Science.gov

Sample records for 1-mm slice thickness

  1. Thick Slice and Thin Slice Teaching Evaluations

    ERIC Educational Resources Information Center

    Tom, Gail; Tong, Stephanie Tom; Hesse, Charles

    2010-01-01

    Student-based teaching evaluations are an integral component to institutions of higher education. Previous work on student-based teaching evaluations suggest that evaluations of instructors based upon "thin slice" 30-s video clips of them in the classroom correlate strongly with their end of the term "thick slice" student evaluations. This study's…

  2. Holographic characteristics of a 1-mm-thick photopolymer to be used in holographic memories

    NASA Astrophysics Data System (ADS)

    Ortun~O, Manuel; Gallego, Sergi; García, Celia; Neipp, Cristian; Pascual, Inmaculada

    2003-12-01

    Poly(vinyl alcohol-acrylamide) photopolymers are materials of interest in the field of digital information storage (holographic memories). We analyzed the behavior of a 1-mm-thick photopolymer. Using a standard holographic setup, we recorded unslanted diffraction gratings. The material has high angular selectivity (0.4°), good sensitivity (88 mJ/cm2), and small losses caused by absorption and scattering of light. It also has a high maximum diffraction efficiency (70%). A significant induction period was seen in the material. The authors hypothesize that, during most of this induction period, polymerization does in fact take place but is not reflected in the appearance of the diffracted light until a certain threshold value of exposure is reached.

  3. Effect of slice thickness on brain magnetic resonance image texture analysis

    PubMed Central

    2010-01-01

    Background The accuracy of texture analysis in clinical evaluation of magnetic resonance images depends considerably on imaging arrangements and various image quality parameters. In this paper, we study the effect of slice thickness on brain tissue texture analysis using a statistical approach and classification of T1-weighted images of clinically confirmed multiple sclerosis patients. Methods We averaged the intensities of three consecutive 1-mm slices to simulate 3-mm slices. Two hundred sixty-four texture parameters were calculated for both the original and the averaged slices. Wilcoxon's signed ranks test was used to find differences between the regions of interest representing white matter and multiple sclerosis plaques. Linear and nonlinear discriminant analyses were applied with several separate training and test sets to determine the actual classification accuracy. Results Only moderate differences in distributions of the texture parameter value for 1-mm and simulated 3-mm-thick slices were found. Our study also showed that white matter areas are well separable from multiple sclerosis plaques even if the slice thickness differs between training and test sets. Conclusions Three-millimeter-thick magnetic resonance image slices acquired with a 1.5 T clinical magnetic resonance scanner seem to be sufficient for texture analysis of multiple sclerosis plaques and white matter tissue. PMID:20955567

  4. Brain tissue slice thickness monitored by ion-profile measurement.

    PubMed

    Lipinski, H G

    1992-04-01

    The thickness of a brain tissue slice preparation governs the amount of time required for substances to diffuse from the bathing solution to preparation. Slice thickness may increase during the experiment, e.g., in cases of hypoxia where osmotic pressure within the tissue changes, enabling water to enter the preparation. With increasing slice thickness diffusion paths from the bath to central layers of the preparation increase possibly resulting in an insufficient O2 supply to central layers. Therefore, the actual slice thickness should be monitored during the experiment especially in cases where osmolarity is changed or during hypoxia. This paper describes a simple method to monitor the actual slice thickness using ion profiles measured by ion selective micro-electrodes driven at a constant rate of approximately 10 microns/s (sample rate ca. 10/s). The method is based on steep changes in the concentration gradients at the upper and lower surfaces of the preparation induced by simple diffusion in the presence of concentration gradients between the non-tortuous bath and the tortuous tissue. The thickness of the preparation is derived from the location of the steep gradient changes as reflected by the registered profile. PMID:1405733

  5. [Investigation of Region of Interest (ROI) for measurement of slice thickness in Computed Tomography (CT)].

    PubMed

    Nakamura, Shinobu; Kawata, Hidemichi; Nanbu, Ryosuke; Ohkura, Sunao; Hayashida, Kazuya; Hayabuchi, Naofumi

    2010-03-20

    We evaluated an appropriate region of interest (ROI) size for the measurement of full width at half maximum (FWHM) in the bead method (0.1 mm and 0.5 mm diameter; lead) and the microdisk method (0.05 mm thickness and 1.0 mm diameter; tungsten) using multislice computed tomography (CT). The FWHM of preset slice thicknesses 0.625 mm, 1.25 mm, 5.0 mm and 7.5 mm were measured by varying helical pitch, location of measurement [center and off-center of scan field of view (SFOV)] and ROI size, and they were compared with the tolerance stated in the Japanese Industrial Standards (JIS). It was conlcuded that the appropriate ROI size was influenced by preset slice thickness in this study. At the center of SFOV, measurements of FWHM were enabled within the tolerance of the JIS with small variations in all preset slice thicknesses if the ROI sizes were set between 0.4 times and equal to the size of the bead or microdisk indicating the maximum CT value in the series of CT images. At the off-center of SFOV, the tendency of increasing FWHM was confirmed, but it was shown that variations of the off-center in thicker slice thickness were larger regardless of helical pitch when the orbital synchronized helical scan technique was not used. PMID:20379062

  6. Optimization of a 1 mm thick PVA/acrylamide recording material to obtain holographic memories: method of preparation and holographic properties

    NASA Astrophysics Data System (ADS)

    Ortuño, M.; Gallego, S.; García, C.; Neipp, C.; Beléndez, A.; Pascual, I.

    2003-07-01

    Information holographic storage is a very promising technique due to its high theoretical capacity. One of the key factors in developing holographic memories is the need for a suitable recording material which must have certain specific characteristics. In particular, in order to achieve a high storage density it is necessary to work with great thicknesses. One of the essential requirements for holographic memories to be competitive is that the material must have a thickness of 500 μm or more, but it is not easy to find such thicknesses with the photopolymers currently available. In this study, we develop a method of preparing layers of a polyvinyl alcohol/acrylamide based photopolymer approximately 1 mm thick. Optimization of this material makes it possible to obtain good results for the main holographic parameters; diffraction efficiency 70% and energetic sensitivity 50 mJ/cm2.

  7. Filter and slice thickness selection in SPECT image reconstruction

    SciTech Connect

    Ivanovic, M.; Weber, D.A.; Wilson, G.A.; O'Mara, R.E.

    1985-05-01

    The choice of filter and slice thickness in SPECT image reconstruction as function of activity and linear and angular sampling were investigated in phantom and patient imaging studies. Reconstructed transverse and longitudinal spatial resolution of the system were measured using a line source in a water filled phantom. Phantom studies included measurements of the Data Spectrum phantom; clinical studies included tomographic procedures in 40 patients undergoing imaging of the temporomandibular joint. Slices of the phantom and patient images were evaluated for spatial of the phantom and patient images were evaluated for spatial resolution, noise, and image quality. Major findings include; spatial resolution and image quality improve with increasing linear sampling frequencies over the range of 4-8 mm/p in the phantom images, best spatial resolution and image quality in clinical images were observed at a linear sampling frequency of 6mm/p, Shepp and Logan filter gives the best spatial resolution for phantom studies at the lowest linear sampling frequency; smoothed Shepp and Logan filter provides best quality images without loss of resolution at higher frequencies and, spatial resolution and image quality improve with increased angular sampling frequency in the phantom at 40 c/p but appear to be independent of angular sampling frequency at 400 c/p.

  8. SU-E-T-319: The Effect of Slice Thickness On IMRT Planning

    SciTech Connect

    Srivastava, S; Das, I; Cheng, C

    2014-06-01

    Purpose: The accuracy of volume estimated of a treatment planning system is investigated in this study. In addition, the effect of slice thickness on IMRT planning is also studied. Methods: The accuracy in volume determination was investigated using a water phantom containing various objects with known volumes ranging from 1–100cm{sup 3}. The phantom was scanned with different slice thickness (1–10 mm). The CT data sets were sent to Eclipse TPS for contour delineation and volume calculation. The effect of slice thickness on IMRT planning was studied using a commercial phantom containing four different shaped objects. The phantom was scanned with different slice thickness (1–5 mm). IMRT plans were generated for the different CT datasets to calculate TCP, homogeneity (HI) and conformity indices (CI). Results: The variability of volumes with CT slice thickness was significant especially for small volume structures. The minimum and maximum error in the volume estimation is in the range of −2.3% to 92%. On the other hand, with increasing slice thickness, the PTV mean dose and TCP values decreases. Maximum variation of ∼5% was observed in mean dose and ∼2% in TCP with slice thickness change from 1–5 mm. The relative decrease in target volume receiving 95% of prescribed dose is ∼5% slice thickness change from 1–5 mm. HI increases up to 163% and CI decreases by 4% between 1–5 mm slice thickness change, producing highly inhomogeneous and least conformal plan. Conclusion: Accuracy of volume estimation is dependent on CT slice thickness and the contouring algorithm in a TPS. During TPS commissioning and for all clinical protocols, evaluation of volume should be included to provide the limit of accuracy in DVH calculation. A smaller slice thickness provides superior dosimetry with improved TCP values. Thus, the smallest possible slice thickness should be used for IMRT planning.

  9. High-contrast X-ray radiography using hybrid semiconductor pixel detectors with 1 mm thick Si sensor as a tool for monitoring liquids in natural building stones

    NASA Astrophysics Data System (ADS)

    Krejci, F.; Slavikova, M.; Zemlicka, J.; Jakubek, J.; Kotlik, P.

    2014-07-01

    For the preservation of buildings and other cultural heritage, the application of various conservation products such as consolidants or water repellents is often used. X-ray radiography utilizing semiconductor particle-counting detectors stands out as a promising tool in research of consolidants inside natural building stones. However, a clear visualization of consolidation products is often accomplished by doping with a contrast agent, which presents a limitation. This approach causes a higher attenuation for X-rays, but also alters the penetration ability of the original consolidation product. In this contribution, we focus on the application of Medipix type detectors newly equipped with a 1 mm thick Si sensor. This thicker sensor has enhanced detection efficiency leading to extraordinary sensitivity for monitoring consolidants and liquids in natural building stones even without any contrast agent. Consequently, methods for the direct monitoring of organosilicon consolidants and dynamic visualization of the water uptake in the Opuka stone using high-contrast X-ray radiography are demonstrated. The presented work demonstrates a significant improvement in the monitoring sensitivity of X-ray radiography in stone consolidation studies and also shows advantages of this detector configuration for X-ray radiography in general.

  10. The effect of slice thickness on quantitation of in vivo renal volume with cine computed tomography

    SciTech Connect

    Lerman, L.O.; Bentley, M.D.; Bell, M.R.; Rumberger, J.A.; Romero, J.C. )

    1990-02-26

    The development of fast computed tomography (CT) scanners allows the accurate quantitations of the volume (V) of the in-vivo kidney (K) and its component tissues, using 3 mm thick slices. Utilizing thicker slices may potentially enable the use of shorter scan times with less exposure to contrast media. To determine the relative accuracy of such scans, the right Ks of 14 anesthetized dogs were first scanned, using 3mm thick slices, after a venous bolus injection of iohexol (0.5 cc/kg). The images were then averaged to produce 6 and 10 mm thick slices, and the Vs of the Ks, and their cortical and medullary Vs, determined after boundary identification. Following the scans, the Ks were excised and their Vs determined post-mortem by fluid displacement. The whole K Vs obtained with the 6 and 10 mm thick slices correlated well with those obtained with the 3 mm thick slices. The difference between the in vivo and the post-mortem renal and medullary Vs was consistent with the blood, filtrate and urine contents of the in vivo kidney. In conclusion, the use of 6 and 10 mm thick slices resulted in an overestimation of the in vivo cortical V due to a partial volume effect, which was reflected in a consistent overestimation of KV.

  11. Optical Sectioning and High Resolution in Single-Slice Structured Illumination Microscopy by Thick Slice Blind-SIM Reconstruction

    PubMed Central

    Jost, Aurélie; Tolstik, Elen; Feldmann, Polina; Wicker, Kai; Sentenac, Anne; Heintzmann, Rainer

    2015-01-01

    The microscope image of a thick fluorescent sample taken at a given focal plane is plagued by out-of-focus fluorescence and diffraction limited resolution. In this work, we show that a single slice of Structured Illumination Microscopy (two or three beam SIM) data can be processed to provide an image exhibiting tight sectioning and high transverse resolution. Our reconstruction algorithm is adapted from the blind-SIM technique which requires very little knowledge of the illumination patterns. It is thus able to deal with illumination distortions induced by the sample or illumination optics. We named this new algorithm thick slice blind-SIM because it models a three-dimensional sample even though only a single two-dimensional plane of focus was measured. PMID:26147644

  12. Evaluation of the possibility to use thick slabs of reconstructed outer breast tomosynthesis slice images

    NASA Astrophysics Data System (ADS)

    Petersson, Hannie; Dustler, Magnus; Tingberg, Anders; Timberg, Pontus

    2016-03-01

    The large image volumes in breast tomosynthesis (BT) have led to large amounts of data and a heavy workload for breast radiologists. The number of slice images can be decreased by combining adjacent image planes (slabbing) but the decrease in depth resolution can considerably affect the detection of lesions. The aim of this work was to assess if thicker slabbing of the outer slice images (where lesions seldom are present) could be a viable alternative in order to reduce the number of slice images in BT image volumes. The suggested slabbing (an image volume with thick outer slabs and thin slices between) were evaluated in two steps. Firstly, a survey of the depth of 65 cancer lesions within the breast was performed to estimate how many lesions would be affected by outer slabs of different thicknesses. Secondly, a selection of 24 lesions was reconstructed with 2, 6 and 10 mm slab thickness to evaluate how the appearance of lesions located in the thicker slabs would be affected. The results show that few malignant breast lesions are located at a depth less than 10 mm from the surface (especially for breast thicknesses of 50 mm and above). Reconstruction of BT volumes with 6 mm slab thickness yields an image quality that is sufficient for lesion detection for a majority of the investigated cases. Together, this indicates that thicker slabbing of the outer slice images is a promising option in order to reduce the number of slice images in BT image volumes.

  13. Influence of image slice thickness on rectal dose-response relationships following radiotherapy of prostate cancer

    PubMed Central

    Olsson, C.; Thor, M.; Liu, M.; Moissenko, V.; Petersen, S.E.; Høyer, M; Apte, A.; Deasy, J.O.

    2016-01-01

    When pooling retrospective data from different cohorts, slice thicknesses of acquired computed tomography (CT) images used for treatment planning may vary between cohorts. It is, however, not known if varying slice thickness influences derived dose-response relationships. We investigated this for rectal bleeding using dose-volume histograms (DVHs) of the rectum and rectal wall for dose distributions superimposed on images with varying CT slice thicknesses. We used dose and endpoint data from two prostate cancer cohorts treated with 3D-CRT to either 74 Gy (N=159) or 78 Gy (N=159) @ 2 Gy per fraction. The rectum was defined as the whole organ with content, and the morbidity cut-off was Grade ≥2 late rectal bleeding. Rectal walls were defined as 3-mm inner margins added to the rectum. DVHs for simulated slice thicknesses from 3 to 13 mm were compared to DVHs for the originally acquired slice thicknesses at 3 and 5 mm. Volumes, mean, and maximum doses were assessed from the DVHs, and gEUD values were calculated. For each organ and each of the simulated slice thicknesses, we performed predictive modeling of late rectal bleeding using the Lyman-Kutcher-Burman (LKB) model. For the most coarse slice thickness, rectal volumes increased (≤18%), whereas maximum and mean doses decreased (≤0.8 Gy and ≤4.2 Gy, respectively). For all a values, the gEUD for the simulated DVHs were ≤1.9 Gy different than the gEUD for the original DVHs. The best-fitting LKB model parameter values with 95% CIs were consistent between all DVHs. In conclusion, we found that the investigated slice thickness variations had minimal impact on rectal dose-response estimations. From the perspective of predictive modeling, our results suggest that variations within 10 mm in slice thickness between cohorts are unlikely to be a limiting factor when pooling multi-institutional rectal dose data that include slice thickness variations within this range. PMID:24936956

  14. Influence of image slice thickness on rectal dose-response relationships following radiotherapy of prostate cancer

    NASA Astrophysics Data System (ADS)

    Olsson, C.; Thor, M.; Liu, M.; Moissenko, V.; Petersen, S. E.; Høyer, M.; Apte, A.; Deasy, J. O.

    2014-07-01

    When pooling retrospective data from different cohorts, slice thicknesses of acquired computed tomography (CT) images used for treatment planning may vary between cohorts. It is, however, not known if varying slice thickness influences derived dose-response relationships. We investigated this for rectal bleeding using dose-volume histograms (DVHs) of the rectum and rectal wall for dose distributions superimposed on images with varying CT slice thicknesses. We used dose and endpoint data from two prostate cancer cohorts treated with three-dimensional conformal radiotherapy to either 74 Gy (N = 159) or 78 Gy (N = 159) at 2 Gy per fraction. The rectum was defined as the whole organ with content, and the morbidity cut-off was Grade ≥2 late rectal bleeding. Rectal walls were defined as 3 mm inner margins added to the rectum. DVHs for simulated slice thicknesses from 3 to 13 mm were compared to DVHs for the originally acquired slice thicknesses at 3 and 5 mm. Volumes, mean, and maximum doses were assessed from the DVHs, and generalized equivalent uniform dose (gEUD) values were calculated. For each organ and each of the simulated slice thicknesses, we performed predictive modeling of late rectal bleeding using the Lyman-Kutcher-Burman (LKB) model. For the most coarse slice thickness, rectal volumes increased (≤18%), whereas maximum and mean doses decreased (≤0.8 and ≤4.2 Gy, respectively). For all a values, the gEUD for the simulated DVHs were ≤1.9 Gy different than the gEUD for the original DVHs. The best-fitting LKB model parameter values with 95% CIs were consistent between all DVHs. In conclusion, we found that the investigated slice thickness variations had minimal impact on rectal dose-response estimations. From the perspective of predictive modeling, our results suggest that variations within 10 mm in slice thickness between cohorts are unlikely to be a limiting factor when pooling multi-institutional rectal dose data that include slice thickness

  15. Culturing thick brain slices: An interstitial 3D microperfusion system for enhanced viability

    PubMed Central

    Rambani, Komal; Vukasinovic, Jelena; Glezer, Ari; Potter, Steve M.

    2009-01-01

    Brain slice preparations are well-established models for a wide spectrum of in vitro investigations in the neuroscience discipline. However, these investigations are limited to acute preparations or thin organotypic culture preparations due to the lack of a successful method that allows culturing of thick organotypic brain slices. Thick brain slice cultures suffer necrosis due to ischemia deep in the tissue resulting from a destroyed circulatory system and subsequent diffusion-limited supply of nutrients and oxygen. Although thin organotypic brain slice cultures can be successfully cultured using a well established roller tube method (a monolayer organotypic culture) (Gahwiler B H, 1981) or a membrane insert method (up to 1–4 cell layers, <150μm)(Stoppini L et al., 1991), these methods fail to support thick tissue preparations. A few perfusion methods (using submerged or interface/microfluidic chambers) have been reported to enhance the longevity (up to few hours) of acute slice preparations (up to 600μm thick) (Hass H L et al., 1979; Nicoll R A and Alger B E, 1981; Passeraub P A et al., 2003). Here, we report a unique interstitial microfluidic perfusion technique to culture thick (700μm) organotypic brain slices. The design of the custom-made micro-perfusion chamber facilitates laminar, interstitial perfusion of oxygenated nutrient medium throughout the tissue thickness with concomitant removal of depleted medium and catabolites. We examined the utility of this perfusion method to enhance the viability of the thick organotypic brain slice cultures after 2 days and 5 days in vitro (DIV). We investigated the range of amenable flow rates that enhance the viability of 700μm thick organotypic brain slices compared to the unperfused control cultures. Our perfusion method allows up to 84.6% viability (P<0.01) and up to 700μm thickness, even after 5 DIV. Our results also confirm that these cultures are functionally active and have their in vivo cytoarchitecture

  16. The effect of temperature and slice thickness on drying kinetics tomato in the infrared dryer

    NASA Astrophysics Data System (ADS)

    Sadin, Rasool; Chegini, Gholam-Reza; Sadin, Hassan

    2014-04-01

    In this study thin layer drying of tomato slices were investigated in the infrared dryer. Drying rate increased with increasing temperature and reduction thickness and thus reduced the drying time. The effective diffusivity increased with increasing temperature and with increasing thickness of the samples. The effective diffusivity values changed from 1.094 × 10-9 to 4.468 × 10-9 m2/s and for activation energy varied from 110 to 120 kJ/mol. The best model for drying process of tomato slices was Midilli model.

  17. Additional Merits of Two-dimensional Single Thick-slice Magnetic Resonance Myelography in Spinal Imaging

    PubMed Central

    Aggarwal, Abhishek; Azad, Rajiv; Ahmad, Armeen; Arora, Pankaj; Gupta, Puneet

    2012-01-01

    Objective: To validate the additional merits of two-dimensional (2D) single thick-slice Magnetic Resonance Myelography (MRM) in spinal imaging. Materials and Methods: 2D single thick-slice MRM was performed using T2 half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence in addition to routine Magnetic resonance (MR) sequences for spine in 220 patients. The images were evaluated for additional diagnostic information in spinal and extra-spinal regions. A three-point grading system was adopted depending upon the utility of MRM in contributing to the detection of spinal or extra-spinal findings. Grade 1 represented no contribution of MRM while grade 3 would indicate that it was essential to detection of findings. Results: Utility of MRM in spine was categorized as grade 3 in 10.9% cases (24/220), grade 2 in 21.8% (48/220) cases and grade 1 in 67.3% cases (148/220). Thus, the overall additional merit of MRM in spine was seen in 32.7% (72/220) of cases. Besides in 14.1% cases (31/220) extra-spinal pathologies were identified. Conclusion: 2D single thick-slice MRM could have additional merits in spinal imaging when used as an adjunct to routine MR sequences. PMID:23393640

  18. A Rapid Approach to High-Resolution Fluorescence Imaging in Semi-Thick Brain Slices

    PubMed Central

    Selever, Jennifer; Kong, Jian-Qiang; Arenkiel, Benjamin R.

    2011-01-01

    preparation, or cost-prohibitive instrumentation respectively. Here, we present a relatively rapid and simple method to visualize fluorescently labelled cells in fixed semi-thick mouse brain slices by optical clearing and imaging. In the attached protocol we describe the methods of: 1) fixing brain tissue in situ via intracardial perfusion, 2) dissection and removal of whole brain, 3) stationary brain embedding in agarose, 4) precision semi-thick slice preparation using new vibratome instrumentation, 5) clearing brain tissue through a glycerol gradient, and 6) mounting on glass slides for light microscopy and z-stack reconstruction (Figure 1). For preparing brain slices we implemented a relatively new piece of instrumentation called the 'Compresstome' VF-200 (http://www.precisionary.com/products_vf200.html). This instrument is a semi-automated microtome equipped with a motorized advance and blade vibration system with features similar in function to other vibratomes. Unlike other vibratomes, the tissue to be sliced is mounted in an agarose plug within a stainless steel cylinder. The tissue is extruded at desired thicknesses from the cylinder, and cut by the forward advancing vibrating blade. The agarose plug/cylinder system allows for reproducible tissue mounting, alignment, and precision cutting. In our hands, the 'Compresstome' yields high quality tissue slices for electrophysiology, immunohistochemistry, and direct fixed-tissue mounting and imaging. Combined with optical clearing, here we demonstrate the preparation of semi-thick fixed brain slices for high-resolution fluorescent imaging. PMID:21841756

  19. Effect of slice thickness and blanching time on different quality attributes of instant ginger candy.

    PubMed

    Nath, A; Deka, Bidyut C; Jha, A K; Paul, D; Misra, L K

    2013-02-01

    Fresh ginger (Zingiber officinale Rosc.) suffers from weight loss, shrinkage, sprouting and rotting during storage after 3-4 weeks. This spoilage may be overcome by processing fresh produce to some value added products. An attempt was made to optimize the protocol for production of instant ginger candy. The experimental parameters considered were slice thickness (5.0-25.0 mm) and blanching duration (10-30 min) followed by dipping in 40°B and 75°B sugar solutions containing 2.0% citric acid respectively, for 1 and 2 h at 95 °C and dried at 60 °C for 1 h. RSM design was considered for this experiment and final products were evaluated for their textural properties, TSS, acidity, TSS: acid ratio, taste score and overall acceptability. The optimum product qualities in terms of hardness (2.08 kg), TSS (73.4%), acidity (1.31%), TSS: acid ratio (56.3), taste score (7.98) and overall acceptability (8.07) were obtained for slice thickness of 10.9 mm and blanching time of 24.9 min. PMID:24425909

  20. Measurement of slice thickness and in-plane resolution on radiographic tomosynthesis system using modulation transfer function (MTF)

    NASA Astrophysics Data System (ADS)

    Li, Baojun; Saunders, Rowland; Uppaluri, Renuka

    2006-03-01

    A novel method to measure in-plane resolution (modulation transfer function, or MTF) and slice thickness (slice sensitivity profile, or SSP) of a digital radiographic tomosynthesis system is presented. With this method, one can measure these two important system IQ characteristics simultaneously without suffering from incontinuous sampling, aliasing, and partial volume effect as do the existing methods. The method is based on imaging a shallow-angled slice ramp phantom. The MTF is measured as the HWHM of the Fourier transformation of the first derivative of edge profiles. The HWHM corresponding to the sharpest of edge profile represents the in-plane resolution of the system, and the slice thickness of the system is determined from the HWHM vs. z-distance curve. The in-plane resolution result has been confirmed by the measurement from an animal skull specimen. The experiment results have shown that, for a typical 40-degree sweep, 61 projections, and using a Specialized Filtered Backprojection (SFBP) algorithm, the in-plane resolution of the measured system is close to 1 lp/mm (as measured by the HWHM of MTF), and effective slice thickness is 1.7 mm and 4.0 mm at HWHM and HW3TM, respectively. It is also observed that, while the in-plane resolution remains constant between planes at 7 cm and 30 cm above the detector plane, SSP has increased (i.e., slice thickness increased) 20% on average with the increase of the plane height. We demonstrate one of the applications of the method to optimize the sweep angle of a tomosynthesis system. The results show that, in a typical angular range from 20 to 60 degrees, the increase in sweep angle can intrinsically reduce slice thickness but less significantly impact in-plane resolution.

  1. The relationship between decorrelation time and sample thickness in acute rat brain tissue slices (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Brake, Joshua; Jang, Mooseok; Yang, Changhuei

    2016-03-01

    The optical opacity of biological tissue has long been a challenge in biomedical optics due to the strong scattering nature of tissue in the optical regime. While most conventional optical techniques attempt to gate out multiply scattered light and use only unscattered light, new approaches in the field of wavefront shaping exploit the time reversible symmetry of optical scattering in order to focus light inside or through scattering media. While these approaches have been demonstrated effectively on static samples, it has proven difficult to apply them to dynamic biological samples since even small changes in the relative positions of the scatterers within will cause the time symmetry that wavefront shaping relies upon to decorrelate. In this paper we investigate the decorrelation curves of acute rat brain slices for thicknesses in the range 1-3 mm (1/e decorrelation time on the order of seconds) using multi-speckle diffusing wave spectroscopy (MSDWS) and compare the results with theoretical predictions. The results of this study demonstrate that the 1/L^2 relationship between decorrelation time and thickness predicted by diffusing wave spectroscopy provides a good rule of thumb for estimating how the decorrelation of a sample will change with increasing thickness. Understanding this relationship will provide insight to guide the future development of biophotonic wavefront shaping tools by giving an estimate of how fast wavefront shaping systems need to operate to overcome the dynamic nature of biological samples.

  2. Use of single-slice thick slab phase-contrast angiography for the diagnosis of dural venous sinus thrombosis.

    PubMed

    Adams, W M; Laitt, R D; Beards, S C; Kassner, A; Jackson, A

    1999-01-01

    The aim of this study was to examine the reliability of single-slice phase-contrast angiography (SSPCA) as a rapid technique for the investigation of suspected dural venous sinus occlusion. Images were obtained on 25 normal volunteers to document the accuracy of SSPCA in the demonstration of slow flow states. Normal volunteers were imaged using sagittal and coronal SSPCA (slice thickness 13 cm, matrix 256 x 256, TR 14 ms, TE 7 ms, flip angle 20 degrees, peak velocity encoding rate 30 cm/s). Sinus patency and flow rate were confirmed by measurement of flow in the superior sagittal and transverse sinuses using quantified single-slice phase difference images. Imaging was performed in 50 patients undergoing routine brain scans in order to determine the optimal slice orientation for clinical use. Twenty-one patients with suspected dural venous sinus thrombosis were also investigated with SSPCA and the diagnosis confirmed by one or more alternative imaging techniques. Imaging time was 29 s per acquisition and image quality was good in all cases. Variations in dural sinus patency and flow in normal volunteers were accurately predicted by SSPCA (kappa = 0.92). Use of a single angulated slice (130 mm thick, para-sagittal image angled 30 degrees towards coronal and 30 degrees towards transverse) provided sufficient separation of right- and left-sided venous structures to allow use of a single projection. The presence and extent of sinus occlusions in 14 patients and the absence of thrombosis in 7 were accurately identified by SSPCA. Sensitivity and specificity in this limited study were both 100%. The SSPCA technique takes less than 30 s and provides a reliable and rapid technique for the diagnosis of dural venous sinus thrombosis. PMID:10525876

  3. Model based iterative reconstruction IMR gives possibility to evaluate thinner slice thicknesses than conventional iterative reconstruction iDose4: a phantom study

    NASA Astrophysics Data System (ADS)

    Aurumskjöld, Marie-Louise; Ydström, Kristina; Tingberg, Anders; Söderberg, Marcus

    2015-03-01

    Computed tomography (CT) is one of the most important modalities in a radiological department, which produces images with high diagnostic confidence, but in some cases contributes to a high radiation dose to the patient. The radiation dose can be reduced by the use of advanced image reconstruction algorithms. This study was done on a Philips Brilliance iCT with iterative reconstruction iDose4 and model-based iterative reconstruction IMR. The purpose was to investigate the effect on the image quality with thin slice images reconstructed with IMR, compared to standard slice thickness reconstructed with iDose4. Objective measurements of noise and contrast-to-noise ratio were performed using an image quality phantom, an anthropomorphic phantom and clinical cases. Subjective evaluations of low-contrast resolution were performed by observers using an image quality phantom. IMR gives strong noise reduction and enhanced low-contrast and thereby enable selection of thinner slice thickness. Objective evaluation of image noise shows that thin slices reconstructed with IMR provides lower noise than thicker slice images reconstructed with iDose4. With IMR the slice thickness is of less importance for the noise. With thinner slices the partial volume artefacts becomes less pronounced. In conclusion, we have shown that IMR enables reduction of the slice thickness and at the same time maintain or even reduce the noise level compared to iDose4 reconstruction with standard slice thickness. This will subsequently result in an improvement of image quality for images reconstructed with IMR.

  4. Analyzing the relationship between decorrelation time and tissue thickness in acute rat brain slices using multispeckle diffusing wave spectroscopy.

    PubMed

    Brake, Joshua; Jang, Mooseok; Yang, Changhuei

    2016-02-01

    Novel techniques in the field of wavefront shaping have enabled light to be focused deep inside or through scattering media such as biological tissue. However, most of these demonstrations have been limited to thin, static samples since these techniques are very sensitive to changes in the arrangement of the scatterers within. As the samples of interest get thicker, the influence of the dynamic nature of the sample becomes even more pronounced and the window of time in which the wavefront solutions remain valid shrinks further. In this paper, we examine the time scales upon which this decorrelation happens in acute rat brain slices via multispeckle diffusing wave spectroscopy and investigate the relationship between this decorrelation time and the thickness of the sample using diffusing wave spectroscopy theory and Monte Carlo photon transport simulation. PMID:26831778

  5. Analyzing the relationship between decorrelation time and tissue thickness in acute rat brain slices using multispeckle diffusing wave spectroscopy

    PubMed Central

    Brake, Joshua; Jang, Mooseok; Yang, Changhuei

    2016-01-01

    Novel techniques in the field of wavefront shaping have enabled light to be focused deep inside or through scattering media such as biological tissue. However, most of these demonstrations have been limited to thin, static samples since these techniques are very sensitive to changes in the arrangement of the scatterers within. As the samples of interest get thicker, the influence of the dynamic nature of the sample becomes even more pronounced and the window of time in which the wavefront solutions remain valid shrinks further. In this paper, we examine the time scales upon which this decorrelation happens in acute rat brain slices via multispeckle diffusing wave spectroscopy and investigate the relationship between this decorrelation time and the thickness of the sample using diffusing wave spectroscopy theory and Monte Carlo photon transport simulation. PMID:26831778

  6. 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

  7. Influence of Thin Slice Reconstruction on CT Brain Perfusion Analysis

    PubMed Central

    Bennink, Edwin; Oosterbroek, Jaap; Horsch, Alexander D.; Dankbaar, Jan Willem; Velthuis, Birgitta K.; Viergever, Max A.; de Jong, Hugo W. A. M.

    2015-01-01

    Objectives Although CT scanners generally allow dynamic acquisition of thin slices (1 mm), thick slice (≥5 mm) reconstruction is commonly used for stroke imaging to reduce data, processing time, and noise level. Thin slice CT perfusion (CTP) reconstruction may suffer less from partial volume effects, and thus yield more accurate quantitative results with increased resolution. Before thin slice protocols are to be introduced clinically, it needs to be ensured that this does not affect overall CTP constancy. We studied the influence of thin slice reconstruction on average perfusion values by comparing it with standard thick slice reconstruction. Materials and Methods From 50 patient studies, absolute and relative hemisphere averaged estimates of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and permeability-surface area product (PS) were analyzed using 0.8, 2.4, 4.8, and 9.6 mm slice reconstructions. Specifically, the influence of Gaussian and bilateral filtering, the arterial input function (AIF), and motion correction on the perfusion values was investigated. Results Bilateral filtering gave noise levels comparable to isotropic Gaussian filtering, with less partial volume effects. Absolute CBF, CBV and PS were 22%, 14% and 46% lower with 0.8 mm than with 4.8 mm slices. If the AIF and motion correction were based on thin slices prior to reconstruction of thicker slices, these differences reduced to 3%, 4% and 3%. The effect of slice thickness on relative values was very small. Conclusions This study shows that thin slice reconstruction for CTP with unaltered acquisition protocol gives relative perfusion values without clinically relevant bias. It does however affect absolute perfusion values, of which CBF and CBV are most sensitive. Partial volume effects in large arteries and veins lead to overestimation of these values. The effects of reconstruction slice thickness should be taken into account when absolute perfusion values are

  8. Automatic identification of intracranial hemorrhage in non-contrast CT with large slice thickness for trauma cases

    NASA Astrophysics Data System (ADS)

    Maduskar, Pragnya; Acharyya, Mausumi

    2009-02-01

    In this paper we propose a technique for automatic detection of intracranial hemorrhage (ICH) and acute intracranial hemorrhage (AIH) in brain Computed Tomography (CT) for trauma cases where no contrast can be applied and the CT has large slice thickness. ICH or AIH comprise of internal bleeding (intra-axial) or external (extra-axial) to the brain substance. Large bleeds like in intra-axial region are easy to diagnose whereas it can be challenging if small bleed occurs in extra-axial region particularly in the absence of contrast. Bleed region needs to be distinguished from bleed-look-alike brain regions which are abnormally bright falx and fresh flowing blood. We propose an algorithm for detection of brain bleed in various anatomical locations. A preprocessing step is performed to segment intracranial contents and enhancement of region of interests(ROIs). A number of bleed and bleed-look-alike candidates are identified from a set of 11 available cases. For each candidate texture based features are extracted from non-separable quincunx wavelet transform along with some other descriptive features. The candidates are randomly divided into a training and test set consisting of both bleed and bleed-look- alike. A supervised classifier is designed based on the training sample features. A performance accuracy of 96% is attained for the independent test candidates.

  9. Communication: Time- and space-sliced velocity map electron imaging

    SciTech Connect

    Lee, Suk Kyoung; Lin, Yun Fei; Lingenfelter, Steven; Fan, Lin; Winney, Alexander H.; Li, Wen

    2014-12-14

    We develop a new method to achieve slice electron imaging using a conventional velocity map imaging apparatus with two additional components: a fast frame complementary metal-oxide semiconductor camera and a high-speed digitizer. The setup was previously shown to be capable of 3D detection and coincidence measurements of ions. Here, we show that when this method is applied to electron imaging, a time slice of 32 ps and a spatial slice of less than 1 mm thick can be achieved. Each slice directly extracts 3D velocity distributions of electrons and provides electron velocity distributions that are impossible or difficult to obtain with a standard 2D imaging electron detector.

  10. Efficacy of UV-C irradiation for inactivation of food-borne pathogens on sliced cheese packaged with different types and thicknesses of plastic films.

    PubMed

    Ha, Jae-Won; Back, Kyeong-Hwan; Kim, Yoon-Hee; Kang, Dong-Hyun

    2016-08-01

    In this study, the efficacy of using UV-C light to inactivate sliced cheese inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes and, packaged with 0.07 mm films of polyethylene terephthalate (PET), polyvinylchloride (PVC), polypropylene (PP), and polyethylene (PE) was investigated. The results show that compared with PET and PVC, PP and PE films showed significantly reduced levels of the three pathogens compared to inoculated but non-treated controls. Therefore, PP and PE films of different thicknesses (0.07 mm, 0.10 mm, and 0.13 mm) were then evaluated for pathogen reduction of inoculated sliced cheese samples. Compared with 0.10 and 0.13 mm, 0.07 mm thick PP and PE films did not show statistically significant reductions compared to non-packaged treated samples. Moreover, there were no statistically significant differences between the efficacy of PP and PE films. These results suggest that adjusted PP or PE film packaging in conjunction with UV-C radiation can be applied to control foodborne pathogens in the dairy industry. PMID:27052716

  11. Automated airway evaluation system for multi-slice computed tomography using airway lumen diameter, airway wall thickness and broncho-arterial ratio

    NASA Astrophysics Data System (ADS)

    Odry, Benjamin L.; Kiraly, Atilla P.; Novak, Carol L.; Naidich, David P.; Lerallut, Jean-Francois

    2006-03-01

    Pulmonary diseases such as bronchiectasis, asthma, and emphysema are characterized by abnormalities in airway dimensions. Multi-slice computed tomography (MSCT) has become one of the primary means to depict these abnormalities, as the availability of high-resolution near-isotropic data makes it possible to evaluate airways at oblique angles to the scanner plane. However, currently, clinical evaluation of airways is typically limited to subjective visual inspection only: systematic evaluation of the airways to take advantage of high-resolution data has not proved practical without automation. We present an automated method to quantitatively evaluate airway lumen diameter, wall thickness and broncho-arterial ratios. In addition, our method provides 3D visualization of these values, graphically illustrating the location and extent of disease. Our algorithm begins by automatic airway segmentation to extract paths to the distal airways, and to create a map of airway diameters. Normally, airway diameters decrease as paths progress distally; failure to taper indicates abnormal dilatation. Our approach monitors airway lumen diameters along each airway path in order to detect abnormal profiles, allowing even subtle degrees of pathologic dilatation to be identified. Our method also systematically computes the broncho-arterial ratio at every terminal branch of the tree model, as a ratio above 1 indicates potentially abnormal bronchial dilatation. Finally, the airway wall thickness is computed at corresponding locations. These measurements are used to highlight abnormal branches for closer inspection, and can be summed to compute a quantitative global score for the entire airway tree, allowing reproducible longitudinal assessment of disease severity. Preliminary tests on patients diagnosed with bronchiectasis demonstrated rapid identification of lack of tapering, which also was confirmed by corresponding demonstration of elevated broncho-arterial ratios.

  12. Absolute brightness temperature measurements at 2.1-mm wavelength

    NASA Technical Reports Server (NTRS)

    Ulich, B. L.

    1974-01-01

    Absolute measurements of the brightness temperatures of the Sun, new Moon, Venus, Mars, Jupiter, Saturn, and Uranus, and of the flux density of DR21 at 2.1-mm wavelength are reported. Relative measurements at 3.5-mm wavelength are also preented which resolve the absolute calibration discrepancy between The University of Texas 16-ft radio telescope and the Aerospace Corporation 15-ft antenna. The use of the bright planets and DR21 as absolute calibration sources at millimeter wavelengths is discussed in the light of recent observations.

  13. Synchronized slice viewing of similar image series

    NASA Astrophysics Data System (ADS)

    Ali, Sharib; Foncubierta, Antonio; Depeursinge, Adrien; Meriaudeau, Fabrice; Ratib, Osman; Müller, Henning

    2012-02-01

    Comparing several series of images is not always easy as the corresponding slices often need to be selected manually. In times where series contain an ever-increasing number of slices this can mean manual work when moving several series to the corresponding slice. Particularly two situations were identified in this context: (1) patients with a large number of image series over time (such as patients with cancers that are monitored) frequently need to compare the series, for example to compare tumor growth over time. Manually adapting two series is possible but with four or more series this can mean loosing time. Having automatically the closest slice by comparing visual similarity also in older series with differing slice thickness and inter slice distance can save time and synchronize the viewing instantly. (2) analyzing visually similar image series of several patients can profit from being viewed in a synchronized way to compare the cases, so when sliding through the slices in one volume, the corresponding slices in the other volumes are shown. This application could be employed after content-based 3D image retrieval has found similar series, for example. Synchronized viewing can help finding or confirming the most relevant cases quickly. To allow for synchronized viewing of several image volumes, the test image series are first registered applying affine transformation for the global registration of images followed by diffeomorphic image registration. Then corresponding slices in the two volumes are estimated based on a visual similarity. Once the registration is finished, the user can subsequently move inside the slices of one volume (reference volume) and can view the corresponding slices in the other volumes. These corresponding slices are obtained after a correspondence match in the registration procedure. These volumes are synchronized in that the slice closest to the original reference volume is shown even when the slice thicknesses or inter slice

  14. Dark filaments observed at 8.3mm and 3.1mm wavelength

    NASA Technical Reports Server (NTRS)

    Hiel, E.; Ishiguro, M.; Kosugi, T.; Shibasaki, K.

    1986-01-01

    Mapping of the sun was made at 3.1mm (98 GHz) and 8.3mm (36 GHz) wavelengths with a 45m dish radio telescope at the Nobeyama Cosmic Radio Observatory. The depressions associated with large H alpha filaments are derived to be -0.2 at 8.3mm and -0.05 at 3.1mm, which are darker than the values inferred by Raoult et al. (1979)

  15. Development of mini-tablets with 1mm and 2mm diameter.

    PubMed

    Tissen, Corinna; Woertz, Katharina; Breitkreutz, Joerg; Kleinebudde, Peter

    2011-09-15

    The feasibility of formulating mini-tablets with 1mm diameter on a rotary-die press in comparison to mini-tablets of 2mm was investigated. To gain insight into the production of 1mm mini-tablets, three model drugs of different compression characteristics were chosen, namely quinine hydrochloride, ibuprofen and spray-dried gentian extract. A high drug load in combination with robust and reproducible mechanical properties was requested. Depending on the individual drug substance, mini-tablets were produced by direct compression or after roll-compaction/dry granulation. The tensile strength, mass, and their variation coefficients were determined to assess the mechanical properties of the tablets. The content uniformity and the dissolution behavior of selected batches were analyzed. For the first time 1mm mini-tablets could be successfully produced by direct compression (90% quinine hydrochloride; 90% dried gentian extract) and after roll compaction (70% ibuprofen). Depending on the applied compression pressure, 1mm mini-tablets with quinine hydrochloride exhibited robust mechanical properties (e.g. median tensile strength of 2.02N/mm(2)) with equal or lower variance of distribution compared to the 2mm compacts. With respect to content uniformity of dosage forms, 1mm mini-tablets containing 80% quinine hydrochloride met the requirements of the European Pharmacopeia (AV=6.8). PMID:21726616

  16. Additional atmospheric opacity measurements at lambda = 1.1 mm from Mauna Kea Observatory, Hawaii

    NASA Technical Reports Server (NTRS)

    Parrish, A.; De Zafra, R. L.; Barrett, J. W.; Solomon, P.; Connor, B.

    1987-01-01

    Atmospheric opacity values in the zenith direction are given for a wavelength of 1.1 mm (278 GHz) at the summit of Mauna Kea in the Hawaiian Islands. A total of 75 days is covered during the period 1983-1986. Observations were made on a quasi-continuous basis, with opacity measured every 20 minutes around the clock for significant periods of time. A conversion from opacity at lambda = 1.1 mm to the equivalent precipitable water vapor column is given from the measurements of Zammit and Ade (1981), from which opacities at other wavelengths may be derived.

  17. A Review of Variable Slicing in Fused Deposition Modeling

    NASA Astrophysics Data System (ADS)

    Nadiyapara, Hitesh Hirjibhai; Pande, Sarang

    2016-06-01

    The paper presents a literature survey in the field of fused deposition of plastic wires especially in the field of slicing and deposition using extrusion of thermoplastic wires. Various researchers working in the field of computation of deposition path have used their algorithms for variable slicing. In the study, a flowchart has also been proposed for the slicing and deposition process. The algorithm already been developed by previous researcher will be used to be implemented on the fused deposition modelling machine. To demonstrate the capabilities of the fused deposition modeling machine a case study has been taken. It uses a manipulated G-code to be fed to the fused deposition modeling machine. Two types of slicing strategies, namely uniform slicing and variable slicing have been evaluated. In the uniform slicing, the slice thickness has been used for deposition is varying from 0.1 to 0.4 mm. In the variable slicing, thickness has been varied from 0.1 in the polar region to 0.4 in the equatorial region Time required and the number of slices required to deposit a hemisphere of 20 mm diameter have been compared with that using the variable slicing.

  18. Parametric Trace Slicing

    NASA Technical Reports Server (NTRS)

    Rosu, Grigore (Inventor); Chen, Feng (Inventor); Chen, Guo-fang; Wu, Yamei; Meredith, Patrick O. (Inventor)

    2014-01-01

    A program trace is obtained and events of the program trace are traversed. For each event identified in traversing the program trace, a trace slice of which the identified event is a part is identified based on the parameter instance of the identified event. For each trace slice of which the identified event is a part, the identified event is added to an end of a record of the trace slice. These parametric trace slices can be used in a variety of different manners, such as for monitoring, mining, and predicting.

  19. Effect of simultaneous infrared dry-blanching and dehydration on quality characteristics of carrot slices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated the effects of various processing parameters on carrot slices exposed to infrared (IR) radiation heating for achieving simultaneous infrared dry-blanching and dehydration (SIRDBD). The investigated parameters were product surface temperature, slice thickness and processing ti...

  20. Automated Factor Slice Sampling.

    PubMed

    Tibbits, Matthew M; Groendyke, Chris; Haran, Murali; Liechty, John C

    2014-01-01

    Markov chain Monte Carlo (MCMC) algorithms offer a very general approach for sampling from arbitrary distributions. However, designing and tuning MCMC algorithms for each new distribution, can be challenging and time consuming. It is particularly difficult to create an efficient sampler when there is strong dependence among the variables in a multivariate distribution. We describe a two-pronged approach for constructing efficient, automated MCMC algorithms: (1) we propose the "factor slice sampler", a generalization of the univariate slice sampler where we treat the selection of a coordinate basis (factors) as an additional tuning parameter, and (2) we develop an approach for automatically selecting tuning parameters in order to construct an efficient factor slice sampler. In addition to automating the factor slice sampler, our tuning approach also applies to the standard univariate slice samplers. We demonstrate the efficiency and general applicability of our automated MCMC algorithm with a number of illustrative examples. PMID:24955002

  1. Automated Factor Slice Sampling

    PubMed Central

    Tibbits, Matthew M.; Groendyke, Chris; Haran, Murali; Liechty, John C.

    2013-01-01

    Markov chain Monte Carlo (MCMC) algorithms offer a very general approach for sampling from arbitrary distributions. However, designing and tuning MCMC algorithms for each new distribution, can be challenging and time consuming. It is particularly difficult to create an efficient sampler when there is strong dependence among the variables in a multivariate distribution. We describe a two-pronged approach for constructing efficient, automated MCMC algorithms: (1) we propose the “factor slice sampler”, a generalization of the univariate slice sampler where we treat the selection of a coordinate basis (factors) as an additional tuning parameter, and (2) we develop an approach for automatically selecting tuning parameters in order to construct an efficient factor slice sampler. In addition to automating the factor slice sampler, our tuning approach also applies to the standard univariate slice samplers. We demonstrate the efficiency and general applicability of our automated MCMC algorithm with a number of illustrative examples. PMID:24955002

  2. Microhardness of composite resin cured through different primary tooth thicknesses with different light intensities and curing times: In vitro study

    PubMed Central

    Mazhari, Fatemeh; Ajami, Behjatolmolok; Moazzami, Saied Mostafa; Baghaee, Bahareh; Hafez, Bahareh

    2016-01-01

    Objective: The aim of this study was to evaluate the effect of increased exposure time and light intensity on microhardness of cured composite through different thicknesses of tooth structure in primary teeth. Materials and Methods: One hundred and seventy cylindrical resin composite specimens were prepared. All specimens were divided into 17 experimental and control groups. “Light-emitting diode” light curing unit (LCU) applied directly or through 1, 2, and 3 mm thicknesses tooth slices for experimental groups. The irradiation protocols were 25 and 50 s at 650 mW/cm2 and 15 and 30 s at 1100 mW/cm2. The “quartz-tungsten-halogen” LCU (400 mW/cm2) for 40 s was used in control group. Microhardness was measured by the Vickers hardness test. Results: Indirectly cured specimens and those cured through a 1 mm thick tooth structure, an increase in intensity caused hardness drop. In the specimens cured through 2 and 3 mm thick tooth structures, increased intensity and/or exposure time did not show any appropriate changes on microhardness. Conclusion: Irradiation through a 1.0 mm thick tooth slice resulted in reduced microhardness although it was still within the clinically acceptable level. The hardness values of the specimens cured through 2 or 3 mm thick tooth slices fell below the clinically acceptable level even after doubling the exposure time and/or light intensity. PMID:27095897

  3. AzTEC 1.1 mm OBSERVATIONS OF THE MBM12 MOLECULAR CLOUD

    SciTech Connect

    Kim, M. J.; Kim, S.; Youn, S.; Kang, Y.-W.; Yun, M. S.; Wilson, G. W.; Aretxaga, I.; Hughes, D. H.; Humphrey, A.; Williams, J. P.; Austermann, J. E.; Perera, T. A.; Mauskopf, P. D.; Magnani, L.

    2012-02-10

    We present 1.1 mm observations of the dust continuum emission from the MBM12 high-latitude molecular cloud observed with the Astronomical Thermal Emission Camera (AzTEC) mounted on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. We surveyed 6.34 deg{sup 2} centered on MBM12, making this the largest area that has ever been surveyed in this region with submillimeter and millimeter telescopes. Eight secure individual sources were detected with a signal-to-noise ratio of over 4.4. These eight AzTEC sources can be considered to be real astronomical objects compared to the other candidates based on calculations of the false detection rate. The distribution of the detected 1.1 mm sources or compact 1.1 mm peaks is spatially anti-correlated with that of the 100 {mu}m emission and the {sup 12}CO emission. We detected the 1.1 mm dust continuum emitting sources associated with two classical T Tauri stars, LkH{alpha}262 and LkH{alpha}264. Observations of spectral energy distributions (SEDs) indicate that LkH{alpha}262 is likely to be Class II (pre-main-sequence star), but there are also indications that it could be a late Class I (protostar). A flared disk and a bipolar cavity in the models of Class I sources lead to more complicated SEDs. From the present AzTEC observations of the MBM12 region, it appears that other sources detected with AzTEC are likely to be extragalactic and located behind MBM12. Some of these have radio counterparts and their star formation rates are derived from a fit of the SEDs to the photometric evolution of galaxies in which the effects of a dusty interstellar medium have been included.

  4. SXDF-ALMA 2-arcmin2 deep survey: 1.1-mm number counts

    NASA Astrophysics Data System (ADS)

    Hatsukade, Bunyo; Kohno, Kotaro; Umehata, Hideki; Aretxaga, Itziar; Caputi, Karina I.; Dunlop, James S.; Ikarashi, Soh; Iono, Daisuke; Ivison, Rob J.; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Motohara, Kentaro; Nakanishi, Kouichiro; Ohta, Kouji; Tadaki, Ken-ich; Tamura, Yoichi; Wang, Wei-Hao; Wilson, Grant W.; Yamaguchi, Yuki; Yun, Min S.

    2016-06-01

    We report 1.1-mm number counts revealed with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey Field (SXDF). The advent of ALMA enables us to reveal millimeter-wavelength number counts down to the faint end without source confusion. However, previous studies are based on the ensemble of serendipitously detected sources in fields originally targeting different sources and could be biased due to the clustering of sources around the targets. We derive number counts in the flux range of 0.2-2 mJy by using 23 (≥4σ) sources detected in a continuous 2.0-arcmin2 area of the SXDF. The number counts are consistent with previous results within errors, suggesting that the counts derived from serendipitously detected sources are not significantly biased, although there could be field-to-field variation due to the small survey area. By using the best-fitting function of the number counts, we find that ˜40% of the extragalactic background light at 1.1 mm is resolved at S1.1mm > 0.2 mJy.

  5. [A simple vibratome for brain slice].

    PubMed

    Xia, J H; Xing, B R; Gu, Q; Hua, S Y

    1989-12-01

    A simple vibratome was fabricated using double-function electric shaver and microscopic platform. Spontaneous discharge of neurons in hippocampal and hypothalamic brain slices (in 300-400 microns thick) prepared by the vibratome could kept above 12 hours in artificial cerebro-spinal fluid. PMID:2697084

  6. Profile analysis of hepatic porcine and murine brain tissue slices obtained with a vibratome.

    PubMed

    Mattei, G; Cristiani, I; Magliaro, C; Ahluwalia, A

    2015-01-01

    This study is aimed at characterizing soft tissue slices using a vibratome. In particular, the effect of two sectioning parameters (i.e., step size and sectioning speed) on resultant slice thickness was investigated for fresh porcine liver as well as for paraformaldehyde-fixed (PFA-fixed) and fresh murine brain. A simple framework for embedding, sectioning and imaging the slices was established to derive their thickness, which was evaluated through a purposely developed graphical user interface. Sectioning speed and step size had little effect on the thickness of fresh liver slices. Conversely, the thickness of PFA-fixed murine brain slices was found to be dependent on the step size, but not on the sectioning speed. In view of these results, fresh brain tissue was sliced varying the step size only, which was found to have a significant effect on resultant slice thickness. Although precision-cut slices (i.e., with regular thickness) were obtained for all the tissues, slice accuracy (defined as the match between the nominal step size chosen and the actual slice thickness obtained) was found to increase with tissue stiffness from fresh liver to PFA-fixed brain. This quantitative investigation can be very helpful for establishing the most suitable slicing setup for a given tissue. PMID:25945319

  7. Profile analysis of hepatic porcine and murine brain tissue slices obtained with a vibratome

    PubMed Central

    Mattei, G; Cristiani, I; Magliaro, C

    2015-01-01

    This study is aimed at characterizing soft tissue slices using a vibratome. In particular, the effect of two sectioning parameters (i.e., step size and sectioning speed) on resultant slice thickness was investigated for fresh porcine liver as well as for paraformaldehyde-fixed (PFA-fixed) and fresh murine brain. A simple framework for embedding, sectioning and imaging the slices was established to derive their thickness, which was evaluated through a purposely developed graphical user interface. Sectioning speed and step size had little effect on the thickness of fresh liver slices. Conversely, the thickness of PFA-fixed murine brain slices was found to be dependent on the step size, but not on the sectioning speed. In view of these results, fresh brain tissue was sliced varying the step size only, which was found to have a significant effect on resultant slice thickness. Although precision-cut slices (i.e., with regular thickness) were obtained for all the tissues, slice accuracy (defined as the match between the nominal step size chosen and the actual slice thickness obtained) was found to increase with tissue stiffness from fresh liver to PFA-fixed brain. This quantitative investigation can be very helpful for establishing the most suitable slicing setup for a given tissue. PMID:25945319

  8. Slicing black hole spacetimes

    NASA Astrophysics Data System (ADS)

    Bini, Donato; Bittencourt, Eduardo; Geralico, Andrea; Jantzen, Robert T.

    2015-04-01

    A general framework is developed to investigate the properties of useful choices of stationary spacelike slicings of stationary spacetimes whose congruences of timelike orthogonal trajectories are interpreted as the world lines of an associated family of observers, the kinematical properties of which in turn may be used to geometrically characterize the original slicings. On the other hand, properties of the slicings themselves can directly characterize their utility motivated instead by other considerations like the initial value and evolution problems in the 3-plus-1 approach to general relativity. An attempt is made to categorize the various slicing conditions or "time gauges" used in the literature for the most familiar stationary spacetimes: black holes and their flat spacetime limit.

  9. The Virtual Slice Setup

    PubMed Central

    Lytton, William W; Neymotin, Samuel A; Hines, Michael L

    2008-01-01

    In an effort to design a simulation environment that is more similar to that of neurophysiology, we introduce a virtual slice setup in the NEURON simulator. The virtual slice setup runs continuously and permits parameter changes including changes to synaptic weights and time course and to intrinsic cell properties. The virtual slice setup permits shocks to be applied at chosen locations and activity to be sampled intra- or extracellularly from chosen locations. By default, a summed population display is shown during a run to indicate the level of activity and no states are saved. Simulations can run for hours of model time, therefore it is not practical to save all of the state variables which in any case are primarily of interest at discrete times when experiments are being run: the simulation can be stopped momentarily at such times to save activity patterns. The virtual slice setup maintains an automated notebook showing shocks and parameter changes as well as user comments. We demonstrate how interaction with a continuously running simulation encourages experimental prototyping and can suggest additional dynamical features such as ligand wash-in and wash-out – alternatives to typical instantaneous parameter change. The virtual slice setup currently uses event-driven cells and runs at approximately 2 minutes/hour on a laptop. PMID:18452996

  10. LSA Large Area Silicon Sheet Task Enhanced I.D. Slicing Technology for Silicon Ingots

    NASA Technical Reports Server (NTRS)

    Walters, D.

    1979-01-01

    Development of inside diameter slicing technology to significantly increase the number of useable slices per inch of crystal over industry practice is discussed. The required reduction of both blade and slice thickness is to be accomplished by a combination of three key elements of slicing technology: (1) ingot rotation with minimum exposed blade area; (2) dynamic cutting edge control; and (3) the use of prefabricated insert blades. Design modifications on a slicing saw with microprocessor controls and hardware fabrication to complete this conversion were initiated. Several runs were conducted on the engineering saw incorporating the method of ingot rotation. Ingots with diameters up to six inches were sliced successfully on a production saw.

  11. Planetary brightness temperature measurements at 8.6 mm and 3.1 mm wavelengths.

    NASA Technical Reports Server (NTRS)

    Ulich, B. L.; Cogdell, J. R.; Davis, J. H.

    1973-01-01

    New measurements of the sun, moon, Mercury, Venus, Mars, Jupiter, and Saturn at 3.1- and 8.6-mm wavelengths are given. The temperatures reported for the planets at 3.1-mm wavelength are higher than previous measurements in this wavelength range and change the interpretation of some planetary spectra. For Mercury, it is found that the mean brightness temperature is independent of wavelength and that a temperature-dependent thermal conductivity is not required to match the observations. In the case of Mars, the spectrum is shown to rise in the millimeter region, as simple models predict. For Jupiter, the need to recalculate the spectrum with recent models is demonstrated. The flux density scale proposed by Dent (1972) has been revised according to a more accurate determination of the millimeter brightness temperature of Jupiter.

  12. EEG source analysis of epileptiform activity using a 1mm anisotropic hexahedra finite element head model

    PubMed Central

    Rullmann, M.; Anwander, A.; Dannhauer, M.; Warfield, S.K.; Duffy, F.H.; Wolters, C.H.

    2009-01-01

    The major goal of the evaluation in presurgical epilepsy diagnosis for medically intractable patients is the precise reconstruction of the epileptogenic foci, preferably with non-invasive methods. This paper evaluates whether surface electroencephalography (EEG) source analysis based on a 1mm anisotropic finite element (FE) head model can provide additional guidance for presurgical epilepsy diagnosis and whether it is practically feasible in daily routine. A 1mm hexahedra FE volume conductor model of the patient’s head with special focus on accurately modeling the compartments skull, cerebrospinal fluid (CSF) and the anisotropic conducting brain tissues was constructed using non-linearly co-registered T1-, T2- and diffusion-tensor- magnetic resonance imaging data. The electrodes of intra-cranial EEG (iEEG) measurements were extracted from a co-registered computed tomography image. Goal function scan (GFS), minimum norm least squares (MNLS), standardized low resolution electromagnetic tomography (sLORETA) and spatio-temporal current dipole modeling inverse methods were then applied to the peak of the averaged ictal discharges EEG data. MNLS and sLORETA pointed to a single center of activity. Moving and rotating single dipole fits resulted in an explained variance of more than 97%. The non-invasive EEG source analysis methods localized at the border of the lesion and at the border of the iEEG electrodes which mainly received ictal discharges. Source orientation was towards the epileptogenic tissue. For the reconstructed superficial source, brain conductivity anisotropy and the lesion conductivity had only a minor influence, whereas a correct modeling of the highly conducting CSF compartment and the anisotropic skull was found to be important. The proposed FE forward modeling approach strongly simplifies meshing and reduces run-time (37 Milliseconds for one forward computation in the model with 3.1 Million unknowns), corroborating the practical feasibility of the

  13. Rapid ultrathin slice plastination of embalmed specimens with minimal tissue loss.

    PubMed

    Soal, S; Pollard, M; Burland, G; Lissaman, R; Wafer, M; Stringer, M D

    2010-07-01

    A modified technique of producing 1 mm (ultrathin) E12 plastinated slices of tissue specimens from embalmed cadavers for anatomical teaching and research is described. Specimens up to 150 mm in length and width were embedded in polyurethane foam and serially sectioned using an OMAS C300 food slicer. Individual slices were then processed by cold dehydration, degreasing, resin impregnation, mounting and curing. Bone-containing specimens were first decalcified. Tissue slices could be cut with remarkable accuracy (0.98 +/- 0.01 mm per slice) and minimal tissue loss (less than 2% per slice). The entire production process could be achieved in 25 days and was associated with tissue volume shrinkage of no more than 6%. These results demonstrate a relatively rapid method of producing ultrathin E12 slices with minimal tissue loss. The technique may be particularly applicable to submacroscopic morphologic studies and three-dimensional reconstruction in clinical anatomy. PMID:20235170

  14. Slice of Comet Dust

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image illustrates one of several ways scientists have begun extracting comet particles from the Stardust spacecraft's collector. First, a particle and its track are cut out of the collector material, called aerogel, in a wedge-shaped slice called a keystone. A specialized silicon pickle fork is then used to remove the keystone from the remaining aerogel for further analysis.

  15. Multilayer PDMS microfluidic chamber for controlling brain slice microenvironment

    PubMed Central

    Blake, A. J.; Pearce, T. M.; Rao, N. S.; Johnson, S. M.; Williams, J. C.

    2008-01-01

    A novel three-layer microfluidic polydimethylsiloxane (PDMS) device was constructed with two fluid chambers that holds a brain slice in place with microposts while maintaining laminar perfusate flow above and below the slice. Our fabrication technique permits rapid production of PDMS layers that can be applied to brain slices of different shapes and sizes. In this study, the device was designed to fit the shape and thickness (530-700 μm) of a medullary brain slice taken from P0-P4 neonatal rats. Medullary slices in this chamber spontaneously produced rhythmic, respiratory-related motor output for up to 3 h, thereby demonstrating that brain slice viability was maintained for prolonged periods. This design is unique in that it achieves independent control of fluids through multiple channels in two separate fluid chambers. The laminar flow exhibited by the microfluidic chamber allows controlled solutions to target specific areas of the brain slice based on the input flow rates. To demonstrate this capability, a stream of Na+-free solution was focused on one half of a medullary slice to abolish spontaneous neural activity in only that half of the brain slice, while the other half remained active. We also demonstrated that flow of different solutions can be focused over the midline of the brain slice. The multilayer brain slice chamber design can integrate several traditional types of electrophysiology tools that are commonly used to measure neurophysiological properties of brain slices. Thus, this new microfluidic chamber is advantageous for experiments that involve controlled drug or solution delivery at high spatiotemporal resolution. PMID:17594002

  16. Toward 1-mm depth precision with a solid state full-field range imaging system

    NASA Astrophysics Data System (ADS)

    Dorrington, Adrian A.; Carnegie, Dale A.; Cree, Michael J.

    2006-02-01

    Previously, we demonstrated a novel heterodyne based solid-state full-field range-finding imaging system. This system is comprised of modulated LED illumination, a modulated image intensifier, and a digital video camera. A 10 MHz drive is provided with 1 Hz difference between the LEDs and image intensifier. A sequence of images of the resulting beating intensifier output are captured and processed to determine phase and hence distance to the object for each pixel. In a previous publication, we detailed results showing a one-sigma precision of 15 mm to 30 mm (depending on signal strength). Furthermore, we identified the limitations of the system and potential improvements that were expected to result in a range precision in the order of 1 mm. These primarily include increasing the operating frequency and improving optical coupling and sensitivity. In this paper, we report on the implementation of these improvements and the new system characteristics. We also comment on the factors that are important for high precision image ranging and present configuration strategies for best performance. Ranging with sub-millimeter precision is demonstrated by imaging a planar surface and calculating the deviations from a planar fit. The results are also illustrated graphically by imaging a garden gnome.

  17. Integrated intravascular ultrasound and optical-resolution photoacoustic microscopy with a 1-mm-diameter catheter

    NASA Astrophysics Data System (ADS)

    Bai, Xiaosong; Gong, Xiaojing; Lin, Riqiang; Hau, William; Song, Liang

    2014-03-01

    Intravascular ultrasound (IVUS) plays a vital role in assessing the severity of atherosclerosis and has greatly enriched our knowledge on atherosclerotic plaques. However, it mainly reveals the structural information of plaques. In contrast, spectroscopic and molecular photoacoustic imaging can potentially improve plaque composition identification, inflammation detection, and ultimately the stratification of plaque vulnerability and risk. In this work, we developed an integrated intravascular ultrasound and optical-resolution photoacoustic microscopy (IVUS-PAM) system with a single catheter as small as 1 mm in diameter, comparable to that of existing clinical IVUS catheters. In addition, by using a GRIN lens to focus the excitation laser pulse, the system provides an optical-diffraction limited photoacoustic lateral resolution as fine as 19.6 micrometers, ~10-fold finer than that of conventional intravascular photoacoustic imaging and existing IVUS technology. The system employs a custom-made miniaturized single-element ultrasonic transducer with a dimension of ~0.5 mm, a centre frequency of ~40 MHz, and a fractional bandwidth of ~60%. The IVUS-PAM can simultaneously acquire co-registered IVUS images with an axial resolution of ~40 micrometers and a lateral resolution of ~200 micrometers. In the future, IVUS-PAM may open up new opportunities for improved high-resolution vulnerable plaque imaging and image-guided stent deployment.

  18. Portable Device Slices Thermoplastic Prepregs

    NASA Technical Reports Server (NTRS)

    Taylor, Beverly A.; Boston, Morton W.; Wilson, Maywood L.

    1993-01-01

    Prepreg slitter designed to slit various widths rapidly by use of slicing bar holding several blades, each capable of slicing strip of preset width in single pass. Produces material evenly sliced and does not contain jagged edges. Used for various applications in such batch processes involving composite materials as press molding and autoclaving, and in such continuous processes as pultrusion. Useful to all manufacturers of thermoplastic composites, and in slicing B-staged thermoset composites.

  19. Meta-Analysis of Sentinel Lymph Node Positivity in Thin Melanoma (≤ 1 mm)

    PubMed Central

    Warycha, Melanie A.; Zakrzewski, Jan; Ni, Quanhong; Shapiro, Richard L.; Berman, Russell S.; Pavlick, Anna C.; Polsky, David; Mazumdar, Madhu; Osman, Iman

    2014-01-01

    Background Despite the lack of an established survival benefit of sentinel lymph node (SLN) biopsy, this technique has been increasingly applied in the staging of thin (≤1 mm) melanoma patients, without clear evidence to support this recommendation. We performed a meta-analysis to estimate the risk, potential predictors, and outcome of SLN positivity in this group of patients. Methods MEDLINE, EMBASE, and Cochrane databases were searched for rates of SLN positivity in patients with thin melanoma. The methodological quality of included studies was assessed using the MINORS criteria. Heterogeneity was assessed using Cochran’s Q-statistic, and publication bias was examined through funnel plot and Begg and Mazumdar’s method. Overall SLN positivity in thin melanoma patients was estimated using DerSimonial-Laird random effect method. Results 34 studies comprising 3,651 patients met inclusion criteria. The pooled SLN positivity rate was 5.6%. Significant heterogeneity among studies was detected (p=0.005). There was no statistical evidence of publication bias (p=0.21). 18 studies reported select clinical and histopathologic data limited to SLN positive patients (n=113). Among the tumors from these patients, 6.1% were ulcerated, 31.5% showed regression, and 47.5% were Clark’s level IV/V. Only 4 melanoma-related deaths were reported. Conclusion Relatively few patients with thin melanoma have a positive SLN. There are no clinical or histopathologic criteria which can reliably identify thin melanoma patients who might benefit from this intervention. Given the increasing diagnosis of thin melanoma, in addition to the cost and potential morbidity of this procedure, alternative strategies to identify patients at risk for nodal disease are needed. PMID:19117354

  20. Slice profile distortions in single slice continuously moving table MRI

    NASA Astrophysics Data System (ADS)

    Sengupta, Saikat; Smith, David S.; Welch, E. B.

    2015-03-01

    Continuously Moving Table (CMT) MRI is a rapid imaging technique that allows scanning of extended fields of view (FOVs) such as the whole-body in a single continuous scan.1 A highly efficient approach to CMT MRI is single slice imaging, where data are continuously acquired from a single axial slice at isocenter with concurrent movement of the patient table.2 However, the continuous motion of the scanner table and supply of fresh magnetization into the excited slice can introduce deviations in the slice magnetization profile. The goal of this work is to investigate and quantify the distortion in the slice profile in CMT MRI. CMT MRI with a table speed of 20 mm/s was implemented on a 3 Tesla whole-body MRI scanner, with continuous radial data acquisition. Simulations were performed to characterize the transient and steady state slice profiles and magnetization effects. Simulated slice profiles were compared to actual slice profile measurements performed in the scanner. Both simulations and experiments revealed an asymmetric slice profile characterized by a skew towards the lagging edge of the moving table, in contrast to the nominal profiles associated with scanning a stationary object. The true excited slice width (FWHM) and pitch of the acquisition was observed to be dependent on table velocity, with larger table speeds resulting in larger slice profile deviations from the nominal shape.

  1. Flash lamp light slicing

    NASA Astrophysics Data System (ADS)

    Saber, A. J.; Abdel-Wahab, T.; Georgallis, M.

    A light slicing system using a short-arc-length high-power flashlamp as the source is discussed, with application to the observation of fluid phenomena such as gas discharge and fuel injection into engines. The geometrical optics of the method, in addition to the attenuation of luminous intensity in the system, is considered, and varying the relative radius of curvature of the cylindrical lens with respect to the width of the laser beam is shown to change the extension of the light sheet lamina. Light slice system generation using CAD is discussed, and experimental results of the observation of pulsed gas discharges in a small scale valve system designed to simulate large-scale dispersion and mixing of gases in air are reported.

  2. AzTEC/ASTE 1.1 mm Deep Surveys: Number Counts and Clustering of Millimeter-bright Galaxies

    NASA Astrophysics Data System (ADS)

    Hatsukade, B.; Kohno, K.; Aretxaga, I.; Austermann, J. E.; Ezawa, H.; Hughes, D. H.; Ikarashi, S.; Iono, D.; Kawabe, R.; Matsuo, H.; Matsuura, S.; Nakanishi, K.; Oshima, T.; Perera, T.; Scott, K. S.; Shirahata, M.; Takeuchi, T. T.; Tamura, Y.; Tanaka, K.; Tosaki, T.; Wilson, G. W.; Yun, M. S.

    2010-10-01

    We present number counts and clustering properties of millimeter-bright galaxies uncovered by the AzTEC camera mounted on the Atacama Submillimeter Telescope Experiment (ASTE). We surveyed the AKARI Deep Field South (ADF-S), the Subaru/XMM Newton Deep Field (SXDF), and the SSA22 fields with an area of ~0.25 deg2 each with an rms noise level of ~0.4-1.0 mJy. We constructed differential and cumulative number counts, which provide currently the tightest constraints on the faint end. The integration of the best-fit number counts in the ADF-S find that the contribution of 1.1 mm sources with fluxes >=1 mJy to the cosmic infrared background (CIB) at 1.1 mm is 12-16%, suggesting that the large fraction of the CIB originates from faint sources of which the number counts are not yet constrained. We estimate the cosmic star-formation rate density contributed by 1.1 mm sources with >=1 mJy using the best-fit number counts in the ADF-S and find that it is lower by about a factor of 5-10 compared to those derived from UV/optically-selected galaxies at z~2-3. The average mass of dark halos hosting bright 1.1 mm sources was calculated to be 1013-1014 Msolar. Comparison of correlation lengths of 1.1 mm sources with other populations and with a bias evolution model suggests that dark halos hosting bright 1.1 mm sources evolve into systems of clusters at present universe and the 1.1 mm sources residing the dark halos evolve into massive elliptical galaxies located in the center of clusters.

  3. The theory of interface slicing

    NASA Technical Reports Server (NTRS)

    Beck, Jon

    1993-01-01

    Interface slicing is a new tool which was developed to facilitate reuse-based software engineering, by addressing the following problems, needs, and issues: (1) size of systems incorporating reused modules; (2) knowledge requirements for program modification; (3) program understanding for reverse engineering; (4) module granularity and domain management; and (5) time and space complexity of conventional slicing. The definition of a form of static program analysis called interface slicing is addressed.

  4. Combined infrared-vacuum drying of pumpkin slices.

    PubMed

    Ghaboos, Seyyed Hossein Hosseini; Ardabili, Seyed Mahdi Seyedain; Kashaninejad, Mahdi; Asadi, Gholamhassan; Aalami, Mehran

    2016-05-01

    Infrared-vacuum dehydration characteristics of pumpkin (Cucurbita moschata) were evaluated in a combined dryer system. The effects of drying parameters, infrared radiation power (204-272 W), system pressure (5-15 kPa), slice thickness (5 and 7 mm) and time (0-220 min) on the drying kinetics and characteristics of pumpkin slices were investigated. The vacuum pressure, lamp power and slice had significant effect on the drying kinetics and various qualities of the dried pumpkin. Moisture ratios were fitted to 10 different mathematical equations using nonlinear regression analysis. The quadratic equation satisfactorily described the drying behavior of pumpkin slices with the highest r value and the lowest SE values. The effective moisture diffusivity increased with power and ranged between 0.71 and 2.86 × 10(-9) m(2)/s. With increasing in infrared radiation power from 204 to 272 W, β-carotene content of dried pumpkins decreased from 30.04 to 24.55 mg/100 g. The rise in infrared power has a negative effect on the color changes (ΔE). The optimum condition was determined as power, 238W, pressure, 5 kPa and slice thickness, 5mm. These conditions resulted into dried pumpkin slices with maximum B-carotene retention. PMID:27407204

  5. Diffusion of radiotracers in normal and ischemic brain slices.

    PubMed

    Patlak, C S; Hospod, F E; Trowbridge, S D; Newman, G C

    1998-07-01

    Diffusion in the extracellular space (ECS) is important in physiologic and pathologic brain processes but remains poorly understood. To learn more about factors influencing tissue diffusion and the role of diffusion in solute-tissue interactions, particularly during cerebral ischemia, we have studied the kinetics of several radiotracers in control and hypoxic 450-microm hippocampal slices and in 1,050-microm thick slices that model the ischemic penumbra. Kinetics were analyzed by nonlinear least squares methods using models that combine extracellular diffusion with tissue compartments in series or in parallel. Studies with 14C-polyethylene glycol confirmed prior measurements of extracellular volume and that ECS shrinks during ischemia. Separating diffusion from transport also revealed large amounts of 45Ca that bind to or enter brain as well as demonstrating a small, irreversibly bound compartment during ischemia. The rapidity of 3H2O entry into cells made it impossible for us to distinguish intracellular from extracellular diffusion. The diffusion-compartment analysis of 3-O-methylglucose data appears to indicate that 5 mmol/L glucose is inadequate to support glycolysis fully in thick slices. Unexpectedly, the diffusion coefficient for all four tracers rose in thick slices compared with thin slices, suggesting that ECS becomes less tortuous in the penumbra. PMID:9663508

  6. Radiation phantom with humanoid shape and adjustable thickness

    DOEpatents

    Lehmann, Joerg; Levy, Joshua; Stern, Robin L.; Siantar, Christine Hartmann; Goldberg, Zelanna

    2006-12-19

    A radiation phantom comprising a body with a general humanoid shape and at least a portion having an adjustable thickness. In one embodiment, the portion with an adjustable thickness comprises at least one tissue-equivalent slice.

  7. Cardiac tissue slices: preparation, handling, and successful optical mapping.

    PubMed

    Wang, Ken; Lee, Peter; Mirams, Gary R; Sarathchandra, Padmini; Borg, Thomas K; Gavaghan, David J; Kohl, Peter; Bollensdorff, Christian

    2015-05-01

    Cardiac tissue slices are becoming increasingly popular as a model system for cardiac electrophysiology and pharmacology research and development. Here, we describe in detail the preparation, handling, and optical mapping of transmembrane potential and intracellular free calcium concentration transients (CaT) in ventricular tissue slices from guinea pigs and rabbits. Slices cut in the epicardium-tangential plane contained well-aligned in-slice myocardial cell strands ("fibers") in subepicardial and midmyocardial sections. Cut with a high-precision slow-advancing microtome at a thickness of 350 to 400 μm, tissue slices preserved essential action potential (AP) properties of the precutting Langendorff-perfused heart. We identified the need for a postcutting recovery period of 36 min (guinea pig) and 63 min (rabbit) to reach 97.5% of final steady-state values for AP duration (APD) (identified by exponential fitting). There was no significant difference between the postcutting recovery dynamics in slices obtained using 2,3-butanedione 2-monoxime or blebistatin as electromechanical uncouplers during the cutting process. A rapid increase in APD, seen after cutting, was caused by exposure to ice-cold solution during the slicing procedure, not by tissue injury, differences in uncouplers, or pH-buffers (bicarbonate; HEPES). To characterize intrinsic patterns of CaT, AP, and conduction, a combination of multipoint and field stimulation should be used to avoid misinterpretation based on source-sink effects. In summary, we describe in detail the preparation, mapping, and data analysis approaches for reproducible cardiac tissue slice-based investigations into AP and CaT dynamics. PMID:25595366

  8. Cardiac tissue slices: preparation, handling, and successful optical mapping

    PubMed Central

    Wang, Ken; Lee, Peter; Mirams, Gary R.; Sarathchandra, Padmini; Borg, Thomas K.; Gavaghan, David J.; Kohl, Peter

    2015-01-01

    Cardiac tissue slices are becoming increasingly popular as a model system for cardiac electrophysiology and pharmacology research and development. Here, we describe in detail the preparation, handling, and optical mapping of transmembrane potential and intracellular free calcium concentration transients (CaT) in ventricular tissue slices from guinea pigs and rabbits. Slices cut in the epicardium-tangential plane contained well-aligned in-slice myocardial cell strands (“fibers”) in subepicardial and midmyocardial sections. Cut with a high-precision slow-advancing microtome at a thickness of 350 to 400 μm, tissue slices preserved essential action potential (AP) properties of the precutting Langendorff-perfused heart. We identified the need for a postcutting recovery period of 36 min (guinea pig) and 63 min (rabbit) to reach 97.5% of final steady-state values for AP duration (APD) (identified by exponential fitting). There was no significant difference between the postcutting recovery dynamics in slices obtained using 2,3-butanedione 2-monoxime or blebistatin as electromechanical uncouplers during the cutting process. A rapid increase in APD, seen after cutting, was caused by exposure to ice-cold solution during the slicing procedure, not by tissue injury, differences in uncouplers, or pH-buffers (bicarbonate; HEPES). To characterize intrinsic patterns of CaT, AP, and conduction, a combination of multipoint and field stimulation should be used to avoid misinterpretation based on source-sink effects. In summary, we describe in detail the preparation, mapping, and data analysis approaches for reproducible cardiac tissue slice-based investigations into AP and CaT dynamics. PMID:25595366

  9. Trumpet slices in Kerr spacetimes.

    PubMed

    Dennison, Kenneth A; Baumgarte, Thomas W; Montero, Pedro J

    2014-12-31

    We introduce a new time-independent family of analytical coordinate systems for the Kerr spacetime representing rotating black holes. We also propose a (2+1)+1 formalism for the characterization of trumpet geometries. Applying this formalism to our new family of coordinate systems we identify, for the first time, analytical and stationary trumpet slices for general rotating black holes, even for charged black holes in the presence of a cosmological constant. We present results for metric functions in this slicing and analyze the geometry of the rotating trumpet surface. PMID:25615297

  10. Scanning fiber endoscopy with highly flexible, 1-mm catheterscopes for wide-field, full-color imaging

    PubMed Central

    Lee, Cameron M.; Engelbrecht, Christoph J.; Soper, Timothy D.; Helmchen, Fritjof; Seibel, Eric J.

    2011-01-01

    In modern endoscopy, wide field of view and full color are considered necessary for navigating inside the body, inspecting tissue for disease and guiding interventions such as biopsy or surgery. Current flexible endoscope technologies suffer from reduced resolution when device diameter shrinks. Endoscopic procedures today using coherent fiber bundle technology, on the scale of 1 mm, are performed with such poor image quality that the clinician’s vision meets the criteria for legal blindness. Here, we review a new and versatile scanning fiber imaging technology and describe its implementation for ultrathin and flexible endoscopy. This scanning fiber endoscope (SFE) or catheterscope enables high quality, laser-based, video imaging for ultrathin clinical applications while also providing new options for in vivo biological research of subsurface tissue and high resolution fluorescence imaging. PMID:20336702

  11. Continuum observations of M 51 and M 83 at 1.1 mm with AzTEC

    NASA Astrophysics Data System (ADS)

    Wall, W. F.; Puerari, I.; Tilanus, R.; Israel, F. P.; Austermann, J. E.; Aretxaga, I.; Wilson, G.; Yun, M.; Scott, K. S.; Perera, T. A.; Roberts, C. M.; Hughes, D. H.

    2016-06-01

    We observed the spiral galaxies M 51 and M 83 at 20 arscec spatial resolution with the bolometer array Aztronomical Thermal Emission Camera (AzTEC) on the JCMT in the 1.1 mm continuum, recovering the extended emission out to galactocentric radii of more than 12 kpc in both galaxies. The 1.1 mm-continuum fluxes are 5.6 ± 0.7 and 9.9 ± 1.4 Jy, with associated gas masses estimated at 9.4 × 109 M⊙ and 7.2 × 109 M⊙ for M 51 and M 83, respectively. In the interarm regions of both galaxies, the N(H2)/I(CO) (or X-factor) ratios exceed those in the arms by factors of ˜1.5-2. In the inner discs of both galaxies, the X-factor is about 1 × 1020 cm- 2 (K km s- 1)- 1. In the outer parts, the CO-dark molecular gas becomes more important. While the spiral density wave in M 51 appears to influence the interstellar medium and stars in a similar way, the bar potential in M 83 influences the interstellar medium and the stars differently. We confirm the result of Foyle et al. that the arms merely heighten the star formation rate (SFR) and the gas surface density in the same proportion. Our maps reveal a threshold gas surface density for an SFR increase by two or more orders of magnitude. In both galaxy centres, the molecular gas depletion time is about 1 Gyr climbing to 10-20 Gyr at radii of 6-8 kpc. This is consistent with an inside-out depletion of the molecular gas in the discs of spiral galaxies.

  12. Effect of oxygen pressure on glycogen synthesis by rat-liver slices

    PubMed Central

    Figueroa, Enrique; Vallejos, Rodolfo; Pfeifer, Ariana; Kahler, Cecilia

    1966-01-01

    1. Glycogen synthesized by rat-liver slices 0·5mm. thick incubated at 1atm. oxygen pressure in Hastings medium with glucose was localized in the cells of the periphery of the slice. Cells of the interior of this slice do not synthesize glycogen. 2. Inner cells of thin slices (about 0·3mm. thick) can synthesize glycogen when such slices are incubated under the same conditions, but oxygen pressures higher than 1atm. are required if inner cells of slices 0·5mm. or more thick are to be able to synthesize glycogen. 3. Localization of newly synthesized glycogen in rat-liver slices incubated in Hastings medium with glucose does not depend on glucose concentration. 4. Calculation of the minimum oxygen pressure required to synthesize glycogen gives values between 0·09 and 0·17atm. 5. The advantages of high oxygen pressures for the study of the synthesis of glycogen and other compounds that require ATP are discussed. ImagesFig. 2.Fig. 5. PMID:5938650

  13. Urea Biosynthesis Using Liver Slices

    ERIC Educational Resources Information Center

    Teal, A. R.

    1976-01-01

    Presented is a practical scheme to enable introductory biology students to investigate the mechanism by which urea is synthesized in the liver. The tissue-slice technique is discussed, and methods for the quantitative analysis of metabolites are presented. (Author/SL)

  14. Detecting 1mm/Year Signals in Altimetric Global Sea Level: Effect of Atmospheric Water Vapor and Precipitation

    NASA Technical Reports Server (NTRS)

    Zlotnicki, Victor

    1999-01-01

    Several research efforts exist to use Topography Experiment (TOPEX)/ Projet d'Observatorie de Surveillance et d'Etudes Integrees de la Dynamique des Oceans (Poseidon) (T/P) to detect changes in global sea level possibly associated with climate change. This requires much better than 1 mm/yr accuracy, something that none of the instruments in T/P [or the European Remote Sensing (ERS-2) satellite, or the U.S. Navy's Geosat Follow-On (GFO) satellite] were designed for. This work focuses on the ability of the T/P microwave radiometer (TMR) to retrieve the path delay due to atmospheric water vapor along the altimeter's path with accuracy in the time changes below 1 mm/yr on global average. In collaboration with Stephen Keihm of JPL and Christopher Ruf of Pennsylvania State University, we compared TMR path delay (PD) estimates with atmospheric precipitable water (PW) from the Special Sensor Microwave Imager (SSMI) aboard the Defense Meteorological Satellite Program (DMSP) series of satellites for 1992-1998 to selected radiosondes, and we also looked at the brightness temperatures measured by TMR in the lowest 1% of the histogram. The conclusion is that TMR had a slow instrumental drift, associated with the 18-GHz channel, which causes an approximate underestimation of water vapor at a rate equivalent to 1.2 mm/yr in path delay between 1992 and 1996; this effect stopped and no drift is detected in 1997. The same study concluded that there is no detectable scale error (one which is proportional to measured vapor) in TMR. In related work, carried out with graduate student Damien Cailliau, we investigated the relative abilities of TMR, SSMI and the UP dual-frequency radar altimeter to detect rain, relative to a climatology of shipborne observations. Rain is a crucial but poorly measured variable in studies of the climate system, and a dedicated mission, Tropical Rainfall Measuring Mission (TRMM), was recently launched to measure it. However, the climatologies built over the

  15. Wire blade development for Fixed Abrasive Slicing Technique (FAST) slicing

    NASA Technical Reports Server (NTRS)

    Khattak, C. P.; Schmid, F.; Smith, M. B.

    1982-01-01

    A low cost, effective slicing method is essential to make ingot technology viable for photovoltaics in terrestrial applications. The fixed abrasive slicing technique (FAST) combines the advantages of the three commercially developed techniques. In its development stage FAST demonstrated cutting effectiveness of 10 cm and 15 cm diameter workpieces. Wire blade development is still the critical element for commercialization of FAST technology. Both impregnated and electroplated wire blades have been developed; techniques have been developed to fix diamonds only in the cutting edge of the wire. Electroplated wires show the most near term promise and this approach is emphasized. With plated wires it has been possible to control the size and shape of the electroplating, it is expected that this feature reduces kerf and prolongs the life of the wirepack.

  16. Surface-micromachined magnetic undulator with period length between 10μm and 1 mm for advanced light sources

    NASA Astrophysics Data System (ADS)

    Harrison, Jere; Joshi, Abhijeet; Lake, Jonathan; Candler, Rob; Musumeci, Pietro

    2012-07-01

    A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15μm. Simulations indicate that magnetic fields as large as 1.5 T across 50μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  17. The Arizona Radio Observatory 1 mm Spectral Survey of IRC (plus)10216 and VY Canis Majoris (215-285 GHz)

    NASA Technical Reports Server (NTRS)

    Tenenbaum, E. D.; Dodd, J. L.; Milam, S. N.; Woolf, N. J.; Ziurys, L. M.

    2010-01-01

    A low noise (1(sigma) rms approx. 3 mK) 1. nun spectral survey (214.5-285.5 GHz) of the oxygen-rich supergiant VY Canis Majoris and the carbon-rich asymptotic giant branch star IRC +10216 has been conducted using the Arizona Radio Observatory's 10 m Submillimeter Telescope. Here the complete data set is presented. This study, carried out with a new ALMA-type receiver, marks the first continuous band scan of an O-rich circumstellar envelope, and the most sensitive survey to date of IRC +10216. In VY CMa, 130 distinct molecular lines were detected, 14 of which cannot be identified; in IRC +10216, 717 lines were observed, with 126 features remaining unidentified. In the 1 mm bands of VY CMa and IRC +10216, emission is present from 18 and 32 different chemical compounds, respectively, with 10 species common to both sources. Many narrow emission lines were observed in both circumstellar shells, arising from vibrationally excited molecules and from refractory-containing species. Line profiles in VY CMa also exhibit a variety of different shapes, caused by the complex, asymmetric outflow of this object. The survey highlights the fact that C-rich and O-rich circumstellar envelopes are chemically interesting, and both are sources of new interstellar molecules. The high number of unidentified lines and the unreliable, rest frequencies for known species such as NaCN indicate the need for additional laboratory spectroscopy studies.

  18. Influence of cement type and thickness on polyfiber post adhesion

    PubMed Central

    Uzunoğlu, Emel; Türker, Sevinç Aktemur; Yilmaz, Zeliha

    2014-01-01

    Introduction: To evaluate the effect of two different post space diameters and related resin cement film thicknesses on the bond strength of a polyfiber post. Materials and Methods: A total of 48 premolars were randomly divided into two according to the post space diameter: 1.1 mm and 1.5 mm. Then each group was divided into three sub-groups according to luting cement used: RelyX U100, Panavia F2.0/ED primer, Clearfil SA cement. Spirapost was then luted into the canal using luting cements. Two slices were obtained from each root specimen. Push-out tests were performed. Data was analyzed with Kruskal-Wallis and Connover post-hoc and Mann-Whitney U-test (P < 0.05). Results: Push-out bond strength was found to vary significantly according to type of adhesive system and post space diameter size (P < 0.05). The self-adhesive resin cement RelyX U100 had significantly higher bond strengths compared with the other adhesive system (P < 0.05). The self-etch adhesive system (Panavia F2.0) showed significantly lower bond strengths compared with the other systems (P < 0.05). There was a significant interaction between the luting systems and post space diameter (P < 0.05). Conclusion: The increases in post space diameter significantly reduced the bond strength of Spirapost to root dentine for both groups. PMID:24944450

  19. Ingot slicing machine and method

    NASA Technical Reports Server (NTRS)

    Kuo, Y. S. (Inventor)

    1984-01-01

    An improved method for simultaneously slicing one or a multiplicity of boules of silicon into silicon wafers is described. A plurality of vertical stacks of horizontal saw blades of circular configuration are arranged in juxtaposed coaxial alignment. Each blade is characterized by having a cutting diameter slightly greater than the cutting diameter of the blade arranged immediately above, imparting a simultaneous rotation to the blades.

  20. Thermal regulation of tightly packed solid-state photodetectors in a 1 mm{sup 3} resolution clinical PET system

    SciTech Connect

    Freese, D. L.; Vandenbroucke, A.; Innes, D.; Lau, F. W. Y.; Hsu, D. F. C.; Reynolds, P. D.; Levin, Craig S.

    2015-01-15

    Purpose: Silicon photodetectors are of significant interest for use in positron emission tomography (PET) systems due to their compact size, insensitivity to magnetic fields, and high quantum efficiency. However, one of their main disadvantages is fluctuations in temperature cause strong shifts in gain of the devices. PET system designs with high photodetector density suffer both increased thermal density and constrained options for thermally regulating the devices. This paper proposes a method of thermally regulating densely packed silicon photodetectors in the context of a 1 mm{sup 3} resolution, high-sensitivity PET camera dedicated to breast imaging. Methods: The PET camera under construction consists of 2304 units, each containing two 8 × 8 arrays of 1 mm{sup 3} LYSO crystals coupled to two position sensitive avalanche photodiodes (PSAPD). A subsection of the proposed camera with 512 PSAPDs has been constructed. The proposed thermal regulation design uses water-cooled heat sinks, thermoelectric elements, and thermistors to measure and regulate the temperature of the PSAPDs in a novel manner. Active cooling elements, placed at the edge of the detector stack due to limited access, are controlled based on collective leakage current and temperature measurements in order to keep all the PSAPDs at a consistent temperature. This thermal regulation design is characterized for the temperature profile across the camera and for the time required for cooling changes to propagate across the camera. These properties guide the implementation of a software-based, cascaded proportional-integral-derivative control loop that controls the current through the Peltier elements by monitoring thermistor temperature and leakage current. The stability of leakage current, temperature within the system using this control loop is tested over a period of 14 h. The energy resolution is then measured over a period of 8.66 h. Finally, the consistency of PSAPD gain between independent

  1. Thermal regulation of tightly packed solid-state photodetectors in a 1 mm3 resolution clinical PET system

    PubMed Central

    Vandenbroucke, A.; Innes, D.; Lau, F. W. Y.; Hsu, D. F. C.; Reynolds, P. D.; Levin, Craig S.

    2015-01-01

    Purpose: Silicon photodetectors are of significant interest for use in positron emission tomography (PET) systems due to their compact size, insensitivity to magnetic fields, and high quantum efficiency. However, one of their main disadvantages is fluctuations in temperature cause strong shifts in gain of the devices. PET system designs with high photodetector density suffer both increased thermal density and constrained options for thermally regulating the devices. This paper proposes a method of thermally regulating densely packed silicon photodetectors in the context of a 1 mm3 resolution, high-sensitivity PET camera dedicated to breast imaging. Methods: The PET camera under construction consists of 2304 units, each containing two 8 × 8 arrays of 1 mm3 LYSO crystals coupled to two position sensitive avalanche photodiodes (PSAPD). A subsection of the proposed camera with 512 PSAPDs has been constructed. The proposed thermal regulation design uses water-cooled heat sinks, thermoelectric elements, and thermistors to measure and regulate the temperature of the PSAPDs in a novel manner. Active cooling elements, placed at the edge of the detector stack due to limited access, are controlled based on collective leakage current and temperature measurements in order to keep all the PSAPDs at a consistent temperature. This thermal regulation design is characterized for the temperature profile across the camera and for the time required for cooling changes to propagate across the camera. These properties guide the implementation of a software-based, cascaded proportional-integral-derivative control loop that controls the current through the Peltier elements by monitoring thermistor temperature and leakage current. The stability of leakage current, temperature within the system using this control loop is tested over a period of 14 h. The energy resolution is then measured over a period of 8.66 h. Finally, the consistency of PSAPD gain between independent operations of the

  2. Studying T Cell Development in Thymic Slices.

    PubMed

    Ross, Jenny O; Melichar, Heather J; Halkias, Joanna; Robey, Ellen A

    2016-01-01

    Recently, tissue slices have been adapted to study both mouse and human T cell development. Thymic slices combine and complement the strengths of existing organotypic culture systems to study thymocyte differentiation. Specifically, the thymic slice system allows for high throughput experiments and the ability to introduce homogenous developmental intermediate populations into an environment with a well-established cortex and medulla. These qualities make thymic slices a highly versatile and technically accessible model to study thymocyte development. Here we describe methods to prepare, embed, and slice thymic lobes to study T cell development in situ. PMID:26294404

  3. Mathematical modeling on vacuum drying of Zizyphus jujuba Miller slices.

    PubMed

    Lee, Jun Ho; Zuo, Li

    2013-02-01

    The thin-layer vacuum drying behavior of Zizyphus jujuba Miller slices was experimentally investigated at the temperature of 50, 60, and 70 °C and the mathematical models were used to fit the thin-layer vacuum drying of Z. jujuba slices. The increase in drying air temperature resulted in a decrease in drying time. The drying rate was found to increase with temperature, thereby reducing the total drying time. It was found that Z. jujuba slices with thickness of 4 mm would be dried up to 0.08 kg water/kg dry matter in the range of 180-600 min in the vacuum dryer at the studied temperature range from 70 to 50 °C. The Midilli et al. model was selected as the most appropriate model to describe the thin-layer drying of Z. jujuba slices. The diffusivity coefficient increased linearly over the temperature range from 1.47 × 10(-10) to 3.27 × 10(-10) m(2)/s, as obtained using Fick's second law. The temperature dependence of the effective diffusivity coefficient followed an Arrhenius-type relationship. The activation energy for the moisture diffusion was determined to be 36.76 kJ/mol. PMID:24425895

  4. Automatic basal slice detection for cardiac analysis

    NASA Astrophysics Data System (ADS)

    Paknezhad, Mahsa; Marchesseau, Stephanie; Brown, Michael S.

    2016-03-01

    Identification of the basal slice in cardiac imaging is a key step to measuring the ejection fraction (EF) of the left ventricle (LV). Despite research on cardiac segmentation, basal slice identification is routinely performed manually. Manual identification, however, has been shown to have high inter-observer variability, with a variation of the EF by up to 8%. Therefore, an automatic way of identifying the basal slice is still required. Prior published methods operate by automatically tracking the mitral valve points from the long-axis view of the LV. These approaches assumed that the basal slice is the first short-axis slice below the mitral valve. However, guidelines published in 2013 by the society for cardiovascular magnetic resonance indicate that the basal slice is the uppermost short-axis slice with more than 50% myocardium surrounding the blood cavity. Consequently, these existing methods are at times identifying the incorrect short-axis slice. Correct identification of the basal slice under these guidelines is challenging due to the poor image quality and blood movement during image acquisition. This paper proposes an automatic tool that focuses on the two-chamber slice to find the basal slice. To this end, an active shape model is trained to automatically segment the two-chamber view for 51 samples using the leave-one-out strategy. The basal slice was detected using temporal binary profiles created for each short-axis slice from the segmented two-chamber slice. From the 51 successfully tested samples, 92% and 84% of detection results were accurate at the end-systolic and the end-diastolic phases of the cardiac cycle, respectively.

  5. Robust reflective pupil slicing technology

    NASA Astrophysics Data System (ADS)

    Meade, Jeffrey T.; Behr, Bradford B.; Cenko, Andrew T.; Hajian, Arsen R.

    2014-07-01

    Tornado Spectral Systems (TSS) has developed the High Throughput Virtual Slit (HTVSTM), robust all-reflective pupil slicing technology capable of replacing the slit in research-, commercial- and MIL-SPEC-grade spectrometer systems. In the simplest configuration, the HTVS allows optical designers to remove the lossy slit from pointsource spectrometers and widen the input slit of long-slit spectrometers, greatly increasing throughput without loss of spectral resolution or cross-dispersion information. The HTVS works by transferring etendue between image plane axes but operating in the pupil domain rather than at a focal plane. While useful for other technologies, this is especially relevant for spectroscopic applications by performing the same spectral narrowing as a slit without throwing away light on the slit aperture. HTVS can be implemented in all-reflective designs and only requires a small number of reflections for significant spectral resolution enhancement-HTVS systems can be efficiently implemented in most wavelength regions. The etendueshifting operation also provides smooth scaling with input spot/image size without requiring reconfiguration for different targets (such as different seeing disk diameters or different fiber core sizes). Like most slicing technologies, HTVS provides throughput increases of several times without resolution loss over equivalent slitbased designs. HTVS technology enables robust slit replacement in point-source spectrometer systems. By virtue of pupilspace operation this technology has several advantages over comparable image-space slicer technology, including the ability to adapt gracefully and linearly to changing source size and better vertical packing of the flux distribution. Additionally, this technology can be implemented with large slicing factors in both fast and slow beams and can easily scale from large, room-sized spectrometers through to small, telescope-mounted devices. Finally, this same technology is directly

  6. Simulated lesion, human observer performance comparison between thin-section dedicated breast CT images versus computed thick-section simulated projection images of the breast

    PubMed Central

    Chen, L; Boone, JM; Abbey, CK; Hargreaves, J; Bateni, C; Lindfors, KK; Yang, K; Nosratieh, A; Hernandez, A; Gazi, P

    2015-01-01

    Objectives The objective of this study was to compare the lesion detection performance of human observers between thin-section computed tomography images of the breast, with thick-section (>40 mm) simulated projection images of the breast. Methods Three radiologists and six physicists each executed a two alterative force choice (2AFC) study involving simulated spherical lesions placed mathematically into breast images produced on a prototype dedicated breast CT scanner. The breast image data sets from 88 patients were used to create 352 pairs of image data. Spherical lesions with diameters of 1, 2, 3, 5, and 11 mm were simulated and adaptively positioned into 3D breast CT image data sets; the native thin section (0.33 mm) images were averaged to produce images with different slice thicknesses; average section thicknesses of 0.33 mm, 0.71 mm, 1.5 mm, and 2.9 mm were representative of breast CT; the average 43 mm slice thickness served to simulate simulated projection images of the breast. Results The percent correct of the human observer’s responses were evaluated in the 2AFC experiments. Radiologists lesion detection performance was significantly (p<0.05) better in the case of thin-section images, compared to thick section images similar to mammography, for all but the 1 mm lesion diameter lesions. For example, the average of three radiologist’s performance for 3 mm diameter lesions was 92 % correct for thin section breast CT images while it was 67 % for the simulated projection images. A gradual reduction in observer performance was observed as the section thickness increased beyond about 1 mm. While a performance difference based on breast density was seen in both breast CT and the projection image results, the average radiologist performance using breast CT images in dense breasts outperformed the performance using simulated projection images in fatty breasts for all lesion diameters except 11 mm. The average radiologist performance outperformed that of the

  7. THE BOLOCAM GALACTIC PLANE SURVEY. X. A COMPLETE SPECTROSCOPIC CATALOG OF DENSE MOLECULAR GAS OBSERVED TOWARD 1.1 mm DUST CONTINUUM SOURCES WITH 7.°5 ≤ l ≤ 194°

    SciTech Connect

    Shirley, Yancy L.; Svoboda, Brian; Ellsworth-Bowers, Timothy P.; Schlingman, Wayne M.; Ginsburg, Adam; Battersby, Cara; Stringfellow, Guy; Glenn, Jason; Bally, John; Rosolowsky, Erik; Gerner, Thomas; Mairs, Steven; Dunham, Miranda K.

    2013-11-01

    The Bolocam Galactic Plane Survey (BGPS) is a 1.1 mm continuum survey of dense clumps of dust throughout the Galaxy covering 170 deg{sup 2}. We present spectroscopic observations using the Heinrich Hertz Submillimeter Telescope of the dense gas tracers, HCO{sup +} and N{sub 2}H{sup +} 3-2, for all 6194 sources in the BGPS v1.0.1 catalog between 7.°5 ≤ l ≤ 194°. This is the largest targeted spectroscopic survey of dense molecular gas in the Milky Way to date. We find unique velocities for 3126 (50.5%) of the BGPS v1.0.1 sources observed. Strong N{sub 2}H{sup +} 3-2 emission (T {sub mb} > 0.5 K) without HCO{sup +} 3-2 emission does not occur in this catalog. We characterize the properties of the dense molecular gas emission toward the entire sample. HCO{sup +} is very sub-thermally populated and the 3-2 transitions are optically thick toward most BGPS clumps. The median observed line width is 3.3 km s{sup –1} consistent with supersonic turbulence within BGPS clumps. We find strong correlations between dense molecular gas integrated intensities and 1.1 mm peak flux and the gas kinetic temperature derived from previously published NH{sub 3} observations. These intensity correlations are driven by the sensitivity of the 3-2 transitions to excitation conditions rather than by variations in molecular column density or abundance. We identify a subset of 113 sources with stronger N{sub 2}H{sup +} than HCO{sup +} integrated intensity, but we find no correlations between the N{sub 2}H{sup +}/HCO{sup +} ratio and 1.1 mm continuum flux density, gas kinetic temperature, or line width. Self-absorbed profiles are rare (1.3%)

  8. A slice of the universe

    NASA Technical Reports Server (NTRS)

    De Lapparent, V.; Geller, M. J.; Huchra, J. P.

    1986-01-01

    A preliminary discussion is presented of recent results obtained as part of the extension of the Center of Astrophysics redshift survey. Several features of the results are striking. The distribution of galaxies in the sample, which contains 1100 galaxies in a 6 deg x 117 deg strip going through the Coma cluster, looks like a slice through the suds in the kitchen sink. It appears that the galaxies are on the surfaces of bubble-like structures with diameters of 25-50/h-Mpc. The largest bubble in the survey has a diameter comparable with the most recent estimates of the diameter of the void in Bootes. This topology poses serious challenges for current models for the formation of large-scale structure. The best available model for generating these structures is the explosive galaxy formation theory of Ostriker and Cowie (1981).

  9. Electrohydrodynamic drying of carrot slices.

    PubMed

    Ding, Changjiang; Lu, Jun; Song, Zhiqing

    2015-01-01

    Carrots have one of the highest levels of carotene, and they are rich in vitamins, fiber and minerals. However, since fresh carrots wilt rapidly after harvest under inappropriate storage conditions, drying has been used to improve their shelf life and retain nutritional quality. Therefore, to further investigate the potential of this method, carrot slices were dried in an EHD system in order to study the effect of different voltages on drying rate. As measures of quality, carotene content and rehydration ratio were, respectively, compared against the conventional oven drying regime. Carotene, the main component of the dried carrot, and rehydration characteristics of the dried product can both indicate quality by physical and chemical changes during the drying process. Mathematical modeling and simulation of drying curves were also performed, using root mean square error, reduced mean square of the deviation and modeling efficiency as the primary criteria to select the equation that best accounts for the variation in the drying curves of the dried samples. Theoretically, the Page model was best suited for describing the drying rate curve of carrot slices at 10kV to 30kV. Experimentally, the drying rate of carrots was notably greater in the EHD system when compared to control, and quality, as determined by carotene content and rehydration ratio, was also improved when compared to oven drying. Therefore, this work presents a facile and effective strategy for experimentally and theoretically determining the drying properties of carrots, and, as a result, it provides deeper insight into the industrial potential of the EHD drying technique. PMID:25874695

  10. Electrohydrodynamic Drying of Carrot Slices

    PubMed Central

    Ding, Changjiang; Lu, Jun; Song, Zhiqing

    2015-01-01

    Carrots have one of the highest levels of carotene, and they are rich in vitamins, fiber and minerals. However, since fresh carrots wilt rapidly after harvest under inappropriate storage conditions, drying has been used to improve their shelf life and retain nutritional quality. Therefore, to further investigate the potential of this method, carrot slices were dried in an EHD system in order to study the effect of different voltages on drying rate. As measures of quality, carotene content and rehydration ratio were, respectively, compared against the conventional oven drying regime. Carotene, the main component of the dried carrot, and rehydration characteristics of the dried product can both indicate quality by physical and chemical changes during the drying process. Mathematical modeling and simulation of drying curves were also performed, using root mean square error, reduced mean square of the deviation and modeling efficiency as the primary criteria to select the equation that best accounts for the variation in the drying curves of the dried samples. Theoretically, the Page model was best suited for describing the drying rate curve of carrot slices at 10kV to 30kV. Experimentally, the drying rate of carrots was notably greater in the EHD system when compared to control, and quality, as determined by carotene content and rehydration ratio, was also improved when compared to oven drying. Therefore, this work presents a facile and effective strategy for experimentally and theoretically determining the drying properties of carrots, and, as a result, it provides deeper insight into the industrial potential of the EHD drying technique. PMID:25874695

  11. MODELLING TRANSFER OF LISTERIA MONOCYTOGENES DURING SLICING OF "GRAVAD" SALMON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transfer of a rifampicin-resistant mutant of Listeria monocytogenes strain F2365 from an inoculated slicing blade to slices of gravad salmon (Salmo salar), and from inoculated salmon fillet to the slicing machine and subsequently to slices of uninoculated fillet was studied. The effect of slicing te...

  12. Integrating interface slicing into software engineering processes

    NASA Technical Reports Server (NTRS)

    Beck, Jon

    1993-01-01

    Interface slicing is a tool which was developed to facilitate software engineering. As previously presented, it was described in terms of its techniques and mechanisms. The integration of interface slicing into specific software engineering activities is considered by discussing a number of potential applications of interface slicing. The applications discussed specifically address the problems, issues, or concerns raised in a previous project. Because a complete interface slicer is still under development, these applications must be phrased in future tenses. Nonetheless, the interface slicing techniques which were presented can be implemented using current compiler and static analysis technology. Whether implemented as a standalone tool or as a module in an integrated development or reverse engineering environment, they require analysis no more complex than that required for current system development environments. By contrast, conventional slicing is a methodology which, while showing much promise and intuitive appeal, has yet to be fully implemented in a production language environment despite 12 years of development.

  13. Energetic and exergetic performance analysis and modeling of drying kinetics of kiwi slices.

    PubMed

    Darvishi, Hosain; Zarein, Mohammad; Farhudi, Zanyar

    2016-05-01

    This work focused on the effects of the moisture content, slices thickness and microwave power on aspects of energy and exergy, drying kinetics, moisture diffusivity, activation energy, and modeling of the thin layer drying of kiwi slices. Results showed that energy and exergy efficiency increased with increasing microwave power and decreasing slice thickness while values of energy efficiency (15.15-32.27 %) were higher than exergy efficiency (11.35-24.68 %). Also, these parameters decreased with a decrease in moisture content. Specific energy consumption varied from 7.79 to 10.02, 8.59 to 10.77 and 9.57 to16.20 to MJ/kg water evaporated for 3, 6 and 9 mm, respectively. The values of exergy loss were found to be in the range of 5.90 and 14.39 MJ/kg water and decreased as the microwave power increased and slice thickness decreased. Effective diffusivity increased with decreasing moisture content and increasing microwave power and slice thickness. Average effective moisture diffusivity of kiwi slices changes between 1.47 × 10(-9) and 39.29 × 10(-9) m(2)/s within the given variables range. Activation energy (17.96-21.38 W/g) showed a significant dependence on the moisture content. Although the Midilli model showed the best fit, Page's model was selected, since it had almost a similar performance but the model is simpler with two parameters instead of four. PMID:27407198

  14. Visible human slice sequence animation Web server

    NASA Astrophysics Data System (ADS)

    Bessaud, Jean-Christophe; Hersch, Roger D.

    2000-12-01

    Since June 1998, EPFL's Visible Human Slice Server (http://visiblehuman.epfl.ch) allows to extract arbitrarily oriented and positioned slices. More than 300,000 slices are extracted each year. In order to give a 3D view of anatomic structures, a new service has been added for extracting slice animations along a user-defined trajectory. This service is useful both for research and teaching purposes (http:visiblehuman.epfl.ch/animation/). Extracting slices of animations at any desired position and orientation from the Visible Human volume (Visible Man or Woman) requires both high throughput and much processing power. The I/O disk bandwidth can be increased by accessing more than one disk at the same time, i.e. by stripping data across several disks and by carrying out parallel asynchronous disk accesses. Since processing operations such as slice and animation extraction are compute- intensive, they require the program execution to be carried out in parallel on several computers. In the present contribution, we describe the new slice sequence animation service as well as the approach taken for parallelizing this service on a multi-PC multi-disk Web server.

  15. Deep 1.1mm-wavelength imaging of the GOODS-S field by AzTEC/ASTE - I. Source catalogue and number counts

    NASA Astrophysics Data System (ADS)

    Scott, K. S.; Yun, M. S.; Wilson, G. W.; Austermann, J. E.; Aguilar, E.; Aretxaga, I.; Ezawa, H.; Ferrusca, D.; Hatsukade, B.; Hughes, D. H.; Iono, D.; Giavalisco, M.; Kawabe, R.; Kohno, K.; Mauskopf, P. D.; Oshima, T.; Perera, T. A.; Rand, J.; Tamura, Y.; Tosaki, T.; Velazquez, M.; Williams, C. C.; Zeballos, M.

    2010-07-01

    We present the first results from a confusion-limited map of the Great Observatories Origins Deep Survey-South (GOODS-S) taken with the AzTEC camera on the Atacama Submillimeter Telescope Experiment. We imaged a field to a 1σ depth of 0.48-0.73 mJybeam-1, making this one of the deepest blank-field surveys at mm-wavelengths ever achieved. Although by traditional standards our GOODS-S map is extremely confused due to a sea of faint underlying sources, we demonstrate through simulations that our source identification and number counts analyses are robust, and the techniques discussed in this paper are relevant for other deeply confused surveys. We find a total of 41 dusty starburst galaxies with signal-to-noise ratios S/N >= 3. 5 within this uniformly covered region, where only two are expected to be false detections, and an additional seven robust source candidates located in the noisier (1σ ~ 1 mJybeam-1) outer region of the map. We derive the 1.1 mm number counts from this field using two different methods: a fluctuation or ``P(d)'' analysis and a semi-Bayesian technique and find that both methods give consistent results. Our data are well fit by a Schechter function model with . Given the depth of this survey, we put the first tight constraints on the 1.1 mm number counts at S1.1mm = 0.5 mJy, and we find evidence that the faint end of the number counts at from various SCUBA surveys towards lensing clusters are biased high. In contrast to the 870μm survey of this field with the LABOCA camera, we find no apparent underdensity of sources compared to previous surveys at 1.1mm the estimates of the number counts of SMGs at flux densities >1mJy determined here are consistent with those measured from the AzTEC/SHADES survey. Additionally, we find a significant number of SMGs not identified in the LABOCA catalogue. We find that in contrast to observations at λ <= 500μm, MIPS 24μm sources do not resolve the total energy density in the cosmic infrared background at 1.1

  16. Oxygen measurements in brain stem slices exposed to normobaric hyperoxia and hyperbaric oxygen.

    PubMed

    Mulkey, D K; Henderson, R A; Olson, J E; Putnam, R W; Dean, J B

    2001-05-01

    We previously reported (J Appl Physiol 89: 807-822, 2000) that < or =10 min of hyperbaric oxygen (HBO(2); < or = 2,468 Torr) stimulates solitary complex neurons. To better define the hyperoxic stimulus, we measured PO(2) in the solitary complex of 300-microm-thick rat medullary slices, using polarographic carbon fiber microelectrodes, during perfusion with media having PO(2) values ranging from 156 to 2,468 Torr. Under control conditions, slices equilibrated with 95% O(2) at barometric pressure of 1 atmospheres absolute had minimum PO(2) values at their centers (291 +/- 20 Torr) that were approximately 10-fold greater than PO(2) values measured in the intact central nervous system (10-34 Torr). During HBO(2), PO(2) increased at the center of the slice from 616 +/- 16 to 1,517 +/- 15 Torr. Tissue oxygen consumption tended to decrease at medium PO(2) or = 1,675 Torr to levels not different from values measured at PO(2) found in all media in metabolically poisoned slices (2-deoxy-D-glucose and antimycin A). We conclude that control medium used in most brain slice studies is hyperoxic at normobaric pressure. During HBO(2), slice PO(2) increases to levels that appear to reduce metabolism. PMID:11299283

  17. Quantification and elimination of windmill artifacts in multi slice CT

    NASA Astrophysics Data System (ADS)

    Utrup, Steven J.; Brown, Kevin M.

    2008-03-01

    In multi-slice cone beam CT imaging, there are artifacts known as windmill artifacts. These artifacts are due to not satisfying the Nyquist criteria in the patient longitudinal direction. This paper quantifies and compares these artifacts as a function of the number of rows, pitch, collimation, and image thickness of the CT scanner. Scanners with rows of 16, 64 and 128 are measured and compared with simulated data, using both Helical and Axial scanning modes. In addition three focal spot switching modes are compared: the traditional within image plane mode; diagonal mode; and quad mode. All images are compared via four criteria: artifacts, MTF, SSP and noise. Results show that the frequency of the artifact, or number of blades on the windmill and magnitude of each blade, is dependent on the rate at which the rows are crossed for an image. For example, for a given pitch, doubling the rows doubles the frequency of the artifact, with each artifact approximately the magnitude. A similar result can be obtained by keeping the number of rows constant and varying the pitch. The artifact disappears as the Nyquist criteria is satisfied by either increasing the slice thickness or incorporating one of the focal spot switching modes that switch in the patient longitudinal direction. For a given MTF and SSP, the diagonal focal spot switching mode has slightly more noise while the other two are approximately equal. The artifact varies with the quad mode being the best and traditional mode being the worse.

  18. Thick Toenails

    MedlinePlus

    ... be seen in individuals with nail fungus (onychomycosis), psoriasis, and hypothyroidism. Those who have problems with the thickness of their toenails should consult a foot and ankle surgeon for proper diagnosis and treatment. and or or and or or, browse by ...

  19. Extending the viability of acute brain slices.

    PubMed

    Buskila, Yossi; Breen, Paul P; Tapson, Jonathan; van Schaik, André; Barton, Matthew; Morley, John W

    2014-01-01

    The lifespan of an acute brain slice is approximately 6-12 hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36 hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research. PMID:24930889

  20. Coordinate singularities in harmonically sliced cosmologies

    NASA Astrophysics Data System (ADS)

    Hern, Simon D.

    2000-08-01

    Harmonic slicing has in recent years become a standard way of prescribing the lapse function in numerical simulations of general relativity. However, as was first noticed by Alcubierre [Phys. Rev. D 55, 5981 (1997)], numerical solutions generated using this slicing condition can show pathological behavior. In this paper, analytic and numerical methods are used to examine harmonic slicings of Kasner and Gowdy cosmological spacetimes. It is shown that in general the slicings are prevented from covering the whole of the spacetimes by the appearance of coordinate singularities. As well as limiting the maximum running times of numerical simulations, the coordinate singularities can lead to features being produced in numerically evolved solutions which must be distinguished from genuine physical effects.

  1. Photosynthesis and Respiration in Leaf Slices.

    ERIC Educational Resources Information Center

    Brown, Simon

    1998-01-01

    Demonstrates how leaf slices provide an inexpensive material for illustrating several fundamental points about the biochemistry of photosynthesis and respiration. Presents experiments that illustrate the effects of photon flux density and herbicides and carbon dioxide concentration. (DDR)

  2. Radiation phantom with humanoid shape and adjustable thickness (RPHAT).

    PubMed

    Lehmann, Joerg; Stern, Robin L; Levy, Joshua; Daly, Thomas P; Siantar, Christine L Hartmann; Goldberg, Zelanna

    2004-05-01

    A new radiation phantom with humanoid shape and adjustable thickness (RPHAT) has been developed. Unlike the RANDO phantom which is a fixed thickness, this newly designed phantom has adjustable thickness to address the range of thicknesses of real-world patients. RPHAT allows adjustment of the body thickness by being sliced in the coronal (instead of axial) direction. Centre slices are designed so that more sections can be added or removed while maintaining the anthropomorphic shape. A prototype of the new phantom has been successfully used in a study investigating peripheral dose delivery, where the amount of scatter within the patient, and therefore the patient thickness, plays a critical role in dose deposition. This newly designed phantom is an important tool to improve the quality of radiation therapy. PMID:15152935

  3. Radiation Phantom with Humanoid Shape and Adjustable Thickness (RPHAT)

    SciTech Connect

    Lehmann, J; Stern, R L; Levy, J; Daly, T; Hartmann-Siantar, C L; Goldberg, Z

    2003-08-11

    A new radiation phantom with humanoid shape and adjustable thickness (RPHAT) has been developed. Unlike the RANDO{reg_sign} Phantom which is a fixed thickness, this newly designed phantom has adjustable thickness to address the variable thickness of real-world patients. RPHAT allows adjustment of the body thickness by being sliced in the coronal direction (as opposed to axial). Center slices are designed such that more sections can be added or removed while maintaining the anthropomorphic shape. A prototype of the new phantom has been successfully used in a study investigating peripheral dose delivery, where the amount of scatter within the patient, and therefore the patient thickness, plays a critical role in dose deposition. This newly designed phantom is an important tool to improve the quality of radiation therapy.

  4. Effects of broiler breast meat thickness and background on color measurements.

    PubMed

    Bianchi, M; Fletcher, D L

    2002-11-01

    Experiments were conducted to determine the influence of broiler and turkey breast meat thickness and background on breast meat color measurements. Broiler breast fillets were sliced into two 1 cm thick slices and the turkey breast fillets into three 1 cm slices. Color values for lightness (L*), redness (a*), and yellowness (b*) were measured on the same top slice singly or while placed over the corresponding broiler and turkey slices. Color was measured in triplicate while the fillets were placed on the following backgrounds: plastic-coated white paper, white nylon, aluminum foil, black plastic, and a yellow commercial packaging tray (broiler only). Sample thickness significantly affected L*, a*, and b* values of turkey and chicken. Increased breast meat thickness resulted in lower L*, a*, and b5 values. Increased turkey meat thickness from 1 to 2 cm resulted in lower a* and b* values; however, only lower L* values were observed, with sample thickness increased from 1 to 3 cm. No differences in meat color were found when increasing turkey meat sample thickness from 2 to 3 cm. Background had a significant effect on single (1 cm) broiler and turkey meat color measurements but did not influence the color readings of the thicker multiple slice samples. These results indicate that the application of machine vision or in-line color measurement systems may have to take into account breast meat thickness, and in thinner samples, background color. PMID:12455607

  5. Thin layer drying of tomato slices.

    PubMed

    Das Purkayastha, Manashi; Nath, Amit; Deka, Bidyut Chandra; Mahanta, Charu Lata

    2013-08-01

    The hot air convective drying characteristics of blanched tomato (Lycopersicon esculantum L.) slices have been investigated. Drying experiments were carried out at four different temperatures (50, 60, 65 and 70 °C). The effect of drying temperatures on the drying behavior of the tomato slices was evaluated. All drying experiments had only falling rate period. The average effective diffusivity values varied from 0.5453 × 10(-9) to 2.3871 × 10(-9) m(2)/s over the temperature range studied and the activation energy was estimated to be 61.004 kJ/mol. In order to select a suitable form of the drying curve, six different thin layer drying models (Henderson-Pabis, Page, Diamante et al., Wang and Singh, Logarithmic and Newton models) were fitted to the experimental data. The goodness of fit tests indicated that the Logarithmic model gave the best fit to experimental results, which was closely followed by the Henderson-Pabis model. The influence of varied drying temperatures on quality attributes of the tomato slices viz. Hunter color parameters, ascorbic acid, lycopene, titratable acidity, total sugars, reducing sugars and sugar/acid ratio of dried slices was also studied. Slices dried at 50 and 60 °C had high amount of total sugars, lycopene, sugar/acid ratio, Hunter L- and a-values. Drying of slices at 50 °C revealed optimum retention of ascorbic acid, sugar/acid ratio and red hue, whereas, drying at higher temperature (65 and 70 °C) resulted in a considerable decrease in nutrients and colour quality of the slices. PMID:24425966

  6. Visual patch clamp recording of neurons in thick portions of the adult spinal cord.

    PubMed

    Munch, Anders Sonne; Smith, Morten; Moldovan, Mihai; Perrier, Jean-François

    2010-07-15

    The study of visually identified neurons in slice preparations from the central nervous system offers considerable advantages over in vivo preparations including high mechanical stability in the absence of anaesthesia and full control of the extracellular medium. However, because of their relative thinness, slices are not appropriate for investigating how individual neurons integrate synaptic inputs generated by large numbers of neurons. Here we took advantage of the exceptional resistance of the turtle to anoxia to make slices of increasing thicknesses (from 300 to 3000 microm) from the lumbar enlargement of the spinal cord. With a conventional upright microscope in which the light condenser was carefully adjusted, we could visualize neurons present at the surface of the slice and record them with the whole-cell patch clamp technique. We show that neurons present in the middle of the preparation remain alive and capable of generating action potentials. By stimulating the lateral funiculus we can evoke intense synaptic activity associated with large increases in conductance of the recorded neurons. The conductance increases substantially more in neurons recorded in thick slices suggesting that the size of the network recruited with the stimulation increases with the thickness of the slices. We also find that that the number of spontaneous excitatory postsynaptic currents (EPSCs) is higher in thick slices compared with thin slices while the number of spontaneous inhibitory postsynaptic currents (IPSCs) remains constant. These preliminary data suggest that inhibitory and excitatory synaptic connections are balanced locally while excitation dominates long-range connections in the spinal cord. PMID:20488203

  7. A Myocardial Slice Culture Model Reveals Alpha-1A-Adrenergic Receptor Signaling in the Human Heart

    PubMed Central

    Thomas, R. Croft; Singh, Abhishek; Cowley, Patrick; Myagmar, Bat-Erdene; Montgomery, Megan D.; Swigart, Philip M.; De Marco, Teresa; Baker, Anthony J.; Simpson, Paul C.

    2016-01-01

    Background Translation of preclinical findings could benefit from a simple, reproducible, high throughput human model to study myocardial signaling. Alpha-1A-adrenergic receptors (ARs) are expressed at very low levels in the human heart, and it is unknown if they function. Objectives To develop a high throughput human myocardial slice culture model, and to test the hypothesis that alpha-1A- ARs are functional in the human heart. Methods Cores of LV free wall 8 mm diameter were taken from 52 hearts (18 failing and 34 nonfailing). Slices 250 μm thick were cut with a Krumdieck apparatus and cultured using a rotating incubation unit. Results About 60 slices were cut from each LV core, and a typical study could use 96 slices. Myocyte morphology was maintained, and diffusion into the slice center was rapid. Slice viability was stable for at least 3 days in culture by ATP and MTT assays. The beta-AR agonist isoproterenol stimulated phospholamban phosphorylation, and the alpha-1A-AR agonist A61603 stimulated ERK phosphorylation, with nanomolar EC50 values in slices from both failing and nonfailing hearts. Strips cut from the slices were used to quantify activation of contraction by isoproterenol, A61603, and phenylephrine. The slices supported transduction by adenovirus. Conclusions We have developed a simple, high throughput LV myocardial slice culture model to study signaling in the human heart. This model can be useful for translational studies, and we show for the first time that the alpha-1A-AR is functional in signaling and contraction in the human heart. PMID:27453955

  8. Ultrafast multi-slice spatiotemporally encoded MRI with slice-selective dimension segmented.

    PubMed

    Zhang, Ting; Chen, Lin; Huang, Jianpan; Li, Jing; Cai, Shuhui; Cai, Congbo; Chen, Zhong

    2016-08-01

    As a recently emerging method, spatiotemporally encoded (SPEN) magnetic resonance imaging (MRI) has a high robustness to field inhomogeneity and chemical shift effect. It has been broadened from single-slice scanning to multi-slice scanning. In this paper, a novel multi-slice SPEN MRI method was proposed. In this method, the slice-selective dimension was segmented to lower the specific absorption rate (SAR) and improve the image quality. This segmented method, dubbed SeSPEN method, was theoretically analyzed and demonstrated with phantom, lemon and in vivo rat brain experiments. The experimental results were compared with the results obtained from the spin-echo EPI, spin-echo SPEN method and multi-slice global SPEN method proposed by Frydman and coauthors (abbr. GlSPEN method). All the SPEN images were super-resolved reconstructed using deconvolution method. The results indicate that the SeSPEN method retains the advantage of SPEN MRI with respect to resistance to field inhomogeneity and can provide better signal-to-noise ratio than multi-slice GlSPEN MRI technique. The SeSPEN method has comparable SAR to the GlSPEN method while the T1 signal attenuation effect is alleviated. The proposed method will facilitate the multi-slice SPEN MRI to scan more slices within one scan with better image quality. PMID:27301072

  9. Ultrafast multi-slice spatiotemporally encoded MRI with slice-selective dimension segmented

    NASA Astrophysics Data System (ADS)

    Zhang, Ting; Chen, Lin; Huang, Jianpan; Li, Jing; Cai, Shuhui; Cai, Congbo; Chen, Zhong

    2016-08-01

    As a recently emerging method, spatiotemporally encoded (SPEN) magnetic resonance imaging (MRI) has a high robustness to field inhomogeneity and chemical shift effect. It has been broadened from single-slice scanning to multi-slice scanning. In this paper, a novel multi-slice SPEN MRI method was proposed. In this method, the slice-selective dimension was segmented to lower the specific absorption rate (SAR) and improve the image quality. This segmented method, dubbed SeSPEN method, was theoretically analyzed and demonstrated with phantom, lemon and in vivo rat brain experiments. The experimental results were compared with the results obtained from the spin-echo EPI, spin-echo SPEN method and multi-slice global SPEN method proposed by Frydman and coauthors (abbr. GlSPEN method). All the SPEN images were super-resolved reconstructed using deconvolution method. The results indicate that the SeSPEN method retains the advantage of SPEN MRI with respect to resistance to field inhomogeneity and can provide better signal-to-noise ratio than multi-slice GlSPEN MRI technique. The SeSPEN method has comparable SAR to the GlSPEN method while the T1 signal attenuation effect is alleviated. The proposed method will facilitate the multi-slice SPEN MRI to scan more slices within one scan with better image quality.

  10. A quasi-continuous record of atmospheric opacity at lambda = 1.1 mm over 34 days at Mauna Kea Observatory

    NASA Technical Reports Server (NTRS)

    De Zafra, R. L.; Parrish, A.; Solomon, P. M.; Barrett, J. W.

    1983-01-01

    A quasi-continuous record of atmospheric attenuation is obtained. The data were gathered during a 24-day period in September and October 1982 and a 10-day period in December of that year. The opacity is arrived at by measuring the thermal emission of the atmosphere over a bandwidth of approximately 300 MHz. Using an experimental relationship established by Zammit and Ade (1981), opacity measurements at 1.1 mm are converted to the precipitable water vapor column overhead. With the precipitable water vapor, estimates of opacity due to water vapor can be made for other mm and FIR wavelengths. These estimates require model absorption curves for the atmosphere.

  11. Performance evaluation of a 64-slice CT system with z-flying focal spot.

    PubMed

    Flohr, T; Stierstorfer, K; Raupach, R; Ulzheimer, S; Bruder, H

    2004-12-01

    The meanwhile established generation of 16-slice CT systems enables routine sub-millimeter imaging at short breath-hold times. Clinical progress in the development of multidetector row CT (MDCT) technology beyond 16 slices can more likely be expected from further improvement in spatial and temporal resolution rather than from a mere increase in the speed of volume coverage. We present an evaluation of a recently introduced 64-slice CT system (SOMATOM Sensation 64, Siemens AG, Forchheim, Germany), which uses a periodic motion of the focal spot in longitudinal direction (z-flying focal spot) to double the number of simultaneously acquired slices. This technique acquires 64 overlapping 0.6 mm slices per rotation. The sampling scheme corresponds to that of a 64 x 0.3 mm detector, with the goal of improved longitudinal resolution and reduced spiral artifacts. After an introduction to the detector design, we discuss the basics of z-flying focal spot technology (z-Sharp). We present phantom and specimen scans for performance evaluation. The measured full width at half maximum (FWHM) of the thinnest spiral slice is 0.65 mm. All spiral slice widths are almost independent of the pitch, with deviations of less than 0.1 mm from the nominal value. Using a high-resolution bar pattern phantom (CATPHAN, Phantom Laboratories, Salem, NY), the longitudinal resolution can be demonstrated to be up to 15 lp/cm at the isocenter independent of the pitch, corresponding to a bar diameter of 0.33 mm. Longitudinal resolution is only slightly degraded for off-center locations. At a distance of 100 mm from the isocenter, 14 lp/cm can be resolved in the z-direction, corresponding to a bar diameter of 0.36 mm. Spiral "windmill" artifacts presenting as hyper- and hypodense structures around osseous edges are effectively reduced by the z-flying focal spot technique. Cardiac scanning benefits from the short gantry rotation time of 0.33 s, providing up to 83 ms temporal resolution with 2-segment ECG

  12. Glycine metabolism in rat kidney cortex slices.

    PubMed

    Rowsell, E V; Al-Naama, M M; Rowsell, K V

    1982-04-15

    When rat kidney cortex slices were incubated with glycine or [1-14C]glycine, after correcting for metabolite changes with control slices, product formation and glycine utilization fitted the requirements of the equation: 2 Glycine leads to ammonia + CO2 + serine. Evidence is presented that degradation via glyoxylate, by oxidation or transamination, is unlikely to have any significant role in kidney glycine catabolism. It is concluded that glycine metabolism in rat kidney is largely via glycine cleavage closely coupled with serine formation. 1-C decarboxylation and urea formation with glycine in rat hepatocyte suspensions were somewhat greater than decarboxylation or ammonia formation in kidney slices, showing that in the rat, potentially, the liver is quantitatively the more important organ in glycine catabolism. There was no evidence of ammonia formation from glycine with rat brain cortex, heart, spleen or diaphragm and 1-C decarboxylation was very weak. PMID:6810880

  13. Golgi apparatus cisternae of monensin-treated cells accumulate in the cytoplasm of liver slices.

    PubMed

    Morré, D J; Morré, D M; Mollenhauer, H H; Reutter, W

    1987-04-01

    Protein transport via the endoplasmic reticulum Golgi apparatus-cell surface export route was blocked when slices (6-15 cells thick) of livers of 10-day-old rats were incubated with 1 microM monensin. Production of secretory vesicles by Golgi apparatus was reduced or eliminated and, in their place, swollen cisternae accumulated in the cytoplasm at the trans Golgi apparatus face. The swelling response was restricted to the six external cell layers of the liver slices, and the number of cells showing the response was little increased by either a greater concentration of monensin or by longer times of incubation. When monensin was added post-chase to the slices, flux of radioactive proteins to the cell surface was inhibited by about 80% as determined from standard pulse-chase analyses with isolated cell fractions. Radioactive proteins accumulated in both endoplasmic reticulum and Golgi apparatus and in a fraction that may contain monensin-blocked Golgi apparatus cisternae released from the stack. The latter fraction was characterized by galactosyltransferase/thiamine pyrophosphatase ratios similar to those of Golgi apparatus from control slices. The use of monensin with the tissue slice system may provide an opportunity for the cells to accumulate monensin-blocked Golgi apparatus cisternae in sufficient quantities to permit their isolation and purification by conventional cell fractionation methods. PMID:3595634

  14. Anti-hepatitis C virus potency of a new autophagy inhibitor using human liver slices model

    PubMed Central

    Lagaye, Sylvie; Brun, Sonia; Gaston, Jesintha; Shen, Hong; Stranska, Ruzena; Camus, Claire; Dubray, Clarisse; Rousseau, Géraldine; Massault, Pierre-Philippe; Courcambeck, Jerôme; Bassisi, Firas; Halfon, Philippe; Pol, Stanislas

    2016-01-01

    AIM: To evaluate the antiviral potency of a new anti-hepatitis C virus (HCV) antiviral agent targeting the cellular autophagy machinery. METHODS: Non-infected liver slices, obtained from human liver resection and cut in 350 μm-thick slices (2.7 × 106 cells per slice) were infected with cell culture-grown HCV Con1b/C3 supernatant (multiplicity of infection = 0.1) cultivated for up to ten days. HCV infected slices were treated at day 4 post-infection with GNS-396 for 6 d at different concentrations. HCV replication was evaluated by strand-specific real-time quantitative reverse transcription - polymerase chain reaction. The infectivity titers of supernatants were evaluated by foci formation upon inoculation into naive Huh-7.5.1 cells. The cytotoxic effect of the drugs was evaluated by lactate dehydrogenase leakage assays. RESULTS: The antiviral efficacy of a new antiviral drug, GNS-396, an autophagy inhibitor, on HCV infection of adult human liver slices was evidenced in a dose-dependent manner. At day 6 post-treatment, GNS-396 EC50 was 158 nmol/L without cytotoxic effect (compared to hydroxychloroquine EC50 = 1.17 μmol/L). CONCLUSION: Our results demonstrated that our ex vivo model is efficient for evaluation the potency of autophagy inhibitors, in particular a new quinoline derivative GNS-396 as antiviral could inhibit HCV infection in a dose-dependent manner without cytotoxic effect. PMID:27478540

  15. ID slicing and the automated factory

    NASA Technical Reports Server (NTRS)

    Lewandowski, T.

    1982-01-01

    The automation of the slicing system utilizing internal-diameter saws for the production of the silicon wafers used in solar arrays is discussed. It is argued that saw productivity can be increased by reducing silicon waste, decreasing usage of consumables, keeping the saw slicing, and increasing the cutting speed. Several machine enhancements utilizing automatic control are discussed. The need for record keeping to anticipate maintenance operations is noted, and a digital serial communication interface with the microprocessor-based saws is recommended. Distributed control of the manufacturing process is discussed in detail, and is recommended as a method for increasing productivity.

  16. Silicon ingot casting: Heat exchanger method. Multi-wire slicing: Fixed abrasive slicing technique, phase 3

    NASA Technical Reports Server (NTRS)

    Schmid, F.; Khattak, C. P.

    1979-01-01

    In the area of ingot casting the proof of concept of heat exchanger method (HEM) was established. It was also established that HEM cast silicon yielded solar cell performance comparable to Czochralski grown material. Solar cells with conversion efficiencies of up to 15% were fabricated. It was shown that square cross-section ingots can be cast. In the area of crystal slicing, it was established that silicon can be sliced efficiently with the fixed abrasive slicing technique approach. This concept was carried forward to 10 cm diameter workpiece.

  17. Holographic recording in acrylamide photopolymers: thickness limitations.

    PubMed

    Mahmud, Mohammad Sultan; Naydenova, Izabela; Pandey, Nitesh; Babeva, Tzwetanka; Jallapuram, Raghavendra; Martin, Suzanne; Toal, Vincent

    2009-05-10

    Holographic recording in thick photopolymer layers is important for application in holographic data storage, volume holographic filters, and correlators. Here, we studied the characteristics of acrylamide-based photopolymer layers ranging in thickness from 250 microm to 1 mm. For each thickness, samples with three different values of absorbance were studied. By measuring the diffraction efficiency growth of holographically recorded gratings and studying the diffraction patterns obtained, the influence of scattering on the diffraction efficiency of thick volume holographic gratings was analyzed. It was found that, above a particular thickness and absorbance, the diffraction efficiency significantly decreased because of increased holographic scattering. From the diffraction efficiency dependence on absorbance and thickness it is possible to choose photopolymer layer properties that are suitable for a particular holographic application. This study was carried out to determine the highest layer thickness that could be used for phase code multiplexed holographic data storage utilizing thick photopolymer layers as a recording medium. Based on our studies to date we believe that the layer to be used for phase coded reference beam recording with 0.1 absorbance at 532 nm can have a thickness up to 450 microm. The potential use of thicker layers characterized by low scattering losses is part of our continuing research. PMID:19424384

  18. nem_slice ver. 3.34

    2009-06-08

    Nem_slice reads in a finite element model description of the geometry of a problem from an ExodusII file and generates either a nodal or elemental graph of the problem. It then calls Chaco to load balance the graph and then outputs a NemesisI load-balance file.

  19. Detecting Psychopathy from Thin Slices of Behavior

    ERIC Educational Resources Information Center

    Fowler, Katherine A.; Lilienfeld, Scott O.; Patrick, Christopher J.

    2009-01-01

    This study is the first to demonstrate that features of psychopathy can be reliably and validly detected by lay raters from "thin slices" (i.e., small samples) of behavior. Brief excerpts (5 s, 10 s, and 20 s) from interviews with 96 maximum-security inmates were presented in video or audio form or in both modalities combined. Forty raters used…

  20. Thin-Slice Perception Develops Slowly

    ERIC Educational Resources Information Center

    Balas, Benjamin; Kanwisher, Nancy; Saxe, Rebecca

    2012-01-01

    Body language and facial gesture provide sufficient visual information to support high-level social inferences from "thin slices" of behavior. Given short movies of nonverbal behavior, adults make reliable judgments in a large number of tasks. Here we find that the high precision of adults' nonverbal social perception depends on the slow…

  1. The Characteristics of LTP Induced in Hippocampal Slices Are Dependent on Slice-Recovery Conditions

    ERIC Educational Resources Information Center

    Godaux, Emile; Ris, Laurence; Capron, Brigitte; Sindic, Christian

    2006-01-01

    In area CA1 of hippocampal slices which are allowed to recover from slicing "in interface" and where recordings are carried out in interface, a single 1-sec train of 100-Hz stimulation triggers a short-lasting long-term potentiation (S-LTP), which lasts 1-2 h, whereas multiple 1-sec trains induce a long-lasting LTP (L-LTP), which lasts several…

  2. Heat and Mass Transfer Modeling of Apple Slice under Simultaneous Infrared Dry-Blanching and Dehydration Process

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To develop a new simultaneous infrared dry blanching and dehydration process for producing high-quality blanched and partially dehydrated products, apple slices with three different thicknesses, 5, 9, and 13 mm, were heated using infrared for up to 10 min at 4000W/m2 IR intensity. The surface and ce...

  3. Bronchial wall region extraction algorithm using multi-slice CT images

    NASA Astrophysics Data System (ADS)

    Akashi, Kengo; Saita, Shinsuke; Kubo, Mitsuru; Kawata, Yoshiki; Niki, Noboru; Nakano, Yasutaka; Niimi, Akio; Matsumoto, Hisako; Oguma, Tsuyoshi; Takiguchi, Yuichi; Kawata, Naoko; Tanabe, Nobuhiro; Ohmatsu, Hironobu; Eguchi, Kenji; Kaneko, Masahiro; Moriyama, Noriyuki

    2009-02-01

    As multi-slice CT develops, there are great expectations for an automatic and computer-support diagnoses. This research is on bronchial area which is composed of the bronchial wall regions and the air regions in the internal bronchial tube. Since to diagnose this is difficult, support diagnosis using CT images is desired. The thickness of bronchial wall changes as the airway of early lung cancer, bronchial asthma and the bronchial enhancing syndrome and others change into a malignant state. These changes are detected and the thickness of bronchial wall becomes important information. In this research, the extraction accuracy of the algorithm for bronchial wall evaluation is good.

  4. TISSUE SLICES IN THE STUDY OF LUNG METABOLISM AND TOXICOLOGY

    EPA Science Inventory

    Lung tissue slices are model systems for the study of pulmonary metabolism. Because of the speed and simplicity of slice preparation, lung slices have been used in studies of oxygen, amino acid, carbohydrate and lipid utilization and adenine nucleotide metabolism. Dose-response c...

  5. Visible Human Slice Web Server: a first assessment

    NASA Astrophysics Data System (ADS)

    Hersch, Roger D.; Gennart, Benoit A.; Figueiredo, Oscar; Mazzariol, Marc; Tarraga, Joaquin; Vetsch, S.; Messerli, Vincent; Welz, R.; Bidaut, Luc M.

    1999-12-01

    The Visible Human Slice Server started offering its slicing services at the end of June 1998. From that date until the end of May, more than 280,000 slices were extracted from the Visible Man, by layman interested in anatomy, by students and by specialists. The Slice Server is based one Bi-Pentium PC and 16 disks. It is a scaled down version of a powerful parallel server comprising 5 Bi-Pentium Pro PCs and 60 disks. The parallel server program was created thanks to a computer-aided parallelization framework, which takes over the task of creating a multi-threaded pipelined parallel program from a high-level parallel program description. On the full blown architecture, the parallel program enables the extraction and resampling of up to 5 color slices per second. Extracting 5 slice/s requires to access the disks and extract subvolumes of the Visible Human at an aggregate throughput of 105 MB/s. The publicly accessible server enables to extract slices having any orientation. The slice position and orientation can either be specified for each slice separately or as a position and orientation offered by a Java applet and possible future improvements. In the very near future, the Web Slice Server will offer additional services, such as the possibility to extract ruled surfaces and to extract animations incorporating slices perpendicular to a user defined trajectory.

  6. Trafficking of astrocytic vesicles in hippocampal slices

    SciTech Connect

    Potokar, Maja; Kreft, Marko; Celica Biomedical Center, Technology Park 24, 1000 Ljubljana ; Lee, So-Young; Takano, Hajime; Haydon, Philip G.; Zorec, Robert; Celica Biomedical Center, Technology Park 24, 1000 Ljubljana

    2009-12-25

    The increasingly appreciated role of astrocytes in neurophysiology dictates a thorough understanding of the mechanisms underlying the communication between astrocytes and neurons. In particular, the uptake and release of signaling substances into/from astrocytes is considered as crucial. The release of different gliotransmitters involves regulated exocytosis, consisting of the fusion between the vesicle and the plasma membranes. After fusion with the plasma membrane vesicles may be retrieved into the cytoplasm and may continue to recycle. To study the mobility implicated in the retrieval of secretory vesicles, these structures have been previously efficiently and specifically labeled in cultured astrocytes, by exposing live cells to primary and secondary antibodies. Since the vesicle labeling and the vesicle mobility properties may be an artifact of cell culture conditions, we here asked whether the retrieving exocytotic vesicles can be labeled in brain tissue slices and whether their mobility differs to that observed in cell cultures. We labeled astrocytic vesicles and recorded their mobility with two-photon microscopy in hippocampal slices from transgenic mice with fluorescently tagged astrocytes (GFP mice) and in wild-type mice with astrocytes labeled by Fluo4 fluorescence indicator. Glutamatergic vesicles and peptidergic granules were labeled by the anti-vesicular glutamate transporter 1 (vGlut1) and anti-atrial natriuretic peptide (ANP) antibodies, respectively. We report that the vesicle mobility parameters (velocity, maximal displacement and track length) recorded in astrocytes from tissue slices are similar to those reported previously in cultured astrocytes.

  7. High-resolution 1050 nm spectral domain retinal optical coherence tomography at 120 kHz A-scan rate with 6.1 mm imaging depth

    PubMed Central

    An, Lin; Li, Peng; Lan, Gongpu; Malchow, Doug; Wang, Ruikang K.

    2013-01-01

    We report a newly developed high speed 1050nm spectral domain optical coherence tomography (SD-OCT) system for imaging posterior segment of human eye. The system is capable of an axial resolution at ~10 µm in air, an imaging depth of 6.1 mm in air, a system sensitivity fall-off at ~6 dB/3mm and an imaging speed of 120,000 A-scans per second. We experimentally demonstrate the system’s capability to perform phase-resolved imaging of dynamic blood flow within retina, indicating high phase stability of the SDOCT system. Finally, we show an example that uses this newly developed system to image posterior segment of human eye with a large view of view (10 × 9 mm2), providing detailed visualization of microstructural features from anterior retina to posterior choroid. The demonstrated system parameters and imaging performances are comparable to those that a typical 1 µm swept source OCT would deliver for retinal imaging. PMID:23411636

  8. Amplitude modulation drive to rectangular-plate linear ultrasonic motors with vibrators dimensions 8 mm x 2.16 mm X 1 mm.

    PubMed

    Ming, Yang; Hanson, Ben; Levesley, Martin C; Walker, Peter G; Watterson, Kevin G

    2006-12-01

    In this paper, to exploit the contribution from not only the stators but also from other parts of miniature ultrasonic motors, an amplitude modulation drive is proposed to drive a miniature linear ultrasonic motor consisting of two rectangular piezoelectric ceramic plates. Using finite-element software, the first longitudinal and second lateral-bending frequencies of the vibrator are shown to be very close when its dimensions are 8 mm x 2.16 mm x 1 mm. So one single frequency power should be able to drive the motor. However, in practice the motor is found to be hard to move with a single frequency power because of its small vibration amplitudes and big frequency difference between its longitudinal and bending resonance, which is induced by the boundary condition variation. To drive the motor effectively, an amplitude modulation drive is used by superimposing two signals with nearly the same frequencies, around the resonant frequency of the vibrators of the linear motor. When the amplitude modulation frequency is close to the resonant frequency of the vibrator's surroundings, experimental results show that the linear motor can move back and forward with a maximum thrust force (over 0.016 N) and a maximum velocity (over 50 mm/s). PMID:17186925

  9. Effect of treatments and packaging on the quality of dried carrot slices during storage.

    PubMed

    Sra, S K; Sandhu, K S; Ahluwalia, P

    2014-04-01

    The present investigation was undertaken to study the effect of treatments and packaging on the quality of dried carrot slices during storage. Carrot cultivar 'Nantes' was sliced into 4.5 mm thick slices which were blanched in water at 95 °C for 4 min followed by dipping in 6% potassium metabisulphite (KMS) solution for 40 min and 350 ppm potassium sorbate solution for 10 min prior to two stage phase drying i.e. at 90 ± 5 °C for 2 h and further drying at 60 ± 5 °C for 7 h in a cross-flow hot air cabinet dryer. The dried carrot slices were packed in 50 g packages of aluminium foil laminate (AFL) (polyethylene, aluminium foil and polyester) and high density polyethylene (HDPE) pouches having 32.5 μm and 56.0 μm thickness respectively and stored under ambient conditions i.e.18.5-29.1 °C temperature and 44.4-60.4% relative humidity for 6 months. Significant (p ≤ 0.05) increase was observed in the moisture content, water activity, reducing sugars and non-enzymatic browning while total solids, total soluble solids, titratable acidity, ascorbic acid, total sugars, pectin, rehydration ratio, sulphur dioxide, sorbic acid and carotenoids decreased significantly (p ≤ 0.05) during storage. Carrot slices pre-treated with 6% KMS and packed in AFL pouches were found to retain best physico-chemical quality. The curried product and soup prepared from dried slices from the same had highly acceptable sensory quality with initial overall acceptability scores 8.2 and 8.5 for curried slices and soup respectively on 9-point hedonic scale. The overall acceptability scores decreased from 8.2 to 7.9 and 8.5 to 7.7 in curried product and soup respectively after 6 months storage. All the samples were microbially safe during 6 months of storage. PMID:24741157

  10. Improved slicing method for GOSAT cloud detection using TIR spectra

    NASA Astrophysics Data System (ADS)

    Someya, Y.; Imasu, R.; Shiomi, K.; Saitoh, N.; Ota, Y.

    2015-12-01

    Greenhouse gas observing SATellite (GOSAT) is a polar orbiting satellite for greenhouse gas observations and the main sensor, TANSO-FTS, has three near-infrared bands and a thermal infrared (TIR) band which covers a wide spectral region of 5.56 - 14.3 mm with resolution of 0.2 cm-1. The algorithm used in this study was based on a cirrus detection technique called CO2 slicing method, modified as described below. The weighting functions which represent sensitivity profiles were calculated at each channel in the TIR band of GOSAT. The channels were reconstructed as sets of several spectral channels for each height level based on the peak heights of the weighting functions. Subsequently, the channel combinations were optimized based on simulation studies for several temperature profile patterns for each latitude and temperature at 500 hPa. The observed data in 2010 were analyzed using these optimized channels. Global cloud amounts and their seasonal variations were validated using Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data. Results show some differences of cloud amounts and heights between GOSAT and CALIPSO, which might be caused by surface temperature biases, the inverse layer, the difference of sensitivity of sensors, and marine stratocumulus clouds. However, the characteristics of horizontal distributions derived using the slicing method were generally agreed with those obtained from CALIPSO and reported in previous researches. In addition, comparison of cloud top height using collocated data showed good agreement and clouds with optical thickness less than 0.1 are detectable using this method.

  11. Drying kinetics, rehydration and colour characteristics of convective hot-air drying of carrot slices

    NASA Astrophysics Data System (ADS)

    Doymaz, İbrahim

    2016-03-01

    The effects of air drying temperature, slice thickness and pre-treatment application on the drying kinetics of carrot slices during convective drying in the range 50-70 °C were investigated. Results indicated that drying time, rehydration ratio and colour characteristics of carrot slices were more affected by drying air temperature, followed by pre-treatment applications. Five thin-layer drying models were applied to describe the drying kinetics. Midilli et al. model was the best model to characterize the drying kinetics of carrot slices. The moisture effective diffusivity calculated from the second Fick's law of diffusion ranged from 3.46 × 10-10 to 1.02 × 10-9 m2/s. The values of activation energy determined from the slope of the Arrhenius plot, ln(D eff ) versus 1/(T + 273.15), were 35.53, 43.42, and 37.75 kJ/mol for blanch, potas and control samples, respectively.

  12. Ballistic labeling and dynamic imaging of astrocytes in organotypic hippocampal slice cultures.

    PubMed

    Benediktsson, Adrienne M; Schachtele, Scott J; Green, Steven H; Dailey, Michael E

    2005-01-30

    Protoplasmic astrocytes in mammalian CNS tissues in vivo have a highly complex 3D morphology, but in dissociated cell cultures they often assume a flattened, fibroblast-like morphology bearing only a few, simple processes. By fluorescent labeling and confocal reconstruction we show that many astrocytes in organotypic hippocampal slice cultures exhibit a more native complex cytoarchitecture. Although astrocytes at the surface of slice cultures show a reactive form with several thick glial fibrillary acidic protein (GFAP)-positive processes, astrocytes situated in deeper portions of tissue slices retain a highly complex 3D morphology with many fine spine- or veil-like protrusions. Dozens of astrocytes can be labeled in single slice cultures by gene gun-mediated ballistic delivery of gold or tungsten particles carrying cDNAs (Biolistics), lipophilic dyes (DiOlistics), or fluorescent intracellular calcium indicators (Calistics). Expression of a membrane-targeted form of eGFP (Lck-GFP) is superior to soluble eGFP for resolving fine astrocytic processes. Time-lapse confocal imaging of Lck-GFP transfected astrocytes or "calistically" labeled astrocytes show structural remodeling and calcium transients, respectively. This approach provides an in vitro system for investigating the functional architecture, development and dynamic remodeling of astrocytes and their relationships to neurons and glia in live mammalian brain tissues. PMID:15585287

  13. Supplementary comparison COOMET.L-S7: Standards of the unit for length (metre) in the measurement range from 0.1 mm to 100 mm

    NASA Astrophysics Data System (ADS)

    Makarevich, V.

    2012-01-01

    The COOMET Project No 390/BY/07, 'Supplementary comparison of standards of the unit for length (metre) in the measurement range from 0.1 mm to 100 mm', KCDB reference COOMET.L-S7, was organized by the Technical Committee TC 1.5 'Length and Angle' of COOMET. This comparison started in May 2007 and finished in October 2010. It was piloted by the Belarusian State Institute of Metrology BelGIM, Minsk, the Republic of Belarus, with other participants as follows: GUM (Warsaw, Poland), DP 'Ukrmetrteststandart' (Kiev, Ukraine), NSC 'Institute of Metrology' (Kharkov, Ukraine), SMU (Bratislava, Slovakia) and RSE 'KazInMetr' (Astana, Kazakhstan). The transfer standards provided by BelGIM were carried to the place of the comparison by NMI attendant specialists as personal baggage, where they were measured. The pilot laboratory processed the data obtained for the deviations of measured median lengths from the nominal lengths of the transfer standards in order to estimate the measurement result differences between the measuring instruments. The conclusion is that the equivalence of the reference installations for parameter measurements of the participating National Metrology Institutes is sufficient, and constitutes an appropriate basis for mutual recognition of measurement results. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by COOMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  14. Mass transfer characteristics of bisporus mushroom ( Agaricus bisporus) slices during convective hot air drying

    NASA Astrophysics Data System (ADS)

    Ghanbarian, Davoud; Baraani Dastjerdi, Mojtaba; Torki-Harchegani, Mehdi

    2016-05-01

    An accurate understanding of moisture transfer parameters, including moisture diffusivity and moisture transfer coefficient, is essential for efficient mass transfer analysis and to design new dryers or improve existing drying equipments. The main objective of the present study was to carry out an experimental and theoretical investigation of mushroom slices drying and determine the mass transfer characteristics of the samples dried under different conditions. The mushroom slices with two thicknesses of 3 and 5 mm were dried at air temperatures of 40, 50 and 60 °C and air flow rates of 1 and 1.5 m s-1. The Dincer and Dost model was used to determine the moisture transfer parameters and predict the drying curves. It was observed that the entire drying process took place in the falling drying rate period. The obtained lag factor and Biot number indicated that the moisture transfer in the samples was controlled by both internal and external resistance. The effective moisture diffusivity and the moisture transfer coefficient increased with increasing air temperature, air flow rate and samples thickness and varied in the ranges of 6.5175 × 10-10 to 1.6726 × 10-9 m2 s-1 and 2.7715 × 10-7 to 3.5512 × 10-7 m s-1, respectively. The validation of the Dincer and Dost model indicated a good capability of the model to describe the drying curves of the mushroom slices.

  15. Modelling transfer of Listeria monocytogenes during slicing of 'gravad' salmon.

    PubMed

    Aarnisalo, Kaarina; Sheen, Shiowshuh; Raaska, Laura; Tamplin, Mark

    2007-08-15

    Transfer of a rifampicin-resistant mutant of Listeria monocytogenes from an inoculated slicing blade to slices of 'gravad' salmon (Salmo salar), and from inoculated salmon fillet to the slicing machine and subsequently to slices of uninoculated fillet was studied. The effect of slicing temperature (0 degrees C, 10 degrees C and room temperature), inoculum level (approx. 3, 5 and 8 log CFU/blade), and attachment time of inoculum to blade (10 min and 2.5 h) were investigated and predictive models of the transfer were produced. In the tests of transfer from inoculated blade (5.9-9.0 log CFU/blade) initially 2.5-5.3 log CFU/g was present on the slices, slowly decreasing to an overall average decrease of 1.6+/-0.2 log CFU/g during slicing of 39 slices; the lowest reduction being 1.3 log CFU/g at 0 degrees C. In tests of transfer from contaminated salmon (7.6+/-0.1 log CFU/fillet) to uninoculated blade and further to uninoculated salmon, the reduction in number of L. monocytogenes in slices was 1.5 log CFU/g during slicing of 39 slices. For example 5.3+/-0.3 log CFU/g was transferred to second slice when the inoculum level was 8.4+/-0.4 log CFU/blade, but clearly (p<0.05) lower total number of L. monocytogenes were transferred to slices when the inoculum level was lower, the temperature was colder or the attachment time was longer. There was a progressive exponential reduction in the quantity of L. monocytogenes transferred and, based on statistical parameters, an exponential model (y=ae((-x/b))) fit the data from different test conditions and was suitable for predicting an expected number of L. monocytogenes on the salmon slices. Based on the predicted values, the logarithmic reduction in number of L. monocytogenes in slices was highest at room temperature with an inoculum level of 8.4+/-0.4 log CFU/blade (attachment time 10 min); the other test conditions differed significantly from this (p<0.05). Despite statistically significant differences, in all test conditions

  16. MODEL-BASED ITERATIVE RECONSTRUCTION ENABLES THE EVALUATION OF THIN-SLICE COMPUTED TOMOGRAPHY IMAGES WITHOUT DEGRADING IMAGE QUALITY OR INCREASING RADIATION DOSE.

    PubMed

    Aurumskjöld, Marie-Louise; Ydström, Kristina; Tingberg, Anders; Söderberg, Marcus

    2016-06-01

    Computed tomography (CT) is one of the most important modalities in a radiological department. This technique not only produces images that enable radiological reports with high diagnostic confidence, but it may also provide an elevated radiation dose to the patient. The radiation dose can be reduced by using advanced image reconstruction algorithms. This study was performed on a Brilliance iCT, equipped with iDose(4) iterative reconstruction and an iterative model-based reconstruction (IMR) method. The purpose was to investigate the effect of reduced slice thickness combined with an IMR method on image quality compared with standard slice thickness with iDose(4) reconstruction. The results of objective and subjective image quality evaluations showed that a thinner slice combined with IMR can improve the image quality and reduce partial volume artefacts compared with the standard slice thickness with iDose(4) In conclusion, IMR enables reduction of the slice thickness while maintaining or even improving image quality versus iDose(4). PMID:26590394

  17. Multi-slice imAGe generation using intra-slice paraLLel imaging and Inter-slice shifting (MAGGULLI)

    NASA Astrophysics Data System (ADS)

    Kim, Dongchan; Seo, Hyunseok; Oh, Changheun; Han, Yeji; Park, HyunWook

    2016-02-01

    For acceleration of imaging time, multi-band imaging techniques (e.g. CAIPIRINHA) use the sensitivity differences of the multi-channel RF coils in the slice selection direction. To more effectively utilize the RF coil characteristics than the conventional multi-band imaging techniques, we propose a new imaging technique, called multi-slice image generation using intra-slice parallel imaging and inter-slice shifting (MAGGULLI). The proposed technique used an inter-slice shifting gradient in slice selection direction to make multi-slice images shift in the frequency encoding direction. Thus, aliasing caused by sub-sampling in the phase encoding direction is orthogonal to that by multi-band imaging with the inter-slice shifting, both of which are resolved by using the sensitivity information of the RF coil. Phantom and in vivo imaging experiments for the acceleration factors up to 10 demonstrate that the quality of the images reconstructed by MAGGULLI are better than that of CAIPIRINHA for high acceleration factors in the qualitative and quantitative analysis.

  18. Thickness characterisation of oil spills using active microwave sensors

    NASA Astrophysics Data System (ADS)

    True, Michael; Shuchman, Robert A.; Kletzli, D. W., Jr.; Johannessen, Johnny A.; Digranes, Gunar; Berg, Sverre; Dalland, Kjell

    1994-12-01

    Oil thickness is a crucial parameter in the characterization of oil spills for environmental impact. The feasibility of using active microwave sensors to measure thickness was addressed in a series of microwave scatterometer experiments performed by Simrad Marine A/S in a wave tank at the Nansen Environmental Remote Sensing Center. The thickness of the oil layer was maintained at levels similar to the thick part of an oil spill (0.1 - 1 mm). The measurements showed the capability of active microwave sensors to measure oil spill thickness when the oil type is known. In addition to thickness characterization, the experiment studied the effects of oil viscosity, incidence angle, wind speed, wind angle, microwave frequency, and polarization. The backscatter contrast was observed to be greater for lower incidence angles which indicates that the ERS-1 viewing geometry is optimum for the detection and measurement of thick oil slicks. A thickness-dependent backscatter model was developed which included the effects of oil viscosity, composite surface effects, and oil-water reflectivities. The model viscous effects saturated when the oil thickness was greater than the viscous boundary layer thickness. This explained the observed C-VV backscatter contrast saturation for low viscosity diesel oil at thicknesses greater than 0.15 mm. The model predicted contrast saturation at greater thicknesses for the higher viscosity oils. The data showed this trend but the measurements did not extend to thicknesses which tested the model completely.

  19. Two-Photon Excitation STED Microscopy in Two Colors in Acute Brain Slices

    PubMed Central

    Bethge, Philipp; Chéreau, Ronan; Avignone, Elena; Marsicano, Giovanni; Nägerl, U. Valentin

    2013-01-01

    Many cellular structures and organelles are too small to be properly resolved by conventional light microscopy. This is particularly true for dendritic spines and glial processes, which are very small, dynamic, and embedded in dense tissue, making it difficult to image them under realistic experimental conditions. Two-photon microscopy is currently the method of choice for imaging in thick living tissue preparations, both in acute brain slices and in vivo. However, the spatial resolution of a two-photon microscope, which is limited to ∼350 nm by the diffraction of light, is not sufficient for resolving many important details of neural morphology, such as the width of spine necks or thin glial processes. Recently developed superresolution approaches, such as stimulated emission depletion microscopy, have set new standards of optical resolution in imaging living tissue. However, the important goal of superresolution imaging with significant subdiffraction resolution has not yet been accomplished in acute brain slices. To overcome this limitation, we have developed a new microscope based on two-photon excitation and pulsed stimulated emission depletion microscopy, which provides unprecedented spatial resolution and excellent experimental access in acute brain slices using a long-working distance objective. The new microscope improves on the spatial resolution of a regular two-photon microscope by a factor of four to six, and it is compatible with time-lapse and simultaneous two-color superresolution imaging in living cells. We demonstrate the potential of this nanoscopy approach for brain slice physiology by imaging the morphology of dendritic spines and microglial cells well below the surface of acute brain slices. PMID:23442956

  20. Vibrodissociation of Neurons from Rodent Brain Slices to Study Synaptic Transmission and Image Presynaptic Terminals

    PubMed Central

    Jun, Sang Beom; Cuzon Carlson, Verginia; Ikeda, Stephen; Lovinger, David

    2011-01-01

    Mechanical dissociation of neurons from the central nervous system has the advantage that presynaptic boutons remain attached to the isolated neuron of interest. This allows for examination of synaptic transmission under conditions where the extracellular and postsynaptic intracellular environments can be well controlled. A vibration-based technique without the use of proteases, known as vibrodissociation, is the most popular technique for mechanical isolation. A micropipette, with the tip fire-polished to the shape of a small ball, is placed into a brain slice made from a P1-P21 rodent. The micropipette is vibrated parallel to the slice surface and lowered through the slice thickness resulting in the liberation of isolated neurons. The isolated neurons are ready for study within a few minutes of vibrodissociation. This technique has advantages over the use of primary neuronal cultures, brain slices and enzymatically isolated neurons including: rapid production of viable, relatively mature neurons suitable for electrophysiological and imaging studies; superior control of the extracellular environment free from the influence of neighboring cells; suitability for well-controlled pharmacological experiments using rapid drug application and total cell superfusion; and improved space-clamp in whole-cell recordings relative to neurons in slice or cell culture preparations. This preparation can be used to examine synaptic physiology, pharmacology, modulation and plasticity. Real-time imaging of both pre- and postsynaptic elements in the living cells and boutons is also possible using vibrodissociated neurons. Characterization of the molecular constituents of pre- and postsynaptic elements can also be achieved with immunological and imaging-based approaches. PMID:21654624

  1. ORGANOTYPIC BRAIN SLICE CULTURES: A REVIEW

    PubMed Central

    HUMPEL, C.

    2015-01-01

    In vitro cell cultures are an important tool for obtaining insights into cellular processes in an isolated system and a supplement to in vivo animal experiments. While primary dissociated cultures permit a single homogeneous cell population to be studied, there is a clear need to explore the function of brain cells in a three-dimensional system where the main architecture of the cells is preserved. Thus, organotypic brain slice cultures have proven to be very useful in investigating cellular and molecular processes of the brain in vitro. This review summarizes (1) the historical development of organotypic brain slices focusing on the membrane technology, (2) methodological aspects regarding culturing procedures, age of donors or media, (3) whether the cholinergic neurons serve as a model of neurodegeneration in Alzheimer’s disease, (4) or the nigrostriatal dopaminergic neurons as a model of Parkinson’s disease and (5) how the vascular network can be studied, especially with regard to a synthetic blood–brain barrier. This review will also highlight some limits of the model and give an outlook on future applications. PMID:26254240

  2. Copper sensitivity in dorsal hippocampus slices.

    PubMed

    Leiva, J; Palestini, M; Tetas, M; López, J

    2000-04-01

    The action of copper on the pyramidal neurons in CA1 of the hippocampus is little understood. Our main aim was to study the possible interaction of copper on the synaptic network in CA1 pyramidal neurons. We used Wistar rats hippocampus slices in a recording chamber. The population response ("population of spikes") collected by an extracellular micropipette under baseline conditions served as control. Copper, GABA, bicuculline and picrotoxin were delivered in different experimental conditions to the slice. One, 10 and 100 microM of copper concentration decreased significantly the amplitude and duration of the population spikes in relation to the control response. This effect did not show concentration dependency. Copper in bicuculline medium decreased significantly the duration response in relation to the control response and in relation to copper effect in a free bicuculline medium. This phenomenon emphasizes the copper action on the GABA (B) and (C) receptors. Copper in a picrotoxin medium increased significantly the excitability of the response. This new effect suggests that copper acts on non-GABA receptors, an effect that could be detected when the GABA receptors were inactivated. As a result of these findings it appears that, under our experimental conditions, copper generated transient sensitivity changes in pyramidal neurons of CA1 dorsal hippocampus. PMID:10782257

  3. AMBER: a PIC slice code for DARHT

    NASA Astrophysics Data System (ADS)

    Vay, Jean-Luc; Fawley, William

    1999-11-01

    The accelerator for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility will produce a 4-kA, 20-MeV, 2-μ s output electron beam with a design goal of less than 1000 π mm-mrad normalized transverse emittance and less than 0.5-mm beam centroid motion. In order to study the beam dynamics throughout the accelerator, we have developed a slice Particle-In-Cell code named AMBER, in which the beam is modeled as a time-steady flow, subject to self, as well as external, electrostatic and magnetostatic fields. The code follows the evolution of a slice of the beam as it propagates through the DARHT accelerator lattice, modeled as an assembly of pipes, solenoids and gaps. In particular, we have paid careful attention to non-paraxial phenomena that can contribute to nonlinear forces and possible emittance growth. We will present the model and the numerical techniques implemented, as well as some test cases and some preliminary results obtained when studying emittance growth during the beam propagation.

  4. Metabolism of Red Beet Slices I. Effects of Washing 1

    PubMed Central

    Reed, D. J.; Kolattukudy, P. E.

    1966-01-01

    The changes in relative participation of pathways of glucose catabolism in red beet slices during washing have been examined using specifically 14C labeled glucoses. Washing of these slices brings about an increase in participation of the pentose phosphate pathway. The composition of the washing medium influences slightly the extent of change in pathway participation. The activity level of certain enzymes participating in the initial stages of glucose catabolism has been measured in fresh and washed beet slices. Fresh slices which barely metabolized gluconate were found to have very little 6-phosphogluconate dehydrogenase activity. Washing brings about a dramatic increase in 6-phosphogluconate dehydrogenase activity and this increase was accompanied by a marked increase in the ability of the slices to metabolize gluconate. In red beet slices the TPNH generated via pentose phosphate pathway appears to be utilized for biosynthetic reductions rather than as respiratory substrate. PMID:16656302

  5. The identification of a Pliocene time slice(s) for data/model comparison

    NASA Astrophysics Data System (ADS)

    Haywood, A. M.; Dolan, A. M.; Pickering, S.; Dowsett, H. J.; McClymont, E. L.; Prescott, C.; Salzmann, U.; Hill, D. J.; Hunter, S. J.; Lunt, D. J.; Pope, J. O.; Valdes, P. J.

    2012-12-01

    The characteristics of the mid-Pliocene Warm Period (3.264 to 3.025 Ma BP) have been examined using geological proxies and climate models. Whilst there is agreement between models and data, details of regional climate differ. Uncertainties in prescribed forcings and in proxy data, limit the utility of the interval to understand the dynamics of a warmer than present climate or evaluate models. This uncertainty comes, in part, from the reconstruction of a time slab rather than a time slice, where forcings required by climate models can be more adequately constrained. Here we describe the rationale and approach for identifying a time slice(s) for Pliocene environmental reconstruction. A time slice centred on 3.205 Ma BP (3.204 to 3.207 Ma BP) has been identified as a priority for investigation. It is a warm interval characterised by a negative benthic oxygen isotope excursion (0.21-0.23‰) centred on Marine Isotope Stage KM5c (KM5.3). It occurred during a period of orbital forcing which was very similar to present-day. Climate model simulations indicate that proxy temperature estimates are unlikely to be significantly affected by orbital forcing for at least a precession cycle centred on the time slice, with the North Atlantic being an important exception. As a result, uncertainties in the chronological control of proxy records will only be moderately detrimental to the synthesis of temperature data. Furthermore, proxy estimates are already able to restrict the carbon dioxide increase in the atmosphere to <120 ppmv above the pre-industrial concentration, and sea-level rise to ~22 m ± 10 m higher than present-day.

  6. SLICE/MARC-O: Description of Services. Second Revised Edition.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Libraries, Oklahoma City.

    Following the discussions of: what is SLICE, what is MARC, what is MARC-O, and what is SLICE/MARC-O are descriptions of the five services offered by SLICE/MARC-O. These services are: (1) cataloging data search and print, (2) MARC record and search and copy, (3) standard S.D.I. current awareness, (4) custom S.D.I. current awareness and (5) SLICE…

  7. Slice sampling technique in Bayesian extreme of gold price modelling

    NASA Astrophysics Data System (ADS)

    Rostami, Mohammad; Adam, Mohd Bakri; Ibrahim, Noor Akma; Yahya, Mohamed Hisham

    2013-09-01

    In this paper, a simulation study of Bayesian extreme values by using Markov Chain Monte Carlo via slice sampling algorithm is implemented. We compared the accuracy of slice sampling with other methods for a Gumbel model. This study revealed that slice sampling algorithm offers more accurate and closer estimates with less RMSE than other methods . Finally we successfully employed this procedure to estimate the parameters of Malaysia extreme gold price from 2000 to 2011.

  8. A novel method for air drying aloe leaf slices by covering with filter papers as a shrink-proof layer.

    PubMed

    Kim, S A; Baek, J H; Lee, S J; Choi, S Y; Hur, W; Lee, S Y

    2009-01-01

    To prevent the shrinkage of aloe vera slices during air drying, a method utilizing a shrink-proof layer was developed. The sample was configured of whole leaf aloe slices, where 1 side or both sides were covered with filter papers as shrink-proof layers. After air drying by varying the air temperature and the slice thickness, the drying characteristics, as well as several quality factors of the dried aloe vera leaf slices, were analyzed. In the simulation of the drying curves, the modified Page model showed the best fitness, representing a diffusion-controlled drying mechanism. Nonetheless, there was a trace of a constant-rate drying period in the samples dried by the method. Shrinkage was greatly reduced, and the rehydration ratios increased by approximately 50%. Scanning electron microscopic analysis revealed that the surface structure of original fibrous form was well sustained. FT-IR characteristics showed that the dried samples could sustain aloe polysaccharide acetylation. Furthermore, the functional properties of the dried slices including water holding capacity, swelling, and fat absorption capability were improved, and polysaccharide retention levels increased by 20% to 30%. Therefore, we concluded that application of shrink-proof layers on aloe slices provides a novel way to overcome the shrinkage problems commonly found in air drying, thereby improving their functional properties with less cost. Practical Application: This research article demonstrates a novel air drying method using shrink-proof layers to prevent the shrinkage of aloe slices. We analyzed extensively the characteristics of shrinkage mechanism and physical properties of aloe flesh gels in this drying system. We concluded that this method can be a beneficial means to retain the functional properties of dried aloe, and a potential alternative to freeze drying, which is still costly. PMID:20492108

  9. Constant mean curvature slicings of Kantowski-Sachs spacetimes

    SciTech Connect

    Heinzle, J. Mark

    2011-04-15

    We investigate existence, uniqueness, and the asymptotic properties of constant mean curvature (CMC) slicings in vacuum Kantowski-Sachs spacetimes with positive cosmological constant. Since these spacetimes violate the strong energy condition, most of the general theorems on CMC slicings do not apply. Although there are in fact Kantowski-Sachs spacetimes with a unique CMC foliation or CMC time function, we prove that there also exist Kantowski-Sachs spacetimes with an arbitrary number of (families of) CMC slicings. The properties of these slicings are analyzed in some detail.

  10. Analysis of Slice Transverse Emittance Evolution ina Photocathode RF Gun

    SciTech Connect

    Huang, Z.; Ding, Y.; Qiang, J.; /LBL, Berkeley

    2007-10-17

    The slice transverse emittance of an electron beam is of critical significance for an x-ray FEL. In a photocathode RF gun, the slice transverse emittance is not only determined by the emission process, but also influenced strongly by the non-linear space charge effect. In this paper, we study the slice transverse emittance evolution in a photocathode RF gun using a simple model that includes effects of RF acceleration, focusing, and space charge force. The results are compared with IMPACT-T space charge simulations and may be used to understand the development of the slice emittance in an RF gun.

  11. Characterization of masses in digital breast tomosynthesis: Comparison of machine learning in projection views and reconstructed slices

    SciTech Connect

    Chan, Heang-Ping; Wu Yita; Sahiner, Berkman; Wei, Jun; Helvie, Mark A.; Zhang Yiheng; Moore, Richard H.; Kopans, Daniel B.; Hadjiiski, Lubomir; Way, Ted

    2010-07-15

    Purpose: In digital breast tomosynthesis (DBT), quasi-three-dimensional (3D) structural information is reconstructed from a small number of 2D projection view (PV) mammograms acquired over a limited angular range. The authors developed preliminary computer-aided diagnosis (CADx) methods for classification of malignant and benign masses and compared the effectiveness of analyzing lesion characteristics in the reconstructed DBT slices and in the PVs. Methods: A data set of MLO view DBT of 99 patients containing 107 masses (56 malignant and 51 benign) was collected at the Massachusetts General Hospital with IRB approval. The DBTs were obtained with a GE prototype system which acquired 11 PVs over a 50 deg. arc. The authors reconstructed the DBTs at 1 mm slice interval using a simultaneous algebraic reconstruction technique. The region of interest (ROI) containing the mass was marked by a radiologist in the DBT volume and the corresponding ROIs on the PVs were derived based on the imaging geometry. The subsequent processes were fully automated. For classification of masses using the DBT-slice approach, the mass on each slice was segmented by an active contour model initialized with adaptive k-means clustering. A spiculation likelihood map was generated by analysis of the gradient directions around the mass margin and spiculation features were extracted from the map. The rubber band straightening transform (RBST) was applied to a band of pixels around the segmented mass boundary. The RBST image was enhanced by Sobel filtering in the horizontal and vertical directions, from which run-length statistics texture features were extracted. Morphological features including those from the normalized radial length were designed to describe the mass shape. A feature space composed of the spiculation features, texture features, and morphological features extracted from the central slice alone and seven feature spaces obtained by averaging the corresponding features from three to 19

  12. Cutting work in thick section cryomicrotomy.

    PubMed

    Saubermann, A J; Riley, W D; Beeuwkes, R

    1977-09-01

    The forces during cryosectioning were measured using miniature strain gauges attached to a load cell fitted to the drive arm of the Porter-Blum MT-2 cryomicrotome. Work was calculated and the data normalized to a standard (1 mm X 1 mm X 0.5 micrometer) section. Thermal energy generated was also calculated. Five parameters were studied: cutting angle, thickness, temperature, hardness, and block shape. Force patterns could be divided into three major groups thought to represent cutting (Type I), large fracture planes greater than 10 micrometer in length (Type II), and small fracture planes less than 10 micrometer in length (Type III). Type I and Type II produced satisfactory sections. Work in cutting ranged from an average of 78.4 muJ to 568.8 muJ. Cutting angle and temperature had the greatest effect on sectioning. Heat generated would be sufficient to cause through-section melting for 0.5 micrometer thick sections assuming the worst possible case, namely that all heat went into the section without loss. Presence of a Type II pattern (large fracture pattern) is thought to be presumptive evidence against thawing. PMID:606833

  13. Slicing the Torus: Obscuring Structures in Quasars

    NASA Astrophysics Data System (ADS)

    Elvis, Martin

    2012-07-01

    Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate "obscuring torus", that begins at the radius at which the most refractive dust can remain solid. The most famous form of this torus is a donut-shaped region of molecular gas with a large scale-height. While this model is elegant and accounts for many phenomena at once, it does not hold up to detailed tests. Instead the obscuration in AGNs must occur on a wide range of scales and be due to a minimum of three physically distinct absorbers. Slicing the "torus" into these three regions will allow interesting physics of the AGN to be extracted.

  14. Slicing AADL Specifications for Model Checking

    NASA Technical Reports Server (NTRS)

    Odenbrett, Maximilian; Nguyen, Viet Yen; Noll, Thomas

    2010-01-01

    To combat the state-space explosion problem in model checking larger systems, abstraction techniques can be employed. Here, methods that operate on the system specification before constructing its state space are preferable to those that try to minimize the resulting transition system as they generally reduce peak memory requirements. We sketch a slicing algorithm for system specifications written in (a variant of) the Architecture Analysis and Design Language (AADL). Given a specification and a property to be verified, it automatically removes those parts of the specification that are irrelevant for model checking the property, thus reducing the size of the corresponding transition system. The applicability and effectiveness of our approach is demonstrated by analyzing the state-space reduction for an example, employing a translator from AADL to Promela, the input language of the SPIN model checker.

  15. Rapid manifestation of reactive astrogliosis in acute hippocampal brain slices

    PubMed Central

    Takano, Takahiro; He, Wei; Han, Xiaoning; Wang, Fushun; Xu, Qiwu; Wang, Xiaohai; Oberheim Bush, Nancy Ann; Cruz, Nancy; Dienel, Gerald A.; Nedergaard, Maiken

    2014-01-01

    A flurry of studies over the past decade has shown that astrocytes play a more active role in neural function than previously recognized. Hippocampal slices prepared from young rodent pups have served as a popular model for studying the pathways by which astrocytes participate in synaptic transmission. It is, however, not known how well astrocytes tolerate traumatic injury and hypoxia, which are unavoidable when preparing acute slices. We here show that astrocytes exhibit striking changes in expression of several receptors and structural proteins, including re-expression of the developmental marker nestin within 90 min following preparation of live vibratome slices. Moreover, immunoelectron microscopy showed a 2.7-fold loss of astrocytic processes in acute hippocampal slices prepared from GFAP-GFP reporter mice. A sharp decrease in the number of mitochondria was also noted in acute slices, concurrently with an increase in mitochondrial size. Glycogen content decreased 3-fold upon slice preparation and did not recover despite stable recordings of field EPSC. Analysis of Ca2+ signaling showed that astrocytic responses to purine receptor and mGluR5 agonists differed in slice vs. in vivo. These observations suggest that the functional properties and the fine structure of astrocytes in slices may be reflective of early stages of reactive gliosis and should be confirmed in vivo when possible. PMID:24272704

  16. Rapid manifestation of reactive astrogliosis in acute hippocampal brain slices.

    PubMed

    Takano, Takahiro; He, Wei; Han, Xiaoning; Wang, Fushun; Xu, Qiwu; Wang, Xiaohai; Oberheim Bush, Nancy Ann; Cruz, Nancy; Dienel, Gerald A; Nedergaard, Maiken

    2014-01-01

    A flurry of studies over the past decade has shown that astrocytes play a more active role in neural function than previously recognized. Hippocampal slices prepared from young rodent pups have served as a popular model for studying the pathways by which astrocytes participate in synaptic transmission. It is, however, not known how well astrocytes tolerate traumatic injury and hypoxia, which are unavoidable when preparing acute slices. We here showed that astrocytes exhibit striking changes in expression of several receptors and structural proteins, including re-expression of the developmental marker nestin within 90 min following preparation of live vibratome slices. Moreover, immunoelectron microscopy showed a 2.7-fold loss of astrocytic processes in acute hippocampal slices prepared from glial fibrillary acidic protein-green fluorescent protein reporter mice. A sharp decrease in the number of mitochondria was also noted in acute slices, concurrently with an increase in mitochondrial size. Glycogen content decreased 3-fold upon slice preparation and did not recover despite stable recordings of field excitatory postsynaptic current. Analysis of Ca(2+) signaling showed that astrocytic responses to purine receptor and mGluR5 agonists differed in slice versus in vivo. These observations suggest that the functional properties and the fine structure of astrocytes in slices may be reflective of early stages of reactive gliosis and should be confirmed in vivo when possible. PMID:24272704

  17. PHYSIOLOGICAL CHANGES IN PINEAPPLE SLICES TREATED WITH ANTIBROWNING AGENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The physiological responses of pineapple slices to antibrowning agents have been studied. Slices were immersed for 2 minutes in solutions of Isoascorbic acid (IAA) 0.1 M, ascorbic acid (AA) 0.05 M or acetyl cysteine (AC) 0.05 M, packaged in polystyrene trays, prior to storage for up to 14 days at 1...

  18. Mathematical Modeling of Thin Layer Microwave Drying of Taro Slices

    NASA Astrophysics Data System (ADS)

    Kumar, Vivek; Sharma, H. K.; Singh, K.

    2016-03-01

    The present study investigated the drying kinetics of taro slices precooked in different medium viz water (WC), steam (SC) and Lemon Solution (LC) and dried at different microwave power 360, 540 and 720 W. Drying curves of all precooked slices at all microwave powers showed falling rate period along with a very short accelerating period at the beginning of the drying. At all microwave powers, higher drying rate was observed for LC slices as compared to WC and SC slices. To select a suitable drying curve, seven thin-layer drying models were fitted to the experimental data. The data revealed that the Page model was most adequate in describing the microwave drying behavior of taro slices precooked in different medium. The highest effective moisture diffusivity value of 2.11 × 10-8 m2/s was obtained for LC samples while the lowest 0.83 × 10-8 m2/s was obtained for WC taro slices. The activation energy (E a ) of LC taro slices was lower than the E a of WC and SC taro slices.

  19. Modeling surface transfer of L. monocytogenes on salami during slicing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes has been implicated in several listeriosis outbreaks linked to the consumption of pre-sliced ready-to-eat (RTE) deli meats, which has drawn considerable attention in regard to possible cross-contamination during slicing operation at retail and food service environment. Salami...

  20. Target recognition for ladar range image using slice image

    NASA Astrophysics Data System (ADS)

    Xia, Wenze; Han, Shaokun; Wang, Liang

    2015-12-01

    A shape descriptor and a complete shape-based recognition system using slice images as geometric feature descriptor for ladar range images are introduced. A slice image is a two-dimensional image generated by three-dimensional Hough transform and the corresponding mathematical transformation. The system consists of two processes, the model library construction and recognition. In the model library construction process, a series of range images are obtained after the model object is sampled at preset attitude angles. Then, all the range images are converted into slice images. The number of slice images is reduced by clustering analysis and finding a representation to reduce the size of the model library. In the recognition process, the slice image of the scene is compared with the slice image in the model library. The recognition results depend on the comparison. Simulated ladar range images are used to analyze the recognition and misjudgment rates, and comparison between the slice image representation method and moment invariants representation method is performed. The experimental results show that whether in conditions without noise or with ladar noise, the system has a high recognition rate and low misjudgment rate. The comparison experiment demonstrates that the slice image has better representation ability than moment invariants.

  1. Cariprazine delays ouabain-evoked epileptiform spikes and loss of activity in rat hippocampal slices.

    PubMed

    El-Mallakh, Rif S; Payne, Ralphiel S; Schurr, Avital; Gao, Yonglin; Lei, Zhemin; Kiss, Béla; Gyertyán, István; Adham, Nika

    2015-09-30

    In the only bipolar cycling in vitro model, rat hippocampal slices are treated with the sodium pump inhibitor ouabain, which induces epileptiform activity, followed by refractory activity loss that recovers and cycles back to epileptiform activity. Thus, clinical cycling seen in patients with bipolar disorder is modeled on a cellular level as alternating hyperactivity and hypoactivity interspersed with normal activity. In this study, we tested the ability of cariprazine a new antipsychotic candidate to block ouabain-induced changes in rat hippocampal slices. Cycling of population spikes and epileptiform bursts was evoked using an extracellular stimulation electrode located in the Schaeffer collaterals of 400-µm-thick rat hippocampal slices treated with ouabain (3.3μM) alone or in combination with cariprazine (1, 5, 25, and 50µM). Responses were recorded using an extracellular electrode placed in the cell body layer of the CA1 region. Cariprazine 25 and 50µM delayed ouabain-induced epileptiform burst onset and subsequent activity loss. Lower cariprazine concentrations were ineffective. Cariprazine delays the onset of ouabain-induced epileptiform bursts and the loss of spiking activity similarly to that previously demonstrated with the mood stabilizer lithium. These results suggest that cariprazine may have therapeutic potential for treatment of bipolar disorder. PMID:26160196

  2. A survey of program slicing for software engineering

    NASA Technical Reports Server (NTRS)

    Beck, Jon

    1993-01-01

    This research concerns program slicing which is used as a tool for program maintainence of software systems. Program slicing decreases the level of effort required to understand and maintain complex software systems. It was first designed as a debugging aid, but it has since been generalized into various tools and extended to include program comprehension, module cohesion estimation, requirements verification, dead code elimination, and maintainence of several software systems, including reverse engineering, parallelization, portability, and reuse component generation. This paper seeks to address and define terminology, theoretical concepts, program representation, different program graphs, developments in static slicing, dynamic slicing, and semantics and mathematical models. Applications for conventional slicing are presented, along with a prognosis of future work in this field.

  3. Seamless Ligation Cloning Extract (SLiCE) cloning method.

    PubMed

    Zhang, Yongwei; Werling, Uwe; Edelmann, Winfried

    2014-01-01

    SLiCE (Seamless Ligation Cloning Extract) is a novel cloning method that utilizes easy to generate bacterial cell extracts to assemble multiple DNA fragments into recombinant DNA molecules in a single in vitro recombination reaction. SLiCE overcomes the sequence limitations of traditional cloning methods, facilitates seamless cloning by recombining short end homologies (15-52 bp) with or without flanking heterologous sequences and provides an effective strategy for directional subcloning of DNA fragments from bacterial artificial chromosomes or other sources. SLiCE is highly cost-effective and demonstrates the versatility as a number of standard laboratory bacterial strains can serve as sources for SLiCE extract. We established a DH10B-derived E. coli strain expressing an optimized λ prophage Red recombination system, termed PPY, which facilitates SLiCE with very high efficiencies. PMID:24395368

  4. Organotypic slice culture of the hypothalamic paraventricular nucleus of rat

    PubMed Central

    Cho, Eun Seong; Lee, So Yeong; Park, Jae-Yong; Hong, Seong-Geun

    2007-01-01

    Organotypic slice cultures have been developed as an alternative to acute brain slices because the neuronal viability and synaptic connectivity in these cultures can be preserved well for a prolonged period of time. This study evaluated a stationary organotypic slice culture developed for the hypothalamic paraventricular nucleus (PVN) of rat. The results showed that the slice cultures maintain the typical shape of the nucleus, the immunocytochemical signals for oxytocin, vasopressin, and corticotropin-releasing hormone, and the electrophysiological properties of PVN neurons for up to 3 weeks in vitro. The PVN neurons in the culture expressed the green fluorescent protein gene that had been delivered by the adenoviral vectors. The results indicate that the cultured slices preserve the properties of the PVN neurons, and can be used in longterm studies on these neurons in vitro. PMID:17322769

  5. Evidence for liquefaction identified in peeled slices of Holocene deposits along the Lower Columbia River, Washington

    USGS Publications Warehouse

    Takada, K.; Atwater, B.F.

    2004-01-01

    Peels made from 10 geoslices beneath a riverbank at Washington's Hunting Island, 45 km inland from the Pacific coast, aid in identifying sand that liquefied during prehistoric earthquakes of estimated magnitude 8-9 at the Cascadia subduction zone. Each slice was obtained by driving sheetpile and a shutter plate to depths of 6-8 m. The resulting sample, as long as 8 m, had a trapezoidal cross section 42-55 cm by 8 cm. The slicing created few artifacts other than bending and smearing at slice edges. Each slice is dominated by well-stratified sand and mud deposited by the tidal Columbia River. Nearly 90% of the sand is distinctly laminated. The sand contains mud beds as thick as 0.5 m and at least 20 m long, and it is capped by a mud bed that contains a buried soil that marks the 1700 Cascadia earthquake of estimated magnitude 9. Every slice intersected sills and dikes of fluidized sand, and many slices show folds and faults as well. Sills, which outnumber dikes, mostly follow and locally invade the undersides of mud beds. The mud beds probably impeded diffuse upward flow of water expelled from liquefied sand. Trapped beneath mud beds, this water flowed laterally, destroyed bedding by entraining (fluidizing) sand, and locally scoured the overlying mud. Horizontal zones of folded sand extend at least 10 or 20 m, and some contain low-angle faults. Many of the folds probably formed while sand was weakened by liquefaction. The low-angle faults may mark the soles of river-bottom slumps or lateral spreads. As many as four great Cascadia earthquakes in the past 2000 yr contributed to the intrusions, folds, and faults. This subsurface evidence for fluid escape and deformation casts doubt on maximum accelerations that were previously inferred from local absence of liquefaction features at the ground surface along the Columbia River. The geosliced evidence for liquefaction abounds not only beneath banks riddled with dikes but also beneath banks in which dikes are absent. Such

  6. Evaluation of slice shear force as an objective method of assessing beef longissimus tenderness.

    PubMed

    Shackelford, S D; Wheeler, T L; Koohmaraie, M

    1999-10-01

    Experiments were conducted to develop an optimal protocol for measurement of slice shear force (SSF) and to evaluate SSF as an objective method of assessing beef longissimus tenderness. Whereas six cylindrical, 1.27-cm-diameter cores are typically removed from each steak for Warner-Bratzler shear force (WBSF) determination, a single 1-cm-thick, 5-cm-long slice is removed from the lateral end of each longissimus steak for SSF. For either technique, samples are removed parallel to the muscle fiber orientation and sheared across the fibers. Whereas WBSF uses a V-shaped blade, SSF uses a flat blade with the same thickness (1.016 mm) and degree of bevel (half-round) on the shearing edge. In Exp. 1, longissimus steaks were acquired from 60 beef carcasses to determine the effects of belt grill cooking rate (very rapid vs. rapid) and conditions of SSF measurement (hot vs cold) on the relationship of SSF with trained sensory panel (TSP) tenderness rating. Slice shear force was more strongly correlated with TSP tenderness rating when SSF measurement was conducted immediately after cooking (r = -.74 to -.76) than when steaks were chilled (24 h, 4 degrees C) before SSF measurement (r = -.57 to -.72). When SSF measurement was conducted immediately after cooking, the relationship of SSF with TSP tenderness rating did not differ among the belt grill cooking protocols used to cook the SSF steak. In Exp. 2, longissimus steaks were acquired from 479 beef carcasses to compare the ability of SSF and WBSF of 1.27-cm-diameter cores to predict TSP tenderness ratings. Slice shear force was more strongly correlated with sensory panel tenderness rating than was WBSF (r = -.82 vs -.77). In Exp. 3, longissimus steaks were acquired from 110 beef carcasses to evaluate the repeatability (.91) of SSF over a broad range of tenderness. Slice shear force is a more rapid, more accurate, and technically less difficult technique than WBSF. Use of the SSF technique could facilitate the collection of

  7. Software Method for Computed Tomography Cylinder Data Unwrapping, Re-slicing, and Analysis

    NASA Technical Reports Server (NTRS)

    Roth, Don J.

    2013-01-01

    A software method has been developed that is applicable for analyzing cylindrical and partially cylindrical objects inspected using computed tomography (CT). This method involves unwrapping and re-slicing data so that the CT data from the cylindrical object can be viewed as a series of 2D sheets (or flattened onion skins ) in addition to a series of top view slices and 3D volume rendering. The advantages of viewing the data in this fashion are as follows: (1) the use of standard and specialized image processing and analysis methods is facilitated having 2D array data versus a volume rendering; (2) accurate lateral dimensional analysis of flaws is possible in the unwrapped sheets versus volume rendering; (3) flaws in the part jump out at the inspector with the proper contrast expansion settings in the unwrapped sheets; and (4) it is much easier for the inspector to locate flaws in the unwrapped sheets versus top view slices for very thin cylinders. The method is fully automated and requires no input from the user except proper voxel dimension from the CT experiment and wall thickness of the part. The software is available in 32-bit and 64-bit versions, and can be used with binary data (8- and 16-bit) and BMP type CT image sets. The software has memory (RAM) and hard-drive based modes. The advantage of the (64-bit) RAM-based mode is speed (and is very practical for users of 64-bit Windows operating systems and computers having 16 GB or more RAM). The advantage of the hard-drive based analysis is one can work with essentially unlimited-sized data sets. Separate windows are spawned for the unwrapped/re-sliced data view and any image processing interactive capability. Individual unwrapped images and un -wrapped image series can be saved in common image formats. More information is available at http://www.grc.nasa.gov/WWW/OptInstr/ NDE_CT_CylinderUnwrapper.html.

  8. How thick do consumers' want their meat and how thick do they get it? The case of deep-fried breaded beef.

    PubMed

    Ferraris, Daniela C; Libertino, Luciano M; Rodríguez, Graciela L; Hough, Guillermo E

    2013-08-01

    The main objective was to estimate the optimum thickness of meat from a consumers' perspective. Breaded beef (known as "milanesa" in Spanish speaking countries and as "schnitzels" in Austria) is a food product prepared with a slice of meat that is dipped in beaten egg to then be covered in bread crumbs; thus prepared it is fried. This product was used as a case study. Breaded beef was evaluated in three different stages: raw slice of meat, appearance of meat after frying, and during mastication. Breaded beef prepared with meat of varying thicknesses were presented to consumers who evaluated if the thicknesses were too thin, ok or too thick. Survival analysis statistics were used to estimate the optimum thicknesses. Results for each stage were: raw slice of meat = 6.7 ± 0.2 mm, appearance of the cut fried breaded beef = 8.4 ± 0.3 mm and during mastication = 7.6 ± 0.3 mm. The average thickness of the meat cut by butchers for breaded beef was 5.9 mm, not too far from the optimum. However, the average thickness of the meat in the breaded beef ready for frying sold by the same butchers 3.7 mm, clearly thinner than the optimum. PMID:23524882

  9. Effect of Temperature Gradient on Thick Film Selective Emitter Emittance

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.; Good, Brian S.; Clark, Eric B.; Chen, Zheng

    1997-01-01

    A temperature gradient across a thick (greater than or equal to .1 mm) film selective emitter will produce a significant reduction in the spectral emittance from the no temperature gradient case. Thick film selective emitters of rare earth doped host materials such as yttrium-aluminum-garnet (YAG) are examples where temperature gradient effects are important. In this paper a model is developed for the spectral emittance assuming a linear temperature gradient across the film. Results of the model indicate that temperature gradients will result in reductions the order of 20% or more in the spectral emittance.

  10. A Unified Approach to Diffusion Direction Sensitive Slice Registration and 3-D DTI Reconstruction From Moving Fetal Brain Anatomy

    PubMed Central

    Fogtmann, Mads; Seshamani, Sharmishtaa; Kroenke, Christopher; Cheng, Xi; Chapman, Teresa; Wilm, Jakob; Rousseau, François

    2014-01-01

    This paper presents an approach to 3-D diffusion tensor image (DTI) reconstruction from multi-slice diffusion weighted (DW) magnetic resonance imaging acquisitions of the moving fetal brain. Motion scatters the slice measurements in the spatial and spherical diffusion domain with respect to the underlying anatomy. Previous image registration techniques have been described to estimate the between slice fetal head motion, allowing the reconstruction of 3-D a diffusion estimate on a regular grid using interpolation. We propose Approach to Unified Diffusion Sensitive Slice Alignment and Reconstruction (AUDiSSAR) that explicitly formulates a process for diffusion direction sensitive DW-slice-to-DTI-volume alignment. This also incorporates image resolution modeling to iteratively deconvolve the effects of the imaging point spread function using the multiple views provided by thick slices acquired in different anatomical planes. The algorithm is implemented using a multi-resolution iterative scheme and multiple real and synthetic data are used to evaluate the performance of the technique. An accuracy experiment using synthetically created motion data of an adult head and a experiment using synthetic motion added to sedated fetal monkey dataset show a significant improvement in motion-trajectory estimation compared to a state-of-the-art approaches. The performance of the method is then evaluated on challenging but clinically typical in utero fetal scans of four different human cases, showing improved rendition of cortical anatomy and extraction of white matter tracts. While the experimental work focuses on DTI reconstruction (second-order tensor model), the proposed reconstruction framework can employ any 5-D diffusion volume model that can be represented by the spatial parameterizations of an orientation distribution function. PMID:24108711

  11. Sliced Inverse Regression for Time Series Analysis

    NASA Astrophysics Data System (ADS)

    Chen, Li-Sue

    1995-11-01

    In this thesis, general nonlinear models for time series data are considered. A basic form is x _{t} = f(beta_sp{1} {T}X_{t-1},beta_sp {2}{T}X_{t-1},... , beta_sp{k}{T}X_ {t-1},varepsilon_{t}), where x_{t} is an observed time series data, X_{t } is the first d time lag vector, (x _{t},x_{t-1},... ,x _{t-d-1}), f is an unknown function, beta_{i}'s are unknown vectors, varepsilon_{t }'s are independent distributed. Special cases include AR and TAR models. We investigate the feasibility applying SIR/PHD (Li 1990, 1991) (the sliced inverse regression and principal Hessian methods) in estimating beta _{i}'s. PCA (Principal component analysis) is brought in to check one critical condition for SIR/PHD. Through simulation and a study on 3 well -known data sets of Canadian lynx, U.S. unemployment rate and sunspot numbers, we demonstrate how SIR/PHD can effectively retrieve the interesting low-dimension structures for time series data.

  12. Thin-slice perception develops slowly.

    PubMed

    Balas, Benjamin; Kanwisher, Nancy; Saxe, Rebecca

    2012-06-01

    Body language and facial gesture provide sufficient visual information to support high-level social inferences from "thin slices" of behavior. Given short movies of nonverbal behavior, adults make reliable judgments in a large number of tasks. Here we find that the high precision of adults' nonverbal social perception depends on the slow development, over childhood, of sensitivity to subtle visual cues. Children and adult participants watched short silent clips in which a target child played with Lego blocks either in the (off-screen) presence of an adult or alone. Participants judged whether the target was playing alone or not; that is, they detected the presence of a social interaction (from the behavior of one participant in that interaction). This task allowed us to compare performance across ages with the true answer. Children did not reach adult levels of performance on this task until 9 or 10 years of age, and we observed an interaction between age and video reversal. Adults and older children benefitted from the videos being played in temporal sequence, rather than reversed, suggesting that adults (but not young children) are sensitive to natural movement in social interactions. PMID:22417920

  13. Effects of immunological castration (Improvest) on further processed belly characteristics and commercial bacon slicing yields of finishing pigs.

    PubMed

    Kyle, J M; Bohrer, B M; Schroeder, A L; Matulis, R J; Boler, D D

    2014-09-01

    Objectives were to compare fresh belly characteristics, further processed belly characteristics, and commercial bacon slicing yields of immunologically castrated (IC) barrows, IC barrows fed ractopamine hydrochloride (IC+RAC), physically castrated (PC) barrows, intact males, and gilts. One hundred eighty-eight bellies from pigs housed in single sex pens (n = 48) slaughtered at 130 kg ending live weight were evaluated for flop distance, length, width, thickness, and fatty acid composition. Bellies were injected, thermally processed, and sliced according to standard protocols at a USDA federally inspected facility. Complete slices were sorted by trained plant personnel. Then, sliced bellies were individually packaged to maintain anatomical orientation. The effects of treatments were analyzed as a generalized linear mixed model with pen of pigs serving as the experimental unit for all comparisons. Belly thickness was not different (P ≥ 0.11) in bellies from IC barrows (3.74 cm) compared with bellies from IC+RAC (3.60 cm), PC barrows (3.94 cm), or gilts (3.64 cm); however, bellies were 0.42 cm thicker (P < 0.01) in IC barrows compared with intact males. Iodine value was not different (P ≥ 0.06) in bellies from IC barrows (68.26) compared with bellies from IC+RAC (69.78), PC barrows (67.55), or gilts (69.45); however, iodine value was 2.32 units less (P < 0.01) in IC barrows compared with intact males. Green weight was not different (P ≥ 0.09) in bellies from IC barrows (4.88 kg) compared with bellies from IC+RAC (5.11 kg), PC barrows (5.10 kg), or gilts (4.79 kg); however, green weight was 0.56 kg greater (P < 0.0001) in IC barrows compared with intact males. Pump uptake and cooked yield was not different (P ≥ 0.15) among treatment groups. Slicing yield (as a percentage of green weight) was decreased (P ≤ 0.01) in bellies from IC barrows (93.61%) compared with bellies from PC barrows (98.42%) or gilts (98.19%); however, slicing yield was not different (P

  14. Gastric Wall Thickness in Sleeve Gastrectomy Patients: Thickness Variation of the Gastric Wall.

    PubMed

    van Rutte, Pim W J; Naagen, Bertus J; Spek, Marinus; Jakimowicz, Jack J; Nienhuijs, Simon W

    2015-11-01

    The sleeve gastrectomy has been accepted as a primary bariatric procedure. One of the most feared complications is staple line leakage. It is important to use the right staple sizes to minimize the risk of leak. Knowledge of gastric thickness is important. The goal of this study was to measure the thickness of the gastric wall after elimination of the gastric folds in the mucosa. An electronic thickness gauge was developed that measured the anterior and posterior wall of the fresh stomach specimen together at 5 points at a pressure based on the finger pressure necessary to flatten the gastric folds. Thirty-three fresh specimens were measured. The mean compression pressure was 714 grams, and no difference was found between the 5 measure points. There was a significant difference in stomach wall thickness. The gastric antrum was more than 1 mm thicker than the fundus. No difference was found between BMI groups <40 Kg/m2, 40-50 Kg/m2, or >50 Kg/m2. No bleeding occurred, leakage occurred in 1 case. There is a significant difference in thickness of the stomach wall between the gastric fundus and the antrum. A pressure 2.5 times lower than applied in prior studies was necessary to achieve full tissue compression. Choosing thinner staple sizes for the gastric fundus might be the optimal technique for compression. However, there are several additional factors that influence the risk of staple line leaks. PMID:26680415

  15. Adiabatic slice-selective excitation for surface coils.

    PubMed

    Shen, J; Rothman, D L

    1997-01-01

    A novel RF pulse designed to perform a diabatic slice-selective excitation for surface coils (ASSESS) is proposed in which Bzero gradient is modulated in concert with RF frequency modulation. Within the selected slice, the principles of BIR4 pulses are employed to obtain well-defined, pure-phase and self-refocused spin rotation of arbitrary flip angles despite the presence of high B1 inhomogeneity produced by surface coils. Outside the slice, advantage is taken of the B1 field to dephase equilibrium magnetization to achieve slice selection or outer-volume suppression. This scheme should be useful for many localization techniques. Quaternion analysis of the overall propagator of the proposed pulse and numerical simulations using Bloch equations are performed. The pulse is tested experimentally on a phantom sample. PMID:9169211

  16. Computed tomographic coronary angiography: how many slices do you need?

    PubMed Central

    Peebles, C

    2006-01-01

    While increasing the number of slices in multislice computed tomography clearly brings benefits in terms of detecting significant coronary disease, heavy calcification remains a problem, as does the high radiation burden PMID:16614268

  17. Eight-Bit-Slice GaAs General Processor Circuit

    NASA Technical Reports Server (NTRS)

    Weissman, John; Gauthier, Robert V.

    1989-01-01

    Novel GaAs 8-bit slice enables quick and efficient implementation of variety of fast GaAs digital systems ranging from central processing units of computers to special-purpose processors for communications and signal-processing applications. With GaAs 8-bit slice, designers quickly configure and test hearts of many digital systems that demand fast complex arithmetic, fast and sufficient register storage, efficient multiplexing and routing of data words, and ease of control.

  18. Multiple-bipolar-tap tunable spectrum sliced microwave photonic filter.

    PubMed

    Chen, Tong; Yi, Xiaoke; Huang, Thomas; Minasian, Robert A

    2010-12-01

    A spectrum sliced microwave photonic signal processor structure, which is all-fiber based and features simplicity, together with the ability to realize tunability, reconfigurability, bipolar taps, and multiple-tap rf filtering, is presented. It is based on thermally controlled optical slicing filters induced into two linearly chirped fiber Bragg gratings. Experimental results demonstrate the realization of versatile microwave photonic filters with frequency tunable, reconfiguration, and bipolar-tap generation capabilities. PMID:21124570

  19. PRECISION-CUT SLICE CULTURE METHOD FOR RAT PLACENTA

    PubMed Central

    Gilligan, Jeffrey; Tong, Ming; Longato, Lisa; de la Monte, Suzanne M; Gundogan, Fusun

    2011-01-01

    Primary trophoblasts, placental explants, and cell line cultures are commonly used to investigate placental development, physiology, and pathology, particularly in relation to pregnancy outcomes. Organotypic slice cultures are increasingly used in other systems because they maintain the normal three-dimensional tissue architecture and have all cell types represented. Herein, we demonstrate the utility of the precision-cut placental slice culture model for studying trophoblastic diseases. PMID:22079834

  20. Tryptophan availability modulates serotonin release from rat hypothalamic slices

    NASA Technical Reports Server (NTRS)

    Schaechter, Judith D.; Wurtman, Richard J.

    1989-01-01

    The relationship between the tryptophan availability and serononin release from rat hypothalamus was investigated using a new in vitro technique for estimating rates at which endogenous serotonin is released spontaneously or upon electrical depolarization from hypothalamic slices superfused with a solution containing various amounts of tryptophan. It was found that the spontaneous, as well as electrically induced, release of serotonin from the brain slices exhibited a dose-dependent relationship with the tryptophan concentration of the superfusion medium.

  1. Preservation of low slice emittance in bunch compressors

    NASA Astrophysics Data System (ADS)

    Bettoni, S.; Aiba, M.; Beutner, B.; Pedrozzi, M.; Prat, E.; Reiche, S.; Schietinger, T.

    2016-03-01

    Minimizing the dilution of the electron beam emittance is crucial for the performance of accelerators, in particular for free electron laser facilities, where the length of the machine and the efficiency of the lasing process depend on it. Measurements performed at the SwissFEL Injector Test Facility revealed an increase in slice emittance after compressing the bunch even for moderate compression factors. The phenomenon was experimentally studied by characterizing the dependence of the effect on beam and machine parameters relevant for the bunch compression. The reproduction of these measurements in simulation required the use of a 3D beam dynamics model along the bunch compressor that includes coherent synchrotron radiation. Our investigations identified transverse effects, such as coherent synchrotron radiation and transverse space charge as the sources of the observed emittance dilution, excluding other effects, such as chromatic effects on single slices or spurious dispersion. We also present studies, both experimental and simulation based, on the effect of the optics mismatch of the slices on the variation of the slice emittance along the bunch. After a corresponding reoptimization of the beam optics in the test facility we reached slice emittances below 200 nm for the central slices along the longitudinal dimension with a moderate increase up to 300 nm in the head and tail for a compression factor of 7.5 and a bunch charge of 200 pC, equivalent to a final current of 150 A, at about 230 MeV energy.

  2. Thickness microscopy based on photothermal radiometry for the measurement of thin films.

    PubMed

    Wang, Liping; Prekel, Helmut; Liu, Hengbiao; Deng, Yanzhuo; Hu, Jiming; Goch, Gert

    2009-03-01

    The photothermal detection technique is an innovative and non-contact method to investigate the properties of films on workpieces. This paper describes a novel experimental set-up for thickness microscopy based on photothermal radiometry. The correlation between the thermal wave signal and the film thickness is deduced and evaluated to determine the film thickness with a lateral resolution of less than 1mm. Results indicate that the thickness microscopy is a useful method to characterize thin films and has the potential to be applied in-process. PMID:19046925

  3. Corneal thickness in glaucoma.

    PubMed

    De Cevallos, E; Dohlman, C H; Reinhart, W J

    1976-02-01

    The central corneal stromal thickness of patients with open angle glaucoma, secondary glaucoma (the majority aphakic), or a history of unilateral acute angle closure glaucoma were measured and compared with the stromal thickness of a group of normal patients. In open angle glaucoma, there was a small but significant increase in the average stromal thickness. This thickness increase was, in all likelihood, due to an abnormal function of the endothelium in this disease since the level of the intraocular pressure did not seem to be a factor. There was no correlation between stromal thickness and duration of the glaucoma or type of anti-glaucomatous medication. Most cases of secondary glaucome, controlled medically or not, had markedly increased corneal thickness, again, most likely, due to endothelial damage rather than to level of intraocular pressure. After an angle closure attack, permanent damage to the cornea was found to be rare. PMID:1247273

  4. The Correlation Between Age and Bleeding Volume in Haemorrhagic Stroke Using Multi Slice CT at District Hospitals in Jakarta.

    PubMed

    Saefudin, Tatan; Apriantoro, Nursama Heru; Hidayat, Ekaputra Syarif; Purnamawati, Schandra

    2016-04-01

    Haemorrhagic Stroke is a common disease in Indonesia. The best imaging modality for this disease is Multi Slice Computed Tomography Scanning (MSCT), as it may help strengthening the diagnosis as well as determining the brain bleeding volume. This study aimed to show correlation between bleeding volume of the brain and patient's age using cross-sectional approach. The 68 samples in this study were taken from secondary data from Head CT Scan of Haemorrhagic Stroke cases.  Brain bleeding volume is the dependent variable, obtained through slice thickness of 5 mm and ABC/2 method with software measurement in MSCT Scan device. The independent variable of this study is the patient's age. The result of the study was the average brain's bleeding volume of 21.76 ml ± 2.48 ml (range of 1.04 ml to 94.73 ml).The slice thickness using ABC/2 method, has a significant correlation with brain's bleeding volume in MSCT Scan examination, with correlation coefficient value r of 0.79. Brain bleeding volume in patients who have ages lower than 50 years and more or equal to 50 years were (18.93 ± 3.26) ml and (23.53 ± 3.47) ml respectively. There is no correlation between age and brain's bleeding volume in haemorrhagic stroke cases, with p value of 0.18, r = 0.19. PMID:26573030

  5. The Correlation Between Age and Bleeding Volume in Haemorrhagic Stroke Using Multi Slice CT at District Hospitals in Jakarta

    PubMed Central

    Saefudin, Tatan; Apriantoro, Nursama Heru; Hidayat, Ekaputra Syarif; Purnamawati, Schandra

    2016-01-01

    Haemorrhagic Stroke is a common disease in Indonesia. The best imaging modality for this disease is Multi Slice Computed Tomography Scanning (MSCT), as it may help strengthening the diagnosis as well as determining the brain bleeding volume. This study aimed to show correlation between bleeding volume of the brain and patient’s age using cross-sectional approach. The 68 samples in this study were taken from secondary data from Head CT Scan of Haemorrhagic Stroke cases. Brain bleeding volume is the dependent variable, obtained through slice thickness of 5 mm and ABC/2 method with software measurement in MSCT Scan device. The independent variable of this study is the patient’s age. The result of the study was the average brain’s bleeding volume of 21.76 ml ± 2.48 ml (range of 1.04 ml to 94.73 ml). The slice thickness using ABC/2 method, has a significant correlation with brain’s bleeding volume in MSCT Scan examination, with correlation coefficient value r of 0.79. Brain bleeding volume in patients who have ages lower than 50 years and more or equal to 50 years were (18.93 ± 3.26) ml and (23.53 ± 3.47) ml respectively. There is no correlation between age and brain’s bleeding volume in haemorrhagic stroke cases, with p value of 0.18, r = 0.19. PMID:26573030

  6. Lead Thickness Measurements

    SciTech Connect

    Rucinski, R.; /Fermilab

    1998-02-16

    The preshower lead thickness applied to the outside of D-Zero's superconducting solenoid vacuum shell was measured at the time of application. This engineering documents those thickness measurements. The lead was ordered in sheets 0.09375-inch and 0.0625-inch thick. The tolerance on thickness was specified to be +/- 0.003-inch. The sheets all were within that thickness tolerance. The nomenclature for each sheet was designated 1T, 1B, 2T, 2B where the numeral designates it's location in the wrap and 'T' or 'B' is short for 'top' or 'bottom' half of the solenoid. Micrometer measurements were taken at six locations around the perimeter of each sheet. The width,length, and weight of each piece was then measured. Using an assumed pure lead density of 0.40974 lb/in{sup 3}, an average sheet thickness was calculated and compared to the perimeter thickness measurements. In every case, the calculated average thickness was a few mils thinner than the perimeter measurements. The ratio was constant, 0.98. This discrepancy is likely due to the assumed pure lead density. It is not felt that the perimeter is thicker than the center regions. The data suggests that the physical thickness of the sheets is uniform to +/- 0.0015-inch.

  7. Quantitative transfer of Salmonella Typhimurium LT2 during mechanical slicing of tomatoes as impacted by multiple processing variables.

    PubMed

    Wang, Haiqiang; Ryser, Elliot T

    2016-10-01

    Slicing of fresh produce can readily lead to pathogen cross-contamination with pre-sliced tomatoes having been linked to multistate outbreaks of salmonellosis in the United States. This study aimed to assess the impact of multiple processing variables on quantitative transfer of Salmonella during simulated commercial slicing of tomatoes. One red round tomato was inoculated with Salmonella Typhimurium LT2 at ~5logCFU/g and sliced using a manual or electric slicer, followed by 20 uninoculated tomatoes. Thereafter, the distribution of Salmonella on inoculated and uninoculated tomato slices was evaluated along with the transfer of Salmonella from different parts of the slicer. The impact of multiple processing variables including post-contamination hold time (0 and 30min), tomato wetness (dry and wet), processing room temperature (23, 10 and 4°C), slice thickness (0.48, 0.64, and 0.95cm), tomato variety (Torero, Rebelski, and Bigdena) and pre-wash treatment (no wash, tap water, and chlorine) was also investigated. The data were fitted to a two-parameter exponential decay model (Y=A⋅exp(BX)) with the percentage of Salmonella transferred to 20 uninoculated tomatoes then calculated. Salmonella populations on nine inoculated tomato slices ranged from 4.6±0.2 to 5.5±0.3logCFU/g, with higher populations on slices from the blossom and stem scar ends. However, Salmonella transfer to the previously uninoculated slices was similar (P>0.05), ranging from 2.1±0.2 to 3.4±0.2logCFU/g. Significantly fewer salmonellae transferred from the blade (3.4±0.4 log CFU, P≤0.05) than from the back and bottom plates (4.7±0.3 log CFU) or the whole manual slicer (5.2±0.2 log CFU) to the 20 uninoculated tomatoes. However, the blade was the primary contributor to Salmonella transfer for the electric slicer. Post-contamination hold time, processing temperature and tomato slice thickness did not significantly impact (P>0.05) the Salmonella transfer rate (parameter B) or the overall

  8. Silicon Ingot Casting: Heat Exchanger Method. Multi-wire Slicing: Fixed Abrasine Slicing Technique, Phase 3

    NASA Technical Reports Server (NTRS)

    Schmid, F.; Khattak, C. P.

    1979-01-01

    Ingot casting was scaled up to 16 cm by 16 cm square cross section size and ingots weighing up to 8.1 kg were cast. The high degree of crystallinity was maintained in the large ingot. For large sizes, the nonuniformity of heat treatment causes chipping of the surface of the ingot. Progress was made in the development of a uniform graded structure in the silica crucibles. The high speed slicer blade-head weight was reduced to 37 pounds, allowing surface speeds of up to 500 feet per minute. Slicing of 10 cm diameter workpieces at these speeds increased the through-put of the machine to 0.145 mm/min.

  9. Preparation and Applications of Organotypic Thymic Slice Cultures.

    PubMed

    Sood, Aditi; Dong, Mengqi; Melichar, Heather J

    2016-01-01

    Thymic selection proceeds in a unique and highly organized thymic microenvironment resulting in the generation of a functional, self-tolerant T cell repertoire. In vitro models to study T lineage commitment and development have provided valuable insights into this process. However, these systems lack the complete three-dimensional thymic milieu necessary for T cell development and, therefore, are incomplete approximations of in vivo thymic selection. Some of the challenges related to modeling T cell development can be overcome by using in situ models that provide an intact thymic microenvironment that fully supports thymic selection of developing T cells. Thymic slice organotypic cultures complement existing in situ techniques. Thymic slices preserve the integrity of the thymic cortical and medullary regions and provide a platform to study development of overlaid thymocytes of a defined developmental stage or of endogenous T cells within a mature thymic microenvironment. Given the ability to generate ~20 slices per mouse, thymic slices present a unique advantage in terms of scalability for high throughput experiments. Further, the relative ease in generating thymic slices and potential to overlay different thymic subsets or other cell populations from diverse genetic backgrounds enhances the versatility of this method. Here we describe a protocol for the preparation of thymic slices, isolation and overlay of thymocytes, and dissociation of thymic slices for flow cytometric analysis. This system can also be adapted to study non-conventional T cell development as well as visualize thymocyte migration, thymocyte-stromal cell interactions, and TCR signals associated with thymic selection by two-photon microscopy. PMID:27585240

  10. Thickness scalability of large volume cadmium zinc telluride high resolution radiation detectors

    NASA Astrophysics Data System (ADS)

    Awadalla, S. A.; Chen, H.; Mackenzie, J.; Lu, P.; Iniewski, K.; Marthandam, P.; Redden, R.; Bindley, G.; He, Z.; Zhang, F.

    2009-06-01

    This work focuses on the thickness scalability of traveling heater method (THM) grown CdZnTe crystals to produce large volume detectors with optimized spectroscopic performance. To meet this challenge, we have tuned both our THM growth process, to grow 75 mm diameter ingots, and our postgrowth annealing process. We have increased the thickness of our sliced wafers from 6 to 12 and 18 mm allowing the production of 10 and 15 mm thick detectors. As the detectors' thickness is scaled up, the energy resolution of both types, as pseudo-Frisch grid and pixelated monolithic detectors showed no degradation indicating improved materials uniformity and transport properties.

  11. Thick film hydrogen sensor

    DOEpatents

    Hoffheins, Barbara S.; Lauf, Robert J.

    1995-01-01

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

  12. Thick film hydrogen sensor

    DOEpatents

    Hoffheins, B.S.; Lauf, R.J.

    1995-09-19

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors. 8 figs.

  13. Education and "Thick" Epistemology

    ERIC Educational Resources Information Center

    Kotzee, Ben

    2011-01-01

    In this essay Ben Kotzee addresses the implications of Bernard Williams's distinction between "thick" and "thin" concepts in ethics for epistemology and for education. Kotzee holds that, as in the case of ethics, one may distinguish between "thick" and "thin" concepts of epistemology and, further, that this distinction points to the importance of…

  14. Effect of ceramic thickness and composite bases on stress distribution of inlays--a finite element analysis.

    PubMed

    Durand, Letícia Brandão; Guimarães, Jackeline Coutinho; Monteiro Junior, Sylvio; Baratieri, Luiz Narciso

    2015-01-01

    The purpose of this study was to determine the effect of cavity depth, ceramic thickness, and resin bases with different elastic modulus on von Mises stress patterns of ceramic inlays. Tridimensional geometric models were developed with SolidWorks image software. The differences between the models were: depth of pulpal wall, ceramic thickness, and presence of composite bases with different thickness and elastic modulus. The geometric models were constrained at the proximal surfaces and base of maxillary bone. A load of 100 N was applied. The stress distribution pattern was analyzed with von Mises stress diagrams. The maximum von Mises stress values ranged from 176 MPa to 263 MPa and varied among the 3D-models. The highest von Mises stress value was found on models with 1-mm-thick composite resin base and 1-mm-thick ceramic inlay. Intermediate values (249-250 MPa) occurred on models with 2-mm-thick composite resin base and 1-mm-thick ceramic inlay and 1-mm-thick composite resin base and 2-mm-thick ceramic inlay. The lowest values were observed on models restored exclusively with ceramic inlay (176 MPa to 182 MPa). It was found that thicker inlays distribute stress more favorably and bases with low elastic modulus increase stress concentrations on the internal surface of the ceramic inlay. The increase of ceramic thickness tends to present more favorable stress distribution, especially when bonded directly onto the cavity without the use of supporting materials. When the use of a composite base is required, composite resin with high elastic modulus and reduced thickness should be preferred. PMID:25831105

  15. Short pulse generation by laser slicing at NSLSII

    SciTech Connect

    Yu, L.; Blednykh, A.; Guo, W.; Krinsky, S.; Li, Y.; Shaftan, T.; Tchoubar, O.; Wang, G.; Willeke, F.; Yang, L.

    2011-03-28

    We discuss an upgrade R&D project for NSLSII to generate sub-pico-second short x-ray pulses using laser slicing. We discuss its basic parameters and present a specific example for a viable design and its performance. Since the installation of the laser slicing system into the storage ring will break the symmetry of the lattice, we demonstrate it is possible to recover the dynamical aperture to the original design goal of the ring. There is a rapid growth of ultrafast user community interested in science using sub-pico-second x-ray pulses. In BNL's Short Pulse Workshop, the discussion from users shows clearly the need for a sub-pico-second pulse source using laser slicing method. In the proposal submitted following this workshop, NSLS team proposed both hard x-ray and soft x-ray beamlines using laser slicing pulses. Hence there is clearly a need to consider the R&D efforts of laser slicing short pulse generation at NSLSII to meet these goals.

  16. Rapid and quantitative discrimination of tumour cells on tissue slices

    NASA Astrophysics Data System (ADS)

    Huang, Kai-Wen; Chieh, Jen-Jie; Liao, Shu-Hsien; Wei, Wen-Chun; Hsiao, Pei-Yi; Yang, Hong-Chang; Horng, Herng-Er

    2016-06-01

    After a needle biopsy, immunohistochemistry is generally used to stain tissue slices for clinically confirming tumours. Currently, tissue slices are immersed in a bioprobe-linked fluorescent reagent for several minutes, washed to remove the unbound reagent, and then observed using a fluorescence microscope. However, the observation must be performed by experienced pathologists, and producing a qualitative analysis is time consuming. Therefore, this study proposes a novel scanning superconducting quantum interference device biosusceptometry (SSB) method for avoiding these drawbacks. First, stain reagents were synthesised for the dual modalities of fluorescent and magnetic imaging by combining iron-oxide magnetic nanoparticles and the currently used fluorescent reagent. The reagent for the proposed approach was stained using the same procedure as that for the current fluorescent reagent, and tissue slices were rapidly imaged using the developed SSB for obtaining coregistered optical and magnetic images. Analysing the total intensity of magnetic spots in SSB images enables quantitatively determining the tumour cells of tissue slices. To confirm the magnetic imaging results, a traditional observation methodology entailing the use of a fluorescence microscope was also performed as the gold standard. This study determined high consistency between the fluorescent and magnetic spots in different regions of the tissue slices, demonstrating the feasibility of the proposed approach, which will benefit future clinical pathology.

  17. Rapid and quantitative discrimination of tumour cells on tissue slices.

    PubMed

    Huang, Kai-Wen; Chieh, Jen-Jie; Liao, Shu-Hsien; Wei, Wen-Chun; Hsiao, Pei-Yi; Yang, Hong-Chang; Horng, Herng-Er

    2016-06-10

    After a needle biopsy, immunohistochemistry is generally used to stain tissue slices for clinically confirming tumours. Currently, tissue slices are immersed in a bioprobe-linked fluorescent reagent for several minutes, washed to remove the unbound reagent, and then observed using a fluorescence microscope. However, the observation must be performed by experienced pathologists, and producing a qualitative analysis is time consuming. Therefore, this study proposes a novel scanning superconducting quantum interference device biosusceptometry (SSB) method for avoiding these drawbacks. First, stain reagents were synthesised for the dual modalities of fluorescent and magnetic imaging by combining iron-oxide magnetic nanoparticles and the currently used fluorescent reagent. The reagent for the proposed approach was stained using the same procedure as that for the current fluorescent reagent, and tissue slices were rapidly imaged using the developed SSB for obtaining coregistered optical and magnetic images. Analysing the total intensity of magnetic spots in SSB images enables quantitatively determining the tumour cells of tissue slices. To confirm the magnetic imaging results, a traditional observation methodology entailing the use of a fluorescence microscope was also performed as the gold standard. This study determined high consistency between the fluorescent and magnetic spots in different regions of the tissue slices, demonstrating the feasibility of the proposed approach, which will benefit future clinical pathology. PMID:27138705

  18. Organotypic slice cultures of human gastric and esophagogastric junction cancer.

    PubMed

    Koerfer, Justus; Kallendrusch, Sonja; Merz, Felicitas; Wittekind, Christian; Kubick, Christoph; Kassahun, Woubet T; Schumacher, Guido; Moebius, Christian; Gaßler, Nikolaus; Schopow, Nikolas; Geister, Daniela; Wiechmann, Volker; Weimann, Arved; Eckmann, Christian; Aigner, Achim; Bechmann, Ingo; Lordick, Florian

    2016-07-01

    Gastric and esophagogastric junction cancers are heterogeneous and aggressive tumors with an unpredictable response to cytotoxic treatment. New methods allowing for the analysis of drug resistance are needed. Here, we describe a novel technique by which human tumor specimens can be cultured ex vivo, preserving parts of the natural cancer microenvironment. Using a tissue chopper, fresh surgical tissue samples were cut in 400 μm slices and cultivated in 6-well plates for up to 6 days. The slices were processed for routine histopathology and immunohistochemistry. Cytokeratin stains (CK8, AE1/3) were applied for determining tumor cellularity, Ki-67 for proliferation, and cleaved caspase-3 staining for apoptosis. The slices were analyzed under naive conditions and following 2-4 days in vitro exposure to 5-FU and cisplatin. The slice culture technology allowed for a good preservation of tissue morphology and tumor cell integrity during the culture period. After chemotherapy exposure, a loss of tumor cellularity and an increase in apoptosis were observed. Drug sensitivity of the tumors could be assessed. Organotypic slice cultures of gastric and esophagogastric junction cancers were successfully established. Cytotoxic drug effects could be monitored. They may be used to examine mechanisms of drug resistance in human tissue and may provide a unique and powerful ex vivo platform for the prediction of treatment response. PMID:27073068

  19. Fractal Segmentation and Clustering Analysis for Seismic Time Slices

    NASA Astrophysics Data System (ADS)

    Ronquillo, G.; Oleschko, K.; Korvin, G.; Arizabalo, R. D.

    2002-05-01

    Fractal analysis has become part of the standard approach for quantifying texture on gray-tone or colored images. In this research we introduce a multi-stage fractal procedure to segment, classify and measure the clustering patterns on seismic time slices from a 3-D seismic survey. Five fractal classifiers (c1)-(c5) were designed to yield standardized, unbiased and precise measures of the clustering of seismic signals. The classifiers were tested on seismic time slices from the AKAL field, Cantarell Oil Complex, Mexico. The generalized lacunarity (c1), fractal signature (c2), heterogeneity (c3), rugosity of boundaries (c4) and continuity resp. tortuosity (c5) of the clusters are shown to be efficient measures of the time-space variability of seismic signals. The Local Fractal Analysis (LFA) of time slices has proved to be a powerful edge detection filter to detect and enhance linear features, like faults or buried meandering rivers. The local fractal dimensions of the time slices were also compared with the self-affinity dimensions of the corresponding parts of porosity-logs. It is speculated that the spectral dimension of the negative-amplitude parts of the time-slice yields a measure of connectivity between the formation's high-porosity zones, and correlates with overall permeability.

  20. SU-E-I-10: Investigation On Detectability of a Small Target for Different Slice Direction of a Volumetric Cone Beam CT Image

    SciTech Connect

    Lee, C; Han, M; Baek, J

    2015-06-15

    Purpose: To investigate the detectability of a small target for different slice direction of a volumetric cone beam CT image and its impact on dose reduction. Methods: Analytic projection data of a sphere object (1 mm diameter, 0.2/cm attenuation coefficient) were generated and reconstructed by FDK algorithm. In this work, we compared the detectability of the small target from four different backprojection Methods: hanning weighted ramp filter with linear interpolation (RECON 1), hanning weighted ramp filter with Fourier interpolation (RECON2), ramp filter with linear interpolation (RECON 3), and ramp filter with Fourier interpolation (RECON4), respectively. For noise simulation, 200 photons per measurement were used, and the noise only data were reconstructed using FDK algorithm. For each reconstructed volume, axial and coronal slice were extracted and detection-SNR was calculated using channelized Hotelling observer (CHO) with dense difference-of-Gaussian (D-DOG) channels. Results: Detection-SNR of coronal images varies for different backprojection methods, while axial images have a similar detection-SNR. Detection-SNR{sup 2} ratios of coronal and axial images in RECON1 and RECON2 are 1.33 and 1.15, implying that the coronal image has a better detectability than axial image. In other words, using coronal slices for the small target detection can reduce the patient dose about 33% and 15% compared to using axial slices in RECON 1 and RECON 2. Conclusion: In this work, we investigated slice direction dependent detectability of a volumetric cone beam CT image. RECON 1 and RECON 2 produced the highest detection-SNR, with better detectability in coronal slices. These results indicate that it is more beneficial to use coronal slice to improve detectability of a small target in a volumetric cone beam CT image. This research was supported by the MSIP (Ministry of Science, ICT and Future Planning), Korea, under the IT Consilience Creative Program (NIPA-2014-H0201

  1. Effect of selective laser trabeculoplasty on macular thickness

    PubMed Central

    Koc, Mustafa; Durukan, Irfan; Koban, Yaran; Ceran, Basak Bastanci; Ayar, Orhan; Ekinci, Metin; Yilmazbas, Pelin

    2015-01-01

    Background To investigate the effects of selective laser trabeculoplasty (SLT) on macular thickness change. Methods Forty eyes of 40 consecutive patients with uncontrolled primary open-angle glaucoma with medical treatment were included in this prospective study. SLT was performed to the inferior 180°, and macular thickness was measured. Data were collected before SLT, and 1 week and 1 month after SLT. Macular thickness evaluation was performed in five quadrants, the central 1 mm quadrant (fovea = F), the nasal 3 mm quadrant surrounding F (NQ), temporal quadrant, superior quadrant (SQ), and inferior quadrant (IQ). The preoperative and postoperative thicknesses were compared. Results There was an increase in macular thickness in the NQ, IQ, and SQ on the first week after SLT compared to preoperative measurements. On the other hand, there was no significant increase in the F and temporal quadrant. On the first month after SLT, thickness in the NQ, IQ, and SQ was back to preoperative measurements, and there was no significant change between the preoperative measurements in any quadrant. Conclusion There was no significant increase in macular thickness shortly after SLT in our study. PMID:26719665

  2. Perineal body anatomy in living women: 3-D analysis using thin-slice magnetic resonance imaging

    PubMed Central

    Larson, Kindra A.; Yousuf, Aisha; Lewicky-Gaupp, Christina; Fenner, Dee E.; DeLancey, John O.L.

    2012-01-01

    Objective To describe a framework for visualizing the perineal body's complex anatomy using thin-slice MR imaging. Study Design Two mm-thick MR images were acquired in 11 women with normal pelvic support and no incontinence/prolapse symptoms. Anatomic structures were analyzed in axial, sagittal and coronal slices. 3-D models were generated from these images. Results Three distinct perineal body regions are visible on MRI: (1) a superficial region at the level of the vestibular bulb, (2) a mid region at the proximal end of the superficial transverse perineal muscle, and (3) a deep region at the level of the midurethra and puborectalis muscle. Structures are best visualized on axial scans while cranio-caudal relationships are appreciated on sagittal scans. The 3-D model further clarifies inter-relationships. Conclusion Advances in MR technology allow visualization of perineal body anatomy in living women and development of 3D models which enhance our understanding of its three different regions: superficial, mid and deep. PMID:21055513

  3. Fluid dynamic lateral slicing of high tensile strength carbon nanotubes.

    PubMed

    Vimalanathan, Kasturi; Gascooke, Jason R; Suarez-Martinez, Irene; Marks, Nigel A; Kumari, Harshita; Garvey, Christopher J; Atwood, Jerry L; Lawrance, Warren D; Raston, Colin L

    2016-01-01

    Lateral slicing of micron length carbon nanotubes (CNTs) is effective on laser irradiation of the materials suspended within dynamic liquid thin films in a microfluidic vortex fluidic device (VFD). The method produces sliced CNTs with minimal defects in the absence of any chemical stabilizers, having broad length distributions centred at ca 190, 160 nm and 171 nm for single, double and multi walled CNTs respectively, as established using atomic force microscopy and supported by small angle neutron scattering solution data. Molecular dynamics simulations on a bent single walled carbon nanotube (SWCNT) with a radius of curvature of order 10 nm results in tearing across the tube upon heating, highlighting the role of shear forces which bend the tube forming strained bonds which are ruptured by the laser irradiation. CNT slicing occurs with the VFD operating in both the confined mode for a finite volume of liquid and continuous flow for scalability purposes. PMID:26965728

  4. Unstable periodic orbits in human epileptic hippocampal slices.

    PubMed

    Pen-Ning Yu; Min-Chi Hsiao; Dong Song; Liu, Charles Y; Heck, Christi N; Millett, David; Berger, Theodore W

    2014-01-01

    Inter-ictal activity is studied in hippocampal slices resected from patients with epilepsy using local field potential recording. Inter-ictal activity in the dentate gyrus (DG) is induced by high-potassium (8 mM), low-magnesium (0.25 mM) aCSF with additional 100 μM 4-aminopyridine(4-AP). The dynamics of the inter-ictal activity is investigated by developing the first return map with inter-pulse intervals. Unstable periodic orbits (UPOs) are detected in the hippocampal slice at the DG area according to both the topological recurrence method and the periodic orbit transform method. Surrogate analysis suggests the presence of UPOs in hippocampal slices from patients with epilepsy. This finding also suggests that inter-ictal activity is a chaotic system and will allow us to apply chaos control techniques to manipulate inter-ictal activity. PMID:25571314

  5. Approach to combined-function magnets via symplectic slicing

    NASA Astrophysics Data System (ADS)

    Titze, M.

    2016-05-01

    In this article we describe how to obtain symplectic "slice" maps for combined-function magnets, by using a method of generating functions. A feature of this method is that one can use an unexpanded and unsplit Hamiltonian. From such a slice map we obtain a first-order map which is symplectic at the closed orbit. We also obtain a symplectic kick map. Both results were implemented into the widely used program MAD-X to regain, in particular, the twiss parameters for the sliced model of the Proton Synchrotron at CERN. In addition, we obtain recursion equations for symplectic maps of general time-dependent Hamiltonians, which might be useful even beyond the scope of accelerator physics.

  6. Fluid dynamic lateral slicing of high tensile strength carbon nanotubes

    PubMed Central

    Vimalanathan, Kasturi; Gascooke, Jason R.; Suarez-Martinez, Irene; Marks, Nigel A.; Kumari, Harshita; Garvey, Christopher J.; Atwood, Jerry L.; Lawrance, Warren D.; Raston, Colin L.

    2016-01-01

    Lateral slicing of micron length carbon nanotubes (CNTs) is effective on laser irradiation of the materials suspended within dynamic liquid thin films in a microfluidic vortex fluidic device (VFD). The method produces sliced CNTs with minimal defects in the absence of any chemical stabilizers, having broad length distributions centred at ca 190, 160 nm and 171 nm for single, double and multi walled CNTs respectively, as established using atomic force microscopy and supported by small angle neutron scattering solution data. Molecular dynamics simulations on a bent single walled carbon nanotube (SWCNT) with a radius of curvature of order 10 nm results in tearing across the tube upon heating, highlighting the role of shear forces which bend the tube forming strained bonds which are ruptured by the laser irradiation. CNT slicing occurs with the VFD operating in both the confined mode for a finite volume of liquid and continuous flow for scalability purposes. PMID:26965728

  7. Drying kinetics and colour change of lemon slices

    NASA Astrophysics Data System (ADS)

    Darvishi, Hosain; Khoshtaghaza, Mohammad H.; Minaei, Saeid

    2014-03-01

    The effect of microwave-convective heating on drying characteristics and colour change of lemon slices was investigated. The drying experiments were carried out at 180, 360, 540 and 720Wand at 22°C, with air velocity of 1ms-1. The values of effective moisture diffusivity were found to be in the range between 1.87 10-8 and 3.95 10-8 m2 s-1, and the activation energy was estimated to be 10.91 Wg-1. The drying data were fitted with ten mathematical models available in the literature. The model describing drying kinetics of lemon slices in the best way was found. The colour change of the dried lemon slices was analysed and considered as a quality index affecting the drying quality of the product. The values of lightness/darkness, yellowness/blueness and hue angle increased, while the value of redness/greenness decreased with increasing microwave power.

  8. Plastinated heart slices aid echocardiographic interpretation in the dog.

    PubMed

    Gómez, Alejandro; Del Palacio, Josefa F; Latorre, Rafael; Henry, Robert W; Sarriá, Ricardo; Albors, Octavio López

    2012-01-01

    Our aim was to compare plastinated sections of the canine heart with corresponding two-dimensional (2D) echocardiographic images. Thirteen dog hearts were fixed by dilation and then processed by the S10 silicon plastination method (Biodur). Two dogs without evidence of cardiac disease were imaged using 2D echocardiography so as to obtain a complete series of the standard right and left parasternal images, which were compared with corresponding plastinated slices obtained by knife sectioning of the hearts. The plastinated slices revealed the internal anatomy of the heart with great detail and were particularly useful to display the spatial relationship between complex anatomic structures. The plastinated slices corresponded accurately with the echocardiographic images. Because of the dilation of the right heart during the fixation process, it was not possible to obtain plastinated specimens in ventricular systole. This paper may be a reference atlas for assisting 2D echocardiography interpretation. PMID:22092521

  9. Fluid dynamic lateral slicing of high tensile strength carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Vimalanathan, Kasturi; Gascooke, Jason R.; Suarez-Martinez, Irene; Marks, Nigel A.; Kumari, Harshita; Garvey, Christopher J.; Atwood, Jerry L.; Lawrance, Warren D.; Raston, Colin L.

    2016-03-01

    Lateral slicing of micron length carbon nanotubes (CNTs) is effective on laser irradiation of the materials suspended within dynamic liquid thin films in a microfluidic vortex fluidic device (VFD). The method produces sliced CNTs with minimal defects in the absence of any chemical stabilizers, having broad length distributions centred at ca 190, 160 nm and 171 nm for single, double and multi walled CNTs respectively, as established using atomic force microscopy and supported by small angle neutron scattering solution data. Molecular dynamics simulations on a bent single walled carbon nanotube (SWCNT) with a radius of curvature of order 10 nm results in tearing across the tube upon heating, highlighting the role of shear forces which bend the tube forming strained bonds which are ruptured by the laser irradiation. CNT slicing occurs with the VFD operating in both the confined mode for a finite volume of liquid and continuous flow for scalability purposes.

  10. Comparative evaluation of efficacy of EndoVac irrigation system to Max-I probe in removing smear layer in apical 1 mm and 3 mm of root canal: An in vitro scanning electron microscope study

    PubMed Central

    Dua, Ankur; Dua, Deepti

    2015-01-01

    Background: The purpose of this study was to compare the efficacy of EndoVac irrigation system and side-vented closed ended needle (Max-I probe) in removing smear layer from root canals at 1 mm and 3 mm from working length using ProTaper rotary instrumentation. Materials and Methods: A total of 50 freshly extracted maxillary central incisors were randomly divided into two groups after complete cleaning and shaping with ProTaper rotary files. In one group, final irrigation was performed with EndoVac system while in other group, final irrigation was done with a 30 gauge Max-I probe. 3% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetracetic acid were used as final irrigants in all teeth. During instrumentation, 1 ml of 3% NaOCl was used for irrigation after each rotary instrument in the similar manner as in final irrigation. After instrumentation and irrigation, teeth were sectioned longitudinally into buccal and palatal halves and viewed under scanning electron microscope for evaluation of smear layer. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U-test. (P < 0.05) Results: At 3 mm level, there was no significant difference between two groups. At 1 mm level, EndoVac group showed significantly better smear layer removal compared with Max-I probe (P = 0.0001). Conclusion: EndoVac system results in better smear layer removal at 1 mm from working length when compared to Max-I probe irrigation. PMID:25709673

  11. Fast parallel algorithm for slicing STL based on pipeline

    NASA Astrophysics Data System (ADS)

    Ma, Xulong; Lin, Feng; Yao, Bo

    2016-04-01

    In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can't make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl's law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson's law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.

  12. Fast parallel algorithm for slicing STL based on pipeline

    NASA Astrophysics Data System (ADS)

    Ma, Xulong; Lin, Feng; Yao, Bo

    2016-05-01

    In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can't make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl's law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson's law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.

  13. Thin slice expert testimony and mock trial deliberations.

    PubMed

    Parrott, Caroline Titcomb; Brodsky, Stanley L; Wilson, Jennifer Kelly

    2015-01-01

    This study examined impressions of expert witness testimony in a not guilty by reason of insanity defense on two outcomes: witness's credibility and verdict. Borrowing in part from the "thin slice" methodology, we assessed outcomes in a 2 (deliberating vs. non-deliberating jurors) × 3 (length of videotaped testimony) between-subjects design. In 30 mock juries, 188 participants viewed the testimony by a forensic psychologist; then half of the juries deliberated. Thinner slices of the testimony were defined by the lower (30s long) and upper (5 min long) temporal bounds in the literature. The third, fuller testimony condition was 10 min long and served as the accuracy marker for the shorter sliced exposures. We aimed to explore potential consequences to jurors relying on impressions of the expert, and his or her opinion, and to test that effect post deliberation. Accounting for deliberation, brief impressions of expert credibility generally exerted a similar influence on credibility to fuller considerations. The essential finding was that a two-way interaction emerged from time slice and deliberation on verdict for jurors in the 30s condition. Overall, predictive accuracy was found in the 5 min slice, yet accuracy was not supported in the predictions based on the shortest slice. Individually-formed impressions are not likely to translate to the verdict ballot post-deliberation. Instead, brief impressions are likely to be heavily influenced by deliberation. Implications for understanding how impression-based testimony evaluations translate from the jury box to the deliberation room are discussed. PMID:26346686

  14. Origami of thick panels

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Peng, Rui; You, Zhong

    2015-07-01

    Origami patterns, including the rigid origami patterns in which flat inflexible sheets are joined by creases, are primarily created for zero-thickness sheets. In order to apply them to fold structures such as roofs, solar panels, and space mirrors, for which thickness cannot be disregarded, various methods have been suggested. However, they generally involve adding materials to or offsetting panels away from the idealized sheet without altering the kinematic model used to simulate folding. We develop a comprehensive kinematic synthesis for rigid origami of thick panels that differs from the existing kinematic model but is capable of reproducing motions identical to that of zero-thickness origami. The approach, proven to be effective for typical origami, can be readily applied to fold real engineering structures.

  15. Measuring coal thickness

    NASA Technical Reports Server (NTRS)

    Barker, C.; Blaine, J.; Geller, G.; Robinson, R.; Summers, D.; Tyler, J.

    1980-01-01

    Laboratory tested concept, for measuring thickness of overhead coal using noncontacting sensor system coupled to controller and high pressure water jet, allows mining machines to remove virtually all coal from mine roofs without danger of cutting into overlying rock.

  16. Importance of Corneal Thickness

    MedlinePlus

    ... News About Us Donate In This Section The Importance of Corneal Thickness email Send this article to ... is important because it can mask an accurate reading of eye pressure, causing doctors to treat you ...

  17. United States crustal thickness

    NASA Technical Reports Server (NTRS)

    Allenby, R. J.; Schnetzler, C. C.

    1983-01-01

    The thickness of the crust, the thickness of the basal (intermediate or lower) crustal layer, and the average velocity at the top of the mantle have been mapped using all available deep-penetrating seismic-refraction profiles in the conterminous United States and surrounding border areas. These profiles are indexed to their literature data sources. The more significant long wavelength anomalies on the three maps are briefly discussed and analyzed. An attempt to use Bouguer gravity to validate mantle structure was inconclusive.

  18. Verification of Software Product Lines with Delta-Oriented Slicing

    NASA Astrophysics Data System (ADS)

    Bruns, Daniel; Klebanov, Vladimir; Schaefer, Ina

    Software product line (SPL) engineering is a well-known approach to develop industry-size adaptable software systems. SPL are often used in domains where high-quality software is desirable; the overwhelming product diversity, however, remains a challenge for assuring correctness. In this paper, we present delta-oriented slicing, an approach to reduce the deductive verification effort across an SPL where individual products are Java programs and their relations are described by deltas. On the specification side, we extend the delta language to deal with formal specifications. On the verification side, we combine proof slicing and similarity-guided proof reuse to ease the verification process.

  19. ESPRESSO APSU: simplify the life of pupil slicing

    NASA Astrophysics Data System (ADS)

    Conconi, P.; Riva, M.; Pepe, F.; Zerbi, F. M.; Cabral, A.; Cristiani, S.; Megevand, D.; Landoni, M.; Spanó, P.

    2013-09-01

    This paper presents the Espresso Anamorphic pupil Slicer (APSU) implementation. ESPRESSO, the Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, will be installed on ESOs Very Large Telescope (VLT). In this work we will present the design and trade-off for the pupil slicing system introduced in order to increase the resolving power, effectively decreasing slit width. Its based onto simplified optical component that introduce large anamorphism while keeping low aberrations by means of cylindrical optics. We describe here the trade-off between slicing through two adjacent squared doublets and two achromatic prisms.

  20. Classification of CT-brain slices based on local histograms

    NASA Astrophysics Data System (ADS)

    Avrunin, Oleg G.; Tymkovych, Maksym Y.; Pavlov, Sergii V.; Timchik, Sergii V.; Kisała, Piotr; Orakbaev, Yerbol

    2015-12-01

    Neurosurgical intervention is a very complicated process. Modern operating procedures based on data such as CT, MRI, etc. Automated analysis of these data is an important task for researchers. Some modern methods of brain-slice segmentation use additional data to process these images. Classification can be used to obtain this information. To classify the CT images of the brain, we suggest using local histogram and features extracted from them. The paper shows the process of feature extraction and classification CT-slices of the brain. The process of feature extraction is specialized for axial cross-section of the brain. The work can be applied to medical neurosurgical systems.

  1. Interfacial stress state present in a 'thin-slice' fibre push-out test

    NASA Technical Reports Server (NTRS)

    Kallas, M. N.; Koss, D. A.; Hahn, H. T.; Hellmann, J. R.

    1992-01-01

    An analysis of the stress distributions along the fiber-matrix interface in a 'thin-slice' fiber push-out test is presented for selected test geometries. For the small specimen thicknesses often required to displace large-diameter fibers with high interfacial shear strengths, finite element analysis indicates that large bending stresses may be present. The magnitude of these stresses and their spatial distribution can be very sensitive to the test configuration. For certain test geometries, the specimen configuration itself may alter the interfacial failure process from one which initiates due to a maximum in shear stress near the top surface adjacent to the indentor, to one which involves mixed mode crack growth up from the bottom surface and/or yielding within the matrix near the interface.

  2. Multi-wire slurry wafering demonstrations. [slicing silicon ingots for solar arrays

    NASA Technical Reports Server (NTRS)

    Chen, C. P.

    1978-01-01

    Ten slicing demonstrations on a multi-wire slurry saw, made to evaluate the silicon ingot wafering capabilities, reveal that the present sawing capabilities can provide usable wafer area from an ingot 1.05m/kg (e.g. kerf width 0.135 mm and wafer thickness 0.265 mm). Satisfactory surface qualities and excellent yield of silicon wafers were found. One drawback is that the add-on cost of producing water from this saw, as presently used, is considerably higher than other systems being developed for the low-cost silicon solar array project (LSSA), primarily because the saw uses a large quantity of wire. The add-on cost can be significantly reduced by extending the wire life and/or by rescue of properly plated wire to restore the diameter.

  3. Climate variability around the first Pliocene time slice

    NASA Astrophysics Data System (ADS)

    Prescott, C.; Haywood, A.; Dolan, A. M.; Hunter, S. J.; Tindall, J.; Pope, J. O.; Pickering, S.

    2013-12-01

    Existing data/model comparisons for the mid-Pliocene (Dowsett et al., 2013) have identified specific regions of concordance and discord between climate models and proxy data. One reason for site-specific disagreement is likely related to the time (warm peak) averaged nature of the mid-Pliocene ocean temperatures provided within existing proxy syntheses. To facilitate improved data/model comparisons in the future new proxy sea surface temperature reconstructions will focus on specific time slices within the Pliocene epoch. Haywood et al. (2013) identified an initial time slice for environmental reconstruction and climate modelling centred on an interglacial event at Marine Isotope Stage KM5c (3.205 Ma). Critically, this interval displays a very near to modern orbital configuration simplifying the interpretation of proxy data and the experimental design for climate models. Nevertheless, current limitations of chronology and correlation make it likely that new proxy records will be attributable to a time range around the time slice, and may not always represent the time slice specifically. This introduces an element of uncertainty through orbital forcing around the time slice which can be investigated and quantified within a numerical climate modelling framework. The Hadley Centre Coupled Climate Model Version 3 (HadCM3) has been used to perform a series of orbital forcing sensitivity tests around the identified time slice at MIS KM5c. Simulations every 2 kyr either side of the time slice to a range +/- 20 kyr have been completed. The model results indicate that +/- 20 kyr either side of the time slice, orbital forcing generates a less than 1°C change on global MAT. One exception to this relative stability in climate is seen in the North Atlantic (a region noted for disagreement in existing Pliocene data/model comparisons). Here, ocean surface temperature variations of up to 6°C are predicted. These model responses appear to be linked to changes in ocean circulation

  4. Preparative reversed-phase high-performance liquid chromatography collection efficiency for an antimicrobial peptide on columns of varying diameters (1 mm to 9.4 mm I.D.)

    PubMed Central

    Chen, Yuxin; Mant, Colin T.; Hodges, Robert S.

    2009-01-01

    The present study examines the effect of reversed-phase high-performance liquid chromatography (RP-HPLC) column diameter (1 mm to 9.4 mm I.D.) on the one-step slow gradient preparative purification of a 26-residue synthetic antimicrobial peptide. When taken together, the semi-preparative column (9.4 mm I.D.) provided the highest yields of purified product (an average of 90.7% recovery from hydrophilic and hydrophobic impurities) over a wide range of sample load (0.75–200 mg). Columns with smaller diameters, such as narrowbore columns (150 × 2.1 mm I.D.) and microbore columns (150 × 1.0 mm I.D.), can be employed to purify peptides with reasonable recovery of purified product but the range of the crude peptide that can be applied to the column is limited. In addition, the smaller diameter columns require more extensive fraction analysis to locate the fractions of pure product than the larger diameter column with the same load. Our results show the excellent potential of the one-step slow gradient preparative protocol as a universal method for purification of synthetic peptides. PMID:17156789

  5. Conversion factors for determining organ doses received by paediatric patients in high-resolution single slice computed tomography with narrow collimation.

    PubMed

    Seidenbusch, Michael C; Harder, Dietrich; Regulla, Dieter F; Schneider, Karl

    2014-05-01

    Estimations of organ doses DT received during computed tomographic examinations are usually performed by applying conversion factors to basic dose indicators like the computed tomography dose index (CTDI) or the dose-length-product (DLP). In addition to the existing conversion factors for beam apertures of 5 mm or 10 mm, we present new DLP-DT conversion factors adapted to high-resolution CT (HRCT) examinations of infants and young children with beam apertures of the order of 1 mm and under consideration of bow tie filtration. Calculations are performed on mathematical MIRD phantoms for an age range from 0, 1, 5, 10, 15 up to (for comparison) 30 years by adapting PCXMC, a Monte Carlo algorithm originally developed by STUK (Helsinki, Finland) for dose reconstructions in projection radiography. For this purpose, each single slice CT examination is approximated by a series of corresponding virtual planar radiographies comprising all focus positions. The transformation of CT exposure parameters into exposure parameters of the series of corresponding planar radiographies is performed by a specially developed algorithm called XCT. The DLP values are evaluated using the EGSRay code. The new method is verified at a beam aperture of 10 mm by comparison with formerly published conversion factors. We show that the higher spatial resolution leads to an enhanced DLP-DT conversion factor if a small organ (e. g. thyroid gland, mammae, uterus, ovaries, testes) is exactly met by the chosen CT slice, while the conversion factor is drastically reduced if the chosen CT slice is positioned above or below the organ. This effect is utilized for dose-saving examinations with only a few single slices instead a full scan, which technique is applied in about 10% of all paediatric chest CT examinations. PMID:24630933

  6. METHOXYCHLOR METABOLISM AND VITELLOGENESIS IN MALE RAINBOW TROUT LIVER SLICES

    EPA Science Inventory

    Induction of vitellogenin (VTG) in male fish has become an accepted biomarker to xenoestrogenicity. This study utilized the male rainbow trout liver slice model to determine the estrogenicity of parent compound, methoxychlor (MXC) and metabolites, di-hydroxy methoxychlor (HPTE) a...

  7. Excitation and geometrically matched local encoding of curved slices.

    PubMed

    Weber, Hans; Gallichan, Daniel; Schultz, Gerrit; Cocosco, Chris A; Littin, Sebastian; Reichardt, Wilfried; Welz, Anna; Witschey, Walter; Hennig, Jürgen; Zaitsev, Maxim

    2013-05-01

    In this work, the concept of excitation and geometrically matched local in-plane encoding of curved slices (ExLoc) is introduced. ExLoc is based on a set of locally near-orthogonal spatial encoding magnetic fields, thus maintaining a local rectangular shape of the individual voxels and avoiding potential problems arising due to highly irregular voxel shapes. Unlike existing methods for exciting curved slices based on multidimensional radiofrequency-pulses, excitation and geometrically matched local encoding of curved slices does not require long duration or computationally expensive radiofrequency-pulses. As each encoding field consists of a superposition of potentially arbitrary (spatially linear or nonlinear) magnetic field components, the resulting field shape can be adapted with high flexibility to the specific region of interest. For extended nonplanar structures, this results in improved relevant volume coverage for fewer excited slices and thus increased efficiency. In addition to the mathematical description for the generation of dedicated encoding fields and data reconstruction, a verification of the ExLoc concept in phantom experiments and examples for in vivo curved single and multislice imaging are presented. PMID:22711656

  8. Blanching, salting and sun drying of different pumpkin fruit slices.

    PubMed

    Workneh, T S; Zinash, A; Woldetsadik, K

    2014-11-01

    The study was aimed at assessing the quality of pumpkin (Cucuribita Spp.) slices that were subjected to pre-drying treatments and drying using two drying methods (uncontrolled sun and oven) fruit accessions. Pre-drying had significant (P ≤ 0.05) effect on the quality of dried pumpkin slices. 10 % salt solution dipped pumpkin fruit slices had good chemical quality. The two-way interaction between drying methods and pre-drying treatments had significant (P ≤ 0.05) effect on chemical qualities. Pumpkin subjected to salt solution dipping treatment and oven dried had higher chemical concentrations. Among the pumpkin fruit accessions, pumpkin accession 8007 had the superior TSS, total sugar and sugar to acid ratio after drying. Among the three pre-drying treatment, salt solution dipping treatment had significant (P ≤ 0.05) effect and the most efficient pre-drying treatment to retain the quality of dried pumpkin fruits without significant chemical quality deterioration. Salt dipping treatment combined with low temperature (60 °C) oven air circulation drying is recommended to maintain quality of dried pumpkin slices. However, since direct sun drying needs extended drying time due to fluctuation in temperature, it is recommended to develop or select best successful solar dryer for use in combination with pre-drying salt dipping or blanching treatments. PMID:26396303

  9. Pyrethroid insecticides evoke neurotransmitter release from rabbit striatal slices

    SciTech Connect

    Eells, J.T.; Dubocovich, M.L.

    1988-08-01

    The effects of the synthetic pyrethroid insecticide fenvalerate ((R,S)-alpha-cyano-3-phenoxybenzyl(R,S)-2-(4-chlorophenyl)-3- methylbutyrate) on neurotransmitter release in rabbit brain slices were investigated. Fenvalerate evoked a calcium-dependent release of (/sup 3/H)dopamine and (/sup 3/H)acetylcholine from rabbit striatal slices that was concentration-dependent and specific for the toxic stereoisomer of the insecticide. The release of (/sup 3/H)dopamine and (/sup 3/H)acetylcholine by fenvalerate was modulated by D2 dopamine receptor activation and antagonized completely by the sodium channel blocker, tetrodotoxin. These findings are consistent with an action of fenvalerate on the voltage-dependent sodium channels of the presynaptic membrane resulting in membrane depolarization, and the release of dopamine and acetylcholine by a calcium-dependent exocytotic process. In contrast to results obtained in striatal slices, fenvalerate did not elicit the release of (/sup 3/H)norepinephrine or (/sup 3/H)acetylcholine from rabbit hippocampal slices indicative of regional differences in sensitivity to type II pyrethroid actions.

  10. Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside-Diameter (I.D.) saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1980-01-01

    Inside diametar wafering equipment, blades and processes were used to develop methods to produce large areas of silicon sheet. Modifications to a 16 inch STC automated saw included: programmable feed system, crystal rotating system, and STC dynatrack blade monitoring and control system. By controlling the plating operation and by grinding of the cutting edge, 16 inch ID blades with a cutting edge thickness of .22 mm can be produced. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge ID slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

  11. Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside Diameter (I.D.) saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1980-01-01

    Modifications to a 16 inch STC automated saw included: a programmable feed system; a crystal rotating system; and a STC dynatrack blade boring and control system. By controlling the plating operation and by grinding the cutting edge, 16 inch I.D. blades were produced with a cutting edge thickness of .22 mm. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge I.D. slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

  12. Liquid thickness gauge

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor)

    1988-01-01

    A method and apparatus are developed to measure the thickness of a liquid on a surface independent of liquid conductivity. Two pairs of round, corrosion resistant wires are mounted in an insulating material such that the cross-sectional area of each wire is flush with and normal to the surface. The resistance between each pair of wires is measured using two ac resistance measuring circuits, in which the ratio of the outputs of the two resistance measuring circuits is indicative of the thickness of the liquid on the surface.

  13. Minimum wafer thickness by rotated ingot ID wafering. [Inner Diameter

    NASA Technical Reports Server (NTRS)

    Chen, C. P.; Leipold, M. H.

    1984-01-01

    The efficient utilization of materials is critical to certain device applications such as silicon for photovoltaics or diodes and gallium-gadolinium-garnet for memories. A variety of slicing techniques has been investigated to minimize wafer thickness and wafer kerf. This paper presents the results of analyses of ID wafering of rotated ingots based on predicted fracture behavior of the wafer as a result of forces during wafering and the properties of the device material. The analytical model indicated that the minimum wafer thickness is controlled by the depth of surface damage and the applied cantilever force. Both of these factors should be minimized. For silicon, a minimum thickness was found to be approximately 200 x 10 - 6th m for conventional sizes of rotated ingot wafering. Fractures through the thickness of the wafer rather than through the center supporting column were found to limit the minimum wafer thickness. The model suggested that the use of a vacuum chuck on the wafer surface to enhance cleavage fracture of the center supporting core and, with silicon, by using 111-line-type ingots could have potential for reducing minimum wafer thickness.

  14. Thick Film Interference.

    ERIC Educational Resources Information Center

    Trefil, James

    1983-01-01

    Discusses why interference effects cannot be seen with a thick film, starting with a review of the origin of interference patterns in thin films. Considers properties of materials in films, properties of the light source, and the nature of light. (JN)

  15. MODELING TRANSFER OF LISTRIA MONOCYTOGENES BETWEEN MEAT SLICER AND HAM DURING SLICING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes has been implicated in several listeriosis outbreaks linked to the consumption of pre-sliced ready-to-eat (RTE) deli meats. The possible contamination of sliced RTE meats by L. monocytogenes during the slicing process has become a public health concern. The objectives of thi...

  16. Beef Longissimus Slice Shear Force Measurement Among Steak Locations and Institutions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were 1) to evaluate slice shear force on every longissimus thoracis et lumborum steak to determine which steaks were appropriate for slice shear force measurement and 2) to train six other institutions to conduct slice shear force and then determine the among and within ...

  17. Modeling Transfer of Listeria monocytogenes on Deli Meat During Mechanical Slicing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes has been implicated in several listeriosis outbreaks linked to the consumption of pre-sliced ready-to-eat (RTE) deli meats. The possible contamination of sliced RTE meats by L. monocytogenes during the slicing process has become a public health concern. The objectives of thi...

  18. Current economic and sensitivity analysis for ID slicing of 4 inch and 6 inch diameter silicon ingots for photovoltaic applications

    NASA Technical Reports Server (NTRS)

    Roberts, E. G.; Johnson, C. M.

    1982-01-01

    The economics and sensitivities of slicing large diameter silicon ingots for photovoltaic applications were examined. Current economics and slicing add on cost sensitivities are calculated using variable parameters for blade life, slicing yield, and slice cutting speed. It is indicated that cutting speed has the biggest impact on slicing add on cost, followed by slicing yield, and by blade life as the blade life increases.

  19. Changes in Bladder Wall Thickness and Detrusor Wall Thickness After Surgical Treatment of Benign Prostatic Enlargement in Patients With Lower Urinary Tract Symptoms: A Preliminary Report

    PubMed Central

    Lee, Hakmin; Choo, Minsoo; Kim, Myong; Cho, Sung Yong; Lee, Seung Bae; Jeong, Hyeon

    2014-01-01

    Purpose The purpose of the present study was to evaluate the perioperative changes in bladder wall thickness and detrusor wall thickness after transurethral prostatectomy. Materials and Methods Fifty-one men who were treated for benign prostatic hyperplasia/lower urinary tract symptoms with transurethral prostatectomy were prospectively analyzed from May 2012 to July 2013. Prostate size, detrusor wall thickness, and bladder wall thickness were assessed by transrectal and transabdominal ultrasonography perioperatively. All postoperative evaluations were performed 1 month after the surgery. Results The patients' mean age was 69.0 years, the mean prostate-specific antigen concentration was 8.1 ng/mL, and the mean prostate volume was 63.2 mL. The mean bladder wall thickness was 5.1 mm (standard deviation [SD], ±1.6), 5.1 mm (SD, ±1.6), and 5.0 mm (SD, ±1.4) preoperatively and 4.5 mm (SD, ±1.5), 4.5 mm (SD, ±1.3), and 4.6 mm (SD, ±1.2) postoperatively in the anterior wall, dome, and trigone, respectively (p=0.178, p=0.086, and p=0.339, respectively). The mean detrusor wall thickness was 0.9 mm (SD, ±0.4) preoperatively and 0.7 mm (SD, ±0.3) postoperatively (p=0.001). A subgroup analysis stratifying patients into a large prostate group (weight, ≥45 g) and a high Abrams-Griffiths number group (>30) showed a significant decrease in detrusor wall thickness (p=0.002, p=0.018). Conclusions There was a decrease in detrusor wall thickness after transurethral prostatectomy. The large prostate group and the high Abrams-Griffiths number group showed a significant decrease in detrusor wall thickness after surgery. PMID:24466397

  20. Alternative oxidase expression in aged potato tuber slices

    SciTech Connect

    Hiser, C.; Herdies, L.; McIntosh, L. )

    1989-04-01

    Higher plant mitochondria posses a cyanide-resistant, hydroxamate-sensitive alternative pathway of electron transport that does not conserve energy. Aging of potato tuber slices for 24 hours leads to the development of an alternative pathway capacity. We have shown that a monoclonal antibody raised against the alternative pathway terminal oxidase of Sauromatum guttatum crossreacts with a protein of similar size in aged potato slice mitochondria. This protein was partially purified and characterized by two-dimensional gel electrophoresis, and its relative levels parallel the rise in cyanide-resistant respiration. We are using a putative clone of the S. guttatum alternative oxidase gene to isolate the equivalent gene from potato and to examine its expression.

  1. ERTS-1 image enhancement by optically combining density slices

    NASA Technical Reports Server (NTRS)

    Tapper, G. O.; Pease, R. W.

    1973-01-01

    The technique of density slicing using a photographic film and its application to enhancement of ERTS-1 imagery has proved to be useful for mapping varigated areal phenomena and provides a useful supplement ot the I2S MiniAddcol viewing system. The intial experiments conducted with this film were encouraging, and indicated that this technique of density slicing using readily accessible darkroom facilities and simple darkroom procedures allows rapid, accurate, and facile interpretation of certain areal phenomena to be made from the imagery. The distribution of the tree yucca, Yucca brevifolia Jaegeriana, in the eastern Mojave Desert of Southern California and southern Nevada was used as an example to test the accuracy of the technique for mapping purposes. The distribution was mapped at a relatively high level of accuracy.

  2. Comparison of 2- and 3-Phase Bearingless Slice Motor Concepts

    NASA Astrophysics Data System (ADS)

    Zürcher, Franz; Nussbaumer, Thomas; Gruber, Wolfgang; Kolar, Johann W.

    Several processes in chemical, pharmaceutical, biotechnology and semiconductor industry require contactless levitation and rotation through a hermetically closed process chamber. A highly interesting topology for these applications is the “bearingless slice motor” concept, where already some research has been done in the past, especially focusing on topology and implementation issues. However, only little work has been done to evaluate the ideal number of motor phases. In this paper, a performance evaluation between 2-phase and 3-phase bearingless slice motor concepts is undertaken. It is shown, that 3-phase systems can supply almost the same power as state-of-the-art 2-phase systems and achieve nearly the same acceleration behavior, although they have significantly less power electronics effort.

  3. Authentication and self-correction in sequential MRI slices.

    PubMed

    Fotopoulos, Vassilis; Stavrinou, Maria L; Skodras, Athanassios N

    2011-10-01

    One of the new challenges of Information Technology in the medical world is the protection and authentication of a variety of digital medical files, datasets, and images. In this work, the ability of magnetic resonance imaging (MRI) slice sequences to hide digital data is investigated and more specifically the case that the hidden data are the regions of interest (ROI) of the MRI slices. The regions of non-interest (RONI) are used as cover. The hiding capacity of the whole sequence is taken into account. Any ROI-targeted tampering attempt can be detected, and the original image can be self-restored (under certain conditions) by extracting the ROI from the RONI. PMID:20945077

  4. Analysis of the halo background in femtosecond slicing experiments.

    PubMed

    Schick, Daniel; Le Guyader, Loïc; Pontius, Niko; Radu, Ilie; Kachel, Torsten; Mitzner, Rolf; Zeschke, Thomas; Schüßler-Langeheine, Christian; Föhlisch, Alexander; Holldack, Karsten

    2016-05-01

    The slicing facility FemtoSpeX at BESSY II offers unique opportunities to study photo-induced dynamics on femtosecond time scales by means of X-ray magnetic circular dichroism, resonant and non-resonant X-ray diffraction, and X-ray absorption spectroscopy experiments in the soft X-ray regime. Besides femtosecond X-ray pulses, slicing sources inherently also produce a so-called `halo' background with a different time structure, polarization and pointing. Here a detailed experimental characterization of the halo radiation is presented, and a method is demonstrated for its correct and unambiguous removal from femtosecond time-resolved data using a special laser triggering scheme as well as analytical models. Examples are given for time-resolved measurements with corresponding halo correction, and errors of the relevant physical quantities caused by either neglecting or by applying a simplified model to describe this background are estimated. PMID:27140149

  5. Ion Beam Slicing of Single Crystal Oxide Thin Films

    SciTech Connect

    Thevuthasan, Suntharampillai; Shutthanandan, V; Jiang, Weilin; Weber, William J.; DB Poker, SC Moss, K-H Heinig

    2001-04-25

    Epitaxial thin film liftoff using the ion-slicing method has been applied to SrTiO single crystals. Rutherford backscattering spectrometry along with channeling (RBS/C) has been used to investigate the relative disorder as a function of temperature from the samples that were irradiated by 40 KeV hydrogen ions to a fluence of 5.0x10 16 H/cm. Hydrogen profiles were also measured as a function of annealing temperature to understand the role of hydrogen in the ion slicing process. Film cleavage occurred during or after annealing at 570 K, and cleaved film has been successfully transferred to a silicon substrate using ceramic adhesive.

  6. Controlled Dense Coding Using the Maximal Slice States

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Mo, Zhi-wen; Sun, Shu-qin

    2016-04-01

    In this paper we investigate the controlled dense coding with the maximal slice states. Three schemes are presented. Our schemes employ the maximal slice states as quantum channel, which consists of the tripartite entangled state from the first party(Alice), the second party(Bob), the third party(Cliff). The supervisor(Cliff) can supervises and controls the channel between Alice and Bob via measurement. Through carrying out local von Neumann measurement, controlled-NOT operation and positive operator-valued measure(POVM), and introducing an auxiliary particle, we can obtain the success probability of dense coding. It is shown that the success probability of information transmitted from Alice to Bob is usually less than one. The average amount of information for each scheme is calculated in detail. These results offer deeper insight into quantum dense coding via quantum channels of partially entangled states.

  7. Measurement of compressed breast thickness by optical stereoscopic photogrammetry

    SciTech Connect

    Tyson, Albert H.; Mawdsley, Gordon E.; Yaffe, Martin J.

    2009-02-15

    The determination of volumetric breast density (VBD) from mammograms requires accurate knowledge of the thickness of the compressed breast. In attempting to accurately determine VBD from images obtained on conventional mammography systems, the authors found that the thickness reported by a number of mammography systems in the field varied by as much as 15 mm when compressing the same breast or phantom. In order to evaluate the behavior of mammographic compression systems and to be able to predict the thickness at different locations in the breast on patients, they have developed a method for measuring the local thickness of the breast at all points of contact with the compression paddle using optical stereoscopic photogrammetry. On both flat (solid) and compressible phantoms, the measurements were accurate to better than 1 mm with a precision of 0.2 mm. In a pilot study, this method was used to measure thickness on 108 volunteers who were undergoing mammography examination. This measurement tool will allow us to characterize paddle surface deformations, deflections and calibration offsets for mammographic units.

  8. Thick film ink chemistry

    NASA Astrophysics Data System (ADS)

    Gehman, R. W.

    1982-03-01

    Twenty-six thick film inks from two vendors were proved for hybrid microcircuit production use. A data base of chemical information was established for all the inks to aid in future diagnostic and failure analysis activities. Efforts included both organic chemical analysis of printing vehicles and binders and inorganic chemical analysis of glass frits and electrically active phases. Analytical methods included infrared spectroscopy, mass spectroscopy, gas chromatography, X-ray fluorescence, emission spectroscopy, atomic absorption spectroscopy, and wet chemical techniques.

  9. Astronomy in the region between 1 mm and 0.1 mm wavelength

    NASA Technical Reports Server (NTRS)

    Weiss, Rainer; Meyer, Stephan S.

    1994-01-01

    The research under this grant resulted in the measurement of anisotropy of the Cosmic Microwave Background Radiation (CMBR) on angular scales from 90 degrees to 0.3 degrees. A bolometric radiometer was built with a sensitivity of better than 500 micro K divided by the square root of (Hz). The measurements complement the COBE anisotropy measurement in two ways. The large scale measurements were shown to cross-correlate with the COBE DMR anisotropy detection, confirming the results. The small scale measurements further the understanding of the structure in the CMBR on scales where we can begin to model the early stages in galaxy and galaxy cluster formation.

  10. A recording chamber for small volume slice electrophysiology.

    PubMed

    Dondzillo, Anna; Quinn, Kevin D; Cruickshank-Quinn, Charmion I; Reisdorph, Nichole; Lei, Tim C; Klug, Achim

    2015-09-01

    Electrophysiological recordings from brain slices are typically performed in small recording chambers that allow for the superfusion of the tissue with artificial extracellular solution (ECS), while the chamber holding the tissue is mounted in the optical path of a microscope to image neurons in the tissue. ECS itself is inexpensive, and thus superfusion rates and volumes of ECS consumed during an experiment using standard ECS are not critical. However, some experiments require the addition of expensive pharmacological agents or other chemical compounds to the ECS, creating a need to build superfusion systems that operate on small volumes while still delivering appropriate amounts of oxygen and other nutrients to the tissue. We developed a closed circulation tissue chamber for slice recordings that operates with small volumes of bath solution in the range of 1.0 to 2.6 ml and a constant oxygen/carbon dioxide delivery to the solution in the bath. In our chamber, the ECS is oxygenated and recirculated directly in the recording chamber, eliminating the need for tubes and external bottles/containers to recirculate and bubble ECS and greatly reducing the total ECS volume required for superfusion. At the same time, the efficiency of tissue oxygenation and health of the section are comparable to standard superfusion methods. We also determined that the small volume of ECS contains a sufficient amount of nutrients to support the health of a standard brain slice for several hours without concern for either depletion of nutrients or accumulation of waste products. PMID:26203105

  11. Organotypic Slice Cultures to Study Oligodendrocyte Dynamics and Myelination

    PubMed Central

    Hill, Robert A.; Medved, Jelena; Patel, Kiran D.; Nishiyama, Akiko

    2014-01-01

    NG2 expressing cells (polydendrocytes, oligodendrocyte precursor cells) are the fourth major glial cell population in the central nervous system. During embryonic and postnatal development they actively proliferate and generate myelinating oligodendrocytes. These cells have commonly been studied in primary dissociated cultures, neuron cocultures, and in fixed tissue. Using newly available transgenic mouse lines slice culture systems can be used to investigate proliferation and differentiation of oligodendrocyte lineage cells in both gray and white matter regions of the forebrain and cerebellum. Slice cultures are prepared from early postnatal mice and are kept in culture for up to 1 month. These slices can be imaged multiple times over the culture period to investigate cellular behavior and interactions. This method allows visualization of NG2 cell division and the steps leading to oligodendrocyte differentiation while enabling detailed analysis of region-dependent NG2 cell and oligodendrocyte functional heterogeneity. This is a powerful technique that can be used to investigate the intrinsic and extrinsic signals influencing these cells over time in a cellular environment that closely resembles that found in vivo. PMID:25177825

  12. Slice imaging of photodissociation of spatially oriented molecules

    SciTech Connect

    Lipciuc, M. Laura; Brom, Alrik J. van den; Dinu, Laura; Janssen, Maurice H.M.

    2005-12-15

    An electrostatic ion lens to spatially orient parent molecules and to image the angular distribution of photofragments is presented. Photodissociation of laboratory-oriented molecules makes it possible to study the dynamics of the dissociation process in more detail compared to photodissociation of nonoriented molecules. Using the velocity map imaging technique in combination with the slice imaging technique, the spatial recoil distribution of the photofragments can be measured with high resolution and without symmetry restrictions. Insertion of orientation electrodes between the repeller and the extractor of a velocity mapping electrostatic lens severely distorts the ion trajectories. The position where the ions are focused by the lens, the focal length, can be very different in the directions parallel and perpendicular to the inserted orientation electrodes. The focal length depends on the exact dimensions and positions of the electrodes of the ion lens. As this dependence is different in both directions, this dependence can be used to correct for the distorted ion trajectories. We discuss the design of an electrostatic ion lens, which is able to orient parent molecules and map the velocity of the photofragments. We report sliced images of photofragments from photolysis of spatially oriented CD{sub 3}I molecules to demonstrate the experimental combination of molecular orientation and velocity map slice imaging with good resolution.

  13. Stable Isotope Resolved Metabolomics Studies in Ex Vivo TIssue Slices

    PubMed Central

    Fan, Teresa W-M.; Lane, Andrew N.; Higashi, Richard M.

    2016-01-01

    An important component of this methodology is to assess the role of the tumor microenvironment on tumor growth and survival. To tackle this problem, we have adapted the original approach of Warburg 1, by combining thin tissue slices with Stable Isotope Resolved Metabolomics (SIRM) to determine detailed metabolic activity of human tissues. SIRM enables the tracing of metabolic transformations of source molecules such as glucose or glutamine over defined time periods, and is a requirement for detailed pathway tracing and flux analysis. In our approach, we maintain freshly resected tissue slices (both cancerous and non- cancerous from the same organ of the same subject) in cell culture media, and treat with appropriate stable isotope-enriched nutrients, e.g. 13C6-glucose or 13C5, 15N2 -glutamine. These slices are viable for at least 24 h, and make it possible to eliminate systemic influence on the target tissue metabolism while maintaining the original 3D cellular architecture. It is therefore an excellent pre-clinical platform for assessing the effect of therapeutic agents on target tissue metabolism and their therapeutic efficacy on individual patients 2,3. PMID:27158639

  14. Energetics of low affinity amino acid transport into brain slices.

    PubMed

    Banay-Schwartz, M; Teller, D N; Lajtha, A

    1976-01-01

    It appears possible to dissect and study some of the potential energy sources for amino acid transport in brain slices despite the apparent complexity of the tissue in comparison to that of isolated bacterial vesicles23. The uptake capability of the tissue may be inadvertently damaged in some experimental protocols so that very special controls must be used to ensure that the treatment did not somehow inactivate the very mechanism that thereafter will be tested. We have presented some evidence that brain slice amino acid transport may not be obligatorily linked to glycolysis, ATP levels, Na+, K+-ATPase activity, K+ levels or direction of flux, or to Na+ flux. However, the energy source linkage for different amino acids appears to be rather specific, so that further generalizations are difficult to sustain. For instance, the incubation media and conditions we describe here were experimentally adjusted to maximize uptake of D-glu or alpha-AIB in the absence of glucose, or in lowered K+ or Na+. Therefore, these procedures, the results of which directly challenge some common assumptions regarding the energy basis for active transport in brain slices, probably will not be universally extensible to all other actively transported amino acids. PMID:782193

  15. Model-based cartilage thickness measurement in the submillimeter range

    SciTech Connect

    Streekstra, G. J.; Strackee, S. D.; Maas, M.; Wee, R. ter; Venema, H. W.

    2007-09-15

    Current methods of image-based thickness measurement in thin sheet structures utilize second derivative zero crossings to locate the layer boundaries. It is generally acknowledged that the nonzero width of the point spread function (PSF) limits the accuracy of this measurement procedure. We propose a model-based method that strongly reduces PSF-induced bias by incorporating the PSF into the thickness estimation method. We estimated the bias in thickness measurements in simulated thin sheet images as obtained from second derivative zero crossings. To gain insight into the range of sheet thickness where our method is expected to yield improved results, sheet thickness was varied between 0.15 and 1.2 mm with an assumed PSF as present in the high-resolution modes of current computed tomography (CT) scanners [full width at half maximum (FWHM) 0.5-0.8 mm]. Our model-based method was evaluated in practice by measuring layer thickness from CT images of a phantom mimicking two parallel cartilage layers in an arthrography procedure. CT arthrography images of cadaver wrists were also evaluated, and thickness estimates were compared to those obtained from high-resolution anatomical sections that served as a reference. The thickness estimates from the simulated images reveal that the method based on second derivative zero crossings shows considerable bias for layers in the submillimeter range. This bias is negligible for sheet thickness larger than 1 mm, where the size of the sheet is more than twice the FWHM of the PSF but can be as large as 0.2 mm for a 0.5 mm sheet. The results of the phantom experiments show that the bias is effectively reduced by our method. The deviations from the true thickness, due to random fluctuations induced by quantum noise in the CT images, are of the order of 3% for a standard wrist imaging protocol. In the wrist the submillimeter thickness estimates from the CT arthrography images correspond within 10% to those estimated from the anatomical

  16. Calculation of water equivalent thickness of materials of arbitrary density, elemental composition and thickness in proton beam irradiation.

    PubMed

    Zhang, Rui; Newhauser, Wayne D

    2009-03-21

    In proton therapy, the radiological thickness of a material is commonly expressed in terms of water equivalent thickness (WET) or water equivalent ratio (WER). However, the WET calculations required either iterative numerical methods or approximate methods of unknown accuracy. The objective of this study was to develop a simple deterministic formula to calculate WET values with an accuracy of 1 mm for materials commonly used in proton radiation therapy. Several alternative formulas were derived in which the energy loss was calculated based on the Bragg-Kleeman rule (BK), the Bethe-Bloch equation (BB) or an empirical version of the Bethe-Bloch equation (EBB). Alternative approaches were developed for targets that were 'radiologically thin' or 'thick'. The accuracy of these methods was assessed by comparison to values from an iterative numerical method that utilized evaluated stopping power tables. In addition, we also tested the approximate formula given in the International Atomic Energy Agency's dosimetry code of practice (Technical Report Series No 398, 2000, IAEA, Vienna) and stopping power ratio approximation. The results of these comparisons revealed that most methods were accurate for cases involving thin or low-Z targets. However, only the thick-target formulas provided accurate WET values for targets that were radiologically thick and contained high-Z material. PMID:19218739

  17. Calculation of water equivalent thickness of materials of arbitrary density, elemental composition and thickness in proton beam irradiation

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Newhauser, Wayne D.

    2009-03-01

    In proton therapy, the radiological thickness of a material is commonly expressed in terms of water equivalent thickness (WET) or water equivalent ratio (WER). However, the WET calculations required either iterative numerical methods or approximate methods of unknown accuracy. The objective of this study was to develop a simple deterministic formula to calculate WET values with an accuracy of 1 mm for materials commonly used in proton radiation therapy. Several alternative formulas were derived in which the energy loss was calculated based on the Bragg-Kleeman rule (BK), the Bethe-Bloch equation (BB) or an empirical version of the Bethe-Bloch equation (EBB). Alternative approaches were developed for targets that were 'radiologically thin' or 'thick'. The accuracy of these methods was assessed by comparison to values from an iterative numerical method that utilized evaluated stopping power tables. In addition, we also tested the approximate formula given in the International Atomic Energy Agency's dosimetry code of practice (Technical Report Series No 398, 2000, IAEA, Vienna) and stopping power ratio approximation. The results of these comparisons revealed that most methods were accurate for cases involving thin or low-Z targets. However, only the thick-target formulas provided accurate WET values for targets that were radiologically thick and contained high-Z material.

  18. Evaluation of Palatal Plate Thickness of Maxillary Prosthesis on Phonation- A Comparative Clinical Study

    PubMed Central

    B, Sreedevi; Anne, Gopinadh; Manne, Prakash; Bindu O, Swetha Hima; Atla, Jyothi; Deepthi, Sneha; Chaitanya A, Krishna

    2014-01-01

    Background: Prosthodontic treatment involves clinical procedures which influence speech performance directly or indirectly. Prosthetic rehabilitation of missing teeth with partial or complete maxillary removable dentures influences the individual voice characteristics like Phonation, resonance etc. Aim: To evaluate the effect of Acrylic palatal plate thickness (1mm-3mm) of maxillary prosthesis on phonation. Materials and Methods: Twelve subjects were selected randomly between the age group of 20-25 years who have full complement of teeth and have no speech problems. Speech evaluation was done under four experimental conditions i.e. Without any experimental acrylic palatal plate (control), with experimental acrylic palatal plates of thickness 1 mm, 2 mm and 3 mm respectively. The speech material for phonation test consisted of Vowels sounds /a/, /i/, and /o/. Speech analysis to assess phonation was done using digital acoustic analysis (PRAAT software). The obtained results were statistically analyzed by One-way ANOVA and Tukey’s multiple post-hoc for comparison of four experimental conditions with respect to different vowel sounds. Results: Mean harmonics to noise ratio (HNR) values obtained for all the Experimental conditions did not show significant difference (p>0.05). In conclusion, an increase in the thickness of the acrylic palatal plate of maxillary prosthesis for about 1 mm - 3mm in complete or partial maxillary removable dentures resulted in no significant effect on phonation of vowel sounds /a/, /i/ and /o/. Conclusion: Increasing the thickness of the palatal plate from 1 mm to 3 mm has not shown any significant effect on the phonation. PMID:24959508

  19. Fingolimod Attenuates Splenocyte-Induced Demyelination in Cerebellar Slice Cultures

    PubMed Central

    Pritchard, Adam J.; Mir, Anis K.; Dev, Kumlesh K.

    2014-01-01

    The family of sphingosine-1-phosphate receptors (S1PRs) is G-protein-coupled, comprised of subtypes S1PR1-S1PR5 and activated by the endogenous ligand S1P. The phosphorylated version of Fingolimod (pFTY720), an oral therapy for multiple sclerosis (MS), induces S1PR1 internalisation in T cells, subsequent insensitivity to S1P gradients and sequestering of these cells within lymphoid organs, thus limiting immune response. S1PRs are also expressed in neuronal and glial cells where pFTY720 is suggested to directly protect against lysolecithin-induced deficits in myelination state in organotypic cerebellar slices. Of note, the effect of pFTY720 on immune cells already migrated into the CNS, prior to treatment, has not been well established. We have previously found that organotypic slice cultures do contain immune cells, which, in principle, could also be regulated by pFTY720 to maintain levels of myelin. Here, a mouse organotypic cerebellar slice and splenocyte co-culture model was thus used to investigate the effects of pFTY720 on splenocyte-induced demyelination. Spleen cells isolated from myelin oligodendrocyte glycoprotein immunised mice (MOG-splenocytes) or from 2D2 transgenic mice (2D2-splenocytes) both induced demyelination when co-cultured with mouse organotypic cerebellar slices, to a similar extent as lysolecithin. As expected, in vivo treatment of MOG-immunised mice with FTY720 inhibited demyelination induced by MOG-splenocytes. Importantly, in vitro treatment of MOG- and 2D2-splenocytes with pFTY720 also attenuated demyelination caused by these cells. In addition, while in vitro treatment of 2D2-splenocytes with pFTY720 did not alter cell phenotype, pFTY720 inhibited the release of the pro-inflammatory cytokines such as interferon gamma (IFNγ) and interleukin 6 (IL6) from these cells. This work suggests that treatment of splenocytes by pFTY720 attenuates demyelination and reduces pro-inflammatory cytokine release, which likely contributes to enhanced

  20. The topology of large-scale structure. VI - Slices of the universe

    NASA Technical Reports Server (NTRS)

    Park, Changbom; Gott, J. R., III; Melott, Adrian L.; Karachentsev, I. D.

    1992-01-01

    Results of an investigation of the topology of large-scale structure in two observed slices of the universe are presented. Both slices pass through the Coma cluster and their depths are 100 and 230/h Mpc. The present topology study shows that the largest void in the CfA slice is divided into two smaller voids by a statistically significant line of galaxies. The topology of toy models like the white noise and bubble models is shown to be inconsistent with that of the observed slices. A large N-body simulation was made of the biased cloud dark matter model and the slices are simulated by matching them in selection functions and boundary conditions. The genus curves for these simulated slices are spongelike and have a small shift in the direction of a meatball topology like those of observed slices.

  1. Temperature effects on evoked potentials of hippocampal slices from euthermic chipmunks, hamsters and rats

    NASA Technical Reports Server (NTRS)

    Hooper, D. C.; Martin, S. M.; Horowitz, J. M.

    1985-01-01

    1. Neural activity was recorded in hippocampal slices from euthermic chipmunks, hamsters and rats. 2. While recording the evoked potentials, the temperature of the Ringer's solution bathing the slice was varied by controlling the temperature of an outer chamber jacketing the recording chamber. 3. The temperature just below that at which a population spike could be evoked, Tt, was 10.4 +/- 0.3 degrees C (mean +/- SEM) for chipmunk slices, 14.1 +/- 0.4 degrees C for rat slices and 14.8 +/- 0.4 degrees C for hamster slices. Tt was significantly lower in the chipmunk slices (P<0.01) than in the rat and hamster slices. 4. Data were interpreted as consistent with the hypothesis that chipmunk hippocampal neurons are intrinsically cold resistant.

  2. Effects of temperature and bias voltage on the properties of a PET detector module based on the individual readout of 1 × 1 mm2 LYSO crystals by monolithic arrays of SiPMs

    NASA Astrophysics Data System (ADS)

    Fürst, S.; Pulko, J.; Hohberg, M.; Mann, A. B.; Ziegler, S. I.

    2012-08-01

    The aim of this work was the development and evaluation of a detector based on SiPMs and fast scintillation crystals feasible for combined PET and MR imaging. Properties of two different 4 × 4 arrays of SiPMs by Hamamatsu — breakdown voltage, pulse height, energy resolution, dark counts and optical crosstalk — were investigated in terms of temperature and voltage dependence. Each channel in such an array consists of either 400 or 1600 cells and has a surface area of 1 × 1 mm2. For the alignment and coupling of individual scintillation crystals (1 × 1 × 20 mm3) to these channels a special holder was designed. The breakdown voltages were at about 70 V for both models. Energy resolutions better than 23 % were observed. A temperature coefficient of the signal amplitude of (-2.7 ± 0.2) %/K and a voltage coefficient of (63 ± 2) %/V were determined for the model with 400 cells, whereas optical crosstalk was found to be an issue that needs further improvement. The dark count rate was below 1 MHz.

  3. Fetal nuchal translucency thickness.

    PubMed

    Witters, I; Fryns, J R

    2007-01-01

    In the early 1990s Nicolaides introduced screening for trisomy 21 by fetal nuchal translucency thickness measurement with ultrasound between 11-13(+6) weeks. Already in 1866 L. Down noted that common features of patients with trisomy 21 are a skin being too large for the body and a flat face with a small nose. While detection rates for trisomy 21, given an invasive testing rate of 5%, were only 30% for screening by maternal age and 65% for screening by maternal serum triple test, the detection rate for screening by nuchal translucency combined with maternal age was 75% and this could be increased to 90% in combination with maternal serum screening (serum B-human chorionic gonadotropin and pregnancy-associated plasma protein-A) at 11-13(+6) weeks. The additional soft markers in the first trimester are the fetal nasal bone, the Doppler velocity waveform in the ductus venosus and tricuspid regurgitation and these markers can be used to further increase the detection rate of trisomy 21. In addition increased nuchal translucency thickness can also identify other chromosomal defects (mainly trisomy 13 and 18 and monosomy X) and major congenital malformations (mainly cardiac defects) and genetic syndromes. PMID:17515296

  4. Investigation of lung nodule detectability in low-dose 320-slice computed tomography

    PubMed Central

    Silverman, J. D.; Paul, N. S.; Siewerdsen, J. H.

    2009-01-01

    Low-dose imaging protocols in chest CT are important in the screening and surveillance of suspicious and indeterminate lung nodules. Techniques that maintain nodule detectability yet permit dose reduction, particularly for large body habitus, were investigated. The objective of this study was to determine the extent to which radiation dose can be minimized while maintaining diagnostic performance through knowledgeable selection of reconstruction techniques. A 320-slice volumetric CT scanner (Aquilion ONE™, Toshiba Medical Systems) was used to scan an anthropomorphic phantom at doses ranging from ∼0.1 mGy up to that typical of low-dose CT (LDCT, ∼5 mGy) and diagnostic CT (∼10 mGy). Radiation dose was measured via Farmer chamber and MOSFET dosimetry. The phantom presented simulated nodules of varying size and contrast within a heterogeneous background, and chest thickness was varied through addition of tissue-equivalent bolus about the chest. Detectability of a small solid lung nodule (3.2 mm diameter, −37 HU, typically the smallest nodule of clinical significance in screening and surveillance) was evaluated as a function of dose, patient size, reconstruction filter, and slice thickness by means of nine-alternative forced-choice (9AFC) observer tests to quantify nodule detectability. For a given reconstruction filter, nodule detectability decreased sharply below a threshold dose level due to increased image noise, especially for large body size. However, nodule detectability could be maintained at lower doses through knowledgeable selection of (smoother) reconstruction filters. For large body habitus, optimal filter selection reduced the dose required for nodule detection by up to a factor of ∼3 (from ∼3.3 mGy for sharp filters to ∼1.0 mGy for the optimal filter). The results indicate that radiation dose can be reduced below the current low-dose (5 mGy) and ultralow-dose (1 mGy) levels with knowledgeable selection of reconstruction parameters. Image

  5. Whole-cell Patch-clamp Recordings in Brain Slices.

    PubMed

    Segev, Amir; Garcia-Oscos, Francisco; Kourrich, Saïd

    2016-01-01

    Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the electrical properties of a substantial part of the neuron. In this configuration, the micropipette is in tight contact with the cell membrane, which prevents current leakage and thereby provides more accurate ionic current measurements than the previously used intracellular sharp electrode recording method. Classically, whole-cell recording can be performed on neurons in various types of preparations, including cell culture models, dissociated neurons, neurons in brain slices, and in intact anesthetized or awake animals. In summary, this technique has immensely contributed to the understanding of passive and active biophysical properties of excitable cells. A major advantage of this technique is that it provides information on how specific manipulations (e.g., pharmacological, experimenter-induced plasticity) may alter specific neuronal functions or channels in real-time. Additionally, significant opening of the plasma membrane allows the internal pipette solution to freely diffuse into the cytoplasm, providing means for introducing drugs, e.g., agonists or antagonists of specific intracellular proteins, and manipulating these targets without altering their functions in neighboring cells. This article will focus on whole-cell recording performed on neurons in brain slices, a preparation that has the advantage of recording neurons in relatively well preserved brain circuits, i.e., in a physiologically relevant context. In particular, when combined with appropriate pharmacology, this technique is a powerful tool allowing identification of specific neuroadaptations that occurred following any type of experiences, such as learning, exposure to drugs of abuse, and stress. In summary, whole-cell patch-clamp recordings in brain slices provide means to measure in ex vivo preparation long-lasting changes in neuronal functions that have developed in intact awake animals

  6. Improved sliced velocity map imaging apparatus optimized for H photofragments.

    PubMed

    Ryazanov, Mikhail; Reisler, Hanna

    2013-04-14

    Time-sliced velocity map imaging (SVMI), a high-resolution method for measuring kinetic energy distributions of products in scattering and photodissociation reactions, is challenging to implement for atomic hydrogen products. We describe an ion optics design aimed at achieving SVMI of H fragments in a broad range of kinetic energies (KE), from a fraction of an electronvolt to a few electronvolts. In order to enable consistently thin slicing for any imaged KE range, an additional electrostatic lens is introduced in the drift region for radial magnification control without affecting temporal stretching of the ion cloud. Time slices of ∼5 ns out of a cloud stretched to ⩾50 ns are used. An accelerator region with variable dimensions (using multiple electrodes) is employed for better optimization of radial and temporal space focusing characteristics at each magnification level. The implemented system was successfully tested by recording images of H fragments from the photodissociation of HBr, H2S, and the CH2OH radical, with kinetic energies ranging from <0.4 eV to >3 eV. It demonstrated KE resolution ≲1%-2%, similar to that obtained in traditional velocity map imaging followed by reconstruction, and to KE resolution achieved previously in SVMI of heavier products. We expect it to perform just as well up to at least 6 eV of kinetic energy. The tests showed that numerical simulations of the electric fields and ion trajectories in the system, used for optimization of the design and operating parameters, provide an accurate and reliable description of all aspects of system performance. This offers the advantage of selecting the best operating conditions in each measurement without the need for additional calibration experiments. PMID:24981528

  7. Inhibition of intermediary metabolism by amiodarone in dog thyroid slices

    SciTech Connect

    Pasquali, D.; Tseng, F.Y.; Rani, C.S.; Field, J.B. )

    1990-10-01

    Amiodarone, an iodine-containing antiarrhythmic drug, has been reported to interfere with thyroid function and thyroid hormone metabolism. We studied the effects of amiodarone on basal and agonist (thyroid-stimulating hormone (TSH), phorbol ester, or carbachol)-stimulated glucose oxidation, 32PO4 incorporation into phospholipids, and adenosine 3',5'-cyclic monophosphate (cAMP) concentration in dog thyroid slices. Slices were preincubated with amiodarone at 37 degrees C for 1 h before the addition of agonist and the appropriate radioisotope. cAMP stimulation was measured after 20 min, glucose oxidation for 45 min, and 32PO4 incorporation into phospholipids for 2 h. Amiodarone (0.5 mM) had no effect on basal 14CO2 formation or 32PO4 incorporation into phospholipids but significantly inhibited TSH, phorbol ester, and carbachol stimulation of these parameters. It also inhibited cAMP stimulation by TSH. Inhibition of TSH-stimulated (14C)glucose oxidation was also obtained with another iodide-containing compound, iopanoic acid (0.5 mM), but not with iothalamate (up to 10 mM). Inhibition by amiodarone was still present, but to a lesser extent, when it was added at the same time as the agonist. Inhibition of stimulated (14C)glucose oxidation persisted even after the slices were incubated without amiodarone for 6 h. Inhibition by amiodarone, in contrast to that by inorganic iodide, was not prevented by 1 mM methimazole added at the same time as amiodarone. These results indicate that the inhibitory effects of amiodarone on thyroid function are not due to dissociation of iodide from the molecule.

  8. Improved sliced velocity map imaging apparatus optimized for H photofragments

    SciTech Connect

    Ryazanov, Mikhail; Reisler, Hanna

    2013-04-14

    Time-sliced velocity map imaging (SVMI), a high-resolution method for measuring kinetic energy distributions of products in scattering and photodissociation reactions, is challenging to implement for atomic hydrogen products. We describe an ion optics design aimed at achieving SVMI of H fragments in a broad range of kinetic energies (KE), from a fraction of an electronvolt to a few electronvolts. In order to enable consistently thin slicing for any imaged KE range, an additional electrostatic lens is introduced in the drift region for radial magnification control without affecting temporal stretching of the ion cloud. Time slices of {approx}5 ns out of a cloud stretched to Greater-Than-Or-Slanted-Equal-To 50 ns are used. An accelerator region with variable dimensions (using multiple electrodes) is employed for better optimization of radial and temporal space focusing characteristics at each magnification level. The implemented system was successfully tested by recording images of H fragments from the photodissociation of HBr, H{sub 2}S, and the CH{sub 2}OH radical, with kinetic energies ranging from <0.4 eV to >3 eV. It demonstrated KE resolution Less-Than-Or-Equivalent-To 1%-2%, similar to that obtained in traditional velocity map imaging followed by reconstruction, and to KE resolution achieved previously in SVMI of heavier products. We expect it to perform just as well up to at least 6 eV of kinetic energy. The tests showed that numerical simulations of the electric fields and ion trajectories in the system, used for optimization of the design and operating parameters, provide an accurate and reliable description of all aspects of system performance. This offers the advantage of selecting the best operating conditions in each measurement without the need for additional calibration experiments.

  9. Ultrasonic Inspection Of Thick Sections

    NASA Technical Reports Server (NTRS)

    Friant, C. L.; Djordjevic, B. B.; O'Keefe, C. V.; Ferrell, W.; Klutz, T.

    1993-01-01

    Ultrasonics used to inspect large, relatively thick vessels for hidden defects. Report based on experiments in through-the-thickness transmission of ultrasonic waves in both steel and filament-wound composite cases of solid-fuel rocket motors.

  10. Spectral slicing X-ray telescope with variable magnification

    NASA Technical Reports Server (NTRS)

    Hoover, R. B.; Hildner, E. (Inventor)

    1985-01-01

    A telescope for viewing high frequency radiation (soft X-ray, extreme ultraviolet) is described. This telescope has a long focal length with a selection of magnifications despite a short housing. Light enters the telescope and is reflected by the telescope's primary optical system to one of several secondary mirrors at different locations on a movable frame. The secondary mirrors have varying degrees of magnification and select narrow spectral slices of the incident radiation. Thus, both the magnification and effective focal length field of view and wavelength can be altered by repositioning the moving frame. Configurations for spaceborne applications are discussed.

  11. Scatter imaging of injured brain slices: detection of mitochondrial injury

    NASA Astrophysics Data System (ADS)

    Johnson, Lee J.; Hanley, Daniel F.; Thakor, Nitish V.

    1999-06-01

    Stroke has been shown to cause exitotoxic injury, two of its manifestations being cellular and mitochondrial swelling. In vitro models of stroke attempt to reproduce the effects of stroke by treating brain tissue with excitotoxins or hypotonic solutions. To further resolve the mechanism of stroke injury, we have designed a dual-angle scatter imaging (DASI) system sensitive to particle size. The DASI system has been used with a hippocampal slice preparation to contrast cellular swelling, induced by hypotonicity, and combined cellular and mitochondrial swelling caused by excitotoxicity. We found that both hypotonic end excitotoxic treatments caused changes in light scatter. However, only excitotoxic treatment caused a significant change in DASI.

  12. Property of slice square polycapillary x-ray optics

    NASA Astrophysics Data System (ADS)

    Shi-Qi, Peng; Zhi-Guo, Liu; Tian-Xi, Sun; Kai, Wang; Long-Tao, Yi; Kui, Yang; Man, Chen; Jin-Bang, Wang

    2016-02-01

    A geometrical description of square polycapillary x-ray optics and the basic theory of the transmission of x-rays are presented. A method of numerical calculation is developed based on ray-tracing theory. The method simulates the intensity distribution of x-rays propagating through slice square polycapillary x-ray optics. The simulation results are compared with the experimental results. Project supported by the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2012LZD07 and 2014kJJCA03) and the National Natural Science Foundation of China (Grant Nos. 11375027 and 11075017).

  13. Calculation of water equivalent thickness of materials of arbitrary density, elemental composition and thickness in proton beam irradiation

    PubMed Central

    Zhang, Rui; Newhauser, Wayne D

    2014-01-01

    In proton therapy, the radiological thickness of a material is commonly expressed in terms of water equivalent thickness (WET) or water equivalent ratio (WER). However, the WET calculations required either iterative numerical methods or approximate methods of unknown accuracy. The objective of this study was to develop a simple deterministic formula to calculate WET values with an accuracy of 1 mm for materials commonly used in proton radiation therapy. Several alternative formulas were derived in which the energy loss was calculated based on the Bragg–Kleeman rule (BK), the Bethe–Bloch equation (BB) or an empirical version of the Bethe–Bloch equation (EBB). Alternative approaches were developed for targets that were ‘radiologically thin’ or ‘thick’. The accuracy of these methods was assessed by comparison to values from an iterative numerical method that utilized evaluated stopping power tables. In addition, we also tested the approximate formula given in the International Atomic Energy Agency's dosimetry code of practice (Technical Report Series No 398, 2000, IAEA, Vienna) and stopping power ratio approximation. The results of these comparisons revealed that most methods were accurate for cases involving thin or low-Z targets. However, only the thick-target formulas provided accurate WET values for targets that were radiologically thick and contained high-Z material. PMID:19218739

  14. Waterway Ice Thickness Measurements

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The ship on the opposite page is a U. S. Steel Corporation tanker cruising through the ice-covered waters of the Great Lakes in the dead of winter. The ship's crew is able to navigate safely by plotting courses through open water or thin ice, a technique made possible by a multi-agency technology demonstration program in which NASA is a leading participant. Traditionally, the Great Lakes-St. Lawrence Seaway System is closed to shipping for more than three months of winter season because of ice blockage, particularly fluctuations in the thickness and location of ice cover due to storms, wind, currents and variable temperatures. Shippers have long sought a system of navigation that would allow year-round operation on the Lakes and produce enormous economic and fuel conservation benefits. Interrupted operations require that industrial firms stockpile materials to carry them through the impassable months, which is costly. Alternatively, they must haul cargos by more expensive overland transportation. Studies estimate the economic benefits of year-round Great Lakes shipping in the hundreds of millions of dollars annually and fuel consumption savings in the tens of millions of gallons. Under Project Icewarn, NASA, the U.S. Coast Guard and the National Oceanic Atmospheric Administration collaborated in development and demonstration of a system that permits safe year-round operations. It employs airborne radars, satellite communications relay and facsimile transmission to provide shippers and ships' masters up-to-date ice charts. Lewis Research Center contributed an accurate methods of measuring ice thickness by means of a special "short-pulse" type of radar. In a three-year demonstration program, Coast Guard aircraft equipped with Side-Looking Airborne Radar (SLAR) flew over the Great Lakes three or four times a week. The SLAR, which can penetrate clouds, provided large area readings of the type and distribution of ice cover. The information was supplemented by short

  15. Optimization of taro mucilage and fat levels in sliced breads.

    PubMed

    Nagata, Carina Lumie Pereira; Andrade, Luan Alberto; Pereira, Joelma

    2015-09-01

    Bread is one of the most commonly consumed foods, and much ongoing research is aimed at meeting the demand for higher quality bread products in terms of greater volume and softness with characteristic flavor, aroma and color. The goal of the present study was to optimize the amounts of lyophilized taro mucilage and hydrogenated vegetable fat added to sliced bread formulations to improve the physical characteristics of the bread while reducing lipid levels and maintaining good sensorial quality. For the analysis, a central composite rotatable design (CCRD) was used for the two factors, resulting in 11 total experiments. Physical, chemical, and sensory analyses were performed. Breads containing taro mucilage were soft and exhibited good sensorial quality. Optimal amounts of the two factors studied were determined using response surface methodology to produce breads with greater specific volume, higher bread-making quality, and lower fat levels than current formulations. The optimal levels of lyophilized taro mucilage and hydrogenated vegetable fat in the sliced bread formulation were 0.73 g 100 g(-1) and 1.58 g 100 g(-1), respectively. PMID:26345005

  16. Electrophysiological recordings of patterned rat brain stem slice neurons.

    PubMed

    Lauer, L; Vogt, A; Yeung, C K; Knoll, W; Offenhäusser, A

    2002-08-01

    Dissociated neuronal cultures on substrates patterned with extracellular matrix (ECM) proteins have yielded much information in the past. However, although the culture of brain slices has many advantages over dissociated neuronal cultures, its feasibility on patterned substrates has not been demonstrated to date. In the present study, neuronal outgrowth from brain stem slices onto homogeneous control substrates, and onto laminin structures of grid- and line-shape was achieved. Cultures were evaluated by means of phase contrast microscopy, antibody staining, and patch-clamp measurements. Only patterns with line sizes of more than 4 microm yielded satisfactory neuronal outgrowth. The size of the nodes in the pattern influenced the nodal compliance of the spreading cells and the amount of unstructured overgrowth. Best grid patterns were 4 microm lines and 10 microm nodes, best line patterns were 4 microm lines and 20 microm nodes. On patterned substrates, average sodium and potassium currents were reduced by approximately 50% compared to controls, whereas area-normalized ion-currents were in the same order of magnitude. This indicates that as a consequence of the pattern-enforced geometrical confinement, neurons tend to have a smaller surface. In addition, neurons on patterned substrates were rapidly covered with glial overgrowth. This was shown by antibody staining. PMID:12102183

  17. Live imaging of microtubule dynamics in organotypic hippocampal slice cultures.

    PubMed

    Schätzle, Philipp; Kapitein, Lukas C; Hoogenraad, Casper C

    2016-01-01

    The microtubule (MT) cytoskeleton plays an active role during different phases of neuronal development and is an essential structure for stable neuronal morphology. MTs determine axon formation, control polarized cargo trafficking, and regulate the dynamics of dendritic spines, the major sites of excitatory synaptic input. Defects in MT function have been linked to various neurological and neurodegenerative diseases and recent studies highlight neuronal MTs as a potential target for therapeutic intervention. Thus, understanding MT dynamics and its regulation is of central importance to study many aspects of neuronal function. The dynamics of MT in neurons can be studied by visualizing fluorescently tagged MT plus-end tracking proteins (+TIPs). Tracking of +TIP trajectories allows analyzing the speeds and directionality of MT growth in axons and dendrites. Numerous labs now use +TIP to track growing MTs in dissociated neuron cultures. This chapter provides detailed methods for live imaging of MT dynamics in organotypic hippocampal slice cultures. We describe protocols for culturing and transducing organotypic slices and imaging MT dynamics by spinning disk confocal microscopy. PMID:26794510

  18. CT Coronary Angiography: 256-Slice and 320-Detector Row Scanners

    PubMed Central

    Hsiao, Edward M.; Rybicki, Frank J.; Steigner, Michael

    2010-01-01

    Multidetector computed tomography (MDCT) has rapidly evolved from 4-detector row systems in 1998 to 256-slice and 320-detector row CT systems. With smaller detector element size and faster gantry rotation speed, spatial and temporal resolution of the 64-detector MDCT scanners have made coronary artery imaging a reliable clinical test. Wide-area coverage MDCT, such as the 256-slice and 320-detector row MDCT scanners, has enabled volumetric imaging of the entire heart free of stair-step artifacts at a single time point within one cardiac cycle. It is hoped that these improvements will be realized with greater diagnostic accuracy of CT coronary angiography. Such scanners hold promise in performing a rapid high quality “triple rule-out” test without high contrast load, improved myocardial perfusion imaging, and even four-dimensional CT subtraction angiography. These emerging technical advances and novel applications will continue to change the way we study coronary artery disease beyond detecting luminal stenosis. PMID:20425186

  19. Capturing complex tumour biology in vitro: histological and molecular characterisation of precision cut slices

    PubMed Central

    Davies, Emma J.; Dong, Meng; Gutekunst, Matthias; Närhi, Katja; van Zoggel, Hanneke J. A. A.; Blom, Sami; Nagaraj, Ashwini; Metsalu, Tauno; Oswald, Eva; Erkens-Schulze, Sigrun; Delgado San Martin, Juan A.; Turkki, Riku; Wedge, Stephen R.; af Hällström, Taija M.; Schueler, Julia; van Weerden, Wytske M.; Verschuren, Emmy W.; Barry, Simon T.; van der Kuip, Heiko; Hickman, John A.

    2015-01-01

    Precision-cut slices of in vivo tumours permit interrogation in vitro of heterogeneous cells from solid tumours together with their native microenvironment. They offer a low throughput but high content in vitro experimental platform. Using mouse models as surrogates for three common human solid tumours, we describe a standardised workflow for systematic comparison of tumour slice cultivation methods and a tissue microarray-based method to archive them. Cultivated slices were compared to their in vivo source tissue using immunohistochemical and transcriptional biomarkers, particularly of cellular stress. Mechanical slicing induced minimal stress. Cultivation of tumour slices required organotypic support materials and atmospheric oxygen for maintenance of integrity and was associated with significant temporal and loco-regional changes in protein expression, for example HIF-1α. We recommend adherence to the robust workflow described, with recognition of temporal-spatial changes in protein expression before interrogation of tumour slices by pharmacological or other means. PMID:26647838

  20. Capturing complex tumour biology in vitro: histological and molecular characterisation of precision cut slices.

    PubMed

    Davies, Emma J; Dong, Meng; Gutekunst, Matthias; Närhi, Katja; van Zoggel, Hanneke J A A; Blom, Sami; Nagaraj, Ashwini; Metsalu, Tauno; Oswald, Eva; Erkens-Schulze, Sigrun; Delgado San Martin, Juan A; Turkki, Riku; Wedge, Stephen R; af Hällström, Taija M; Schueler, Julia; van Weerden, Wytske M; Verschuren, Emmy W; Barry, Simon T; van der Kuip, Heiko; Hickman, John A

    2015-01-01

    Precision-cut slices of in vivo tumours permit interrogation in vitro of heterogeneous cells from solid tumours together with their native microenvironment. They offer a low throughput but high content in vitro experimental platform. Using mouse models as surrogates for three common human solid tumours, we describe a standardised workflow for systematic comparison of tumour slice cultivation methods and a tissue microarray-based method to archive them. Cultivated slices were compared to their in vivo source tissue using immunohistochemical and transcriptional biomarkers, particularly of cellular stress. Mechanical slicing induced minimal stress. Cultivation of tumour slices required organotypic support materials and atmospheric oxygen for maintenance of integrity and was associated with significant temporal and loco-regional changes in protein expression, for example HIF-1α. We recommend adherence to the robust workflow described, with recognition of temporal-spatial changes in protein expression before interrogation of tumour slices by pharmacological or other means. PMID:26647838

  1. An Experimental Study of Critical Heat Flux in Narrow Gap With Two-Dimensional Slices

    SciTech Connect

    Yong Hoon Kim; Suh, Kune Y.; Rae Joon Park; San Baek Kim; Hee Dong Kim

    2002-07-01

    value because the power of the heaters was restricted by the three-dimensional (3D) geometry. The two-dimensional (2D) geometry relative to the 3D geometry enables the heaters to produce higher power. Experiments were conducted to develop the CHF correlation for gap cooling with the 2D slices. The experimental facility consisted of a heater, a pressure vessel, a heat exchanger and the pressure and temperature measurement system. Tests were carried out in the pressure range of 0.1 to 1 MPa for the gap sizes of 1 mm and 2 mm using demineralized water. (authors)

  2. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    PubMed

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (<1 years old) with CHD undergoing 128-slice CT prospective ECG-triggered axial scan, and 100 were selected randomly from 911 infants with CHD undergoing 64-slice CT retrospective ECG-gated spiral scan. The visibility of coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode. PMID:26271472

  3. Preparation of human formalin-fixed brain slices for electron microscopic investigations.

    PubMed

    Krause, Martin; Brüne, Martin; Theiss, Carsten

    2016-07-01

    Ultra-structural analysis of human post-mortem brain tissue is important for investigations into the pathomechanism of neuropsychiatric disorders, especially those lacking alternative models of studying human-specific morphological features. For example, Von Economo Neurons (VENs) mainly located in the anterior cingulate cortex and in the anterior part of the insula, which seem to play a role in a variety of neuropsychiatric conditions, including frontotemporal dementia, autism and schizophrenia, can hardly be studied in nonhuman animals. Accordingly, little is known about the ultra-structural alterations of these neurons, though important research using qualitative stereological methods has revealed that protein expression of the VENs assigns them a role in immune function. Formaldehyde, which is the most common fixative in human pathology, interferes with the immunoreactivity of the tissue, possibly leading to unreliable results. Therefore, a method for ultra-structural investigations independent of antigenic properties of the fixated tissue is needed. Here, we propose an approach using electron microscopy to examine cytoskeletal structures, synapses and mitochondria in these cells. We also show that our methodology is able to keep tissue consumption to a minimum, while still allowing for the specimens to be handled with ease by using agar embedded slices in contrast to blocks for the embedding procedure. Accordingly, a stepwise protocol utilising 60μm thick human post mortem brain sections for electron microscopic ultra-structural investigations is presented. PMID:27136748

  4. Critical Heat Flux Experiments on the Reactor Vessel Wall Using 2-D Slice Test Section

    SciTech Connect

    Jeong, Yong Hoon; Chang, Soon Heung; Baek, Won-Pil

    2005-11-15

    The critical heat flux (CHF) on the reactor vessel outer wall was measured using the two-dimensional slice test section. The radius and the channel area of the test section were 2.5 m and 10 cm x 15 cm, respectively. The flow channel area and the heater width were smaller than those of the ULPU experiments, but the radius was greater than that of the ULPU. The CHF data under the inlet subcooling of 2 to 25 deg. C and the mass flux 0 to 300 kg/m{sup 2}.s had been acquired. The measured CHF value was generally slightly lower than that of the ULPU. The difference possibly comes from the difference of the test section material and the thickness. However, the general trend of CHF according to the mass flux was similar with that of the ULPU. The experimental CHF data were compared with the predicted values by SULTAN correlation. The SULTAN correlation predicted well this study's data only for the mass flux higher than 200 kg/m{sup 2}.s, and for the exit quality lower than 0.05. The local condition-based correlation was developed, and it showed good prediction capability for broad quality (-0.01 to 0.5) and mass flux (<300 kg/m{sup 2}.s) conditions with a root-mean-square error of 2.4%. There were increases in the CHF with trisodium phosphate-added water.

  5. [Clinical applications of MALDI imaging using sliced sections of formalin-fixed paraffin-embedded tissues and longitudinal sliced hairs].

    PubMed

    Nakanishi, Toyofumi; Ito, Minako; Ueda, Kazuhito; Wada, Shinichi; Fujioka, Shigekazu; Tsuji, Motomu; Takubo, Takayuki

    2012-02-01

    MALDI-imaging MS (IMS) with MSMS analysis is a new powerful tool for the identification of not only disease-related proteins in formalin-fixed paraffin-embedded (FFPE) tissue sections but also protein/peptides/drugs/medicine in fresh-frozen tissues. IMS is used to reveal the mass profiles and spatial distribution of proteins in tissue sections and/or digested peptides derived from deposited protein in pathologic organs and then MSMS analysis identifies the amino acid sequence of the detected proteins in the tissue section. Moreover, on-tissue digestion combined with the MALDI-IM-TOF-IMS approach allows a proteomics "bottom-up" strategy with clinical samples, especially perioperative isolated tissues and FFPE tissues conserved for a long time in a clinical sample bank. The mass barcode-like image (MBI) on a longitudinal sliced hair by IMS is used in the selected reaction monitoring mode for serially chronological monitoring and traceability every few hours after drug and medicine intake. The advances of quantitative MBI for sliced sections of hair allow a new universal standardized assessment of drugs and medicines throughout the drug history. PMID:22568093

  6. High thickness acrylamide photopolymer for peristrophic multiplexing

    NASA Astrophysics Data System (ADS)

    Ortuño, M.; Fernández, E.; Márquez, A.; Gallego, S.; Neipp, C.; Pascual, I.

    2006-05-01

    The acrylamide photolymers are considered interesting materials for holographic media. They have high diffraction efficiency (ratio of the intensities of the diffracted and the incident beams), an intermediate energetic sensitivity among other materials and post-processing steps are not necessary, therefore the media is not altered. The layers of these materials, about 1 mm thick, are a suitable media for recording many diffraction gratings in the same volume of photopolymer using peristrophic multiplexing technique, with great practical importance in the field of holographic memories type WORM (write once read many). In this work we study the recording of diffraction gratings by peristrophic multiplexing with axis of rotation perpendicular to the recording media. The photopolymer is composed of acrylamide as the polymerizable monomer, triethanolamine as radical generator, yellowish eosin as sensitizer and a binder of polyvinyl alcohol. We analyze the holographic behaviour of the material during recording and reconstruction of diffraction gratings using a continuous Nd:YAG laser (532 nm) at an intensity of 5 mW/cm2 as recording laser. The response of the material is monitored after recording with an He-Ne laser. We study the recording process of unslanted diffraction gratings of 1125 lines/mm. The diffraction efficiency of each hologram is seen to decrease as the number of holograms recorded increases, due to consumption of the available dynamic range, in a constant exposure scheduling. It can be seen that the photopolymer works well with high energy levels, without excessive dispersion of light by noise gratings. In order to homogenize the diffraction efficiency of each hologram we use the method proposed by Pu. This method is designed to share all or part of the avaliable dynamic range of the recording material among the holograms to be multiplexed. Using exposure schedules derived from this method we have used 3 scheduling recordings from the algorithm used

  7. A variability study on the ASTM thin slicing and scaling test method for evaluating the long-term performance of an extruded polystyrene foam blown with HCFC-142b

    SciTech Connect

    Fabian, B.A.; Graves, R.S.; Yarbrough, D.W.; Hofton, M.R.

    1997-11-01

    The ASTM accelerated aging test method for unfaced foamboard insulation that is based on slicing and scaling has been used on an extruded polystyrene product blown with HCFC-142b. The test method including specimen preparation was carried out at three laboratories. The participating laboratories used different means to prepare thin test specimens. Thin slices of foamboard with and without surface skins were tested in order to assess the effect of skins on the aging process. Measured values for the apparent thermal conductivity, k{sub a}, were used to calculate time average k{sub a} for life-times of 10, 20, and 40 years. The time-average k{sub a} from the three laboratories differed by less than 2.5% for 1.5-inch-thick product and less than 2% for 2.0-inch-thick product. The k{sub a} for slices with skin on one surface were less than k{sub a} of slices of the core foam.

  8. Preparation of Nanoporous Pd by Dealloying Al-Pd Slice and Its Electrocatalysts for Formic Acid Oxidation

    NASA Astrophysics Data System (ADS)

    Yu, Nana; Wang, Tianning; Nie, Chen; Sun, Lanju; Li, Jie; Geng, Haoran

    2016-01-01

    AlPd alloy slices with a thickness of 0.5 mm were taken as precursors during the fabrication of nanoporous palladium (np-Pd) using chemical dealloying in NaOH solution or electrochemical dealloying in NaCl solution. Scanning electron microscope photos and x-ray diffraction patterns demonstrate a full dealloying of Al out of the precursors and the formation of nP-Pd which is characterized by a three-dimensional, bicontinuous, ligament-channel structure with nanoscale length scales. Electrochemical measurements were performed to evaluate the electrocatalytic activity and structure stability of np-Pd towards formic acid oxidation and it showed a good structure stability.

  9. Strong optomechanical interactions in a sliced photonic crystal nanobeam

    PubMed Central

    Leijssen, Rick; Verhagen, Ewold

    2015-01-01

    Coupling between mechanical and optical degrees of freedom is strongly enhanced by using subwavelength optical mode profiles. We realize an optomechanical system based on a sliced photonic crystal nanobeam, which combines such highly confined optical fields with a low-mass mechanical mode. Analyzing the transduction of motion and effects of radiation pressure we find the system exhibits a photon-phonon coupling rate g0 /2π ≈ 11.5 MHz, exceeding previously reported values by an order of magnitude. We show that the large optomechanical interaction enables detecting thermal motion with detection noise below that at the standard quantum limit, even in broad bandwidth devices, important for both sensor applications as well as measurement-based quantum control. PMID:26522751

  10. Maximal slicing of D-dimensional spherically symmetric vacuum spacetime

    SciTech Connect

    Nakao, Ken-ichi; Abe, Hiroyuki; Yoshino, Hirotaka; Shibata, Masaru

    2009-10-15

    We study the foliation of a D-dimensional spherically symmetric black-hole spacetime with D{>=}5 by two kinds of one-parameter families of maximal hypersurfaces: a reflection-symmetric foliation with respect to the wormhole slot and a stationary foliation that has an infinitely long trumpetlike shape. As in the four-dimensional case, the foliations by the maximal hypersurfaces avoid the singularity irrespective of the dimensionality. This indicates that the maximal slicing condition will be useful for simulating higher-dimensional black-hole spacetimes in numerical relativity. For the case of D=5, we present analytic solutions of the intrinsic metric, the extrinsic curvature, the lapse function, and the shift vector for the foliation by the stationary maximal hypersurfaces. These data will be useful for checking five-dimensional numerical-relativity codes based on the moving puncture approach.

  11. Geometric and kinematic modelling of a human costal slice.

    PubMed

    Minotti, P; Lexcellent, C

    1991-01-01

    More and more powerful calculation methods are being used in the modelization of the human thorax, and considering the progress made in the domain of numerical analysis, this modelization is naturally being oriented toward the utilization of finite element methods. However, thoracic models are usually based on extremely simple geometric hypotheses, due mostly to the lack of dependable experimental data. Hence, the exploitation of sophisticated software is far from optimal. This study is based on experimental observations which allow the capabilities of the current means of calculation to be exploited to a maximum. The objectives of the study are the geometric and kinematic representations of a typical costal slice. A precise topographical measurement, performed by a robot, allows description of the costal geometry. The exploitation of these measurements then allows the identification of the costo-vertebral articulation. PMID:2055910

  12. Measurement of Inositol Triphosphate Levels from Rat Hippocampal Slices

    PubMed Central

    Tabatadze, Nino; Woolley, Catherine

    2016-01-01

    Inositol triphosphate (IP3) is an important second messenger that participates in signal transduction pathways in diverse cell types including hippocampal neurons. Stimulation of phospholipase C in response to various stimuli (hormones, growth factors, neurotransmitters, neurotrophins, neuromodulators, odorants, light, etc) results in hydrolysis of phosphatidylinositol 4, 5-bisphosphate (PIP2), a phospholipid that is located in the plasma membrane, and leads to the production of IP3 and diacylglycerol. Binding of IP3 to the IP3 receptor (IP3R) induces Ca2+ release from intracellular stores and enables the initiation of intracellular Ca2+-dependent signaling. Here we describe a procedure for the measurement of cellular IP3 levels in tissue homogenates prepared from rat hippocampal slices.

  13. Optical slicing of large scenes by synthetic aperture integral imaging

    NASA Astrophysics Data System (ADS)

    Navarro, Héctor; Saavedra, Genaro; Molina, Ainhoa; Martínez-Corral, Manuel; Martínez-Cuenca, Raúl; Javidi, Bahram

    2010-04-01

    Integral imaging (InI) technology was created with the aim of providing the binocular observers of monitors, or matrix display devices, with auto-stereoscopic images of 3D scenes. However, along the last few years the inventiveness of researches has allowed to find many other interesting applications of integral imaging. Examples of this are the application of InI in object recognition, the mapping of 3D polarization distributions, or the elimination of occluding signals. One of the most interesting applications of integral imaging is the production of views focused at different depths of the 3D scene. This application is the natural result of the ability of InI to create focal stacks from a single input image. In this contribution we present new algorithm for this optical slicing application, and show that it is possible the 3D reconstruction with improved lateral resolution.

  14. Ring artifacts removal from synchrotron CT image slices

    NASA Astrophysics Data System (ADS)

    Wei, Zhouping; Wiebe, Sheldon; Chapman, Dean

    2013-06-01

    Ring artifacts can occur in reconstructed images from x-ray Computerized Tomography (CT) as full or partial concentric rings superimposed on the scanned structures. Due to the data corruption by those ring artifacts in CT images, qualitative and quantitative analysis of these images are compromised. In this paper, we propose to correct the ring artifacts on the reconstructed synchrotron radiation (SR) CT image slices. The proposed correction procedure includes the following steps: (1). transform the reconstructed CT images into polar coordinates; (2) apply discrete two-dimensional (2D) wavelet transform to the polar image to decompose it into four image components: low pass band image component, as well as the components from horizontal, vertical and diagonal details bands; (3). apply 2D Fourier transform to the vertical details band image component only, since the ring artifacts become vertical lines in the polar coordinates; (4). apply Gaussian filtering in Fourier domain along the abscissa direction to suppress the vertical lines, since the information of the vertical lines in Fourier domain is completely condensed to that direction; (5). perform inverse Fourier transform to get the corrected vertical details band image component; (6). perform inverse wavelet transform to get the corrected polar image; (7). transform the corrected polar image back to Cartesian coordinates to get the CT image slice with reduced ring artifacts. This approach has been successfully used on CT data acquired from the Biomedical Imaging and Therapy (BMIT) beamline in Canadian Light Source (CLS), and the results show that the ring artifacts in original SR CT images have been effectively suppressed with all the structure information in the image preserved.

  15. Persistent Gliosis Interferes with Neurogenesis in Organotypic Hippocampal Slice Cultures.

    PubMed

    Gerlach, Johannes; Donkels, Catharina; Münzner, Gert; Haas, Carola A

    2016-01-01

    Neurogenesis in the adult hippocampus has become an intensively investigated research topic, as it is essential for proper hippocampal function and considered to bear therapeutic potential for the replacement of pathologically lost neurons. On the other hand, neurogenesis itself is frequently affected by CNS insults. To identify processes leading to the disturbance of neurogenesis, we made use of organotypic hippocampal slice cultures (OHSC), which, for unknown reasons, lose their neurogenic potential during cultivation. In the present study, we show by BrdU/Prox1 double-immunostaining that the generation of new granule cells drops by 90% during the first week of cultivation. Monitoring neurogenesis dynamically in OHSC from POMC-eGFP mice, in which immature granule cells are endogenously labeled, revealed a gradual decay of the eGFP signal, reaching 10% of initial values within 7 days of cultivation. Accordingly, reverse transcription quantitative polymerase chain reaction analysis showed the downregulation of the neurogenesis-related genes doublecortin and Hes5, a crucial target of the stem cell-maintaining Notch signaling pathway. In parallel, we demonstrate a strong and long-lasting activation of astrocytes and microglial cells, both, morphologically and on the level of gene expression. Enhancement of astroglial activation by treating OHSC with ciliary neurotrophic factor accelerated the loss of neurogenesis, whereas treatment with indomethacin or an antagonist of the purinergic P2Y12 receptor exhibited potent protective effects on the neurogenic outcome. Therefore, we conclude that OHSC rapidly lose their neurogenic capacity due to persistent inflammatory processes taking place after the slice preparation. As inflammation is also considered to affect neurogenesis in many CNS pathologies, OHSC appear as a useful tool to study this interplay and its molecular basis. Furthermore, we propose that modification of glial activation might bear the therapeutic potential

  16. Quality of tomato slices disinfected with ozonated water.

    PubMed

    Aguayo, Encarna; Escalona, Víctor; Silveira, Ana Cecilia; Artés, Francisco

    2014-04-01

    Fresh-cut industry needs novel disinfectant to replace the use of chlorine. Ozone is one of the most powerful oxidizing agents and is applied in gaseous or aqueous form for sanitation purposes. However, the strong oxidative effect could affect the nutritional and sensorial quality, in particular, when time of washing is extended. For that reason, the overall impact of ozonated water (0.4 mg/L) dipping applied during 1, 3 and 5 min compared to control washed in water during 5 min was studied in tomato slices stored during 14 days at 5 . According to the results, ozonated water treatment of 3 min achieved the best firmness retention, microbial quality (mesophilic, psychrotrophic and yeas load) and reduced the consumption of fructose and glucose. The use of ozonated water did not affect the total acidity, pH, total solid soluble, organic acid as ascorbic, fumaric or succinic acid and the sensorial parameters, which were only affected by storage time. However, the poor appearance, aroma and overall quality obtained in all treatments prevented shelf life of 14 days and the quality at acceptable levels was established in 10 days at 5 . It is recommended to wash tomato slices with 0.4 mg/L ozonated water for 3 min only. Extending treatment duration did not improve the microbiological quality, possibly due to the extra time permitting the ozone to react with other components of the fruit tissue, undermining the antimicrobial benefits. PMID:23774605

  17. True Density Prediction of Garlic Slices Dehydrated by Convection.

    PubMed

    López-Ortiz, Anabel; Rodríguez-Ramírez, Juan; Méndez-Lagunas, Lilia

    2016-01-01

    Physiochemical parameters with constant values are employed for the mass-heat transfer modeling of the air drying process. However, structural properties are not constant under drying conditions. Empirical, semi-theoretical, and theoretical models have been proposed to describe true density (ρp). These models only consider the ideal behavior and assume a linear relationship between ρp and moisture content (X); nevertheless, some materials exhibit a nonlinear behavior of ρp as a function of X with a tendency toward being concave-down. This comportment, which can be observed in garlic and carrots, has been difficult to model mathematically. This work proposes a semi-theoretical model for predicting ρp values, taking into account the concave-down comportment that occurs at the end of the drying process. The model includes the ρs dependency on external conditions (air drying temperature (Ta)), the inside temperature of the garlic slices (Ti ), and the moisture content (X) obtained from experimental data on the drying process. Calculations show that the dry solid density (ρs ) is not a linear function of Ta, X, and Ti . An empirical correlation for ρs is proposed as a function of Ti and X. The adjustment equation for Ti is proposed as a function of Ta and X. The proposed model for ρp was validated using experimental data on the sliced garlic and was compared with theoretical and empirical models that are available in the scientific literature. Deviation between the experimental and predicted data was determined. An explanation of the nonlinear behavior of ρs and ρp in the function of X, taking into account second-order phase changes, are then presented. PMID:26666973

  18. Persistent Gliosis Interferes with Neurogenesis in Organotypic Hippocampal Slice Cultures

    PubMed Central

    Gerlach, Johannes; Donkels, Catharina; Münzner, Gert; Haas, Carola A.

    2016-01-01

    Neurogenesis in the adult hippocampus has become an intensively investigated research topic, as it is essential for proper hippocampal function and considered to bear therapeutic potential for the replacement of pathologically lost neurons. On the other hand, neurogenesis itself is frequently affected by CNS insults. To identify processes leading to the disturbance of neurogenesis, we made use of organotypic hippocampal slice cultures (OHSC), which, for unknown reasons, lose their neurogenic potential during cultivation. In the present study, we show by BrdU/Prox1 double-immunostaining that the generation of new granule cells drops by 90% during the first week of cultivation. Monitoring neurogenesis dynamically in OHSC from POMC-eGFP mice, in which immature granule cells are endogenously labeled, revealed a gradual decay of the eGFP signal, reaching 10% of initial values within 7 days of cultivation. Accordingly, reverse transcription quantitative polymerase chain reaction analysis showed the downregulation of the neurogenesis-related genes doublecortin and Hes5, a crucial target of the stem cell-maintaining Notch signaling pathway. In parallel, we demonstrate a strong and long-lasting activation of astrocytes and microglial cells, both, morphologically and on the level of gene expression. Enhancement of astroglial activation by treating OHSC with ciliary neurotrophic factor accelerated the loss of neurogenesis, whereas treatment with indomethacin or an antagonist of the purinergic P2Y12 receptor exhibited potent protective effects on the neurogenic outcome. Therefore, we conclude that OHSC rapidly lose their neurogenic capacity due to persistent inflammatory processes taking place after the slice preparation. As inflammation is also considered to affect neurogenesis in many CNS pathologies, OHSC appear as a useful tool to study this interplay and its molecular basis. Furthermore, we propose that modification of glial activation might bear the therapeutic potential

  19. Choroidal thickness in pregnant women: a cross-sectional study

    PubMed Central

    Liu, Ru; Kuang, Guo-Ping; Luo, Di-Xian; Lu, Xiao-He

    2016-01-01

    AIM To investigate choroidal thickness in pregnant women and compare the measurements with those of normal nonpregnant women. METHODS Using enhanced depth imaging optical coherence tomography (EDI-OCT), choroidal thickness was measured at the fovea and at 1 mm and 3 mm superior, inferior, temporal, and nasal to the fovea in both healthy pregnant women and nonpregnant women. Pearson correlation analysis was performed to evaluate the relationships between subfoveal choroidal thickness (SFCT) and the demographic and ocular parameters. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects model when Meta-analyses were conducted. RESULTS Comparison of choroidal thickness between the groups showed that it was significantly greater in healthy pregnant women's eyes than in normal nonpregnant women's eyes at all locations except at 3 mm superior and 3 mm temporal from the fovea (P<0.05). The mean SFCT was 344.13±50.94 µm in healthy pregnant women's eyes and 315.03±60.57 µm in normal nonpregnant women's eyes, with a statistically significant difference (P=0.008). Pearson correlation analysis showed that age and axial length were significantly related to SFCT in healthy pregnant women, normal nonpregnant women, and all subjects. The results of our cross-sectional study were consistent with the results of the further Meta-analysis, with a pooled weighted mean difference (WMD) of 33.66 µm (95% CI: 26.16 to 41.15) for SFCT. CONCLUSION Our results, along with the comprehensive Meta-analysis, suggest that choroidal thickness in healthy pregnant women is greater than that in normal nonpregnant women. PMID:27588276

  20. 3D resolved mapping of optical aberrations in thick tissues

    PubMed Central

    Zeng, Jun; Mahou, Pierre; Schanne-Klein, Marie-Claire; Beaurepaire, Emmanuel; Débarre, Delphine

    2012-01-01

    We demonstrate a simple method for mapping optical aberrations with 3D resolution within thick samples. The method relies on the local measurement of the variation in image quality with externally applied aberrations. We discuss the accuracy of the method as a function of the signal strength and of the aberration amplitude and we derive the achievable resolution for the resulting measurements. We then report on measured 3D aberration maps in human skin biopsies and mouse brain slices. From these data, we analyse the consequences of tissue structure and refractive index distribution on aberrations and imaging depth in normal and cleared tissue samples. The aberration maps allow the estimation of the typical aplanetism region size over which aberrations can be uniformly corrected. This method and data pave the way towards efficient correction strategies for tissue imaging applications. PMID:22876353

  1. Quantitative analysis of myocardial perfusion SPECT anatomically guided by co-registered 64-slice coronary CT angiography

    PubMed Central

    Slomka, Piotr J.; Cheng, Victor Y.; Dey, Damini; Woo, Jonghye; Ramesh, Amit; Kriekinge, Serge Van; Suzuki, Yasuzuki; Elad, Yaron; Karlsberg, Ronald; Berman, Daniel S.; Germano, Guido

    2012-01-01

    Aim Sequential testing by coronary computed tomography angiography (CTA) and myocardial perfusion SPECT (MPS) obtained on standalone scanners may be needed to diagnose coronary artery disease (CAD) in equivocal cases. We have developed an automated technique for MPS-CTA registration and demonstrate its utility for improved MPS quantification by guiding the co-registered physiological (MPS) with anatomical CTA information. Methods Automated registration of MPS left ventricular (LV) surfaces with CTA coronary trees was accomplished by iterative minimization of voxel differences between pre-segmented CTA volumes and “motion-frozen” MPS data. Studies of 35 sequential patients (26 males), mean age 67±12 years with 64-slice coronary CTA, MPS and with available results of the invasive coronary angiography performed within 3 months were retrospectively analyzed. 3D coronary vessels and CTA slices were extracted and fused with quantitative MPS results mapped on LV surfaces and MPS coronary regions. Automatically co-registered CTA images and extracted trees were used to correct the MPS contours and to adjust the standard vascular region definitions for MPS quantification. Results Automated co-registration of MPS and coronary CTA had the success rate of 96% as assessed visually; the average errors were 4.3±3.3 mm in translation and 1.5±2.6 deg in rotation on stress and 4.2±3.1 mm in translation and 1.7±3.2 deg in rotation on rest. MPS vascular region definition was adjusted in 17 studies and LV contours were adjusted in 11 studies using co-registered CTA images as a guide. CTA-guided MP analysis resulted in improved area under the receiver operator characteristics (ROC) curves for the detection of RCA and LCX lesions as compared to standard MPS analysis 0.84±0.08 vs. 0.70±0.11 for LCX (p = 0.03) and 0.92±0.05 vs. 0.75±0.09 (p=0.02) for RCA. Conclusions Software image co-registration of standalone coronary CTA and MPS obtained on separate scanners can be performed

  2. STM observation of damage on HOPG induced by energetic ions escaped from thick botanic samples*

    NASA Astrophysics Data System (ADS)

    Liu, Feng; Wang, Yugang; Xue, Jianming; Wang, Sixue; Yan, Sha; Zhao, Weijiang

    2001-05-01

    The target samples of 30-100 μm thick slices of kidney bean dry seeds and 8 and 72 μm ethylene terephthalate (PET) films were irradiated by 40 keV N + ion beam. The current density was 8 μA/cm 2 and the fluency was in the range of 0.3-3×10 17 ions/cm 2. During ion irradiation, highly oriented pyrolytic graphite (HOPG) samples were placed behind the target samples to receive energetic ions. After irradiation, through scanning tunneling microscope (STM) observation, statistic number density of protrusion-like damage on HOPG surfaces have been obtained. The experimental results show that for 30 and 50 μm thick botanic slice samples, the number densities are 1.0-5.0×10 11 and 0.6-2×10 10/cm 2, respectively. It demonstrates that 40 keV N + ion irradiation can cause evident damage at a depth of 50 μm in dry kidney bean seed slices. Before and after low-energy ion irradiation, transmission spectra of MeV proton with low fluency rate were applied to examine those botanic samples and study the possible escaping mechanism of the energetic ions from them in the low-energy ion irradiation.

  3. The Utility of Thin Slice Ratings for Predicting Language Growth in Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Walton, Katherine M.; Ingersoll, Brooke R.

    2016-01-01

    Literature on "Thin Slice" ratings indicates that a number of personality characteristics and behaviors can be accurately predicted by ratings of very short segments (<5?min) of behavior. This study examined the utility of Thin Slice ratings of young children with autism spectrum disorder for predicting developmental skills and…

  4. Development and characterization of an ex-vivo brain slice culture model of chronic wasting disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prion diseases have long incubation times in vivo, therefore, modeling the diseases ex-vivo will advance the development of rationale-based therapeutic strategies. An organotypic slice culture assay (POSCA) was recently developed for scrapie prions by inoculating mouse cerebellar brain slices with R...

  5. Cold plasma reduces Salmonella on sliced roma tomatoes: efficacy of air versus nitrogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rapid, waterless, contact-free method of decontamination for tomatoes and tomato slices is of interest to processors and the food service industry. Cold plasma is a novel antimicrobial treatment for fresh and fresh-cut fruits and vegetables. Slices of Roma tomatoes were spot inoculated with three ...

  6. SLICE Office Quarterly Report for the Period January 1, 1973 to March 31, 1973.

    ERIC Educational Resources Information Center

    Southwestern Library Interstate Cooperative Endeavor, Dallas, TX.

    One purpose of this report is to communicate with all interested parties the status of the Southwestern Library Interstate Cooperative Endeavor (SLICE) Project as of March 31, 1973. A second - and very important - purpose is to stimulate and solicite "feedback," suggestions and guidance for future SLICE Office activities. Candid evaluation and…

  7. SLICE Office Report for the Period April 1, 1974 to June 30, 1974.

    ERIC Educational Resources Information Center

    Southwestern Library Interstate Cooperative Endeavor, Dallas, TX.

    The activities of the Southwestern Library Cooperative Endeavor (SLICE) project are directed to those concerned with regional, multi-state library networks and continuing education for library staffs. Two SLICE projects are reviewed in this quarterly report: the planning of a six-state regional bibliographic network, and continuing education for…

  8. Non-enzymatic browning and flavour kinetics of vacuum dried onion slices

    NASA Astrophysics Data System (ADS)

    Mitra, Jayeeta; Shrivastava, Shanker L.; Rao, Pavuluri S.

    2015-01-01

    Onion slices were dehydrated under vacuum to produce good quality dried ready-to-use onion slices. Colour development due to non-enzymatic browning and flavour loss in terms of thiosulphinate concentration was determined, along with moisture content and rehydration ratio. Kinetics of non-enzymatic browning and thiosulphinate loss during drying was analysed. Colour change due to non-enzymatic browning was found to be much lower in the case of vacuum dried onion, and improved flavour retention was observed as compared to hot air dried onion slices. The optical index values for non-enzymatic browning varied from 18.41 to 38.68 for untreated onion slices and from 16.73 to 36.51 for treated slices, whereas thiosulphinate concentration in the case of untreated onion slices was within the range of 2.96-3.92 μmol g-1 for dried sample and 3.71-4.43 μmol g-1 for the treated onion slices. Rehydration ratio was also increased, which may be attributed to a better porous structure attained due to vacuum drying. The treatment applied was found very suitable in controlling non-enzymatic browning and flavour loss during drying, besides increasing rehydration ratio. Hence, high quality dried ready- to-use onion slices were prepared.

  9. Comparing Thin Slices of Verbal Communication Behavior of Varying Number and Duration

    PubMed Central

    Carcone, April Idalski; Naar-King, Sylvie; Eggly, Susan; Foster, Tanina; Albrecht, Terrance; Brogan, Kathryn

    2014-01-01

    Objective The aim of this study was to assess the accuracy of thin slices to characterize the verbal communication behavior of counselors and patients engaged in Motivational Interviewing sessions relative to fully coded sessions. Methods Four thin slice samples that varied in number (four versus six slices) and duration (one- versus two-minutes) were extracted from a previously coded dataset. In the parent study, an observational code scheme was used to characterize specific counselor and patient verbal communication behaviors. For the current study, we compared the frequency of communication codes and the correlations among the full dataset and each thin slice sample. Results Both the proportion of communication codes and strength of the correlation demonstrated the highest degree of accuracy when a greater number (i.e., six versus four) and duration (i.e., two- versus one-minute) of slices were extracted. Conclusion These results suggest that thin slice sampling may be a useful and accurate strategy to reduce coding burden when coding specific verbal communication behaviors within clinical encounters. Practice Implications We suggest researchers interested in using thin slice sampling in their own work conduct preliminary research to determine the number and duration of thin slices required to accurately characterize the behaviors of interest. PMID:25441095

  10. UPTAKE OF INORGANIC LEAD IN VITRO BY ISOLATED MITOCHONDRIA AND TISSUE SLICES OF RAT RENAL CORTEX

    EPA Science Inventory

    Slices of rat renal cortex were shown to take up Pb2+ during incubation in vitro; Pb2+ was also shown to enter mitochondria within the slices. The uptake of Pb2+ by isolated mitochondria was inhibited by N3-, La3+ and ruthenium red. A steady state of uptake was attained within 60...

  11. Acute brain slice methods for adult and aging animals: application of targeted patch clampanalysis and optogenetics

    PubMed Central

    Daigle, Tanya L.; Chen, Qian; Feng, Guoping

    2014-01-01

    Summary The development of the living acute brain slice preparation for analyzing synaptic function roughly a half century ago was a pivotal achievement that greatly influenced the landscape of modern neuroscience. Indeed, many neuroscientists regard brain slices as the gold-standard model system for detailed cellular, molecular, and circuitry level analysis and perturbation of neuronal function. A critical limitation of this model system is the difficulty in preparing slices from adult and aging animals, and over the past several decades few substantial methodological improvements have emerged to facilitate patch clamp analysis in the mature adult stage. In this chapter we describe a robust and practical protocol for preparing brain slices from mature adult mice that are suitable for patch clamp analysis. This method reduces swelling and damage in superficial layers of the slices and improves the success rate for targeted patch clamp recordings, including recordings from fluorescently labeled populations in slices derived from transgenic mice. This adult brain slice method is suitable for diverse experimental applications, including both monitoring and manipulating neuronal activity with genetically encoded calcium indicators and optogenetic actuators, respectively. We describe the application of this adult brain slice platform and associated methods for screening kinetic properties of Channelrhodopsin (ChR) variants expressed in genetically-defined neuronal subtypes. PMID:25023312

  12. Measuring Thicknesses of Wastewater Films

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Davenport, R. J.

    1987-01-01

    Sensor determines when thickness of film of electrically conductive wastewater on rotating evaporator drum exceeds preset value. Sensor simple electrical probe that makes contact with liquid surface. Made of materials resistant to chemicals in liquid. Mounted on shaft in rotating cylinder, liquid-thickness sensor extends toward cylinder wall so tip almost touches. Sensor body accommodates probe measuring temperature of evaporated water in cylinder.

  13. Association between choroidal thickness and anterior chamber segment in eyes with narrow or open-angle

    PubMed Central

    Li, Song-Feng; Wu, Ge-Wei; Chen, Chang-Xi; Shen, Ling; Zhang, Zhi-Bao; Gao, Fei; Wang, Ning-Li

    2016-01-01

    AIM To investigate the relationship between choroidal thickness and anterior chamber segment in subjects with eyes with narrow or open-angle. METHODS The subfoveal choroidal thickness was measured with enhanced depth-imaging optical coherence tomography and anterior chamber parameters were measured with ultrasound biomicroscopy in one eye of 23 subjects with open-angle eyes and 38 subjects with narrow-angle eyes. The mean age was 59.52±7.04y for narrow-angle subjects and 60.76±7.23y for open-angle subjects (P=0.514). Multivariate linear regression analysis was performed to assess the association between choroidal thickness and narrow-angle parameters. RESULTS There were no differences in subfoveal choroidal thickness between open- and narrow-angle subjects (P=0.231). Anterior chamber parameters, including central anterior chamber depth, trabecular iris angle, iris thickness 500 µm from the scleral spur (IT500), and ciliary body thickness at 1 mm and 2 mm from the scleral spur (CBT1, CBT2) showed significant differences between the two groups (P<0.05). Subfoveal choroidal thickness showed negative correlation (β=-0.496, P=0.016) only with anterior chamber depth in the open-angle group and with age (β=-0.442, P=0.003) and IT500 (β=-0.399, P=0.008) in the narrow-angle group. However, subfoveal choroidal thickness was not correlated with trabecular iris angle, anterior chamber depth, ciliary body thickness, or central corneal thickness in the narrow-angle group. CONCLUSION Choroidal thickness does not differ in the two groups and has not correlated with anterior chamber parameters in narrow-angle subjects, suggesting a lack of relationship between choroidal thickness and primary angle-closure glaucoma. PMID:27588269

  14. Extended Coverage First-Pass Perfusion Imaging Using Slice-Interleaved TSENSE

    PubMed Central

    Kellman, P.; Derbyshire, J.A.; Agyeman, K.O.; McVeigh, E.R.; Arai, A.E.

    2007-01-01

    Parallel imaging applied to first-pass, contrast-enhanced cardiac MR can yield greater spatial coverage for a fixed temporal resolution. The method combines rate R = 2 acceleration using TSENSE with shot-to-shot interleaving of two slices. The √R SNR loss is largely compensated for by a longer effective repetition time (TR) and increased flip angle associated with slice interleaving. In this manner, increased spatial coverage is achieved while comparable or better image quality is maintained. Single-heartbeat temporal resolution was accomplished with spatial coverage of eight slices at heart rates up to 71 bpm, six slices up to 95 bpm, and four slices up to 143 bpm. Experiments in normal subjects (N = 6) were performed to assess signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) values. Published 2003 Wiley-Liss, Inc.† PMID:14705062

  15. Preparation of Gene Gun Bullets and Biolistic Transfection of Neurons in Slice Culture

    PubMed Central

    Woods, Georgia; Zito, Karen

    2008-01-01

    Biolistic transfection is a physical means of transfecting cells by bombarding tissue with high velocity DNA coated particles. We provide a detailed protocol for biolistic transfection of rat hippocampal slices, from the initial preparation of DNA coated bullets to the final shooting of the organotypic slice cultures using a gene gun. Gene gun transfection is an efficient and easy means of transfecting neurons and is especially useful for fluorescently labeling a small subset of cells in tissue slice. In this video, we first outline the steps required to coat gold particles with DNA. We next demonstrate how to line the inside of plastic tubing with the gold/DNA bullets, and how to cut this tubing to obtain the plastic cartridges for loading into the gene gun. Finally, we perform biolistic transfection of rat hippocampal slice cultures, demonstrating handling of the Bio-Rad Helios gene gun, and offering trouble shooting advice to obtain healthy and optimally transfected tissue slices. PMID:19066564

  16. Imaging study on the optic canal using sixty four-slice spiral computed tomography

    PubMed Central

    Jiang, Peng-Fei; Dai, Xiu-Yu; Lv, Yongbin; Liu, Shaoyi; Mu, Xiao-Yan

    2015-01-01

    Background: Rapid advances in multislice computed tomography (MSCT) technology facilitate accurate clinical imaging. The newly developed 64-slice CT increases temporal and spatial resolution efficiently. Purpose: The purpose of this study is to evaluate the application of 64 slice spiral computed tomography (CT) on the imaging of the normal optics canal. Methods and materials: 100 healthy adults were investigated using 64 slice spiral CT. The optics canal was scanned, reconstructed and examined. Results: Among the four walls of the optic canal, the medial wall is the longest one. The upper wall and outer wall are inferior to the medial wall while the inferior wall is the shortest one. All the data accomplished by the 64 slice CT was consistent with the results of previous reports using other methods. Conclusion: The results suggested that the 64 slice spiral CT could be a valuable and accurate method for measuring the length of optics canal walls. PMID:26885062

  17. Simultaneous time-temperature-thickness superposition theoretical and statistical modelling of convective drying of guava.

    PubMed

    Kek, Siok Peng; Chin, Nyuk Ling; Yusof, Yus Aniza

    2014-12-01

    Modelling studies of guava drying and quality are presented using theoretical and statistical models by varying temperature from 55 to 75 °C and slice thickness from 3 to 9 mm. The quality of dried fruit was measured for its water activity, colour, vitamin C, and texture. The superposition technique with Midilli-Kucuk model showed efficiency in modelling the drying process with R (2)  = 0.9991. The second-order polynomial equations adequately described the quality of dried guava with regression coefficient, R (2)  > 0.7. Drying time was a good function of temperature and thickness (P < 0.001); water activity, colour and vitamin C showed strong dependence on temperature (P < 0.1); while texture was mainly influenced by its thickness (P < 0.005). The optimum drying temperature of 70 °C at slice thickness of 6 mm was determined using the desirability function method. Simultaneous modelling using the theoretical and statistical drying models provides information on water diffusion and evaporation with the drying responses and factors. PMID:25477628

  18. Evaluation of the effect of geometry for measuring section thickness in tomosynthesis.

    PubMed

    Fukui, Ryohei; Ishii, Rie; Kishimoto, Junichi; Yamato, Shinichiro; Takahata, Akira; Kohama, Chiyuki

    2014-01-01

    Our aim in this study was to evaluate the effect of geometry for measuring section thickness in tomosynthesis by using a metal bead device (bead method). Tomosynthesis images were obtained from two types of tomosynthesis equipment, Safire17 (ST, Shimadzu, Kyoto, Japan) and XR650 (GT, GE Healthcare, Milwaukee, WI). After tomosynthesis radiography with each device, the bead tomosynthesis images were obtained by image reconstruction. The digital profile was obtained from the digital value of the bead central coordinate in the perpendicular direction, and we acquired the slice sensitivity profile (SSP). The section thickness was defined with the full width at half maximum obtained from the SSP. We investigated the change in section thickness under different evaluation conditions: the angular range, the height of the bead position, the source-image receptor distance (SID), and image processing. The section thickness decreased when the angular range and height of the bead position increased. Also, the section thickness varied with a change in the SID. The section thickness differed according to the geometry for measuring the section thickness. Thus, the effect of the geometry used for measurement should be considered when the section thickness in tomosynthesis is measured by the bead method. PMID:24254729

  19. Influence of stack plate thickness and voltage input on the performance of loudspeaker-driven thermoacoustic refrigerator

    NASA Astrophysics Data System (ADS)

    Putra, Nandy; Agustina, Dinni

    2013-04-01

    A loudspeaker-driven thermoacoustic refrigerator has been built and tested to gain understanding of its thermal performance and the cooling rate. The influence of plate thickness made of acrylic sheet was experimentally investigated by varying plate thickness of the stack, 0.15 mm, 0.5 mm and 1 mm, respectively. The experiments were conducted with various voltage input to the driver starting from setting 4 to 9 voltage peak-to-peak. The temperatures at both ends of the stack were acquired. For all variations, thermoacoustic cooling effect occurred in seconds and escalated rapidly in two minutes and became stable in ten-minute time. The experimental results showed that higher voltage input yielded higher thermal performance and faster cooling rate. For each set of experiment, the operating frequency and other parameters of the stack were kept unchanged. The experimental results show that the thermal performance and cooling rate increase with the decrease of plate thickness. The largest temperature difference, 14.8°C, was achieved with 0.1 mm plate thickness at voltage setting 9. However, the thermal performance gained for 0.5 mm plate thickness voltage setting of 9, was arguably the optimum thickness in terms of advantages in the ease of fabricating the stack and more consistent cooling.

  20. Neocortical slices from adult chronic epileptic rats exhibit discharges of higher voltages and broader spread.

    PubMed

    Serafini, R; Dettloff, S; Loeb, J A

    2016-05-13

    Much of the current understanding of epilepsy mechanisms has been built on data recorded with one or a few electrodes from temporal lobe slices of normal young animals stimulated with convulsants. Mechanisms of adult, extratemporal, neocortical chronic epilepsy have not been characterized as much. A more advanced understanding of epilepsy mechanisms can be obtained by recording epileptiform discharges simultaneously from multiple points of an epileptic focus so as to define their sites of initiation and pathways of spreading. Brain slice recordings can characterize epileptic mechanisms in a simpler, more controlled preparation than in vivo. Yet, the intrinsic hyper-excitability of a chronic epileptic focus may not be entirely preserved in slices following the severing of connections in slice preparation. This study utilizes recordings of multiple electrode arrays to characterize which features of epileptic hyper-excitability present in in vivo chronic adult neocortical epileptic foci are preserved in brain slices. After tetanus toxin somatosensory cortex injections, adult rats manifest chronic spontaneous epileptic discharges both in the injection site (primary focus) and in the contralateral side (secondary focus). We prepared neocortical slices from these epileptic animals. When perfused with 4-Aminopyridine in a magnesium free medium, epileptic rat slices exhibit higher voltage discharges and broader spreading than control rat slices. Rates of discharges are similar in slices of epileptic and normal rats, however. Ictal and interictal discharges are distributed over most cortical layers, though with significant differences between primary and secondary foci. A chronic neocortical epileptic focus in slices does not show increased spontaneous pacemakers initiating epileptic discharges but shows discharges with higher voltages and broader spread, consistent with an enhanced synchrony of cellular and synaptic generators over wider surfaces. PMID:26892299

  1. Near-infrared imaging equipment that detects small organic substances in thick foods

    NASA Astrophysics Data System (ADS)

    Phetchalern, Souphaphone; Tashima, Hiroto; Ishii, Yuya; Ishiyama, Takeshi; Arai, Shinichi; Fukuda, Mitsuo

    2014-09-01

    We have developed near-infrared imaging equipment that can detect small organic substances in foodstuffs with thicknesses of more than 1 mm. The equipment is composed of a high output laser diode and a CMOS camera. The irradiated light power distribution was highly uniform with a maximum optical density of 1.3 W/cm2. A 0.3-mmdiameter wooden stick covered with a 2-mm-thick layer of ham can easily be distinguished in the images. The bones in fish and in chicken wing sticks could also be distinguished. The thicknesses of the fish and the chicken wing sticks were approximately 30 mm and 20 mm, respectively. We eliminated the low spatial frequency components from the images to improve the image contrast.

  2. Miniature fuel cell with monolithically fabricated Si electrodes - Uniformity of Catalyst Layer Thickness -

    NASA Astrophysics Data System (ADS)

    Morisawa, Itsuki; Suzuki, Takahiro; Katayama, Noboru; Dowaki, Kiyoshi; Hayase, Masanori

    2014-11-01

    Uniformity of catalyst layer thickness was improved to obtained higher output with our miniature fuel cells. Though the miniature fuel cells demonstrated high power density about 500mW/cm2 with 1 mm2 reaction area, it was difficult to maintain the power density with larger reaction area and careful observation of the prototypes revealed that the porous Si layer, which should be etched away completely, remained on the channel bottoms. Nonuniform porous Pt catalyst layer thickness was suspicious for the residual porous Si, and rotation of the plating vessel in the Pt deposition process was performed to mitigate variation of the catalyst layer thickness. Though the power density was still low with larger reaction area, the larger output was successfully obtained with the vessel rotation.

  3. Shape from equal thickness contours

    SciTech Connect

    Cong, G.; Parvin, B.

    1998-05-10

    A unique imaging modality based on Equal Thickness Contours (ETC) has introduced a new opportunity for 3D shape reconstruction from multiple views. We present a computational framework for representing each view of an object in terms of its object thickness, and then integrating these representations into a 3D surface by algebraic reconstruction. The object thickness is inferred by grouping curve segments that correspond to points of second derivative maxima. At each step of the process, we use some form of regularization to ensure closeness to the original features, as well as neighborhood continuity. We apply our approach to images of a sub-micron crystal structure obtained through a holographic process.

  4. Laser detection of material thickness

    DOEpatents

    Early, James W.

    2002-01-01

    There is provided a method for measuring material thickness comprising: (a) contacting a surface of a material to be measured with a high intensity short duration laser pulse at a light wavelength which heats the area of contact with the material, thereby creating an acoustical pulse within the material: (b) timing the intervals between deflections in the contacted surface caused by the reverberation of acoustical pulses between the contacted surface and the opposite surface of the material: and (c) determining the thickness of the material by calculating the proportion of the thickness of the material to the measured time intervals between deflections of the contacted surface.

  5. A Digital Stereomicroscopic Study of the Radicular Wall Thickness of Two-Canal Mandibular Incisors

    PubMed Central

    Khedmat, Sedigheh; Mohamadian, Sohayla; Kharrazifard, Mohamad Javad

    2015-01-01

    Objectives: This study aimed to assess the radicular wall thickness in mandibular incisors with two canals and find the maximum and minimum thickness to prevent root canal treatment (RCT) procedural errors. Materials and Methods: A total of 160 extracted mandibular incisors were selected and radiographed; out of which, 55 had two canals. Three parallel transverse sections were made in each tooth at 1mm below the cementoenamel junction (CEJ), mid-root and 1 millimeter to the apex. Specimens were evaluated under a stereomicroscope and the thickness of radicular walls in each section was determined for the buccal, lingual and proximal surfaces. Data were statistically analyzed using Pearson’s correlation coefficient test. Results: The thickness of radicular wall decreased from the cervical towards the apex. In all three sections (cervical, mid-root and apical), the thickness of lingual wall was significantly greater than the buccal wall. Also, the thickness of buccal and lingual walls was significantly higher than that of the proximal walls. Conclusion: The lingual radicular wall had the highest thickness in two-canal mandibular incisors. Therefore, in these teeth, the lingual canal is a better choice for post placement. PMID:26877738

  6. Wrong melanoma thickness measurement: check it or leave it?

    PubMed

    Chokoeva, A A; Tchernev, G; Philipov, S; Cardoso, J C; Zanardelli, M; Lotti, T

    2014-01-01

    Cutaneous malignant melanoma (CMM) is one of the most aggressive forms of skin cancer, accounting for about 90% of deaths from cutaneous neoplasms, and its incidence has increased significantly in recent years. According to the 2012 European criteria for diagnosis and treatment of malignant melanoma, diagnosis should be based on the combination of clinical features, dermoscopic data and histological examination, preferably after excisional biopsy. Tumour thickness and other parameters for local staging according to the AJCC classification should be included in the pathology report. Although many factors influence the prognosis and course of the disease, it has been established in a number of studies that tumour thickness is the most important parameter. Therapy of malignant melanoma in its initial stages mostly consists of wide local excision with 1 to 2 cm margins, and sentinel lymph node biopsy that is usually performed in cases of tumours with a thickness greater than 1 mm. We present the case of a 58-year-old Bulgarian male with cutaneous superficial spreading malignant melanoma, in which, after complete excision, histological examination established an inaccurate tumour thickness (0.7 mm), with consequent inadequate staging and further management. After reassessment of the results in another institution (as well as their confirmation by two additional independent histopathology laboratories in our country – 1.92 mm), in the National Oncological Hospital where the patient was initially evaluated, sentinel lymph node biopsy was not performed, contrary to the generally accepted European and World standards. With the present case we raise some current issues regarding diagnosis and therapy of Bulgarian patients (not only in the case presented) with malignant melanoma in the 21st century, and discuss the urgent need for external quality control procedures and standardization of the histopathologic reporting, which is of paramount importance in the staging and

  7. Assessment of immunotoxicity using precision-cut tissue slices

    PubMed Central

    2013-01-01

    1. When the immune system encounters incoming infectious agents, this generally leads to immunity. The evoked immune response is usually robust, but can be severely perturbed by potentially harmful environmental agents such as chemicals, pharmaceuticals and allergens. 2. Immunosuppression, hypersensitivity and autoimmunity may occur due to changed immune activity. Evaluation of the immunotoxic potency of agents as part of risk assessment is currently established in vivo with animal models and in vitro with cell lines or primary cells. 3. Although in vivo testing is usually the most relevant situation for many agents, more and more in vitro models are being developed for assessment of immunotoxicity. In this context, hypersensitivity and immunosuppression are considered to be a primary focus for developing in vitro methods. Three-dimensional organotypic tissue models are also part of current research in immunotoxicology. 4. In recent years, there has been a revival of interest in organotypic tissue models. In the context of immunotoxicity testing, precision-cut lung slices in particular have been intensively studied. Therefore, this review is very much focused on pulmonary immunotoxicology. Respiratory hypersensitivity and inflammation are further highlighted aspects of this review. Immunotoxicity assessment currently is of limited use in other tissue models, which are therefore described only briefly within this review. PMID:23199366

  8. Microglial polarization and plasticity: evidence from organotypic hippocampal slice cultures.

    PubMed

    Ajmone-Cat, Maria Antonietta; Mancini, Melissa; De Simone, Roberta; Cilli, Piera; Minghetti, Luisa

    2013-10-01

    Increasing evidence indicates that "functional plasticity" is not solely a neuronal attribute but a hallmark of microglial cells, the main brain resident macrophage population. Far from being a univocal phenomenon, microglial activation can originate a plethora of functional phenotypes, encompassing the classic M1 proinflammatory and the alternative M2 anti-inflammatory phenotypes. This concept overturns the popular view of microglial activation as a synonym of neurotoxicity and neurogenesis failure in brain disorders. The characterization of the alternative programs is a matter of intense investigation, but still scarce information is available on the course of microglial activation, on the reversibility of the different commitments and on the capability of preserving molecular memory of previous priming stimuli. By using organotypic hippocampal slice cultures as a model, we developed paradigms of stimulation aimed at shedding light on some of these aspects. We show that persistent stimulation of TLR4 signaling promotes an anti-inflammatory response and microglial polarization toward M2-like phenotype. Moreover, acute and chronic preconditioning regimens permanently affect the capability to respond to a later challenge, suggesting the onset of mechanisms of molecular memory. Similar phenomena could occur in the intact brain and differently affect the vulnerability of mature and newborn neurons to noxious signals. PMID:23918452

  9. Fully programmable spectrum sliced chirped microwave photonic filter.

    PubMed

    Leitner, Peter; Yi, Xiaoke; Li, Liwei; Huang, Thomas X H

    2015-02-23

    A novel chirped microwave photonic filter (MPF) capable of achieving a large radio frequency (RF) group delay slope and a single passband response free from high frequency fading is presented. The design is based upon a Fourier domain optical processor (FD-OP) and a single sideband modulator. The FD-OP is utilized to generate both constant time delay to tune the filter and first order dispersion to induce the RF chirp, enabling full software control of the MPF without the need for manual adjustment. An optimized optical parameter region based on a large optical bandwidth >750 GHz and low slicing dispersion < ± 1 ps/nm is introduced, with this technique greatly improving the RF properties including the group delay slope magnitude and passband noise. Experimental results confirm that the structure simultaneously achieves a large in-band RF chirp of -4.2 ns/GHz, centre frequency invariant tuning and independent reconfiguration of the RF amplitude and phase response. Finally, a stochastic study of the device passband noise performance under tuning and reconfiguration is presented, indicating a low passband noise <-120 dB/Hz. PMID:25836442

  10. Spectral decomposition of black-hole perturbations on hyperboloidal slices

    NASA Astrophysics Data System (ADS)

    Ansorg, Marcus; Macedo, Rodrigo Panosso

    2016-06-01

    In this paper, we present a spectral decomposition of solutions to relativistic wave equations described on horizon-penetrating hyperboloidal slices within a given Schwarzschild-black-hole background. The wave equation in question is Laplace transformed, which leads to a spatial differential equation with a complex parameter. For initial data which are analytic with respect to a compactified spatial coordinate, this equation is treated with the help of the Mathematica package in terms of a sophisticated Taylor series analysis. Thereby, all ingredients of the desired spectral decomposition arise explicitly to arbitrarily prescribed accuracy, including quasinormal modes and quasinormal mode amplitudes as well as the jump of the Laplace transform along the branch cut. Finally, all contributions are put together to obtain, via the inverse Laplace transformation, the spectral decomposition in question. The paper explains extensively this procedure and includes detailed discussions of relevant aspects, such as the definition of quasinormal modes and the question regarding the contribution of infinity frequency modes to the early time response of the black hole.

  11. Fiber optic biofluorometer for physiological research on muscle slices

    NASA Astrophysics Data System (ADS)

    Belz, Mathias; Dendorfer, Andreas; Werner, Jan; Lambertz, Daniel; Klein, Karl-Friedrich

    2016-03-01

    A focus of research in cell physiology is the detection of Ca2+, NADH, FAD, ATPase activity or membrane potential, only to name a few, in muscle tissues. In this work, we report on a biofluorometer using ultraviolet light emitting diodes (UV-LEDs), optical fibers and two photomultipliers (PMTs) using synchronized fluorescence detection with integrated background correction to detect free calcium, Ca2+, in cardiac muscle tissue placed in a horizontal tissue bath and a microscope setup. Fiber optic probes with imaging optics have been designed to transport excitation light from the biofluorometer's light output to a horizontal tissue bath and to collect emission light from a tissue sample of interest to two PMTs allowing either single excitation / single emission or ratiometric, dual excitation / single emission or single excitation / dual emission fluorescence detection of indicator dyes or natural fluorophores. The efficient transport of light from the excitation LEDs to the tissue sample, bleaching effects of the excitation light in both, polymer and fused silica-based fibers will be discussed. Furthermore, a new approach to maximize light collection of the emission light using high NA fibers and high NA coupling optics will be shown. Finally, first results on Ca2+ measurements in cardiac muscle slices in a traditional microscope setup and a horizontal tissue bath using fiber optic probes will be introduced and discussed.

  12. Compact Image Slicing Spectrometer (ISS) for hyperspectral fluorescence microscopy

    PubMed Central

    Gao, Liang; Kester, Robert T.; Tkaczyk, Tomasz S.

    2009-01-01

    An image slicing spectrometer (ISS) for microscopy applications is presented. Its principle is based on the redirecting of image zones by specially organized thin mirrors within a custom fabricated component termed an image slicer. The demonstrated prototype can simultaneously acquire a 140nm spectral range within its 2D field of view from a single image. The spectral resolution of the system is 5.6nm. The FOV and spatial resolution of the ISS depend on the selected microscope objective and for the results presented is 45×45μm2 and 0.45μm respectively. This proof-of-concept system can be easily improved in the future for higher (both spectral and spatial) resolution imaging. The system requires no scanning and minimal post data processing. In addition, the reflective nature of the image slicer and use of prisms for spectral dispersion make the system light efficient. Both of the above features are highly valuable for real time fluorescent-spectral imaging in biological and diagnostic applications. PMID:19654631

  13. Initial data for perturbed Kerr black holes on hyperboloidal slices

    NASA Astrophysics Data System (ADS)

    Schinkel, David; Panosso Macedo, Rodrigo; Ansorg, Marcus

    2014-08-01

    We construct initial data corresponding to a single perturbed Kerr black hole in vacuum. These data are defined on specific hyperboloidal (ACMC) slices, on which the mean extrinsic curvature K asymptotically approaches a constant at future null infinity {{\\mathscr{I}}^{+}}. More precisely, we require that K obeys the Taylor expansion K={{K}_{0}}+O\\left( {{\\sigma }^{4}} \\right), where {{K}_{0}} is a constant and σ describes a compactified spatial coordinate such that {{\\mathscr{I}}^{+}} is represented by \\sigma =0. We excise the singular interior of the black hole and assume a marginally outer trapped surface as the inner boundary of the computational domain. The momentum and Hamiltonian constraints are solved by means of pseudo-spectral methods and we find exponential rates of convergence of our numerical solutions. Some of the physical properties of the initial data are studied with the calculation of the Bondi mass, together with a multipole decomposition of the horizon. We probe the standard picture of gravitational collapse by assessing a family of Penrose-like inequalities and discuss in particular their rigidity aspects. Dynamical evolutions are planned in a future project.

  14. Improved Coal-Thickness Measurement

    NASA Technical Reports Server (NTRS)

    Barr, T. A.

    1984-01-01

    Summed signals and dielectric-filled antenna improve measurement. Improved FM radar for measuring thickness of coal seam eliminates spectrum splitting and reduces magnitude of echo from front coal surface.

  15. Metal thickness measurements using radiography

    NASA Astrophysics Data System (ADS)

    Achrekar, P. M.

    1986-04-01

    The present invention relates broadly to a radiographic inspection technique, and in particular to a metal thickness measurement method using radiography. The localized areas wherein the effective metal thickness is less than the minimum that is required for radiation shielding and which can render a shielding enclosure functionless, is readily determined. The invention comprises a process for assuring metal thickness in small regions. The actual metal thickness of small regions can be verified by comparing the optical densities of sections of the metal i.e., stepwedge. A comparator microphotometer, which compares optical densities of spectrum lines from spectrophotometers, compares the optical density of spectrum lines on an exposed spectrum plate (metal under test) with a standard plate (stepwedge).

  16. Edge-on thick discs

    NASA Astrophysics Data System (ADS)

    Kasparova, A.; Katkov, I.; Chilingarian, I.; Silchenko, O.; Moiseev, A.; Borisov, S.

    2016-06-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on early-type disc galaxies located in different environments: NGC4111 in a dense group, NGC4710 in the Virgo cluster, and NGC5422 in a sparse group. We see intermediate age (4 ‑ 5 Gyr) metal rich ([Fe/H] ~ ‑0.2 ‑ 0.0 dex) stellar populations in NGC4111 and NGC4710. On the other hand, NGC5422 does not harbour young stars, its only disc is thick and old (10 Gyr) and its α-element abundance suggests a long formation epoch implying its formation at high redshift. Our results prove the diversity of thick disc formation scenarios.

  17. Factors Affecting Crown Gall Tumorigenesis in Tuber Slices of Jerusalem Artichoke (Helianthus tuberosus, L.) 1

    PubMed Central

    Tanimoto, Eugene; Douglas, Carl; Halperin, Walter

    1979-01-01

    Agrobacterium tumefaciens can induce tumors on thin slices which are excised from Jerusalem artichoke (Helianthus tuberosus) tubers and grown in culture on medium containing minerals and a carbon source. A comparative study was made of the kinetics of cell division in slices under three conditions: (a) slices which were untreated and showed only spontaneous (wound-induced) cell divisions; (b) slices treated with indoleacetic acid at several concentrations; and (c) slices treated with virulent or avirulent bacteria. The earliest spontaneous cell divisions were completed (as detected by the appearance of new daughter cell pairs) by about 3 hours. These cells divide only once. In indoleacetic acid-treated tissue, more cells divide, with the first cell pairs being detected slightly earlier than in slices not subjected to the hormone. The number of cells which divide is roughly proportional to auxin concentration. Tissue treated with virulent bacteria showed only the pattern of spontaneous cell division until about 72 hours, after which another burst of cell division commenced and continued indefinitely. The bacteria-induced growths produced the unusual amino acids which are characteristic of crown gall tumors. The percentage of slices with tumors was sharply reduced if certain avirulent A. tumefaciens strains were applied prior to virulent strains. Images PMID:16660891

  18. Slicing of silicon ingots with reduced kerf. Final report (Phase II)

    SciTech Connect

    Schmid, F.; Smith, M.; Schmid, K.; Khattak, C.P.

    2001-01-04

    The Fixed Abrasive Slicing Technique (FAST) has been developed as an effective wafering technique by combining the advantages of diamond as an abrasive like internal diamond (ID), a reciprocating bladehead as in Multi-Blade Slurry (MBS) and wire slicing as in multiwire slicing (MWS) techniques. During the development stage, it was necessary to develop a slicer, bladepacks and the technique. It was recognized that high pressures were required between the diamond abrasive and the crystal to achieve effective slicing. This was achieved by rocking the workpiece to minimize the contact length. During the present work, the cutting effectiveness was enhanced by increasing the rotary speed of the crystal in the range of 2,500 to 5,000 rpm and the reciprocating rate of the bladehead to about 100 cycles/minute. The combination of high speed rotation of the crystal and FAST slicing have produced more effective slicing by increasing the cutting rate by a factor of 50 to produce multiple wafers wit h low kerf, low surface damage and high accuracy. In addition, this technique is now applicable for soft as well as very hard crystals. Based on these developments, Crystal Systems is currently commercializing FAST for slicing of a wide variety of hard and soft crystals.

  19. Lysosome stabilization in slices of rat liver when incubated with vitamin A excess

    SciTech Connect

    Morre, D.M.; Morre, D.J.; Bowen, S.; Reutter, W.

    1986-05-01

    An organ culture of slices of livers from adult rats was used to study effect of vitamin A (all-trans retinol) on lysosome stability. Lysosomes were purified by centrifugation in Percoll gradients. Preparations were monitored by electron microscopy and evaluated by morphometry and assays of marker enzymes. Enrichments relative to homogenates and crude pellets were estimated from latent (triton X-100) acid p-nitrophenylphosphatase specific activities. Lysosomes prepared from unincubated slices were enriched 50-fold in latent acid phosphatase relative to homogenates. In contrast, lysosomes prepared from slices incubated for 30 min in PBS alone were enriched only 20-fold. When 25 ..mu..g/ml retinol was included in the incubation medium, enrichments of 40-fold were obtained. The integrity of the slices was monitored by electron microscopy and their viability was confirmed by a sustained uptake and incorporation of (/sup 3/H)leucine into protein (up to 2 h in culture). The loss of lysosomes from homogenates of slices incubated in the absence of retinol was accompanied by a loss of acid phosphatase from the lysosomal pellet to the supernatant during purification. Addition of retinol to slices just prior to homogenization was without effect. The results demonstrate a stabilizing influence of vitamin A on lysosomes during incubation of licer slices. The findings contrast earlier reports of retinol-induced lysosome fragility in other in vitro systems.

  20. Peripapillary choroidal thickness in childhood.

    PubMed

    Read, Scott A; Alonso-Caneiro, David; Vincent, Stephen J; Collins, Michael J

    2015-06-01

    Changes in the thickness of the invivo peripapillary choroid have been documented in a range of ocular conditions in adults; however, choroidal thickness in the peripapillary region of children has not been examined in detail. This study therefore aimed to investigate the thickness of the peripapillary choroid and the overlying retinal nerve fibre layer (RNFL) in a population of normal children with a range of refractive errors. Ninety-three children (37 myopes and 56 non-myopes) aged between 11 and 16 years, had measurements of peripapillary choroidal and RNFL thickness derived from enhanced depth imaging optical coherence tomography images (EDI-OCT, Heidelberg Spectralis). The average thickness was determined in a series of five 0.25 mm width concentric annuli (each divided into 8 equal sized 45° sectors) centred on the optic nerve head boundary, accounting for individual ocular magnification factors and the disc-fovea angle. Significant variations in peripapillary choroidal thickness were found to occur with both annulus location (p < 0.001) and sector position (p < 0.001) in this population of children. The innermost annulus (closest to the edge of the optic disc) exhibited the thinnest choroid (mean 77 ± 16 μm) and the outermost annulus, the thickest choroid (191 ± 52 μm). The choroid was thinnest inferior to the optic nerve head (139 ± 38 μm) and was thickest in the superior temporal sector (157 ± 40 μm). Significant differences in the distribution of choroidal thickness were also associated with myopia, with myopic children having significantly thinner choroids in the inner and outer annuli of the nasal and temporal sectors respectively (p < 0.001). RNFL thickness also varied significantly with annulus location and sector (p < 0.001), and showed differences in thickness distribution associated with refractive error. This study establishes the normal variations in the thickness of the peripapillary choroid with radial distance and azimuthal angle

  1. The relation of gingival thickness to dynamics of gingival margin position pre- and post-surgically

    PubMed Central

    Vandana, Kharidhi Laxman; Gupta, Ira

    2016-01-01

    Background: To evaluate the gingival margin position (GMP) before and after open flap debridement in different gingival thickness (GT). Materials and Methods: Twenty-seven healthy patients with moderate to advanced adult periodontitis were included in a randomized control clinical trial. A calibrated UNC-15 periodontal probe, an occlusal onlay stent was used for clinical measurements recorded at baseline, 3 month, 6 month, and 16 month. The changes in the GMP were studied at midbuccal (Mi-B), mesiobuccal (MB), and distobuccal sites. GT was measured presurgically, transgingivally at Mi-B and interdental sites, divided into 2 groups: Group 1 (thin) and Group 2 (thick). Results: In GT of ≤1 mm group, the statistically significant apical shift of GMP led to gingival recession at all study sites in the early postsurgical period of 1 and 3 months. During 6 and 16 months, the apical shift of GMP coincided with the Chernihiv Airport at Mi-B site (6 months), MB site (16 months). The gingival recession was obvious at Mi-B sites (16 months). In the GT of >1 mm, the statistically significant apical shift of GMP did not cause gingival recession at any sites throughout postsurgical (1, 3, 6, and 16 months) period. Conclusion: Thin gingiva showed apical shift of GMP leading to gingival recession as compared to thick gingiva postsurgically. PMID:27143829

  2. Modification of hippocampal excitability in brain slices pretreated with a low nanomolar concentration of Zn2+.

    PubMed

    Takeda, Atsushi; Shakushi, Yukina; Tamano, Haruna

    2015-11-01

    Synaptic Zn2+ homeostasis may be changed during brain slice preparation. However, much less attention has been paid to Zn2+ in artificial cerebrospinal fluid (ACSF) used for slice experiments than has been paid to Ca2+ . The present study assesses addition of Zn2+ to ACSF, focused on hippocampal excitability after acute brain slice preparation. When the static levels of intracellular Zn2+ and Ca2+ were compared between brain slices prepared with conventional ACSF without Zn2+ and those pretreated with ACSF containing 20 nM ZnCl2 for 1 hr, both levels were almost the same. On the other hand, intracellular Ca2+ levels were significantly increased in the stratum lucidum of the control brain slices after stimulation with high K+, although the increase was significantly suppressed by the pretreatment with ACSF containing Zn2+, suggesting that neuronal excitation is enhanced in brain slices prepared with ACSF without Zn2+. The increase in extracellular Zn2+ level, an index of glutamate release, after stimulation with high K+ was also significantly suppressed by pretreatment with ACSF containing Zn2+. When mossy fiber excitation was assessed in brain slices with FM4-64, an indicator of presynaptic activity, attenuation of FM 4-64 fluorescence based on presynaptic activity was suppressed in the stratum lucidum of brain slices pretreated with ACSF containing Zn2+. The present study indicates that hippocampal excitability is enhanced in brain slices prepared with ACSF without Zn2+. It is likely that a low nanomolar concentration of Zn2+ is necessary for ACSF. PMID:26268632

  3. A multi-slice recording system for stable late phase hippocampal long-term potentiation experiments.

    PubMed

    Kroker, Katja Sabine; Rosenbrock, Holger; Rast, Georg

    2011-01-15

    A major challenge in neuroscience is identifying the cellular and molecular processes underlying learning and memory formation. In the past decades, significant progress has been made in understanding cellular and synaptic mechanisms underlying hippocampal learning and memory using long-term potentiation (LTP) experiments in brain slices as a model system. To expedite LTP measurements it is helpful to further optimize such recording systems. Here, we describe a modification of a multi-slice recording system (SliceMaster, Scientifica Limited, East Sussex, UK) that allows absolutely stable measurements of field excitatory postsynaptic potentials (fEPSPs) for up to 8 h in up to eight slices simultaneously. The software Notocord(®) was used for on-line data acquisition and to control the digital pattern generator which can generate different patterns for slice stimulation, inducing different types of LTP. Moreover, in contrast to common gravity-driven perfusion systems, a Pumped Perfusion System was employed to recycle drug solutions applied to the hippocampal slice. In addition, slices were positioned on two stacked grids for optimal recording of fEPSPs. These two stacked grids were placed in the measuring chambers allowing recordings for several hours without any perturbances. In summary, this modified slice-recording system improves throughput and allows for better statistical design, increases number of used slices per animal and enables very robust LTP measurements for up to 7 h. Hence, this system is suitable not only to investigate molecular mechanisms underlying the late phase of LTP, but also to screen candidate compounds in the context of drug discovery. PMID:21087635

  4. Localization of beta-adrenergic receptors in transmural slices of myocardium with quantitative autoradiography

    SciTech Connect

    Murphree, S.S.; Saffitz, J.E.

    1986-03-01

    Alterations in the density of myocardial ..beta..-adrenergic receptors (..beta..AR) induced by ischemia may be important in the pathophysiology of acute ischemic heart disease. Conventional binding assays in tissue homogenates lack the anatomic resolution required for cell-specific analysis of early alterations in receptor density induced by ischemia. Accordingly, the authors have developed methods for localization of ..beta..AR in transmural slices of feline left ventricle with quantitative autoradiography. Frozen sections were incubated with /sup 125/I-iodocyanopindolol (ICYP) +/- Z-propranolol for 60 min at 37/sup 0/. Non-specifically bound radioactivity was removed by rinsing the sections for 60 min at 22/sup 0/. At saturating concentrations of ICYP, > 90% specific binding was achieved. Specific binding was rapid, saturable, of high affinity and proportional to section thickness (B/sub max/ = 26.5 +/- 6.4 fmol/mg tissue protein; K/sub d/ = 10.0 +/- 2.1 pM; N = 14). Agonist binding showed the rank order of potency expected for ..beta..AR (IC/sub 50/ = 0.12 ..mu..M, isoproterenol; .18 ..mu..M, norepinephrine; .54 ..mu..M, epinephrine) and demonstrated stereo-selectivity (IC/sub 50/ = .013 ..mu..M, Z-isoproterenol; 9.5 ..mu..M, d-isoproterenol). Quantitative autoradiography with both film and emulsion methods will permit regional analysis of ..beta..AR density in large transmural sections as well as cell-specific analysis at the microscopic level.

  5. THz emission from a slice of high-Tc superconducting single crystal

    NASA Astrophysics Data System (ADS)

    Wang, Huabing

    2008-03-01

    Copper oxide superconductors possess intrinsically a layered crystalline structure, in which superconducting and non-superconducting layers interleave each other. Therefore the crystal itself consists of a number of superconducting junctions sequentially stacked along the c axis of the crystal, and these junctions are often referred to as intrinsic Josephson junctions (IJJs). In the case of Bi2Sr2CaCu2O8+δ (BSCCO), each IJJ measures approximately 1.5 nm thick. Many groups have been exploring the possibilities to develop terahertz (THz) detectors and oscillators based on IJJs, due to the high collective plasma frequencies (up to THz region), the uniformity in junction properties, the easiness to make a large junction array, and the low loss at high frequencies. Some years ago, in IJJs singled out from inside a slice of BSCCO single crystal with a double-sided process, THz response was successfully observed as sharp Shapiro steps at frequencies up to 2.5 THz, and harmonic mixings were carried out with harmonic numbers as large as 90. Recently observed have been THz oscillations in various structures of BSCCO IJJs, which can be excited by dc bias, in-plane magnetic fields, or microwave irradiations at several gigahertz. Needless to say, for practical applications, it is necessary to synchronize the emissions from IJJs, couple the THz oscillations into a finite space, guide them in a controllable way, monitor the frequencies and power levels, and preferably do the jobs using an integrated system. We have been making extensive efforts to explore these ideas, and will report our latest results at the meeting.

  6. Use of B-mode ultrasonography for measuring femoral muscle thickness in dogs.

    PubMed

    Sakaeda, Kanako; Shimizu, Miki

    2016-06-01

    Assessment of muscle mass is important for evaluating muscle function and rehabilitation outcomes. Ultrasound has recently been successfully used to estimate muscle mass in humans by measuring muscle thickness. This study attempted to standardize procedures for measuring femoral muscle thickness ultrasonographically, as well as quantify the reliability and validity of ultrasound evaluations of muscle thickness compared to measurements made by magnetic resonance imaging (MRI) in dogs. We evaluated the quadriceps femoris (QF), biceps femoris (BF), semitendinosus (ST) and semimembranosus (SM) muscles of 10 clinically healthy Beagle dogs. Scans were taken in 5 different sections divided equally between the greater trochanter and proximal patella. MRI was performed, followed by T1-weighted and contrast-enhanced T1-weighted imaging. Muscle cross-sectional area (CSA) was measured with MRI, and muscle thickness was measured with MRI and ultrasonography. The thickness of the QF, BF and ST muscles as measured by ultrasound at slices 1-3 (from the proximal end to the middle of the femur), 2-4 (middle of the femur) and 2 (more proximal than the middle of the femur), respectively, was correlated with muscle thickness and CSA as measured by MRI. These sites showed a flat interface between muscle and transducer and were situated over belly muscle. No correlation between measurement types was seen in SM muscle. We must confirm this assessment method for various breeds, sizes, ages and muscle pathologies in dogs, thereby confirming that muscle thickness as measured ultrasonographically can reflect muscle function. PMID:26832997

  7. Use of B-mode ultrasonography for measuring femoral muscle thickness in dogs

    PubMed Central

    SAKAEDA, Kanako; SHIMIZU, Miki

    2016-01-01

    Assessment of muscle mass is important for evaluating muscle function and rehabilitation outcomes. Ultrasound has recently been successfully used to estimate muscle mass in humans by measuring muscle thickness. This study attempted to standardize procedures for measuring femoral muscle thickness ultrasonographically, as well as quantify the reliability and validity of ultrasound evaluations of muscle thickness compared to measurements made by magnetic resonance imaging (MRI) in dogs. We evaluated the quadriceps femoris (QF), biceps femoris (BF), semitendinosus (ST) and semimembranosus (SM) muscles of 10 clinically healthy Beagle dogs. Scans were taken in 5 different sections divided equally between the greater trochanter and proximal patella. MRI was performed, followed by T1-weighted and contrast-enhanced T1-weighted imaging. Muscle cross-sectional area (CSA) was measured with MRI, and muscle thickness was measured with MRI and ultrasonography. The thickness of the QF, BF and ST muscles as measured by ultrasound at slices 1–3 (from the proximal end to the middle of the femur), 2–4 (middle of the femur) and 2 (more proximal than the middle of the femur), respectively, was correlated with muscle thickness and CSA as measured by MRI. These sites showed a flat interface between muscle and transducer and were situated over belly muscle. No correlation between measurement types was seen in SM muscle. We must confirm this assessment method for various breeds, sizes, ages and muscle pathologies in dogs, thereby confirming that muscle thickness as measured ultrasonographically can reflect muscle function. PMID:26832997

  8. Algorithms for muscle oxygenation monitoring corrected for adipose tissue thickness

    NASA Astrophysics Data System (ADS)

    Geraskin, Dmitri; Platen, Petra; Franke, Julia; Kohl-Bareis, Matthias

    2007-07-01

    The measurement of skeletal muscle oxygenation by NIRS methods is obstructed by the subcutaneous adipose tissue which might vary between < 1 mm to more than 12 mm in thickness. A new algorithm is developed to minimize the large scattering effect of this lipid layer on the calculation of muscle haemoglobin / myoglobin concentrations. First, we demonstrate by comparison with ultrasound imaging that the optical lipid signal peaking at 930 nm is a good predictor of the adipose tissue thickness (ATT). Second, the algorithm is based on measurements of the wavelength dependence of the slope ΔA/Δρ of attenuation A with respect to source detector distance ρ and Monte Carlo simulations which estimate the muscle absorption coefficient based on this slope and the additional information of the ATT. Third, we illustrate the influence of the wavelength dependent transport scattering coefficient of the new algorithm by using the solution of the diffusion equation for a two-layered turbid medium. This method is tested on experimental data measured on the vastus lateralis muscle of volunteers during an incremental cycling exercise under normal and hypoxic conditions (corresponding to 0, 2000 and 4000 m altitude). The experimental setup uses broad band detection between 700 and 1000 nm at six source-detector distances. We demonstrate that the description of the experimental data as judged by the residual spectrum is significantly improved and the calculated changes in oxygen saturation are markedly different when the ATT correction is included.

  9. Slice emittance measurement for photocathode RF gun with solenoid scanning and RF deflecting cavity

    NASA Astrophysics Data System (ADS)

    Li, Chen; Huang, WenHui; Du, YingChao; Yan, LiXin; Tang, ChuanXiang

    2011-12-01

    The radiation of high-gain short-wavelength free-electron laser depends on the slice transverse emittance of the electron bunch. This essay introduces the method of slice emittance measurement, and shows the brief setup of this experiment using the solenoid scanning and RF deflecting cavity at Tsinghua University. The preliminary experimental results show that the slice rms emittance of the electron bunch generated by photocathode RF gun has considerable variations along the bunch and is typically less than 0.55 mm mrad for the laser rms radius of 0.4 mm.

  10. Long-term potentiation in the hippocampal slice: evidence for stimulated secretion of newly synthesized proteins

    SciTech Connect

    Duffy, C.; Teyler, T.J.; Shashoua, V.E.

    1981-06-01

    Long-term potentiation of the hippocampal slice preparation results in an increase in the incorporation of labeled valine into the proteins destined for secretion into the extracellular medium. Double-labeling methods established that the increased secretion of the labeled proteins was limited to the potentiated region of a slice; incorporation of labeled valine was increased in the hippocampus if potentiation was through the Schaffer collaterals and in the dentate if potentiation was through the perforant path. Controls for nonspecific stimulation showed no changes. There appears to be a link between long-term potentiation and the metabolic processes that lead to protein synthesis in the hippocampal slice system.

  11. Slice-Based Formal Specification Measures -- Mapping Coupling and Cohesion Measures to Formal Z

    NASA Technical Reports Server (NTRS)

    Bollin, Andreas

    2010-01-01

    This paper demonstrates that existing slice-based measures can reasonably be mapped to the field of state-based specification languages. By making use of Z specifications this contribution renews the idea of slice-profiles and derives coupling and cohesion measures for them. The measures are then assessed by taking a critical look at their sensitiveness in respect to modifications on the specification source. The presented study shows that slice-based coupling and cohesion measures have the potential to be used as quality indicators for specifications as they reflect the changes in the structure of a specification as accustomed from their program-related pendants.

  12. Development of a fixed abrasive slicing technique (FAST) for reducing the cost of photovoltaic wafers

    SciTech Connect

    Schmid, F. )

    1991-12-01

    This report examines a wafer slicing technique developed by Crystal Systems, Inc. that reduces the cost of photovoltaic wafers. This fixed, abrasive slicing technique (FAST) uses a multiwire bladepack and a diamond-plated wirepack; water is the coolant. FAST is in the prototype production stage and reduces expendable material costs while retaining the advantages of a multiwire slurry technique. The cost analysis revealed that costs can be decreased by making more cuts per bladepack and slicing more wafers per linear inch. Researchers studied the degradation of bladepacks and increased wirepack life. 21 refs.

  13. The luminosity function for the CfA redshift survey slices

    NASA Technical Reports Server (NTRS)

    De Lapparent, Valerie; Geller, Margaret J.; Huchra, John P.

    1989-01-01

    The luminosity function for two complete slices of the extension of the CfA redshift survey is calculated. The nonparametric technique of Lynden-Bell (1971) and Turner (1979) is used to determine the shape for the luminosity function of the 12 deg slice of the redshift survey. The amplitude of the luminosity function is determined, taking large-scale inhomogeneities into account. The effects of the Malmquist bias on a magnitude-limited redshift survey are examined, showing that the random errors in the magnitudes for the 12 deg slice affect both the determination of the luminosity function and the spatial density constrast of large scale structures.

  14. Increasing the range accuracy of three-dimensional ghost imaging ladar using optimum slicing number method

    NASA Astrophysics Data System (ADS)

    Yang, Xu; Zhang, Yong; Xu, Lu; Yang, Cheng-Hua; Wang, Qiang; Liu, Yue-Hao; Zhao, Yuan

    2015-12-01

    The range accuracy of three-dimensional (3D) ghost imaging is derived. Based on the derived range accuracy equation, the relationship between the slicing number and the range accuracy is analyzed and an optimum slicing number (OSN) is determined. According to the OSN, an improved 3D ghost imaging algorithm is proposed to increase the range accuracy. Experimental results indicate that the slicing number can affect the range accuracy significantly and the highest range accuracy can be achieved if the 3D ghost imaging system works with OSN. Project supported by the Young Scientist Fund of the National Natural Science Foundation of China (Grant No. 61108072).

  15. Organotypic slice co-culture systems to study axon regeneration in the dopaminergic system ex vivo.

    PubMed

    Heine, Claudia; Franke, Heike

    2014-01-01

    Organotypic slice co-cultures are suitable tools to study axonal regeneration and development (growth or regrowth) of different projection systems of the CNS under ex vivo conditions.In this chapter, we describe in detail the reconstruction of the mesocortical and nigrostriatal dopaminergic projection system culturing tissue slices from the ventral tegmental area/substantia nigra (VTA/SN) with the prefrontal cortex (PFC) or the striatum (STR). The protocol includes the detailed slice preparation and incubation. Moreover, different application possibilities of the ex vivo model are mentioned; as an example, the substance treatment procedure and biocytin tracing are described to reveal the effect of applied substances on fiber outgrowth. PMID:24838961

  16. Computerized method for automated measurement of thickness of cerebral cortex for 3-D MR images

    NASA Astrophysics Data System (ADS)

    Arimura, Hidetaka; Yoshiura, Takashi; Kumazawa, Seiji; Koga, Hiroshi; Sakai, Shuji; Mihara, Futoshi; Honda, Hiroshi; Ohki, Masafumi; Toyofuku, Fukai; Higashida, Yoshiharu

    2006-03-01

    Alzheimer's disease (AD) is associated with the degeneration of cerebral cortex, which results in focal volume change or thinning in the cerebral cortex in magnetic resonance imaging (MRI). Therefore, the measurement of the cortical thickness is important for detection of the atrophy related to AD. Our purpose was to develop a computerized method for automated measurement of the cortical thickness for three-dimensional (3-D) MRI. The cortical thickness was measured with normal vectors from white matter surface to cortical gray matter surface on a voxel-by-voxel basis. First, a head region was segmented by use of an automatic thresholding technique, and then the head region was separated into the cranium region and brain region by means of a multiple gray level thresholding with monitoring the ratio of the first maximum volume to the second one. Next, a fine white matter region was determined based on a level set method as a seed region of the rough white matter region extracted from the brain region. Finally, the cortical thickness was measured by extending normal vectors from the white matter surface to gray matter surface (brain surface) on a voxel-by-voxel basis. We applied the computerized method to high-resolution 3-D T1-weighted images of the whole brains from 7 clinically diagnosed AD patients and 8 healthy subjects. The average cortical thicknesses in the upper slices for AD patients were thinner than those for non-AD subjects, whereas the average cortical thicknesses in the lower slices for most AD patients were slightly thinner. Our preliminary results suggest that the MRI-based computerized measurement of gray matter atrophy is promising for detecting AD.

  17. Influence of slice overlap on positron emission tomography image quality

    NASA Astrophysics Data System (ADS)

    McKeown, Clare; Gillen, Gerry; Dempsey, Mary Frances; Findlay, Caroline

    2016-02-01

    PET scans use overlapping acquisition beds to correct for reduced sensitivity at bed edges. The optimum overlap size for the General Electric (GE) Discovery 690 has not been established. This study assesses how image quality is affected by slice overlap. Efficacy of 23% overlaps (recommended by GE) and 49% overlaps (maximum possible overlap) were specifically assessed. European Association of Nuclear Medicine (EANM) guidelines for calculating minimum injected activities based on overlap size were also reviewed. A uniform flood phantom was used to assess noise (coefficient of variation, (COV)) and voxel accuracy (activity concentrations, Bq ml-1). A NEMA (National Electrical Manufacturers Association) body phantom with hot/cold spheres in a background activity was used to assess contrast recovery coefficients (CRCs) and signal to noise ratios (SNR). Different overlap sizes and sphere-to-background ratios were assessed. COVs for 49% and 23% overlaps were 9% and 13% respectively. This increased noise was difficult to visualise on the 23% overlap images. Mean voxel activity concentrations were not affected by overlap size. No clinically significant differences in CRCs were observed. However, visibility and SNR of small, low contrast spheres (⩽13 mm diameter, 2:1 sphere to background ratio) may be affected by overlap size in low count studies if they are located in the overlap area. There was minimal detectable influence on image quality in terms of noise, mean activity concentrations or mean CRCs when comparing 23% overlap with 49% overlap. Detectability of small, low contrast lesions may be affected in low count studies—however, this is a worst-case scenario. The marginal benefits of increasing overlap from 23% to 49% are likely to be offset by increased patient scan times. A 23% overlap is therefore appropriate for clinical use. An amendment to EANM guidelines for calculating injected activities is also proposed which better reflects the effect overlap size has

  18. Hemoglobinopathies: slicing the Gordian knot of Plasmodium falciparum malaria pathogenesis.

    PubMed

    Taylor, Steve M; Cerami, Carla; Fairhurst, Rick M

    2013-01-01

    Plasmodium falciparum malaria kills over 500,000 children every year and has been a scourge of humans for millennia. Owing to the co-evolution of humans and P. falciparum parasites, the human genome is imprinted with polymorphisms that not only confer innate resistance to falciparum malaria, but also cause hemoglobinopathies. These genetic traits--including hemoglobin S (HbS), hemoglobin C (HbC), and α-thalassemia--are the most common monogenic human disorders and can confer remarkable degrees of protection from severe, life-threatening falciparum malaria in African children: the risk is reduced 70% by homozygous HbC and 90% by heterozygous HbS (sickle-cell trait). Importantly, this protection is principally present for severe disease and largely absent for P. falciparum infection, suggesting that these hemoglobinopathies specifically neutralize the parasite's in vivo mechanisms of pathogenesis. These hemoglobin variants thus represent a "natural experiment" to identify the cellular and molecular mechanisms by which P. falciparum produces clinical morbidity, which remain partially obscured due to the complexity of interactions between this parasite and its human host. Multiple lines of evidence support a restriction of parasite growth by various hemoglobinopathies, and recent data suggest this phenomenon may result from host microRNA interference with parasite metabolism. Multiple hemoglobinopathies mitigate the pathogenic potential of parasites by interfering with the export of P. falciparum erythrocyte membrane protein 1 (PfEMP1) to the surface of the host red blood cell. Few studies have investigated their effects upon the activation of the innate and adaptive immune systems, although recent murine studies suggest a role for heme oxygenase-1 in protection. Ultimately, the identification of mechanisms of protection and pathogenesis can inform future therapeutics and preventive measures. Hemoglobinopathies slice the "Gordian knot" of host and parasite

  19. Optimization of slice sensitivity profile for radiographic tomosynthesis

    SciTech Connect

    Li Baojun; Avinash, Gopal B.; Eberhard, Jeffrey W.; Claus, Bernhard E. H.

    2007-07-15

    Similar to other tomographic imaging modalities, the slice sensitivity profile (SSP) is an important image quality metric for radiographic tomosynthesis. In this study, the relationship between the acquisition angular range ({theta}) and the SSP for the linear trajectory system was carefully investigated from both theoretical and experimental perspectives. A mathematical SSP model was derived for arbitrary points in the reconstructed volume. We used a newly developed flat-panel tomosynthesis prototype system to experimentally validate the mathematical model from 20 deg. ({+-}10 deg.) to 60 deg. ({+-}30 deg.) angular ranges. The SSP was measured by imaging an edge phantom placed at an angle with respect to the detector plane using the modulation transfer function degradation (MTF-d) method. In addition to the experiments, computer simulations were performed to investigate the relationship in a wider angular range (2.5 deg. to 60 deg.). Furthermore, image data from an anthropomorphic phantom were collected to corroborate the system analysis. All the images in this study were constructed using a 3D view-weighted cone-beam filtered backprojection algorithm (3D VW CB-FBP). The theoretical analysis reveals that the SSP of linear trajectory tomosynthesis is inversely proportional to tan({theta}/2). This theory was supported by both simulation ({chi}{sup 2}=1.415, DF=7, p=0.985) and phantom experiment (r=0.999, p<0.001) and was further confirmed by an analysis of the reconstructed images of an anthropomorphic phantom. The results imply that the benefit of narrower SSP by increasing angular range quickly diminishes once beyond 40 deg. The advantages of the MTF-d method were also demonstrated.

  20. Holographic Photolysis for Multiple Cell Stimulation in Mouse Hippocampal Slices

    PubMed Central

    Papagiakoumou, Eirini; Ventalon, Cathie; Angulo, María Cecilia; Emiliani, Valentina

    2010-01-01

    Background Advanced light microscopy offers sensitive and non-invasive means to image neural activity and to control signaling with photolysable molecules and, recently, light-gated channels. These approaches require precise and yet flexible light excitation patterns. For synchronous stimulation of subsets of cells, they also require large excitation areas with millisecond and micrometric resolution. We have recently developed a new method for such optical control using a phase holographic modulation of optical wave-fronts, which minimizes power loss, enables rapid switching between excitation patterns, and allows a true 3D sculpting of the excitation volumes. In previous studies we have used holographic photololysis to control glutamate uncaging on single neuronal cells. Here, we extend the use of holographic photolysis for the excitation of multiple neurons and of glial cells. Methods/Principal Findings The system combines a liquid crystal device for holographic patterned photostimulation, high-resolution optical imaging, the HiLo microscopy, to define the stimulated regions and a conventional Ca2+ imaging system to detect neural activity. By means of electrophysiological recordings and calcium imaging in acute hippocampal slices, we show that the use of excitation patterns precisely tailored to the shape of multiple neuronal somata represents a very efficient way for the simultaneous excitation of a group of neurons. In addition, we demonstrate that fast shaped illumination patterns also induce reliable responses in single glial cells. Conclusions/Significance We show that the main advantage of holographic illumination is that it allows for an efficient excitation of multiple cells with a spatiotemporal resolution unachievable with other existing approaches. Although this paper focuses on the photoactivation of caged molecules, our approach will surely prove very efficient for other probes, such as light-gated channels, genetically encoded photoactivatable

  1. Slice-selective J-coupled coherence transfer using symmetric linear phase pulses: applications to localized GABA spectroscopy

    NASA Astrophysics Data System (ADS)

    Shen, Jun

    2003-07-01

    Symmetric, linear phase, slice-selective RF pulses were analyzed theoretically for performing slice-selective coherence transfer. It was shown using numerical simulations of product operators that, when a prefocusing gradient of the same area as that of the refocusing gradient is added, these pulses become slice-selective universal rotator pulses, therefore, capable of performing slice-selective coherence transfer. As an example, a slice-selective universal rotator pulse based on a seven-lobe hamming-filtered sinc pulse was applied to in vivo single-shot simultaneous spectral editing and spatial localization of neurotransmitter GABA in the human brain.

  2. Evaluation of age estimation in forensic medicine by examination of medial clavicular ossification from thin-slice computed tomography images.

    PubMed

    Gurses, Murat Serdar; Inanir, Nursel Turkmen; Gokalp, Gokhan; Fedakar, Recep; Tobcu, Eren; Ocakoglu, Gokhan

    2016-09-01

    Forensic age estimation, a recent topic of research in forensic medicine, is of primary importance to criminal and civil law. Previous studies indicate that the observation of medial clavicular ossification allows for age discrimination along the completed 18th and 21st years of life. Experts recommend that the Schmeling and Kellinghaus methods be used together. In this study, we used these staging methods to retrospectively analyze 725 case studies (385 males, 340 females) of thin-slice computed tomography (CT) images, ranging from 0.6 to 1 mm in thickness, from individuals aged 10 to 35 years. Stage 1 was found at 18 years of age maximum for males, whereas it was found at 17 years of age for females. Stage 2a was found at 18 years of age maximum for both genders. Stage 3c was initially observed at 18 years for both genders. Stage 4 was initially found at 21 years for males and 20 years for females. Stage 5 was initially observed at 25 years for both genders. Of note, stage 3c was found close to 19 years of age for both genders (18.92 years for male, 18.99 years for female), and it may be employed to differentiate along the age majority cutoff. The data obtained from our study were consistent with previous studies. We believe that such a comprehensive database will greatly contribute to future studies focusing on medial clavicular ossification based on thin-slice CT. Moreover, we also recommend that if medial clavicular ossification based on CT is to be examined for forensic age estimation, both methods should be employed together. PMID:27352083

  3. Tube wall thickness measurement apparatus

    DOEpatents

    Lagasse, Paul R.

    1987-01-01

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and circumference by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  4. Tube wall thickness measurement apparatus

    DOEpatents

    Lagasse, P.R.

    1985-06-21

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  5. System for measuring film thickness

    DOEpatents

    Batishko, Charles R.; Kirihara, Leslie J.; Peters, Timothy J.; Rasmussen, Donald E.

    1990-01-01

    A system for determining the thicknesses of thin films of materials exhibiting fluorescence in response to exposure to excitation energy from a suitable source of such energy. A section of film is illuminated with a fixed level of excitation energy from a source such as an argon ion laser emitting blue-green light. The amount of fluorescent light produced by the film over a limited area within the section so illuminated is then measured using a detector such as a photomultiplier tube. Since the amount of fluorescent light produced is a function of the thicknesses of thin films, the thickness of a specific film can be determined by comparing the intensity of fluorescent light produced by this film with the intensity of light produced by similar films of known thicknesses in response to the same amount of excitation energy. The preferred embodiment of the invention uses fiber optic probes in measuring the thicknesses of oil films on the operational components of machinery which are ordinarily obscured from view.

  6. A slice chamber for intracellular and extracellular recording during continuous perfusion.

    PubMed

    Kelso, S R; Nelson, D O; Silva, N L; Boulant, J A

    1983-06-01

    The design of a tissue slice perfusion system is described, and examples are given showing the stability of this system for intracellular and extracellular recordings during changes in perfusion media. The stability of this system is attributed to several features. Mini-drips serve to cushion transient changes in flow rate when switching from one medium to another. Solenoid valves are used to quickly switch perfusion media with minimal mechanical movement. A finely-controlled adjustable flow valve provides a uniform flow rate for all media. Constant tissue temperature is maintained by media perfusion through a thermoelectric Peltier assembly. In addition, a filter paper wick insures that the perfusate is constantly removed without movement in the tissue slices. With this design, the slices are supported on a net at the interface between the perfusion medium and a humidified, oxygenated atmosphere. This arrangement appears to be conducive to tissue viability and facilitates the placement of microelectrodes in the slices. PMID:6311362

  7. Altered magnesium transport in slices of kidney cortex from chemically-induced diabetic rats

    SciTech Connect

    Hoskins, B.

    1981-10-01

    The uptake of magnesium-28 was measured in slices of kidney cortex from rats with alloxan-diabetes and from rats with streptozotocin-diabetes of increasing durations. In both forms of chemically-induced diabetes, magnesium-28 uptake by kidney cortex slices was significantly increased over uptake measured in kidney cortex slices from control rats. Immediate institution of daily insulin therapy to the diabetic rats prevented the diabetes-induced elevated uptake of magnesium without controlling blood glucose levels. Late institution of daily insulin therapy was ineffective in restoring the magnesium uptake to control values. These alterations in magnesium uptake occurred prior to any evidence of nephropathy (via the classic indices of proteinuria and increased BUN levels). The implications of these findings, together with our earlier demonstrations of altered calcium transport by kidney cortex slices from chemically-induced diabetic rats, are discussed in terms of disordered divalent cation transport being at least part of the basic pathogenesis underlying diabetic nephropathy.

  8. An Automated Approach for Slicing Plane Placement in Visual Data Analysis.

    PubMed

    Obermaier, Harald; Joy, Kenneth I

    2015-12-01

    Effective display and visual analysis of complex 3D data is a challenging task. Occlusions, overlaps, and projective distortions-as frequently caused by typical 3D rendering techniques-can be major obstacles to unambiguous and robust data analysis. Slicing planes are a ubiquitous tool to resolve several of these issues. They act as simple clipping geometry to provide clear cut-away views of the data. We propose to enhance the visualization and analysis process by providing methods for automatic placement of such slicing planes based on local optimization of gradient vector flow. The final obtained slicing planes maximize the total amount of information displayed with respect to a pre-specified importance function. We demonstrate how such automated slicing plane placement is able to support and enrich 3D data visualization and analysis in multiple scenarios, such as volume or surface rendering, and evaluate its performance in several benchmark data sets. PMID:26529461

  9. Fermion localization on thick branes

    SciTech Connect

    Melfo, Alejandra; Pantoja, Nelson; Tempo, Jose David

    2006-02-15

    We consider chiral fermion confinement in scalar thick branes, which are known to localize gravity, coupled through a Yukawa term. The conditions for the confinement and their behavior in the thin-wall limit are found for various different BPS branes, including double walls and branes interpolating between different AdS{sub 5} spacetimes. We show that only one massless chiral mode is localized in all these walls, whenever the wall thickness is keep finite. We also show that, independently of wall's thickness, chiral fermionic modes cannot be localized in dS{sub 4} walls embedded in a M{sub 5} spacetime. Finally, massive fermions in double wall spacetimes are also investigated. We find that, besides the massless chiral mode localization, these double walls support quasilocalized massive modes of both chiralities.

  10. LTCC Thick Film Process Characterization

    DOE PAGESBeta

    Girardi, M. A.; Peterson, K. A.; Vianco, P. T.

    2016-05-01

    Low temperature cofired ceramic (LTCC) technology has proven itself in military/space electronics, wireless communication, microsystems, medical and automotive electronics, and sensors. The use of LTCC for high frequency applications is appealing due to its low losses, design flexibility and packaging and integration capability. Moreover, we summarize the LTCC thick film process including some unconventional process steps such as feature machining in the unfired state and thin film definition of outer layer conductors. The LTCC thick film process was characterized to optimize process yields by focusing on these factors: 1) Print location, 2) Print thickness, 3) Drying of tapes and panels,more » 4) Shrinkage upon firing, and 5) Via topography. Statistical methods were used to analyze critical process and product characteristics in the determination towards that optimization goal.« less

  11. Applications of film thickness equations

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1983-01-01

    A number of applications of elastohydrodynamic film thickness expressions were considered. The motion of a steel ball over steel surfaces presenting varying degrees of conformity was examined. The equation for minimum film thickness in elliptical conjunctions under elastohydrodynamic conditions was applied to roller and ball bearings. An involute gear was also introduced, it was again found that the elliptical conjunction expression yielded a conservative estimate of the minimum film thickness. Continuously variable-speed drives like the Perbury gear, which present truly elliptical elastohydrodynamic conjunctions, are favored increasingly in mobile and static machinery. A representative elastohydrodynamic condition for this class of machinery is considered for power transmission equipment. The possibility of elastohydrodynamic films of water or oil forming between locomotive wheels and rails is examined. The important subject of traction on the railways is attracting considerable attention in various countries at the present time. The final example of a synovial joint introduced the equation developed for isoviscous-elastic regimes of lubrication.

  12. A unique approach to accurately measure thickness in thick multilayers.

    PubMed

    Shi, Bing; Hiller, Jon M; Liu, Yuzi; Liu, Chian; Qian, Jun; Gades, Lisa; Wieczorek, Michael J; Marander, Albert T; Maser, Jorg; Assoufid, Lahsen

    2012-05-01

    X-ray optics called multilayer Laue lenses (MLLs) provide a promising path to focusing hard X-rays with high focusing efficiency at a resolution between 5 nm and 20 nm. MLLs consist of thousands of depth-graded thin layers. The thickness of each layer obeys the linear zone plate law. X-ray beamline tests have been performed on magnetron sputter-deposited WSi(2)/Si MLLs at the Advanced Photon Source/Center for Nanoscale Materials 26-ID nanoprobe beamline. However, it is still very challenging to accurately grow each layer at the designed thickness during deposition; errors introduced during thickness measurements of thousands of layers lead to inaccurate MLL structures. Here, a new metrology approach that can accurately measure thickness by introducing regular marks on the cross section of thousands of layers using a focused ion beam is reported. This new measurement method is compared with a previous method. More accurate results are obtained using the new measurement approach. PMID:22514179

  13. Fluidized bed drying characteristics and modeling of ginger ( zingiber officinale) slices

    NASA Astrophysics Data System (ADS)

    Parlak, Nezaket

    2015-08-01

    In this study fluidized bed drying characteristics of ginger have been investigated. The effects of the fluidizing air temperature, velocity, humidity and bed height on the drying performance of ginger slices have been found. The experimental moisture loss data of ginger slices has been fitted to the eight thin layer drying models. Two-term model drying model has shown a better fit to the experimental data with R2 of 0.998 as compared to others.

  14. Organotypic slice cultures containing the preBötzinger complex generate respiratory-like rhythms.

    PubMed

    Phillips, Wiktor S; Herly, Mikkel; Del Negro, Christopher A; Rekling, Jens C

    2016-02-01

    Study of acute brain stem slice preparations in vitro has advanced our understanding of the cellular and synaptic mechanisms of respiratory rhythm generation, but their inherent limitations preclude long-term manipulation and recording experiments. In the current study, we have developed an organotypic slice culture preparation containing the preBötzinger complex (preBötC), the core inspiratory rhythm generator of the ventrolateral brain stem. We measured bilateral synchronous network oscillations, using calcium-sensitive fluorescent dyes, in both ventrolateral (presumably the preBötC) and dorsomedial regions of slice cultures at 7-43 days in vitro. These calcium oscillations appear to be driven by periodic bursts of inspiratory neuronal activity, because whole cell recordings from ventrolateral neurons in culture revealed inspiratory-like drive potentials, and no oscillatory activity was detected from glial fibrillary associated protein-expressing astrocytes in cultures. Acute slices showed a burst frequency of 10.9 ± 4.2 bursts/min, which was not different from that of brain stem slice cultures (13.7 ± 10.6 bursts/min). However, slice cocultures that include two cerebellar explants placed along the dorsolateral border of the brainstem displayed up to 193% faster burst frequency (22.4 ± 8.3 bursts/min) and higher signal amplitude (340%) compared with acute slices. We conclude that preBötC-containing slice cultures retain inspiratory-like rhythmic function and therefore may facilitate lines of experimentation that involve extended incubation (e.g., genetic transfection or chronic drug exposure) while simultaneously being amenable to imaging and electrophysiology at cellular, synaptic, and network levels. PMID:26655824

  15. Method and application of horizontal slice volumetrics to waterflood management and horizontal drilling

    SciTech Connect

    Deshpande, A.; Flemings, P.B.; Huang, J.

    1996-12-31

    A computer mapping program was used to make horizontal slices of pore volume. The goal was to create maps that showed the distribution of pore volume vertically and laterally throughout the reservoir. That information was used for studying waterflood feasibility, monitoring an existing waterflood, and planning a horizontal well. This work was done at the United States Naval Petroleum Reserve No. 1, Elk Hills, CA. The reservoirs are the Miocene aged Northwest Stevens A sands and T & N sands. These sands are a series of stacked deep water turbidites draped across the western nose of a plunging anticline. To determine the reservoir sensitivity to the approach used to calculate horizontal slice volume, two methods were tested. The first involves creation of four isochores, bounded above by the sand top or base and below by the slice top or base, whose volumes are combined to give the slice volume. The second involves creation of a grid of the slice itself from which slice volume is calculated.

  16. Method and application of horizontal slice volumetrics to waterflood management and horizontal drilling

    SciTech Connect

    Deshpande, A.; Flemings, P.B. ); Huang, J. )

    1996-01-01

    A computer mapping program was used to make horizontal slices of pore volume. The goal was to create maps that showed the distribution of pore volume vertically and laterally throughout the reservoir. That information was used for studying waterflood feasibility, monitoring an existing waterflood, and planning a horizontal well. This work was done at the United States Naval Petroleum Reserve No. 1, Elk Hills, CA. The reservoirs are the Miocene aged Northwest Stevens A sands and T N sands. These sands are a series of stacked deep water turbidites draped across the western nose of a plunging anticline. To determine the reservoir sensitivity to the approach used to calculate horizontal slice volume, two methods were tested. The first involves creation of four isochores, bounded above by the sand top or base and below by the slice top or base, whose volumes are combined to give the slice volume. The second involves creation of a grid of the slice itself from which slice volume is calculated.

  17. Simulation and experimental study of DC electric field distribution characteristics of rat hippocampal slices in vitro

    NASA Astrophysics Data System (ADS)

    Zheng, Yu; Dong, Lei; Gao, Yang; Qiu, Qian; Li, Ze-yan; Zhao, Zhe; Chen, Rui-juan; Wang, Hui-quan

    2016-06-01

    Direct current (DC) electric field is a noninvasive neuromodulation tool that can inhibit or facilitate excitability of neurons. Despite its efficacy, the dielectric constant of artificial cerebrospinal fluid and the position and direction of brain slices and other factors can affect the field intensity and distribution acting on the surface of rat hippocampus slices, thus causing errors. In this study, we describe a new analytical method optimized for DC electric fields acting on brain slices, and the design of an external DC electric field stimulator to allow scientific evaluation of brain slices. We investigated parameters regarding the uniformity of electric field distribution and identified the maximal parameters using the finite element method. Then, we selected and simplified slice images using magnetic resonance imaging data and calculated the electric field intensity of the original and simplified models. The electric field simulator induced action potential and excitatory postsynaptic current with intensities of 1, 5, and 10 V/m. This study describes the development of a new electric field stimulator and successfully demonstrates its practicability for scientific evaluation of tissue slices.

  18. A technique for preparing in vitro slices of cat's visual cortex for electrophysiological experiments.

    PubMed

    Kato, H; Ogawa, T

    1981-06-01

    A technique for the preparation and in vitro maintenance of slices of neocortex from cats anesthetized with Nembutal has been described in detail. The visual cortex (posterior lateral gyrus) was cut in slices in situ using a knife consisting of two razor blades with separation of 0.7--1.0 mm. An artificially-defined medium was sprayed abundantly over the brain throughout the slicing procedures. Slices thus obtained were immediately placed between nylon meshes and incubated in a well-oxygenated medium. For recording, one of the slices was transferred to an experimental chamber in which a medium was bubbled and circulated with a gas mixture (5% CO2 in O2) introduced through a glass filter fitted at the bottom. Slices thus treated gave large evoked potentials in response to stimulation of the white matter and high-frequency injury discharges as a macroelectrode was inserted into the tissue. They also allowed stable and high-quality intracellular recordings from single neurons. PMID:7253698

  19. The utility of Thin Slice ratings for predicting language growth in children with autism spectrum disorder.

    PubMed

    Walton, Katherine M; Ingersoll, Brooke R

    2016-04-01

    Literature on "Thin Slice" ratings indicates that a number of personality characteristics and behaviors can be accurately predicted by ratings of very short segments (<5 min) of behavior. This study examined the utility of Thin Slice ratings of young children with autism spectrum disorder for predicting developmental skills and language gains over time. A total of 22 preschool-aged children with autism spectrum disorder participated in a battery of developmental assessments and a video-taped therapist-child interaction at Time 1. They then participated in follow-up testing of language skills and a second therapist-child interaction 6 months later (Time 2). Groups of approximately 25 naïve undergraduate students provided impression ratings ("Thin Slice ratings") about each child's skills and behaviors during 2-min segments taken from the therapist-child interaction videos at each time point. Thin Slice ratings at Time 1 were highly correlated with child scores on several developmental assessments at Time 1. In addition, Thin Slice ratings at Time 1 predicted gain in parent-reported expressive vocabulary over the course of 6 months, over and above the predictive utility of Time 1 vocabulary size. These findings provide preliminary evidence for the concurrent and predictive validity of Thin Slice ratings in young children with autism spectrum disorder. PMID:25991846

  20. Fast whole-brain optical tomography capable of automated slice-collection (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Yuan, Jing; Jiang, Tao; Deng, Lei; Long, Beng; Peng, Jie; Luo, Qingming; Gong, Hui

    2016-03-01

    Acquiring brain-wide composite information of neuroanatomical and molecular phenotyping is crucial to understand brain functions. However, current whole-brain imaging methods based on mechnical sectioning haven't achieved brain-wide acquisition of both neuroanatomical and molecular phenotyping due to the lack of appropriate whole-brain immunostaining of embedded samples. Here, we present a novel strategy of acquiring brain-wide structural and molecular maps in the same brain, combining whole-brain imaging and subsequent immunostaining of automated-collected slices. We developed a whole-brain imaging system capable of automatically imaging and then collecting imaged tissue slices in order. The system contains three parts: structured illumination microscopy for high-throughput optical sectioning, vibratome for high-precision sectioning and slice-collection device for automated collecting of tissue slices. Through our system, we could acquire a whole-brain dataset of agarose-embedded mouse brain at lateral resolution of 0.33 µm with z-interval sampling of 100 µm in 9 h, and automatically collect the imaged slices in sequence. Subsequently, we performed immunohistochemistry of the collected slices in the routine way. We acquired mouse whole-brain imaging datasets of multiple specific types of neurons, proteins and gene expression profiles. We believe our method could accelerate systematic analysis of brain anatomical structure with specific proteins or genes expression information and understanding how the brain processes information and generates behavior.

  1. Tectonic slicing of subducting oceanic crust along plate interfaces: Numerical modeling

    NASA Astrophysics Data System (ADS)

    Ruh, J. B.; Le Pourhiet, L.; Agard, Ph.; Burov, E.; Gerya, T.

    2015-10-01

    Multikilometer-sized slivers of high-pressure low-temperature metamorphic oceanic crust and mantle are observed in many mountain belts. These blueschist and eclogite units were detached from the descending plate during subduction. Large-scale thermo-mechanical numerical models based on finite difference marker-in-cell staggered grid technique are implemented to investigate slicing processes that lead to the detachment of oceanic slivers and their exhumation before the onset of the continental collision phase. In particular, we investigate the role of the serpentinized subcrustal slab mantle in the mechanisms of shallow and deep crustal slicing. Results show that spatially homogeneous serpentinization of the sub-Moho slab mantle leads to complete accretion of oceanic crust within the accretionary wedge. Spatially discontinuous serpentinization of the slab mantle in form of unconnected patches can lead to shallow slicing of the oceanic crust below the accretionary wedge and to its deep slicing at mantle depths depending on the patch length, slab angle, convergence velocity and continental geothermal gradient. P-T paths obtained in this study are compared to natural examples of shallow slicing of the Crescent Terrane below Vancouver Island and deeply sliced crust of the Lago Superiore and Saas-Zermatt units in the Western Alps.

  2. Perfused drop microfluidic device for brain slice culture-based drug discovery.

    PubMed

    Liu, Jing; Pan, Liping; Cheng, Xuanhong; Berdichevsky, Yevgeny

    2016-06-01

    Living slices of brain tissue are widely used to model brain processes in vitro. In addition to basic neurophysiology studies, brain slices are also extensively used for pharmacology, toxicology, and drug discovery research. In these experiments, high parallelism and throughput are critical. Capability to conduct long-term electrical recording experiments may also be necessary to address disease processes that require protein synthesis and neural circuit rewiring. We developed a novel perfused drop microfluidic device for use with long term cultures of brain slices (organotypic cultures). Slices of hippocampus were placed into wells cut in polydimethylsiloxane (PDMS) film. Fluid level in the wells was hydrostatically controlled such that a drop was formed around each slice. The drops were continuously perfused with culture medium through microchannels. We found that viable organotypic hippocampal slice cultures could be maintained for at least 9 days in vitro. PDMS microfluidic network could be readily integrated with substrate-printed microelectrodes for parallel electrical recordings of multiple perfused organotypic cultures on a single MEA chip. We expect that this highly scalable perfused drop microfluidic device will facilitate high-throughput drug discovery and toxicology. PMID:27194028

  3. A Simple Method for Multi-Day Imaging of Slice Cultures

    PubMed Central

    Seidl, Armin H.; Rubel, Edwin W

    2009-01-01

    The organotypic slice culture (Stoppini et al., 1991) has become the method of choice to answer a variety of questions in neuroscience. For many experiments however, it would be beneficial to image or manipulate a slice culture repeatedly, for example over the course of many days. We prepared organotypic slice cultures of the auditory brainstem of P3 and P4 mice and kept them in vitro for up to 4 weeks. Single cells in the auditory brainstem were transfected with plasmids expressing fluorescent proteins by way of electroporation (Haas et al., 2001). The culture was then placed in a chamber perfused with oxygenated ACSF and the labeled cell imaged with an inverted wide-field microscope repeatedly for multiple days, recording several time-points per day, before returning the slice to the incubator. We describe a simple method to image a slice culture preparation over to the course of multiple days and over many continuous hours, without noticeable damage to the tissue or photobleaching. Our method employs a simple, inexpensive custom-built insulator constructed around the microscope to maintain controlled temperature, and uses a perfusion chamber as used for in vitro slice recordings. PMID:19565635

  4. Regional variations in protein phosphorylating activity in rat brain studied in micro-slices labeled with ( sup 32 P)phosphate

    SciTech Connect

    Rodnight, R.; Leal, R. )

    1990-01-01

    Regional variations in protein phosphorylating activity in the rat brain were studied. Micro-slices (1 mm diameter) were prepared from 19 brain areas, phosphoproteins labeled by incubation with ({sup 32}P)phosphate, and the tissue analyzed by nonequilibrium two-dimensional electrophoresis and autoradiography. Attention was focused on three phosphorylating systems that showed consistent variation in activity. (1) A system that phosphorylates a substrate of 47 kDa (ppH-47) whose activity was highest in the hippocampus. The next highest activity of this system was observed in the globus pallidus, followed by the periventricular gray matter of the aqueduct, lateral septum, cerebellar cortex, entorhinal cortex, hypothalamus, mammillary nuclei, amygdala, and substantia nigra. Activity was low or undetectable in the cerebral cortex, neostriatum, and the colliculi. (2) A system that phosphorylates a substrate of 50 kDa (ppC-50) whose activity was highest in the caudate nucleus. The activity of this system was roughly inversely correlated with that of the ppH-47 system. (3) The protein kinase C system that phosphorylates an 82- to 87-kDa substrate known as MARCKS. The highest activity of this system was observed in the cerebellar cortex, followed by the hypothalamus, mammillary nuclei, periventricular gray matter of the aqueduct, and the superior colliculus. Activity of this system was relatively low in several regions of the cerebral cortex, the neostriatum, and the inferior colliculus.

  5. Dynamic Bowtie Filter for Cone-Beam/Multi-Slice CT

    PubMed Central

    Liu, Fenglin; Yang, Qingsong; Cong, Wenxiang; Wang, Ge

    2014-01-01

    A pre-patient attenuator (“bowtie filter” or “bowtie”) is used to modulate an incoming x-ray beam as a function of the angle of the x-ray with respect to a patient to balance the photon flux on a detector array. While the current dynamic bowtie design is focused on fan-beam geometry, in this study we propose a methodology for dynamic bowtie design in multi-slice/cone-beam geometry. The proposed 3D dynamic bowtie is an extension of the 2D prior art. The 3D bowtie consists of a highly attenuating bowtie (HB) filled in with heavy liquid and a weakly attenuating bowtie (WB) immersed in the liquid of the HB. The HB targets a balanced flux distribution on a detector array when no object is in the field of view (FOV). The WB compensates for an object in the FOV, and hence is a scaled-down version of the object. The WB is rotated and translated in synchrony with the source rotation and patient translation so that the overall flux balance is maintained on the detector array. First, the mathematical models of different scanning modes are established for an elliptical water phantom. Then, a numerical simulation study is performed to compare the performance of the scanning modes in the cases of the water phantom and a patient cross-section without any bowtie and with a dynamic bowtie. The dynamic bowtie can equalize the numbers of detected photons in the case of the water phantom. In practical cases, the dynamic bowtie can effectively reduce the dynamic range of detected signals inside the FOV. Furthermore, the WB can be individualized using a 3D printing technique as the gold standard. We have extended the dynamic bowtie concept from 2D to 3D by using highly attenuating liquid and moving a scale-reduced negative copy of an object being scanned. Our methodology can be applied to reduce radiation dose and facilitate photon-counting detection. PMID:25051067

  6. Dopaminergic toxicity of the herbicide atrazine in rat striatal slices

    PubMed Central

    Filipov, Nikolay M.; Stewart, Molly A.; Carr, Russell L.; Sistrunk, Shannon C.

    2007-01-01

    A possible link between Parkinson’s disease and pesticide exposure has been suggested, and recently it was shown that the herbicide atrazine (ATR) modulates catecholamine metabolism in PC12 cells and affects basal ganglia function in vivo. Hence, the objectives of this study were to: (i) determine if ATR is capable of modulating dopamine (DA) metabolism in striatal tissue slices in vitro and (ii) to explore possible mechanisms of its effects. Striatal tissues from adult male Sprague Dawley rats were incubated with up to 500 μM ATR in a metabolic shaker bath at 37 °C and an atmosphere of 95% O2 and 5% CO2 for 4 h. At the end of incubation, samples were collected for both tissue and media levels of DA and its metabolites (3,4-dihydroxyphenylacetic acid, DOPAC and homovanillic acid, HVA), which were determined by high-performance liquid chromatography with electrochemical detection (HPLC-ECD). To gain some mechanistic insight in to the way ATR affects DA metabolism, several pharmacological manipulations were performed. Striata exposed to ATR at concentrations of 100 μM and greater had a dose-dependent decrease of tissue levels of DA. At doses of ATR 50 μM and greater, the DOPAC+HVA/DA ratio was dose-dependently increased. Tyrosine hydroxylase (TH, the rate-limiting enzyme in DA synthesis) protein levels and activity were not affected by ATR treatment. However, high potassium induced DA release into the medium was decreased, whereas the increase in media DA observed in the presence of the DA uptake inhibitor nomifensine was increased even further by ATR in a dose-dependent manner. All of these effects of ATR were observed at levels that were not toxic to the tissue, as LDH release into the medium (lactate dehydrogenase, an index of non-specific cytotoxicity) was not affected by ATR. Taken together, results from this study suggest that ATR decreases tissue DA levels not by affecting TH activity, but possibly by interfering with the vesicular storage and

  7. Eddy current thickness measurement apparatus

    DOEpatents

    Rosen, Gary J.; Sinclair, Frank; Soskov, Alexander; Buff, James S.

    2015-06-16

    A sheet of a material is disposed in a melt of the material. The sheet is formed using a cooling plate in one instance. An exciting coil and sensing coil are positioned downstream of the cooling plate. The exciting coil and sensing coil use eddy currents to determine a thickness of the solid sheet on top of the melt.

  8. Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography.

    PubMed

    Burgstahler, Christof; Reimann, Anja; Brodoefel, Harald; Daferner, Ulrike; Herberts, Tina; Tsiflikas, Ilias; Thomas, Christoph; Drosch, Tanja; Schroeder, Stephen; Heuschmid, Martin

    2009-03-01

    Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n = 90; Siemens Sensation 64: n = 91; Siemens Definition: n = 75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347 +/- 13 vs. 254 +/- 14 (64-MSCT) vs. 233 +/- 11 (16-MSCT) HU], LM (362 +/- 11/275 +/- 12/262 +/- 9), LAD (332 +/- 17/248 +/- 19/219 +/- 14) and LCX (310 +/- 12/210 +/- 13/221 +/- 10, all p < 0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p < 0.05). BMI had no impact on the CA ratio in DSCT only (p < 0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the

  9. Thick resist for MEMS processing

    NASA Astrophysics Data System (ADS)

    Brown, Joe; Hamel, Clifford

    2001-11-01

    The need for technical innovation is always present in today's economy. Microfabrication methods have evolved in support of the demand for smaller and faster integrated circuits with price performance improvements always in the scope of the manufacturing design engineer. The dispersion of processing technology spans well beyond IC fabrication today with batch fabrication and wafer scale processing lending advantages to MEMES applications from biotechnology to consumer electronics from oil exploration to aerospace. Today the demand for innovative processing techniques that enable technology is apparent where only a few years ago appeared too costly or not reliable. In high volume applications where yield and cost improvements are measured in fractions of a percent it is imperative to have process technologies that produce consistent results. Only a few years ago thick resist coatings were limited to thickness less than 20 microns. Factors such as uniformity, edge bead and multiple coatings made high volume production impossible. New developments in photoresist formulation combined with advanced coating equipment techniques that closely controls process parameters have enable thick photoresist coatings of 70 microns with acceptable uniformity and edge bead in one pass. Packaging of microelectronic and micromechanical devices is often a significant cost factor and a reliability issue for high volume low cost production. Technologies such as flip- chip assembly provide a solution for cost and reliability improvements over wire bond techniques. The processing for such technology demands dimensional control and presents a significant cost savings if it were compatible with mainstream technologies. Thick photoresist layers, with good sidewall control would allow wafer-bumping technologies to penetrate the barriers to yield and production where costs for technology are the overriding issue. Single pass processing is paramount to the manufacturability of packaging

  10. Tracking and modeling norovirus transmission during mechanical slicing of globe tomatoes.

    PubMed

    Shieh, Y Carol; Tortorello, Mary Lou; Fleischman, Gregory J; Li, Di; Schaffner, Donald W

    2014-06-16

    Recent epidemiological evidence indicates that preparation of fresh produce for use as ingredients in ready-to-eat food in commercial settings has been a significant source of the norovirus (NoV) infections in the U.S. This research investigated the dissemination of NoV from a single tomato to many others via the use of an 11-horizontal blade slicer commonly found in restaurants or sandwich shops. A total of eight trials were conducted. The source of contamination in each trial was a soak-inoculated, air-dried globe tomato containing ~8log10 murine norovirus (MNV). Each trial began by slicing a single un-inoculated tomato in the slicer, followed by slicing an inoculated tomato. This was then followed by slicing 9 to 27 un-inoculated tomatoes. A similar and constant hand pressure on the slicer was used in every trial. Three slices from each tomato were collected for virus elution, concentration, and extraction before RT-PCR detection of MNV. The change in MNV per sliced tomato was averaged over all eight trials, and two mathematical models were fit to the average data using a logarithmic model or a power model. Regression analysis determined that the equation that best fit the data was y=-0.903∗ln(x)+7.945, where y=log10 MNV per slicing and x=tomato slicing number. An acceptable fit (R(2)=0.913) was indicated. The MNV levels transferred (y) generally decreased as the number of tomatoes sliced (x) increased, with some exceptions. Infrequent but erratic transfers, where the MNV level of a subsequent tomato was higher than that of a preceding tomato, occurred in later transfer of some trials. In contrast, the first and second transfers of each trial were always shown to have sharply decreased levels of MNV from the inoculum. The MNV log10 reduction per slicing event changes throughout the process: with a predicted 0.63log10 reduction from tomato 1 to tomato 2 (76% reduction); a 0.07log10 reduction predicted from tomato 13 to tomato 14 (a 14% reduction); and 0.03log10

  11. In Vivo Measurement of the Subchondral Bone Thickness of Lumbar Facet Joint Using Magnetic Resonance Imaging

    PubMed Central

    Duan, C. Y.; Espinoza Orías, A. A.; Shott, S.; An, H. S.; Andersson, G.B.J.; Hu, J.Z.; Lu, H. B.; Inoue, N.

    2010-01-01

    Summary Objective To measure in vivo thicknesses of the facet joint subchondral bone across genders, age groups, with or without low back pain symptom groups and spinal levels. Methods Lumbar (L1–L2 to L5-S1) magnetic resonance (MR) imaging was performed in 81 subjects (41 males and 40 females, mean age 37.6 years). Thicknesses of the subchondral bone were measured in 1,620 facet joints using the MR images with custom-written image processing algorithms together with a multi-threshold segmentation technique using each facet joint’s middle axial-slice. This method was validated with 12 cadaver facet joints, scanned with both MR and micro-computed tomography images. Results An overall average thickness value for the 1,620 analyzed joints was measured as 1.56 ± 0.01 mm. The subchondral bone thickness values showed significant increases with successive lower spinal levels in the subjects without low back pain. The facet joint subchondral bone thickness in asymptomatic females was much smaller than in asymptomatic males. Mean subchondral bone thickness in the superior facet was greater than that in the inferior facet in both female and male asymptomatic subjects. Conclusions This study is the first to quantitatively show subchondral bone thickness using a validated MR-based technique. The subchondral bone thickness was greater in asymptomatic males and increased with each successive lower spinal level. These findings may suggest that the subchondral bone thickness increases with loading. Furthermore, the superior facet subchondral bone was thicker than the inferior facet in all cases regardless of gender, age or spinal level in the subjects without low back pain. More research is needed to link subchondral bone microstructure to facet joint kinematics and spinal loads. PMID:21034837

  12. A shape-based statistical method to retrieve 2D TRUS-MR slice correspondence for prostate biopsy

    NASA Astrophysics Data System (ADS)

    Mitra, Jhimli; Srikantha, Abhilash; Sidibé, Désiré; Martí, Robert; Oliver, Arnau; Lladó, Xavier; Ghose, Soumya; Vilanova, Joan C.; Comet, Josep; Meriaudeau, Fabrice

    2012-02-01

    This paper presents a method based on shape-context and statistical measures to match interventional 2D Trans Rectal Ultrasound (TRUS) slice during prostate biopsy to a 2D Magnetic Resonance (MR) slice of a pre-acquired prostate volume. Accurate biopsy tissue sampling requires translation of the MR slice information on the TRUS guided biopsy slice. However, this translation or fusion requires the knowledge of the spatial position of the TRUS slice and this is only possible with the use of an electro-magnetic (EM) tracker attached to the TRUS probe. Since, the use of EM tracker is not common in clinical practice and 3D TRUS is not used during biopsy, we propose to perform an analysis based on shape and information theory to reach close enough to the actual MR slice as validated by experts. The Bhattacharyya distance is used to find point correspondences between shape-context representations of the prostate contours. Thereafter, Chi-square distance is used to find out those MR slices where the prostates closely match with that of the TRUS slice. Normalized Mutual Information (NMI) values of the TRUS slice with each of the axial MR slices are computed after rigid alignment and consecutively a strategic elimination based on a set of rules between the Chi-square distances and the NMI leads to the required MR slice. We validated our method for TRUS axial slices of 15 patients, of which 11 results matched at least one experts validation and the remaining 4 are at most one slice away from the expert validations.

  13. Effect of specimen thickness on DHC velocity for Zr-2.5Nb alloy pressure tube material

    NASA Astrophysics Data System (ADS)

    Sunil, S.; Bind, A. K.; Khandelwal, H. K.; Singh, R. N.; Chakravartty, J. K.

    2015-12-01

    Zr-2.5Nb alloy pressure tubes used in pressurized heavy water reactors (PHWR) are susceptible to failure by Delayed Hydride Cracking (DHC), which is a form of localized hydride-embrittlement phenomenon manifested in the presence of a hydrostatic stress gradient and hydrogen concentration above a threshold limit as a sub-critical crack growth process in hydride forming metals. The DHC parameters used for safety assessment are DHC velocity (VDHC) and a threshold stress intensity factor (KIH). In this work DHC velocity was determined for Zr-2.5Nb pressure tube material at 250 and 280 °C using specimens of thickness between 1 mm and 4.5 mm. The DHC velocity was found to increase with increase in specimen thickness at 250 °C and 280 °C. Significant amount of tunneling of the crack was observed for 1-mm and 2-mm thick specimens at 250 °C and 280 °C, with the degree of tunneling increasing with decrease in thickness and increase in test temperature.

  14. Reducing shield thickness and backscattered radiation using a multilayered shield for 6–10 MeV electron beams.

    PubMed

    Butson, Martin; Chen, Tom; Rattanavoang, Somkhit; Hellyer, James; Gray, Alison; Nelson, Vinod; Short, Richard; Rajapakse, Satya; Lee, James; Fogarty, Gerald; Izard, Michael; Hill, Robin

    2015-12-01

    Intraoral and external electron shields used in radiotherapy are designed to minimize radiation exposure to non-treatment tissue. Sites where shields are used include but are not limited to, the treatment of lips, cheeks and ears whilst shielding the underlying oral cavity, tongue, gingival or temporal region. A commonly known and published effect, concerns the enhancement in dose that can occur on the beam side on an electron shield caused by an increase in electron backscatter radiation. In this work a lead shield has been designed incorporating copper, aluminium and wax in a step down filter arrangement to minimise backscatter whilst minimizing overall shield thickness for better clinical setup and ease of use. For electron beams ranging from 6 to 10 MeV, a standard shield design of 4 mm lead, 0.6 mm copper, 1.0 mm aluminium and 1.5 mm wax (3.1 mm added filtration, 7.1 mm total thickness) provided adequate backscatter and transmission reduction to match a standard 4.5 mm lead and 10 mm wax (total thickness 14.5 mm) electron shield. Dose enhancement values of no more than 10 % were measured utilising this shield design with a 50 % reduction in shield thickness. The thinner shield will not only allow easier patient set up but should be tolerated better by patients when mucosal reactions occur as they place less physical pressure on these sites during treatment due to their smaller size. PMID:26482529

  15. Thick Silicon Double-Sided Strip Detectors for Low-Energy Small-Animal SPECT

    PubMed Central

    Shokouhi, Sepideh; McDonald, Benjamin S.; Durko, Heather L.; Fritz, Mark A.; Furenlid, Lars R.; Peterson, Todd E.

    2010-01-01

    This work presents characterization studies of thick silicon double-sided strip detectors for a high-resolution small-animal SPECT. The dimension of these detectors is 60.4 mm × 60.4 mm × 1 mm. There are 1024 strips on each side that give the coordinates of the photon interaction, with each strip processed by a separate ASIC channel. Our measurement shows that intrinsic spatial resolution equivalent to the 59 μm strip pitch is attainable. Good trigger uniformity can be achieved by proper setting of a 4-bit DAC in each ASIC channel to remove trigger threshold variations. This is particularly important for triggering at low energies. The thick silicon DSSD (Double-sided strip detector) shows high potential for small-animal SPECT. PMID:20686626

  16. Measurement of the hyperelastic properties of tissue slices with tumour inclusion.

    PubMed

    O'Hagan, Joseph J; Samani, Abbas

    2008-12-21

    The elastic and hyperelastic properties of biological soft tissues have been of interest to the medical community as there are several applications where parameters characterizing these properties are critical for a reliable outcome. This includes applications such as surgery planning, needle biopsy and cancer diagnosis using medical imaging. While there has been considerable research on the measurement of the linear elastic modulus of small tissue samples, little research has been conducted for measuring parameters that characterize nonlinear elasticity of tissues included in slice specimens. In this paper, we present a method of measuring the hyperelastic parameters of tissue slice samples with tumours. In this method, to measure the hyperelastic properties of a tumour within a slice sample, the tumour was indented to acquire its force-displacement response while the slice remained intact. To calculate the hyperelastic parameters from the acquired data, we developed two inversion techniques that use the slice nonlinear finite element model as their forward problem solver. One of these techniques was based on nonlinear optimization while the other is a novel iterative technique that processes the variable slopes of the force-displacement response to calculate the hyperelastic parameters. The latter was developed specifically for the Yeoh and the second-order polynomial hyperelastic models, since we found that the other optimization-based inversion technique did not perform well with these models. To validate the proposed techniques, we performed numerical and phantom experiments. While we were able to achieve convergence with wide ranges of parameters of initial guesses to within 1% error with the numerical simulation experiments, we achieved convergence to within errors of around 5% with the tissue mimicking phantoms. Moreover, we successfully applied these techniques to data we acquired from nine pathological breast tissue slice specimens where the goal was to

  17. Measurement of the hyperelastic properties of tissue slices with tumour inclusion

    NASA Astrophysics Data System (ADS)

    O'Hagan, Joseph J.; Samani, Abbas

    2008-12-01

    The elastic and hyperelastic properties of biological soft tissues have been of interest to the medical community as there are several applications where parameters characterizing these properties are critical for a reliable outcome. This includes applications such as surgery planning, needle biopsy and cancer diagnosis using medical imaging. While there has been considerable research on the measurement of the linear elastic modulus of small tissue samples, little research has been conducted for measuring parameters that characterize nonlinear elasticity of tissues included in slice specimens. In this paper, we present a method of measuring the hyperelastic parameters of tissue slice samples with tumours. In this method, to measure the hyperelastic properties of a tumour within a slice sample, the tumour was indented to acquire its force-displacement response while the slice remained intact. To calculate the hyperelastic parameters from the acquired data, we developed two inversion techniques that use the slice nonlinear finite element model as their forward problem solver. One of these techniques was based on nonlinear optimization while the other is a novel iterative technique that processes the variable slopes of the force-displacement response to calculate the hyperelastic parameters. The latter was developed specifically for the Yeoh and the second-order polynomial hyperelastic models, since we found that the other optimization-based inversion technique did not perform well with these models. To validate the proposed techniques, we performed numerical and phantom experiments. While we were able to achieve convergence with wide ranges of parameters of initial guesses to within 1% error with the numerical simulation experiments, we achieved convergence to within errors of around 5% with the tissue mimicking phantoms. Moreover, we successfully applied these techniques to data we acquired from nine pathological breast tissue slice specimens where the goal was to

  18. Effect of the amount of thickness reduction on color and translucency of dental monolithic zirconia ceramics

    PubMed Central

    Lee, Jai-Bong

    2016-01-01

    PURPOSE This study investigated the effect of amount of thickness reduction on color and translucency of dental monolithic zirconia ceramics. MATERIALS AND METHODS One-hundred sixty-five monolithic zirconia specimens (16.3 mm × 16.3 mm × 2.0 mm) were divided into 5 groups (Group I to V) according to the number of A2-coloring liquid applications. Each group was then divided into 11 subgroups by reducing the thickness up to 1.0 mm in 0.1-mm increments (Subgroup 0 to 10, n=3). Colors and spectral distributions were measured according to CIELAB on a reflection spectrophotometer. All measurements were performed on five different areas of each specimen. Color difference (ΔE*ab) and translucency parameter (TP) were calculated. Data were analyzed using one-way ANOVA and multiple comparison Scheffé test (α=.05). RESULTS There were significant differences in CIE L* between Subgroup 0 and other subgroups in all groups. CIE a* increased (0.52thickness reduction. Perceptible color differences (ΔE* ab>3.7) were obtained between Subgroup 0 and other subgroups. TP values generally increased as the thickness reduction increased in all groups (R2>0.89, P<.001). CONCLUSION Increasing thickness reduction reduces lightness and increases a reddish, bluish appearance, and translucency of monolithic zirconia ceramics. PMID:26949486

  19. Accurate thickness measurement of graphene

    NASA Astrophysics Data System (ADS)

    Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.

    2016-03-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  20. Preparation of thick molybdenum targets

    NASA Technical Reports Server (NTRS)

    Singh, J. J.

    1974-01-01

    Thick natural molybdenum deposits on nickel plated copper substrates were prepared by thermal decomposition of molybdenum hexacarbonyl vapors on a heated surface in an inert gas atmosphere. The molybdenum metal atoms are firmly bonded to the substrate atoms, thus providing an excellent thermal contact across the junction. Molybdenum targets thus prepared should be useful for internal bombardment in a cyclotron where thermal energy inputs can exceed 10 kW.

  1. Soliton models for thick branes

    NASA Astrophysics Data System (ADS)

    Peyravi, Marzieh; Riazi, Nematollah; Lobo, Francisco S. N.

    2016-05-01

    In this work, we present new soliton solutions for thick branes in 4+1 dimensions. In particular, we consider brane models based on the sine-Gordon (SG), φ 4 and φ 6 scalar fields, which have broken Z2 symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the w^2 term in the expansion of the potential for the resulting Schrödinger-like equation, where w is the five-dimensional coordinate. It turns out that the φ ^4 brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and φ ^6 branes.

  2. Central Corneal Thickness in Children

    PubMed Central

    2011-01-01

    Objective To report the central corneal thickness (CCT) in healthy white, African-American, and Hispanic children from birth to 17 years of age. Design Prospective observational multicenter study. Central corneal thickness was measured with a hand-held contact pachymeter. Results Two thousand seventy-nine children were included in the study, with ages ranging from day of birth to 17 years. Included were 807 white, 494 Hispanic, and 474 African-American individuals, in addition to Asian, unknown and mixed race individuals. African-American children had thinner corneas on average than that of both white (p< .001) and Hispanic children (p< .001) by approximately 20 micrometers. Thicker median CCT was observed with each successive year of age from age 1 to 11 years, with year-to-year differences steadily decreasing and reaching a plateau after age 11 at 573 micrometers in white and Hispanic children and 551 micrometers in African-American children. For every 100 micrometers of thicker CCT measured, the intraocular pressure was 1.5 mmHg higher on average (p< 0.001). For every diopter of increased myopic refractive error (p< 0.001) CCT was 1 micrometer thinner on average. Conclusions Median CCT increases with age from 1 to 11 years with the greatest increase present in the youngest age groups. African-American children on average have thinner central corneas than white and Hispanic children, while white and Hispanic children demonstrate similar central corneal thickness. PMID:21911662

  3. Thickness of western mare basalts

    NASA Technical Reports Server (NTRS)

    Dehon, R. A.

    1979-01-01

    An isopach map of the basalt thickness in the western mare basins is constructed from measurements of the exposed external rim height of partially buried craters. The data, although numerically sparse, is sufficiently distributed to yield gross thickness variations. The average basalt thickness in Oceanus Procellarum and adjacent regions is 400 m with local lenses in excess of 1500 m in the circular maria. The total volume of basalt in the western maria is estimated to be in the range of 1.5 x 10 to the 6th power cu km. The chief distinction between the eastern and western maria appears to be one of basalt volumes erupted to the surface. Maximum volumes of basalt are deposited west of the central highlands and flood subjacent terrain to a greater extent than on the east. The surface structures of the western maria reflect the probability of a greater degree of isostatic response to a larger surface loading by the greater accumulation of mare basalt.

  4. Measuring Metal Thickness With an Electric Probe

    NASA Technical Reports Server (NTRS)

    Shumka, A.

    1986-01-01

    Thickness of metal parts measured from one side with aid of Kelvin probe. Method developed for measuring thickness of end plate on sealed metal bellows from outside. Suitable for thicknesses of few thousandth's of inch (few hundred micrometers). Method also used to determine thickness of metal coatings applied by sputtering, electroplating, and flame spraying.

  5. Measuring Rind Thickness on Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Johnson, C.; Miller, J.; Brown, H.

    1985-01-01

    Nondestructive test determines rind thickness of polyurethane foam. Surface harness of foam measured by Shore durometer method: hardness on Shore D scale correlates well with rind thickness. Shore D hardness of 20, for example, indicates rind thickness of 0.04 inch (1 millimeter). New hardness test makes it easy to determine rind thickness of sample nondestructively and to adjust fabrication variables accordingly.

  6. Hybrid-integrated polarization mode converters and low-voltage electro-optic modulators using crystal-ion-sliced LiNbO3 films

    NASA Astrophysics Data System (ADS)

    Radojevic, Antonije M.; Fujita, Junichiro; Eldada, Louay A.

    2002-06-01

    Lithium Niobate (LiNbO3) films produced by the crystal ion slicing (CIS) method are introduced in various components in use in the optical telecommunications market. The CIS technique employs high-energy ion implantation to create a narrow (~0.2 micrometers ) planar layer of localized damage, buried ~10 micrometers beneath the surface of the implanted LiNbO3 wafers. This sacrificial layer allows for slicing of microns-thick LiNbO3 films, either by selective wet chemical etching or by thermal shock. The obtained films have bulk material properties and morphology suitable for integrated optics applications. Slices of X-cut LiNbO3 were used to produce zero-order wave retarders that can be inserted in slots cut into planar lightwave circuits, resulting in TE-TM polarization mode conversion with high extinction ratio (30 dB) and low excess loss (<0.1 dB). Conventional LiNbO3 waveguide fabrication techniques were combined with the CIS process to produce CIS films of Z-cut LiNbO3 with optical circuits patterned prior to lift-off, having propagation losses typical of bulk LiNbO3 waveguides. Using thin sheets of LiNbO3, velocity- and impedance-matched modulators can be fabricated with low V(pi )L(~7.6 V.cm) and low microwave losses (0.3 db/cm.GHz1/2). The CIS film optical circuits can be integrated into hybrid systems with otherwise incompatible, yet technologically important materials platforms.

  7. Real-time monitoring of superoxide accumulation and antioxidant activity in a brain slice model using an electrochemical cytochrome c biosensor

    PubMed Central

    Ganesana, Mallikarjunarao; Erlichman, Joseph S.; Andreescu, Silvana

    2012-01-01

    The overproduction of reactive oxygen species and resulting damage are central to the pathology of many diseases. The study of the temporal and spatial accumulation of reactive oxygen species has been limited due to the lack of specific probes and techniques capable of continuous measurement. We demonstrate the use of a miniaturized electrochemical cytochrome C (Cyt C) biosensor for real-time measurements and quantitative assessment of superoxide production and inactivation by natural and engineered antioxidants in acutely prepared brain slices from mice. During control conditions, superoxide radicals produced from the hippocampal region of the brain in 400 μm thick sections were well within the range of detection of the electrode. Exposure of the slices to ischemic conditions increased the superoxide production two fold and measurements from the slices were stable over a 3–4 hour period. The stilbene derivative and anion channel inhibitor, 4,4′-diisothiocyano-2,2′-disulfonic stilbene (DIDS), markedly reduced the extracellular superoxide signal under control conditions suggesting that a transmembrane flux of superoxide into the extracellular space may occur as part of normal redox signaling. The specificity of the electrode for superoxide released by cells in the hippocampus was verified by the exogenous addition of superoxide dismutase (SOD) which decreased the superoxide signal in a dose-dependent manner. Similar results were seen with the addition of the SOD-mimetic, cerium oxide nanoparticles (nanoceria) where the superoxide anion radical scavenging activity of nanoceria with an average diameter of 15 nm was equivalent to 527 U of SOD for each 1 μg/ml of nanoceria added. This study demonstrates the potential of electrochemical biosensors for studying real-time dynamics of reactive oxygen species in a biological model and the utility of these measurements in defining the relative contribution of superoxide to oxidative injury. PMID:23085519

  8. Three-dimensional image reconstruction for PET by multi-slice rebinning and axial image filtering.

    PubMed

    Lewittt, R M; Muehllehner, G; Karpt, J S

    1994-03-01

    A fast method is described for reconstructing volume images from three-dimensional (3D) coincidence data in positron emission tomography (PET). The reconstruction method makes use of all coincidence data acquired by high-sensitivity PET systems that do not have inter-slice absorbers (septa) to restrict the axial acceptance angle. The reconstruction method requires only a small amount of storage and computation, making it well suited for dynamic and whole-body studies. The method consists of three steps: (i) rebinning of coincidence data into a stack of 2D sinograms; (ii) slice-by-slice reconstruction of the sinogram associated with each slice to produce a preliminary 3D image having strong blurring in the axial (z) direction, but with different blurring at different z positions; and (iii) spatially variant filtering of the 3D image in the axial direction (i.e. 1D filtering in z for each x-y column) to produce the final image. The first step involves a new form of the rebinning operation in which multiple sinograms are incremented for each oblique coincidence line (multi-slice rebinning). The axial filtering step is formulated and implemented using the singular value decomposition (SVD). The method has been applied successfully to simulated data and to measured data for different kinds of phantom (multiple point sources, multiple discs, a cylinder with cold spheres, and a 3D brain phantom). PMID:15551583

  9. Activity of putative cognition enhancers in kynurenate test performed with human neocortex slices.

    PubMed

    Pittaluga, A; Pattarini, R; Andrioli, G C; Viola, C; Munari, C; Raiteri, M

    1999-07-01

    Some cognition enhancers were previously shown to potently prevent antagonism of the N-methyl-D-aspartate (NMDA)-evoked release of norepinephrine (NE) brought about in slices of rat hippocampus by kynurenic acid, an endogenous NMDA receptor blocker. We have examined the impact of putative nootropic agents in the kynurenate test performed with slices of human cerebral cortex from patients undergoing neurosurgery. In slices of human neocortex, local application of NMDA evoked release of [3H]NE; the effect of NMDA was antagonized by several NMDA receptor antagonists, including kynurenic acid. The antagonism of the NMDA-evoked [3H]NE release produced by 300 microM kynurenate was potently (EC50 <10 microM) prevented by most of the nootropics tested, including aniracetam, oxiracetam, D-cycloserine, and the glutamate analog CR 2249 (but not its enantiomer CR 2361). Nicotine or tacrine (up to 10 microM) did not show any effect in the kynurenate test. Nicotine (30-100 microM) itself increased the release of [3H]NE; interestingly, the nicotine-evoked overflow was blocked not only by the nicotin receptor antagonist mecamylamine but also by NMDA receptor antagonists, suggesting an indirect mechanism mediated by glutamate/aspartate release. To conclude, the similarities between the data obtained here with human neocortex slices and those previously obtained in the rat indicate that the kynurenate test performed with rat brain slices may represent a useful biochemical assay to study cognition-enhancing drugs. PMID:10381808

  10. Human Organotypic Cultured Cardiac Slices: New Platform For High Throughput Preclinical Human Trials

    PubMed Central

    Kang, C.; Qiao, Y.; Li, G.; Baechle, K.; Camelliti, P.; Rentschler, S.; Efimov, I. R.

    2016-01-01

    Translation of novel therapies from bench to bedside is hampered by profound disparities between animal and human genetics and physiology. The ability to test for efficacy and cardiotoxicity in a clinically relevant human model system would enable more rapid therapy development. We have developed a preclinical platform for validation of new therapies in human heart tissue using organotypic slices isolated from donor and end-stage failing hearts. A major advantage of the slices when compared with human iPS-derived cardiomyocytes is that native tissue architecture and extracellular matrix are preserved, thereby allowing investigation of multi-cellular physiology in normal or diseased myocardium. To validate this model, we used optical mapping of transmembrane potential and calcium transients. We found that normal human electrophysiology is preserved in slice preparations when compared with intact hearts, including slices obtained from the region of the sinus node. Physiology is maintained in slices during culture, enabling testing the acute and chronic effects of pharmacological, gene, cell, optogenetic, device, and other therapies. This methodology offers a powerful high-throughput platform for assessing the physiological response of the human heart to disease and novel putative therapies. PMID:27356882

  11. Developmental Decrease of Neuronal Chloride Concentration Is Independent of Trauma in Thalamocortical Brain Slices

    PubMed Central

    Glykys, Joseph; Staley, Kevin J.

    2016-01-01

    The intraneuronal chloride concentration ([Cl-]i) is paramount for determining the polarity of signaling at GABAA synapses in the central nervous system. Sectioning hippocampal brain slices increases [Cl-]i in the superficial layers. It is not known whether cutting trauma also increases [Cl-]i in the neocortex and thalamus, and whether the effects of trauma change during development. We used Cl- imaging to study the [Cl-]i vs. the distance from the cut surface in acute thalamocortical slices from mice at developmental ages ranging from post-natal day 5 (P5) to P20. We demonstrate: 1) [Cl-]i is higher in the most superficial areas in both neocortical and thalamic brain slices at all ages tested and, 2) there is a developmental decrease in [Cl-]i that is independent of acute trauma caused by brain slicing. We conclude that [Cl-]i has a developmental progression during P5-20 in both the neocortex and thalamus. However, in both brain regions and during development the neurons closest to the slicing trauma have an elevated [Cl-]i. PMID:27337272

  12. Mathematical modeling of drying of potato slices in a forced convective dryer based on important parameters.

    PubMed

    Naderinezhad, Samira; Etesami, Nasrin; Poormalek Najafabady, Arefe; Ghasemi Falavarjani, Majid

    2016-01-01

    The effect of air temperature, air velocity, and sample shapes (circle and square with the same cross-sectional area) on kinetic drying of potato slices in a tunnel dryer was investigated experimentally and a suitable drying model was developed. The experiments of drying of potato slices were conducted at an air temperature of 45-70°C with an air velocity 1.60 and 1.81 m sec(-1). Results showed that drying temperature was the most effective parameter in the drying rate. The influence of air velocity was more profound in low temperature. The time for drying square slices was lower compared to the circle ones. Furthermore, drying data were fitted to different empirical models. Among the models, Midilli-Kucuk was the best to explain the single layer drying of potato slices. The parameters of this model were determined as functions of air velocity and temperature by multiple regression analysis for circle and square slices. Various statistical parameters were examined for evaluating the model. PMID:26788317

  13. Cone-angle-dependent generalized weighting scheme for 16-slice helical CT

    NASA Astrophysics Data System (ADS)

    Hsieh, Jiang; Dong, Yanting; Simoni, Piero; Toth, Thomas; Slack, Christopher L.; Grekowicz, Brian; Seidenschnur, George; Shaughnessy, Charlie

    2002-05-01

    Since the recent introduction of multi-slice helical computed tomography (MHCT), new clinical applications have experienced tremendous growth in recent years. MHCT offers improved volume coverage, faster scan speed, more isotropic spatial resolution, and reduced x-ray tube loading. Similar to the single slice helical CT, the projection data collected in MHCT is inherently inconsistent due to the constant table motion. In addition, cone beam effects in MHCT produce additional complexity and image artifacts. Although the cone angle is quite smaller even for the 16-slice configuration, the impact on image artifacts cannot be ignored. Many reconstruction algorithms have been proposed and investigated recently to combat image artifacts associated with the MHCT data acquisition. In this paper, we propose a cone-angle dependent generalized weighting scheme for 16-slice helical CT that allows the production of MHCT images with only 2D backprojection. The cone-angle dependency of the algorithm suppresses image artifacts due to the cone beam effect and the generalized weighting portion enables interpolation be performed with conjugate samples for the 16-slice helical dataset. With the proposed algorithm, image artifacts are significantly reduced.

  14. A technique for slicing the rat cochlea around the onset of hearing.

    PubMed

    Jagger, D J; Robertson, D; Housley, G D

    2000-12-15

    The cochlea presents a considerable challenge to the study of sound transduction and auditory neurotransmission. This arises from the location of the sensory, supporting and secretory epithelia, and primary auditory neurons within a complex ossified spiral structure comprised of three separate fluid-filled chambers. We have developed a novel cochlear slice preparation, which provides access to the highly differentiated tissues while retaining structural integrity and cell viability. Our technique for slicing the cochlea and imaging tissue structure facilitates the study of peripheral auditory signaling in situ. The preparation was developed in the neonatal rat (postnatal days 4-14) and is based on the use of vibrating blade microtome slicing after perfusing the perilymphatic compartments with chilled Pluronic F127 NF, a block copolymer gel. This material is liquid when cold, and sets when warmed to room temperature, stabilizing the cochlear fluid-filled compartments and thereby supporting the cochlear partition during slicing. Slices (150-300 microm) of neonatal rat cochlea, imaged using infrared videomicroscopy, allow tight-seal voltage clamp recordings from a variety of cell types. Recordings obtained from primary auditory neurons, hair cells, supporting cells, and Reissner's membrane epithelial cells verify the viability of the tissues in the preparation. Data includes novel evidence for glutamatergic and purinergic co-transmission by primary auditory neurons. The preparation has considerable potential in a range of molecular physiological applications requiring cell-specific targeting with retention of cell connectivity. PMID:11163413

  15. Human Organotypic Cultured Cardiac Slices: New Platform For High Throughput Preclinical Human Trials.

    PubMed

    Kang, C; Qiao, Y; Li, G; Baechle, K; Camelliti, P; Rentschler, S; Efimov, I R

    2016-01-01

    Translation of novel therapies from bench to bedside is hampered by profound disparities between animal and human genetics and physiology. The ability to test for efficacy and cardiotoxicity in a clinically relevant human model system would enable more rapid therapy development. We have developed a preclinical platform for validation of new therapies in human heart tissue using organotypic slices isolated from donor and end-stage failing hearts. A major advantage of the slices when compared with human iPS-derived cardiomyocytes is that native tissue architecture and extracellular matrix are preserved, thereby allowing investigation of multi-cellular physiology in normal or diseased myocardium. To validate this model, we used optical mapping of transmembrane potential and calcium transients. We found that normal human electrophysiology is preserved in slice preparations when compared with intact hearts, including slices obtained from the region of the sinus node. Physiology is maintained in slices during culture, enabling testing the acute and chronic effects of pharmacological, gene, cell, optogenetic, device, and other therapies. This methodology offers a powerful high-throughput platform for assessing the physiological response of the human heart to disease and novel putative therapies. PMID:27356882

  16. On the identification of a Pliocene time slice for data–model comparison

    PubMed Central

    Haywood, Alan M.; Dolan, Aisling M.; Pickering, Steven J.; Dowsett, Harry J.; McClymont, Erin L.; Prescott, Caroline L.; Salzmann, Ulrich; Hill, Daniel J.; Hunter, Stephen J.; Lunt, Daniel J.; Pope, James O.; Valdes, Paul J.

    2013-01-01

    The characteristics of the mid-Pliocene warm period (mPWP: 3.264–3.025 Ma BP) have been examined using geological proxies and climate models. While there is agreement between models and data, details of regional climate differ. Uncertainties in prescribed forcings and in proxy data limit the utility of the interval to understand the dynamics of a warmer than present climate or evaluate models. This uncertainty comes, in part, from the reconstruction of a time slab rather than a time slice, where forcings required by climate models can be more adequately constrained. Here, we describe the rationale and approach for identifying a time slice(s) for Pliocene environmental reconstruction. A time slice centred on 3.205 Ma BP (3.204–3.207 Ma BP) has been identified as a priority for investigation. It is a warm interval characterized by a negative benthic oxygen isotope excursion (0.21–0.23‰) centred on marine isotope stage KM5c (KM5.3). It occurred during a period of orbital forcing that was very similar to present day. Climate model simulations indicate that proxy temperature estimates are unlikely to be significantly affected by orbital forcing for at least a precession cycle centred on the time slice, with the North Atlantic potentially being an important exception. PMID:24043865

  17. Flight performance and first results from the sub-orbital local interstellar cloud experiment (SLICE)

    NASA Astrophysics Data System (ADS)

    France, Kevin; Nell, Nicholas; Hoadley, Keri; Kane, Robert; Burgh, Eric B.; Beasley, Matthew; Bushinksy, Rachel; Schultz, Ted B.; Kaiser, Michael; Moore, Christopher; Kulow, Jennifer; Green, James C.

    2013-09-01

    We present the flight performance and preliminary science results from the first flight of the Sub-orbital Local Interstellar Cloud Experiment (SLICE). SLICE is a rocket-borne far-ultraviolet instrument designed to study the diffuse interstellar medium. The SLICE payload comprises a Cassegrain telescope with LiF-coated aluminum optics feeding a Rowland Circle spectrograph operating at medium resolution (R ~ 5000) over the 102 - 107 nm bandpass. We present a novel method for cleaning LiF-overcoated Al optics and the instrumental wavelength calibration, while the details of the instrument design and assembly are presented in a companion proceeding (Kane et al. 2013). We focus primarily on first results from the spring 2013 launch of SLICE in this work. SLICE was launched aboard a Terrier-Black Brant IX sounding rocket from White Sands Missile Range to observe four hot stars sampling different interstellar sightlines. The instrument acquired approximately 240 seconds of on-target time for the science spectra. We observe atomic and molecular transitions (HI, OI, CII, OVI, H2) tracing a range of temperatures, ionization states, and molecular fractions in diffuse interstellar clouds. Initial spectral synthesis results and future plans are discussed.

  18. Studies of fluid exchanges between rat liver slices and simple media.

    PubMed

    ITOH, S; SCHWARTZ, I L

    1956-11-20

    1. The exchange of fluid between slices of rat liver and solutions of monosaccharides, disaccharides, and sodium chloride has been studied in relation to the temperature of incubation. The point of apparent isotonicity (P.A.I.) of the tissue was defined as the concentration of the solution in which the slices neither gained nor lost weight after immersion for a period of 10 minutes. 2. In solutions of glucose, the P.A.I. of the slices was significantly lower at 4 degrees C. than at 20 degrees C. but similar at 20 degrees C. and 37 degrees C. Upon immersion for 15 to 60 minutes in 0.66 molar glucose the slices always swelled more at 37 degrees C. than at 20 degrees C. In solutions of sucrose change in the temperature of incubation was without effect on the hydration of the tissues. 3. In solutions of sodium chloride, the P.A.I. and the content of water, chloride, and sodium plus potassium were lower at 37 degrees C. than at 20 degrees C. 4. These findings emphasize the role of translocation of solute in providing an osmotic gradient for the movement of water between the tissue slices and the media. PMID:13385446

  19. Relationship between moisture content and electrical impedance of carrot slices during drying

    NASA Astrophysics Data System (ADS)

    Kertész, Ákos; Hlaváčová, Zuzana; Vozáry, Eszter; Staroňová, Lenka

    2015-01-01

    Electrical properties of food materials can give information about the inner structure and physiological state of biological tissues. Generally, the process of drying of fruits and vegetables is followed by weight loss. The aim of this study was to measure the impedance spectra of carrot slices during drying and to correlate impedance parameters to moisture content in different drying periods. Cylindrical slices were cut out from the carrot root along the axis. The slices were dried in a Venticell 111 air oven at 50°C. The weight of the slices was measured with a Denver SI-603 electronic analytical and precision balance. The weighing of the samples was performed every 30 min at the beginning of drying and every 60 min after the process. The moisture content of the samples was calculated on wet basis. The magnitude and phase angle of electrical impedance of the slices were measured with HP 4284A and 4285A precision LCR meters in the frequency range from 30 Hz to 1 MHz and from 75 kHz to 30 MHz, respectively, at voltage 1 V. The impedance measurement was performed after weighting. The change in the magnitude of impedance during drying showed a good correlation with the change in the moisture content.

  20. A novel dehydration technique for carrot slices implementing ultrasound and vacuum drying methods.

    PubMed

    Chen, Zhi-Gang; Guo, Xiao-Yu; Wu, Tao

    2016-05-01

    A novel drying technique using a combination of ultrasound and vacuum dehydration was developed to shorten the drying time and improve the quality of carrot slices. Carrot slices were dried with ultrasonic vacuum (USV) drying and vacuum drying at 65 °C and 75 °C. The drying rate was significantly influenced by the drying techniques and temperatures. Compared with vacuum drying, USV drying resulted in a 41-53% decrease in the drying time. The drying time for the USV and vacuum drying techniques at 75 °C was determined to be 140 and 340 min for carrot slices, respectively. The rehydration potential, nutritional value (retention of β-carotene and ascorbic acid), color, and textural properties of USV-dried carrot slices are predominately better compared to vacuum-dried carrot slices. Moreover, lower energy consumption was used in the USV technique. The drying data (time versus moisture ratio) were successfully fitted to Wang and Singh model. PMID:26703199

  1. Abscisic acid accumulation in spinach leaf slices in the presence of penetrating and nonpenetrating solutes

    SciTech Connect

    Creelman, R.A.; Zeevaart, J.A.D.

    1985-01-01

    Abscisic acid (ABA) accumulated in detached, wilted leaves of spinach (Spinacia oleracea L. cv Savoy Hybrid 612) and reached a maximum level within 3 to 4 hours. The increase in ABA over that found in detached turgid leaves was approximately 10-fold. The effects of water stress could be mimicked by the use of thin slices of spinach leaves incubated in the presence of 0.6 molar mannitol, a compound which causes plasmolysis (loss of turgor). When spinach leaf slices were incubated with ethylene glycol, a compound which rapidly penetrates the cell membrane causing a decrease in the osmotic potential of the tissue and only transient loss of turgor, no ABA accumulated. Spinach leaf slices incubated in both ethylene glycol and mannitol had ABA levels similar to those found when slices were incubated with mannitol alone. Increases similar to those found with mannitol also occurred when Aquacide III, a highly purified form of polyethylene glycol, was used. When spinach leaf slices were incubated with solutes which are supposed to disturb membrane integrity no increase in ABA was observed. These data indicate that, with respect to the accumulation of ABA, mannitol caused a physical stress rather than a chemical stress.

  2. Relation between the content of acetyl-coenzyme A and acetylcholine in brain slices.

    PubMed Central

    Rícný, J; Tucek, S

    1980-01-01

    Slices of rat caudate nuclei were incubated in vitro in media containing, among other constituents, three different concentrations of glucose (0.5, 2 and 10 mM), 0.2 mM-choline, paraoxon as an inhibitor of cholinesterase, and 5 mM- or 30 mM-K+. After 30 and 60 min of incubation, the concentrations of acetyl-CoA, acetylcholine and choline in the tissue and of acetylcholine in the incubation medium were measured. The content of acetyl-CoA in the sliced varied in direct relation to the concentration of glucose in the incubation medium. The content of acetylcholine in the slices and, in experiments with high K+, also the amount of acetylcholine released into the incubation medium varied in direct relation to the concentration of glucose in the incubation medium and to the concentration of acetyl-CoA in the slices; the relation between the concentrations of acetyl-CoA and of acetylcholine in the slices was linear. It was concluded that the availability of acetyl-CoA had a decisive influence on both the rate of synthesis of acetylcholine and its steady-state concentration. The observations accord with the view that, at the ultimate level, the synthesis of acetylcholine is controlled by the Law of Mass Action. PMID:7470027

  3. Optical properties of local surface plasmon resonance in Ag/ITO sliced nanosphere by the discrete dipole approximation

    NASA Astrophysics Data System (ADS)

    Haiwei, Mu; Jingwei, Lv; Zhaoting, Liu; Shijie, Zheng; Lin, Yang; Tao, Sun; Qiang, Liu; Chao, Liu

    2016-04-01

    Optical properties of localized surface plasmon resonances (LSPR) of Ag/ITO sliced nanosphere have been studied using discrete dipole approximation and plasmon hybridization theory. It is found that different morphologies of sliced nanosphere can induce distinctive features in the extinction spectra. In the meanwhile, gap distances and refractive index of the surrounding medium could modulate the plasmon hybridization and the LSPR shifting. At large separation, the shift of LSPR peaks for the nanosphere sliced in halves consisting of ITO and Ag is small and insensitive to the gap distance in the weak coupling, whereas smaller separation exhibits a distinct red shift. Additionally, multiple resonance peaks are excited for the nanosphere sliced in quarters consisting of ITO and Ag. In this situation, electric field is mainly distributed in the gap region of sliced nanosphere and the central point. These results indicate that different morphologies of sliced nanosphere could create abundant tunable LSPR modes, which provides potential for multiplex optical sensing.

  4. Getting a bigger slice of the pie. Effects on eating and emotion in restrained and unrestrained eaters.

    PubMed

    Polivy, Janet; Herman, C Peter; Deo, Rajbir

    2010-12-01

    Manipulated perceptions of the portion size of food influence subsequent eating by restrained and unrestrained eaters. In the present study, all participants were served a same-sized slice of pizza. For one-third of participants, their slice appeared larger than the slice being served to another ostensible participant, another third perceived their slice as smaller, and the final third did not see a second slice. All participants then proceeded to "taste and rate" cookies in an ad lib eating opportunity. A significant interaction reflected the fact that when the pizza slice was perceived as large, restrained eaters tended to eat more cookies whereas unrestrained eaters tended to eat less cookies. Emotion data suggest that the differential responses of restrained and unrestrained eaters to the belief that they have overeaten relative to another eater influenced their subsequent dissimilar ad lib eating behavior. PMID:20691231

  5. Submillimeter (Lambda < 1 mm) Continuum Imaging at CSO: A Retrospective

    NASA Technical Reports Server (NTRS)

    Dowell, C. Darren

    2009-01-01

    This contribution is submitted on behalf of all students, postdocs, and staff inspired and supported by Tom Phillips to build an instrument and then wait for low precipitable water vapor. Over the 20 plus years of its existence, the Caltech Submillimeter Observatory (CSO) has seen a succession of ever more powerful detectors to measure continuum emission in the shortest submillimeter bands available from Mauna Kea. These instruments have been trained on the nearest solar systems, the most distant galaxies, and objects in between. I show several images collected over the 5 plus year history of the SHARC II camera and anecdotal comparison with past work.

  6. The effect of ceramic thickness and number of firings on the color of a zirconium oxide based all ceramic system fabricated using CAD/CAM technology

    PubMed Central

    Aras, Meena Ajay

    2011-01-01

    PURPOSE Ceramics have a long history in fixed prosthodontics for achieving optimal esthetics and various materials have been used to improve ceramic core strength. However, there is a lack of information on how color is affected by fabrication procedure. The purpose of this study was to evaluate the effects of various dentin ceramic thicknesses and repeated firings on the color of zirconium oxide all-ceramic system (Lava™) fabricated using CAD/CAM technology. MATERIALS AND METHODS Thirty disc-shaped cores, 12 mm in diameter with a 1 mm thickness were fabricated from zirconium oxide based all ceramic systems (Lava™, 3M ESPE, St Paul, MN, USA) and divided into three groups (n = 10) according to veneering with dentin ceramic thicknesses: as 0.5, 1, or 1.5 mm. Repeated firings (3, 5, 7, or 9) were performed, and the color of the specimens was compared with the color after the initial firing. Color differences among ceramic specimens were measured using a spectrophotometer (VITA Easyshade, VITA Zahnfabrik, Bad Säckingen, Germany) and data were expressed in CIELAB system coordinates. A repeated measures ANOVA and Bonferroni post hoc test were used to analyze the data (n = 10, α=.05). RESULTS L*a*b* values of the ceramic systems were affected by the number of firings (3, 5, 7, or 9 firings) (P<.001) and ceramic thickness (0.5, 1, or 1.5 mm) (P<.001). Significant interactions were present in L*a*b* values between the number of firings and ceramic thickness (P<.001). An increase in number of firings resulted in significant increase in L* values for both 0.5 mm and 1.5 mm thicknesses (P<.01, P=.013); however it decreased for 1 mm thickness (P<.01). The a* values increased for 1 mm and 1.5 mm thicknesses (P<.01), while it decreased for 0.5 mm specimens. The b* values increased significantly for all thicknesses (P<.01, P=.022). As the dentin ceramic thickness increased, significant reductions in L* values (P<.01) were recorded. There were significant increases in both a

  7. A Hybrid Technique for Thickness-Map Visualization of the Hip Cartilages in MRI

    NASA Astrophysics Data System (ADS)

    Khanmohammadi, Mahdieh; Zoroofi, Reza Aghaiezadeh; Nishii, Takashi; Tanaka, Hisashi; Sato, Yoshinobu

    Quantification of the hip cartilages is clinically important. In this study, we propose an automatic technique for segmentation and visualization of the acetabular and femoral head cartilages based on clinically obtained multi-slice T1-weighted MR data and a hybrid approach. We follow a knowledge based approach by employing several features such as the anatomical shapes of the hip femoral and acetabular cartilages and corresponding image intensities. We estimate the center of the femoral head by a Hough transform and then automatically select the volume of interest. We then automatically segment the hip bones by a self-adaptive vector quantization technique. Next, we localize the articular central line by a modified canny edge detector based on the first and second derivative filters along the radial lines originated from the femoral head center and anatomical constraint. We then roughly segment the acetabular and femoral head cartilages using derivative images obtained in the previous step and a top-hat filter. Final masks of the acetabular and femoral head cartilages are automatically performed by employing the rough results, the estimated articular center line and the anatomical knowledge. Next, we generate a thickness map for each cartilage in the radial direction based on a Euclidian distance. Three dimensional pelvic bones, acetabular and femoral cartilages and corresponding thicknesses are overlaid and visualized. The techniques have been implemented in C++ and MATLAB environment. We have evaluated and clarified the usefulness of the proposed techniques in the presence of 40 clinical hips multi-slice MR images.

  8. Flip-angle profile of slice-selective excitation and the measurement of the MR longitudinal relaxation time with steady-state magnetization.

    PubMed

    Hsu, Jung-Jiin

    2015-08-01

    In MRI, the flip angle (FA) of slice-selective excitation is not uniform across the slice-thickness dimension. This work investigates the effect of the non-uniform FA profile on the accuracy of a commonly-used method for the measurement, in which the T1 value, i.e., the longitudinal relaxation time, is determined from the steady-state signals of an equally-spaced RF pulse train. By using the numerical solutions of the Bloch equation, it is shown that, because of the non-uniform FA profile, the outcome of the T1 measurement depends significantly on T1 of the specimen and on the FA and the inter-pulse spacing τ of the pulse train. A new method to restore the accuracy of the T1 measurement is described. Different from the existing approaches, the new method also removes the FA profile effect for the measurement of the FA, which is normally a part of the T1 measurement. In addition, the new method does not involve theoretical modeling, approximation, or modification to the underlying principle of the T1 measurement. An imaging experiment is performed, which shows that the new method can remove the FA-, the τ-, and the T1-dependence and produce T1 measurements in excellent agreement with the ones obtained from a gold standard method (the inversion-recovery method). PMID:26159799

  9. Flip-angle profile of slice-selective excitation and the measurement of the MR longitudinal relaxation time with steady-state magnetization

    NASA Astrophysics Data System (ADS)

    Hsu, Jung-Jiin

    2015-08-01

    In MRI, the flip angle (FA) of slice-selective excitation is not uniform across the slice-thickness dimension. This work investigates the effect of the non-uniform FA profile on the accuracy of a commonly-used method for the measurement, in which the T1 value, i.e., the longitudinal relaxation time, is determined from the steady-state signals of an equally-spaced RF pulse train. By using the numerical solutions of the Bloch equation, it is shown that, because of the non-uniform FA profile, the outcome of the T1 measurement depends significantly on T1 of the specimen and on the FA and the inter-pulse spacing τ of the pulse train. A new method to restore the accuracy of the T1 measurement is described. Different from the existing approaches, the new method also removes the FA profile effect for the measurement of the FA, which is normally a part of the T1 measurement. In addition, the new method does not involve theoretical modeling, approximation, or modification to the underlying principle of the T1 measurement. An imaging experiment is performed, which shows that the new method can remove the FA-, the τ-, and the T1-dependence and produce T1 measurements in excellent agreement with the ones obtained from a gold standard method (the inversion-recovery method).

  10. Performance enhancement of pre-spectrum slicing technique for wavelength conversion

    NASA Astrophysics Data System (ADS)

    Kharraz, Osayd M.; Ahmad, Harith; Mohammad, Abu Bakar B.; Forsyth, David I.; Dernaika, Mohamad; Harun, Sulaiman W.

    2015-09-01

    This paper details a proposal and successful demonstration of an ultra-narrow and very high optical signal-to-noise ratio wavelength converted channel that was generated from an efficient ultra-narrow pre-spectrum sliced probe channel via four-wave mixing in a highly non-linear fiber medium. An array of narrowband fiber Bragg grating filters acted as a discriminative component to pre-spectrum slice the probe channel from backward amplified spontaneous emission, which, in turn, induced an additional fiber Bragg grating filtering mechanism within an erbium-doped fiber medium in a saturable configuration. A resultant optical signal-to-noise ratio of more than 70 dB in the probe channel gave rise to a 40 dB optical signal-to-noise ratio in the converted channel. These outcomes indicate the proposed scheme is highly suitable for practical, cost-effective wavelength conversion in any "pre-spectrum sliced" optical communication system.

  11. Imaging of molecular surface dynamics in brain slices using single-particle tracking

    PubMed Central

    Biermann, B.; Sokoll, S.; Klueva, J.; Missler, M.; Wiegert, J. S.; Sibarita, J. -B.; Heine, M.

    2014-01-01

    Organization of signalling molecules in biological membranes is crucial for cellular communication. Many receptors, ion channels and cell adhesion molecules are associated with proteins important for their trafficking, surface localization or function. These complexes are embedded in a lipid environment of varying composition. Binding affinities and stoichiometry of such complexes were so far experimentally accessible only in isolated systems or monolayers of cell culture. Visualization of molecular dynamics within signalling complexes and their correlation to specialized membrane compartments demand high temporal and spatial resolution and has been difficult to demonstrate in complex tissue like brain slices. Here we demonstrate the feasibility of single-particle tracking (SPT) in organotypic brain slices to measure molecular dynamics of lipids and transmembrane proteins in correlation to synaptic membrane compartments. This method will provide important information about the dynamics and organization of surface molecules in the complex environment of neuronal networks within brain slices. PMID:24429796

  12. Microbial growth and sensory quality of dried potato slices irradiated by electrons

    NASA Astrophysics Data System (ADS)

    Kim, Hyun-Jin; Song, Hyeon-Jeong; Song, Kyung-Bin

    2011-06-01

    Electron beam irradiation was applied to secure the microbial safety of dried purple sweet potato. After purple sweet potato slices had been dehydrated with 20% (w/w) maltodextrin solution, the samples were irradiated at doses 2, 4, 6, 8, and 10 kGy and then stored at 20 °C for 60 days. Microbiological data indicated that the populations of total aerobic bacteria and of yeast and molds significantly decreased with increase in irradiation dosage. Specifically, microbial load was reduced by about three log cycles at 6 kGy compared to those of the control. Based on the color measurement of the potato slices, electron beam irradiation treatment did not affect the color quality. Sensory evaluation results also showed that electron beam irradiation did not affect overall sensory scores during storage. These results suggest that electron beam irradiation could be useful for improving microbial safety without impairing the quality of the potato slices during storage.

  13. Effects of pretreatments on the diffusion kinetics and some quality parameters of osmotically dehydrated apple slices.

    PubMed

    Taiwo, K A; Angersbach, A; Ade-Omowaye, B I; Knorr, D

    2001-06-01

    This study compared mass transfer during osmotic dehydration (OD) and some quality indices of untreated apple slices to those of apple slices pretreated by either blanching, freezing, or applying high-intensity electric field pulses (HELP) or high pressure (HP). HP, HELP, and blanching increased water loss. Untreated and HELP-treated samples had comparable solids gains, which were lower (P < 0.05) than in the other samples. Apple slices turned brown after pretreatment but the L values of these samples increased with OD. The breaking force of dried samples increased with OD time, and pretreated samples had firmer dried texture than the untreated. Vitamin C content decreased with OD time, but HP- and HELP-treated apples had better retention of vitamin C. PMID:11409969

  14. Grid Cell Responses in 1D Environments Assessed as Slices through a 2D Lattice.

    PubMed

    Yoon, KiJung; Lewallen, Sam; Kinkhabwala, Amina A; Tank, David W; Fiete, Ila R

    2016-03-01

    Grid cells, defined by their striking periodic spatial responses in open 2D arenas, appear to respond differently on 1D tracks: the multiple response fields are not periodically arranged, peak amplitudes vary across fields, and the mean spacing between fields is larger than in 2D environments. We ask whether such 1D responses are consistent with the system's 2D dynamics. Combining analytical and numerical methods, we show that the 1D responses of grid cells with stable 1D fields are consistent with a linear slice through a 2D triangular lattice. Further, the 1D responses of comodular cells are well described by parallel slices, and the offsets in the starting points of the 1D slices can predict the measured 2D relative spatial phase between the cells. From these results, we conclude that the 2D dynamics of these cells is preserved in 1D, suggesting a common computation during both types of navigation behavior. PMID:26898777

  15. Thermal dependence of neural activity in the hamster hippocampal slice preparation

    NASA Technical Reports Server (NTRS)

    Horowitz, J. M.; Thomas, M. P.; Eckerman, P.

    1987-01-01

    1. Neural activity was recorded in an in vitro hamster hippocampal slice preparation while the temperature of the Ringer's solution bathing in the slice was controlled at selected levels. 2. The amplitude of the population spike (action potentials from a group of pyramidal cells) was measured as bath temperature was lowered from 35 degrees C to temperatures where a response could not be evoked. 3. Plots of population spike amplitude versus temperature have bell-shaped curves. The population spikes increased in amplitude as temperature was lowered from 35 degrees C, reached a peak amplitude between 25 and 20 degrees C, and then decreased until a response could not be evoked when temperature was further lowered. 4. These in vitro results obtained in the slice preparation are related to in vivo hippocampal studies. Results are interpreted as consistent with the proposal reviewed here that neural activity in the hippocampus plays a role at specific stages of entrance into and arousal from hibernation.

  16. Control of enzymatic browning in apple slices by using ascorbic acid under different conditions.

    PubMed

    el-Shimi, N M

    1993-01-01

    Control of phenol oxidase activity in apple slices by the use of ascorbic acid at different pH values, temperature and time of incubation was investigated. The enzyme was almost inactivated at 1% and 1.5% ascorbic acid. Ascorbic acid solution (1%) caused a remarkable inhibition with the increasing acidity up to pH = 1. Heating treatments for apple slices dipped in 1% ascorbic acid caused a reduction of enzymatic browning, optimum temperature for inactivation of the enzyme was between 60-70 degrees C for 15 minutes. Increasing the time of dipping apple slices in 1% ascorbic acid solutions and at different pH values reduce phenolase activity. PMID:8464847

  17. Economics of ingot slicing with an internal diameter saw for low-cost solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Liu, J. K.; Fiegl, G.

    1981-01-01

    Slicing of silicon ingots using diamond impregnated internal diameter blade saws has been a standard technology of the semiconductor industry. This paper describes work on improvements to this technology for 10 cm diameter ingot slicing. Ingot rotation, dynamic blade edge control with feedback, mechanized blade dressing and development of thinner blades are the approaches tried. A comparison of the results for wafering with and without ingot rotation is also made. A sensitivity analysis of the major cost elements in wafering is performed for 10 cm diameter ingot and extended to the 15 cm diameter ingot case. Various parameter values such as machine cost, feed rate and consumable materials cost are identified both for single and multiple ingot slicing.

  18. MRI Slice Segmentation and 3D Modelling of Temporomandibular Joint Measured by Microscopic Coil

    NASA Astrophysics Data System (ADS)

    Smirg, O.; Liberda, O.; Smekal, Z.; Sprlakova-Pukova, A.

    2012-01-01

    The paper focuses on the segmentation of magnetic resonance imaging (MRI) slices and 3D modelling of the temporomandibular joint disc in order to help physicians diagnose patients with dysfunction of the temporomandibular joint (TMJ). The TMJ is one of the most complex joints in the human body. The most common joint dysfunction is due to the disc. The disc is a soft tissue, which in principle cannot be diagnosed by the CT method. Therefore, a 3D model is made from the MRI slices, which can image soft tissues. For the segmentation of the disc in individual slices a new method is developed based on spatial distribution and anatomical TMJ structure with automatic thresholding. The thresholding is controlled by a genetic algorithm. The 3D model is realized using the marching cube method.

  19. Adaptation of Microplate-based Respirometry for Hippocampal Slices and Analysis of Respiratory Capacity

    PubMed Central

    Schuh, Rosemary A.; Clerc, Pascaline; Hwang, Hyehyun; Mehrabian, Zara; Bittman, Kevin; Chen, Hegang; Polster, Brian M.

    2011-01-01

    Multiple neurodegenerative disorders are associated with altered mitochondrial bioenergetics. Although mitochondrial O2 consumption is frequently measured in isolated mitochondria, isolated synaptic nerve terminals (synaptosomes), or cultured cells, the absence of mature brain circuitry is a remaining limitation. Here we describe the development of a method that adapts the Seahorse Extracellular Flux Analyzer (XF24) for the microplate-based measurement of hippocampal slice O2 consumption. As a first evaluation of the technique, we compared whole slice bioenergetics to previous measurements made with synaptosomes or cultured neurons. We found that mitochondrial respiratory capacity and O2 consumption coupled to ATP synthesis could be estimated in cultured or acute hippocampal slices with preserved neural architecture. Mouse organotypic hippocampal slices oxidizing glucose displayed mitochondrial O2 consumption that was well-coupled, as determined by the sensitivity to the ATP synthase inhibitor oligomycin. However stimulation of respiration by uncoupler was modest (<120% of basal respiration) compared to previous measurements in cells or synaptosomes, although enhanced slightly (to ~150% of basal respiration) by the acute addition of the mitochondrial complex I-linked substrate pyruvate. These findings suggest a high basal utilization of respiratory capacity in slices and a limitation of glucose-derived substrate for maximal respiration. The improved throughput of microplate-based hippocampal respirometry over traditional O2 electrode-based methods is conducive to neuroprotective drug screening. When coupled with cell type-specific pharmacology or genetic manipulations, the ability to efficiently measure O2 consumption from whole slices should advance our understanding of mitochondrial roles in physiology and neuropathology. PMID:21520220

  20. Slicing Method for curved façade and window extraction from point clouds

    NASA Astrophysics Data System (ADS)

    Iman Zolanvari, S. M.; Laefer, Debra F.

    2016-09-01

    Laser scanning technology is a fast and reliable method to survey structures. However, the automatic conversion of such data into solid models for computation remains a major challenge, especially where non-rectilinear features are present. Since, openings and the overall dimensions of the buildings are the most critical elements in computational models for structural analysis, this article introduces the Slicing Method as a new, computationally-efficient method for extracting overall façade and window boundary points for reconstructing a façade into a geometry compatible for computational modelling. After finding a principal plane, the technique slices a façade into limited portions, with each slice representing a unique, imaginary section passing through a building. This is done along a façade's principal axes to segregate window and door openings from structural portions of the load-bearing masonry walls. The method detects each opening area's boundaries, as well as the overall boundary of the façade, in part, by using a one-dimensional projection to accelerate processing. Slices were optimised as 14.3 slices per vertical metre of building and 25 slices per horizontal metre of building, irrespective of building configuration or complexity. The proposed procedure was validated by its application to three highly decorative, historic brick buildings. Accuracy in excess of 93% was achieved with no manual intervention on highly complex buildings and nearly 100% on simple ones. Furthermore, computational times were less than 3 sec for data sets up to 2.6 million points, while similar existing approaches required more than 16 hr for such datasets.

  1. Influence of Verapamil and Cyclosporin A on bile acid metabolism and transport in rat liver slices.

    PubMed

    Barth, Astrid; Braun, Jerome; Müller, Dieter

    2006-08-01

    Verapamil (V) is a specific inhibitor of the P-glycoprotein (mdr1) in the hepatocyte canalicular membrane. Cyclosporin A (CsA) as an essential immunosuppressive drug has potentially cholestatic adverse effects on the liver, but increases the expression of mdr1. In precision-cut liver slices from 34- to 40-day-old male Wistar rats 26 individual free and conjugated bile acids (BAs) as markers of hepatic transport and synthesis function were analysed after 4 h incubation with V (100 microM) or CsA (5 microM) in Krebs-Henseleit buffer. Some slices were loaded with cholic acid (CA 5 microM) or tauro-ursodeoxycholic acid (T-UDCA 5 microM) to investigate the V and CsA effects under conditions of BA supplementation. BAs were determined in tissue and medium by HPLC with postcolumn derivatisation and fluorescence detection. V and CsA, influencing different targets in BA transport, enhanced slice concentrations of T- and glyco- (G-) conjugated CA only when exogenous CA was given additionally. This BA accumulation in tissue is more reflected at decreased medium concentrations of these BAs after V and CsA incubations. Both V and CsA also inhibited CA uptake into the slices. The acidic chenodeoxycholic acid (CDCA) synthesis pathway is disturbed: T- and G-CDCA concentrations are diminished in slices and medium after V and CsA incubations. T-UDCA plus V or CsA enhanced not only its own slice concentration but also the concentration of the trihydroxylated tauro-muricholic acid (T-beta-MCA), reflecting the conversion of the accumulated dihydroxylated T-UDCA into the T-beta-MCA. The similar effects of V and CsA on BA transport and metabolism can be explained by mdr1 mediated disturbances of cellular ATP transport rather than by inhibition of individual BA transporters. PMID:16793245

  2. Coronary Stent Artifact Reduction with an Edge-Enhancing Reconstruction Kernel – A Prospective Cross-Sectional Study with 256-Slice CT

    PubMed Central

    Tan, Stéphanie; Soulez, Gilles; Diez Martinez, Patricia; Larrivée, Sandra; Stevens, Louis-Mathieu; Goussard, Yves; Mansour, Samer; Chartrand-Lefebvre, Carl

    2016-01-01

    Purpose Metallic artifacts can result in an artificial thickening of the coronary stent wall which can significantly impair computed tomography (CT) imaging in patients with coronary stents. The objective of this study is to assess in vivo visualization of coronary stent wall and lumen with an edge-enhancing CT reconstruction kernel, as compared to a standard kernel. Methods This is a prospective cross-sectional study involving the assessment of 71 coronary stents (24 patients), with blinded observers. After 256-slice CT angiography, image reconstruction was done with medium-smooth and edge-enhancing kernels. Stent wall thickness was measured with both orthogonal and circumference methods, averaging thickness from diameter and circumference measurements, respectively. Image quality was assessed quantitatively using objective parameters (noise, signal to noise (SNR) and contrast to noise (CNR) ratios), as well as visually using a 5-point Likert scale. Results Stent wall thickness was decreased with the edge-enhancing kernel in comparison to the standard kernel, either with the orthogonal (0.97 ± 0.02 versus 1.09 ± 0.03 mm, respectively; p<0.001) or the circumference method (1.13 ± 0.02 versus 1.21 ± 0.02 mm, respectively; p = 0.001). The edge-enhancing kernel generated less overestimation from nominal thickness compared to the standard kernel, both with the orthogonal (0.89 ± 0.19 versus 1.00 ± 0.26 mm, respectively; p<0.001) and the circumference (1.06 ± 0.26 versus 1.13 ± 0.31 mm, respectively; p = 0.005) methods. The edge-enhancing kernel was associated with lower SNR and CNR, as well as higher background noise (all p < 0.001), in comparison to the medium-smooth kernel. Stent visual scores were higher with the edge-enhancing kernel (p<0.001). Conclusion In vivo 256-slice CT assessment of coronary stents shows that the edge-enhancing CT reconstruction kernel generates thinner stent walls, less overestimation from nominal thickness, and better image quality

  3. Tailored slice selection in solid-state MRI by DANTE under magic-echo line narrowing

    NASA Astrophysics Data System (ADS)

    Matsui, Shigeru; Masumoto, Hidefumi; Hashimoto, Takeyuki

    2007-06-01

    We propose a method of slice selection in solid-state MRI by combining DANTE selective excitation with magic-echo (ME) line narrowing. The DANTE RF pulses applied at the ME peaks practically do not interfere with the ME line narrowing in the combined ME DANTE sequence. This allows straightforward tailoring of the slice profile simply by introducing an appropriate modulation, such as a sinc modulation, into the flip angles of the applied DANTE RF pulses. The utility of the method has been demonstrated by preliminary experiments performed on a test sample of adamantane.

  4. Ultra-fast MRI of the human brain with simultaneous multi-slice imaging

    NASA Astrophysics Data System (ADS)

    Feinberg, David A.; Setsompop, Kawin

    2013-04-01

    The recent advancement of simultaneous multi-slice imaging using multiband excitation has dramatically reduced the scan time of the brain. The evolution of this parallel imaging technique began over a decade ago and through recent sequence improvements has reduced the acquisition time of multi-slice EPI by over ten fold. This technique has recently become extremely useful for (i) functional MRI studies improving the statistical definition of neuronal networks, and (ii) diffusion based fiber tractography to visualize structural connections in the human brain. Several applications and evaluations are underway which show promise for this family of fast imaging sequences.

  5. Simulated ischaemia-reperfusion conditions increase xanthine dehydrogenase and oxidase activities in rat brain slices.

    PubMed

    Battelli, M G; Buonamici, L; Virgili, M; Abbondanza, A; Contestabile, A

    1998-01-01

    Xanthine dehydrogenase and oxidase activities increased by 87% in rat brain slices after 30 min in vitro ischaemia. A further 41% increase was induced by 30 min simulated reperfusion of ischaemic slices. No conversion from the dehydrogenase to the oxidase activity was observed. The increment of enzyme activity was not due to neosynthesis of the enzyme, since it was not affected by the addition of cycloheximide during the ischaemic incubation. The increased oxygen-dependent form of the enzyme could aggravate the ischaemic brain injury by free radicals production, in particular after reperfusion. PMID:9460697

  6. Global Free Tropospheric NO2 Abundances Derived Using a Cloud Slicing Technique Applied to Satellite Observations from the Aura Ozone Monitoring Instrument (OMI)

    NASA Technical Reports Server (NTRS)

    Choi, S.; Joiner, J.; Choi, Y.; Duncan, B. N.; Bucsela, E.

    2014-01-01

    We derive free-tropospheric NO2 volume mixing ratios (VMRs) and stratospheric column amounts of NO2 by applying a cloud slicing technique to data from the Ozone Monitoring Instrument (OMI) on the Aura satellite. In the cloud-slicing approach, the slope of the above-cloud NO2 column versus the cloud scene pressure is proportional to the NO2 VMR. In this work, we use a sample of nearby OMI pixel data from a single orbit for the linear fit. The OMI data include cloud scene pressures from the rotational-Raman algorithm and above-cloud NO2 vertical column density (VCD) (defined as the NO2 column from the cloud scene pressure to the top-of-the-atmosphere) from a differential optical absorption spectroscopy (DOAS) algorithm. Estimates of stratospheric column NO2 are obtained by extrapolating the linear fits to the tropopause. We compare OMI-derived NO2 VMRs with in situ aircraft profiles measured during the NASA Intercontinental Chemical Transport Experiment Phase B (INTEX-B) campaign in 2006. The agreement is generally within the estimated uncertainties when appropriate data screening is applied. We then derive a global seasonal climatology of free-tropospheric NO2 VMR in cloudy conditions. Enhanced NO2 in the free troposphere commonly appears near polluted urban locations where NO2 produced in the boundary layer may be transported vertically out of the boundary layer and then horizontally away from the source. Signatures of lightning NO2 are also shown throughout low and middle latitude regions in summer months. A profile analysis of our cloud slicing data indicates signatures of uplifted and transported anthropogenic NO2 in the middle troposphere as well as lightning-generated NO2 in the upper troposphere. Comparison of the climatology with simulations from the Global Modeling Initiative (GMI) for cloudy conditions (cloud optical thicknesses > 10) shows similarities in the spatial patterns of continental pollution outflow. However, there are also some differences in

  7. Association of Increased Epicardial Adipose Tissue Thickness With Adverse Cardiovascular Outcomes in Patients With Atrial Fibrillation

    PubMed Central

    Chu, Chun-Yuan; Lee, Wen-Hsien; Hsu, Po-Chao; Lee, Meng-Kuang; Lee, Hung-Hao; Chiu, Cheng-An; Lin, Tsung-Hsien; Lee, Chee-Siong; Yen, Hsueh-Wei; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung; Su, Ho-Ming

    2016-01-01

    Abstract The thickness of epicardial adipose tissue (EAT) was reported to be highly associated with the incidence and severity of atrial fibrillation (AF). This study was conducted to analyze the ability of EAT thickness in predicting adverse cardiovascular (CV) events in AF. In 190 persistent AF patients, we performed a comprehensive transthoracic echocardiographic examination with assessment of EAT thickness. The definition of CV events included CV mortality, hospitalization for heart failure, myocardial infarction, and stroke. There were 69 CV events including 19 CV deaths, 32 hospitalizations for heart failure, 3 myocardial infarctions, and 15 strokes during a mean follow-up of 29 (25th–75th percentile: 17–36) months. The multivariable analysis demonstrates that chronic heart failure, increased left ventricular (LV) mass index and the ratio of transmitral E-wave velocity to early diastolic mitral annulus velocity, decreased body mass index, and increased EAT thickness (per 1-mm increase, odds ratio 1.224, 95% confidence interval [CI] 1.096–1.368, P < 0.001) were associated with adverse CV events. Additionally, the addition of EAT thickness to a model containing CHA2DS2-VASc score, left atrial volume index, and LV systolic and diastolic function significantly improved the values in predicting CV events (global χ2 increase 14.65, P < 0.001 and integrated discrimination improvement 0.10, 95% CI 0.04–0.16, P < 0.001). In AF, EAT thickness was useful in predicting adverse CV events. Additionally, EAT thickness could provide incremental value for CV outcome prediction over traditional clinical and echocardiographic parameters in AF. PMID:26986099

  8. Association of Increased Epicardial Adipose Tissue Thickness With Adverse Cardiovascular Outcomes in Patients With Atrial Fibrillation.

    PubMed

    Chu, Chun-Yuan; Lee, Wen-Hsien; Hsu, Po-Chao; Lee, Meng-Kuang; Lee, Hung-Hao; Chiu, Cheng-An; Lin, Tsung-Hsien; Lee, Chee-Siong; Yen, Hsueh-Wei; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung; Su, Ho-Ming

    2016-03-01

    The thickness of epicardial adipose tissue (EAT) was reported to be highly associated with the incidence and severity of atrial fibrillation (AF). This study was conducted to analyze the ability of EAT thickness in predicting adverse cardiovascular (CV) events in AF.In 190 persistent AF patients, we performed a comprehensive transthoracic echocardiographic examination with assessment of EAT thickness. The definition of CV events included CV mortality, hospitalization for heart failure, myocardial infarction, and stroke.There were 69 CV events including 19 CV deaths, 32 hospitalizations for heart failure, 3 myocardial infarctions, and 15 strokes during a mean follow-up of 29 (25th-75th percentile: 17-36) months. The multivariable analysis demonstrates that chronic heart failure, increased left ventricular (LV) mass index and the ratio of transmitral E-wave velocity to early diastolic mitral annulus velocity, decreased body mass index, and increased EAT thickness (per 1-mm increase, odds ratio 1.224, 95% confidence interval [CI] 1.096-1.368, P < 0.001) were associated with adverse CV events. Additionally, the addition of EAT thickness to a model containing CHA2DS2-VASc score, left atrial volume index, and LV systolic and diastolic function significantly improved the values in predicting CV events (global χ increase 14.65, P < 0.001 and integrated discrimination improvement 0.10, 95% CI 0.04-0.16, P < 0.001).In AF, EAT thickness was useful in predicting adverse CV events. Additionally, EAT thickness could provide incremental value for CV outcome prediction over traditional clinical and echocardiographic parameters in AF. PMID:26986099

  9. Translucency and Masking Ability of Various Composite Resins at Different Thicknesses

    PubMed Central

    Darabi, Farideh; Radafshar, Golpar; Tavangar, Maryam; Davaloo, Reza; Khosravian, Aref; Mirfarhadi, Nastaran

    2014-01-01

    Statement of the Problem: Optical properties of the composite resins, concerning their translucency and thickness, are affected by discolored tooth structure or inherent darkness of the oral cavity. Purpose: This study aimed to compare the translucency parameter (TP) of five different composite resins in different thicknesses and to evaluate their masking ability in black backgrounds. Materials and Method: Five brands of composite resins; Gradia (GC) and Crystalline (Confi-dental) in opaque A2 (OA2), Vit-l-escence (Ultradent) in opaque snow (OS), Herculite XRV (Kerr) and Opallis (FGM) in dentin A2 (DA2) shades were selected to enroll the study. Color coordinates of each composite were determined at 0.5, 1, and 1.5 mm thicknesses on a white backing, the backing of material itself and a black backing were calculated by using a spectrophotometer to evaluate the translucency parameter (TP) of the study materials. The masking ability was also calculated from the specimens on the material itself and on black backing. The values under 2 were estimated as imperceptible. One-way ANOVA, T-test and Tukey HSD were employed for statistical analysis. Results: The masking ability values, recorded for the 1.5 mm-thick specimens, were in the range of imperceptible except for the Herculite. There was no difference in TP values of the materials at 1.5 mm thickness. Opaque snow shade of Vit-l-escence and opaque A2 shade of Gradia showed lower TP values in comparison with the other 1 and 0.5 mm-thick materials and this difference was statistically significant (p< 0.05). Conclusion: In relatively thin thicknesses (≤1mm), these opaque/dentin shade composite resins could not mask the black background color. PMID:25191660

  10. Slicing The 2010 Saturn's Storm: Upper Clouds And Hazes

    NASA Astrophysics Data System (ADS)

    Perez-Hoyos, Santiago; Sanz-Requena, J. F.; Sanchez-Lavega, A.; Hueso, R.

    2012-10-01

    At the end of 2010 a small storm erupted in Saturn's northern mid-latitudes. Starting from a localized perturbation, it grew up to be a global-scale disturbance and cover the whole latitude band by February, 2011 (Fletcher et al. 2011, Science 332; Sánchez-Lavega et al. 2011, Nature 475; Fischer et al. 2011, Nature 475). By June, 2011 the storm was facing its end and gradually disappeared (Sánchez-Lavega et al. 2012, Icarus 220). In this work we use the observations acquired by the Cassini ISS instrument during the whole process to investigate the vertical cloud and haze structure above the ammonia condensation level (roughly 1 bar). Cassini ISS observations cover visual wavelengths from the blue to the near-infrared including two methane absorption bands. Such observations have been modeled using a radiative transfer code which reproduces the atmospheric reflectivity as a function of observation/illumination geometry and wavelength together with a retrieval technique to find maximum likelihood atmospheric models. This allows to investigate some atmospheric parameters: cloud-top pressures, aerosol optical thickness and particle absorption, among others. We will focus on two aspects: (1) maximum likelihood models for the undisturbed reference atmosphere in the 15°N to 45°N band before and after the disturbance; (2) models for particular structures during the development of the global-scale phenomenon. Our results show a general increase of particle density and single-scattering albedo inside the storm. However, some discrete features showing anomalous structure and related to the storm peculiar dynamics will also be discussed. Acknowledgments: This work was supported by the Spanish MICIIN project AYA2009-10701 with FEDER funds, by Grupos Gobierno Vasco IT-464-07 and by Universidad País Vasco UPV/EHU through program UFI11/55.

  11. Domain formation and polarization reversal under atomic force microscopy-tip voltages in ion-sliced LiNbO{sub 3} films on SiO{sub 2}/LiNbO{sub 3} substrates

    SciTech Connect

    Gainutdinov, R. V.; Volk, T. R.; Zhang, H. H.

    2015-10-19

    We report on studies on writing of micro- and nanodomains and specified domain patterns by AFM-tip voltages U{sub DC} in thin (0.5 μm thick) ion-sliced LiNbO{sub 3} films embedded to SiO{sub 2}/LiNbO{sub 3} substrates. A peculiar feature is an overlapping of domains as the distance between them decreases. Piezoelectric hysteresis loops were measured in a wide range of U{sub DC} pulse durations. Domain dynamics and characteristics of hysteresis loops reveal marked distinctions from those observed so far in LiNbO{sub 3} films and bulk crystals.

  12. Lipid peroxidation measured as thiobarbituric acid-reactive substances in tissue slices: characterization and comparison with homogenates and microsomes.

    PubMed

    Fraga, C G; Leibovitz, B E; Tappel, A L

    1988-01-01

    Liver slices were used to measure lipid peroxidation induced by bromotrichloromethane, tert-butyl hydroperoxide (t-BOOH), or ferrous iron. The responses of liver homogenates and microsomes to oxidative conditions were compared with the response of tissue slices. Lipid peroxidation was evaluated by the production of thiobarbituric acid-reactive substances (TBARS). As was observed in homogenates and microsomes, TBARS production by liver slices depended upon the amount of tissue, the incubation time, inducer, the amount of inducer, and the presence of antioxidant. Control liver slices incubated at 37 degrees C for 2 h produced 19 nmol of TBARS per g of liver. When slices were incubated in the presence of 1 mM BrCCl3, 1 mM t-BOOH, or 50 microM ferrous iron, TBARS production increased 4.6-, 8.2-, or 6.7-fold over the control value, respectively. Comparable induction of TBARS by liver homogenates and microsomes was observed when these preparations were incubated with the same inducers. Addition of 5 microM butylated hydroxytoluene (BHT) prevented the induction of TBARS by 50 microM ferrous iron by liver slices. The results indicate the usefulness of tissue slices to measure lipid peroxidation. The usefulness of tissue slices is emphasized when a number of compounds or tissues are studied and tissue integrity is desired as in toxicological, pharmacological, and nutritional studies where reduced numbers of experimental animals is a relevant issue. PMID:3356355

  13. Processing and quality characteristics of apple slices under simultaneous infrared dry-blanching and dehydration with continuous heating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated the effects of various processing parameters on apple slices exposed to infrared (IR) radiation heating in a continuous heating mode for achieving simultaneous infrared dry-blanching and dehydration (SIRDBD). The investigated parameters were radiation intensity, slice thickne...

  14. Processing and Quality Characteristics of Apple Slices under Simultaneous Infrared Dry-Blanching and Dehydration with Continuous Heating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated the effects of various processing parameters on apple slices exposed to infrared (IR) radiation heating in a continuous heating mode for achieving simultaneous infrared dry-blanching and dehydration (SIRDBD). The parameters studied included radiation intensity, slice thickne...

  15. Using a high-speed movie camera to evaluate slice dropping in clinical image interpretation with stack mode viewers.

    PubMed

    Yakami, Masahiro; Yamamoto, Akira; Yanagisawa, Morio; Sekiguchi, Hiroyuki; Kubo, Takeshi; Togashi, Kaori

    2013-06-01

    The purpose of this study is to verify objectively the rate of slice omission during paging on picture archiving and communication system (PACS) viewers by recording the images shown on the computer displays of these viewers with a high-speed movie camera. This study was approved by the institutional review board. A sequential number from 1 to 250 was superimposed on each slice of a series of clinical Digital Imaging and Communication in Medicine (DICOM) data. The slices were displayed using several DICOM viewers, including in-house developed freeware and clinical PACS viewers. The freeware viewer and one of the clinical PACS viewers included functions to prevent slice dropping. The series was displayed in stack mode and paged in both automatic and manual paging modes. The display was recorded with a high-speed movie camera and played back at a slow speed to check whether slices were dropped. The paging speeds were also measured. With a paging speed faster than half the refresh rate of the display, some viewers dropped up to 52.4 % of the slices, while other well-designed viewers did not, if used with the correct settings. Slice dropping during paging was objectively confirmed using a high-speed movie camera. To prevent slice dropping, the viewer must be specially designed for the purpose and must be used with the correct settings, or the paging speed must be slower than half of the display refresh rate. PMID:23053908

  16. Self-Mixing Thin-Slice Solid-State Laser Metrology

    PubMed Central

    Otsuka, Kenju

    2011-01-01

    This paper reviews the dynamic effect of thin-slice solid-state lasers subjected to frequency-shifted optical feedback, which led to the discovery of the self-mixing modulation effect, and its applications to quantum-noise-limited versatile laser metrology systems with extreme optical sensitivity. PMID:22319406

  17. EFFICACY OF SODIUM CHLORITE AS AN INHIBITOR OF ENZYMATIC BROWNING IN APPLE SLICES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sodium chlorite (SC) is an effective sanitizer for inhibiting microbial growth. This investigation was conducted to determine the efficacy of SC as a browning control agent for use on fresh-cut apple slices, applied alone, or in conjunction with organic acids. Additionally, the authors compared the ...

  18. Comparisons between complete and slice finite element models of a multiple arch and Buttress Dam

    SciTech Connect

    Nuss, L.K.

    1995-12-31

    Multiple arch and buttress dams are very complex structures commonly requiring analysis by finite element methods for seismic structural evaluation. Complete 3-dimensional finite element models are very expensive and time consuming. Therefore, simplified finite element models, which analyze only a portion or {open_quotes}slice{close_quotes} of the dam, are considered as a possible cost- and time-saving tool. A slice model includes only a repeatable and analytical representative section of buttresses and arches. Simplifying the analyses requires assumptions concerning the restraint conditions along the finite element boundaries, the portion of the dam to model, and the expanse of the model. These assumptions are critically important for obtaining reliable results from the analyses since the critical motion during an earthquake is in the cross-canyon direction of a multiple arch and buttress dam. Incorrect modeling of the slice model could induce too much restraint and produce unreliable results. This paper will compare the dynamic frequency, displacement, and stress results obtained from complete and slice finite element models.

  19. Distortion-free spectrum sliced microwave photonic signal processor: analysis, design and implementation.

    PubMed

    Li, Liwei; Yi, Xiaoke; Huang, Thomas X H; Minasian, Robert A

    2012-05-01

    A new switchable microwave photonic filter based on a novel spectrum slicing technique is presented. The processor enables programmable multi-tap generation with general transfer function characteristics and offers tunability, reconfigurabiliy, and switchability. It is based on connecting a dispersion controlled spectrum slicing filter after the modulated bipolar broadband light source, which consequently generates multiple spectrum slices with bipolarity, and compensates dispersion induced RF degradation simultaneously within a single device. A detailed theoretical model for this microwave photonic filter design is presented. Experimental results are presented which verify the model, and demonstrate a 33 bipolar-tap microwave filter with significant reduction of passband attenuations at high frequencies. The RF response improvement of the new microwave photonic filter is investigated, for both an ideal linear group delay line and for the experimental fiber delay line that has second order group delay and the results show that this new structure is effective for RF filters with various free spectral range values and spectrum slice bandwidths. Finally, a switchable bipolar filter that has a square-top bandpass filter response with more than 30 dB stopband attenuation that can be switched on/off via software control is demonstrated. PMID:22565771

  20. Tunicamycin produces TDP-43 cytoplasmic inclusions in cultured brain organotypic slices.

    PubMed

    Leggett, Cadman; McGehee, Daniel S; Mastrianni, James; Yang, Wenbin; Bai, Tao; Brorson, James R

    2012-06-15

    The cellular distribution of TAR DNA binding protein (TDP-43) is disrupted in several neurodegenerative disorders, including frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U subtype) and amyotrophic lateral sclerosis (ALS). In these conditions, TDP-43 is found in neuronal cytoplasmic inclusions, with loss of the normal nuclear expression. The mechanisms leading to TDP-43 redistribution and its role in disease pathophysiology remain unknown. We describe an in vitro neural tissue model that reproduces TDP-43 relocalization and inclusion formation. Two week-old coronal organotypic mouse brain slice cultures were treated with tunicamycin for 7 days. In cortical regions of treated slice cultures, cytoplasmic inclusions of TDP-43 immunoreactivity were observed, with loss of nuclear TDP-43 immunoreactivity. These inclusions were found in both astrocytes and neurons, and were of both skein-like and round morphologies. In contrast, TDP-43 cytoplasmic inclusions were not found in slices treated with staurosporine to induce apoptosis, or with trans-4-carboxy-l-proline (PDC) to induce chronic glutamate excitotoxicity. Furthermore, TDP-43 cytoplasmic inclusions did not co-localize with cleaved caspase-3, suggesting that TDP-43 mislocalization does not generally accompany caspase activation or apoptosis. The induction of TDP-43 cytoplasmic translocation in cerebrocortical slice cultures by tunicamycin provides a platform for further mechanistic investigations of pathological processing of TDP-43. PMID:22459357

  1. Hydrogen sulfide inhibits enzymatic browning of fresh-cut lotus root slices by regulating phenolic metabolism.

    PubMed

    Sun, Ying; Zhang, Wei; Zeng, Tao; Nie, Qixing; Zhang, Fengying; Zhu, Liqin

    2015-06-15

    The effect of fumigation with hydrogen sulfide (H2S) gas on inhibiting enzymatic browning of fresh-cut lotus root slices was investigated. Browning degree, changes in color, total phenol content, superoxide anion production rate (O2(-)), H2O2 content, antioxidant capacities (DPPH radical scavenging ability, ABTS radical scavenging activity and the reducing power) and activities of the phenol metabolism-associated enzymes including phenylalanine ammonialyase (PAL), catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO) were evaluated. The results showed that treatment with 15 μl L(-1) H2S significantly inhibited the browning of fresh-cut lotus root slices (P<0.05), reduced significantly O2(-) production rate and H2O2 content, and enhanced antioxidant capacities (P<0.05). PPO and POD activities in the fresh-cut lotus root slices were also significantly inhibited by treatment with H2S (P<0.05). This study suggested that treatment with exogenous H2S could inhibit the browning of fresh-cut lotus root slices by enhancing antioxidant capacities to alleviate the oxidative damage. PMID:25660900

  2. Efficacy of post-storage irradiation to reduce Salmonella on sliced tomatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contamination of tomatoes with Salmonella is a recurring food safety concern. Irradiation is a nonthermal intervention that can inactivate pathogens on fresh produce. The best practices for implementing irradiation for fresh produce have yet to be determined. Roma tomatoes were sliced and inoculated...

  3. Measures of large-scale structure in the CfA redshift survey slices

    NASA Technical Reports Server (NTRS)

    De Lapparent, Valerie; Geller, Margaret J.; Huchra, John P.

    1991-01-01

    Variations of the counts-in-cells with cell size are used here to define two statistical measures of large-scale clustering in three 6 deg slices of the CfA redshift survey. A percolation criterion is used to estimate the filling factor which measures the fraction of the total volume in the survey occupied by the large-scale structures. For the full 18 deg slice of the CfA redshift survey, f is about 0.25 + or - 0.05. After removing groups with more than five members from two of the slices, variations of the counts in occupied cells with cell size have a power-law behavior with a slope beta about 2.2 on scales from 1-10/h Mpc. Application of both this statistic and the percolation analysis to simulations suggests that a network of two-dimensional structures is a better description of the geometry of the clustering in the CfA slices than a network of one-dimensional structures. Counts-in-cells are also used to estimate at 0.3 galaxy h-squared/Mpc the average galaxy surface density in sheets like the Great Wall.

  4. Measures of large-scale structure in the CfA redshift survey slices

    SciTech Connect

    De Lapparent, V.; Geller, M.J.; Huchra, J.P. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA )

    1991-03-01

    Variations of the counts-in-cells with cell size are used here to define two statistical measures of large-scale clustering in three 6 deg slices of the CfA redshift survey. A percolation criterion is used to estimate the filling factor which measures the fraction of the total volume in the survey occupied by the large-scale structures. For the full 18 deg slice of the CfA redshift survey, f is about 0.25 + or - 0.05. After removing groups with more than five members from two of the slices, variations of the counts in occupied cells with cell size have a power-law behavior with a slope beta about 2.2 on scales from 1-10/h Mpc. Application of both this statistic and the percolation analysis to simulations suggests that a network of two-dimensional structures is a better description of the geometry of the clustering in the CfA slices than a network of one-dimensional structures. Counts-in-cells are also used to estimate at 0.3 galaxy h-squared/Mpc the average galaxy surface density in sheets like the Great Wall. 46 refs.

  5. General Structure Design for Fast Image Processing Algorithms Based upon FPGA DSP Slice

    NASA Astrophysics Data System (ADS)

    Wasfy, Wael; Zheng, Hong

    Increasing the speed and accuracy for a fast image processing algorithms during computing the image intensity for low level 3x3 algorithms with different kernel but having the same parallel calculation method is our target to achieve in this paper. FPGA is one of the fastest embedded systems that can be used for implementing the fast image processing image algorithms by using DSP slice module inside the FPGA we aimed to get the advantage of the DSP slice as a faster, accurate, higher number of bits in calculations and different calculated equation maneuver capabilities. Using a higher number of bits during algorithm calculations will lead to a higher accuracy compared with using the same image algorithm calculations with less number of bits, also reducing FPGA resources as minimum as we can and according to algorithm calculations needs is a very important goal to achieve. So in the recommended design we used as minimum DSP slice as we can and as a benefit of using DSP slice is higher calculations accuracy as the DSP capabilities of having 48 bit accuracy in addition and 18 x 18 bit accuracy in multiplication. For proofing the design, Gaussian filter and Sobelx edge detector image processing algorithms have been chosen to be implemented. Also we made a comparison with another design for proofing the improvements of the accuracy and speed of calculations, the other design as will be mentioned later on this paper is using maximum 12 bit accuracy in adding or multiplying calculations.

  6. Effect of UV-B light and genotype on antioxidant enhancement of carrot slices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut processing (such as slicing) has been shown to enhance the nutrient content of carrots by stimulating the synthesis of secondary metabolites, including phenolic compounds. Ultraviolet-B (UV-B) light exposure in conjunction with wounding further promoted the formation of soluble phenolic co...

  7. Astronauts Conrad and Cooper slice cake on U.S.S. Lake Champlain

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Astronauts Charles Conrad Jr. (left) and L. Gordon Cooper Jr. prepate to slice into the huge cake prepared for them by the cooks onboard the aircraft carrier U.S.S. Lake Champlain. They are using ornamental Navy swords for knives.

  8. In Vitro Manganese Exposure Disrupts MAPK Signaling Pathways in Striatal and Hippocampal Slices from Immature Rats

    PubMed Central

    Peres, Tanara Vieira; Pedro, Daniela Zótico; de Cordova, Fabiano Mendes; Lopes, Mark William; Gonçalves, Filipe Marques; Mendes-de-Aguiar, Cláudia Beatriz Nedel; Walz, Roger; Farina, Marcelo; Aschner, Michael; Leal, Rodrigo Bainy

    2013-01-01

    The molecular mechanisms mediating manganese (Mn)-induced neurotoxicity, particularly in the immature central nervous system, have yet to be completely understood. In this study, we investigated whether mitogen-activated protein kinases (MAPKs) and tyrosine hydroxylase (TH) could represent potential targets of Mn in striatal and hippocampal slices obtained from immature rats (14 days old). The aim of this study was to evaluate if the MAPK pathways are modulated after subtoxic Mn exposure, which do not significantly affect cell viability. The concentrations of manganese chloride (MnCl2; 10–1,000 μM) caused no change in cell viability in slices exposed for 3 or 6 hours. However, Mn exposure significantly increased extracellular signal-regulated kinase (ERK) 1/2, as well as c-Jun N-terminal kinase (JNK) 1/2/3 phosphorylation at both 3 and 6 hours incubations, in both brain structures. Furthermore, Mn exposure did not change the total content or phosphorylation of TH at the serine 40 site in striatal slices. Thus, Mn at concentrations that do not disrupt cell viability causes activation of MAPKs (ERK1/2 and JNK1/2/3) in immature hippocampal and striatal slices. These findings suggest that altered intracellular MAPKs signaling pathways may represent an early event concerning the effects of Mn in the immature brain. PMID:24324973

  9. Chronic ethanol inhibits receptor-stimulated phosphoinositide hydrolysis in rat liver slices

    SciTech Connect

    Gonzales, R.A.; Crews, F.T. )

    1991-03-01

    The effects of chronic ethanol feeding on norepinephrine (NE)- and arginine-vasopressin (AVP)-stimulated phosphoinositide (PI) hydrolysis in rat liver slices was determined. The maximum NE-stimulated PI response was significantly reduced by 40% in liver slices from 8-month-old rats which had been treated for 5 months with a liquid diet containing ethanol compared to pair-fed controls. The maximum AVP-stimulated PI response was decreased by 39% in liver slices from the ethanol-fed rats compared to control. EC50 values for NE- and AVP-stimulated PI hydrolysis in liver slices were not affected by the chronic ethanol treatment. Similar reductions in the maximal NE- and AVP-stimulated PI hydrolysis (28% and 27%, respectively) were found in 22-month-old rats which had been maintained on an ethanol containing diet for 5 months compared to pair-fed controls. The binding of (3H)prazosin and (3H)AVP to liver plasma membranes from 8-month-old ethanol-fed rats was not significantly different from binding to liver membranes from sucrose-fed controls. Our data suggest that chronic ethanol ingestion may lead to a reduction in PI-linked signal transduction in liver.

  10. 3D Data Mapping and Real-Time Experiment Control and Visualization in Brain Slices.

    PubMed

    Navarro, Marco A; Hibbard, Jaime V K; Miller, Michael E; Nivin, Tyler W; Milescu, Lorin S

    2015-10-20

    Here, we propose two basic concepts that can streamline electrophysiology and imaging experiments in brain slices and enhance data collection and analysis. The first idea is to interface the experiment with a software environment that provides a 3D scene viewer in which the experimental rig, the brain slice, and the recorded data are represented to scale. Within the 3D scene viewer, the user can visualize a live image of the sample and 3D renderings of the recording electrodes with real-time position feedback. Furthermore, the user can control the instruments and visualize their status in real time. The second idea is to integrate multiple types of experimental data into a spatial and temporal map of the brain slice. These data may include low-magnification maps of the entire brain slice, for spatial context, or any other type of high-resolution structural and functional image, together with time-resolved electrical and optical signals. The entire data collection can be visualized within the 3D scene viewer. These concepts can be applied to any other type of experiment in which high-resolution data are recorded within a larger sample at different spatial and temporal coordinates. PMID:26488641

  11. Drying characteristics and modeling of yam slices under different relative humidity conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The drying characteristics of yam slices under different 23 constant relative humidity (RH) and step-down RH levels were studied. A mass transfer model was developed based on Bi-Di correlations containing a drying coefficient and a lag factor to describe the drying process. It was validated using ex...

  12. Breast mass detection using slice conspicuity in 3D reconstructed digital breast volumes

    NASA Astrophysics Data System (ADS)

    Kim, Seong Tae; Kim, Dae Hoe; Ro, Yong Man

    2014-09-01

    In digital breast tomosynthesis, the three dimensional (3D) reconstructed volumes only provide quasi-3D structure information with limited resolution along the depth direction due to insufficient sampling in depth direction and the limited angular range. The limitation could seriously hamper the conventional 3D image analysis techniques for detecting masses because the limited number of projection views causes blurring in the out-of-focus planes. In this paper, we propose a novel mass detection approach using slice conspicuity in the 3D reconstructed digital breast volumes to overcome the above limitation. First, to overcome the limited resolution along the depth direction, we detect regions of interest (ROIs) on each reconstructed slice and separately utilize the depth directional information to combine the ROIs effectively. Furthermore, we measure the blurriness of each slice for resolving the degradation of performance caused by the blur in the out-of-focus plane. Finally, mass features are extracted from the selected in focus slices and analyzed by a support vector machine classifier to reduce the false positives. Comparative experiments have been conducted on a clinical data set. Experimental results demonstrate that the proposed approach outperforms the conventional 3D approach by achieving a high sensitivity with a small number of false positives.

  13. The Use of Herpes Simplex Virus in Ex Vivo Slice Culture

    PubMed Central

    Friedman, Allyson K.

    2015-01-01

    Herpes simplex virus (HSV) can be used for a wide range of genetic manipulation in ex vivo slices of central nervous system tissue from both young and adult rodents. The fast expression of the HSV viral mediated gene transfer, which can be engineered to produce cell-type specificity, can be utilized in slice cultures for a variety of purposes over a 1-4 day period with spatial and temporal specificity. This protocol exploits the rapid expression of HSV viral vectors by utilizing slice culture for electrophysiological recordings, avoiding the need to do intra-cranial viral injections. Brain slice cultures maintain many aspects of in vivo biology, including functional local synaptic circuitry with preserved brain architecture, while allowing good experimental access and precise control of the extracellular environment, making them ideal platforms for quick access to evaluate expression effects of HSV viral mediated gene transfer on the molecular and cellular properties of specific neurons. This protocol provides an easy way to study neuronal function following expression of these HSV viruses. PMID:26131662

  14. EFFECT OF 1-METHYLCYCLOPROPENE ON THE QUALITY OF FRESH-CUT APPLE SLICES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this project was to treat fresh-cut apple slices with the ethylene-action inhibitor, 1-methylcyclopropene (1-MCP), in order to retard ethylene-induced deterioration and senescence, and prolong the shelf life of such products. Intact Braeburn and Pacific Rose apples were treated, at...

  15. Electrophysiology of Hypothalamic Magnocellular Neurons In vitro: A Rhythmic Drive in Organotypic Cultures and Acute Slices

    PubMed Central

    Israel, Jean-Marc; Oliet, Stéphane H.; Ciofi, Philippe

    2016-01-01

    Hypothalamic neurohormones are released in a pulsatile manner. The mechanisms of this pulsatility remain poorly understood and several hypotheses are available, depending upon the neuroendocrine system considered. Among these systems, hypothalamo-neurohypophyseal magnocellular neurons have been early-considered models, as they typically display an electrical activity consisting of bursts of action potentials that is optimal for the release of boluses of the neurohormones oxytocin and vasopressin. The cellular mechanisms underlying this bursting behavior have been studied in vitro, using either acute slices of the adult hypothalamus, or organotypic cultures of neonatal hypothalamic tissue. We have recently proposed, from experiments in organotypic cultures, that specific central pattern generator networks, upstream of magnocellular neurons, determine their bursting activity. Here, we have tested whether a similar hypothesis can be derived from in vitro experiments in acute slices of the adult hypothalamus. To this aim we have screened our electrophysiological recordings of the magnocellular neurons, previously obtained from acute slices, with an analysis of autocorrelation of action potentials to detect a rhythmic drive as we recently did for organotypic cultures. This confirmed that the bursting behavior of magnocellular neurons is governed by central pattern generator networks whose rhythmic drive, and thus probably integrity, is however less satisfactorily preserved in the acute slices from adult brains. PMID:27065780

  16. Analysis, design and performance evaluation of optical fiber spectrum-sliced WDM systems

    NASA Astrophysics Data System (ADS)

    Arya, Vivek

    This dissertation investigates the design and performance issues of a recently demonstrated technique, termed as spectrum-slicing, for implementing wavelength-division- multiplexing (WDM) in optical fiber systems. Conventional WDM systems employ laser diodes operating at discrete wavelengths as carriers for the different data channels that are to be multiplexed. Spectrum-slicing provides an attractive low-cost alternative to the use of multiple coherent lasers for such WDM applications by utilizing spectral slices of a broadband noise source for the different data channels. The principal broadband noise source considered is the amplified spontaneous emission (ASE) noise from an optical amplifier. Each slice of the spectrum is actually a burst of noise that is modulated individually for a high capacity WDM system. The stochastic nature of the broadband source gives rise to excess intensity noise which results in a power penalty at the receiver. One way to minimize this penalty, as proposed and analyzed for the first time in this work, is to use an optical preamplifier receiver. It is shown that when an optical preamplifier receiver is used, there exists an optimum filter bandwidth which optimizes the detection sensitivity (minimizes the average number of photons/bit) for a given error probability. Moreover the evaluated detection sensitivity represents an order of magnitude (>10 dB) improvement over conventional PIN receiver-based detection techniques for such spectrum-sliced communication systems. The optimum is a consequence of signal energy fluctuations dominating at low values of the signal time bandwidth product (m), and the preamplifier ASE noise dominating at high values of m. Operation at the optimum bandwidth renders the channel error probability to be a strong function of the optical bandwidth, thus providing motivation for the use of forward error correction coding (FEC). System capacity (for BER = 10-12) is shown to be 23 Gb/s without coding, and 75 Gb

  17. Bioactive alginate coatings to control Listeria monocytogenes on cold-smoked salmon slices and fillets.

    PubMed

    Neetoo, Hudaa; Ye, Mu; Chen, Haiqiang

    2010-01-01

    The relatively high incidence of Listeria monocytogenes in cold smoked salmon (CSS) is of concern as CSS is a ready-to-eat product. No post-processing measures are currently available to control this pathogen in CSS. The objective of this study was to develop an effective antimicrobial edible coating containing organic salts to control the growth of L. monocytogenes in CSS slices and fillets. An in-house made formulation consisting of sodium lactate (SL, 0-2.4%) and sodium diacetate (SD, 0-0.25%) as well as 2.5% OptiForm (a commercial formulation of SL and SD) were incorporated into five edible coatings: alginate, kappa-carrageenan, pectin, gelatin or starch. The coatings were applied onto the surface of CSS slices inoculated with L. monocytogenes to an inoculum level of 500 CFU/cm(2) ( approximately 3 log CFU/g) and stored at room temperature (22 degrees C) for 6 days. Alginate coating was found to be the most effective carrier for the various antimicrobial treatments in inhibiting the growth of L. monocytogenes. In the second phase of the study, CSS slices and fillets inoculated with the pathogen at a level of 500 CFU/cm(2) were coated with alginate incorporating the in-house made and the commercial (OptiForm) SL/SD based formulations and stored for 30 days at 4 degrees C. When cold-smoked salmon slices and fillets were stored at 4 degrees C, alginate coatings supplemented with 2.4%SL/0.25%SD and the commercial product OptiForm significantly delayed the growth of L. monocytogenes during the 30-day storage with final counts reaching 4.1 and 3.3 log CFU/g (slices) and 4.4 and 3.8 log CFU/g (fillets), respectively, while the counts in their untreated counterparts were significantly higher (P<0.05) reaching 7.3 and 6.8 log CFU/g for slices and fillets, respectively. Therefore, this study demonstrates the effectiveness of using an alginate-based coating containing lactate and diacetate to control the growth of L. monocytogenes to enhance the microbiological safety of

  18. Amputee Socks: Thickness of Multiple Socks

    PubMed Central

    Cagle, John C; Yu, Alan J; Ciol, Marcia A; Sanders, JE

    2015-01-01

    Background and Aim It is unclear how total sock ply and thickness are related when more than one sock is worn. The objectives were to determine if the thickness of one multi-ply amputee sock of ply P was the same as the thickness of a stack of reduced-ply socks of total ply P; and if the thickness of N single socks stacked one on top of the other was equal to the sum (1 to N) of the single sock thicknesses. Technique Using a custom instrument, compressive stresses were applied while sock thickness was measured. Discussion The thickness of one multi-ply sock of ply P was typically less than the thickness of a stack of reduced-ply socks of total ply P. The thickness of N single socks stacked one on top of the other was approximately equal to the sum (1 to N) of the single sock thicknesses. Clinical Relevance Our findings suggest three 1-ply socks to be 20% greater in thickness than one 3-ply sock, and one 3-ply + two 1-ply socks to be 30% greater in thickness than one 5-ply sock. PMID:24240023

  19. Influence of light curing unit and ceramic thickness on temperature rise during resin cement photo-activation.

    PubMed

    Guiraldo, Ricardo Danil; Consani, Simonides; Mastrofrancisco, Sarina; Consani, Rafael Leonardo Xediek; Sinhoreti, Mario Alexandre Coelho; Correr-Sobrinho, Lourenço

    2008-11-01

    The aim of this study was to determine the effect of different ceramic thickness on heat generation during resin cement photo-activation by QTH (quartz-tungsten-halogen), LED (light emitting diode), and PAC (plasma arc-curing) LCUs (light curing units). The resin cement used was Rely X ARC (3M-ESPE), and the ceramic was IPS Empress Esthetic (Ivoclar-Vivadent), of which 0.7-, 1.4- and 2.0-mm thick disks, 0.8 mm in diameter were made. Temperature increase was recorded with a type-K thermocouple connected to a digital thermometer (Iopetherm 46). An acrylic resin base was built to guide the thermocouple and support the 1.0-mm thick dentin disk. A 0.1-mm thick black adhesive paper matrix with a perforation 6 mm in diameter was placed on the dentin to contain the resin cement and support the ceramic disks of different thicknesses. Three LCUs were used: QTH, LED and PAC. Nine groups were formed (n=10) according to the interaction: 3 ceramic thicknesses, 1 resin cement and 3 photo-activation methods. Temperature increase data were submitted to Tukey's test (5%). For all ceramic thicknesses, a statistically significant difference in temperature increase was observed among the LCUs, with the highest mean value for the QTH LCU (p<0.05). For all the LCUs, a thickness of 0.7 mm produced the highest temperatures (1.4 and 2.0mm, p<0.05). There was no difference in temperature values between the latter two thicknesses (p>0.05). The interaction of higher energy density with smaller ceramic thickness showed higher temperature increase values. PMID:19420877

  20. Evaluation of mandibular cortical bone thickness for placement of temporary anchorage devices (TADs)

    PubMed Central

    Kim, Jung-Hoon

    2012-01-01

    Objective In this study, we measured the cortical bone thickness in the mandibular buccal and lingual areas using computed tomography in order to evaluate the suitability of these areas for application of temporary anchorage devices (TADs) and to suggest a clinical guide for TADs. Methods The buccal and lingual cortical bone thickness was measured in 15 men and 15 women. Bone thickness was measured 4 mm apical to the interdental cementoenamel junction between the mandibular canine and the 2nd molar using the transaxial slices in computed tomography images. Results The cortical bone in the mandibular buccal and lingual areas was thicker in men than in women. In men, the mandibular lingual cortical bone was thicker than the buccal cortical bone, except between the 1st and 2nd molars on both sides. In women, the mandibular lingual cortical bone was thicker in all regions when compared to the buccal cortical bone. The mandibular buccal cortical bone thickness increased from the canine to the molars. The mandibular lingual cortical bone was thickest between the 1st and 2nd premolars, followed by the areas between the canine and 1st premolar, between the 2nd premolar and 1st molar, and between the 1st molar and 2nd molar. Conclusions There is sufficient cortical bone for TAD applications in the mandibular buccal and lingual areas. This provides the basis and guidelines for the clinical use of TADs in the mandibular buccal and lingual areas. PMID:23112941

  1. Preparation of postsynaptic density fraction from hippocampal slices and proteomic analysis

    SciTech Connect

    Dosemeci, Ayse . E-mail: dosemeca@mail.nih.gov; Tao-Cheng, J.-H.; Vinade, Lucia; Jaffe, Howard

    2006-01-13

    Hippocampal slices offer an excellent experimental system for the study of activity-induced changes in the postsynaptic density (PSD). While studies have documented electrophysiological and structural changes at synapses in response to precise manipulations of hippocampal slices, parallel biochemical and proteomic analyses were hampered by the lack of subcellular fractionation techniques applicable to starting tissue about three orders of magnitude smaller than that used in conventional protocols. Here, we describe a simple and convenient method for the preparation of PSD fractions from hippocampal slices and the identification of its components by proteomic techniques. The 'micro PSD fraction' obtained following two consecutive extractions of a synaptosomal fraction with Triton X-100 shows a significant enrichment in the marker protein PSD-95. Thin section electron microscopy shows PSDs similar to those observed in situ. However, other particulate material, especially myelin, and membrane vesicles are also present. The composition of the PSD fraction from hippocampal slices was analyzed by 2D LC/MS/MS. The proteomic approach which utilizes as little as 10 {mu}g total protein allowed the identification of >100 proteins. Many of the proteins detected in the fraction are the same as those identified in conventional PSD preparations including specialized PSD-scaffolding proteins, signaling molecules, cytoskeletal elements as well as certain contaminants. The results show the feasibility of the preparation of a PSD fraction from hippocampal slices of reasonable purity and of sufficient yield for proteomic analyses. In addition, we show that further purification of PSDs is possible using magnetic beads coated with a PSD-95 antibody.

  2. Ruminant organotypic brain-slice cultures as a model for the investigation of CNS listeriosis

    PubMed Central

    Guldimann, Claudia; Lejeune, Beatrice; Hofer, Sandra; Leib, Stephen L; Frey, Joachim; Zurbriggen, Andreas; Seuberlich, Torsten; Oevermann, Anna

    2012-01-01

    Central nervous system (CNS) infections in ruminant livestock, such as listeriosis, are of major concern for veterinary and public health. To date, no host-specific in vitro models for ruminant CNS infections are available. Here, we established and evaluated the suitability of organotypic brain-slices of ruminant origin as in vitro model to study mechanisms of Listeria monocytogenes CNS infection. Ruminants are frequently affected by fatal listeric rhombencephalitis that closely resembles the same condition occurring in humans. Better insight into host–pathogen interactions in ruminants is therefore of interest, not only from a veterinary but also from a public health perspective. Brains were obtained at the slaughterhouse, and hippocampal and cerebellar brain-slices were cultured up to 49 days. Viability as well as the composition of cell populations was assessed weekly. Viable neurons, astrocytes, microglia and oligodendrocytes were observed up to 49 days in vitro. Slice cultures were infected with L. monocytogenes, and infection kinetics were monitored. Infected brain cells were identified by double immunofluorescence, and results were compared to natural cases of listeric rhombencephalitis. Similar to the natural infection, infected brain-slices showed focal replication of L. monocytogenes and bacteria were predominantly observed in microglia, but also in astrocytes, and associated with axons. These results demonstrate that organotypic brain-slice cultures of bovine origin survive for extended periods and can be infected easily with L. monocytogenes. Therefore, they are a suitable model to study aspects of host–pathogen interaction in listeric encephalitis and potentially in other neuroinfectious diseases. PMID:22804762

  3. Ruminant organotypic brain-slice cultures as a model for the investigation of CNS listeriosis.

    PubMed

    Guldimann, Claudia; Lejeune, Beatrice; Hofer, Sandra; Leib, Stephen L; Frey, Joachim; Zurbriggen, Andreas; Seuberlich, Torsten; Oevermann, Anna

    2012-08-01

    Central nervous system (CNS) infections in ruminant livestock, such as listeriosis, are of major concern for veterinary and public health. To date, no host-specific in vitro models for ruminant CNS infections are available. Here, we established and evaluated the suitability of organotypic brain-slices of ruminant origin as in vitro model to study mechanisms of Listeria monocytogenes CNS infection. Ruminants are frequently affected by fatal listeric rhombencephalitis that closely resembles the same condition occurring in humans. Better insight into host-pathogen interactions in ruminants is therefore of interest, not only from a veterinary but also from a public health perspective. Brains were obtained at the slaughterhouse, and hippocampal and cerebellar brain-slices were cultured up to 49 days. Viability as well as the composition of cell populations was assessed weekly. Viable neurons, astrocytes, microglia and oligodendrocytes were observed up to 49 days in vitro. Slice cultures were infected with L. monocytogenes, and infection kinetics were monitored. Infected brain cells were identified by double immunofluorescence, and results were compared to natural cases of listeric rhombencephalitis. Similar to the natural infection, infected brain-slices showed focal replication of L. monocytogenes and bacteria were predominantly observed in microglia, but also in astrocytes, and associated with axons. These results demonstrate that organotypic brain-slice cultures of bovine origin survive for extended periods and can be infected easily with L. monocytogenes. Therefore, they are a suitable model to study aspects of host-pathogen interaction in listeric encephalitis and potentially in other neuroinfectious diseases. PMID:22804762

  4. Detecting personal familiarity depends on static frames in "thin slices" of behavior.

    PubMed

    Saville, Alyson; Balas, Benjamin

    2014-12-01

    Brief glimpses of nonverbal behavior (or "thin slices") offer ample visual information to make reliable judgments about individuals. Previous work has largely focused on the personality characteristics and traits of individuals; however, the nature of dyadic relationships (strangers, lovers, or friends) can also be determined (Ambady & Gray, Journal of Personality and Social Psychology, 83, 947-961 2002). Judgments from thin slices are known to be accurate, but the motion features supporting accurate performance are unknown. We explored whether personal familiarity was detectable within the context of "thin slices" of genuine interaction, as well as the invariant properties of thin-slice recognition. In two experiments, participants sequentially viewed two 6-s silent videos on each trial of an individual interacting with an unfamiliar partner; the other depicted the same person interacting with a personally familiar partner. All sequences were cropped so that only the target individual was visible. In Experiment 1, participants viewed either the original sequences, reversed sequences, a static-image "slideshow" of the sequence, or a static-image slideshow with blank frames separating the images. In Experiment 2, all participants viewed the original sequences and clips played at either double speed or half speed. Participants' performance was above chance in the forward and reverse conditions, but was significantly better in both the static-image slideshow conditions. When task speed was manipulated, we found a larger performance cost for fast than for slow videos. Detecting personal familiarity via spontaneous natural gestures depends on information in static images more than on face or body movement. Although static images are typically less important for recognizing nonverbal behavior, we argue they may be valuable for making familiarity judgments from thin slices. PMID:24683099

  5. Reconstructing liver shape and position from MR image slices using an active shape model

    NASA Astrophysics Data System (ADS)

    Fenchel, Matthias; Thesen, Stefan; Schilling, Andreas

    2008-03-01

    We present an algorithm for fully automatic reconstruction of 3D position, orientation and shape of the human liver from a sparsely covering set of n 2D MR slice images. Reconstructing the shape of an organ from slice images can be used for scan planning, for surgical planning or other purposes where 3D anatomical knowledge has to be inferred from sparse slices. The algorithm is based on adapting an active shape model of the liver surface to a given set of slice images. The active shape model is created from a training set of liver segmentations from a group of volunteers. The training set is set up with semi-manual segmentations of T1-weighted volumetric MR images. Searching for the optimal shape model that best fits to the image data is done by maximizing a similarity measure based on local appearance at the surface. Two different algorithms for the active shape model search are proposed and compared: both algorithms seek to maximize the a-posteriori probability of the grey level appearance around the surface while constraining the surface to the space of valid shapes. The first algorithm works by using grey value profile statistics in normal direction. The second algorithm uses average and variance images to calculate the local surface appearance on the fly. Both algorithms are validated by fitting the active shape model to abdominal 2D slice images and comparing the shapes, which have been reconstructed, to the manual segmentations and to the results of active shape model searches from 3D image data. The results turn out to be promising and competitive to active shape model segmentations from 3D data.

  6. Crystal ion slicing of optical oxides and plasmon-enhanced optical applications

    NASA Astrophysics Data System (ADS)

    Roth, Ryan M.

    The past three decades have been witness to rapid growth in the microelectronics and optoelectronic industries. A principal reason for this growth is the emergence and development of new materials, concepts and techniques for integrated device technologies that allow devices with complex functionalities to be miniaturized and combined on the chip-scale. In particular, technologies that allow for the fabrication of heterogeneous thin film structures have been especially valuable. One such technology, Crystal Ion Slicing (CIS), was developed at Columbia University and has been refined in recent years. CIS uses high-energy ion bombardment to exfoliate or 'slice' a thin, high-quality layer from the top surface of a parent optical crystal. Because the fabricated films produced by this technique share the physical, optical and electrical properties of the parent crystal, they are often superior to films achievable through other methods. In addition to thin oxide-film technology advances, there has been in recent years considerable interest in the emerging field of plasmonics. Plasmonics refers to the collection of integrated optical devices that utilize surface plasmon-polaritons generated at the interface of a metal and a dielectric, and the theories of their operation. The plasmons used in these devices may either be propagating or 'localized' plasmon resonances, are characterized by the exceptionally large electric field they carry, and in many cases demonstrate non-intuitive and startling physical behavior. Plasmonic device geometries have been intently studied because they possess great potential for nanoscale optical components, including devices whose principal feature sizes are smaller than the wavelength of light that they manipulate. This would in turn allow for hereto-unachievable levels of miniaturization and integration, reducing operational power and unit costs while increasing functionality. Unfortunately, the physics that govern plasmon interactions with

  7. Microstrip dipole antennas on electrically thick substrates

    NASA Astrophysics Data System (ADS)

    Jackson, D. R.; Alexopoulos, N. G.

    1985-10-01

    Printed circuit antennas are attractive radiation sources both at microwave and millimeter wave frequencies. However, for millimeter wave applications where the substrate is likely to be electrically thick, it is important to understand the basic effects of a thick substrate on radiation characteristics. In particular, it is concluded here that dipole radiation properties become sensitive to loss as the substrate becomes thick. Furthermore, the efficiency of dipoles on thick substrates tends to be low, especially as the dielectric constant of the substrate increases. A method of improving both the efficiency and gain can be used for thick substrates, however, which uses a superstrate layer on top of the antenna.

  8. Intelligent processing for thick composites

    NASA Astrophysics Data System (ADS)

    Shin, Daniel Dong-Ok

    2000-10-01

    Manufacturing thick composite parts are associated with adverse curing conditions such as large in-plane temperature gradient and exotherms. The condition is further aggravated because the manufacturer's cycle and the existing cure control systems do not adequately counter such affects. In response, the forecast-based thermal control system is developed to have better cure control for thick composites. Accurate cure kinetic model is crucial for correctly identifying the amount of heat generated for composite process simulation. A new technique for identifying cure parameters for Hercules AS4/3502 prepreg is presented by normalizing the DSC data. The cure kinetics is based on an autocatalytic model for the proposed method, which uses dynamic and isothermal DSC data to determine its parameters. Existing models are also used to determine kinetic parameters but rendered inadequate because of the material's temperature dependent final degree of cure. The model predictions determined from the new technique showed good agreement to both isothermal and dynamic DSC data. The final degree of cure was also in good agreement with experimental data. A realistic cure simulation model including bleeder ply analysis and compaction is validated with Hercules AS4/3501-6 based laminates. The nonsymmetrical temperature distribution resulting from the presence of bleeder plies agreed well to the model prediction. Some of the discrepancies in the predicted compaction behavior were attributed to inaccurate viscosity and permeability models. The temperature prediction was quite good for the 3cm laminate. The validated process simulation model along with cure kinetics model for AS4/3502 prepreg were integrated into the thermal control system. The 3cm Hercules AS4/3501-6 and AS4/3502 laminate were fabricated. The resulting cure cycles satisfied all imposed requirements by minimizing exotherms and temperature gradient. Although the duration of the cure cycles increased, such phenomena was

  9. The effect of collagen-chitosan porous scaffold thickness on dermal regeneration in a one-stage grafting procedure.

    PubMed

    Haifei, Shi; Xingang, Wang; Shoucheng, Wu; Zhengwei, Mao; Chuangang, You; Chunmao, Han

    2014-01-01

    Dermal substitutes are used as dermal regeneration templates to reduce scar formation and improve wound healing. Unlike autografts, dermal substitutes lack normal vascular networks. The increased distance required for diffusion of oxygen and nutrients to the autograft following interpositioning of the substitute dramatically affects graft survival. To evaluate the effect of collagen-chitosan scaffold thickness on dermal regeneration, single-layer collagen-chitosan porous scaffolds of 0.5-, 1- and 2-mm thicknesses were fabricated and used to treat full-thickness wounds in a one-stage grafting procedure in a rat model. Skin-graft viability, wound contraction, histological changes, and wound tensile strength were evaluated. The results indicated that the distance for the diffusion of oxygen and nutrients to the autograft in the 2-mm-thick scaffold provided less support for graft take, which resulted in graft necrosis, extensive inflammatory reaction, marked foreign-body reaction (FBR), rapid scaffold degradation, and abnormal collagen deposition and remodeling. In contrast, the thinner scaffolds, especially of that 0.5-mm thickness, promoted earlier angiogenesis, ensuring skin-graft viability with a mild FBR, and ordered fibroblast infiltration and better collagen remodeling. It can be concluded that collagen-chitosan porous scaffolds with a thickness of <1mm are more suitable for dermal regeneration and can be used as dermal templates for treatment of dermal defects using a one-stage grafting procedure. PMID:24076783

  10. Dynamic three-dimensional echocardiographic imaging of congenital heart defects in infants and children by computer-controlled tomographic parallel slicing using a single integrated ultrasound instrument.

    PubMed

    Fulton, D R; Marx, G R; Pandian, N G; Romero, B A; Mumm, B; Krauss, M; Wollschläger, H; Ludomirsky, A; Cao, Q L

    1994-03-01

    Three-dimensional cardiac reconstruction generated from transesophageal interrogation can be performed using an integrated unit that captures, processes, and postprocesses tomographic parallel slices of the heart. This probe was used for infants and young children in the transthoracic position to evaluate the feasibility of producing three-dimensional cardiac images with capability for real-time dynamic display. Twenty-two infants and children (range 1 day-3.5 years) underwent image acquisition using a 16 mm 5 MHz 64 element probe placed over the precordium. Two infants were also imaged from the subcostal position. Data was obtained and stored over a single cardiac cycle after acceptable cardiac and respiratory gating intervals were met. The transducer was advanced in 0.5-1 mm increments over the cardiac structures using identical acquisition criteria. The images were reconstructed from the stored digital cubic format and could be oriented in any desired plane. In 9 of the 22 infants the images obtained were of optimal quality. The images obtained displayed normal cardiac structures emphasizing depth relationships as well as visualization of planes not generally demonstrated by two-dimensional imaging. Several lesions were also depicted in a unique fashion using this technique. Though the method employed was limited by movement artifact and reconstruction time, the quality of the three-dimensional display was excellent and enhanced by real-time demonstration. The transthoracic approach was successful in capturing sufficient data to create three-dimensional images, which may have further application in more accurate diagnosis of complex cardiac abnormalities and generation of planes of view which could duplicate surgical visualization of a lesion. Further assessment of the technique in infants with congenital heart disease is warranted. PMID:10146717

  11. Pavement thickness evaluation using ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Harris, Dwayne Arthur

    Accurate knowledge of pavement thickness is important information to have both at a network and project level. This information aids in pavement management and design. Much of the time this information is missing, out of date, or unknown for highway sections. Current technologies for determining pavement thickness are core drilling, falling weight deflectometer (FWD), and ground penetrating radar (GPR). Core drilling provides very accurate pin point pavement thickness information; however, it is also time consuming, labor intensive, intrusive to traffic, destructive, and limited in coverage. FWD provides nondestructive estimates of both a surface thickness and total pavement structure thickness, including pavement, base and sub-base. On the other hand, FWD is intrusive to traffic and affected by the limitations and assumptions the method used to estimate thickness. GPR provides pavement surface course thickness estimates with excellent data coverage at highway speed. Yet, disadvantages include the pavement thickness estimation being affected by the electrical properties of the pavement, limitations of the system utilized, and heavy post processing of the data. Nevertheless, GPR has been successfully utilized by a number of departments of transportation (DOTs) for pavement thickness evaluation. This research presents the GPR thickness evaluation methods, develops GPRPAVZ the software used to implement the methodologies, and addresses the quality of GPR pavement thickness evaluation.

  12. Relation between visceral fat and carotid intimal media thickness in Mexican postmenopausal women: a preliminary report

    PubMed Central

    Azpilcueta, Yessica Mireya Moreno; Ortiz, Sergio Rosales

    2016-01-01

    Aim of the study To investigate the relationship between visceral fat and carotid IMT (intima media thickness) in Mexican postmenopausal women. Material and methods In 71 postmenopausal women divided in two groups: group 1, IMT > 1 mm and group 2, IMT ≤ 1 mm, blood pressure, body mass index (BMI), waist hip ratio (WHR), visceral and subcutaneous fats and carotid IMT were analyzed. Descriptive statistics were used and the comparison among those with abnormal and normal IMT was carried out using Mann-Whitney U test; also Spearman's correlation analysis was done. Results When comparing group 1 (n = 9, 12.7%) with group 2 (n = 62, 87.3%), it was found that the subcutaneous fat, visceral fat and systolic blood pressure were significantly greater in group 1 (p < 0.018, p < 0.001 and p < 0.006, respectively), and also in this group there was a correlation between BMI and subcutaneous fat (ρ = 0.686, p < 0.041) and between visceral fat and the systolic blood pressure (ρ = 0.712, p < 0.031). In group 2, there was a correlation between IMT and diastolic blood pressure (ρ = 0.251, p < 0.049). Conclusion Subcutaneous and visceral fat have an unfavorable effect in the carotid IMT and in blood pressure. PMID:27582681

  13. Thickness effect on HVOF coatings

    SciTech Connect

    Thorpe, R.

    1994-12-31

    Hobart/Tafa`s JP-5000`s particle velocity has a unique effect on coatings. This paper discusses the effect of thickness on coating properties such as: integrity, bond strength, stresses and coating performance. Much has been said about the advantages of these coatings. The goal of this paper if to provide additional substantiation. Higher operating pressure gun with high particle velocity yields coating properties that allow them to be applied thicker than ever before. the properties of these thicker coatings are evaluated versus micro-integrity, porosity, bond strength, oxide content and performance. Other comparisons are considered. Stresses in those coatings are a key part of this evaluation. Due to the unique coating stresses, corrosion and stress-corrosion resistance properties are improved. Also, mechanical and thermal fatigue properties are enhanced. A few case histories will be examined as documentation of actual field history. The types of applications involved are high and low temperature particle erosion; impact and sliding wear; immersion and heat corrosion; dimensional restoration of superalloys.

  14. Antibrowning and antimicrobial properties of sodium acid sulfate in apple slices.

    PubMed

    Fan, Xuetong; Sokorai, Kimberly J B; Liao, Ching-Hsing; Cooke, Peter; Zhang, Howard Q

    2009-01-01

    There are few available compounds that can both control browning and enhance microbial safety of fresh-cut fruits. In the present study, the antibrowning ability of sodium acid sulfate (SAS) on "Granny Smith" apple slices was first investigated in terms of optimum concentration and treatment time. In a separate experiment, the apple slices were treated with water or 3% of SAS, calcium ascorbate, citric acid, or acidified calcium sulfate for 5 min. Total plate count, color, firmness, and tissue damage were assessed during a 21-d storage at 4 degrees C. Results showed that the efficacy of SAS in inhibiting browning of apple slices increased with increasing concentration. A minimum 3% of SAS was needed to achieve 14 d of shelf life. Firmness was not significantly affected by SAS at 3% or lower concentrations. Antibrowning potential of SAS was similar for all treatment times ranging from 2 to 10 min. However, SAS caused some skin discoloration of apple slices. When cut surface of apple slices were stained with a fluorescein diacetate solution, tissue damage could be observed under a microscope even though visual damage was not evident. Among the antibrowning agents tested, SAS was the most effective in inhibiting browning and microbial growth for the first 14 d. Total plate count of samples treated with 3% SAS was significantly lower than those treated with calcium ascorbate, a commonly used antibrowning agent. Our results suggested that it is possible to use SAS to control browning while inhibiting the growth of microorganisms on the apple slices if the skin damage can be minimized. Practical Application: Fresh-cut apples have emerged as one of the popular products in restaurants, schools, and food service establishments as more consumers demand fresh, convenient, and nutritious foods. Processing of fresh-cut apples induces mechanical damage to the fruit and exposes apple tissue to air, resulting in the development of undesirable tissue browning. The fresh

  15. SUEX process optimization for ultra-thick high-aspect ratio LIGA imaging

    NASA Astrophysics Data System (ADS)

    Johnson, Donald W.; Goettert, Jost; Singh, Varshni; Yemane, Dawit

    2011-04-01

    The focus of this paper is on the use of SUEX Thick Dry Film Sheet (TDFS) laminates which DJ DevCorp is developing as a thick resist material in optical and X-ray lithography. Preliminary thick dry film sheets up to 1mm thickness were successfully prepared and patterned at the CAMD X-ray beamlines and presented at HARMST 2007. Recently, new results have been published using SUEX resist sheets in UV lithography showing great market potential including plating molds for metal microparts, polymer MEMS, multilayer microfluidics structures, BioMEMS, medical devices, wafer level packaging processes, and displays. The SUEX TDFS are available in a range of thicknesses from 100μm to 1mm or more and are pre-cut into a number of standard wafer sizes. This new material is a modified epoxy formulation containing an antimony-free photo acid generator (PAG) prepared under a highly controlled solvent-less process which provides uniform coatings between two throw-away layers of protective polyester film. As part of our initial studies resist layers of 250, 500 and 1000μm were laminated onto regular silicon wafers using a hot roll laminator at a speed of 1ft/min at 75°C. The entire substrate preparation takes about 1 hour and with practice users can prepare up to 10 substrates in this time which are typically ready to use within 2 hours. In our efforts to develop a commercially viable product we have conducted experiments using standard equipment available at CAMD (Quintel UV aligner and CAMD XRLM 1 and 4 beamline). Initial X-ray exposure tests were done with a bottom dose ranging between 100 and 400 J/cm3 and a top/bottom dose ratio of less than 3 for sheets up to 2mm in thickness. Exposure time for typical conditions of the CAMD storage ring (ring current ranging between 100 and 160mA, beam lifetime of about 10hrs at 100mA ring current) is about 10-15min for a 4' wafer. After exposure the samples were immediately post exposure baked between 70°C and 110°C using a convection

  16. Influence of transient intraocular pressure elevation during laser in situ keratomileusis on rabbit retina thickness

    PubMed Central

    Zhao, Hai-Xia; Liu, Hui; Niu, Chun-Mei; Guan, Wen-Ying

    2015-01-01

    AIM To utilize tissue micro measurement to study the effect of transient high intraocular pressure (IOP) induced by different durations of suction during laser in situ keratomileusis (LASIK) on rabbit retina thickness. METHODS Sixty healthy New Zealand white rabbits were randomly divided into a control group, and 3 negative-pressure suction groups (20s group, 45s group, and 3min group) and each group was comprised of 15 rabbits (30 eyes); the latter 3 groups were the transient high IOP models. The retinal tissue around the papilledema was separated. Hematoxylin and eosin (HE) staining was carried out to generate slices for light microscopy. The changes in the retina thickness values of each layer were measured for all animals in each group at different postoperative recovery periods and compared with the values recorded for the animals in the control group. The thickness of the retinal tissue showed a normal distribution. The ANOVA was performed by using SPSS13.0 statistic software. RESULTS In the comparison between the 20s and 45s negative-pressure suction groups and the control group, no significant differences were observed, except at 14d. Significant difference was observed between the 3min negative-pressure suction group and the control group, and the retina thickness value of each layer reached a peak at 14d after repair. CONCLUSION Conventional negative suction during LASIK may not lead to significant changes in retinal tissue thickness; however, if the suction duration is increased to 3min, it will cause significant changes in retinal tissue thickness. PMID:26682153

  17. Videomicroscopy of methacholine-induced contraction of individual airways in precision-cut lung slices.

    PubMed

    Martin, C; Uhlig, S; Ullrich, V

    1996-12-01

    Contraction of airways of different size can be studied in viable lung slices by videomicroscopy. However, at present, application of this technique is limited by the heterogeneous responses obtained. We investigated the use of precision-cut lung slices to examine contraction of individual airways. Lung slices of 250 +/- 20 microns were prepared from Wistar rats and cultured in a roller incubator in serum-free minimum essential medium (MEM). Under these conditions, the slices were viable for at least 70 h, as indicated by leakage of lactate dehydrogenase into the supernatant, thymidine incorporation and ciliary beating. The slices were placed in a newly developed incubation chamber and mounted by a nylon thread that was fixed to a platinum wire. The whole chamber was positioned on a microscope stage, and contraction of single airways was followed under a microscope that was coupled to a CCD-camera. Reduction in airway area was taken as an index of bronchoconstriction and was determined by a computer program. Addition of methacholine resulted in a concentration-dependent (concentration producing half the maximal effect (EC50) = 0.64 +/- 0.08 (mean +/- SD) microM; n = 64) contraction of single airways. In the presence of hydrocortisone, the EC50 was about six times greater, i.e. 3.7 +/- 0.9 microM (n = 7), and the effect of the steroid was largely abolished by propanolol (EC50 = 1.1 +/- 0.1 microM; n = 7). Airways with an area smaller than 35,000 microns2 were nearly nine times more sensitive to methacholine (EC50 = 0.1 +/- 0.03 microM; n = 20) than larger ones (EC50 = 87 +/- 0.27 microM; n = 22). We conclude that cultured precision-cut lung slices are a useful model for routine study of contraction of individual airways of various sizes. The measurements were precise and reproducible and showed that smaller airways are more sensitive to methacholine than larger ones. PMID:8980957

  18. Cosmo-geo-anthropo-logical history and political and deep future events in climate and life evolution conveyed by a physical/virtual installation at a scale of 1 mm per 100 years across Denmark during the COP15 climate summit meeting.

    NASA Astrophysics Data System (ADS)

    Holm Jacobsen, Bo

    2010-05-01

    During the COP15 climate summit meeting a physical and virtual installation of time was performed at a linear scale of 1 mm per 100 years. The "track of time" was carefully anchored geographically so that highlights in time history coincided with landmarks of historical and cultural significance to both tourists and the local Danish population; with Big Bang at the site of early royal settlements from the Viking age (13.7 billion years ~ 137 km from now), Earth origin at Kronborg in Elsinore (4.6 bil. Years ~ 46 km), and fish go on land at The Little Mermaid (390 mil. Years ~ 3900 m). The venue of the COP15 meeting coincided with the position of severe global warming, driven by the steady solar constant increase, to be expected 600 million years into the future. Nested in this grand track of time were the Quaternary ice-ages (2.6 mil. years ~ 26 m), human origin as species (100,000 years ~ 1 m), human history (< 10,000 years ~ 100 mm), personal life and the scope of political consequences of voting action (100 years ~ 1 mm). This installation of time involved several media. Highlights in time history and future were installed as a kml-file so that the convenient user interface of Google Earth could be utilized to provide both overview of time and understanding of details and proportions events antropo-geo-cosmo-history. Each Google Earth marker-balloon gave short explanations and linked to "on location" video-narratives. A classical printed text-folder was prepared as a tour guide for those who wanted to actually walk the Phanerozoic (~5 km). Credit-card-shaped graphs of temperature, CO2 and sealevel development and scenarios were prepared to scale for the period 4000 BP to 1000 years into the future. Along the time line from "Fish on land" to the present 3900 chalk marks were placed on the street surface, one for every metre = time span of Man as a species so far. A "NowGate" marking the present was implemented physically as a door frame, where citizens could meet

  19. Isoproterenol effects evaluated in heart slices of human and rat in comparison to rat heart in vivo

    SciTech Connect

    Herrmann, Julia E.; Heale, Jason; Bieraugel, Mike; Ramos, Meg; Fisher, Robyn L.; Vickers, Alison E.M.

    2014-01-15

    Human response to isoproterenol induced cardiac injury was evaluated by gene and protein pathway changes in human heart slices, and compared to rat heart slices and rat heart in vivo. Isoproterenol (10 and 100 μM) altered human and rat heart slice markers of oxidative stress (ATP and GSH) at 24 h. In this in vivo rat study (0.5 mg/kg), serum troponin concentrations increased with lesion severity, minimal to mild necrosis at 24 and 48 h. In the rat and the human heart, isoproterenol altered pathways for apoptosis/necrosis, stress/energy, inflammation, and remodeling/fibrosis. The rat and human heart slices were in an apoptotic phase, while the in vivo rat heart exhibited necrosis histologically and further progression of tissue remodeling. In human heart slices genes for several heat shock 70 kD members were altered, indicative of stress to mitigate apoptosis. The stress response included alterations in energy utilization, fatty acid processing, and the up-regulation of inducible nitric oxide synthase, a marker of increased oxidative stress in both species. Inflammation markers linked with remodeling included IL-1α, Il-1β, IL-6 and TNFα in both species. Tissue remodeling changes in both species included increases in the TIMP proteins, inhibitors of matrix degradation, the gene/protein of IL-4 linked with cardiac fibrosis, and the gene Ccl7 a chemokine that induces collagen synthesis, and Reg3b a growth factor for cardiac repair. This study demonstrates that the initial human heart slice response to isoproterenol cardiac injury results in apoptosis, stress/energy status, inflammation and tissue remodeling at concentrations similar to that in rat heart slices. - Highlights: • Human response to isoproterenol induced cardiac injury evaluated in heart slices. • Isoproterenol altered apoptosis, energy, inflammation and remodeling pathways. • Human model verified by comparison to rat heart slices and rat heart in vivo. • Human and rat respond to isoproterenol

  20. Respiratory-gated segment reconstruction for radiation treatment planning using 256-slice CT-scanner during free breathing

    NASA Astrophysics Data System (ADS)

    Mori, Shinichiro; Endo, Masahiro; Kohno, Ryosuke; Minohara, Shinichi; Kohno, Kazutoshi; Asakura, Hiroshi; Fujiwara, Hideaki; Murase, Kenya

    2005-04-01

    The conventional respiratory-gated CT scan technique includes anatomic motion induced artifacts due to the low temporal resolution. They are a significant source of error in radiotherapy treatment planning for the thorax and upper abdomen. Temporal resolution and image quality are important factors to minimize planning target volume margin due to the respiratory motion. To achieve high temporal resolution and high signal-to-noise ratio, we developed a respiratory gated segment reconstruction algorithm and adapted it to Feldkamp-Davis-Kress algorithm (FDK) with a 256-detector row CT. The 256-detector row CT could scan approximately 100 mm in the cranio-caudal direction with 0.5 mm slice thickness in one rotation. Data acquisition for the RS-FDK relies on the assistance of the respiratory sensing system by a cine scan mode (table remains stationary). We evaluated RS-FDK in phantom study with the 256-detector row CT and compared it with full scan (FS-FDK) and HS-FDK results with regard to volume accuracy and image noise, and finally adapted the RS-FDK to an animal study. The RS-FDK gave a more accurate volume than the others and it had the same signal-to-noise ratio as the FS-FDK. In the animal study, the RS-FDK visualized the clearest edges of the liver and pulmonary vessels of all the algorithms. In conclusion, the RS-FDK algorithm has a capability of high temporal resolution and high signal-to-noise ratio. Therefore it will be useful when combined with new radiotherapy techniques including image guided radiation therapy (IGRT) and 4D radiation therapy.