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Sample records for 125-mm lbimduga likeketaste

  1. Advanced Applications Flight Equipment (AAFE) 125mm ultraviolet spectrometer

    NASA Technical Reports Server (NTRS)

    Schroeder, R. J.

    1973-01-01

    The conceptual work is reported for the 125 mm ultraviolet spectrometer to measure atmospheric ozone as a function of height, latitude, and time. The instrument is described along with the assembly, test, and calibration.

  2. Parametric Study On The CW Nd: YAG Laser Cutting Quality Of 1.25 mm Ultra Low Carbon Steel Sheets Using O2 Assist Gas

    SciTech Connect

    Salem, Hanadi G.; Abbas, Wafaa A.; Mansour, Mohy S.; Badr, Yehia A.

    2007-02-14

    There are many non-linear interaction factors responsible for the performance of the laser cutting process. Identification of the dominant factors that significantly affect the cut quality is important. In the current research, the gas pressure, laser power and scanning speed were selected as the cutting parameters. Effect of the cutting parameters on the cut quality was investigated, by monitoring the variation in hardness, oxide layer width and microstructural changes within the heat affected zone (HAZ). Results revealed that good quality cuts can be produced in ultra low carbon steel thin sheets, using CW Nd:YAG laser at a window of scanning speed ranging from 1100-1500 mm/min at a minimum heat input of 337watts under an assisting O2 gas pressure of 5 bar. Higher laser power resulted in either strengthening or softening in the HAZ surrounding the cut kerf. The oxide layer width is not affected by the energy density input but rather affected by the O2 gas pressure due to exothermal reaction.

  3. Parametric Study On The CW Nd: YAG Laser Cutting Quality Of 1.25 mm Ultra Low Carbon Steel Sheets Using O2 Assist Gas

    NASA Astrophysics Data System (ADS)

    Salem, Hanadi G.; Abbas, Wafaa A.; Mansour, Mohy S.; Badr, Yehia A.

    2007-02-01

    There are many non-linear interaction factors responsible for the performance of the laser cutting process. Identification of the dominant factors that significantly affect the cut quality is important. In the current research, the gas pressure, laser power and scanning speed were selected as the cutting parameters. Effect of the cutting parameters on the cut quality was investigated, by monitoring the variation in hardness, oxide layer width and microstructural changes within the heat affected zone (HAZ). Results revealed that good quality cuts can be produced in ultra low carbon steel thin sheets, using CW Nd:YAG laser at a window of scanning speed ranging from 1100-1500 mm/min at a minimum heat input of 337watts under an assisting O2 gas pressure of 5 bar. Higher laser power resulted in either strengthening or softening in the HAZ surrounding the cut kerf. The oxide layer width is not affected by the energy density input but rather affected by the O2 gas pressure due to exothermal reaction.

  4. Sub-micron, planarized, Nb-AlO(x)-Nb Josephson process for 125 mm wafers developed in partnership with Si technology

    NASA Astrophysics Data System (ADS)

    Ketchen, M. B.; Pearson, D.; Kleinsasser, A. W.; Hu, C.-K.; Smyth, M.; Logan, J.; Stawiasz, K.; Baran, E.; Jaso, M.; Ross, T.

    1991-11-01

    A new planarized all-refractory technology was demonstrated for low-Tc superconductivity (PARTS). With the exception of the Nb-AlO(x)-Nb trilayer preparation, the processing is done almost exclusively within an advanced Si technology fabrication facility. This approach made it possible to leverage highly off of existing state-of-the-art lithography, metal etching, materials deposition, and planarization capabilities. Using chemical-mechanical polish as the planarization technique Josephson junctions ranging in size from 0.5-100 sq microns were fabricated. Junction quality is excellent with the figure of merit Vm typically exceeding 70 mV. PARTS has yielded fully functional integrated Josephson devices including magnetometers, gradiometers, and soliton oscillators.

  5. THE RELATIONSHIP BETWEEN REAL-TIME AND TIME-INTEGRATED COARSE (2.5-10MM), INTERMEDIATE (1-2.5MM), AND FINE (<2.5MM) PARTICULATE MATTER IN THE LOS ANGELES BASIN

    EPA Science Inventory

    Population exposure to ambient particulate matter (PM) has received considerable attention due to the association between ambient particulate concentrations and mortality. Current toxicological and epidemiological studies and controlled human and animal exposures suggest that a...

  6. THE RELATIONSHIP BETWEEN REAL-TIME AND TIME-INTEGRATED COARSE (2.5-10MM), INTERMEDIATE (1-2.5MM), AND FINE (<2.5MM) PARTICULATE MATTER IN THE LOS ANGELES BASIN

    EPA Science Inventory

    Population exposure to ambient particulate matter (PM) has received considerable attention due to the association between ambient particulate concentrations and mortality. Current toxicological and epidemiological studies and controlled human and animal exposures suggest that a...

  7. Pulsed excimer laser processing for cost-effective solar cells

    NASA Technical Reports Server (NTRS)

    Wong, D.

    1984-01-01

    The goal was to demonstrate the cost effectiveness feasibility of fabricating 16% efficient solar cells on 125 mm diameter Cz wafers using pulsed excimer laser for junction formation, surface passivation, and front metallization.

  8. Parameter comparison of white matter diffusion tensor imaging (DTI) in rhesus macaques (Macaca mulatta)

    PubMed Central

    MO, Yin; CHAO, Fang; SONG, Ming; LIU, Ci-Rong; LIU, Hui-Lang; QIAN, Xi-Ying; ZHAO, Xu-Dong

    2014-01-01

    In this study, we analyzed diffusion tensor imaging (DTI) results of brain white matter in rhesus macaques (Macaca mulatta) with four different parameter settings and found that the sequence A (b=1 000 s/mm2, spatial resolution=1.25 mm×1.25 mm× 1.25 mm, numbers of direction=33, NSA=3) and B (b=800 s/mm2, spatial resolution=1.25 mm×1.25 mm×1.25 mm, numbers of direction=33, NSA=3) could accurately track coarse fibers. The fractional anisotropy (FA) derived from sequence C (b=1 000s/mm2, spatial resolution=0.55 mm×0.55 mm×2.5 mm, direction number=33, NSA=3) was too fuzzy to be used in tracking white matter fibers. By comparison, the high resolution and the FA with high contrast of gray matter and white matter derived from sequence D (b=800 s/mm2, spatial resolution=1.0 mm×1.0 mm ×1.0 mm, numbers of direction=33, NSA=3) qualified in its application in tracking both thick and thin fibers, making it an optimal DTI setting for rhesus macaques. PMID:24866488

  9. The effects of metamaterial on electromagnetic fields absorption characteristics of human eye tissues.

    PubMed

    Gasmelseed, Akram; Yunus, Jasmy

    2014-01-01

    The interaction of a dipole antenna with a human eye model in the presence of a metamaterial is investigated in this paper. The finite difference time domain (FDTD) method with convolutional perfectly matched layer (CPML) formulation have been used. A three-dimensional anatomical model of the human eye with resolution of 1.25 mm × 1.25 mm × 1.25 mm was used in this study. The dipole antenna was driven by modulated Gaussian pulse and the numerical study is performed with dipole operating at 900 MHz. The analysis has been done by varying the size and value of electric permittivity of the metamaterial. By normalizing the peak SAR (1 g and 10 g) to 1 W for all examined cases, we observed how the SAR values are not affected by the different permittivity values with the size of the metamaterial kept fixed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers

    SciTech Connect

    Antoniadis, H.

    2011-03-01

    Reported are the development and demonstration of a 17% efficient 25mm x 25mm crystalline Silicon solar cell and a 16% efficient 125mm x 125mm crystalline Silicon solar cell, both produced by Ink-jet printing Silicon Ink on a thin crystalline Silicon wafer. To achieve these objectives, processing approaches were developed to print the Silicon Ink in a predetermined pattern to form a high efficiency selective emitter, remove the solvents in the Silicon Ink and fuse the deposited particle Silicon films. Additionally, standard solar cell manufacturing equipment with slightly modified processes were used to complete the fabrication of the Silicon Ink high efficiency solar cells. Also reported are the development and demonstration of a 18.5% efficient 125mm x 125mm monocrystalline Silicon cell, and a 17% efficient 125mm x 125mm multicrystalline Silicon cell, by utilizing high throughput Ink-jet and screen printing technologies. To achieve these objectives, Innovalight developed new high throughput processing tools to print and fuse both p and n type particle Silicon Inks in a predetermined pat-tern applied either on the front or the back of the cell. Additionally, a customized Ink-jet and screen printing systems, coupled with customized substrate handling solution, customized printing algorithms, and a customized ink drying process, in combination with a purchased turn-key line, were used to complete the high efficiency solar cells. This development work delivered a process capable of high volume producing 18.5% efficient crystalline Silicon solar cells and enabled the Innovalight to commercialize its technology by the summer of 2010.

  11. Oviduct binding ability of porcine spermatozoa develops in the epididymis and can be advanced by incubation with caudal fluid.

    PubMed

    Peña, Santiago; Summers, Phillip; Gummow, Bruce; Paris, Damien B B P

    2015-06-01

    The sperm reservoir is formed when spermatozoa bind to the epithelium of the uterotubal junction and caudal isthmus of the oviduct. It is an important mechanism that helps synchronize the meeting of gametes by regulating untimely capacitation and polyspermic fertilization. This study investigated the influence of epididymal maturation and caudal fluid on the ability of spermatozoa to bind to oviduct epithelium using a model porcine oviduct explant assay. Spermatozoa from the rete testis, middle caput (E2-E3), middle corpus (E6), and cauda (E8) of Large White or Large White × Landrace boars aged 10 to 14 months were diluted in modified Androhep solution and incubated with porcine oviduct explants. Results reported in this study support our hypothesis that testicular spermatozoa need to pass through the regions of the epididymis to acquire the ability to bind to the oviduct. There was a sequential increase in the number of spermatozoa that bound to oviduct explants from the rete testis to caudal epididymis. Binding of caudal spermatozoa to isthmic explants was the highest (15.0 ± 1.2 spermatozoa per 1.25 mm(2), mean ± standard error of the mean; P ≤ 0.05) and lowest by spermatozoa from the rete testis (2.0 ± 0.3 per 1.25 mm(2)), and higher to isthmus from sows compared to gilts (35.8 ± 6.7 per 1.25 mm(2) vs. 14.8 ± 3.0 per 1.25 mm(2); P ≤ 0.05). Binding of ejaculated spermatozoa to porcine isthmus was higher than that for caudal spermatozoa (26.3 ± 1.4 per 1.25 mm(2) vs. 15.0 ± 0.8 per 1.25 mm(2); P ≤ 0.05) and higher to porcine than to bovine isthmus (26.3 ± 2.3 per 1.25 mm(2) vs. 18.8 ± 1.9 per 1.25 mm(2); P ≤ 0.05). Incubation of spermatozoa from the caput and corpus in caudal fluid increased the ability of spermatozoa to bind to the oviduct epithelium (P ≤ 0.05). In conclusion, the capacity of testicular spermatozoa to bind to the oviduct epithelium increases during their maturation in the epididymis and can be advanced by components of the caudal fluid.

  12. Radiation Resistance of Asporogenous Bacteria in Frozen Beef

    DTIC Science & Technology

    1976-03-01

    temperature was indicated as -300 C the range was +100 C. The temperature was monitored by means of a thermocouple and 2 appropriate recorder. When vacuum ... packaging was employed, sealing was at 125 mm mercury pressure. ,, Isolation procedure - Samples of ground beef were packaged in flexible polyethylene

  13. Design optimization of liquid scintillator cosmic-ray veto detector with BBQ shifter

    SciTech Connect

    Kruse, H.W.; Egdorf, S.S.; Simmons, D.F.

    1981-10-01

    Certain design characteristics of a liquid scintillator detector for charged cosmic particles, have been studied. These include evaluation of scintillator emission spectra, absorption in various thicknesses of BBQ shifter bars and effective transmission in long lengths of BBQ acrylic. For our BBQ sample, 12.5 mm thick with semicircular shape, the shifted light was transmitted with 2.0 m absorption length.

  14. Analysis of tracheid development in suppressed-growth Ponderosa Pine using the FPL ring profiler

    Treesearch

    C. Tim Scott; David W. Vahey

    2012-01-01

    The Ring Profiler was developed to examine the cross-sectional morphology of wood tracheids in a 12.5-mm core sample. The instrument integrates a specially designed staging apparatus with an optical imaging system to obtain high-contrast, high-resolution images containing about 200-500 tracheids. These images are further enhanced and analyzed to extract tracheid cross-...

  15. 49 CFR 571.202a - Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2009.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... restraint measurement device. Head restraint means a device that limits rearward displacement of a seated... mean square. (c) Determine the gap dimension by measuring the vertical straight line distance between... surface roughness of the cylinder is less than 1.6 µm, root mean square. (c) Determine if at least 125 mm...

  16. 49 CFR 571.202a - Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2009.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... restraint measurement device. Head restraint means a device that limits rearward displacement of a seated... made within the area. The surface roughness of the head form is less than 1.6 µm, root mean square. (c... cylinder is less than 1.6 µm, root mean square. (c) Determine if at least 125 mm of the cylinder can...

  17. When a Burr Can Not Penetrate the Calcified Lesion, Increasing Burr Size as Well as Decreasing Burr Size Can Be a Solution in Rotational Atherectomy.

    PubMed

    Sakakura, Kenichi; Taniguchi, Yousuke; Yamamoto, Kei; Wada, Hiroshi; Momomura, Shin-Ichi; Fujita, Hideo

    2017-03-02

    In rotational atherectomy (RA), several burr sizes are available, such as 1.25 mm, 1.5 mm, 1.75 mm, or ≥ 2.0 mm. It is important to select an appropriate burr size for each lesion because rotational atherectomy has several unique complications regarding burrs such as entrapment or perforation. When a burr cannot penetrate the lesion, downsizing of the burr is generally recommended. Also, if the smallest burr (1.25 mm) cannot penetrate the lesion, a change to a more supportive or larger French guiding catheter has been recommended. We describe the case of a 68 year-old female who was referred to our department for percutaneous coronary intervention to the calcified stenosis in the middle of the left anterior descending coronary artery. We used the smallest burr (1.25 mm) and a supportive 7 Fr guiding catheter to penetrate the lesion. However, the smallest burr could not pass the lesion even after 14 sessions (total ablation time: 339 seconds). We intentionally increased the burr size from 1.25 mm to 1.5 mm. The 1.5 mm burr successfully passed the lesion without any perforation or burr entrapment. In this manuscript, we discuss why increasing the burr size was successful for this severely calcified lesion that was not penetrated by the smallest burr.

  18. Observations of Select Neglected Double Stars

    NASA Astrophysics Data System (ADS)

    Hennig, Darren

    2007-01-01

    Measurements of four neglected doubles in the USNO Northern list, set I1 were measured using a 105mm refractor and the Celestron/Baader 12.5mm Microguide eyepiece.All Observations were made at the Brookside Astronomical Observatory (BAO), Edmonton, AB Canada: 53.492°N, 113.569°W, elev. 660m.

  19. Five degree-of-freedom control of an ultra-precision magnetically-suspended linear bearing. Ph.D. Thesis - MIT

    NASA Technical Reports Server (NTRS)

    Trumper, David L.; Slocum, A. H.

    1991-01-01

    The authors constructed a high precision linear bearing. A 10.7 kg platen measuring 125 mm by 125 mm by 350 mm is suspended and controlled in five degrees of freedom by seven electromagnets. The position of the platen is measured by five capacitive probes which have nanometer resolution. The suspension acts as a linear bearing, allowing linear travel of 50 mm in the sixth degree of freedom. In the laboratory, this bearing system has demonstrated position stability of 5 nm peak-to-peak. This is believed to be the highest position stability yet demonstrated in a magnetic suspension system. Performance at this level confirms that magnetic suspensions can address motion control requirements at the nanometer level. The experimental effort associated with this linear bearing system is described. Major topics are the development of models for the suspension, implementation of control algorithms, and measurement of the actual bearing performance. Suggestions for the future improvement of the bearing system are given.

  20. Brush-like Discharge Extending from a Grounded Electrode toward a Large-scale Charged Particle Cloud

    NASA Astrophysics Data System (ADS)

    Toki, Kenji; Migita, Shin-Ichi; Higashiyama, Yoshio

    Electrostatic discharge occurring between a large-scale charged particle cloud and a grounded spherical electrode was investigated. The charged particle cloud was formed by the cloud generators consisting of a blower and a corona charger. To cause electrostatic discharges between the cloud and a grounded electrode with reproducibility, the grounded spherical electrode with 100 or 125 mm in diameter was set at the outside of the cloud. The charge quantity in a charged particle cloud affected the number of discharges, discharge current and charge quantity. Under the condition of applied voltage to the corona charger of 19 kV, peak value of discharge current for the electrode of 100 and 125 mm diameter was 3.0 and 4.8 A and the charge quantities neutralized in a single discharge was 1.9 and 2.4 μC, respectively. The peak current depends strongly on the diameter of the spherical electrode.

  1. High temperature lubricant screening and systems studies

    NASA Technical Reports Server (NTRS)

    Jones, D. A.

    1973-01-01

    Four candidate lubricants for next generation aircraft gas turbine application were tested under open atmosphere conditions in a rig simulating an advanced engine 125 mm bore mainshaft thrust bearing position. Testing was conducted at speeds to 24,000 rpm (3,000,000 bearing DN), bearing ring temperature of 500 F, and with 1200 F air and 100 psi differential pressure across the seals installed in a dual tandem arrangement. Test bearing was a 125 mm bore split inner ring, outer race riding angular contact ball bearing under a 3280 lb. thrust load. One lubricant, a type 2 ester, performed extremely well. The mainshaft seal limited the performance. Numerous design improvements for this seal were indicated.

  2. Energy resolution measurements of LaBr 3:Ce scintillating crystals with an ultra-high quantum efficiency photomultiplier tube

    NASA Astrophysics Data System (ADS)

    Pani, R.; Cinti, M. N.; Scafè, R.; Pellegrini, R.; Vittorini, F.; Bennati, P.; Ridolfi, S.; Lo Meo, S.; Mattioli, M.; Baldazzi, G.; Pisacane, F.; Navarria, F.; Moschini, G.; Boccaccio, P.; Orsolini Cencelli, V.; Sacco, D.

    2009-10-01

    The performance of the new prototype of high quantum efficiency PMT (43% at 380 nm), Hamamatsu R7600U-200, was studied coupled to a LaBr 3:Ce crystal with the size of ∅12.5 mm×12.5 mm. The energy resolution results were compared with ones from two PMTs, Hamamatsu R7600U and R6231MOD, with 22% and 30% quantum efficiency (QE), respectively. Moreover, the photodetectors were equipped with tapered and un-tapered voltage dividers to study the non-linearity effects on pulse height distribution, due to very high peak currents induced in the PMT by the fast and intense light pulse of LaBr 3:Ce. The results show an energy resolution improvement with UBA PMT of about 20%, in the energy range of 80-662 keV, with respect to the BA one.

  3. Effect of copper addition at a rate of 4% weight on the machininability of ZA-21A1 cast alloy by CNC milling

    NASA Astrophysics Data System (ADS)

    Alqawabah, S. M. A.; Zaid, A. I. O.

    2014-06-01

    Little work is published on the effect of copper addition to zinc-aluminium ZA-21Al alloy on its surface quality machined by milling. In this paper, the effect of copper addition at a rate 4 % weight to the ZA-21Al alloy on its hardness and surface quality is investigated. It was found that the addition of 4% Cu resulted in 18.3% enhancement in microhardness whereas the mechanical characteristics were reduced (softening) about 14.5% at 0.2% strain. It was found that the best surface finish for this alloy before copper addition ZA21 was achieved at a feed rate of 100 mm/min and 1.25 mm depth of cut whereas the best surface finish for ZA21-4% Cu was achieved at feed rate 250 mm/min, 1600 rpm cutting velocity and 1.25 mm depth of cut.

  4. Influence of Weld Porosity on the Integrity of Marine Structures

    DTIC Science & Technology

    1989-02-01

    Bruce Mustain Mr. Alexander B . Stavov; U. S. MERCHANT MARINE ACADEMY NATIONAL ACADEMY OF SCIENCES Dr. C. B . Kim COMMITTEE ON MARINE STRUCTURE,, U. S...FIGURE 9(a). STRESS-LIFE PLOT SHOWING ACTUAL FATIGUE LIVES VERSUS PREDICTED FATIGUE LIVES OF WELDS CONTAINING POROSITY 32 FIGURE 9( b ). STRESS-LIFE PLOT...37 FIGURE 11. CLASS A AND CLASS B POROSITY CHART FOR 0.5 INCH (12.5 MM) THICK MATERIAL ....... ...................... ... 38 FIGURE 12

  5. Inter-reader variability in alternate forced choice studies

    NASA Astrophysics Data System (ADS)

    Huda, W.; Ogden, K. M.; Samei, E.; Scalzetti, E. M.; Lavallee, R. L.; Roskopf, M. L.

    2008-03-01

    In this study, we investigated differences in detection performance for twelve observers who each generated a CT contrast detail curve. An anthropomorphic newborn phantom's abdomen was imaged using a GE Light Speed CT scanner (4-slice). Alternate Forced Choice (AFC) experiments were performed with lesions sizes ranging from 2.5 to 12.5 mm to determine the intensity needed to achieve 92% correct (I 92%). Following training, twelve readers consisting of (2 technologists, 4 college students, 4 medical students, and 2 radiology residents) generated a single contrast detail curve. Eight readers produced approximately linear contrast detail curves while the remaining four readers required a second order polynomial fit because of reduced performance when detecting the largest (i.e., 12.5 mm) lesion. For the three smallest lesions, the coefficient of variation between the twelve readers was ~12%, which increases with increasing lesion size to ~23% for 12.5 mm lesion size. The ratio of the maximum I 92% to minimum I 92% values was ~1.6 for the smallest lesions, which increased to a factor of ~2.1 for the 12.5 mm lesion. Our results show that minimizing inter-reader variability in our AFC experiments could be achieved by eliminating the largest lesion that cause detection problems in one third of observers. The combined experimental data showed that the slope of the contrast detail curve was -0.42, lower than the value of -1.0 predicted by the Rose model, suggesting that the noise texture in CT associated with both quantum mottle and anatomic structure is an important factor affecting detection of these lesions.

  6. Unclassified Publications of Lincoln Laboratory 1 January-31 December 1993. Volume 19

    DTIC Science & Technology

    1993-12-31

    Nb SNAP Technology for 125 mm Wafers Developed in Partnership with Silicon Technology Rader , CM. Brown, EJR. Hollis, M.A. Smith, F.W. ffl Wang...1993, pp. 120-136 10182 Results from the Maine 1992 Toups, M.F. Foliage Penetration Experiment Ayasli, S. SPIE, Vol. 1942, Underground ...Point Source Response Hsu, C.C. Kong, J.A. Toups, M.F. Fleischman, J.G. Ayasli, S. Shin, R.T-I. SPEE, Vol. 1942, Underground and Obscured

  7. Improving the Efficiency and Efficacy of Glibenclamide in Limiting Progressive Hemorrhagic Necrosis Following Traumatic Spinal Cord Injury

    DTIC Science & Technology

    2013-10-01

    2009; 10: 928–934. 24 Tosun C, Koltz MT, Kurland DB, Ijaz H , Gurakar M , Schwartzbauer G et al. The Protective Effect of Glibenclamide in a Model of...were changed to create six different experimental groups: (1) Midline ( M ) severe (50 mm); (2) M moderate (25 mm); (3) M light (12.5 mm); (4...first 24 h after injury. The advancing hemorrhage results from delayed progressive catastrophic failure of the structural integrity of capillaries, a

  8. Experimental investigation for the performance of triangular fin array within a rectangular enclosure in natural convection dominated region

    NASA Astrophysics Data System (ADS)

    Dwivedi, Ankur; Das, Debasish

    2016-12-01

    This study investigates the performance of triangular fin array within a rectangular enclosure with heated bottom wall experimentally at a wide range of Rayleigh number (295214 ≤ Ra ≤ 773410) for different fin height values (12.5 mm ≤ L ≤ 37.5 mm) and fin spacing values (25 mm ≤ S ≤ 100 mm). A new correlation is also proposed for the Nusselt number which is demonstrated the satisfactory capture of the correct qualitative behaviour of system performance.

  9. TrueNorth: A High-Performance, Low-Power Neurosynaptic Processor for Multi-Sensory Perception, Action, and Cognition

    DTIC Science & Technology

    2016-03-31

    traditional processors on neural network algorithms [2]. Our efforts are now focused on both embedded and large-scale TrueNorth based systems , as...in Fig. 3. The IBM Neurosynaptic System 414 Evaluation Platform (NS1e) is targeted at embedded applications (dimensions: 125mm x 69mm, and weight...from embedded and embodied intelligence to large-scale perceptual analysis of streaming multi-sensory data, this massively parallel processor consumes

  10. 49 CFR 572.124 - Thorax assembly and test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., the peak force, measured by the probe in accordance with section 572.127, shall not be less than 1150 N (259 lbf) and not more than 1380 N (310 lbf). The peak force after 12.5 mm (0.5 in) of sternum... plot of force vs. deflection in paragraph (b)(1) of this section shall be not less than 65 percent but...

  11. 49 CFR 572.124 - Thorax assembly and test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., the peak force, measured by the probe in accordance with section 572.127, shall not be less than 1150 N (259 lbf) and not more than 1380 N (310 lbf). The peak force after 12.5 mm (0.5 in) of sternum... plot of force vs. deflection in paragraph (b)(1) of this section shall be not less than 65 percent but...

  12. 49 CFR 572.124 - Thorax assembly and test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., the peak force, measured by the probe in accordance with section 572.127, shall not be less than 1150 N (259 lbf) and not more than 1380 N (310 lbf). The peak force after 12.5 mm (0.5 in) of sternum... plot of force vs. deflection in paragraph (b)(1) of this section shall be not less than 65 percent but...

  13. Studies of Rain Erosion Mechanisms in a Range of IR Transmitting Ceramics Including Coated Samples

    DTIC Science & Technology

    1991-11-01

    strength of a full size window and that the surface finish achieved on the small discs can be reproduced ,in the larger discs.,Some results from the Multiple...125 mm diameter by 5.45 mm) zinc sulphide windows rather than small (25 mm or 50 mm diameter) test pieces. The agreement between. the results for the...inspection of the surfaces revealed areas where faint grinding and polishing marks were visible. The fracture stress results are given in Table I which

  14. Development of a 3D CT scanner using cone beam

    NASA Astrophysics Data System (ADS)

    Endo, Masahiro; Kamagata, Nozomu; Sato, Kazumasa; Hattori, Yuichi; Kobayashi, Shigeo; Mizuno, Shinichi; Jimbo, Masao; Kusakabe, Masahiro

    1995-05-01

    In order to acquire 3D data of high contrast objects such as bone, lung and vessels enhanced by contrast media for use in 3D image processing, we have developed a 3D CT-scanner using cone beam x ray. The 3D CT-scanner consists of a gantry and a patient couch. The gantry consists of an x-ray tube designed for cone beam CT and a large area two-dimensional detector mounted on a single frame and rotated around an object in 12 seconds. The large area detector consists of a fluorescent plate and a charge coupled device video camera. The size of detection area was 600 mm X 450 mm capable of covering the total chest. While an x-ray tube was rotated around an object, pulsed x ray was exposed 30 times a second and 360 projected images were collected in a 12 second scan. A 256 X 256 X 256 matrix image (1.25 mm X 1.25 mm X 1.25 mm voxel) was reconstructed by a high-speed reconstruction engine. Reconstruction time was approximately 6 minutes. Cylindrical water phantoms, anesthetized rabbits with or without contrast media, and a Japanese macaque were scanned with the 3D CT-scanner. The results seem promising because they show high spatial resolution in three directions, though there existed several point to be improved. Possible improvements are discussed.

  15. The effect of extremely narrow MLC leaf width on the plan quality of VMAT for prostate cancer.

    PubMed

    Park, Jong Min; Park, So-Yeon; Kim, Jin Ho; Carlson, Joel; Kim, Jung-In

    2016-06-23

    To investigate the effect of multi-leaf collimators (MLCs) with leaf width of 1.25 mm on the plan quality of volumetric modulated arc therapy (VMAT) for prostate cancer. A total of 20 patients with prostate cancer were retrospectively selected. Using a high definition MLC (HD MLC), primary and boost VMAT plans with two full arcs were generated for each patient (original plan). After that, by shifting the isocenter position of the 2nd arc by 1.25 mm in the cranio-caudal direction, we simulated fluences made with MLCs with leaf width of 1.25 mm. After shifting, primary and boost plans were generated for each patient (shifted plan). A sum plan was generated by summation of the primary and boost plan for each patient. Dose-volumetric parameters were calculated and compared. Both the homogeneity index (HI) and conformity index (CI) of the shifted plans were better than those of the original plans in primary plans (HI = 0.065 vs. 0.059 with p < 0.001 and CI = 1.056 vs. 1.044 with p = 0.006). Similarly, the shifted plans for the boost target volume showed better homogeneity and conformity than did the original plans (HI = 0.060 vs. 0.053 with p < 0.001 and CI = 1.015 vs. 1.009 with p < 0.001). The target mean dose of the original plans was closer to the prescription dose than that of the shifted plans in the case of sum plans (81.45 Gy vs. 81.12 Gy with p = 0.001). Use of extremely narrow MLCs could increase dose homogeneity and conformity of the target volume for prostate VMAT.

  16. [Usefulness of maximum intensity projections in low-radiation multislice CT lung cancer screening].

    PubMed

    Bastarrika Alemañ, G; Domínguez Echávarri, P D; Noguera Tajadura, J J; Arraiza Sarasa, M; Zudaire Díaz-Tejeiro, B; Zulueta Francés, J J

    2008-01-01

    To evaluate the diagnostic accuracy of non-overlapping 10-mm-thick axial maximum intensity projections (MIP) in the detection of pulmonary nodules in subjects participating in a lung cancer screening program (LCSP) using multislice computed tomography (MSCT) with a low dose of radiation. We evaluated 52 consecutive low-radiation MSCT studies in asymptomatic smokers included in an LCSP (1.25 mm axial images). Axial MIPs with 10mm slice thickness (30 images) were performed and evaluated retrospectively; readers were blind to the initial radiological report. All nodules detected were considered, regardless of their size or consistency. The standard of reference was determined by double reading and consensus for each nodule. A total of 162 pulmonary nodules (mean size: 3.9 mm, sd: 1.7) were detected. MIP reconstruction detected 150 nodules (S = 92.6%). The initial radiological evaluation detected 108 nodules (S = 66.7%). MIP reconstruction detected 54 (33.3%) nodules that were not reported initially (mean size: 3.4 mm; sd: 1.2) but failed to detect 12 (7.4%) of the nodules reported initially (mean size: 2.91 mm; sd: 0.8). MIP detected all 35 nodules > or = 5 mm, (S =100), whereas the initial radiological evaluation only detected 27 (S = 77%). MIP reconstruction enabled more of the nodules to be detected than the 1.25-mm conventional axial slices (p < 0.01). The introduction of non-overlapping 10-mm-thick axial MIP reconstructions in a low-radiation LCSP using MSCT enabled nodules more accurate and faster detection of pulmonary nodules in comparison with 1.25 mm conventional axial slices.

  17. Four- and Eight-Channel Aortoiliac CT Angiography: A Comparative Study

    SciTech Connect

    Karcaaltincaba, Musturay Foley, Dennis

    2005-04-15

    Purpose. To compare performance parameters, contrast material load and radiation dose in a patient cohort having aortoiliac CT angiography using 4- and 8-channel multidetector CT (MDCT) systems. Methods. Eighteen patients with abdominal aortic aneurysms underwent initial 4-channel and follow-up 8-channel MDCT angiography. Both the 4- and 8-channel MDCT systems utilized a matrix detector of 16 x 1.25 mm rows. Scan coverage included the abdominal aorta and iliac arteries to the level of the proximal femoral arteries. For 4-channel MDCT, nominal slice thickness and beam pitch were 1.25 mm and 1.5, respectively, and for 8-channel MDCT they were 1.25 mm and 1.35 or 1.65 respectively. Scan duration, iodinated contrast material load and mean aortoiliac attenuation were compared retrospectively. Comparative radiation dose measurements for 4- and 8-channel MDCT were obtained using a multiple scan average dose technique on an abdominal phantom. Results. Compared with 4-channel MDCT, 8-channel MDCT aortoiliac angiography was performed with equivalent collimation, decreased contrast load (mean 45% decrease: 144 ml versus 83 ml of 300 mg iodine/ml contrast material) and decreased acquisition time (mean 51% shorter: 34.4 sec versus 16.9 sec) without a significant change in mean aortic enhancement (299 HU versus 300 HU, p > 0.05). Radiation dose was 2 rad for the 4-channel system and 2/1.5 rad for the 8-channel system at 1.35/1.65 pitch respectively. Conclusion. Compared with 4-channel MDCT, aortoiliac CT angiography with 8-channel MDCT produces equivalent z-axis resolution with decreased contrast load and acquisition time without increased radiation exposure.

  18. Output factor comparison of Monte Carlo and measurement for Varian TrueBeam 6 MV and 10 MV flattening filter-free stereotactic radiosurgery system.

    PubMed

    Cheng, Jason Y; Ning, Holly; Arora, Barbara C; Zhuge, Ying; Miller, Robert W

    2016-05-08

    The dose measurements of the small field sizes, such as conical collimators used in stereotactic radiosurgery (SRS), are a significant challenge due to many factors including source occlusion, detector size limitation, and lack of lateral electronic equilibrium. One useful tool in dealing with the small field effect is Monte Carlo (MC) simulation. In this study, we report a comparison of Monte Carlo simulations and measurements of output factors for the Varian SRS system with conical collimators for energies of 6 MV flattening filter-free (6 MV) and 10 MV flattening filter-free (10 MV) on the TrueBeam accelerator. Monte Carlo simulations of Varian's SRS system for 6 MV and 10 MV photon energies with cones sizes of 17.5 mm, 15.0 mm, 12.5 mm, 10.0 mm, 7.5 mm, 5.0 mm, and 4.0 mm were performed using EGSnrc (release V4 2.4.0) codes. Varian's version-2 phase-space files for 6 MV and 10 MV of TrueBeam accelerator were utilized in the Monte Carlo simulations. Two small diode detectors Edge (Sun Nuclear) and Small Field Detector (SFD) (IBA Dosimetry) were applied to measure the output factors. Significant errors may result if detector correction factors are not applied to small field dosimetric measurements. Although it lacked the machine-specific kfclin,fmsrQclin,Qmsr correction factors for diode detectors in this study, correction factors were applied utilizing published studies conducted under similar conditions. For cone diameters greater than or equal to 12.5 mm, the differences between output factors for the Edge detector, SFD detector, and MC simulations are within 3.0% for both energies. For cone diameters below 12.5 mm, output factors differences exhibit greater variations.

  19. Output factor comparison of Monte Carlo and measurement for Varian TrueBeam 6 MV and 10 MV flattening filter-free stereotactic radiosurgery system.

    PubMed

    Cheng, Jason Y; Ning, Holly; Arora, Barbara C; Zhuge, Ying; Miller, Robert W

    2016-05-01

    The dose measurements of the small field sizes, such as conical collimators used in stereotactic radiosurgery (SRS), are a significant challenge due to many factors including source occlusion, detector size limitation, and lack of lateral electronic equilibrium. One useful tool in dealing with the small field effect is Monte Carlo (MC) simulation. In this study, we report a comparison of Monte Carlo simulations and measurements of output factors for the Varian SRS system with conical collimators for energies of 6 MV flattening filter-free (6 MV) and 10 MV flattening filter-free (10 MV) on the TrueBeam accelerator. Monte Carlo simulations of Varian's SRS system for 6 MV and 10 MV photon energies with cones sizes of 17.5 mm, 15.0 mm, 12.5 mm, 10.0 mm, 7.5 mm, 5.0 mm, and 4.0 mm were performed using EGSnrc (release V4 2.4.0) codes. Varian's version-2 phase-space files for 6 MV and 10 MV of TrueBeam accelerator were utilized in the Monte Carlo simulations. Two small diode detectors Edge (Sun Nuclear) and Small Field Detector (SFD) (IBA Dosimetry) were applied to measure the output factors. Significant errors may result if detector correction factors are not applied to small field dosimetric measurements. Although it lacked the machine-specific kQclin,Qmsrfclin,fmsr correction factors for diode detectors in this study, correction factors were applied utilizing published studies conducted under similar conditions. For cone diameters greater than or equal to 12.5 mm, the differences between output factors for the Edge detector, SFD detector, and MC simulations are within 3.0% for both energies. For cone diameters below 12.5 mm, output factors differences exhibit greater variations. PACS number(s): 87.55.k, 87.55.Qr.

  20. A First Comparison of Millimeter Continuum and Mg ii Ultraviolet Line Emission from the Solar Chromosphere

    NASA Astrophysics Data System (ADS)

    Bastian, T. S.; Chintzoglou, G.; De Pontieu, B.; Shimojo, M.; Schmit, D.; Leenaarts, J.; Loukitcheva, M.

    2017-08-01

    We present joint observations of the Sun by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph (IRIS). Both millimeter/submillimeter-λ continuum emission and ultraviolet (UV) line emission originate from the solar chromosphere and both have the potential to serve as powerful and complementary diagnostics of physical conditions in this enigmatic region of the solar atmosphere. The observations were made of a solar active region on 2015 December 18 as part of the ALMA science verification effort. A map of the Sun’s continuum emission was obtained by ALMA at a wavelength of 1.25 mm (239 GHz). A contemporaneous map was obtained by IRIS in the Mg ii h doublet line at 2803.5 Å. While a clear correlation between the 1.25 mm brightness temperature T B and the Mg ii h line radiation temperature T rad is observed, the slope is <1, perhaps as a result of the fact that these diagnostics are sensitive to different parts of the chromosphere and that the Mg ii h line source function includes a scattering component. There is a significant difference (35%) between the mean T B (1.25 mm) and mean T rad (Mg ii). Partitioning the maps into “sunspot,” “quiet areas,” and “plage regions” we find the relation between the IRIS Mg ii h line T rad and the ALMA T B region-dependent. We suggest this may be the result of regional dependences of the formation heights of the IRIS and ALMA diagnostics and/or the increased degree of coupling between the UV source function and the local gas temperature in the hotter, denser gas in plage regions.

  1. Comparative study of the microvascular blood flow in the intestinal wall, wound contraction and fluid evacuation during negative pressure wound therapy in laparostomy using the V.A.C. abdominal dressing and the ABThera open abdomen negative pressure therapy system.

    PubMed

    Lindstedt, Sandra; Malmsjö, Malin; Hlebowicz, Joanna; Ingemansson, Richard

    2015-02-01

    This study aimed to compare the changes in microvascular blood flow in the small intestinal wall, wound contraction and fluid evacuation, using the established V.A.C. abdominal dressing (VAC dressing) and a new abdominal dressing, the ABThera open abdomen negative pressure therapy system (ABThera dressing), in negative pressure wound therapy (NPWT). Midline incisions were made in 12 pigs that were subjected to treatment with NPWT using the VAC or ABThera dressing. The microvascular blood flow in the intestinal wall was measured before and after the application of topical negative pressures of −50, −75 and −125mmHg using laser Doppler velocimetry. Wound contraction and fluid evacuation were also measured. Baseline blood flow was defined as 100% in all settings. The blood flow was significantly reduced to 64·6±6·7% (P <0·05) after the application of −50mmHg using the VAC dressing, and to 65·3±9·6% (P <0·05) after the application of −50mmHg using the ABThera dressing. The blood flow was significantly reduced to 39·6±6·7% (P <0·05) after the application of −125mmHg using VAC and to 40·5±6·2% (P <0·05) after the application of −125mmHg using ABThera. No significant difference in reduction in blood flow could be observed between the two groups. The ABThera system afforded significantly better fluid evacuation from the wound, better drainage of the abdomen and better wound contraction than the VAC dressing.

  2. Perirectal abscess following procedure for prolapsed haemorrhoids successfully managed with a combination of VAC sponge and Redivac systems.

    PubMed

    Durai, R; Ng, P C H

    2009-12-01

    Active drains, which work from negative pressure effect, are commonly used to drain closed airtight wounds. Higher negative pressure is used in vacuum assisted wound closure (VAC) (usually -125 mmHg) dressings and in Redivac system (usually -300 mmHg). As far as we know, combinations of Redivac and VAC have not been used. The authors describe a novel combination using the sponge of the VAC dressing and sealed Redivac system to drain an open rectal wound, consequence of a perforation after stapled haemorrhoidopexy.

  3. Astrometry of STF 2448 on the Mount Wilson 1.5 m Telescope with a Novel Video Eyepiece

    NASA Astrophysics Data System (ADS)

    Estrada, Reed; Ramos, Rafael; Wasson, Rick; Carro, Joseph; Kenney, John; Estrada, Chris; Hollman, Cassie; Wallen, Vera; Tassell, Noah; Genet, Russell

    2015-07-01

    The Mt. Wilson Double Star Workshop was organized to provide a hands-on educational and research opportunity for students and amateur astronomers to learn and carry out astrometric eyepiece measurements of double stars. Due to the unique operating characteristics of the Mt Wilson 1.5 meter telescope and the limited time available for observations, a Bell & Howell DNV16HDZ high definition video camera was adapted to a Celestron 12.5mm astronomic eyepiece to record the position and separation of double star STF2448. This paper records the results of the team's observations and their techniques used to record and analyze the data.

  4. Development of a Vertically Profiling, High-Resolution, Digital Still Camera System

    DTIC Science & Technology

    2000-09-30

    view. The volumes of the original uncropped images are indicated after each organism’s identity in parentheses. A. 16 mm long stomatopod ( mantis ... shrimp ) larva (image volume = 355ml); B 11.5 mm wide medusa (image volume = 355ml); C portunid crab megalopae 1.2-1.8 mm wide (image volume = 334ml); D...5.7 mm long isopod and 1.25 mm wide crab megalopa (image volume = 334 ml); E. 10.4 mm long postlarval penaeid shrimp (image volume = 598ml); F

  5. Fatigue Crack Closure - A Review

    DTIC Science & Technology

    1990-09-01

    gauge along the crack line. They used CCT speci- mens of high tensile strength steel ( HY80 ). The measured value of U was found to be a minimum at the...ultrasonic surface wave technique on 12.5mm thick specimens of 2024-T851, 2024-T351, Al 2219, Ti-6AI-4V and 17-4 PH steel . Most of the results were...medium and high strength steels . Exami- nation of the fracture surfaces suggested that raising the mean stress in low fracture toughness steels could

  6. Efficient second harmonic generation of a diode-laser-pumped CW Nd:YAG laser using monolithic MgO:LiNbO3 external resonant cavities

    NASA Technical Reports Server (NTRS)

    Kozlovsky, William J.; Nabors, C. D.; Byer, Robert L.

    1988-01-01

    56-percent efficient external-cavity-resonant second-harmonic generation of a diode-laser pumped, CW single-axial-mode Nd:YAG laser is reported. A theory of external doubling with a resonant fundamental is presented and compared to experimental results for three monolithic cavities of nonlinear MgO:LiNbO3. The best conversion efficiency was obtained with a 12.5-mm-long monolithic ring cavity doubler, which produced 29.7 mW of CW, single-axial model 532-nm radiation from an input of 52.5 mW.

  7. Design of rigid GRIN-endoscope with sapphire window and improved image quality

    NASA Astrophysics Data System (ADS)

    Fluder, Grzegorz; Voznesenskaya, Anna; Bakholdin, Alexey

    2015-05-01

    The possibilities of using gradient index (GRIN) lenses as the objective and relay lens in rigid endoscopic systems working in visible spectrum are investigated. The final aim of the project is to obtain a system providing diffraction limited image quality, which could be used for examining the gastrointestinal tract. This paper describes steps of the design of the system with working distance equal to 125 mm and angular field of view 25°. The diameter of the GRIN lenses is equal to 2,2 mm. Influence of the gradient of refractive index on the image quality is shown. Current results are analysed and future steps are described.

  8. Utilization of recycled glass as aggregate in controlled low-strength material (CLSM)

    SciTech Connect

    Ohlheiser, T.R.

    1998-10-01

    Incoming glass from curbside recycling programs is successfully being utilized as aggregate replacements. The colored glass that can not be used by local bottle manufacturers is crushed to a {1/2} in. (12.5 mm) material and used in various construction projects. The most successful use of processed glass aggregate (PGA) to date, has been in replacing up to 100% of the aggregate in controlled low-strength material (CLSM). It has proven to be successful and has gained acceptance by contractors in the Boulder, Colorado area.

  9. Evaluation of drilled-ball bearings at DN values to three million. 1: Variable oil flow tests

    NASA Technical Reports Server (NTRS)

    Holmes, P. W.

    1932-01-01

    Two 125-mm-bore solid ball bearings and two similar drilled ball bearings were operated at speeds up to 24,000 rpm (3.0 million DN) with a 13,000 newton (3000 lb) thrust load. The oil flow rate was varied from 0.045 to 0.121 kilograms per second (6 to 16 lb/min). The solid ball bearings operated satisfactorily over the entire range of conditions. The drilled ball bearing experienced cage rub with marginal lubrication at 0.045 kilograms per second (6 lb/min). The drilled ball bearing generally ran cooler than the solid ball bearings.

  10. Experimental evidence of the rear capture of aerosol particles by raindrops

    NASA Astrophysics Data System (ADS)

    Lemaitre, Pascal; Querel, Arnaud; Monier, Marie; Menard, Thibault; Porcheron, Emmanuel; Flossmann, Andrea I.

    2017-03-01

    This article presents new measurements of the efficiency with which aerosol particles of accumulation mode size are collected by a 1.25 mm sized raindrop. These laboratory measurements provide the link to reconcile the scavenging coefficients obtained from theoretical approaches with those from experimental studies. We provide here experimental proof of the rear capture mechanism in the flow around drops, which has a fundamental effect on submicroscopic particles. These experiments thus confirm the efficiencies theoretically simulated by Beard (1974). Finally, we propose a semi-analytical expression to take into account this essential mechanism to calculate the collection efficiency for drops within the rain size range.

  11. Measurement of Total Scatter Factor for Stereotactic Cones with Plastic Scintillation Detector

    PubMed Central

    Chaudhari, Suresh H; Dobhal, Rishabh; Kinhikar, Rajesh A.; Kadam, Sudarshan S.; Deshpande, Deepak D.

    2017-01-01

    Advanced radiotherapy modalities such as stereotactic radiosurgery (SRS) and image-guided radiotherapy may employ very small beam apertures for accurate localized high dose to target. Accurate measurement of small radiation fields is a well-known challenge for many dosimeters. The purpose of this study was to measure total scatter factors for stereotactic cones with plastic scintillation detector and its comparison against diode detector and theoretical estimates. Measurements were performed on Novalis Tx™ linear accelerator for 6MV SRS beam with stereotactic cones of diameter 6 mm, 7.5 mm, 10 mm, 12.5 mm, and 15 mm. The advantage of plastic scintillator detector is in its energy dependence. The total scatter factor was measured in water at the depth of dose maximum. Total scatter factor with plastic scintillation detector was determined by normalizing the readings to field size of 10 cm × 10 cm. To overcome energy dependence of diode detector for the determination of scatter factor with diode detector, daisy chaining method was used. The plastic scintillator detector was calibrated against the ionization chamber, and the reproducibility in the measured doses was found to be within ± 1%. Total scatter factor measured with plastic scintillation detector was 0.728 ± 0.3, 0.783 ± 0.05, 0.866 ± 0.55, 0.885 ± 0.5, and 0.910 ± 0.06 for cone sizes of 6 mm, 7.5 mm, 10 mm, 12.5 mm, and 15 mm, respectively. Total scatter factor measured with diode detector was 0.733 ± 0.03, 0.782 ± 0.02, 0.834 ± 0.07, 0.854 ± 0.02, and 0.872 ± 0.02 for cone sizes of 6 mm, 7.5 mm, 10 mm, 12.5 mm, and 15 mm, respectively. The variation in the measurement of total scatter factor with published Monte Carlo data was found to be −1.3%, 1.9%, −0.4%, and 0.4% for cone sizes of 7.5 mm, 10 mm, 12.5 mm, and 15 mm, respectively. We conclude that total scatter factor measurements for stereotactic cones can be adequately carried out with a plastic scintillation detector. Our results show a high level of consistency within our data and compared well with published data. PMID:28405102

  12. Modeling of the BNL photocathode gun with the code PARMELA

    NASA Astrophysics Data System (ADS)

    Parsa, Zohreh; Young, Lloyd

    1992-07-01

    We present an analysis of the electron beam emitted from the BNL laser driven photocathode injector operating at 2856 MHz. An analysis of the beam transported through the transport line to the entrance of the linac is also presented. Recent measurements of the photocathode laser shows that the pulse length has a sigma of ±5 ps and a transverse size of 1.25 mm. A Gaussian shape is assumed for the distribution in both the radial and time dependence of the laser beam. This is compared with the original design parameters of ±2 ps and 3 mm.

  13. Effect of pre-strain on ratcheting behavior of A668 Class D steel

    NASA Astrophysics Data System (ADS)

    Tripathy, S.; Mondal, A. K.; Dutta, K.

    2016-02-01

    The aim of this investigation is to study the effect pre-strain (0%, 2%, 4% and 8%) on ratcheting behavior of ASTM A668 Class D steel in different heat treatment conditions (normalized and hardened-tempered). Ratcheting tests were carried out at room temperature on cylindrical specimens having 12.5 mm gauge length and 6 mm gauge diameter. The results include reduced strain accumulation with increasing prestrain level due to work hardening of the pre-strained samples. Further, cyclic hardening takes place during ratcheting deformation.

  14. Efficient second harmonic generation of a diode-laser-pumped CW Nd:YAG laser using monolithic MgO:LiNbO3 external resonant cavities

    NASA Technical Reports Server (NTRS)

    Kozlovsky, William J.; Nabors, C. D.; Byer, Robert L.

    1988-01-01

    56-percent efficient external-cavity-resonant second-harmonic generation of a diode-laser pumped, CW single-axial-mode Nd:YAG laser is reported. A theory of external doubling with a resonant fundamental is presented and compared to experimental results for three monolithic cavities of nonlinear MgO:LiNbO3. The best conversion efficiency was obtained with a 12.5-mm-long monolithic ring cavity doubler, which produced 29.7 mW of CW, single-axial model 532-nm radiation from an input of 52.5 mW.

  15. Evaluation of residual strength of composite laminates damaged by low velocity impacts

    NASA Technical Reports Server (NTRS)

    Lal, K. M.

    1986-01-01

    This work presents the study of Low Velocity Transverse Impact damage of graphite-epoxy T300/5208 composite material. An energy dissipation model was developed to predict the residual strength from fracture mechanics concepts. The specimens, 100 mm diameter clamped plates, were impact damaged by a cantilever-type instrumented 1-inch diameter steel ball. This study was limited to impact velocity 6 m/sec. Rectangular strips, 50 mm x 125 mm, were cut from the impact-damaged specimens so that the impact damage zone was in the center of the strips. These strips were tested to obtain their residual strength. Predictions were compared with the test results.

  16. An Integrated Experimental and Computational Study of Heating due to Surface Catalysis under Hypersonic Conditions

    DTIC Science & Technology

    2012-08-01

    flowfield inside the VKI Plasmatron facility. The probe, shown in Fig. 21, consists of a copper plate with a 12.5 mm nose radius and can host a 152x30 mm...the low-high-low insert, with the finite volume code Cosmic [29]. 0 20 40 60 80 100 120 140 160 1300 1350 1400 1450 1500 1550 1600 1650 x, mm T , K...computations of the flow-field around the flat plate probe with the low-high-low catalytic insert have been performed with the code Cosmic [29]. Cosmic is a

  17. Rail accelerators for space transportation: An experimental investigation

    NASA Technical Reports Server (NTRS)

    Zana, L. M.; Kerslake, W. R.; Sturman, J. L.

    1986-01-01

    An experimental program was conducted at the Lewis Research Center with the objective of investigating the technical feasibility of rail accelerators for propulsion applications. Single-stage, plasma driven rail accelerators of small (4 by 6 mm) and medium (12.5 by 12.5 mm) bores were tested at peak accelerating currents of 50 to 450 kA. Streak-camera photography was used to provide a qualitative description of plasma armature acceleration. The effects of plasma blowby and varying bore pressure on the behavior of plasma armatures were studied.

  18. Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

    PubMed

    Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

    1998-08-01

    Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes.

  19. Focused beam control for ultrasound surgery with spherical-section phased array: sound field calculation and genetic optimization algorithm.

    PubMed

    Lu, Mingzhu; Wan, Mingxi; Xu, Feng; Wang, Xiaodong; Zhong, Hui

    2005-08-01

    This study aims at a sound field calculation for the spherical-section phased array and an optimization algorithm for the focus patterns of phased array ultrasound surgery. An efficient field calculation formula represented as an explicit expression is derived by the strategies of projection and binomial expansion. An optimization algorithm based on genetic algorithm is constructed by the suitable fitness function and the selection strategies. The simulation results of 256-element spherical-section phased array show the capability of controlling focus accurately and effectively with the combined method made up of the explicit expression method and the genetic optimization algorithm. The simulation results of single focus, multiple foci, on-axial focus, and off-axial focus further convince the feasibility of three-dimensional (3-D) focus steering with excellent acoustic performances. A single focus with the focus dimension of 1.25 mm x 1.25 mm x 7 mm and with the intensity of 6080 W/cm2 is formed. The multiple-focus pattern can enlarge the treatment volume 22 times larger than that of single focus with a sonication. In addition, a comparison between the explicit expression approach and the point source approach testifies to the applicability of the explicit expression approach. The experiment and simulation results of 16-element array actually confirm the feasibility of the combined method.

  20. Physiological selectivity and activity reduction of insecticides by rainfall to predatory wasps of Tuta absoluta.

    PubMed

    Barros, Emerson C; Bacci, Leandro; Picanco, Marcelo C; Martins, Júlio C; Rosado, Jander F; Silva, Gerson A

    2015-01-01

    In this study, we carried out three bioassays with nine used insecticides in tomato crops to identify their efficiency against tomato leaf miner Tuta absoluta, the physiological selectivity and the activity reduction of insecticides by three rain regimes to predatory wasps Protonectarina sylveirae and Polybia scutellaris. We assessed the mortality caused by the recommended doses of abamectin, beta-cyfluthrin, cartap, chlorfenapyr, etofenprox, methamidophos, permethrin, phenthoate and spinosad to T. absoluta and wasps at the moment of application. In addition, we evaluated the wasp mortality due to the insecticides for 30 days on plants that did not receive rain and on plants that received 4 or 125 mm of rain. Spinosad, cartap, chlorfenapyr, phenthoate, abamectin and methamidophos caused mortality higher than 90% to T. absoluta, whereas the pyrethroids beta-cyfluthrin, etofenprox and permethrin caused mortality between 8.5% and 46.25%. At the moment of application, all the insecticides were highly toxic to the wasps, causing mortality higher than 80%. In the absence of rain, all the insecticides continued to cause high mortality to the wasps for 30 days after the application. The toxicity of spinosad and methamidophos on both wasp species; beta-cyfluthrin on P. sylveirae and chlorfenapyr and abamectin on P. scutellaris, decreased when the plants received 4 mm of rain. In contrast, the other insecticides only showed reduced toxicity on the wasps when the plants received 125 mm of rain.

  1. Development of a pixelated CdTe detector module for a hard-x and gamma-ray imaging spectrometer application

    NASA Astrophysics Data System (ADS)

    Galvèz, J.-L.; Hernanz, M.; Álvarez, L.; Artigues, B.; Álvarez, J.-M.; Ullán, M.; Lozano, M.; Pellegrini, G.; Cabruja, E.; Martínez, R.; Chmeissani, M.; Puigdengoles, C.

    2016-07-01

    Stellar explosions are relevant and interesting astrophysical phenomena. Since long ago we have been working on the characterization of novae and supernovae in X and gamma-rays, with the use of space missions. We have also been involved in feasibility studies of future instruments in the energy range from several keV up to a few MeV, in collaboration with other research institutes. High sensitivities are essential to perform detailed studies of cosmic explosions and cosmic accelerators, e.g., Supernovae and Classical Novae. In order to fulfil the combined requirement of high detection efficiency with good spatial and energy resolution, an initial module prototype based on CdTe pixel detectors is being developed. The detector dimensions are 12.5mm x 12.5mm x 2mm with a pixel pitch of 1mm x 1mm. Two kinds of CdTe pixel detectors with different contacts have been tested: ohmic and Schottky. Each pixel is bump bonded to a fanout board made of Sapphire substrate and routed to the corresponding input channel of the readout VATAGP7.1 ASIC, to measure pixel position and pulse height for each incident gamma-ray photon. The study is complemented by the simulation of the CdTe module performance using the GEANT 4 and MEGALIB tools, which will help us to optimise the detector design. We will report on the spectroscopy characterisation of the CdTe detector module as well as the study of charge sharing.

  2. Thin Single Crystal Silicon Solar Cells on Ceramic Substrates: November 2009 - November 2010

    SciTech Connect

    Kumar, A.; Ravi, K. V.

    2011-06-01

    In this program we have been developing a technology for fabricating thin (< 50 micrometres) single crystal silicon wafers on foreign substrates. We reverse the conventional approach of depositing or forming silicon on foreign substrates by depositing or forming thick (200 to 400 micrometres) ceramic materials on high quality single crystal silicon films ~ 50 micrometres thick. Our key innovation is the fabrication of thin, refractory, and self-adhering 'handling layers or substrates' on thin epitaxial silicon films in-situ, from powder precursors obtained from low cost raw materials. This 'handling layer' has sufficient strength for device and module processing and fabrication. Successful production of full sized (125 mm X 125 mm) silicon on ceramic wafers with 50 micrometre thick single crystal silicon has been achieved and device process flow developed for solar cell fabrication. Impurity transfer from the ceramic to the silicon during the elevated temperature consolidation process has resulted in very low minority carrier lifetimes and resulting low cell efficiencies. Detailed analysis of minority carrier lifetime, metals analysis and device characterization have been done. A full sized solar cell efficiency of 8% has been demonstrated.

  3. Skeletal muscle injury induced by a pneumatic tourniquet: an enzyme- and immunohistochemical study in rabbits.

    PubMed

    Pedowitz, R A; Fridén, J; Thornell, L E

    1992-03-01

    The pathophysiology of skeletal muscle injury induced by compression beneath pneumatic tourniquets is poorly understood. Tourniquet hemostasis was induced in rabbit hindlimbs for 2 hr with a cuff inflation pressure of either 125 mm Hg (n = 5) or 350 mm Hg (n = 5). Skeletal muscle biopsies, taken 2 days later from tissue beneath and distal to the tourniquet, were frozen and analyzed using enzyme- and immunohistochemical techniques. In the 350 mm Hg tourniquet group, four of 10 thigh muscle samples demonstrated significant regional necrosis (mean 37.3% of the total cross-sectional area). Regional necrosis was not observed in thigh muscles of the 125 mm Hg tourniquet group or in any of the ischemic leg muscles. A topographic pattern of necrosis consistent with the arterial distribution of skeletal muscle suggested pathogenic events during the reperfusion period, such as granulocyte-mediated superoxide radical formation. Extremely large and rounded fibers (histochemically identified as Type IIB fibers) were observed in compressed thigh muscles, indicating differential fiber sensitivity to tourniquet compression and ischemia. The present study demonstrated significant skeletal muscle necrosis after a 2 hr tourniquet applied at a clinically relevant cuff inflation pressure. Recent studies of systemic changes associated with limb "ischemia" should be reassessed in consideration of the confounding effects of tissue compression induced beneath pneumatic tourniquets.

  4. Fabrication of nano-sized magnetic tunnel junctions using lift-off process assisted by atomic force probe tip.

    PubMed

    Jung, Ku Youl; Min, Byoung-Chul; Ahn, Chiyui; Choi, Gyung-Min; Shin, Il-Jae; Park, Seung-Young; Rhie, Kungwon; Shin, Kyung-Ho

    2013-09-01

    We present a fabrication method for nano-scale magnetic tunnel junctions (MTJs), employing e-beam lithography and lift-off process assisted by the probe tip of atomic force microscope (AFM). It is challenging to fabricate nano-sized MTJs on small substrates because it is difficult to use chemical mechanical planarization (CMP) process. The AFM-assisted lift-off process enables us to fabricate nano-sized MTJs on small substrates (12.5 mm x 12.5 mm) without CMP process. The e-beam patterning has been done using bi-layer resist, the poly methyl methacrylate (PMMA)/ hydrogen silsesquioxane (HSQ). The PMMA/HSQ resist patterns are used for both the etch mask for ion milling and the self-aligned mask for top contact formation after passivation. The self-aligned mask buried inside a passivation oxide layer, is readily lifted-off by the force exerted by the probe tip. The nano-MTJs (160 nm x 90 nm) fabricated by this method show clear current-induced magnetization switching with a reasonable TMR and critical switching current density.

  5. Variation of quantitative emphysema measurements from CT scans

    NASA Astrophysics Data System (ADS)

    Keller, Brad M.; Reeves, Anthony P.; Henschke, Claudia I.; Barr, R. Graham; Yankelevitz, David F.

    2008-03-01

    Emphysema is a lung disease characterized by destruction of the alveolar air sacs and is associated with long-term respiratory dysfunction. CT scans allow for imaging of the anatomical basis of emphysema, and several measures have been introduced for the quantification of the extent of disease. In this paper we compare these measures for repeatability over time. The measures of interest in this study are emphysema index, mean lung density, histogram percentile, and the fractal dimension. To allow for direct comparisons, the measures were normalized to a 0-100 scale. These measures have been computed for a set of 2,027 scan pairs in which the mean interval between scans was 1.15 years (σ: 93 days). These independent pairs were considered with respect to three different scanning conditions (a) 223 pairs where both were scanned with a 5 mm slice thickness protocol, (b) 695 with the first scanned with the 5 mm protocol and the second with a 1.25 mm protocol, and (c) 1109 pairs scanned both times using a 1.25 mm protocol. We found that average normalized emphysema index and histogram percentiles scores increased by 5.9 and 11 points respectively, while the fractal dimension showed stability with a mean difference of 1.2. We also found, a 7 point bias introduced for emphysema index under condition (b), and that the fractal dimension measure is least affected by scanner parameter changes.

  6. [Influence of adhesion on the color of glass infiltrated alumina ceramic restorations].

    PubMed

    Jiang, Li; Yang, Liu; Xu, Qiang; Guan, Hong-Yu; Wan, Qian-Bing

    2006-10-01

    To investigate the effects of luting agent on the final color of glass infiltrated alumina ceramic restorations. 12 plate-shaped specimens with 12.5 mm in diameter and 0.5 mm thickness were fabricated from GI-II (color IG2). Vitadur alpha veneering porcelain (color A2) with 1.0 mm thickness was fired to GI- II glass/alumina composite. 12 plate-shaped background specimens simulating the metal alloy post-and-core 12.5 mm in diameter and 2 mm thickness were also made from Ni-Cr alloy. All-ceramic specimens were luted to the metal alloy by Zinc Phosphate cement, glass ionomer cement and composite resin. The color shifts of the specimens were measured by colorimeter. Luting agents had effect on the final color of restorations. The influence of composite resin was least, followed by glass ionomer cement and Zinc Phosphate cement. The color difference between with and without Zinc Phosphate cement could be identified by the eye. To reduce the effect of luting agents, composite resin is recommended to all-ceramic restorations' adhesion.

  7. Optimization of selective emitter fabrication method for solar cells using a laser grooving.

    PubMed

    Jung, W W; Kim, S C; Jung, S W; Moon, I Y; Kumar, K; Lee, Y W; Kim, S Y; Ju, M K; Han, S K; Yi, J

    2011-05-01

    In this paper, screen-printing laser grooved buried contact (LGBC) method was applied, which is compatible with the existing screen-printed solar cell equipment and facilities. Experiments were performed in order to optimize short circuit current (I(sc)), open circuit voltage (V(oc)) and fill factor of high efficiency solar cells. To enhance I(sc), V(oc) and efficiency, heavy doping was performed at low sheet resistance in the laser grooved region of the cell. In contrast, light doping was carried out at a high sheet resistance in the non-laser grooved region. To increase fill factor, porous silicon found on the wafer after dipping in an HF solution to remove SiN(x), was cleared. The fabricated screen-printing LGBC solar cell using a 125 mm x 125 mm single crystalline silicon wafer exhibited an efficiency of 17.2%. The results show that screen-printing LGBC method can be applied for high efficiency solar cells.

  8. SU-E-P-11: Comparison of Image Quality and Radiation Dose Between Different Scanner System in Routine Abdomen CT

    SciTech Connect

    Liao, S; Wang, Y; Weng, H

    2015-06-15

    Purpose To evaluate image quality and radiation dose of routine abdomen computed tomography exam with the automatic current modulation technique (ATCM) performed in two different brand 64-slice CT scanners in our site. Materials and Methods A retrospective review of routine abdomen CT exam performed with two scanners; scanner A and scanner B in our site. To calculate standard deviation of the portal hepatic level with a region of interest of 12.5 mm x 12.5mm represented to the image noise. The radiation dose was obtained from CT DICOM image information. Using Computed tomography dose index volume (CTDIv) to represented CT radiation dose. The patient data in this study were with normal weight (about 65–75 Kg). Results The standard deviation of Scanner A was smaller than scanner B, the scanner A might with better image quality than scanner B. On the other hand, the radiation dose of scanner A was higher than scanner B(about higher 50–60%) with ATCM. Both of them, the radiation dose was under diagnostic reference level. Conclusion The ATCM systems in modern CT scanners can contribute a significant reduction in radiation dose to the patient. But the reduction by ATCM systems from different CT scanner manufacturers has slightly variation. Whatever CT scanner we use, it is necessary to find the acceptable threshold of image quality with the minimum possible radiation exposure to the patient in agreement with the ALARA principle.

  9. Separation and recovery of fine particles from waste circuit boards using an inflatable tapered diameter separation bed.

    PubMed

    Duan, Chenlong; Sheng, Cheng; Wu, Lingling; Zhao, Yuemin; He, Jinfeng; Zhou, Enhui

    2014-01-01

    Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (-0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed's fluid flow field. For 0.5-0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25-0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (-0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution.

  10. Measuring lifting forces in rock climbing: effect of hold size and fingertip structure.

    PubMed

    Bourne, Roger; Halaki, Mark; Vanwanseele, Benedicte; Clarke, Jillian

    2011-02-01

    This study investigates the hypothesis that shallow edge lifting force in high-level rock climbers is more strongly related to fingertip soft tissue anatomy than to absolute strength or strength to body mass ratio. Fifteen experienced climbers performed repeated maximal single hand lifting exercises on rectangular sandstone edges of depth 2.8, 4.3, 5.8, 7.3, and 12.5 mm while standing on a force measurement platform. Fingertip soft tissue dimensions were assessed by ultrasound imaging. Shallow edge (2.8 and 4.3 mm) lifting force, in newtons or body mass normalized, was uncorrelated with deep edge (12.5 mm) lifting force (r < .1). There was a positive correlation (r = .65, p < .05) between lifting force in newtons at 2.8 mm edge depth and tip of bone to tip of finger pulp measurement (r < .37 at other edge depths). The results confirm the common perception that maximum lifting force on a deep edge ("strength") does not predict maximum force production on very shallow edges. It is suggested that increased fingertip pulp dimension or plasticity may enable increased deformation of the fingertip, increasing the skin to rock contact area on very shallow edges, and thus increase the limit of force production. The study also confirmed previous assumptions of left/right force symmetry in climbers.

  11. Influence of different base thicknesses on maxillary complete denture processing: linear and angular graphic analysis on the movement of artificial teeth.

    PubMed

    Mazaro, José Vitor Quinelli; Gennari Filho, Humberto; Vedovatto, Eduardo; Amoroso, Andressa Paschoal; Pellizzer, Eduardo Piza; Zavanelli, Adriana Cristina

    2011-09-01

    The purpose of this study was to compare the dental movement that occurs during the processing of maxillary complete dentures with 3 different base thicknesses, using 2 investment methods, and microwave polymerization. A sample of 42 denture models was randomly divided into 6 groups (n = 7), with base thicknesses of 1.25, 2.50, and 3.75 mm and gypsum or silicone flask investment. Points were demarcated on the distal surface of the second molars and on the back of the gypsum cast at the alveolar ridge level to allow linear and angular measurement using AutoCAD software. The data were subjected to analysis of variance with double factor, Tukey test and Fisher (post hoc). Angular analysis of the varying methods and their interactions generated a statistical difference (P = 0.023) when the magnitudes of molar inclination were compared. Tooth movement was greater for thin-based prostheses, 1.25 mm (-0.234), versus thick 3.75 mm (0.2395), with antagonistic behavior. Prosthesis investment with silicone (0.053) showed greater vertical change compared with the gypsum investment (0.032). There was a difference between the point of analysis, demonstrating that the changes were not symmetric. All groups evaluated showed change in the position of artificial teeth after processing. The complete denture with a thin base (1.25 mm) and silicone investment showed the worst results, whereas intermediate thickness (2.50 mm) was demonstrated to be ideal for the denture base.

  12. Twist knot cerclage wire: the appropriate wire tension for knot construction and fracture stability.

    PubMed

    Harnroongroj, Thossart

    1998-09-01

    OBJECTIVE: The aim was to find the best wire tension in order to permit a reliable first twist and simultaneously provide the best stability of fracture fixation from the twist knot cerclage wire. DESIGN: Wires at different distal tensions, looped around the fracture, were measured during twist and compared with the yield strength of the wire. Then, the fracture stability of the twist knot cerclage wire was determined from the pull-out strength. METHODS: In order to measure wire tension during twist knot construction, an instrument was designed using the tension load cell of a universal testing machine, a 15 degrees oblique osteotomy femoral shaft and 1.25 mm diameter wire. A wire tensioner and a pair of extraction grips were then used for measuring the pull-out strength of the cerclage wire fixation. RESULT: Three wire tensions (160, 200 and 240 N) were used as looped wire for the first twist knot construction. The 200 N tension cerclage wire provided the best fracture stability. CONCLUSION: It was found that 200 N was the best wire tension for the construction of a twist knot cerclage wire. RELEVANCE: When a cerclage wire is twisted at a femoral shaft using 1.25 mm diameter wire, a wire tension of 200 N should be used to achieve a reliable first twist and the best stability of fracture fixation.

  13. Fixation, registration, and image-guided navigation using a thermoplastic facial mask in electromagnetic navigation-guided radiofrequency thermocoagulation.

    PubMed

    Chen, Min-jie; Gu, Li-xu; Zhang, Wei-jie; Yang, Chi; Zhao, Jing; Shao, Zi-yang; Wang, Bao-li

    2010-10-01

    For fixation, registration, and image-guided navigation, the aim of this study was to evaluate a thermoplastic facial mask with plastic markers in achieving frameless stereotactic radiofrequency thermocoagulation (RFT). A thermoplastic facial mask was remolded according to each subject's face. Six markers were placed on the surface and 6 inside. Series of 1.25-mm- and 2.5-mm-slice computerized tomography (CT) scans were made to provide radiologic data. During the phantom study, each plastic sphere inside was selected in turn as the target for frameless stereotaxy. The clinical Hartel puncture of the foramen ovale (FO) was imitated using an electromagnetic navigation system. Navigation-guided RFT was tried in 3 patients. The mean location error was 1.29 mm (SD ± 0.39 mm). No significant difference (P > .05) was proven between 1.25-mm and 2.5-mm CT slice acquisition for the image datasets used. The FO punctures in clinical trials were successful and confirmed by CT. Registration and fixation via a fiducial marker-based thermoplastic facial mask is accurate and feasible for use in navigation-guided RFT. Copyright © 2010 Mosby, Inc. All rights reserved.

  14. Multi-detector row CT colonography: effect of collimation, pitch, and orientation on polyp detection in a human colectomy specimen.

    PubMed

    Taylor, Stuart A; Halligan, Steve; Bartram, Clive I; Morgan, Paul R; Talbot, Ian C; Fry, Nicola; Saunders, Brian P; Khosraviani, Kirosh; Atkin, Wendy

    2003-10-01

    To investigate the effects of orientation, collimation, pitch, and tube current setting on polyp detection at multi-detector row computed tomographic (CT) colonography and to determine the optimal combination of scanning parameters for screening. A colectomy specimen containing 117 polyps of different sizes was insufflated and imaged with a multi-detector row CT scanner at various collimation (1.25 and 2.5 mm), pitch (3 and 6), and tube current (50, 100, and 150 mA) settings. Two-dimensional multiplanar reformatted images and three-dimensional endoluminal surface renderings from the 12 resultant data sets were examined by one observer for the presence and conspicuity of polyps. The results were analyzed with Poisson regression and logistic regression to determine the effects of scanning parameters and of specimen orientation on polyp detection. The percentage of polyps that were detected significantly increased when collimation (P =.008) and table feed (P =.03) were decreased. Increased tube current resulted in improved detection only of polyps with a diameter of less than 5 mm. Polyps of less than 5 mm were optimally depicted with a collimation of 1.25 mm, a pitch of 3, and a tube current setting of 150 mA; polyps with a diameter greater than 5 mm were adequately depicted with 1.25-mm collimation and with either pitch setting and any of the three tube current settings. Small polyps in the transverse segment (positioned at a 90 degrees angle to the z axis of scanning) were significantly less visible than those in parallel or oblique orientations (P <.001). The effective radiation dose, calculated with a Monte Carlo simulation, was 1.4-10.0 mSv. Detection of small polyps (<5 mm) with multi-detector row CT is highly dependent on collimation, pitch, and, to a lesser extent, tube current. Collimation of 1.25 mm, combined with pitch of 6 and tube current of 50 mA, provides for reliable detection of polyps 5 mm or larger while limiting the effective radiation dose. Polyps smaller than 5 mm, however, may be poorly depicted with use of these settings in the transverse colon. Copyright RSNA, 2003

  15. How do kV and mAs affect CT lesion detection performance?

    NASA Astrophysics Data System (ADS)

    Huda, W.; Ogden, K. M.; Shah, K.; Jadoo, C.; Scalzetti, E. M.; Lavallee, R. L.; Roskopf, M. L.

    2007-03-01

    The purpose of this study was to investigate how output (mAs) and x-ray tube voltage (kV) affect lesion detection in CT imaging. An adult Rando phantom was scanned on a GE LightSpeed CT scanner at x-ray tube voltages from 80 to 140 kV, and outputs from 90 to 360 mAs. Axial images of the abdomen were reconstructed and viewed on a high quality monitor at a soft tissue display setting. We measured detection of 2.5 to 12.5 mm sized lesions using a 2 Alternate Forced Choice (2-AFC) experimental paradigm that determined lesion contrast (I) corresponding to a 92% accuracy (I 92%) of lesion detection. Plots of log(I 92%) versus log(lesion size) were all approximately linear. The slope of the contrast detail curve was ~ -1.0 at 90 mAs, close to the value predicted by the Rose model, but monotonically decreased with increasing mAs to a value of ~ -0.7 at 360 mAs. Increasing the x-ray tube output by a factor of four improved lesion detection by a factor of 1.9 for the smallest lesion (2.5 mm), close to the value predicted by the Rose model, but only by a factor of 1.2 for largest lesion (12.5 mm). Increasing the kV monotonically decreased the contrast detail slopes from -1.02 at 80 kV to -0.71 at 140 kV. Increasing the x-ray tube voltage from 80 to 140 kV improved lesion detection by a factor of 2.8 for the smallest lesion (2.5 mm), but only by a factor of 1.7 for largest lesion (12.5 mm). We conclude that: (i) quantum mottle is an important factor for low contrast lesion detection in images of anthropomorphic phantoms; (ii) x-ray tube voltage has a much greater influence on lesion detection performance than x-ray tube output; (iii) the Rose model only predicts CT lesion detection performance at low x-ray tube outputs (90 mAs) and for small lesions (2.5 mm).

  16. Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding.

    PubMed

    Akbar-Khanzadeh, Farhang; Milz, Sheryl A; Wagner, Cynthia D; Bisesi, Michael S; Ames, April L; Khuder, Sadik; Susi, Pam; Akbar-Khanzadeh, Mahboubeh

    2010-12-01

    Concrete grinding exposes workers to unacceptable levels of crystalline silica dust, known to cause diseases such as silicosis and possibly lung cancer. This study examined the influence of major factors of exposure and effectiveness of existing dust control methods by simulating field concrete grinding in an enclosed workplace laboratory. Air was monitored during 201 concrete grinding sessions while using a variety of grinders, accessories, and existing dust control methods, including general ventilation (GV), local exhaust ventilation (LEV), and wet grinding. Task-specific geometric mean (GM) of respirable crystalline silica dust concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled-grinding, while GV was off/on, were 0.17/0.09, 0.57/0.13, 1.11/0.44, and 23.1/6.80, respectively. Silica dust concentrations (mg/m³ using 100-125 mm (4-5 inch) and 180 mm (7 inch) grinding cups were 0.53/0.22 and 2.43/0.56, respectively. GM concentrations of silica dust were significantly lower for (1) GV on (66.0%) vs. off, and (2) LEV:HEPA- (99.0%), LEV:Shop-vac- (98.1%) or wet- (94.4%) vs. uncontrolled-grinding. Task-specific GM of respirable suspended particulate matter (RSP) concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled grinding, while GV was off/on, were 1.58/0.63, 7.20/1.15, 9.52/4.13, and 152/47.8, respectively. GM concentrations of RSP using 100-125 mm and 180 mm grinding cups were 4.78/1.62 and 22.2/5.06, respectively. GM concentrations of RSP were significantly lower for (1) GV on (70.2%) vs. off, and (2) LEV:HEPA- (98.9%), LEV:Shop-vac- (96.9%) or wet- (92.6%) vs. uncontrolled grinding. Silica dust and RSP were not significantly affected by (1) orientation of grinding surfaces (vertical vs. inclined); (2) water flow rates for wet grinding; (3) length of task-specific sampling time; or, (4) among cup sizes of 100, 115 or 125 mm. No combination of factors or control methods reduced an 8-hr exposure level to below the

  17. Uncoupling of the baroreflex by N(N)-cholinergic blockade in dissecting the components of cardiovascular regulation

    NASA Technical Reports Server (NTRS)

    Shannon, J. R.; Jordan, J.; Black, B. K.; Costa, F.; Robertson, D.

    1998-01-01

    Systemic administration of adrenergic agonists and nitric oxide donors is used extensively to determine cardiovascular receptor sensitivity. Conclusions regarding receptor sensitivity in the presence of the baroreflex may be misleading. In 8 normal volunteers, we determined the heart rate and blood pressure changes after incremental bolus doses of isoproterenol, phenylephrine, and sodium nitroprusside before and during neuronal nicotinic cholinergic (N(N)-cholinergic) blockade with trimethaphan. Results are given as median (25th/75th percentile). With trimethaphan, the baroreflex slope (as determined by bolus doses of nitroprusside and phenylephrine) decreased from 24 (22/26) to 0.00 (0.00/0.09) ms/mm Hg (P<0.01). The dose of isoproterenol that decreased systolic blood pressure (SBP) 12.5 mm Hg changed from 0.61 (0.51/5.3) to 0.17 (0.12/0.21) microg (P<0.01); the dose required to increase heart rate 12.5 bpm changed from 0.22 (0.17/0.41) to 0.74 (0.33/2.3) microg (P<0.01). The dose of nitroprusside required to decrease SBP 12.5 mm Hg changed from 2.3 (1.3/3.4) to 0.18 (0.14/0.24) microg/kg (P<0.01). The dose of phenylephrine required to increase SBP 12.5 mm Hg changed from 135 (110/200) to 16 (10/30) microg (P<0.01). We conclude that the efferent arc of the baroreflex can be completely interrupted with N(N)-cholinergic blockade. Estimation of adrenoreceptor sensitivity and sensitivity to nitric oxide donors by systemic administration of agonists is severely confounded by baroreflexes. Uncoupling of the baroreflex by N(N)-cholinergic blockade may be a useful method to obtain an integrated measure of adrenergic receptor sensitivity and sensitivity to nitric oxide donors in humans. This approach would permit the comparison of normal and abnormal physiological states without the "noise" of baroreflex buffering.

  18. SU-C-210-04: Considerable Pancreatic Tumor Motion During Breath-Hold Measured Using Intratumoral Fiducials On Fluoroscopic Movies

    SciTech Connect

    Lens, E; Horst, A van der; Versteijne, E; Tienhoven, G van; Bel, A

    2015-06-15

    Purpose: Using a breath hold (BH) technique during radiotherapy of pancreatic tumors is expected to reduce intra-fractional motion. The aim of this study was to evaluate the tumor motion during BH. Methods: In this pilot study, we included 8 consecutive pancreatic cancer patients. All had 2– 4 intratumoral gold fiducials. Patients were asked to perform 3 consecutive 30-second end-inhale BHs on day 5, 10 and 15 of their three-week treatment. During BH, airflow through a mouthpiece was measured using a spirometer. Any inadvertent flow of air during BH was monitored for all patients. We measured tumor motion on lateral fluoroscopic movies (57 in total) made during BH. In each movie the fiducials as a group were tracked over time in superior-inferior (SI) and anterior-posterior (AP) direction using 2-D image correlation between consecutive frames. We determined for each patient the range of intra-BH motion over all movies; we also determined the absolute means and standard deviations (SDs) for the entire patient group. Additionally, we investigated the relation between inadvertent airflow during BH and the intra-BH motion. Results: We found intra-BH tumor motion of up to 12.5 mm (range, 1.0–12.5 mm) in SI direction and up to 8.0 mm (range, 1.0–8.0 mm) in AP direction. The absolute mean motion over the patient population was 4.7 (SD: 3.0) mm and 2.8 (SD: 1.2) mm in the SI and AP direction, respectively. Patients were able to perform stable consecutive BHs; during only 20% of the movies we found very small airflows (≤ 65 ml). These were mostly stepwise in nature and could not explain the continuous tumor motions we observed. Conclusion: We found substantial (up to 12.5 mm) pancreatic tumor motion during BHs. We found minimal inadvertent airflow, seen only during a minority of BHs, and this did not explain the obtained results. This work was supported by the foundation Bergh in het Zadel through the Dutch Cancer Society (KWF Kankerbestrijding) project No. UVA 2011-5271.

  19. Uncoupling of the baroreflex by N(N)-cholinergic blockade in dissecting the components of cardiovascular regulation

    NASA Technical Reports Server (NTRS)

    Shannon, J. R.; Jordan, J.; Black, B. K.; Costa, F.; Robertson, D.

    1998-01-01

    Systemic administration of adrenergic agonists and nitric oxide donors is used extensively to determine cardiovascular receptor sensitivity. Conclusions regarding receptor sensitivity in the presence of the baroreflex may be misleading. In 8 normal volunteers, we determined the heart rate and blood pressure changes after incremental bolus doses of isoproterenol, phenylephrine, and sodium nitroprusside before and during neuronal nicotinic cholinergic (N(N)-cholinergic) blockade with trimethaphan. Results are given as median (25th/75th percentile). With trimethaphan, the baroreflex slope (as determined by bolus doses of nitroprusside and phenylephrine) decreased from 24 (22/26) to 0.00 (0.00/0.09) ms/mm Hg (P<0.01). The dose of isoproterenol that decreased systolic blood pressure (SBP) 12.5 mm Hg changed from 0.61 (0.51/5.3) to 0.17 (0.12/0.21) microg (P<0.01); the dose required to increase heart rate 12.5 bpm changed from 0.22 (0.17/0.41) to 0.74 (0.33/2.3) microg (P<0.01). The dose of nitroprusside required to decrease SBP 12.5 mm Hg changed from 2.3 (1.3/3.4) to 0.18 (0.14/0.24) microg/kg (P<0.01). The dose of phenylephrine required to increase SBP 12.5 mm Hg changed from 135 (110/200) to 16 (10/30) microg (P<0.01). We conclude that the efferent arc of the baroreflex can be completely interrupted with N(N)-cholinergic blockade. Estimation of adrenoreceptor sensitivity and sensitivity to nitric oxide donors by systemic administration of agonists is severely confounded by baroreflexes. Uncoupling of the baroreflex by N(N)-cholinergic blockade may be a useful method to obtain an integrated measure of adrenergic receptor sensitivity and sensitivity to nitric oxide donors in humans. This approach would permit the comparison of normal and abnormal physiological states without the "noise" of baroreflex buffering.

  20. Thin-section CT of lung without ECG gating: 64-detector row CT can markedly reduce cardiac motion artifact which can simulate lung lesions.

    PubMed

    Yanagawa, Masahiro; Tomiyama, Noriyuki; Sumikawa, Hiromitsu; Inoue, Atsuo; Daimon, Tadahisa; Honda, Osamu; Mihara, Naoki; Johkoh, Takeshi; Nakamura, Hironobu

    2009-01-01

    Motion artifacts, which can mimic thickened bronchial wall and the cystic appearance of bronchiectasis, constitute a potential pitfall in the diagnosis of interstitial or bronchial disease. Therefore, purpose of our study was to evaluate whether 64-detector row CT (64-MDCT) enables a reduction in respiratory or cardiac motion artifacts in the lung area on thin-section CT without ECG gating, and to examine the correlation between cardiac motion artifact and heart rate. Thirty-two patients with suspected diffuse lung disease, who underwent both 8- and 64-MDCT (gantry rotation time, 0.5 and 0.4s, respectively), were included. The heart rates of an additional 155 patients were measured (range, 48-126 beats per minute; mean, 76 beats per minute) immediately prior to 64-MDCT, and compared to the degree of cardiac motion artifact. Two independent observers evaluated the following artifacts on a monitor without the knowledge of relevant clinical information: (1) artifacts on 8- and 64-MDCT images with 1.25-mm thickness and those on 64-MDCT images with 0.625-mm thickness in 32 patients; and (2) artifacts on 64-MDCT images with 0.625-mm thickness in 155 patients. Interobserver agreement was good in evaluating artifacts on 8-MDCT images with 1.25-mm thickness (weighted Kappa test, kappa=0.61-0.71), and fair or poor in the other evaluations (kappa<0.31). Two observers stated that cardiac motion artifacts were more significant on 8-MDCT than on 64-MDCT in all 32 patients. Statistically significant differences were found at various checkpoints only in comparing artifacts between 8- and 64-MDCT for 1.25-mm thickness (Wilcoxon's signed-rank test, p<0.0017). Cardiac motion artifacts on 64-MDCT had no significant correlation with heart rate (Spearman's correlation coefficient by rank test). The high temporal resolution of 64-MDCT appears to reduce cardiac motion artifact that can affect thin-section scans of the lung parenchyma.

  1. The use of a 3-dimensional computed tomography bone database to evaluate the risk of distal contact between the rasp tip and the endosteal cortical bone.

    PubMed

    Connor, Emmalynn; Cowie, Jonathan G; Wuestemann, Thies; Howell, Jonathan R; Whitehouse, Sarah L; Crawford, Ross W

    2016-12-01

    To use a 3-dimensional computed tomography (CT) bone database to evaluate the risk of distal contact between the rasp tip and the endosteal cortical bone. Using a 3-dimensional CT bone database, the rasps for Exeter stems of 125 mm in length and body size 1, with a femoral offset of 37.5, 44, or 50 mm were compared with those for Exeter stems of 150 mm in length and same body size with the corresponding femoral offset. Rasp geometry was determined using an engineering drawing software. Of the 631 femurs in the database, 238 (187 Caucasian and 51 Asian) were of appropriate femoral offset and proximal body size to receive a stem with an offset of 37.5, 44, or 50 mm. Of these, 145 (115 Caucasian and 30 Asian) femurs were of champagne-flute type; the prevalence was comparable between the 2 populations (61% vs. 59%, p=0.729). When using the 150-mm rasp, 70 (55 Caucasian and 15 Asian) of the 238 femurs had distal contact between the rasp and femoral cortex; the prevalence was comparable between the 2 populations (29% vs. 29%, relative risk=1.0, p=1.0). Distal contact between the rasp and femoral cortex occurred more commonly in champagne-flute-type femurs than other femurs in the anteroposterior plane (28% [41/145] vs. 2% [2/93], relative risk=13.1, p<0.001) and in the mediolateral plane (27% [39/145] vs. 14% [13/93], relative risk=1.92, p=0.019). When using the 125-mm rasp, only one femur (with a canal flare index of 4.52) had distal contact in the mediolateral plane with an offset of 37.5 mm. Distal contact between the rasp and femoral cortex occurred more often with the 150-mm rasp than the 125-mm rasp in both planes (p<0.001). The use of a shorter stem may enhance anatomic fit in patients with a narrow femoral canal and prevent distal contact between the rasp and femoral cortex.

  2. [Diol column as stationary phase for high performance liquid chromatographic analysis of carbohydrates in drinks with evaporative light scattering detection].

    PubMed

    Wei, Y; Guo, L; Ding, M Y

    2001-11-01

    A high performance liquid chromatographic method with a diol column and evaporative light scattering detector (ELSD) was established for the direct analysis of fructose, glucose, sucrose, maltose and raffinose in mixture. A separation column (Lichrospher 100 Diol, 250 mm x 4.0 mm i.d., 5 microns, Hewlett-Packard, USA) and a guard column (Zorbax Rx-SIL, 12.5 mm x 4.6 mm i.d., 5 microns) were used. The mobile phase was a mixture of dichloromethane-methanol (3.2:1, volume ratio). Regression equations revealed linear relationship (correlation coefficients: 0.995-0.999) between the mass of carbohydrates injected and the peak area of carbohydrates detected by ELSD. The detection limits of ELSD (S/N = 3) were about 0.20 microgram for all carbohydrates. This system could be used for the routine analysis of simple carbohydrates in some common drinks on market.

  3. Analysis of carbohydrates in drinks by high-performance liquid chromatography with a dynamically modified amino column and evaporative light scattering detection.

    PubMed

    Wei, Y; Ding, M Y

    2000-12-22

    A high-performance liquid chromatographic method with a dynamically modified amino column and evaporative light-scattering detector (ELSD) was established for the direct analysis of the carbohydrates in some drinks. A separation column (Zorbax Rx-SIL, 250 mm x 4.6 mm I.D., 5 microm, Hewlett-Packard, USA) which was modified by ethylenediamine and a guard column (Zorbax Rx-SIL, 12.5 mm x 4.6 mm I.D., 5 microm) were used. The mobile phase was a mixture of water-acetonitrile (1:2.6, v/v) containing 0.03% (v/v) ethylenediamine. Regression equations revealed linear relationship (correlation coefficients=0.996-0.999) between the mass of carbohydrates injected and the carbohydrates peak areas detected by ELSD. The detection limits of ELSD (S/N=3) were between 0.2 and 1.2 microg for different carbohydrates. This method is simple and sensitive.

  4. [Analysis of trehalose in transgenic tobacco extracts by high performance liquid chromatography with evaporative light scattering detection].

    PubMed

    Wei, Y; Ding, M Y

    2001-05-01

    A high performance liquid chromatographic method with ethylenediamine dynamically modified silica column and evaporative light-scattering detection (ELSD) was developed for the direct determination of trehalose in transgenic tobacco extracts. The separation column (Zorbax Rx-SIL, 4.6 mm i.d. x 250 mm, 5 microns, Hewlett-Packard, USA) modified by ethylenediamine and a guard column (Zorbax Rx-SIL, 4.6 mm i.d. x 12.5 mm, 5 microns) were used. The mobile phase was a mixture of acetonitrile-water(2.6:1, V/V) containing 0.03% ethylenediamine. Regression equations revealed the linear relationships (r = 0.996-0.999) between the concentrations and peak areas of carbohydrates detected by ELSD. The detection limits of ELSD (S/N = 3:1) were 10 mg/L, 20 mg/L, 10 mg/L and 10 mg/L for fructose, glucose, sucrose and trehalose, respectively.

  5. Characterization of transparent conductive oxide films and their effect on amorphous/crystalline silicon heterojunction solar cells

    NASA Astrophysics Data System (ADS)

    Meng, Fanying; Shi, Jianhua; Shen, Leilei; Zhang, Liping; Liu, Jinning; Liu, Yucheng; Yu, Jian; Bao, Jian; Liu, Zhengxin

    2017-04-01

    Three different dopant indium oxide thin films were fabricated at low temperatures by reactive plasma deposition and sputtering. The optical and electrical characteristics of these films were analyzed as a function of the Hall electron concentration. Furthermore, these films were applied to amorphous/crystalline silicon heterojunction solar cells as transparent electrodes. Consequently, it was demonstrated that the high Hall mobility, high refractive index, and low extinction coefficient of transparent conductive oxide (TCO) films contribute to the high product of short-circuit current density and fill factor and conversion efficiency. Furthermore, it was found that the solar cell with a finger spacing of 1.9 mm on a 125 × 125 mm2 Si wafer is highly tolerant to TCO film resistivity when the electron concentration is less than 4.0 × 1020 cm-3.

  6. Pressurized subsampling system for pressured gas-hydrate-bearing sediment: Microscale imaging using X-ray computed tomography

    SciTech Connect

    Jin, Yusuke Konno, Yoshihiro; Nagao, Jiro

    2014-09-01

    A pressurized subsampling system was developed for pressured gas hydrate (GH)-bearing sediments, which have been stored under pressure. The system subsamples small amounts of GH sediments from cores (approximately 50 mm in diameter and 300 mm in height) without pressure release to atmospheric conditions. The maximum size of the subsamples is 12.5 mm in diameter and 20 mm in height. Moreover, our system transfers the subsample into a pressure vessel, and seals the pressure vessel by screwing in a plug under hydraulic pressure conditions. In this study, we demonstrated pressurized subsampling from artificial xenon-hydrate sediments and nondestructive microscale imaging of the subsample, using a microfocus X-ray computed tomography (CT) system. In addition, we estimated porosity and hydrate saturation from two-dimensional X-ray CT images of the subsamples.

  7. Distributed Non-evaporable Getter pumps for the storage ring of the APS

    SciTech Connect

    Dortwegt, R.; Benaroya, R.

    1993-07-01

    A pair of distributed Non-evaporable Getter (NeG) strip assemblies is installed in each of 236 aluminum vacuum chambers of the 1104-m storage ring of the Advanced Photon Source. Distributed pumping is provided to remove most of the gas resulting from photon-stimulated desorption occurring along the outer walls of the chambers. This is an efficient way of pumping because conductance is limited along the beam axis. The St-707 NeG strips are conditioned at 450{degree}C for 45 min. with 42 A. Base pressures obtained are also as low as 4 {times} 10{sup 11} Torr. The NeG strip assemblies are supported by a series of electrically isolated, 125-mm-long, interlocking stainless steel carriers. These unique interlocking carrier elements provide flexibility along the vacuum chamber curvature (r=38.96 m) and permit removal and installation of assemblies with as little as 150 mm external clearance between adjacent chambers.

  8. Bend-insensitive distributed sensing in singlemode-multimode-singlemode optical fiber structure by using Brillouin optical time-domain analysis

    NASA Astrophysics Data System (ADS)

    Xu, Pengbai; Zhang, Hongying; Lu, Zhiwei; Chen, Liang; Bao, Xiaoyi; Dong, Yongkang

    2015-09-01

    We propose a bend-insensitive distributed Brillouin optical fiber sensing by using a singlemode-multimode-singlemode optical fiber structure for the first time to the best of our knowledge. The sensing fiber is a graded-index multimode fiber (GI-MMF) sandwiched by two standard single-mode fibers (SMFs) with centrally alignment splicing at the interface between GI-MMF and SMF to excite the fundamental mode only in GI-MMF. The sensing system can resist a minimal bend radius of 1.25mm while maintaining the measurement performance, with which the measured coefficient of strain is 421.6MHz/%. We also demonstrate that the higher-order modes exciting in GI-MMF can be easily influenced by bending, so that the fundamental mode exciting is essential for bend-insensitive distributed sensing.

  9. NIKEL_AMC: readout electronics for the NIKA2 experiment

    NASA Astrophysics Data System (ADS)

    Bourrion, O.; Benoit, A.; Bouly, J. L.; Bouvier, J.; Bosson, G.; Calvo, M.; Catalano, A.; Goupy, J.; Li, C.; Macías-Pérez, J. F.; Monfardini, A.; Tourres, D.; Ponchant, N.; Vescovi, C.

    2016-11-01

    The New Iram Kid Arrays-2 (NIKA2) instrument has recently been installed at the IRAM 30 m telescope. NIKA2 is a state-of-art instrument dedicated to mm-wave astronomy using microwave kinetic inductance detectors (KID) as sensors. The three arrays installed in the camera, two at 1.25 mm and one at 2.05 mm, feature a total of 3300 KIDs. To instrument these large array of detectors, a specifically designed electronics, composed of 20 readout boards and hosted in three microTCA crates, has been developed. The implemented solution and the achieved performances are presented in this paper. We find that multiplexing factors of up to 400 detectors per board can be achieved with homogeneous performance across boards in real observing conditions, and a factor of more than 3 decrease in volume with respect to previous generations.

  10. Rail accelerator technology and applications

    NASA Technical Reports Server (NTRS)

    Zana, L. M.; Kerslake, W. R.

    1985-01-01

    Rail accelerators offer a viable means of launching ton-size payloads from the Earth's surface to space. The results of two mission studies which indicate that an Earth-to-Space Rail Launcher (ESRL) system is not only technically feasible but also economically beneficial, particularly when large amounts of bulk cago are to be delivered to space are given. An in-house experimental program at the Lewis Research Center (LeRC) was conducted in parallel with the mission studies with the objective of examining technical feasibility issues. A 1 m long - 12.5 by 12.5 mm bore rail accelerator as designed with clear polycarbonate sidewalls to visually observe the plasma armature acceleration. The general character of plasma/projectile dynamics is described for a typical test firing.

  11. Pressurized subsampling system for pressured gas-hydrate-bearing sediment: microscale imaging using X-ray computed tomography.

    PubMed

    Jin, Yusuke; Konno, Yoshihiro; Nagao, Jiro

    2014-09-01

    A pressurized subsampling system was developed for pressured gas hydrate (GH)-bearing sediments, which have been stored under pressure. The system subsamples small amounts of GH sediments from cores (approximately 50 mm in diameter and 300 mm in height) without pressure release to atmospheric conditions. The maximum size of the subsamples is 12.5 mm in diameter and 20 mm in height. Moreover, our system transfers the subsample into a pressure vessel, and seals the pressure vessel by screwing in a plug under hydraulic pressure conditions. In this study, we demonstrated pressurized subsampling from artificial xenon-hydrate sediments and nondestructive microscale imaging of the subsample, using a microfocus X-ray computed tomography (CT) system. In addition, we estimated porosity and hydrate saturation from two-dimensional X-ray CT images of the subsamples.

  12. Impact verification of space suit design for space station

    NASA Technical Reports Server (NTRS)

    Fish, Richard H.

    1987-01-01

    The ballistic limits of single sheet and double sheet structures made of 6061 T6 Aluminum of 1.8 mm and larger nominal thickness were investigated for projectiles of 1.5 mm diameter fired in the Vertical Gun Range Test Facility and NASA Ames Research Center. The hole diameters and sheet deformation behavior were studied for various ratios of sheet spacing to projectile diameter. The results indicate that for projectiles of less than 1.5 mm diameter the ballistic limit exceeds the nominal 10 km/sec orbital debris encounter velocity, if a single-sheet suit of 1.8 mm thickness is behind a single bumper sheet of 1 mm thickness spaced 12.5 mm apart.

  13. Silicon concentrator solar cell development

    NASA Astrophysics Data System (ADS)

    Green, Martin A.; Jianhua, Zhao; Aihua, Wang; Blakers, A. W.

    1990-05-01

    This project involved the development and supply of 550 silicon concentrator solar cells for use in prototype point-focus concentrator modules. The cells were to have a designed illumination area of 12.5 by 12.5 mm and to be designed for use with prismatic covers at a geometric concentration ratio of 200X. The target efficiency of 24 percent was comfortably exceeded, with efficiencies as high as 25.2 percent reached in the designed concentration ratio range. A combined lens/cell efficiency of 24.4 percent was measured at Sandia using a cell supplied during this project and a point focus Fresnel lens. Subsequently, a peak module efficiency of 20.3 percent was achieved at Sandia using 12 cells and lenses. This is believed to be the first photovoltaic module to surpass the 20 percent efficiency milestone.

  14. Estudios interferométricos del campo magnético en regiones de formación estelar

    NASA Astrophysics Data System (ADS)

    Fernández López, M.; Stephens, I.; Segura-Cox, D.; Crutcher, R.; Looney, L. W.; Kwon, W.

    2015-08-01

    Currently, the possible role of magnetic fields in star formation processes is not clear. Despite the efforts made through single-dish observations, a stronger observational effort is required in order to broaden the sample of detections and acquire more insight into the morphology of the magnetic field at high-angular resolution scales. Here we present some results obtained from CARMA 1.25 mm continuum and spectral line polarization observations. The target of these observations were two accretion disks around a Class 0 (L1527) and a T Tauri (HL Tau) protostar and the massive star-forming region W3OH. We resolved the morphology of the magnetic field in both disks and, in W3OH, we achieved the first Zeeman detection ever made with an interferometer.

  15. [Anthropometric analysis of obstetrical pelvis from Neolithic area: obstetrical consequences. Preliminary study].

    PubMed

    Raia-Barjat, T; Tardieu, A-S; Amouzougan, A; Trombert, B; Chauleur, C; Varlet, M-N; Patural, H; Seffert, P; Chêne, G

    2011-11-01

    To study female pelves from Neolithic area (5000 years AD) in order to better understand the evolution of obstetrical mecanisms. The fossil material comprised 73 Homo sapiens pelves: we reconstructed all the 20 adult female bony pelves. We realised the shape and morphometric analysis of the pelvic cavity. Changes in pelvic neolithic morphology were compared with pelvic modern morphology. The pelves of prehistoric female were similar in shape with modern female. However, they differ in relative dimensions (transversal diameter of the pelvis inlet: respectively 118 mm vs 125 mm, p=0.02). Reconstructions based on Neolithic hominin fossils suggest that obstetrical mechanisms were probably common to Neolithic and modern humans: childbirth would probably require social adaptations and risks of perinatal and obstetric complications were undoubtedly high. However, the differences in morphometric analysis could suggest a change of human pelvis and raise the question of the evolution in obstetrical mechanisms in the future. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  16. Epikeratoplasty for keratoglobus associated with blue sclera.

    PubMed

    Cameron, J A; Cotter, J B; Risco, J M; Alvarez, H

    1991-04-01

    Patients with keratoglobus and blue sclera as part of a generalized connective tissue disorder are at a high risk of developing corneal perforations either spontaneously or after mild trauma. Six patients (6 eyes) between the ages of 2 and 16 years of age (mean, 7.5 years) with keratoglobus, blue sclera, hypermobile joints, and consanguineous parents were treated by epikeratoplasty, using commercially prepared 12.5-mm lenticules. Surgery was performed for tectonic support and/or visual improvement and was successful in five of six patients with a follow-up period of 11 to 27 months (mean, 21 months). One lenticule was removed because the epithelium did not heal. Peripheral interface opacities occurred in three patients.

  17. Effect of laser parameters on the microstructure of bonding porcelain layer fused on titanium

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoyuan; Guo, Litong; Liu, Xuemei; Feng, Wei; Li, Baoe; Tao, Xueyu; Qiang, Yinghuai

    2017-09-01

    Bonding porcelain layer was fused on Ti surface by laser cladding process using a 400 W pulse CO2 laser. The specimens were studied by field-emission scanning electron microscopy, X-ray diffraction and bonding tests. During the laser fusion process, the porcelain powders were heated by laser energy and melted on Ti to form a chemical bond with the substrate. When the laser scanning speed decreased, the sintering temperature and the extent of the oxidation of Ti surface increased accordingly. When the laser scanning speed is 12.5 mm/s, the bonding porcelain layers were still incomplete sintered and there were some micro-cracks in the porcelain. When the laser scanning speed decreased to 7.5 mm/s, vitrified bonding porcelain layers with few pores were synthesized on Ti.

  18. Experimental Acquisitions with ^125I on a Small Animal SPECT Device*

    NASA Astrophysics Data System (ADS)

    Knott, Kevin; Welsh, Robert E.; Bradley, Eric L.; Saha, Margaret S.; Kross, Brian; Majewski, Stan; Popov, Vladimir; Smith, Mark F.; Weisenberger, Andrew G.; Wojcik, Randolph

    2001-04-01

    We have performed single photon emission computed tomography (SPECT) studies on a small animal scanning system for which the detector employed position sensitive phototubes (125 mm dia. Hamamatsu R3292 and 18 x 18 mm Hamamatsu M-64) coupled to pixelated scintillators CsI(Tl) and CsI(Na) Phantom acquisitions were used to investigate the effects of angular sampling and scan time on reconstructed image quality and noise. Results from these studies will be described and extended to in vivo studies with small animals. *Supported in part by the Thomas F. and Kate Miller Jeffress Trust, the Department of Energy, The American Diabetes Association, The National Science Foundation, the Howard Hughes Foundation and the Virginia Commonwealth Health Research Board.

  19. Neurosurgical applications of ocular pneumoplethysmography.

    PubMed

    Bingham, W F

    1981-05-01

    Ocular pneumoplethysmography (OPG), a semiautomated form of suction ophthalmodynamometry, was used to evaluate and follow 15 patients who underwent carotid endarterectomy and two patients in whom gradual carotid artery occlusion was performed for inoperable intracranial aneurysm. Postoperative corrected ophthalmic arterial pressures (COAP's) on the operated side in the carotid endarterectomy patients averaged 12.5 mm Hg higher than before surgery, the standard deviation being 4.9 mm Hg for clinically stable patients. There was no significant change in COAP on the contralateral side. Several problems were encountered in closing down carotid clamps, the most potentially serious being a precipitous fall in COAP with the final adjustment. The current uses of OPG and similar techniques are reviewed, and potential neurosurgical applications are discussed.

  20. Two new species of Choerophryne (Anura, Microhylidae) from the northern versant of Papua New Guinea's central cordillera.

    PubMed

    Iannella, Amy; Oliver, Paul; Richards, Stephen

    2015-12-17

    We describe two new species of small microhylid frogs in the genus Choerophryne from the northern slopes of Papua New Guinea's central cordillera. Choerophryne epirrhina sp. nov. can be distinguished from congeners by the combination of moderately small size (SUL 14.9-15.0 mm), distinctly elongated snout (OHG/SUL 0.09-0.10), first finger without expanded disk, and advertisement call consisting of 3-4 distinctly pulsed notes repeated in long sequences. Choerophryne grylloides sp. nov. can be distinguished from congeners by the combination of very small size (SUL 12.5 mm), moderately long snout (OHG/SUL 0.08), long legs (TL/SUL 0.42), first finger without expanded disk and advertisement call consisting of 4-5 distinctly pulsed notes, the last of which has many more pulses than preceding notes (9-10 vs. 3-4).

  1. Multireflection pumping concept for miniaturized diode-pumped solid-state lasers.

    PubMed

    Meister, Jörg; Franzen, Rene; Apel, Christian; Gutknecht, Norbert

    2004-11-01

    An innovative pump concept for diode-pumped, solid-state lasers is introduced as an example for an Er:YSGG laser, permitting its miniaturization. Embedded in a multireflective pump cavity, the laser crystal is simultaneously side and end pumped. Specially calculated and shaped deflecting optics distribute the coaxially input pumping light homogeneously over the lateral surface of the crystal, therefore reducing the size of the laser head, including the optical resonator, to a length of 27.5 mm and an outside diameter of 12.5 mm. The differential efficiency achieved is between 8.7% and 24%. The laser emits energy of 15.7 mJ at an absolute efficiency of 9.1% and a repetition rate of 4 Hz.

  2. A new type of medical micropump for an endoscopic robot.

    PubMed

    Ye, Dongdong; Yan, Guozheng; Zan, Peng; Wang, Kundong

    2010-01-01

    Researchers have developed a new type of medical micropump for an endoscopic robot, which is driven by a linear actuator based on a direct current (DC) motor. This micropump consists of two active one-way valves and a cylindrical air drum. The overall size of the pump prototype is 12.5 mm in diameter and 56 mm in length. This paper describes the structure of the micropump and linear actuator and analyzes the inflation mechanism of the micropump. The experimental results show that the driving force of the linear actuator can reach up to 2.55 N, which fulfills the need of the micropump. The rated output flow of the micropump is 16 mL/min, which can rapidly supply the gas bag with enough air with minimal noise and vibration.

  3. Investigation of factors controlling GTA weld bead geometry

    SciTech Connect

    Smartt, H.B.; Key, J.F.

    1981-01-01

    In welding processes employing a consumable electrode, the input of heat and mass to the fusion zone is coupled. In contrast, in the gas tungsten arc welding (GTAW) process, which uses a nonconsumable tungsten electrode, the input of heat and mass to the fusion zone are not coupled. As a result, the relationships between process parameters (current, arc voltage, welding speed, and filler wire speed) and weld bead geometry (bead width, penetration, and reinforcement) for GTA welding are complex. This work presents an experimental study of the process-parameter/weld-bead-geometry relationships for constant parameter GTAW of Type 304 stainless steel. Bead-on-plate results for partial-penetration welds in 12.5-mm thick plate, using an automatic GTAW machine, are presented. Measurements of bead width, penetration, and bead transverse cross-sectional area are given for autogenous welding; measurements of bead width, penetration, reinforcement, cross-sectional area, and dilution are given for nonautogenous welding.

  4. High-Speed Laser Scanner Maps a Surface in Three Dimensions

    NASA Technical Reports Server (NTRS)

    Lavelle, Joseph; Schuet, Stefan

    2006-01-01

    A scanning optoelectronic instrument generates the digital equivalent of a threedimensional (X,Y,Z) map of a surface that spans an area with resolution on the order of 0.005 in. ( 0.125mm). Originally intended for characterizing surface flaws (e.g., pits) on space-shuttle thermal-insulation tiles, the instrument could just as well be used for similar purposes in other settings in which there are requirements to inspect the surfaces of many objects. While many commercial instruments can perform this surface-inspection function, the present instrument offers a unique combination of capabilities not available in commercial instruments. This instrument utilizes a laser triangulation method that has been described previously in NASA Tech Briefs in connection with simpler related instruments used for different purposes. The instrument includes a sensor head comprising a monochrome electronic camera and two lasers. The camera is a high-resolution

  5. Advantages of mini-multileaf in stereotactic radiotherapy

    PubMed Central

    Kurup, P. G. G.; Murali, V.; Sankar, A.

    2007-01-01

    Over the past few decades, cones of different diameter (12.5 mm to 40 mm) were used for treatment of intracranial lesions. These give very focused dose delivery to the target with minimum dose to outside normal brain tissues. This study is intended to compare the older method of arc-based stereotactic treatments using cones with the new mini-multileaf collimator (mMLC). Treatment plans are made for various sites of intracranial lesions with the cones and mMLC. In case of nonspherical lesions, more than one isocenter is used to get an optimum dose distribution with cones, while a single isocenter is sufficient with mMLC. Treatment plans are compared for irregular lesions using cones with multiple isocenters and mMLC. It is observed that conformity index and dose heterogeneity are better for mMLC based treatments. PMID:21217913

  6. Track chambers based on precision drift tubes housed inside 30 mm mylar pipe

    NASA Astrophysics Data System (ADS)

    Borisov, A.; Bozhko, N.; Fakhrutdinov, R.; Kozhin, A.; Leontiev, B.; Levin, A.

    2014-06-01

    We describe drift chambers consisting of 3 layers of 30 mm (OD) drift tubes made of double sided aluminized mylar film with thickness 0.125 mm. A single drift tube is self-supported structure withstanding 350 g tension of 50 microns sense wire located in the tube center with 10 microns precision with respect to end-plug outer surface. Such tubes allow to create drift chambers with small amount of material, construction of such chambers doesn't require hard frames. Twenty six chambers with working area from 0.8 × 1.0 to 2.5 × 2.0 m2 including 4440 tubes have been manufactured for experiments at 70-GeV proton accelerator at IHEP(Protvino).

  7. Determination of cyanocobalamin, betamethasone, and diclofenac sodium in pharmaceutical formulations, by high performance liquid chromatography.

    PubMed

    González, L; Yuln, G; Volonté, M G

    1999-07-01

    The aim of this work was to develop an analytical method for a simultaneous determination of cyanocobalamin (Vitamin B12), betamethasone, and diclofenac, present in pharmaceutical formulations, by high performance liquid chromatography, assuring rapidity, accuracy, precision, and selectivity. The working conditions were as follows: RP18 column of 125 mm x 4 mm ID and a particle size of 5 microm; mobile phase acetonitrile-water (40:60; v/v) (pH* 3.45) adjusted with acetic acidl flow gradient from 0.8 to 1.9 ml/min.; injection volume of 20 microl; temperature 34 degrees C and detection at 240 nm. The method was adequately validated, and linearity, accuracy, as well as the system, method and interday precision, for each active principle, were determined.

  8. Proceedings of Technology Showcase Held in Huntsville, Alabama on 7-9 August 1990

    DTIC Science & Technology

    1990-08-09

    provided to restrain the package and lid in the desired orientation. The pallet design also provides a constant distance , 125 mm, from the lens. Both of...development of the MACE filter is shown in Figure 3 and Figure 4. gi (n) - xi(n) ®h(n) 4 4 E" (1/N)FE I - (I1N)FHE)IH E i gi (nI. (1/d)IGi(k)I N W1 d e letting D...1X1k)I the method of Lagrange multipliers the and the correlation peak 8mlitude constraint is solution for the MACE filter Is gi (O) " X*H - u. H

  9. Nasal airflow during respiratory cycle.

    PubMed

    Chung, Seung-Kyu; Son, Young Rak; Shin, Seok Jae; Kim, Sung-Kyun

    2006-01-01

    Knowledge on the airflow patterns in the nasal cavity is essential to understanding the function of the nasal cavity. This study has attempted to observe the breath cycle of nasal airflow during respiration at rest. We constructed a nasal cavity model by rapid prototyping using 1.25-mm-thick CT data and devised a piston pump driven by a cam, to simulate respiration at rest. The airflow was evaluated with particle image velocimetry and visualized in coronal reconstructed images. During the inspiration, a maximal velocity was observed at the valve area and the main stream occurred in the middle and superior airways. During the expiration, main stream was noted in the middle airway and was slow compared with the flow during inspiration. Vortexes were observed between inspiration and expiration. This result widens our knowledge of nasal airflow and this technique will allow a more physiological understanding of nasal operations.

  10. Investigation of the efficiency process during CO2 laser welding of low-alloyed steels

    NASA Astrophysics Data System (ADS)

    Petrov, Peter; Apostolova, Tzveta

    2008-10-01

    This paper reports results from the theoretical and experimental study of the energy transfer during CO2 laser beam welding of 10 mm low-alloyed steels square butt joints. The laser beam power and the welding speed are varied systematically from 9 kW to 32 kW and from 1 m/min to 5 m/min, respectively. The observed weld depth penetration is up to 10 mm and the width of weld seams is between 0.8 and 1.25 mm. The joining efficiency during the laser welding was in the range of 11.8 to 32 mm2/kJ. Melting efficiency is determined from the measured welding seams cross section for a specified laser power and travel speed. Theoretically, predicted values of melting efficiency are calculated using Rosenthal's and Rycalin moving heat sources equation in 2D (line source).

  11. Fabrication of an ultrathin lead zirconate titanate mirror device mounted on flexible substrate

    NASA Astrophysics Data System (ADS)

    Takeshita, Toshihiro; Yamashita, Takahiro; Makimoto, Natsumi; Kobayashi, Takeshi

    2017-10-01

    We have developedultrathin MEMS mirror devices. The mirror device was driven by lead zirconate titanate (PZT) actuators. Because the thickness of the mirror device is 5.31 µm, the mirror device is flexible. The mirror device was mounted on a polyimide substrate by a mounting method that we have developed. After fabrication, we investigated the characteristics of the mirror device experimentally. The frequency of the resonant mode for scanning optical light was 10.4 kHz. Also, we conducted an experiment to confirm the flexibility of the mirror device. When the polyimide substrate was bent (radius of curvature was 125 mm), the mirror device can be actuated without breakage. Moreover, it was observed that the resonance frequency and mechanical angle of the mirror device were dependent on the radius of curvature of the flexible substrate. This fabrication and mounting technology is highly promising for the development of flexible hybrid electronic (FHE) devices.

  12. Easy mounting interface for compact instruments at TNG

    NASA Astrophysics Data System (ADS)

    Ghedina, Adriano; Riverol Rodriguez, A. Luis

    2016-08-01

    The Telescopio Nazionale Galileo (TNG) is able to offer an F/11 Nasmyth focal station with an easy mount for small devices or compact instruments. The slit masks at the focal plane of the LRS spectrograph can be removed in few minutes from the selector stage. A FoV of 9x9arcmin2 is available and a small instrument can be mounted instead of the slit on a mechanical interface of 240x125mm. The size of the instrument along the optical axis is limited by the support of the collimation lens of the spectrograph. This solution has already been used for small devices like a CCD camera or a SH sensor and a compact Hamamatsu photometer. Furthermore from 2016 it will host the folding optical relay for the GIARPS Instrument. This interface is an opportunity to test new instruments, prototypes or demonstrators in a not invasive or time consuming manner at a 4m class telescope.

  13. Fracture toughness measurements with subsize disk compact specimens

    SciTech Connect

    Alexander, D.J.

    1994-12-31

    Special fixtures and test methods have been developed for testing small disk compact specimens (1.25 mm diam by 4.6 mm thick). Specimens of European type 316L austenitic stainless steel were irradiated to damage levels of about 3 dpa at nominal irradiation temperatures of either 90 or 250 C and tested over a temperature range from 20 to 250 C. Results show that irradiation to this dose level at these temperatures reduces the fracture toughness but the toughness remains quite high. The toughness decreases as the test temperature increases. Irradiation at 250 C is more damaging than at 90 C, causing larger decreases in the fracture toughness. The testing shows that it is possible to generate useful fracture toughness data with a small disk compact specimens.

  14. [POSSIBILITIES OF VACUUM THERAPY APPLICATION IN DISORDERS OF VENOUS OUTFLOW IN ISLET GRAFTS].

    PubMed

    Badyul, P O; Samoylenko, G E; Nor, N M; Slesarenko, K S

    2015-07-01

    The experience of "distressed" (problematic) flaps application in 33 patients with soft tissue defects over 2010-2014 years were analysed. It was proposed to use the local negative pressure for the prevention and treatment of complications associated with venous insufficiency or trombosis in using of plastics with vascularised complexes of tissues. Vacuum-therapy was conducted with the help of negative pressure apparatus "AGATE-Dnepr" (Ukraine) by attaching silver-containing polyurethane sponge on the operating zone, covering the flap with the surrounding skin netting band "Grassolind". The recommended standard of negative pressure of 75-125 mm Hg, both in impulse and in continuous mode was used. The high efficiency of vacuum-therapy for survival of grafts has been demonstrated. Thus, it might be considered as an effective element of prevention and treatment of complications associated with venous insufficiency or trombosis using of vascularised tissue complex plastics of defects.

  15. Intravascular photoacoustic imaging of human coronary atherosclerosis

    NASA Astrophysics Data System (ADS)

    Jansen, Krista; van der Steen, Antonius F. W.; Springeling, Geert; van Beusekom, Heleen M. M.; Oosterhuis, J. Wolter; van Soest, Gijs

    2011-03-01

    We demonstrate intravascular photoacoustic imaging of human coronary atherosclerotic plaque. We specifically imaged lipid content, a key factor in vulnerable plaques that may lead to myocardial infarction. An integrated intravascular photoacoustics (IVPA) and ultrasound (IVUS) catheter with an outer diameter of 1.25 mm was developed. The catheter comprises an angle-polished optical fiber adjacent to a 30 MHz single-element transducer. The ultrasonic transducer was optically isolated to eliminate artifacts in the PA image. We performed measurements on a cylindrical vessel phantom and isolated point targets to demonstrate its imaging performance. Axial and lateral point spread function widths were 110 μm and 550 μm, respectively, for PA and 89 μm and 420 μm for US. We imaged two fresh human coronary arteries, showing different stages of disease, ex vivo. Specific photoacoustic imaging of lipid content, is achieved by spectroscopic imaging at different wavelengths between 1180 and 1230 nm.

  16. Investigation of the magnetic properties of Li0.8Na0.2FePO4 by using the Mössbauer spectroscopy

    NASA Astrophysics Data System (ADS)

    Ko, Byung Ug; Kouh, Taejoon; Kim, Chul Sung; Sur, Jung Chul

    2016-08-01

    We have investigated Li0.8Na0.2FePO4, a cathode material for secondary battery applications, by using X-ray diffractometry (XRD), vibrating sample magnetometry (VSM) and Mössbauer spectroscopy. The crystal structure is found to be orthorhombic with lattice parameters of a 0 = 10.333 Å, b 0 = 6.011 Å and c 0 = 4.700 Å. From the temperature dependence of both the magnetization and the Mössbauer spectra, the Néel temperature is found to be T N = 51 K and the spin reorientation temperature to be T S = 20 K. The magnetic hyperfine field ( H hf ), electric quadrupole splitting (Δ E Q ) and isomer shift ( δ) at 4.2 K are found to be H hf = 130.50 kOe, Δ E Q = 2.63 mm/s and δ = 1.25 mm/s.

  17. Low-Order, Underwater Detonation Study

    DTIC Science & Technology

    2002-04-03

    spacer and then a vaseline -filled vial were used in the 60mm water gap to try to get low-order reactions in tests MK82-8 and -9. (The foam was...Reaction MK82-7 21 7/16/01 60mm No Reaction MK82-8 21 7/16/01 60mm (Foam) Low Order MK82-9 1 7/17/01 60mm ( Vaseline ) No Reaction MK82-10 1 7/17/01 50mm No...thickness was nominally 12.5 mm). Because the shots were prepared on the surface and lowered to a depth of 24 feet, extra care was taken to ensure that

  18. Circulating bovine pregnancy associated glycoproteins are associated with late embryonic/fetal survival but not ovulatory follicle size in suckled beef cows.

    PubMed

    Pohler, K G; Geary, T W; Johnson, C L; Atkins, J A; Jinks, E M; Busch, D C; Green, J A; MacNeil, M D; Smith, M F

    2013-09-01

    The objective was to examine the relationship between ovulatory follicle size and embryo and fetal survival by using circulating concentrations of bovine pregnancy associated glycoproteins (bPAG) to detect the presence of an embryo or fetus and monitor placental function. Before examining the relationship between bPAG, ovulatory follicle size, and embryo and fetal survival, the half-life of bPAG was determined in Exp. 1. The half-life of bPAG after PGF2α-induced abortion on d 32 to 36 postinsemination was 35.8 ± 21.9 h (mean ± SD; range 7.1 to 78.5 h). In Exp. 2, suckled beef cows (n = 91) were treated with the CO-Synch protocol (GnRH on d -9, PGF2α on d -2, and GnRH and AI 48 h later [d 0]) and classified into 1 of 2 ovulatory follicle size groups: 1) small follicle (<12.5 mm; n = 25) or 2) large follicle (≥ 12.5 mm; n = 66). The first increase (P < 0.0001) in serum bPAG occurred in pregnant cows on d 24 after insemination and circulating bPAG decreased before a decrease in progesterone in 3 of 4 cows that lost an embryo or fetus. Pattern of secretion of bPAG in serum from d 24 to 60 after insemination (d 0) was affected by day (P < 0.0001), but not ovulatory follicle size. In Exp. 3, suckled beef cows (n = 1164) were administered the CO-Synch protocol either with (donor cows; n = 810) or without (recipient cows; n = 354) AI on d 0. Single embryos (n = 394) or oocytes (n = 45) were recovered from the donor cows [d 7; embryo transfer (ET)] and all live embryos were transferred into recipients the same day. Cows were classified on d 0 as having a small (<12.5 mm) or large (≥ 12.5 mm) ovulatory follicle, and randomly chosen as donors or recipients to remove confounding effects of ovulatory follicle size on fertility. Serum concentration of bPAG at d 28 was not affected by ovulatory follicle size (P = 0.85), embryo stage at ET (P = 0.75), embryo quality at ET (P = 0.64), estradiol at GnRH2 (P = 0.62) or serum progesterone at ET (d7; P = 0.14). Compared with cows that maintained pregnancy (n = 176), cows that exhibited late embryonic or fetal mortality (n = 19) after d 28 had decreased (P < 0.05) concentrations of bPAG on d 28. In summary, there was no relationship between serum bPAG and ovulatory follicle size or embryo stage or quality at ET; however, cows that lost an embryo after d 28 had reduced concentrations of bPAG on d 28 compared with cows that maintained pregnancy.

  19. Dose enhancement close to platinum implants for the 4, 6, and 10 MV stereotactic radiosurgery

    SciTech Connect

    Cheung, Joel Y.C.; Ng, Ben K.P.; Yu, K.N.

    2004-10-01

    Three photon interaction processes, namely, the photoelectric effect, Compton effect, and pair production, can occur when materials with high atomic numbers are irradiated by the high- and low-energy bremsstrahlung photons from a linear accelerator. A dose enhancement, due to the photoelectric effect and pair production, near targets with platinum implants (with a high atomic number) in radiosurgery cannot be predicted by the XKnife{sup reg} radiosurgery treatment planning system. In the present work, Monte Carlo simulations using PRESTA EGS4 were employed to investigate the resulting dose enhancements from 4, 6, and 10 MV energies commonly used in the stereotactic radiosurgery system. Dose enhancements from 32% to 68% were observed close to the platinum implant for the above energies when using a 12.5 mm collimator. Comparatively higher dose enhancements were observed when using smaller collimators. It was found that this dose enhancement increased with beam energy but decreased as beam size increased.

  20. First study on oyster-shell-based phosphorous removal in saltwater - A proxy to effluent bioremediation of marine aquaculture.

    PubMed

    Martins, Marta C; Santos, Eduarda B H; Marques, Catarina R

    2017-01-01

    The efficiency of oyster-shell waste for the removal of phosphorous (P) in saltwater was herein evaluated. For that, different factors were tested, being attained >56% and >98% P removal by natural oyster shell (NOS)-fraction <0.125mm and COS (calcined oyster shell)-fraction 0.5mm, respectively. Adsorption was the main mechanism suggested for NOS, whilst a co-mechanism of precipitation occurred with COS. NOS adsorption was consistent with Langmuir model and followed both the Elovich and Intraparticle Difusion kinetic models. COS followed only Pseudo-Second Order and, mainly, the Elovich model. Overall, optimal conditions for P removal from saltwater were established for NOS and COS, which will unquestionably allow to comply with regulated P levels for the discharge of wastewater from saltwater RAS. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Characterization of MgB2 Conductors for Coil Development

    NASA Astrophysics Data System (ADS)

    Aslanoglu, Z.; Arda, L.; Akin, Y.; Sumption, M. D.; Tomsic, M.; Hascicek, Y. S.

    2004-06-01

    The effects of the heat treatment conditions on microstructure and the transport critical current density of MgB2 wires, which were fabricated by the Continuous Tube Forming and Filling (CTFF) process, have been investigated. Two types of MgB2 conductors, Fe/MgB2 and Cu/MgB2, were studied. It was found that the sheath materials affect the optimum annealing profile of MgB2 conductor. The annealing temperature for Cu/MgB2 conductors was lower than that for the Fe/MgB2 conductors. The critical current density, Jc was measured to be 1.1×105 A/cm2 at 20 K in-self field for Cu/MgB2 conductor of 1.25 mm in diameter. The processing, microstructure and superconducting properties are presented.

  2. Diet of double-crested cormorants wintering in Texas

    USGS Publications Warehouse

    Campo, J.J.; Thompson, B.C.; Barron, J.C.; Telfair II, R. C.; Durocher, P.; Gutreuter, S.

    1993-01-01

    The diets of 420 Double-crested Cormorants (Phalacrocorax auritus) were studied during November 1986-March 1987 on eight public reservoirs in Texas. Prey included 29 fish species and the mean live weight of fish per bird was 122 g. Fishes a??415 mm long were ingested, but those a??125 mm accounted for 90% of cormorant food contents by number. Shad (Dorosoma spp.) and sunfishes (Lepomis spp.) accounted for 90% of the total food items by number. Consumption of fishes (percent by weight) was different for male vs. female and adult vs. juvenile cormorants. Total consumption of fish by weight was consistent throughout the period; however, fewer but much larger fish were consumed after 15 February. Cormorants ate fishes that were most abundant in reservoirs. Sport fishes made up a substantial portion of cormorant food by weight, but not by number on some reservoirs. Cormorants ate very few large sport fish, however.

  3. PIT Tagging Anurans

    USGS Publications Warehouse

    McCreary, Brome

    2008-01-01

    The following video demonstrates a procedure to insert a passive integrated transponder (PIT) tag under the skin of an anuran (frog or toad) for research and monitoring purposes. Typically, a 12.5 mm tag (0.5 in.) is used to uniquely identify individual anurans as smal as 40 mm (1.6 in.) in length from snout to vent. Smaller tags are also available and allow smaller anurans to be tagged. The procedure does not differ for other sizes of tages or other sizes of anurans. Anyone using this procedure should ensure that the tag is small enough to fit easily behind the sacral hump of the anuran, as shown in this video.

  4. Photoacoustic imaging of carotid artery atherosclerosis

    NASA Astrophysics Data System (ADS)

    Kruizinga, Pieter; van der Steen, Antonius F. W.; de Jong, Nico; Springeling, Geert; Robertus, Jan Lukas; van der Lugt, Aad; van Soest, Gijs

    2014-11-01

    We introduce a method for photoacoustic imaging of the carotid artery, tailored toward detection of lipid-rich atherosclerotic lesions. A common human carotid artery was obtained at autopsy, embedded in a neck mimicking phantom and imaged with a multimodality imaging system using interstitial illumination. Light was delivered through a 1.25-mm-diameter optical probe that can be placed in the pharynx, allowing the carotid artery to be illuminated from within the body. Ultrasound imaging and photoacoustic signal detection is achieved by an external 8-MHz linear array coupled to an ultrasound imaging system. Spectroscopic analysis of photoacoustic images obtained in the wavelength range from 1130 to 1250 nm revealed plaque-specific lipid accumulation in the collagen structure of the artery wall. These spectroscopic findings were confirmed by histology.

  5. Development and validation of stability-indicating HPLC method for determination of cefpirome sulfate.

    PubMed

    Zalewski, Przemysław; Skibiński, Robert; Cielecka-Piontek, Judyta; Bednarek-Rajewska, Katarzyna

    2014-01-01

    The stability-indicating LC assay method was developed and validated for quantitative determination of cefpirome sulfate (CPS) in the presence of degradation products formed during the forced degradation studies. An isocratic HPLC method was developed with Lichrospher RP-18 column, 5 μm particle size, 125 mm x 4 mm column and 12 mM ammonium acetate-acetonitrile (90 : 10 v/v) as a mobile phase. The flow rate of the mobile phase was 1.0 mL/min. Detection wavelength was 270 nm and temperature was 30 degrees C. Cefpirome sulfate as other cephalosporins was subjected to stress conditions of degradation in aqueous solutions including hydrolysis, oxidation, photolysis and thermal degradation. The developed method was validated with regard to linearity, accuracy, precision, selectivity and robustness. The method was applied successfully for identification and determination of cefpirome sulfate in pharmaceuticals and during kinetic studies.

  6. Recovery Act: Novel Kerf-Free PV Wafering that provides a low-cost approach to generate wafers from 150um to 50um in thickness

    SciTech Connect

    Fong, Theodore E.

    2013-05-06

    The technical paper summarizes the project work conducted in the development of Kerf-Free silicon wafering equipment for silicon solar wafering. This new PolyMax technology uses a two step process of implantation and cleaving to exfoliate 50um to 120um wafers with thicknesses ranging from 50um to 120um from a 125mm or 156mm pseudo-squared silicon ingot. No kerf is generated using this method of wafering. This method of wafering contrasts with the current method of making silicon solar wafers using the industry standard wire saw equipment. The report summarizes the activity conducted by Silicon Genesis Corporation in working to develop this technology further and to define the roadmap specifications for the first commercial proto-type equipment for high volume solar wafer manufacturing using the PolyMax technology.

  7. Response function measurements of an NE102A organic scintillator using an 241Am-Be source

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Aksoy, A.; Khiari, F. Z.; Coban, A.; Nagadi, M. M.; Al-Ohali, M. A.; Al-Jalal, M. A.

    1994-07-01

    The response function of a 125 mm diameter NE102A organic scintillation detector has been measured over the 2.7-14.8 MeV neutron energy range. The detector response function was derived from the light output for monoenergetic neutrons and gamma rays. The light output of the detector for monoenergetic neutrons was measured by selecting narrowgates in the time-of-flight (TOF) spectrum for a 241Am-Be neutron source. In order to provide check points on the data, the detector light output was also measured for monoenergetic neutrons from the D(d, n) and T(d, n) reactions. The response function of the NE102A detector is in good agreement (within 1-5%) with the published data of Cecil et al. [Nucl. Instr. and Meth. 161 (1979) 439].

  8. Experimental investigation on heat transfer analysis of conical coil heat exchanger with 90° cone angle

    NASA Astrophysics Data System (ADS)

    Purandare, Pramod S.; Lele, Mandar M.; Gupta, Raj Kumar

    2015-03-01

    In the present study, an experimental investigation on thermal performance of the conical coil heat exchanger with 90° conical coil heat exchanger is reported. Three different conical coil heat exchangers of same mean coil diameter (Dm = 200 mm) with different tube diameters ( di = 8, 10, 12.5 mm) are analyzed under steady state condition. The analysis is carried out for the tube side hot fluid flow range of 10-100 lph ( Re = 500-5,000), while the shell side flow range of 30-90 lph. The data available from experimentation leads to evaluate heat transfer coefficients for inside and outside the tube of the conical coil heat exchanger by Wilsons plot method. The calculations are further extended to estimate Nusselt Number ( Nu) and effectiveness. The empirical correlations are proposed for predicting Nu and the outlet temperatures of hot and cold fluids. The predicted empirical correlations show reasonable agreement with the experimental results within the given range of parameters.

  9. Treatment of hardware infection after osteosynthesis of lower leg using negative pressure wound therapy and transforming powder dressing.

    PubMed

    Marinović, Marin; Ivandcić, Aldo; Spanjol, Josip; Pina, Maja; Bakota, Bore; Bandalović, Ante; Cukeljs, Fabijan

    2014-12-01

    Fractures of the distal part of the lower leg are more common in everyday practice and traumatology. In young and active patients these injuries are mainly caused by high energy trauma. They are treated with external fixator in first step, and in second step, after sanation of the soft tissue, with open reduction and internal fixation (ORIF). It is very safe and effective method of treatment. Treatment of the infections that occur in the early postoperative period after open reduction and internal fixation represents a great problem and challenge for surgeons. It is widely accepted that the presence of deep infection can't be cured in the presence of hardware. However, removal of hardware in the presence of unhealed fractures significantly complicates sanation of infection and fracture itself We have decided to present a 35-years-old patient with a hardware infection with present chronic wound with hardware exposed eight months after the first operation and six months after second operation. The wound measured one centimeter in diameter with cell detritus and bad granulations tissue inside the wound. Hardwre was exposed in the depth of the wound.The secretion was minimal. Negative Pressure Wound Therapy (NPWT) was applicated after debridemet and lavage performed in ambulatory conditions. The starting therapy was continuously -125 mm Hg of vacuum. After five days of NPWT the defect was partially filled with granula- tion tissue. For another five days we continue with NPWT with the same values of-125 mm Hg pressure but in the inter- mitent mode. After that period we used transforming powder dressing for covering and protection of the wound with was filled with granulation tissue. Five days later, wound was completely healed with epithelisation. After four months of patient follow-up, we found the wound is completely repaired. The patient denies pain and has continued orderly flow of fracture healing, with no signs of infection.

  10. Pixel CdTe semiconductor module to implement a sub-MeV imaging detector for astrophysics

    NASA Astrophysics Data System (ADS)

    Gálvez, J.-L.; Hernanz, M.; Álvarez, L.; Artigues, B.; Álvarez, J.-M.; Ullán, M.; Pellegrini, G.; Lozano, M.; Cabruja, E.; Martínez, R.; Chmeissani, M.; Puigdengoles, C.

    2017-03-01

    Stellar explosions are relevant and interesting astrophysical phenomena. Since long ago we have been working on the characterization of nova and supernova explosions in X and gamma rays, with the use of space missions such as INTEGRAL, XMM-Newton and Swift. We have been also involved in feasibility studies of future instruments in the energy range from several keV up to a few MeV, in collaboration with other research institutes, such as GRI, DUAL and e-ASTROGAM. High sensitivities are essential to perform detailed studies of cosmic explosions and cosmic accelerators, e.g., Supernovae, Classical Novae, Supernova Remnants (SNRs), Gamma-Ray Bursts (GRBs). In order to fulfil the combined requirement of high detection efficiency with good spatial and energy resolution, an initial module prototype based on CdTe pixel detectors is being developed. The detector dimensions are 12.5mm x 12.5mm x 2mm, with a pixel pitch of 1mm x 1mm. Each pixel is bump bonded to a fanout board made of Sapphire substrate and routed to the corresponding input channel of the readout ASIC, to measure pixel position and pulse height for each incident gamma-ray photon. An ohmic CdTe pixel detector has been characterised by means of 57Co, 133Ba and 22Na sources. Based on this, its spectroscopic performance and the influence of charge sharing is reported here. The pixel study is complemented by the simulation of the CdTe module performance using the GEANT 4 and MEGALIB tools, which will help us to optimise the pixel size selection.

  11. A new 3D texture feature based computer-aided diagnosis approach to differentiate pulmonary nodules

    NASA Astrophysics Data System (ADS)

    Han, Fangfang; Wang, Huafeng; Song, Bowen; Zhang, Guopeng; Lu, Hongbing; Moore, William; Zhao, Hong; Liang, Zhengrong

    2013-02-01

    To distinguish malignant pulmonary nodules from benign ones is of much importance in computer-aided diagnosis of lung diseases. Compared to many previous methods which are based on shape or growth assessing of nodules, this proposed three-dimensional (3D) texture feature based approach extracted fifty kinds of 3D textural features from gray level, gradient and curvature co-occurrence matrix, and more derivatives of the volume data of the nodules. To evaluate the presented approach, the Lung Image Database Consortium public database was downloaded. Each case of the database contains an annotation file, which indicates the diagnosis results from up to four radiologists. In order to relieve partial-volume effect, interpolation process was carried out to those volume data with image slice thickness more than 1mm, and thus we had categorized the downloaded datasets to five groups to validate the proposed approach, one group of thickness less than 1mm, two types of thickness range from 1mm to 1.25mm and greater than 1.25mm (each type contains two groups, one with interpolation and the other without). Since support vector machine is based on statistical learning theory and aims to learn for predicting future data, so it was chosen as the classifier to perform the differentiation task. The measure on the performance was based on the area under the curve (AUC) of Receiver Operating Characteristics. From 284 nodules (122 malignant and 162 benign ones), the validation experiments reported a mean of 0.9051 and standard deviation of 0.0397 for the AUC value on average over 100 randomizations.

  12. Landfill mining: Case study of a successful metals recovery project.

    PubMed

    Wagner, Travis P; Raymond, Tom

    2015-11-01

    Worldwide, the generation of municipal solid waste (MSW) is increasing and landfills continue to be the dominant method for managing solid waste. Because of inadequate diversion of reusable and recoverable materials, MSW landfills continue to receive significant quantities of recyclable materials, especially metals. The economic value of landfilled metals is significant, fostering interest worldwide in recovering the landfilled metals through mining. However, economically viable landfill mining for metals has been elusive due to multiple barriers including technological challenges and high costs of processing waste. The objective of this article is to present a case study of an economically successful landfill mining operation specifically to recover metals. The mining operation was at an ashfill, which serves a MSW waste-to-energy facility. Landfill mining operations began in November 2011. Between December 2011 and March 2015, 34,352 Mt of ferrous and non-ferrous metals were recovered and shipped for recycling, which consisted of metals >125 mm (5.2%), 50-125 mm (85.9%), <50mm (3.4%), zorba (4.6%), and mixed products (0.8%). The conservative estimated value of the recovered metal was $7.42 million. Mining also increased the landfill's airspace by 10,194 m(3) extending the life of the ashfill with an estimated economic value of $267,000. The estimated per-Mt cost for the extraction of metal was $158. This case study demonstrates that ashfills can be profitably mined for metals without financial support from government. Although there are comparatively few ashfills, the results and experience obtained from this case study can help foster further research into the potential recovery of metals from raw, landfilled MSW.

  13. SU-E-T-637: Proton Aperture Quality Assurance Using Computed Tomography

    SciTech Connect

    Reyhan, M; Yue, N; Zou, J

    2015-06-15

    Purpose: To develop an automated algorithm for aperture quality assurance for double scattering proton radiotherapy. Methods: Anterior-Posterior scout images were acquired on a CT scanner for five brass apertures (2 large, 3 small) with 120 kVp and 10mA. A semi-automated algorithm was developed for the QA process. The input includes a user selecting the scout image and the associated patient plan, field and aperture size. The program automatically thresholds the scout image. Next, a connectivity algorithm is used to determine the points associated with the central shape to obtain the contour. To compare with the plan contour, the program converts the detected and plan contours into polar coordinates, interpolates the data to a 1 degree spaced grid, and determines the differences in radial distance at each grid point. Results: The mean and maximum difference and the percentage of points with distance differences less than 1.25 mm (due to the divergent cut of the aperture) between the detected and plan field aperture contours were obtained. A repeatability coefficient was derived based on repeated scanning and processing of three of the apertures. The mean difference for five apertures was 0.44 +/−0.08 mm. The maximum difference in distance was 1.2 +/−0.23 mm for all apertures. The Repeatability Coefficient was +/−0.038 mm, indicating the technique is highly repeatable. The mean percent of points with distance less than 1.25 mm was 97.41 +/−0.35%. Conclusion: Automated CT scout image based proton aperture QA is feasible, saves time, and provides a quantitative metric for proton patient specific aperture QA.

  14. Critical Height for the Unstabilization of Prominences

    NASA Astrophysics Data System (ADS)

    Liu, K.; Wang, Y.; Shen, C.

    2010-12-01

    At which altitude will a prominence probably erupt? This question is statistically studied based on the 10072 solar limb prominences recognized by SLIPCAT from 2007 April to the end of 2009. We manually check all the prominences with leading edge greater than 1.2 Rs, and find that there are 256 disrupted prominences (DPs) and 106 stable prominences (SPs). Among the DPs, there are 149 prominences (EPs) showing a clear and successful eruption process in the STEREO/EUVI field of view and 107 prominences (FPs) presenting a failed eruption. The eruption process of EPs can be further classified into 3 types, single eruption (SE), multiple eruptions (ME) and gradual eruption (GE). When the main body of a EP first begins to ascend rapidly with a uniform velocity, we define the height of the prominence’s leading edge at this moment as the unstabilization height. FPs also have unstabilization heights as well. All the unstabilization heights are identified by hands. It is found that 65% DPs are unstabilized between 49 and 90 Mm. The comparison of the number of DPs with all the well-tracked prominences suggests that the ratio between them is a double-peak distribution with the most probable heights for a prominence being unstable at 83 and 125 Mm. The above two results suggest that there are two critical heights for the unstabilization of prominences: the primary height is 83 Mm and the secondary height is 125 Mm. We think two different heights present two kinds of prominences, the primary one corresponding to DPs around or at active region and the secondary one corresponding to DPs at quiet region. We also find eruption velocity of DPs is anti-correlated with the unstabilization height and the total brightness, which means that prominences with less mass and lower unstabilization height would require larger inputting energy and large eruption velocity. The association of EPs with CME in this study is 49%.

  15. Comparison of functional deficits in the rabbit tibialis anterior following tourniquet ischemia and tourniquet compression.

    PubMed

    Ohara, W M; Pedowitz, R A; Oyama, B K; Gershuni, D H

    1996-07-01

    The purpose of this study was to measure the contractile properties of skeletal muscle after direct compression with a tourniquet and to compare these properties with those found after a similar period of tourniquet ischemia. A rabbit model of tourniquet compression of the tibialis anterior was developed and tested for this investigation. Fifty-seven animals then were divided into four protocol groups: (a) thigh tourniquet (ischemia) at 350 mm Hg (46.7 kPa), (b) leg tourniquet (compression) at 350 mm Hg (46.7 kPa), (c) leg tourniquet at 125 mm Hg (16.7 kPa), and (d) controls. A significant decrease in maximum tetanic tension was demonstrated in all three experimental groups. Direct compression at 350 mm Hg resulted in the greatest decline in maximum tetanic tension (22.6% of control), followed by compression at 125 mm Hg (30.5%) and ischemic injury (40.2%). In addition, direct compression at 350 mm Hg resulted in a significantly greater loss of force-generating capacity when compared with the ischemic group (p < 0.01). A similar pattern was noted for the rate of rise in maximum tetanic tension. Gross histologic examination of the tibialis anterior sections was consistent with the results of functional testing, with the more severe abnormalities noted in the compressed specimens. These results clearly demonstrate that tourniquet compression injury results in a more significant loss of functional strength and contractile speed than tourniquet ischemia. Further investigations on the safe limits of tourniquet use thus should be directed toward measuring the effect of the pneumatic tourniquet on the underlying soft tissues.

  16. Overview of the ion projection lithography European MEDEA and international program

    NASA Astrophysics Data System (ADS)

    Kaesmaier, Rainer; Loeschner, Hans

    2000-07-01

    Ion Projection Lithography (IPL) follows the same principle as optical wafer steppers when using hydrogen or helium ions for the reduction printing of stencil mask patterns to wafer substrates: (1) DUV resists can be used with ion beam exposure; (2) well established optical wafer alignment techniques are used; (3) the mask is stable during exposure. IPL is the only NGL technique where the mask is not scanned during exposure. Because of the very small particle wavelength (5 * 10-5 nm for 100 keV He+ ions there is the possibility of using electrostatic ion-optics with very small numerical aperture (NA approximately equals 10-5). The ion-optics is based on aluminum lens electrode and standard insulator materials. Mechanical tolerances on lens electrode manufacturing and adjustment are in the micrometer range because of in-situ electronic column fine adjustment possibilities. Wafer stage movements with micrometer precision is sufficient through feedback from precise laser interferometer stage position measurements to electronic image placement of the ion image projected to the wafer with on-line 'pattern lock' control. As part of the MEDEA project an IPL process development tool (PDT) is being integrated by IMS with the target to achieve 50 nm resolution within a 12.5 mm exposure field. The IPL production stepper will be based on a similar but more compact ion-optical column, exposing large (e.g. 25 mm) chip fields by stitching of 12.5 mm fields. A 300 mm wafer throughput of 30 WPH is feasible also for the 50 nm node. IPL has the potential of achieving the lowest NGL cost of ownership with the longest multi-generational life time. The practical resolution limit of the IPL technique is below 35 nm.

  17. SU-E-T-391: Evaluation of Image Parameters Impact On the CT Calibration Curve for Proton Therapy

    SciTech Connect

    Xiao, Z; Reyhan, M; Huang, Q; Zhang, M; Yue, N; Chen, T

    2015-06-15

    Purpose: The calibration of the Hounsfield units (HU) to relative proton stopping powers (RSP) is a crucial component in assuring the accurate delivery of proton therapy dose distributions to patients. The purpose of this work is to assess the uncertainty of CT calibration considering the impact of CT slice thickness, position of the plug within the phantom and phantom sizes. Methods: Stoichiometric calibration method was employed to develop the CT calibration curve. Gammex 467 tissue characterization phantom was scanned in Tomotherapy Cheese phantom and Gammex 451 phantom by using a GE CT scanner. Each plug was individually inserted into the same position of inner and outer ring of phantoms at each time, respectively. 1.25 mm and 2.5 mm slice thickness were used. Other parameters were same. Results: HU of selected human tissues were calculated based on fitted coefficient (Kph, Kcoh and KKN), and RSP were calculated according to the Bethe-Bloch equation. The calibration curve was obtained by fitting cheese phantom data with 1.25 mm thickness. There is no significant difference if the slice thickness, phantom size, position of plug changed in soft tissue. For boney structure, RSP increases up to 1% if the phantom size and the position of plug changed but keep the slice thickness the same. However, if the slice thickness varied from the one in the calibration curve, 0.5%–3% deviation would be expected depending on the plug position. The Inner position shows the obvious deviation (averagely about 2.5%). Conclusion: RSP shows a clinical insignificant deviation in soft tissue region. Special attention may be required when using a different slice thickness from the calibration curve for boney structure. It is clinically practical to address 3% deviation due to different thickness in the definition of clinical margins.

  18. Characterization of graded multicenter animal spinal cord injury study contusion spinal cord injury using somatosensory-evoked potentials.

    PubMed

    Agrawal, Gracee; Kerr, Candace; Thakor, Nitish V; All, Angelo H

    2010-05-15

    Electrophysiological analysis using somatosensory-evoked potentials (SEPs) and behavioral assessment using Basso, Beattie, Bresnahan (BBB) scale were compared over time for graded Multicenter Animal Spinal Cord Injury Study (MASCIS) contusion spinal cord injury (SCI). To study the SEP responses across different contusion injury severities and to compare them with BBB scores. For any SCI therapy evaluation, it is important to accurately and objectively standardize the injury model. The graded MASCIS contusion injuries on dorsal spine have been standardized using BBB, which is subjective and prone to human errors. Furthermore, dorsal pathway disruption does not always produce locomotor deficits. SEP monitoring provides an advantage of providing a reliable and objective assessment of the functional integrity of dorsal sensory pathways. Four groups of Fischer rats received contusion at T8 using New York University (NYU)-MASCIS impactor from impact heights of 6.25 mm (mild), 12.5 mm (moderate), 25 mm (severe), or 50 mm (very severe). The control group underwent laminectomy only. SEP and BBB recordings were performed once before injury, and then weekly for up to 7 weeks. Graded levels of injury produced concomitant attenuations in hindlimb SEP amplitudes. Following injury, 25 and 50 mm groups together differed significantly from 12.5 and 6.25 mm groups (P < 0.01). From week 5, differences between 12.5 and 6.25 mm groups also became apparent (P < 0.01), which showed significant electrophysiological improvement. However, no significant differences were observed between 25 and 50 mm groups, which showed negligible electrophysiological recovery. Although comparable differences between different groups were also detected by BBB after injury (P < 0.001), BBB was less sensitive in detecting any improvement in 6.25 and 12.5 mm groups. SEP amplitudes and BBB scores decrease corresponding to increase in injury severity, however, these show different temporal patterns of recovery. These results demonstrate the utility of SEPs in conjunction with BBB, to monitor therapeutic interventions in SCI research.

  19. Effect of plunger diameter on the push-out bond values of different root filling materials.

    PubMed

    Nagas, E; Uyanik, O; Durmaz, V; Cehreli, Z C

    2011-10-01

    To evaluate the effect of plunger diameter on the push-out bond strength of different root filling materials to root canal dentine. Freshly extracted human incisors (n=90) were decoronated, and the root canals were enlarged with post drills. Prepared roots were placed into a custom alignment apparatus to embed the roots vertically within self-curing acrylic resin. The specimens were randomly assigned into three groups according to the root filling system used: gutta-percha/AH Plus; Resilon/Epiphany; and fibre-reinforced composite (FRC)/Duolink resin cement. After filling, the specimens were further subdivided according to the diameter of the plunger used to employ the debonding force: 0.75, 1 and 1.25 mm. Intra-radicular bond strength was measured using the push-out test at a cross-head speed of 1 mm min(-1) . The data were analysed statistically using Kruskal-Wallis test with Bonferroni correction at P = 0.05. Regardless of the plunger diameter, FRC yielded the highest bond strength, followed by gutta-percha and Resilon, respectively (P<0.001). In all groups, greater plunger diameter resulted in an apparent increased bond strength, but the differences were only significant in the FRC group, with the 1.25-mm plunger generating higher debonding values compared with that of its 0.75- and 1-mm versions (P<0.001). In the gutta-percha and Resilon groups, the majority of specimens had adhesive failures. Roots filled with FRC exhibited more cohesive failures than those of the other test groups. Different plunger diameters are associated with significantly different intra-radicular push-out bond strengths of root filling systems. © 2011 International Endodontic Journal.

  20. TU-A-12A-07: CT-Based Biomarkers to Characterize Lung Lesion: Effects of CT Dose, Slice Thickness and Reconstruction Algorithm Based Upon a Phantom Study

    SciTech Connect

    Zhao, B; Tan, Y; Tsai, W; Lu, L; Schwartz, L; So, J; Goldman, J; Lu, Z

    2014-06-15

    Purpose: Radiogenomics promises the ability to study cancer tumor genotype from the phenotype obtained through radiographic imaging. However, little attention has been paid to the sensitivity of image features, the image-based biomarkers, to imaging acquisition techniques. This study explores the impact of CT dose, slice thickness and reconstruction algorithm on measuring image features using a thorax phantom. Methods: Twentyfour phantom lesions of known volume (1 and 2mm), shape (spherical, elliptical, lobular and spicular) and density (-630, -10 and +100 HU) were scanned on a GE VCT at four doses (25, 50, 100, and 200 mAs). For each scan, six image series were reconstructed at three slice thicknesses of 5, 2.5 and 1.25mm with continuous intervals, using the lung and standard reconstruction algorithms. The lesions were segmented with an in-house 3D algorithm. Fifty (50) image features representing lesion size, shape, edge, and density distribution/texture were computed. Regression method was employed to analyze the effect of CT dose, slice of thickness and reconstruction algorithm on these features adjusting 3 confounding factors (size, density and shape of phantom lesions). Results: The coefficients of CT dose, slice thickness and reconstruction algorithm are presented in Table 1 in the supplementary material. No significant difference was found between the image features calculated on low dose CT scans (25mAs and 50mAs). About 50% texture features were found statistically different between low doses and high doses (100 and 200mAs). Significant differences were found for almost all features when calculated on 1.25mm, 2.5mm, and 5mm slice thickness images. Reconstruction algorithms significantly affected all density-based image features, but not morphological features. Conclusions: There is a great need to standardize the CT imaging protocols for radiogenomics study because CT dose, slice thickness and reconstruction algorithm impact quantitative image features to various degrees as our study has shown.

  1. Using Mid-Upper Arm Circumference to End Treatment of Severe Acute Malnutrition Leads to Higher Weight Gains in the Most Malnourished Children

    PubMed Central

    Dale, Nancy M.; Myatt, Mark; Prudhon, Claudine; Briend, André

    2013-01-01

    Objective The World Health Organization recommends discharging children admitted to nutrition programs treating severe acute malnutrition, with a low mid-upper arm circumference (MUAC <115 mm) when weight gain is >15%. When this recommendation is followed, the most severely malnourished children receive a shorter treatment compared to children that are less severely malnourished. This study assesses whether using MUAC >125 mm as discharge criteria eliminates this effect. Methods and Findings Data from 753 children cured from a Médecins Sans Frontières outpatient nutrition program in Gedaref, North Sudan were analyzed. MUAC >125 mm was used as discharge criteria. Length of stay and percent weight gain of children were compared in relation to nutritional status on admission. Children with low MUAC on admission had a longer duration of treatment (p = 0.000) and also a higher percent weight gain (p = 0.000) than children with higher MUAC. Similar results with weight-for-height z-scores categories were shown with both duration of treatment (p = 0.000) and percent weight gain (p = 0.000). Conclusion This study shows that using MUAC as the discharge criteria eliminates the effect of shorter treatment in most severely malnourished children compared to least severely malnourished, as is observed with percent weight gain. The findings directly address the main concern that has been identified with the current WHO recommendation of using percent weight gain. MUAC could be used as discharge criteria, instead of percent weight gain, as having a longer duration of treatment and a higher percent weight gain for the most malnourished is highly desirable. PMID:23418442

  2. Participation in multilateral effort to develop high performance integrated CPC evacuated collectors

    NASA Astrophysics Data System (ADS)

    Winston, R.; Ogallagher, J. J.

    1992-05-01

    The University of Chicago Solar Energy Group has had a continuing program and commitment to develop an advanced evacuated solar collector integrating nonimaging concentration into its design. During the period from 1985-1987, some of our efforts were directed toward designing and prototyping a manufacturable version of an Integrated Compound Parabolic Concentrator (ICPC) evacuated collector tube as part of an international cooperative effort involving six organizations in four different countries. This 'multilateral' project made considerable progress towards a commercially practical collector. One of two basic designs considered employed a heat pipe and an internal metal reflector CPC. We fabricated and tested two large diameter (125 mm) borosilicate glass collector tubes to explore this concept. The other design also used a large diameter (125 mm) glass tube but with a specially configured internal shaped mirror CPC coupled to a U-tube absorber. Performance projections in a variety of systems applications using the computer design tools developed by the International Energy Agency (IEA) task on evacuated collectors were used to optimize the optical and thermal design. The long-term goal of this work continues to be the development of a high efficiency, low cost solar collector to supply solar thermal energy at temperatures up to 250 C. Some experience and perspectives based on our work are presented and reviewed. Despite substantial progress, the stability of research support and the market for commercial solar thermal collectors were such that the project could not be continued. A cooperative path involving university, government, and industrial collaboration remains the most attractive near term option for developing a commercial ICPC.

  3. ED 03-2 HOME BLOOD PRESSURE MONITORING IS BETTER THAN OFFICE BP AND AMBULATORY BP: UPDATE.

    PubMed

    Kario, Kazuomi

    2016-09-01

    Out-of-office blood pressure (BP) measured by home BP monitoring (HBPM) or ambulatory BP monitoring (ABPM) was demonstrated to be superior to office BP for the prediction of cardiovascular events. The ABPM is superior to HBPM for detecting the all the BP-related risks throughout 24-hr, and the self-measured HBPM underestimates the risk of daytime stress hypertension and nocturnal hypertension. However, ABPM cannot always be provided in clinical practice, and home BP monitoring can be superior to ABPM as part of a home BP-guided antihypertension strategy in clinical practice. In clinical practice, we should use both ABPM and HBPM considering these device properties. We have developed the new ABPM device which is alternatively used as self-measure HBPM (Kario. Prog Cardiovasc Dis 2016, in press).The importance of on-treatment HBPM for the cardiovascular prognosis of hypertensive individuals was recently revealed in the largest real-world prospective study held to date, the Home blood pressure measurement with Olmesartan Naive patients to Establish Standard Target blood pressure (HONEST) study. That study of more than 21 000 hypertensive patients used HBPM, and the results demonstrated that when morning home systolic BP was well-controlled during the 2-year follow-up at < 125 mmHg, there was no increase in cardiovascular events even among the patients whose office systolic BP was ≥150 mmHg, compared with those with office systolic BP < 130 mmHg and morning home systolic BP < 125 mmHg. On the other hand, even when the office systolic BP of the HONEST study's hypertensive patients was well controlled at < 130 mmHg, the hazard ratio of cardiovascular events was 2.5 in the masked uncontrolled hypertension patients with morning systolic BP ≥145 mmHg compared with the well-controlled patients with morning systolic BP < 125 mmHg (Kario, et al. Hypertension 2014;64:989-996). The threshold of on-treatment morning BP for a significant increase in

  4. Hertzian contact response and damage tolerance of dental ceramics.

    PubMed

    Coldea, Andrea; Swain, Michael V; Thiel, Norbert

    2014-06-01

    To determine the contact response and damage tolerance or strength degradation of a range of dental CAD/CAM ceramic materials including novel polymer-infiltrated-ceramic-network (PICN) materials by means of spherical indentations at various loads and indenter radii. The seven tested materials included Mark II, PICN test materials 1 and 2, In-Ceram Alumina, VM 9, In-Ceram YZ (Vita Zahnfabrik, Bad Saeckingen, Germany) and IPS e.max CAD, (Ivoclar Vivadent, Schaan, Liechtenstein). To evaluate the damage tolerance and role of indenter size, indentations with tungsten carbide spheres (0.5mm and 1.25mm radius) were placed on bending bars with varying loads (1.96-1000N). The indented bending bars were subsequently loaded to fracture in three-point bending. The contact induced damage was analyzed by light microscopy (LM) and SEM. The spherical contact response was measured on polished surfaces. The initial strengths for the individual materials were found to reduce above specific indentation loads, which were a function of the indenter radius. Employing a 0.5mm radius sphere resulted in the following strength degrading loads and ordering of materials: VM9 (98N)

  5. Efficacy and safety of negative pressure wound therapy for Szilagyi grade III peripheral vascular graft infection.

    PubMed

    Cheng, Hsu-Tang; Hsu, Yung-Chang; Wu, Chao-I

    2014-12-01

    A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether it is safe and effective to use negative pressure wound therapy (NPWT) for Szilagyi grade III (i.e. the arterial implant proper involved in the infection) peripheral vascular graft infection. Altogether, 69 papers were found using the reported search. From the search results, reference lists of potentially eligible studies and related citations in PubMed, seven papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. In the only randomized, controlled trial that compared NPWT (n = 10) and alginate dressing change (n = 10), the NPWT group demonstrated shorter time to full skin epithelialization (median 57 vs 104 days; P = 0.026). In the other six case series, the recruited case number ranged from 12 to 72. The mode of NPWT varied among the included studies, with the majority using a continuous negative pressure of 125 mmHg. One study combined NPWT and sartorius myoplasty, another used sartorius myoplasty in selected cases and others did not. The mean duration of using NPWT ranged from 14.2 to 43 days. The mean duration to achieve complete wound healing ranged from 24 (the study with sartorius myoplasty) to 51 days. The NPWT treatment failure rate ranged from 0 (the study with sartorius myoplasty) to 25%. The major complication of NPWT was bleeding and the incidence rate was reported to be <10%. We conclude that the amount of evidence for recommending NPWT alone as the first-line treatment for Szilagyi grade III peripheral vascular graft infection is small with only one small-sized randomized controlled trial demonstrating that NPWT alone is superior to alginate dressing change in shortening the time to complete wound healing by 2 months. Limited evidence (case series with >1 year of

  6. Treating Fasciotomy Wounds with Negative Pressure Wound Therapy with Instillation and Dwell Time (NPWTi-d)

    PubMed Central

    2016-01-01

    Acute compartment syndrome (ACS) is a serious complication of lower-extremity trauma caused by accidents or post-procedure complications. ACS is characterized by increased pressure within the compartment, resulting in reduced blood flow, tissue hypoxia, and tissue necrosis. Fasciotomies to relieve pressure and debridement of necrotic tissue comprise primary treatment. My purpose is to present initial experience using negative pressure wound therapy with instillation and dwell time (NPWTi-d)* to treat fasciotomy wounds in two patients. NPWTi-d provides automated, volumetric control of instilled topical wound solutions with a dwell time in combination with negative pressure wound therapy (NPWT). Patient 1, a 33-year-old male injured in a motorcycle accident, developed ACS within 24 hours of hospitalization. Prior treatments included wet-to-dry dressings and NPWT†. In the latter course of treatment, NPWTi-d was applied; 40 ml of normal saline (NS) were instilled with a ten-minute dwell time, followed by four hours of NPWT at ‑125 mmHg. After five days of NPWTi‑d, granulation tissue covered the bone. Four days later, the patient was discharged home. The wound continued to improve and, at the last recorded visit, was completely closed. Patient 2, a 44-year-old male, developed right lower extremity ACS due to complications post cardiac surgery. NPWT was initiated in the hospital and continued post-discharge to a nursing home. The patient was readmitted to the hospital with a right leg wound infection that was surgically debrided. NPWTi-d was then applied; 60 ml of NS were instilled with a ten-minute dwell time, followed by 3.5 hours of NPWT at -125 mmHg. After ten days of NPWTi-d, granulation tissue covered the bone. In Patient 2, NPWTi-d improved the likelihood of healing in a malnourished patient who had been critically ill by promoting granulation tissue over exposed bone. The use of NPWTi-d with NS contributed to positive outcomes for both patients. *V

  7. Binding characteristics of 125I-labelled human FSH to granulosa cells from Booroola ewes which were homozygous, heterozygous or non-carriers of a major gene(s) influencing their ovulation rate.

    PubMed

    McNatty, K P; Lun, S; Heath, D A; Hudson, N L; O'Keeffe, L E; Henderson, K M

    1989-05-01

    At 37 degrees C 125I-labelled human (h) FSH (NIAMDD-hFSH-I-3) bound rapidly to granulosa cells from Booroola and Romney ewes with 50% maximum binding achieved after 3 min and equilibrium being reached within 45 min, irrespective of whether the cells were obtained from the FF, F+ or ++ Booroola genotypes or from Romney ewes. Binding of 125I-labelled FSH followed second order kinetics and there was no effect of follicle diameter (1-2.5 mm vs greater than or equal to 3 mm). Irrespective of breed, genotype or follicle size, the mean (+/- s.e.m.) calculated association rate constant, (ka) was 7.3 (+/- 0.8) x 10(5) litres mol-1 sec-1 (n = 12). Dissociation of receptor bound 125I-labelled hFSH was less than 5% after 30 min and low but variable (i.e. between 0 and 30%) after 2-6 h irrespective of breed, genotype or follicle size. No gene-specific differences were noted in binding specificity between F+ and ++ genotypes: studies were not performed with cells from FF ewes because of insufficient cells. The binding of 125I-labelled hFSH could be displaced with sheep FSH (NIH-FSH-S16; 10% cross-reaction) and FSH-P (2.5% cross-reaction) but other sheep pituitary hormones and hCG showed little or no cross-reaction (less than or equal to 0.1%). The calculated binding capacities (Bmax) and equilibrium dissociation constants (Kd) for 125I-labelled hFSH binding to granulosa cells did not differ between the Booroola genotypes or between Booroola or Romney follicles of different diameter (i.e. 1-2.5 mm; or greater than or equal to 3 mm). The overall mean +/- s.e.m. (n = 24) Bmax and Kd values were 16.7 +/- 0.8 fm/mg protein (i.e. approximately 800 available receptor binding sites/cell) and 1.1 +/- 0.1 nM respectively. Collectively, these findings suggest that the earlier maturation of follicles in FF or F+ ewes compared to ++ ewes is unlikely to be due to gene-specific differences in the FSH binding characteristics of the granulosa cells.

  8. In vivo Overhauser-enhanced MRI of proteolytic activity.

    PubMed

    Koonjoo, Neha; Parzy, Elodie; Massot, Philippe; Lepetit-Coiffé, Matthieu; Marque, Sylvain R A; Franconi, Jean-Michel; Thiaudiere, Eric; Mellet, Philippe

    2014-01-01

    There is an increasing interest in developing novel imaging strategies for sensing proteolytic activities in intact organisms in vivo. Overhauser-enhanced MRI (OMRI) offers the possibility to reveal the proteolysis of nitroxide-labeled macromolecules thanks to a sharp decrease of the rotational correlation time of the nitroxide moiety upon cleavage. In this paper, this concept is illustrated in vivo at 0.2 T using nitroxide-labeled elastin orally administered in mice. In vitro, this elastin derivative was OMRI-visible and gave rise to high Overhauser enhancements (19-fold at 18 mm nitroxide) upon proteolysis by pancreatic porcine elastase. In vivo three-dimensional OMRI detection of proteolysis was carried out. A keyhole fully balanced steady-state free precession sequence was used, which allowed 3D OMRI acquisition within 20 s at 0.125 mm(3) resolution. About 30 min after mouse gavage, proteolysis was detected in the duodenum, where Overhauser enhancements were 7.2 ± 2.4 (n = 7) and was not observed in the stomach. Conversely, orally administered free nitroxides or pre-digested nitroxide-labeled elastin were detected in the mouse's stomach by OMRI. Combined with specific molecular probes, this Overhauser-enhanced MRI technique can be used to evaluate unregulated proteolytic activities in various models of experimental diseases and for drug testing. Copyright © 2014 John Wiley & Sons, Ltd.

  9. [Activity of acid aspartic proteinase Candida strains isolated from palatine tonsils].

    PubMed

    Rózga, A; Jaskółowska, A; Kurnatowski, P

    2001-01-01

    We have evalueated the activity of acidous asparagine protease in 48 strains of Candida isolated from homogenates of palatine tonsils from 116 patients after tonsilectomy. Strains most frequently isolated were C. albicans (66.7 +/- 6.8%) and C. tropicalis (14.6 +/- 5.09%). The range of proteolysis zone for Candida strains was 4.6 to 12.5 mm. Over 60% of the studied strains showed high and very high proteolytic activity (>6.6 mm) and the remaining strains showed moderate activity (4.6-6.5). There were no strains with low medium activity (to 4.5 mm zone). The range of the number of rosettes E formed by lymphocytes obtained from the studied tonsils was 0-268.3. Lymphocytes isolated from 70 % of tonsils infected with Candida formed only 0-130 rosettes E; in the remaining cases the number ranged between 131 and 220. The number of lymphocytes T forming rosettes E isolated from palatine tonsils from patients not infected with fungi was 2.5 times higher. There was no correlation between the size of proteolysis zone and the number of rosettes E.

  10. Separation of fossil resin from northeast China coal

    SciTech Connect

    Xie, H.; Cao, J.; Huang, B.; Zhang, R.Z.; Xia, Q.

    1997-12-31

    Some coalfields in China contain macroscopic fossil resins. These fossil resins have not been recovered commercially. The distribution of fossil resin in coal from northeast China was characterized before recovering it by flotation and gravity separation. The fossil resin particles whose weight accounted for more than 99% of all fossil resin in the sample were larger than 0.125mm. A concentrate product that contained almost 100% fossil resin at a recovery of more than 88% was obtained from a feed containing 1.72% fossil resin using a shaking table followed by float-sink separation with a sodium chloride solution (1.1g/ml). By conventional single stage flotation, a fossil resin concentrate containing 48% fossil resin at a recovery of 95% was obtained from a feed containing 11.4% fossil resin. Adjusting the pH of the slurry with HCl or CaO before flotation did not improve the selectivity of flotation for fossil resin appreciably. Treating the feed with H{sub 2}O{sub 2} solution before flotation increased the grade of the concentrate to a certain extent, but decreased the recovery of fossil resin greatly.

  11. Haptic Perception of Edge Sharpness in Real and Virtual Environments.

    PubMed

    Park, Jaeyoung; Provancher, William; Tan, Hong Z

    2016-09-21

    We investigate the accuracy with which the haptic sharpness perception of a virtual edge is matched to that of a real edge and the effect of the virtual surface stiffness on the match. The perceived sharpness of virtual edges was estimated in terms of the point of subjective equality (PSE) when participants matched the sharpness of virtual edges to that of real edges with a radius of 0.5, 2.5 and 12.5 mm over a virtual stiffness range of 0.6 to 3.0 N/mm. The perceived sharpness of a real and a virtual edge of the same radius was significantly different under all but one of the experimental conditions and there was a significant effect of virtual surface stiffness on the accuracy of the match. The results suggest that the latter is presumably due to a constant penetration force employed by the participants that influenced the penetration depth and perceived sharpness of virtual edges at different surface stiffness levels. Our findings provide quantitative relations for appropriately offsetting the radii of virtual edges in order to achieve the desired perceived sharpness of virtual edges.

  12. Debris cloud characterization at impact velocities of 5 to 11 km/s

    SciTech Connect

    Chhabildas, L.C.; Boslough, M.B.; Reinhart, W.D.; Hall, C.A.

    1993-08-01

    A series of experiments has been performed on the Sandia HyperVelocity Launcher to impact a 1.25-mm thick aluminum bumper by an aluminum flier plate 17-mm diameter by 0.92-mm thick over the velocity range of 5 km/s to 11 km/s. Radiographic techniques were employed to record the debris cloud generated upon impact. The shape of the debris cloud is found to depend on the flier plate tilt. Generally -- the data indicate a central core of higher density surrounded by a diffused layer. These experiments allow measurements of debris cloud expansion velocities as the material undergoes a phase change from solid fragments at impact velocities of 5 km/s to a mixture of liquid and vapor phase at higher impact velocities. The expansion velocity of the debris cloud increases with increasing impact velocity, with the high-density leading edge traveling faster than the impact velocity. There is a difference between the X-ray and photographic measurements of expansion velocities at higher impact velocities. This is believed to be due to the presence of very low-density vapor in the photographic records that are not detecting using X-ray techniques.

  13. The evaluation of smaller plasterboards on productivity, work demands and workload in construction workers.

    PubMed

    van der Molen, Henk F; Mol, Eric; Kuijer, P Paul F M; Frings-Dresen, Monique H W

    2007-09-01

    Manual handling of plasterboards in order to construct interior building walls is a risk factor for musculoskeletal complaints. Unfortunately, mechanical lifting aids to reduce the physical workload are impractical for this task. Therefore, the effect of smaller plasterboards on productivity, work demands and workload was evaluated in an exploratory study among experienced construction workers (n=4-8) at the worksite. The dimensions and weight of the conventional and smaller plasterboards (PB) were: PB120 (2440 x 1200 x 15 mm; 33 kg) and PB90 (2440 x 900 x 12.5 mm; 20 kg), respectively. Productivity was defined as meters of plasterboard mounted. Work demands were assessed by means of real time observations of tasks and activities. Workload was determined using continuous heart rate monitoring and subjective judgments of perceived workload. Productivity and total work time per working day did not differ between PB120 and PB90. Duration of mounting (29% increase) and anchoring (26% increase) were longer for PB90 than PB120. Duration of lifting, carrying and turning over plasterboards, and percentage of heart rate reserve showed no difference between PB120 and PB90. A majority of the workers preferred PB90. For the last two reasons and because PB90 weighs approximately 40% less than PB120, PB90 seems preferable. The workload in both conditions, however, was considered high.

  14. Effect of negative pressure on growth, secretion and biofilm formation of Staphylococcus aureus.

    PubMed

    Li, Tongtong; Wang, Guoqi; Yin, Peng; Li, Zhirui; Zhang, Licheng; Liu, Jianheng; Li, Ming; Zhang, Lihai; Han, Li; Tang, Peifu

    2015-10-01

    Negative pressure wound therapy (NPWT) has gained popularity in the management of contaminated wounds as an effective physical therapy, although its influence on the bacteria in the wounds remains unclear. In this study, we attempted to explore the effect of negative pressure conditions on Staphylococcus aureus, the most frequently isolated pathogen during wound infection. S. aureus was cultured in Luria-Bertani medium at subatmospheric pressure of -125 mmHg for 24 h, with the bacteria grown at ambient pressure as the control. The application of negative pressure was found to slow down the growth rate and inhibit biofilm development of S. aureus, which was confirmed by static biofilm assays. Furthermore, decreases in the total amount of virulence factors and biofilm components were observed, including α-hemolysin, extracellular adherence protein, polysaccharide intercellular adhesin and extracellular DNA. With quantitative RT-PCR analysis, we also revealed a significant inhibition in the transcription of virulence and regulatory genes related to wound infections and bacterial biofilms. Together, these findings indicated that negative pressure could inhibit the growth, virulence and biofilm formation of S. aureus. A topical subatmospheric pressure condition, such as NPWT, may be a potential antivirulence and antibiofilm strategy in the field of wound care.

  15. An Efficient Method for Calculating the Characteristics of the Integrated Lens Antennas on the Basis of the Geometrical and Physical Optics Approximations

    NASA Astrophysics Data System (ADS)

    Mozharovskiy, A. V.; Artemenko, A. A.; Mal'tsev, A. A.; Maslennikov, R. O.; Sevast'yanov, A. G.; Ssorin, V. N.

    2015-11-01

    We develop a combined method for calculating the characteristics of the integrated lens antennas for millimeter-wave wireless local radio-communication systems on the basis of the geometrical and physical optics approximations. The method is based on the concepts of geometrical optics for calculating the electromagnetic-field distribution on the lens surface (with allowance for multiple internal re-reflections) and physical optics for determining the antenna-radiated fields in the Fraunhofer zone. Using the developed combined method, we study various integrated lens antennas on the basis of the data on the used-lens shape and material and the primary-feed radiation model, which is specified analytically or by computer simulation. Optimal values of the cylindrical-extension length, which ensure the maximum antenna directivity equal to 19.1 and 23.8 dBi for the greater and smaller lenses, respectively, are obtained for the hemispherical quartz-glass lenses having the cylindrical extensions with radii of 7.5 and 12.5 mm. In this case, the scanning-angle range of the considered antennas is greater than ±20° for an admissible 2-dB decrease in the directivity of the deflected beam. The calculation results obtained using the developed method are confirmed by the experimental studies performed for the prototypes of the integrated quartz-glass lens antennas within the framework of this research.

  16. A new rigid biodegradable anchor for meniscus refixation: biomechanical evaluation.

    PubMed

    Zantop, Thore; Eggers, Anne Kathleen; Musahl, Volker; Weimann, Andre; Hassenpflug, Joachim; Petersen, Wolf

    2004-07-01

    All-inside repair devices have been developed to overcome the disadvantages of conventional suture techniques (such as vein and nerve damage and increased OR time). The Contour Meniscus Arrow is a second generation of the first biodegradable all-inside implant, the Meniscus Arrow. The aim of this study was to compare the biomechanical properties of the Contour Meniscus Arrow to the first-generation Meniscus Arrow and vertical or horizontal suture techniques. In fresh frozen bovine menisci, initial fixation strength, stiffness and failure mode of four different meniscus refixation techniques (Meniscus Arrow, Contour Meniscus Arrow, vertical and horizontal 2-0 Ethibond suture techniques) were evaluated in a computer-based material-testing machine at a rate of 12.5 mm/s. Vertical meniscus sutures showed the highest initial fixation strength, followed by the horizontal suture technique and the Contour Arrow. The Meniscus Arrow showed inferior pull-out strength. Subjecting the different refixation techniques to cyclic testing decreased the fixation strength in all groups. The modified Meniscus Anchor (Contour Arrow) provides biomechanical properties that are superior (pull-out strength) or similar (stiffness) compared to the first biodegradable all-inside implant, the Meniscus Arrow. The pull-out strength of the Contour Arrow was comparable to the pull-out strength reported for horizontal meniscus sutures in the literature. These biomechanical characteristics of this new implant justify clinical use.

  17. Human motion energy harvesting: numerical analysis of electromagnetic swing-excited structures

    NASA Astrophysics Data System (ADS)

    Ylli, K.; Hoffmann, D.; Willmann, A.; Folkmer, B.; Manoli, Y.

    2016-09-01

    Energy harvesting from human motion has constantly attracted scientific interest over recent years. A location where a harvesting device can easily and unobtrusively be integrated is the shoe sole, which also protects the device from exterior influences. In this work a numerical system model is developed, which can be used to simulate different inductive harvester geometries and predict their power output. Real world acceleration data is used as a model input. The model is implemented in Matlab/Simulink and subdivided into a mechanical and an electromagnetic model. The key features including the motion model and the calculation of the electromagnetic coupling coefficient are explained in detail and the model is briefly evaluated experimentally. A total of six inductive architectures, i.e. different cylindrical and rectangular magnet-coil arrangements, are then investigated in detail. The geometrical parameters are optimized for each architecture to find the best geometry within the size of 71 mm × 37.5 mm × 12.5 mm, which can be integrated into the sole. With the best overall design an average power output of 42.7 mW is simulated across an ohmic load of 41 Ohms. In addition to the respective best designs, the (dis-)advantages of each architecture are explained.

  18. Application of nondestructive testing methods to study the damage zone underneath impact craters of MEMIN laboratory experiments

    NASA Astrophysics Data System (ADS)

    Moser, Dorothee; Poelchau, Michael H.; Stark, Florian; Grosse, Christian

    2013-01-01

    Within the framework of the Multidisciplinary Experimental and Modeling Impact Research Network (MEMIN) research group, the damage zones underneath two experimentally produced impact craters in sandstone targets were investigated using several nondestructive testing (NDT) methods. The 20 × 20 × 20 cm sandstones were impacted by steel projectiles with a radius of 1.25 mm at approximately 5 km s-1, resulting in craters with approximately 6 cm diameter and approximately 1 cm depth. Ultrasound (US) tomography and vibrational analysis were applied before and after the impact experiments to characterize the damage zone, and micro-computer tomography (μ-CT) measurements were performed to visualize subsurface fractures. The newly obtained experimental data can help to quantify the extent of the damage zone, which extends to about 8 cm depth in the target. The impacted sandstone shows a local p-wave reduction of 18% below the crater floor, and a general reduction in elastic moduli by between approximately 9 and approximately 18%, depending on the type of elastic modulus. The results contribute to a better empirical and theoretical understanding of hypervelocity events and simulations of cratering processes.

  19. Confocal Endomicroscopy: Instrumentation and Medical Applications

    PubMed Central

    Jabbour, Joey M.; Saldua, Meagan A.; Bixler, Joel N.; Maitland, Kristen C.

    2013-01-01

    Advances in fiber optic technology and miniaturized optics and mechanics have propelled confocal endomicroscopy into the clinical realm. This high resolution, non-invasive imaging technology provides the ability to microscopically evaluate cellular and sub-cellular features in tissue in vivo by optical sectioning. Because many cancers originate in epithelial tissues accessible by endoscopes, confocal endomicroscopy has been explored to detect regions of possible neoplasia at an earlier stage by imaging morphological features in vivo that are significant in histopathologic evaluation. This technique allows real-time assessment of tissue which may improve diagnostic yield by guiding biopsy. Research and development continues to reduce the overall size of the imaging probe, increase the image acquisition speed, and improve resolution and field of view of confocal endomicroscopes. Technical advances will continue to enable application to less accessible organs and more complex systems in the body. Lateral and axial resolutions down to 0.5 μm and 3 μm, respectively, field of view as large as 800×450 μm, and objective lens and total probe outer diameters down to 350 μm and 1.25 mm, respectively, have been achieved. We provide a review of the historical developments of confocal imaging in vivo, the evolution of endomicroscope instrumentation, and the medical applications of confocal endomicroscopy. PMID:21994069

  20. Pinhole SPECT of mice using the LumaGEM gamma camera

    NASA Astrophysics Data System (ADS)

    MacDonald, L. R.; Patt, B. E.; Iwanczyk, J. S.; Tsui, B. M. W.; Wang, Y.; Frey, E. C.; Wessell, D. E.; Acton, P. D.; Kung, H. F.

    2001-06-01

    LumaGEM is a newly developed gamma camera for dedicated, small field of view, high spatial resolution imaging. The system consists of an array of 2/spl times/2/spl times/6 mm/sup 3/ NaI(Tl) pixels coupled to an array of position-sensitive photomultiplier tubes. It has a 125/spl times/125 mm/sup 2/ field of view. A pinhole collimator was used on LumaGEM to acquire SPECT images of mice that had transgenic modifications so as to model various diseases. Pinhole apertures of 1, 2 and 3 mm are interchangeable on the collimator and were used to acquire images. An iterative MLEM algorithm for pinhole SPECT was used to reconstruct the 128 projection images that covered 360/spl deg/ rotation. The reconstruction algorithm is based on a projector and backprojector pair implemented using a ray-tracing algorithm. The crucial reconstruction input parameters are the radius of rotation, center of rotation, and pinhole focal length. Ideal pinhole geometry is assumed, and no correction for attenuation has been made. The preliminary images presented here show detailed uptake in the mice subjects and are a convincing sign that animal SPECT can reach submillimeter spatial resolution and be a valuable tool in the study of diseases and the development of pharmaceuticals in animal models.

  1. Calculation of electrical potentials on the surface of a realistic head model by finite differences.

    PubMed

    Lemieux, L; McBride, A; Hand, J W

    1996-07-01

    We present a method for the calculation of electrical potentials at the surface of realistic head models from a point dipole generator based on a 3D finite-difference algorithm. The model was validated by comparing calculated values with those obtained algebraically for a three-shell spherical model. For a 1.25 mm cubic grid size, the mean error was 4.9% for a superficial dipole (3.75 mm from the inner surface of the skull) pointing in the radial direction. The effect of generator discretization and node spacing on the accuracy of the model was studied. Three values of the node spacing were considered: 1, 1.25 and 1.5 mm. The mean relative errors were 4.2, 6.3 and 9.3% respectively. The quality of the approximation of a point dipole by an array of nodes in a spherical neighbourhood did not depend significantly on the number of nodes used. The application of the method to a conduction model derived from MRI data is demonstrated.

  2. The possibility of E-glass woven roving as reinforcement of GFRP composite sheet roof

    NASA Astrophysics Data System (ADS)

    Setyanto, Djoko

    2016-03-01

    The 1.25 mm thickness of opaque glass fiber reinforced polymer (GFRP) composite sheet roof that is produced by an Indonesia company at Tangerang, consists of two layers of 300 g/m2 E-glass chopped strand mat as reinforcement and unsaturated polyester resin as matrix. A layer of 300 g/m2 E-glass chopped strand mat is replaced by a layer of 400 g/m2 E-glass woven roving as reinforcement to study the possibility use as sheet roof material. The properties of the two samples of GFRP composite materials were compared. Barcol hardness and flexure strength of the two samples relatively not significance change. Tensile strength and elastic modulus of the new sample which contains a layer of woven roving reinforcement is greater than the other one. On the other hand the waviness of the new sample is greater, but cheaper. In general, a layer of E-glass woven roving and a layer of E-glass chopped strand mat can be considered as an alternative reinforcement of two layers reinforcement of GFRP composite material of sheet roof.

  3. Analysis of passivated A-286 stainless steel surfaces for mass spectrometer inlet systems by Auger electron and X-ray photoelectron spectroscopy and scanning electron microscopy

    DOE PAGES

    Ajo, Henry; Blankenship, Donnie; Clark, Elliot

    2014-07-25

    In this study, various commercially available surface treatments are being explored for use on stainless steel components in mass spectrometer inlet systems. Type A-286 stainless steel coupons, approximately 12.5 mm in diameter and 3 mm thick, were passivated with one of five different surface treatments; an untreated coupon served as a control. The surface and near-surface microstructure and chemistry of the coupons were investigated using sputter depth profiling using Auger electron spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy (SEM). All the surface treatments studied appeared to change the surface morphology dramatically, as evidenced by lack of tool marks onmore » the treated samples in SEM images. In terms of the passivation treatment, Vendors A-D appeared to have oxide layers that were very similar in thickness to each other (0.7–0.9 nm thick), as well as to the untreated samples (the untreated sample oxide layers appeared to be somewhat larger). Vendor E’s silicon coating appears to be on the order of 200 nm thick.« less

  4. The use of vacuum-assisted closure therapy for the treatment of lower-extremity wounds with exposed bone.

    PubMed

    DeFranzo, A J; Argenta, L C; Marks, M W; Molnar, J A; David, L R; Webb, L X; Ward, W G; Teasdall, R G

    2001-10-01

    Lower-extremity wounds with exposed tendon, bone, or orthopedic hardware present a difficult treatment challenge. In this series of patients, subatmospheric pressure therapy was applied to such lower-extremity wounds. Seventy-five patients with lower-extremity wounds, most of which were the result of trauma, were selected for this study. Dressings made of sterile open-cell foam with embedded fenestrated tubing were contoured to the wound size and placed into the wound. The site was covered with an adhesive plastic sheet. The sheet was placed beneath any external fixation devices, or the fixation device was enclosed within the sheet. The tubing was connected to the vacuum-assisted closure pump. Continuous subatmospheric suction pressure (125 mmHg) was applied to the wound site. The wounds were inspected and the dressings were changed every 48 hours.Vacuum-assisted closure therapy greatly reduced the amount of tissue edema, diminishing the circumference of the extremity and thus decreasing the surface area of the wound. Profuse granulation tissue formed rapidly, covering bone and hardware. The wounds were closed primarily and covered with split-thickness skin grafts, or a regional flap was rotated into the granulating bed to fill the defect. Successful coverage was obtained without complication in 71 of 75 patients. Wounds have been stable from 6 months up to 6 years.

  5. A micromachined angular-acceleration sensor for geophysical applications

    NASA Astrophysics Data System (ADS)

    Liu, Huafeng; Pike, W. T.

    2016-10-01

    This paper presents an angular-acceleration sensor that works as either an angular accelerometer or a gravity gradiometer and is based on the micro electromechanical system (MEMS) technology. The changes in the angle of the sensor mass are sensed by a rotational capacitive array transducer that is formed by electrodes on both the stator and rotor dies of the flip-chip-bonded MEMS chip (21 mm × 12.5 mm × 1 mm). The prototype was characterized, demonstrating a fundamental frequency of 27 Hz, a quality factor of 230 in air, and a sensitivity of 6 mV/(rad/s2). The demonstrated noise floor was less than 0.003 rad/s2/ √{ Hz } within a bandwidth of 0.1 Hz to 10 Hz, which is comparable with the conventional angular accelerometer and is better than the other reported MEMS sensors in low-frequency ranges. The features of small size and low cost suggest that this MEMS angular-acceleration sensor could be mounted on a drone, a satellite or even a Mars rover, and it is promising to be used for monitoring angular accelerations, aiding seismic recording, mapping gravity anomalies, and other geophysical applications for large-scale terrestrial and space deployments.

  6. Silk: Optical Properties over 12.6 Octaves THz-IR-Visible-UV Range

    PubMed Central

    Balčytis, Armandas; Ryu, Meguya; Wang, Xuewen; Novelli, Fabio; Seniutinas, Gediminas; Du, Shan; Wang, Xungai; Li, Jingliang; Davis, Jeffrey; Appadoo, Dominique; Morikawa, Junko; Juodkazis, Saulius

    2017-01-01

    Domestic (Bombyx mori) and wild (Antheraea pernyi) silk fibers were characterised over a wide spectral range from THz 8 cm−1 (λ= 1.25 mm, f= 0.24 THz) to deep-UV 50×103 cm−1 (λ= 200 nm, f= 1500 THz) wavelengths or over a 12.6 octave frequency range. Spectral features at β-sheet, α-coil and amorphous fibroin were analysed at different spectral ranges. Single fiber cross sections at mid-IR were used to determine spatial distribution of different silk constituents and revealed an α-coil rich core and more broadly spread β-sheets in natural silk fibers obtained from wild Antheraea pernyi moths. Low energy T-ray bands at 243 and 229 cm−1 were observed in crystalline fibers of domestic and wild silk fibers, respectively, and showed no spectral shift down to 78 K temperature. A distinct 20±4 cm−1 band was observed in the crystalline Antheraea pernyi silk fibers. Systematic analysis and assignment of the observed spectral bands is presented. Water solubility and biodegradability of silk, required for bio-medical and sensor applications, are directly inferred from specific spectral bands. PMID:28772716

  7. The distance between the posterior communicating arteries and their relation to the endoscopic third ventriculostomy in adults: An anatomic study

    PubMed Central

    Romero, Alicia Del Carmen Becerra; da Silva, Carlos Eduardo; de Aguiar, Paulo Henrique Pires

    2011-01-01

    Background: The diencephalic leaf of the Liliequist's membrane is a continuous structure that should be perforated in the endoscopic third ventriculostomy. Its lateral borders are penetrated by the third cranial nerve and the posterior communicating arteries. The most important complication of endoscopic third ventriculostomy is the vascular injury, such as the posterior communicating artery. The purpose of this study is to measure the distance between posterior communicating arteries located below the third ventricle floor and anterior of the mammillary bodies. Methods: In this observational prospective study 20 fresh brains from cadavers were utilized to measure the distance between the posterior communicating arteries in April 2008 at the Death Check Unit of our Institution. A digital photograph of the posterior communicating arteries was taken and the distance between the arteries was measured. The measurement was analyzed using descriptive statistics. Results: In the descriptive analysis of the 20 specimens, the posterior communicating arteries distance was 9 to 18.9 mm, a mean of 12.5 mm, median of 12.2 mm, standard deviation of 2.3 mm. Conclusion: The detailed knowledge of vascular structures involved in the endoscopic third ventriculostomy as to the posterior communicating arteries distance provides a safe lateral vascular border when performing such procedure. PMID:21748043

  8. Treatment of gingival recession using enamel matrix proteins: a case report with 4-year follow-up.

    PubMed

    Kuru, Bahar; Yilmaz, Selçuk; Noyan, Ulkü

    2007-05-01

    Obtaining predictable and optimal coverage of exposed root surfaces and correction of corresponding gingival recessions have become important goals of periodontal plastic surgery. Various surgical techniques have been proposed for coverage of root surfaces. A therapeutic advantage may be gained if periodontal regeneration is obtained in addition to coverage of root with gingiva. In this case report, surgical recession coverage was performed as the bilaterally pedicled lateral sliding flap technique with the adjunctive use of enamel matrix derivative bioactive material (Emdogain). A female patient with gingival recession on maxillary central incisors is presented with 4-year follow-up observation. The surgical procedure used in this clinical pilot case study produced a marked reduction in gingival recession that was maintained for 4 years. Initial gingival recession averaged 4.25 mm with a probing depth of 1.25 mm. The 4-year follow-up demonstrated no significant changes in the degree of postoperative results obtained after 1 year. At the 4-year follow-up, a mean of 3.75 mm of root coverage was observed (93.8% root coverage). Probing depth averaged 0.75 mm, indicating a total of 4.25 mm gain of clinical attachment. Within the limits of this case, the results demonstrated the possibility of treating human buccal recessions by means of enamel matrix protein derivative together with the laterally repositioned flap technique, with a predictable reduction in recession and clinical gain in attachment.

  9. Amorphous Ti-Zr; Base Metglas brazing filler metals

    SciTech Connect

    Rabinkin, A.; Liebermann, H.; Pounds, S.; Taylor, T. )

    1991-01-01

    This paper is the first report on processing, properties and potential application of amorphous titanium/zirconium-base alloys produced in the form of a good quality continuous and ductile ribbon having up to 12.5 mm width. To date, the majority of titanium brazing is accomplished using cooper and aluminum-base brazing filler metals. The brazements produced with these filler metals have rather low ({approximately}300{degrees} C) service temperature, thus impeding progress in aircraft and other technologies and industries. The attempt to develop a generation of high temperature brazing filler metals was made in the late sixties-early seventies studies in detail were a large number of Ti-, Zr-Ti-Zr, Ti-V and Zr-V-Ti based alloys. The majority of these alloys has copper and nickel as melting temperature depressants. The presence of nickel and copper converts them into eutectic alloys having (Ti(Zr)) (Cu(Ni)), intermetallic phases as major structural constituents. This, in turn, results in high alloy brittleness and poor, if any, processability by means of conventional, i.e. melting-ingot casting-deformation technology. In spite of good wettability and high joint strength achieved in dozens of promising alloys, only Ti-15Cu-15Ni is now widely used as a brazing filler metal for high service temperature. Up until now this material could not be produced as a homogeneous foil and is instead applied as a clad strip consisting of three separate metallic layers.

  10. The design of Cu-doped ZnO thermoelectric module (simulation study)

    NASA Astrophysics Data System (ADS)

    Hadi, Syamsul; Suratwan, Agus; Kurniawan, Agus; Budiana, Eko Prasetya; Suyitno

    2016-03-01

    The p-type semiconductor of Cu-doped ZnO-based thermoelectric material has already been synthesized and studied as an energy harvester. The next challenge is manufacturing the thermoelectric module in the development of thermoelectric as an eco-friendly material in the future. This research aims to investigate the effect of thermoelectric geometric design on the electrical output power and voltage and to recommend the most appropriate thermoelectric geometric design. The design of thermoelectric generator (TEG) includes the determinations of dimension (width, length, and height), number of modules, and semiconductor materials. The simulation used the coupled-field analysis of ANSYS APDL 14.5 in the steady state condition. The p- and n- type thermoelectric material used Cu-doped ZnO and Al-doped ZnO, respectively. The width of element and the number of thermoelectric module were varied to obtain a thermoelectric design, which produces the largest current, power, and voltage. The result of research shows that the t hermoelectric generator with the element widths of 0.94 mm, 1.125 mm, 1.05 mm, and 1.2 mm generates the largest power output and voltage, namely: 0.32 W and 0.89 V, 0.38 W and 0.98 V, 0.45 W and 1.06 V, and 0.52 W and 1.13 V, respectively.

  11. Intensity of Rainfall and Severity of Melioidosis, Australia

    PubMed Central

    Jacups, Susan P.

    2003-01-01

    In a 12-year prospective study of 318 culture-confirmed cases of melioidosis from the Top End of the Northern Territory of Australia, rainfall data for individual patient locations were correlated with patient risk factors, clinical parameters, and outcomes. Median rainfall in the 14 days before admission was highest for those dying with melioidosis (211 mm), in comparison to 110 mm for those surviving (p = 0.0002). Median 14-day rainfall was also significantly higher for those admitted with pneumonia. On univariate analysis, a prior 14-day rainfall of ≥125 mm was significantly correlated with pneumonia (odds ratio [OR] 1.70 [confidence interval [CI] 1.09 to 2.65]), bacteremia (OR 1.93 [CI 1.24 to 3.02]), septic shock (OR 1.94 [CI 1.14 to 3.29]), and death (OR 2.50 [CI 1.36 to 4.57]). On multivariate analysis, rainfall in the 14 days before admission was an independent risk factor for pneumonia (p = 0.023), bacteremic pneumonia (p = 0.001), septic shock (p = 0.005), and death (p < 0.0001). Heavy monsoonal rains and winds may cause a shift towards inhalation of Burkholderia pseudomallei. PMID:14720392

  12. Detection of vascular injuries in patients with blunt pelvic trauma by using 64-channel multidetector CT.

    PubMed

    Kertesz, Jennifer L; Anderson, Stephan W; Murakami, Akira M; Pieroni, Sabrina; Rhea, James T; Soto, Jorge A

    2009-01-01

    Vascular injuries are a major source of morbidity and mortality in patients with blunt pelvic trauma. Digital subtraction angiography (DSA) has traditionally been used to detect pelvic arterial injuries and to treat active arterial hemorrhage. Improvements in the technology of computed tomography (CT) have facilitated the implementation of CT angiography, which is beginning to replace DSA in the evaluation of patients with acute trauma. Pelvic CT angiography can reliably depict various pelvic arterial injuries and can help differentiate arterial hemorrhage from venous hemorrhage on the basis of multiphasic acquisitions, a method that may be used to tailor the subsequent clinical approach. With the use of a 64-channel multidetector CT scanner, multiphasic pelvic CT angiography can be integrated into the evaluation of trauma patients by using 1.25-mm reconstructed section thickness, pitch of 1:0.987, and gantry revolution time of 0.5 second to achieve near-isotropic results. A standard dose of 100 mL intravenous contrast material is injected at a rate of 5 mL/sec, and 30 mL saline solution, also at 5 mL/sec, is injected as a "chasing" bolus to follow the contrast material. (c) RSNA, 2009.

  13. Low cost corrosion damage mitigation and improved fatigue performance of low plasticity burnished 7075-T6

    NASA Astrophysics Data System (ADS)

    Prevéy, Paul S.; Cammett, John

    2001-10-01

    Low plasticity burnishing (LPB) has been investigated as a surface enhancement process and corrosion mitigation method for aging aircraft structural applications. Compressive residual stresses reaching the alloy yield strength and extending to a depth of 1.25 mm (0.050 in.) deeper than typical corrosion damage is achievable. Excellent surface finish can be achieved with no detectable metallurgical damage to surface and subsurface material. Salt fog exposures of 100 and 500 h reduced the fatigue strength at 2×106 cycles by 50%. The LPB of the corroded surface, without removal of the corrosion product or pitted material, restored the 2×106 fatigue strength to greater than that of the original machined surface. The fatigue strength of the corroded material in the finite life regime (104 to 106 cycles) after LPB was 140 MPa (20 ksi) higher than the original uncorroded alloy and increased the life by an order of magnitude. Ease of adaptation to computer numerical control (CNC) machine tools allows LPB processing at costs and speeds comparable to machining operations. Low plasticity burnishing offers a promising new technology for mitigation of corrosion damage and improved fatigue life of aircraft structural components with significant cost and time savings over current practices.

  14. The expression of endogenous hydrogen sulfide signal during distraction osteogenesis in a rabbit model.

    PubMed

    Jiang, X-W; Zhang, Y; Cheng, Y-Z; Fan, X-S; Deng, X; Peng, H-Y

    2017-08-14

    The hydrogen sulfide (H2S) signal system plays an important role in bone metabolism. However, the role of endogenous H2S during distraction osteogenesis (DO) remains unclear. Sixty-two male New Zealand White rabbits were subjected to right mandibular DO. Before distraction, the animals were divided randomly into two groups: group A, 0.5mm twice/day for 10 days; group B, 1.25mm twice/day for 4 days. Plasma and distraction gap tissue were harvested to determine the H2S signal. The osteogenesis effect was also evaluated. The newly regenerated bone in group A presented a higher level of mineralization and biomechanical strength than that in group B. The bone mineralization density in group A was 1.95-fold that in group B (P=0.028), while the biomechanical strength in group A was 1.26-fold that in group B (P=0.042) at the end of the experiment. The H2S signal was detected during the whole process of DO. The relative plasma H2S concentrations in group A were noticeably higher than those in group B at the middle of distraction (P<0.001), at the end of the distraction (P=0.034), and 2 weeks after the end of distraction (P=0.002). The results suggest that the endogenous H2S signal system plays a major role during DO. Copyright © 2017. Published by Elsevier Ltd.

  15. Uniformity optimization and dynamic studies of plasma jet array interaction in argon

    NASA Astrophysics Data System (ADS)

    Wang, Ruixue; Sun, Hao; Zhu, Weidong; Zhang, Cheng; Zhang, Shuai; Shao, Tao

    2017-09-01

    In this paper, the uniformity of a microsecond pulse driven argon plasma jet array is studied by optimizing experimental parameters, such as the ground electrode position d, gas flow rate, and pulse frequency. The results show that when d is less than 10 mm, there are always two plasma jets that cannot be ignited; while all jets are ignited with equal length at d = 12.5 mm. The plasma jet transition from laminar to turbulent at 6 l/min, presenting a "bead-like" structure. The jet length increases with the pulse repetition frequency and reaches a plateau at around 1.5 kHz. The ICCD images show that the plasma jets emerged preferably from the two quartz tubings located at the two ends of the linear array. The spatial-temporal resolved spectra show that the Ar emission (763.5 nm) and N2 emission (337.1 nm) at the end of the array (e.g., Jet #1) appeared earlier than that of the jet in the middle (e.g., Jet #2). On the contrary, the emission intensities of Ar in Jet #2 are higher than in Jet #1. This is due to the higher electric field and air diffusion at the plasma array boundary.

  16. A Fisheries Evaluation of the Dryden Fish Screening Facility : Annual Report 1994.

    SciTech Connect

    Mueller, Robert P.; Abernethy, C.Scott; Neitzel, Duane A.

    1995-04-01

    Effectivness was evaluated of the Dryden Fish Screening Facility in the Wenatchee Reclamation District Canal near Dryden in north central Washington State. In situ tests were conducted by releasing groups of hatchery reared salmonids of different ages and sizes. Spring chinook salmon smolts (110-165 mm) were not injured or descaled in passing through the canal forebay. Smolts were not delayed as they migrated in the canal. Most fish released at the canal headworks exited the screening facility in <4 h, with >99% of the test fish captured in the fish bypass in <24 h. Steelhead subyearlings 65-125 mm were not injured or descaled in traveling through the bypass flume and fish return pipe. Average time for steelhead subyearlings to travel through thebypass structure was 70 seconds. Small rainbow trout fry 23-27mm could pass through the 0.125-in. profile bar screen openings and were entrained in the irrigation canal; about 38% was lost to the canal within 48 h of release. Some fry stayed in the forebay and did not migrate during the tests. Wild chinook fry 36-42mm were also entrained. Estimated 34% of emergent wild chinook salmon fry passed through the profile bar screens and were entrained in the canal. Approach velocity at the Dryden screens was {ge}0.4 ft/s; low velocities through the first two screen panels indicated that vertical louvers installed behind each screen panel to balance flow were not totally effective.

  17. Anisotropic Conductivity Tensor Imaging of In Vivo Canine Brain Using DT-MREIT.

    PubMed

    Jeong, Woo Chul; Sajib, Saurav Z K; Katoch, Nitish; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2017-01-01

    We present in vivo images of anisotropic electrical conductivity tensor distributions inside canine brains using diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT). The conductivity tensor is represented as a product of an ion mobility tensor and a scale factor of ion concentrations. Incorporating directional mobility information from water diffusion tensors, we developed a stable process to reconstruct anisotropic conductivity tensor images from measured magnetic flux density data using an MRI scanner. Devising a new image reconstruction algorithm, we reconstructed anisotropic conductivity tensor images of two canine brains with a pixel size of 1.25 mm. Though the reconstructed conductivity values matched well in general with those measured by using invasive probing methods, there were some discrepancies as well. The degree of white matter anisotropy was 2 to 4.5, which is smaller than previous findings of 5 to 10. The reconstructed conductivity value of the cerebrospinal fluid was about 1.3 S/m, which is smaller than previous measurements of about 1.8 S/m. Future studies of in vivo imaging experiments with disease models should follow this initial trial to validate clinical significance of DT-MREIT as a new diagnostic imaging modality. Applications in modeling and simulation studies of bioelectromagnetic phenomena including source imaging and electrical stimulation are also promising.

  18. Effects of red wine on 24-hour esophageal pH and pressures in healthy volunteers.

    PubMed

    Grande, L; Manterola, C; Ros, E; Lacima, G; Pera, C

    1997-06-01

    The purpose of this study was to assess the effects of red wine taken with meals on esophageal motility, esophageal exposure to acid, and gastric pH. Following a randomized design, 14 healthy male volunteers (mean age 25 years, range 18-35 years were given 360 ml of red wine or tap water during lunch or dinner. All subjects underwent ambulatory 24-hr esophageal motility and esophagogastric pH monitoring studies. Three different periods were analyzed: during meals (30 min), postprandial (3 hr), and 8-hr supine. Two volunteers complained of heartburn after wine ingestion. An increase in the number of high amplitude waves (> 125 mm Hg, 95th percentile of our motility unit controls) was observed during meals accompanied by wine: water 1.2 (0-10.2), wine 1.6 (0-32.6), P = 0.02 [median (range)]. No other esophageal motility changes occurred. Percent reflux time increased during the postprandial period after wine ingestion in comparison with water: 1.7 (0-14.9) vs 0.1 (0-0.8), P < 0.05. Gastric pH was unaffected by the type of drink. Ingestion of moderate amounts of red wine with meals increases postprandial esophageal exposure to gastric acid in healthy persons.

  19. Deep Orbital Dermoid Cyst Bulging into the Superior Orbital Fissure: Clinical Presentation and Management

    PubMed Central

    Kumar, Ravinder; Vyas, Kapil; Jaiswal, Gagan; Bhargava, Abhishek; Kundu, Jyoti

    2017-01-01

    Purpose: To present a case of deep orbital dermoid cyst with emphasis on clinical presentation, imaging spectrum, differential diagnosis and management. Case Report: A 28-year-old female was referred to our hospital with chief complaint of drooping of right eyelid and progressive headache. Ocular motility, visual acuity and fundus examination were normal. computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well-defined, intraosseous deep orbital dermoid cyst (5.9 mm × 12.5 mm) located near the apex of right orbit, extending from greater wing of sphenoid into the superior orbital fissure. Due to occulomotor nerve (superior and inferior divisions) compression which passes through the superior orbital fissure, ipsilateral headache and ptosis occurred. Complete surgical excision of cyst was performed using noninvasive extracranial lateral orbitotomy approach. After removal of the cyst, curette and cutting drill were used to thoroughly remove any residual cystic content. Histopathological analysis confirmed the diagnosis. The healing was uneventful postoperatively. Conclusion: CT and MRI are easy, reliable, safe and effective imaging methods for establishing the diagnosis of orbital dermoid cyst. Size, location and manifestations are the most important determinants of the disease management. Complete surgical excision without rupture of the cyst is the treatment of choice. PMID:28299014

  20. The lumbosacral nerves in relation to dorsal S1 screw placement and their locations on plain radiographs.

    PubMed

    Ebraheim, N A; Haman, S P; Xu, R; Stanescu, S; Yeasting, R A

    2000-03-01

    Seven adult cadaver lumbopelvises were harvested to study the anatomic relationship of the L4 and L5 nerves to S1 dorsal screw placement and the location of the L4, L5, and S1 nerves on plain radiographs. The mean lateral angle of S1 screw trajectory toward the L4 nerve was 31+/-8 degrees, and the mean screw trajectory length was 53+/-8 mm. The mean lateral angle of the screw trajectory toward the L5 nerve was 21+/-8 degrees, and the mean screw trajectory length was 38+/-4 mm. On both inlet and outlet radiographs, the lateral angle of the nerves increased from L4 to S1. The L4 nerve coursed over the middle third of the superior ala in the inlet view and the middle third of the lateral mass in the outlet view. The L5 nerve coursed over the inner third of the superior ala and inner third of the lateral mass. On the lateral view, the mean distances from the sacral promontory to the L4, L5, and S1 nerves along the anterior border of the sacrum were 4+/-7 mm, 12+/-5 mm, and 28+/-8 mm, respectively. This study suggests that S1 sacral screws be directed between 30 degrees and 40 degrees lateral to avoid compromising the lumbosacral trunk and sacroiliac joint.

  1. Hard-X and gamma-ray imaging detector for astrophysics based on pixelated CdTe semiconductors

    NASA Astrophysics Data System (ADS)

    Gálvez, J.-L.; Hernanz, M.; Álvarez, L.; Artigues, B.; Ullán, M.; Lozano, M.; Pellegrini, G.; Cabruja, E.; Martínez, R.; Chmeissani, M.; Puigdengoles, C.

    2016-01-01

    Stellar explosions are astrophysical phenomena of great importance and interest. Instruments with high sensitivities are essential to perform detailed studies of cosmic explosions and cosmic accelerators. In order to achieve the needed performance, a hard-X and gamma-ray imaging detector with mm spatial resolution and large enough efficiency is required. We present a detector module which consists of a single CdTe crystal of 12.5 × 12.5mm 2 and 2mm thick with a planar cathode and with the anode segmented in an 11x11 pixel array with a pixel pitch of 1 mm attached to the readout chip. Two possible detector module configurations are considered: the so-called Planar Transverse Field (PTF) and the Parallel Planar Field (PPF). The combination of several modules in PTF or PPF configuration will achieve the desired performance of the imaging detector. The sum energy resolution of all pixels of the CdTe module measured at 122 keV and 356 keV is 3.8% and 2% respectively, in the following operating conditions: PPF irradiation, bias voltage -500 V and temperature -10̂ C.

  2. Optimizing probe design for an implantable perfusion and oxygenation sensor

    SciTech Connect

    Akl, Tony; Long, Ruiqi; McShane, Michael J.; Ericson, Milton Nance; Wilson, Mark A.; Cote, Gerard L.

    2011-01-01

    In an effort to develop an implantable optical perfusion and oxygenation sensor, based on multiwavelength reflectance pulse oximetry, we investigate the effect of source detector separation and other source-detector characteristics to optimize the sensor s signal to background ratio using Monte Carlo (MC) based simulations and in vitro phantom studies. Separations in the range 0.45 to 1.25 mm were found to be optimal in the case of a point source. The numerical aperture (NA) of the source had no effect on the collected signal while the widening of the source spatial profile caused a shift in the optimal source-detector separation. Specifically, for a 4.5 mm flat beam and a 2.4 mm 2.5 mm photodetector, the optimal performance was found to be when the source and detector are adjacent to each other. These modeling results were confirmed by data collected from in vitro experiments on a liver phantom perfused with dye solutions mimicking the absorption properties of hemoglobin for different oxygenation states.

  3. Post-irradiation Examination of the AGR-1 Experiment: Plans and Preliminary Results

    SciTech Connect

    Paul Demkowicz

    2001-10-01

    Abstract – The AGR-1 irradiation experiment contains seventy-two individual cylindrical fuel compacts (25 mm long x 12.5 mm diameter) each containing approximately 4100 TRISO-coated uranium oxycarbide fuel particles. The experiment accumulated 620 effective full power days in the Advanced Test Reactor at the Idaho National Laboratory with peak burnups exceeding 19% FIMA. An extensive post-irradiation examination campaign will be performed on the AGR-1 fuel in order to characterize the irradiated fuel properties, assess the in-pile fuel performance in terms of coating integrity and fission metals release, and determine the fission product retention behavior during high temperature accident testing. PIE experiments will include dimensional measurements of fuel and irradiated graphite, burnup measurements, assessment of fission metals release during irradiation, evaluation of coating integrity using the leach-burn-leach technique, microscopic examination of kernel and coating microstructures, and accident testing of the fuel in helium at temperatures up to 1800°C. Activities completed to date include opening of the irradiated capsules, measurement of fuel dimensions, and gamma spectrometry of selected fuel compacts.

  4. ANTHROPOMORPHIC PHANTOMS FOR ASSESSMENT OF STRAIN IMAGING METHODS INVOLVING SALINE-INFUSED SONOHYSTEROGRAPHY

    PubMed Central

    Hobson, Maritza A.; Madsen, Ernest L.; Frank, Gary R.; Jiang, Jingfeng; Shi, Hairong; Hall, Timothy J.; Varghese, Tomy

    2008-01-01

    Two anthropomorphic uterine phantoms were developed which allow assessment and comparison of strain imaging systems adapted for use with saline-infused sonohysterography (SIS). Tissue-mimicking (TM) materials consist of dispersions of safflower oil in gelatin. TM fibroids are stiffer than the TM myometrium/cervix and TM polyps are softer. The first uterine phantom has 3-mm diameter TM fibroids randomly distributed in TM myometrium. The second uterine phantom has a 5-mm and an 8-mm spherical TM fibroid in addition to a 5-mm spherical and a 12.5-mm long (medicine-capsule-shaped) TM endometrial polyp protruding into the endometrial cavity; also, a 10-mm spherical TM fibroid projects from the serosal surface. Strain images using the first phantom show the stiffer 3-mm TM fibroids in the myometrium. Results from the second uterine phantom show that, as expected, parts of inclusions projecting into the uterine cavity will appear very stiff, whether they are stiff or soft. Results from both phantoms show that even though there is a five-fold difference in the Young’s moduli values, there is not a significant difference in the strain in the transition from the TM myometrium to the TM fat. These phantoms allow for realistic comparison and evolution of SIS strain imaging techniques and can aid clinical personnel to develop skills for SIS strain imaging. PMID:18514999

  5. Optimal egg size in a suboptimal environment: reproductive ecology of female Sonora mud turtles (Kinosternon sonoriense) in central Arizona, USA

    USGS Publications Warehouse

    Lovich, Jeffrey E.; Madrak, Sheila V.; Drost, Charles A.; Monatesti, Anthony J.; Casper, Dennis; Znari, Mohammed

    2012-01-01

    We studied the reproductive ecology of female Sonora mud turtles (Kinosternon sonoriense) at Montezuma Well, a chemically-challenging natural wetland in central Arizona, USA. Females matured between 115.5 and 125 mm carapace length (CL) and 36-54% produced eggs each year. Eggs were detected in X-radiographs from 23 April-28 September (2007-2008) and the highest proportion (56%) of adult females with eggs occurred in June and July. Clutch frequency was rarely more than once per year. Clutch size was weakly correlated with body size, ranged from 1-8 (mean = 4.96) and did not differ significantly between years. X-ray egg width ranged from 17.8-21.7 mm (mean 19.4 mm) and varied more among clutches than within. Mean X-ray egg width of a clutch did not vary significantly with CL of females, although X-ray pelvic aperture width increased with CL. We observed no evidence of a morphological constraint on egg width. In addition, greater variation in clutch size, relative to egg width, suggests that egg size is optimized in this hydrologically stable but chemically-challenging habitat. We suggest that the diversity of architectures exhibited by the turtle pelvis, and their associated lack of correspondence to taxonomic or behavioral groupings, explains some of the variation observed in egg size of turtles.

  6. Development of a liquid chromatographic method for the simultaneous quantification of curcumin, β-arteether, tetrahydrocurcumin and dihydroartemisinin. Application to lipid-based formulations.

    PubMed

    Memvanga, Patrick B; Mbinze, Jérémie K; Rozet, Eric; Hubert, Philippe; Préat, Véronique; Marini, Roland D

    2014-01-01

    A liquid chromatographic method was developed for the simultaneous separation of curcumin, β-arteether, tetrahydrocurcumin and dihydroartemisinin based on the design of experiments and the design space methodology. The influence of the percentage of organic modifier, flow rate of the mobile phase and column temperature on the analytes separation was investigated. The optimal chromatographic separation was achieved on a C18 column (125mm×4mm, 5μm) using an isocratic elution with a mobile phase consisting of methanol-ammonium acetate (pH 4; 10mM) (80:20, v/v) at a flow rate of 0.45ml/min and a column temperature of 32.5°C. This method was then validated for simultaneous quantification of curcumin and β-arteether contained in lipid-based formulations taking into account the β-expectation tolerance interval for the total error measurement. Finally, the suitability of the proposed liquid chromatographic method for routine analysis of curcumin and β-arteether loaded in lipid-based formulations has been proven.

  7. Gunshot injury of the foot: treatment and procedures--a role of negative pressure wound therapy.

    PubMed

    Marinović, Marin; Radović, Endi; Bakota, Bore; Mikacević, Marijan; Grzalja, Nikola; Ekl, Darko; Cepić, Ivica

    2013-04-01

    Civilian gunshot injuries of the foot are not so common in Croatia. They are related with accidents in hunting or weapon cleaning. Gunshot injuries represent a special challenge for surgeon because of specific anatomical relations and biomechanical function of the foot. We have decided to present a patient with a complex foot injury caused by hunting firearm in self-inflicted accident. A 45-year-old male presented with 12-gauge shotgun wound to his left foot. We found a complicated fracture with bone defect of 3rd, 4th and 5th metatarsals and wide soft tissue injury with skin and subcutaneous defect of the dorsal and lateral side of the foot. The wound was contaminated with numerous metal fragments, particles of rocks and ground. Surgical treatment was performed three hours after trauma and included extensive debridement of damaged soft tissue, removing of the non-viable bone and metal fragments, rocks and other foreign bodies. Negative Pressure Wound Therapy (NPWT) was applicated in the operating table. The starting therapy was continuously -125 mm Hg of vacuum. We continued with intermittent therapy of -100 mm Hg and change NPWT dressing every fourth day. After four weeks of NPWT the defect was filled with granulation tissue and split thickness skin graft was applied. Skin graft was additionally fixed with NPWT using continuous therapy at -100 mm Hg for a period of four days. Forthy days after injury there was a complete healing of all soft tissue. Control X-ray showed good bone healing process.

  8. A probabilistic atlas of the cerebellar white matter.

    PubMed

    van Baarsen, K M; Kleinnijenhuis, M; Jbabdi, S; Sotiropoulos, S N; Grotenhuis, J A; van Cappellen van Walsum, A M

    2016-01-01

    Imaging of the cerebellar cortex, deep cerebellar nuclei and their connectivity are gaining attraction, due to the important role the cerebellum plays in cognition and motor control. Atlases of the cerebellar cortex and nuclei are used to locate regions of interest in clinical and neuroscience studies. However, the white matter that connects these relay stations is of at least similar functional importance. Damage to these cerebellar white matter tracts may lead to serious language, cognitive and emotional disturbances, although the pathophysiological mechanism behind it is still debated. Differences in white matter integrity between patients and controls might shed light on structure-function correlations. A probabilistic parcellation atlas of the cerebellar white matter would help these studies by facilitating automatic segmentation of the cerebellar peduncles, the localization of lesions and the comparison of white matter integrity between patients and controls. In this work a digital three-dimensional probabilistic atlas of the cerebellar white matter is presented, based on high quality 3T, 1.25mm resolution diffusion MRI data from 90 subjects participating in the Human Connectome Project. The white matter tracts were estimated using probabilistic tractography. Results over 90 subjects were symmetrical and trajectories of superior, middle and inferior cerebellar peduncles resembled the anatomy as known from anatomical studies. This atlas will contribute to a better understanding of cerebellar white matter architecture. It may eventually aid in defining structure-function correlations in patients with cerebellar disorders.

  9. In vivo high-resolution diffusion tensor imaging of the mouse brain

    PubMed Central

    Wu, Dan; Xu, Jiadi; McMahon, Michael T.; van Zijl, Peter C.M.; Mori, Susumu; Northington, Frances, J.; Zhang, Jiangyang

    2013-01-01

    Diffusion tensor imaging (DTI) of the laboratory mouse brain provides important macroscopic information for anatomical characterization of mouse models in basic research. Currently, in vivo DTI of the mouse brain is often limited by the available resolution. In this study, we demonstrate in vivo high-resolution DTI of the mouse brain using a cryogenic probe and a modified diffusion-weighted gradient and spin echo (GRASE) imaging sequence at 11.7 Tesla. Three-dimensional (3D) DTI of the entire mouse brain at 0.125 mm isotropic resolution could be obtained in approximately two hours. The high spatial resolution, which was previously only available with ex vivo imaging, enabled non-invasive examination of small structures in the adult and neonatal mouse brains. Based on data acquired from eight adult mice, a group-averaged DTI atlas of the in vivo adult mouse brain with 60 structure segmentations was developed. Comparisons between in vivo and ex vivo mouse brain DTI data showed significant differences in brain morphology and tissue contrasts, which indicate the importance of the in vivo DTI based mouse brain atlas. PMID:23769916

  10. Experimental investigation on chill-down process of cryogenic flow line

    NASA Astrophysics Data System (ADS)

    Jin, Lingxue; Park, Changgi; Cho, Hyokjin; Lee, Cheonkyu; Jeong, Sangkwon

    2016-10-01

    This paper describes the cryogenic chill-down experiments that are conducted on a 12.7 mm outer diameter, 1.25 mm wall thickness and 7 m long stainless steel horizontal pipe with liquid nitrogen (LN2). The pipe is vacuum insulated during the experiment to minimize the heat leak from room temperature and to enable one to numerically simulate the process easily. The temperature and the pressure profiles of the chill-down line are obtained at the location which is 5.5 m in a distance from the pipe inlet. The mass flux range is approximately from 19 kg/m2 s to 49 kg/m2 s, which corresponds to the Reynolds numbers range from 1469 to 5240. The transient histories of temperature, pressure and mass flow rate during the line chill-down process are monitored, and the heat transfer coefficient and the heat flux are computed by an inverse problem solving method. The amplitude of the pressure oscillation and the oscillating period become larger and longer at higher pressure conditions. In the low mass flux conditions, the critical heat flux in horizontal pipes is not sensitive to mass flux, and is higher than that in vertical pipes. Kutateladze's correlation with the constant coefficient, B = 0.029 , well matches the experimental data in the current work. In nucleate flow boiling regime, heat transfer coefficient, h , is proportional to (q″)n , and n is equal to 0.7.

  11. Optical properties of neonatal skin measured in vivo as a function of age and skin pigmentation

    NASA Astrophysics Data System (ADS)

    Bosschaart, Nienke; Mentink, Rosaline; Kok, Joke H.; van Leeuwen, Ton G.; Aalders, Maurice C. G.

    2011-09-01

    Knowledge of the optical properties of neonatal skin is invaluable when developing new, or improving existing optical techniques for use at the neonatal intensive care. In this article, we present in vivo measurements of the absorption μa and reduced scattering coefficient μs' of neonatal skin between 450 and 600 nm and assess the influence of age and skin pigmentation on the optical properties. The optical properties were measured using a spatially resolved, steady state diffuse reflectance spectroscopy setup, combined with a modified spatially resolved diffusion model. The method was validated on phantoms with known values for the absorption and reduced scattering coefficient. Values of μa and μs' were obtained from the skin at four different body locations (forehead, sternum, hand, and foot) of 60 neonates with varying gestational age, postnatal age, and skin pigmentation. We found that μa ranged from 0.02 to 1.25 mm-1 and μs' was in the range of 1 to 2.8 mm-1 (5th to 95th percentile of the patient population), independent of body location. In contrast to previous studies, no to very weak correlation was observed between the optical properties and gestational maturity, but a strong dependency of the absorption coefficient on postnatal age was found for dark skinned patients.

  12. The effect of negative pressure wound therapy with periodic instillation using antimicrobial solutions on Pseudomonas aeruginosa biofilm on porcine skin explants.

    PubMed

    Phillips, Priscilla L; Yang, Qingping; Schultz, Gregory S

    2013-12-01

    Negative pressure wound therapy with instillation (NPWTi) is increasingly used as an adjunct therapy for a wide variety of infected wounds. However, the effect of NPWTi on mature biofilm in wounds has not been determined. This study assessed the effects of NPWTi using saline or various antimicrobial solutions on mature Pseudomonas aeruginosa biofilm using an ex vivo porcine skin explant biofilm model. Treatment consisted of six cycles with 10-minute exposure to instillation solution followed by 4 hours of negative pressure at -125 mm Hg over a 24-hour period. NPWTi using saline reduced bacterial levels by 1-log (logarithmic) of 7-log total colony-forming units (CFUs). In contrast, instillation of 1% povidone iodine (2-log), L-solution (3-log), 0·05% chlorhexidine gluconate (3-log), 0·1% polyhexamethylene biguanide (4-log), 0·2% polydiallyldimethylammonium chloride (4-log) and 10% povidone iodine (5-log), all significantly reduced (P < 0·001) total CFUs. Scanning electron micrographs showed disrupted exopolymeric matrix of biofilms and damaged bacterial cells that correlated with CFU levels. Compared with previous studies assessing microbicidal effects of topical antimicrobial dressings on biofilms cultured on porcine skin explants, these ex vivo model data suggest that NPWTi with delivery of active antimicrobial agents enhances the reduction of CFUs by increasing destruction and removal of biofilm bacteria. These results must be confirmed in human studies. © 2013 The Authors. International Wound Journal © 2013 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

  13. IRAS 21391 + 5802 - A study in intermediate mass star formation

    NASA Technical Reports Server (NTRS)

    Wilking, Bruce; Mundy, Lee; Mcmullin, Joseph; Hezel, Thomas; Keene, Jocelyn

    1993-01-01

    We present infrared and millimeter wavelength observations of the cold IRAS source 21391 + 5802 and its associated molecular core. Infrared observations at lambda = 3.5 microns reveal a heavily obscured, central point source which is coincident with a compact lambda = 2.7 mm continuum and C18O emission region. The source radiates about 310 solar luminosities, primarily at FIR wavelengths, suggesting that it is a young stellar object of intermediate mass. The steeply rising spectral energy distribution and the large fraction of the system mass residing in circumstellar material imply that IRAS 21391 + 5802 is in an early stage of evolution. The inferred dust temperature indicates a temperature gradient in the core. A comprehensive model for the surrounding core of dust and gas is devised to match the observed dust continuum emission and multitransition CS emission from this and previous studies. We find a r exp -1.5 +/- 0.2 density gradient consistent with that of a gravitationally evolved core and a total core mass of 380 solar masses. The observed dust emission is most consistent with a lambda exp -1.5 - lambda exp -2 dust emissivity law; for a lambda exp -2 law, the data are best fit by a mass opacity coefficient of 3.6 x 10 exp -3 sq cm/g at lambda = 1.25 mm.

  14. High bacterial load in negative pressure wound therapy (NPWT) foams used in the treatment of chronic wounds.

    PubMed

    Yusuf, Erlangga; Jordan, Xavier; Clauss, Martin; Borens, Olivier; Mäder, Mark; Trampuz, Andrej

    2013-01-01

    No earlier study has investigated the microbiology of negative pressure wound therapy (NPWT) foam using a standardized manner. The purpose of this study is to investigate the bacterial load and microbiological dynamics in NPWT foam removed from chronic wounds (>3 months). To determine the bacterial load, a standardized size of the removed NPWT foam was sonicated. The resulting sonication fluid was cultured, and the colony-forming units (CFU) of each species were enumerated. Sixty-eight foams from 17 patients (mean age 63 years, 71% males) were investigated. In 65 (97%) foams, ≥ 1 and in 37 (54%) ≥ 2 bacterial types were found. The bacterial load remained high during NPWT treatment, ranging from 10(4) to 10(6) CFU/ml. In three patients (27%), additional type of bacteria was found in subsequent foam cultures. The mean bacterial count ± standard deviation was higher in polyvinyl alcohol foam (6.1 ± 0.5 CFU/ml) than in polyurethane (5.5 ± 0.8 CFU/ml) (p = 0.02). The mean of log of sum of CFU/ml in foam from 125 mmHg (5.5 ± 0.8) was lower than in foam from 100 mmHg pressure (5.9 ± 0.5) (p = 0.01). Concluding, bacterial load remains high in NPWT foam, and routine changing does not reduce the load.

  15. Comparison of objects detection capabilities in LWIR and THz ranges

    NASA Astrophysics Data System (ADS)

    Kowalski, Marcin; Kastek, Mariusz; Szustakowski, Mieczyslaw

    2015-10-01

    Multispectral systems for detection of concealed dangerous objects are becoming more popular because of their higher effectiveness compared to mono-spectral systems. So far, the problem of detecting objects hidden under clothing was considered only in the case of airports but it is becoming more important for public places like metro stations, and government buildings. Exploration of new spectral bands as well as development of technology result in introduction of new solutions - both mono and multispectral. It has been proved that objects hidden under clothing can be detected and visualized using terahertz (THz) cameras. However, passive THz cameras still offer too low image resolution for objects recognition. Limited range is another issue of passive imagers. On the other hand new infrared cameras offer sufficient parameters to detect objects covered with fabrics in some conditions, as well as high image quality and big pixel resolutions. The purpose of the studies is to investigate and compare the possibilities of using passive cameras operating in long wavelength infrared (LWIR) and THz spectral ranges for detection of concealed objects. For the purpose of investigations, commercial imagers operating in 6.5-11.7 μm and 250GHz (1.25mm) were used. In the article, we present the measurement setup and the results of measurements in various operating conditions. Theoretical studies of both spectral bands focused on detection of objects with passive imagers are also presented.

  16. Now the Dark Electron Multiplier does Sense Direction of the Daemon Motion

    NASA Astrophysics Data System (ADS)

    Drobyshevski, E. M.; Drobyshevski, M. E.; Pikulin, V. A.

    Detection of the September maximum in the primary near-Earth daemon flux at high (~ 60°) Northern latitudes by our setup with a plane horizontal scintillator is plagued by purely geometric factors; indeed, because of the Earth's rotation axis being tilted, the daemons catching up with the Earth in outer Near-Earth, Almost Circular Heliocentric Orbits (NEACHOs) strike the Earth along close-to-horizontal paths. Nevertheless, application of only two oppositely oriented, specially designed "dark electron multipliers" of the type TEU-167d (only their ø125-mm front disc is coated on the inside by a thick, ~ 0.5 μm Al layer, which permits such multipliers to detect primarily daemons flying inside them from the base to the disc) has made it possible for us to detect in one experiment, at a confidence level of >3σ, a flux of daemons captured from NEACHOs into Geocentric Earth-Surface-Crossing Orbits, as well as to record a decrease in the velocity of these objects from ~ 10 to ~ 7 km/s in a characteristic time of ~ 1 month resulting from their being slowed down in transits through the Earth's body.

  17. Investigation of MMOD Impact on STS-115 Shuttle Payload Bay Door Radiator

    NASA Technical Reports Server (NTRS)

    Hyde, J.; Christiansen, E.; Lear, D.; Kerr, J.; Lyons, F.; Yasensky, J.

    2007-01-01

    The Orbiter radiator system consists of eight individual 4.6 m x 3.2 m panels located with four on each payload bay door. Forward panels #1 and #2 are 2.3 cm thick while the aft panels #3 and #4 have a smaller overall thickness of 1.3 cm. The honeycomb radiator panels consist of 0.028 cm thick Aluminum 2024-T81 facesheets and Al5056-H39 cores. The face-sheets are topped with 0.005 in. (0.127 mm) silver-Teflon tape. The radiators are located on the inside of the shuttle payload bay doors, which are closed during ascent and reentry, limiting damage to the on-orbit portion of the mission. Post-flight inspections at the Kennedy Space Center (KSC) following the STS-115 mission revealed a large micrometeoroid/orbital debris (MMOD) impact near the hinge line on the #4 starboard payload bay door radiator panel. The features of this impact make it the largest ever recorded on an orbiter payload bay door radiator. The general location of the damage site and the adjacent radiator panels can be seen in Figure 2. Initial measurements of the defect indicated that the hole in the facesheet was 0.108 in. (2.74 mm) in diameter. Figure 3 shows an image of the front side damage. Subsequent observations revealed exit damage on the rear facesheet. Impact damage features on the rear facesheet included a 0.03 in. diameter hole (0.76 mm), a approx.0.05 in. tall bulge (approx.1.3 mm), and a larger approx.0.2 in. tall bulge (approx.5.1 mm) that exhibited a crack over 0.27 in. (6.8 mm) long. A large approx.1 in. (25 mm) diameter region of the honeycomb core was also damaged. Refer to Figure 4 for an image of the backside damage to the panel. No damage was found on thermal blankets or payload bay door structure under the radiator panel. Figure 5 shows the front facesheet with the thermal tape removed. Ultrasound examination indicated a maximum facesheet debond extent of approximately 1 in. (25 mm) from the entry hole. X-ray examinations revealed damage to an estimated 31 honeycomb cells with an extent of 0.85 in. x 1.1 in. (21.6 x 27.9 mm). Pieces of the radiator at and surrounding the impact site were recovered during the repair procedures at KSC. They included the thermal tape, front facesheet, honeycomb core, and rear facesheet. These articles were examined at JSC using a scanning electron microscope (SEM) with an energy dispersive x-ray spectrometer (EDS). Figure 6 shows SEM images of the entry hole in the facesheet. The asymmetric height of the lip may be attributed to projectile shape and impact angle. Numerous instances of a glass-fiber organic matrix composite were observed in the facesheet tape sample. The fibers were approximately 10 micrometers in diameter and variable lengths. EDS analysis indicated a composition of Mg, Ca, Al, Si, and O. Figures 7 and 8 present images of the fiber bundles, which were believed to be circuit board material based on similarity in fiber diameter, orientation, consistency, and composition. A test program was initiated in an attempt to simulate the observed damage to the radiator facesheet and honeycomb. Twelve test shots were performed using projectiles cut from a 1.6 mm thick fiberglass circuit board substrate panel. Results from test HITF07017, shown in figures 9 and 10, correlates with the observed impact features reasonably well. The test was performed at 4.14 km/sec with an impact angle of 45 degrees using a cylindrical projectile with a diameter and length of 1.25 mm. The fiberglass circuit board material had a density of 1.65 g/cu cm, giving a projectile mass of 2.53 mg. An analysis was performed using the Bumper code to estimate the probability of impact to the shuttle from a 1.25 mm diameter particle. Table 1 shows a 1.6% chance (impact odds = 1 in 62) of a 1.25 mm or larger MMOD impact on the radiators of the vehicle during a typical ISS mission. There is a 0.4% chance (impact odds = 1 in 260) that a 1.25 mm or larger MMOD particle would impact the RCC wing leading edge and nose cap during a typical miion. Figure 11 illustrates the vulnerable areas of the wing leading edge reinforced carbon-carbon (RCC), an area of the vehicle that is very sensitive to impact damage. The highlighted red, orange, yellow, and light green areas would be expected to experience critical damage if impacted by an OD particle such as the one that hit the RH4 radiator panel on STS-115.

  18. Long-term Results from Cyclocryotherapy Applied to the 3O'clock and 9O'clock Positions in Blind Refractory Glaucoma Patients

    PubMed Central

    Kim, Byoung Seon; Kim, Young Jun; Seo, Seong Wook; Yoo, Ji Myong

    2015-01-01

    Purpose To report the long-term follow-up results after cyclocryotherapy, applied to the 3-o'clock and 9-o'clock positions in blind refractory glaucoma patients. Methods We retrospectively reviewed the charts of 19 blind patients, and a total of 20 eyes with refractory glaucoma who were treated with cyclocryotherapy. Cyclocryotherapy treatments were performed using a retinal cryoprobe. The temperature of each cyclocryotherapy spot was -80℃ and each spot was maintained in place for 60 seconds. Six cyclocryotherapy spots were placed in each quadrant, including the 3-o'clock and 9-o'clock positions. Results The mean baseline pretreatment intraocular pressure (IOP) in all eyes was 50.9 ± 12.5 mmHg, which significantly decreased to a mean IOP at last follow-up of 14.1 ± 7.1 mmHg (p < 0.001). The mean number of antiglaucoma medications that patients were still taking at last follow-up was 0.3 ± 0.6. Devastating post-procedure phthisis occurred in only one eye. Conclusions Cyclocryotherapy, performed at each quadrant and at the 3-o'clock and 9-o'clock position, is an effective way to lower IOP and, thus, is a reasonable treatment option for refractory glaucoma patients who experience with ocular pain and headaches. PMID:25646060

  19. Simplified stereo-optical ultrasound plane calibration

    NASA Astrophysics Data System (ADS)

    Hoßbach, Martin; Noll, Matthias; Wesarg, Stefan

    2013-03-01

    Image guided therapy is a natural concept and commonly used in medicine. In anesthesia, a common task is the injection of an anesthetic close to a nerve under freehand ultrasound guidance. Several guidance systems exist using electromagnetic tracking of the ultrasound probe as well as the needle, providing the physician with a precise projection of the needle into the ultrasound image. This, however, requires additional expensive devices. We suggest using optical tracking with miniature cameras attached to a 2D ultrasound probe to achieve a higher acceptance among physicians. The purpose of this paper is to present an intuitive method to calibrate freehand ultrasound needle guidance systems employing a rigid stereo camera system. State of the art methods are based on a complex series of error prone coordinate system transformations which makes them susceptible to error accumulation. By reducing the amount of calibration steps to a single calibration procedure we provide a calibration method that is equivalent, yet not prone to error accumulation. It requires a linear calibration object and is validated on three datasets utilizing di erent calibration objects: a 6mm metal bar and a 1:25mm biopsy needle were used for experiments. Compared to existing calibration methods for freehand ultrasound needle guidance systems, we are able to achieve higher accuracy results while additionally reducing the overall calibration complexity. Ke

  20. A Mathematical Model of Oxygen Transport in Skeletal Muscle During Hindlimb Unloading

    NASA Technical Reports Server (NTRS)

    Causey, Laura; Lewandowski, Beth E.; Weinbaum, Sheldon

    2014-01-01

    During hindlimb unloading (HU) dramatic fluid shifts occur within minutes of the suspension, leading to a less precise matching of blood flow to O2 demands of skeletal muscle. Vascular resistance directs blood away from certain muscles, such as the soleus (SOL). The muscle volume gradually reduces in these muscles so that eventually the relative blood flow returns to normal. It is generally believed that muscle volume change is not due to O2 depletion, but a consequence of disuse. However, the volume of the unloaded rat muscle declines over the course of weeks, whereas the redistribution of blood flow occurs immediately. Using a Krogh Cylinder Model, the distribution of O2 was predicted in two skeletal muscles: SOL and gastrocnemius (GAS). Effects of the muscle blood flow, volume, capillary density, and O2 uptake, are included to calculate the pO2 at rest and after 10 min and 15 days of unloading. The model predicts that 32 percent of the SOL muscle tissue has a pO2 1.25 mm Hg within 10 min, whereas the GAS maintains normal O2 levels, and that equilibrium is reached only as the SOL muscle cells degenerate. The results provide evidence that there is an inadequate O2 supply to the mitochondria in the SOL muscle after 10 min HU.

  1. Negative Pressure Wound Therapy With Instillation and Dwell Time Used to Treat Infected Orthopedic Implants: A 4-patient Case Series.

    PubMed

    Dettmers, Robert; Brekelmans, Wouter; Leijnen, Michiel; van der Burg, Boudewijn; Ritchie, Ewan

    2016-09-01

    Infection following orthopedic implants for bone fixation or joint replacement is always serious and may require removal of the osteosynthetic material. Negative pressure wound therapy with instillation and dwell time (NPWTi-d) is an emerging therapy for the treatment of complex wounds, including infected wounds with osteosynthetic material. The purpose of this case study was to evaluate the outcomes of 4 patients (1 man, 3 women; age range 49 to 71 years) with a postoperative wound infection (POWI) following fracture repair and internal fixation. All patients were at high risk for surgical complications, including infections. Standard infection treatments (antibiotics) had been unsuccessful. Based on the available literature, a NPWTi-d protocol was developed. Following surgical debridement, wounds were instilled with polyhexanide biguanide with a set dwell time of 15 minutes, followed by continuous NPWTi-d of -125 mm Hg for 4 hours. The system was changed every 3 to 4 days until sufficient granulation tissue was evident and negative pressure without instillation could be used. Systemic antibiotics were continued in all patients. Granulation tissue was found to be sufficient in 12 to 35 days in the 4 cases, no recurrence of infection was noted, and the osteosynthesis material remained in place. No adverse events were observed. Research is needed to compare the safety and effectiveness of this adjunct treatment in the management of challenging wounds to other patient and wound management approaches.

  2. Cryogenic magnetic bearing scanning mechanism design for the SPICA/SAFARI Fourier transform spectrometer

    NASA Astrophysics Data System (ADS)

    van den Dool, Teun C.; Hamelinck, Roger F. M. M.; Kruizinga, Bob; Gielesen, Wim L. M.; Braam, Ben C.; Nijenhuis, Jan R.; Loix, Nicolas; Luyckx, Stanislas; van Loon, Dennis; Kooijman, Peter Paul; Swinyard, Bruce M.

    2010-07-01

    TNO, together with its partners Micromega and SRON, have designed a cryogenic scanning mechanism for use in the SAFARI Fourier Transform Spectrometer (FTS) on board of the SPICA mission. The optics of the FTS scanning mechanism (FTSM) consists of two back-to-back cat's-eyes. The optics are mounted on a central "back-bone" tube which houses all the important mechatronic parts: the magnetic bearing linear guiding system, a magnetic linear motor serving as the OPD actuator, internal metrology with nanometer resolution, and a launch lock. A magnetic bearing is employed to enable a large scanning stroke in a small volume. It supports the optics in a free-floating way with no friction, or other non-linearities, enabling sub-nanometer accuracy within a single stage with a stroke of -4 mm to +31.5 mm. Because the FTSM will be used at cryogenic temperatures of 4 Kelvin, the main structure and optics are all constructed from 6061 Aluminum. The overall outside dimensions of the FTSM are: 393 x 130 x 125 mm, and the mass is 2.2 kg.

  3. Aerogel-Based Insulation for High-Temperature Industrial Processes

    SciTech Connect

    Dr. Owen Evans

    2011-10-13

    Under this program, Aspen Aerogels has developed an industrial insulation called Pyrogel HT, which is 4-5 times more thermally efficient than current non-aerogel technology. Derived from nanoporous silica aerogels, Pyrogel HT was specifically developed to address a high temperature capability gap not currently met with Aspen Aerogels{trademark} flagship product, Pyrogel XT. Pyrogel XT, which was originally developed on a separate DOE contract (DE-FG36-06GO16056), was primarily optimized for use in industrial steam processing systems, where application temperatures typically do not exceed 400 C. At the time, further improvements in thermal performance above 400 C could not be reasonably achieved for Pyrogel XT without significantly affecting other key material properties using the current technology. Cumulative sales of Pyrogel HT into domestic power plants should reach $125MM through 2030, eventually reaching about 10% of the total insulation market share in that space. Global energy savings would be expected to scale similarly. Over the same period, these sales would reduce domestic energy consumption by more than 65 TBtu. Upon branching out into all industrial processes in the 400 C-650 C regime, Pyrogel HT would reach annual sales levels of $150MM, with two-thirds of that being exported.

  4. Effects of maximum aggregate size on UPV of brick aggregate concrete.

    PubMed

    Mohammed, Tarek Uddin; Mahmood, Aziz Hasan

    2016-07-01

    Investigation was carried out to study the effects of maximum aggregate size (MAS) (12.5mm, 19.0mm, 25.0mm, 37.5mm, and 50.0mm) on ultrasonic pulse velocity (UPV) of concrete. For investigation, first class bricks were collected and broken to make coarse aggregate. The aggregates were tested for specific gravity, absorption capacity, unit weight, and abrasion resistance. Cylindrical concrete specimens were made with different sand to aggregate volume ratio (s/a) (0.40 and 0.45), W/C ratio (0.45, 0.50, and 0.55), and cement content (375kg/m(3) and 400kg/m(3)). The specimens were tested for compressive strength and Young's modulus. UPV through wet specimen was measured using Portable Ultrasonic Non-destructive Digital Indicating Tester (PUNDIT). Results indicate that the pulse velocity through concrete increases with an increase in MAS. Relationships between UPV and compressive strength; and UPV and Young's modulus of concrete are proposed for different maximum sizes of brick aggregate.

  5. Measurement of tear production using phenol red thread and standardized endodontic absorbent paper points in European pond turtles (Emys orbicularis).

    PubMed

    Rajaei, Seyed Mehdi; Mood, Maneli Ansari; Ghaffari, Masoud Selk; Williams, David L

    2014-12-01

    The objective of this study was to determine the aqueous fraction of the tear film using the phenol red thread test (PRTT) and paper point tear test (PPTT) in healthy adult European pond turtles (Emys orbicularis). Twenty-four healthy adult European pond turtles were studied. Measurement of tear secretion was performed using the PRTT and standardized endodontic absorbent PPTT. Horizontal palpebral fissure length (HPFL) was measured using digital calipers and was correlated with the weight of the animal. The mean ± SD PRTT, PPTT, and HPFL values for the left and right eyes were 5.12 ± 1.54 mm/15 sec and 4.62 ± 1.76 mm/15 sec; 4.50 ± 1.25 mm/1 min and 4.20 ± 1.53 mm/1 min; and 8.4 ± 0.6 mm and 8.3 ± 0.6 mm, respectively. No significant differences were detected between right and left eyes of individual turtles or between males and females in all tests. This study represents reference values of tear production in European pond turtles obtained from PRTT and PPTT methods and forms an important baseline study in defining the healthy chelonian ocular surface.

  6. The use of negative pressure in critical necrotizing fasciitis treatment: a case presentation.

    PubMed

    Ge, Kui; Xu, Bing; Wu, Jia-Jun; Wu, Minjie; Lu, Shuliang; Xie, Ting

    2014-09-01

    Surgery complemented by antibiotics forms the backbone of the successful management of necrotizing fasciitis. But it will be very difficult to clear away extensive necrotizing tissue thoroughly in critically ill patients when their vital signs are unstable. The authors report the case of a 33-year-old woman who had extensive necrotizing fasciitis of the right lower limb with septic shock. The patient was severely anemic and malnutrition and had been given conservative debridement at bedside, that is, only detached necrotizing tissues was taken away while some other necrotizing tissue still remained, so that the skin tissue within the same area could be saved as much as possible. After debridement, negative pressure was applied at 125 mm Hg. Broad-spectrum antibiotics and effective supplementation were also complemented, thus controlling the septic shock. All necrotizing tissues were detached, and the sparing vital skin on necrotizing fascia was preserved successfully after negative pressure treatment. The patient was finally saved. In conclusion, negative pressure treatment may help diminish toxin absorbance, detach gangrene tissue, and preserve sparing vital tissue. This case suggests the value of combined use of negative pressure therapy and conservative debridement in critically ill patients with extensive necrotizing fasciitis.

  7. Deep Orbital Dermoid Cyst Bulging into the Superior Orbital Fissure: Clinical Presentation and Management.

    PubMed

    Kumar, Ravinder; Vyas, Kapil; Jaiswal, Gagan; Bhargava, Abhishek; Kundu, Jyoti

    2017-01-01

    To present a case of deep orbital dermoid cyst with emphasis on clinical presentation, imaging spectrum, differential diagnosis and management. A 28-year-old female was referred to our hospital with chief complaint of drooping of right eyelid and progressive headache. Ocular motility, visual acuity and fundus examination were normal. computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well-defined, intraosseous deep orbital dermoid cyst (5.9 mm × 12.5 mm) located near the apex of right orbit, extending from greater wing of sphenoid into the superior orbital fissure. Due to occulomotor nerve (superior and inferior divisions) compression which passes through the superior orbital fissure, ipsilateral headache and ptosis occurred. Complete surgical excision of cyst was performed using noninvasive extracranial lateral orbitotomy approach. After removal of the cyst, curette and cutting drill were used to thoroughly remove any residual cystic content. Histopathological analysis confirmed the diagnosis. The healing was uneventful postoperatively. CT and MRI are easy, reliable, safe and effective imaging methods for establishing the diagnosis of orbital dermoid cyst. Size, location and manifestations are the most important determinants of the disease management. Complete surgical excision without rupture of the cyst is the treatment of choice.

  8. The effect of CT scanner parameters and 3D volume rendering techniques on the accuracy of linear, angular, and volumetric measurements of the mandible

    PubMed Central

    Whyms, B.J.; Vorperian, H.K.; Gentry, L.R.; Schimek, E.M.; Bersu, E.T.; Chung, M.K.

    2013-01-01

    Objectives This study investigates the effect of scanning parameters on the accuracy of measurements from three-dimensional multi-detector computed tomography (3D-CT) mandible renderings. A broader range of acceptable parameters can increase the availability of CT studies for retrospective analysis. Study Design Three human mandibles and a phantom object were scanned using 18 combinations of slice thickness, field of view, and reconstruction algorithm and three different threshold-based segmentations. Measurements of 3D-CT models and specimens were compared. Results Linear and angular measurements were accurate, irrespective of scanner parameters or rendering technique. Volume measurements were accurate with a slice thickness of 1.25 mm, but not 2.5 mm. Surface area measurements were consistently inflated. Conclusions Linear, angular and volumetric measurements of mandible 3D-CT models can be confidently obtained from a range of parameters and rendering techniques. Slice thickness is the primary factor affecting volume measurements. These findings should also apply to 3D rendering using cone-beam-CT. PMID:23601224

  9. On the penetration depth of reactive oxygen and nitrogen species generated by a plasma jet through real biological tissue

    NASA Astrophysics Data System (ADS)

    Duan, J.; Lu, X.; He, G.

    2017-07-01

    In this work, an actual biological tissue is used to investigate how thick the reactive oxygen and nitrogen species (RONS) produced by a plasma jet can penetrate through the tissue. This is one of the most critical questions in plasma medicine. The concentration of RONS (O3, H2O2, OH, NO2-, NO2- + NO3-) produced by the plasma jet penetrating through different thickness of the tissue is measured. It is found that the reactive oxygen species (ROS) produced by the plasma are significantly consumed by the tissue. For the tissue thickness of 500 μm, there is only about five percent or even less of the ROS (O3, H2O2, and OH) penetrating through the tissue. On the other hand, more than 80% of the reactive nitrogen species (NO2- + NO3-) are able to penetrate through the 500 μm biological tissue. Furthermore, under certain experimental conditions, some of the RONS can penetrate through 1.25 mm of the biological tissue. Finally, besides H2O2, NO2-, and NO3-, there is some other unknown RONS that penetrate through the biological tissue.

  10. Mechanical isolation of the inner cell mass is effective in derivation of new human embryonic stem cell lines.

    PubMed

    Ström, Susanne; Inzunza, José; Grinnemo, Karl-Henrik; Holmberg, Kerstin; Matilainen, Eija; Strömberg, Anne-Marie; Blennow, Elisabeth; Hovatta, Outi

    2007-12-01

    For clinical grade human embryonic stem cell (hESC) lines, a robust derivation system without any substances having animal origin would be required. We have gradually improved our hESC derivations. Human skin fibroblasts were used as feeder cells in derivation of all our 25 permanent fully characterized hESC lines. In the first four derivations, fetal calf serum was used as a supplement in the medium, thereafter, serum replacement medium was used. Immunosurgery generally used for isolation of the inner cell mass (ICM) still involves animal serum and complement. We developed a practical mechanical isolation method for the ICM. Two flexible metal needles with sharpened tips, 0.125 mm in diameter, were used to open the zona pellucida and extract the ICM under a stereomicroscope. Immunohistochemical and karyotype characterization of the new hESC lines was carried out, and pluripotency was tested in vitro (immunocytochemistry and RT-PCR) and in vivo (teratoma growth). Five hESC lines were obtained from 19 supernumerary blastocysts collected in 2005-2006 (26%), whereas in similar conditions, we obtained 16 lines from 100 blastocysts (16%) using immunosurgery in 2003-2005. The new lines had a normal karyotype and tissues originating from the three embryonic germ cell layers were present. Mechanical isolation of the ICM proved to be an effective way to derive new hESC lines. The technique is fast, does not require any extra investment and the xeno-components of immunosurgery could be avoided.

  11. [Arterial vascularization of the triceps sural muscle].

    PubMed

    Mairesse, J L; Mestdagh, H; Procyk, S; Depreux, R

    1984-01-01

    The triceps surae muscle, the dorsal and medial leg skin constitute a very important reserve of muscular and myocutaneous flaps. The material on which the study was carried out consisted of 20 legs from standard cadavers. The superficialis femoral artery was injected with terebenthene and minimum mixture. The medial head of gastrocnemius is 23.3 em long, 6.9 cm wide, 1.25 mm thick at distal third. Its dominant blood supply is carried by the medialis gastrocnemius artery. It rises from popliteal artery 1.2 cm above the femoral tibial articulation with 1.9 mm diameter. It runs 3 cm down before entering muscle where it provides 2 or 3 mean branches. These branches give musculocutaneous arteries to the skin of the dorsal leg. The same study was performed for the lateral head of gastrocnemius and soleus. We studied also arteries of dorsomedial leg skin. The characteristics of long saphenous and short saphenous arteries were described. These muscles and dorsomedial leg skin can be used as muscular or myocutaneous flap for covering defects between the lower leg and the lower thigh.

  12. The Solanum lycopersicum Zinc Finger2 Cysteine-2/Histidine-2 Repressor-Like Transcription Factor Regulates Development and Tolerance to Salinity in Tomato and Arabidopsis1[W

    PubMed Central

    Hichri, Imène; Muhovski, Yordan; Žižková, Eva; Dobrev, Petre I.; Franco-Zorrilla, Jose Manuel; Solano, Roberto; Lopez-Vidriero, Irene; Motyka, Vaclav; Lutts, Stanley

    2014-01-01

    The zinc finger superfamily includes transcription factors that regulate multiple aspects of plant development and were recently shown to regulate abiotic stress tolerance. Cultivated tomato (Solanum lycopersicum Zinc Finger2 [SIZF2]) is a cysteine-2/histidine-2-type zinc finger transcription factor bearing an ERF-associated amphiphilic repression domain and binding to the ACGTCAGTG sequence containing two AGT core motifs. SlZF2 is ubiquitously expressed during plant development, and is rapidly induced by sodium chloride, drought, and potassium chloride treatments. Its ectopic expression in Arabidopsis (Arabidopsis thaliana) and tomato impaired development and influenced leaf and flower shape, while causing a general stress visible by anthocyanin and malonyldialdehyde accumulation. SlZF2 enhanced salt sensitivity in Arabidopsis, whereas SlZF2 delayed senescence and improved tomato salt tolerance, particularly by maintaining photosynthesis and increasing polyamine biosynthesis, in salt-treated hydroponic cultures (125 mm sodium chloride, 20 d). SlZF2 may be involved in abscisic acid (ABA) biosynthesis/signaling, because SlZF2 is rapidly induced by ABA treatment and 35S::SlZF2 tomatoes accumulate more ABA than wild-type plants. Transcriptome analysis of 35S::SlZF2 revealed that SlZF2 both increased and reduced expression of a comparable number of genes involved in various physiological processes such as photosynthesis, polyamine biosynthesis, and hormone (notably ABA) biosynthesis/signaling. Involvement of these different metabolic pathways in salt stress tolerance is discussed. PMID:24567191

  13. A sub-10 nA DC-balanced adaptive stimulator IC with multi-modal sensor for compact electro-acupuncture stimulation.

    PubMed

    Song, Kiseok; Lee, Hyungwoo; Hong, Sunjoo; Cho, Hyunwoo; Ha, Unsoo; Yoo, Hoi-Jun

    2012-12-01

    A compact electro-acupuncture (EA) system is proposed for a multi-modal feedback EA treatment. It is composed of a needle, a compact EA patch, and an interconnecting conductive thread. The 3 cm diameter compact EA patch is implemented with an adaptive stimulator IC and a small coin battery on the planar-fashionable circuit board (P-FCB) technology. The adaptive stimulator IC can form a closed current loop for even a single needle, and measure the electromyography (EMG) and the skin temperature to analyze the stimulation status as well as supply programmable stimulation current (40 μA-1 mA) with 5 different modes. The large time constant (LTC) sample and hold (S/H) current matching technique achieves the high-precision charge balancing ( <;10 nA) for the patient's safety. The measured data can be wirelessly transmitted to the external EA analyzer through the body channel communication (BCC) transceiver for the low power consumption. The external EA analyzer can show the patient's status, such as the muscle fatigue and the change of the skin temperature. Based on these analyses, the practitioner can adaptively change the stimulation parameters for the optimal treatment value. A 12.5 mm(2) 0.13 μm RF CMOS stimulator chip consumes 6.8 mW at 1.2 V supporting 32 different current levels. The proposed compact EA system is fully implemented and tested on the human body.

  14. Ion projection lithography: November 2000 status and sub-70-nm prospects

    NASA Astrophysics Data System (ADS)

    Kaesmaier, Rainer; Wolter, Andreas; Loeschner, Hans; Schunck, Stefan

    2000-10-01

    Among all next generation lithography (NGL) options Ion Projection Lithography (IPL) offers the smallest (particle) wavelength of 5x10- 5nm (l00keV Helium ions). Thus, 4x reduction ion-optics has diffraction limits <3nm even when using a numerical aperture as low as NAequals10-5. As part of the European MEDEA IPL project headed by Infineon Technologies wide field ion-optics have been designed by IMS- Vienna with predicted resolution of 50nm within a 12.5mm exposure field. The ion-optics part of the PDT tool (PDT-IOS) has been realized and assembled. In parallel to the PDT-IOS effort, at Leica Jena a test bench for a vertical vacuum 300mm-wafer stage has been realized. Operation of magnetic bearing supported stage movement has already been demonstrated. As ASML vacuum compatible optical wafer alignment system, with 3nm(3(sigma) ) precision demonstrated in air, has been integrated to this wafer test bench system recently. Parallel to the IPL tool development, Infineon Technologies Mask House and the Institute for Microelectronics Stuttgart are intensively working on the development of IPL stencil masks with success in producing 150mm and 200mm stencil masks as reported elsewhere. This paper is focused on information about the status of the PDT-IOS tool.

  15. Lightweight photovoltaic module development for unmanned aerial vehicles

    SciTech Connect

    Nowlan, M.J.; Maglitta, J.C.; Lamp, T.R.

    1998-07-01

    Lightweight photovoltaic modules are being developed for powering high altitude unmanned aerial vehicles (UAVs). Terrestrial crystalline silicon solar cell and module technologies are being applied to minimize module cost, with modifications to improve module specific power (W/kg) and power density (W/m{sup 2}). New module processes are being developed for assembling standard thickness (320 mm) and thin (125 mm) solar cells, thin (50 to 100 mm) encapsulant films, and thin (25 mm) cover films. In comparison, typical terrestrial modules use 300 to 400 mm thick solar cells, 460 mm thick encapsulants, and 3.2 mm thick glass covers. The use of thin, lightweight materials allows the fabrication of modules with specific powers ranging from 120 to 200 W/kg, depending on cell thickness and efficiency, compared to 15 W/kg or less for conventional terrestrial modules. High efficiency designs based on ultra-thin (5 mm) GaAs cells have also been developed, with the potential for achieving substantially higher specific powers. Initial design, development, and module assembly work is completed. Prototype modules were fabricated in sizes up to 45 cm x 99 cm. Module materials and processes are being evaluated through accelerated environmental testing, including thermal cycling, humidity-freeze cycling, mechanical cycling, and exposure to UV and visible light.

  16. Four dimensional deformable image registration using trajectory modeling

    PubMed Central

    Castillo, Edward; Castillo, Richard; Martinez, Josue; Shenoy, Maithili; Guerrero, Thomas

    2013-01-01

    A four-dimensional deformable image registration (4D DIR) algorithm, referred to as 4D local trajectory modeling (4DLTM), is presented and applied to thoracic 4D computed tomography (4DCT) image sets. The theoretical framework on which this algorithm is built exploits the incremental continuity present in 4DCT component images to calculate a dense set of parameterized voxel trajectories through space as functions of time. The spatial accuracy of the 4DLTM algorithm is compared with an alternative registration approach in which component phase to phase (CPP) DIR is utilized to determine the full displacement between maximum inhale and exhale images. A publically available DIR reference database (http://www.dir-lab.com) is utilized for the spatial accuracy assessment. The database consists of ten 4DCT image sets and corresponding manually identified landmark points between the maximum phases. A subset of points are propagated through the expiratory 4DCT component images. Cubic polynomials were found to provide sufficient flexibility and spatial accuracy for describing the point trajectories through the expiratory phases. The resulting average spatial error between the maximum phases was 1.25 mm for the 4DLTM and 1.44 mm for the CPP. The 4DLTM method captures the long-range motion between 4DCT extremes with high spatial accuracy. PMID:20009196

  17. A quantitative cell modeling and wound-healing analysis based on the Electric Cell-substrate Impedance Sensing (ECIS) method.

    PubMed

    Yang, Jen Ming; Chen, Szi-Wen; Yang, Jhe-Hao; Hsu, Chih-Chin; Wang, Jong-Shyan

    2016-02-01

    In this paper, a quantitative modeling and wound-healing analysis of fibroblast and human keratinocyte cells is presented. Our study was conducted using a continuous cellular impedance monitoring technique, dubbed Electric Cell-substrate Impedance Sensing (ECIS). In fact, we have constructed a mathematical model for quantitatively analyzing the cultured cell growth using the time series data directly derived by ECIS in a previous work. In this study, the applicability of our model into the keratinocyte cell growth modeling analysis was assessed first. In addition, an electrical "wound-healing" assay was used as a means to evaluate the healing process of keratinocyte cells at a variety of pressures. Two innovative and new-defined indicators, dubbed cell power and cell electroactivity, respectively, were developed for quantitatively characterizing the biophysical behavior of cells. We then employed the wavelet transform method to perform a multi-scale analysis so the cell power and cell electroactivity across multiple observational time scales may be captured. Numerical results indicated that our model can well fit the data measured from the keratinocyte cell culture for cell growth modeling analysis. Also, the results produced by our quantitative analysis showed that the wound healing process was the fastest at the negative pressure of 125mmHg, which consistently agreed with the qualitative analysis results reported in previous works. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Pushing spatial and temporal resolution for functional and diffusion MRI in the Human Connectome Project

    PubMed Central

    Uğurbil, Kamil; Xu, Junqian; Auerbach, Edward J.; Moeller, Steen; Vu, An; Duarte-Carvajalino, Julio M.; Lenglet, Christophe; Wu, Xiaoping; Schmitter, Sebastian; Van de Moortele, Pierre Francois; Strupp, John; Sapiro, Guillermo; De Martino, Federico; Wang, Dingxin; Harel, Noam; Garwood, Michael; Chen, Liyong; Feinberg, David A.; Smith, Stephen M.; Miller, Karla L.; Sotiropoulos, Stamatios N; Jbabdi, Saad; Andersson, Jesper L; Behrens, Timothy EJ; Glasser, Matthew F.; Van Essen, David; Yacoub, Essa

    2013-01-01

    The human connectome project (HCP) relies primarily on three complementary magnetic resonance (MR) methods. These are: 1) resting state functional MR imaging (rfMRI) which uses correlations in the temporal fluctuations in an fMRI time series to deduce ‘functional connectivity’; 2) diffusion imaging (dMRI), which provides the input for tractography algorithms used for the reconstruction of the complex axonal fiber architecture; and 3) task based fMRI (tfMRI), which is employed to identify functional parcellation in the human brain in order to assist analyses of data obtained with the first two methods. We describe technical improvements and optimization of these methods as well as instrumental choices that impact speed of acquisition of fMRI and dMRI images at 3 Tesla, leading to whole brain coverage with 2 mm isotropic resolution in 0.7 second for fMRI, and 1.25 mm isotropic resolution dMRI data for tractography analysis with three-fold reduction in total data acquisition time. Ongoing technical developments and optimization for acquisition of similar data at 7 Tesla magnetic field are also presented, targeting higher resolution, specificity of functional imaging signals, mitigation of the inhomogeneous radio frequency (RF) fields and power deposition. Results demonstrate that overall, these approaches represent a significant advance in MR imaging of the human brain to investigate brain function and structure. PMID:23702417

  19. Muscular hydrostat mechanism for lip protrusion in speech

    NASA Astrophysics Data System (ADS)

    Murano, Emi Z.; Stone, Maureen; Honda, Kiyoshi

    2005-09-01

    The lip is an organ consisting mostly of muscle similar to the tongue. While the tongue is known as a muscular hydrostat, it is unclear whether the lip is also. In this paper the muscular hydrostat issue was explored from the anatomical and functional point of view using high-resolution static MRI (hr-MRI 0.125 mm/pixel) and tagged-cineMRI (t-MRI). A 3-D reconstruction of the lips and its muscles was obtained from hr-MRI during sustained vowels /i/ and /u/. The muscular geometry of the orbicularis oris, mentalis, and depressor labii inferior muscles were superimposed onto the principal strains that depicts compression and expansion of the internal tissue obtained from t-MRI. It is shown that (1) orbicularis oris muscle shape can predict both the borderline of glabrous and hairy skin and the manner in which the lips are protruded; (2) the lips volume is almost identical for both speech tasks; and (3) direction and intensity of compression of orbicularis oris and mentalis muscle bundles imply the role of these muscles in the protrusion appearance. These results indicate that the muscular architecture and volume preserving characteristics of the lips are consistent with a muscular hydrostat. [This work was supported by NIH (USA) and NiCT (Japan).

  20. Experimental investigation of the dynamic elastic modulus and vibration damping in molybdenum and alumina-coated Ti-25Al-10Nb-3V-1Mo aluminides cycled at elevated temperatures

    SciTech Connect

    Wolfenden, A.; Cantu, M.W.; Vaidya, R.U.

    1996-04-01

    Titanium aluminides such as Ti-25Al-10Nb-3V-1Mo have became the focus of high temperature materials research due to their ability to maintain their strength up to 1,000{degree}C. However, at temperatures in excess of 650{degree}C, Ti-25Al-10Nb-3V-1Mo undergoes severe oxidation which, in turn, can degrade its mechanical properties. To address this problem, plasma sprayed coatings were applied to the substrate to provide protection in the high temperature environment. In this study, 0.1-0.125 mm thick alumina and molybdenum coatings were plasma sprayed onto a Ti-25Al-10Nb-3V-1Mo substrate. Changes in dynamic elastic modulus and vibration damping due to thermal cycling at elevated temperatures were measured. The modulus and damping were measured using the piezoelectric ultrasonic composite oscillator technique (PUCOT). The behavior of the Al{sub 2}O{sub 3} and Mo coated specimens was compared to that of the uncoated samples. Thermal cycling of the coated samples at 600{degree}C led to an increase in the modulus and decrease in the damping. Most of the changes in properties occurred after the first thermal cycle. Thermal cycling of the samples at 750{degree}C and 850{degree}C led to complete failure of the coatings. A specimen with a 1.0 mm alumina coating exhibited cracks even when cycled at 600{degree}C. 7 refs., 12 figs., 3 tabs.

  1. A 4-channel 3 Tesla phased array receive coil for awake rhesus monkey fMRI and diffusion MRI experiments.

    PubMed

    Khachaturian, Mark Haig

    2010-01-01

    Awake monkey fMRI and diffusion MRI combined with conventional neuroscience techniques has the potential to study the structural and functional neural network. The majority of monkey fMRI and diffusion MRI experiments are performed with single coils which suffer from severe EPI distortions which limit resolution. By constructing phased array coils for monkey MRI studies, gains in SNR and anatomical accuracy (i.e., reduction of EPI distortions) can be achieved using parallel imaging. The major challenges associated with constructing phased array coils for monkeys are the variation in head size and space constraints. Here, we apply phased array technology to a 4-channel phased array coil capable of improving the resolution and image quality of full brain awake monkey fMRI and diffusion MRI experiments. The phased array coil is that can adapt to different rhesus monkey head sizes (ages 4-8) and fits in the limited space provided by monkey stereotactic equipment and provides SNR gains in primary visual cortex and anatomical accuracy in conjunction with parallel imaging and improves resolution in fMRI experiments by a factor of 2 (1.25 mm to 1.0 mm isotropic) and diffusion MRI experiments by a factor of 4 (1.5 mm to 0.9 mm isotropic).

  2. The induction of dentin bridge-like structures by constructs of subcultured dental pulp-derived cells and porous HA/TCP in porcine teeth.

    PubMed

    Ando, Yusuke; Honda, Masaki J; Ohshima, Hayato; Tonomura, Akiko; Ohara, Takayuki; Itaya, Toshimitsu; Kagami, Hideaki; Ueda, Minoru

    2009-02-01

    The purpose of this study was to investigate dentin-bridge formation in teeth following the transplantation of dental pulp-derived cells seeded on hydroxyapatite/tricalcium phosphate (HA/TCP) scaffolds. The dental pulp tissues were removed from the extracted first molar teeth of miniature pigs and single cell populations were subcultured. Second-passage cells that had alkaline phosphatase activity were combined with scaffolds. Cell-scaffold constructs were placed in contact with the exposed pulp tissue. The dimensions of the exposed pulp site were approximately 1-2.5 mm in diameter and 2-3 mm in depth from the tooth surface. After placing the constructs, the tooth was restored with composite resin. Six weeks after transplantation, hard tissue formation was observed on the pulp tissue in histology. Dentinal tubule-like structures were observed in most of the hard tissue generated, and columnar cells, which showed positive immunoreactions with dentin sialoprotein (DSP) and heat shock protein (HSP)-25, were aligned beneath the hard tissues. When only scaffolds were placed on the pulp tissues, particles of hard tissue were formed, however dentinal tubule-like structures and odontoblasts were not observed despite the formation of hard tissue. In conclusion, the implantation of dental pulp constructs into pulp exposed stimulates the formation of calcified dentin-like structures.

  3. Stabilization of Coronary Stents Using the Floating-Wire Technique.

    PubMed

    Li, Yue; Xue, Jingyi; Li, Shuang; Sheng, Li; Sun, Danghui; Li, Weimin; Gong, Yongtai

    2015-11-01

    Excessive movement of coronary stents within the artery can make accurate stent placement difficult. This study assessed the use of the floating-wire technique to reduce stent motion to improve placement accuracy. During percutaneous coronary intervention, if excessive stent movement prevented accurate stent placement, the floating-wire technique was performed to reduce stent motion within the coronary artery during both stent positioning and deployment. Postprocedural angiograms were analyzed by two independent operators to measure the motion length of the stent delivery system relative to the coronary artery before and after using the floating-wire technique. The floating-wire technique was considered necessary in 19 patients. No procedural complications occurred. The extent of motion was markedly reduced by using the floating-wire technique (4.04 ± 1.25 mm to 1.11 ± 0.81 mm; P<.001). The floating-wire technique is an effective and safe method to reduce stent movement and facilitate accurate stent deployment. This simple technique can be easily applied in any interventional cardiac catheterization laboratory without the need for additional training or equipment.

  4. Liberation characteristic and physical separation of printed circuit board (PCB).

    PubMed

    Guo, Chao; Wang, Hui; Liang, Wei; Fu, Jiangang; Yi, Xin

    2011-01-01

    Recycling of printed circuit board (PCB) is an important subject and to which increasing attention is paid, both in treatment of waste as well as recovery of valuable material terms. Precede physical and mechanical method, a good liberation is the premise to further separation. In this study, two-step crushing process is employed, and standard sieve is applied to screen crushed material to different size fractions, moreover, the liberation situation and particles shape in different size are observed. Then metal of the PCB is separated by physical methods, including pneumatic separation, electrostatic separation and magnetic separation, and major metal contents are characterized by inductively coupled plasma emission spectrometry (ICP-AES). Results show that the metal and nonmetal particles of PCB are dissociated completely under the crush size 0.6mm; metal is mainly enriched in the four size fractions between 0.15 and 1.25 mm; relatively, pneumatic separation is suitable for 0.6-0.9 mm size fraction, while the electrostatic separation is suitable for three size fractions that are 0.15-0.3mm, 0.3-0.6mm and 0.9-1.25 mm. The whole process that involves crushing, electrostatic and magnetic separation has formed a closed cycle that can return material and provide salable product.

  5. Large filters for wide-field survey telescope LSST

    NASA Astrophysics Data System (ADS)

    Morgado, Nazario; Pinard, Laurent; Sassolas, Benoit; Flaminio, Raffaele; Forest, Daniéle; Lagrange, Bernard; Michel, Christophe; Antilogus, Pierre

    2012-09-01

    The LSST design foresees the use of six wide-band large optical filters that can alternatively be moved in front of the CCD camera. Each of the six filters has a different band-pass covering all the wavelengths from 300 nm to 1200 nm. The way to achieve this is to coat an optimized optical thin films stack on a filter substrate. Each filter requires a specific design using specific appropriate materials. The main characteristics of these filters, that constitute a real technological challenge, are: their relatively large size - their radii of curvature (about 5.6 m) that represent a sagitta of 12,5 mm that increases the uniformity complexity, the large rejection band requirements with transmission lower than 0.01 % out of the band and a transmission of 95 % over the band-pass. This paper proposes to show the problematic and the results obtained at LMA (Laboratoire des Matériaux Avancés-FRANCE) to the purpose of realizing these filters using the IBS (Ion Beam Sputtering) deposition technique. The results obtained with High-Pass/Low-Pass structures will be presented. Experimental results will be shown concerning the R-band filter (552-691 nm). An overview of the work to be done to realize transmittance map over large filters will be given.

  6. Reproducibility of radiomics for deciphering tumor phenotype with imaging.

    PubMed

    Zhao, Binsheng; Tan, Yongqiang; Tsai, Wei-Yann; Qi, Jing; Xie, Chuanmiao; Lu, Lin; Schwartz, Lawrence H

    2016-03-24

    Radiomics (radiogenomics) characterizes tumor phenotypes based on quantitative image features derived from routine radiologic imaging to improve cancer diagnosis, prognosis, prediction and response to therapy. Although radiomic features must be reproducible to qualify as biomarkers for clinical care, little is known about how routine imaging acquisition techniques/parameters affect reproducibility. To begin to fill this knowledge gap, we assessed the reproducibility of a comprehensive, commonly-used set of radiomic features using a unique, same-day repeat computed tomography data set from lung cancer patients. Each scan was reconstructed at 6 imaging settings, varying slice thicknesses (1.25 mm, 2.5 mm and 5 mm) and reconstruction algorithms (sharp, smooth). Reproducibility was assessed using the repeat scans reconstructed at identical imaging setting (6 settings in total). In separate analyses, we explored differences in radiomic features due to different imaging parameters by assessing the agreement of these radiomic features extracted from the repeat scans reconstructed at the same slice thickness but different algorithms (3 settings in total). Our data suggest that radiomic features are reproducible over a wide range of imaging settings. However, smooth and sharp reconstruction algorithms should not be used interchangeably. These findings will raise awareness of the importance of properly setting imaging acquisition parameters in radiomics/radiogenomics research.

  7. Bending and metallurgical properties of rotary endodontic instruments. IV. Gates Glidden and Peeso drills.

    PubMed

    Lausten, L L; Luebke, N H; Brantley, W A

    1993-09-01

    A laboratory study was performed on Gates Glidden and Peeso drills to determine the bending characteristics and related metallurgical properties. Sizes #1 to #6 stainless steel Gates Glidden drills, sizes #1 to #6 stainless steel and carbon steel type P Peeso drills, and sizes #009 to #023 carbon steel-type B-1 Peeso drills were evaluated in cantilever bending with a Tinius Olsen stiffness tester. The bending moments were measured for a 12.5-mm test span at deflection angles of 2 to 90 degrees. The mean maximum bending moments in g cm and the corresponding deflection angles in degrees were plotted graphically to ascertain the bending characteristics of the instruments. The stainless steel Gates Glidden and Peeso drills exhibited considerable permanent bending deformation during testing. Some stainless steel drill samples were able to withstand the full bending deflection of 90 degrees without fracturing. In contrast, the carbon steel Peeso drills were able only to undergo bending deflections of less than 20 degrees and exhibited brittle fracture. If the drill fractured during the in vitro testing, the failure site was always located near the handpiece end.

  8. Hyperbaric oxygen therapy as a treatment for stage-I avascular necrosis of the femoral head.

    PubMed

    Reis, N D; Schwartz, O; Militianu, D; Ramon, Y; Levin, D; Norman, D; Melamed, Y; Shupak, A; Goldsher, D; Zinman, C

    2003-04-01

    Avascular necrosis (AVN) of the head of the femur is a potentially crippling disease which mainly affects young adults. Although treatment by exposure to hyperbaric oxygen (HBO) is reported as being beneficial, there has been no study of its use in treated compared with untreated patients. We selected 12 patients who suffered from Steinberg stage-I AVN of the head of the femur (four bilateral) whose lesions were 4 mm or more thick and/or 12.5 mm or more long on MRI. Daily HBO therapy was given for 100 days to each patient. All smaller stage-I lesions and more advanced stages of AVN were excluded. These size criteria were chosen in order to compare outcomes with an identical size of lesion in an untreated group described earlier. Overall, 81% of patients who received HBO therapy showed a return to normal on MRI as compared with 17% in the untreated group. We therefore conclude that hyperbaric oxygen is effective in the treatment of stage-I AVN of the head of the femur.

  9. Amperometric Sensor for Detection of Chloride Ions†

    PubMed Central

    Trnkova, Libuse; Adam, Vojtech; Hubalek, Jaromir; Babula, Petr; Kizek, Rene

    2008-01-01

    Chloride ion sensing is important in many fields such as clinical diagnosis, environmental monitoring and industrial applications. We have measured chloride ions at a carbon paste electrode (CPE) and at a CPE modified with solid AgNO3, a solution of AgNO3 and/or solid silver particles. Detection limits (3 S/N) for chloride ions were 100 μM, 100 μM and 10 μM for solid AgNO3, solution of AgNO3 and/or solid silver particles, respectively. The CPE modified with silver particles is the most sensitive to the presence chloride ions. After that we approached to the miniaturization of the whole electrochemical instrument. Measurements were carried out on miniaturized instrument consisting of a potentiostat with dimensions 35 × 166 × 125 mm, screen printed electrodes, a peristaltic pump and a PC with control software. Under the most suitable experimental conditions (Britton-Robinson buffer, pH 1.8 and working electrode potential 550 mV) we estimated the limit of detection (3 S/N) as 500 nM. PMID:27873832

  10. Suture-free laser-assisted vessel repair using CO2 laser and liquid albumin solder.

    PubMed

    Wolf-de Jonge, Ingrid C D Y M; Heger, Michal; van Marle, Jan; Balm, Ron; Beek, Johan F

    2008-01-01

    Numerous studies have shown that the use of proteinic solders during laser-assisted vascular anastomosis (LAVA) and repair (LAVR) can significantly increase welding strength, but these studies combined solder-mediated LAVA/R with the use of stay sutures, thereby defeating its purpose. In an in vitro study, we examined the leaking point pressures (LPPs) and histological damage profile of porcine carotid arteries following albumin solder-mediated CO(2) LAVR without the use of sutures. Longitudinal arteriotomies (9.1+/-0.8 mm in length) were sheathed with 25% liquid bovine serum albumin solder, and LAVR was performed using a micromanipulator-controlled CO(2) laser operating at 170-mW power and 1.25-mm spot size in continuous wave mode. The welding regime consisted of a transversal zigzag pass followed by one or two longitudinal zigzag passes, producing an irradiance of 13.9 W/cm(2) and energies of 10.5 J and 11.3 J per mm weld, respectively. LPPs were measured by the fluid infusion technique, and histological analysis was performed with light, fluorescence, and polarization microscopy. The LPP of the two-pass welds was 351+/-158 mmHg versus 538+/-155 mmHg for the three-pass welds. Thermal damage was confined primarily to the adventitial layers, with limited heat diffusion into the media below the solder around the coaptation interface.

  11. Mechanisms and clinical applications of the vacuum-assisted closure (VAC) Device: a review.

    PubMed

    Venturi, Mark L; Attinger, Christopher E; Mesbahi, Ali N; Hess, Christopher L; Graw, Katherine S

    2005-01-01

    The use of sub-atmospheric pressure dressings, available commercially as the vacuum-assisted closure (VAC) device, has been shown to be an effective way to accelerate healing of various wounds. The optimal sub-atmospheric pressure for wound healing appears to be approximately 125 mm Hg utilizing an alternating pressure cycle of 5 minutes of suction followed by 2 minutes off suction. Animal studies have demonstrated that this technique optimizes blood flow, decreases local tissue edema, and removes excessive fluid from the wound bed. These physiologic changes facilitate the removal of bacteria from the wound. Additionally, the cyclical application of sub-atmospheric pressure alters the cytoskeleton of the cells in the wound bed, triggering a cascade of intracellular signals that increases the rate of cell division and subsequent formation of granulation tissue. The combination of these mechanisms makes the VAC device an extremely versatile tool in the armamentarium of wound healing. This is evident in the VAC device's wide range of clinical applications, including treatment of infected surgical wounds, traumatic wounds, pressure ulcers, wounds with exposed bone and hardware, diabetic foot ulcers, and venous stasis ulcers. VAC has also proven useful in reconstruction of wounds by allowing elective planning of the definitive reconstructive surgery without jeopardizing the wound or outcome. Furthermore, VAC has significantly increased the skin graft success rate when used as a bolster over the freshly skin-grafted wound. VAC is generally well tolerated and, with few contraindications or complications, is fast becoming a mainstay of current wound care.

  12. Prediction of the mid-tracheal level using surface anatomical landmarks in adults

    PubMed Central

    Jang, Young-Eun; Kim, Eun-Hee; Song, In-Kyung; Lee, Ji-Hyun; Ryu, Ho-Geoul; Kim, Hee-Soo; Kim, Jin-Tae

    2017-01-01

    Abstract Endotracheal tube (ETT) should be placed at the optimal level to avoid single lung ventilation or accidental extubation. This study was performed to estimate the mid-tracheal level by using surface anatomical landmarks in adult patients. Neck computed tomography images of 329 adult patients between the ages of 16 and 79 years were reviewed. In the midline sagittal plane, the levels corresponding to the vocal cords, cricoid cartilage, suprasternal notch, manubriosternal junction, and carina were identified. The surface distances from the cricoid cartilage to the suprasternal notch (extCC-SSN) and that from the suprasternal notch to the manubriosternal junction (extSSN-MSJ) were measured. The relationship between mid-tracheal level and the surface distances was analyzed using Bland–Altman plot. The difference between the extCC-SSN and the mid-tracheal level was −6.6 (12.5) mm, and the difference between the extSSN-MSJ and the mid-tracheal level was −19.2 (6.1) mm. The difference between the extCC-SSN and the mid-tracheal level was smaller in females compared with males [−1.7 (11.7) mm vs −12.8 (10.7) mm; P < 0.001]. The mid-tracheal level, which is helpful in planning the insertion depth of an ETT, can be predicted by the surface distance between the cricoid cartilage and suprasternal notch in adults, especially in females. PMID:28328810

  13. Compact turnkey focussing neutron guide system for inelastic scattering investigations

    NASA Astrophysics Data System (ADS)

    Brandl, G.; Georgii, R.; Dunsiger, S. R.; Tsurkan, V.; Loidl, A.; Adams, T.; Pfleiderer, C.; Böni, P.

    2015-12-01

    We demonstrate the performance of a compact neutron guide module which boosts the intensity in inelastic neutron scattering experiments by approximately a factor of 40. The module consists of two housings containing truly curved elliptic focussing guide elements, positioned before and after the sample. The advantage of the module lies in the ease with which it may be reproducibly mounted on a spectrometer within a few hours, on the same timescale as conventional sample environments. It is particularly well suited for samples with a volume of a few mm3, thus enabling the investigation of materials which to date would have been considered prohibitively small or samples exposed to extreme environments, where there are space constraints. We benchmark the excellent performance of the module by measurements of the structural and magnetic excitations in single crystals of model systems. In particular, we report the phonon dispersion in the simple element lead. We also determine the magnon dispersion in the spinel ZnCr2Se4 (V = 12.5 mm3), where strong magnetic diffuse scattering at low temperatures evolves into distinct helical order.

  14. A technical note on diluting semen for the haemocytometric determination of sperm concentration.

    PubMed

    Mortimer, D; Shu, M A; Tan, R; Mortimer, S T

    1989-02-01

    A comparison was made of the use of either an SMI positive displacement pipette or an Eppendorf Varipette as the method of sampling 63 liquefied semen samples for volumetric dilution and haemocytometry to determine sperm concentration. The 95% range of the differences between the values obtained using the SMI and the Varipette with whole tips was from -46.9 to 63.8 x 10(6)/ml. With the Varipette tips cut off 12.5 mm from the end the 95% range was from -52.4 to 55.8 x 10(6)/ml. Previous work had shown that the 95% ranges of differences between duplicate determinations using the SMI pipette were from -7.2 to 6.9 x 10(6)/ml for two 1 + 19 dilutions, or from -16.0 to 12.1 x 10(6)/ml for 1 + 19 and 1 + 49 parallel dilutions. Therefore, since the Varipette had a far greater potential for error, a positive displacement pipette should be used when taking precise volume aliquots of human semen.

  15. Single-element PV and PC infrared detectors for medical applications

    NASA Astrophysics Data System (ADS)

    Kim, Young-Ho; Han, Myung-Soo; Jeoung, Min-Suk; Yim, Nam-Su; Hahn, Suk-Ryong

    2001-11-01

    In Korea, Japan and China, the measurement of surface temperature profile shown in abnormalities in neural and vascular functions, facial lesions, changes of blood stream in peripheral tissues (breast cancer, etc.), and psychosomatic problems is widely used for the diagnosis and the progress monitor of disease and symptoms (pains). For this application, single element LWIR Hg0.78Cd0.22Te photo-conductive (PC) detectors were fabricated with the wafers having a cutoff wavelength larger than 12.5 mm. The optical characteristics such as responsivity and detectivity were tested and the operation of the detectors was proved by the thermal imaging system IRIS5000. It was found that the 1/f noise makes lines and seriously degrades the thermal images. MWIR Hg0.70Cd0.30Te photo-voltaic (PV) detectors were also fabricated and tested for the medical application. However, owing to the low signal, the results were far from satisfactory. It is supposed that the integration methods are required for the single element MWIR detector.

  16. Simultaneous HPLC determination of ketoprofen and its degradation products in the presence of preservatives in pharmaceuticals.

    PubMed

    Dvorák, J; Hájková, R; Matysová, L; Nováková, L; Koupparis, M A; Solich, P

    2004-11-15

    A novel and quick high-performance liquid chromatography (HPLC) method with UV spectrophotometric detection was developed and validated for the determination of five compounds in topical gel. The described method is suitable for simultaneous determination of active component ketoprofen, two preservatives methylparaben and propylparaben and two degradation products of ketoprofen--3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid--in a topical cream after long-term stability tests using ethylparaben as an internal standard. The chromatographic separation was performed on a 5microm Supelco Discovery C18 column (125mm x 4mm i.d., Sigma-Aldrich); the optimal mobile phase for separation of ketoprofen, methylparaben, propylparaben, degradation products 3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid and ethylparaben as internal standard consists of a mixture of acetonitril, water and phosphate buffer pH 3.5 (40:58:2, v/v/v). At a flow rate of 1.0ml min(-1) and detection at 233nm, the total time of analysis was less than 10min. The method was applied for routine analysis (batch analysis and stability tests) of these compounds in topical pharmaceutical product.

  17. An evaluation of the shielding effectiveness of lead aprons used in clinics for protection against ionising radiation from novel radioisotopes.

    PubMed

    Deb, Pradip; Jamison, Robert; Mong, Lisa; U, Paul

    2015-07-01

    The purpose of this study is to evaluate the effectiveness of personal radiation shields currently worn in hospital and other diagnostic environments. This study was performed with four different radioisotopes; (18)F, (99m)Tc, (124)I and (131)I. (18)F results showed a decrease in dose with 0.5-mm Pb shielding but the reduction provided does not warrant its use clinically. (124)I testing demonstrated that dose enhancement can occur in greater shield thicknesses. PET isotope (124)I can be adequately shielded using 0.25-mm Pb equivalent aprons but any higher thickness increase the wearer's dose. As a result more shielding does not always equal more protection. The (131)I test showed that no dose reduction occurred, even when tested with up to 1.25-mm Pb equivalent shielding. Novel radioisotopes being used in the laboratory and clinic should be individually tested as each requires specific shielding testing. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Effect of Layer Thickness and Printing Orientation on Mechanical Properties and Dimensional Accuracy of 3D Printed Porous Samples for Bone Tissue Engineering

    PubMed Central

    Farzadi, Arghavan; Solati-Hashjin, Mehran; Asadi-Eydivand, Mitra; Abu Osman, Noor Azuan

    2014-01-01

    Powder-based inkjet 3D printing method is one of the most attractive solid free form techniques. It involves a sequential layering process through which 3D porous scaffolds can be directly produced from computer-generated models. 3D printed products' quality are controlled by the optimal build parameters. In this study, Calcium Sulfate based powders were used for porous scaffolds fabrication. The printed scaffolds of 0.8 mm pore size, with different layer thickness and printing orientation, were subjected to the depowdering step. The effects of four layer thicknesses and printing orientations, (parallel to X, Y and Z), on the physical and mechanical properties of printed scaffolds were investigated. It was observed that the compressive strength, toughness and Young's modulus of samples with 0.1125 and 0.125 mm layer thickness were more than others. Furthermore, the results of SEM and μCT analyses showed that samples with 0.1125 mm layer thickness printed in X direction have more dimensional accuracy and significantly close to CAD software based designs with predefined pore size, porosity and pore interconnectivity. PMID:25233468

  19. An intrinsic fiber-optic single loop micro-displacement sensor.

    PubMed

    Martinez-Rios, Alejandro; Monzon-Hernandez, David; Torres-Gomez, Ismael; Salceda-Delgado, Guillermo

    2012-01-01

    A micro-displacement sensor consisting of a fiber-loop made with a tapered fiber is reported. The sensor operation is based on the interaction between the fundamental cladding mode propagating through the taper waist and higher order cladding modes excited when the taper is deformed to form a loop. As a result, a transmission spectrum with several notches is observed, where the notch wavelength resonances shift as a function of the loop diameter. The loop diameter is varied by the spatial displacement of one end of the fiber-loop attached to a linear translation stage. In a displacement range of 3.125 mm the maximum wavelength shift is 360.93 nm, with 0.116 nm/μm sensitivity. By using a 1,280 nm broadband low-power LED source and a single Ge-photodetector in a power transmission sensor setup, a sensitivity in the order of 2.7 nW/μm is obtained in ≈ 1 mm range. The proposed sensor is easy to implement and has a plenty of room to improve its performance.

  20. 16 MHz wavelength-swept and wavelength-stepped laser architectures based on stretched-pulse active mode locking with a single continuously chirped fiber Bragg grating

    PubMed Central

    Khazaeinezhad, Reza; Siddiqui, Meena; Vakoc, Benjamin J.

    2017-01-01

    We demonstrate a novel high-speed and broadband laser architecture based on stretched pulse active mode locking that provides a wavelength-swept and wavelength-stepped output. The laser utilizes a single intracavity 8.3 meter chirped fiber Bragg grating to generate positive and negative dispersion, and can be operated with or without an intracavity fixed Fabry–Perot etalon to generate wavelength-swept and wavelength-stepped (frequency comb) outputs, respectively. Using a four-path delay line at the output, we achieved 16.3MHz repetition rates and a 62 nm lasing bandwidth centered at 1550 nm. Single-sided double-pass coherence lengths of 1.25 mm for the wavelength-swept configuration and more than 30 mm for the wavelength-stepped configuration were obtained. Relative intensity noise was measured to be better than −140 dB/Hz. The stretched-pulse mode-locked architecture utilizing long chirped fiber Bragg gratings offers a simple and compact design for a broadband wavelength-tuned output at unprecedented speeds, and can address the need for fast sources in applications such as optical ranging, imaging, and sensing. PMID:28504745

  1. Some observations on cyclic deformation structures in the high-strength commercial aluminum alloy AA 7150

    SciTech Connect

    Hanlon, D.N.; Rainforth, W.M.

    1998-11-01

    Load-controlled fatigue testing of the aluminum alloy AA 7150 has been conducted using four-point bending with an R ratio of + 0.1 over a range of maximum stress levels from 60 to 120% of the 0.2% proof stress. The alloy, in the form of 12.5-mm rolled plate, was investigated in underaged (UA), peak-aged (PA), and overaged (OA) conditions, corresponding to a change in average precipitate sizes from 5 nm in the UA condition to 21 nm in the OA condition. Three orientations of the plate were investigated. Orientation and aging condition influenced the degree of surface topographical development but not fatigue life. Detailed transmission electron microscopy (TEM) of the fatigued surface indicated that deformation in all aging conditions occurred by planar slip. Slip was generally restricted to a single slip system within each grain, and subgrain boundaries offered little resistance to dislocation movement facilitating long slip line lengths (measured up to 310 {micro}m) between adjacent high-angle grain boundaries. Planar slip observed in the OA condition is attributed to shearing of large strengthening precipitates, which is promoted by long slip line lengths. No evidence of surface specific changes in slip character was observed.

  2. GEM-type detectors using LIGA and etchable glass technologies

    SciTech Connect

    Ahn, S.K.; Kim, J.G.; Perez-Mendez, V.; Chang, S.; Jackson, K.H.; Kadyk, J.A.; Wenzel, W.A.; Cho, G.

    2001-11-02

    Gas electron multipliers (GEMS) have been made by a deep X-ray lithography technique (LIGA process) using synchrotron radiation on polymethylmethacrylate (PMMA) and by UV processes using a UV etchable glass. Gain, stability and rate capability for these detectors are described.The LIGA detectors described consist of PMMA sheets of various thicknesses, 125mm to 350mm, and have 150mm x 150mm square holes spaced with a pitch of 300mm. Thin copper electrodes are plated on the top and bottom surfaces using a Damascene method, followed by electroless plating of the copper onto a palladium-tin base layer. For various thicknesses of PMMA measurements have been made of absolute gain vs. voltage, time stability of gain, and rate capability. The operating gas mixture was usually Ar/CO2 (70/30) gas, but some tests were also done using P10 gas. We also made GEM-like detectors using the UV etchable glass called Foturan, patterned by exposure to UV light and subsequent etching. A few measurements using these detectors will be reported, including avalanche gain and time stability.

  3. Multi-limb acquisition of motor evoked potentials and its application in spinal cord injury.

    PubMed

    Iyer, Shrivats; Maybhate, Anil; Presacco, Alessandro; All, Angelo H

    2010-11-30

    The motor evoked potential (MEP) is an electrical response of peripheral neuro-muscular pathways to stimulation of the motor cortex. MEPs provide objective assessment of electrical conduction through the associated neural pathways, and therefore detect disruption due to a nervous system injury such as spinal cord injury (SCI). In our studies of SCI, we developed a novel, multi-channel set-up for MEP acquisition in rat models. Unlike existing electrophysiological systems for SCI assessment, the set-up allows for multi-channel MEP acquisition from all limbs of rats and enables longitudinal monitoring of injury and treatment for in vivo models of experimental SCI. The article describes the development of the set-up and discusses its capabilities to acquire MEPs in rat models of SCI. We demonstrate its use for MEP acquisition under two types of anesthesia as well as a range of cortical stimulation parameters, identifying parameters yielding consistent and reliable MEPs. To validate our set-up, MEPs were recorded from a group of 10 rats before and after contusive SCI. Upon contusion with moderate severity (12.5mm impact height), MEP amplitude decreased by 91.36±6.03%. A corresponding decline of 93.8±11.4% was seen in the motor behavioral score (BBB), a gold standard in rodent models of SCI. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Preparation and characterization of carbonyl iron/glass composite absorber as matched load for isolator

    NASA Astrophysics Data System (ADS)

    Feng, Yongbao; Li, Yujiao; Qiu, Tai

    2012-09-01

    Composite absorbers made from 66 wt% carbonyl iron and 34 wt% low melting point glass powder were prepared by a pressureless sintering technique in a nitrogen atmosphere. Apparent porosity and bending strength of the as-prepared composites were investigated. The microstructure, heat resisting properties and electromagnetic properties were characterized by scanning electron microscopy, thermal gravimetric analysis-differential scanning calorimetry and vector network analyzer. The results show that the carbonyl iron/glass composite absorbers were difficult to densify. As the sintering temperature and soaking time increased, the apparent porosity first decreased and then increased, whereas the bending strength showed the opposite change. The composite absorber sintered at 520 °C for 40 min achieved the minimum apparent porosity of 13.08% and the highest bending strength of 52 MPa. Compared to the carbonyl iron/silicone rubber absorber, the carbonyl iron/glass composite absorber exhibited better heat resisting properties, and the initial oxidation temperature was increased about 200 °C. The composite absorber with a thickness of 1.25 mm showed a good microwave absorbing property in 8-12 GHz.

  5. The Solanum lycopersicum Zinc Finger2 cysteine-2/histidine-2 repressor-like transcription factor regulates development and tolerance to salinity in tomato and Arabidopsis.

    PubMed

    Hichri, Imène; Muhovski, Yordan; Žižkova, Eva; Dobrev, Petre I; Franco-Zorrilla, Jose Manuel; Solano, Roberto; Lopez-Vidriero, Irene; Motyka, Vaclav; Lutts, Stanley

    2014-04-01

    The zinc finger superfamily includes transcription factors that regulate multiple aspects of plant development and were recently shown to regulate abiotic stress tolerance. Cultivated tomato (Solanum lycopersicum Zinc Finger2 [SIZF2]) is a cysteine-2/histidine-2-type zinc finger transcription factor bearing an ERF-associated amphiphilic repression domain and binding to the ACGTCAGTG sequence containing two AGT core motifs. SlZF2 is ubiquitously expressed during plant development, and is rapidly induced by sodium chloride, drought, and potassium chloride treatments. Its ectopic expression in Arabidopsis (Arabidopsis thaliana) and tomato impaired development and influenced leaf and flower shape, while causing a general stress visible by anthocyanin and malonyldialdehyde accumulation. SlZF2 enhanced salt sensitivity in Arabidopsis, whereas SlZF2 delayed senescence and improved tomato salt tolerance, particularly by maintaining photosynthesis and increasing polyamine biosynthesis, in salt-treated hydroponic cultures (125 mm sodium chloride, 20 d). SlZF2 may be involved in abscisic acid (ABA) biosynthesis/signaling, because SlZF2 is rapidly induced by ABA treatment and 35S::SlZF2 tomatoes accumulate more ABA than wild-type plants. Transcriptome analysis of 35S::SlZF2 revealed that SlZF2 both increased and reduced expression of a comparable number of genes involved in various physiological processes such as photosynthesis, polyamine biosynthesis, and hormone (notably ABA) biosynthesis/signaling. Involvement of these different metabolic pathways in salt stress tolerance is discussed.

  6. Strong upstream flow characteristics in the formation of rivulets

    NASA Astrophysics Data System (ADS)

    Lye, Jonathan Kok Keung; Neild, Adrian; Ng, Tuck Wah

    2011-02-01

    In a fully formed rivulet, the flow profile across the total cross section is downward, as would be intuitively expected. However, prior to this stage being reached, a strong backflow capable of carrying particles up to 125 mm up the incline back to the source is shown to occur. Two phases are described prior to a fully formed rivulet being established. First, a forming rivulet, in which a bulbous drop head slides down a slope with a flow occurring in the wetted trail behind it. In this stage, a linear increase in backflow height is observed over time. Subsequently, a transient rivulet occurs, with the transition happening once the end of the inclined solid surface is reached. The backflow decreases through this phase in a stepwise manner, coinciding with fluid dripping off the surface. The findings here strongly challenge common assumptions made regarding cleaning, whereby fluid will transport particulate matter downhill, and has significant implications on irrigation applied to remove bacterial biofilms in clinical medicine.

  7. A field study of virus removal in septic tank drainfields.

    PubMed

    Nicosia, L A; Rose, J B; Stark, L; Stewart, M T

    2001-01-01

    Two field studies were conducted at a research station in Tampa, Florida to assess the removal of bacteriophage PRD1 from wastewater in septic tank drainfields. Infiltration cells were seeded with PRD1 and bromide and the effects of effluent hydraulic loading rate and rainfall on virus removal were monitored. Septic tank effluent samples were collected after passage through 0.6 m of unsaturated fine sand and PRD1 was detected over an average of 67 d. Bacteriophage PRD1 breakthrough was detected at approximately the same time as bromide in all three cells except for the low-load cell (Study 1), where bromide was never detected. Log10 removals of PRD1 were 1.43 and 1.91 for the high-load cells (hydraulic loading rate = 0.063 m/d) and 2.21 for the low-load cell (hydraulic loading rate = 0.032 m/d). Virus attenuation is attributed to dispersion, dilution, and inactivation. Significant increases in PRD1 elution with rainfall were observed in the first 10 d of the study. Approximately 125 mm of rainfall caused a 1.2 log10 increase of PRD1 detected at the 0.6-m depth. Current Florida onsite wastewater disposal standards, which specify a 0.6-m distance from the drainfield to the water table, may not provide sufficient removal of viruses, particularly during the wet season.

  8. Quarry blasts assessment and their environmental impacts on the nearby oil pipelines, southeast of Helwan City, Egypt

    NASA Astrophysics Data System (ADS)

    Mohamed, Adel M. E.; Mohamed, Abuo El-Ela A.

    2013-06-01

    Ground vibrations induced by blasting in the cement quarries are one of the fundamental problems in the quarrying industry and may cause severe damage to the nearby utilities and pipelines. Therefore, a vibration control study plays an important role in the minimization of environmental effects of blasting in quarries. The current paper presents the influence of the quarry blasts at the National Cement Company (NCC) on the two oil pipelines of SUMED Company southeast of Helwan City, by measuring the ground vibrations in terms of Peak Particle Velocity (PPV). The seismic refraction for compressional waves deduced from the shallow seismic survey and the shear wave velocity obtained from the Multi channel Analysis of Surface Waves (MASW) technique are used to evaluate the closest site of the two pipelines to the quarry blasts. The results demonstrate that, the closest site of the two pipelines is of class B, according to the National Earthquake Hazard Reduction Program (NEHRP) classification and the safe distance to avoid any environmental effects is 650 m, following the deduced Peak Particle Velocity (PPV) and scaled distance (SD) relationship (PPV = 700.08 × SD-1.225) in mm/s and the Air over Pressure (air blast) formula (air blast = 170.23 × SD-0.071) in dB. In the light of prediction analysis, the maximum allowable charge weight per delay was found to be 591 kg with damage criterion of 12.5 mm/s at the closest site of the SUMED pipelines.

  9. A laboratory evaluation of tagging-related mortality and tag loss in juvenile humpback chub

    USGS Publications Warehouse

    Ward, David L.; Persons, William R.; Young, Kirk; Stone, Dennis M.; Van Haverbeke, Randy; Knight, William R.

    2015-01-01

    We quantified tag retention, survival, and growth in juvenile, captive-reared Humpback Chub Gila cypha marked with three different tag types: (1) Biomark 12.5-mm, 134.2-kHz, full duplex PIT tags injected into the body cavity with a 12-gauge needle; (2) Biomark 8.4-mm, 134.2-kHz, full duplex PIT tags injected with a 16-gauge needle; and (3) Northwest Marine Technology visible implant elastomer (VIE) tags injected under the skin with a 29-gauge needle. Estimates of tag loss, tagging-induced mortality, and growth were evaluated for 60 d with each tag type for four different size-groups of fish: 40–49 mm, 50–59 mm, 60–69 mm, and 70–79 mm TL. Total length was a significant predictor of the probability of PIT tag retention and mortality for both 8-mm and 12-mm PIT tags, and the smallest fish had the highest rates of tag loss (12.5–30.0%) and mortality (7.5–20.0%). Humpback Chub of sizes 40–49 mm TL and tagged with VIE tags had no mortality but did have a 17.5% tag loss. Growth rates of all tagged fish were similar to controls. Our data indicate Humpback Chub can be effectively tagged using either 8-mm or 12-mm PIT tags with little tag loss or mortality at sizes as low as 65 mm TL.

  10. Smaller cerebral aneurysms producing more extensive subarachnoid hemorrhage following rupture: a radiological investigation and discussion of theoretical determinants.

    PubMed

    Russell, Stephen M; Lin, Ke; Hahn, Sigrid A; Jafar, Jafar J

    2003-08-01

    The goal of this study was to determine the relationship between aneurysm size and the volume of subarachnoid hemorrhage (SAH). One hundred consecutive patients who presented with acute SAH, which was diagnosed on the basis of a computerized tomography (CT) scan within 24 hours postictus and, subsequently, confirmed to be aneurysmal in origin by catheter angiography, were included in this study. The data were collected prospectively in 32 patients and retrospectively in 68. The volume of SAH on the admission CT scan was scored in a semiquantitative manner from 0 to 30, according to a previously published method. The mean aneurysm size was 8.3 mm (range 1-25 mm). The mean SAH volume score was 15 (range 0-30). Regression analysis revealed that a smaller aneurysm size correlated with a more extensive SAH (r(2) = 0.23, p < 0.0001). Other variables including patient sex and age, intraparenchymal or intraventricular hemorrhage, multiple aneurysms, history of hypertension, and aneurysm location were not statistically associated with a larger volume of SAH. Smaller cerebral aneurysm size is associated with a larger volume of SAH. The pathophysiological basis for this correlation remains speculative.

  11. An experimental study of solid source diffusion by spin on dopants and its application for minimal silicon-on-insulator CMOS fabrication

    NASA Astrophysics Data System (ADS)

    Liu, Yongxun; Koga, Kazuhiro; Khumpuang, Sommawan; Nagao, Masayoshi; Matsukawa, Takashi; Hara, Shiro

    2017-06-01

    Solid source diffusions of phosphorus (P) and boron (B) into the half-inch (12.5 mm) minimal silicon (Si) wafers by spin on dopants (SOD) have been systematically investigated and the physical-vapor-deposited (PVD) titanium nitride (TiN) metal gate minimal silicon-on-insulator (SOI) complementary metal-oxide-semiconductor (CMOS) field-effect transistors (FETs) have successfully been fabricated using the developed SOD thermal diffusion technique. It was experimentally confirmed that a low temperature oxidation (LTO) process which depresses a boron silicide layer formation is effective way to remove boron-glass in a diluted hydrofluoric acid (DHF) solution. It was also found that top Si layer thickness of SOI wafers is reduced in the SOD thermal diffusion process because of its consumption by thermal oxidation owing to the oxygen atoms included in SOD films, which should be carefully considered in the ultrathin SOI device fabrication. Moreover, normal operations of the fabricated minimal PVD-TiN metal gate SOI-CMOS inverters, static random access memory (SRAM) cells and ring oscillators have been demonstrated. These circuit level results indicate that no remarkable particles and interface traps were introduced onto the minimal wafers during the device fabrication, and the developed solid source diffusion by SOD is useful for the fabrication of functional logic gate minimal SOI-CMOS integrated circuits.

  12. Hydrogen attack - Influence of hydrogen sulfide. [on carbon steel

    NASA Technical Reports Server (NTRS)

    Eliezer, D.; Nelson, H. G.

    1978-01-01

    An experimental study is conducted on 12.5-mm-thick SAE 1020 steel (plain carbon steel) plate to assess hydrogen attack at room temperature after specimen exposure at 525 C to hydrogen and a blend of hydrogen sulfide and hydrogen at a pressure of 3.5 MN/sq m for exposure times up to 240 hr. The results are discussed in terms of tensile properties, fissure formation, and surface scales. It is shown that hydrogen attack from a high-purity hydrogen environment is severe, with the formation of numerous methane fissures and bubbles along with a significant reduction in the room-temperature tensile yield and ultimate strengths. However, no hydrogen attack is observed in the hydrogen/hydrogen sulfide blend environment, i.e. no fissure or bubble formation occurred and the room-temperature tensile properties remained unchanged. It is suggested that the observed porous discontinuous scale of FeS acts as a barrier to hydrogen entry, thus reducing its effective equilibrium solubility in the iron lattice. Therefore, hydrogen attack should not occur in pressure-vessel steels used in many coal gasification processes.

  13. Quality control for blood pressure measurement in population studies: Shibata Children's Heart Study.

    PubMed

    Yoshiike, N; Nakayama, T; Yokoyama, T; Tanaka, H; Labarthe, D R

    1997-10-01

    To investigate the relation between observer performance for blood pressure measurement in a training process and in field conditions, measurement values were studied under training and field conditions among 21 blood pressure observers of 1434 subjects aged 6-15 years in Japan. The observers received training by a videotape, which included six audiovisual presentations of a falling mercury column in a standard sphygmomanometer with Korotkoff sounds. Observer bias was measured for each trainee as the mean difference between the observed and the standard values for each blood pressure reading, including systolic (SBP), fourth-phase diastolic (K4), and fifth-phase diastolic (K5) values. In multiple linear regression analyses, each 1 mmHg increment in observer bias was equivalent to 1.27, 0.88, and 1.25 mmHg difference in actual readings of SBP, K4, and K5, respectively, in the field. This finding indicates that observer performance in videotape training is predictive of measurement behavior in the field.

  14. Electro-Mechanical Simulation of a Large Aperture MOEMS Fabry-Perot Tunable Filter

    NASA Technical Reports Server (NTRS)

    Kuhn, Jonathan L.; Barclay, Richard B.; Greenhouse, Matthew A.; Mott, D. Brent; Satyapal, Shobita; Powers, Edward I. (Technical Monitor)

    2000-01-01

    We are developing a micro-machined electrostatically actuated Fabry-Perot tunable filter with a large clear aperture for application in high through-put wide-field imaging spectroscopy and lidar systems. In the first phase of this effort, we are developing key components based on coupled electro-mechanical simulations. In particular, the movable etalon plate design leverages high coating stresses to yield a flat surface in drum-head tension over a large diameter (12.5 mm). In this approach, the cylindrical silicon movable plate is back etched, resulting in an optically coated membrane that is suspended from a thick silicon support ring. Understanding the interaction between the support ring, suspended membrane, and coating is critical to developing surfaces that are flat to within stringent etalon requirements. In this work, we present the simulations used to develop the movable plate, spring suspension system, and electrostatic actuation mechanism. We also present results from tests of fabricated proof of concept components.

  15. A Novel Differential Time-of-Arrival Estimation Technique for Impact Localization on Carbon Fiber Laminate Sheets.

    PubMed

    Merlo, Eugenio Marino; Bulletti, Andrea; Giannelli, Pietro; Calzolai, Marco; Capineri, Lorenzo

    2017-10-03

    Composite material structures are commonly used in many industrial sectors (aerospace, automotive, transportation), and can operate in harsh environments where impacts with other parts or debris may cause critical safety and functionality issues. This work presents a method for improving the accuracy of impact position determination using acoustic source triangulation schemes based on the data collected by piezoelectric sensors attached to the structure. A novel approach is used to estimate the Differential Time-of-Arrival (DToA) between the impact response signals collected by a triplet of sensors, overcoming the limitations of classical methods that rely on amplitude thresholds calibrated for a specific sensor type. An experimental evaluation of the proposed technique was performed with specially made circular piezopolymer (PVDF) sensors designed for Structural Health Monitoring (SHM) applications, and compared with commercial piezoelectric SHM sensors of similar dimensions. Test impacts at low energies from 35 mJ to 600 mJ were generated in a laboratory by free-falling metal spheres on a 500 mm × 500 mm × 1.25 mm quasi-isotropic Carbon Fiber Reinforced Polymer (CFRP) laminate plate. From the analysis of many impact signals, the resulting localization error was improved for all types of sensors and, in particular, for the circular PVDF sensor an average error of 20.3 mm and a standard deviation of 8.9 mm was obtained.

  16. Selective spectroscopic imaging of hyperpolarized pyruvate and its metabolites using a single-echo variable phase advance method in balanced SSFP

    PubMed Central

    Varma, Gopal; Wang, Xiaoen; Vinogradov, Elena; Bhatt, Rupal S.; Sukhatme, Vikas; Seth, Pankaj; Lenkinski, Robert E.; Alsop, David C.; Grant, Aaron K.

    2015-01-01

    Purpose In balanced steady state free precession (bSSFP), the signal intensity has a well-known dependence on the off-resonance frequency, or, equivalently, the phase advance between successive radiofrequency (RF) pulses. The signal profile can be used to resolve the contributions from the spectrally separated metabolites. This work describes a method based on use of a variable RF phase advance to acquire spatial and spectral data in a time-efficient manner for hyperpolarized 13C MRI. Theory and Methods The technique relies on the frequency response from a bSSFP acquisition to acquire relatively rapid, high-resolution images that may be reconstructed to separate contributions from different metabolites. The ability to produce images from spectrally separated metabolites was demonstrated in-vitro, as well as in-vivo following administration of hyperpolarized 1-13C pyruvate in mice with xenograft tumors. Results In-vivo images of pyruvate, alanine, pyruvate hydrate and lactate were reconstructed from 4 images acquired in 2 seconds with an in-plane resolution of 1.25 × 1.25mm2 and 5mm slice thickness. Conclusions The phase advance method allowed acquisition of spectroscopically selective images with high spatial and temporal resolution. This method provides an alternative approach to hyperpolarized 13C spectroscopic MRI that can be combined with other techniques such as multi-echo or fluctuating equilibrium bSSFP. PMID:26507361

  17. Analysis of passivated A-286 stainless steel surfaces for mass spectrometer inlet systems by Auger electron and X-ray photoelectron spectroscopy and scanning electron microscopy

    SciTech Connect

    Ajo, Henry; Blankenship, Donnie; Clark, Elliot

    2014-07-25

    In this study, various commercially available surface treatments are being explored for use on stainless steel components in mass spectrometer inlet systems. Type A-286 stainless steel coupons, approximately 12.5 mm in diameter and 3 mm thick, were passivated with one of five different surface treatments; an untreated coupon served as a control. The surface and near-surface microstructure and chemistry of the coupons were investigated using sputter depth profiling using Auger electron spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy (SEM). All the surface treatments studied appeared to change the surface morphology dramatically, as evidenced by lack of tool marks on the treated samples in SEM images. In terms of the passivation treatment, Vendors A-D appeared to have oxide layers that were very similar in thickness to each other (0.7–0.9 nm thick), as well as to the untreated samples (the untreated sample oxide layers appeared to be somewhat larger). Vendor E’s silicon coating appears to be on the order of 200 nm thick.

  18. Meristem fate and bulbil formation in Titanotrichum (Gesneriaceae).

    PubMed

    Wang, Chun-Neng; Cronk, Quentin C B

    2003-12-01

    Titanotrichum oldhamii (a monotypic genus from Taiwan, Okinawa, and adjacent regions of China) has inflorescences bearing either showy yellow flowers or asexual bulbils. Asexual reproduction by bulbils is important in natural populations, and bulbil production increases in August and September at the end of the flowering season (which runs from June to the end of September). The bulbils are small (∼1-2.5 mm long) and numerous. They consist of a small portion of stem (bract-stem) topped by opposite storage bracts that enclose a minute apical meristem. A secondary root develops from the side of the bract-stem. The floral meristem of T. oldhamii has three possible fates: (1) bulbil formation, (2) flower formation, or (3) bracteose proliferation. Bracteose proliferation rarely occurs and appears to be a developmental transition between the bulbiliferous and racemose inflorescence forms. It is strongly reminiscent of the floricaula and squamosa mutants of Antirrhinum. In the bulbiliferous form a single floral primordium, which would normally produce one flower, gives rise to ∼50-70 bulbils by repeated subdivision of the meristem. This form of bulbil production appears to be unique to Titanotrichum. Occasionally a floral meristem divides, but the subdivision forms multiflowered units of up to four flowers rather than bulbils, suggesting that meristem fate is reversible up to the first or second meristem subdivision. In Titanotrichum, therefore, primordium fate is apparently not determined at inception but becomes irreversibly determined shortly after the appearance of developmental characteristics of the floral or bulbil pathway.

  19. Computational micromechanical analysis of the representative volume element of bituminous composite materials

    NASA Astrophysics Data System (ADS)

    Ozer, Hasan; Ghauch, Ziad G.; Dhasmana, Heena; Al-Qadi, Imad L.

    2016-08-01

    Micromechanical computational modeling is used in this study to determine the smallest domain, or Representative Volume Element (RVE), that can be used to characterize the effective properties of composite materials such as Asphalt Concrete (AC). Computational Finite Element (FE) micromechanical modeling was coupled with digital image analysis of surface scans of AC specimens. Three mixtures with varying Nominal Maximum Aggregate Size (NMAS) of 4.75 mm, 12.5 mm, and 25 mm, were prepared for digital image analysis and computational micromechanical modeling. The effects of window size and phase modulus mismatch on the apparent viscoelastic response of the composite were numerically examined. A good agreement was observed in the RVE size predictions based on micromechanical computational modeling and image analysis. Micromechanical results indicated that a degradation in the matrix stiffness increases the corresponding RVE size. Statistical homogeneity was observed for window sizes equal to two to three times the NMAS. A model was presented for relating the degree of statistical homogeneity associated with each window size for materials with varying inclusion dimensions.

  20. Performance evaluation of D-SPECT: a novel SPECT system for nuclear cardiology

    NASA Astrophysics Data System (ADS)

    Erlandsson, Kjell; Kacperski, Krzysztof; van Gramberg, Dean; Hutton, Brian F.

    2009-05-01

    D-SPECT (Spectrum Dynamics, Israel) is a novel SPECT system for cardiac perfusion studies. Based on CZT detectors, region-centric scanning, high-sensitivity collimators and resolution recovery, it offers potential advantages over conventional systems. A series of measurements were made on a β-version D-SPECT system in order to evaluate its performance in terms of energy resolution, scatter fraction, sensitivity, count rate capability and resolution. Corresponding measurements were also done on a conventional SPECT system (CS) for comparison. The energy resolution of the D-SPECT system at 140 keV was 5.5% (CS: 9.25%), the scatter fraction 30% (CS: 34%), the planar sensitivity 398 s-1 MBq-1 per head (99mTc, 10 cm) (CS: 72 s-1 MBq-1), and the tomographic sensitivity in the heart region was in the range 647-1107 s-1 MBq-1 (CS: 141 s-1 MBq-1). The count rate increased linearly with increasing activity up to 1.44 M s-1. The intrinsic resolution was equal to the pixel size, 2.46 mm (CS: 3.8 mm). The average reconstructed resolution using the standard clinical filter was 12.5 mm (CS: 13.7 mm). The D-SPECT has superior sensitivity to that of a conventional system with similar spatial resolution. It also has excellent energy resolution and count rate characteristics, which should prove useful in dynamic and dual radionuclide studies.

  1. Performance evaluation of D-SPECT: a novel SPECT system for nuclear cardiology.

    PubMed

    Erlandsson, Kjell; Kacperski, Krzysztof; van Gramberg, Dean; Hutton, Brian F

    2009-05-07

    D-SPECT (Spectrum Dynamics, Israel) is a novel SPECT system for cardiac perfusion studies. Based on CZT detectors, region-centric scanning, high-sensitivity collimators and resolution recovery, it offers potential advantages over conventional systems. A series of measurements were made on a beta-version D-SPECT system in order to evaluate its performance in terms of energy resolution, scatter fraction, sensitivity, count rate capability and resolution. Corresponding measurements were also done on a conventional SPECT system (CS) for comparison. The energy resolution of the D-SPECT system at 140 keV was 5.5% (CS: 9.25%), the scatter fraction 30% (CS: 34%), the planar sensitivity 398 s(-1) MBq(-1) per head ((99m)Tc, 10 cm) (CS: 72 s(-1) MBq(-1)), and the tomographic sensitivity in the heart region was in the range 647-1107 s(-1) MBq(-1) (CS: 141 s(-1) MBq(-1)). The count rate increased linearly with increasing activity up to 1.44 M s(-1). The intrinsic resolution was equal to the pixel size, 2.46 mm (CS: 3.8 mm). The average reconstructed resolution using the standard clinical filter was 12.5 mm (CS: 13.7 mm). The D-SPECT has superior sensitivity to that of a conventional system with similar spatial resolution. It also has excellent energy resolution and count rate characteristics, which should prove useful in dynamic and dual radionuclide studies.

  2. A contact-lens-shaped IC chip technology

    NASA Astrophysics Data System (ADS)

    Liu, Ching-Yu; Yang, Frank; Teng, Chih-Chiao; Fan, Long-Sheng

    2014-04-01

    We report on novel contact-lens-shaped silicon integrated circuit chip technology for applications such as forming a conforming retinal prosthesis. This is achieved by means of patterning thin films of high residual stress on top of a shaped thin silicon substrate. Several strategies are employed to achieve curvatures of various amounts. Firstly, high residual stress on a thin film makes a thin chip deform into a designed three-dimensional shape. Also, a series of patterned stress films and ‘petal-shaped’ chips were fabricated and analyzed. Large curvatures can also be formed and maintained by the packaging process of bonding the chips to constraining elements such as thin-film polymer ring structures. As a demonstration, a complementary metal oxide semiconductor transistor (CMOS) image-sensing retina chip is made into a contact-lens shape conforming to a human eyeball 12.5 mm in radius. This non-planar and flexible chip technology provides a desirable device surface interface to soft tissues or non-planar bio surfaces and opens up many other possibilities for biomedical applications.

  3. Effects of enriched housing on functional recovery after spinal cord contusive injury in the adult rat.

    PubMed

    Lankhorst, A J; ter Laak, M P; van Laar, T J; van Meeteren, N L; de Groot, J C; Schrama, L H; Hamers, F P; Gispen, W H

    2001-02-01

    To date, most research performed in the area of spinal cord injury focuses on treatments designed to either prevent spreading lesion (secondary injury) or to enhance outgrowth of long descending and ascending fiber tracts around or through the lesion. In the last decade, however, several authors have shown that it is possible to enhance locomotor function after spinal cord injury in both animals and patients using specific training paradigms. As a first step towards combining such training paradigms with pharmacotherapy, we evaluated recovery of function in adult rats sustaining a spinal cord contusion injury (MASCIS device, 12.5 mm at T8), either housed in an enriched environment or in standard cages (n = 15 in both groups). The animals in the enriched environment were stimulated to increase their locomotor activity by placing water and food on opposite sides of the cage. As extra stimuli, a running wheel and several other objects were added to the cage. We show that exposure to the enriched environment improves gross and fine locomotor recovery as measured by the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale, the BBB subscale, the Gridwalk, and the Thoracolumbar height test. However, no group differences were found on our electrophysiological parameters nor on the amount of spared white matter. These data justify further studies on enriched housing and more controlled exercise training, with their use as potential additive to pharmacological intervention.

  4. Size characteristics of stones ingested by common loons

    USGS Publications Warehouse

    Franson, J. Christian; Hansen, Scott P.; Pokras, Mark; Miconi, Rose

    2001-01-01

    Common Loon (Gavia immer) carcasses recovered in New England had more stones of greater combined mass in their stomachs than loons from the southeastern United States. Stones retained in sieves with mesh sizes between 4.75 and 8.00 mm accounted for the greatest percentage (by mass) of grit in loon stomachs. The median longest dimension of the largest single stone in each stomach was 12.5 mm in loons from New England and 10.7 mm in loons from the southeast (maximum = 23.1 mm and 16.8 mm, respectively). A recent national proposal to restrict the use of certain fishing weights in the United States called for a ban on lead fishing sinkers of 25.4 mm or less in any dimension. Our findings suggest it is unlikely that Common Loons would ingest lead fishing weights greater than 25.4 mm in any dimension, if such ingestion was solely the result of their search for replacement stones for their stomachs. However, this does not preclude the possibility that loons may ingest larger fishing weights under other circumstances, such as the consumption of fish with attached sinkers.

  5. Calcification classifications of small nodules identified during CT lung cancer screening

    NASA Astrophysics Data System (ADS)

    Judy, Philip F.; Riva, Roberto; Kadota, Yoshiko; Jacobson, Francine L.

    2004-05-01

    The aim of this study was to determine whether radiologists are more likely to report as calcified the small nodules detected during CT lung-cancer screening, if sharper reconstruction filters are utilized. Images were reconstructed with the 2 filters used at our institution for the lung (B50f) and for the mediastinum (B30f). The 4 lung-cancer screening cases were reconstructed with 1.25-mm section thickness at 0.6-mm section increments. Using a lax criterion, 2 radiologists identified the locations of nodular features and rated the likelihood that the features were calcified. There were 302 nodules reports. More of these (57%) were reported on images reconstructed using the smooth filter. Sixty (60) reports were definitely or possibly calcified. Seventy-three percent (73%) calcification reports were from images reconstructed using B50f. There were 27 calcification reports of one of the radiologist that were classified as non-calcified by the other radiologist. Most of calcification reports (81%) of 27 reports on which radiologists disagree regarding the likelihood of calcification were from images reconstructed using B50f. Radiologists are more likely to report small nodules detected during lung-cancer screening as calcified using the sharper reconstruction filter. Whether these nodules are actually calcified or not remains a question.

  6. Extraluminal helicoidal stretch (Helixtretch): a novel method of intestinal lengthening.

    PubMed

    Dionigi, Beatrice; Brazzo, Joseph; Connors, John Patrick; Ahmed, Azra; Fisher, Jeremy G; Zurakowski, David; Fauza, Dario O

    2014-12-01

    We sought to test a novel, extraluminal method of intestinal lengthening that precludes violation of the intestinal wall. Sprague-Dawley rats (n=45) with size-matched bowel segments isolated by Roux-en-Y reconstruction were divided into three groups. Group 1 (n=14) had no further manipulations. In Groups 2 (n=12) and 3 (n=19), the isolated segment was wrapped around a length-matched device in a helicoidal fashion. In Group 2, the device consisted of plain polyurethane tubing. In Group 3, it consisted of a gradually expanding hygroscopic hydrogel (12.5mm final diameter). Euthanasia was performed at 8-21 days. Statistical analysis was by two-way ANOVA (P<0.05). Overall survival was 87% (39/45). There was a statistically significant increase in bowel length in Group 3 compared to the other two groups (P<0.001). This increase correlated with the number of helicoidal coils (P=0.018), but not with post-operative time (P>0.50). There were no significant differences in total DNA/protein ratio across the groups (P=0.65). Histologically, there was an apparent increase in the goblet cell density in Group 3. Measured extraluminal helicoidal stretch (Helixtretch) is tolerated by the intestine. Helixtretch induces bowel lengthening in a rodent model. Further analysis of this novel, minimally invasive alternative for intestinal augmentation is warranted. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Efficacy of endotoxin adsorption therapy (polymyxin B hemoperfusion) for methicillin-resistant Staphylococcus aureus toxic shock syndrome: a case report about five patients.

    PubMed

    Taniguchi, T; Sato, K; Kurita, A; Noda, T; Okajima, M

    2013-07-01

    Toxic shock syndrome (TSS), which can be life-threatening, is clinically and pathologically characterized by the presence of high fever, skin rash, desquamation, hypotension, and multiple organ failure caused by an enterotoxin produced by Staphylococcus aureus. In this study, we evaluated the effects of endotoxin adsorption therapy (polymyxin B [PMX] hemoperfusion) in critical patients with methicillin-resistant Staphylococcus aureus TSS (MRSA-TSS) who showed no improvement with the conventional therapy. Five MRSA-TSS patients (men/women: 3/2; median age: 39 years) who showed no improvement with the conventional therapy underwent PMX hemoperfusion in addition to the conventional therapy. The primary outcomes were change in the systolic arterial pressure (SAP) and requirement of a vasopressor after PMX hemoperfusion, and the secondary outcomes were change in laboratory data and sequential organ failure assessment (SOFA) scores 24 h after the therapy. The median duration of PMX hemoperfusion was 9 h (range, 4-20 h). SAP significantly increased (from 89 to 125 mmHg, P<0.05) and the requirement of a vasopressor significantly decreased (from 10 to 2, P<0.05) after PMX hemoperfusion. Furthermore, the patients' white blood cell count decreased (from 17640 to 10090 /uL, P<0.05), and SOFA scores decreased (from 13 to 9, P<0.05) after PMX hemoperfusion. All patients recovered and were discharged from the ICU. Our results showed that PMX hemoperfusion significantly improved the hemodynamics and severity in patients with life-threatening MRSA-TSS.

  8. Determination of mercurial species in fish by inductively coupled plasma mass spectrometry with anion exchange chromatographic separation.

    PubMed

    Chen, Xiaopan; Han, Chao; Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Yin, Xuefeng

    2013-09-24

    This work demonstrated the feasibility of mercury speciation analysis by anion exchange chromatographic separation with inductively coupled plasma mass spectrometry detection. For the first time, by complexing with the mobile phase containing 3-mercapto-1-propanesulfonate into negatively charged complexes, fast separation of inorganic mercury (Hg(2+)), monomethylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg) was achieved within 5 min on a 12.5-mm strong anion exchange column. The detection limits for Hg(2+), MeHg, EtHg and PhHg were 0.008, 0.024, 0.029 and 0.034 μg L(-1), respectively. The relative standard deviations of peak height and peak area (5.0 μg L(-1) for each Hg species) were all below 3%. The determined contents of Hg(2+), MeHg and total Hg in a certified reference material of fish tissue by the proposed method were in good accordance with the certified values with satisfactory recoveries. The relative errors for determining MeHg and total mercury were -2.4% and -1.2%, respectively, with an acceptable range for spike recoveries of 94-101%. Mercury speciation in 11 fish samples were then analyzed after the pretreated procedure. The mercury contents in all fish samples analyzed were found compliant with the criteria of the National Standards of China.

  9. A compact, low-cost, passive MMW security scanner

    NASA Astrophysics Data System (ADS)

    Williams, Thomas D.; Vaidya, Nitin M.

    2005-05-01

    We describe a low-cost passive millimeter wave (MMW) scanning camera for detecting concealed weapons and contraband. It is based on a focal plane array of 64 radiometric channels that employ MMICs operating at 94 GHz. Equipped with a 125 mm primary optic, the camera achieves a 26 26 degrees field of view by means of a rotating optic that performs 10 conical scans of the scene per second. The resulting 10 Hz rate images are of size 28 by 28, yielding a spatial resolution of 5 cm at a range of 1.6 meters from the camera. The radiometric sensitivity, at the maximum frame rate, is given by a median of under 3 Kelvin. With a size of 8 in. 8 in. 22 in. and a weight of 26 lbs., the camera is very compact and portable. This development may constitute the first affordable, commercially available passive MMW scanning camera. When operated at the slower frame rate of 1 Hz, the resulting time integration improves the image to less than 1 Kelvin, making the camera well suited for the detection of a wide variety of threats at security checkpoints. At finer camera sensitivity levels, the possibility arises of the exposure of anatomic details of the scanned subjects. In view of this, we have developed specialized display software that allows the presentation of the MMW scanning results in a manner that overcomes privacy concerns.

  10. Medial opening-wedge high tibial osteotomy fixation with short plate without any graft, synthetic material or spacer.

    PubMed

    Türkmen, Faik; Sever, Cem; Kacıra, Burkay K; Demirayak, Mehmet; Acar, Mehmet Ali; Toker, Serdar

    2014-12-01

    Medial opening-wedge high tibial osteotomy (MOWHTO) is an effective surgical procedure for patients who have medial compartmental osteoarthritis of the knee with varus deformity of the limb. The abnormal load on the medial compartment of the knee is directed to the lateral compartment with this procedure. A gap occurs on the proximal tibia while providing adequate correction. Filling this gap with bone grafts or synthetic materials has gained wide acceptance for preventing bone union problems or osteotomy site collapse. The aim of this study is to report our results of MOWHTOs performed without any bone graft or any other synthetic materials. We evaluated 41 MOWHTOs that have been performed between 2009 and 2012 with no use of any grafts or synthetic materials and spacer. Age of the patients ranged from 43 to 67. Thirty-five of the patients were females and three of them were males. The follow-up time was 6 months. Seven knees had opening at the osteotomy site <10 mm, 26 knees had 10-12.5 mm, and eight knees had >12.5 mm (range 7.5-14 mm, mean 11.07 mm). All osteotomies united without loss of correction. The mean bone union time was 12.8 weeks. We did not have any major complication regarding the technique. The results of our study have shown that we can achieve satisfactory and good results by performing MOWHTO procedure without using any bone grafts or synthetic materials and spacer.

  11. Adaptive Statistical Iterative Reconstruction-V Versus Adaptive Statistical Iterative Reconstruction: Impact on Dose Reduction and Image Quality in Body Computed Tomography.

    PubMed

    Gatti, Marco; Marchisio, Filippo; Fronda, Marco; Rampado, Osvaldo; Faletti, Riccardo; Bergamasco, Laura; Ropolo, Roberto; Fonio, Paolo

    2017-09-20

    The aim of this study was to evaluate the impact on dose reduction and image quality of the new iterative reconstruction technique: adaptive statistical iterative reconstruction (ASIR-V). Fifty consecutive oncologic patients acted as case controls undergoing during their follow-up a computed tomography scan both with ASIR and ASIR-V. Each study was analyzed in a double-blinded fashion by 2 radiologists. Both quantitative and qualitative analyses of image quality were conducted. Computed tomography scanner radiation output was 38% (29%-45%) lower (P < 0.0001) for the ASIR-V examinations than for the ASIR ones. The quantitative image noise was significantly lower (P < 0.0001) for ASIR-V. Adaptive statistical iterative reconstruction-V had a higher performance for the subjective image noise (P = 0.01 for 5 mm and P = 0.009 for 1.25 mm), the other parameters (image sharpness, diagnostic acceptability, and overall image quality) being similar (P > 0.05). Adaptive statistical iterative reconstruction-V is a new iterative reconstruction technique that has the potential to provide image quality equal to or greater than ASIR, with a dose reduction around 40%.

  12. The effect of chemical agents on the turnover of the bound phosphate associated with the sodium-and-potassium ion-stimulated adenosine triphosphatase in ox brain microsomes

    PubMed Central

    Rodnight, R.

    1970-01-01

    1. The effect of chemical agents on the turnover of the Na+-dependent bound phosphate and the simultaneous Na+-dependent hydrolysis of ATP by a membrane preparation from ox brain was studied at an ATP/protein ratio of 12.5pmol/μg. 2. The agents were added immediately after phosphorylation of the preparation in a medium containing 50mm-sodium chloride and 2.5μm-[γ-32P]ATP. 3. Concentrations of sodium chloride above 150mm, calcium chloride to 20mm and suramin to 1.4mm inhibited both phosphorylation and dephosphorylation and concomitantly slowed ATP hydrolysis. At 125mm-sodium chloride dephosphorylation and hydrolysis were slightly slowed without affecting phosphorylation. 4. Ethanol to 1.6m concentration inhibited dephosphorylation without affecting phosphorylation; the bound phosphate was increased and ATP hydrolysis slowed. 5. Ouabain to 4mm concentration partially inhibited ATP hydrolysis and caused a transient (1–2s) rise in bound phosphate followed by a rapid fall to a lower plateau value, which eventually declined to zero by the time ATP hydrolysis was complete. 6. Of the detergents examined Lubrol W, Triton X-100 and sodium deoxycholate had no significant effect on turnover. Sodium dodecyl sulphate and sodium decyl sulphate to 3.5mm and 20mm respectively completely inhibited turnover and ATP hydrolysis and stabilized the bound phosphate. PMID:4250238

  13. Efficient second-harmonic generation of a diode-laser-pumped c-w Nd:YAG laser using monolithic MGo:LiNbO sub 3 external resonant cavities

    SciTech Connect

    Byer, R.L.; Nabors, C.D.; Kozlovsky, W.J.

    1988-06-01

    The authors report 56% efficient external-cavity-resonant second-harmonic generation of a diode-laser pumped, C-W single-axial-mode Nd:YAG laser. A theory of external doubling with a resonant fundamental is presented and compared to experimental results for three monolithic cavities of nonlinear MgO: LiNbO{sub 3}. The best conversion efficiency was obtained with a 12.5-mm long monolithic ring cavity doubler, which produced 29.7 MW of C-W, single axial mode 532-nm radiation from an input of 52.6 mW. There has been increasing interest in the development and applications of diode-laser-pumped solid-state lasers. Diode-laser-pumped lasers offer improved reliability, efficiency, and frequency stability compared to lamp-pumped lasers. An important application of diode-laser-pumped solid-state lasers is in the generation of visible radiation by frequency doubling 2.

  14. Attenuated total internal reflection infrared microspectroscopic imaging using a large-radius germanium internal reflection element and a linear array detector.

    PubMed

    Patterson, Brian M; Havrilla, George J

    2006-11-01

    The number of techniques and instruments available for Fourier transform infrared (FT-IR) microspectroscopic imaging has grown significantly over the past few years. Attenuated total internal reflectance (ATR) FT-IR microspectroscopy reduces sample preparation time and has simplified the analysis of many difficult samples. FT-IR imaging has become a powerful analytical tool using either a focal plane array or a linear array detector, especially when coupled with a chemometric analysis package. The field of view of the ATR-IR microspectroscopic imaging area can be greatly increased from 300 x 300 microm to 2500 x 2500 microm using a larger internal reflection element of 12.5 mm radius instead of the typical 1.5 mm radius. This gives an area increase of 70x before aberrant effects become too great. Parameters evaluated include the change in penetration depth as a function of beam displacement, measurements of the active area, magnification factor, and change in spatial resolution over the imaging area. Drawbacks such as large file size will also be discussed. This technique has been successfully applied to the FT-IR imaging of polydimethylsiloxane foam cross-sections, latent human fingerprints, and a model inorganic mixture, which demonstrates the usefulness of the method for pharmaceuticals.

  15. Recycling of construction and demolition waste materials: a chemical-mineralogical appraisal.

    PubMed

    Bianchini, G; Marrocchino, E; Tassinari, R; Vaccaro, C

    2005-01-01

    Building activity is currently demanding remarkable amounts of inert materials (such as gravel and sand) that are usually provided by alluvial sediments. The EU directives and Italian Legislation are encouraging the re-use of construction and demolition waste provided by continuous urban redevelopment. The re-utilisation of building waste is a relatively new issue for Italy: unfortunately the employment of recycled inert materials is still limited to general bulk and drainage fills, while a more complete re-evaluation is generally hampered by the lack of suitable recycling plants. In this paper, chemical-mineralogical characterization of recycled inert materials was carried out after preliminary crushing and grain-size sorting. XRF and XRD analysis of the different grain-size classes allowed us to recognise particular granulometric classes that can be re-utilised as first-order material in the building activity. Specifically, the presented chemical-mineralogical appraisal indicates that the recycled grain-size fraction 0.6-0.125 mm could be directly re-employed in the preparation of new mortar and concrete, while finer fractions could be considered as components for industrial processing in the preparation of cements and bricks/tiles.

  16. Residual strength assessment of low velocity impact damage of graphite-epoxy laminates

    NASA Technical Reports Server (NTRS)

    Lal, K. M.

    1983-01-01

    This report contains the study of Low Velocity Transverse Impact Damage of graphite-epoxy T300/5208 composite laminates. The specimen, 100 mm diameter clamped plates, were impact damaged by a cantilever-type instrumented 1-inch diameter steel ball. Study was limited to impact velocity 6 m/sec. Rectangular strips, 50 mm x 125 mm, were cut from the impact-damage specimens so that the impact damage zone was in the center of the strips. These strips were tested in tension to obtain their residual strength. An energy dissipation model was developed to predict the residual strength from fracture mechanics concepts. Net energy absorbed I(a) was evaluated from coefficient of restitution concepts based on shear dominated theory of fiber-reinforced materials, with the modification that during loading and unloading the shear deformation are respectively elastic-plastic and elastic. Delamination energy I(d) was predicted by assuming that the stiffness of the laminate dropped due to debonding. Fiber-breakage energy, assumed to be equal to the difference of I(a) and I(d), was used to determine the residual strength. Predictions were compared with test results.

  17. Wide-band, high-resolution soft x-ray spectrometer for the Electron Beam Ion Trap

    SciTech Connect

    Brown, G.V.; Beiersdorfer, P.; Widmann, K.

    1999-01-01

    We have constructed two wide-band, high-resolution vacuum flat crystal spectrometers and implemented them on the Electron Beam Ion Trap located at the Lawrence Livermore National Laboratory. Working in unison, these spectrometers can measure an x-ray bandwidth {le}9 {Angstrom} in the soft x-ray region below 21 {Angstrom}. In order to achieve this large bandwidth each spectrometer houses either two 125 mm {times} 13 mm {times} 2 mm RAP (rubidium acid phthalate, 2d=26.121 {Angstrom}), two 114 mm {times} 13 mm {times} 2 mm TlAP (thallium acid phthalate, 2d=25.75 {Angstrom}) crystals, or some combination thereof, for dispersion and two position sensitive proportional counters for detection of x rays. The spectrometers are used to measure wavelengths and relative intensities of the L-shell line emission from FethinspXVII{endash}XXIV for comparison with spectra obtained from astrophysical and laboratory plasmas. The wide wavelength coverage attainable by these spectrometers makes it possible to measure all the L-shell emission from a given iron ion species simultaneously. {copyright} {ital 1999 American Institute of Physics.}

  18. Comparison of media formulations used to selectively cultivate Dekkera/Brettanomyces.

    PubMed

    Morneau, A D; Zuehlke, J M; Edwards, C G

    2011-10-01

    The objectives of this research were to (i) optimize the concentration of cycloheximide for use in WL media used in the wine industry and (ii) evaluate Dekkera/Brettanomyces differential medium (DBDM) as a means to detect Dekkera. Dekkera bruxellensis and other yeasts were transferred into WL broths containing 0, 10, 50 or 100 mg l(-1) of cycloheximide. While several grew in 10 mg l(-1) , only Hanseniaspora uvarum, Pichia guillermondii, Schizosaccharomyces pombe and D. bruxellensis tolerated ≥50 mg l(-1) of the antibiotic. On solidified WL media after 8-days incubation, colony sizes of two strains of D. bruxellensis (B1b and ATCC 52905) decreased with increased concentrations of cycloheximide, while others (F3 and P2) were unaffected. Although D. bruxellensis B1b did not grow well on another selective medium, DBDM, colony development was improved by the addition of sterilized red wine. Of the concentrations tested, 50 mg l(-1) cycloheximide inhibited many grape/wine yeasts yet generally yielded countable colonies of Dekkera (1-2.5 mm diameter). Several strains of Dekkera did not grow well on DBDM, probably due to the lack of an unidentified nutrient(s). Better media formulations will improve the detection of Dekkera, thereby increasing microbiological control during winemaking. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  19. Linear Dimensional Stability of Irreversible Hydrocolloid Materials Over Time.

    PubMed

    Garrofé, Analía B; Ferrari, Beatriz A; Picca, Mariana; Kaplan, Andrea E

    2015-12-01

    The aim of this study was to evaluate the linear dimensional stability of different irreversible hydrocolloid materials over time. A metal mold was designed with custom trays made of thermoplastic sheets (Sabilex, sheets 0.125 mm thick). Perforations were made in order to improve retention of the material. Five impressions were taken with each of the following: Kromopan 100 (LASCOD) [AlKr], which has dimensional stability of 100 hours, and Phase Plus (ZHERMACK) [AlPh], which has dimensional stability of 48 hours. Standardized digital photographs were taken at different time intervals (0, 15, 30, 45, 60, 120 minutes; 12, 24 and 96 hours), using an "ad-hoc" device. The images were analyzed with software (UTHSCSA Image Tool) by measuring the distance between intersection of the lines previously made at the top of the mold. The results were analyzed by ANOVA for repeated measures. Initial and final values were (mean and standard deviation): AlKr: 16.44 (0.22) and 16.34 (0.11), AlPh: 16.40 (0.06) and 16.18 (0.06). Statistical evaluation showed significant effect of material and time factors. Under the conditions in this study, time significantly affects the linear dimensional stability of irreversible hydrocolloid materials.

  20. Two-Step Filament Eruption During 14 - 15 March 2015

    NASA Astrophysics Data System (ADS)

    Chandra, R.; Filippov, B.; Joshi, R.; Schmieder, B.

    2017-06-01

    We present here an interesting two-step filament eruption during 14 - 15 March 2015. The filament was located in NOAA AR 12297 and associated with a halo Coronal Mass Ejection (CME). We use observations from the Atmospheric Imaging Assembly (AIA) and Heliospheric Magnetic Imager (HMI) instruments onboard the Solar Dynamics Observatory (SDO), and from the Solar and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph (LASCO). We also use Hα data from the Global Oscillation Network Group (GONG) telescope and the Kanzelhoehe Solar Observatory. The filament shows a first step eruption on 14 March 2015 and it stops its rise at a projected altitude {≈} 125 Mm on the solar disk. It remains at this height for {≈} 12 hrs. Finally it erupts on 15 March 2015 and produces a halo CME. We also find jet activity in the active region during both days, which could help the filament de-stabilization and eruption. The decay index is calculated to understand this two-step eruption. The eruption could be due to the presence of successive instability-stability-instability zones as the filament is rising.

  1. A converging route towards very high frequency, mechanically flexible, and performance stable integrated electronics

    NASA Astrophysics Data System (ADS)

    Lecavelier des Etangs-Levallois, Aurélien; Chen, Zhenkun; Lesecq, Marie; Lepilliet, Sylvie; Tagro, Yoann; Danneville, François; Robillard, Jean-François; Hoel, Virginie; Troadec, David; Gloria, Daniel; Raynaud, Christine; Ratajczak, Jacek; Dubois, Emmanuel

    2013-04-01

    The ability to realize flexible circuits integrating sensing, signal processing, and communicating capabilities is of central importance for the development of numerous nomadic applications requiring foldable, stretchable, and large area electronics. A key challenge is, however, to combine high electrical performance (i.e., millimeter wave, low noise electronics) with mechanical flexibility required for chip form adaptivity in addition to highly stable electrical performance upon deformation. Here, we describe a solution based on ultimate thinning and transfer onto a plastic foil of high frequency CMOS devices initially processed on conventional silicon-on-insulator wafers. We demonstrate a methodology relying on neutral plane engineering to provide high performance stability upon bending, by locating the active layer, i.e., the transistor channel, at the neutral fiber of the flexible system. Following this strategy, record frequency performance of flexible n-MOSFETs, featuring fT/fMAX of 120/145 GHz, is reported with relative variations limited to less than 5% even under aggressive bending on cylinders with curvature radii down to 12.5 mm.

  2. Observing the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA): High-Resolution Interferometric Imaging

    NASA Astrophysics Data System (ADS)

    Shimojo, M.; Bastian, T. S.; Hales, A. S.; White, S. M.; Iwai, K.; Hills, R. E.; Hirota, A.; Phillips, N. M.; Sawada, T.; Yagoubov, P.; Siringo, G.; Asayama, S.; Sugimoto, M.; Brajša, R.; Skokić, I.; Bárta, M.; Kim, S.; de Gregorio-Monsalvo, I.; Corder, S. A.; Hudson, H. S.; Wedemeyer, S.; Gary, D. E.; De Pontieu, B.; Loukitcheva, M.; Fleishman, G. D.; Chen, B.; Kobelski, A.; Yan, Y.

    2017-07-01

    Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; the formation and eruption of prominences and filaments; and energetic phenomena such as jets and flares. High-resolution observations of the Sun at millimeter and submillimeter wavelengths are challenging due to the intense, extended, low-contrast, and dynamic nature of emission from the quiet Sun, and the extremely intense and variable nature of emissions associated with energetic phenomena. The Atacama Large Millimeter/submillimeter Array (ALMA) was designed with solar observations in mind. The requirements for solar observations are significantly different from observations of sidereal sources and special measures are necessary to successfully carry out this type of observations. We describe the commissioning efforts that enable the use of two frequency bands, the 3-mm band (Band 3) and the 1.25-mm band (Band 6), for continuum interferometric-imaging observations of the Sun with ALMA. Examples of high-resolution synthesized images obtained using the newly commissioned modes during the solar-commissioning campaign held in December 2015 are presented. Although only 30 of the eventual 66 ALMA antennas were used for the campaign, the solar images synthesized from the ALMA commissioning data reveal new features of the solar atmosphere that demonstrate the potential power of ALMA solar observations. The ongoing expansion of ALMA and solar-commissioning efforts will continue to enable new and unique solar observing capabilities.

  3. Sound propagation through internal gravity wave fields in a laboratory tank

    NASA Astrophysics Data System (ADS)

    Zhang, Likun; Swinney, Harry L.; Lin, Ying-Tsing

    2014-11-01

    We conduct laboratory experiments and numerical simulations for sound propagation through an internal gravity wave field. The goal is to improve the understanding of the effect of internal gravity waves on acoustic propagation in the oceans. The laboratory tank is filled with a fluid whose density decreases linearly from the bottom to the top of the tank; the resultant buoyancy frequency is 0.15 Hz. A 1 MHz sound wave is generated and received by 12.5 mm diameter transducers, which are positioned 0.2 m apart on a horizontal acoustic axis that is perpendicular to the internal wave beam. The fluid velocity field, measured by Particle Image Velocimetry (PIV), agrees well with results from simulations made using a Navier-Stokes spectral code. The sound intensity at the receiver is computed numerically for different measured and simulated frozen density fields. Fluctuations in the sound speed and intensity are determined as a function of the location of the receiver and the frequency and phase of the internal waves. Supported by ONR MURI Grant N000141110701 (WHOI). Also, L.Z. is supported by the 2013-14 ASA F. V. Hunt Postdoctoral Research Fellowship.

  4. Modeling bipolar phase-shifted multielectrode catheter ablation.

    PubMed

    Tungjitkusolmun, Supan; Haemmerich, Dieter; Cao, Hong; Tsai, Jang-zern; Choy, Young Bin; Vorperian, Vicken R; Webster, John G

    2002-01-01

    Atrial fibrillation (AFIB) is a common clinical problem affecting approximately 0.5-1% of the United States population. Radio-frequency (RF) multielectrode catheter (MEC) ablation has successes in curing AFIB. We utilized finite-element method analysis to determine the myocardial temperature distribution after 30 s, 80 degrees C temperature-controlled unipolar ablation using three 7F 12.5-mm electrodes with 2-mm interelectrode spacing MEC. Numerical results demonstrated that cold spots occurred at the edges of the middle electrode and hot spots at the side electrodes. We introduced the bipolar phase-shifted technique for RF energy delivery of MEC ablation. We determined the optimal phase-shift (phi) between the two sinusoidal voltage sources of a simplified two-dimensional finite-element model. At the optimal phi, we can achieve a temperature distribution that minimizes the difference between temperatures at electrode edges. We also studied the effects of myocardial electric conductivity (sigma), thermal conductivity (k), and the electrode spacing on the optimal phi. When we varied sigma and kappa from 50% to 150%, optimal phi ranged from 29.5 degrees to 23.5 degrees, and in the vicinity of 26.5 degrees, respectively. The optimal phi for 3-mm spacing MEC was 30.5 degrees. We show the design of a simplified bipolar phase-shifted MEC ablation system.

  5. Two-phase flow patterns characteristics analysis based on image and conductance sensors

    NASA Astrophysics Data System (ADS)

    Wang, Zhenya; Jin, Ningde; Wang, Chun; Wang, Jinxiang

    2008-10-01

    In order to study the temporal and spatial evolution characteristics of gas-liquid two-phase flow pattern, the two-phase flow monitoring system composed of high-speed dynamic camera and Vertical Multi-Electrode Array conductance sensor (VMEA) was utilized to shoot dynamic images and acquire the conductance fluctuating signals of 5 typical vertical gas-liquid two-phase flow patterns in a 125mm i.d. upward pipe. Gray level co-occurrence matrix (GLCM) was used to extract four time-varying characteristic parameter indices which represented different flow image texture structures and also Lempel-Ziv complexity of them were calculated. Then the transition of flow structure and flow property were comprehensively analyzed, combining the result derived from image information with recurrence plots (RPs) and Lempel-Ziv complexity of conductance fluctuating signals. The study showed that the line texture structure of RPs enabled to indicate flow pattern characteristics; the flow image texture structure characteristic parameters sequence described the variance of flow structure and dynamical complexity of different flow patterns.

  6. Spacing in deciduous dentition of Polish children in relation to tooth size and dental arch dimensions.

    PubMed

    Janiszewska-Olszowska, Joanna; Stepien, Piotr; Syrynska, Maria

    2009-05-01

    To assess the prevalence of primary and secondary spacing in the deciduous dentition and its correlation to tooth widths and dental arch dimensions. Dental casts of 50 preschool children free from malocclusion, were analysed. The width of each space was measured as the smallest distance between the proximal surfaces of the neighbouring teeth, parallel to the occlusal plane. Crown width was measured as the greatest distance between the mesial and distal surfaces of the crown, parallel to the occlusal plane. Intercanine widths were measured between cusp tips of upper and lower canines. Intermolar widths were measured between the central fossae of the second molars. Arch lengths were measured from the midpoint between the central incisors to the midpoint between the distal surfaces of the deciduous second molars. The primary spaces were present in the upper dental arch in 90% children, on the average 2.09 mm in maxilla and 1.25 mm in mandible. Their widths were dependent on upper intercanine width. Secondary spacing was present in 92% children in the upper dental arch (mean 2.86 mm) and 90% in the lower (mean 3.08 mm). Lower secondary spacing was correlated to lower intercanine width and lower arch length. Total absence of interdental spacing was found in 4% children. Interdental spacing of the deciduous dentition is present in 96% of Polish children. Children with wider intercanine widths have wider primary spaces in maxilla and wider secondary spaces in mandible.

  7. Peri-implant bone loss of dental implants with platform-switching design after 5 years of loading: a cross-sectional study.

    PubMed

    Joda, Tim; Michelaki, Ioanna; Heydecke, Guido

    2015-01-01

    The aim of this cross-sectional study was to estimate bone loss of implants with platform-switching design and analyze possible risk indicators after 5 years of loading in a multi-centered private practice network. Peri-implant bone loss was measured radiographically as the distance from the implant shoulder to the mesial and distal alveolar crest, respectively. Risk factor analysis for marginal bone loss included type of implant prosthetic treatment concept and dental status of the opposite arch. A total of 316 implants in 98 study patients after 5 years of loading were examined. The overall mean value for radiographic bone loss was 1.02 mm (SD ± 1.25 mm, 95% CI 0.90- 1.14). Correlation analyses indicated a strong association of peri-implant bone loss > 2 mm for removable implant-retained prostheses with an odds ratio of 53.8. The 5-year-results of the study show clinically acceptable values of mean bone loss after 5 years of loading. Implant-supported removable prostheses seem to be a strong co-factor for extensive bone level changes compared to fixed reconstructions. However, these results have to be considered for evaluation of the included special cohort under private dental office conditions.

  8. Femtosecond Laser-Assisted Tuck-In Penetrating Keratoplasty for Advanced Keratoglobus With Endothelial Damage.

    PubMed

    Alió Del Barrio, Jorge L; Al-Shymali, Olena; Alió, Jorge L

    2017-09-01

    To describe the outcomes of femtosecond laser-assisted tuck-in penetrating keratoplasty as a single-step surgical procedure for visual and anatomical rehabilitation of patients with severe keratoglobus (KTG) and endothelial damage. Two eyes of a 7-year-old patient with bilateral severe KTG and previous corneal hydrops were operated. Assisted by the femtosecond laser, both donor and recipient corneas were prepared. An 8.5-mm full-thickness donor tissue with a peripheral partial-thickness rim of 1.25 mm was sutured into an 8.5-mm recipient bed with a previously dissected intralamellar peripheral pocket up to the limbus. The graft was secured with 16 interrupted 10-0 nylon sutures and the peripheral donor rim tucked into the host stromal pocket. Six months after surgery, both grafts remained healthy and clear. One eye developed mild postoperative ocular hypertension. No intraoperative or other postoperative complications were observed. Corrected distance visual acuity was 20/50 in both eyes, with complete functional rehabilitation of the patient. Restoration of the peripheral corneal thickness was observed in the pachymetric map. Femtosecond laser-assisted tuck-in penetrating keratoplasty can provide excellent anatomical and functional rehabilitation of patients with severe KTG and endothelial damage, through a single-step surgical procedure and a single donor cornea per eye. The femtosecond laser permits accurate dissection of these already thin corneas without inadvertent perforation risk.

  9. Development of a Compact Rectenna for Wireless Powering of a Head-Mountable Deep Brain Stimulation Device.

    PubMed

    Hosain, M D Kamal; Kouzani, Abbas Z; Tye, Susannah J; Abulseoud, Osama A; Amiet, Andrew; Galehdar, Amir; Kaynak, Akif; Berk, Michael

    2014-01-01

    Design of a rectangular spiral planar inverted-F antenna (PIFA) at 915 MHz for wireless power transmission applications is proposed. The antenna and rectifying circuitry form a rectenna, which can produce dc power from a distant radio frequency energy transmitter. The generated dc power is used to operate a low-power deep brain stimulation pulse generator. The proposed antenna has the dimensions of 10 mm [Formula: see text]12.5 mm [Formula: see text]1.5 mm and resonance frequency of 915 MHz with a measured bandwidth of 15 MHz at return loss of [Formula: see text]. A dielectric substrate of FR-4 of [Formula: see text] and [Formula: see text] with thickness of 1.5 mm is used for both antenna and rectifier circuit simulation and fabrication because of its availability and low cost. An L-section impedance matching circuit is used between the PIFA and voltage doubler rectifier. The impedance matching circuit also works as a low-pass filter for elimination of higher order harmonics. Maximum dc voltage at the rectenna output is 7.5 V in free space and this rectenna can drive a deep brain stimulation pulse generator at a distance of 30 cm from a radio frequency energy transmitter, which transmits power of 26.77 dBm.

  10. Studies into Using Manure in a Biorefinery Concept

    SciTech Connect

    Chen, Shulin; Wen, Zhiyou; Liao, Wei; Liu, Chuanbin; Kincaid, R. L.; Harrison, J. H.; Elliott, Douglas C.; Brown, Michael D.; Stevens, Don J.

    2005-03-01

    Animal manure is an underutilized biomass resource containing a large amount of organic carbon that is often wasted in the existing manure disposal practices. A research project funded by the US Department of Energy explored the feasibility of using manure via the sugar platform in a biorefinery. The results showed that fiber, the major component of dry manure, constituted approximately 50%, 40%, and 36% of the dry dairy, swine, and poultry manure materials, respectively. The highest fiber contents were in dairy manure of which more than 75% of the dry matter was in the particles greater than 0.125 mm. Manure can be used for substrate to produce cellulase on site. The hemicellulose component in the manure fiber could be readily converted to sugar through acid hydrolysis. Concentrated acid treatment was most effective in manure cellulose decrystallization. The effectiveness of enzymatic hydrolysis was limited without concentrated acid pretreatment. The high protein content in manure had negative affects on acid hydrolysis. Purification and separation is necessary for further chemical conversion of the sugar to value-added chemicals through hydrogenation.

  11. Novel 16-channel receive coil array for accelerated upper airway MRI at 3 Tesla.

    PubMed

    Kim, Yoon-Chul; Hayes, Cecil E; Narayanan, Shrikanth S; Nayak, Krishna S

    2011-06-01

    Upper airway MRI can provide a noninvasive assessment of speech and swallowing disorders and sleep apnea. Recent work has demonstrated the value of high-resolution three-dimensional imaging and dynamic two-dimensional imaging and the importance of further improvements in spatio-temporal resolution. The purpose of the study was to describe a novel 16-channel 3 Tesla receive coil that is highly sensitive to the human upper airway and investigate the performance of accelerated upper airway MRI with the coil. In three-dimensional imaging of the upper airway during static posture, 6-fold acceleration is demonstrated using parallel imaging, potentially leading to capturing a whole three-dimensional vocal tract with 1.25 mm isotropic resolution within 9 sec of sustained sound production. Midsagittal spiral parallel imaging of vocal tract dynamics during natural speech production is demonstrated with 2 × 2 mm(2) in-plane spatial and 84 ms temporal resolution. Copyright © 2010 Wiley-Liss, Inc.

  12. Large-area low-noise seven-channel dc SQUID magnetometer for brain research

    SciTech Connect

    Knuutila, J.; Ahlfors, S.; Ahonen, A.; Haellstroem, J.; Kajola, M.; Lounasmaa, O.V.; Vilkman, V.; Tesche, C.

    1987-11-01

    The design, construction, and performance of a new high-sensitivity dc SQUID magnetometer, covering a circular area of 93-mm diameter, is described. The device, now used routinely in our brain research, comprises seven asymmetric first-order gradiometers, located on a spherical surface of 125-mm radius and with the symmetry axis tilted 30/sup 0/ with respect to the vertical. The pickup coil diameter is 20 mm, and the channels are separated by 36.5 mm from each other in a hexagonal array. The overall field sensitivity of the system, measured inside our magnetically shielded room, is 5 fT/(Hz)/sup 1/2/, mainly limited by the thermal noise in the radiation shields of the Dewar. The optimization of the coil configuration and the measurement system is discussed in detail, and a system to determine automatically the position and orientation of the Dewar with respect to certain fixed points on the subject's head is described. Finally, some examples of measurements carried out with the new device are given.

  13. Role of indenter material and size in veneer failure of brittle layer structures.

    PubMed

    Bhowmick, Sanjit; Meléndez-Martínez, Juan José; Hermann, Ilja; Zhang, Yu; Lawn, Brian R

    2007-07-01

    The roles of indenter material and size in the failure of brittle veneer layers in all-ceramic crown-like structures are studied. Glass veneer layers 1 mm thick bonded to alumina layers 0.5 mm thick on polycarbonate bases (representative of porcelain/ceramic-core/dentin) are subject to cyclic contact loading with spherical indenters in water (representative of occlusal biting environment). Two indenter materials-glass and tungsten carbide-and three indenter radii-1.6, 5.0, and 12.5 mm-are investigated in the tests. A video camera is used to follow the near-contact initiation and subsequent downward propagation of cone cracks through the veneer layer to the core interface, at which point the specimen is considered to have failed. Both indenter material and indenter radius have some effect on the critical loads to initiate cracks within the local Hertzian contact field, but the influence of modulus is weaker. The critical loads to take the veneer to failure are relatively insensitive to either of these indenter variables, since the bulk of the cone crack propagation takes place in the contact far field. Clinical implications of the results are considered, including the issue of single-cycle overload versus low-load cyclic fatigue and changes in fracture mode with loading conditions.

  14. Effect of Different Coarse Aggregate Sizes on the Strength Characteristics of Laterized Concrete

    NASA Astrophysics Data System (ADS)

    Salau, M. A.; Busari, A. O.

    2015-11-01

    The high cost of conventional concrete materials is a major factor affecting housing delivery in developing countries such as Nigeria. Since Nigeria is blessed with abundant locally available materials like laterite, researchers have conducted comprehensive studies on the use of laterite to replace river sand partially or fully in the concrete. However, the works did not consider the optimum use of coarse aggregate to possibly improve the strength of the laterized concrete, since it is normally lower than that of normal concrete. The results of the tests showed that workability, density and compressive strength at constant water-cement ratio increase with the increase in the coarse aggregate particle size and also with curing age. As the percentage of laterite increases, there was a reduction in all these characteristics even with the particle size of coarse aggregate reduction due to loss from the aggregate-paste interface zone. Also, when sand was replaced by 25% of laterite, the 19.5mm and 12.5mm coarse aggregate particle sizes gave satisfactory results in terms of workability and compressive strength respectively at 28 days of curing age, compared to normal concrete. However, in case of 50% up to 100% laterite contents, the workability and compressive strength values were very low.

  15. [Clinical and radiological follow-up of Nubac disc prosthesis. Preliminary report].

    PubMed

    Alpízar-Aguirre, Armando; Mireles-Cano, José Nicolás; Rosales-Olivares, Miguel; Miramontes-Martínez, Víctor; Reyes-Sánchez, Alejandro

    2008-01-01

    Lumbar arthroplasty is an alternative to fusion for the treatment of degenerative disc disease. Replacement of the nucleus pulposus preserves the biomechanical properties in the annulus and plates, conserving lumbar motion. Our objective was to evaluate the feasibility and clinical and radiological findings at 3 months follow-up with the Nubac device. Ten patients from the National Institute for Rehabilitation (INR, Mexico City) with degenerative disc disease were selected to participate in the study. They underwent discectomy with Nubac device with a follow-up period of 3 months. Evolution was evaluated with the VAS and Oswestry scales. Five men and five women were included in the study (average age 41.6 years). Surgical approach was anterolateral (4 patients), posterior (3 patients) and anterior (3 patients), VAS improved from 8.1 to 2.5 (p <0.05) and Oswestry Disability Index (ODI) improved from 58.2% to 24.2% (p <0.05). Disc height before surgery was 9.4 mm, and 3 months postoperatively was 12.5 mm with no complications, migration, or subsidence. Nubac prosthesis improved lumbar discogenic pain in a short time when evaluated using ODI and VAS scales. Disc height improved after a 3-month follow-up, but lumbar motion did not improve. No complications have been reported; however, a minimum follow-up of 4 years is needed to make a definite conclusion.

  16. The spectrum and variability of radio emission from AE Aquarii

    NASA Technical Reports Server (NTRS)

    Abada-Simon, Meil; Lecacheux, Alain; Bastian, Tim S.; Bookbinder, Jay A.; Dulk, George A.

    1993-01-01

    The first detections of the magnetic cataclysmic variable AE Aquarii at millimeter wavelengths are reported. AE Aqr was detected at wavelengths of 3.4 and 1.25 mm. These data are used to show that the time-averaged spectrum is generally well fitted by a power law S(nu) varies as nu exp alpha, where alpha is approximately equal to 0.35-0.60, and that the power law extends to millimeter wavelengths, i.e., the spectral turnover is at a frequency higher than 240 GHz. It is suggested that the spectrum is consistent with that expected from a superposition of flarelike events where the frequency distribution of the initial flux density is a power law f (S0) varies as S0 exp -epsilon, with index epsilon approximately equal to 1.8. Within the context of this model, the high turnover frequency of the radio spectrum implies magnetic field strengths in excess of 250 G in the source.

  17. Optical properties of neonatal skin measured in vivo as a function of age and skin pigmentation.

    PubMed

    Bosschaart, Nienke; Mentink, Rosaline; Kok, Joke H; van Leeuwen, Ton G; Aalders, Maurice C G

    2011-09-01

    Knowledge of the optical properties of neonatal skin is invaluable when developing new, or improving existing optical techniques for use at the neonatal intensive care. In this article, we present in vivo measurements of the absorption μ(a) and reduced scattering coefficient μ(s) (') of neonatal skin between 450 and 600 nm and assess the influence of age and skin pigmentation on the optical properties. The optical properties were measured using a spatially resolved, steady state diffuse reflectance spectroscopy setup, combined with a modified spatially resolved diffusion model. The method was validated on phantoms with known values for the absorption and reduced scattering coefficient. Values of μ(a) and μ(s) (') were obtained from the skin at four different body locations (forehead, sternum, hand, and foot) of 60 neonates with varying gestational age, postnatal age, and skin pigmentation. We found that μ(a) ranged from 0.02 to 1.25 mm(-1) and μ(s) (') was in the range of 1 to 2.8 mm(-1) (5th to 95th percentile of the patient population), independent of body location. In contrast to previous studies, no to very weak correlation was observed between the optical properties and gestational maturity, but a strong dependency of the absorption coefficient on postnatal age was found for dark skinned patients.

  18. Functional Characterization of Ice Plant SKD1, an AAA-Type ATPase Associated with the Endoplasmic Reticulum-Golgi Network, and Its Role in Adaptation to Salt Stress1[W

    PubMed Central

    Jou, Yingtzy; Chiang, Chih-Pin; Jauh, Guang-Yuh; Yen, Hungchen Emilie

    2006-01-01

    A salt-induced gene mcSKD1 (suppressor of K+ transport growth defect) able to facilitate K+ uptake has previously been identified from the halophyte ice plant (Mesembryanthemum crystallinum). The sequence of mcSKD1 is homologous to vacuolar protein sorting 4, an ATPase associated with a variety of cellular activities-type ATPase that participates in the sorting of vacuolar proteins into multivesicular bodies in yeast (Saccharomyces cerevisiae). Recombinant mcSKD1 exhibited ATP hydrolytic activities in vitro with a half-maximal rate at an ATP concentration of 1.25 mm. Point mutations on active site residues abolished its ATPase activity. ADP is both a product and a strong inhibitor of the reaction. ADP-binding form of mcSDK1 greatly reduced its catalytic activity. The mcSKD1 protein accumulated ubiquitously in both vegetative and reproductive parts of plants. Highest accumulation was observed in cells actively engaging in the secretory processes, such as bladder cells of leaf epidermis. Membrane fractionation and double-labeling immunofluorescence showed the predominant localization of mcSKD1 in the endoplasmic reticulum-Golgi network. Immunoelectron microscopy identified the formation of mcSKD1 proteins into small aggregates in the cytosol and associated with membrane continuum within the endomembrane compartments. These results indicated that this ATPase participates in the endoplasmic reticulum-Golgi mediated protein sorting machinery for both housekeeping function and compartmentalization of excess Na+ under high salinity. PMID:16581876

  19. Stability of [6]-gingerol and [6]-shogaol in simulated gastric and intestinal fluids.

    PubMed

    Bhattarai, Sushila; Tran, Van H; Duke, Colin C

    2007-11-30

    The degradation kinetics of [6]-gingerol and [6]-shogaol were investigated in simulated gastric (pH 1) and intestinal (pH 7.4) fluids at 37 degrees C. Degradation products were quantitatively determined by HPLC (Lichrospher 60 RP select B column, 5 microm, 125 mm x 4 mm; mobile phase: methanol-water-acetic acid (60:39:1 v/v); flow rate: 0.6 ml/min; detection UV: 280 nm). In simulated gastric fluid (SGF) [6]-gingerol and [6]-shogaol underwent first-order reversible dehydration and hydration reactions to form [6]-shogaol and [6]-gingerol, respectively. The degradation was catalyzed by hydrogen ions and reached equilibrium at approximately 200 h. In simulated intestinal fluid (SIF) both [6]-gingerol and [6]-shogaol showed insignificant interconversion between one another. Addition of amino acids glycine, 3-amino propionic acid (beta-alanine) and gamma-amino butyric acid (GABA), and ammonium acetate at a range of concentrations of 0.05-0.5mM had no effect on the rate of degradation of [6]-shogaol in SGF and 0.1M HCl solution. However, at exceedingly high concentration (0.5M) of ammonium acetate and glycine, significant amounts of [6]-shogaol ammonia and glycine adducts were detected. The degradation profile of [6]-gingerol and [6]-shogaol under simulated physiological conditions reported in this study will provide insight into the stability of these compounds when administered orally.

  20. Quantifying the transport of energetic materials in unsaturated sediments from cracked unexploded ordnance.

    PubMed

    Lewis, Jeffrey; Martel, Richard; Trépanier, Luc; Ampleman, Guy; Thiboutot, Sonia

    2009-01-01

    Dissolved explosive species have been found in the groundwater under military training areas. These explosives are thought to originate from munitions although the mechanism of transport to the groundwater is poorly understood. This study was conducted to determine whether ruptured unexploded ordnance may be a viable source term for these explosives. The rupturing effect of one 81 mm-mortar exploding in close proximity to another 81-mm mortar was observed and the resulting contaminants were collected. These contaminants were then subjected to leaching experiments on repacked, jack drill compacted unsaturated sediment columns in a climate controlled laboratory. The mortars which were exposed to nearby explosions were shown to be susceptible to rupturing rather than sympathetically detonating under certain conditions. The ruptured mortars released up to 166+/-2 g of pulverized explosive residues (largely Composition B) and the results from the subsequent leaching tests showed that this explosive residue is highly mobile in unsaturated sandy soil. Up to 4.45+/-1.00 g of dissolved explosive contamination was transported through the unsaturated soil columns during the first year of infiltration. The results indicate the mass of transported explosive residue dissolved in the leachate was primarily caused by the preferential dissolution of explosive contaminants having a grain size under 0.125 mm. Surface or near-surface unexploded ordnance (UXO) on live fire ranges may therefore be significant sources of explosive environmental contamination after they have been exposed to other rounds which explode nearby.

  1. Bead characterization of disk-laser butt welding of thin AA 2024 sheets

    NASA Astrophysics Data System (ADS)

    Caiazzo, Fabrizia; Alfieri, Vittorio; Cardaropoli, Francesco; Sergi, Vincenzo

    2012-03-01

    Higher productivity, lower distortion and better penetration are the main advantages which laser welding provides in comparison with conventional processes. A Trumpf TruDisk 2002 Yb:YAG disk-laser is used in this work, as it increases productivity and quality. Materials which involve many technological issues in welding, resulting in shallow penetration and defects, are aluminum alloys. In particular, AA 2024 behaviour is investigated in the paper, being this alloy extensively used in automotive and aerospace industries. Defocusing has been considered, as it affects key-holes conditions. Bead-on-plate and butt autogenous welding tests in continuous wave emission on 1.25 mm thick sheets have been examined from morphological and microstructural point of view. Geometric and mechanical features of the welding bead have been evaluated via a 3-levels experimental plan with power, welding speed and defocusing as governing factors. Softening in the fused zone through Vickers microhardness test and magnesium loss through energy dispersive spectrometer analysis have been discussed. Optimal welding conditions have been suggested.

  2. Silicone-coated non-woven polyester dressing enhances reepithelialisation in a sheep model of dermal wounds.

    PubMed

    Losi, Paola; Briganti, Enrica; Costa, Manolo; Sanguinetti, Elena; Soldani, Giorgio

    2012-09-01

    Negative-pressure wound therapy (NPWT) also known as V.A.C. (Vacuum-assisted closure), is widely used to manage various type of wounds and accelerate healing. NPWT has so far been delivered mainly via open-cell polyurethane (PU) foam or medical gauze. In this study an experimental setup of sheep wound model was used to evaluate, under NPWT conditions, the performance of a silicone-coated non-woven polyester (N-WPE) compared with PU foam and cotton hydrophilic gauze, used as reference materials. Animals were anesthetized with spontaneous breathing to create three 3 × 3 cm skin defects bilaterally; each animal received three different samples on each side (n = 6 in each experimental group) and was subjected to negative and continuous 125 mmHg pressure up to 16 days. Wound conditions after 1, 8 and 16 days of treatment with the wound dressings were evaluated based on gross and histological appearances. Skin defects treated with the silicone-coated N-WPE showed a significant decrease in wound size, an increase of re-epithelialization, collagen deposition and wound neovascularisation, and a minimal stickiness to the wound tissue, in comparison with gauze and PU foam. Taken all together these findings indicate that the silicone-coated N-WPE dressing enhances wound healing since stimulates higher granulation tissue formation and causes minor tissue trauma during dressing changes.

  3. Relationships between skin color, income, and blood pressure among African Americans in the CARDIA Study.

    PubMed

    Sweet, Elizabeth; McDade, Thomas W; Kiefe, Catarina I; Liu, Kiang

    2007-12-01

    We explored how income and skin color interact to influence the blood pressure of African American adults enrolled in the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) Study. Data were derived from 1893 African American CARDIA year-15 participants who had undergone skin reflectance assessments at year 7. We adjusted for age, gender, body mass index, smoking status, and use of antihypertensive medication to examine whether year-15 self-reported family incomes, in interaction with skin reflectance, predicted blood pressure levels. Mean systolic and diastolic blood pressure levels were 117.1 (+/-16.07) and 76.9 (+/-12.5) mm Hg, respectively. After adjustment, the interaction between skin reflectance and income was significantly associated with systolic blood pressure (P< .01). Among lighter-skinned African Americans, systolic pressure decreased as income increased (b= -1.15, P<.001); among those with darker skin, systolic blood pressure increased with increasing income (b=0.10, P=.75). The protective gradient of income on systolic blood pressure seen among African Americans with lighter skin is not observed to the same degree among those with darker skin. Psychosocial stressors, including racial discrimination, may play a role in this relationship.

  4. Silk: Optical Properties over 12.6 Octaves THz-IR-Visible-UV Range.

    PubMed

    Balčytis, Armandas; Ryu, Meguya; Wang, Xuewen; Novelli, Fabio; Seniutinas, Gediminas; Du, Shan; Wang, Xungai; Li, Jingliang; Davis, Jeffrey; Appadoo, Dominique; Morikawa, Junko; Juodkazis, Saulius

    2017-03-28

    Domestic (Bombyx mori) and wild (Antheraea pernyi) silk fibers were characterised over a wide spectral range from THz 8 cm -1 ( λ = 1.25 mm, f = 0.24 THz) to deep-UV 50 × 10 3 cm - 1 ( λ = 200 nm, f = 1500 THz) wavelengths or over a 12.6 octave frequency range. Spectral features at β-sheet, α-coil and amorphous fibroin were analysed at different spectral ranges. Single fiber cross sections at mid-IR were used to determine spatial distribution of different silk constituents and revealed an α-coil rich core and more broadly spread β-sheets in natural silk fibers obtained from wild Antheraea pernyi moths. Low energy T-ray bands at 243 and 229 cm -1 were observed in crystalline fibers of domestic and wild silk fibers, respectively, and showed no spectral shift down to 78 K temperature. A distinct 20±4 cm-1 band was observed in the crystalline Antheraea pernyi silk fibers. Systematic analysis and assignment of the observed spectral bands is presented. Water solubility and biodegradability of silk, required for bio-medical and sensor applications, are directly inferred from specific spectral bands.

  5. Modification of the glass surface property in PDMS-glass hybrid microfluidic devices.

    PubMed

    Kaneda, Shohei; Ono, Koichi; Fukuba, Tatsuhiro; Nojima, Takahiko; Yamamoto, Takatoki; Fujii, Teruo

    2012-01-01

    This paper presents a simple method to change the hydrophilic nature of the glass surface in a poly(dimethylsiloxane) (PDMS)-glass hybrid microfluidic device to hydrophobic by an extra-heating step during the fabrication process. Glass substrates bonded to a native or oxygen plasma-treated PDMS chip having microchambers (12.5 mm diameter, 110 µm height) were heated at 200°C for 3 h, and then the hydrophobicity of the glass surfaces on the substrate was evaluated by measuring the contact angle of water. By the extra-heating process, the glass surfaces became hydrophobic, and its contact angle was around 109°, which is nearly the same as native PDMS surfaces. To demonstrate the usefulness of this surface modification method, a PDMS-glass hybrid microfluidic device equipped with microcapillary vent structures for pneumatic manipulation of droplets was fabricated. The feasibility of the microcapillary vent structures on the device with the hydrophobic glass surfaces are confirmed in practical use through leakage tests of the vent structures and liquid handling for the electrophoretic separation of DNA molecules.

  6. Measurement of enhanced heat transfer coefficient with perforated twisted tape inserts during condensation of R-245fa

    NASA Astrophysics Data System (ADS)

    Khatua, A. K.; Kumar, P.; Singh, H. N.; Kumar, R.

    2016-04-01

    The experimental conductive heat transfer results for flow through inserted perforated twisted tapes in a horizontal tube during condensation of pure R-245fa vapor. The test section consisting of two separate coaxial double pipes assembled in series, acted like a counter flow heat exchanger, where the refrigerant condensed inside the inner tube by rejecting heat to the cooling water flowing inside the outer tube in reversed direction. Data for three perforated twisted tapes having constant twist ratio of 7.1 mm and pitch of perforation as 12.5, 25.0 and 37.5 mm, inserted one by one in full length of test condenser by varying refrigerant mass flux from 100 to 200 kg/m2 s in steps of 50 kg/m2 s for the range of vapor quality from 0.1 to 0.9, were collected together with flow and without insert (plain tube). It has been found that the perforated twisted tape insert having pitch of perforation equal to in order of 12.5 mm gives the highest value of average heat transfer coefficient and is of the order of 37.5 % more than that of the plain one and the correlation predicts the experimental data within an error band of ±15 %.

  7. Ion-pair supercritical fluid chromatography of metoprolol and related amino alcohols on diol silica.

    PubMed

    Gyllenhaal, Olle; Edström, Lena; Persson, Bengt-Arne

    2006-11-17

    In this paper, a chromatographic system based on carbon dioxide with methanol as mobile phase, and diol silica as stationary phase has been investigated for metoprolol and related amino alcohols by addition of strong acids to systems with triethylamine base as primary additive. Standard conditions used were 10% of methanol, containing 24 mM of acid and 18 mM of triethylamine, in carbon dioxide with a flow rate of 1.5 ml min(-1). The column dimensions were 125 mm x 4 mm I.D. and kept at 40 degrees C with a back pressure of 150 bar. Effects on selectivity were stronger with trifluoroacetic acid than with ethanesulfonic acid. From a large set of related analytes, it was shown that selectivity changes were significant when the structure close to the nitrogen of the amino alcohol analyte differed. The stability of the column in the short time perspective was examined and it showed negligible changes. For a diastereoisomeric pair, not resolved in a basic system with triethylamine nor by addition of ethanesulfonic acid, resolution improved to about 2.1 with trifluoroacetic acid. The described approach offers a way to tune the selectivity of SFC systems when amines are analyzed without the need to change stationary phase for the chromatographic separation.

  8. Alternative method to treat oroantral communication and fistula with autogenous bone graft and platelet rich firbin

    PubMed Central

    Niedzielska, Iwona; Borgiel-Marek, Halina; Różanowski, Bartosz

    2016-01-01

    Background Removing a tooth from the jaw results in the occurrence of oroantral communication in beneficial anatomic conditions or in the case of a iatrogenic effect. Popularized treatments of the oroantral communication have numerous faults. Large bone defect eliminates the chance to introduce an implant. Purpose of this work was assessment of the usefulness of autogenous bone graft and PRF in normal bone regeneration in the site of oroantral communication. Material and Methods Bone regeneration in the site of oroantral communication was assessed in 20 patients. Bone defects were supplemented autogenous bone graft from mental protuberance in 14 cases and from oblique line in 6 cases. The graft was covered with a PRF membrane. Results In the study group in all cases closure of the oroantral communication was observed. The average width of the alveolar was 13 mm and the average height was 12.5 mm. In 3 patients an average increase of alveolar height of 1.5 mm was observed. Conclusions This method may be the best option to prepare alveolar for new implant and prosthetic solutions. Key words:Oroantral communication, oroantral fistula, autogenous bone graft, bone regeneration, platelet rich fibrin. PMID:27475687

  9. Active imaging lens with real-time variable resolution and constant field of view

    NASA Astrophysics Data System (ADS)

    Parent, Jocelyn; Thibault, Simon

    2010-08-01

    We present a lens with a constant total field of view and real-time variable resolution in certain zones of interest. This smart imaging lens uses an active optical element to modify as desired the local distortion. This way, while keeping the total field of view constant, the resolution can be increased in a zone of interest, at the expense of decreasing it somewhere in the remaining part of the field of view. We first present the concept of this lens, using a deformable mirror as the active surface. Computer simulations are done with Zemax in which a magnifying power of 2 in a zone of interest representing 10% of the full field of view is achieved, using a f=12.5 mm lens and a F/# of 18. Different combinations of theses parameters would allow different performances and results. We then present experimental results of this lens with a prototype built using a ferrofluidic deformable mirror as the active element. Experimental results of a zone of increased resolution with a magnification of 1.32 and a zone of decreased resolution with a magnification of 0.80 are obtained.

  10. Quantification of airway morphometry: the effect of CT acquisition and reconstruction parameters

    NASA Astrophysics Data System (ADS)

    Leader, J. Ken; Zheng, Bin; Sciurba, Frank C.; Coxson, Harvey O.; Fuhrman, Carl R.; McMurray, Jessica M.; Park, Sang C.; Maitz, Glenn S.; Gur, David

    2007-03-01

    This study measured the accuracy of our airway quantification scheme using phantoms airway under different CT protocols. Airway remodeling is associated with several thoracic diseases (e.g., chronic bronchitis, asthma, and bronchiectasis), and, therefore, quantification of airway remodeling may have wide clinical application. Our scheme assigns pixels partial membership in the airway wall and lumen based on the pixel's HU value, which is intended to account for partial volume averaging inherent in CT image reconstruction. Twenty-four phantom airways with an outer diameter from 2.6 to 14.0 mm and wall thicknesses from 0.5 to 2.0 mm were analyzed. The absolute differences between measurements supplied by the manufacture and computed from CT images acquired at 40 mAs and reconstructed at 1.25 mm thickness using GE's "soft" and "lung" reconstruction kernels for lumen area ranged from 1.4% to 49.3% and 0.4% to 33.0%, respectively, and for wall area ranged from 0.3% to 118.0% and 2.1 to 92.9%, respectively. Accuracy typically improved as the kernel's spatial frequency increased. Airways whose wall thickness was close to the pixels dimensions were challenging to quantify. The partial membership assignment of our airway quantification accurately computed airway morphometry across a range of phantom airway sizes.

  11. Effects of surface roughness and chrome plating of punch tips on the sticking tendencies of model ibuprofen formulations.

    PubMed

    Roberts, Matthew; Ford, James L; MacLeod, Graeme S; Fell, John T; Smith, George W; Rowe, Philip H

    2003-09-01

    The sticking of three model ibuprofen-lactose formulations with respect to compaction force and the surface quality of the upper punch were assessed. Compaction was performed at 10, 25 or 40 kN using an instrumented single-punch tablet press. Two sets of 12.5-mm flat-faced punches were used to evaluate the influence of surface quality. A third set of chrome-plated tooling was also used. Surface profiles (Taylor Hobson Talysurf 120) of the normal tooling upper punches indicated a large difference in quality. The punches were subsequently classified as old (Ra = 0.33 microm) or new (Ra = 0.04 microm) where Ra is the mean of all positive deviations from zero. Surface profiles of sample tablets were also obtained. Following compaction, ibuprofen attached to the face was quantified by spectroscopy. Punch surface roughness, compaction force and the blend composition were all significant factors contributing to sticking. Chrome plating of punch faces increased sticking at a low compaction force but decreased sticking at higher forces. Surface roughness of the tablets did not correlate with the corresponding data for sticking, indicating that this is not a suitable method of quantifying sticking.

  12. Development of a 55 μm pitch 8 inch CMOS image sensor for the high resolution NDT application

    NASA Astrophysics Data System (ADS)

    Kim, M. S.; Kim, G.; Cho, G.; Kim, D.

    2016-11-01

    A CMOS image sensor (CIS) with a large area for the high resolution X-ray imaging was designed. The sensor has an active area of 125 × 125 mm2 comprised with 2304 × 2304 pixels and a pixel size of 55 × 55 μm2. First batch samples were fabricated by using an 8 inch silicon CMOS image sensor process with a stitching method. In order to evaluate the performance of the first batch samples, the electro-optical test and the X-ray test after coupling with an image intensifier screen were performed. The primary results showed that the performance of the manufactured sensors was limited by a large stray capacitance from the long path length between the analog multiplexer on the chip and the bank ADC on the data acquisition board. The measured speed and dynamic range were limited up to 12 frame per sec and 55 dB respectively, but other parameters such as the MTF, NNPS and DQE showed a good result as designed. Based on this study, the new X-ray CIS with ~ 50 μm pitch and ~ 150 cm2 active area are going to be designed for the high resolution X-ray NDT equipment for semiconductor and PCB inspections etc.

  13. [Changes in intraocular pressure depending on posture].

    PubMed

    Barac, Ramona; Pop, Monica; Tătaru, C; Gheorghe, A; Bădescu, Silvia; Stanciu, Maria; Burcea, M

    2014-01-01

    Glaucoma is an important eye disease that, left untreated, causes irreversible blindness by affecting optic nerve threads. Decreasing intraocular pressure and maintaining it at a low level throughout the day is one of the objectives of antiglaucoma therapy. This is a prospective study conducted on a sample of 80 patients who presented at "Emergency Eye Hospital" Bucharest between 1st of December 2013 30th of July 2014. Patients were divided into two groups: 40 patients with glaucoma and 40 patients without glaucoma (control group). THE OBJECTIVE OF THE STUDY: To determine changes in intraocular pressure that may occur depending on body posture and the correlations between changes in intraocular pressure and glaucoma, obesity, hypertension. These IOP changes may be important in the progression of glaucoma regarding that one third of our time is spent on supine position during night. RESULTS AND CONCLUZIONS: IOP varies from sitting down to supine position. IOP increases in supine in most patients (with or without glaucoma) with an average of 1.25 mmHg. The increase among patients with glaucoma is higher (1.67 mmHg) compared to those without glaucoma (0.82 mmHg). In patients with hypertension and glaucoma, IOP increased with 2.62 mmHg. In patients with hypertension and obesity IOP increased with 2.5 mmHg.

  14. Femtosecond laser induced nanostructuring for surface enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Messaoudi, H.; Das, S. K.; Lange, J.; Heinrich, F.; Schrader, S.; Frohme, M.; Grunwald, R.

    2014-03-01

    The formation of periodical nanostructures with femtosecond laser pulses was used to create highly efficient substrates for surface-enhanced Raman spectroscopy (SERS). We report about the structuring of silver and copper substrates and their application to the SERS of DNA (herring sperm) and protein molecules (egg albumen). The maximum enhancement factors were found on Ag substrates processed with the second harmonic generation (SHG) of a 1-kHz Ti:sapphire laser and structure periods near the SHG wavelength. In the case of copper, however, the highest enhancement was obtained with long-period ripples induced with at fundamental wavelength. This is explained by an additional significant influence of nanoparticles on the surface. Nanostructured areas in the range of 1.25 mm2 were obtained in 10 s. The surfaces were characterized by scanning electron microscopy, Fast Fourier Transform and Raman spectroscopy. Moreover, the role of the chemical modification of the metal structures is addressed. Thin oxide layers resulting from working in atmosphere which improve the biocompatibility were indicated by vibration spectra. It is expected that the detailed study of the mechanisms of laser-induced nanostructure formation will stimulate further applications of functionalized surfaces like photocatalysis, selective chemistry and nano-biology.

  15. Use of subatmospheric pressure to prevent progression of partial-thickness burns in a swine model.

    PubMed

    Morykwas, M J; David, L R; Schneider, A M; Whang, C; Jennings, D A; Canty, C; Parker, D; White, W L; Argenta, L C

    1999-01-01

    The poorly understood, complex series of events that follows thermal injury frequently results in progressive loss of tissue. The concept of reversing this distinctive series of events has focused on the zone of stasis. Tissues in the zone of stasis that surround burn injuries usually die over a period of 48 to 72 hours postinjury, resulting in a more severe injury. Application of a controlled subatmospheric pressure (125 mm Hg) in an artificially closed space to partial-thickness burns in pigs significantly decreased the maximum depth of cellular death under the burn when the pressure was applied within 12 hours after burn creation (depth of control burns = 0.885 +/- 0.115 mm; subatmospheric pressure treated burns (0-hour delay) = 0.095 +/- 0.025 mm). A decrease in the depth of cell death was noted when subatmospheric pressure was applied for as little as 6 hours. In summary, the application of the negative pressure to partial-thickness burn injuries prevented progression of the wound to a deeper injury in this experimental pig model. A 12-hour working window exists between injury and treatment with reduced pressure, with an application time of as little as 6 hours for successful prevention of injury progression. This technique may represent a new, inexpensive, 'low tech' method for the treatment of partial-thickness burn injuries.

  16. Clinical applications of CO2 lasers: clinical cases

    NASA Astrophysics Data System (ADS)

    Sinibaldi, Kenneth R.

    1994-09-01

    The most common surgery performed in our clinic with the CO2 laser is the cutting and vaporization of neoplasms associated with the head and neck, in particular, the squamous cell carcinoma in the cat. A majority of the tumors are malignant and 50% are metastatic at the time of presentation for surgery. Experience has taught us that early detection and removal with the CO2 laser affords the best prognosis. To date, roughly 100 cases have been treated with the CO2 laser. The success rate in the dog is not as rewarding as in the cat. Most cases were done with 5 - 10 watts of power continuous or pulsed wave, using a 125 mm or 50 mm handpiece. The laser beam was focused or defocused to adjust for cutting, vaporization, and coagulation. No post-op care of the wounds was recommended. Other small neoplasms in and around the ears, head, and neck can also be removed easily with the CO2 laser.

  17. A Re-assessment of Minocycline as a Neuroprotective Agent in a Rat Spinal Cord Contusion Model

    PubMed Central

    Pinzon, Alberto; Marcillo, Alexander; Quintana, Ada; Stamler, Sarah; Bunge, Mary Bartlett; Bramlett, Helen M.; Dietrich, W. Dalton

    2009-01-01

    This study was initiated due to an NIH “Facilities of Research-Spinal Cord Injury” contract to support independent replication of published studies that could be considered for a clinical trial in time. Minocycline has been shown to have neuroprotective effects in models of central nervous system injury, including in a contusive spinal cord injury (SCI) model at the thoracic level. Beneficial effects of minocycline treatment included a significant improvement in locomotor behavior and reduced histopathological changes (Lee et al., 2003) To verify these important observations, we repeated this study in our laboratory. The NYU (MASCIS) Impactor was used to produce a moderate cord lesion at the vertebral level T9–T10 (height 12.5 mm, weight 10 g), (n=45), followed by administration of minocycline, 90mg/kg (group 1: minocycline IP, n=15; group 2: minocycline IV, n=15; group 3: vehicle IP, n=8; group 4: vehicle IV, n=7) immediately after surgery and followed by two more doses of 45 mg/kg/IP at 12 hrs and 24 hrs. Open field locomotion (BBB) and subscores were examined up to 6 weeks after SCI and cords were processed for quantitative histopathological analysis. Administration of minocycline after SCI did not lead to significant behavioral or histopathological improvement. Although positive effects with minocycline have been reported in several animal models of injury with different drug administration schemes, the use of minocycline following contusive SCI requires further investigation before clinical trials are implemented. PMID:18838063

  18. Intraluminal and intracavitary vacuum therapy for esophageal leakage: a new endoscopic minimally invasive approach.

    PubMed

    Loske, G; Schorsch, T; Müller, C

    2011-06-01

    Endoscopic treatment by placement of a vacuum sponge drainage system is a new option in the management of leakages in the digestive tract. We now distinguish between two treatment variants: the intracavitary and intraluminal techniques. A drainage system comprising an appropriately trimmed polyurethane foam sponge and a gastric-type tube is either placed through the esophageal defect into an extraluminal wound cavity (intracavitary method), or directly onto the defect with the sponge remaining within the esophageal lumen (intraluminal method). Continuous negative pressure of 125 mmHg is then applied, resulting in stabilizing of the sponge and continuous drainage and sealing of the defect. We report a case series of 14 patients, presenting the full range of possible esophageal defects that were successfully treated with either intracavitary or intraluminal vacuum therapy. Complete healing of the esophageal defect was achieved in 13 patients; one patient died due to fulminant pseudomembranous colitis while the esophageal defect was nearly healed. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Temporary hair loss using the long-pulsed alexandrite laser at 20 milliseconds.

    PubMed

    Raulin, C; Greve, B

    2000-03-01

    Facial hypertrichosis presents an enormous psychological burden for women. Temporary hair removal (waxing, plucking, etc.) and electrolysis are prolonged and unsatisfactory methods of treatment. For a few years several laser systems with varying wavelengths, pulse durations and energy fluences have been used successfully in laser epilation. In the retrospective study on hand, we report on results of 30 female patients with hypertrichosis in the facial area treated with the long pulse alexandrite laser at 20 msec (Cynosure PhotoGenica LPIR/Apogee; 755 nm; 20 msec; up to 30 J/cm2; 10 or 12.5 mm beam diameter) over an 18 month treatment period. After an average of 8 treatments, an average clearance rate of 75% could be achieved. Fair hair (white/blond/red) only showed a clearance rate of 10%. Hypo- and hyperpigmentation did not appear. The most frequent adverse effects were the occasional appearance of scattered crusting (17%), which healed without consequences, and folliculitis (13%). The average post-treatment observation time lasted 3.25 months. The long-pulsed alexandrite laser at a pulse duration of 20 msec is an effective and safe method of treatment of hypertrichosis in the facial region of women. Black hair responds considerably better to the laser treatment than fair hair. A longer post-treatment observation time is necessary, though, in order to provide evidence for the permanence of the success of the method.

  20. Propagation of Axially Symmetric Detonation Waves

    SciTech Connect

    Druce, R L; Roeske, F; Souers, P C; Tarver, C M; Chow, C T S; Lee, R S; McGuire, E M; Overturf, G E; Vitello, P A

    2002-06-26

    We have studied the non-ideal propagation of detonation waves in LX-10 and in the insensitive explosive TATB. Explosively-driven, 5.8-mm-diameter, 0.125-mm-thick aluminum flyer plates were used to initiate 38-mm-diameter, hemispherical samples of LX-10 pressed to a density of 1.86 g/cm{sup 3} and of TATB at a density of 1.80 g/cm{sup 3}. The TATB powder was a grade called ultrafine (UFTATB), having an arithmetic mean particle diameter of about 8-10 {micro}m and a specific surface area of about 4.5 m{sup 2}/g. Using PMMA as a transducer, output pressure was measured at 5 discrete points on the booster using a Fabry-Perot velocimeter. Breakout time was measured on a line across the booster with a streak camera. Each of the experimental geometries was calculated using the Ignition and Growth Reactive Flow Model, the JWL++ Model and the Programmed Burn Model. Boosters at both ambient and cold (-20 C and -54 C) temperatures have been experimentally and computationally studied. A comparison of experimental and modeling results is presented.

  1. Anomalous laser deflection phenomena based on the interaction of electro-optic and graded refractivity effect in Cu:KTN crystal

    NASA Astrophysics Data System (ADS)

    Wang, Xuping; Liu, Bing; Yang, Yuguo; Zhang, Yuanyuan; Lv, Xianshun; Hong, Guanglie; Shu, Rong; Yu, Haohai; Wang, Jiyang

    2014-12-01

    In this paper, we report an abnormal laser deflection phenomena based on quadratic electro-optic effect in copper doped KTN crystal. Cu:KTa0.62Nb0.38O3 block with size a×b×c = 2.8mm×2.6mm×12.5mm was used as beam deflection element. 75mrad beam deflection angle were observed under 1KV voltage when the laser beam across the c direction of the sample at room temperature. The special features of our experiment are that the direction of laser beam deflect perpendicular to the electric field direction, and the angular size and direction of the deflection beam remain unchanged when the electric field direction reverse. We believe that the interaction of graded refractivity and electro-optic effect leads to these special features. Besides of the special deflection mode, the deflection efficiency of our experiment also reached the world advanced level.

  2. Anthropomorphic phantoms for assessment of strain imaging methods involving saline-infused sonohysterography.

    PubMed

    Hobson, Maritza A; Madsen, Ernest L; Frank, Gary R; Jiang, Jingfeng; Shi, Hairong; Hall, Timothy J; Varghese, Tomy

    2008-10-01

    Two anthropomorphic uterine phantoms were developed that allow assessment and comparison of strain imaging systems adapted for use with saline-infused sonohysterography (SIS). Tissue-mimicking (TM) materials consist of dispersions of safflower oil in gelatin. TM fibroids are stiffer than the TM myometrium/cervix, and TM polyps are softer. The first uterine phantom has 3-mm-diameter TM fibroids distributed randomly in TM myometrium. The second uterine phantom has a 5-mm and 8-mm spherical TM fibroid, in addition to a 5-mm spherical and a 12.5-mm-long (medicine capsule-shaped) TM endometrial polyp protruding into the endometrial cavity; also, a 10-mm spherical TM fibroid projects from the serosal surface. Strain images using the first phantom show the stiffer 3-mm TM fibroids in the myometrium. Results from the second uterine phantom show that, as expected, parts of inclusions projecting into the uterine cavity will appear very stiff, whether they are stiff or soft. Results from both phantoms show that although there is a five-fold difference in the Young's moduli values, there is not a significant difference in the strain in the transition from the TM myometrium to the TM fat. These phantoms allow for realistic comparison and evolution of SIS strain imaging techniques and can aid clinical personnel to develop skills for SIS strain imaging.

  3. A feasibility study of temperature rise measurement in a tissue phantom as an alternative way for characterization of the therapeutic high intensity focused ultrasonic field.

    PubMed

    Chen, Di; Fan, Tingbo; Zhang, Dong; Wu, Junru

    2009-12-01

    The feasibility that temperature field measurements in vitro as an alternative way to characterize the high intensity focused ultrasound (HIFU) field used in therapeutic applications has been explored in a phantom study. Thermocouples (copper-constantan, diameter 0.125 mm) are embedded in a phantom filled with tissue mimicking material that simulates the thermal and acoustic properties of soft-tissue. The temperature rises as a function of ultrasound exposure time near the focus of a HIFU transducer (1.1 MHz, active radius a=32 mm, geometric focal length=62 mm) of various acoustic powers up to 30 W are measured and compared with predicted values using a simple nonlinear Gaussian model. The experimental results can be explained well by the model if no acoustic cavitation takes place. When the acoustic power become higher (>5 W) and the local temperature elevation >15 degrees C and the local temperature is >40 degrees C at the focal point, cavitation vapor bubbles appear. The presence of the cavitation bubbles may increase the temperature rise rate initially. The bubble aggregates may form along the beam axis under sonication and then eventually makes the temperature elevation reach a saturated value. When acoustic cavitation occurs, the bubble-assisted enhancement of the initial temperature rise (exposure time t<2s) can still be predicted by the theory.

  4. Flexible laser welding of tailored blanks in small batch series

    NASA Astrophysics Data System (ADS)

    Bagger, Claus B.; Olsen, Flemming O.

    2003-03-01

    In a EU Craft project including eight partners in five countries, the most important aspects regarding efficient and low cost manufacture by small and medium sized enterprises (SME) of tailored blanks has been systematically investigated. In this paper, small batch series laser welding of tailored blanks in SME will be described. This includes the design, development and systematic use of a flexible and low cost clamping device as well as the practical experience obtained on the job shop through systematic optimization of welding of tailored blanks with even and uneven thickness (0.75 and 1.25 mm). A clamping device that is able to hold finished parts up to 1 x 1 m is successfully manufactured and tested. A special arrangement with alignment needles along the weld line is used to precisely position the sheets. These needles are turned into the clamping device during welding, where root shielding is employed. Hydraulic presses hold down the sheets, so they move less than 0.01 mm during welding. High quality tailored blank welds are successfully manufactured in ten different combinations, including mild steel and medium strength steel with even and uneven thickness with and without zinc coating.

  5. Deoxycytidylate deaminase. Properties of the enzyme from cultured kidney cells of baby hamster

    PubMed Central

    Rolton, Hilary A.; Keir, Hamish M.

    1974-01-01

    dCMP deaminase was partially purified from BHK-21/C13 cells grown in culture. The molecular weight of the enzyme was estimated by gel filtration and gradient centrifugation to be 130000 and 115000 respectively. The enzyme had a pH optimum of 8.4. Its activity versus substrate concentration curve was sigmoid, the substrate concentration at half-maximal velocity being 4.4mm. dCTP activated the deaminase maximally at 40μm, gave a hyperbolic curve for activity versus dCMP concentration and a Km value for dCMP of 0.91mm. dCTP activation required the presence of Mg2+ or Mn2+ ions. dTTP inhibited the deaminase maximally at 15μm; the inhibition required the presence of Mg2+ or Mn2+ ions. The enzyme was very heat-labile but could be markedly stabilized by dCTP at 0.125mm and ethylene glycol at 20% (v/v). PMID:4455201

  6. Methanol Droplet Extinction in Carbon-Dioxide-Enriched Environments in Microgravity

    NASA Technical Reports Server (NTRS)

    Hicks, Michael C.; Nayagam, Vedha; Williams, Forman A.

    2010-01-01

    Diffusive extinction of methanol droplets with initial diameters between 1.25 mm and 1.72 mm, burning in a quiescent microgravity environment at one atmosphere pressure, was obtained experimentally for varying levels of ambient carbon-dioxide concentrations with a fixed oxygen concentration of 21% and a balance of nitrogen. These experiments serve as precursors to those which are beginning to be performed on the International Space Station and are motivated by the need to understand the effectiveness of carbon-dioxide as a fire suppressant in low-gravity environments. In these experiments, the flame standoff distance, droplet diameter, and flame radiation are measured as functions of time. The results show that the droplet extinction diameter depends on both the initial droplet diameter and the ambient concentration of carbon dioxide. Increasing the initial droplet diameter leads to an increased extinction diameter, while increasing the carbon-dioxide concentration leads to a slight decrease in the extinction diameter. These results are interpreted using a critical Damk hler number for extinction as predicted by an earlier theory, which is extended here to be applicable in the presence of effects of heat conduction along the droplet support fibers and of the volume occupied by the support beads

  7. A 3D High Frequency Array Based 16 Channel Photoacoustic Microscopy System for In Vivo Micro-vascular Imaging

    PubMed Central

    Zemp, Roger; Yen, Jesse; Wang, L.V.; Shung, K. Kirk

    2009-01-01

    This paper discusses the design of a novel photoacoustic microscopy imaging system with promise for studying the structure of tissue microvasculature for applications in visualizing angiogenesis. A new sixteen channel analog and digital high frequency array based photoacoustic microscopy system (PAM) was developed using an Nd:YLF pumped tunable dye laser, a 30MHz piezo composite linear array transducer and a custom multi-channel receiver electronics system. Using offline delay and sum beamforming and beamsteering, phantom images were obtained from a 6µm carbon fiber in water at a depth of 8mm. The measured -6dB lateral and axial spatial resolution of the system was 100±5µm and 45±5µm, respectively. The dynamic focusing capability of the system was demonstrated by imaging a composite carbon fiber matrix through a 12.5mm imaging depth. Next, 2-D in vivo images were formed of vessels around 100µm in diameter in the human hand. 3-D in vivo images were also formed of micro-vessels 3mm below the surface of the skin in two Sprague Dawley rats. PMID:19131292

  8. Cryogenic Testing of Different Seam Concepts for Multilayer Insulation Systems

    NASA Technical Reports Server (NTRS)

    Johnson, Wesley L.; Fesmire, J. E.

    2009-01-01

    Recent testing in a cylindrical, comparative cryostat at the Cryogenics Test Laboratory has focused on various seam concepts for multilayer insulation systems. Three main types of seams were investigated: straight overlap, fold-over, and roll wrapped. Each blanket was comprised of 40 layer pairs of reflector and spacer materials. The total thickness was approximately 12.5-mm, giving an average layer density of 32 layers per centimeter. The blankets were tested at high vacuum, soft vacuum, and no vacuum using liquid nitrogen to maintain the cold boundary temperature at 77 K. Test results show that all three seam concepts are all close in thermal performance; however the fold-over method provides the lowest heat flux. For the first series of tests, seams were located 120 degrees around the circumference of the cryostat from the previous seam. This technique appears to have lessened the degradation of the blanket due to the seams. In a follow-on test, a 20 layer blanket was tested in a roll wrapped configuration and then cut down the side of the cylinder, taped together, and re-tested. This test result shows the thermal performance impact of having the seams all in one location versus having the seams clocked around the vessel. This experimental investigation indicates that the method of joining the seams in multilayer insulation systems is not as critical as the quality of the installation process.

  9. Preliminary data on growth and reproduction of Cobitis simplicispina from Turkey.

    PubMed

    Ekmekçi, Fitnat Güler; Erk'akan, Füsun

    2003-01-01

    Preliminary data on growth and reproduction parameters of Cobitis simplicispina from Darýözü Creek in the Kizilimak basin in Kirşehir-Turkey were presented. The age of the specimens collected during a period between March and June 2002, ranged from 1+ to 4+. The observed maximum total length of males is 91.8 mm, and 97 mm for females. The von Bertalanffy equation for male and female specimens was found to be Lt=93.01(1-exp(-0.408(t+0.821))) and Lt=94.42(1-exp(-0.488(t+0.458))), respectively. The length-weight relationship was expressed as log W= 3.009x SL -5.171 when all specimens were taken into account. The range of absolute fecundity extended from 320 to 2141 eggs and the diameter of ripe eggs varied between 1.00 and 1.25 mm. The gonadosomatic index suggested that spawning took place in April.

  10. Effect of layer thickness and printing orientation on mechanical properties and dimensional accuracy of 3D printed porous samples for bone tissue engineering.

    PubMed

    Farzadi, Arghavan; Solati-Hashjin, Mehran; Asadi-Eydivand, Mitra; Abu Osman, Noor Azuan

    2014-01-01

    Powder-based inkjet 3D printing method is one of the most attractive solid free form techniques. It involves a sequential layering process through which 3D porous scaffolds can be directly produced from computer-generated models. 3D printed products' quality are controlled by the optimal build parameters. In this study, Calcium Sulfate based powders were used for porous scaffolds fabrication. The printed scaffolds of 0.8 mm pore size, with different layer thickness and printing orientation, were subjected to the depowdering step. The effects of four layer thicknesses and printing orientations, (parallel to X, Y and Z), on the physical and mechanical properties of printed scaffolds were investigated. It was observed that the compressive strength, toughness and Young's modulus of samples with 0.1125 and 0.125 mm layer thickness were more than others. Furthermore, the results of SEM and μCT analyses showed that samples with 0.1125 mm layer thickness printed in X direction have more dimensional accuracy and significantly close to CAD software based designs with predefined pore size, porosity and pore interconnectivity.

  11. Development of the Gliding Hole of the Dynamics Compression Plate

    NASA Astrophysics Data System (ADS)

    Salim, U. A.; Suyitno; Magetsari, R.; Mahardika, M.

    2017-02-01

    The gliding hole of the dynamics compression plate is designed to facilitate relative movement of pedicle screw during surgery application. The gliding hole shape is then geometrically complex. The gliding hole manufactured using machining processes used to employ ball-nose cutting tool. Then, production cost is expensive due to long production time. This study proposed to increase productivity of DCP products by introducing forming process (cold forming). The forming process used to involve any press tool devices. In the closed die forming press tool is designed with little allowance, then work-pieces is trapped in the mould after forming. Therefore, it is very important to determine hole geometry and dimensions of raw material in order to success on forming process. This study optimized the hole sizes with both geometry analytics and experiments. The success of the forming process was performed by increasing the holes size on the raw materials. The holes size need to be prepared is diameter of 5.5 mm with a length of 11.4 mm for the plate thickness 3 mm and diameter of 6 mm with a length of 12.5 mm for the plate thickness 4 mm.

  12. Aerodynamic performance of a vibrating piezoelectric fan under varied operational conditions

    NASA Astrophysics Data System (ADS)

    Stafford, J.; Jeffers, N.

    2014-07-01

    This paper experimentally examines the bulk aerodynamic performance of a vibrating fan operating in the first mode of vibration. The influence of operating condition on the local velocity field has also been investigated to understand the flow distribution at the exit region and determine the stalling condition for vibrating fans. Fan motion has been generated and controlled using a piezoelectric ceramic attached to a stainless steel cantilever. The frequency and amplitude at resonance were 109.4 Hz and 12.5 mm, respectively. A test facility has been developed to measure the pressure-flow characteristics of the vibrating fan and simultaneously conduct local velocity field measurements using particle image velocimetry. The results demonstrate the impact of system characteristics on the local velocity field. High momentum regions generated due to the oscillating motion exist with a component direction that is tangent to the blade at maximum displacement. These high velocity zones are significantly affected by increasing impedance while flow reversal is a dominant feature at maximum pressure rise. The findings outlined provide useful information for design of thermal management solutions that may incorporate this air cooling approach.

  13. Design and Construction of a Gamma Reaction History Diagnostic for the National Ignition Facility

    SciTech Connect

    Malone, R M; Evans, S C; Frogget, B C; Herrmann, H W; Kaufman, M I; Kim, Y H; Mack, J M; McGillivray, K D; Palagi, M; Stoeffl, W; Tibbitts, A; Tunnell, T W; Young, C S

    2009-10-22

    Gas Cherenkov detectors have been used to convert fusion gammas into photons to record gamma reaction history measurements. These gas detectors include a converter, pressurized gas volume, relay collection optics, and a photon detector. A novel design for the National Ignition Facility (NIF) using 90° off-axis parabolic mirrors efficiently collects signal from fusion gammas with 8-ps time dispersion. Fusion gammas are converted to Compton electrons, which generate broadband Cherenkov light (response is from 250 to 700 nm) in a pressurized gas cell. This light is relayed into a high-speed detector using three parabolic mirrors. The relay optics collect light from a 125-mm-diameter by 600-mm-long interchangeable gas (CO2 or SF6) volume. The parabolic mirrors were electroformed instead of diamond turned to reduce scattering of the UV light. All mirrors are bare aluminum coated for maximum reflectivity. This design incorporates a 4.2-ns time delay that allows the detector to recover from prompt radiation before it records the gamma signal. At NIF, a cluster of four channels will allow for increased dynamic range, as well as different gamma energy thresholds.

  14. Spectrally resolved bioluminescence tomography using the reciprocity approach

    PubMed Central

    Dehghani, Hamid; Davis, Scott C.; Pogue, Brian W.

    2008-01-01

    Spectrally resolved bioluminescence optical tomography is an approach to recover images of, for example, Luciferase activity within a volume using multiwavelength emission data from internal bioluminescence sources. The underlying problem of uniqueness associated with nonspectrally resolved intensity-based bioluminescence tomography is demonstrated and it is shown that using a non-negative constraint inverse algorithm, an accurate solution for the source distribution can be calculated from the measured data. Reconstructed images of bioluminescence are presented using both simulated complex and heterogeneous small animal models as well as real multiwavelength data from a tissue-simulating phantom. The location of the internal bioluminescence source using experimental data is obtained with 0.5 mm accuracy and it is shown that small (2.5 mm diameter) sources of up to 12.5 mm deep, within a complex mouse model, can be resolved accurately using a single view data collection strategy. Finally, using the reciprocity approach for image reconstruction, a dramatic improvement in computational time is shown without loss to image accuracy with both experimental and simulated data, potentially reducing computing time from 402 to 3.75 h. PMID:19070220

  15. Behavior of turbulent gas jets in an axisymmetric confinement

    NASA Technical Reports Server (NTRS)

    So, R. M. C.; Ahmed, S. A.

    1985-01-01

    The understanding of the mixing of confined turbulent jets of different densities with air is of great importance to many industrial applications, such as gas turbine and Ramjet combustors. Although there have been numerous studies on the characteristics of free gas jets, little is known of the behavior of gas jets in a confinement. The jet, with a diameter of 8.73 mm, is aligned concentrically in a tube of 125 mm diameter, thus giving a confinement ratio of approximately 205. The arrangement forms part of the test section of an open-jet wind tunnel. Experiments are carried out with carbon dioxide, air and helium/air jets at different jet velocities. Mean velocity and turbulence measurements are made with a one-color, one-component laser Doppler velocimeter operating in the forward scatter mode. Measurements show that the jets are highly dissipative. Consequently, equilibrium jet characteristics similar to those found in free air jets are observed in the first two diameters downstream of the jet. These results are independent of the fluid densities and velocities. Decay of the jet, on the other hand, is a function of both the jet fluid density and momentum. In all the cases studied, the jet is found to be completely dissipated in approximately 30 jet diameters, thus giving rise to a uniform flow with a very high but constant turbulence field across the confinement.

  16. Effects of a commercial orthodontic debonding agent upon the surface microhardness of two orthodontic bonding resins.

    PubMed

    Larmour, C J; Chadwick, R G

    1995-02-01

    The bonding techniques employed in orthodontic practice differ from those used in restorative dentistry for, upon the completion of treatment, the appliance is removed. This necessitates breaking the resin/enamel bond. Ideally a smooth, undamaged enamel surface free from all traces of bonding agent should result. Regrettably, however, this ideal is rarely achieved. This investigation assessed the effects of a commercial debonding agent (P-de-A, Oradent Ltd, Eton, Berks, UK), derived from peppermint oil, upon the surface microhardness of two orthodontic resins (Orthodontic Concise and Transbond, both 3M, St Paul, MN, USA). Twenty discs (10 mm diameter x 1.25 mm deep) of each resin were fabricated and, following 1 week's storage in distilled water at 37 degrees C, were allocated to application groups composed of four specimens. The mean initial surface hardness of each group was then determined prior to the application of P-de-A for one of: 30, 60, 90, 120 and 180 s. The hardness was then remeasured. One-way analyses of variance were performed upon the mean initial and final hardness data and revealed only a significant (P < 0.05) reduction in surface hardness following the 180 s application of P-de-A to Orthodontic Concise. We were therefore unable to find little evidence to suggest that the agent facilitates debonding by a softening mechanism and further work is required to elucidate the means whereby orthodontic debonding and 'clean-up' of residual composite, as reported by others, is facilitated.

  17. Simultaneous micellar LC determination of lidocaine and tolperisone.

    PubMed

    Youngvises, Napaporn; Liawruangrath, Boonsom; Liawruangrath, Saisunee

    2003-03-26

    A micellar liquid chromatography (MLC) procedure was developed for the simultaneous separation and determination of lidocaine hydrochloride (LD HCl) and tolperisone hydrochloride (TP HCl) using a short-column C18 (12.5 mm x 4.6 mm, 5 microm), sodium dodecyl sulfate (SDS) with a small amount of isopropanol, and diode array detector. The optimum conditions for the simultaneous determination of both drugs were 0.075 mol l(-1) SDS-7.5% (v/v) isopropanol with a flow rate of 0.7 ml min(-1) and detection at 210 nm. The LOD (2S/N) of LD HCl was 0.73 ng 20 microl(-1), whereas that of TP HCl was 1.43 ng 20 microl(-1). The calibration curves for LD HCl and TP HCl were linear over the ranges 0.125-500 microg ml(-1) (r(2)=0.9999) and 1.00-500 microg ml(-1) (r(2)=0.9997), respectively. The %recoveries of both drugs were in the range 98-103% and the %RSD values were less than 2. The proposed method has been successfully applied to the simultaneous determination of TP HCl and LD HCl in various pharmaceutical preparations.

  18. Weight Estimation Tool for Children Aged 6 to 59 Months in Limited-Resource Settings

    PubMed Central

    2016-01-01

    .33%); proportion of estimates accurate to within ± 25% of true weight was 97.36% (95% CI 97.40%, 97.46%); and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-2.15 kg; 2.24 kg). The height model fitted for MUAC classes was accurate and precise. For MUAC < 115 mm, the proportion of estimates accurate to within ± 25% of true weight was 97.15% (95% CI 96.90%, 97.42%) and the Bland-Altman bias and 95% limits of agreement were 0.08 kg and (-1.21 kg; 1.37 kg). For MUAC between 115 and 125 mm, the proportion of estimates accurate to within ± 25% of true weight was 98.93% (95% CI 98.82%, 99.03%) and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-1.15 kg; 1.24 kg). For MUAC > 125 mm, the proportion of estimates accurate to within ± 25% of true weight was 98.33% (95% CI 98.29%, 98.37%) and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-2.08 kg; 2.19 kg). Conclusions and Relevance Models estimating weight from height alone and height with MUAC class in children aged 6–59 months in a database from low-to-middle income countries were more accurate and precise than previous weight estimation tools. A height-based weight estimation tape stratified according to MUAC classes is proposed for children aged 6–59 months in limited-resource settings. PMID:27529816

  19. TH-E-17A-04: Geometric Validation of K-Space Self-Gated 4D-MRI Vs. 4D-CT Using A Respiratory Motion Phantom

    SciTech Connect

    Yue, Y; Fan, Z; Yang, W; Pang, J; McKenzie, E; Deng, Z; Tuli, R; Sandler, H; Li, D; Fraass, B

    2014-06-15

    Purpose: 4D-CT is often limited by motion artifacts, low temporal resolution, and poor phase-based target definition. We recently developed a novel k-space self-gated 4D-MRI technique with high spatial and temporal resolution. The goal here is to geometrically validate 4D-MRI using a MRI-CT compatible respiratory motion phantom and comparison to 4D-CT. Methods: 4D-MRI was acquired using 3T spoiled gradient echo-based 3D projection sequences. Respiratory phases were resolved using self-gated k-space lines as the motion surrogate. Images were reconstructed into 10 temporal bins with 1.56×1.56×1.56mm3. A MRI-CT compatible phantom was designed with a 23mm diameter ball target filled with highconcentration gadolinium(Gd) gel embedded in a 35×40×63mm3 plastic box stabilized with low-concentration Gd gel. The whole phantom was driven by an air pump. Human respiratory motion was mimicked using the controller from a commercial dynamic phantom (RSD). Four breathing settings (rates/depths: 10s/20mm, 6s/15mm, 4s/10mm, 3s/7mm) were scanned with 4D-MRI and 4D-CT (slice thickness 1.25mm). Motion ground-truth was obtained from input signals and real-time video recordings. Reconstructed images were imported into Eclipse(Varian) for target contouring. Volumes and target positions were compared with ground-truth. Initial human study was investigated on a liver patient. Results: 4D-MRI and 4D-CT scans for the different breathing cycles were reconstructed with 10 phases. Target volume in each phase was measured for both 4D-CT and 4D-MRI. Volume percentage difference for the 6.37ml target ranged from 6.67±5.33 to 11.63±5.57 for 4D-CT and from 1.47±0.52 to 2.12±1.60 for 4D-MRI. The Mann-Whitney U-test shows the 4D-MRI is significantly superior to 4D-CT (p=0.021) for phase-based target definition. Centroid motion error ranges were 1.35–1.25mm (4D-CT), and 0.31–0.12mm (4D-MRI). Conclusion: The k-space self-gated 4D-MRI we recently developed can accurately determine phase-based target volume while avoiding typical motion artifacts found in 4D-CT, and is being further studied for use in GI targeting and motion management. This work supported in part by grant 1R03CA173273-01.

  20. Critical bandwidth and consonance: their operational definitions in relation to cochlear nonlinearity and combination tones.

    PubMed

    Greenwood, D D

    1991-08-01

    A recent paper (Greenwood, 1990) reviewed cochlear coordinates in several species in relation to empirical frequency-position functions (Greenwood, 1961b, 1974b), one of which well fits the Békésy-Skarstein human cochlear map (Békésy, 1960; Kringlebotn et al, 1979). This increased the independence of the human function from the psychoacoustic data originally used to construct it and encouraged a second assessment of the relations of similar psychoacoustically significant bandwidths to distance and position on the cochlear map. The companion paper (Greenwood, 1991, this issue), found that, among such bandwidths, 'classical' critical bandwidth, and also 'constant interval', estimates in man correspond to equal distances to a closer extent than generally recognized, and over large parts of the frequency range they conform also to an exponential function of distance, as do most of the ERB estimates. This correspondence to almost constant and similar distances facilitates, and forms a part of, an explanation of the operational definitions of critical bandwidth in different experiments. The present account recapitulates the basic explanation of critical bandwidth and consonance offered in Greenwood (1971, 1972b, 1973b, 1974b) and Greenwood et al. (1976): by adding schematic details to the earlier account of critical bandwidth measurements in pure tone masking (the masker-notch interval), two-tone masking, narrow-band masking, and two-tone dissonance-consonance judgements and by outlining its applicability to AM and Quasi-FM detection and to two-band (nominally notched-noise) masking experiments. The measured bandwidths derive from approximately uniform dimensions of traveling wave envelopes in the peak region and from the effects of the resulting spatial pattern of nonlinear interference among primary components. In this account, critical bandwidth in man corresponds to a distance of about 1 or 1.25 mm, depending upon the direction the interval projects from the stimulus frequency to which it is referenced. It is identified with the apical segment of the traveling wave displacement envelope, which in guinea pig and squirrel monkey appears to be about 2/3rds and 3/4ths of a millimeter, respectively and would be about 1.25 mm in man if these distances were scaled (Greenwood, 1962) among these three species (Greenwood, 1974b, 1977a). When reflected also in the basal direction, the upper end of the frequency interval, at a 1.065 mm distance, makes a total two-critical-band distance, which corresponds with the region of nonlinear input-output functions that extends in both directions from the envelope peak and hence also with the frequency-dispersive region of accelerated phase accumulation (Greenwood, 1974b, 1977a).(ABSTRACT TRUNCATED AT 400 WORDS)

  1. Method for effectively maintaining the thickness of mouthguards fabricated using EVA sheets and a circle tray: influence of grooved sheet and heating conditions.

    PubMed

    Takahashi, Mutsumi; Koide, Kaoru; Iwasaki, Shin-Ichi

    2016-06-01

    The shapes of ethylene vinyl acetate (EVA) sheets are mainly square or round. The aim of this study was to elucidate a fabrication method that effectively maintains the thickness of the round sheet. Mouthguards were fabricated using EVA sheets (diameter 125 mm, thickness 4.0 mm) and a vacuum-forming machine. The sheet was pinched at the top and bottom and stabilized by the circle tray. Two heating conditions were compared: (i) the sheet was molded when it sagged 10 mm below the level of the sheet frame at the top of the post under normal conditions (N); and (ii) the sheet frame was lowered to and heated at 50 mm from the level of ordinary use and molded when it sagged 10 mm from the sheet frame (L). Two EVA sheet shapes were compared: an ordinary sheet (O) and a sheet with a horizontal v-shaped groove 30 mm from the anterior end (G). The height of the working model was 20 mm at the incisor point and 15 mm at the first molar. The sheet temperatures of the heating and non-heated surface were measured by the radiation thermometer. Post-molding thickness was determined for the incisal and molar portion. Differences in the thickness were analyzed using two-way anova. The temperature difference among points was smaller under condition L than under condition N. Thickness after formation was higher in condition L than in condition N, and was higher in condition G than in condition O. At the labial surface and the cusp, L-G was thickest. With the present techniques, uneven softening during heating can be improved by lowering the sheet frame and consequently reducing the reduction in the thickness of the sheet. Additionally, the thickness reduction is reduced by creating a horizontal groove on the sheet, establishing the clinical efficacy of this method. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Tamoxifen and Src kinase inhibitors as neuroprotective/neuroregenerative drugs after spinal cord injury

    PubMed Central

    Salgado, Iris K.; Torrado, Aranza I.; Santiago, Jose M.; Miranda, Jorge D.

    2015-01-01

    Spinal cord injury (SCI) is a devastating condition that produces significant changes in the lifestyle of patients. Many molecular and cellular events are triggered after the initial physical impact to the cord. Two major phases have been described in the field of SCI: an acute phase and late phase. Most of the therapeutic strategies are focused on the late phase because this provides an opportunity to target cellular events like apoptosis, demyelination, scar formation and axonal outgrowth. In this mini-review, we will focus on two agents (tamoxifen and a Src kinase family inhibitor known as PP2) that have been shown in our laboratory to produce neuroprotective (increase cell survival) and/or regenerative (axonal outgrowth) actions. The animal model used in our laboratory is adult female rat (~250 g) with a moderate contusion (12.5 mm) to the spinal cord at the T10 level, using the MASCIS impactor device. Tamoxifen or PP2 was administered by implantation of a 15 mg pellet (Innovative Research of America, Sarasota, FL, USA) or by intraperitoneal injections (1.5 mg/kg, every 3 days), respectively, to produce a long-term effect (28 days). Tamoxifen and the Src kinase inhibitor, PP2, are drugs that in rats with a moderate spinal cord injury promote functional locomotor recovery, increase spared white matter tissue, and stimulate axonal outgrowth. Moreover, tamoxifen reduces the formation of reactive oxygen species. Therefore, these drugs are possible therapeutic agents that have a neuroprotective/regenerative activity in vertebrates with SCI. PMID:25878585

  3. Comparison of endoscopic band ligation and endoclip closure of colonic perforation: technical feasibility and efficacy in an ex vivo pig model.

    PubMed

    Lee, Tae Hoon; Han, Joung-Ho; Jung, Yunho; Jung, Yoonho; Lee, Suck-Ho; Kim, Dae Hoon; Shin, Ji Yun; Lee, Tae Soo; Kim, Myunghwan; Choi, Seok-Hwa; Kim, Hyun; Park, Seonmee; Youn, Seijin

    2014-09-01

    Recent reports have indicated several instances of successful treatment of bowel perforation by using endoscopic band ligation (EBL) when treatment with endoclipping is unsuccessful, but this salvage method has not been investigated in any prospective model. Herein we aimed to compare the technical feasibility and efficacy of EBL and endoclip use in intraluminal closure of colon perforation, in an ex vivo model. Standardized colonic perforations were created using fresh porcine colon and subsequently closed by full-thickness interrupted sutures, endoclip (QuickClip2(TM)), or EBL. Each closure site was tested with compressed air by using a digital pressure monitor for evaluating leak pressure. No significant differences were noted between the endoclip and EBL in leak pressures. Mean (± SD) pressures for air leakage from the perforations closed using the different devices were as follows: normal colon samples, 52.0 ± 13.2 mmHg; perforations closed with hand-sewn sutures, 32.3 ± 8.3 mmHg; perforations closed with endoclipping, 53.5 ± 22.7 mmHg; and perforations closed with EBL, 50.4 ± 12.5 mmHg. Time taken for closure by EBL was significantly less than that for closure by endoclipping (3.2 ± 1.7 min vs 6.8 ± 1.3 min, P < 0.01). Further, the number of devices used to achieve complete closure in the EBL group was lower than that with endoclipping (1.6 ± 0.5 vs 3.7 ± 0.8, P < 0.01). Endoluminal closure of a 1.5-cm colon perforation with EBL decreased procedure time and was not inferior in leak pressure compared with endoclipping in this ex vivo porcine model. © 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.

  4. Volume-targeted ventilation and arterial carbon dioxide in neonates.

    PubMed

    Dawson, Catherine; Davies, Mark William

    2005-01-01

    To review the arterial carbon dioxide tensions (PaCO(2)) in newborn infants ventilated using synchronized intermittent mandatory ventilation (SIMV) in volume guarantee mode (using the Dräger Babylog 8000+) with a unit policy targeting tidal volumes of approximately 4 mL/kg. Data on ventilator settings and arterial PaCO(2) levels were collected on all arterial blood gases (ABG; n = 288) from 50 neonates (<33 weeks gestational age) ventilated using the Dräger Babylog 8000+ ventilator (Dräger Medizintechnik GmbH, Lübeck, Germany) in SIMV plus volume guarantee mode. Data were analysed for all blood gases done on the entire cohort in the first 48 h of life and a subanalysis was done on the first gas for each infant (n = 38) ventilated using volume guarantee from admission to the nursery. The number of ABG showing severe hypocapnoea (PaCO(2) < 25 mmHg) and/or severe hypercapnoea (PaCO(2) > 65 mmHg) were determined. The mean (SD) PaCO(2) during the first 48 h was 46.6 (9.0) mmHg. The mean (SD) PaCO(2) on the first blood gas of those infants commenced on volume guarantee from admission was 45.1 (12.5) mmHg. Severe hypo- or hypercapnoea occurred in 8% of infants at the time of their first blood gas measurement, and in <4% of blood gas measurements in the first 48 h. Infants ventilated with volume guarantee ventilation targeting approximately 4 mL/kg (range: 2.9-5.1) have acceptable PaCO(2) levels at the first blood gas measurement and during the first 48 h of life; and avoid severe hypo- or hypercapnoea over 90% of the time.

  5. Excitation-induced force recovery in potassium-inhibited rat soleus muscle

    PubMed Central

    Nielsen, Ole Bækgaard; Hilsted, Linda; Clausen, Torben

    1998-01-01

    Excitation markedly stimulates the Na+-K+ pump in skeletal muscle. The effect of this stimulation on contractility was examined in rat soleus muscles exposed to high extracellular K+ concentration ([K+]o).At a [K+]o of 10 mm, tetanic force declined to 58 % of the force in standard buffer with 5.9 mm K+. Subsequent direct stimulation of the muscle at 1 min intervals with 30 Hz pulse trains of 2 s duration induced a 97 % recovery of force within 14 min. Force recovery could also be elicited by stimulation via the nerve. In muscles exposed to 12.5 mm K+, 30 Hz pulse trains of 2 s duration at 1 min intervals induced a recovery of force from 16 ± 2 to 62 ± 4 % of the initial control force at a [K+]o of 5.9 mm.The recovery of force was associated with a decrease in intracellular Na+ and was blocked by ouabain. This indicates that the force recovery was secondary to activation of the Na+-K+ pump.Excitation stimulates the release of calcitonin gene-related peptide (CGRP) from nerves in the muscle. Since CGRP stimulates the Na+-K+ pump, this may contribute to the excitation-induced force recovery. Indeed, reducing CGRP content by capsaicin pre-treatment or prior denervation prevented both the excitation-induced force recovery and the drop in intracellular Na+.The data suggest that activation of the Na+-K+ pump in contracting muscles counterbalances the depressing effect of reductions in the chemical gradients for Na+ and K+ on excitability. PMID:9769424

  6. Potential renovascular hypertension, space missions, and the role of magnesium

    PubMed Central

    Rowe, William J

    2009-01-01

    Space flight (SF) and dust inhalation in habitats cause hypertension whereas in SF (alone) there is no consistent hypertension but reduced diurnal blood pressure (BP) variation instead. Current pharmaceutical subcutaneous delivery systems are inadequate and there is impairment in the absorption, metabolism, excretion, and deterioration of some pharmaceuticals. Data obtained from the National Aeronautics and Space Administration through the Freedom of Information Act shows that Irwin returned from his 12-day Apollo 15 mission in 1971 and was administered a bicycle stress test. With just three minutes of exercise, his BP was >275/125 mm Hg (heart rate of only 130 beats per minute). There was no acute renal insult. Irwin’s apparent spontaneous remission is suggested to be related to the increase of a protective vasodilator, and his atrial natriuretic peptide (ANP) reduced with SF because of reduced plasma volume. With invariable malabsorption and loss of bone/muscle storage sites, there are significant (P < 0.0001) reductions of magnesium (Mg) required for ANP synthesis and release. Reductions of Mg and ANP can trigger pronounced angiotensin (200%), endothelin, and catecholamine elevations (clearly shown in recent years) and vicious cycles between the latter and Mg deficits. There is proteinuria, elevated creatinine, and reduced renal concentrating ability with the potential for progressive inflammatory and oxidative stress-induced renal disease and hypertension with vicious cycles. After SF, animals show myocardial endothelial injuries and increased vascular resistance of extremities in humans. Even without dust, hypertension might eventually develop from renovascular hypertension during very long missions. Without sufficient endothelial protection from pharmaceuticals, a comprehensive gene research program should begin now. PMID:21694921

  7. Global estimation of effective plant rooting depth: Implications for hydrological modeling

    NASA Astrophysics Data System (ADS)

    Yang, Yuting; Donohue, Randall J.; McVicar, Tim R.

    2016-10-01

    Plant rooting depth (Zr) is a key parameter in hydrological and biogeochemical models, yet the global spatial distribution of Zr is largely unknown due to the difficulties in its direct measurement. Additionally, Zr observations are usually only representative of a single plant or several plants, which can differ greatly from the effective Zr over a modeling unit (e.g., catchment or grid-box). Here, we provide a global parameterization of an analytical Zr model that balances the marginal carbon cost and benefit of deeper roots, and produce a climatological (i.e., 1982-2010 average) global Zr map. To test the Zr estimates, we apply the estimated Zr in a highly transparent hydrological model (i.e., the Budyko-Choudhury-Porporato (BCP) model) to estimate mean annual actual evapotranspiration (E) across the globe. We then compare the estimated E with both water balance-based E observations at 32 major catchments and satellite grid-box retrievals across the globe. Our results show that the BCP model, when implemented with Zr estimated herein, optimally reproduced the spatial pattern of E at both scales (i.e., R2 = 0.94, RMSD = 74 mm yr-1 for catchments, and R2 = 0.90, RMSD = 125 mm yr-1 for grid-boxes) and provides improved model outputs when compared to BCP model results from two already existing global Zr data sets. These results suggest that our Zr estimates can be effectively used in state-of-the-art hydrological models, and potentially biogeochemical models, where the determination of Zr currently largely relies on biome type-based look-up tables.

  8. Novel Approach for Selective Emitter Formation and Front Side Metallization of Crystalline Silicon Solar Cells

    SciTech Connect

    Xu, Baomin

    2010-07-26

    In this project we will explore the possibility of forming the front side metallization and selective emitter layer for the crystalline silicon solar cells through using selective laser ablation to create contact openings on the front surface and a screen printer to make connections with conductive paste. Using this novel approach we expect to reduce the specific contact resistance of the silver gridlines by about one order of magnitude compared to the state-of-art industrial crystalline silicon solar cells to below 1 mΩ∙cm2, and use lightly doped n+ emitter layer with sheet resistance of not smaller than 100 Ω. This represents an enabling improvement on crystalline silicon solar cell performance and can increase the absolute efficiency of the solar cell by about 1%. In this scientific report we first present our result on the selective laser ablation of the nitride layer to make contact openings. Then we report our work on the solar cell fabrication by using the laser ablated contact openings with self-doping paste. Through various electrical property characterization and SIMS analysis, the factors limiting the cell performance have been discussed. While through this proof-of-concept project we could not reach the target on cell efficiency improvement, the process to fabricate 125mm full-sized silicon solar cells using laser ablation and self-doping paste has been developed, and a much better understanding of technical challenges has been achieved. Future direction to realize the potential of the new technology has been clearly defined.

  9. Antioxidant activity via DPPH, gram-positive and gram-negative antimicrobial potential in edible mushrooms.

    PubMed

    Ahmad, Nisar; Mahmood, Fazal; Khalil, Shahid Akbar; Zamir, Roshan; Fazal, Hina; Abbasi, Bilal Haider

    2014-10-01

    Edible mushrooms (EMs) are nutritionally rich source of proteins and essential amino acids. In the present study, the antioxidant activity via 1,1-diphenyl-2-picrylhydrazyl (DPPH) and antimicrobial potential in EMs (Pleurotus ostreatus, Morchella esculenta, P. ostreatus (Black), P. ostreatus (Yellow) and Pleurotus sajor-caju) were investigated. The DPPH radical scavenging activity revealed that the significantly higher activity (66.47%) was observed in Morchella esculenta at a maximum concentration. Similarly, the dose-dependent concentrations (200, 400, 600, 800 and 1000 µg) were also used for other four EMs. Pleurotus ostreatus exhibited 36.13% activity, P. ostreatus (Black (B)) exhibited 30.64%, P. ostreatus (Yellow (Y)) exhibited 40.75% and Pleurotus sajor-caju exhibited 47.39% activity at higher concentrations. Furthermore, the antimicrobial potential were investigated for its toxicity against gram-negative bacterial strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Klebsiella pneumonia, Erwinia carotovora and Agrobacterium tumifaciens), gram-positive bacterial strains (Bacillus subtilis, Bacillus atrophaeus and Staphylococcus aureus) and a fungal strain (Candida albicans) in comparison with standard antibiotics. Antimicrobial screening revealed that the ethanol extract of P. ostreatus was active against all microorganism tested except E. coli. Maximum zone of inhibition (13 mm) was observed against fungus and A. tumifaciens. P. sajor-caju showed best activities (12.5 mm) against B. subtilis, B. atrophaeus and K. pneumonia. P. ostreatus (Y) showed best activities against P. aeroginosa (21.83 mm), B. atrophaeus (20 mm) and C. albicans (21 mm). P. ostreatus (B) exhibited best activities against C. albicans (16 mm) and slightly lower activities against all other microbes except S. typhi. M. esculenta possess maximum activities in terms of inhibition zone against all microorganisms tested except S. typhi.

  10. Treatment of denture-related stomatitis improves endothelial function assessed by flow-mediated vascular dilation.

    PubMed

    Osmenda, Grzegorz; Maciąg, Joanna; Wilk, Grzegorz; Maciąg, Anna; Nowakowski, Daniel; Loster, Jolanta; Dembowska, Elżbieta; Robertson, Douglas; Guzik, Tomasz; Cześnikiewicz-Guzik, Marta

    2017-02-01

    The presence of oral inflammation has recently been linked with the pathogenesis of cardiovascular diseases. While numerous studies have described links between periodontitis and endothelial dysfunction, little is known about the influence of denture-related stomatitis (DRS) on cardiovascular risk. Therefore, the aim of this study was to determine whether the treatment of DRS can lead to improvement of the clinical measures of vascular dysfunction. The DRS patients were treated with a local oral antifungal agent for 3 weeks. Blood pressure, flow-mediated dilatation (FMD) and nitroglycerine-mediated vascular dilatation (NMD) were measured during three study visits: before treatment, one day and two months after conclusion of antifungal therapy. Flow-mediated dilatation measurements showed significant improvement of endothelial function 2 months after treatment (FMD median 5%, 95 CI: 3-8.3 vs. 11%, 95% CI: 8.8-14.4; p < 0.01), while there was no difference in control, endothelium-independent vasorelaxations (NMD; median = 15.3%, 95% CI: 10.8-19.3 vs. 12.7%, 95% CI: 10.6-15; p = 0.3). Other cardiovascular parameters such as systolic (median = 125 mm Hg; 95% CI: 116-129 vs. 120 mm Hg, 95% CI: 116-126; p = 0.1) as well as diastolic blood pressure and heart rate (median = 65.5 bpm, 95% CI: 56.7-77.7 vs. 71 bpm, 95% CI: 66.7-75; p = 0.5) did not change during or after the treatment. Treatment of DRS is associated with improvement of endothelial function. Since endothelial dysfunction is known to precede the development of severe cardiovascular disorders such as atherosclerosis and hypertension, patients should be more carefully screened for DRS in general dental practice, and immediate DRS treatment should be advised.

  11. A numerical study of transcranial focused ultrasound beam propagation at low frequency

    NASA Astrophysics Data System (ADS)

    Yin, Xiangtao; Hynynen, Kullervo

    2005-04-01

    The feasibility of transcranial ultrasound focusing with a non-moving phased array and without skull-specific aberration correction was investigated using computer simulations. Three cadaver skull CT image data sets were incorporated into an acoustic wave transmission model to simulate transskull ultrasound wave propagation. Using a 0.25 MHz hemispherical array (125 mm radius of curvature, 250 mm diameter, 24 255 elements), the simulated beams could be focused and steered with transducer element driving phases and amplitude adjusted for focal beam steering in water (water-path). A total of 82 foci, spanning wide ranges of distance in the three orthogonal dimensions, were simulated to test the focal beam steering capability inside the three skulls. The acoustic pressure distribution in a volume of 20 × 20 × 20 mm3 centred at each focus was calculated with a 0.5 mm spacing in each axis. Clearly defined foci were retained through the skulls (skull-path) in most cases. The skull-path foci were on average 1.6 ± 0.8 mm shifted from their intended locations. The -3 dB skull-path beam width and length were on average 4.3 ± 1.0 mm and 7.7 ± 1.8 mm, respectively. The skull-path sidelobe levels ranged from 25% to 55% of the peak pressure values. The skull-path peak pressure levels were about 10%-40% of their water-path counterparts. Focusing low-frequency beam through skull without skull-specific aberration correction is possible. This method may be useful for applying ultrasound to disrupt the blood-brain barrier for targeted delivery of therapeutic or diagnostic agents, or to induce microbubbles, or for other uses of ultrasound in brain where the required power levels are low and the sharp focusing is not needed.

  12. A numerical study of transcranial focused ultrasound beam propagation at low frequency.

    PubMed

    Yin, Xiangtao; Hynynen, Kullervo

    2005-04-21

    The feasibility of transcranial ultrasound focusing with a non-moving phased array and without skull-specific aberration correction was investigated using computer simulations. Three cadaver skull CT image data sets were incorporated into an acoustic wave transmission model to simulate transskull ultrasound wave propagation. Using a 0.25 MHz hemispherical array (125 mm radius of curvature, 250 mm diameter, 24 255 elements), the simulated beams could be focused and steered with transducer element driving phases and amplitude adjusted for focal beam steering in water (water-path). A total of 82 foci, spanning wide ranges of distance in the three orthogonal dimensions, were simulated to test the focal beam steering capability inside the three skulls. The acoustic pressure distribution in a volume of 20 x 20 x 20 mm(3) centred at each focus was calculated with a 0.5 mm spacing in each axis. Clearly defined foci were retained through the skulls (skull-path) in most cases. The skull-path foci were on average 1.6 +/- 0.8 mm shifted from their intended locations. The -3 dB skull-path beam width and length were on average 4.3 +/- 1.0 mm and 7.7 +/- 1.8 mm, respectively. The skull-path sidelobe levels ranged from 25% to 55% of the peak pressure values. The skull-path peak pressure levels were about 10%-40% of their water-path counterparts. Focusing low-frequency beam through skull without skull-specific aberration correction is possible. This method may be useful for applying ultrasound to disrupt the blood-brain barrier for targeted delivery of therapeutic or diagnostic agents, or to induce microbubbles, or for other uses of ultrasound in brain where the required power levels are low and the sharp focusing is not needed.

  13. Large Auricular Chondrocutaneous Composite Graft for Nasal Alar and Columellar Reconstruction

    PubMed Central

    Kwak, Minho; Yun, Sangho; Yeo, Hyeonjung; Kim, Junhyung; Han, Kihwan

    2012-01-01

    Background Among the various methods for correcting nasal deformity, the composite graft is suitable for the inner and outer reconstruction of the nose in a single stage. In this article, we present our technique for reconstructing the ala and columella using the auricular chondrocutaneous composite graft. Methods From 2004 to 2011, 15 cases of alar and 2 cases of columellar reconstruction employing the chondrocutaneous composite graft were studied, all followed up for 3 to 24 months (average, 13.5 months). All of the patients were reviewed retrospectively for the demographics, graft size, selection of the donor site and outcomes including morbidity and complications. Results The reasons for the deformity were burn scar (n=7), traumatic scar (n=4), smallpox scar (n=4), basal cell carcinoma defect (n=1), and scar contracture (n=1) from implant induced infection. In 5 cases of nostril stricture and 6 cases of alar defect and notching, composite grafts from the helix were used (8.9×12.5 mm). In 4 cases of retracted ala, grafts from the posterior surface of the concha were matched (5×15 mm). For the reconstruction of the columella, we harvested the graft from the posterior scapha (9×13.5 mm). Except one case with partial necrosis and delayed healing due to smoking, the grafts were successful in all of the cases and there was no deformity of the donor site. Conclusions An alar and columellar defect can be reconstructed successfully with a relatively large composite graft without donor site morbidity. The selection of the donor site should be individualized according to the 3-dimensional configuration of the defect. PMID:22872834

  14. Transition of carbon nanostructures in heptane diffusion flames

    NASA Astrophysics Data System (ADS)

    Hu, Wei-Chieh; Hou, Shuhn-Shyurng; Lin, Ta-Hui

    2017-02-01

    The flame synthesis has high potential in industrial production of carbon nanostructure (CNS). Unfortunately, the complexity of combustion chemistry leads to less controlling of synthesized products. In order to improve the understanding of the relation between flames and CNSs synthesized within, experiments were conducted through heptane flames in a stagnation-point liquid-pool system. The operating parameters for the synthesis include oxygen supply, sampling position, and sampling time. Two kinds of nanostructures were observed, carbon nanotube (CNT) and carbon nano-onion (CNO). CNTs were synthesized in a weaker flame near extinction. CNOs were synthesized in a more sooty flame. The average diameter of CNTs formed at oxygen concentration of 15% was in the range of 20-30 nm. For oxygen concentration of 17%, the average diameter of CNTs ranged from 24 to 27 nm, while that of CNOs was around 28 nm. For oxygen concentration of 19%, the average diameter of CNOs produced at the sampling position 0.5 mm below the flame front was about 57 nm, while the average diameters of CNOs formed at the sampling positions 1-2.5 mm below the flame front were in the range of 20-25 nm. A transition from CNT to CNO was observed by variation of sampling position in a flame. We found that the morphology of CNS is directly affected by the presence of soot layer due to the carbonaceous environment and the growth mechanisms of CNT and CNO. The sampling time can alter the yield of CNSs depending on the temperature of sampling position, but the morphology of products is not affected.

  15. Comparison of obesity, overweight and elevated blood pressure in children attending public and private primary schools in Benin City, Nigeria.

    PubMed

    Sadoh, W E; Israel-Aina, Y T; Sadoh, A E; Uduebor, J E; Shaibu, M; Ogonor, E; Enugwuna, F C

    2017-07-01

    Overweight and obesity in children, and adolescents is on the rise globally. Affected children are prone to cardio-metabolic problems later in life, especially hypertension. The prevalence of obesity/overweight may differ depending on school type. Private schools are attended mostly by children of the affluent, while public schools are attended predominantly by those in the low and middle socio-economic classes. To compare the prevalence of overweight, obesity and elevated blood pressure (BP) in pupils attending public and private primary schools in an urban community in Nigeria. In this cross sectional study, the BMI and BP of pupils in public and private primary schools, recruited by multistage sampling method, were measured. Their nutritional status was categorized using their BMI percentiles. Analysis was by SPSS. A total of 1466 pupils were recruited, 814(55.5%) were in public schools and 722(49.2%) were males. The prevalence of overweight and obesity was higher in private schools 11.8% and 11.7% compared to public schools 3.3% and 0.9%. The mean systolic BP of pupils in public schools 96.8 ± 12.5 mmHg was higher than that in private schools 95.5 ± 10.2 mmHg, p = 0.032. Distribution of pupils with prehypertension and hypertension between private and public schools was not significantly different. The prevalence of overweight and obesity is higher in pupils attending private schools compared to those in public school. Urgent measures are needed to stem this tide through education, weight reduction and physical activity programs, especially in pupils attending private schools.

  16. Linear dimensional stability of elastomeric impression materials over time.

    PubMed

    Garrofé, Analía B; Ferrari, Beatriz A; Picca, Mariana; Kaplan, Andrea E

    2011-01-01

    The purpose of this study was to evaluate the linear dimensional stability of different elastomeric impression materials over time. A metal mold was designed with its custom trays, which were made of thermoplastic sheets (Sabilex sheets 0.125 mm thick). Three impressions were taken of it with each of the following: the polyvinylsiloxane Examix-GC-(AdEx), Aquasil-Dentsply-(AdAq) and Panasil-Kettenbach-(AdPa), and the polydimethylsiloxane Densell-Dental Medrano-(CoDe), Speedex-Coltene-(CoSp) and Lastic-Kettenbach-(CoLa). All impressions were taken with putty and light-body materials using a one-step technique. Standardized digital photographs were taken at different time intervals (0, 15, 30, 60, 120 minutes; 24 hours; 7 and 14 days), using an "ad-hoc" device, and analyzed using software (Image Tool) by measuring the distance between lines previously made at the top of the mold. The results were analyzed by ANOVA for repeated measures. The initial and final values for mean and SD were: AdEx: 1.32 (0.01) and 1.31 (0.00); AdAq: 1.32 (0.00) and 1.32 (0.00), AdPa: 1.327 (0.006) and 1.31 (0.00); CoDe: 1.32 (0.00) and 1.32 (0.01); CoSp: 1.327 (0.006) and 1.31 (0.00), CoLa: 1.327 (0.006) and 1.303 (0.006). Statistical evaluation showed that both material and time have significant effects. Under the conditions in this study we conclude that time would significantly affect the lineal dimensional stability of elastomeric impression materials.

  17. Johann Spectrometer for High Resolution X-ray Spectroscopy

    NASA Astrophysics Data System (ADS)

    Machek, Pavel; Welter, Edmund; Caliebe, Wolfgang; Brüggmann, Ulf; Dräger, Günter; Fröba, Michael

    2007-01-01

    A newly designed vacuum Johann spectrometer with a large focusing analyzer crystal for inelastic x-ray scattering and high resolution fluorescence spectroscopy has been installed at the DORIS III storage ring. Spherically bent crystals with a maximum diameter of 125 mm, and cylindrically bent crystals are employed as dispersive optical elements. Standard radius of curvature of the crystals is 1000 mm, however, the design of the mechanical components also facilitates measurements with smaller and larger bending radii. Up to four crystals are mounted on a revolving crystal changer which enables crystal changes without breaking the vacuum. The spectrometer works at fixed Bragg angle. It is preferably designed for the measurements in non-scanning mode with a broad beam spot, and offers a large flexibility to set the sample to the optimum position inside the Rowland circle. A deep depletion CCD camera is employed as a position sensitive detector to collect the energy-analyzed photons on the circumference of the Rowland circle. The vacuum in the spectrometer tank is typically 10-6 mbar. The sample chamber is separated from the tank either by 25 μm thick Kapton windows, which allows samples to be measured under ambient conditions, or by two gate valves. The spectrometer is currently installed at wiggler beamline W1 whose working range is 4-10.5 keV with typical flux at the sample of 5×1010photons/s/mm2. The capabilities of the spectrometer are illustrated by resonant inelastic experiments on 3d transition metals and rare earth compounds, and by chemical shift measurements on chromium compounds.

  18. Optimization of typical diffuse herbicide pollution control by soil amendment configurations under four levels of rainfall intensities.

    PubMed

    Ouyang, Wei; Huang, Weijia; Wei, Peng; Hao, Fanghua; Yu, Yongyong

    2016-06-15

    Herbicides are a main source of agricultural diffuse pollution due to their wide application in tillage practices. The aim of this study is to optimize the control efficiency of the herbicide atrazine with the aid of modified soil amendments. The soil amendments were composed of a combination of biochar and gravel. The biochar was created from corn straw with a catalytic pyrolysis of ammonium dihydrogen phosphate. The leaching experiments under four rainfall conditions were measured for the following designs: raw soil, soil amended with gravel, biochar individually and together with gravel. The control efficiency of each design was also identified. With the designed equipment, the atrazine content in the contaminant load layer, gravel substrate layer, biochar amendment layer and soil layer was measured under four types of rainfall intensities (1.25 mm/h, 2.50 mm/h, 5.00 mm/h and 10.00 mm/h). Furthermore, the vertical distribution of atrazine in the soil sections was also monitored. The results showed that the herbicide leaching load increased under the highest rainfall intensity in all designs. The soil with the combination of gravel and biochar provided the highest control efficiency of 87.85% on atrazine when the additional proportion of biochar was 3.0%. The performance assessment under the four kinds of rainfall intensity conditions provided the guideline for the soil amendment configuration. The combination of gravel and biochar is recommended as an efficient method for controlling diffuse herbicide pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Final test results for the Schott HCE on a LS-2 collector.

    SciTech Connect

    Moss, Timothy A.; Brosseau, Douglas A.

    2005-07-01

    Sandia National Laboratories has completed thermal performance testing on the Schott parabolic trough receiver using the LS-2 collector on the Sandia rotating platform at the National Solar Thermal Test Facility in Albuquerque, NM. This testing was funded as part of the US DOE Sun-Lab USA-Trough program. The receiver tested was a new Schott receiver, known as Heat Collector Elements (HCEs). Schott is a new manufacturer of trough HCEs. The Schott HCEs are 4m long; therefore, two were joined and mounted on the LS-2 collector module for the test. The Schott HCE design consists of a 70mm diameter high solar absorptance coated stainless steel (SS) tube encapsulated within a 125mm diameter Pyrex{reg_sign} glass tube with vacuum in the annulus formed between the SS and glass tube to minimize convection heat losses. The Schott HCE design is unique in two regards. First, the bellows used to compensate for the difference in thermal expansion between the metal and glass tube are inside the glass envelope rather than outside. Second, the composition of materials at the glass-to-metal seal has very similar thermal expansion coefficients making the joint less prone to breakage from thermal shock. Sandia National Laboratories provided both the azimuth and elevation collector module tracking systems used during the tests. The test results showed the efficiency of the Schott HCE to be very similar to current HCEs being manufactured by Solel. This testing provided performance verification for the use of Schott tubes with Solargenix trough collector assemblies at currently planned trough power plant projects in Arizona and Nevada.

  20. Flooding after fire: Impacts of the 2013 Colorado Front Range floods on the High Park Fire burn scar

    NASA Astrophysics Data System (ADS)

    Kampf, S. K.; Schmeer, S.; MacDonald, L. H.; Brogan, D. J.; Nelson, P. A.

    2014-12-01

    In June 2012, the High Park Fire west of Fort Collins, CO burned 350 km2 of steep forested terrain, leading to elevated runoff and erosion in watersheds draining the burned area. Under the auspices of a NSF RAPID grant we began monitoring precipitation, hillslope-scale sediment production, stream stage, and channel geomorphic change in Skin Gulch and Hill Gulch, two 15 km2 watersheds within the High Park Fire. Short-duration summer thunderstorms are typically the dominant cause of post-fire runoff and erosion in the central and southern Rocky Mountains, but in September 2013 an extreme, long duration storm dropped more than 200 mm of rain in 48 hours. This storm provided a unique opportunity to compare the hydrologic and geomorphic effects of smaller summer thunderstorms to those of the long duration, high magnitude September event. Mean June-August 2013 precipitation in these watersheds was 125 mm, less than half the total for the September 2013 event, but this summer precipitation led to a mean sediment yield of 8 Mg ha-1, about double the mean sediment yield of the much larger September storm. Hillslope sediment production was highest during summer storms that were shorter duration but had higher 5-15 minute precipitation intensities than the September storm. These localized summer 2013 storms led to flashy pulses of flow in the channel network that caused relatively small amounts of channel aggradation or incision. In contrast, the September 2013 event produced sustained high flows that led to substantial geomorphic change throughout the channel network, with more than 2 m of aggradation at the outlet of Skin Gulch. These results indicate that the high intensity summer thunderstorms were most effective at mobilizing sediment from hillslopes, but the more spatially uniform rainfall during the September event produced much more dramatic downstream channel geomorphic change.

  1. Optical spectroscopy with a near-single-mode fiber-feed and adaptive optics

    NASA Astrophysics Data System (ADS)

    Ge, Jian; Angel, J. Roger P.; Shelton, J. Christopher

    1998-07-01

    We report on first astronomical results with a cross-dispersed optical echelle spectrograph fed by a near single-mode fiber. We also present on a novel design of a new adaptive optics (AO) optimized fiber-fed cross-dispersed echelle spectrograph. The spectrograph is designed to match with AO corrected images in the optical bands provided by such as the Mt. Wilson 100 inch, Starfire Optical Range 3.5 m AO telescopes. Ultimately, it will be installed at the 6.5 m MMT, when this has high resolution AO correcting the optical spectrum. The spectrograph, fed by a 10 micron fused silica fiber, is unique in that the entire spectrum from 0.4 micron to 1.0 micron will be almost completely covered at resolution 200,000 in one exposure. The detector is a 2k X 4k AR coated back illuminated CCD with 15 micron pixel size. The close order spacing allowed by the sharp AO image makes the full cover possible. A 250 X 125 mm(superscript 2) Milton Roy R2 echelle grating with 23.2 grooves mm(superscript -1) and a blaze angle of 63.5 deg provides main dispersion. A double pass BK7 prism with 21 deg wedge angle provides cross dispersion, covering the spectrum from order 193 to 77. The spectrograph is used in the quasi- Littrow configuration with an off-axis Maksutov collimator/camera. The fiber feeds the AO corrected beams from the telescope Cassegrain focus to the spectrograph, which is set up on an optical bench. The spectrograph will be used mainly to study line profiles of solar type stars, to explore problems of indirect detection of planets and also study interstellar medium, circumstellar medium and metal abundance and isotopic ratios of extremely metal-poor stars.

  2. Hot water swallows improve symptoms and accelerate esophageal clearance in esophageal motility disorders.

    PubMed

    Triadafilopoulos, G; Tsang, H P; Segall, G M

    1998-06-01

    Cold liquid ingestion may precipitate episodes of dysphagia and chest pain in patients with spastic esophageal motility disorders. The effect of hot liquids on esophageal symptoms, esophageal peristalsis, and clearance and any potential therapeutic benefit in such patients has not been examined. Using esophageal scintigraphy and manometry, we have investigated the effects of hot water swallows on dysphagia, chest pain, and esophageal motility and clearance in patients with esophageal motility disorders. We studied 48 men and women with intermittent dysphagia to both solids and liquids, chest pain, and/or regurgitation. All patients underwent upper endoscopy, barium swallow, and esophageal manometry using standard techniques. Esophageal scintigraphy assessed esophageal transit time (ETT) and retrograde intraesophageal movement of bolus at baseline (22 degrees C) and after hot (60 degrees C) water swallows. Esophageal manometry assessed the amplitude and duration of esophageal contractions in response to baseline and hot water swallows. Patients were followed clinically for as long as 6 months to assess symptomatic response. We found that baseline esophageal scintigraphy revealed a mean ETT of 48.5 seconds; after hot water swallow, mean ETT was 27.8 seconds (p < 0.001). The number of secondary peaks at baseline was 3.5; after hot water swallow, it was 2.1 (p < 0.001). Baseline esophageal manometry showed a mean esophageal body contraction amplitude of 188 mm Hg (mean duration, 11.8 seconds) in response to wet swallows and 125 mm Hg (mean duration, 5.7 seconds) with hot water swallows (p < 0.001). Clinically, 28 (58%) of 48 patients noted significant (>50%) improvement of their symptoms and have been ingesting hot water or other hot liquids regularly with their meals. We conclude that hot water accelerates esophageal clearance, decreases the amplitude and duration of esophageal body contractions, and improves symptoms in patients with esophageal motility disorders

  3. Strain rate effects on the mechanical behavior of two Dual Phase steels in tension

    NASA Astrophysics Data System (ADS)

    Cadoni, E.; Singh, N. K.; Forni, D.; Singha, M. K.; Gupta, N. K.

    2016-05-01

    This paper presents an experimental investigation on the strain rate sensitivity of Dual Phase steel 1200 (DP1200) and Dual Phase steel 1400 (DP1400) under uni-axial tensile loads in the strain rate range from 0.001 s-1 to 600 s-1. These materials are advanced high strength steels (AHSS) having high strength, high capacity to dissipate crash energy and high formability. Flat sheet specimens of the materials having gauge length 10 mm, width 4 mm and thickness 2 mm (DP1200) and 1.25 mm (DP1400), are tested at room temperature (20∘C) on electromechanical universal testing machine to obtain their stress-strain relation under quasi-static condition (0.001 s-1), and on Hydro-Pneumatic machine and modified Hopkinson bar to study their mechanical behavior at medium (3 s-1, and 18 s-1) and high strain rates (200 s-1, 400 s-1, and 600 s-1) respectively. Tests under quasi-static condition are performed at high temperature (200∘C) also, and found that tensile flow stress is a increasing function of temperature. The stress-strain data has been analysed to determine the material parameters of the Cowper-Symonds and the Johnson-Cook models. A simple modification of the Johnson-Cook model has been proposed in order to obtain a better fit of tests at high temperatures. Finally, the fractographs of the broken specimens are taken by scanning electron microscope (SEM) to understand the fracture mechanism of these advanced high strength steels at different strain rates.

  4. ALMA OBSERVATIONS OF THE DEBRIS DISK AROUND THE YOUNG SOLAR ANALOG HD 107146

    SciTech Connect

    Ricci, L.; Carpenter, J. M.; Fu, B.; Hughes, A. M.; Corder, S.; Isella, A.

    2015-01-10

    We present the Atacama Large Millimeter/submillimeter Array (ALMA) continuum observations at a wavelength of 1.25 mm of the debris disk surrounding the ∼100 Myr old solar analog HD 107146. The continuum emission extends from about 30 to 150 AU from the central star with a decrease in the surface brightness at intermediate radii. We analyze the ALMA interferometric visibilities using debris disk models with radial profiles for the dust surface density parameterized as (1) a single power law, (2) a single power law with a gap, and (3) a double power law. We find that models with a gap of radial width ∼8 AU at a distance of ∼80 AU from the central star, as well as double power-law models with a dip in the dust surface density at ∼70 AU provide significantly better fits to the ALMA data than single power-law models. We discuss possible scenarios for the origin of the HD 107146 debris disk using models of planetesimal belts in which the formation of Pluto-sized objects trigger disruptive collisions of large bodies, as well as models that consider the interaction of a planetary system with a planetesimal belt and spatial variation of the dust opacity across the disk. If future observations with higher angular resolution and sensitivity confirm the fully depleted gap structure discussed here, a planet with a mass of approximately a few Earth masses in a nearly circular orbit at ∼80 AU from the central star would be a possible explanation for the presence of the gap.

  5. A Point-of-Care Immunosensor for Human Chorionic Gonadotropin in Clinical Urine Samples Using a Cuneated Polysilicon Nanogap Lab-on-Chip

    PubMed Central

    Balakrishnan, S. R.; Hashim, U.; Gopinath, Subash C. B.; Poopalan, P.; Ramayya, H. R.; Iqbal Omar, M.; Haarindraprasad, R.; Veeradasan, P.

    2015-01-01

    Human chorionic gonadotropin (hCG), a glycoprotein hormone secreted from the placenta, is a key molecule that indicates pregnancy. Here, we have designed a cost-effective, label-free, in situ point-of-care (POC) immunosensor to estimate hCG using a cuneated 25 nm polysilicon nanogap electrode. A tiny chip with the dimensions of 20.5 × 12.5 mm was fabricated using conventional lithography and size expansion techniques. Furthermore, the sensing surface was functionalized by (3-aminopropyl)triethoxysilane and quantitatively measured the variations in hCG levels from clinically obtained human urine samples. The dielectric properties of the present sensor are shown with a capacitance above 40 nF for samples from pregnant women; it was lower with samples from non-pregnant women. Furthermore, it has been proven that our sensor has a wide linear range of detection, as a sensitivity of 835.88 μA mIU-1 ml-2 cm-2 was attained, and the detection limit was 0.28 mIU/ml (27.78 pg/ml). The dissociation constant Kd of the specific antigen binding to the anti-hCG was calculated as 2.23 ± 0.66 mIU, and the maximum number of binding sites per antigen was Bmax = 22.54 ± 1.46 mIU. The sensing system shown here, with a narrow nanogap, is suitable for high-throughput POC diagnosis, and a single injection can obtain triplicate data or parallel analyses of different targets. PMID:26368287

  6. A Point-of-Care Immunosensor for Human Chorionic Gonadotropin in Clinical Urine Samples Using a Cuneated Polysilicon Nanogap Lab-on-Chip.

    PubMed

    Balakrishnan, S R; Hashim, U; Gopinath, Subash C B; Poopalan, P; Ramayya, H R; Iqbal Omar, M; Haarindraprasad, R; Veeradasan, P

    2015-01-01

    Human chorionic gonadotropin (hCG), a glycoprotein hormone secreted from the placenta, is a key molecule that indicates pregnancy. Here, we have designed a cost-effective, label-free, in situ point-of-care (POC) immunosensor to estimate hCG using a cuneated 25 nm polysilicon nanogap electrode. A tiny chip with the dimensions of 20.5 × 12.5 mm was fabricated using conventional lithography and size expansion techniques. Furthermore, the sensing surface was functionalized by (3-aminopropyl)triethoxysilane and quantitatively measured the variations in hCG levels from clinically obtained human urine samples. The dielectric properties of the present sensor are shown with a capacitance above 40 nF for samples from pregnant women; it was lower with samples from non-pregnant women. Furthermore, it has been proven that our sensor has a wide linear range of detection, as a sensitivity of 835.88 μA mIU(-1) ml(-2) cm(-2) was attained, and the detection limit was 0.28 mIU/ml (27.78 pg/ml). The dissociation constant Kd of the specific antigen binding to the anti-hCG was calculated as 2.23 ± 0.66 mIU, and the maximum number of binding sites per antigen was Bmax = 22.54 ± 1.46 mIU. The sensing system shown here, with a narrow nanogap, is suitable for high-throughput POC diagnosis, and a single injection can obtain triplicate data or parallel analyses of different targets.

  7. Osteomalacia: The Missing Link in the Pathogenesis of Bisphosphonate-Related Osteonecrosis of the Jaws?

    PubMed Central

    Saia, Giorgia; Bettini, Giordana; Tronchet, Anita; Totola, Andrea; Bedogni, Giorgio; Tregnago, Paolo; Valenti, Maria Teresa; Bertoldo, Francesco; Ferronato, Giuseppe; Nocini, Pier Francesco; Blandamura, Stella; Dalle Carbonare, Luca

    2012-01-01

    Background. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a well-documented adverse event from treatment with nitrogen-containing bisphosphonates (NBPs). During a preliminary histomorphometric study aimed at assessing the rate of bone remodeling in the jaws of patients with surgically resected BRONJ, we found a defect of bone mineralization (unpublished data). We hypothesized that osteomalacia could be a risk factor for BRONJ in patients taking NBPs. Therefore, we looked for static and dynamic histomorphometric evidence of osteomalacia in biopsies from subjects with and without BRONJ. Methods. This case-control study used histomorphometric analysis of bone specimens of patients using NBPs (22 patients with BRONJ and 21 patients without BRONJ) who required oral surgical interventions for the treatment/prevention of osteonecrosis. Patients were given tetracycline hydrochloride according to a standardized protocol before taking bone biopsies from their jaws. Biopsies with evidence of osteomyelitis or necrosis at histology were excluded from the study. Osteomalacia was defined as a mineralization lag time >100 days, a corrected mean osteoid thickness >12.5 mm, and an osteoid volume >10%. Results. In all, 77% of patients with BRONJ were osteomalacic compared with 5% of patients without BRONJ, according to histomorphometry. Because osteomalacia was found almost exclusively in NBP users with BRONJ, this is likely to be a generalized process in which the use of NBPs further deteriorates mechanisms of bone repair. Conclusions. Osteomalacia represents a new and previously unreported risk factor for disease development. This finding may contribute to a better understanding of the pathogenesis of this disease and help with the development of strategies to increase the safety of NBP administration. PMID:22723507

  8. Nigerian Population Research on Environment, Gene and Health (NIPREGH) – objectives and protocol

    PubMed Central

    Odili, Augustine N.; Ogedengbe, John O.; Nwegbu, Maxwell; Anumah, Felicia O.; Asala, Samuel; Staessen, Jan A

    2014-01-01

    Abstract Sub-Saharan Africa is currently undergoing an epidemiological transition from a disease burden largely attributable to communicable diseases to that resulting from a combination of both communicable and chronic non-communicable diseases. Data on chronic disease incidence, lifestyle, environmental and genetic risk factors are sparse in this region. This report aimed at providing relevant information in respect to risk factors that increase blood pressure and lead to development of intermediate cardiovascular phenotypes. We presented the rationale, objectives and key methodological features of the Nigerian Population Research on Environment, Gene and Health (NIPREGH) study. The challenges encountered in carrying out population study in this part of the world and the approaches at surmounting them were also presented. The preliminary data as at 20 November 2013 showed that out of the 205 individuals invited starting from early April 2013, 160 (72 women) consented and were enrolled; giving a response rate of 78%. Participants' age ranged from 18 to 80 years, with a mean (SD) of 39.8 (12.4) years and they were of 34 different ethnic groups spread over 24 states out of the 36 states that constitute Nigeria. The mean (SD) of office and home blood pressures were 113.0 (15.2) mm Hg systolic, 73.5 (12.5) mm Hg diastolic and 117.3 (15.0) mm Hg systolic, and 76.0 (9.6) mm Hg diastolic, respectively. Forty-three (26.8%) participants were hypertensive and 8 (5.0%) were diabetic. In addition to having the unique potential of recruiting a cohort that is a true representative of the entire Nigerian population, NIPREGH is feasible and the objectives realisable. PMID:25332707

  9. Exploring {sup 57}Co as a new isotope for brachytherapy applications

    SciTech Connect

    Enger, Shirin A.; Lundqvist, Hans; D'Amours, Michel; Beaulieu, Luc

    2012-05-15

    Purpose: The characteristics of the radionuclide {sup 57}Co make it interesting for use as a brachytherapy source. {sup 57}Co combines a possible high specific activity with the emission of relatively low-energy photons and a half-life (272 days) suitable for regular source exchanges in an afterloader. {sup 57}Co decays by electron capture to the stable {sup 57}Fe with emission of 136 and 122 keV photons. Methods: A hypothetical {sup 57}Co source based on the Flexisource brachytherapy encapsulation with the active core set as a pure cobalt cylinder (length 3.5 mm and diameter 0.6 mm) covered with a cylindrical stainless-steel capsule (length 5 mm and thickness 0.125 mm) was simulated using Geant4 Monte Carlo (MC) code version 9.4. The radial dose function, g(r), and anisotropy function F(r,{theta}), for the line source approximation were calculated following the TG-43U1 formalism. The results were compared to well-known {sup 192}Ir and {sup 125}I radionuclides, representing the higher and the lower energy end of brachytherapy, respectively. Results: The mean energy of photons in water, after passing through the core and the encapsulation material was 123 keV. This hypothetical {sup 57}Co source has an increasing g(r) due to multiple scatter of low-energy photons, which results in a more uniform dose distribution than {sup 192}Ir. Conclusions: {sup 57}Co has many advantages compared to {sup 192}Ir due to its low-energy gamma emissions without any electron contamination. {sup 57}Co has an increasing g(r) that results in a more uniform dose distribution than {sup 192}Ir due to its multiple scattered photons. The anisotropy of the {sup 57}Co source is comparable to that of {sup 192}Ir. Furthermore, {sup 57}Co has lower shielding requirements than {sup 192}Ir.

  10. Two-dimensional optoacoustic tomography: transducer array and image reconstruction algorithm

    NASA Astrophysics Data System (ADS)

    Oraevsky, Alexander A.; Andreev, Valeri A.; Karabutov, Alexander A.; Esenaliev, Rinat O.

    1999-06-01

    Opto-acoustic tomography (OAT) utilizes laser pulses to create acoustic sources in tissue and wide-band detection of pressure profiles for the image reconstruction. A new laser optoacoustic imaging system (LOIS) for breast cancer detection and two-dimensional visualization is described. A Q-switched Nd:YAG laser was used for generation of opto-acoustic profiles in phantoms and tissues in vitro. Acoustic pulses were detected by a 12 element linear array of piezoelectric transducers. Each transducer was made of 0.5-mm thick PVDF slabs with dimensions of 4.3 mm X 12.5 mm. Signal-to-noise ratio was calculated and the sensitivity of optoacoustic system was evaluated. The axial (in-depth) resolution and the lateral resolution of the system were determined. The axial resolution of the receiving array was limited by its frequency band and was estimated to be approximately 1 mm. The lateral resolution was about 2.5 times the lateral dimension of the 'tumor' and defined by the finite aperture of the array and relatively large size of the single transducer. The time of full data acquisition was limited by the time allowed in clinical procedure of about 5 - 10 minutes. The procedure of signal processing is described. It includes high-pass signal filtering, compensation for acoustic diffraction, detection of the irradiated surface position and rejection of the reverberating signal. Radial back-projection algorithm for image reconstruction was developed and included in the computer code. Two-dimensional opto-acoustic images of simulated spheres and objects inside tissue phantoms are presented. The contrast of these images and limits of detection and localization of deeply embedded tumors are discussed.

  11. High-resolution 3-D T1*-mapping and quantitative image analysis of GRAY ZONE in chronic fibrosis.

    PubMed

    Pop, Mihaela; Ramanan, Venkat; Yang, Franklin; Zhang, Li; Newbigging, Susan; Ghugre, Nilesh R; Wright, Graham A

    2014-12-01

    The substrate of potentially lethal cardiac arrhythmias often resides in the gray zone (GZ), a mixture of viable myocytes and collagen strands found between healthy myocardium and infarct core (IC). The specific aims of this paper are to demonstrate correspondence between regions delineated in T1* (apparent T1) maps and tissue characteristics seen in histopathology and to determine the MR imaging resolution needed to adequately identify GZ-associated substrate in chronic infarct. For this, a novel 3-D multicontrast late enhancement (MCLE) MR method was used to image ex vivo swine hearts with chronic infarction, at high resolution ( 0.6×0.6×1.25 mm). Pixel-wise classified tissue maps were calculated using steady-state and T1* images as input to a fuzzy-clustering algorithm. Quantitative histology based on collagen stains was performed in n = 10 selected slabs and showed very good correlations between histologically-determined areas of heterogeneous and dense fibrosis, and the corresponding GZ ( R2 = 0.96) and IC ( R2 = 0.97 ) in tissue classified maps. Furthermore, in n = 24 slabs, we performed volumetric measurements of GZ and IC, at the original and decreased image resolutions. Our results demonstrated that the IC volume remained relatively unchanged across all resolutions, whereas the GZ volume progressively increased with diminished image resolution, with changes reaching significance at 1×1×5 mm resolution (p < 0.05 ) but not at 1×1×2.5 mm, suggesting that this resolution may be sufficient to adequately identify the GZ from MCLE images, enabling an effective MR probing of remodeled myocardium in late infarct. Future work will focus on translating these findings to optimizing the current in vivo MCLE imaging of the GZ.

  12. Effects of short-term heated water-based exercise training on systemic blood pressure in patients with resistant hypertension: a pilot study.

    PubMed

    Guimarães, Guilherme V; Cruz, Lais G B; Tavares, Aline C; Dorea, Egidio L; Fernandes-Silva, Miguel M; Bocchi, Edimar A

    2013-12-01

    High blood pressure (BP) increases the risk of cardiovascular diseases, and its control is a clinical challenge. Regular exercise lowers BP in patients with mild-to-moderate hypertension. No data are available on the effects of heated water-based exercise in hypertensive patients. Our objective was to evaluate the effects of heated water-based exercise on BP in patients with resistant hypertension. We tested the effects of 60-min heated water-based exercise training three times per week in 16 patients with resistant hypertension (age 55±6 years). The protocol included walking and callisthenic exercises. All patients underwent 24-h ambulatory blood pressure monitoring (ABPM) before and after a 2-week exercise program in a heated pool. Systolic office BP was reduced from 162 to 144 mmHg (P<0.004) after heated-water training. After the heated-water exercise training during 24-h ABPM, systolic BP decreased from 135 to 123 mmHg (P=0.02), diastolic BP decreased from 83 to 74 mmHg (P=0.001), daytime systolic BP decreased from 141 to 125 mmHg (P=0.02), diastolic BP decreased from 87 to 77 mmHg (P=0.009), night-time systolic BP decreased from 128 to 118 mmHg (P=0.06), and diastolic BP decreased from 77 to 69 mmHg (P=0.01). In addition, BP cardiovascular load was reduced significantly during the 24-h daytime and night-time period after the heated water-based exercise. Heated water-based exercise reduced office BP and 24-h daytime and night-time ABPM levels. These effects suggest that heated water-based exercise may have a potential as a new therapeutic approach to resistant hypertensive patients.

  13. Exploring intra- and inter-reader variability in uni-dimensional, bi-dimensional, and volumetric measurements of solid tumors on CT scans reconstructed at different slice intervals.

    PubMed

    Zhao, Binsheng; Tan, Yongqiang; Bell, Daniel J; Marley, Sarah E; Guo, Pingzhen; Mann, Helen; Scott, Marietta L J; Schwartz, Lawrence H; Ghiorghiu, Dana C

    2013-06-01

    Understanding magnitudes of variability when measuring tumor size may be valuable in improving detection of tumor change and thus evaluating tumor response to therapy in clinical trials and care. Our study explored intra- and inter-reader variability of tumor uni-dimensional (1D), bi-dimensional (2D), and volumetric (VOL) measurements using manual and computer-aided methods (CAM) on CT scans reconstructed at different slice intervals. Raw CT data from 30 patients enrolled in oncology clinical trials was reconstructed at 5, 2.5, and 1.25 mm slice intervals. 118 lesions in the lungs, liver, and lymph nodes were analyzed. For each lesion, two independent radiologists manually and, separately, using computer software, measured the maximum diameter (1D), maximum perpendicular diameter, and volume (CAM only). One of them blindly repeated the measurements. Intra- and inter-reader variability for the manual method and CAM were analyzed using linear mixed-effects models and Bland-Altman method. For the three slice intervals, the maximum coefficients of variation for manual intra-/inter-reader variability were 6.9%/9.0% (1D) and 12.3%/18.0% (2D), and for CAM were 5.4%/9.3% (1D), 11.3%/18.8% (2D) and 9.3%/18.0% (VOL). Maximal 95% reference ranges for the percentage difference in intra-reader measurements for manual 1D and 2D, and CAM VOL were (-15.5%, 25.8%), (-27.1%, 51.6%), and (-22.3%, 33.6%), respectively. Variability in measuring the diameter and volume of solid tumors, manually and by CAM, is affected by CT slice interval. The 2.5mm slice interval provides the least measurement variability. Among the three techniques, 2D has the greatest measurement variability compared to 1D and 3D. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. [Auriculo temporal nerve. Neuroanatomic bases of the Frey's syndrome].

    PubMed

    Decuadro-Sáenz, G; Castro, G; Sorrenti, N; Doassans, I; Deleon, S; Salle, F; Saibene, A; Santamaría, A; Pérez-Brignani, A; Soria-Vargas, V R

    2008-06-01

    The aim of this study was to precise the relationships of the auriculotemporal nerve in the infratemporal and parotid regions. We realized micro-dissections of thirty-two infratemporal and parotid regions of human cadaver's formol-fixed. The pattern of origin was: one root: 15.4%, two roots: 73.1%, three roots: 11.5%. In all cases, the lateral root present the major diameter (2-2.5 mm). In those cases with two roots, these formed a neural loop round the middle meningeal artery in the 89.4% of the cases. The origin of the medial root was the posterior border of the inferior alveolar nerve. The median distance between the lateral root and the temporomandibular joint capsule was 1.5 mm, with asymmetric pattern: right: 2 mm (rank: 0-7 mm; ED: 1.90 mm); left: 1.25 mm (rank: 0-3 mm; ED: 0.88 mm). In 10 cases (31.3%) the lateral root was in direct contact with the articular capsule, with asymmetric pattern: left: 46.1%; right: 21%. The median distance between the superior aspect of the articular disk and the trunk of the auriculotemporal nerve in the posterior aspect of the temporomandibular joint was 10,5 mm (ED: 4.06 mm), with asymmetric pattern: right: 9 mm (rank: 5-18.0 mm; ED: 3.70 mm); left: 11.0 mm (rank: 3.0-20 mm; ED: 4.41 mm). We discussed the rol of this findings in the etiology of the Frey's syndrome.

  15. Characterization of Graded MASCIS Contusion Spinal Cord Injury using Somatosensory Evoked Potentials

    PubMed Central

    Agrawal, Gracee; Kerr, Candace; Thakor, Nitish V.; All, Angelo H.

    2009-01-01

    Study Design Electrophysiological analysis using somatosensory evoked potentials (SEPs) and behavioral assessment using Basso-Beattie-Bresnahan (BBB) scale were compared over time for graded MASCIS contusion spinal cord injury (SCI). Objective To study SEP responses across different contusion injury severities and to compare them with BBB scores. Summary of Background Data For any SCI therapy evaluation, it is important to accurately and objectively standardize the injury model. The graded MASCIS contusion injuries on dorsal spine have been standardized using BBB, which is subjective and prone to human errors. Furthermore, dorsal pathway disruption does not always produce locomotor deficits. SEP monitoring provides an advantage of providing a reliable and objective assessment of the functional integrity of dorsal sensory pathways. Methods Four groups of Fischer rats received contusion at T8 using NYU-MASCIS impactor from impact heights of 6.25 (mild), 12.5 (moderate), 25 (severe), or 50 mm (very severe). The control group underwent laminectomy only. SEP and BBB recordings were performed once prior to injury, and then weekly for up to 7 weeks. Results Graded levels of injury produced concomitant attenuations in hindlimb SEP amplitudes. Following injury, 25 and 50 mm groups together differed significantly from 12.5 and 6.25 mm groups (p<0.01). From week 5, differences between 12.5 and 6.25 mm groups also became apparent (p<0.01), which showed significant electrophysiological improvement. However, no significant differences were observed between 25 and 50 mm groups, which showed negligible electrophysiological recovery. While comparable differences between different groups were also detected by BBB after injury (p<0.001), BBB was less sensitive in detecting any improvement in 6.25 and 12.5 mm groups. Conclusion SEP amplitudes and BBB scores decrease corresponding to increase in injury severity, however these show different temporal patterns of recovery. These results demonstrate the utility of SEPs, in conjunction with BBB, to monitor therapeutic interventions in SCI research. PMID:20354478

  16. Different systolic blood pressure targets for people with history of stroke or transient ischaemic attack: PAST-BP (Prevention After Stroke—Blood Pressure) randomised controlled trial

    PubMed Central

    McManus, Richard J; Roalfe, Andrea; Fletcher, Kate; Taylor, Clare J; Martin, Una; Virdee, Satnam; Greenfield, Sheila; Hobbs, F D Richard

    2016-01-01

    Objective To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. Design Open label randomised controlled trial. Setting 99 general practices in England, with participants recruited in 2009-11. Participants People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. Interventions Intensive systolic blood pressure target (<130 mm Hg or 10 mm Hg reduction from baseline if this was <140 mm Hg) or standard target (<140 mm Hg). Apart from the different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. Main outcome measure Change in systolic blood pressure between baseline and 12 months. Results 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). Conclusions Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a <140 mm Hg target led to a clinically important reduction in blood pressure. Trial registration Current Controlled Trials ISRCTN29062286. PMID:26919870

  17. Effects of Heat Treatment on the Ballistic Impact Properties of Inconel 718 for Jet Engine Fan Containment Applications

    NASA Technical Reports Server (NTRS)

    Pereira, J. Michael; Lerch, Bradley A.

    2001-01-01

    The effects of heat treating Inconel 718 on the ballistic impact response and failure mechanisms were studied. Two different annealing conditions and an aged condition were considered. Large differences in the static properties were found between the annealed and the aged material, with the annealed condition having lower strength and hardness and greater elongation than the aged. High strain rate tests show similar results. Correspondingly large differences were found in the velocity required to penetrate material in the two conditions in impact tests involving 12.5 mm diameter, 25.4 mm long cylindrical Ti-6-4 projectiles impacting flat plates at velocities in the range of 150 to 300 m/sec. The annealed material was able to absorb over 25 percent more energy than the aged. This is contrary to results observed for ballistic impact response for higher velocity impacts typically encountered in military applications where it has been shown that there exists a correlation between target hardness and ballistic impact strength. Metallographic examination of impacted plates showed strong indication of failure due to adiabatic shear. In both materials localized bands of large shear deformation were apparent, and microhardness measurements indicated an increase in hardness in these bands compared to the surrounding material. These bands were more localized in the aged material than in the annealed material. In addition the annealed material underwent significantly greater overall deformation before failure. The results indicate that lower elongation and reduced strain hardening behavior lead to a transition from shear to adiabatic shear failure, while high elongation and better strain hardening capabilities reduce the tendency for shear to localize and result in an unstable adiabatic shear failure. This supports empirical containment design methods that relate containment thickness to the static toughness.

  18. [Experimental principles of the V.A.C.-therapy -- pressure values in superficial soft tissue and the applied foam].

    PubMed

    Willy, C; von Thun-Hohenstein, H; von Lübken, F; Weymouth, M; Kossmann, T; Engelhardt, M

    2006-04-01

    Measurement of the pressure during V.A.C.(R)-therapy in superficial parts of the affected soft tissue as well as at the soft tissue/foam-interface, measurement of pressure values along bigger distances in the foam and the comparison of pressure transfer between polyurethane and polyvinyl-alcohol foams. A multi-channel electronic transducer-tipped catheter system based on the piezo-resistant principle was used. Measurement was performed on a plain table surface, at a bovine muscle as well as in human tibial anterior muscle of a patient after fasciotomy. Applied pressure values by V.A.C.(R)-therapy-units were 50 to 200 mm Hg (continuous suction modus). 100 % pressure transition through vacuum-therapy-foams to wound surface, almost 100 % pressure transition even along 60 cm in very large polyurethane-foams using only one trac-pad connector. Pressure values > 125 mm Hg using polyvinyl-alcohol-foams showed a reduction of up to 25 % in distances > 15 cm from trac-pad-connector. On the surface of the affected soft tissue there are negative and positive pressure values (25 % quartile: - 25 mm Hg; 75 % quartile: + 15 mm Hg). Pore walls of the foam can produce positive pressure conditions resulting in soft tissue compression and consecutively hypoperfusion or ischemia. V.A.C.(R)-therapy seems to produce an heterogeneity of pressure distribution at the wound ground leading to pressure gradients and facilitating drainage of interstitial fluid. This mechanism could explain the anti-edema effects of V.A.C.(R)-therapy resulting indirectly in an increased nutritive perfusion.

  19. Optoacoustic tomography of breast cancer with arc-array transducer

    NASA Astrophysics Data System (ADS)

    Andreev, Valeri G.; Karabutov, Alexander A.; Solomatin, Sergey V.; Savateeva, Elena V.; Aleinikov, Vadim; Zhulina, Yulia V.; Fleming, R. Declan; Oraevsky, Alexander A.

    2000-05-01

    The second generation of the laser optoacoustic imaging system for breast cancer detection, localization and characterization using a 32-element arc-shaped transducer array was developed and tested. Each acoustic transducer was made of 110-micrometers thick SOLEF PVDF film with dimensions of 1mm X 12.5mm. The frequency band of transducer array provided 0.4-mm axial in-depth resolution. Cylindrical shape of this 10-cm long transducer array provided an improved lateral resolution of 1.0 mm. Original and compact design of low noise preamplifiers and wide band amplifiers was employed. The system sensitivity was optimized by choosing limited bandwidth of ultrasonic detection 20-kHz to 2-MHz. Signal processing was significantly improved and optimized resulting in reduced data collection time of 13 sec. The computer code for digital signal processing employed auto- gain control, high-pass filtering and denoising. An automatic recognition of the opto-acoustic signal detected from the irradiated surface was implemented in order to visualize the breast surface and improve the accuracy of tumor locations. Radial back-projection algorithm was used for image reconstruction. Optimal filtering of image was employed to reduce low and high frequency noise. The advantages and limitations of various contrast-enhancing filters applied to the entire image matrix were studied and discussed. Time necessary for image reconstruction was reduced to 32 sec. The system performance was evaluated initially via acquisition of 2D opto-acoustic images of small absorbing spheres in breast-tissue-like phantoms. Clinical ex-vivo studies of mastectomy specimen were also performed and compared with x-ray radiography and ultrasound.

  20. Significant decrease of subcutaneous body fat during tube-weaning from enteral feeding.

    PubMed

    Kaimbacher, Petra S; Wallner-Liebmann, Sandra J; Dunitz-Scheer, Marguerite; Zwi Scheer, Peter J; Cvirn, Gerhard; Schrabmair, Walter; Greilberger, Joachin; Schnedl, Wolfang J; Tafeit, Erwin

    2016-02-01

    The aim of this paper was to evaluate anthropometry and subcutaneous body fat on long-term enterally-fed children during tube weaning through a prospective cohort study with a pre-post-test design. The LIPOMETER, an optical device, was used to measure the thickness of subcutaneous adipose tissue (SAT) layers (in mm). The specification of 15 evenly-distributed body sites allows for a precise measurement of subcutaneous body fat distribution, known as subcutaneous adipose tissue topography (SAT-Top). Anthropometry and SAT-Top were determined in long-term enterally fed children in the pre- and post-tube weaning phase of a 3-week tube weaning program. The results of the SAT-Top measurements are presented on three levels: 15 body sites, four body regions and SAT-total. The sample size consisted of 30 long-term tube-fed children (13 girls and 17 boys). Both sexes demonstrated a clear decrease of anthropometry and subcutaneous body fat during tube weaning. Girls lost -26.1 mm, -30.7%, (P=0.002) of their initial fat mass and boys -12.5 mm, -18.4%, (P<0.001). In general, girls had thicker SAT layers in all SAT-Top measurements and a higher reduction of subcutaneous body fat during the intervention. At the end of the tube weaning program girls and boys demonstrated similar results of subcutaneous body fat on the three observed levels: 15 body sites, four body regions and SAT-total. Upon discharge, total subcutaneous body fat of girls and boys was 58.9 mm and 55.5 mm, respectively. This study presents a basic documentation of changes in anthropometry and subcutaneous body fat during tube weaning and could potentially be used to help create guidelines for safe tube weaning.

  1. Volume assessment accuracy in computed tomography: a phantom study

    PubMed Central

    Prionas, Nicolas D.; Ray, Shonket; Boone, John M.

    2011-01-01

    There is a broad push in the cancer imaging community to eventually replace linear tumor measurements with three-dimensional evaluation of tumor volume. To evaluate the potential accuracy of volume measurement in tumors by CT, a gelatin phantom consisting of 55 polymethylmethacrylate (PMMA) spheres spanning diameters from 1.6 mm to 25.4 mm was fabricated and scanned using thin slice (0.625 mm) CT (GE LightSpeed 16). Nine different reconstruction combinations of field of view dimension (FOV = 20, 30, 40 cm) and CT kernel (standard, lung, bone) were analyzed. Contiguous thin-slice images were averaged to produce CT images with greater thicknesses (1.25, 2.50, 5.0 mm). Simple grayscale thresholding techniques were used to segment the PMMA spheres from the gelatin background, where a total of 1800 spherical volumes were evaluated across the permutations studied. The geometric simplicity of the phantom established upper limits on measurement accuracy. In general, smaller slice thickness and larger sphere diameters produced more accurate volume assessment than larger slice thickness and smaller sphere diameter. The measured volumes were smaller than the actual volumes by a common factor depending on slice thickness; overall, 0625 mm slices produced on average 18%, 1.25 mm slices produced 22%, 2.5 mm CT slices produced 29%, and 5.0 mm slices produced 39% underestimates of volume (mm3). Field of view did not have a significant effect on volume accuracy. Reconstruction algorithm significantly affected volume accuracy (p < 0.0001), with the lung kernel having the smallest error, followed by the bone and standard kernels. The results of this investigation provide guidance for CT protocol development and may guide the development of more advanced techniques to promote quantitatively accurate CT volumetric analysis of tumors. PMID:20592693

  2. Clinical accuracy of ExacTrac intracranial frameless stereotactic system

    SciTech Connect

    Ackerly, T.; Lancaster, C. M.; Geso, M.; Roxby, K. J.

    2011-09-15

    Purpose: In this paper, the authors assess the accuracy of the Brainlab ExacTrac system for frameless intracranial stereotactic treatments in clinical practice. Methods: They recorded couch angle and image fusion results (comprising lateral, longitudinal, and vertical shifts, and rotation corrections about these axes) for 109 stereotactic radiosurgery and 166 stereotactic radiotherapy patient treatments. Frameless stereotactic treatments involve iterative 6D image fusion corrections applied until the results conform to customizable pass criteria, theirs being 0.7 mm and 0.5 deg. for each axis. The planning CT slice thickness was 1.25 mm. It has been reported in the literature that the CT slices' thickness impacts the accuracy of localization to bony anatomy. The principle of invariance with respect to patient orientation was used to determine spatial accuracy. Results: The data for radiosurgery comprised 927 image pairs, of which 532 passed (pass ratio of 57.4%). The data for radiotherapy comprised 15983 image pairs, of which 10 050 passed (pass ratio of 62.9%). For stereotactic radiotherapy, the combined uncertainty of ExacTrac calibration, image fusion, and intrafraction motion was (95% confidence interval) 0.290-0.302 and 0.306-0.319 mm in the longitudinal and lateral axes, respectively. The combined uncertainty of image fusion and intrafraction motion in the anterior-posterior coordinates was 0.174-0.182 mm. For stereotactic radiosurgery, the equivalent ranges are 0.323-0.393, 0.337-0.409, and 0.231-0.281 mm. The overall spatial accuracy was 1.24 mm for stereotactic radiotherapy (SRT) and 1.35 mm for stereotactic radiosurgery (SRS). Conclusions: The ExacTrac intracranial frameless stereotactic system spatial accuracy is adequate for clinical practice, and with the same pass criteria, SRT is more accurate than SRS. They now use frameless stereotaxy exclusively at their center.

  3. Reducing the Use of Pesticides with Site-Specific Application: The Chemical Control of Rhizoctonia solani as a Case of Study for the Management of Soil-Borne Diseases.

    PubMed

    Le Cointe, Ronan; Simon, Thomas E; Delarue, Patrick; Hervé, Maxime; Leclerc, Melen; Poggi, Sylvain

    Reducing our reliance on pesticides is an essential step towards the sustainability of agricultural production. One approach involves the rational use of pesticides combined with innovative crop management. Most control strategies currently focus on the temporal aspect of epidemics, e.g. determining the optimal date for spraying, regardless of the spatial mechanics and ecology of disease spread. Designing innovative pest management strategies incorporating the spatial aspect of epidemics involves thorough knowledge on how disease control affects the life-history traits of the pathogen. In this study, using Rhizoctonia solani/Raphanus sativus as an example of a soil-borne pathosystem, we investigated the effects of a chemical control currently used by growers, Monceren® L, on key epidemiological components (saprotrophic spread and infectivity). We tested the potential "shield effect" of Monceren® L on pathogenic spread in a site-specific application context, i.e. the efficiency of this chemical to contain the spread of the fungus from an infected host when application is spatially localized, in our case, a strip placed between the infected host and a recipient bait. Our results showed that Monceren® L mainly inhibits the saprotrophic spread of the fungus in soil and may prevent the fungus from reaching its host plant. However, perhaps surprisingly we did not detect any significant effect of the fungicide on the pathogen infectivity. Finally, highly localized application of the fungicide-a narrow strip of soil (12.5 mm wide) sprayed with Monceren® L-significantly decreased local transmission of the pathogen, suggesting lowered risk of occurrence of invasive epidemics. Our results highlight that detailed knowledge on epidemiological processes could contribute to the design of innovative management strategies based on precision agriculture tools to improve the efficacy of disease control and reduce pesticide use.

  4. Accuracy Assessment of Immediate and Delayed Implant Placements Using CAD/CAM Surgical Guides.

    PubMed

    Alzoubi, Fawaz; Massoomi, Nima; Nattestad, Anders

    2016-10-01

    The aim of this study is to assess the accuracy of immediately placed implants using Anatomage Invivo5 computer-assisted design/computer-assisted manufacturing (CAD/CAM) surgical guides and compare the accuracy to delayed implant placement protocol. Patients who had implants placed using Anatomage Invivo5 CAD/CAM surgical guides during the period of 2012-2015 were evaluated retrospectively. Patients who received immediate implant placements and/or delayed implant placements replacing 1-2 teeth were included in this study. Pre- and postsurgical images were superimposed to evaluate deviations at the crest, apex, and angle. A total of 40 implants placed in 29 patients were included in this study. The overall mean deviations measured at the crest, apex, and angle were 0.86 mm, 1.25 mm, and 3.79°, respectively. The means for the immediate group deviations were: crest = 0.85 mm, apex = 1.10, and angle = 3.49°. The means for the delayed group deviations were: crest = 0.88 mm, apex = 1.59, and angle = 4.29°. No statistically significant difference was found at the crest and angle; however, there was a statistically significant difference between the immediate and delayed group at the apex, with the immediate group presenting more accurate placements at the apical point than the delayed group. CAD/CAM surgical guides can be reliable tools to accurately place implants immediately and/or in a delayed fashion. No statistically significant differences were found between the delayed and the immediate group at the crest and angle, however apical position was more accurate in the immediate group.

  5. Conversion Equation between the Drop Height in the New York University Impactor and the Impact Force in the Infinite Horizon Impactor in the Contusion Spinal Cord Injury Model.

    PubMed

    Khuyagbaatar, Batbayar; Kim, Kyungsoo; Kim, Yoon Hyuk

    2015-12-15

    There are several widely used devices for controlled contusion of the spinal cord, including the Ohio State University device, the University of British Columbia multi-mechanisms injury device, the New York University (NYU) impactor, and the Infinite Horizon (IH) impactor. Although various devices and protocols have been used to generate consistent injury severities, further investigation of the relationship between the key parameters of different spinal cord injury (SCI) contusion devices (e.g., drop height in the NYU impactor and impact force in the IH impactor) will improve our understanding of SCI mechanisms. A three-dimensional finite element model of the rat spinal cord from T9 to T10 that included the white and gray matters, dura mater, and cerebrospinal fluid was developed to investigate the von-Mises stress, maximum principal strain, and maximum displacement of the spinal cord for the drop height in the NYU impactor and the impact force in the IH impactor. A quantitative relationship was established as a conversion equation between two key parameters--i.e., the drop height and the impact force--in the NYU and IH impactors from regression equations for peak von-Mises stress, peak maximum principal strain, and maximum displacement in the spinal cord with respect to drop height and impact force with very high coefficients of determination. The consistent correlation was represented as a simple equation (Force = (28.2 ± 3.2) · Height((0.83 ± 0.07))) under the experimental conditions of a 10-g rod in the NYU impactor and an impact velocity of 125 mm/sec in the IH impactor. Thus, the key biomechanical parameter for a contusion device can be converted or translated to that of another device to analyze experimental results from multiple contusion devices.

  6. The kinematics and kinetics of pedestrians on a laterally swaying footbridge

    NASA Astrophysics Data System (ADS)

    Claff, D.; Williams, M. S.; Blakeborough, A.

    2017-10-01

    Progress in understanding human-structure interaction (HSI) on footbridges has been hampered by the shortage of quality data collected in realistic environments. This paper reports a novel experiment conducted on a naturally-swaying 7 m footbridge of frequency 0.67 Hz and amplitudes up to 125 mm. Subjects crossed the bridge while wearing infrared motion-tracking markers and pressure-sensing insoles. The bridge was fitted with bespoke force plates, allowing investigators to simultaneously record kinematic and kinetic reactions to the structure's motion, which was assumed simple harmonic. The bridge was naturally excited by the test subjects, who were allowed to walk at a comfortable self-chosen pace. The data show that the subjects adopted a fixed-in-space Centre of Mass (CoM) strategy but their Centres of Pressure (CoP) were highly correlated to the position of the bridge deck within its lateral oscillation cycle (henceforth 'bridge phase'), allowing for the prediction of wide and crossed steps. Ground forces generally correlated to CoM-CoP separation, which reflected the phase of the bridge at the previous heel-strike. Instantaneous step width was correlated to the bridge phase and is proportional to the offset in the Medial-Lateral (M-L) ground force between consecutive steps. The Inverted Pendulum Model (IPM) was evaluated using the data, exhibiting a limited fit to the recorded ground forces. Finally, the pedestrian-induced work on the bridge and system stability boundaries are also calculated, revealing mechanisms for bridge instability to occur.

  7. A compact L-band Ortho Mode Junction

    NASA Astrophysics Data System (ADS)

    Pisanu, T.; Marongiu, P.; Navarrini, A.; Valente, G.

    2010-07-01

    We describe the design construction and performance of a L-band (1300-1800 MHz) Ortho Mode Junction for the L-P dual-band receiver to be installed on the 64 m Sardinia Radio Telescope (SRT), a new radio telescope which is being built in Sardinia, Italy. The Ortho Mode Junction (OMJ) separates two orthogonal linearly polarized signals propagating in a 172 mm diameter circular waveguide and couple them into four coaxial outputs. The OMJ is part of an OMT (Ortho Mode Transducer), which includes two 1800 hybrids allowing to recombine the out-of-phase signals from the balanced OMJ outputs. The OMJ consists of four probes arranged in symmetrical configuration across the circular waveguide. A shaped tuning stub with cylindrical profile is placed a quarter wavelength away from the probes to guarantee broadband operation with low reflection coefficient across L-band. The four identical probes have a cylindrical structure, each consisting of three concentric cylinders that attach to the central pin of standard 50 Ω 7/16-type coaxial connectors. The OMJ will be cooled at 80 K inside a compact dewar together with directional couplers and Low Noise Amplifiers. The two linearly polarized signals from an input 190 mm diameter room temperature L-band feed couple into the cryogenic dewar through a vacuum window located across the waveguide. Inside the dewar, the 190 mm diameter circular waveguide is tapered down to 172 mm using a conical transition (length 85 mm) filled with a Styrodur® foam that provides mechanical support for a 0.125 mm thick Kapton vacuum barrier. A 0.6 mm air gap across the 172 mm circular waveguide provides thermal decoupling between the ambient temperature and the 80 K OMJ, which is connected to the conical transition output.

  8. Effects of Heat Treatment on the Ballistic Impact Properties of Inconel 718 for Jet Engine Fan Containment Applications

    NASA Technical Reports Server (NTRS)

    Pereira, J. Michael; Lerch, Bradley A.

    1999-01-01

    The effects of heat treating Inconel 718 on the ballistic impact response and failure mechanisms were studied. Two different annealing conditions and an aged condition were considered. Large differences in the static properties were found between the annealed and the aged material, with the annealed condition having lower strength and hardness and greater elongation than the aged. High strain rate tests show similar results. Correspondingly large differences were found in the velocity required to penetrate material in the two conditions in impact tests involving 12.5 mm diameter, 25.4 mm long cylindrical Ti-6-4 projectiles impacting flat plates at velocities in the range of 150 to 300 m/sec. The annealed material was able to absorb over 25 percent more energy than the aged. This is contrary to results observed for ballistic impact response for higher velocity impacts typically encountered in military applications where it has been shown that there exists a correlation between target hardness and ballistic impact strength. Metallographic examination of impacted plates showed strong indication of failure due to adiabatic shear. In both materials localized bands of large shear deformation were apparent, and microhardness measurements indicated an increase in hardness in these bands compared to the surrounding material. These bands were more localized in the aged material than in the annealed material. In addition the annealed material underwent significantly greater overall deformation before failure. The results indicate that lower elongation and reduced strain hardening behavior lead to a transition from shear to adiabatic shear failure, while high elongation and better strain hardening capabilities reduce the tendency for shear to localize and result in an unstable adiabatic shear failure. This supports empirical containment design methods that relate containment thickness to the static toughness.

  9. Effects of Heat Treatment on the Ballistic Impact Properties of Inconel 718 for Jet Engine Fan Containment Applications

    NASA Technical Reports Server (NTRS)

    Pereira, J. Michael; Lerch, Bradley A.

    2000-01-01

    The effects of heat treating Inconel 718 on the ballistic impact response and failure mechanisms were studied. Two different annealing conditions and an aged condition were considered. Large differences in the static properties were found between the annealed and the aged material, with the annealed condition having lower strength and hardness and greater elongation than the aged. Correspondingly large differences were found in the velocity required to penetrate material in the two conditions in impact tests involving 12.5 mm diameter, 25.4 mm long cylindrical Ti-6-4 projectiles impacting flat plates at velocities in the range of 150 to 300 m/sec. The annealed material was able to absorb over 25 percent more energy than the aged. This is contrary to results observed for ballistic impact response for higher velocity impacts typically encountered in military applications where it has been shown that there exists a correlation between target hardness and ballistic impact strength. Metallographic examination of impacted plates showed strong indication of failure due to adiabatic shear. In both materials localized bands of large shear deformation were apparent, and microhardness measurements indicated an increase in hardness in these bands compared to the surrounding material. These bands were more localized in the aged material than in the annealed material. In addition the annealed material underwent significantly greater overall deformation before failure. The results indicate that high elongation and better strain hardening capabilities reduce the tendency for shear to localize and result in an unstable adiabatic shear failure. This supports empirical containment design methods that relate containment thickness to the static toughness.

  10. SHERLOC: Scanning Habitable Environments With Raman & Luminescence for Organics & Chemicals, an Investigation for 2020

    NASA Astrophysics Data System (ADS)

    Beegle, L. W.; Bhartia, R.; DeFlores, L. P.; Asher, S. A.; Burton, A. S.; Clegg, S. M.; Conrad, P. G.; Edgett, K. S.; Ehlmann, B. L.; Langenhorst, F.; Fries, M.; Nealson, K. H.; Popp, J.; Sobron, P.; Steele, A.; Wiens, R. C.; Williford, K. H.

    2014-12-01

    The Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals SHERLOC investigation was recently selected for the Mars 2020 integrated payload. SHERLOC enables non-contact, spatially resolved, and highly sensitivity detection and characterization of organics and minerals in the Martian surface and near subsurface. SHERLOC is an arm-mounted, Deep UV (DUV) resonance Raman and fluorescence spectrometer utilizing a 248.6-nm DUV laser and 50 micron spot size. The laser is integrated to an autofocusing/scanning optical system, and co-boresighted to a context imager with a spatial resolution of 30 μm. SHERLOC operates over a 7 × 7 mm area through use of an internal scanning mirror. The 500 micron depth of view in conjunction with the MAHLI heritage autofocus mechanisms enables arm placements from 48 ±12.5 mm above natural or abraded surfaces without the need for rover arm repositioning/movement. Additionally, borehole interiors to a depth of ~25 mm, at angles from normal incidence to ±20 degrees, can be analyzed. Deep UV induced native fluorescence is very sensitive to condensed carbon and aromatic organics, enabling detection at or below 10-6 w/w (1 ppm) at <100 µm spatial scales. SHERLOC's deep UV resonance Raman enables detection and classification of aromatic and aliphatic organics with sensitivities of 10-2 to below 10-4 w/w at <50 µm spatial scales. In addition to organics, the deep UV Raman enables detection and classification of minerals relevant to aqueous chemistry with grain sizes below 20 µm grains. The instrument goals are to assess past aqueous history, detect the presence and preservation of potential biosignatures, and to support selection of return samples. To do this, SHERLOC will measure CHNOPS-containing mineralogy, measure the distribution and type of organics preserved at the surface, and correlate them to textural features.

  11. Right ventricular ejection efficiency: a new echocardiographic measure of mechanical performance in chronic pulmonary hypertension.

    PubMed

    López-Candales, Angel; Lopez, Francisco R; Trivedi, Setu; Elwing, Jean

    2014-04-01

    The severity of pulmonary vascular resistance (PVR) is known to be a critical determinant of right ventricular (RV) systolic function; this relationship remains poorly characterized. We therefore, designed a study to examine the relationship that exists between echocardiographically measured PVR and maximal tricuspid annular plane systolic excursion (TAPSE) to gain some insight regarding RV ejection efficiency (RVEe) in patients with chronic pulmonary hypertension (cPH). Standard echocardiographic measures of RV size and systolic performance were recorded from 95 patients (age 54 ± 15 years and pulmonary artery systolic pressures [PASP] that range from 20 to 125 mmHg). For this study, RVEe was defined as TAPSE/Echocardiographic PVR. A strong negative correlation (R(2) = -0.51, P < 0.001) was seen between TAPSE and PASP; however, a power curve trend line fit the relationship between RVEe and PASP (R(2) = 0.77; P < 0.01). In a multiple regression analysis, abnormal pulmonary pressures were better identified when RVEe (P < 0.0001) was used. Based on these results, it appears that measurement of RVEe might be extremely useful for the assessment of RV mechanics and plasticity. The power curve relationship clearly demonstrates that minimal changes in PASP (up to 50 mmHg) result in dramatic reductions in RVEe. A steady decline in RVEe, though at a lower rate, continues to occur with increasing PASP. Additional studies are required using RVEe into a functional RV imaging algorithm and determine if RVEe correlates with development of symptoms, response to therapy and overall clinical outcomes. © 2013, Wiley Periodicals, Inc.

  12. SU-E-T-481: Dosimetric Effects of Tissue Heterogeneity in Proton Therapy: Monte Carlo Simulation and Experimental Study Using Animal Tissue Phantoms.

    PubMed

    Liu, Y; Zheng, Y

    2012-06-01

    Accurate determination of proton dosimetric effect for tissue heterogeneity is critical in proton therapy. Proton beams have finite range and consequently tissue heterogeneity plays a more critical role in proton therapy. The purpose of this study is to investigate the tissue heterogeneity effect in proton dosimetry based on anatomical-based Monte Carlo simulation using animal tissues. Animal tissues including a pig head and beef bulk were used in this study. Both pig head and beef were scanned using a GE CT scanner with 1.25 mm slice thickness. A treatment plan was created, using the CMS XiO treatment planning system (TPS) with a single proton spread-out-Bragg-peak beam (SOBP). Radiochromic films were placed at the distal falloff region. Image guidance was used to align the phantom before proton beams were delivered according to the treatment plan. The same two CT sets were converted to Monte Carlo simulation model. The Monte Carlo simulated dose calculations with/without tissue omposition were compared to TPS calculations and measurements. Based on the preliminary comparison, at the center of SOBP plane, the Monte Carlo simulation dose without tissue composition agreed generally well with TPS calculation. In the distal falloff region, the dose difference was large, and about 2 mm isodose line shift was observed with the consideration of tissue composition. The detailed comparison of dose distributions between Monte Carlo simulation, TPS calculations and measurements is underway. Accurate proton dose calculations are challenging in proton treatment planning for heterogeneous tissues. Tissue heterogeneity and tissue composition may lead to isodose line shifts up to a few millimeters in the distal falloff region. By simulating detailed particle transport and energy deposition, Monte Carlo simulations provide a verification method in proton dose calculation where inhomogeneous tissues are present. © 2012 American Association of Physicists in Medicine.

  13. Effects of compression on the loss of newly synthesized proteoglycans and proteins from cartilage explants

    SciTech Connect

    Sah, R.L.; Doong, J.Y.; Grodzinsky, A.J.; Plaas, A.H.; Sandy, J.D. )

    1991-04-01

    The effects of mechanical compression of calf cartilage explants on the catabolism and loss into the medium of proteoglycans and proteins radiolabeled with (35S)sulfate and (3H)proline were examined. A single 2- or 12-h compression of 3-mm diameter cartilage disks from a thickness of 1.25 to 0.50 mm, or slow cyclic compression (2 h on/2 h off) from 1.25 mm to 1.00, 0.75, or 0.50 mm for 24 h led to transient alterations and/or sustained increases in loss of radiolabeled macromolecules. The effects of imposing or removing loads were consistent with several compression-induced physical mediators including fluid flow, diffusion, and matrix disruption. Cyclic compression induced convective fluid flow and enhanced the loss of 35S- and 3H-labeled macromolecules from tissue into medium. In contrast, prolonged static compression induced matrix consolidation and appeared to hinder the diffusional transport and loss of 35S- and 3H-labeled macromolecules. Since high amplitude cyclic compression led to a sustained increase in the rate of loss of 3H- and 35S-labeled macromolecules that was accompanied by an increase in the rate of loss of (3H)hydroxyproline residues and an increase in tissue hydration, such compression may have caused disruption of the collagen meshwork. The 35S-labeled proteoglycans lost during such cyclic compression were of smaller average size than those from controls, but contained a similarly low proportion (approximately 15%) that could form aggregates with excess hyaluronate and link protein. The size distribution and aggregability of the remaining tissue proteoglycans and 35S-labeled proteoglycans were not markedly affected. The loss of tissue proteoglycan paralleled the loss of 35S-labeled macromolecules.

  14. Wear performance of monolithic dental ceramics with different surface treatments.

    PubMed

    Preis, Verena; Weiser, Felix; Handel, Gerhard; Rosentritt, Martin

    2013-05-01

    To investigate the two-body wear performance of monolithic dental ceramics with different surface treatments. Standardized specimens (n = 8/ series) were fabricated from three monolithic dental ceramics (experimental translucent zirconia, experimental shaded zirconia, lithium disilicate). Four groups of each material were defined according to clinically relevant surface treatments: polished, polishedground, polished-ground-repolished, glazed. Two-body wear tests with steatite antagonists were performed in a chewing simulator. Surface roughness (R(a)) was controlled, and wear depths of specimens and antagonistic wear areas were calculated in relation to human enamel as reference. Statistical analysis of wear data was carried out using one-way ANOVA and Bonferroni multiple comparison test for post hoc analysis (α = .05). Scanning electron microscopy was applied for evaluating wear performance of ceramics and antagonists. Polished, ground, and repolished zirconia showed no wear, while glaze was abraded. Irrespective of the surface treatment, wear depth of lithium disilicate was significantly (P

  15. Thermal control modeling approach for GRAPE (GRAntecan PolarimEter)

    NASA Astrophysics Data System (ADS)

    Di Varano, I.; Woche, M.; Strassmeier, K. G.

    2016-08-01

    GRAPE is the polarimeter planned to be installed on the main Cassegrain focus of GTC (Gran Telescopio Canarias), having an equivalent entrance pupil of 10.4 m, located at the Observatorio del Roque de los Muchachos (ORM) , in La Palma, Canary Islands. It's meant to deliver full Stokes (IQUV) polarimetry covering the spectral range 0.420-1.6 μ, in order to feed the HORS instrument (High Optical Resolution Spectrograph), mounted on the Nasmyth platform, which has a FWHM resolving power of about 25,000 (5 pixel) designed for the wavelength range of 380-800 nm. Two calcite blocks and a BK-7 prism arranged in a Foster configuration are splitting the Ø12.5mm collimated beam into the ordinary and extraordinary components. The entire subunit from the Foster prisms down to the input fibers is rotated by steps of 45 degrees in order to retrieve Q, U components. By inserting a quarter wave retarder plate before the entrance to the Foster unit circular polarization is measured too. The current paper consist of two main parts: at first CFD simulations are introduced, which have been run compliant to the specifications derived by the environmental conditions and the transient thermal gradients taking into account the presence of the electronic cabinets installed, which are triggering the boundary conditions for the outer structure of the instrument; then a thermal control model is proposed based on heat exchangers to stabilize the inner temperature when compensation via passive insulation is not enough. The tools that have been adopted to reach for such goal are Ansys Multiphysics, in particular CFX package and Python scripts.

  16. Can Blood Pressure Be Lowered Safely in Older Adults with Lacunar Stroke? The Secondary Prevention of Small Subcortical Strokes Study Experience

    PubMed Central

    White, Carole L.; Szychowski, Jeff M.; Pergola, Pablo E.; Field, Thalia S.; Talbert, Robert; Lau, Helena; Peri, Kalyani; Benavente, Oscar R.

    2015-01-01

    OBJECTIVES To determine safety and tolerability of lowering blood pressure in older adults with lacunar stroke. DESIGN Cohort study. SETTING The Secondary Prevention of Small Subcortical Strokes (SPS3) Trial, which compared the efficacy of two systolic blood pressure (SBP) targets (<130 mmHg and 130–149 mmHg) for secondary stroke prevention. PARTICIPANTS Of 3,020 SPS3 participants, 494 aged 75 and older at baseline were used in these analyses. MEASUREMENTS Rates of side effects related to lowering SBP and clinical outcomes, including stroke recurrence and vascular death, were examined. RESULTS Older participants achieved SBP levels similar to those of younger participants (mean SBP of 125 mmHg and 137 mmHg in lower and higher SBP target groups, respectively). At least once during the approximately 3.5 years of follow-up, 21% reported dizziness, and 15% reported lightheadedness when standing; the only significant difference between the younger and older groups was unsteadiness when standing (23% vs 32% respectively, P < .001). There was no difference according to treatment group. In younger adults, recurrent stroke was less likely in the lower than the higher SBP group (hazard ratio (HR) = 0.77, 95% confidence interval (CI) = 0.59–1.01) but not in older participants (HR = 1.01, 95% CI = 0.59– 1.73), although the interaction was not significant (P = .39). The lower SBP target was associated with a significant reduction in vascular death in older participants (HR = 0.42, 95% CI = 0.18–0.98), with a significant interaction between age and SBP group (P = .049). CONCLUSION Except for unsteadiness when standing, there was no difference according to age in individuals with lacunar stroke with respect to side effects potentially related to lowering blood pressure. Although the lower SBP target was not associated with lower likelihood of recurrent stroke, these exploratory analyses suggested a possible benefit related to vascular death. PMID:25850462

  17. Matrix cracking in brittle-matrix composites with tailored interfaces

    SciTech Connect

    Danchaivijit, S.; Chao, L.Y.; Shetty, D.K.

    1995-10-01

    Matrix cracking from controlled through cracks with bridging filaments was studied in a model unidirectional composite of SiC filaments in an epoxy-bonded alumina matrix. An unbonded, frictional interface was produced by moderating the curing shrinkage of the epoxy with the alumina filler and coating the filaments with a releasing agent. Uniaxial tension test specimens (2.5 x 25 x 125 mm) with filament-bridged through cracks were fabricated by a novel two-step casting technique involving casting, precracking and joining of cracked and uncracked sections. Distinct matrix-cracking stresses, corresponding to the extension of the filament-bridged cracks, were measured in uniaxial tension tests using a high-sensitivity extensometer. The crack-length dependence of the matrix-cracking stress was found to be in good agreement with the prediction of a fracture-mechanics analysis that employed a new crack-closure force-crack-opening displacement relation in the calculation of the stress intensity for fiber-bridged cracks. The prediction was based on independent experimental measurements of the matrix fracture toughness (K{sub cm}), the interfacial sliding friction stress ({tau}) and the residual stress in the matrix ({sigma}{sub m}{sup I}). The matrix-cracking stress for crack lengths (2a) greater than 3 mm was independent of the crack length and agreed with the prediction of the steady-state theory of Budiansky, Hutchinson and Evans. Tests on specimens without the deliberately introduced cracks indicated a matrix-cracking stress significantly higher than the steady-state stress.

  18. Automated quantification of pulmonary emphysema from computed tomography scans: comparison of variation and correlation of common measures in a large cohort

    NASA Astrophysics Data System (ADS)

    Keller, Brad M.; Reeves, Anthony P.; Yankelevitz, David F.; Henschke, Claudia I.

    2010-03-01

    The purpose of this work was to retrospectively investigate the variation of standard indices of pulmonary emphysema from helical computed tomographic (CT) scans as related to inspiration differences over a 1 year interval and determine the strength of the relationship between these measures in a large cohort. 626 patients that had 2 scans taken at an interval of 9 months to 15 months (μ: 381 days, σ: 31 days) were selected for this work. All scans were acquired at a 1.25mm slice thickness using a low dose protocol. For each scan, the emphysema index (EI), fractal dimension (FD), mean lung density (MLD), and 15th percentile of the histogram (HIST) were computed. The absolute and relative changes for each measure were computed and the empirical 95% confidence interval was reported both in non-normalized and normalized scales. Spearman correlation coefficients are computed between the relative change in each measure and relative change in inspiration between each scan-pair, as well as between each pair-wise combination of the four measures. EI varied on a range of -10.5 to 10.5 on a non-normalized scale and -15 to 15 on a normalized scale, with FD and MLD showing slightly larger but comparable spreads, and HIST having a much larger variation. MLD was found to show the strongest correlation to inspiration change (r=0.85, p<0.001), and EI, FD, and HIST to have moderately strong correlation (r = 0.61-0.74, p<0.001). Finally, HIST showed very strong correlation to EI (r = 0.92, p<0.001), while FD showed the least strong relationship to EI (r = 0.82, p<0.001). This work shows that emphysema index and fractal dimension have the least variability overall of the commonly used measures of emphysema and that they offer the most unique quantification of emphysema relative to each other.

  19. Effects of neighborhood socioeconomic status on blood pressure in older adults

    PubMed Central

    Wagner, Katia Jakovljevic Pudla; Boing, Antonio Fernando; Subramanian, SV; Höfelmann, Doroteia Aparecida; D’Orsi, Eleonora

    2016-01-01

    ABSTRACT OBJECTIVE To test if the neighborhood socioeconomic status is associated with systolic blood pressure and hypertension in older adults. METHODS A cross-sectional population-based study with a sample of 1,705 older adults from Florianópolis, SC, Southern Brazil. The contextual variable used was the average years of schooling of the head of the household in census tracts. Participants were considered hypertensive when the systolic blood pressure was ≥ 140 mmHg, diastolic ≥ 90 mmHg, or both. Additionally, the use of antihypertensive medication was also considered. Data were analyzed by using multilevel models of logistic and linear regression. RESULTS The average age of the sample was 70.7 years and the average of systolic and diastolic blood pressure was 133.5 mmHg (SD = 20.5 mmHg) and 81.9 mmHg (SD = 12.5 mmHg), respectively. The systolic blood pressure was 4.46 mmHg (95%CI 1.00–7.92) higher and the chance of hypertension was 1.80 (95%CI 1.26–2.57) among those who lived in census tracts with lower level of schooling. When the use of antihypertensive medication was combined with blood pressure levels, none association was found between the outcome and the level of schooling of the census tract. CONCLUSIONS Analytical models more robust (such as multilevel analysis) in Brazil are still little used, with a small number of articles published. Neighborhood socioeconomic status is associated with systolic blood pressure and the chance of hypertension, regardless of individual characteristics. PMID:28099662

  20. [Preparation and release mechanism of gestodene reservoir-type intravaginal rings].

    PubMed

    Li, Chun-Xiao; Wang, Yan-Kun; Ning, Mei-Ying

    2014-03-01

    This study taking gestodene (GEST) as a model, investigated the factors affecting reservoir-type intravaginal ring (IVR)'s drug release. This paper reported a gestodene intravaginal ring of reservoir design, comprising a gestodene silicone elastomer core encased in a non-medicated silicone sheath, separately manufactured by reaction injection moulding at 80 degrees C and heating vulcanization at 130 degrees C is reported. The test investigated the factors affecting drug release through a single variable method, taking the drug release rates of 21 days as standards. When changing the thickness of the controlling sheath outside, the ratio of the first day of drug release and mean daily release (MDR), named the relatively burst effect, is closing to 1 with the thickness of controlling sheath increasing, while the 1.25 mm sheath corresponding to 1.04 controlled the burst release effectively; a positive correlation (r = 0.992 2) existed between the average drug release (Q/t) and drug loading (A) within a certain range. The C6-165 controlling sheath with high solubility of GEST is easier to achieve controlled release of the drug; GEST crystalline power is more effective to implement controlled release of drugs among difficent states of the drug. A 1/4 fractional segment core gives a relatively burst effect of 1.76, while the 1/1 and 1/2 are 1.93 and 1.87 separately, at the same drug loading, concluding that use of a fractional segment core would allow development of a suitable GEST reservoir IVR. In summary, GEST reservoir-type IVR could be adjusted by the thickness of controlling sheath, the loading of drug, the material properties of controlling sheath, the dispersion state of drug, the additive composition and structure of intravaginal ring, to control the drug release behavior and achieve the desired drug release rate.

  1. Manual discrimination of force

    NASA Technical Reports Server (NTRS)

    Pang, Xiao-Dong; Tan, HONG-Z.; Durlach, Nathaniel I.

    1991-01-01

    Optimal design of human-machine interfaces for teleoperators and virtual-environment systems which involve the tactual and kinesthetic modalities requires knowledge of the human's resolving power in these modalities. The resolution of the interface should be appropriately matched to that of the human operator. We report some preliminary results on the ability of the human hand to distinguish small differences in force under a variety of conditions. Experiments were conducted on force discrimination with the thumb pushing an interface that exerts a constant force over the pushing distance and the index finger pressing against a fixed support. The dependence of the sensitivity index d' on force increment can be fit by a straight line through the origin and the just-noticeable difference (JND) in force can thus be described by the inverse of the slope of this line. The receiver operating characteristic (ROC) was measured by varying the a priori probabilities of the two alternatives, reference force and reference force plus an increment, in one-interval, two-alternative, forced-choice experiments. When plotted on normal deviate coordinates, the ROC's were roughly straight lines of unit slope, thus supporting the assumption of equal-variance normal distributions and the use of the conventional d' measure. The JND was roughly 6-8 percent for reference force ranging from 2.5 to 10 newtons, pushing distance from 5 to 30 mm, and initial finger-span from 45 to 125 mm. Also, the JND remained the same when the subjects were instructed to change the average speed of pushing from 23 to 153 mm/sec. The pushing was terminated by reaching either a wall or a well, and the JND's were essentially the same in both cases.

  2. Morphological evaluation of eccentric sets guide-plates of dcp-l 4.5 mm

    PubMed Central

    Borges, José Humberto de Souza; da Silva Filho, Antonio Lisboa; Pereira Neto, Francisco; Daher, Walter Rodrigo; de Mesquita, Alessandro Queiroz; Freitas, Anderson

    2012-01-01

    Objective To carry out isolated and comparative evaluations of the measurements of the set eccentric guide plates used in 4.5mm surgical implants, and to determine the effect of these measurements on compression strength. Methods Four eccentric guides, four large dynamic compression plates (L-DCP) from four local manufacturers, and a Vonder® 200 mm caliper brand were used. Five standard parameter measurements were created for the set eccentric guide-plate, which were identified as A to E. Four sets were made, using materials of the same factory, and identified as groups I to IV. The analyses were performed by measuring all the parameters from a ventral view of the plate, with the eccentric guide placed in the plate hole. Results Groups I and II showed the same values for all the parameters. All the groups showed the same measurements for E = 8.15 e B = 3.60. Group III: A = 8.10mm, C = 3.25mm, D = 1.25mm. Group IV: A = 7.00mm, C = 3.10mm, D = 0.30mm. Maximum compression force was (F Max.): Group I 80.58 N, Group. II: F Max. 81.63 N, Group. III: F Max. 36.32N, Group. IV: F Max. 37.52N Conclusion The measurements evaluated show a lack of standardization in the manufacture of orthopedic instruments and its effects on the values for compression strength. Level of Evidence: Level III, analytical study. PMID:24453573

  3. A reassessment of P2X7 receptor inhibition as a neuroprotective strategy in rat models of contusion injury.

    PubMed

    Marcillo, Alexander; Frydel, Beata; Bramlett, Helen M; Dietrich, W Dalton

    2012-02-01

    These experiments were completed as part of an NIH "Facilities of Research Excellence in Spinal Cord Injury" contract to support independent replication of published studies that could be considered for eventual clinical testing. Recent studies have reported that selective inhibition of the P2X7 receptor improves both the functional and histopathological consequences of a contusive spinal cord injury (SCI) in rats. We repeated two published studies reporting the beneficial effects of pyridoxal-5'-phosphate-6-azophenyl-2'-4'-disulphonic acid (PPADS) or Brilliant blue G (BBG) treatment after SCI (Wang et al., 2004 and Peng et al., 2009). Mild thoracic SCI was first produced in Experiment 1 by means of the MASCIS impactor at T10 (height 6.25 mm, weight 10 g) followed by intraspinal administration of a P2X7 antagonist (2 μl/10 mM) after injury. Treatment with PPADS or another highly selective P2X7R antagonist Brilliant Blue G (BBG) (2 μl/02 mM) did not improve locomotive (BBB rating scale) over a 7 week period compared to vehicle treated rats. Also, secondary histopathological changes in terms of overall lesion and cavity volume were not significantly different between the PPADS, BBG, and vehicle treated animals. In the second experiment, the systemic administration of BBG (10 or 50 mg/kg, iv) 15 min, 24 and 72 h after moderate (12.5 mm) SCI failed to significantly improve motor recovery or histopathological outcome over the 6 week observational period. Although we cannot conclude that there will be no long-term beneficial effects in other spinal cord injury models using selective P2X7 receptor antagonists at different doses or treatment durations, we caution researchers that this potentially exciting therapy requires further preclinical investigations before the implementation of clinical trials targeting severe SCI patients.

  4. Multislice computerized tomography angiography in the evaluation of intracranial aneurysms: a comparison with intraarterial digital subtraction angiography.

    PubMed

    Wintermark, Max; Uske, Antoine; Chalaron, Marc; Regli, Luca; Maeder, Philippe; Meuli, Reto; Schnyder, Pierre; Binaghi, Stefano

    2003-04-01

    The goal of this study was to assess the diagnostic accuracy of computerized tomography (CT) angiography performed with the aid of multislice technology (MSCT angiography) in the investigation of intracranial aneurysms, by comparing this method with intraarterial digital subtraction (IADS) angiography. Fifty consecutive adult patients, who successively underwent MSCT angiography (four rows) and IADS angiography of intracranial vessels, were prospectively identified. The MSCT angiography studies consisted of 1.25-mm slices, with 0.8-mm reconstruction intervals, a pitch of 0.75, and timing determined by a test bolus. Two neuroradiologists, who were blinded to the initial interpretation of the MSCT angiograms as well as to those of the IADS angiograms, independently reviewed the MSCT angiograms for the detection and characterization of intracranial aneurysms. Forty-nine intracranial aneurysms were identified in 40 patients; 33 of these lesions were responsible for subarachnoid hemorrhage. The sensitivity, specificity, and accuracy of MSCT angiography in the detection of intracranial aneurysms were 94.8, 95.2, and 94.9%, respectively, on a per-aneurysm basis and 99, 95.2, and 98.3%, respectively, on a per-patient basis. Interobserver agreement was 98%. There was an excellent correlation between aneurysm size assessed using MSCT angiography and that determined by IADS angiography (slope = 0.916, r = 0.877, p < 0.001); however, 2 mm stood as the cutoff size below which the sensitivity of MSCT angiography was statistically lower. That method displayed great accuracy in characterizing the morphological characteristics of the aneurysm. Multislice CT angiography is an accurate and robust noninvasive screening test for intracranial aneurysms. It performs better than that reported for single-slice CT angiography. Introduction of eight- and especially 16-row MSCT angiography will provide further progression through thinner slices, a lower pitch, and a purely arterial phase.

  5. SU-E-I-18: CT Scanner QA Using Normalized CTDI Ratio

    SciTech Connect

    Randazzo, M; Tambasco, M; Russell, B

    2014-06-01

    Purpose: To create a ratio of weighted computed tomography dose index (CTDIw) data normalized to in-air measurements (CTDIair) as a function of beam quality to create a look-up table for frequent, rapid quality assurance (QA) checks of CTDI. Methods: The CTDIw values were measured according to TG-63 protocol using a pencil ionization chamber (Unfors Xi CT detector) and head and body Polymethyl methacrylate (PMMA) phantoms (16 and 32 cm diameter, respectively). Single scan dose profiles were measured at each clinically available energy (80,100,120,140 kVp) on three different CT scanners (two Siemens SOMATOM Definition Flash and one GE Optima), using a tube current of 400 mA, a one second rotation time, and the widest available beam width (32 × 0.6 mm and 16 × 1.25 mm, respectively). These values were normalized to CTDIair measurements using the same conditions as CTDIw. The ratios (expressed in cGy/R) were assessed for each scanner as a function of each energy's half value layer (HVL) paired with the phantom's appropriate bow tie filter measured in mmAl. Results: Normalized CTDI values vary linearly with HVL for both the head and body phantoms. The ratios for the two Siemens machines are very similar at each energy. Compared to the GE scanner, these values vary between 10–20% for each kVp setting. Differences in CTDIair contribute most to the deviation of the ratios across machines. Ratios are independent of both mAs and collimation. Conclusion: Look-up tables constructed of normalized CTDI values as a function of HVL can be used to derive CTDIw data from only three in-air measurements (one for CTDIair and two with added filtration for HVL) to allow for simple, frequent QA checks without CT phantom setup. Future investigations will involve comparing results with Monte Carlo simulations for validation.

  6. Research and Development of Ultra-High Strength X100 Welded Pipe

    NASA Astrophysics Data System (ADS)

    Chuanguo, Zhang; Lei, Zheng; Ping, Hu; Bei, Zhang; Kougen, Wu; Weifeng, Huang

    Ultra-high strength X100 welded pipe can be used in the construction of long distance oil and gas pipeline to improve transmission capacity and reduce operation cost. By using the way of thermo-simulation and pilot rolling, the CCT (Continuous Cooling Transformation) diagram and the relationship between ACC (Accelerated Cooling) parameters, microstructure and mechanical properties were studied for the designed X100 pipeline steel with low carbon, high manganese and niobium micro-alloyed composition in lab. The analysis of CCT diagram indicates that the suitable hardness and microstructure can be obtained in the cooling rate of 20 80°C/sec. The pilot rolling results show that the ACC cooling start temperature below Ar3 phase transformation point is beneficial to increase uniform elongation, and the cooling stop temperature of 150 350°C is helpful to obtain high strength and toughness combination. Based on the research conclusions, the X100 plate and UOE pipe with dimension in O.D.1219×W.T.14.8mm, O.D.1219×W.T.17.8mm, designed for the natural gas transmission pipeline, were trial produced. The manufactured pipe body impact absorbed energy at -10°C is over 250J. The DWTT shear area ratio at 0°C is over 85%. The transverse strength meets the X100 grade requirement, and uniform elongation is over 4%. The X100 plate and UOE pipe with dimension in O.D.711×W.T.20.0mm, O.D.711×W.T.12.5mm, designed for an offshore engineering, were also trial produced. The average impact absorbed energy of pipe body at -30°C is over 200J. The average impact absorbed energy of HAZ (Heat-affected zone) and WM (Welded Seam) at -30°C is over 100J. And the good pipe shapes were obtained

  7. Airborne sound insulation evaluation and flanking path prediction of coupled room

    NASA Astrophysics Data System (ADS)

    Tassia, R. D.; Asmoro, W. A.; Arifianto, D.

    2016-11-01

    One of the parameters to review the acoustic comfort is based on the value of the insulation partition in the classroom. The insulation value can be expressed by the sound transmission loss which converted into a single value as weighted sound reduction index (Rw, DnTw) and also have an additional sound correction factor in low frequency (C, Ctr) .In this study, the measurements were performed in two positions at each point using BSWA microphone and dodecahedron speaker as the sound source. The results of field measurements indicate the acoustic insulation values (DnT w + C) is 19.6 dB. It is noted that the partition wall not according to the standard which the DnTw + C> 51 dB. Hence the partition wall need to be redesign to improve acoustic insulation in the classroom. The design used gypsum board, plasterboard, cement board, and PVC as the replacement material. Based on the results, all the material is simulated in accordance with established standards. Best insulation is cement board with the insulation value is 69dB, the thickness of 12.5 mm on each side and the absorber material is 50 mm. Many factors lead to increase the value of acoustic insulation, such as the thickness of the panel, the addition of absorber material, density, and Poisson's ratio of a material. The prediction of flanking path can be estimated from noise reduction values at each measurement point in the class room. Based on data obtained, there is no significant change in noise reduction from each point so that the pathway of flanking is not affect the sound transmission in the classroom.

  8. The Effect of Regular Intake of Dry-Cured Ham Rich in Bioactive Peptides on Inflammation, Platelet and Monocyte Activation Markers in Humans

    PubMed Central

    Martínez-Sánchez, Sara María; Minguela, Alfredo; Prieto-Merino, David; Zafrilla-Rentero, María Pilar; Abellán-Alemán, José; Montoro-García, Silvia

    2017-01-01

    Background and aims: Dietary studies have shown that active biopeptides provide protective health benefits, although the mediating pathways are somewhat uncertain. To throw light on this situation, we studied the effects of consuming Spanish dry-cured ham on platelet function, monocyte activation markers and the inflammatory status of healthy humans with pre-hypertension. Methods: Thirty-eight healthy volunteers with systolic blood pressure of >125 mmHg were enrolled in a two-arm crossover randomized controlled trial. Participants received 80 g/day dry-cured pork ham of >11 months proteolysis or 100 g/day cooked ham (control product) for 4 weeks followed by a 2-week washout before “crossing over” to the other treatment for 4 more weeks. Soluble markers and cytokines were analyzed by ELISA. Platelet function was assessed by measuring P-selectin expression and PAC-1 binding after ADP (adenosine diphosphate) stimulation using whole blood flow cytometry. Monocyte markers of the pathological status (adhesion, inflammatory and scavenging receptors) were also measured by flow cytometry in the three monocyte subsets after the interventional period. Results: The mean differences between dry-cured ham and cooked ham followed by a time period adjustment for plasmatic P-selectin and interleukin 6 proteins slightly failed (p = 0.062 and p = 0.049, respectively), notably increased for MCP-1 levels (p = 0.023) while VCAM-1 was not affected. Platelet function also decreased after ADP stimulation. The expression of adhesion and scavenging markers (ICAM1R, CXCR4 and TLR4) in the three subsets of monocytes was significantly higher (all p < 0.05). Conclusions: The regular consumption of biopeptides contained in the dry-cured ham but absent in cooked ham impaired platelet and monocyte activation and the levels of plasmatic P-selectin, MCP-1 and interleukin 6 in healthy subjects. This study strongly suggests the existence of a mechanism that links dietary biopeptides and beneficial

  9. Reducing the Use of Pesticides with Site-Specific Application: The Chemical Control of Rhizoctonia solani as a Case of Study for the Management of Soil-Borne Diseases

    PubMed Central

    Le Cointe, Ronan; Simon, Thomas E.; Delarue, Patrick; Hervé, Maxime; Leclerc, Melen; Poggi, Sylvain

    2016-01-01

    Reducing our reliance on pesticides is an essential step towards the sustainability of agricultural production. One approach involves the rational use of pesticides combined with innovative crop management. Most control strategies currently focus on the temporal aspect of epidemics, e.g. determining the optimal date for spraying, regardless of the spatial mechanics and ecology of disease spread. Designing innovative pest management strategies incorporating the spatial aspect of epidemics involves thorough knowledge on how disease control affects the life-history traits of the pathogen. In this study, using Rhizoctonia solani/Raphanus sativus as an example of a soil-borne pathosystem, we investigated the effects of a chemical control currently used by growers, Monceren® L, on key epidemiological components (saprotrophic spread and infectivity). We tested the potential “shield effect” of Monceren® L on pathogenic spread in a site-specific application context, i.e. the efficiency of this chemical to contain the spread of the fungus from an infected host when application is spatially localized, in our case, a strip placed between the infected host and a recipient bait. Our results showed that Monceren® L mainly inhibits the saprotrophic spread of the fungus in soil and may prevent the fungus from reaching its host plant. However, perhaps surprisingly we did not detect any significant effect of the fungicide on the pathogen infectivity. Finally, highly localized application of the fungicide—a narrow strip of soil (12.5 mm wide) sprayed with Monceren® L—significantly decreased local transmission of the pathogen, suggesting lowered risk of occurrence of invasive epidemics. Our results highlight that detailed knowledge on epidemiological processes could contribute to the design of innovative management strategies based on precision agriculture tools to improve the efficacy of disease control and reduce pesticide use. PMID:27668731

  10. Ignition and flame characteristics of cryogenic hydrogen releases

    DOE PAGES

    Panda, Pratikash P.; Hecht, Ethan S.

    2017-01-01

    In this work, under-expanded cryogenic hydrogen jets were investigated experimentally for their ignition and flame characteristics. The test facility described herein, was designed and constructed to release hydrogen at a constant temperature and pressure, to study the dispersion and thermo-physical properties of cryogenic hydrogen releases and flames. In this study, a non-intrusive laser spark focused on the jet axis was used to measure the maximum ignition distance. The radiative power emitted by the corresponding jet flames was also measured for a range of release scenarios from 37 K to 295 K, 2–6 barabs through nozzles with diameters from 0.75 tomore » 1.25 mm. The maximum ignition distance scales linearly with the effective jet diameter (which scales as the square root of the stagnant fluid density). A 1-dimensional (stream-wise) cryogenic hydrogen release model developed previously at Sandia National Laboratories (although this model is not yet validated for cryogenic hydrogen) was exercised to predict that the mean mole fraction at the maximum ignition distance is approximately 0.14, and is not dependent on the release conditions. The flame length and width were extracted from visible and infra-red flame images for several test cases. The flame length and width both scale as the square root of jet exit Reynolds number, as reported in the literature for flames from atmospheric temperature hydrogen. As shown in previous studies for ignited atmospheric temperature hydrogen, the radiative power from the jet flames of cold hydrogen scales as a logarithmic function of the global flame residence time. The radiative heat flux from jet flames of cold hydrogen is higher than the jet flames of atmospheric temperature hydrogen, for a given mass flow rate, due to the lower choked flow velocity of low-temperature hydrogen. Lastly, this study provides critical information with regard to the development of models to inform the safety codes and standards of hydrogen infrastructure.« less

  11. Endovascular Stenting for Unsuccessful Angioplasty of the Aorta in Aortoarteritis

    SciTech Connect

    Tyagi, Sanjay; Kaul, Upkar A.; Arora, Ramesh

    1999-11-15

    Purpose: The efficacy and safety of endovascular stent implantation to correct dissection or a suboptimal result after percutaneous transluminal angioplasty (PTA) was evaluated in patients suffering from aortic stenosis due to aortoarteritis. Methods: Twelve children and young adults [aged (mean {+-} SD) 18.2 {+-} 8.7 years] underwent stent implantation after PTA of the aorta, seven for obstructive dissection, four for ineffective balloon dilatation, and one for recurrent restenosis. Nine patients underwent implantation of self-expandable stents and three received balloon-expandable Palmaz stents. Results: Stent implantation could be successfully performed in all 12 patients. After stent implantation, the peak systolic pressure gradient decreased from 91 {+-} 33.5 mmHg to 12.4 {+-} 12.5 mmHg (p < 0.001). The diameter of the stenosed segment increased from 4.6 {+-} 0.8 mm to 11.1 {+-} 1.9 mm (p < 0.001). The dissection was completely covered in all seven patients with dissection. Except for epigastric pain with vomiting in one patient, there was no complication. On follow-up, over 12-57 months (mean 26.8 {+-} 10.8 months), 11 patients (91.6%) had marked improvement in their blood pressure. Patients with congestive heart failure and claudication also showed improvement. Repeat catheterization in five patients, between 6-30 months (mean 16.8 {+-} 9.1 months) after stent implantation, showed sustained improvement in four and a fusiform, long segment, intrastent restenosis after 30 months in one child. The stenosis was safely redilated. Conclusion: Endovascular aortic stent implantation is safe and provides good immediate relief in patients with unsatisfactory results after balloon angioplasty. Improvement is sustained in most patients on intermediate-term follow-up.

  12. Estimation of Ground Water Recharge Using SWAT Model

    NASA Astrophysics Data System (ADS)

    Lee, D.; Chung, I.

    2006-12-01

    In this study the SWAT model was applied to estimate a shallow groundwater recharge at the watershed scale. The SWAT model is a semi-distributed comprehensive surface and subsurface flow model with the capability of simulating sediment and agricultural chemicals. The study site is Bocheongcheon watershed which is one of IHP experimental watersheds in Korea and the rainfall and stream flow have been monitored since 1984. The dominant land use types of the watershed are the mixed forest and agricultural land. The input data for SWAT model were prepared using the digital land use and soil maps with daily rainfall measured at ten rain gauge stations and the meteorological variables such as daily wind speed, relative humidity, solar radiation, and temperature collected within the watershed. The SWAT model was calibrated based on four years of daily stream flow data using the shuffled complex evolution global optimization method. Since there was no information for soil hydraulic properties, the various published pedotransfer functions were used for the specification of soil hydraulic conductivity. The annual recharge calculated from SWAT model ranged from 125 mm to 191 mm depending on the selected pedotransfer functions. Although the estimates of the regional groundwater recharge vary with the selection of pedotransfer functions, the performance measures between the simulated and measured daily stream flow are appeared to be similar. The result indicates that it is very difficult to identify a unique parameter set and the proper identification of spatially consistent soil hydraulic conductivity has an important implication for modeling groundwater recharge at the watershed scale using the spatially distributed watershed model such as SWAT.

  13. Gender Differences of Airway Dimensions in Anatomically Matched Sites on CT in Smokers

    PubMed Central

    Kim, Yu-Il; Schroeder, Joyce; Lynch, David; Newell, John; Make, Barry; Friedlander, Adam; Estépar, Raúl San José; Hanania, Nicola A.; Washko, George; Murphy, James R.; Wilson, Carla; Hokanson, John E.; Zach, Jordan; Butterfield, Kiel; Bowler, Russell P.

    2013-01-01

    Rationale and Objectives There are limited data on, and controversies regarding gender differences in the airway dimensions of smokers. Multi-detector CT (MDCT) images were analyzed to examine whether gender could explain differences in airway dimensions of anatomically matched airways in smokers. Materials and Methods We used VIDA imaging software to analyze MDCT scans from 2047 smokers (M:F, 1021:1026) from the COPDGene® cohort. The airway dimensions were analyzed from segmental to subsubsegmental bronchi. We compared the differences of luminal area, inner diameter, wall thickness, wall area percentage (WA%) for each airway between men and women, and multiple linear regression including covariates (age, gender, body sizes, and other relevant confounding factors) was used to determine the predictors of each airway dimensions. Results Lumen area, internal diameter and wall thickness were smaller for women than men in all measured airway (18.4 vs 22.5 mm2 for segmental bronchial lumen area, 10.4 vs 12.5 mm2 for subsegmental bronchi, 6.5 vs 7.7 mm2 for subsubsegmental bronchi, respectively p < 0.001). However, women had greater WA% in subsegmental and subsubsegmental bronchi. In multivariate regression, gender remained one of the most significant predictors of WA%, lumen area, inner diameter and wall thickness. Conclusion Women smokers have higher WA%, but lower luminal area, internal diameter and airway thickness in anatomically matched airways as measured by CT scan than do male smokers. This difference may explain, in part, gender differences in the prevalence of COPD and airflow limitation. PMID:21756032

  14. Thermal Stir Welding Development at Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Ding, Robert J.

    2008-01-01

    Solid state welding processes have become the focus of welding process development at NASA's Marshall Space Flight Center. Unlike fusion weld processes such as tungsten inert gas (TIG), variable polarity plasma arc (VPPA), electron beam (EB), etc., solid state welding processes do not melt the material during welding. The resultant microstructure can be characterized as a dynamically recrystallized morphology much different than the casted, dentritic structure typical of fusion weld processes. The primary benefits of solid state processes over fusion weld processes include superior mechanic properties and the elimination of thermal distortion and residual stresses. These solid state processes attributes have profoundly influenced the direction of advanced welding research and development within the NASA agency. Thermal Stir Welding (TSW) is a new solid state welding process being developed at the Marshall Space Flight Center. Unlike friction stir welding, the heating, stirring and forging elements of the weld process can be decoupled for independent control. An induction coil induces energy into a workpiece to attain a desired plastic temperature. An independently controlled stir rod, captured within non-rotating containment plates, then stirs the plasticized material followed by forging plates/rollers that work the stirred weld joint. The independent control (decoupling) of heating, stirring and forging allows, theoretically, for the precision control of microstructure morphology. The TSW process is being used to evaluate the solid state joining of Haynes 230 for ARES J-2X applications. It is also being developed for 500-in (12.5 mm) thick commercially pure grade 2 titanium for navy applications. Other interests include Inconel 718 and stainless steel. This presentation will provide metallurgical and mechanical property data for these high melting temperature alloys.

  15. Summer habitat use by Columbia River redband trout in the Kootenai River drainage, Montana

    USGS Publications Warehouse

    Muhlfeld, Clint C.; Bennett, David H.

    2001-01-01

    The reported decline in the abundance, distribution, and genetic diversity of Columbia River redband trout Oncorhynchus mykiss gairdneri (a rainbow trout subspecies) has prompted fisheries managers to investigate their habitat requirements, identify critical habitat, and develop effective conservation and recovery programs. We analyzed the microhabitat, mesohabitat, and macrohabitat use and distribution of Columbia River redband trout by means of snorkel surveys in two watersheds in the Kootenai River drainage, Montana and Idaho, during the summers of 1997 and 1998. Juvenile (36–125 mm total length, TL) and adult (>=126 mm TL) fish preferred deep microhabitats (>=0.4 m) with low to moderate velocities (<=0.5 m/s) adjacent to the thalweg. Conversely, age-0 (<=35 mm) fish selected slow water (<=0.1 m/s) and shallow depths (<=0.2 m) located in lateral areas of the channel. Age-0, juvenile, and adult fish strongly selected pool mesohabitats and avoided riffles; juveniles and adults generally used runs in proportion to their availability. At the macrohabitat scale, density of Columbia River redband trout (35 mm) was positively related to the abundance of pools and negatively related to stream gradient. The pool: riffle ratio, gradient, and stream size combined accounted for 80% of the variation in density among 23 stream reaches in five streams. Our results demonstrate that low-gradient, medium-elevation reaches with an abundance of complex pools are critical areas for the production of Columbia River redband trout. These data will be useful in assessing the impacts of land-use practices on the remaining populations and may assist with habitat restoration or enhancement efforts.

  16. Effects of shielding gas hydrogen content on the arc behavior in gas tungsten arc welding

    SciTech Connect

    Onsoien, M.I.; Olson, D.L.; Liu, S.

    1994-12-31

    The primary role of the shielding gas in gas tungsten arc welding (GTAW) is to protect the weld pool and tungsten electrode from the oxygen and nitrogen in the surrounding atmosphere. Traditionally inert gases such as argon and helium have been used, either as pure gases or mixed with each other. However, additions of small amounts of hydrogen have been reported to improve weld bead penetration and enable higher welding speeds to be used. The present work was performed to investigate the effect of small hydrogen additions on the arc behavior in GTAW, and to further the fundamental understanding of the effect of shielding gas on arc characteristics. GTAW bead-on-plate welds were made on 12.5 mm x 150 mm x 75 mm Type 304 stainless steel test coupons. The welding current, voltage, and their variations were continuously monitored during welding. After welding, each test coupon was sectioned and prepared using standard metallographic techniques and etched in Vilella`s etch for macroexamination of the weld bead cross section. Bead width, depth, and cross-sectional area were measured using a LECO image analysator system. The influence of hydrogen content in an argon has tungsten arc was characterized. The electrical behavior of the arc, including the arc resistance, was measured as a function of current and hydrogen content. A better fundamental understanding of arc behavior and energy transfer was achieved using these experimental gas mixes. The results allow the following conclusions to be drawn: (1) Small additions of hydrogen in the argon based shielding gas in gas tungsten arc welding significantly change the weld bead geometry due to changes in the arc column. (2) Selection of the right argon, hydrogen shielding gas mixture to give the optimum arc column characteristics for a given condition can improve weld quality and increase productivity. (3) The resistance of the arc column was found to be an adequate parameter to describe the arc column behavior.

  17. Late Quaternary slip history of the Mill Creek strand of the San Andreas fault in San Gorgonio Pass, southern California: The role of a subsidiary left-lateral fault in strand switching

    USGS Publications Warehouse

    Kendrick, Katherine J.; Matti, Jonathan; Mahan, Shannon

    2015-01-01

    The fault history of the Mill Creek strand of the San Andreas fault (SAF) in the San Gorgonio Pass region, along with the reconstructed geomorphology surrounding this fault strand, reveals the important role of the left-lateral Pinto Mountain fault in the regional fault strand switching. The Mill Creek strand has 7.1–8.7 km total slip. Following this displacement, the Pinto Mountain fault offset the Mill Creek strand 1–1.25 km, as SAF slip transferred to the San Bernardino, Banning, and Garnet Hill strands. An alluvial complex within the Mission Creek watershed can be linked to palinspastic reconstruction of drainage segments to constrain slip history of the Mill Creek strand. We investigated surface remnants through detailed geologic mapping, morphometric and stratigraphic analysis, geochronology, and pedogenic analysis. The degree of soil development constrains the duration of surface stability when correlated to other regional, independently dated pedons. This correlation indicates that the oldest surfaces are significantly older than 500 ka. Luminescence dates of 106 ka and 95 ka from (respectively) 5 and 4 m beneath a younger fan surface are consistent with age estimates based on soil-profile development. Offset of the Mill Creek strand by the Pinto Mountain fault suggests a short-term slip rate of ∼10–12.5 mm/yr for the Pinto Mountain fault, and a lower long-term slip rate. Uplift of the Yucaipa Ridge block during the period of Mill Creek strand activity is consistent with thermochronologic modeled uplift estimates.

  18. Quantifying isocenter measurements to establish clinically meaningful thresholds.

    PubMed

    Denton, Travis R; Shields, Lisa B E; Howe, Jonathan N; Spalding, Aaron C

    2015-03-08

    A dataset range of isocenter congruency verification tests have been examined from a statistical perspective for the purpose of establishing tolerance levels that are meaningful, based on the fundamental limitation of linear accelerator isocentricity and the demands of a high-precision stereotactic radiosurgery program. Using a laser-defined isocenter, a total of 149 individual isocenter congruency tests were examined with recorded values for ideal spatial corrections to the isocenter test tool. These spatial corrections were determined from radiation exposures recorded on an electronic portal imaging device (EPID) at various gantry, collimator, and treatment couch combinations. The limitations of establishing an ideal isocenter were quantified from each variable which contributed to uncertainty in isocenter definition. Individual contributors to uncertainty, specifically, daily positioning setup errors, gantry sag, multileaf collimator (MLC) offset, and couch walkout, were isolated from isocenter congruency measurements to determine a clinically meaningful isocenter measurement. Variations in positioning of the test tool constituted, on average, 0.38 mm magnitude of correction. Gantry sag and MLC offset contributed 0.4 and 0.16 mm, respectively. Couch walkout had an average degrading effect to isocenter of 0.72 mm. Considering the magnitude of uncertainty contributed by each uncertainty variable and the nature of their combination, an appropriate schedule action and immediate action level were determined for use in analyzing daily isocenter congruency test results in a stereotactic radiosurgery (SRS) program. The recommendations of this study for this linear accelerator include a schedule action level of 1.25 mm and an immediate action level of 1.50mm, requiring prompt correction response from clinical medical physicists before SRS or stereotactic body radiosurgery (SBRT) is administered. These absolute values were derived from considering relative data from a specific linear accelerator and, therefore, represent a means by which a numerical quantity can be used as a test threshold with relative specificity to a particular linear accelerator.

  19. Expression of HIF-1 alpha in irradiated tissue is altered by topical negative-pressure therapy.

    PubMed

    Grimm, Andreas; Dimmler, Arno; Stange, Sebastian; Labanaris, Apostolos; Sauer, Rolf; Grabenbauer, Gerhard; Horch, Raymund E

    2007-03-01

    Despite the enormous therapeutic potential of modern radiotherapy, common side effects such as radiation-induced wound healing disorders remain a well-known clinical phenomenon. Topical negative pressure therapy (TNP) is a novel tool to alleviate intraoperative, percutaneous irradiation or brachytherapy. Since TNP has been shown to positively influence the perfusion of chronic, poorly vascularized wounds, the authors applied this therapeutic method to irradiated wounds and investigated the effect on tissue oxygenation in irradiated tissue in five patients. With informed patients' consent, samples prior to and 4 and 8 days after continuous TNP with -125 mmHg were obtained during routine wound debridements. Granulation tissue was stained with hematoxylin-eosin, and additionally with CD31, HIF-1 alpha (hypoxia-inducible factor-1 alpha), and D2-40 to detect blood vessels, measure indirect signs of hypoxia, and lymph vessel distribution within the pre- and post-TNP samples. In this first series of experiments, a positive influence of TNP onto tissue oxygenation in radiation-induced wounds could be demonstrated. TNP led to a significant decrease of 53% HIF-1 alpha-positive cell nuclei. At the same time, a slight reduction of CD31-stained capillaries was seen in comparison to samples before TNP. Immunostaining with D2-40 revealed an increased number of lymphatic vessels with distended lumina and an alteration of the parallel orientation within the post-TNP samples. This study is, to the authors' knowledge, the first report on a novel previously not described histological marker to demonstrate the effects of TNP on HIF-1 alpha expression as an indirect marker of tissue oxygenation in irradiated wounds, as demonstrated by a reduction of HIF-1 alpha concentration after TNP. Since this observation may be of significant value to develop possible new strategies to treat radiation-induced tissue injury, further investigations of HIF-1 alpha regulation under TNP are warranted.

  20. Surface analysis of study models generated from OrthoCAD and cone-beam computed tomography imaging.

    PubMed

    Lightheart, Kurtis G; English, Jeryl D; Kau, Chung H; Akyalcin, Sercan; Bussa, Harry I; McGrory, Kathleen R; McGrory, Kevin J

    2012-06-01

    The purpose of this research was to determine the accuracy of digital models generated by cone-beam computed tomography and compare it with that of OrthoCAD models (Cadent, Carlstadt, NJ) for orthodontic diagnosis and treatment planning by using surface area analysis. Two sets of maxillary and mandibular digital models of 30 subjects were obtained. The models were made from impressions scanned with OrthoCAD and by conversion of related cone-beam computed tomography files. Each patient's matched pairs of maxillary and mandibular models were superimposed by using a software program and a best-fit algorithm; surface-to-surface analysis was then performed. The average linear differences between the 2 files at all points on the surfaces were measured, and tolerance levels of 0.25, 0.5, 0.75, 1.0, 1.25, and 1.5 mm were set to determine the surface correlation amounts between the 2 files. Additionally, 6 linear measurements from predetermined landmarks were also measured and analyzed. The average maxillary model linear difference was 0.28 to 0.60 mm, whereas the average mandibular model linear difference ranged between 0.34 and 0.61 mm. Greater than a 90% surface correlation was obtained on average at 1.00 mm in the maxillary models and at 1.25 mm in the mandibular models. The mean differences obtained from the linear measurements of the maxillary and mandibular models were 0.071 and 0.018 mm, respectively. Surface-to-surface analysis of OrthoCAD and digital models generated by cone-beam computed tomography pointed to a fair overlap between the protocols. The accuracy of digital models generated by cone-beam computed tomography is adequate for initial diagnosis and treatment planning in orthodontics. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  1. Graft laceration and pullout strength of soft-tissue anterior cruciate ligament reconstruction: in vitro study comparing titanium, poly-d,l-lactide, and poly-d,l-lactide-tricalcium phosphate screws.

    PubMed

    Zantop, Thore; Weimann, Andre; Schmidtko, Romana; Herbort, Mirco; Raschke, Michael J; Petersen, Wolf

    2006-11-01

    The aim of part 1 of this study was to compare the structural properties of tibia-graft-interference screw constructs of soft-tissue graft fixation via the anterior cruciate ligament (ACL) by use of different interference screws. In part 2 the influence of graft laceration as a result of 1 single interference screw insertion on the mechanical properties of the graft was evaluated. In part 1 of the study, in a bovine knee model, soft-tissue graft fixation with titanium, biodegradable poly-D,L-lactide (PLDLA), and PLDLA-tricalcium phosphate (TCP) interference screws was performed, and the structural properties were determined by use of a materials testing machine at a rate of 12.5 mm/s. In part 2 the bone was cut after 1 single insertion of titanium, PLDLA, or PLDLA-TCP interference screws, and the mechanical properties of the graft were determined. Soft-tissue graft fixation with a biodegradable PLDLA interference screw showed a statistically significantly higher maximum load when compared with PLDLA-TCP and titanium interference screws. PLDLA-TCP screw fixation revealed a significantly higher ultimate load than titanium screw fixation. The mechanical properties of the grafts after 1 single insertion of PLDLA-TCP interference screws showed a statistically significantly higher stiffness, yield load, and maximum load when compared with the PLDLA and titanium interference screw groups. The results of this study suggest that the use of a titanium screw to fix a soft-tissue graft in cruciate ligament reconstruction surgery may cause damage to the graft. Soft-tissue ACL reconstruction fixed with a PLDLA interference screw resulted in a significantly higher pullout strength than ACL reconstructions fixed with a PLDLA-TCP or titanium interference screw. In contrast to fixation with a biodegradable interference screw, fixation with a titanium interference screw may damage the integrity of a soft-tissue graft in cruciate ligament reconstruction and should therefore be avoided.

  2. Ignition and flame characteristics of cryogenic hydrogen releases

    SciTech Connect

    Panda, Pratikash P.; Hecht, Ethan S.

    2017-01-01

    In this work, under-expanded cryogenic hydrogen jets were investigated experimentally for their ignition and flame characteristics. The test facility described herein, was designed and constructed to release hydrogen at a constant temperature and pressure, to study the dispersion and thermo-physical properties of cryogenic hydrogen releases and flames. In this study, a non-intrusive laser spark focused on the jet axis was used to measure the maximum ignition distance. The radiative power emitted by the corresponding jet flames was also measured for a range of release scenarios from 37 K to 295 K, 2–6 barabs through nozzles with diameters from 0.75 to 1.25 mm. The maximum ignition distance scales linearly with the effective jet diameter (which scales as the square root of the stagnant fluid density). A 1-dimensional (stream-wise) cryogenic hydrogen release model developed previously at Sandia National Laboratories (although this model is not yet validated for cryogenic hydrogen) was exercised to predict that the mean mole fraction at the maximum ignition distance is approximately 0.14, and is not dependent on the release conditions. The flame length and width were extracted from visible and infra-red flame images for several test cases. The flame length and width both scale as the square root of jet exit Reynolds number, as reported in the literature for flames from atmospheric temperature hydrogen. As shown in previous studies for ignited atmospheric temperature hydrogen, the radiative power from the jet flames of cold hydrogen scales as a logarithmic function of the global flame residence time. The radiative heat flux from jet flames of cold hydrogen is higher than the jet flames of atmospheric temperature hydrogen, for a given mass flow rate, due to the lower choked flow velocity of low-temperature hydrogen. Lastly, this study provides critical information with regard to the development of models to inform the safety codes and standards of hydrogen infrastructure.

  3. Positive corona discharge in N_2 + CH_4 mixture at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Horvath, G.; Skalny, J. D.; Mason, N. J.; Zahoran, M.; Orszagh, J.

    2008-07-01

    Titan is considered as one of the few places in Solar system, where atmospheric and surface conditions could have produced organic molecules as precursors of higher hydrocarbons, nitriles or amino acids. Most of laboratory simulations of Titan's atmosphere were carried out at lower pressures presenting stratospheric conditions but there is poor knowledge about simulated reactions of Titan's troposphere. In our work an experimental investigation of products in positive coaxial corona discharge fed by mixture of N_2 and CH_4 with ratio of N_2:CH_4=98:2 in stationary regime has been made using UV spectroscopy. The measurements have been carried out at pressure of 1 bar and ambient temperature. The discharge reactor used for the treatment of the gas mixture consisted of a brass cylinder with diameter of 16 mm and length of 70 mm. A stainless steel and tungsten wires of diameter of 0.125 mm was centred inside the metal cylinder and was connected to the high voltage power supply. Coaxial corona discharge was generated by a Glassman high voltage power supply. The mixing ratio of methane and nitrogen was regulated by a MKS flow controllers. The reactor was placed in a Shimadzu VUV spectrometer for the in-situ measurements of absorbance of synthesized compounds. The measurements were focused on the UV analysis of time evolution of C_2H_2 and C_2H_4 concentrations and EMS study of deposited compounds on discharge electrodes (Figure 1). After a certain time a yellow- orange layer was formed on the active discharge electrode causing sparks and forming a dense rose-like spots on the covered electrode surface (Figure 2). Figure 1: EMS study of electrode surface. Figure 2: EMS picture of a treated electrode.

  4. Recovery of metallic concentrations from waste printed circuit boards via reverse floatation.

    PubMed

    He, Jingfeng; Duan, Chenlong

    2017-02-01

    Efficient disposal of waste printed circuit boards (PCBs) is favorable toward recovering valuable components and reducing pollution. Reverse floatation was used to recover metallic concentrations from waste PCBs. Basic properties and mineralogical characteristics of raw PCBs were tested and analyzed. Results indicated that the grade of metallic concentrations declined as the size fraction of PCBs decreased. The major metallic elements found in PCBs were Cu, Pb, and Sn, as well as trace elements were also found in fine PCB particles. Kerosene and terpenic oil were used as the collector and frother in the floatation experiments. The effects of various operational factors, including the feeding concentration, aeration rate, and agitation speed of floatation machine, on the floatation performance of -0.25mm PCBs were experimentally studied to determine optimal range. The floatation results suggested that the yield of sinks and grade of metallic concentrations diminished significantly with the decrease of size fraction of PCBs. The maximum yields of sinks and highest grades of metallic concentrations were 48.72% and 16.86%, 47.96% and 14.61%, 44.36% and 8.81%, with the optimum recoveries of metallic concentrations of 94.69%, 90.06%, and 75.96% for size fractions of 0.125-0.25mm, 0.074-0.125mm, and -0.074mm PCBs, respectively. The recovery efficiency of metallic concentrations declined as the size fraction decreased. The efficient overall recovery performance of metallic concentrations from waste PCBs was obtained via reverse floatation. This study provides an alternative approach for disposing waste PCBs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Assay of artemether, methylparaben and propylparaben in a formulated paediatric antimalarial dry suspension.

    PubMed

    Atemnkeng, Magnus A; Marchand, Els; Plaizier-Vercammen, Jacqueline

    2007-01-17

    Two HPLC-UV methods are described for the separate determination of artemether (AM) and the combined preservatives, methylparaben and propylparaben in a pharmaceutical dosage form. These analytes are contained in a dry suspension with a high amount of non-soluble excipients, some of which can interfere with the analysis. This makes their separation and analysis of the actives complex. Moreover, due to the wide difference in concentrations, the three analytes could not be quantitated simultaneously. Artemether was analysed using a reversed-phase Nucleosil C(18) column [5 microm, 125 mm x 4 mm (i.d.)] with a mixture of acetonitrile: potassium phosphate buffer pH 5.0 (0.05 M): water [48:32:10 (v/v/v)] as mobile phase. Due to the low solubility of the hydroxy benzoic acid esters in water, their sodium salts were used in the formulation. Complete separation of these preservatives was achieved on the same type of column as artemether using as eluent acetonitrile: potassium phosphate buffer pH 5.0 (0.05 M) (30:70, v/v). Quantitation was achieved with UV detection at 215 nm for artemether and 254 nm for the parabens, respectively. And in both methods, pump flow rate was 1.0 ml/min, sample injection volume 20 microl, ambient temperature maintained and no prior sample extraction methods were necessary throughout the experiments. Calibration curves were linear at concentration ranges of 4-16 microg/ml, 1-4 microg/ml and 1-10 mg/ml for methylparaben, propylparaben and artemether respectively. The excipient powder interference could be eliminated by diluting the sample and the analytes eluted at relatively short times using these systems. Both methods were further validated in terms of specificity, linearity, precision and accuracy. The procedures prescribed here are simple, selective and can be used for routine quality control and stability indicating tests involving the analysed compounds formulated in complex matrices.

  6. Foramen magnum size and involvement of its intraoccipital synchondroses in Crouzon syndrome.

    PubMed

    Rijken, Bianca F M; Lequin, Maarten H; de Rooi, Johan J; van Veelen, Marie-Lise C; Mathijssen, Irene M J

    2013-12-01

    Cranial sutures and synchondroses tend to close prematurely in patients with Crouzon syndrome. This influences their skull vault and skull base development and may involve in common disturbances such as increased intracranial pressure and cerebellar tonsillar herniation. The authors' hypothesis was that Crouzon patients patients have a smaller foramen magnum than controls because of premature fusion of the intraoccipital synchondroses, putting them at risk for cerebellar tonsillar herniation. Therefore, foramen magnum size and time of intraoccipital synchondroses closure were evaluated and were related to the presence and degree of cerebellar tonsillar herniation. The foramen magnum surface area and anteroposterior diameter were measured on three-dimensional computed tomographic scans of 27 Crouzon patients and 27 age-matched controls. Scans had a slice-thickness between 0.75 and 1.25 mm and were aligned in a three-dimensional reformatting platform. The t test was used to study size differences. Synchondroses were graded as described by Madeline and Elster and studied with ordinal logistic regression analysis. Crouzon patients had a smaller foramen magnum surface area (602 mm versus 767 mm, p < 0.001) and anteroposterior diameter (31 mm versus 35 mm, p < 0.001) compared with controls. Differences stayed constant over time. Intraoccipital synchondroses closed 3 to 9 months earlier in Crouzon patients than in controls (p < 0.05). Since intraoccipital synchondroses close earlier in Crouzon patients, from early life on their foramen magnum is smaller compared with controls. Within Crouzon patients, the presence of cerebellar tonsillar herniation could not be related to foramen magnum size. Risk, II.

  7. Bench-scale experimental determination of the thermal diffusivity of crushed tuff

    SciTech Connect

    Ryder, E.E.; Finley, R.E.; George, J.T.; Ho, C.K.; Longenbaugh, R.S.; Connolly, J.R.

    1996-06-01

    A bench-scale experiment was designed and constructed to determine the effective thermal diffusivity of crushed tuff. Crushed tuff particles ranging from 12.5 mm to 37.5 mm (0.5 in. to 1.5 in.) were used to fill a cylindrical volume of 1.58 m{sup 3} at an effective porosity of 0.48. Two iterations of the experiment were completed; the first spanning approximately 502 hours and the second 237 hours. Temperatures near the axial heater reached 700 degrees C, with a significant volume of the test bed exceeding 100 degrees C. Three post-test analysis techniques were used to estimate the thermal diffusivity of the crushed tuff. The first approach used nonlinear parameter estimation linked to a one dimensional radial conduction model to estimate thermal diffusivity from the first 6 hours of test data. The second method used the multiphase TOUGH2 code in conjunction with the first 20 hours of test data not only to estimate the crushed tuffs thermal diffusivity, but also to explore convective behavior within the test bed. Finally, the nonlinear conduction code COYOTE-II was used to determine thermal properties based on 111 hours of cool-down data. The post-test thermal diffusivity estimates of 5.0 x 10-7 m{sup 2}/s to 6.6 x 10-7 m{sup 2}/s were converted to effective thermal conductivities and compared to estimates obtained from published porosity-based relationships. No obvious match between the experimental data and published relationships was found to exist; however, additional data for other particle sizes and porosities are needed.

  8. Development of a high-resolution Si-PM-based gamma camera system.

    PubMed

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Imaizumi, Masao; Watabe, Tadashi; Shimosegawa, Eku; Hatazawa, Jun

    2011-12-07

    A silicon photomultiplier (Si-PM) is a promising photodetector for PET, especially for PET/MRI combined systems, due to its high gain, small size, and lower sensitivity to static magnetic fields. However, these properties are also promising for gamma camera systems for single-photon imaging. We developed an ultra-high-resolution Si-PM-based compact gamma camera system for small animals. Y(2)SiO(5):Ce (YSO) was selected as scintillators because of its high light output and no natural radioactivity. The gamma camera consists of 0.6 mm × 0.6 mm × 6 mm YSO pixels combined with a 0.1 mm thick reflector to form a 17 × 17 matrix that was optically coupled to a Si-PM array (Hamamatsu multi-pixel photon counter S11064-050P) with a 2 mm thick light guide. The YSO block size was 12 mm × 12 mm. The YSO gamma camera was encased in a 5 mm thick gamma shield, and a parallel hole collimator was mounted in front of the camera (0.5 mm hole, 0.7 mm separation, 5 mm thick). The two-dimensional distribution for the Co-57 gamma photons (122 keV) was almost resolved. The energy resolution was 24.4% full-width at half-maximum (FWHM) for the Co-57 gamma photons. The spatial resolution at 1.5 mm from the collimator surface was 1.25 mm FWHM measured using a 1 mm diameter Co-57 point source. Phantom and small animal images were successfully obtained. We conclude that a Si-PM-based gamma camera is promising for molecular imaging research.

  9. Scanning pupil approach to aspheric surface slope error tolerancing in head-up display optics

    NASA Astrophysics Data System (ADS)

    Sivokon, V. P.

    2015-09-01

    We present a novel approach to tolerancing slope errors of aspheric surfaces in relay optics of typical avionics head-up displays (HUD). In these systems, a beamlet entering the pilot eye occupies only a tiny fraction of HUD entrance pupil/eyebox with a typical diameter of 125mm. Consequently the beam footprint on any HUD optical surface is a small fraction of its clear aperture. This presents challenges to HUD tolerancing which is typically based on parallax (angular difference in line of sight between left and right eyes) analysis. Aspheric surfaces manufactured by sub-aperture grinding/polishing techniques add another source of error - surface slope error. This type of error not only degrades image quality of observed HUD symbology but also leads to its "waviness" and "floating" especially noticeable when a pilot moves his head within the HUD eyebox. The suggested approach allows aspheric surface slope error tolerancing that ensures an acceptable level of symbology "waviness". A narrow beamlet is traced from a pilot eye position backwards through the HUD optics until it hits the light source. Due to the small beamlet size, slope error of the aspheric surface acts primarily as an overall tilt/wedge that deviates the beam and causes it to shift. The slope error is acceptable when this shift is not resolved by a pilot eye. The beamlet is scanned over entire eyebox and field of view and the slope error tolerance is established for several zones in the aspheric surface clear aperture. The procedure is then repeated for each aspheric surface.

  10. Design of the RELAXin in acute heart failure study.

    PubMed

    Ponikowski, Piotr; Metra, Marco; Teerlink, John R; Unemori, Elaine; Felker, G Michael; Voors, Adriaan A; Filippatos, Gerasimos; Greenberg, Barry; Teichman, Sam L; Severin, Thomas; Mueller-Velten, Guenther; Cotter, Gad; Davison, Beth A

    2012-02-01

    Acute heart failure (AHF) remains a major public health burden with a high prevalence and poor prognosis. Relaxin is a naturally occurring peptide hormone that increases cardiac output, arterial compliance, and renal blood flow during pregnancy. The RELAX-AHF-1 study will evaluate the effect of RLX030 (recombinant form of human relaxin 2) on symptom relief and clinical outcomes in patients with AHF. The protocol includes a completed phase 2 234-patient dose-finding study (Pre-RELAX-AHF) and an ongoing phase 3 1,160-patient trial (RELAX-AHF-1). Patients with AHF and systolic blood pressure >125 mm Hg are randomized within 16 hours of presentation to a 48-hour IV infusion of RLX030 or placebo. The 30 μg/kg per day dose of RLX030 was chosen for RELAX-AHF-1 based on effects on dyspnea, clinical outcomes, and safety observed in Pre-RELAX-AHF. Primary efficacy end points in RELAX-AHF-1 are (1) the area under the curve of change of the dyspnea Visual Analog Scale from baseline through day 5 and (2) whether the patient reports moderately to markedly better dyspnea at 6, 12, and 24 hours. Secondary efficacy end points include days alive and out of the hospital through day 60 and cardiovascular death or rehospitalization for heart failure or renal failure through day 60. Patients will be followed up through day 180 for mortality. As of September 19, 2011, 978 patients have been enrolled. Pre-RELAX-AHF results suggested that infusion of RLX030 may accelerate dyspnea relief and improve prognosis in patients hospitalized with AHF. RELAX-AHF-1 will further evaluate these effects. Copyright © 2012 Mosby, Inc. All rights reserved.

  11. Potential long-term benefits of acute hypothermia after spinal cord injury: assessments with somatosensory-evoked potentials.

    PubMed

    Maybhate, Anil; Hu, Charles; Bazley, Faith A; Yu, Qilu; Thakor, Nitish V; Kerr, Candace L; All, Angelo H

    2012-02-01

    Neuroprotection by hypothermia has been an important research topic over last two decades. In animal models of spinal cord injury, the primary focus has been assessing the effects of hypothermia on behavioral and histologic outcomes. Although a few studies have investigated electrophysiological changes in descending motor pathways with motor-evoked potentials recorded during cooling, we report here hypothermia induced increased electrical conduction in the ascending spinal cord pathways with somatosensory-evoked potentials in injured rats. In our experiments, these effects lasted long after the acute hypothermia and were accompanied by potential long-term improvements in motor movement. Laboratory investigation. University medical school. Twenty-one female Lewis rats. Hypothermia. All animals underwent spinal cord contusion with the NYU-Impactor by a 12.5-mm weight drop at thoracic vertebra T8. A group (n = 10) was randomly assigned for a systemic 2-hr hypothermia episode (32 ± 0.5°C) initiated approximately 2.0 hrs postinjury. Eleven rats were controls with postinjury temperature maintained at 37 ± 0.5°C for 2 hrs. The two groups underwent preinjury, weekly postinjury (up to 4 wks) somatosensory-evoked potential recordings and standard motor behavioral tests (BBB). Three randomly selected rats from each group were euthanized for histologic analysis at postinjury day 3 and day 28. Compared with controls, the hypothermia group showed significantly higher postinjury somatosensory-evoked potential amplitudes with longer latencies. The BBB scores were also higher immediately after injury and 4 wks later in the hypothermia group. Importantly, specific changes in the Basso, Beattie, Bresnahan scores in the hypothermia group (not seen in controls) indicated regained functions critical for motor control. Histologic evaluations showed more tissue preservation in the hypothermia group. After spinal cord injury, early systemic hypothermia provided significant neuroprotection weeks after injury through improved sensory electrophysiological signals in rats. This was accompanied by higher motor behavioral scores and more spared tissue in acute and postacute periods after injury.

  12. SU-E-T-574: Fessiblity of Using the Calypso System for HDR Interstitial Catheter Reconstruction

    SciTech Connect

    Li, J S; Ma, C

    2014-06-01

    Purpose: It is always a challenge to reconstruct the interstitial catheter for high dose rate (HDR) brachytherapy on patient CT or MR images. This work aims to investigate the feasibility of using the Calypso system (Varian Medical, CA) for HDR catheter reconstruction utilizing its accuracy on tracking the electromagnetic transponder location. Methods: Experiment was done with a phantom that has a HDR interstitial catheter embedded inside. CT scan with a slice thickness of 1.25 mm was taken for this phantom with two Calypso beacon transponders in the catheter. The two transponders were connected with a wire. The Calypso system was used to record the beacon transponders’ location in real time when they were gently pulled out with the wire. The initial locations of the beacon transponders were used for registration with the CT image and the detected transponder locations were used for the catheter path reconstruction. The reconstructed catheter path was validated on the CT image. Results: The HDR interstitial catheter was successfully reconstructed based on the transponders’ coordinates recorded by the Calypso system in real time when the transponders were pulled in the catheter. After registration with the CT image, the shape and location of the reconstructed catheter are evaluated against the CT image and the result shows an accuracy of 2 mm anywhere in the Calypso detectable region which is within a 10 cm X 10 cm X 10 cm cubic box for the current system. Conclusion: It is feasible to use the Calypso system for HDR interstitial catheter reconstruction. The obstacle for its clinical usage is the size of the beacon transponder whose diameter is bigger than most of the interstitial catheters used in clinic. Developing smaller transponders and supporting software and hardware for this application is necessary before it can be adopted for clinical use.

  13. Use of an Acellular Regenerative Tissue Matrix Over Chronic Wounds

    PubMed Central

    Stacey, D. Heath

    2013-01-01

    Objectives: Bioengineered skin grafts, including acellular dermal matrices, may be effective in treating lower extremity and trunk wounds that are not responsive to traditional wound management. Acellular dermal wound matrix is derived from human acellular dermal wound matrix (HADWM) tissue and provides a scaffold that supports cellular repopulation and revascularization. The major structural components of the dermis are retained during processing, and a single application has been shown to help achieve wound closure. Methods: This patient case series examined the use of HADWM on lower extremity and trunk wounds in 11 patients (6 male and 5 female) with a mean age of 55 years (range: 31–83 years). Wounds were debrided 1 to 2 times, followed by placement of HADWM (range: 4–330 cm2) on wounds that varied from the dorsal surface of the foot, lower abdomen, and lower extremity to the Achilles flap. A nonadherent layer in conjunction with bacitracin was placed over HADWM. Negative pressure wound therapy (NPWT) was placed over the HADWM and initiated continuously at −125 mm Hg for 1 to 2 weeks. After the application of NPWT, HADWM was covered with various gauze dressings using mineral oil. Results: All patients completed their treatment successfully, and follow-up ranged from 1 week to 6 months. One patient experienced an infection, which resulted in partial graft loss that required replacement with HADWM and NPWT. No additional complications occurred in the other patients. Conclusions: This patient case series demonstrated successful use of HADWM and NPWT, which further supports published studies documenting HADWM success in chronic wounds. PMID:24324850

  14. Use of an acellular regenerative tissue matrix over chronic wounds.

    PubMed

    Stacey, D Heath

    2013-01-01

    Bioengineered skin grafts, including acellular dermal matrices, may be effective in treating lower extremity and trunk wounds that are not responsive to traditional wound management. Acellular dermal wound matrix is derived from human acellular dermal wound matrix (HADWM) tissue and provides a scaffold that supports cellular repopulation and revascularization. The major structural components of the dermis are retained during processing, and a single application has been shown to help achieve wound closure. This patient case series examined the use of HADWM on lower extremity and trunk wounds in 11 patients (6 male and 5 female) with a mean age of 55 years (range: 31-83 years). Wounds were debrided 1 to 2 times, followed by placement of HADWM (range: 4-330 cm(2)) on wounds that varied from the dorsal surface of the foot, lower abdomen, and lower extremity to the Achilles flap. A nonadherent layer in conjunction with bacitracin was placed over HADWM. Negative pressure wound therapy (NPWT) was placed over the HADWM and initiated continuously at -125 mm Hg for 1 to 2 weeks. After the application of NPWT, HADWM was covered with various gauze dressings using mineral oil. All patients completed their treatment successfully, and follow-up ranged from 1 week to 6 months. One patient experienced an infection, which resulted in partial graft loss that required replacement with HADWM and NPWT. No additional complications occurred in the other patients. This patient case series demonstrated successful use of HADWM and NPWT, which further supports published studies documenting HADWM success in chronic wounds.

  15. Design and Construction of a Gamma Reaction History Diagnostic for the National Ignition Facility

    SciTech Connect

    R.M. Malone, B.C. Cox, B.C. Frogget, M.I. Kaufman, T.W. Tunnell; H.W. Herrmann, S.C. Evans, J.M. Mack, C.S. Young; W. Stoeffl

    2009-06-05

    Gas Cherenkov detectors have been used to convert fusion gammas into photons to achieve gamma reaction history (GRH) measurements. These gas detectors include a converter, pressurized gas volume, relay optics, and a photon detector. A novel design for the National Ignition Facility (NIF) using 90º Off-Axis Parabolic mirrors efficiently collects signal from fusion gammas with 8-ps time dispersion.1 Fusion gammas are converted to Compton electrons, which generate broadband Cherenkov light (our response is from 250 to 700 nm) in a pressurized gas cell. This light is relayed into a high-speed detector using three parabolic mirrors. The detector optics collect light from a 125-mm-diameter by 600-mm-long interchangeable gas (CO2 or SF6) volume. Because light is collected from source locations throughout the gas volume, the detector is positioned at the stop position rather than at an image position. The stop diameter and its position are independent of the light-generation locations along the gas cell. This design incorporates a fixed time delay that allows the detector to recover from prompt radiation. Optical ray tracings demonstrate how light can be collected from different angled trajectories of the Compton electrons as they traverse the gas volume. A Monte Carlo model of the conversion process from gammas to Cherenkov photons is used to generate photon trajectories. The collection efficiencies for different gamma energies are evaluated. At NIF, a cluster of four channels will allow for increased dynamic range, as well as different gamma energy thresholds. This GRH design is compared to a gas Cherenkov detector that utilizes a Cassegrain reflector now used at the OMEGA laser facility. 1. R. M. Malone, H. W. Herrmann, W. Stoeffl, J. M. Mack, C. S. Young, “Gamma bang time/reaction history diagnostics for the National Ignition Facility using 90º off-axis parabolic mirrors,” Rev. Sci. Instrum. 79, 10E532 (2008).

  16. Immediate loading short implants inserted on low bone quantity for the rehabilitation of the edentulous maxilla using an All-on-4 design.

    PubMed

    Maló, P; de Araújo Nobre, M A; Lopes, A V; Rodrigues, R

    2015-08-01

    More studies evaluating the outcome of short-length dental implants in immediate loading are needed. To evaluate the use of short-length tapered implants in immediate loading for complete edentulous maxillae rehabilitations using an All-on-4 design. This retrospective clinical study included a cohort of 43 patients with 172 implants (74 short-length implants) inserted in low bone quantity. The patients were followed between 4 months and 6 years (average = 3 years). Outcome measures were implant survival, marginal bone remodelling, biological and mechanical complications. Two patients with four short-length implants were lost to follow-up during the first year. Three short and three long implants failed in four patients, rendering an overall cumulative survival rate implant and patient level, respectively, of 95.7% and 95.1% for short implants, 100% for regular implants and 96.6% and 95.2% for long implants. The average marginal bone remodelling at 1 and 3 years was 0.97 and 1.25 mm for the short implants, 0.82 and 0.87 mm for regular implants and 0.87 and 0.98 mm for long implants. Three patients presented 4 short-length implants with peri-implant pockets (3 implants in 2 patients were pseudo-pockets). Mechanical complications were registered in 13 patients (7 provisional prostheses fractures and 6 abutment screw loosening). All complications were treated successfully. Within the limitations of this clinical study, the short-term outcome of fixed prosthetic complete edentulous maxillae rehabilitations supported by short-length implants inserted in low bone quantity areas is viable. Long-term clinical studies are necessary for evaluating the outcome of these implants. © 2015 John Wiley & Sons Ltd.

  17. Rapid Diffusion-Weighted Magnetic Resonance Imaging of the Brain Without Susceptibility Artifacts: Single-Shot STEAM With Radial Undersampling and Iterative Reconstruction.

    PubMed

    Merrem, Andreas; Hofer, Sabine; Voit, Dirk; Merboldt, K-Dietmar; Klosowski, Jakob; Untenberger, Markus; Fleischhammer, Julius; Frahm, Jens

    2017-07-01

    The aim of this study was to develop a rapid diffusion-weighted (DW) magnetic resonance imaging (MRI) technique for whole-brain studies without susceptibility artifacts and measuring times below 3 minutes. The proposed method combines a DW spin-echo module with a single-shot stimulated echo acquisition mode MRI sequence. Previous deficiencies in image quality due to limited signal-to-noise ratio are compensated for (1) by radial undersampling to enhance the flip angle and thus the signal strength of stimulated echoes; (2) by defining the image reconstruction as a nonlinear inverse problem, which is solved by the iteratively regularized Gauss-Newton method; and (3) by denoising with use of a modified nonlocal means filter. The method was implemented on a 3 T MRI system (64-channel head coil, 80 mT · m gradients) and evaluated for 10 healthy subjects and 2 patients with an ischemic lesion and epidermoid cyst, respectively. High-quality mean DW images of the entire brain were obtained by acquiring 1 non-DW image and 6 DW images with different diffusion directions at b = 1000 s · mm. The achievable resolution for a total measuring time of 84 seconds was 1.5 mm in plane with a section thickness of 4 mm (55 sections). A measuring time of 168 seconds allowed for an in-plane resolution of 1.25 mm and a section thickness of 3 mm (54 sections). Apparent diffusion coefficient values were in agreement with literature data. The proposed method for DW MRI offers immunity against susceptibility problems, high spatial resolution, adequate signal-to-noise ratio and clinically feasible scan times of less than 3 minutes for whole-brain studies. More extended clinical trials require accelerated computation and online reconstruction.

  18. Adenosine 3',5-cyclic monophosphate phosphodiesterase activity in granulosa cells from Booroola x Romney ewes with and without the F gene.

    PubMed

    McNatty, K P; Heath, D A; Lun, S; Hudson, N L

    1989-02-01

    Granulosa cells from ovarian follicles (greater than or equal to 1 mm diameter) in Booroola ewes which are homozygous (FF) or heterozygous (F+) for the F gene have previously been shown to produce significantly more cAMP in response to FSH or LH than those from similar sized follicles in ewes without the F gene (++). The aim of these studies was to test whether these F gene-specific differences arose because of differences in cAMP-phosphodiesterase (cAMP-PDE) activity. In the first study using 1 mumol cAMP/l as substrate, no F gene-specific effects were noted in cAMP-PDE activity in granulosa cells from small (1-2.5 mm diameter, n = 4 per genotype) or large (greater than or equal to 3 mm diameter, n = 4 per genotype) follicles from FF, F+ or ++ ewes, despite F gene-specific effects in FSH (1 microgram/ml)- and LH (0.1 microgram/ml)-induced cAMP accumulation in these same cell preparations. The overall mean levels of cAMP-PDE across all genotypes in cells from small and large follicles were 0.47 +/- 0.04 (S.E.M., n = 12) and 0.28 +/- 0.03 pmol cAMP/10(6) cells per min respectively; the mean PDE activity in cells from small follicles was significantly (P less than 0.05) higher compared with that in cells from large follicles. In a second study, granulosa cells from each genotype were pooled over all follicle sizes (greater than or equal to 1 mm diameter, one pool per genotype) and the rates of cAMP hydrolysis tested over a range of substrate concentrations (0-16 mumol/l) but no gene-specific differences with respect to the Michaelis constant and maximum velocity were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Effects of supervised exercise on lipid profiles and blood pressure control in people with type 2 diabetes mellitus: a meta-analysis of randomized controlled trials.

    PubMed

    Hayashino, Yasuaki; Jackson, Jeffrey L; Fukumori, Norio; Nakamura, Fumiaki; Fukuhara, Shunichi

    2012-12-01

    Our study's purpose was to perform a systematic review to assess the effect of supervised exercise interventions on lipid profiles and blood pressure control. We searched electronic databases and selected studies that evaluated the effect of supervised exercise intervention on cardiovascular risk factors in adult people with type 2 diabetes. We used random effect models to derive weighted mean differences of exercise on lipid profiles and blood pressure control. Forty-two RCTs (2808 subjects) met inclusion criteria and are included in our meta-analysis. Structured exercise was associated with a change in systolic blood pressure (SBP) of -2.42 mmHg (95% CI, -4.39 to -0.45 mmHg), diastolic blood pressure (DBP) of -2.23 mmHg (95% CI, -3.21 to -1.25 mmHg), high-density lipoprotein cholesterol (HDL-C) of 0.04 mmol/L (95% CI, 0.02-0.07 mmol/L), and low-density lipoprotein cholesterol (LDL-C) of -0.16 mmol/L (95% CI, -0.30 to -0.01 mmol/L). Heterogeneity was partially explained by age, dietary co-intervention and the duration and intensity of the exercise. Supervised exercise is effective in improving blood pressure control, lowering LDL-C, and elevating HDL-C levels in people with diabetes. Physicians should recommend exercise for their adult patients with diabetes who can safely do so. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Treatment of denture-related stomatitis improves endothelial function assessed by flow-mediated vascular dilation

    PubMed Central

    Osmenda, Grzegorz; Maciąg, Joanna; Wilk, Grzegorz; Maciąg, Anna; Nowakowski, Daniel; Loster, Jolanta; Dembowska, Elżbieta; Robertson, Douglas; Guzik, Tomasz

    2016-01-01

    Introduction The presence of oral inflammation has recently been linked with the pathogenesis of cardiovascular diseases. While numerous studies have described links between periodontitis and endothelial dysfunction, little is known about the influence of denture-related stomatitis (DRS) on cardiovascular risk. Therefore, the aim of this study was to determine whether the treatment of DRS can lead to improvement of the clinical measures of vascular dysfunction. Material and methods The DRS patients were treated with a local oral antifungal agent for 3 weeks. Blood pressure, flow-mediated dilatation (FMD) and nitroglycerine-mediated vascular dilatation (NMD) were measured during three study visits: before treatment, one day and two months after conclusion of antifungal therapy. Results Flow-mediated dilatation measurements showed significant improvement of endothelial function 2 months after treatment (FMD median 5%, 95 CI: 3–8.3 vs. 11%, 95% CI: 8.8–14.4; p < 0.01), while there was no difference in control, endothelium-independent vasorelaxations (NMD; median = 15.3%, 95% CI: 10.8–19.3 vs. 12.7%, 95% CI: 10.6–15; p = 0.3). Other cardiovascular parameters such as systolic (median = 125 mm Hg; 95% CI: 116–129 vs. 120 mm Hg, 95% CI: 116–126; p = 0.1) as well as diastolic blood pressure and heart rate (median = 65.5 bpm, 95% CI: 56.7–77.7 vs. 71 bpm, 95% CI: 66.7–75; p = 0.5) did not change during or after the treatment. Conclusions Treatment of DRS is associated with improvement of endothelial function. Since endothelial dysfunction is known to precede the development of severe cardiovascular disorders such as atherosclerosis and hypertension, patients should be more carefully screened for DRS in general dental practice, and immediate DRS treatment should be advised. PMID:28144257

  1. SU-E-J-72: Geant4 Simulations of Spot-Scanned Proton Beam Treatment Plans

    SciTech Connect

    Kanehira, T; Sutherland, K; Matsuura, T; Umegaki, K; Shirato, H

    2014-06-01

    Purpose: To evaluate density inhomogeneities which can effect dose distributions for real-time image gated spot-scanning proton therapy (RGPT), a dose calculation system, using treatment planning system VQA (Hitachi Ltd., Tokyo) spot position data, was developed based on Geant4. Methods: A Geant4 application was developed to simulate spot-scanned proton beams at Hokkaido University Hospital. A CT scan (0.98 × 0.98 × 1.25 mm) was performed for prostate cancer treatment with three or four inserted gold markers (diameter 1.5 mm, volume 1.77 mm3) in or near the target tumor. The CT data was read into VQA. A spot scanning plan was generated and exported to text files, specifying the beam energy and position of each spot. The text files were converted and read into our Geant4-based software. The spot position was converted into steering magnet field strength (in Tesla) for our beam nozzle. Individual protons were tracked from the vacuum chamber, through the helium chamber, steering magnets, dose monitors, etc., in a straight, horizontal line. The patient CT data was converted into materials with variable density and placed in a parametrized volume at the isocenter. Gold fiducial markers were represented in the CT data by two adjacent voxels (volume 2.38 mm3). 600,000 proton histories were tracked for each target spot. As one beam contained about 1,000 spots, approximately 600 million histories were recorded for each beam on a blade server. Two plans were considered: two beam horizontal opposed (90 and 270 degree) and three beam (0, 90 and 270 degree). Results: We are able to convert spot scanning plans from VQA and simulate them with our Geant4-based code. Our system can be used to evaluate the effect of dose reduction caused by gold markers used for RGPT. Conclusion: Our Geant4 application is able to calculate dose distributions for spot scanned proton therapy.

  2. Histological observation of RGCs and optic nerve injury in acute ocular hypertension rats

    PubMed Central

    Li, Shuang; Fang, Jia-Hua; Jiang, Fa-Gang

    2010-01-01

    AIM To explore the injury of retinal ganglion cells (RGCs) and optic nerves in acute ocular hypertension (OHT) rats. METHODS We retrogradely labeled RGCs and optic nerves of Sprague-Dawley rats by injecting 20g/L fluorogold (FG) into bilateral superior colliculi. Twenty-four hours after the injection, the right eyes were performed physiological saline anterior chamber perfusion with intraocular pressure maintained at 100mmHg for 60 minutes, while the contralateral eyes were performed sham procedure as control group without elevation of the saline bottle. Retinal hematoxylin and eosin (HE) sections, retinal whole mounts and frozen sections were made 14 days later to observe the morphology and survival of RGCs. Frozen sections and transmission electron microscopy were utilized to investigate the histological manifestations of optic nerves at the same time. RESULTS A larger number of RGCs presented in control group. It had an average density of 1995±125/mm2 and distributed uniformly, while RGCs in OHT eyes reduced significantly to 1505±43/mm2 compared with control group (P<0.05). The optic nerves in control group showed stronger and more uniform fluorescence on the frozen sections, and the auxiliary fibers as well as myelin sheaths were in even and intact organization by transmission electron microscopy. However, exiguous fluorescence signals, vesicular dissociation and disintegration of myelin sheaths were found in OHT group. CONCLUSION The present study suggested that fluorogold retrograde tracing is a feasible, convenient method for quantitative and qualitative study of neuronal populations and axonal injury in acute ocular hypertension rats. PMID:22553581

  3. Fluorinated methacrylamide chitosan hydrogel systems as adaptable oxygen carriers for wound healing.

    PubMed

    Wijekoon, Asanka; Fountas-Davis, Natalie; Leipzig, Nic D

    2013-03-01

    In this study a series of novel, biocompatible hydrogels able to repeatedly takeup and deliver oxygen at beneficial levels have been developed by conjugating various perfluorocarbon (PFC) chains to methacrylamide chitosan via Schiff base nucleophilic substitution, followed by photopolymerization to form hydrogels. The synthesized fluorinated methacrylamide chitosan (MACF) hydrogels were confirmed by high resolution (19)F NMR. Synthesized MACF hydrogels were tested for their ability to takeup and then release oxygen for future use in dermal wound healing. Depending on the PFC substitution type maximum O(2) uptake was observed within 2-6h, followed by complete release to the surrounding environment (5% CO(2)) within 12-120h at oxygen partial pressures of 1-25mm Hg h(-1), providing outstanding system tuning for wound healing and regenerative medicine. MACFs with the most fluorines per substitution showed the greatest uptake and release of oxygen. Interestingly, adding PFC chains with a fluorinated aromatic group considerably enhanced oxygen uptake and extended release compared with a linear PFC chain with the same number of fluorine molecules. MACF hydrogels proved to be readily reloaded with oxygen once release was complete, and regeneration could be performed as long as the hydrogel was intact. Fibroblasts were cultured on MACFs and assays confirmed that materials containing more fluorines per substitution supported the most cells with the greatest metabolic activity. This result was true, even without oxygenation, suggesting PFC-facilitated oxygen diffusion from the culture medium. Finally, MACF gradient hydrogels were created, demonstrating that these materials can control oxygen levels on a spatial scale of millimeters and greatly enhance cellular proliferative and metabolic responses.

  4. Use of negative pressure wound therapy in the treatment of neonatal and pediatric wounds: a retrospective examination of clinical outcomes.

    PubMed

    Baharestani, Mona Mylene

    2007-06-01

    The clinical effectiveness of negative pressure wound therapy for the management of acute and chronic wounds is well documented in the adult population but information regarding its use in the pediatric population is limited. A retrospective, descriptive study was conducted to examine the clinical outcomes of using negative pressure wound therapy in the treatment of pediatric wounds. The medical records of 24 consecutive pediatric patients receiving negative pressure wound therapy were reviewed. Demographic data, wound etiology, time to closure, closure method, duration of negative pressure wound therapy, complications, dressing change frequency, dressing type used, and pressure settings were analyzed. All categorical variables in the dataset were summarized using frequency (count and percentages) and all continuous variables were summarized using median (minimum, maximum). The 24 pediatric patients (mean age 8.5 years [range 14 days to 18 years old]) had 24 wounds - 12 (50%) were infected at baseline. Sixteen patients had hypoalbuminemia and six had exposed hardware and bone in their wounds. Twenty-two wounds reached full closure in a median time of 10 days (range 2 to 45) following negative pressure wound therapy and flap closure (11), split-thickness skin graft (three), secondary (four), and primary (four) closure. Pressures used in this population ranged from 50 to 125 mm Hg and most wounds were covered with reticulated polyurethane foam. One patient developed a fistula during the course of negative pressure wound therapy. When coupled with appropriate systemic antibiotics, surgical debridement, and medical and nutritional optimization, in this population negative pressure wound therapy resulted in rapid granulation tissue and 92% successful wound closure. Future neonatal and pediatric negative pressure wound therapy usage registries and prospective studies are needed to provide a strong evidence base from which treatment decisions can be made in the management

  5. Contrast ratio of veneering and core ceramics as a function of thickness.

    PubMed

    Antonson, S A; Anusavice, K J

    2001-01-01

    The recent development of several dental ceramic products has raised questions concerning the relative translucency potential of these materials. The objective of this study was to test the hypothesis that the contrast ratio of dental core and veneering ceramics is a linear function of ceramic thickness. Four groups of disk-shaped core ceramic specimens and four groups of veneering ceramic specimens (15 mm in diameter and 0.70, 1.10, 1.25, or 1.50 mm in thickness) were prepared for analysis. Five disks were randomly assigned to each of the eight groups. Four core ceramics were selected for study: (1) tetrasilicic fluormica glass ceramic, (2) quadruple-chain silicate glass ceramic, (3) barium silicate glass ceramic, and (4) sintered alumina. The four veneering ceramics included two feldspathic body porcelains, one fine-grained veneering porcelain, and one ultralow-fusing porcelain. There were significant differences among the mean contrast ratio values of these materials. The most translucent group of the core materials was tetrasilicic fluormica glass ceramic, and the least translucent material was sintered alumina. The most translucent group among the veneering ceramics was one of the feldspathic ceramics (Ceramco), and the least translucent material for all thicknesses was the ultralow-fusing veneering ceramic (Duceram LFC). The mean contrast ratio values were significantly different at a thickness of 1.50 mm of the four core ceramic groups and among the four veneering ceramic groups. The results of this study indicate that the tetrasilicic fluormica glass ceramic is generally the most translucent core ceramic for thicknesses of 0.70, 1.10, and 1.25 mm, and Ceramco porcelain is the most translucent veneering ceramic. However, for a thickness of 1.50 mm, the quadruple-chain silicate glass ceramic was the most translucent core ceramic. The relationship between contrast ratio and thickness was linear for all ceramics except Vita VMK 68.

  6. [Manufacture of diamond blades via microsystem technology].

    PubMed

    Spraul, Christoph W; Ertl, Stephan; Strobel, Stefan; Gretzschel, Ralph; Schirmer, Enrico; Rösch, Rudolf; Lingenfelder, Christian; Lang, Gerhard K

    2003-04-01

    The application of diamond knives has steadily increased in ophthalmic surgery. However, the geometry of the blade, its thickness and the sharpness of the cutting edge are limited by the abrasive diamond polishing process, e. g. the crystalline morphology of the bulk material and the grinding powder used. A new generation of diamond blades is presented herewith allowing free choice of blade shape and thickness and possessing excellent sharpness due to a new polishing process. The new production method is based on a high-quality CVD (chemical vapour deposition) diamond film of some tenths of microns thickness, deposited on a silicon wafer as microchip technology. The mechanical properties of this synthetic diamond film are almost equal to those of a natural diamond and the surface of this film is mirror-like after deposition without requiring post-polishing. The shape of the blade can be freely defined and is transferred into the diamond film by a plasma polishing process adopted from microsystem technology. The new production method results in highly reproducible diamond blades. Concave blades and round shapes can now be realised without the restrictions of the conventional production process. The force-free fabrication method even allows realisation of miniaturized blades (e. g. width < 0.125 mm, thickness < 50 microm) far beyond the possibilities of conventional diamond blade production. Plasma polishing by means of gas atoms results in extreme sharpness with the cutting edge radius in the range of approx. 3 nm. Utilising microsystem technology we were able to manufacture reproducible artificial diamond blades. The new process offers for the first time surgeons a possibility of designing blades with a geometry close to their personal needs. Furthermore, the potential of facet-free ergonomically shaped diamond blades may stimulate further improvements towards novel surgical techniques.

  7. Distinct development of the cerebral cortex in platypus and echidna.

    PubMed

    Ashwell, Ken W S; Hardman, Craig D

    2012-01-01

    Both lineages of the modern monotremes have distinctive features in the cerebral cortex, but the developmental mechanisms that produce such different adult cortical architecture remain unknown. Similarly, nothing is known about the differences and/or similarities between monotreme and therian cortical development. We have used material from the Hill embryological collection to try to answer key questions concerning cortical development in monotremes. Our findings indicate that gyrencephaly begins to emerge in the echidna brain shortly before birth (crown-rump length 12.5 mm), whereas the cortex of the platypus remains lissencephalic throughout development. The cortices of both monotremes are very immature at the time of hatching, much like that seen in marsupials, and both have a subventricular zone (SubV) within both the striatum and pallium during post-hatching development. It is particularly striking that in the platypus, this region has an extension from the palliostriatal angle beneath the developing trigeminoreceptive part of the somatosensory cortex of the lateral cortex. The putative SubV beneath the trigeminal part of S1 appears to accommodate at least two distinct types of cell and many mitotic figures and (particularly in the platypus) appears to be traversed by large numbers of thalamocortical axons as these grow in. The association with putative thalamocortical fibres suggests that this region may also serve functions similar to the subplate zone of Eutheria. These findings suggest that cortical development in each monotreme follows distinct paths from at least the time of birth, consistent with a long period of independent and divergent cortical evolution.

  8. Design and evaluation of a novel subatmospheric pressure bioreactor for the preconditioning of tissue-engineered vascular constructs.

    PubMed

    Coakley, Daniel N; Shaikh, Faisal M; O'Sullivan, Kathleen; Kavanagh, Eamon G; Grace, Pierce A; McGloughlin, Tim M

    2016-02-01

    The pre-conditioning of tissue-engineered vascular scaffolds with mechanical stimuli is being recognised as an essential step in producing a functional vascular construct. In this study we design and evaluate a novel bioreactor, which exerts a mechanical strain on developing vascular scaffolds via subatmospheric pressure. We design and construct a bioreactor, which exerts subatmospheric pressure via a vacuum assisted closure unit. Vascular scaffolds seeded with human umbilical endothelial cells were evaluated for structural integrity, microbial contamination, cellular viability, von Willebrand factor (VWF) production, cell proliferation and morphology under a range of subatmospheric pressures (75-200mmHg). The bioreactor produced sustained subatmospheric pressures, which exerted a mechanical strain on the vascular scaffold. No microbial contamination was found during the study. The structural integrity of the vascular construct was maintained. There was no difference in cellular viability between control or subatmospheric pressure groups (p = 0.817). Cells continued to produce VWF under a range of subatmospheric pressures. Cells subjected to subatmospheric pressures of 125mmHg and 200mmHg exhibited higher levels of growth than cells in atmospheric pressure at 24 (p≤0.016) and 48 hour (p≤0.001). Negative pressure affected cellular morphology, which were more organised, elongated and expanded when exposed to subatmospheric pressure. We have constructed and validated a novel subatmospheric bioreactor. The bioreactor maintained a continuous subatmospheric pressure to the vascular scaffolds in a stable, sterile and constant environment. The bioreactor exerted a strain on the vascular sheets, which was shown to alter cellular morphology and enhance cellular proliferation.

  9. Does length of prostate biopsy cores have an impact on diagnosis of prostate cancer?

    PubMed Central

    Ergün, Müslüm; İslamoğlu, Ekrem; Yalçınkaya, Soner; Tokgöz, Hüsnü; Savaş, Murat

    2016-01-01

    Objective To investigate whether core length is a significant biopsy parameter in the detection of prostate cancer. Material and methods We retrospectively analyzed pathology reports of the specimens of 188 patients diagnosed with prostate cancer who had undergone initial transrectal ultrasound (TRUS) guided prostate biopsy, and compared biopsy core lengths of the patients with, and without prostate cancer. The biopsy specimens of prostate cancer patients were divided into 3 groups according to core length, and the data obtained were compared (Group 1; total core length <10 mm, Group 2; total core length 10 mm–19 mm, and Group 3; total core length >20 mm). Biopsy core lengths of the patients diagnosed as prostate cancer, and benign prostatic hyperplasia were compared, and a certain cut-off value for core length with optimal diagnostic sensitivity and specificity for prostate cancer was calculated. Results Mean age, PSA and total length of cores were 65.08±7.41 years, 9.82±6.34 ng/mL and 11.2±0.2 mm, respectively. Assessment of biopsy core lengths showed that cores with cancer (n=993, median length 12.5 mm) were significantly longer than benign cores (n=1185, median length=11.3 mm) (p<0.001). Core length analysis yielded 12 mm cores have an optimal sensitivity (41.9%) and specificity (62%) for detection of cancer (odds ratio: 1.08). Conclusion Biopsy core length is one of the most important parameter that determines the quality of biopsy and detection of prostate cancer. A median sample length of 12 mm is ideal lower limit for cancer detection, and biopsy procedures which yield shorter biopsy cores should be repeated. PMID:27635285

  10. Caffeine improves performance in double poling during acute exposure to 2,000-m altitude.

    PubMed

    Stadheim, H K; Nossum, E M; Olsen, R; Spencer, M; Jensen, J

    2015-12-15

    There is limited research on the physiological effects of caffeine (CAF) ingestion on exercise performance during acute hypoxia. The aim of the present study was therefore to test the effect of placebo (PLA) and CAF (4.5 mg/kg) on double poling (DP) performance during acute hypoxia. Thirteen male subelite cross-country skiers (V̇o2max 72.6 ± 5.68 ml·kg(-1)·min(-1)) were included. Performance was assessed as 1) an 8-km cross-country DP time-trial (C-PT), and 2) time until task failure at a set workload equal to ∼90% of DP V̇o2max. Testing was carried out in a hypobaric chamber, at 800 mbar (Pio2: ∼125 mmHg) corresponding to ∼2,000 m above sea level in a randomized double-blinded, placebo-controlled, cross-over design. CAF improved time to task failure from 6.10 ± 1.40 to 7.22 ± 1.30 min (P < 0.05) and velocity the first 4 km (P < 0.05) but not overall time usage for the 8-km C-PT. During submaximal exercise subjects reported lower pain in arms and rate of perceived exertion (RPE) following CAF ingestion. Throughout C-PTs similar RPE and pain was shown between treatments. However, higher heart rate was observed during the CAF 8 km (187 ± 7 vs. 185 ± 7; P < 0.05) and 90% C-PT (185 ± 7 vs. 181 ± 9) associated with increased ventilation, blood lactate, glucose, adrenaline, decreased pH, and bicarbonate. The present study demonstrates for the first time that CAF ingestion improves DP time to task failure although not consistently time trial performance during acute exposure to altitude. Mechanisms underpinning improvements seem related to reduced pain RPE and increased heart rate during CAF C-PTs.

  11. Validation of a HPLC method for the measurement of erythrocyte encapsulated thymidine phosphorylase (EE-TP) activity.

    PubMed

    Fairbanks, Lynette D; Levene, Michelle; Bax, Bridget E

    2013-03-25

    A sensitive and simple reverse-phase high performance liquid chromatographic (HPLC) assay has been validated for the determination of thymine as a measure of thymidine phosphorylase activity encapsulated in erythrocytes (EE-TP), a formulation which is under clinical development as an enzyme replacement therapy for the treatment of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Diluted erythrocyte lysates were incubated in 100mM sodium phosphate buffer and 10mM thymidine at 37°C for 10min and the reaction stopped with 40% trichloroacetic acid. Following centrifugation, the supernatant was washed with water saturated diethyl ether, and injected onto a Spherisorb C(18) column (125mm×4.6mm, 5μm), with a mobile phase (40mM ammonium acetate, 5mM tetrabutyl ammonium hydrogen sulphate, pH 2.70) delivered at a flow rate of 1.0ml/min and run time of 8min. Ultraviolet detection (UV) was employed at 254nm. The method was linear in the range of 5-500nmol/ml (r(2)=0.992), specific with intra- and inter-day precisions of <9.6 and accuracies within ±20%. Limits of detection and quantification were 1.2nmol/ml and 10nmol/ml, respectively. The method was applied to quantify thymidine phosphorylase activity in samples of in-process controls and batches of EE-TP manufactured for clinical use. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Characterization of shape and terminal velocity of tephra particles erupted during the 2002 eruption of Etna volcano, Italy

    NASA Astrophysics Data System (ADS)

    Coltelli, M.; Miraglia, L.; Scollo, S.

    2008-09-01

    In this paper, we present a complete morphological characterization of the ash particles erupted on 18 December 2002 from Etna volcano, Italy. The work is based on the acquisition and processing of bidimensional digital images carried out by scanning electron microscopy (SEM) to obtain shape parameters by image analysis. We measure aspect ratio (AR), form factor (FF), compactness (CC), and rectangularity (RT) of 2065 ash particles with size between 0.026 and 1.122 mm. We evaluate the variation of these parameters as a function of the grain-size. Ash particles with a diameter of <0.125 mm vary from mostly equant to very equant, ash particles between 0.125 and 0.250 mm have an intermediate shape, and particles with diameters >0.250 mm are subelongate. We find that, on average, particles with a diameter of <0.250 mm are subrounded, particles between 0.250 and 0.50 mm are subangular, and particles >0.50 mm are angular. Using this morphological analysis and an empirical relation between the drag coefficient ( C D) and Reynolds number ( R e) of Wilson and Huang (Earth Planet Sci Lett 44:311-324, 1979), we calculate the terminal settling velocities ( V WH). The comparisons between these velocities and those calculated with the formula of Kunii and Levenspiel ( Fluidization engineering. Wiley, New York, pp 97, 1969) ( V KL), which considers ash particles as spheres, show that V KL are in average 1.28 greater than V WH. Hence, we quantify the systematic error on the spatial distribution of the mass computed around the volcano carried out by tephra dispersal models when the particles are assumed to be spherical.

  13. System analysis of spatial frequency domain imaging for quantitative mapping of surgically resected breast tissues

    NASA Astrophysics Data System (ADS)

    Laughney, Ashley M.; Krishnaswamy, Venkataramanan; Rice, Tyler B.; Cuccia, David J.; Barth, Richard J.; Tromberg, Bruce J.; Paulsen, Keith D.; Pogue, Brian W.; Wells, Wendy A.

    2013-03-01

    The feasibility of spatial frequency domain imaging (SFDI) for breast surgical margin assessment was evaluated in tissue-simulating phantoms and in fully intact lumpectomy specimens at the time of surgery. Phantom data was evaluated according to contrast-detail resolution, quantitative accuracy and model-data goodness of fit, where optical parameters were estimated by minimizing the residual sum of squares between the measured modulation amplitude and its solutions, modeled according to diffusion and scaled-Monte Carlo simulations. In contrast-detail phantoms, a 1.25-mm-diameter surface inclusion was detectable for scattering contrast >28% a fraction of this scattering contrast (7%) was detectable for a 10 mm surface inclusion and at least 33% scattering contrast was detected up to 1.5 mm below the phantom surface, a probing depth relevant to breast surgical margin assessment. Recovered hemoglobin concentrations were insensitive to changes in scattering, except for overestimation at visible wavelengths for total hemoglobin concentrations <15 μM. The scattering amplitude increased linearly with scattering concentration, but the scattering slope depended on both the particle size and number density. Goodness of fit was comparable for the diffusion and scaled-Monte Carlo models of transport in spatially modulated, near-infrared reflectance acquired from 47 lumpectomy tissues, but recovered absorption parameters varied more linearly with expected hemoglobin concentration in liquid phantoms for the scaled-Monte Carlo forward model. SFDI could potentially reduce the high secondary excision rate associated with breast conserving surgery; its clinical translation further requires reduced image reconstruction time and smart inking strategies.

  14. Estimating movement and survival rates of a small saltwater fish using autonomous antenna receiver arrays and passive integrated transponder tags

    USGS Publications Warehouse

    Rudershausen, Paul J.; Buckel, Jeffery A.; Dubreuil, Todd; O'Donnell, Matthew J.; Hightower, Joseph E.; Poland, Steven J.; Letcher, Benjamin H.

    2014-01-01

    We evaluated the performance of small (12.5 mm long) passive integrated transponder (PIT) tags and custom detection antennas for obtaining fine-scale movement and demographic data of mummichog Fundulus heteroclitus in a salt marsh creek. Apparent survival and detection probability were estimated using a Cormack Jolly Seber (CJS) model fitted to detection data collected by an array of 3 vertical antennas from November 2010 to March 2011 and by a single horizontal antenna from April to August 2011. Movement of mummichogs was monitored during the period when the array of vertical antennas was used. Antenna performance was examined in situ using tags placed in wooden dowels (drones) and in live mummichogs. Of the 44 tagged fish, 42 were resighted over the 9 mo monitoring period. The in situ detection probabilities of the drone and live mummichogs were high (~80-100%) when the ambient water depth was less than ~0.8 m. Upstream and downstream movement of mummichogs was related to hourly water depth and direction of tidal current in a way that maximized time periods over which mummichogs utilized the intertidal vegetated marsh. Apparent survival was lower during periods of colder water temperatures in December 2010 and early January 2011 (median estimate of daily apparent survival = 0.979) than during other periods of the study (median estimate of daily apparent survival = 0.992). During late fall and winter, temperature had a positive effect on the CJS detection probability of a tagged mummichog, likely due to greater fish activity over warmer periods. During the spring and summer, this pattern reversed possibly due to mummichogs having reduced activity during the hottest periods. This study demonstrates the utility of PIT tags and continuously operating autonomous detection systems for tracking fish at fine temporal scales, and improving estimates of demographic parameters in salt marsh creeks that are difficult or impractical to sample with active fishing gear.

  15. Land subsidence monitoring and prediction in Beijing based on multi-sensor InSAR and improved Gray-Markov model

    NASA Astrophysics Data System (ADS)

    Ke, Y.; Deng, Z.; Gong, H.; Guo, L.; Li, X.

    2016-12-01

    Land subsidence induced by excessive groundwater withdrawal has posed a severe threat to city infrastructures, buildings and water and gas pipes, and has caused considerable economic loss. With rapid population increase and the corresponding rising demand for ground water, the land deformation rate has sped up. It was reported that by the end of 2010, over 65% (4281km2) of the plain area in Beijing has suffered ground settlement of over 50mm. Timely monitoring of land subsidence is a prerequisite for understanding of spatiotemporal evolution and the mechanism of the process. Prediction of future land subsidence development assists decision making for prevention of the hazard. In this study, we combined InSAR techniques with an improved Gray-Markov model (GMM) to predict the spatiotemporal trend of ground settlement in Beijing. First, ENVISAT ASAR data from 2003 to 2010 and Radarsat-2 data from 2010 to 2014 were used to monitor land subsidence during the recent 11 years by PS-InSAR technique. Three settlement bowls were demonstrated in the study area and located in Chaoyang, Changping, and Tongzhou districts. The maximum displacement rate reached around 125mm/year and the maximum cumulative deformation reached over 1.3m. For each PS pixels, we developed an improved GMM in order to predict the deformation trend in the next three years. GMM was improved in two aspects. First, we adapted GMM model based on metabolism principle by assigning newer information with higher priority. Second, we applied k-means method to automatically partition the states in Markov chain instead of manually assigning Markov intervals. By applying the improved GMM to PS pixels over the study area, the deformation maps from 2015 to 2017 were generated and it was found that the maximum cumulative deformation will reach 1.6m by the end of 2017.

  16. Accuracy in the diagnosis of vertical root fractures, external root resorptions, and root perforations using cone-beam computed tomography with different voxel sizes of acquisition

    PubMed Central

    Bragatto, Fernanda Paula; Iwaki Filho, Liogi; Kasuya, Amanda Vessoni Barbosa; Chicarelli, Mariliani; Queiroz, Alfredo Franco; Takeshita, Wilton Mitsunari; Iwaki, Lilian Cristina Vessoni

    2016-01-01

    Aim: The aim of this study is to assess the accuracy of images acquired with cone-beam computed tomography (CBCT) in the identification of three different root alterations. Materials and Methods: Forty human premolars were allocated to four experimental groups (n = 10): sound teeth (control), vertical root fracture (VRF), external root resorption (ERR), and root perforation (RP). After the root alterations had been produced, four teeth were randomly assembled into 10 macerated mandibles and submitted to CBCT. Images were acquired with five voxel sizes (0.125, 0.200, 0.250, 0.300, and 0.400 mm) and assessed by three experienced dental radiologists. Sensitivity, specificity, positive and negative predictive values, and the areas under the receiver operating characteristic curve (accuracy) were calculated. The accuracy of imaging in different voxel sizes was compared with Tukey exact binomial test (α=5%). Results: Accuracy with voxel sizes 0.125, 0.200, and 0.250 mm was significantly higher in the detection of ERRs and VRFs than voxel sizes 0.300 and 0.400 mm. No statistical difference was found in terms of accuracy among any of the studied voxel sizes in the identification of RPs. Conclusions: Voxel size 0.125 mm produced images with the best resolution without increasing radiation levels to the patient when compared to voxel sizes 0.200 and 0.250 mm. Voxel sizes 0.300 and 0.400 mm should be avoided in the identification of root alterations. PMID:27994322

  17. Negative-pressure wound therapy after fasciotomy reduces muscle-fiber regeneration in a pig model.

    PubMed

    Wilkin, Geoffrey; Khogali, Shiemaa; Garbedian, Shawn; Slagel, Bradley; Blais, Simon; Gofton, Wade; Liew, Allan; Renaud, Jean-Marc; Papp, Steven

    2014-08-20

    Negative-pressure wound therapy (NPWT) can improve fasciotomy wound closure, but its effects on skeletal muscle are largely unknown. The purpose of this study was to evaluate NPWT effects on skeletal muscle after fasciotomy for compartment syndrome in an animal model and to assess regional variability in muscle fiber regeneration. Compartment syndrome was induced in the hindlimb of twenty-two adult female pigs with use of a continuous intracompartmental serum-infusion model. Fasciotomy was performed after six hours, and animals were randomized to receive either wet-to-dry gauze dressings (control group) or NPWT dressings (-125 mm Hg, continuous suction) for seven days. Delayed primary wound closure was attempted at seven days, and the peroneus tertius was harvested for analysis seven days or twenty-one days after fasciotomy. Muscles were weighed, and hematoxylin and eosin-stained samples from four regions of the muscle (superficial central, deep central, lateral, and proximal) were mapped for different cellular morphologies. Muscle weight was greater in the affected limb at all time points with no difference between treatment groups. At seven days, only the deep central samples in the NPWT group had a significantly greater cross-sectional area containing normal fibers as compared with that found in the controls. By twenty-one days, the deep central, lateral, and proximal regions of the NPWT-treated muscles had a smaller cross-sectional area containing normal fiber morphology and a greater cross-sectional area containing only mononucleated cells as compared with the controls. NPWT did not decrease muscle weight. At twenty-one days, the extent of muscle fiber regeneration after fasciotomy for compartment syndrome was reduced in muscles treated with NPWT for seven days compared with the values in the control group treated with wet-to-dry gauze dressings. NPWT may be harmful to skeletal muscle after compartment syndrome requiring fasciotomy and local wound care

  18. Controlled pitch-adjustment of impeller blades for an intravascular blood pump.

    PubMed

    Throckmorton, Amy L; Sciolino, Michael G; Downs, Emily A; Saxman, Robert S; López-Isaza, Sergio; Moskowitz, William B

    2012-01-01

    Thousands of mechanical blood pumps are currently providing circulatory support, and the incidence of their use continues to increase each year. As the use of blood pumps becomes more pervasive in the treatment of those patients with congestive heart failure, critical advances in design features to address known limitations and the integration of novel technologies become more imperative. To advance the current state-of-the-art in blood pump design, this study investigates the inclusion of pitch-adjusting blade features in intravascular blood pumps as a means to increase energy transfer; an approach not explored to date. A flexible impeller prototype was constructed with a configuration to allow for a variable range of twisted blade geometries of 60-250°. Hydraulic experiments using a blood analog fluid were conducted to characterize the pressure-flow performance for each of these twisted positions. The flexible, twisted impeller was able to produce 1-25 mmHg for 0.5-4 L/min at rotational speeds of 5,000-8,000 RPM. For a given twisted position, the pressure rise was found to decrease as a function of increasing flow rate, as expected. Generally, a steady increase in the pressure rise was observed as a function of higher twisted degrees for a constant rotational speed. Higher rotational speeds for a specific twisted impeller configuration resulted in a more substantial pressure generation. The findings of this study support the continued exploration of this unique design approach in the development of intravascular blood pumps.

  19. Comparison between margin-growing algorithms in radiotherapy software environments.

    PubMed

    Smith, D W; Morgan, A M; Pooler, A M; Thwaites, D I

    2008-05-01

    Margin-growing algorithms are commonly used tools that are available within virtual simulation and treatment planning software. We report on the accuracy of the margin-growing algorithms available in six commercially available radiotherapy software environments. A phantom containing two differently sized spheres and two rods (one level and one inclined) was constructed and scanned by CT with 1.25 mm, 2.5 mm, 3.75 mm and 5 mm slice thicknesses. The objects were outlined on a GE Advantage Simulator, and the outlined volumes recorded. Images and structures were transferred to MasterPlan, Xio, Pinnacle, Eclipse and Prosoma, where imported volumes were recorded. The contours on each system were grown isotropically by 10 mm, 20 mm and 30 mm, and volumes for each grown contour were recorded. Transfer of structure sets created in GE Advantage Simulator to the other software environments showed that the reported volumes of the four structures differ on each system. Results showed no correlation between volume accuracy and slice thickness. In general, margin growth of up to 30 mm for the rods and spheres is shown to be consistent between systems to within 1.33 mm for all slice thicknesses. Slice thickness did not appear to influence the accuracy of margin growth. Although this work highlights apparent differences in the reported volumes grown from the same original structure sets, the significance of this aspect of the planning process needs to weighed against reported intra- and inter-clinician variability in contour definition. It is not unreasonable, however, to expect that software packages should at least be consistent in volume information provided to the user.

  20. Pulmonary airways tree segmentation from CT examinations using adaptive volume of interest

    NASA Astrophysics Data System (ADS)

    Park, Sang Cheol; Kim, Won Pil; Zheng, Bin; Leader, Joseph K.; Pu, Jiantao; Tan, Jun; Gur, David

    2009-02-01

    Airways tree segmentation is an important step in quantitatively assessing the severity of and changes in several lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, and cystic fibrosis. It can also be used in guiding bronchoscopy. The purpose of this study is to develop an automated scheme for segmenting the airways tree structure depicted on chest CT examinations. After lung volume segmentation, the scheme defines the first cylinder-like volume of interest (VOI) using a series of images depicting the trachea. The scheme then iteratively defines and adds subsequent VOIs using a region growing algorithm combined with adaptively determined thresholds in order to trace possible sections of airways located inside the combined VOI in question. The airway tree segmentation process is automatically terminated after the scheme assesses all defined VOIs in the iteratively assembled VOI list. In this preliminary study, ten CT examinations with 1.25mm section thickness and two different CT image reconstruction kernels ("bone" and "standard") were selected and used to test the proposed airways tree segmentation scheme. The experiment results showed that (1) adopting this approach affectively prevented the scheme from infiltrating into the parenchyma, (2) the proposed method reasonably accurately segmented the airways trees with lower false positive identification rate as compared with other previously reported schemes that are based on 2-D image segmentation and data analyses, and (3) the proposed adaptive, iterative threshold selection method for the region growing step in each identified VOI enables the scheme to segment the airways trees reliably to the 4th generation in this limited dataset with successful segmentation up to the 5th generation in a fraction of the airways tree branches.

  1. CT Pulmonary Findings in Healthy Older Adult Aspirators versus Nonaspirators

    PubMed Central

    Butler, Susan G.; Clark, Hollins; Baginski, Scott G.; Todd, J. Tee; Lintzenich, Catherine; Leng, Xiaoyan

    2013-01-01

    Objectives/Hypothesis In previous studies, we consistently found that approximately 30% of asymptomatic healthy older adults silently aspirated liquids during a flexible endoscopic evaluation of swallowing (FEES), and that their aspiration status was stable for the following year. However, no studies have systematically evaluated effects of silent aspiration on lung parenchyma and airways. We used computed tomography (CT) to compare lungs of healthy older adult aspirators versus nonaspirators. We hypothesized that CT images would show pulmonary differences in healthy older adult aspirators versus nonaspirators. Study Design Prospective study. Methods Fifty healthy older adults (25 aspirators and 25 nonaspirators) who participated in a previous FEES were randomly selected. CT scans were performed; on inspiration, lung views were taken at 1.25 mm and 2.5 mm windows; on expiration, lung views were taken at 2.5 mm. CT scans were reviewed by radiologists blinded to group assignment. Outcomes included bronchiectasis, bronchiolectasis, bronchial wall thickening, parenchymal band, fibrosis, air trapping, intraluminal airway debris, and tree-in-bud pattern. Results Chi-square analyses between aspirators and nonaspirators found no statistically significant differences between aspirators and nonaspirators for any outcomes (p > 0.05). Logistic regression analyses adjusted for smoking did not change the results. Conclusion(s) There were no differences in pulmonary CT findings between healthy older adult aspirators and nonaspirators. This study adds to the evidence that some aspiration may be within the range of normal for older adults, or at least does not contribute to a change in pulmonary appearance on CT images. PMID:23832617

  2. Thermomechanical responses of concrete members strengthened with cfrp sheets

    NASA Astrophysics Data System (ADS)

    Alqurashi, Abdulaziz

    Strengthening structural members means to be able to carry additional loads. Since, 1990s, a lot of materials and techniques have been established to not only increasing the capacity of member but also facing deterioration. Deterioration has become one of the worst highly maintenance cost. According to The ASCE, 27.1% of all bridges in the United States are not effectual. This is because the high traffic reflects negatively to structural members and cause deterioration of these members. This problem has been cost a lot of money. In addition, FRP has approved that it can increase the capacity of member and overcome some disadvantages such as deterioration. Therefore, CFRP sheet has become widely used. However, high temperatures affect the performance of externally bonded CFRP sheet negatively. Investigation should be carried out on relaxation and flexural performance of members under different temperatures. Therefore, this thesis focus on analyzing and investigating the performance of strengthened members exposed to elevated temperatures (25 to 175 °C). The experimental program was divided to two main parts. First, 144 strengthen concrete blocks 100mm X 150mm X 75mm has been exposed to elevated temperatures. These blocks have two main categories, which are different CFRP sheet width, and different CFRP sheet length. Different CFRP width has three types, which are type 0.25B (25mm x 100mm), type 0.5B (50mm x 100mm) and type 0.75B (75mm x 100mm). Also, Different CFRP length has three types, which are type L e (bonded area of 50 mm by 90mm), 1.25 Le (area of 50mm by 125mm) and type 1.5Le (50mm by 137 mm). Second, studying the performance of RC beams exposed to elevated temperatures.

  3. Taguchi Optimization of Cutting Parameters in Turning AISI 1020 MS with M2 HSS Tool

    NASA Astrophysics Data System (ADS)

    Sonowal, Dharindom; Sarma, Dhrupad; Bakul Barua, Parimal; Nath, Thuleswar

    2017-08-01

    In this paper the effect of three cutting parameters viz. Spindle speed, Feed and Depth of Cut on surface roughness of AISI 1020 mild steel bar in turning was investigated and optimized to obtain minimum surface roughness. All the experiments are conducted on HMT LB25 lathe machine using M2 HSS cutting tool. Ranges of parameters of interest have been decided through some preliminary experimentation (One Factor At a Time experiments). Finally a combined experiment has been carried out using Taguchi’s L27 Orthogonal Array (OA) to study the main effect and interaction effect of the all three parameters. The experimental results were analyzed with raw data ANOVA (Analysis of Variance) and S/N data (Signal to Noise ratio) ANOVA. Results show that Spindle speed, Feed and Depth of Cut have significant effects on both mean and variation of surface roughness in turning AISI 1020 mild steel. Mild two factors interactions are observed among the aforesaid factors with significant effects only on the mean of the output variable. From the Taguchi parameter optimization the optimum factor combination is found to be 630 rpm spindle speed, 0.05 mm/rev feed and 1.25 mm depth of cut with estimated surface roughness 2.358 ± 0.970 µm. A confirmatory experiment was conducted with the optimum factor combination to verify the results. In the confirmatory experiment the average value of surface roughness is found to be 2.408 µm which is well within the range (0.418 µm to 4.299 µm) predicted for confirmatory experiment.

  4. Eye-tracker-guided non-mechanical excimer laser assisted penetrating keratoplasty.

    PubMed

    Janunts, Edgar; Schirra, Frank; Szentmáry, Nora; Seitz, Berthold; Langenbucher, Achim

    2013-03-18

    The purpose of the study was to implement a new eye tracking mask which could be used to guide the laser beam in automated non-mechanical excimer laser assisted penetrating keratoplasty. A new trephination mask design with an elevated surface geometry has been proposed with a step formation between conical and flat interfaces. Two recipient masks of 7.5/8.0 mm have been manufactured and tested. The masks have outer diameter of 12.5 mm, step formation at 10.5 mm, and slope of conical surfaces 15°. Its functionality has been tested in different lateral positions and tilts on a planar surface, and pig eye experiments. After successful validation on porcine eyes, new masks have been produced and tested on two patients. The build-in eye tracking software of the MEL 70 was always able to capture the masks. It has been shown that the unwanted pigmentation/pattern induced by the laser pulses on the mask surface does not influence the eye-tracking efficiency. The masks could be tracked within the 18 × 14 mm lateral displacement and up to 12° tilt. Two patient cases are demonstrated. No complications were observed during the surgery, although it needs some attention for aligning the mask horizontally before trephination. Stability of eye tracking masks is emphasized by inducing on purpose movements of the patient head. Eye-tracking-guided penetrating keratoplasty was successfully applied in clinical practice, which enables robust tracking criteria within an extended range. It facilitates the automated trephination procedure of excimer laser-assisted penetrating keratoplasty.

  5. Beamline X29: a novel undulator source for X-ray crystallography.

    PubMed

    Shi, Wuxian; Robinson, Howard; Sullivan, Michael; Abel, Don; Toomey, John; Berman, Lonny E; Lynch, Don; Rosenbaum, Gerd; Rakowsky, George; Rock, Larry; Nolan, Bill; Shea-McCarthy, Grace; Schneider, Dieter; Johnson, Erik; Sweet, Robert M; Chance, Mark R

    2006-09-01

    A high-flux insertion device and beamline for macromolecular crystallography has been built at the National Synchrotron Light Source (NSLS) that employs a mini-gap undulator source developed by the NSLS. The mini-gap undulator at beamline X29 is a hybrid-magnet device of period 12.5 mm operating at proven gaps of 3.3-10 mm. The beamline provides hard X-rays for macromolecular crystallography experiments from the second and third harmonics over an energy range of 5-15 keV. The X-ray optics is designed to deliver intense and highly collimated X-rays. Horizontal focusing is achieved by a cryogenically cooled sagittally focusing double-crystal monochromator with approximately 4.1:1 demagnification. A vertical focusing mirror downstream of the monochromator is used for harmonic rejection and vertical focusing. The experimental station hosts an Area Detector Systems Quantum 315 CCD detector with 2.2 s readout time between exposures and Crystal Logic goniostat for crystal rotation and detector positioning. An auto-mounter crystal changer has been installed to facilitate the high-throughput data collection required by the major users, which includes structural genomics projects and the Macromolecular Crystallography Research Resource mail-in program. X29 is 10(3) times brighter than any existing bending-magnet beamline at NSLS with an actual flux of 2.5 x 10(11) photons s(-1) through a 0.12 mm square aperture at 11.271 keV.

  6. Feasibility of CT-based 3D anatomic mapping with a scanning-beam digital x-ray (SBDX) system

    NASA Astrophysics Data System (ADS)

    Slagowski, Jordan M.; Tomkowiak, Michael T.; Dunkerley, David A. P.; Speidel, Michael A.

    2015-03-01

    This study investigates the feasibility of obtaining CT-derived 3D surfaces from data provided by the scanning-beam digital x-ray (SBDX) system. Simulated SBDX short-scan acquisitions of a Shepp-Logan and a thorax phantom containing a high contrast spherical volume were generated. 3D reconstructions were performed using a penalized weighted least squares method with total variation regularization (PWLS-TV), as well as a more efficient variant employing gridding of projection data to parallel rays (gPWLS-TV). Voxel noise, edge blurring, and surface accuracy were compared to gridded filtered back projection (gFBP). PWLS reconstruction of a noise-free reduced-size Shepp-Logan phantom had 1.4% rRMSE. In noisy gPWLS-TV reconstructions of a reduced-size thorax phantom, 99% of points on the segmented sphere perimeter were within 0.33, 0.47, and 0.70 mm of the ground truth, respectively, for fluences comparable to imaging through 18.0, 27.2, and 34.6 cm acrylic. Surface accuracies of gFBP and gPWLS-TV were similar at high fluences, while gPWLS-TV offered improvement at the lowest fluence. The gPWLS-TV voxel noise was reduced by 60% relative to gFBP, on average. High-contrast linespread functions measured 1.25 mm and 0.96 mm (FWHM) for gPWLS-TV and gFBP. In a simulation of gated and truncated projection data from a full-sized thorax, gPWLS-TV reconstruction yielded segmented surface points which were within 1.41 mm of ground truth. Results support the feasibility of 3D surface segmentation with SBDX. Further investigation of artifacts caused by data truncation and patient motion is warranted.

  7. Versatile use of vacuum-assisted healing in fifty patients

    PubMed Central

    Al Fadhli, Ahmad; Alexander, George; Kanjoor, James Roy

    2009-01-01

    Context: Wound management can often be a challenging experience, especially in the presence of diabetes mellitus, vascular or immunological compromise. While no single technique can be considered by itself to be ideal, vacuum-assisted healing, which is a recent innovation, is fast becoming a necessary addition as adjuvant therapy to hasten wound healing. Aims: To determine the efficacy of vacuum-assisted healing. Settings and Design: Plastic surgery centre. Ministry of Health Hospital, Kuwait. Materials and Methods: Patients from Kuwait in a wide variety of clinical situations were chosen for study: Patients (n=50) were classified by diagnosis: Group 1: pressure sore- sacral (n= 3), trochanteric (n=6), ischial (n= 2); Group 2: ulcers (n= 11); Group 3: traumatic soft tissue wounds (n =15); Group 4: extensive tissue loss from the abdominal wall perineum, thigh and axilla (n =5); Group 5: sternal dehiscence wounds (n =4) and Group 6: wounds from flap necrosis (n =4). All wounds were subjected to vacuum by wall unit or portable unit, using pressure of 100-125 mm - continuous or intermittent. Closure of wounds, significant reduction in size and refusal by patient for continuation of vacuum-assisted closure therapy were end points of vacuum application. Results: Sixteen per cent of patients showed complete healing of the wound. Seventy per cent of patients showed 20-78% reduction in wound size. In 14% of patients treatment had to be discontinued. All patients showed improvement in granulation tissue and reduction in bacterial isolates and tissue oedema. Conclusions: The application of subatmospheric pressure or negative pressure promotes healing in a wide range of clinical settings and is an advanced wound healing therapy that can optimize patient care, promote rapid wound healing and help manage costs. It may be used in most instances in both hospital and community settings. PMID:20368850

  8. Fracture toughness of nine flowable resin composites.

    PubMed

    Bonilla, Esteban D; Yashar, Mahrokh; Caputo, Angelo A

    2003-03-01

    Flowable composite is used in a variety of clinical applications; however, the capacity of these materials to resist crack propagation is not well understood. The purpose of this investigation was to compare the resistance to crack propagation of 9 flowable composites as measured by the fracture toughness. The composites studied include AeliteFlo, Crystal Essence, Flow-it, FloRestore, Permaflo, Revolution, Tetric Flow, VersaFlo, and Wave. Ten specimens of each composite were formed with a brass mold with a 3-mm preformed notch. The final dimensions of each specimen were 2 x 4.2 x 20 mm. All specimens were light-polymerized to manufacturer specifications and stored in air for 24 hours. The fracture toughness value, K(IC) (MNm(-3/2)), for each specimen was measured by use of a 3-point bending mode and a single-edge notched beam at a crosshead speed of 0.125 mm/min until fracture. The data were analyzed statistically by use of 1-way analysis of variance, t tests (P<.05), and regression analysis. The flowable composites tested showed a spectrum of fracture toughness values ranging from 1.15 +/- 0.10 MNm(-3/2) for Wave to 1.65 +/- 0.13 MNm(-3/2) for Permaflo (significantly different, P<.05). The remaining materials formed 1 group with intermediate K(IC) values not different from each other (P>.05) but significantly different from Wave and Permaflo. Comparisons of fracture toughness to the filler content by volume of each composite revealed no correlation. This in vitro study concluded that there was no significant difference among 7 of the 9 composites tested in their resistance to fracture. Permaflo showed the greatest resistance to crack propagation. There was no correlation between the filler content by volume and the fracture toughness of these flowable composites.

  9. Endodontic Working Length Measurement Using Cone-beam Computed Tomographic Images Obtained at Different Voxel Sizes and Field of Views, Periapical Radiography, and Apex Locator: A Comparative Ex Vivo Study.

    PubMed

    Yılmaz, Funda; Kamburoğlu, Kıvanç; Şenel, Buğra

    2017-01-01

    The aim of this study was to evaluate the accuracy of working length determination by using an electronic apex locator, periapical radiography, and cone-beam computed tomographic (CBCT) imaging obtained at different voxel sizes and field of views (FOVs) in extracted human teeth. Thirty extracted human mandibular premolar teeth were used. The electronic working length measurements were performed by using an electronic apex locator (Root ZX; J Morita Corp, Kyoto, Japan). Five different image sets were obtained as follows: (1) CBCT imaging: 40 × 40 mm FOV, 0.080 mm(3) (FOV40); (2) CBCT imaging: 60 × 60 mm FOV, 0.125 mm(3) (FOV60); (3) CBCT imaging: 80 × 80 mm FOV, 0.160 mm(3) (FOV80); (4) CBCT imaging: 100 × 100 mm FOV, 0.250 mm(3) (FOV100); and (5) periapical digital radiography. Direct measurements performed with an electronic digital caliper were considered as the gold standard and compared with the electronic apex locator, CBCT, and periapical image measurements. Data were analyzed using a 2-way analysis of variance test. Significance level was set at P < .05. There was no significant difference between or within operators in intraoral radiographs (P > .05 and the Gage R&R value was <30%). There were significant differences between and within operators for CBCT images (P < .05 and Gage R&R value was >30%). There were significant differences in the methods in terms of mean differences from the gold standard (P < .05). This study showed that available CBCT scans with different FOVs can be used for working length measurement. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. Variability of repeated coronary artery calcium scoring and radiation Dose on 64- and 16-slice computed tomography by prospective electrocardiographically-triggered axial and retrospective electrocardiographically-gated spiral computed tomography: a phantom study.

    PubMed

    Horiguchi, Jun; Kiguchi, Masao; Fujioka, Chikako; Arie, Ryuichi; Shen, Yun; Sunasaka, Kenichi; Kitagawa, Toshiro; Yamamoto, Hideya; Ito, Katsuhide

    2008-08-01

    We sought to compare coronary artery calcium (CAC) scores, the variability and radiation doses on 64- and 16-slice computed tomography (CT) scanners by both prospective electrocardiographically (ECG)-triggered and retrospective ECG-gated scans. Coronary artery models (n = 3) with different plaque CT densities (approximately 240 Hounsfield units [HU], approximately 600 HU, and approximately 1000 HU) of four sizes (1, 3, 5, and 10 mm in length) on a cardiac phantom were scanned three times in five heart rate sequences. The tube current-time products were set to almost the same on all four protocols (32.7 mAs for 64-slice prospective and retrospective scans, 33.3 mAs for 16-slice prospective and retrospective scans). Slice thickness was set to 2.5 mm to keep the radiation dose low. Overlapping reconstruction with a 1.25-mm increment was applied on the retrospective ECG-gated scan. The CAC scores were not different between the four protocols (one-factor analysis of variance: Agatston, P = .32; volume, P = .19; and mass, P = .09). Two-factor factorial analysis of variance test revealed that the interscan variability was different between protocols (P < .01) and scoring algorithms (P < .01). The average variability of Agatston/volume/mass scoring and effective doses were as follows: 64-slice prospective scan: 16%/15%/11% and 0.5 mSv; 64-slice retrospective scan: 11%/11%/8% and 3.7 mSv; 16-slice prospective scan: 20%/18%/13% and 0.6 mSv; and 16-slice retrospective scan: 16%/15%/11% and 2.9 to 3.5 mSv (depending on the pitch). Retrospective ECG-gated 64-slice CT showed the lowest variability. Prospective ECG-triggered 64-slice CT, with low radiation dose, shows low variability on CAC scoring comparable to retrospective ECG-gated 16-slice CT.

  11. Challenges in Modeling Debris-Flow Initiation during the Exceptional September 2013 Northern Colorado Front Range Rainstorm

    NASA Astrophysics Data System (ADS)

    Baum, R. L.; Coe, J. A.; Godt, J.; Kean, J. W.

    2014-12-01

    Heavy rainfall during 9 - 13 September 2013 induced about 1100 debris flows in the foothills and mountains of the northern Colorado Front Range. Eye-witness accounts and fire-department records put the times of greatest landslide activity during the times of heaviest rainfall on September 12 - 13. Antecedent soil moisture was relatively low, particularly at elevations below 2250 m where many of the debris flows occurred, based on 45 - 125 mm of summer precipitation and absence of rainfall for about 2 weeks before the storm. Mapping from post-event imagery and field observations indicated that most debris flows initiated as small, shallow landslides. These landslides typically formed in colluvium that consisted of angular clasts in a sandy or silty matrix, depending on the nature of the parent bedrock. Weathered bedrock was partially exposed in the basal surfaces of many of the shallow source areas at depths ranging from 0.2 to 5 m, and source areas commonly occupied less than 500 m2. Although 49% of the source areas occurred in swales and 3 % in channels, where convergent flow might have contributed to pore-pressure build up during the rainfall, 48% of the source areas occurred on open slopes. Upslope contributing areas of most landslides (58%) were small (< 1000 m2) and 78% of the slides occurred on south-facing slopes (90°≤ aspect ≤270°). These observations pose challenges for modeling initiation of the debris flows. Effects of variable soil depth and properties, vegetation, and rainfall must be examined to explain the dominance of debris flows on south-facing slopes. Accounting for the small sizes and mixed swale and open-slope settings of source areas demands new approaches for resolving soil-depth and physical-properties variability. The low-moisture initial conditions require consideration of unsaturated zone effects. Ongoing fieldwork and computational modeling are aimed at addressing these challenges related to initiation of the September 2013 debris

  12. Novel combination strategies to repair the injured mammalian spinal cord.

    PubMed

    Bunge, Mary Bartlett

    2008-01-01

    Due to the varied and numerous changes in spinal cord tissue following injury, successful treatment for repair may involve strategies combining neuroprotection (pharmacological prevention of some of the damaging intracellular cascades that lead to secondary tissue loss), axonal regeneration promotion (cell transplantation, genetic engineering to increase growth factors, neutralization of inhibitory factors, reduction in scar formation), and rehabilitation. Our goal has been to find effective combination strategies to improve outcome after injury to the adult rat thoracic spinal cord. Combination interventions tested have been implantation of Schwann cells (SCs) plus neuroprotective agents and growth factors administered in various ways, olfactory ensheathing cell (OEC) implantation, chondroitinase addition, or elevation of cyclic AMP. The most efficacious strategy in our hands for the acute complete transection/SC bridge model, including improvement in locomotion [Basso, Beattie, Bresnahan Scale (BBB)], is the combination of SCs, OECs, and chondroitinase administration (BBB 2.1 vs 6.6, 3 times more myelinated axons in the SC bridge, increased serotonergic axons in the bridge and beyond, and significant correlation between the number of bridge myelinated axons and functional improvement). We found the most successful combination strategy for a subacute spinal cord contusion injury (12.5-mm, 10-g weight, MASCIS impactor) to be SCs and elevation of cyclic AMP (BBB 10.4 vs 15, significant increases in white matter sparing, in myelinated axons in the implant, and in responding reticular formation and red and raphe nuclei, and a significant correlation between the number of serotonergic fibers and improvement in locomotion). Thus, in two injury paradigms, these combination strategies as well as others studied in our laboratory have been found to be more effective than SCs alone and suggest ways in which clinical application may be developed.

  13. Impact of Rainfall Intensity and Groundwater Table and of Slope on Non-point Source Pollution Reduction Mechanism of Vegetative Filter Strips: Laboratory Experimental and VFSMOD Modeling

    NASA Astrophysics Data System (ADS)

    Li, R.; Kuo, Y. M.

    2016-12-01

    Riparian vegetative filter strips (VFS) has been used as a best management practices (BMPs) through a series of physical, chemical and biochemical processes to protect water bodies from human influence. This research attempted to determine the performance of VFS against laboratory mesoscale data in various conditions with rainfall intensities (25-125 mm/h), slopes (0-20°) and depths of groundwater table (0-50 cm below ground surface), and then to evaluate the VFS trapping mechanisms after coupling the VFS overland flow and VFSMOD. A controlled laboratory soil chamber (200 cm long, 100 cm wide and 60 cm deep) was used to simulate a VFS with planting ryegrass on sandy loam soils. Results showed that groundwater tables significantly affected the infiltration (r2 = 0.91), which can also potentially influence the pollution trapping mechanisms. The concentration reduction of as much as 96% for total suspended sediment (TSS), 92% for total nitrogen (TN), and 90% for total phosphorous (TP) when the slope of VFS was 2%, while the reduction efficiency had downward trends with the slope increased. The trapping efficiency of TSS decreased from 70% to 40% with the rainfall intensity increased from 25 mm/h to 70 mm/h, which also showed more severe soil erosion comparing to the same intensity runoff. Based on predicted and measured results, the model performance was considered effective with greater than 86.0% probability across all scenarios. Therefore, the combination of VFS and VFSMOD was able to successfully capture the runoff dynamics through VFS to provide a reference for BMPs controlling non-point source pollution.

  14. [Stability effect of the suprajacent vertebrae after fixation in spondylolisthesis. Comparative study of two systems].

    PubMed

    Rosales-Olivares, Luis Miguel; Ruiz-Morfín, Aarón; Miramontes-Martínez, Víctor Paul; Alpízar-Aguirre, Armando; Reyes-Sánchez, Alejandro Antonio

    2006-01-01

    This study was undertaken to evaluate vertebral stability after two different types of fusion fixation (rigid and semirigid) in spondylolisthesis. Ambispective study of a dynamic cohort constituted by 42 patients that underwent surgery between 1990 and 2000 for a spondilolistesis treatment. According to the fixing type, they were divided into two follow-up groups: to group 1, plate INO (semirigid system) was placed + posterolateral fusion (PLF), 20 cases; to group 2, plate INO was installed + intersomatic screw + PLF, 22 cases. Both groups achieved better listhesis, reduced pain according to Oswestry and SF36 Index (p <0.05), and less intervertebral height was lost. Group 1 lost the least amount (-0.61 mm) of invertebral height if grades of presurgical listhesis were 1-2, and higher (-2.0 mm) if grades of presurgical listhesis were 3-4. Inversely, group 2 lost the least (0.50 mm) if grade of listhesis was 3 or 4, and higher (-1.25 mm) if grades of listhesis were 1-2. From 4 to 7 years, in group 2 there was altered bending of 5.8 degrees to 8.3 degrees (p = 0.05), a significant difference from group 1. Group 2 showed higher flexion grades (p = 0.01) at 4-7 years postoperatively and a significant reduction in EVA (p = 0.04) at more than 7 years. The remaining patients showed no significant differences between groups. But loss of intervertebral height was higher in group 2 (-1.18 mm) than group 1 (-0.75 mm). Plate INO + PLF favored flexibility and reduced loss of intervertebral height in grades 1-2 of presurgical listhesis, INO + screw + PLF showed reduced listhesis and decrease of height lost in grades 3-4 of presurgical listhesis. We recommended the use of INO + PLF in grades 1-2 of presurgical listhesis and INO + screw + PLF in grades 3-4 of listhesis presurgically.

  15. Intervening to improve health indicators among Australian farm families.

    PubMed

    Blackburn, Justin; Brumby, Susan; Willder, Stuart; McKnight, Robert

    2009-01-01

    The Sustainable Farm Families project (http://www.sustainablefarmfamilies.org.au/) was a 3-year demonstration and education project designed to influence farmer behavior with respect to family health and well-being among cropping and grazing farmers in Victoria, New South Wales, and South Australia, Australia. The project was conducted by the Western District Health Service, Hamilton, Australia, in partnership with farmers; Farm Management 500 (peer discussion group); the Victorian Farmers Federation; Royal Melbourne Institute of Technology; and Land Connect. During the 3 years of the project, 128 farmers-men (70) and women (58)-were enrolled. The project utilized a combination of small group workshops, individualized health action plans, and health education opportunities to encourage farm safety and health behavior changes and to elicit sustained improvements in the following health indicators: body mass index (BMI), total cholesterol, fasting blood glucose, and blood pressure. Mean changes in these health indicators were analyzed using repeated measures analysis of variance (ANOVA) and McNemar's test compared the proportion of individuals with elevated indicators. Among participants with elevated values at baseline, the following average reductions were observed: BMI 0.44 kg/m(2) (p = .0034), total cholesterol 48.7 mg/dl (p < .0001), blood glucose 10.1 mg/dl (p = .0016), systolic blood pressure 12.5 mm Hg (p < .0001), and diastolic blood pressure 5.0 mm Hg (p = .0007). The proportion of participants with elevated total cholesterol at baseline decreased after 24 months (p < .001). Such findings suggest that proactive intervention by farmer associations, rural health services, and government agencies may be an effective vehicle for promoting voluntary farm safety and health behavior change while empowering farm families to achieve measurable reductions in important health risk factors.

  16. Design and implementation of non-linear image processing functions for CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Musa, Purnawarman; Sudiro, Sunny A.; Wibowo, Eri P.; Harmanto, Suryadi; Paindavoine, Michel

    2012-11-01

    Today, solid state image sensors are used in many applications like in mobile phones, video surveillance systems, embedded medical imaging and industrial vision systems. These image sensors require the integration in the focal plane (or near the focal plane) of complex image processing algorithms. Such devices must meet the constraints related to the quality of acquired images, speed and performance of embedded processing, as well as low power consumption. To achieve these objectives, low-level analog processing allows extracting the useful information in the scene directly. For example, edge detection step followed by a local maxima extraction will facilitate the high-level processing like objects pattern recognition in a visual scene. Our goal was to design an intelligent image sensor prototype achieving high-speed image acquisition and non-linear image processing (like local minima and maxima calculations). For this purpose, we present in this article the design and test of a 64×64 pixels image sensor built in a standard CMOS Technology 0.35 μm including non-linear image processing. The architecture of our sensor, named nLiRIC (non-Linear Rapid Image Capture), is based on the implementation of an analog Minima/Maxima Unit. This MMU calculates the minimum and maximum values (non-linear functions), in real time, in a 2×2 pixels neighbourhood. Each MMU needs 52 transistors and the pitch of one pixel is 40×40 mu m. The total area of the 64×64 pixels is 12.5mm2. Our tests have shown the validity of the main functions of our new image sensor like fast image acquisition (10K frames per second), minima/maxima calculations in less then one ms.

  17. Optical coherence tomography evaluation of posterior capsule opacification related to intraocular lens design.

    PubMed

    Moreno-Montañés, Javier; Alvarez, Aurora; Bes-Rastrollo, Maira; García-Layana, Alfredo

    2008-04-01

    To evaluate posterior capsule opacification (PCO) and the impact of different intraocular lens (IOL) models on PCO characteristics using optical coherence tomography (OCT). Eighty-three eyes with PCO (fibrosis or pearl type) and 32 pseudophakic eyes without PCO were included. Horizontal 3.0 mm long OCT scans of the posterior capsule were obtained. Measurements and means of the peak posterior capsule intensity (PCI) and posterior capsule thickness (PCT) (distance between 2 spikes at posterior capsule) at 3 scan points were recorded. The PCI and PCT were compared with best corrected visual acuity (BCVA) and IOL data. The PCT was high for IOLs with a rounded edge (P = .001) and with poly(methyl methacrylate) (PMMA) IOLs (P<.001). If the IOL optic was concave-convex, the PCT was higher than if the optic was biconvex (P = .001). The PCT of hydrophilic acrylic IOLs was higher than of hydrophobic acrylic IOLs (P = .04). Multivariate analysis of PCT showed that PMMA was the only factor statistically associated with PCT (P = .02). The worse logMAR BCVA correlated significantly with a higher PCT value (P<.001) but not with PCI (P = .42). An IOL size of 12.5 mm was related to fibrosis-type PCO (odds ratio, 3.14; P = .04). The PCT was most affected by IOL characteristics. Poly(methyl methacrylate) IOLs and IOLs with rounded edges were associated with higher PCT. Hydrophilic acrylic IOLs were associated with greater PCT than hydrophobic IOLs. Posterior capsule thickness was a factor in decreased BCVA.

  18. A three-dimensional culture system using alginate hydrogel prolongs hatched cattle embryo development in vitro.

    PubMed

    Zhao, Shuan; Liu, Zhen-Xing; Gao, Hui; Wu, Yi; Fang, Yuan; Wu, Shuai-Shuai; Li, Ming-Jie; Bai, Jia-Hua; Liu, Yan; Evans, Alexander; Zeng, Shen-Ming

    2015-07-15

    No successful method exists to maintain the three-dimensional architecture of hatched embryos in vitro. Alginate, a linear polysaccharide derived from brown algae, has characteristics that make it an ideal material as a three-dimensional (3D) extracellular matrix for in vitro cell, tissue, or embryo culture. In this study, alginate hydrogel was used for IVC of posthatched bovine embryos to observe their development under the 3D system. In vitro-fertilized and parthenogenetically activated posthatched bovine blastocysts were cultured in an alginate encapsulation culture system (AECS), an alginate overlay culture system (AOCS), or control culture system. After 18 days of culture, the survival rate of embryos cultured in AECS was higher than that in the control group (P < 0.05), and the embryos were expanded and elongated in AECS with the maximal length of 1.125 mm. When the AECS shrinking embryos were taken out of the alginate beads on Day 18 and cultured in the normal culture system, 9.09% of them attached to the bottoms of the plastic wells and grew rapidly, with the largest area of an attached embryo being 66.00 mm(2) on Day 32. The embryos cultured in AOCS developed monovesicular or multivesicular morphologies. Total cell number of the embryos cultured in AECS on Day 19 was significantly higher than that of embryos on Day 8. Additionally, AECS and AOCS supported differentiation of the embryonic cells. Binuclear cells were visible in Day-26 adherent embryos, and the messenger RNA expression patterns of Cdx2 and Oct4 in AOCS-cultured embryos were similar to those in vivo embryos, whereas IFNT and ISG15 messenger RNA were still expressed in Day-26 and Day-32 prolong-cultured embryos. In conclusion, AECS and AOCS did support cell proliferation, elongation, and differentiation of hatched bovine embryos during prolonged IVC. The culture system will be useful to further investigate the molecular mechanisms controlling ruminant embryo elongation and implantation.

  19. Simultaneous online SPE-HPLC-MS/MS analysis of docetaxel, temsirolimus and sirolimus in whole blood and human plasma.

    PubMed

    Navarrete, Alicia; Martínez-Alcázar, M Paz; Durán, Ignacio; Calvo, Emiliano; Valenzuela, Belén; Barbas, Coral; García, Antonia

    2013-03-15

    Docetaxel and temsirolimus are some of the most used drugs in a wide range of solid tumors. In preclinical studies, mTOR inhibitors such as temsirolimus have demonstrated synergistic cytotoxic effects with taxanes providing the rationale for combination studies. These anticancer agents exhibit a narrow therapeutic concentration range and due to their high inter- and intra-individual pharmacokinetic variability, therapeutic dose monitoring by highly sensitive methods as LC-MS/MS are important for clinical research. Therefore, the aim of this study was to develop and validate a sensitive, fast and convenient method for the simultaneous identification and quantification of docetaxel, temsirolimus and its main metabolite, sirolimus, using paclitaxel, another anticancer drug, as the internal standard. These analytes were quantified by an integrated online solid phase extraction-high performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) system. Separation was performed on a Zorbax eclipse XDB-C8 (150mm×4.6mm, 5μm) column. The mass spectrometer tandem quadruple detector was equipped with jet stream electrospray ionization, monitored in multiple reactions monitoring (MRM) and operated in positive mode. A combination of protein precipitation with methanol/zinc sulphate (70:30) (v/v) and online SPE using a Zorbax eclipse plus C8 (12.5mm×4.6mm, 5μm) cartridge was used to extract the compounds. This method allows the use of the same reagents, sample treatment and analytical technique independently of whether the samples are whole blood or plasma. The method has been successfully validated and applied to real samples. It is a suitable method for dose adjustment and for evaluating potential drug interactions during combined treatments.

  20. Negative Pressure Wound Therapy of Chronically Infected Wounds Using 1% Acetic Acid Irrigation

    PubMed Central

    Lee, Byeong Ho; Lee, Hye Kyung; Kim, Hyoung Suk; Moon, Min Seon; Suh, In Suck

    2015-01-01

    Background Negative-pressure wound therapy (NPWT) induces angiogenesis and collagen synthesis to promote tissue healing. Although acetic acid soaks normalize alkali wound conditions to raise tissue oxygen saturation and deconstruct the biofilms of chronic wounds, frequent dressing changes are required. Methods Combined use of NPWT and acetic acid irrigation was assessed in the treatment of chronic wounds, instilling acetic acid solution (1%) beneath polyurethane membranes twice daily for three weeks under continuous pressure (125 mm Hg). Clinical photographs, pH levels, cultures, and debrided fragments of wounds were obtained pre- and posttreatment. Tissue immunostaining (CD31, Ki-67, and CD45) and reverse transcription-polymerase chain reaction (vascular endothelial growth factor [VEGF], vascular endothelial growth factor receptor [VEGFR]; procollagen; hypoxia-inducible factor 1 alpha [HIF-1-alpha]; matrix metalloproteinase [MMP]-1,-3,-9; and tissue inhibitor of metalloproteinase [TIMP]) were also performed. Results Wound sizes tended to diminish with the combined therapy, accompanied by drops in wound pH (weakly acidic or neutral) and less evidence of infection. CD31 and Ki-67 immunostaining increased (P<0.05) post-treatment, as did the levels of VEGFR, procollagen, and MMP-1 (P<0.05), whereas the VEGF, HIF-1-alpha, and MMP-9/TIMP levels declined (P<0.05). Conclusions By combining acetic acid irrigation with negative-pressure dressings, both the pH and the size of chronic wounds can be reduced and infections be controlled. This approach may enhance angiogenesis and collagen synthesis in wounds, restoring the extracellular matrix. PMID:25606491

  1. Nd:Yag goniopuncture after deep sclerectomy with collagen implant.

    PubMed

    Mermoud, A; Karlen, M E; Schnyder, C C; Sickenberg, M; Chiou, A G; Hédiguer, S E; Sanchez, E

    1999-02-01

    To study the need, the safety and the success rate of Nd:Yag goniopuncture in eyes that underwent deep sclerectomy with collagen implant. The first 100 patients that underwent deep sclerectomy with collagen implant were prospectively followed. Deep sclerectomy with collagen implant is a non-penetrating filtering surgery which allows filtration of aqueous from the anterior chamber to the subconjunctival space through a remaining trabeculo-Descemet's membrane without opening the anterior chamber. Goniopunctures with Nd:Yag laser were performed at the site of surgery when the filtration through the trabeculo-Descemet's membrane was considered to be insufficient with elevated intraocular pressure. The laser treatment was performed using a Lasag 15 gonioscopy contact lens (CGA1). Goniopunctures were performed using the free-running Q-switched mode with an energy ranging from 2 to 4 mJ. Of 100 patients who underwent deep sclerectomy with collagen implant, goniopunctures with Nd:Yag laser were performed in 41 patients (41%). The mean time between deep sclerectomy with collagen implant and goniopuncture was 9.9 months +/-1.2 months (+/-SE). The mean IOP before laser treatment was 22.2 mm +/-7.0 mm Hg and decreased to 12.5 mm +/-5.8 mm Hg immediately after laser treatment and remained stable for the next 2 years of follow-up. The immediate success rate of goniopuncture was 83%. Choroidal detachment occurred in two patients (5%). Nd:Yag goniopuncture is an efficient and safe treatment for low filtration through the trabeculo-Descemet's membrane after deep sclerectomy with collagen implant.

  2. Microwave treatment of eight seconds protects cells of Isatis indigotica from enhanced UV-B radiation lesions.

    PubMed

    Chen, Yi-Ping

    2006-01-01

    To determine the role of microwaves in the stress resistance of plants to enhanced ultraviolet-B (UV-B) radiation, Isatis indigotica Fort. seeds were subjected to microwave radiation for 8 s (wavelength 125 mm, power density 1.26 mW mm(-2), 2450 MHz). Afterwards they were cultivated in plastic pots in an artificial-glass greenhouse maintained at 25 degrees C, 70% relative humidity, and 400 micromol mol(-1) CO2, under visible-light conditions of 1500 micromol m(-2) s(-1) for 8 h day(-1). When the seedlings were 10 days old, they were subjected to 10.08 kJ m(-2) UV-B (PAR: 220 micromol m(-2) s(-1)) radiation for 8 days. Changes in a number of physiological and biochemical characteristics and in the thermal decomposition enthalpy of biomass were measured and used as indicators of the protective capacity of microwave radiation in this experiment. Our results revealed that microwave pretreatment of seeds enhanced UV-B stress resistance in the seedlings by decreasing the concentration of malondialdehyde (MDA) and increasing the concentration of ascorbic acid (AsA) and UV-B-absorbing compounds, increasing the activities of catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), and increasing the energy accumulation of photosynthesis. All these results suggest that microwave radiation enhances plant metabolism and results in increased UV-B stress resistance. This is the first investigation reporting the use of microwave pretreatment to protect the cells of Isatis indigotica from UV-B-induced lesions.

  3. Patient-centric Blood Pressure–targeted Cardiopulmonary Resuscitation Improves Survival from Cardiac Arrest

    PubMed Central

    Friess, Stuart H.; Naim, Maryam Y.; Lampe, Joshua W.; Bratinov, George; Weiland, Theodore R.; Garuccio, Mia; Nadkarni, Vinay M.; Becker, Lance B.; Berg, Robert A.

    2014-01-01

    Rationale: Although current resuscitation guidelines are rescuer focused, the opportunity exists to develop patient-centered resuscitation strategies that optimize the hemodynamic response of the individual in the hopes to improve survival. Objectives: To determine if titrating cardiopulmonary resuscitation (CPR) to blood pressure would improve 24-hour survival compared with traditional CPR in a porcine model of asphyxia-associated ventricular fibrillation (VF). Methods: After 7 minutes of asphyxia, followed by VF, 20 female 3-month-old swine randomly received either blood pressure–targeted care consisting of titration of compression depth to a systolic blood pressure of 100 mm Hg and vasopressors to a coronary perfusion pressure greater than 20 mm Hg (BP care); or optimal American Heart Association Guideline care consisting of depth of 51 mm with standard advanced cardiac life support epinephrine dosing (Guideline care). All animals received manual CPR for 10 minutes before first shock. Primary outcome was 24-hour survival. Measurements and Main Results: The 24-hour survival was higher in the BP care group (8 of 10) compared with Guideline care (0 of 10); P = 0.001. Coronary perfusion pressure was higher in the BP care group (point estimate +8.5 mm Hg; 95% confidence interval, 3.9–13.0 mm Hg; P < 0.01); however, depth was higher in Guideline care (point estimate +9.3 mm; 95% confidence interval, 6.0–12.5 mm; P < 0.01). Number of vasopressor doses before first shock was higher in the BP care group versus Guideline care (median, 3 [range, 0–3] vs. 2 [range, 2–2]; P = 0.003). Conclusions: Blood pressure–targeted CPR improves 24-hour survival compared with optimal American Heart Association care in a porcine model of asphyxia-associated VF cardiac arrest. PMID:25321490

  4. A re-assessment of minocycline as a neuroprotective agent in a rat spinal cord contusion model.

    PubMed

    Pinzon, Alberto; Marcillo, Alexander; Quintana, Ada; Stamler, Sarah; Bunge, Mary Bartlett; Bramlett, Helen M; Dietrich, W Dalton

    2008-12-03

    This study was initiated due to an NIH "Facilities of Research--Spinal Cord Injury" contract to support independent replication of published studies that could be considered for a clinical trial in time. Minocycline has been shown to have neuroprotective effects in models of central nervous system injury, including in a contusive spinal cord injury (SCI) model at the thoracic level. Beneficial effects of minocycline treatment included a significant improvement in locomotor behavior and reduced histopathological changes [Lee, S.M., Yune, T.Y., Kim, S.J., Park, D.O.W., Lee, Y.K., Kim, Y.C., Oh, Y.J., Markelonis, G.J., Oh, T.H., 2003. Minocycline reduces cell death and improves functional recovery after traumatic spinal cord injury in the rat. J Neurotrauma. 20, 1017-1027.] To verify these important observations, we repeated this study in our laboratory. The NYU (MASCIS) Impactor was used to produce a moderate cord lesion at the vertebral level T9-T10 (height 12.5 mm, weight 10 g), (n=45), followed by administration of minocycline, 90 mg/kg (group 1: minocycline IP, n=15; group 2: minocycline IV, n=15; group 3: vehicle IP, n=8; group 4: vehicle IV, n=7) immediately after surgery and followed by two more doses of 45 mg/kg/IP at 12 h and 24 h. Open field locomotion (BBB) and subscores were examined up to 6 weeks after SCI and cords were processed for quantitative histopathological analysis. Administration of minocycline after SCI did not lead to significant behavioral or histopathological improvement. Although positive effects with minocycline have been reported in several animal models of injury with different drug administration schemes, the use of minocycline following contusive SCI requires further investigation before clinical trials are implemented.

  5. Influence of post pattern and resin cement curing mode on the retention of glass fibre posts.

    PubMed

    Poskus, L T; Sgura, R; Paragó, F E M; Silva, E M; Guimarães, J G A

    2010-04-01

    To evaluate the influence of post design and roughness and cement system (dual- or self-cured) on the retention of glass fibre posts. Two tapered and smooth posts (Exacto Cônico No. 2 and White Post No. 1) and two parallel-sided and serrated posts (Fibrekor 1.25 mm and Reforpost No. 2) were adhesively luted with two different resin cements--a dual-cured (Rely-X ARC) and a self-cured (Cement Post)--in 40 single-rooted teeth. The teeth were divided into eight experimental groups (n = 5): PFD--Parallel-serrated-Fibrekor/dual-cured; PRD--Parallel-serrated-Reforpost/dual-cured; TED--Tapered-smooth-Exacto Cônico/dual-cured; TWD--Tapered-smooth-White Post/dual-cured; PFS--Parallel-serrated-Fibrekor/self-cured; PRS--Parallel-serrated-Reforpost/self-cured; TES--Tapered-smooth-Exacto Cônico/self-cured; TWS--Tapered-smooth-White Post/self-cured. The specimens were submitted to a pull-out test at a crosshead speed of 0.5 mm min(-1). Data were analysed using analysis of variance and Bonferroni's multiple comparison test (alpha = 0.05). Pull-out results (MPa) were: PFD = 8.13 (+/-1.71); PRD = 8.30 (+/-0.46); TED = 8.68 (+/-1.71); TWD = 9.35 (+/-1.99); PFS = 8.54 (+/-2.23); PRS = 7.09 (+/-1.96); TES = 8.27 (+/-3.92); TWS = 7.57 (+/-2.35). No statistical significant difference was detected for posts and cement factors and their interaction. The retention of glass fibre posts was not affected by post design or surface roughness nor by resin cement-curing mode. These results imply that the choice for serrated posts and self-cured cements is not related to an improvement in retention.

  6. Hyoid Bone Development: An Assessment Of Optimal CT Scanner Parameters and Three-Dimensional Volume Rendering Techniques.

    PubMed

    Cotter, Meghan M; Whyms, Brian J; Kelly, Michael P; Doherty, Benjamin M; Gentry, Lindell R; Bersu, Edward T; Vorperian, Houri K

    2015-08-01

    The hyoid bone anchors and supports the vocal tract. Its complex shape is best studied in three dimensions, but it is difficult to capture on computed tomography (CT) images and three-dimensional volume renderings. The goal of this study was to determine the optimal CT scanning and rendering parameters to accurately measure the growth and developmental anatomy of the hyoid and to determine whether it is feasible and necessary to use these parameters in the measurement of hyoids from in vivo CT scans. Direct linear and volumetric measurements of skeletonized hyoid bone specimens were compared with corresponding CT images to determine the most accurate scanning parameters and three-dimensional rendering techniques. A pilot study was undertaken using in vivo scans from a retrospective CT database to determine feasibility of quantifying hyoid growth. Scanning parameters and rendering technique affected accuracy of measurements. Most linear CT measurements were within 10% of direct measurements; however, volume was overestimated when CT scans were acquired with a slice thickness greater than 1.25 mm. Slice-by-slice thresholding of hyoid images decreased volume overestimation. The pilot study revealed that the linear measurements tested correlate with age. A fine-tuned rendering approach applied to small slice thickness CT scans produces the most accurate measurements of hyoid bones. However, linear measurements can be accurately assessed from in vivo CT scans at a larger slice thickness. Such findings imply that investigation into the growth and development of the hyoid bone, and the vocal tract as a whole, can now be performed using these techniques.