correcting electrical characteristic of devices. The Ring Partial Implant can form concentric ion dose areas. The dose of wafer external area can be selected to be within plus or minus 30% of dose of wafer central area. So the electrical characteristic of devices can be corrected by controlling dose at edge side on the wafer.

  6. Bariatric Surgery

    PubMed Central

    2005-01-01

    Executive Summary Objective To conduct an evidence-based analysis of the effectiveness and cost-effectiveness of bariatric surgery. Background Obesity is defined as a body mass index (BMI) of at last 30 kg/m2.1 Morbid obesity is defined as a BMI of at least 40 kg/m2 or at least 35 kg/m2 with comorbid conditions. Comorbid conditions associated with obesity include diabetes, hypertension, dyslipidemias, obstructive sleep apnea, weight-related arthropathies, and stress urinary incontinence. It is also associated with depression, and cancers of the breast, uterus, prostate, and colon, and is an independent risk factor for cardiovascular disease. Obesity is also associated with higher all-cause mortality at any age, even after adjusting for potential confounding factors like smoking. A person with a BMI of 30 kg/m2 has about a 50% higher risk of dying than does someone with a healthy BMI. The risk more than doubles at a BMI of 35 kg/m2. An expert estimated that about 160,000 people are morbidly obese in Ontario. In the United States, the prevalence of morbid obesity is 4.7% (1999–2000). In Ontario, the 2004 Chief Medical Officer of Health Report said that in 2003, almost one-half of Ontario adults were overweight (BMI 25–29.9 kg/m2) or obese (BMI ≥ 30 kg/m2). About 57% of Ontario men and 42% of Ontario women were overweight or obese. The proportion of the population that was overweight or obese increased gradually from 44% in 1990 to 49% in 2000, and it appears to have stabilized at 49% in 2003. The report also noted that the tendency to be overweight and obese increases with age up to 64 years. BMI should be used cautiously for people aged 65 years and older, because the “normal” range may begin at slightly above 18.5 kg/m2 and extend into the “overweight” range. The Chief Medical Officer of Health cautioned that these data may underestimate the true extent of the problem, because they were based on self reports, and people tend to over-report their

  7. The impact of laser ablation on optical soft tissue differentiation for tissue specific laser surgery-an experimental ex vivo study

    PubMed Central

    2012-01-01

    Background Optical diffuse reflectance can remotely differentiate various bio tissues. To implement this technique in an optical feedback system to guide laser surgery in a tissue-specific way, the alteration of optical tissue properties by laser ablation has to be taken into account. It was the aim of this study to evaluate the general feasibility of optical soft tissue differentiation by diffuse reflectance spectroscopy under the influence of laser ablation, comparing the tissue differentiation results before and after laser intervention. Methods A total of 70 ex vivo tissue samples (5 tissue types) were taken from 14 bisected pig heads. Diffuse reflectance spectra were recorded before and after Er:YAG-laser ablation. The spectra were analyzed and differentiated using principal component analysis (PCA), followed by linear discriminant analysis (LDA). To assess the potential of tissue differentiation, area under the curve (AUC), sensitivity and specificity was computed for each pair of tissue types before and after laser ablation, and compared to each other. Results Optical tissue differentiation showed good results before laser exposure (total classification error 13.51%). However, the tissue pair nerve and fat yielded lower AUC results of only 0.75. After laser ablation slightly reduced differentiation results were found with a total classification error of 16.83%. The tissue pair nerve and fat showed enhanced differentiation (AUC: 0.85). Laser ablation reduced the sensitivity in 50% and specificity in 80% of the cases of tissue pair comparison. The sensitivity of nerve–fat differentiation was enhanced by 35%. Conclusions The observed results show the general feasibility of tissue differentiation by diffuse reflectance spectroscopy even under conditions of tissue alteration by laser ablation. The contrast enhancement for the differentiation between nerve and fat tissue after ablation is assumed to be due to laser removal of the surrounding lipid-rich nerve

  8. Extraocular muscle injury during endoscopic sinus surgery: an ophthalmologic perspective.

    PubMed

    Park, K-A; Oh, S Y

    2016-05-01

    PurposeThe purpose of this study is to describe the clinical characteristics and treatment results of medial rectus muscle (MR) transection incurred during endoscopic sinus surgery.MethodsThis retrospective study included 16 patients with MR transection incurred during endoscopic sinus surgery between 1994 and 2015. The operative notes of the surgical procedure, the pattern of strabismus, the type of muscle injury, the type of corrective strabismus surgery, and the surgical outcomes were reviewed.ResultsNine patients had partial resection of MR and seven patients had complete transection of MR, resulting from an injury incurred during endoscopic sinus surgery. Three of the nine patients with partial resection injury were initially diagnosed as complete resection and subsequently re-diagnosed as partial resection in a review of the images during this study. Five of the nine patients with partial MR resection underwent only simple recession/resection surgery. Patients with complete MR transection underwent muscle transposition or globe fixation surgeries and often multiple operations were required.ConclusionsThe results of this study showed that the treatment strategies could vary depending on the nature of muscle injury. In cases with complete transection, muscle transposition or globe fixation surgeries are often required, with multiple operations. However, partial muscle resection with only simple recession/resection surgery shows a favorable outcome in many cases. The use of proper imaging techniques, a thorough review of the images with various planes, and close follow-up are important for determining the nature of the muscle injury. PMID:26892024

  9. Complete characterization of partially coherent and partially polarized optical fields.

    PubMed

    Basso, Gabriel; Oliveira, Luimar; Vidal, Itamar

    2014-03-01

    We suggest a method to access the second-order, or two-point, Stokes parameters of a partially coherent and partially polarized Gaussian model optical field from an intensity interferometry experiment. Through a remarkably simple experimental arrangement, it is possible to measure the two-point and one-point Stokes parameters simultaneously, allowing the reconstruction of the coherence matrix and the polarization matrix, thus completely characterizing the optical field both statistically and locally on the observation plane. Developments, automation, and applications are pointed out. PMID:24690711

  10. Robotic Surgery

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The Automated Endoscopic System for Optimal Positioning, or AESOP, was developed by Computer Motion, Inc. under a SBIR contract from the Jet Propulsion Lab. AESOP is a robotic endoscopic positioning system used to control the motion of a camera during endoscopic surgery. The camera, which is mounted at the end of a robotic arm, previously had to be held in place by the surgical staff. With AESOP the robotic arm can make more precise and consistent movements. AESOP is also voice controlled by the surgeon. It is hoped that this technology can be used in space repair missions which require precision beyond human dexterity. A new generation of the same technology entitled the ZEUS Robotic Surgical System can make endoscopic procedures even more successful. ZEUS allows the surgeon control various instruments in its robotic arms, allowing for the precision the procedure requires.

  11. Coronary Artery Bypass Surgery

    MedlinePlus

    ... t help, you may need coronary artery bypass surgery. The surgery creates a new path for blood to flow ... more than one bypass. The results of the surgery usually are excellent. Many people remain symptom-free ...

  12. Pediatric heart surgery - discharge

    MedlinePlus

    ... reduced appetite Alternate Names Congenital heart surgery - discharge; Patent ductus arteriosus ligation - discharge; Hypoplastic left heart repair - ... of the aorta Congenital heart defect - corrective surgery Patent ductus arteriosus Pediatric heart surgery Tetralogy of Fallot ...

  13. Scoliosis surgery - child

    MedlinePlus

    Spinal curvature surgery - child; Kyphoscoliosis surgery - child; Video-assisted thoracoscopic surgery - child; VATS - child ... may also do the procedure using a special video camera. A surgical cut in the back is ...

  14. Laser surgery - skin

    MedlinePlus

    Surgery using a laser ... used is directly related to the type of surgery being performed and the color of the tissue ... Laser surgery can be used to: Close small blood vessels to reduce blood loss Remove warts , moles , sunspots, and ...

  15. Tennis elbow surgery - discharge

    MedlinePlus

    ... epicondylitis surgery - discharge; Lateral tendinosis surgery - discharge; Lateral tennis elbow surgery - discharge ... long as you are told. This helps ensure tennis elbow will not return. You may be prescribed ...

  16. Pediatric heart surgery

    MedlinePlus

    Heart surgery - pediatric; Heart surgery for children; Acquired heart disease; Heart valve surgery - children ... after the baby is born. For others, your child may be able to safely wait for months ...

  17. Cosmetic ear surgery

    MedlinePlus

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... 31. Thorne CH. Otoplasty. In: Neligan PC, ed. Plastic Surgery . 3rd ed. Philadelphia, PA: Elsevier Saunders; 2013:chap ...

  18. Cosmetic Plastic Surgery Statistics

    MedlinePlus

    2014 Cosmetic Plastic Surgery Statistics Cosmetic Procedure Trends 2014 Plastic Surgery Statistics Report Please credit the AMERICAN SOCIETY OF PLASTIC SURGEONS when citing statistical data or using ...

  19. Statistics and Ethics in Surgery and Anesthesia

    ERIC Educational Resources Information Center

    Gilbert, John P.; And Others

    1977-01-01

    Analyzes 46 medical research papers on the effects of innovative versus standard surgical procedures on the health of patients. Results reveal that innovations generally reduce complications. The ethics of experimental surgery are also discussed. (CP)

  20. Transoral Surgery

    PubMed Central

    Rock, Jack P.; Tomecek, Frank J.; Ross, Lawrence

    1993-01-01

    The transoral approaches have become commonplace in modern neurosurgical practice for treatment of ventral midline lesions of the clivus and upper cervical spine. Although the standard technique of transoral surgery is conceptually simple, anatomic relationships are not so readily appreciated. The present study was undertaken in an effort to define more clearly the midline anatomic relationships as they pertain to the standard transoral and transpalatine operations. The anatomic relationships involved in planning microsurgical transoral approaches were examined in 15 human cadavers. Landmarks approximating the midline of the skull base and the upper cervical spinal canal were defined to assist the surgeon's orientation. Measurements were made in axial, sagital, and parasagittal planes to various neurovascular structures in the posterior cranial fossa and upper cervical spinal canal. The study revealed that, for the standard transoral and transoral-transpalatine dissections, the carotid arteries, abducens nerves, interior petrosal sinuses, hypoglossal nerves, and vertebral arteries would be a greatest risk being 0.76, 1.06, 1.51, 1.34, and 1.52 cm from the midline at specified locations. The measurements and the computed tomography images provide a useful reference for the surgeon. ImagesFigure 1Figure 9 PMID:17170899

  1. Transoral robotic surgery (TORS) for laryngeal and hypopharyngeal cancers.

    PubMed

    Dziegielewski, Peter T; Kang, Stephen Y; Ozer, Enver

    2015-12-01

    Transoral robotic surgery (TORS) is increasingly used in laryngeal/hypopharyngeal cancer surgery. Ablative procedures described in these anatomical sites include: (i) supraglottic laryngectomy, (ii) total laryngectomy, (iii) glottic cordectomy, and (iv) partial pharyngectomy. TORS supraglottic laryngectomy remains the most commonly performed of these procedures. Initial oncologic and functional outcomes with these procedures are promising and comparable to other treatment options. As robotic instrumentation technology advances a rise in TORS laryngeal/hypopharyngeal surgery is anticipated. PMID:26266762

  2. Partial siamese twin as potential organ donor

    PubMed Central

    Kapoor, Rakesh; Maheshwari, Ruchir; Srivastava, Aneesh; Sharma, Raj K.

    2010-01-01

    During evaluation of a partial Siamese twin for removal of nonviable parasitic part in an 8-year-old male child, a fully functional kidney was found. The functional status of the extra kidney was found to be within acceptable limits for the purpose of transplant, which was subsequently done in a 24-year-old patient with end-stage renal disease. The recipient is healthy 19 months after the surgery. The possibility of using organs from a partial Siamese twin makes this a unique case report. PMID:20877612

  3. Partial (focal) seizure

    MedlinePlus

    ... Jacksonian seizure; Seizure - partial (focal); Temporal lobe seizure; Epilepsy - partial seizures ... Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff ... Practice . 7th ed. Philadelphia, PA: Elsevier; 2016:chap 101. ...

  4. Partial (focal) seizure

    MedlinePlus

    ... Jacksonian seizure; Seizure - partial (focal); Temporal lobe seizure; Epilepsy - partial seizures ... Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff RB, ... 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 67. ...

  5. Partial tooth gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  6. Cautious surgery for discoid menisci

    NASA Astrophysics Data System (ADS)

    Smith, Chadwick F.; Van Dyk, Eda; Jurgutis, John; Vangsness, C. Thomas

    1995-05-01

    Thirty patients were surgically treated for discoid menisci at our institution from 1972 to 1987. All developed Fairbank's changes if followed more than 5 years. Between 1980 and 1987 we saw 25 patients with menisci over 50% of the size of the femoral condyle by magnetic resonance imaging or arthrographic examination. Surgical criteria have been anteroposterior hypermobility and arthroscopic evidence of rupture in patients with disabling symptoms. Of the 21 patients undergoing surgery since 1980, 99 (43%) have developed Fairbank's changes, all having been treated by partial meniscectomy or meniscectomy plus posterior repair. Follow-up arthroscopy in five patients revealed distinctly abnormal but relatively stable menisci. Partial meniscectomy for discoid menisci by the Watanabe classification is recommended if symptoms are disabling and the menisci is significantly torn. Repair must be added if the posterior horn is unstable.

  7. Partial hepatectomy in mice.

    PubMed

    Nevzorova, Y A; Tolba, R; Trautwein, C; Liedtke, C

    2015-04-01

    The surgical procedure of two-thirds partial hepatectomy (PH) in rodents was first described more than 80 years ago by Higgins and Anderson. Nevertheless, this technique is still a state-of-the-art method for the community of liver researchers as it allows the in-depth analysis of signalling pathways involved in liver regeneration and hepatocarcinogenesis. The importance of PH as a key method in experimental hepatology has even increased in the last decade due to the increasing availability of genetically-modified mouse strains. Here, we propose a standard operating procedure (SOP) for the implementation of PH in mice, which is based on our experience of more than 10 years. In particular, the SOP offers all relevant background information on the PH model and provides comprehensive guidelines for planning and performing PH experiments. We provide established recommendations regarding optimal age and gender of animals, use of appropriate anaesthesia and biometric calculation of the experiments. We finally present an easy-to-follow step-by-step description of the complete surgical procedure including required materials, critical steps and postoperative management. This SOP especially takes into account the latest changes in animal welfare rules in the European Union but is still in agreement with current international regulations. In summary, this article provides comprehensive information for the legal application, design and implementation of PH experiments. PMID:25835741

  8. Robotic partial nephrectomy: current technique and outcomes.

    PubMed

    Wang, Liang; Lee, Benjamin R

    2013-09-01

    Over the past decade, management of the T1 renal mass has focused on nephron-sparing surgery. Robotic partial nephrectomy has played an increasing role in the technique of preserving renal function by decreasing warm ischemia time, as well as optimizing outcomes of hemorrhage and fistula. Robot-assisted partial nephrectomy is designed to provide a minimally-invasive nephron-sparing surgical option utilizing reconstructive capability, decreasing intracorporeal suturing time, technical feasibility and safety. Ultimately, its benefits are resulting in its dissemination across institutions. Articulated instrumentation and three-dimensional vision facilitate resection, collecting system reconstruction and renorrhaphy, leading to decreased warm ischemia time while preserving oncological outcomes. The aim of the present review was to present our surgical sequence and technique, as well as review the current status of robot-assisted partial nephrectomy. PMID:23635467

  9. Tissue holder for experimental and Demonstration Surgery

    NASA Technical Reports Server (NTRS)

    Kuchta, F. J.; Pavlik, J. B.; Vargo, D. J.; Winters, G. R.

    1972-01-01

    Development of device for holding anatomical tissues during operations is discussed. Device consists of plastic dish with hemispherical recess in center to hold excised eyes. Low vacuum applied to underside of recess insures holding of part.

  10. Partial knee replacement

    MedlinePlus

    ... are OK after surgery, including walking, swimming, tennis, golf, and biking. However, you should avoid high-impact ... important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy , ...

  11. Applications of Computational Modeling in Cardiac Surgery

    PubMed Central

    Lee, Lik Chuan; Genet, Martin; Dang, Alan B.; Ge, Liang; Guccione, Julius M.; Ratcliffe, Mark B.

    2014-01-01

    Although computational modeling is common in many areas of science and engineering, only recently have advances in experimental techniques and medical imaging allowed this tool to be applied in cardiac surgery. Despite its infancy in cardiac surgery, computational modeling has been useful in calculating the effects of clinical devices and surgical procedures. In this review, we present several examples that demonstrate the capabilities of computational cardiac modeling in cardiac surgery. Specifically, we demonstrate its ability to simulate surgery, predict myofiber stress and pump function, and quantify changes to regional myocardial material properties. In addition, issues that would need to be resolved in order for computational modeling to play a greater role in cardiac surgery are discussed. PMID:24708036

  12. Surgery for Peyronie's disease

    PubMed Central

    Levine, Laurence A; Larsen, Stephen M

    2013-01-01

    Peyronie's disease (PD) is most simply referred to as a fibrotic wound-healing disorder of the tunica albuginea. It is both a physically and psychologically devastating disorder that causes penile deformity, curvature, hinging, narrowing and shortening, which may compromise sexual function. Although a variety of non-surgical treatments have been suggested, none to date offer a reliable and effective correction of the penile deformity. As a result, surgery remains the gold standard treatment option, offering the most rapid and reliable treatment which will be the focus of this article. We review the preoperative evaluation, surgical algorithm, graft materials and postoperative management of PD. Outcomes for tunical shortening, tunical lengthening and penile prosthesis placement for penile straightening are reviewed. Tunica albuginea plication is the preferred method of straightening for men with adequate rigidity and less severe disease defined as curvature less than 70° without narrowing/hinging. Men who have more severe, complex deformity, but maintain strong preoperative erectile function should be considered candidates for straightening with plaque incision or partial excision and grafting. Finally, for those men who have inadequate rigidity and PD, penile prosthesis placement with straightening is the best approach to address both problems. PMID:23178395

  13. Laparoscopic retroperitoneoscopic nephrectomy and partial nephrectomy in children

    PubMed Central

    Al-hazmi, Hamdan H.; Farraj, Hamzeh M.

    2015-01-01

    Objectives: The aim was to evaluate our experience in the retroperitoneal laparoscopic approach in total and partial nephrectomies in children. Materials and Methods: We retrospectively reviewed the medical records of 41 patients who underwent retroperitoneal laparoscopic total or partial nephrectomies performed in our center from 2004 to 2012. We looked at the demographic data, age at surgery, indication, operative time, surgical complications, conversion to open surgery and operative complications. Results: Thirty-five total and six partial nephrectomies (upper pole) were performed. The mean age was 84 months (7-175). Vesicoureteric reflux, pelviureteric junction obstruction, and multicystic dysplastic kidney disease were the main underlying pathologies. The mean operative time was 158 min (60-280). There were no intraoperative complications (surgical and anesthetic), and no significant blood loss was observed. Conversion to open surgery was necessary in two cases caused by failure to progress due to difficult anatomy during the partial nephrectomies. No major postoperative complications were noted. The mean hospital stay was 2.5 days (1-5). A drain was used in 12 cases and was removed after a mean of 2 days. Conclusions: Laparoscopic retroperitoneoscopic renal surgery can be carried out safely and effectively in children. Still, this procedure is more challenging and requires an excellent image of the retroperitoneal space, especially when partial nephrectomies are concerned. PMID:25837722

  14. Cataract surgery - series (image)

    MedlinePlus

    Cataract surgery usually works very well. The operation has few risks, the pain and recovery period are short, ... improved. Ninety-five percent or more of all cataract surgeries result in improved vision.

  15. Periodontal Plastic Surgery

    MedlinePlus

    ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ...

  16. American Board of Surgery

    MedlinePlus

    ... How to Apply Certifying Exam Specialty Definition Surgical Critical Care Related Policies Exam Admissibility Policy Leave Policy Certifying ... Surgery About the Exam How to Apply Surgical Critical Care About the Exam How to Apply Hand Surgery ...

  17. Carotid artery surgery - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000238.htm Carotid artery surgery - discharge To use the sharing features on this page, please enable JavaScript. You had carotid artery surgery to restore proper blood flow to your ...

  18. Lasik eye surgery - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000525.htm Lasik eye surgery - discharge To use the sharing features on this page, please enable JavaScript. Lasik eye surgery permanently changes the shape of the cornea ( ...

  19. Ear Plastic Surgery

    MedlinePlus

    ... Meeting Calendar Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  20. Plastic Surgery for Teenagers

    MedlinePlus

    ... or severe acne and scarring. Teens frequently gain self-esteem and confidence when their physical problems are corrected. ... art as a helpful index of anxiety and self-esteem with plastic surgery. Plastic and Reconstructive Surgery 2002. ...

  1. Refractive corneal surgery - discharge

    MedlinePlus

    ... after surgery, it should be okay to use artificial tears. Check with your doctor. Do NOT wear contact lenses on the eye that had surgery, even if you have blurry vision. Do NOT use any makeup, creams, or lotions ...

  2. Pediatric heart surgery - discharge

    MedlinePlus

    ... discharge; Heart valve surgery - children - discharge; Heart surgery - pediatric - discharge; Heart transplant - pediatric - discharge ... Keane JF, Lock JE, Fyler DC, eds. Nadas' Pediatric Cardiology . 2nd ed. St. Louis, MO; WB Saunders; ...

  3. Cosmetic breast surgery - discharge

    MedlinePlus

    ... Higdon KK. Reduction mammoplasty. In: Neligan PC, ed. Plastic Surgery . 3rd ed. Philadelphia, PA: Elsevier; 2013:chap 8. ... Gabriel A. Breast augmentation. In: Neligan PC, ed. Plastic Surgery . 3rd ed. Philadelphia, PA: Elsevier; 2013:chap 2.

  4. Cosmetic ear surgery

    MedlinePlus

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  5. Hip fracture surgery

    MedlinePlus

    ... neck fracture repair; Trochanteric fracture repair; Hip pinning surgery; Osteoarthritis-hip ... You may receive general anesthesia before this surgery. This means ... spinal anesthesia. With this kind of anesthesia, medicine is ...

  6. Complications of Sinus Surgery

    MedlinePlus

    ... further intracranial surgeries. Impaired sense of taste or smell : The sense of smell usually improves after the procedure because airflow is ... in their voice after sinus surgery. Impairment of smell or taste: (see above) Infection: The most common ...

  7. Technology needs for corneal transplant surgery

    NASA Astrophysics Data System (ADS)

    Vaddavalli, Pravin K.; Yoo, Sonia H.

    2011-03-01

    Corneal transplant surgery has undergone numerous modifications over the years with improvements in technique, instrumentation and eye banking. The main goals of corneal transplantation are achieving excellent optical clarity with long-term graft survival. Penetrating, anterior and posterior lamellar surgery along with femtosecond laser technology have partially met these goals, but outcomes are often unpredictable and surgeon dependent. Technology to predictably separate stroma from Descemet's membrane, techniques to minimize endothelial cell loss, improvements in imaging technology and emerging techniques like laser welding that might replace suturing, eventually making corneal transplantation a refractively predictable procedure are on the wish list of the cornea surgeon.

  8. Complications in Eyelid Surgery.

    PubMed

    Karimnejad, Kaveh; Walen, Scott

    2016-05-01

    Eyelid surgery consists of challenging reconstructive and cosmetic procedures. Because of the complex anatomy and corresponding vital functions of the upper and lower eyelids, the avoidance of eyelid complications is of vital importance. Complications after eyelid surgery include basic complications (infection, granuloma) and vision-threatening complications. Preoperative history, physical examination, surgical planning, and meticulous surgical technique must be undertaken to prevent complications after eyelid surgery. In addition, patient knowledge, expectations, and motivations must be determined before surgery is performed. PMID:27105805

  9. Robotic liver surgery

    PubMed Central

    Leung, Universe

    2014-01-01

    Robotic surgery is an evolving technology that has been successfully applied to a number of surgical specialties, but its use in liver surgery has so far been limited. In this review article we discuss the challenges of minimally invasive liver surgery, the pros and cons of robotics, the evolution of medical robots, and the potentials in applying this technology to liver surgery. The current data in the literature are also presented. PMID:25392840

  10. Cavus Foot Surgery

    MedlinePlus

    ... Toes All Site Content AOFAS / FootCareMD / Treatments Cavus Foot Surgery Page Content What is a cavus foot? A cavus or high-arched foot may have ... related problems. What are the goals of cavus foot surgery? The main goal of surgery is to ...