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Sample records for 1-2 mm diameter

  1. 29 mm Diameter Test Target Design Report

    SciTech Connect

    Woloshun, Keith Albert; Dale, Gregory E.; Olivas, Eric Richard; Naranjo, Angela Carol; Romero, Frank Patrick

    2016-08-15

    The Northstar target for Mo99 production is made up of Mo100 disks in a stack separated by coolant gaps for helium flow. A number of targets have been tested at ANL for both production of Mo99 and for thermal-hydraulic performance. These have all been with a 12 mm diameter target, even while the production goals have increased the diameter to now 29 mm. A 29 mm diameter target has been designed that is consistent with the ANL beam capabilities and the capabilities of the helium circulation system currently in use at ANL. This target is designed for 500 μA at 35 MeV electrons. While the plant design calls for 42 MeV, the chosen design point is more favorable and higher power given the limits of the ANL accelerator. The intended beam spot size is 12 mm FWHM, but the thermal analysis presented herein conservatively assumed a 10 mm FWHM beam, which results in a 44% higher beam current density at beam center.

  2. A 24mm diameter fibre positioner for spectroscopic surveys

    NASA Astrophysics Data System (ADS)

    Hörler, Philipp; Kronig, Luzius; Kneib, Jean-Paul; Bleuler, Hannes; Bouri, Mohamed

    2016-07-01

    One of the big research topics in modern cosmology is the mystery of dark Energy. To unveil the secret, cosmologists want to measure precisely the evolution of large scale structures in the universe. One way of doing so is to measure the 3D location of a high number of galaxies. By measuring the redshift of a galaxy, it is possible to find its distance. In order to measure a high number of galaxies in a practical amount of time, we need to observe multiple objects in parallel. Instead of a spectrograph, thousands of optical fibres are placed in the focal plane of a telescope. They will transmit the light of many objects to a spectrograph. Each fibre has to be positioned to several μm precision in the focal plane of a telescope for each exposure. Each fibre is positioned by a 2-axis fibre positioner. In this paper such a fibre positioner with 24-mm diameter is presented. It is driven by two brushless DC motors in combination with a backlash free gearbox. The positioner has an optimal central fibre path and improved angular alignment. The fibre runs through the centre of the positioner and is only bent at the top to reach its target position. In this way, the flexion and torsion of the fibre are minimal. In addition to the high positioning accuracy, the design is optimized to allow a minimal tilt error of the fibre. This is demonstrated using a novel optical tilt measurement system.

  3. Growth of 450 mm diameter semiconductor grade silicon crystals

    NASA Astrophysics Data System (ADS)

    Lu, Zheng; Kimbel, Steven

    2011-03-01

    Research and development of the next generation 450 mm semiconductor grade silicon crystal and related technology have been carried out in MEMC following the company's philosophy to stay one generation ahead on research and development. The first 450 mm dislocation free crystal was grown in early 2009 and the first 450 mm semiconductor wafer was produced shortly after. General challenges in crystal growth process, puller, and hot zone designs, as well as control, automation, and handling are discussed in this paper. General considerations on working with customers and equipment manufacturers on fundamental crystal and wafer quality characteristics are also discussed.

  4. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Default Factors for Petroleum Products... Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table MM-1 Table MM-1 to Subpart MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric...

  5. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Default Factors for Petroleum Products... Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table MM-1 Table MM-1 to Subpart MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric...

  6. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Default Factors for Petroleum Products... Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table MM-1 Table MM-1 to Subpart MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric...

  7. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Factors for Petroleum Products... Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table MM-1 Table MM-1 to Subpart MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric...

  8. Sporadic Creutzfeldt-Jakob Disease MM1+2C and MM1 are Identical in Transmission Properties.

    PubMed

    Kobayashi, Atsushi; Matsuura, Yuichi; Iwaki, Toru; Iwasaki, Yasushi; Yoshida, Mari; Takahashi, Hitoshi; Murayama, Shigeo; Takao, Masaki; Kato, Shinsuke; Yamada, Masahito; Mohri, Shirou; Kitamoto, Tetsuyuki

    2016-01-01

    The genotype (methionine, M or valine, V) at polymorphic codon 129 of the PRNP gene and the type (1 or 2) of abnormal prion protein in the brain are the major determinants of the clinicopathological features of sporadic Creutzfeldt-Jakob disease (CJD), thus providing molecular basis for classification of sporadic CJD, that is, MM1, MM2, MV1, MV2, VV1 or VV2. In addition to these "pure" cases, "mixed" cases presenting mixed neuropathological and biochemical features have also been recognized. The most frequently observed mixed form is the co-occurrence of MM1 and MM2, namely MM1+2. However, it has remained elusive whether MM1+2 could be a causative origin of dura mater graft-associated CJD (dCJD), one of the largest subgroups of iatrogenic CJD. To test this possibility, we performed transmission experiments of MM1+2 prions and a systematic neuropathological examination of dCJD patients in the present study. The transmission properties of the MM1+2 prions were identical to those of MM1 prions because MM2 prions lacked transmissibility. In addition, the neuropathological characteristics of MM2 were totally absent in dCJD patients examined. These results suggest that MM1+2 can be a causative origin of dCJD and causes neuropathological phenotype similar to that of MM1.

  9. Growth kinetics of 1-2 mm and 3-4 mm colonies of Nostoc sphaeroides (Cyanophyta) in outdoor culture.

    PubMed

    Deng, Zhongyang; Yan, Chunlan; Lu, Fan; Hu, Qiang; Hu, Zhengyu

    2008-10-01

    Nostoc sphaeroides Kützing was cultivated in paddlewheel-driven raceway ponds and the growth kinetics of 1-2 mm and 3-4 mm colonies of N. sphaeroides was studied. The biomass productivities in 2.5 m(2) raceway ponds inoculated with 1-2 mm and 3-4 mm colonies were 5.2 and 0.25 g dry wt m(-2) d(-1), respectively. Furthermore, differently sized colonies showed different relative water content, total soluble carbohydrates, chlorophyll a content and density of filaments. This is the first report on mass culture of N. sphaeroides under outdoor conditions.

  10. Photodynamic therapy for Barrett's esophagus using a 20-mm diameter light-delivery balloon

    NASA Astrophysics Data System (ADS)

    Panjehpour, Masoud; Overholt, Bergein F.; Phan, Mary N.; Haydek, John M.; Robinson, Amy R.

    2002-06-01

    Background and Objective: Patients with high grade dysplasia (HGD) in Barrett's esophagus are at a high risk for developing esophageal adenocarcinoma. Esophagectomy is the standard treatment for such patients. The objective of this study was to evaluate the safety and efficacy of photodynamic therapy (PDT) using an improved light delivery balloon for ablation of Barrett's esophagus with high grade dysplasia and/or early cancer. Materials and Methods: 20 patients with HGD or early cancer (19 with HGD, 1 with T1 cancer) received 2 mg/kg of porfimer sodium, intravenously. Two to three days after the injection, laser light was delivered using a cylindrical diffuser inserted inside a 20-mm diameter reflective esophageal PDT balloon. Initially, the balloon was inflated to a pressure of 80 mm Hg. The balloon pressure was gradually reduced to 30 mm Hg. A KTP/dye laser at 630 nm was used as the light source. Light dose of 115 J/cm was delivered at an intensity of 270 mw/cm. Nodules were pre- treated with an extra 50 J/cm using a short diffuser inserted through the scope. Patients were maintained on PPI therapy to keep the gastric pH higher than 4. Eighteen patients required one treatment, while two patients were treated twice. Follow-up consisted of endoscopy with four quadrant biopsies at every 2 cm of the treated area. Thermal ablation was used to treat small residual islands on the follow-ups. The follow-up endoscopies ranged from 6 to 17 months. Results: On follow-up endoscopy, 12 patients had complete replacement of their Barrett's mucosa with neosquamous mucosa. Five patients had residual non-dysplastic Barrett's mucosa, one had indefinite dysplasia, two had low grad dysplasia. There were no residual HGD or cancers. The average length of Barrett's was reduced from 5.4 cm to 1.2 cm. High balloon pressure resulted in wide variation in PDT response among patients. Lower balloon pressures resulted in more consistent destruction of Barrett's mucosa among patients. Five

  11. Ultrasonic micro-motor using miniature piezoelectric tube with diameter of 1.0 mm.

    PubMed

    Zhang, Hui; Dong, Shu-xiang; Zhang, Shu-yi; Wang, Tian-hua; Zhang, Zhong-ning; Fan, Li

    2006-12-22

    At the present moment, the smallest piezoelectric ultrasonic micro-motors utilizing miniature PZT piezoelectric ceramic tubes were developed. The motor consists of a PZT-metal composite tube stator, two steel rotors and a thin shaft that keeps the two rotors pressing on both ends of the stator elastically. The dimensions of the PZT tube are 1.0 mm in outer diameter, 0.6 mm in inner diameter and 5.0 mm in length. The diameter and total length of the assembled micro-motor is 1.0 mm and 8 mm (including an adjusting spring), respectively. The tube-type micro-motor is driven by two pairs of alternative voltages with phase shift 90 degrees between the adjacent electrodes and operated in the first circular-bending vibration mode of the stator with the resonance frequency about 58 kHz. The experimental results show that the tube-type micro-motors have perfect performances: (i) high rotation frequency over 3000 rpm and (ii) large starting torque over 7.8 microN m under the conditions of the input voltage of 110 V(p-p) and the resonance frequency. The micro-motor is well suitable for operating in micro-spaces, such as in intravascular, micro-robots and micro-craft applications.

  12. Ultra-Compact Multitip Scanning Probe Microscope with an Outer Diameter of 50 mm

    NASA Astrophysics Data System (ADS)

    Cherepanov, Vasily; Zubkov, Evgeny; Junker, Hubertus; Korte, Stefan; Blab, Marcus; Coenen, Peter; Voigtländer, Bert

    We present a multitip scanning tunneling microscope (STM) where four independent STM units are integrated on a diameter of 50 mm. The coarse positioning of the tips is done under the control of an optical microscope or an SEM in vacuum. The heart of this STM is a new type of piezoelectric coarse approach called Koala Drive which can have a diameter greater than 2.5 mm and a length smaller than 10 mm. Alternating movements of springs move a central tube which holds the STM tip or AFM sensor. This new operating principle provides a smooth travel sequence and avoids shaking which is intrinsically present for nanopositioners based on inertial motion with saw tooth driving signals. Inserting the Koala Drive in a piezo tube for xyz-scanning integrates a complete STM inside a 4 mm outer diameter piezo tube of <10 mm length. The use of the Koala Drive makes the scanning probe microscopy design ultra-compact and accordingly leads to a high mechanical stability. The drive is UHV, low temperature, and magnetic field compatible. The compactness of the Koala Drive allows building a four-tip STM as small as a single-tip STM with a drift of <0.2 nm/min and lowest resonance frequencies of 2.5 (xy) and 5.5 kHz (z). We present examples of the performance of the multitip STM designed using the Koala Drive.

  13. Use of 5-mm-diameter implants: Periotest values related to a clinical and radiographic evaluation.

    PubMed

    Aparicio, C; Orozco, P

    1998-12-01

    A modified design of the original Brånemark implant consisting of a cp. Titanium 5.0-mm-diameter self-tapping implant threaded up to the marginal platform has been proposed for specific indications. From February 1992 to November 1995, a total of 185 machined screw implants (Nobel Biocare, Gothenburg, Sweden) were installed in 45 patients to withstand 58 prostheses. Of these, 91 were 3.75-mm diameter and 94 were 5.0-mm wide. Most of the implants were placed in type B and C bone quantity and type 2 and 3 bone quality. A retrospective evaluation with regard to indications, marginal bone remodelling, Periotest values (PTv) and survival rate is presented. PTv and radiographic measurements were made at abutment connection and repeated 3, 6 and 12 months later and thereafter every year. The follow-up ranged from 16 to 55 months (mean 32.9 months) post-loading. Three patients with 8 5.0-mm implants dropped-out of the study at different stages. Out of the wide implants, 1 was expelled during the healing period; 3 were found mobile at the abutment connection; 1 lost its osseointegration suddenly after 2 years of function; 4 belonging to 1 patient did not meet the success criteria due to continuous marginal bone loss. The cumulative success rate of 5.0-mm implants (CSR) after 1 year of function was 97.2% for upper jaws and 88.4% in mandibles, whereas the CSR in maxilla after 48 months was 97.2% and 83.4% in mandibles. The obtained PTv from 5.0-mm-wide fixtures in maxilla and mandibles were respectively 1.1 and 0.6 units lower than those obtained PTv for 3.75-mm-diameter implants in the same patients. The hypothesis that there are differences in the damping capacity of the bone surrounding a 5.0-mm-wide implant compared to the 3.75-mm-diameter implant is supported by the PTv results.

  14. A 2.5-mm diameter probe for photoacoustic and ultrasonic endoscopy

    PubMed Central

    Yang, Joon-Mo; Chen, Ruimin; Favazza, Christopher; Yao, Junjie; Li, Chiye; Hu, Zhilin; Zhou, Qifa; Shung, K. Kirk; Wang, Lihong V.

    2012-01-01

    We have created a 2.5-mm outer diameter integrated photo-acoustic and ultrasonic mini-probe which can be inserted into a standard video endoscope’s instrument channel. A small-diameter focused ultrasonic transducer made of PMN-PT provides adequate signal sensitivity, and enables miniaturization of the probe. Additionally, this new endoscopic probe utilizes the same scanning mirror and micromotor-based built-in actuator described in our previous reports; however, the length of the rigid distal section of the new probe has been further reduced to ~35 mm. This paper describes the technical details of the mini-probe and presents experimental results that both quantify the imaging performance and demonstrate its in vivo imaging capability, which suggests that it could work as a mini-probe for certain clinical applications. PMID:23188360

  15. Characterization of the 80-mm diameter Hamamatsu PMTs for the KM3NeT project

    SciTech Connect

    Aiello, S.; Giordano, V.; Leonora, E.; Classen, L.; Reubelt, J.; Peek, H.; Visser, E.; Samtleben, D.; Kalekin, Oleg Collaboration: KM3NeT Collaboration

    2014-11-18

    The optical module designed for the KM3NeT project consists of 31 photomultipliers of 3-inch diameter housed into a 17-inch diameter glass sphere. A proposed photomultiplier was the R12199-02 Hamamatsu 80-mm diameter. 203 of such PMTs have been delivered from Hamamatsu and tested by the KM3NeT groups of NIKHEF-Amsterdam, ECAP-Erlangen and INFN-Catania. Tests have been performed to measure the main parameters, such as gain, transit time spread, dark pulses rate, fraction of spurious pulses, quantum efficiency and effective photocathode size. The main results matched with the requirements of the project. Methods and results are presented in this report.

  16. 200-mm-diameter neutral beam source based on inductively coupled plasma etcher and silicon etching

    SciTech Connect

    Kubota, Tomohiro; Nukaga, Osamu; Ueki, Shinji; Sugiyama, Masakazu; Inamoto, Yoshimasa; Ohtake, Hiroto; Samukawa, Seiji

    2010-09-15

    The authors developed a neutral beam source consisting of a 200-mm-diameter inductively coupled plasma etcher and a graphite neutralization aperture plate based on the design of a neutral beam source that Samukawa et al. [Jpn. J. Appl. Phys., Part 2 40, L779 (2001)] developed. They measured flux and energy of neutral particles, ions, and photons using a silicon wafer with a thermocouple and a Faraday cup and calculated the neutralization efficiency. An Ar neutral beam flux of more than 1 mA/cm{sup 2} in equivalent current density and a neutralization efficiency of more than 99% were obtained. The spatial uniformity of the neutral beam flux was within {+-}6% within a 100 mm diameter. Silicon etching using a F{sub 2}-based neutral beam was done at an etch rate of about 47 nm/min, while Cl{sub 2}-based neutral beam realized completely no undercut. The uniformity of etch rate was less than {+-}5% within the area. The etch rate increased by applying bias power to the neutralization aperture plate, which shows that accelerated neutral beam was successfully obtained. These results indicate that the neutral beam source is scalable, making it possible to obtain a large-diameter and uniform neutral beam, which is inevitable for application to mass production.

  17. Influence of Berdan and Boxer Primer Spit-Hole Diameter on 7.62-mm Cartridge Performance

    DTIC Science & Technology

    2014-06-01

    Influence of Berdan and Boxer Primer Spit-Hole Diameter on 7.62-mm Cartridge Performance by John J. Ritter ARL-TR-6968 June 2014...Influence of Berdan and Boxer Primer Spit-Hole Diameter on 7.62-mm Cartridge Performance John J. Ritter Weapons and Materials Research Directorate...2013–January 2014 4. TITLE AND SUBTITLE Influence of Berdan and Boxer Primer Spit-Hole Diameter on 7.62-mm Cartridge Performance 5a. CONTRACT

  18. An 8-mm diameter fibre robot positioner for massive spectroscopy surveys

    NASA Astrophysics Data System (ADS)

    Fahim, N.; Prada, F.; Kneib, J. P.; Glez-de-Rivera, G.; Hörler, P.; Sánchez, J.; Azzaro, M.; Becerril, S.; Bleuler, H.; Bouri, M.; Castaño, J.; Garrido, J.; Gillet, D.; Gómez, C.; Gómez, M. A.; González-Arroyo, A.; Jenni, L.; Makarem, L.; Yepes, G.; Arrillaga, X.; Carrera, M. A.; Diego, R.; Charif, M.; Hug, M.; Lachat, C.

    2015-06-01

    Massive spectroscopic survey are becoming trendy in astrophysics and cosmology, as they can address new fundamental knowledge such as understanding the formation of the Milky Way and probing the nature of the mysterious dark energy. To enable massive spectroscopic surveys, new technology has been developed to place thousands of optical fibres at a given position on a focal plane. This technology needs to be: (1) accurate, with micrometer positional accuracy; (2) fast to minimize overhead; (3) robust to minimize failure; and (4) low cost. In this paper, we present the development, properties, and performance of a new single 8-mm in diameter fibre positioner robot, using two 4-mm DC-brushless gearmotors, that allows us to achieve accuracies up to 0.07 arcsec (5 μm). This device has been developed in the context of the Dark Energy Spectroscopic Instrument.1

  19. Fabrication of 200 mm Diameter Sintering Body of Skutterudite Thermoelectric Material by Spark Plasma Sintering

    NASA Astrophysics Data System (ADS)

    Tomida, T.; Sumiyoshi, A.; Nie, G.; Ochi, T.; Suzuki, S.; Kikuchi, M.; Mukaiyama, K.; Guo, J. Q.

    2016-11-01

    Filled skutterudite is a promising material for thermoelectric power generation because its ZT value is relatively high. However, mass production of high-performance thermoelectric materials remains a challenge. This study focused on the sintering process of thermoelectric materials. Large-diameter n-type (Yb or La, Ca, Al, Ga, In)0.8(Co, Fe)4Sb12 skutterudite sintering bodies with a small thickness were successfully produced by the spark plasma sintering (SPS) method. When direct current flows through the thermoelectric sintering body during the SPS pulse, the Peltier effect causes a temperature difference within the sintering body. To eliminate the Peltier effect, an electrical insulating material was inserted between the punch (electrode) and the sintering body. In this way, an n-type La-filled skutterudite sample with a diameter of 200 mm, thickness of 21 mm, and weight of 5 kg was successfully produced. The thermoelectric properties and microstructures of the sample were almost the same throughout the whole sintering body, and the dimensionless figure of merit reached 1.0 at 773 K.

  20. Construction and manufacturing of a microgearhead with 1.9-mm outer diameter for universal application

    NASA Astrophysics Data System (ADS)

    Thuerigen, Christian; Beckord, Ulrich; Bessey, Reiner

    1999-03-01

    Many new applications in medicine, telecommunication, automation systems etc. require powerful microdrives. Speeds up to 100.000 rpm and output torques in the (mu) Nm-range are typical characteristics of electromagnetic micromotors with diameters of a few millimeters. To accomplish a powerful microdrive, these micromotors have to be combined with micro gearheads of the same outer diameter. For such a micro gearhead with toothed wheels manufactured by use of the LIGA process a multi-stage planetary gear has many advantages. Many stages with different gear ratios can be combined to achieve a great number of different transmission, but manufacturing tolerances and a clearance for assembly must be respected. Therefore besides the selection of a reliable gearhead type and a suitable manufacturing process the optimization of the tooth profile is the key to the implementation of powerful micro gear systems with high output torques and efficiencies. The involute profile is the most suitable toothing, but many calculations and simulations are required to find the right modulus, total depth of teeth, profile offset etc. In a joint project Dr. Fritz Faulhaber GmbH and Co. KG and the Institut fuer Mikrotechnik Mainz GmbH developed a powerful microdevice with an outer diameter of only 1.9 mm.

  1. MM1+2C sporadic Creutzfeldt-Jakob disease presenting as rapidly progressive nonfluent aphasia.

    PubMed

    Allegri, Ricardo F; Bartoloni, Leonardo; Iturry, Mónica; Romero, Carlos; Begué, Christián; Sevlever, Gustavo; Taratuto, Ana Lía

    2014-01-01

    We report a 77-year-old man, presenting with progressive aphasia as an initial symptom, who developed severe dementia over the course of 20 months. Frontal cortex PrPSc western blot was type 2 and codon 129 was MM; brain neuropathology showed cortical vacuoles with perivacuolar PrP immunostaining characteristic of MM2C. Cerebellum showed focal coarse, patchy staining in different sections of the molecular layer, diffuse fine punctuate and coarse PrP immunopositive deposits in the granule cell layer, and focal synaptic immunostaining in the molecular layer, suggestive of MM1+2C by histotyping. This clinical presentation has not yet been described in an MM1+2C subtype by histotyping.

  2. Cylinder-shaped ultrasonic motors 4.8 mm in diameter using electroactive piezoelectric materials

    NASA Astrophysics Data System (ADS)

    Luo, Laihui; Zhu, Hua; Zhao, Chunsheng; Wang, Haixia; Luo, Haosu

    2007-01-01

    Two cylinder-shaped ultrasonic motors 4.8mm in diameter were developed. This kind of motor was driven by four pieces of piezoelectric materials, which were used to excite the two first-bending vibrations. Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMNT) crystal and Pb(Zr ,Ti)O3 (PZT) ceramic piezoelectric materials were used as drive elements. The motor based on PMNT crystals could operate at a voltage of 25Vp-p (peak to peak). When driven by a 100Vp-p voltage, the motor could run at frequency ranging from 26to68kHz and the revolution speed reached 450rpm. Its maximum output torque was 0.6mNm. The motor based on the PZT ceramic did not exhibit high performance as the PMNT crystal motor. The piezoelectric materials affect the performance of the motors greatly.

  3. Efficacy of silodosin in the treatment of distal ureteral stones 4 to 10 mm in diameter

    PubMed Central

    Yuksel, Mustafa; Yilmaz, Serdar; Tokgoz, Husnu; Yalcinkaya, Soner; Baş, Serkan; Ipekci, Tümay; Yildiz, Ali; Ates, Nihat; Savas, Murat

    2015-01-01

    Purpose: Few studies have investigated the efficacy of silodosin, a recently introduced selective alpha 1-A adrenoceptor antagonist, in medical expulsive therapy (MET) for ureteral calculi. The results of these studies, which all evaluated the efficacy of 8 mg/day, indicate that silodosin is a potential treatment for ureteral calculi. This study investigated the efficacy of 4 mg/day of silodosin for MET of distal ureteral stones 4 to 10 mm in diameter. Material and Method: After 70 patients had been randomized into 2 groups of 35 patients each, both the control and experimental groups (groups 1 and 2, respectively) were advised to take 75 mg/day of diclofenacsodiumas needed for pain relief but only the experimental group to take 4 mg/day of silodosin. After 21 days, the groups were compared regarding the stone expulsion rate and duration, number of renalcolicepisodes, and analgesicdosage. Results: The median expulsion rates were 71.4% and 91.4% in groups 1 and 2, respectively, and the difference between them was significant (P=0.031). The median expulsion durations were 12.91±6.14 and 8.03±4.99 days, respectively, and the difference between them was significant (P<0.001). No significant differences were found regarding the median number of renal colic episodes or median analgesic dosage. While no patients in group 1 experienced side effects, 5 patients (14%) in group 2 experienced retrograde ejaculation. Conclusion: These results indicate that 4 mg/day of silodos in facilitates the expulsion of distal ureteral stones 4 to 10 mm in diameter but does not significantly reduce the number of renal colic episodes or analgesic dosage. PMID:26770537

  4. 50 mm Diameter digital DC/pulse neutron generator for subcritical reactor test

    NASA Astrophysics Data System (ADS)

    Li, Gang; Zhang, Zhong-Shuai; Chi, Qian; Liu, Lin-Mao

    2012-11-01

    A 50 mm diameter digital DC/pulse neutron generator was developed with 25 mm ceramic drive-in target neutron tube. It was applied in the subcritical reactor test of China Institute of Atomic Energy (CIAE). The generator can produce neutron in three modes: DC, pulse and multiple pulse. The maximum neutron yield of the generator is 1 × 108 n/s, while the maximum pulse frequency is 10 kHz, and the minimum pulse width is 10 μs. As a remote controlled generator, it is small in volume, easy to be connected and controlled. The tested results indicate that penning ion source has the feature of delay time in glow discharge, and it is easier for glow discharge to happen when switching the DC voltage of penning ion source into pulse. According to these two characteristics, the generator has been modified. This improved generator can be used in many other areas including Prompt Gamma Neutron Activation Analysis (PGNAA), neutron testing and experiment.

  5. The study of 700mm-diameter primary mirror based on topology optimization and sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Wang, Xin; He, Xiaoying; Jing, Juanjuan; Feng, Lei; Zhou, Jinsong; Wang, Wei; Li, Yacan; Wei, Lidong

    2016-10-01

    The primary mirror is an important optical component of space camera. Its performance related to the optical image quality, and the weight directly affects the whole camera weight. The traditional design of primary mirror relies on much experience, lacking of precise theory, and many design parameters obtained by empirical formulas, thus the performance of the result is unstable. For this study, a primary mirror made of SiC with the diameter of 700mm was conceptual designed to get the optimized structure. Then sensitivity analysis was carried out to determine the optimum thickness of the back muscles. Finally, the optimum primary mirror fully satisfied the required was completed, with outstanding mechanical performance and light weight. A comparison between the optimum primary and traditional primary was performed and the results showed that the optimum primary has higher lightweight ratio increased by 5%, higher modal frequency increased by 81Hz.The maximum deformation under gravity reduced by 48nm, PV of the mirror surface reduced by 8.1nm and RMS reduced by 3.1nm. All the results indicated that the optimization method in the paper is reasonable and effective, which gives a reference to the primary mirror design in the future.

  6. A simple multi-seeding approach to growth of large YBCO bulk with a diameter above 53 mm

    NASA Astrophysics Data System (ADS)

    Tang, Tian-wei; Wu, Dong-jie; Wu, Xing-da; Xu, Ke-Xi

    2015-12-01

    A successful simple multi-seeding approach to growing large size Y-Ba-C-O (YBCO) bulks is reported. Compared with the common single seeding method, our multi-seeding method is more efficient. By using four SmBa2Cu3O7-δ (Sm-123) seeds cut from a large size Sm-Ba-C-O (SmBCO) single domain, large YBCO samples up to 53 mm in diameter could be produced successfully and 100 mm diameter samples can also be grown. Experimental results show that the processing time can be shortened greatly by using this new approach, and the superconducting properties can also be improved. The Hall probe mapping shows that the trapped field distribution of 53 mm diameter multi-seeded sample is homogeneous and the peak value is up to 0.53 T. The magnetic levitation force density reaches to 14.7 N/cm2 (77 K, 0.5 T).

  7. Oesophageal heat exchangers with a diameter of 11mm or 14.7mm are equally effective and safe for targeted temperature management

    PubMed Central

    Guschlbauer, Maria; Maul, Alexandra C.; Cremer, Daniel A.; Becker, Ingrid; de la Puente Bethencourt, David; Paal, Peter; Padosch, Stephan A.; Wetsch, Wolfgang A.; Annecke, Thorsten; Böttiger, Bernd W.; Sterner-Kock, Anja; Herff, Holger

    2017-01-01

    Background Targeted temperature management (TTM) is widely used in critical care settings for conditions including hepatic encephalopathy, hypoxic ischemic encephalopathy, meningitis, myocardial infarction, paediatric cardiac arrest, spinal cord injury, traumatic brain injury, ischemic stroke and sepsis. Furthermore, TTM is a key treatment for patients after out-of-hospital cardiac-arrest (OHCA). However, the optimal cooling method, which is quick, safe and cost-effective still remains controversial. Since the oesophagus is adjacent to heart and aorta, fast heat-convection to the central blood-stream could be achieved with a minimally invasive oesophageal heat exchanger (OHE). To date, the optimal diameter of an OHE is still unknown. While larger diameters may cause thermal- or pressure-related tissue damage after long-term exposure to the oesophageal wall, smaller diameter (e.g., gastric tubes, up to 11mm) may not provide effective cooling rates. Thus, the objective of the study was to compare OHE-diameters of 11mm (OHE11) and 14.7mm (OHE14.7) and their effects on tissue and cooling capability. Methods Pigs were randomized to OHE11 (N = 8) or OHE14.7 (N = 8). After cooling, pigs were maintained at 33°C for 1 hour. After 10h rewarming, oesophagi were analyzed by means of histopathology. The oesophagus of four animals from a separate study that underwent exactly the identical preparation and cooling protocol described above but received a maintenance period of 24h were used as histopathological controls. Results Mean cooling rates were 2.8±0.4°C°C/h (OHE11) and 3.0±0.3°C °C/h (OHE14.7; p = 0.20). Occasional mild acute inflammatory transepithelial infiltrates were found in the cranial segment of the oesophagus in all groups including controls. Deviations from target temperature were 0.1±0.4°C (OHE11) and 0±0.1°C (OHE14.7; p = 0.91). Rewarming rates were 0.19±0.07°C °C/h (OHE11) and 0.20±0.05°C °C/h (OHE14.7; p = 0.75). Conclusions OHE with diameters

  8. Three-degree-of-freedom ultrasonic motor using a 5-mm-diameter piezoelectric ceramic tube.

    PubMed

    Mingsen Guo; Junhui Hu; Hua Zhu; Chunsheng Zhao; Shuxiang Dong

    2013-07-01

    A small three-degree-of-freedom ultrasonic motor has been developed using a simple piezoelectric lead zirconate titanate (PZT)-tube stator (OD 5 mm, ID 3 mm, length 15 mm). The stator drives a ball-rotor into rotational motion around one of three orthogonal (x-, y-, and z-) axes by combing the first longitudinal and second bending vibration modes. A motor prototype was fabricated and characterized; its performance was superior to those of previous motors made with a PZT ceramic/metal composite stator of comparable size. The method for further improving the performance was discussed. The motor can be further miniaturized and it has potential to be applied to medical microrobots, endoscopes or micro laparoscopic devices, and cell manipulation devices.

  9. Thermal mapping of Ceres at 1.2 mm with ALMA

    NASA Astrophysics Data System (ADS)

    Moullet, Arielle; Li, Jian-Yang; Titus, Timothy N.; Sykes, Mark V.; Ip, Wing-Huen; Lai, Ian-Lin

    2016-10-01

    Ceres' thermal emission distribution, which can be characterized through observations at IR and longer wavelengths, is indicative of radiative and physical properties of its surface such as thermal inertia and roughness. High-resolution maps from the Dawn mission now provide an exquisite geographic and geological context for the interpretation of temperature features, which are at large not accessible to the spacecraft's instruments. In particular, the presence of hydrated minerals and distinctive geological features suggest the existence of ice water reservoirs near the surface, which may be characterized through the analysis of thermal inertia distributions.We report on observations obtained in Fall 2015 at the Atacama Large Millimeter Array (ALMA), sampling most of the rotation of Ceres and hence allowing one to disentangle local-hour effects from geographical thermal features. The observations were performed during the 2015 Long Baseline Campaign, offering baselines as long as 10 km and yielding a spatial resolution down to 30 mas (~45 km at the equator). At the observed wavelength of 1.2 mm, the thermal emission probes both the emission from the surface and from deeper layers, down to the level of the diurnal skin depth, hence accessing regions where water ice could be stable.We will describe the diurnal and latitudinal temperature variations derived from our observations as well as preliminary results from thermal modeling in terms of subsurface thermal inertia and ice table latitudinal extent. This work is supported by the NASA Solar System Observations Program grant NNX15AE02G.

  10. Design and performance of a parachute recovery system to recover 155-mm- and 8-inch-diameter artillery shells

    SciTech Connect

    Waye, D.E.; Peterson, C.W.; Botner, W.T.

    1986-01-01

    A parachute recovery system has been developed and demonstrated for the recovery of 155-mm- and 8-inch-diameter artillery shells. The recovery system functions after being subjected to gun launch accelerations of up to 18,000 g's axially and up to 400,000 rad/sec/sup 2/ radially. The parachute is deployed while the shell is still spinning at about 250 revolutions per second. To deploy the parachute while the shell is spinning, a double-swivel system was developed. The deployment signal for the recovery system is provided by an electronic timer. Over 250 tests have been performed on both the 155-mm- and 8-inch-diameter artillery shell. Impact velocities are between 100 and 120 feet per second. The latest version of the recovery systems has been proven to be over 95% successful for the recovery of 8-inch-diameter artillery shells and over 85% successful for the recovery of 155-mm-diameter artillery shells.

  11. Design and evaluation of coils for a 50 mm diameter induction coilgun launcher

    SciTech Connect

    Kaye, R.J.; Shokair, I.R.; Wavrik, R.W.; Dempsey, J.F.; Honey, W.E.; Shimp, K.J.; Douglas, G.M.

    1993-12-31

    Coilguns have the ability to provide magnetic pressure to projectiles which results in near constant acceleration. However, to achieve this performance and control projectile hearing, significant constraints are placed on the design of the coils. We are developing coils to produce an effective projectile base pressure of 100 MPa (1kbar) as a step toward reaching base pressures of 200 MPa. The design uses a scalable technology applicable to the entire range of breech to muzzle coils of a multi-stage launcher. This paper presents the design of capacitor-driven coils for launching nominal 50 mm, 350 gram projectiles. Design criteria, constraints, mechanical stress analysis, launcher performance, and test results are discussed.

  12. Design and fabrication of CGH for 600mm diameter SiC primary mirror surface figure testing

    NASA Astrophysics Data System (ADS)

    Pang, Zhihai; Ma, Zhen; Fan, Xuewu; Zou, Gangyi

    2016-09-01

    Computer-generated hologram (CGH) is an effective way to compensate wavefront aberration in null test of aspheric surfaces and freeform surfaces. Our strategies of CGH design for 600mm diameter SiC primary mirror surface figure testing are presented, and an experiment demonstrating the compensation test results of CGH is reported. We design a CGH including two sections on the same substrate in order to align the CGH to the incident wavefront: main section for compensating wavefront in null test, alignment section for adjusting the relative position between CGH and interferometer. In order to isolate different orders of diffraction, we used power carrier to make different orders of diffraction come to focus at different position along the axis to avoid ghost reflections. We measured the 600mm diameter SiC primary mirror using this CGH, and the surface test result is 0.033λ rms.

  13. 4-mm-diameter three-dimensional imaging endoscope with steerable camera for minimally invasive surgery (3-D-MARVEL).

    PubMed

    Bae, Sam Y; Korniski, Ronald J; Shearn, Michael; Manohara, Harish M; Shahinian, Hrayr

    2017-01-01

    High-resolution three-dimensional (3-D) imaging (stereo imaging) by endoscopes in minimally invasive surgery, especially in space-constrained applications such as brain surgery, is one of the most desired capabilities. Such capability exists at larger than 4-mm overall diameters. We report the development of a stereo imaging endoscope of 4-mm maximum diameter, called Multiangle, Rear-Viewing Endoscopic Tool (MARVEL) that uses a single-lens system with complementary multibandpass filter (CMBF) technology to achieve 3-D imaging. In addition, the system is endowed with the capability to pan from side-to-side over an angle of [Formula: see text], which is another unique aspect of MARVEL for such a class of endoscopes. The design and construction of a single-lens, CMBF aperture camera with integrated illumination to generate 3-D images, and the actuation mechanism built into it is summarized.

  14. Record high-speed short-range transmission over 1 mm core diameter POF employing DMT modulation.

    PubMed

    Yang, H; Lee, S C J; Okonkwo, C M; Abraha, S T; van den Boom, H P A; Breyer, F; Randel, S; Koonen, A M J; Tangdiongga, E

    2010-03-01

    We report multigigabit/second transmission capacity in 1 mm core diameter graded index plastic optical fiber (POF) exploiting off-the-shelf low-cost components and discrete multitone (DMT) modulation. Transmission capacities of 10.1 Gbits/s x 15 m and 12.7 Gbits/s x 3 m are achieved for average bit-error rates less than 10(-3).

  15. 78 FR 41366 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 4 1/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-10

    ... International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure... antidumping duty order on certain large diameter carbon and alloy seamless standard, line, and pressure pipe... Pressure Pipe (Over 4 \\1/2\\ Inches) from Japan,'' dated concurrently with this notice (Preliminary...

  16. Characterization of 100 mm Diameter 4H-Silicon Carbide CrystalsWith Extremely Low Basal Plane Dislocation Density

    SciTech Connect

    M Dudley; N Zhang; Y Zhang; B Raghothamachar; S Byrappa; G Choi; E Drachev; M Loboda

    2011-12-31

    Synchrotron White Beam X-ray Topography (SWBXT) studies are presented of basal plane dislocation (BPD) configurations and behavior in a new generation of 100mm diameter, 4H-SiC wafers with extremely low BPD densities (3-4 x 10{sup 2} cm{sup -2}). The conversion of non-screw oriented, glissile BPDs into sessile threading edge dislocations (TEDs) is observed to provide pinning points for the operation of single ended Frank-Read sources. In some regions, once converted TEDs are observed to re-convert back into BPDs in a repetitive process which provides multiple BPD pinning points.

  17. Intercomparison of flatness measurements of an optical flat at apertures of up to 150 mm in diameter

    NASA Astrophysics Data System (ADS)

    Quabis, S.; Schulz, M.; Ehret, G.; Asar, M.; Balling, P.; Křen, P.; Bergmans, R. H.; Küng, A.; Lassila, A.; Putland, D.; Williams, D.; Pirée, H.; Prieto, E.; Pérez, M.; Svedova, L.; Ramotowski, Z.; Vannoni, M.; Hungwe, F.; Kang, Y.

    2017-02-01

    Recently, a scientific comparison of flatness measuring instruments at European National Metrology Institutes (NMIs) was performed in the framework of EURAMET. The specimen was a well-polished optical surface with a maximum measurement aperture of 150 mm in diameter. Here, we present an evaluation concept, which allows the determination of a mean flatness map taking into account different lateral resolutions of the instruments and different orientations of the specimen during measurement. We found that all measurements are in agreement with the mean flatness map within the uncertainty intervals stated by the participants. The aim of this scientific comparison is to specify an appropriate operation and evaluation procedure for future comparisons.

  18. Differential pressure response of 25-mm-diameter glass fiber filters challenged with coal and limestone dust mixtures.

    PubMed

    Dobroski, Harry; Tuchman, Donald P; Vinson, Robert P; Timko, Robert J

    2002-02-01

    This article summarizes results of research conducted by the National Institute for Occupational Safety and Health (NIOSH) at its Pittsburgh Research Laboratory. The objective of this work was to determine the correlation between the mass (M) of respirable coal and limestone dusts collected on 25-mm-diameter glass fiber filters mounted in cassettes and the increase in differential pressure (deltaP) that develops across the filters when drawing at constant air flow. Test aerosols were generated inside a laboratory dust chamber using various coal dusts, limestone dust, and mixes of the two. Dusts with different particle size distributions were deposited on the filters by sampling from the chamber through cyclone preclassifiers at different flow rates. Results show that the relationship between differential pressure increase (cm water) and dust mass (mg) is linear and can be approximated by the equation deltaP = KM. The K values (slopes) range from 1.14 to 1.64, depending on the parent coal of the samples. The influence of particle size distribution was also found. The overall K value for all the data summarized in this article is 1.35, with R2 = 0.84 for the summary equation. When calibrated for individual work sites, or other circumstances where great variability in dust characteristics is avoided, the relationship between collected dust mass and increase in differential pressure may provide an exploitable principle for measurement of respirable dust concentrations.

  19. High-speed intravascular spectroscopic photoacoustic imaging at 1000 A-lines per second with a 0.9-mm diameter catheter

    NASA Astrophysics Data System (ADS)

    Li, Yan; Gong, Xiaojing; Liu, Chengbo; Lin, Riqiang; Hau, William; Bai, Xiaosong; Song, Liang

    2015-06-01

    Intravascular spectroscopic photoacoustic technology can image atherosclerotic plaque composition with high sensitivity and specificity, which is critical for identifying vulnerable plaques. Here, we designed and engineered a catheter of 0.9 mm in diameter for intravascular photoacoustic (IVPA) imaging, smaller than the critical size of 1 mm required for clinical translation. Further, a quasifocusing photoacoustic excitation scheme was developed for the catheter, producing well-detectable IVPA signals from stents and lipids with a laser energy as low as ˜30 μJ/pulse. As a result, this design enabled the use of a low-energy, high-repetition rate, ns-pulsed optical parametric oscillator laser for high-speed spectroscopic IVPA imaging at both the 1.2-μm and 1.7-μm spectral bands for lipid detection. Specifically, for each wavelength, a 1-kHz IVPA A-line rate was achieved, ˜100-fold faster than previously reported IVPA systems offering a similar wavelength tuning range. Using the system, spectroscopic IVPA imaging of peri-adventitial adipose tissue from a porcine aorta segment was demonstrated. The significantly improved imaging speed, together with the reduced catheter size and multiwavelength spectroscopic imaging ability, suggests that the developed high-speed IVPA technology is of great potential to be further translated for in vivo applications.

  20. Estimation of position resolution for DOI-PET detector using diameter 0.2 mm WLS fibers

    SciTech Connect

    Kaneko, Naomi; Ito, Hiroshi; Kawai, Hideyuki; Kamada, Kei

    2015-07-01

    We have been developing sub mm resolution and $ 1 million DOI-PET detector using wavelength shifting fibers (WLSF), scintillation crystals of plate shape and SiPM (MPPC: HAMAMATSU K. K.). Conventional design of DOI-PET detector is obtained about mm{sup 3} of resolution by using some blocks detecting gamma-ray in mm 3 voxel. It requires the production cost of $ a few ten million or more for high technique of processing crystal and a lot of number of photo-devices, and this technology is reaching the limit of the resolution. Both higher resolution and lower cost of DOI-PET detector production is challenging for PET diagnosis population. We propose two type of detector. One is a whole body PET system, and the other for brain or small animal. Both PET system consist 6 blocks. the former consist of 6 layers 300 mm x 300 mm x 4 mm crystal plate. The latter consist 16 crystal layers, 4 x 4 crystal array. The size of crystal plate is 40 mm x 40 mm x 1 mm.The WLSF sheets connect to upper and lower plane. The whole PET systems connect 8 SiPMs are bonded on each side. For the brain PET, 9 WLSF fibers are bond on the each side. The expected position resolution maybe less than 1 mm at the former. We have estimation experimental performance the system using {sup 22}Na radioactive source. The collection efficiency of WLSF (R-3) sheet was achieved 10% with GAGG at 511 keV. The relation between reconstruction position and incident position is obtained linearity and achieved the resolution of 0.7 mm FWHM for x-axis of DOI by readout WLSF. (authors)

  1. On the applicability of the molecular-mechanical force field (MM2) scheme to the gauche oxygen effect characteristic of glycol ethers such as 1,2-dimethoxyethane, 1,2-dimethoxypropane and 1,2-dimethoxy-2-methylpropane

    NASA Astrophysics Data System (ADS)

    Abe, Akihiro; Tasaki, Kenzabu

    1986-07-01

    MM2 calculations have been carried out for a series of glycol ethers such as 1,2-dimethoxyethane (DME), 1,2-dimethoxypropane (DME) and 1,2-dimethoxy-2-methylpropane (DMMP). For DME, in accordance with the results of Baldwin [11], the observed energy of the gauche state ( Eσ = -0.5 kcal mol -1) for the OCCO bond is found to be approximately reproduced by the calculation when the dipole—dipole interaction term is suppressed by adopting a relatively large dielectric constant (ɛ eff = 7.5). With the same value of ɛ eff, the gauche energy of DMMP is calculated to be Eψ = —0.9 kcal mol -1, which is at variance with the observed value of 0.5 kcal mol -1. In DMP, the two gauche forms around the OCCO bond are non-equivalent, and the stability of the conformers varies in the order gα &>; t &>; gß. These experimental observations were not produced by the calculation. The MM2 program failed, in the state of the art, to provide an adequate explanation for the gauche oxygen effect observed in the aboved-mentioned glycol ethers as well as in there polymer analogs. It is pointed out that inclusion of an empirical correction term in the torsional potential for the individual rotational states offers a simple amendment which serves for practical purposes.

  2. Estimation of time resolution for DOI-PET detector using diameter 0.2 mm WLS fibers

    SciTech Connect

    Kobayashi, A.; Ito, H.; Han, S.; Kaneko, N.; Kawai, H.; Kodama, S.; Han, S.; Kamada, K.; Shoji, Y.; Yoshikawa, A.

    2015-07-01

    We are developing the whole-body PET detector with high position resolution (1 mm) and low cost (1 M dollars). Scintillator plates, Wave Length Sifting Fibers and SiPMs are used. In this work, time resolution of our PET detector is estimated. Our detector may also have good time resolution such as a few ps. (authors)

  3. Investigation of an 11mm diameter twin screw granulator: Screw element performance and in-line monitoring via image analysis.

    PubMed

    Sayin, Ridade; Martinez-Marcos, Laura; Osorio, Juan G; Cruise, Paul; Jones, Ian; Halbert, Gavin W; Lamprou, Dimitrios A; Litster, James D

    2015-12-30

    As twin screw granulation (TSG) provides one with many screw element options, characterization of each screw element is crucial in optimizing the screw configuration in order to obtain desired granule attributes. In this study, the performance of two different screw elements - distributive feed screws and kneading elements - was studied in an 11 mm TSG at different liquid-to-solid (L/S) ratios. The kneading element configuration was found to break large granules more efficiently, leading to narrower granule size distributions. While pharmaceutical industry shifts toward continuous manufacturing, inline monitoring and process control are gaining importance. Granules from an 11 mm TSG were analysed using the Eyecon™, a real-time high speed direct imaging system, which has been used to capture accurate particle size distribution and particle count. The size parameters and particle count were then assessed in terms of their ability to be a suitable control measure using the Shewhart control charts. d10 and particle count were found to be good indicators of the change in L/S ratio. However, d50 and d90 did not reflect the change, due to their inherent variability even when the process is at steady state.

  4. Comparison of retrograde intrarenal surgery and mini-percutaneous nephrolithotomy in management of lower-pole renal stones with a diameter of smaller than 15 mm.

    PubMed

    Kirac, Mustafa; Bozkurt, Ömer Faruk; Tunc, Lutfi; Guneri, Cagri; Unsal, Ali; Biri, Hasan

    2013-06-01

    The aim of this study was to compare the outcomes of retrograde intrarenal surgery (RIRS) and miniaturized percutaneous nephrolithotomy (mini-PNL) in management of lower-pole renal stones with a diameter smaller than 15 mm. Between December 2009 and July 2012, the patients with the diagnosis of lower-pole stones were evaluated by ultrasonography, intravenous pyelography and computed tomography. The records of 73 evaluable patients who underwent mini-PNL (n = 37) or RIRS (n = 36) for lower-pole (LP) stones with diameter smaller than 15 mm were reviewed retrospectively. Of the 73 patients, 37 underwent mini-PNL and 36 underwent RIRS. The stone-free rates were 89.1 and 88.8 % for mini-PNL and RIRS groups, respectively. The mean operation time was 53.7 ± 14.5 in the mini-PNL group but 66.4 ± 15.8 in the RIRS group (P = 0.01). The mean fluoroscopy times and hospitalization times were significantly higher in the mini-PNL group. There was no major complication in any patient. RIRS and mini-PNL are safe and effective methods for treatment of LP calculi with a diameter smaller than 15 mm. RIRS is a non-invasive and feasible treatment option, and has also short hospitalization time, low morbidity and complication rate. It may be an alternative of mini-PNL in the treatment LP calculi with smaller than 15 mm.

  5. Management of upper ureteral stones exceeding 15 mm in diameter: Shock wave lithotripsy versus semirigid ureteroscopy with holmium:yttrium–aluminum–garnet laser lithotripsy

    PubMed Central

    Aboutaleb, Hamdy; Omar, Mohamed; Salem, Shady; Elshazly, Mohamed

    2016-01-01

    Objectives: We conducted a retrospective study to evaluate the efficacy and outcome of shock wave lithotripsy versus semirigid ureteroscopy in the management of the proximal ureteral stones of diameter exceeding 15 mm. Methods: During the 2009−2014 study period, 147 patients presenting with the proximal ureteral stones exceeding 15 mm in diameter were treated. Both shock wave lithotripsy and ureteroscopy with laser lithotripsy were offered for our patients. A 6/8.9 Fr semirigid ureteroscope was used in conjunction with a holmium:yttrium–aluminum–garnet laser. The stone-free rate was assessed at 2 weeks and 3 months post-treatment. All patients were evaluated for stone-free status, operation time, hospital stay, perioperative complications, and auxiliary procedures. Results: Of the 147 patients who took part in this study, 66 (45%) had undergone shock wave lithotripsy and 81 (55%) underwent ureteroscopy. At the 3-month follow-up, the overall stone-free rate in the shock wave lithotripsy group was 39/66 (59%) compared to 70/81 (86.4%) in the ureteroscopic laser lithotripsy group. Ureteroscopic laser lithotripsy achieved a highly significant stone-free rate (p = 0.0002), and the mean operative time, auxiliary procedures, and postoperative complication rates were comparable between the two groups. Conclusion: In terms of the management of proximal ureteral stones exceeding 15 mm in diameter, ureteroscopy achieved a greater stone-free rate and is considered the first-line of management. Shock wave lithotripsy achieved lower stone-free rate, and it could be used in selected cases. PMID:28348743

  6. Useful receiver telescope diameter of ground-based and airborne 1-, 2-, and 10-micron coherent lidars in the presence of atmospheric refractive turbulence

    NASA Technical Reports Server (NTRS)

    Chan, Kin P.; Killinger, Dennis K.

    1992-01-01

    Calculations of the integrated effect of atmospheric refractive turbulence on 1-, 2-, and 10-micron coherent lidar performance are presented for a series of different lidar propagation geometries. The effective lidar receiver telescope diameter is evaluated for each case. The results indicate that atmospheric turbulence should not be a significant factor in the performance of a downward-looking high-altitude or satellite-borne coherent lidar system. It is also shown that ground-based 1-2-micron coherent lidars may be limited in their useful telescope aperture, especially for horizontal or nearly horizontal path measurements near the ground.

  7. Influence of power density on high purity 63 mm diameter polycrystalline diamond deposition inside a 2.45 GHz MPCVD reactor

    NASA Astrophysics Data System (ADS)

    Yu, Shengwang; Wang, Rong; Zheng, Ke; Gao, Jie; Li, Xiaojing; Hei, Hongjun; Liu, Xiaoping; He, Zhiyong; Shen, Yanyan; Tang, Bin

    2016-09-01

    63 mm diameter polycrystalline diamond (PCD) films were synthesized via a microwave plasma chemical vapor deposition (MPCVD) reactor in 99% H2-1% CH4 atmosphere. Two different conditions, i.e. the typical condition (input power of 5 kW and gas pressure of 13 kPa) and the high power density condition (input power of 10 kW and gas pressure of 18 kPa), were employed for diamond depositions. The color changes of the plasma under the two proposed conditions with and without methane were observed by photographs. Likewise, the concentrations of hydrogen atoms and carbon active chemical species in plasma were analyzed by optical emission spectroscopy (OES). The morphologies and purity of the PCD films were investigated by scanning electron microscopy (SEM) and Raman spectroscopy, respectively. Finally, the transmission spectrum of the polished PCD plates was characterized by a UV-Vis-NIR spectrometer. Experimental results showed that both the concentrations of hydrogen atoms and carbon radicals increased obviously, with the boost input power and higher pressure. The films synthesized under the high power density condition displayed higher purity and more uniform thickness. The growth rates in 10 kW and 18 kPa reached ~7.7 µm h-1, approximately 6.5 times as much as that occurred in the typical process. Moreover, the polished plates synthesized under the high power density condition possessed a relatively high optical transmittance (~69%), approaching the theoretical values of approximately 71.4% in IR. These results indicate that the purity and growth rate of big-area PCD films could be simultaneously increased with power density.

  8. Estimation of position resolution for DOI-PET detector using diameter 0.2 mm WLS fibers [ANIMMA--2015-IO-x5

    SciTech Connect

    Kaneko, Naomi; Ito, H.; Han, S.; Kawai, H.; Kodama, S.; Kobayashi, A.; Tabata, M.; Kamada, K.; Shoji, Y.; Yoshikawa, A.

    2015-07-01

    We have been developing a submillimeter resolution and low-cost DOI-PET detector using wavelength shifting fibers (WLSF), scintillating crystal plates and MPPCs (Hamamatsu Photonics). Conventional design of DOI-PET detectors had approximately mm{sup 3} of resolution by using some scintillating blocks with a volume of 1 mm{sup 3}, which detects gamma-ray. They are expensive due to difficulties in processing scintillating crystals and a large number of photo-detectors, and these technologies are likely to reach the limit of the resolution. Development of a lower cost DOI-PET detector with higher resolution is challenging to popularize the PET diagnosis. We propose two type of PET detector. One is a whole body PET system, and the other is a PET system for brain or small animals. Each PET system consists 6 blocks. The former consists of 6 layers of crystal plates with 300 mm x 300 mm x 4 mm. The latter consists of 16 crystal layers, forming 4 x 4 crystal arrays. The size of the crystal plate is 40 mm x 40 mm x 1 mm. Wavelength shifting fiber (WLSF) sheets are attached to above and up and down side of crystal planes. The whole PET system has 8 MPPCs attached on each side. For the brain PET detector, 9 WLSF fibers are attached on the each side. The expected position resolution would be less than 1 mm at the former system. We have performed an experimental performance estimation for the system component using {sup 22}Na radioactive source. We achieved a collection efficiency of 10% using the WLSF sheet and Ce:Gd{sub 3}(Al,Ga){sub 5}O{sub 12} (GAGG) crystals at 511 keV. The linear relationship between reconstruction position and incident position was obtained, and a resolution of 0.7 mm (FWHM) for x-axis of DOI by the WLSF readout was achieved. (authors)

  9. Acoustic and aerodynamic performance of a 1.83 meter (6 foot) diameter 1.2 pressure ratio fan (QF-6). [for short takeoff aircraft

    NASA Technical Reports Server (NTRS)

    Woodward, R. P.; Lucas, J. G.; Stakolich, E. G.

    1974-01-01

    A 1.2-pressure-ratio, 1.83-meter-(6-ft-) diameter experimental fan stage with characteristics suitable for use in STOL aircraft engines was tested for acoustic and aerodynamic performance. The design incorporated features for low noise, including absence of inlet guide vanes, low rotor-blade-tip speed, low aerodynamic blade loading, and long axial spacing between the rotor and stator rows. The stage was run with four nozzles of different area. The perceived noise along a 152.4 meter (500-ft) sideline was rear-quadrant dominated with a maximum design-point level of 103.9 PNdb. The acoustic 1/3-octave results were analytically separated into broadband and pure-tone components. It was found that the stage noise levels generally increase with a decrease in nozzle area, with this increase observed primarily in the broadband noise component. A stall condition was documented acoustically with a 90-percent-of-design-area nozzle.

  10. Demonstration of AlGaN/GaN high-electron-mobility transistors on 100 mm diameter Si(111) by plasma-assisted molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, K.; Dharmarasu, N.; Sun, Z.; Arulkumaran, S.; Ng, G. I.

    2010-12-01

    AlGaN/GaN high-electron-mobility transistor structures grown on 100 mm high-resistivity Si(111) substrates using plasma-assisted molecular beam epitaxy are reported. The two-dimensional electron gas (2DEG) formation in the heterostructures was realized by the growth optimization of two-step low temperature and high temperature AlN layers and GaN buffer layer. High-electron mobility of 1100 cm2/V s with a sheet carrier density of 9×1012 cm-2 was achieved. The presence of 2DEG in the AlGaN/GaN interface was confirmed by temperature dependent Hall measurements and capacitance-voltage carrier profiling. The fabricated 1.5 μm gate length high electron mobility transistor exhibited a maximum drain current density of 530 mA/mm and a peak extrinsic transconductance of 156 mS/mm.

  11. VizieR Online Data Catalog: 70um-1.2mm and N2H+ maps of IRDC18454 (W43) (Beuther+,

    NASA Astrophysics Data System (ADS)

    Beuther, H.; Tackenberg, J.; Linz, H.; Henning, T.; Krause, O.; Ragan, S.; Nielbock, M.; Launhardt, R.; Schmiedeke, A.; Schuller, F.; Carlhoff, P.; Nguyen-Luong, Q.; Sakai, T.

    2011-11-01

    The cloud complex with a size of ~6'x6' was observed with PACS on Herschel on 2010 March 9. Maps at 250, 350, and 500um were obtained with SPIRE 2010) on 2010 March 11. We observed IRDC18454-1 with the Plateau de Bure Interferometer during five nights in October and November 2009 at 93GHz in the C and D configurations. The N2H+ data has been observed using the BEARS receiver at the NRO 45m telescope in Nobeyama, Japan. The different velocity components have been observed one in April 2010 with an average system temperature of Tsys=206K, the second in June, at slightly lower Tsys. The MIPS 24um data (from MIPSGAL) as well as the IRAC 8um observations (from GLIMPSE) are taken from the Spitzer archive. The 1.2mm continuum data were first presented in Beuther et al. (2002, Cat. J/ApJ/566/945) and the APEX 870um data are part of the ATLASGAL survey of the Galactic plane (Schuller et al., 2009A&A...504..415S). (2 data files).

  12. The rates of wear of X3 highly cross-linked polyethylene at five years when coupled with a 36 mm diameter ceramic femoral head in young patients.

    PubMed

    Selvarajah, E; Hooper, G; Grabowski, K; Frampton, C; Woodfield, T B F; Inglis, G

    2015-11-01

    Polyethylene wear debris can cause osteolysis and the failure of total hip arthroplasty. We present the five-year wear rates of a highly cross-linked polyethylene (X3) bearing surface when used in conjunction with a 36 mm ceramic femoral head. This was a prospective study of a cohort of 100 THAs in 93 patients. Pain and activity scores were measured pre- and post-operatively. Femoral head penetration was measured at two months, one year, two years and at five years using validated edge-detecting software (PolyWare Auto). At a mean of 5.08 years (3.93 to 6.01), 85 hips in 78 patients were available for study. The mean age of these patients was 59.08 years (42 to 73, the mean age of males (n = 34) was 59.15 years, and females (n = 44) was 59.02 years). All patients had significant improvement in their functional scores (p < 0.001). The steady state two-dimensional linear wear rate was 0.109 mm/year. The steady state volumetric wear rate was 29.61 mm(3)/year. No significant correlation was found between rate of wear and age (p = 0.34), acetabular component size (p = 0.12) or clinical score (p = 0.74). Our study shows low steady state wear rates at five years in X3 highly cross-linked polyethylene in conjunction with a 36 mm ceramic femoral head. The linear wear rate was almost identical to the osteolysis threshold of 0.1 mm/year recommended in the literature.

  13. Non-invasive high-resolution tracking of human neuronal pathways: diffusion tensor imaging at 7T with 1.2 mm isotropic voxel size

    NASA Astrophysics Data System (ADS)

    Lützkendorf, Ralf; Hertel, Frank; Heidemann, Robin; Thiel, Andreas; Luchtmann, Michael; Plaumann, Markus; Stadler, Jörg; Baecke, Sebastian; Bernarding, Johannes

    2013-03-01

    Diffusion tensor imaging (DTI) allows characterizing and exploiting diffusion anisotropy effects, thereby providing important details about tissue microstructure. A major application in neuroimaging is the so-called fiber tracking where neuronal connections between brain regions are determined non-invasively by DTI. Combining these neural pathways within the human brain with the localization of activated brain areas provided by functional MRI offers important information about functional connectivity of brain regions. However, DTI suffers from severe signal reduction due to the diffusion-weighting. Ultra-high field (UHF) magnetic resonance imaging (MRI) should therefore be advantageous to increase the intrinsic signal-to-noise ratio (SNR). This in turn enables to acquire high quality data with increased resolution, which is beneficial for tracking more complex fiber structures. However, UHF MRI imposes some difficulties mainly due to the larger B1 inhomogeneity compared to 3T MRI. We therefore optimized the parameters to perform DTI at a 7 Tesla whole body MR scanner equipped with a high performance gradient system and a 32-channel head receive coil. A Stesjkal Tanner spin-echo EPI sequence was used, to acquire 110 slices with an isotropic voxel-size of 1.2 mm covering the whole brain. 60 diffusion directions were scanned which allows calculating the principal direction components of the diffusion vector in each voxel. The results prove that DTI can be performed with high quality at UHF and that it is possible to explore the SNT benefit of the higher field strength. Combining UHF fMRI data with UHF DTI results will therefore be a major step towards better neuroimaging methods.

  14. The ERK1/2 pathway participates in the upregulation of the expression of mesenteric artery α1 receptors by intravenous tail injections of mmLDL in mice.

    PubMed

    Wang, Jun-Jie; Chen, Xiao-Lan; Xu, Cang-Bao; Jiang, Gao-Feng; Lin, Jie; Liu, En-Qi; Qin, Xu-Ping; Li, Jie

    2016-02-01

    Minimally modified low density lipoprotein (mmLDL) is a risk factor for cardiovascular diseases. However, no studies examining the effect of mmLDL on vascular smooth muscle receptors have been released. The current study investigated the effect of mmLDL on the mesenteric artery α1 adrenoceptor and the molecular mechanisms. Mice were divided into the normal saline (NS), mmLDL, and mmLDL+U0126 groups. In the mmLDL+U0126 group, the animals were subjected to an intravenous tail injection of mmLDL and an intraperitoneal injection of U0126. Vascular tension caused by noradrenaline (NA) in mesenteric arteries was measured with a sensitive myograph system. The serum levels of oxLDL, TNF-α, and IL-1β were detected using enzyme-linked immunosorbent assays. The expressions of the α1 adrenoceptor, the α2 adrenoceptor, TNF-α, IL-1β, and pERK1/2 were detected using real-time polymerase chain reactions and Western blot analysis. Compared with the NS group, the mmLDL group exhibited a noticeably enhanced NA shrinkage dose-response curve and a significantly increased Emax value (P<0.01). Prazosin (α1 adrenoceptor antagonist) caused a noticeable right shift of the dose-response curve. U0126 inhibited the increases in the serum levels and vessel wall expression of IL-1β and TNF-α and enhanced the NA shrinkage dose-response curve caused by mmLDL, as observed by a significantly decreased Emax value (P<0.01). It inhibited the increased α1 adrenoceptor expression caused by mmLDL. The serum levels of IL-1β and TNF-α demonstrated a positive correlation with the NA-induced maximum shrinkage percentage. U0126 inhibited the mmLDL-induced increase in the pERK1/2 protein level in the vessel wall. In conclusion, mmLDL increased the serum levels of IL-1β and TNF-α in vivo by activating the ERK1/2 pathway, which resulted in α1 receptor-mediated vasoconstriction and an increase in the expression of α1 adrenoceptor. The results of this study may provide new ideas for the prevention

  15. Noise data from tests of a 1.83 meter (6-ft-) diameter variable-pitch 1.2-pressure-ratio fan (QF-9)

    NASA Technical Reports Server (NTRS)

    Glaser, F. W.; Wazyniak, J. A.; Friedman, R.

    1975-01-01

    Acoustic and aerodynamic data for a 1.83-meter (6-ft.) diameter fan suitable for a quiet engine for short-takeoff-and-landing (STOL) aircraft are documented. The QF-9 rotor blades had an adjustable pitch feature which provided a means for testing at several rotor blade setting angles, including one for reverse thrust. The fan stage incorporated features for low noise. Far-field noise around the fan was measured without acoustic suppression over a range of operating conditions for six different rotor blade setting angles in the forward thrust configuration, and for one in the reverse configuration. Complete results of one-third-octave band analysis of the data are presented in tabular form. Also included are power spectra, data referred to the source, and sideline perceived noise levels.

  16. Probing channel temperature profiles in Al{sub x}Ga{sub 1−x}N/GaN high electron mobility transistors on 200 mm diameter Si(111) by optical spectroscopy

    SciTech Connect

    Kyaw, L. M.; Bera, L. K.; Dolmanan, S. B.; Tan, H. R.; Bhat, T. N.; Tripathy, S.; Liu, Y.; Bera, M. K.; Singh, S. P.; Chor, E. F.

    2014-08-18

    Using micro-Raman and photoluminescence (PL) techniques, the channel temperature profile is probed in Al{sub x}Ga{sub 1-x}N/GaN high electron mobility transistors (HEMTs) fabricated on a 200 mm diameter Si(111) substrate. In particular, RuO{sub x}-based gate is used due to the semitransparent nature to the optical excitation wavelengths, thus allowing much accurate thermal investigations underneath the gate. To determine the channel temperature profile in devices subjected to different electrical bias voltages, the GaN band-edge PL peak shift calibration with respect to temperature is used. PL analyses show a maximum channel temperature up to 435 K underneath the gate edge between gate and drain, where the estimated thermal resistance in such a HEMT structure is about 13.7 KmmW{sup −1} at a power dissipation of ∼10 W/mm. The temperature profiles from micro-Raman measurements are also addressed from the E{sub 2}-high optical phonon peak shift of GaN, and this method also probes the temperature-induced peak shifts of optical phonon from Si thus showing the nature of thermal characteristics at the AlN/Si substrate interface.

  17. SU-D-19A-05: The Dosimetric Impact of Using Xoft Axxent® Electronic Brachytherapy Source TG-43 Dosimetry Parameters for Treatment with the Xoft 30 Mm Diameter Vaginal Applicator

    SciTech Connect

    Simiele, S; Micka, J; Culberson, W; DeWerd, L

    2014-06-01

    Purpose: A full TG-43 dosimetric characterization has not been performed for the Xoft Axxent ® electronic brachytherapy source (Xoft, a subsidiary of iCAD, San Jose, CA) within the Xoft 30 mm diameter vaginal applicator. Currently, dose calculations are performed using the bare-source TG-43 parameters and do not account for the presence of the applicator. This work focuses on determining the difference between the bare-source and sourcein- applicator TG-43 parameters. Both the radial dose function (RDF) and polar anisotropy function (PAF) were computationally determined for the source-in-applicator and bare-source models to determine the impact of using the bare-source dosimetry data. Methods: MCNP5 was used to model the source and the Xoft 30 mm diameter vaginal applicator. All simulations were performed using 0.84p and 0.03e cross section libraries. All models were developed based on specifications provided by Xoft. The applicator is made of a proprietary polymer material and simulations were performed using the most conservative chemical composition. An F6 collision-kerma tally was used to determine the RDF and PAF values in water at various dwell positions. The RDF values were normalized to 2.0 cm from the source to accommodate the applicator radius. Source-in-applicator results were compared with bare-source results from this work as well as published baresource results. Results: For a 0 mm source pullback distance, the updated bare-source model and source-in-applicator RDF values differ by 2% at 3 cm and 4% at 5 cm. The largest PAF disagreements were observed at the distal end of the source and applicator with up to 17% disagreement at 2 cm and 8% at 8 cm. The bare-source model had RDF values within 2.6% of the published TG-43 data and PAF results within 7.2% at 2 cm. Conclusion: Results indicate that notable differences exist between the bare-source and source-in-applicator TG-43 simulated parameters. Xoft Inc. provided partial funding for this work.

  18. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Continuum Number Counts, Resolved 1.2 mm Extragalactic Background, and Properties of the Faintest Dusty Star-forming Galaxies

    NASA Astrophysics Data System (ADS)

    Aravena, M.; Decarli, R.; Walter, F.; Da Cunha, E.; Bauer, F. E.; Carilli, C. L.; Daddi, E.; Elbaz, D.; Ivison, R. J.; Riechers, D. A.; Smail, I.; Swinbank, A. M.; Weiss, A.; Anguita, T.; Assef, R. J.; Bell, E.; Bertoldi, F.; Bacon, R.; Bouwens, R.; Cortes, P.; Cox, P.; Gónzalez-López, J.; Hodge, J.; Ibar, E.; Inami, H.; Infante, L.; Karim, A.; Le Le Fèvre, O.; Magnelli, B.; Ota, K.; Popping, G.; Sheth, K.; van der Werf, P.; Wagg, J.

    2016-12-01

    We present an analysis of a deep (1σ = 13 μJy) cosmological 1.2 mm continuum map based on ASPECS, the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field. In the 1 arcmin2 covered by ASPECS we detect nine sources at \\gt 3.5σ significance at 1.2 mm. Our ALMA-selected sample has a median redshift of z=1.6+/- 0.4, with only one galaxy detected at z > 2 within the survey area. This value is significantly lower than that found in millimeter samples selected at a higher flux density cutoff and similar frequencies. Most galaxies have specific star formation rates (SFRs) similar to that of main-sequence galaxies at the same epoch, and we find median values of stellar mass and SFRs of 4.0× {10}10 {M}⊙ and ˜ 40 {M}⊙ yr-1, respectively. Using the dust emission as a tracer for the interstellar medium (ISM) mass, we derive depletion times that are typically longer than 300 Myr, and we find molecular gas fractions ranging from ˜0.1 to 1.0. As noted by previous studies, these values are lower than those using CO-based ISM estimates by a factor of ˜2. The 1 mm number counts (corrected for fidelity and completeness) are in agreement with previous studies that were typically restricted to brighter sources. With our individual detections only, we recover 55% ± 4% of the extragalactic background light (EBL) at 1.2 mm measured by the Planck satellite, and we recover 80% ± 7% of this EBL if we include the bright end of the number counts and additional detections from stacking. The stacked contribution is dominated by galaxies at z˜ 1{--}2, with stellar masses of (1-3) × 1010 M {}⊙ . For the first time, we are able to characterize the population of galaxies that dominate the EBL at 1.2 mm.

  19. Development Of Optically-Addressed Liquid Crystal Spatial Light Modulators (OA SLM) Operating In Reflective Mode With Diameter 50 Mm Using A-Si:C:H Photoconductors And Nematic And Ferroelectric Liquid Crystals

    DTIC Science & Technology

    2005-10-17

    of the illumination intensity starts to grow again. This effect is observed for the definite range of feeding voltage frequencies. There was... irradiation of photoconductor (PC) layer the voltage, applied to it, grows in just 1-2 V. This variation of the voltage is comparable with the contact...Hence, one can provide the control over the voltage – current dependence (VCD) of irradiated PC in the range of small voltages by means of directed

  20. Comparison of retrograde intrarenal surgery versus a single-session percutaneous nephrolithotomy for lower-pole stones with a diameter of 15 to 30 mm: A propensity score-matching study

    PubMed Central

    Jung, Gyoo Hwan; Jung, Jae Hyun; Ahn, Tae Sik; Lee, Joong Sub; Cho, Sung Yong; Jeong, Chang Wook; Lee, Seung Bae; Kim, Hyeon Hoe

    2015-01-01

    Purpose To investigate surgical outcomes between retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) groups for a main stone sized 15 to 30 mm and located in the lower-pole calyx. Materials and Methods Patients who underwent PNL or RIRS for a main stone sized 15 to 30 mm and located in the lower-pole calyx were retrospectively reviewed. Each patient in the RIRS group was matched to one in the PNL group on the basis of calculated propensity scores by use of age, sex, body mass index, previous treatment history, stone site, maximum stone size, and stone volume. We compared perioperative outcomes between the unmatched and matched groups. Results Patients underwent PNL (n=87, 66.4%) or RIRS (n=44, 33.6%). After matching, 44 patients in each group were included. Mean patient age was 54.4±13.7 years. Perioperative hemoglobin drop was significantly higher and the hospital stay was longer in the PNL group than in the RIRS group. The operative time was significantly longer in the RIRS group than in the PNL group. Stone-free rates were higher and complications rates were lower in the RIRS group than in the PNL group without statistical significance. The presence of a stone located in the lower-anterior minor calyx was a predictor of stone-free status. Conclusions RIRS and single-session PNL for patients with a main stone of 15 to 30 mm located in the lower-pole calyx showed comparable surgical results. However, RIRS can be performed more safely than PNL with less bleeding. Stones in the lower-anterior minor calyx should be carefully removed during these procedures. PMID:26175872

  1. Directional Solidification and Convection in Small Diameter Crucibles

    NASA Technical Reports Server (NTRS)

    Chen, J.; Sung, P. K.; Tewari, S. N.; Poirier, D. R.; DeGroh, H. C., III

    2003-01-01

    Pb-2.2 wt% Sb alloy was directionally solidified in 1, 2, 3 and 7 mm diameter crucibles. Pb-Sb alloy presents a solutally unstable case. Under plane-front conditions, the resulting macrosegregation along the solidified length indicates that convection persists even in the 1 mm diameter crucible. Al-2 wt% Cu alloy was directionally solidified because this alloy was expected to be stable with respect to convection. Nevertheless, the resulting macrosegregation pattern and the microstructure in solidified examples indicated the presence of convection. Simulations performed for both alloys show that convection persists for crucibles as small as 0.6 mm of diameter. For the solutally stable alloy, Al-2 wt% Cu, the simulations indicate that the convection arises from a lateral temperature gradient.

  2. Finite Element Analysis of Bone Stress around Micro-Implants of Different Diameters and Lengths with Application of a Single or Composite Torque Force

    PubMed Central

    Lu, Ying-juan; Chang, Shao-hai; Ye, Jian-tao; Ye, Yu-shan; Yu, Yan-song

    2015-01-01

    Background Stress on the bone surrounding dental micro-implants affects implant success. Purpose To compare the stress on the bone surrounding a micro-implant after application of a single force (SF) of 200 g or a composite force (CF) of 200 g and 6 N.mm torque. Materials and Methods Finite element models were developed for micro-implant diameters of 1.2, 1.6, and 2.0 mm, and lengths of 6, 8, 10, and 12 mm and either a SF or CF was applied. The maximum equivalent stress (Max EQS) of the bone surrounding the micro-implant was determined, and the relationships among type of force, diameter, and length were evaluated. Results The Max EQS of the CF exceeded that of the SF (P< 0.05). The effect of force on stress was related to implant diameter, but not to implant length. The larger CF led to greater instability of the micro-implant and the effect was most pronounced at an implant diameter of 1.2 mm. The use of implant diameters of 1.6 mm and 2.0 mm produced no significant difference in implant stability when either a CF or SF was applied. Conclusion When considering the use of an implant to perform three-dimensional control on the teeth, the implant diameter chosen should be > 1.2 mm. PMID:26659581

  3. The effect of initial diameter in sperically symmetric droplet combustion of sooting fuels

    NASA Technical Reports Server (NTRS)

    Jackson, G. S.; Avedisian, C. T.

    1994-01-01

    The effect of initial droplet diameter on the burning rate of sooting fuels - n-heptane and 1-chloro-octane - was examined experimentally at low gravity. A 1.2s drop tower provided a low gravity environment to minimize buoyancy and achieve spherically symmetric flames for stationary droplets. Free-floating and fiber-supported droplets were burned, and both techniques gave matching results for droplets of similar initial diameter. Burning rate constants for both fuels were measured for a large number of droplets ranging from 0.4 to 1.1mm in initial diameter.

  4. Apollo 17 Index: 70 mm, 35 mm, and 16 mm Photographs

    NASA Technical Reports Server (NTRS)

    Wells, Ronald A. (Compiler)

    1974-01-01

    This index lists and provides supplemental data for all Apollo 17 70 mm, 35 mm, and 16 mm photographs. The 70 mm and 35 mm photographs are indexed in three ways: (1) all photographs are listed in numerical sequence according to NASA photograph number, (2) photographs exposed in lunar orbit are listed according to longitude in 10deg increments, and (3) all photographs exposed on the lunar surface are listed in chronological order. In indexing the 70 mm and 35 mm orbital photographs, individual frames were matched to imagery on the 1:2,750,000 scale Lunar Planning Charts (LOC). Each frame was outlined on the LOC base map, and the principal point determined. The latitude and longitude of each principal point, to the nearest 0.1 degree, is recorded in this index, If the principal point of a photograph is in space or its location obscured by shadow, an approximate longitude was recorded so that the photograph would not be excluded from the computer-generated listing by longitude. Each frame is described in terms of a named lunar surface feature within the boundaries of the frame or, if no named features are within the frame boundaries, a major nearby feature.

  5. Effect of Crucible Diameter Reduction on the Convection, Macrosegregation, and Dendritic Morphology during Directional Solidification of Pb-2.2 Wt Pct Sb Alloy

    NASA Technical Reports Server (NTRS)

    Chen, Jun; Tewari, S. N.; Magadi, G.; DeGroh, H. C., III

    2003-01-01

    The Pb-2.2 wt pct Sb alloy has been directionally solidified in 1-, 2-, 3-, and 7-mm-diameter crucibles with planar and dendritic liquid-solid interface orphology. For plane front solidification, the experimentally observed macrosegregation along the solidified length follows the relationship proposed by Favier. Application of a 0.4 T transverse magnetic field has no effect on the extent of convection. Reducing the ampoule diameter appears to decrease the extent of convection. However, extensive convection is still present even in the 1-mm-diameter crucible. An extrapolation of the observed behavior indicated that nearly diffusive transport conditions require ampoules that are about 40 microns in diameter. Reduction of the crucible diameter does not appear to have any significant effect on the primary dendrite spacing. However, it results in considerable distortion of the dendrite morphology and ordering. This is especially true for the 1-mm diameter samples.

  6. Analysis on the stress of the bone surrounding mini-implant with different diameters and lengths under torque.

    PubMed

    Lu, Yingjuan; Chang, Shaohai; Ye, Jiantao; Ye, Yushan; Yu, Yansong

    2015-01-01

    The purpose of this study is to compare the stress of the bone around the mini-implant under the two kinds of force: the composite force which contains torque and traditional single force. There were 96 finite element models formed by the combination of mini-implant and bone, with diameters of 1.2 mm, 1.6 mm, 2.0 mm and corresponding length being 6 mm, 8 mm, 10 mm, 12 mm, respectively. Each size corresponded to 8 models. Group SF (each size n=4) was loaded with 200 g single force, while Group CF (each size n=4) was loaded with composite force which contained 6N mm torque and 200 g single force. The maximum equivalent stress (Max EQS) of the bone surrounding mini implant with different loading directions was calculated, and the relationship of force direction, diameter and length was also evaluated. The Max EQS of Group CF was higher than that of Group SF. The effect of force direction on the stress was related to the diameter of mini implant, but had nothing to do with its length. The Max EQS of the cortical bone around mini implant in Group CF was higher (P<0.05) than that in Group SF. In contrast, there was no significant difference (P>0.05) between Group SF and Group CF in terms of bone stress when the diameter of mini implant was 1.6 mm or 2.0 mm. In our study, it is demonstrated that the diameter of mini-implant is better to be larger than 1.2 mm when a mini-implant is used in a torque control of tooth. The impact of this feature in the clinical setting needs to be verified.

  7. Room-temperature 1.2-J Fe{sup 2+}:ZnSe laser

    SciTech Connect

    Velikanov, S D; Zaretsky, N A; Zotov, E A; Maneshkin, A A; Yutkin, I M; Kazantsev, S Yu; Kononov, I G; Firsov, K N; Korostelin, Yu V; Frolov, M P

    2016-01-31

    The characteristics of a laser based on a Fe{sup 2+}:ZnSe single crystal pumped by an electric-discharge HF laser at room temperature are studied. The HF laser beam diameter on the crystal surface was 17 mm. The achieved laser energy was 1.2 J with an efficiency of ∼ 25% with respect to the pump energy. (letters)

  8. Anatomical evaluation of the root canal diameter and root thickness on the apical third of mesial roots of molars.

    PubMed

    Martos, Josué; Tatsch, Gustavo Henrique; Tatsch, Augusto César; Silveira, Luiz Fernando Machado; Ferrer-Luque, Carmen María

    2011-09-01

    The purpose was to determine the diameter of the main root canal and wall thickness in the apical dentin in mesial roots of maxillary and mandibular molars. Forty mesiobuccal and mesial root specimens were sectioned horizontally at 1, 2 and 3 mm from the apex, and measured at each top surface by using optical microscopy to an accuracy of ×20 magnification. The anatomical parameters were established as the following points of reference: AB, two points connected by a line from the outer edge of the mesial wall to the outer edge of the distal one through the center of the root canal to measure the thickness of the root and mesiodistal diameter of the root canal (CD). A second line (EF) was designed to evaluate the diameter of the root canal in the buccolingual direction. All data were summarized, and values were assessed statistically by ANOVA and Bonferroni multiple comparisons. The buccolingual (BL) root canal diameters at 1, 2 and 3 mm in the mandibular and maxillary molars were greater than in the mesiodistal (MD), showing statistically significant differences (p < 0.05). The MD root thicknesses at 1, 2 and 3 mm in mandibular and maxillary molars were statistically significant (p < 0.05). The lowest value to 1 mm from the apex in the mandibular molars was 1.219 mm and the highest at 3 mm from the root apex in maxillary molars was 1.741 mm. The BL diameters in maxillary and mandibular molars were higher than the MD diameter. The thickness (MD) of maxillary and mandibular molars decreased as a function of apical proximity.

  9. Interpreting stem diameter changes

    NASA Astrophysics Data System (ADS)

    Hölttä, T.; Sevanto, S.; Nikinmaa, E.

    2009-12-01

    Detecting phloem transport in stem diameter changes Teemu Hölttä1, Sanna Sevanto2, Eero Nikinmaa1 1Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland 2Department of Physics, P.O. Box 48, FIN-00014 University of Helsinki, Finland Introduction The volume of living cells and xylem conduits vary according to pressures they are subjected to. Our proposition is that the behavior of the inner bark diameter variation which cannot be explained by changes in xylem water status arise from changes in the osmotic concentration of the phloem and cambial growth. Materials and methods Simultaneous xylem and stem diameter measurements were conducted between June 28th to October 4th 2006 in Southern Finland on a 47-year old, 15 meter tall, Scots pine tree (DBH 15 cm) at heights of 1.5 and 10 meters. The difference between the measured inner bark diameter and the inner bark diameter predicted from xylem diameter change with a simple model (assuming there was no change in the osmotic concentration of the phloem) is hypothesized to give the changes in the osmotic concentration of the inner bark. The simple model calculates the radial water exchange between the xylem and phloem driven by the water potential changes in the xylem. Results and Discussion The major signal in the inner bark diameter was the transpiration rate as assumed, but also a signal arising from the change in the osmotic concentration (Fig 1a). The predicted osmotic concentration of the phloem typically increased during the afternoon due to the loading of photosynthesized sugars to the phloem. Inner bark osmotic concentration followed the photosynthesis rate with a 3 and 4 hour time-lag at the top and base, respectively (Fig 1b). The connection between photosynthesis and the predicted change in phloem osmotic concentration was stronger in the upper part of the tree compared to lower part. The changes in the predicted osmotic concentration were not similar every day, indicating that

  10. Precision wire feeder for small diameter wire

    DOEpatents

    Brandon, E.D.; Hooper, F.M.; Reichenbach, M.L.

    1992-08-11

    A device for feeding small diameter wire having a diameter less than 0.04 mm (16 mil) to a welding station includes a driving wheel for controllably applying a non-deforming driving force to the wire to move the free end of the wire towards the welding station; and a tension device such as a torque motor for constantly applying a reverse force to the wire in opposition to the driving force to keep the wire taut. 1 figure.

  11. Precision wire feeder for small diameter wire

    DOEpatents

    Brandon, Eldon D.; Hooper, Frederick M.; Reichenbach, Marvin L.

    1992-01-01

    A device for feeding small diameter wire having a diameter less than 0.04 mm (16 mil) to a welding station includes a driving wheel for controllably applying a non-deforming driving force to the wire to move the free end of the wire towards the welding station; and a tension device such as a torque motor for constantly applying a reverse force to the wire in opposition to the driving force to keep the wire taut.

  12. A comparison of the heat transfer and pressure drop performance of R-134a-lubricant mixtures in different diameter smooth tubes and micro-fin tubes

    SciTech Connect

    Eckels, S.J.; Doerr, T.M.; Pate, M.B.

    1998-10-01

    The average heat transfer coefficients and pressure drops during evaporation and condensation are reported for mixtures of R-134a and an ester lubricant in tubes of 12.7 mm (1/2 in.) outer diameter. The objective of this paper is to evaluate the performance of the R-134a-lubricant mixtures in these tubes and determine the performance benefits of the micro-fin tube. The performance benefits of the tubes with 12.7 mm (1/2 in.) outer diameter are compared to those of smaller tubes with 9.52 mm (3/8 in.) outer diameter. The lubricant used was a 169 SUS penta erythritol ester mixed-acid lubricant. The lubricant concentration was varied from 0--5.1% in the mixture. The average heat transfer coefficients in the 12.7 mm (1/2 in.) micro-fin tube were 50--150% higher than those for the 12.7 mm (1/2 in.) smooth tube, while pressure drops in the micro-fin tube were 5% to 50% higher than in the smooth tube. The addition of lubricant degraded the average heat transfer coefficients in all cases except during evaporation at low lubricant concentrations. Pressure drops were always increased with the addition of lubricant. The experimental results also indicate that tube diameter has some effect on the performance benefits of the micro-fin tube over that of the smooth tube.

  13. Dynamic contrast-enhanced susceptibility-weighted perfusion MRI (DSC-MRI) in a glioma model of the rat brain using a conventional receive-only surface coil with a inner diameter of 47 mm at a clinical 1.5 T scanner.

    PubMed

    Ulmer, Stephan; Reeh, Matthias; Krause, Joerg; Herdegen, Thomas; Heldt-Feindt, Janka; Jansen, Olav; Rohr, Axel

    2008-07-30

    Magnetic resonance (MR) imaging in animal models is usually performed in expensive dedicated small bore animal scanners of limited availability. In the present study a standard clinical 1.5 T MR scanner was used for morphometric and dynamic contrast-enhanced susceptibility-weighted MR imaging (DSC-MRI) of a glioma model of the rat brain. Ten male Wistar rats were examined with coronal T2-weighted, and T1-weighted images (matrix 128 x 128, FOV 64 mm) after implantation of an intracerebral tumor xenografts (C6) using a conventional surface coil. For DSC-MRI a T2*-weighted sequence (TR/TE=30/14 ms, matrix 64 x 64, FOV 90 mm; slice thickness of 1.5mm) was performed. Regions of interest were defined within the tumor and the non-affected contralateral hemisphere and the mean transit time (MTT) was determined. Tumor dimensions in MR predicted well its real size as proven by histology. The MTT of contrast agent passing through the brain was significantly decelerated in the tumor compared to the unaffected hemisphere (p<0.001, paired t-test), which is most likely due to the leakage of contrast agent through the disrupted blood brain barrier. This setup offers advanced MR imaging of small animals without the need for dedicated animal scanners or dedicated custom-made coils.

  14. Solar Diameter Latitude Dependence

    NASA Astrophysics Data System (ADS)

    Emilio, M.; Leister, N. V.; Laclare, F.

    The observing programs of the Sun for determining the fundamental system of reference enable, as a by-product, to measure the apparent solar diameter (Poppe, P.C.R. et al. 1996; Leister et al. 1996; Laclare et al. 1991). The diameter obtained at the Calern Observatory (φ = 43-circ 44' 55''.9; λ = -0h 27m 42s.44) and at Abrahao de Moraes Observatory (OAM) (φ = -23-circ 00'6''.0; λ = 3h 07m 52s.22) was analyzed searching for periodicity evidences. For this we utilized the temporal methods CLEAN and CLEANEST. The analysis in function of heliographic latitude shows a dependence that may be correlated to mode of pulsation non-radial gravity. A discussion is made in terms of physical parameters like temperature luminosity and magnetic field involving the solar radius (Emilio M. 1997; Laclare et al. 1996).

  15. Double diameter boring tool

    DOEpatents

    Ashbaugh, Fred N.; Murry, Kenneth R.

    1988-12-27

    A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

  16. Double diameter boring tool

    DOEpatents

    Ashbaugh, F.A.; Murry, K.R.

    1986-02-10

    A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting flutes formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first flute tip to the axis of rotation plus the distance from the second flute tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second flute tip to the axis of rotation minus one-half the distance from the first flute tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

  17. The Energy Diameter Effect

    SciTech Connect

    Souers, P; Vitello, P; Garza, R; Hernandez, A

    2007-04-20

    Various relations for the detonation energy and velocity as they relate to the inverse radius of the cylinder are explored. The detonation rate-inverse slope relation seen in reactive flow models can be used to derive the familiar Eyring equation. Generalized inverse radii can be shown to fit large quantities of cylinder and sphere results. A rough relation between detonation energy and detonation velocity is found from collected JWL values. Cylinder test data for ammonium nitrate mixes down to 6.35 mm radii are presented, and a size energy effect is shown to exist in the Cylinder test data. The relation that detonation energy is roughly proportional to the square of the detonation velocity is shown by data and calculation.

  18. The Energy Diameter Effect

    SciTech Connect

    Vitello, P; Garza, R; Hernandez, A; Souers, P C

    2007-07-10

    We explore various relations for the detonation energy and velocity as they relate to the inverse radius of the cylinder. The detonation rate-inverse slope relation seen in reactive flow models can be used to derive the familiar Eyring equation. Generalized inverse radii can be shown to fit large quantities of cylinder results. A rough relation between detonation energy and detonation velocity is found from collected JWL values. Cylinder test data for ammonium nitrate mixes down to 6.35 mm radii are presented, and a size energy effect is shown to exist in the Cylinder test data. The relation that detonation energy is roughly proportional to the square of the detonation velocity is shown by data and calculation.

  19. Reconstruction of small diameter arteries using decellularized vascular scaffolds.

    PubMed

    Nagaoka, Yuki; Yamada, Hiroshi; Kimura, Tsuyoshi; Kishida, Akio; Fujisato, Toshia; Takakuda, Kazuo

    2014-03-19

    Although artificial vessels are available for large diameter arteries, there are no artificial vessels for small diameter arteries of < 4 mm. We created a decellularized vascular scaffold (length, 10 mm; outer diameter, 1.5 mm; inner diameter, 1.3 mm) from rat abdominal arteries. We measured the biomechanical characteristics of the scaffolds, implanted them to defects made in rat carotid arteries, and evaluated their patency and the endothelial cell linings. Silastic grafts were implanted as controls. The decellularized scaffolds demonstrated similar mechanical characteristics to normal arteries. All of the control grafts were occluded. Fibroblast-like cells were discovered in the thrombus, and fibrous organization was apparent. In contrast, patency of the grafts in 10 of 12 animals was observed 4 weeks after implantation. The internal cavity of the patent scaffold was completely lined by endotheliallike cells. Thus, the possibility of small artery reconstruction using decellularized scaffolds was demonstrated.

  20. The DIAMET campaign

    NASA Astrophysics Data System (ADS)

    Vaughan, G.

    2012-04-01

    DIAMET (DIAbatic influences on Mesoscale structures in ExTratropical storms) is a joint project between the UK academic community and the Met Office. Its focus is on understanding and predicting mesoscale structures in synoptic-scale storms, and in particular on the role of diabatic processes in generating and maintaining them. Such structures include fronts, rain bands, secondary cyclones, sting jets etc, and are important because much of the extreme weather we experience (e.g. strong winds, heavy rain) comes from such regions. The project conducted two field campaigns in the autumn of 2011, from September 14 - 30 and November 24 - December 14, based around the FAAM BAe146 aircraft with support from ground-based radar and radiosonde measurements. Detailed modelling, mainly using the Met Office Unified model, supported the planning and interpretation of these campaigns. This presentation will give a brief overview of the campaigns. Both in September and November-December the weather regime was westerly, with a strong jet stream directed across the Atlantic. Three IOPs were conducted in September, to observe a convective band ahead of an upper-level trough, waves on a long trailing cold front, and a warm conveyor belt associated with a secondary cyclone. In November-December six IOPs were conducted, to observe frontal passages and high winds. This period was notable for a number of very strong windstorms passing across the north of the UK, and gave us an opportunity to examine bent-back warm fronts in the southern quadrant of these storms where the strongest winds are found. The case studies fell into two basic patterns. In the majority of cases, dropsonde legs at high level were used to obtain a cross-section of winds and thermodynamic structure (e.g. across a front), followed by in situ legs at lower levels (generally where the temperature was between 0 and -10°) to examine microphysical processes, especially ice multiplication and the extent of supercooled water

  1. Primeval galaxies in the sub-mm and mm

    NASA Technical Reports Server (NTRS)

    Bond, J. Richard; Myers, Steven T.

    1993-01-01

    Although the results of COBE's FIRAS experiment 1 constrain the deviation in energy from the CMB blackbody in the 500-5000 micron range to be delta E/E, sub cmb less than 0.005, primeval galaxies can still lead to a brilliant sub-mm sky of non-Gaussian sources that are detectable at 10 inch resolution from planned arrays such as SCUBA on the James Clerk Maxwell Telescope and, quite plausibly, at sub-arcsecond resolution in planned mm and sub-mm interferometers. Here, we apply our hierarchical peaks method to a CDM model to construct sub-mm and mm maps of bursting PG's appropriate for these instruments with minimum contours chosen to correspond to realistic observational parameters for them and which pass the FIRAS limits.

  2. Architectural Analyses and Developments of 1 mm Diameter Micro Forceps for Catheter Surgery

    NASA Astrophysics Data System (ADS)

    Nokata, Makoto; Hashimoto, Yusuke; Obayashi, Takumi

    Blockage in a blood vessel due to cardiovascular disease such as arteriosclerosis or aneurysms requires minimally invasive placement of a mesh tube or platinum coil stent via a catheter to open the affected area. Stents are positioned using a guide wire via a catheter, but the stent may be dropped on the way to its destination and requires much time in surgery, increasing the burden on the patient. Medical apparatuses are thus desired having a mechanism to grasp artifacts securely in blood vessels. We designed prototype microforceps for use on the end of a catheter for grasping operation in blood vessels and to contribute to medical apparatuses in this field. The microforceps we designed using a minimum number of parts uses metal injection molding (MIM) to realize strong mass production. Microforceps installed in the tip of a catheter. Stress analysis verified its capability to grasp, bend and turn within the confines of a blood vessels model.

  3. Pulling of 3 mm diameter AlSb rods by micro-pulling down method

    SciTech Connect

    Bourret-Courchesne Ph.D., Edith; Perrodin, Didier

    2009-05-14

    We designed and supplied special crucibles for AlSb material. Thermal insulation and limitation of Sb losses were our first work. The protection of the growth environment was also one of our priority to avoid any pollution of the Fibercryst {mu}PD facility. When this work was achieved, the next step was the calibration of the heating power for these new crucibles. Then, it was the definition of single crystal growth conditions that oriented our research. Following our proposal, many growths attempts were performed. We started from Al & Sb pure powder or from LBNL AlSb crystal as expected. We used different crucibles and different seeds.

  4. Laser amplifier based on a neodymium glass rod 150 mm in diameter

    SciTech Connect

    Shaykin, A A; Fokin, A P; Soloviev, A A; Kuzmin, A A; Shaikin, I A; Burdonov, K F; Khazanov, E A; Charukhchev, A V

    2014-05-30

    A unique large-aperture neodymium glass rod amplifier is experimentally studied. The small-signal gain distribution is measured at different pump energies. The aperture-averaged gain is found to be 2.3. The stored energy (500 J), the maximum possible pump pulse repetition rate, and the depolarisation in a single pulse and in a series of pulses with a repetition rate of one pulse per five minutes are calculated based on the investigations performed. It is shown that the use of this amplifier at the exit of the existing laser can increase the output pulse energy from 300 to 600 J. (lasers)

  5. Wheel Diameter and Speedometer Reading

    ERIC Educational Resources Information Center

    Murray, Clifton

    2010-01-01

    Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it…

  6. Five meter diameter conical furlable antenna

    NASA Technical Reports Server (NTRS)

    Fortenberry, J. W.; Freeland, R. E.; Moore, D. M.

    1976-01-01

    An investigation was made to demonstrate that a 5-meter-diameter, furlable, conical reflector antenna utilizing a line source feed can be fabricated utilizing composite materials and to prove that the antenna can function mechanically and electrically as prototype flight hardware. The design, analysis, and testing of the antenna are described. An RF efficiency of 55% at 8.5 GHz and a surface error of 0.64 mm rms were chosen as basic design requirements. Actual test measurements yielded an efficiency of 53% (49.77 dB gain) and a surface error of 0.61 mm rms. Atmospherically induced corrosion of the reflector mesh resulted in the RF performance degradation. An assessment of the antenna as compared to the current state of the art technology was made. This assessment included cost, surface accuracy and RF performance, structural and mechanical characteristics, and possible applications.

  7. Fiber diameter control in electrospinning

    NASA Astrophysics Data System (ADS)

    Stepanyan, R.; Subbotin, A.; Cuperus, L.; Boonen, P.; Dorschu, M.; Oosterlinck, F.; Bulters, M.

    2014-10-01

    A simple model is proposed to predict the fiber diameter in electrospinning. We show that the terminal diameter is determined by the kinetics of the jet elongation—under the influence of the electric and viscous forces—and the solvent evaporation. Numerical and simple scaling analyses are performed, predicting the fiber diameter to scale as a power 1/3 of viscosity and 2/3 of polymer solution throughput divided by electrical current. Model predictions show a good agreement to our own electrospinning experiments on polyamide-6 solutions as well as to the data available in the literature.

  8. 77 FR 59374 - Certain Small Diameter Carbon and Alloy Seamless Standard, Line and Pressure Pipe (Under 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-27

    ...] Certain Small Diameter Carbon and Alloy Seamless Standard, Line and Pressure Pipe (Under 4\\1/2\\ Inches... and pressure pipe (under 4\\1/2\\ inches) (hereinafter, ``small diameter pipe'') from Japan for...

  9. Crystal Growth and Electrical Properties of Lead-Free Piezoelectric Material (Na1/2Bi1/2)TiO3-BaTiO3

    NASA Astrophysics Data System (ADS)

    Hosono, Yasuharu; Harada, Kouichi; Yamashita, Yohachi

    2001-09-01

    Single crystals of lead-free piezoelectric material x(Na1/2Bi1/2)TiO3-yBaTiO3 (NBBT 100x/100y) have been successfully grown by the flux method and the Bridgman method. Using the flux method, crystals having an edge length of 2-8 mm were obtained using Bi2O3 flux with cooling from 1350°C to 800°C at a rate of 3.5°C/h. Using the Bridgman method, comparatively good crystal of 15 mm diameter and 50 mm length was obtained using Bi2O3 flux with the Pt crucible driven down through the heat zone at a speed of 1.0 mm/h. The resulting crystals showed single-phase perovskite structure. Inductively charged plasma (ICP) chemical analysis revealed that the composition of the pulverized powder of these crystals is NBBT 97/3, which is slightly different from the charged composition of NBBT 94/6. One of the single crystals grown by the Bridgman method showed a dielectric constant of 1230 at room temperature and a dielectric constant peak at 313°C.

  10. The Table Mountain 8-mm wavelength interferometer

    NASA Technical Reports Server (NTRS)

    Janssen, M. A.; Gary, B. L.; Gulkis, S.; Olsen, E. T.; Soltis, F. S.; Yamane, N. I.

    1979-01-01

    A two-element radio interferometer operating at 8.33-mm wavelength has been developed at the Jet Propulsion Laboratory's Table Mountain Observatory near Wrightwood, CA. The interferometer employs a 5.5-m and a 3-m diameter antenna on an east-west baseline of 60 or 120 m, yielding fringe spacings at transit of 28 or 14 arcsec, respectively. The broad intermediate-frequency bandpass of 100-350 MHz and the system noise temperature of 500 K provide high sensitivity for the measurement of continuum sources. The interferometer has been used for high-resolution studies of the planets and the sun, and it is currently being adapted to study solar flare emissions at high spatial and time resolution.

  11. Wheel Diameter and Speedometer Reading

    NASA Astrophysics Data System (ADS)

    Murray, Clifton

    2010-09-01

    Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it makes a good illustration of how reasoning in physics can lead to a result that is useful outside the classroom.

  12. The philosophies of dowel diameter preparation: a literature review.

    PubMed

    Lloyd, P M; Palik, J F

    1993-01-01

    This article reviewed the literature regarding the diameter of dowels and identified three distinct philosophies of dowel space preparation. One group advocated the narrowest diameter for fabrication of a dowel to a desired length. Another recommended a dowel space with an apical diameter equal to one third of the narrowest dimension of the root at the terminus of the dowel. A third group advised that at least 1 mm of sound dentin should surround the entire surface of the dowel. A combination of the one third and 1 mm minimal philosophies yielded a practical guideline for dowel space preparation, particularly in aged teeth. Requiring a definite amount of tooth structure surrounding the dowel, while adhering to the one third proportion, indicated upper limits on both the diameter and length of the dowel. These calculated limits served as convenient starting points in selecting a specific style of dowel and assisted in determining whether additional measures are warranted to enhance dowel retention.

  13. 1,2-Diphenylhydrazine

    Integrated Risk Information System (IRIS)

    1,2 - Diphenylhydrazine ; CASRN 122 - 66 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  14. 1,2-Dibromoethane

    Integrated Risk Information System (IRIS)

    EPA 635 / R - 04 / 067 www.epa.gov / iris TOXICOLOGICAL REVIEW OF 1,2 - DIBROMOETHANE ( CAS No . 106 - 93 - 4 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) June 2004 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been revie

  15. 1,2-Dichloropropane

    Integrated Risk Information System (IRIS)

    1,2 - Dichloropropane ; CASRN 78 - 87 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  16. 1,2-Dichlorobenzene

    Integrated Risk Information System (IRIS)

    1,2 - Dichlorobenzene ; CASRN 95 - 50 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  17. 1,2-Dichloroethane

    Integrated Risk Information System (IRIS)

    1,2 - Dichloroethane ; CASRN 107 - 06 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  18. Apollo 12 photography 70 mm, 16 mm, and 35 mm frame index

    NASA Technical Reports Server (NTRS)

    1970-01-01

    For each 70-mm frame, the index presents information on: (1) the focal length of the camera, (2) the photo scale at the principal point of the frame, (3) the selenographic coordinates at the principal point of the frame, (4) the percentage of forward overlap of the frame, (5) the sun angle (medium, low, high), (6) the quality of the photography, (7) the approximate tilt (minimum and maximum) of the camera, and (8) the direction of tilt. A brief description of each frame is also included. The index to the 16-mm sequence photography includes information concerning the approximate surface coverage of the photographic sequence and a brief description of the principal features shown. A column of remarks is included to indicate: (1) if the sequence is plotted on the photographic index map and (2) the quality of the photography. The pictures taken using the lunar surface closeup stereoscopic camera (35 mm) are also described in this same index format.

  19. Stellar diameters and temperatures. IV. Predicting stellar angular diameters

    SciTech Connect

    Boyajian, Tabetha S.; Van Belle, Gerard; Von Braun, Kaspar

    2014-03-01

    The number of stellar angular diameter measurements has greatly increased over the past few years due to innovations and developments in the field of long baseline optical interferometry. We use a collection of high-precision angular diameter measurements for nearby, main-sequence stars to develop empirical relations that allow the prediction of stellar angular sizes as a function of observed photometric color. These relations are presented for a combination of 48 broadband color indices. We empirically show for the first time a dependence on metallicity of these relations using Johnson (B – V) and Sloan (g – r) colors. Our relations are capable of predicting diameters with a random error of less than 5% and represent the most robust and empirical determinations of stellar angular sizes to date.

  20. Feasibility of a Sustainer Projectile in the 30-mm, 35-mm, and 40-mm Caliber Range

    DTIC Science & Technology

    1980-08-01

    calibers appropriate for air defense. Sustaining the muzzle velocity has the advantage of decreasing the projectile time of flight, thus reducing the...mm Rocket-Assisted Projectiles Air Defense 30 mm 20 A@SrACT I"Centfate an eerseod if VHW en Identify by blocek number) A sustainer projectile is a...feasibility of RAP’s in the smaller calibers appropriate for air defense, * .i.e., the 30-40 nn caliber range. The nominal objective of this study was to

  1. Three-dimensional finite element analysis of stress distribution in a tooth restored with metal and fiber posts of varying diameters: An in-vitro study

    PubMed Central

    Kumar, Pradeep; Rao, R. Nageswar

    2015-01-01

    Objective: To compare stress distribution in a tooth restored with metal and fiber posts of varying diameters (1.2 and 1.4 mm) by means of three-dimensional finite element analysis (3D-FEA). Materials and Methods: Four 3D-FEA models were constructed: (1) fiber post (1.2 and 1.4 mm) and (2) metal post (1.2 and 1.4 mm). The material properties were assigned and a force of 100 N was applied at 45° angle to the longitudinal axis of the tooth onto the palatal surface incisal to the cingulum. Analysis was run and stress distribution pattern was studied. Results: Maximum stresses in the radicular tooth structure for fiber post were higher than that for metal post. In the former models, stresses in the tooth structure were slightly reduced with increase in fiber post diameter. Conclusions: To reduce stress in the remaining radicular tooth structure, it is better to use a fiber post of a large diameter. PMID:25829685

  2. Large-diameter glory-hole drilling: Evolution from 12- to 20-ft diameter

    SciTech Connect

    Shields, R.

    1994-06-01

    To drill for oil and gas in shallow, ice-infested waters, a hole needs to be excavated in the seafloor to protect subsea blowout preventers (BOP's) from ice-scour damage. Canadian Marine Drilling pioneered the use of large-diameter glory-hole drilling systems by designing, building, and patenting a 12-ft (3.7-m)-diameter prototype bit system, a 17-ft (5.2-m)-diameter upgrade, a 20-ft (6.1-m)-diameter standard system, and a 20-ft (6.1-m)-diameter enhanced system. The enhanced bit design incorporates high-pressure jetting, boulder storage, pilot-hole centering, and other features that allow a 36-in (0.91-m) hole to be drilled through the body of the bit. An optional feature is the ability to drill and case the glory hole simultaneously. To date, penetration rates up to 4.5 ft/hr (1.37 m/h) in soils with a shear strength 5,000 lbf/ft[sup 2] (239 kPa) have been obtained. Glory-hole drilling times have been reduced from more than 20 days in 1978 to approximately 1[1/2] days since 1986.

  3. Regulation of electrospun scaffold stiffness via coaxial core diameter.

    PubMed

    Drexler, J W; Powell, H M

    2011-03-01

    Scaffold mechanics influence cellular behavior, including migration, phenotype and viability. Scaffold stiffness is commonly modulated through cross-linking, polymer density, or bioactive coatings on stiff substrates. These approaches provide useful information about cellular response to substrate stiffness; however, they are not ideal as the processing can change substrate morphology, density or chemistry. Coaxial electrospinning was investigated as a fabrication method to produce scaffolds with tunable stiffness and strength without changing architecture or surface chemistry. Core solution concentration, solvent and feed rate were utilized to control core diameter with higher solution concentration and feed rate positively correlating with increased fiber diameter and stiffness. Coaxial scaffolds electrospun with an 8 wt./vol.% polycaprolactone (PCL)-HFP solution at 1 ml h(-1) formed scaffolds with an average core diameter of 1.1±0.2 μm and stiffness of 0.027±3.3×10(-3) N mm(-1). In contrast, fibers which were 2.6±0.1 μm in core diameter yielded scaffolds with a stiffness of 0.065±4.7×10(-3) N mm(-1). Strength and stiffness positively correlated with core diameter with no significant difference in total fiber diameter and interfiber distance observed in as-spun scaffolds. These data indicate that coaxial core diameter can be utilized to tailor mechanical properties of three-dimensional scaffolds and would provide an ideal scaffold for assessing the effect of scaffold mechanics on cell behavior.

  4. High voltage variable diameter insulator

    DOEpatents

    Vanacek, D.L.; Pike, C.D.

    1982-07-13

    A high voltage feedthrough assembly having a tubular insulator extending between the ground plane ring and the high voltage ring. The insulator is made of Pyrex and decreases in diameter from the ground plane ring to the high voltage ring, producing equipotential lines almost perpendicular to the wall of the insulator to optimize the voltage-holding capability of the feedthrough assembly.

  5. Large-diameter astromast development

    NASA Technical Reports Server (NTRS)

    Finley, L. A.

    1984-01-01

    The 15-m-long by 0.75-diameter deployable supermast was delivered. The performance characteristics, design parameters, and developmental work associated with this mast are described. The main differences, besides the length of these two mast sections, are a change in the longeron material (the principal structural member) to a circular cross section and the incorporation of a lanyard-bridle system which makes unaided deployment and retraction possible in zero gravity.

  6. High voltage variable diameter insulator

    DOEpatents

    Vanecek, David L.; Pike, Chester D.

    1984-01-01

    A high voltage feedthrough assembly (10) having a tubular insulator (15) extending between the ground plane ring (16) and the high voltage ring (30). The insulator (15) is made of Pyrex and decreases in diameter from the ground plane ring (16) to the high voltage ring (30), producing equipotential lines almost perpendicular to the wall (27) of the insulator (15) to optimize the voltage-holding capability of the feedthrough assembly (10).

  7. Novel Processing of 81-mm Cu Shaped Charge Liners

    SciTech Connect

    Schwartz, A; Korzekwa, D

    2002-01-16

    A seven-step procedure was developed for producing shaped charge liner blanks by back extrusion at liquid nitrogen temperatures. Starting with a 38.1-mm diameter, 101.6-mm long cylinder at 77K, three forging steps with a flat-top die are required to produce the solid cone while maintaining low temperature. The solid cone is forged in four individual back extrusions at 77K to produce the rough liner blank. This procedure is capable of being run in batch processes to improve the time efficiency.

  8. Stemming selection for large-diameter blastholes

    SciTech Connect

    Eloranta, J.

    1994-12-31

    Proper selection of stemming has a profound effect on blast performance. This paper describes several methods of evaluating stemming performance in 16-inch blastholes. Tests are done on stemming ranging in size from nominal 1/4 inch crushed rock up to railroad ballast size rock (2 1/2 inch > diameter < 3/4 inch). Concrete plugs (both pre-cast and poured) are evaluated as well as air decking. A Red lake Lo-cam and a velocity of detonation recorder (VODR) are used to estimate stemming retention time and stemming ejection velocities. Downstream productivity rates including: shovel digging rates, crusher speed and crusher hangup counts are used to estimate fragmentation results. Digital image analysis is used to estimate size distributions.

  9. 7 CFR 51.2934 - Diameter.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apricots Definitions § 51.2934 Diameter. Diameter means the greatest diameter, measured through the center of the apricot, at right angles to a...

  10. 7 CFR 51.2934 - Diameter.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Apricots Definitions § 51.2934 Diameter. Diameter means the greatest diameter, measured through the center of the apricot, at right angles to a line running from the stem to the...

  11. 7 CFR 51.2934 - Diameter.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Apricots Definitions § 51.2934 Diameter. Diameter means the greatest diameter, measured through the center of the apricot, at right angles to a line running from the stem to the...

  12. 7 CFR 51.2934 - Diameter.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Apricots Definitions § 51.2934 Diameter. Diameter means the greatest diameter, measured through the center of the apricot, at right angles to a line running from the stem to the...

  13. 7 CFR 51.2934 - Diameter.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apricots Definitions § 51.2934 Diameter. Diameter means the greatest diameter, measured through the center of the apricot, at right angles to a...

  14. Effects of pellet diameter during and after lactation on feed intake of piglets pre- and postweaning.

    PubMed

    van den Brand, H; Wamsteeker, D; Oostindjer, M; van Enckevort, L C M; van der Poel, A F B; Kemp, B; Bolhuis, J E

    2014-09-01

    Effects of 2 pellet diameters for piglets pre- and postweaning on feed intake, BW, and feed-related behavior were studied in 3 experiments. In Exp. 1, 19 litters were provided with pellets of 2 and 12 mm in diameter in a choice-feeding setup from d 4 of lactation onward. From d 4 to 18, piglets preferred the 12-mm diameter pellet over the 2-mm diameter pellet (519 vs. 168 g/pen; P < 0.001). In Exp. 2, 39 litters were provided with creep feed of either 2- or 10-mm diameter pellets. Feed intake from d 3 to 17 was higher in litters provided the 10-mm diameter pellet than the 2-mm diameter pellet (1,752 vs. 1,101 g/pen; P < 0.001). Piglet BW at weaning did not differ between treatments. Treatment × day of lactation interactions were found for time spent eating, interest in eating, and time spent suckling. Time spent eating and interest in eating increased with time. This increase was lower in the litters provided with the 10-mm diameter pellet. Time spent suckling remained the same in litters provided with 2-mm diameter pellets but decreased in time in litters provided the 10-mm diameter pellets. Experiment 3 was set up as a 2 × 2 factorial design with pellet diameter both pre- and postweaning as factors. During lactation, 18 litters were provided creep feed of either 2 or 12 mm in pellet diameter. At weaning, each litter was split into 2 comparable half litters and each half litter was provided with feed of 2 or 12 mm in diameter. Feed intake was higher in the 12-mm diameter pellet litters than in the 2-mm ones from d 4 to 11 of lactation (P < 0.01). Pellet diameter provided after weaning did not affect BW gain or feed intake. Piglets provided the 12-mm diameter pellet before weaning, however, had a higher BW gain (2,060 vs. 2,606 g/pig; P = 0.003) and feed intake (2,772 vs. 3,173 g/pig; P = 0.04) and a lower feed conversion ratio (P = 0.03) between d 0 and 10 after weaning than piglets provided the 2-mm diameter pellet before weaning. Postweaning pellet diameter

  15. Ultrasound guided percutaneous EVAR success is predicted by vessel diameter

    PubMed Central

    Bensley, Rodney P.; Hurks, Rob; Huang, Zhen; Pomposelli, Frank; Hamdan, Allen; Wyers, Mark; Chaikof, Elliot; Schermerhorn, Marc L.

    2012-01-01

    Introduction Ultrasound guided access allows for direct visualization of the access artery during percutaneous endovascular aortic aneurysm repair. We hypothesize that the use of ultrasound guidance allowed us to safely increase the utilization of percutaneous endovascular aortic aneurysm repair to almost all patients and decrease access complications. Methods A retrospective chart review of all elective endovascular aortic aneurysm repairs, both abdominal and descending thoracic, from 2005-2010 was performed. Patients were identified using ICD9 codes and stratified based on access type: percutaneous vs. cutdown. We examined the success rate of percutaneous access and the cause of failure. Sheath size was large (18-24 Fr) or small (12-16 Fr). Minimum access vessel diameter was also measured. Outcomes were wound complications (infections or clinically significant hematomas that delayed discharge or required transfusion), operative and incision time, length of stay, and discharge disposition. Predictors of percutaneous failure were identified. Results 168 patients (296 arteries) had percutaneous access (P-EVAR) while 131 patients (226 arteries) had femoral cutdown access (C-EVAR). Ultrasound guided access was introduced in 2007. P-EVAR increased from zero cases in 2005 to 92.3% of all elective cases in 2010. The success rate with percutaneous access was 96%. Failures requiring open surgical repair of the artery included 7 for hemorrhage and 6 for flow limiting stenosis or occlusion of the femoral artery. P-EVAR had fewer wound complications (0.7% vs. 7.4%, P = .001) shorter operative time (153.3 vs. 201.5 minutes, P < .001) and larger minimal access vessel diameter (6.7 mm vs. 6.1 mm, P < .01). Patients with failed percutaneous access had smaller minimal access vessel diameters when compared to successful P-EVAR (4.9 mm vs. 6.8 mm, P < .001). More failures occurred in small sheaths than large ones (7.4% vs. 1.9%, P = .02). Access vessel diameter < 5 mm is predictive

  16. Influence of wall thickness and diameter on arterial shear wave elastography: a phantom and finite element study

    NASA Astrophysics Data System (ADS)

    Maksuti, Elira; Bini, Fabiano; Fiorentini, Stefano; Blasi, Giulia; Urban, Matthew W.; Marinozzi, Franco; Larsson, Matilda

    2017-04-01

    Quantitative, non-invasive and local measurements of arterial mechanical properties could be highly beneficial for early diagnosis of cardiovascular disease and follow up of treatment. Arterial shear wave elastography (SWE) and wave velocity dispersion analysis have previously been applied to measure arterial stiffness. Arterial wall thickness (h) and inner diameter (D) vary with age and pathology and may influence the shear wave propagation. Nevertheless, the effect of arterial geometry in SWE has not yet been systematically investigated. In this study the influence of geometry on the estimated mechanical properties of plates (h  =  0.5–3 mm) and hollow cylinders (h  =  1, 2 and 3 mm, D  =  6 mm) was assessed by experiments in phantoms and by finite element method simulations. In addition, simulations in hollow cylinders with wall thickness difficult to achieve in phantoms were performed (h  =  0.5–1.3 mm, D  =  5–8 mm). The phase velocity curves obtained from experiments and simulations were compared in the frequency range 200–1000 Hz and showed good agreement (R 2  =  0.80  ±  0.07 for plates and R 2  =  0.82  ±  0.04 for hollow cylinders). Wall thickness had a larger effect than diameter on the dispersion curves, which did not have major effects above 400 Hz. An underestimation of 0.1–0.2 mm in wall thickness introduces an error 4–9 kPa in hollow cylinders with shear modulus of 21–26 kPa. Therefore, wall thickness should correctly be measured in arterial SWE applications for accurate mechanical properties estimation.

  17. Fine Structure in the Mm-Wavelength Spectra of the Active Region

    NASA Astrophysics Data System (ADS)

    Sawant, H. S.; Cecatto, J. R.

    1990-11-01

    RESUMEN. Faltan observaciones solares espectrosc6picas en la longitud de onda milimetrica. Hay sugerencias de que se puede superponer una fi na estructura en frecuencia a la componente-S de la regi6n solar activa, asi como a la componente del brote en las longitudes de onda milimetri- cas. Se ha desarrollado un receptor de alta sensibilidad de pasos de frecuencia que opera en el intervalo de 23-18 GHz con una resoluci6n de 1 GHz y resoluci6n de tiempo variable entre 1.2 y 96 sec, usando la an- tena de Itapetinga de 13.7-m para estudiar la estructura fina en frecuencia y tiempo. Discutimos el espectro en longitud de onda-mm en re- giones activas y su evoluci6n en el tiempo. El estudio de Ia evoluci6n en el tiempo de la regi6n activa en AR 5569 observada el 29 de junio de 1989, sugiere la existencia de estructuras finas como funci6n deltiempo. ABSTRACT. There is a lack of mm-wavelength spectroscopic solar observations. There are suggestions that a fine structure in frequency may be superimposed on the S-component of solar active region as well as on the burst component at inm-wavelengths. To study fine structure in frequency and time, a high sensitivity step frequency receiver operating in the frequency range 23-18 GHz with frequency resolution of 1 GHz and variable time resolution 1.2 to 96 sec, using 13.7 m diameter Itapetinga radome covered antenna, has been developed. Here, we discuss mm-wavelength spectra of active regions and their time evolution. Study of time evolution of an active region AR 5569 observed on 29th June, 1989 suggests existence of fine structures as a function of time. ( Ck : SUN-ACTIVITY - SUN-RADIO RADIATION

  18. Effect of needle insertion depth and apical diameter on irrigant extrusion in simulated immature permanent teeth.

    PubMed

    Aksel, Hacer; Askerbeyli, Sevinc; Canbazoglu, Cigdem; Serper, Ahmet

    2014-01-01

    The aim of this study was to compare the amount of irrigant extrusion in simulated immature permanent teeth when the apical diameter and needle insertion depth were varied. Thirty single-rooted maxillary incisors with straight root canals were selected. The root length was standardized to a length of 9 mm. The teeth were divided into two experimental groups according to the degree of apical enlargement (n = 15). The apices were enlarged to a diameter of 1.10 mm or 1.70 mm by using a #3 or #6 peeso reamer, respectively, to simulate immature teeth. The irrigation solution was applied 2 or 4 mm short of the working length (WL) in each experimental group. The glass vial model was used for the collection of extruded irrigant beyond the root apex. A two-way repeated measures analysis of variance test showed that there was no significant difference between different needle insertion depths (2 and 4 mm short of the WL) in the group with an apical diameter of 1.70 mm (p > 0.05). In the group with an apical diameter of 1.10 mm, a 32% increase in irrigant extrusion was observed when the needle was positioned at 2 mm (p < 0.05). Regarding the effect of apical diameter, the group with a diameter of 1.70 mm showed more apical extrusion of the irrigant (34% increase for the needle positioned at 2 mm and 68% increase for the needle positioned at 4 mm). It was observed that the needle insertion depth and apical diameter have a significant effect on irrigant extrusion in immature permanent teeth.

  19. Latest developments of large-diameter c-axis sapphire grown by CHES method

    NASA Astrophysics Data System (ADS)

    Richard Schwerdtfeger, C.; Ullal, Saurabh; Shetty, Raj; Filgate, Joshua; Dhanaraj, Govindhan

    2014-05-01

    Large diameter c-axis crystal growth of sapphire boules up to 50 kg is in production at many sites world-wide. It has long been known that c-axis growth of sapphire could be the most cost-effective way to produce large diameter substrates for LED applications compared to a-axis growth with orthogonal coring due to the extremely large size boule required to core large diameter cores from the side of the boule. This paper will discuss the latest improvements, characterization, material utilizations, and crystal quality of boules designed specifically for 6-in., 8-in., and 10-in. wafer production. Improvements and continued R&D in slicing, polishing, and MOCVD of 6-in. and 8-in. sapphire has poised the industry for a rapid shift to larger diameter substrates, if the cores can be cost-effective. ARC Energy's CHES technology can produce 170 mm diameter boules optimized for 6-in. (150 mm) diameter wafer production. Additionally it can produce 8-in. or 10-in. diameter cores directly from 220 mm or 260 mm diameter boules, respectively. The latest developments, both equipment and process, will be discussed along with the resulting boule and core quality. Cost reductions for these large diameter cores will be shown to provide much more cost-effective 6-in. and 8-in. substrates. This low-cost enabling technology is poised to spur stable and long-term LED industry growth.

  20. Mm-size bistable zipping dielectric elastomer actuators for integrated microfluidics

    NASA Astrophysics Data System (ADS)

    Maffli, Luc; Rosset, Samuel; Shea, Herbert R.

    2013-04-01

    We report on a new structure of Dielectric Elastomer Actuators (DEAs) called zipping DEAs, which have a set of unique characteristics that are a good match for the requirements of electrically-powered integrated microfluidic pumping and/or valving units as well as Braille displays. The zipping DEAs operate by pulling electrostatically an elastomer membrane in contact with the rigid sidewalls of a sloped chamber. In this work, we report on fully functional mm-size zipping DEAs that demonstrate a complete sealing of the chamber sidewalls and a tunable bistable behavior, and compare the measurements with an analytical model. Compared to our first generation of devices, we are able vary the sidewall angle and benefit therefore from more flexibility to study the requirements to make fully functional actuators. In particular, we show that with Nusil CF19 as membrane material (1.2 MPa Young's modulus), it is possible to zip completely 2.3 mm diameter chambers with 15° and 21° sidewalls angle equibiaxially prestretched to λ0=1.12 and 15° chambers with λ0=1.27.

  1. MCT detectors: from IR to sub-mm and mm wavelength bands

    NASA Astrophysics Data System (ADS)

    Sizov, F. F.; Vasiliev, V. V.; Gumenjuk-Sichevska, J. V.; Kamenev, Yu. E.; Dvoretsky, S. A.; Mikhailov, N. N.

    2008-09-01

    Modern technology advances combined with unique physical properties of mercury cadmium telluride (MCT) material, empower low-signal applications in technical vision systems. Properties of MCT detectors manufactured from LPE and MBE epilayers and their dependences on thickness and doping both for IR and THz regions are discussed. It is shown by comparison of experimental data and modeling of I-V dark current characteristics that MCT photodiode ultimate electrical characteristics are limited by diffusion current in n+-n--p junctions and by current via the deep traps in the gap with position Et= 0.7 Eg above the valence band and concentrations Nt = (1.0-5.5)•1015 cm-3 which are comparable with donor concentration in n--region Nd = (1.1-1.8)•1015 cm-3. Detector array parameters for a wavelength range 8-12 microns are: detectivity D*=1.9•1011 cm•Hz1/2/W, noise equivalent difference temperature NEDT ~ 9 mK, dynamical resistance R ~ 4Â.109 Ohm for the reverse biases ΔV = 0.1-0.2 V. Also, it is shown that MCT layers can be successfully used as sub-mm or mm wave ambient temperature or moderately cooled hot electron bolometers. Thus, in addition to the wavelength range from SWIR to VLIR, where the MCT detectors are employed mainly as photodiodes or photoresistors, they can be used as sub-mm or mm wave detectors in the range from 190 microns to 8 mm. They can be employed here as semiconductor hot electron bolometers (SHEB). Measurements performed at electromagnetic wave frequencies ν = 37, 55, 77 GHz, and also at 0.89 and 1.58 THz with non-optimized Hg0.8Cd0.2Te bolometer prototype, has confirmed the basic concepts of SHEB. At ν = 0.89 THz, 77 GHz and 37 GHz the signal temperature dependencies were measured too. At 77 K the SHEB sensitivity at ν = 37 and 77 GHz is increasing up to two orders compared to room temperature data. The sensitivity Sν ~ 2 V/W at 300 K, and calculated both Johnson-Nyquist and generation-recombination noise values give estimations of

  2. Hydrodynamic Model with Binary Particle Diameters to Predict Axial Voidage Profile in a CFB Combustor

    NASA Astrophysics Data System (ADS)

    Li, J. J.; Zhang, H.; Yang, H. R.; Wu, Y. X.; Lu, J. F.; Yue, G. X.

    A hydrodynamic model with binary particle diameters was developed to better predict axial voidage profile in a CFB combustor. In the model, the CFB is regarded as a superposition of two sub-beds, a fast fluidized bed in the upper riser with a characteristic particle diameter of O.2mm and a bubbling fluidized bed or turbulent bed in the bottom riser with a characteristic particle diameter of 2mm. Furthermore, a variable critical particle diameter whose terminal velocity equals to the superficial gas velocity was employed to determine which flow regime the particle belongs to. The results show that binary particle diameter model has the advantages in describing wide particle diameter distribution while reducing the complexity of computation. The model was verified by the field data of voidage profile in a 300MW CFB boiler.

  3. 7 CFR 51.2656 - Diameter.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades for Sweet Cherries 1 Definitions § 51.2656 Diameter. Diameter means the greatest dimension measured at right angles to a line from the stem to the blossom end of the cherry....

  4. Prediction of moderate or severe pulmonary hypertension by main pulmonary artery diameter and main pulmonary artery diameter/ascending aorta diameter in pulmonary embolism.

    PubMed

    Sanal, Shirin; Aronow, Wilbert S; Ravipati, Gautham; Maguire, George P; Belkin, Robert N; Lehrman, Stuart G

    2006-01-01

    We investigated the accuracy of computed tomographic measurements of main pulmonary artery diameter (MPAD) and of MPAD/ascending aorta diameter (AAD) in predicting moderate or severe pulmonary hypertension in 190 patients with acute pulmonary embolism. A pulmonary artery systolic pressure of > or = 50 mm Hg measured by Doppler echocardiography was considered moderate or severe pulmonary hypertension. A MPAD of > 28.6 mm and a MPAD/AAD ratio of > or = 1.00 measured by computed tomography were considered abnormal. A MPAD of > 28.6 mm had a 75% sensitivity and specificity, a 52% positive predictive value, a 89% negative predictive value, a 3.0 likelihood ratio for a positive test, and a 0.33 likelihood ratio for a negative test in predicting moderate or severe pulmonary hypertension. A MPAD/AAD ratio of > or = 1.00 had a 59% sensitivity, a 82% specificity, a 55% positive predictive value, a 84% negative predictive value, a 3.3 likelihood ratio for a positive test, and a 0.50 likelihood ratio for a negative test.

  5. 7 CFR 51.587 - Diameter.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Diameter. 51.587 Section 51.587 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Celery Definitions § 51.587 Diameter. Diameter means... lowest outer branch to the base....

  6. 7 CFR 51.587 - Diameter.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Diameter. 51.587 Section 51.587 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Celery Definitions § 51.587 Diameter. Diameter means... lowest outer branch to the base....

  7. 7 CFR 51.587 - Diameter.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Diameter. 51.587 Section 51.587 Agriculture... Standards for Celery Definitions § 51.587 Diameter. Diameter means the greatest dimension of the stalk measured at a point 2 inches above the point of attachment of the lowest outer branch to the base....

  8. 7 CFR 51.587 - Diameter.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Diameter. 51.587 Section 51.587 Agriculture... Standards for Celery Definitions § 51.587 Diameter. Diameter means the greatest dimension of the stalk measured at a point 2 inches above the point of attachment of the lowest outer branch to the base....

  9. Development and evaluation of elastomeric hollow fiber membranes as small diameter vascular graft substitutes.

    PubMed

    Mercado-Pagán, Ángel E; Kang, Yunqing; Findlay, Michael W; Yang, Yunzhi

    2015-04-01

    Engineering of small diameter (<6mm) vascular grafts (SDVGs) for clinical use remains a significant challenge. Here, elastomeric polyester urethane (PEU)-based hollow fiber membranes (HFMs) are presented as an SDVG candidate to target the limitations of current technologies and improve tissue engineering designs. HFMs are fabricated by a simple phase inversion method. HFM dimensions are tailored through adjustments to fabrication parameters. The walls of HFMs are highly porous. The HFMs are very elastic, with moduli ranging from 1-4MPa, strengths from 1-5MPa, and max strains from 300-500%. Permeability of the HFMs varies from 0.5-3.5×10(-6)cm/s, while burst pressure varies from 25 to 35psi. The suture retention forces of HFMs are in the range of 0.8 to 1.2N. These properties match those of blood vessels. A slow degradation profile is observed for all HFMs, with 71 to 78% of the original mass remaining after 8weeks, providing a suitable profile for potential cellular incorporation and tissue replacement. Both human endothelial cells and human mesenchymal stem cells proliferate well in the presence of HFMs up to 7days. These results demonstrate a promising customizable PEU HFMs for small diameter vascular repair and tissue engineering applications.

  10. Ultrasonographic Measurement of Normal Common Bile Duct Diameter and its Correlation with Age, Sex and Anthropometry

    PubMed Central

    Mehra, Simmi; Lal, Vivek

    2014-01-01

    Background: Ultrasonography is the diagnostic method of choice for visualization and rational work-up of abdominal organs. The dilatation of the common bile duct helps distinguish obstructive from non-obstructive causes of jaundice. Availability of normal measurements of the common bile duct is therefore important. There exists significant variations in the anthropometric features of various populations, regions and races. Aim: Study was conducted to obtain data on sonographically measured diameters of common bile duct in a series of normal Rajasthani population and to measure its correlation with age, sex and anthropometry. Setting and Design: Cross-sectional hospital-based study conducted at Mahatma Gandhi Medical College and Hospital, Jaipur, India. Materials and Methods: Study included 200 participants with equal proportion belonging to either sex. Common bile duct was measured at three locations- at the porta hepatis, in the most distal aspect of head of pancreas and mid-way between these points. Anthropometric measurements including height, weight, chest circumference, circumference at transpyloric plane, circumference at umbilicus and circumference at hip were obtained using standard procedures. Statistical Analysis: Univariable analysis with measures of frequency and standard deviation and bivariable analysis using correlation. Results: Mean age of study subjects was 34.5 years (Range 18-85 years). Mean diameters of the common bile duct in the three locations were: proximal, 4.0 mm (SD 1.02 mm); middle, 4.1 mm (SD 1.01 mm); and distal, 4.2 mm (SD 1.01 mm) and overall mean for all measures 4.1 mm (SD 1.01 mm). Average diameter ranged from 2.0 mm to 7.9 mm, with 95 percent of the subjects having a diameter of less than 6 mm. We observed a statistically significant relation of common bile duct with age, along with a linear trend. There was no statistically significant difference in common bile duct diameter between male and female subjects. The diameter did

  11. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability to Subpart MM General...

  12. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability to Subpart MM General...

  13. Diameter of basalt columns derived from fracture mechanics bifurcation analysis.

    PubMed

    Bahr, H-A; Hofmann, M; Weiss, H-J; Bahr, U; Fischer, G; Balke, H

    2009-05-01

    The diameter of columnar joints forming in cooling basalt and drying starch increases with decreasing growth rate. This observation can be reproduced with a linear-elastic three-dimensional fracture mechanics bifurcation analysis, which has been done for a periodic array of hexagonal columnar joints by considering a bifurcation mode compatible with observations on drying starch. In order to be applicable to basalt columns, the analysis has been carried out with simplified stationary temperature fields. The critical diameter differs from the one derived with a two-dimensional model by a mere factor of 1/2. By taking into account the latent heat released at the solidification front, the results agree fairly well with observed column diameters.

  14. Large Diameter, Radiative Extinction Experiments with Decane Droplets in Microgravity

    NASA Technical Reports Server (NTRS)

    Easton, John; Tien, James; Dietrich, Daniel

    1999-01-01

    The extinction of a diffusion flame is of fundamental interest in combustion science. Linan, Law, and Chung and Law analytically and experimentally determined an extinction boundary in terms of droplet diameter and pressure for a single droplet due to Damkohler, or blowoff, extinction. More recently, other researchers demonstrated extinction due to finite rate kinetics in reduced gravity for free droplets of heptane. Chao modeled the effect of radiative heat loss on a quasi-steady spherically symmetric single droplet burning in the absence of buoyancy. They determined that for increasing droplet diameter, a second limit can be reached such that combustion is no longer possible. This second, larger droplet diameter limit arises due to radiative heat loss, which increases with increasing droplet and flame diameter. This increase in radiative heat loss arises due to an increase in the surface area of the flame. Recently, Marchese modeled fuel droplets with detailed chemistry and radiative effects, and compared the results to other work. The modeling also showed the importance of radiative loss and radiative extinction Experiments examined the behavior of a large droplet of decane burning in reduced gravity onboard the NASA Lewis DC-9 aircraft, but did not show a radiative extinction boundary due to g-jitter (Variations in gravitational level and direction) effects. Dietrich conducted experiments in the reduced gravity environment of the Space Shuttle. This work showed that the extinction diameter of methanol droplets increased when the initial diameter of the droplets was large (in this case, approximately 5 mm). Theoretical results agreed with these experimental results only when the theory included radiative effects . Radiative extinction was experimentally verified by Nayagam in a later Shuttle mission. The following work focuses on the combustion and extinction of a single fuel droplet. The goal is to experimentally determine a large droplet diameter limit that

  15. Augmented PMMA distribution: improvement of mechanical property and reduction of leakage rate of a fenestrated pedicle screw with diameter-tapered perforations.

    PubMed

    Tan, Quan-Chang; Wu, Jian-Wei; Peng, Fei; Zang, Yuan; Li, Yang; Zhao, Xiong; Lei, Wei; Wu, Zi-Xiang

    2016-06-01

    OBJECTIVE This study investigated the optimum injection volume of polymethylmethacrylate (PMMA) to augment a novel fenestrated pedicle screw (FPS) with diameter-tapered perforations in the osteoporotic vertebral body, and how the distribution characteristics of PMMA affect the biomechanical performance of this screw. METHODS Two types of FPSs were designed (FPS-A, composed of 6 perforations with an equal diameter of 1.2 mm; and FPS-B, composed of 6 perforations each with a tapered diameter of 1.5 mm, 1.2 mm, and 0.9 mm from tip to head. Each of 28 human cadaveric osteoporotic vertebrae were randomly assigned to 1 of 7 groups: FPS-A1.0: FPS-A+1.0 ml PMMA; FPS-A1.5: FPS-A+1.5 ml PMMA; FPS-A2.0: FPS-A+2.0 ml PMMA; FPS-B1.0: FPS-B+1.0 ml PMMA; FPS-B1.5: FPS-B+1.5 ml PMMA; FPS-B2.0: FPS-B+2.0 ml PMMA; and conventional pedicle screws (CPSs) without PMMA. After the augmentation, 3D CT was performed to assess the cement distribution characteristics and the cement leakage rate. Axial pullout tests were performed to compare the maximum pullout force thereafter. RESULTS The CT construction images showed that PMMA bone cement formed a conical mass around FPS-A and a cylindrical mass around FPS-B. When the injection volume was increased from 1.0 ml to 2.0 ml, the distribution region of the PMMA cement was enlarged, the PMMA was distributed more posteriorly, and the risk of leakage was increased. When the injection volume reached 2.0 ml, the risk of cement leakage was lower for screws having diameter-tapered perforations. The pullout strengths of the augmented FPS-A groups and FPS-B groups were higher than that of the CPS group (p < 0.0001). All FPS-B groups had a higher pullout strength than the FPS-A groups. CONCLUSIONS The diameter of the perforations affects the distribution of PMMA cement. The diameter-tapered design enabled PMMA to form larger bone-PMMA interfaces and achieve a relatively higher pullout strength, although statistical significance was not reached. Study

  16. Experimental characterization and system simulations of depth of interaction PET detectors using 0.5 mm and 0.7 mm LSO arrays.

    PubMed

    James, Sara St; Yang, Yongfeng; Wu, Yibao; Farrell, Richard; Dokhale, Purushottam; Shah, Kanai S; Cherry, Simon R

    2009-07-21

    Small animal PET scanners may be improved by increasing the sensitivity, improving the spatial resolution and improving the uniformity of the spatial resolution across the field of view. This may be achieved by using PET detectors based on crystal elements that are thin in the axial and transaxial directions and long in the radial direction, and by employing depth of interaction (DOI) encoding to minimize the parallax error. With DOI detectors, the diameter of the ring of the PET scanner may also be decreased. This minimizes the number of detectors required to achieve the same solid angle coverage as a scanner with a larger ring diameter and minimizes errors due to non-collinearity of the annihilation photons. In this study, we characterize prototype PET detectors that are finely pixelated with individual LSO crystal element sizes of 0.5 mm x 0.5 mm x 20 mm and 0.7 mm x 0.7 mm x 20 mm, read out at both ends by position sensitive avalanche photodiodes (PSAPDs). Both a specular reflector and a diffuse reflector were evaluated. The detectors were characterized based on the ability to clearly resolve the individual crystal elements, the DOI resolution and the energy resolution. Our results indicate that a scanner based on any of the four detector designs would offer improved spatial resolution and more uniform spatial resolution compared to present day small animal PET scanners. The greatest improvements to spatial resolution will be achieved when the detectors employing the 0.5 mm x 0.5 mm x 20 mm crystals are used. Monte Carlo simulations were performed to demonstrate that 2 mm DOI resolution is adequate to ensure uniform spatial resolution for a small animal PET scanner geometry using these detectors. The sensitivity of such a scanner was also simulated using Monte Carlo simulations and was shown to be greater than 10% for a four ring scanner with an inner diameter of 6 cm, employing 20 detectors per scanner ring.

  17. Experimental characterization and system simulations of depth of interaction PET detectors using 0.5 mm and 0.7 mm LSO arrays

    NASA Astrophysics Data System (ADS)

    James, Sara St; Yang, Yongfeng; Wu, Yibao; Farrell, Richard; Dokhale, Purushottam; Shah, Kanai S.; Cherry, Simon R.

    2009-07-01

    Small animal PET scanners may be improved by increasing the sensitivity, improving the spatial resolution and improving the uniformity of the spatial resolution across the field of view. This may be achieved by using PET detectors based on crystal elements that are thin in the axial and transaxial directions and long in the radial direction, and by employing depth of interaction (DOI) encoding to minimize the parallax error. With DOI detectors, the diameter of the ring of the PET scanner may also be decreased. This minimizes the number of detectors required to achieve the same solid angle coverage as a scanner with a larger ring diameter and minimizes errors due to non-collinearity of the annihilation photons. In this study, we characterize prototype PET detectors that are finely pixelated with individual LSO crystal element sizes of 0.5 mm × 0.5 mm × 20 mm and 0.7 mm × 0.7 mm × 20 mm, read out at both ends by position sensitive avalanche photodiodes (PSAPDs). Both a specular reflector and a diffuse reflector were evaluated. The detectors were characterized based on the ability to clearly resolve the individual crystal elements, the DOI resolution and the energy resolution. Our results indicate that a scanner based on any of the four detector designs would offer improved spatial resolution and more uniform spatial resolution compared to present day small animal PET scanners. The greatest improvements to spatial resolution will be achieved when the detectors employing the 0.5 mm × 0.5 mm × 20 mm crystals are used. Monte Carlo simulations were performed to demonstrate that 2 mm DOI resolution is adequate to ensure uniform spatial resolution for a small animal PET scanner geometry using these detectors. The sensitivity of such a scanner was also simulated using Monte Carlo simulations and was shown to be greater than 10% for a four ring scanner with an inner diameter of 6 cm, employing 20 detectors per scanner ring.

  18. A 10-mm MR-Conditional Unidirectional Pneumatic Stepper Motor

    PubMed Central

    Chen, Yue; Mershon, Christopher D.; Tse, Zion Tsz Ho

    2014-01-01

    Magnetic resonance (MR) conditional robotic devices facilitate accurate interventional procedures under MR imaging (MRI) guidance. For this purpose, a compact (10-mm diameter) MR-conditional stepper motor is presented. The device features seven key components, which contribute to a dense and easy to fabricate design. Alternating bursts of pressurized air and vacuum can drive the motor in 60° per step to achieve a maximum torque of 2.4 mNm. The relationship between torque and angular speed was investigated to demonstrate motor performance under different loading conditions. The stepper motor was tested in a GE 3T MRI scanner to verify its MR-compatibility. A maximum artifact width of 3 mm was measured in MRI images and a maximum signal-to-noise ratio reduction of 2.49% was recorded. PMID:25419104

  19. cis-1,2-Dichloroethylene

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 09 / 006 F www.epa.gov / iris TOXICOLOGICAL REVIEW OF cis - 1,2 - DICHLOROETHYLENE and trans - 1,2 - DICHLOROETHYLENE ( CAS Nos . cis : 156 - 59 - 2 ; trans : 156 - 60 - 5 ; mixture : 540 - 59 - 0 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS )

  20. Ultra-small diameter coils for treatment of intracranial aneurysms

    PubMed Central

    Miller, Timothy; Beaty, Narlin; Puri, Ajit; Gandhi, Dheeraj

    2015-01-01

    This study reports our initial clinical experience treating very small intracranial aneurysms using only Target® Nano™ coils. Retrospective angiographic and clinical analysis was performed on a non-randomized single arm registry of all intracranial aneurysms treated with only Target® Nano™ coils (1 mm and 1.5 mm diameter only) during a 12 month period at two academic hospitals. Fourteen patients with 14 intracranial aneurysms were treated. The maximum diameter of saccular aneurysms treated ranged from 1.5 to 3.5 mm; minimum aneurysm diameter was 1.1 to 2 mm. The immediate complete aneurysm occlusion rate was 86% (12/14), and a small residual within the aneurysm was seen in 14% (2/14) of cases. Packing density from coils ranged between 24% and 83% (mean 51%). The immediate complication rate was 0% (0/14). The angiographic/MR angiography follow-up period was 22 to 70 weeks (mean 37 weeks) with an overall complete occlusion rate of 9/11 (81%), recurrence in 18% (2/11), and lack of follow-up in three cases, two due to death during hospitalization and one procedure not yet due for imaging follow-up. Both patients who died presented with brain aneurysm ruptures prior to treatment. Both recurrences were retreated with repeat coiling procedures. Our initial results using only Target® Nano™ coils for the endovascular treatment of very small intracranial aneurysms have demonstrated initial good safety and efficacy profiles. PMID:25934775

  1. Application of MM wave therapy in radiology

    SciTech Connect

    Avakian, R.S.; Gasparyan, L.V.

    1995-12-31

    The authors studied the effects of MM wave electromagnetic radiation influence on patients, affected by X-ray radiation during the reparation works after Chernobyl nuclear power plant exposure. They compared results of treatment of two groups of patients: (1) control group patients received only basis therapy; (2) testing group, 10 patients received basis therapy and MM wave influence. The authors used the wide band noise generator `Artsakh - 2` for local irradiation on the acupuncture points. Their data proved that low intensity MM waves have immunocorrective, antioxidant effects, and MM wave therapy is a perspective method for treatment of patients with radiological pathology.

  2. Correlation of axial blood velocity to venular and arteriolar diameter in the human eye in vivo.

    PubMed

    Koutsiaris, Aristotle G

    2015-01-01

    The axial blood velocity (Vax) association with microvessel diameter (D) was studied at 104 different postcapillary venules (4 μm <  D <  24 μm) and 30 different precapillary arterioles (6 μm≤D≤12 μm) in the human conjunctiva of normal healthy humans. Venular diameter sizes were classified as "very small" (Group 1, 4.4 μm≤D <  8.9 μm), "small" (Group 2, 8.9 μm≤D <  13.8 μm), "medium" (Group 3, 13.8 μm≤D <  19.1 μm) and "large" (Group 4, 19.1 μm≤D≤23.5). The Spearman's correlation coefficient (rs) in all 4 venular groups was less than 0.36 and not statistically significant (n = 26, p≥0.08). Similar correlation results were observed for the arteriolar group (rs) ≈ 0) for the peak systolic, the average and the end systolic axial velocities. Vax was significantly (p <  0.001) lower in Group 1 in comparison to that in Group 2 and significantly (p <  0.01) lower in Group 2 in comparison to that in Group 3. However, Vax was not significantly lower in Group 3 in comparison to that in Group 4. Average Vax and standard deviation was 0.48 ± 0.13, 0.64 ± 0.16, 0.82 ± 0.25 and 0.88 ± 0.32 mm/s for Groups 1, 2, 3 and 4 respectively. The above results reinforce the importance of measuring D in microvascular hemodynamics. Higher diameters suggest higher axial velocities but Vax does not change significantly within the limits of each of the aforementioned groups.

  3. Automated image analysis for diameters and branching points of cerebral penetrating arteries and veins captured with two-photon microscopy.

    PubMed

    Sugashi, Takuma; Yoshihara, Kouichi; Kawaguchi, Hiroshi; Takuwa, Hiroyuki; Ito, Hiroshi; Kanno, Iwao; Yamada, Yukio; Masamoto, Kazuto

    2014-01-01

    The present study was aimed to characterize 3-dimensional (3D) morphology of the cortical microvasculature (e.g., penetrating artery and emerging vein), using two-photon microscopy and automated analysis for their cross-sectional diameters and branching positions in the mouse cortex. We observed that both artery and vein had variable cross-sectional diameters across cortical depths. The mean diameter was similar for both artery (17 ± 5 μm) and vein (15 ± 5 μm), and there were no detectable differences over depths of 50-400 μm. On the other hand, the number of branches was slightly increased up to 400-μm depth for both the artery and vein. The mean number of branches per 0.1 mm vessel length was 1.7 ± 1.2 and 3.8 ± 1.6 for the artery and vein, respectively. This method allows for quantification of the large volume data of microvascular images captured with two-photon microscopy. This will contribute to the morphometric analysis of the cortical microvasculature in functioning brains.

  4. Pupil Diameter Tracks Lapses of Attention

    PubMed Central

    Murphy, Peter R.; Nieuwenhuis, Sander

    2016-01-01

    Our ability to sustain attention for prolonged periods of time is limited. Studies on the relationship between lapses of attention and psychophysiological markers of attentional state, such as pupil diameter, have yielded contradicting results. Here, we investigated the relationship between tonic fluctuations in pupil diameter and performance on a demanding sustained attention task. We found robust linear relationships between baseline pupil diameter and several measures of task performance, suggesting that attentional lapses tended to occur when pupil diameter was small. However, these observations were primarily driven by the joint effects of time-on-task on baseline pupil diameter and task performance. The linear relationships disappeared when we statistically controlled for time-on-task effects and were replaced by consistent inverted U-shaped relationships between baseline pupil diameter and each of the task performance measures, such that most false alarms and the longest and most variable response times occurred when pupil diameter was both relatively small and large. Finally, we observed strong linear relationships between the temporal derivative of pupil diameter and task performance measures, which were largely independent of time-on-task. Our results help to reconcile contradicting findings in the literature on pupil-linked changes in attentional state, and are consistent with the adaptive gain theory of locus coeruleus-norepinephrine function. Moreover, they suggest that the derivative of baseline pupil diameter is a potentially useful psychophysiological marker that could be used in the on-line prediction and prevention of attentional lapses. PMID:27768778

  5. Diameter Effect In Initiating Explosives, Numerical Simulations

    SciTech Connect

    Lefrancois, A.; Benterou, J.; Roeske, F.; Roos, E.

    2006-02-10

    The ability to safely machine small pieces of HE with the femtosecond laser allows diameter effect experiments to be performed in initiating explosives in order to study the failure diameter, the reduction of the detonation velocity and curvature versus the diameter. The reduced diameter configuration needs to be optimized, so that the detonation products of the first cylinder will not affect the measurement of the detonation velocity of the second cylinder with a streak camera. Different 2D axi-symmetrical configurations have been calculated to identify the best solution using the Ignition and Growth reactive flow model for LX16 Pellet with Ls-Dyna.

  6. MM Algorithms for Some Discrete Multivariate Distributions.

    PubMed

    Zhou, Hua; Lange, Kenneth

    2010-09-01

    The MM (minorization-maximization) principle is a versatile tool for constructing optimization algorithms. Every EM algorithm is an MM algorithm but not vice versa. This article derives MM algorithms for maximum likelihood estimation with discrete multivariate distributions such as the Dirichlet-multinomial and Connor-Mosimann distributions, the Neerchal-Morel distribution, the negative-multinomial distribution, certain distributions on partitions, and zero-truncated and zero-inflated distributions. These MM algorithms increase the likelihood at each iteration and reliably converge to the maximum from well-chosen initial values. Because they involve no matrix inversion, the algorithms are especially pertinent to high-dimensional problems. To illustrate the performance of the MM algorithms, we compare them to Newton's method on data used to classify handwritten digits.

  7. 78 FR 64475 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure... large diameter carbon and alloy seamless standard, line, and pressure pipe (over 4\\1/2\\ inches) from... duty order on certain large diameter carbon and alloy seamless standard, line, and pressure pipe...

  8. Stellar angular diameters from occultation observations.

    NASA Astrophysics Data System (ADS)

    Qian, B.-C.

    This paper reviews the history of measuring stellar angular diameters from lunar occultation observations and the techniques of data analysis. Several effects which can affect the results of measurement are discussed. The author finds that there may be systematic errors in angular diameters measured by various observatories for Aldebaran.

  9. Multimedia contents production system (MM-CPS)

    NASA Astrophysics Data System (ADS)

    Roser, Miguel; Villegas, Paulo; Simon, Maria; Hernandez-Gil, J. F.; Aguado, Isidro

    1996-01-01

    A present characterized by deep worldwide changes, and a future where social relations and behaviors are going to undergo a substantial change need new telecommunications services in order to allow people to get closer, facilitate their daily tasks and place at their disposal multimedia information to be accessed anywhere and at any time. These new services are very dependent on the contents to be included in the applications. The purpose of this paper is to describe an universal MM contents production system (MM-CPS), which allows the generation of coded data files suitable to be included in MM-servers.

  10. Measurement of wire diameter by optical diffraction

    NASA Astrophysics Data System (ADS)

    Khodier, Soraya A.

    2004-02-01

    A combined interference and diffraction pattern, in the form of equidistant interference fringes, resulting from illuminating a vertical metallic wire by a laser beam is analyzed to measure the diameter of four standard wires. The diameters range from 170 to 450 μm. It is found that the error in the diameter measurements increases for small metallic wires and for small distances between the wire and the screen due to scattering effects. The intensity of the incident laser beam was controlled by a pair of sheet polaroids to minimize the scattered radiation. The used technique is highly sensitive, but requires controlled environmental conditions and absence of vibration effects. The expanded uncertainty for k=2 is calculated and found to decrease from U(D)=±1.45 μm for the wire of nominal diameter 170 μm to ±0.57 μm for the diameter 450 μm.

  11. Serial Measurements of Splanchnic Vein Diameters in Rats Using High-Frequency Ultrasound

    PubMed Central

    Seitz, Bridget M.; Krieger-Burke, Teresa; Fink, Gregory D.; Watts, Stephanie W.

    2016-01-01

    The purpose of this study was to investigate serial ultrasound imaging in rats as a fully non-invasive method to (1) quantify the diameters of splanchnic veins in real time as an indirect surrogate for the capacitance function of those veins, and (2) assess the effects of drugs on venous dimensions. A 21 MHz probe was used on anesthetized male Sprague–Dawley rats to collect images containing the portal vein (PV), superior mesenteric vein (SMV), abdominal inferior vena cava (IVC), and splenic vein (SpV; used as a landmark in timed studies) and the abdominal aorta (AA). Stable landmarks were established that allowed reproducible quantification of cross-sectional diameters within an animal. The average diameters of vessels measured every 5 min over 45 min remained within 0.75 ± 0.15% (PV), 0.2 ± 0.09% (SMV), 0.5 ± 0.12% (IVC), and 0.38 ± 0.06% (AA) of baseline (PV: 2.0 ± 0.12 mm; SMV: 1.7 ± 0.04 mm; IVC: 3.2 ± 0.1 mm; AA: 2.3 ± 0.14 mm). The maximal effects of the vasodilator sodium nitroprusside (SNP; 2 mg/kg, i.v. bolus) on venous diameters were determined 5 min post SNP bolus; the diameters of all noted veins were significantly increased by SNP, while mean arterial pressure (MAP) decreased 29 ± 4 mmHg. By contrast, administration of the venoconstrictor sarafotoxin (S6c; 5 ng/kg, i.v. bolus) significantly decreased PV and SpV, but not IVC, SMV, or AA, diameters 5 min post S6c bolus; MAP increased by 6 ± 2 mmHg. In order to determine if resting splanchnic vein diameters were stable over much longer periods of time, vessel diameters were measured every 2 weeks for 8 weeks. Measurements were found to be highly reproducible within animals over this time period. Finally, to evaluate the utility of vein imaging in a chronic condition, images were acquired from 4-week deoxycorticosterone acetate salt (DOCA-salt) hypertensive and normotensive (SHAM) control rats. All vessel diameters increased from baseline while MAP increased (67 ± 4 mmHg) in DOCA-salt rats

  12. Note: Computer controlled rotation mount for large diameter optics

    NASA Astrophysics Data System (ADS)

    Rakonjac, Ana; Roberts, Kris O.; Deb, Amita B.; Kjærgaard, Niels

    2013-02-01

    We describe the construction of a motorized optical rotation mount with a 40 mm clear aperture. The device is used to remotely control the power of large diameter laser beams for a magneto-optical trap. A piezo-electric ultrasonic motor on a printed circuit board provides rotation with a precision better than 0.03° and allows for a very compact design. The rotation unit is controlled from a computer via serial communication, making integration into most software control platforms straightforward.

  13. MM Algorithms for Geometric and Signomial Programming.

    PubMed

    Lange, Kenneth; Zhou, Hua

    2014-02-01

    This paper derives new algorithms for signomial programming, a generalization of geometric programming. The algorithms are based on a generic principle for optimization called the MM algorithm. In this setting, one can apply the geometric-arithmetic mean inequality and a supporting hyperplane inequality to create a surrogate function with parameters separated. Thus, unconstrained signomial programming reduces to a sequence of one-dimensional minimization problems. Simple examples demonstrate that the MM algorithm derived can converge to a boundary point or to one point of a continuum of minimum points. Conditions under which the minimum point is unique or occurs in the interior of parameter space are proved for geometric programming. Convergence to an interior point occurs at a linear rate. Finally, the MM framework easily accommodates equality and inequality constraints of signomial type. For the most important special case, constrained quadratic programming, the MM algorithm involves very simple updates.

  14. QM/MM methods in inorganic chemistry.

    PubMed

    Bo, Carles; Maseras, Feliu

    2008-06-14

    Quantum mechanics/molecular mechanics (QM/MM) methods are a useful tool for the computational study of inorganic systems. They allow a quantitative description of systems larger than those treatable with pure QM methods, in principle with a comparable quality. QM/MM calculations are being currently applied to the research in a variety of topics, including structural effects of ligand bulk, selectivity in homogeneous catalysis and mechanical embedding in heterogeneous catalysis. The QM/MM approach is also useful for the separation of steric and electronic contributions, and as an auxiliary tool for geometry optimization when full QM methods are mandatory. The power of QM/MM methods in inorganic chemistry is illustrated in this Perspective with a summary of recent representative applications.

  15. Analogue saturation limit of single and double 10 mm microchannel plate photomultiplier tubes

    NASA Astrophysics Data System (ADS)

    Milnes, J. S.; Conneely, T. M.; Horsfield, C. J.

    2016-11-01

    Photek are a well-established supplier of microchannel plate (MCP) photomultiplier tubes (PMTs) to the inertial confinement fusion community. The analogue signals produced at the major inertial confinement fusion facilities cover many orders of magnitude, therefore understanding the upper saturation limit of MCP-PMTs to large low rate signals takes on a high importance. Here we present a study of a single and a double MCP-PMT with 10 mm diameter active area. The saturation was studied for a range of optical pulse widths from 4 ns to 100 ns and at a range of electron gain values: 103 to 104 for the single and 104 to 106 for the double. We have shown that the saturation level of ˜1.2 nC depends only on the integrated charge of the pulse and is independent of pulse width and gain over this range, but that the level of charge available in deep saturation is proportional to the operating gain.

  16. 1,1,2-Trichloroethane

    Integrated Risk Information System (IRIS)

    1,1,2 - Trichloroethane ; CASRN 79 - 00 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  17. 1,2,4-Tribromobenzene

    Integrated Risk Information System (IRIS)

    1,2,4 - Tribromobenzene ; CASRN 615 - 54 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  18. 1,1,2-Trichloropropane

    Integrated Risk Information System (IRIS)

    1,1,2 - Trichloropropane ; CASRN 598 - 77 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  19. 1,2,3-Trichloropropane

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 08 / 010F www.epa.gov / iris TOXICOLOGICAL REVIEW OF 1,2,3 - TRICHLOROPROPANE ( CAS No . 96 - 18 - 4 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2009 U.S . Environmental Protection Agency Washington DC i DISCLAIMER This document ha

  20. trans-1,2-Dichloroethylene

    Integrated Risk Information System (IRIS)

    trans - 1,2 - Dichloroethylene ; CASRN 156 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for No

  1. 1,2,4-Trichlorobenzene

    Integrated Risk Information System (IRIS)

    1,2,4 - Trichlorobenzene ; CASRN 120 - 82 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  2. 1,2-Epoxybutane (EBU)

    Integrated Risk Information System (IRIS)

    1,2 - Epoxybutane ( EBU ) ; CASRN 106 - 88 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  3. Platform switching on wide-diameter external hex implants: a finite element analysis

    PubMed Central

    Sivolella, Stefano; Bressan, Eriberto; Berengo, Mario; Stellini, Edoardo

    2013-01-01

    Objectives: The objective of this work was to use finite element analysis to compare the effect of forces coming to bear on abutments 4.1 or 5.0 mm in diameter connected to a 5.0 mm implant (i.e. with or without platform switching). Study design: A 3D CAD model of a 5 x 11.5 mm external hex implant was developed, complete with a connection screw and either of two abutments, one 4.1 and the other 5 mm in diameter, to assess the influence of two loading conditions, i.e. 200 N loaded either axially or off center on the top of the abutment. Results and conclusions: In the symmetrically loaded models, greater stresses were transmitted to the bone in the area below the neck of the implant in the case of the wider-diameter abutment. When the narrower abutment was considered, the stress lines remained confined to the metal and were transferred to the bone in a more distal position. When the stresses in the bone where compared under non-symmetrical loading of the larger- and smaller-diameter abutments, the stresses reached lower values in the latter case. These findings indicate that platform switching (i.e. coupling a 4.1 mm abutment with a 5 mm implant) achieves a better, more even distribution of the peri-implant stresses deriving from simulated occlusal loads on the bone margins. Key words:Platform switching, finite element analysis, implant. PMID:24455061

  4. Patterns of variability in the diameter of lateral roots in the banana root system.

    PubMed

    Lecompte, François; Pagès, Loïc; Ozier-Lafontaine, Harry

    2005-09-01

    The relative importance of root system structure, plant carbon status and soil environment in the determination of lateral root diameter remains unclear, and was investigated in this study. Banana (Musa acuminata) plants were grown at various moderate levels of soil compaction in two distinct experiments, in a field experiment (FE) and in a glasshouse experiment (GE). Radiant flux density was 5 times lower in GE. The distribution of root diameter was measured for several root branching orders. Root diameters ranged between 0.09 and 0.52 mm for secondary roots and between 0.06 and 0.27 mm for tertiary roots. A relationship was found between the diameter of the parent bearing root and the median diameter of its laterals, which appears to be valid for a wide range of species. Mean lateral root diameter increased with distance to the base of the root and decreased with branching density [number of lateral roots per unit length of bearing root (cm(-1))]. Typical symptoms of low light availability were observed in GE. In this case, lateral root diameter variability was reduced. Although primary root growth was affected by soil compaction, no effects on lateral root diameter were observed.

  5. Impact Structures: What Does Crater Diameter Mean?

    NASA Astrophysics Data System (ADS)

    Turtle, E. P.; Pierazzo, E.; Collins, G. S.; Osinski, G. R.; Melosh, H. J.; Morgan, J. V.; Reimold, W. U.; Spray, J. G.

    2004-03-01

    Crater diameter is an important parameter in energy scaling and impact simulations. However, disparate types of data make the use of consistent metrics difficult. We suggest a consistent terminology and discuss it in the context of several examples.

  6. Growth of nanostructures with controlled diameter

    DOEpatents

    Pfefferle, Lisa; Haller, Gary; Ciuparu, Dragos

    2009-02-03

    Transition metal-substituted MCM-41 framework structures with a high degree of structural order and a narrow pore diameter distribution were reproducibly synthesized by a hydrothermal method using a surfactant and an anti-foaming agent. The pore size and the mesoporous volume depend linearly on the surfactant chain length. The transition metals, such as cobalt, are incorporated substitutionally and highly dispersed in the silica framework. Single wall carbon nanotubes with a narrow diameter distribution that correlates with the pore diameter of the catalytic framework structure were prepared by a Boudouard reaction. Nanostructures with a specified diameter or cross-sectional area can therefore be predictably prepared by selecting a suitable pore size of the framework structure.

  7. Substrate diameter and compliance affect the gripping strategies and locomotor mode of climbing boa constrictors.

    PubMed

    Byrnes, Greg; Jayne, Bruce C

    2010-12-15

    Arboreal habitats pose unique challenges for locomotion as a result of their narrow cylindrical surfaces and discontinuities between branches. Decreased diameter of branches increases compliance, which can pose additional challenges, including effects on stability and energy damping. However, the combined effects of substrate diameter and compliance are poorly understood for any animal. We quantified performance, kinematics and substrate deformation while boa constrictors (Boa constrictor) climbed vertical ropes with three diameters (3, 6 and 9 mm) and four tensions (0.5, 1.0, 1.5 and 2.0 body weights). Mean forward velocity decreased significantly with both decreased diameter and increased compliance. Both diameter and compliance had numerous effects on locomotor kinematics, but diameter had larger and more pervasive effects than compliance. Locomotion on the largest diameter had a larger forward excursion per cycle, and the locomotor mode and gripping strategy differed from that on the smaller diameters. On larger diameters, snakes primarily applied opposing forces at the same location on the rope to grip. By contrast, on smaller diameters forces were applied in opposite directions at different locations along the rope, resulting in increased rope deformation. Although energy is likely to be lost during deformation, snakes might use increased surface deformation as a strategy to enhance their ability to grip.

  8. Controlling the Fiber Diameter during Electrospinning

    NASA Astrophysics Data System (ADS)

    Fridrikh, Sergey V.; Yu, Jian H.; Brenner, Michael P.; Rutledge, Gregory C.

    2003-04-01

    We present a simple analytical model for the forces that determine jet diameter during electrospinning as a function of surface tension, flow rate, and electric current in the jet. The model predicts the existence of a terminal jet diameter, beyond which further thinning of the jet due to growth of the whipping instability does not occur. Experimental data for various electrospun fibers attest to the accuracy of the model.

  9. Making Jointless Dual-Diameter Tubes

    NASA Technical Reports Server (NTRS)

    Kirkham, Kathleen E.

    1989-01-01

    Welds between sections having different diameters eliminated. Single tube made with integral tapered transition section between straight sections of different diameters and wall thicknesses. Made from single piece; contains no joints, welded or otherwise. Not prone to such weld defects as voids and need not be inspected for them. Tube fabricated by either of two methods: drawing or reduction. Both methods used to fabricate tubes of 316L corrosion-resistant stainless steel for use as heat-exchanger coil.

  10. Large diameter carbon-boron fiber

    NASA Technical Reports Server (NTRS)

    Veltri, R. D.; Jacob, B. A.; Galasso, F. S.

    1975-01-01

    Investigations concerned with a development of large-diameter carbon fibers are considered, taking into account the employment of vapor deposition techniques. In the experiments a carbon monofilament substrate is used together with reacting gases which consist of combinations of hydrogen, methane, and boron trichloride. It is found that the described approach can be used to obtain a large-diameter carbon filament containing boron. The filament has reasonable strength and modulus properties.

  11. Laparoscopic cholecystectomy using 2-mm instruments.

    PubMed

    Uranüs, S; Peng, Z; Kronberger, L; Pfeifer, J; Salehi, B

    1998-10-01

    Today, laparoscopic cholecystectomy is the method of choice for treatment of symptomatic gallbladder disorders. It minimizes effects of the operation that are independent of the gallbladder, such as trauma to the abdominal wall and other soft tissue. The surgical wounds were even smaller when 2-mm trocars were used. Laparoscopic cholecystectomy using 2-mm instruments was performed in a consecutive series of 14 patients with symptomatic gallstones. The procedure was completed in 12 cases, with conversion to open surgery in two cases. Intraoperative cholangiography was always performed. The postoperative course was always uneventful. The cosmetic effect was highly satisfactory. The procedure using 2-mm instruments could be indicated in selected patients with uncomplicated gallstone disease.

  12. Ultra-efficient Engine Diameter Study

    NASA Technical Reports Server (NTRS)

    Daggett, David L.; Brown, Stephen T.; Kawai, Ron T.

    2003-01-01

    Engine fan diameter and Bypass Ratio (BPR) optimization studies have been conducted since the beginning of the turbofan age with the recognition that reducing the engine core jet velocity and increasing fan mass flow rate generally increases propulsive efficiency. However, performance tradeoffs limit the amount of fan flow achievable without reducing airplane efficiency. This study identifies the optimum engine fan diameter and BPR, given the advanced Ultra-Efficient Engine Technology (UEET) powerplant efficiencies, for use on an advanced subsonic airframe. Engine diameter studies have historically focused on specific engine size options, and were limited by existing technology and transportation infrastructure (e.g., ability to fit bare engines through aircraft doors and into cargo holds). This study is unique in defining the optimum fan diameter and drivers for future 2015 (UEET) powerplants while not limiting engine fan diameter by external constraints. This report follows on to a study identifying the system integration issues of UEET engines. This Engine Diameter study was managed by Boeing Phantom Works, Seattle, Washington through the NASA Glenn Revolutionary Aero Space Engine Research (RASER) contract under task order 10. Boeing Phantom Works, Huntington Beach, completed the engine/airplane sizing optimization, while the Boeing Commercial Airplane group (BCA) provided design oversight. A separate subcontract to support the overall project was issued to Tuskegee University.

  13. The 1.2 micron CMOS technology

    NASA Technical Reports Server (NTRS)

    Pina, C. A.

    1985-01-01

    A set of test structures was designed using the Jet Propulsion Laboratory (JPL) test chip assembler and was used to evaluate the first CMOS-bulk foundry runs with feature sizes of 1.2 microns. In addition to the problems associated with the physical scaling of the structures, this geometry provided an additional set of problems, since the design files had to be generated in such a way as to be capable of being processed through p-well, n-well, and twin-well processing lines. This requirement meant that the files containing the geometric design rules as well as the structure design files had to produce process-insensitive designs, a requirement that does not apply to the more mature 3.0-micron CMOS feature size technology. Because of the photolithographic steps required with this feature size, the maximum allowable chip size was 10 x 10 mm, and this chip was divided into 24 project areas, with each area being 1.6 x 1.6 mm in size. The JPL-designed structures occupied 13 out of the 21 allowable project sizes and provided the only test information obtained from these three preliminary runs. The structures were used to successfully evaluate three different manufacturing runs through two separate foundries.

  14. The Use of Narrow Diameter Implants in the Molar Area

    PubMed Central

    Saad, M.; Assaf, A.; Gerges, E.

    2016-01-01

    Implant rehabilitations in the posterior jaw are influenced by many factors such as the condition of the remaining teeth, the force factors related to the patient, the quality of the bone, the maintenance of the hygiene, the limited bone height, the type and extent of edentulism, and the nature of the opposing arch. The gold standard is to place a regular diameter implant (>3.7 mm) or a wide one to replace every missing molar. Unfortunately, due to horizontal bone resorption, this option is not possible without lateral bone augmentation. In this situation, narrow diameter implant (NDI < 3.5 mm) could be the alternative to lateral bone augmentation procedures. This paper presents a clinical study where NDIs were used for the replacement of missing molars. They were followed up to 11 years. Special considerations were observed and many parameters were evaluated. NDI could be used to replace missing molar in case of moderate horizontal bone resorption if strict guidelines are respected. Yet, future controlled prospective clinical trials are required to admit their use as scientific evidence. PMID:27293436

  15. Estimation of the diameter of and iodine concentration within blood vessels using digital radiography devices.

    PubMed

    Kruger, R A

    1981-01-01

    A variety of digital radiographic and fluoroscopic devices have been developed which can isolate small concentrations of iodine within the cardiovascular system. Using these devices, time dependent subtraction images have been formed which only display opacified vasculature. Theory is presented and simple methods have been developed for determining vessel diameters and iodine concentration from such subtraction images. The methods have been verified using plexiglass and aluminum vessel phantoms imaged with a computerized radiography device. Using this device the diameter of a 5 mm diameter vessel could be determined to within 6% (0.28 mm) even though the pixel width in the digitized image corresponded to 1.34 mm. In the same vessel, it is estimated that an iodine concentration of 46 mg/cm3 could be determined with 10% accuracy.

  16. Turbulent Concentration of mm-Size Particles in the Protoplanetary Nebula: Scale-Dependent Cascades

    NASA Technical Reports Server (NTRS)

    Cuzzi, J. N.; Hartlep, T.

    2015-01-01

    The initial accretion of primitive bodies (here, asteroids in particular) from freely-floating nebula particles remains problematic. Traditional growth-by-sticking models encounter a formidable "meter-size barrier" (or even a mm-to-cm-size barrier) in turbulent nebulae, making the preconditions for so-called "streaming instabilities" difficult to achieve even for so-called "lucky" particles. Even if growth by sticking could somehow breach the meter size barrier, turbulent nebulae present further obstacles through the 1-10km size range. On the other hand, nonturbulent nebulae form large asteroids too quickly to explain long spreads in formation times, or the dearth of melted asteroids. Theoretical understanding of nebula turbulence is itself in flux; recent models of MRI (magnetically-driven) turbulence favor low-or- no-turbulence environments, but purely hydrodynamic turbulence is making a comeback, with two recently discovered mechanisms generating robust turbulence which do not rely on magnetic fields at all. An important clue regarding planetesimal formation is an apparent 100km diameter peak in the pre-depletion, pre-erosion mass distribution of asteroids; scenarios leading directly from independent nebula particulates to large objects of this size, which avoid the problematic m-km size range, could be called "leapfrog" scenarios. The leapfrog scenario we have studied in detail involves formation of dense clumps of aerodynamically selected, typically mm-size particles in turbulence, which can under certain conditions shrink inexorably on 100-1000 orbit timescales and form 10-100km diameter sandpile planetesimals. There is evidence that at least the ordinary chondrite parent bodies were initially composed entirely of a homogeneous mix of such particles. Thus, while they are arcane, turbulent concentration models acting directly on chondrule size particles are worthy of deeper study. The typical sizes of planetesimals and the rate of their formation can be

  17. Turbulent Concentration of MM-Size Particles in the Protoplanetary Nebula: Scaled-Dependent Multiplier Functions

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.; Hartlep, Thomas; Weston, B.; Estremera, Shariff Kareem

    2014-01-01

    The initial accretion of primitive bodies (asteroids and TNOs) from freely-floating nebula particles remains problematic. Here we focus on the asteroids where constituent particle (read "chondrule") sizes are observationally known; similar arguments will hold for TNOs, but the constituent particles in those regions will be smaller, or will be fluffy aggregates, and are unobserved. Traditional growth-bysticking models encounter a formidable "meter-size barrier" [1] (or even a mm-cm-size barrier [2]) in turbulent nebulae, while nonturbulent nebulae form large asteroids too quickly to explain long spreads in formation times, or the dearth of melted asteroids [3]. Even if growth by sticking could somehow breach the meter size barrier, other obstacles are encountered through the 1-10km size range [4]. Another clue regarding planetesimal formation is an apparent 100km diameter peak in the pre-depletion, pre-erosion mass distribution of asteroids [5]; scenarios leading directly from independent nebula particulates to this size, which avoid the problematic m-km size range, could be called "leapfrog" scenarios [6-8]. The leapfrog scenario we have studied in detail involves formation of dense clumps of aerodynamically selected, typically mm-size particles in turbulence, which can under certain conditions shrink inexorably on 100-1000 orbit timescales and form 10-100km diameter sandpile planetesimals. The typical sizes of planetesimals and the rate of their formation [7,8] are determined by a statistical model with properties inferred from large numerical simulations of turbulence [9]. Nebula turbulence can be described by its Reynolds number Re = L/eta sup(4/3), where L = ETA alpha sup (1/2) the largest eddy scale, H is the nebula gas vertical scale height, and a the nebula turbulent viscosity parameter, and ? is the Kolmogorov or smallest scale in turbulence (typically about 1km), with eddy turnover time t?. In the nebula, Re is far larger than any numerical simulation can

  18. Real-time diameter measurement using diffuse light

    NASA Astrophysics Data System (ADS)

    Luo, Xiaohe; Hui, Mei; Zhu, Qiudong; Wang, Shanshan

    2016-09-01

    A method for on-line rapid determination of the diameter of metallic cylinder is introduced in this paper. Under the radiation of diffuse light, there is a bright area close to the margin of metallic cylinder, and the method of this paper is based on the intensity distribution of the bright area. In this paper, with the radiation by a diffuse plane light with special shape, we present the relation expression of the distance between the peak point and the real edge of the cylinder and the distance between the diffuse light and the pinhole aperture of the camera. With the expression, the diameter of the cylinder to be measured can be calculated. In the experiments, monochromatic LED uniting with ground glass forms the diffuse light source, then the light irradiates the tested cylinder. After the cylinder, we use a lens with a front pinhole stop to choose the light into CMOS, then a computer is used to analyze images and export the measurement results. The measuring system using this method is very easily implemented, so it can realize the on-line rapid measurement. Experimental results are presented for six metallic cylinders with the diameter in 5 18mm range and roughness in Ra- 0.02um, and the precision reaches 3um.

  19. Assembly of mm-scale macrobridges with carbon nanotube bundles

    NASA Astrophysics Data System (ADS)

    Cao, Anyuan; Ajayan, P. M.; Ramanath, G.

    2003-07-01

    We report a chemical vapor deposition method for in situ bridging of mm-scale metal-contact patterns with bundles of multiwalled carbon nanotubes. The nanotube bundles synthesized from a hexane-ferrocene-thiophene mixture have a diameter of <50 μm and lengths up to millimeters, typically consisting of tens to hundreds of aligned nanotubes. These bundles are transported to the downstream end of the furnace, where they are captured by relief patterns of metal-contact tips. We can control the orientation and length of the nanotube bridges by preorganizing the metal tips to receive the bundles. This method is amenable to both scaling up, e.g., to create large-area arrays of nanotubes with contact electrodes, as well as scaling down, e.g., to bridge closely spaced contact structures.

  20. Validating a Nonhuman Primate Model of Super-Selective Intraophthalmic Artery Chemotherapy: Comparing Ophthalmic Artery Diameters

    PubMed Central

    Ditta, Lauren C.; Choudhri, Asim F.; Tse, Brian C.; Landers, Mark M.; Haik, Barrett G.; Steinle, Jena J.; Williams, J. Scott; Wilson, Matthew W.

    2012-01-01

    Purpose. Superselective intraophthalmic artery chemotherapy (SSIOAC) is being used for treatment of retinoblastoma; however, the hemodynamic consequences and toxicities are not fully known. We developed a nonhuman primate (NHP) model of SSIOAC and reported our clinical observations. For validation, we compared ophthalmic artery (OA) diameters between NHPs and children (<6 years). Methods. Endovascular cannulation of the right OA was performed three times each in six adult male Rhesus macaques. Angiographic OA images were obtained and measured, and postmortem OAs were histologically sectioned and measured. Retrospectively, computed tomography (CT) and magnetic resonance (MR) angiography images of the head in children and adolescents (as an adult reference) were used to measure the OA luminal diameter at its origin. Results. The median angiographic diameter of treated NHP OA origins (n = 6) was 1.06 mm (range 0.94–1.56). Histologic measurements (8 of 12 NHP OAs) gave a median diameter of 1.09 mm (range 0.95–1.41). In 98 children (from 169 consecutive CT and MR angiography studies; median age 1.01 years, range 0.01–5.74), 186 OAs were measurable at the origin (median luminal diameter 1.28 mm, range 0.82–2.00; P = 0.16 for the angiographic NHP diameters versus pediatric cohort). Angiographic measurements of 34 OAs (of 20 consecutive studies of adolescents; median age 16.55 years, range 14.40–18.18) gave a median luminal diameter of 1.45 mm (origin, range 1.13–1.66; P < 0.0001, adolescent versus pediatric). Conclusions. Measurements of the OA luminal diameter at its origin were similar between our NHP and pediatric cohort, validating our NHP model for testing both the hemodynamic consequences and toxicities of SSIOAC. PMID:23111611

  1. Littoral Combat Ship Mission Modules (LCS MM)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-443 Littoral Combat Ship Mission Modules (LCS MM) As of FY 2017 President’s Budget Defense...Estimate RDT&E - Research, Development, Test, and Evaluation SAR - Selected Acquisition Report SCP - Service Cost Position TBD - To Be Determined TY

  2. Excalibur Precision 155mm Projectiles (Excalibur)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-366 Excalibur Precision 155mm Projectiles (Excalibur) As of FY 2017 President’s Budget...Program Office Estimate RDT&E - Research, Development, Test, and Evaluation SAR - Selected Acquisition Report SCP - Service Cost Position TBD - To Be

  3. Optimizing digital 8mm drive performance

    NASA Technical Reports Server (NTRS)

    Schadegg, Gerry

    1993-01-01

    The experience of attaching over 350,000 digital 8mm drives to 85-plus system platforms has uncovered many factors which can reduce cartridge capacity or drive throughput, reduce reliability, affect cartridge archivability and actually shorten drive life. Some are unique to an installation. Others result from how the system is set up to talk to the drive. Many stem from how applications use the drive, the work load that's present, the kind of media used and, very important, the kind of cleaning program in place. Digital 8mm drives record data at densities that rival those of disk technology. Even with technology this advanced, they are extremely robust and, given proper usage, care and media, should reward the user with a long productive life. The 8mm drive will give its best performance using high-quality 'data grade' media. Even though it costs more, good 'data grade' media can sustain the reliability and rigorous needs of a data storage environment and, with proper care, give users an archival life of 30 years or more. Various factors, taken individually, may not necessarily produce performance or reliability problems. Taken in combination, their effects can compound, resulting in rapid reductions in a drive's serviceable life, cartridge capacity, or drive performance. The key to managing media is determining the importance one places upon their recorded data and, subsequently, setting media usage guidelines that can deliver data reliability. Various options one can implement to optimize digital 8mm drive performance are explored.

  4. Mm-wave power meter mount

    NASA Technical Reports Server (NTRS)

    Mullen, D. L.; Oltmans, D. A.; Stelzried, C. T.

    1968-01-01

    E-band thermistor mount and a technique for adjusting a temperature compensating thermistor to provide an electrically balanced bridge are used for measuring RF power in the mm-wavelength. The mount is relatively insensitive to temperature effects that cause measurement errors in single ended circuits.

  5. MM-122: High speed civil transport

    NASA Technical Reports Server (NTRS)

    Demarest, Bill; Anders, Kurt; Manchec, John; Yang, Eric; Overgaard, Dan; Kalkwarf, Mike

    1992-01-01

    The rapidly expanding Pacific Rim market along with other growing markets indicates that the future market potential for a high speed civil transport is great indeed. The MM-122 is the answer to the international market desire for a state of the art, long range, high speed civil transport. It will carry 250 passengers a distance of 5200 nm at over twice the speed of sound. The MM-122 is designed to incorporate the latest technologies in the areas of control systems, propulsions, aerodynamics, and materials. The MM-122 will accomplish these goals using the following design parameters. First, a double delta wing planform with highly swept canards and an appropriately area ruled fuselage will be incorporated to accomplish desired aerodynamic characteristics. Propulsion will be provided by four low bypass variable cycle turbofan engines. A quad-redundant fly-by-wire flight control system will be incorporated to provide appropriate static stability and level 1 handling qualities. Finally, the latest in conventional metallic and modern composite materials will be used to provide desired weight and performance characteristics. The MM-122 incorporates the latest in technology and cost minimization techniques to provide a viable solution to this future market potential.

  6. CCM3 to MM5 Data Conversion

    SciTech Connect

    Taylor, John; Mirin, Arthur

    2007-03-02

    The accompanying script (which uses the NCAR Command Language) ready output from the Community Climate Model Code, version 3 (CCM3) and converts it to input format for the Mesoscale Model, version 5 (MM5) code. The script utilizes a Fortran binary write routine.

  7. Influence of coronary artery diameter on eNOS protein content

    NASA Technical Reports Server (NTRS)

    Laughlin, M. H.; Turk, J. R.; Schrage, W. G.; Woodman, C. R.; Price, E. M.

    2003-01-01

    The purpose of this study was to test the hypothesis that the content of endothelial nitric oxide synthase (eNOS) protein (eNOS protein/g total artery protein) increases with decreasing artery diameter in the coronary arterial tree. Content of eNOS protein was determined in porcine coronary arteries with immunoblot analysis. Arteries were isolated in six size categories from each heart: large arteries [301- to 2,500-microm internal diameter (ID)], small arteries (201- to 300-microm ID), resistance arteries (151- to 200-microm ID), large arterioles (101- to 150-microm ID), intermediate arterioles (51- to 100-microm ID), and small arterioles(<50-microm ID). To obtain sufficient protein for analysis from small- and intermediate-sized arterioles, five to seven arterioles 1-2 mm in length were pooled into one sample for each animal. Results establish that the number of smooth muscle cells per endothelial cell decreases from a number of 10 to 15 in large coronary arteries to 1 in the smallest arterioles. Immunohistochemistry revealed that eNOS is located only in endothelial cells in all sizes of coronary artery and in coronary capillaries. Contrary to our hypothesis, eNOS protein content did not increase with decreasing size of coronary artery. Indeed, the smallest coronary arterioles had less eNOS protein per gram of total protein than the large coronary arteries. These results indicate that eNOS protein content is greater in the endothelial cells of conduit arteries, resistance arteries, and large arterioles than in small coronary arterioles.

  8. Excretion rates of indigestible plastic balls of different specific gravities and diameters in dairy cattle.

    PubMed

    Seyama, Tomohiro; Hirayasu, Hirofumi; Kasai, Koji

    2017-01-01

    We used plastic balls to investigate how their specific gravity and diameter affect excretion rate and rumination in dairy cattle, to develop a capsule that can be used for reaching the lower gastrointestinal tract without physical breakdown and/or degradation in the rumen. Twelve types of indigestible plastic balls composed of a combination of four specific gravities (0.95, 1.19, 1.41, or 2.20) and three diameters (3.97, 6.35, or 7.94 mm) were orally administered to lactating dairy cows, and the balls were collected from feces, after 120 h post-administration, to evaluate the recovery rate. Recovery rate of the balls with specific gravity 1.19 or 1.41 and diameter 6.35 or 7.94 mm was higher than those with specific gravity 0.95 or 2.20 and diameter 3.97 mm. The cumulative recovery rate at 24 and 48 h post-administration was higher for balls with specific gravity 1.19 than that for balls with other specific gravities. These results suggest that specific gravity 1.19 or 1.41 and diameters 6.35-7.94 mm are optimal for use in bypass capsules for administration to cattle. In addition, the passage time of capsules differed between specific gravities 1.19 and 1.41.

  9. DiameterJ: A validated open source nanofiber diameter measurement tool.

    PubMed

    Hotaling, Nathan A; Bharti, Kapil; Kriel, Haydn; Simon, Carl G

    2015-08-01

    Despite the growing use of nanofiber scaffolds for tissue engineering applications, there is not a validated, readily available, free solution for rapid, automated analysis of nanofiber diameter from scanning electron microscope (SEM) micrographs. Thus, the goal of this study was to create a user friendly ImageJ/FIJI plugin that would analyze SEM micrographs of nanofibers to determine nanofiber diameter on a desktop computer within 60 s. Additional design goals included 1) compatibility with a variety of existing segmentation algorithms, and 2) an open source code to enable further improvement of the plugin. Using existing algorithms for centerline determination, Euclidean distance transforms and a novel pixel transformation technique, a plugin called "DiameterJ" was created for ImageJ/FIJI. The plugin was validated using 1) digital synthetic images of white lines on a black background and 2) SEM images of nominally monodispersed steel wires of known diameters. DiameterJ analyzed SEM micrographs in 20 s, produced diameters not statistically different from known values, was over 10-times closer to known diameter values than other open source software, provided hundreds of times the sampling of manual measurement, and was hundreds of times faster than manual assessment of nanofiber diameter. DiameterJ enables users to rapidly and thoroughly determine the structural features of nanofiber scaffolds and could potentially allow new insights to be formed into fiber diameter distribution and cell response.

  10. Performance of and Pressure Elevation Formed by Small-diameter Microtubes Used in Constant-flow Sets

    PubMed Central

    Sohn, Sae Woon; Noh, Myounggyu D.; Lee, Jong-Hyun; Kim, Kyoung Nam; Ahn, Byung Heon

    2016-01-01

    Purpose We explored the performance of and pressure elevation caused by small-diameter microtubes used to reduce overfiltration. Methods Using a syringe pump-driven constant-flow setting (2 µL/min), pressures were measured for polytetrafluoroethylene (PTFE) microtubes 5 mm in length with inner diameters of 51, 64, and 76 µm and for polyether block amide (PEBAX) microtubes with an inner diameter of 76 µm. Experiments (using microtubes only) were initially performed in air, water, and enucleated pig eyes and were repeated under the same conditions using intraluminal 9/0 nylon stents. Results The pressures measured in air in 51-, 64-, and 76-µm-diameter PTFE microtubes differed significantly (22.1, 16.9, and 12.2 mmHg, respectively; p < 0.001), and that of the 76-µm-diameter PEBAX microtube was 15.8 mmHg (p < 0.001 compared to the 12.2 mmHg of the 76-µm-diameter PTFE microtube). The pressures measured in water also differed significantly among the three microtubes at 3.9, 3.0, and 1.4 mmHg, respectively, while that in the PEBAX microtube was 2.6 mmHg (all p < 0.001). Using the intraluminal stent, the pressure in water of the three different PTFE microtubes increased to 22.6, 18.0, and 4.1 mmHg, respectively, and that in the PEBAX microtube increased to 10.5 mmHg (all p < 0.001). Similar trends were evident when measurements were performed in pig eyes. Conclusions Although microtubes of smaller diameter experienced higher pressure in air, reduction of the inner diameter to 51 µm did not adequately increase the pressure attained in water or pig eyes. Insertion of an intraluminal stent effectively elevated the latter pressures. PEBAX microtubes created higher pressures than did PTFE microtubes. PMID:27247522

  11. Impact of implant diameter and length on stress distribution in osseointegrated implants: A 3D FEA study

    PubMed Central

    Eazhil, R.; Swaminathan, Siva Vadivel; Gunaseelan, Madhan; Kannan, G. Vijay; Alagesan, Chandrapandian

    2016-01-01

    Aims and Objectives: Dimension of dental implant is an important parameter which has a considerable impact on the biomechanical load transfer characters and its prognosis. Excessive stress in the bone–implant interface may result in the failure of the implant. The aim of this study was to evaluate the impact of implant diameter and length on neighboring tissues around the implant. The results of the study will help in developing a scientific methodology to select appropriate implant diameter and length. Materials and Methods: In this study, tapered implants of different diameter and length were numerically analyzed using bone–implant models developed from computed tomography generated images of mandible with osseointegrated implants. The impact of various diameters on stress distribution was examined using implants with a length of 13 mm and diameters of 3.5 mm, 4.3 mm and 5.0 mm. Implants with a diameter of 4.3 mm and lengths of 10 mm, 13 mm, 16 mm was developed to examine the impact of various implant length. All materials were assumed to be linearly elastic and isotropic. Masticatory load was applied in a natural direction, oblique to the occlusal plane. The Statistical Package for the Social Sciences software package was used for statistical analysis. Results: Maximum von Mises stresses were located around the implant neck. It was demonstrated that there was statistically significant decrease in von Mises stress as the implant diameter increased. Conclusion: Within the limitations of this study there was statistically significant decrease in von Mises stress as the implant diameter increased. PMID:28032053

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

    EPA Science Inventory

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

  13. Modular Small Diameter Vascular Grafts with Bioactive Functionalities

    PubMed Central

    Neufurth, Meik; Wang, Xiaohong; Tolba, Emad; Dorweiler, Bernhard; Schröder, Heinz C.; Link, Thorben; Diehl-Seifert, Bärbel; Müller, Werner E. G.

    2015-01-01

    We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV), with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC). Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP) and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD). These materials can be hardened by exposure to Ca2+ through formation of Ca2+ bridges between the polyanions, alginate, N,O-CMC, and polyP (alginate-Ca2+-N,O-CMC-polyP). The bTEBV are formed by pressing the hydrogel through an extruder into a hardening solution, containing Ca2+. In this universal scaffold of the bTEBV biomaterial, polycations such as poly(l-Lys), poly(d-Lys) or a His/Gly-tagged RGD peptide (three RGD units) were incorporated, which promote the adhesion of endothelial cells to the vessel surface. The mechanical properties of the biopolymer material (alginate-Ca2+-N,O-CMC-polyP-silica) revealed a hardness (elastic modulus) of 475 kPa even after a short incubation period in CaCl2 solution. The material of the artificial vascular grafts (bTEBVs with an outer size 6 mm and 1.8 mm, and an inner diameter 4 mm and 0.8 mm, respectively) turned out to be durable in 4-week pulsatile flow experiments at an alternating pressure between 25 and 100 mbar (18.7 and 75.0 mm Hg). The burst pressure of the larger (smaller) vessels was 850 mbar (145 mbar). Incorporation of polycationic poly(l-Lys), poly(d-Lys), and especially the His/Gly-tagged RGD peptide, markedly increased the adhesion of human, umbilical vein/vascular endothelial cells, EA.HY926 cells, to the surface of the hydrogel. No significant effect of the polyP samples on the clotting of human plasma is measured. We propose that the metabolically degradable

  14. Biologically Inspired mm-size Gliding UAV

    NASA Astrophysics Data System (ADS)

    Weihs, Daniel; Zussman, Eyal; Yarin, Alexander

    2002-11-01

    We present a first design of an unmanned aerial vehicle whose aerodynamic loads are carried by comb-like permeable surfaces. This concept was based on observation and analysis of the flight capabilities of the Thrip family of insects, whose have wings of this form and various plant seeds which use this concept to form an aerodynamic decelerator. This concept is only practical for at low Reynolds numbers, as the viscous trace of bodies moving in fluid becomes thicker as Re becomes smaller. When Re<1, a cylinder moving in fluid can drag along fluid up to several cylinder diameters. This drag effect can be used to produce a comb structure, where the ratio of comb rod to inter-rod distance can be up to 0.1 without significant throughflow, i.e. the comb is equivalent to a continuous surface. To demonstrate this principle, we have built artificial ``dandelion seeds", i.e. stable aerodynamic decelerators (parachutes) made of permeable light mats of submicron diameter nanofibers. We produced the nanofiber matrices (mats) by electrospinning of polymer solutions, obtaining fibers of 200-400 nm diameter. These fibers were then deposited on frames that serve to define the aerodynamic surfaces, thus producing the mat, with controllable density. For stability, the aerodynamic surfaces had positive dihedral ( inverted umbrella) forms with the fuselage hanging below. When dropped, the platforms fell freely through the air, apex down, reaching terminal velocity very quickly. By comparing the sink rate of the permeable structures with equivalent decelerators with continuous (Saran-wrap) surfaces we show that the permeable surfaces are equivalent to continuous surfaces, with significant weight savings, as long as the local Reynolds number is o(1).

  15. Large diameter astromast development, phase 1

    NASA Technical Reports Server (NTRS)

    Preiswerk, P. R.; Finley, L. A.; Knapp, K.

    1983-01-01

    Coilable-longeron lattice columns called Astromasts (trademark) were manufactured for a variety of spacecraft missions. These flight structures varied in diameter from 0.2 to 0.5 meter (9 to 19 in.), and the longest Astromast of this type deploys to a length of 30 meters (100 feet). A double-laced diagonal Astromast design referred to as the Supermast (trademark) which, because it has shorter baylengths than an Astromast, is approximately four times as strong. The longeron cross section and composite material selection for these structures are limited by the maximum strain associated with stowage and deployment. As a result, future requirements for deployable columns with high stiffness and strength require the development of both structures in larger diameters. The design, development, and manufacture of a 6.1-m-long (20-ft), 0.75-m-diameter (30-in.), double-laced diagonal version of the Astromast is described.

  16. Submicron diameter single crystal sapphire optical fiber

    DOE PAGES

    Hill, Cary; Homa, Daniel; Liu, Bo; ...

    2014-10-02

    In this work, a submicron-diameter single crystal sapphire optical fiber was demonstrated via wet acid etching at elevated temperatures. Etch rates on the order 2.3 µm/hr were achievable with a 3:1 molar ratio sulfuric-phosphoric acid solution maintained at a temperature of 343°C. A sapphire fiber with an approximate diameter of 800 nm was successfully fabricated from a commercially available fiber with an original diameter of 50 µm. The simple and controllable etching technique provides a feasible approach to the fabrication of unique waveguide structures via traditional silica masking techniques. The ability to tailor the geometry of sapphire optical fibers ismore » the first step in achieving optical and sensing performance on par with its fused silica counterpart.« less

  17. Submicron diameter single crystal sapphire optical fiber

    SciTech Connect

    Hill, Cary; Homa, Daniel; Liu, Bo; Yu, Zhihao; Wang, Anbo; Pickrell, Gary

    2014-10-02

    In this work, a submicron-diameter single crystal sapphire optical fiber was demonstrated via wet acid etching at elevated temperatures. Etch rates on the order 2.3 µm/hr were achievable with a 3:1 molar ratio sulfuric-phosphoric acid solution maintained at a temperature of 343°C. A sapphire fiber with an approximate diameter of 800 nm was successfully fabricated from a commercially available fiber with an original diameter of 50 µm. The simple and controllable etching technique provides a feasible approach to the fabrication of unique waveguide structures via traditional silica masking techniques. The ability to tailor the geometry of sapphire optical fibers is the first step in achieving optical and sensing performance on par with its fused silica counterpart.

  18. Systematic biases in radiometric diameter determinations

    NASA Technical Reports Server (NTRS)

    Spencer, John R.; Lebofsky, Larry A.; Sykes, Mark V.

    1989-01-01

    Radiometric diameter determinations are presently shown to often be significantly affected by the effect of rotation. This thermal effect of rotation depends not only on the object's thermal inertia, rotation rate, and pole orientation, but also on its temperature, since colder objects having constant rotation rate and thermal inertia will radiate less of their heat on the diurnal than on the nocturnal hemisphere. A disk-integrated beaming parameter of 0.72 is determined for the moon, and used to correct empirically for the roughness effects in thermophysical models; the standard thermal model is found to systematically underestimate cold object diameters, while overstating their albedos.

  19. Shaft Diameter Measurement Using Structured Light Vision.

    PubMed

    Liu, Siyuan; Tan, Qingchang; Zhang, Yachao

    2015-08-12

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  20. THERMAL EVALUATION OF DIFFERENT DRIFT DIAMETER SIZES

    SciTech Connect

    H.M. Wade

    1999-01-04

    The purpose of this calculation is to estimate the thermal response of a repository-emplaced waste package and its corresponding drift wall surface temperature with different drift diameters. The case examined is that of a 21 pressurized water reactor (PWR) uncanistered fuel (UCF) waste package loaded with design basis spent nuclear fuel assemblies. This calculation evaluates a 3.5 meter to 6.5 meter drift diameter range in increments of 1.0 meters. The time-dependent temperatures of interest, as determined by this calculation, are the spent nuclear fuel cladding temperature, the waste package surface temperature, and the drift wall surface temperature.

  1. Fabrication of 10nm diameter carbon nanopores

    SciTech Connect

    Radenovic, Aleksandra; Trepagnier, Eliane; Csencsits, Roseann; Downing, Kenneth H; Liphardt, Jan

    2008-09-25

    The addition of carbon to samples, during imaging, presents a barrier to accurate TEM analysis, the controlled deposition of hydrocarbons by a focused electron beam can be a useful technique for local nanometer-scale sculpting of material. Here we use hydrocarbon deposition to form nanopores from larger focused ion beam (FIB) holes in silicon nitride membranes. Using this method, we close 100-200nm diameter holes to diameters of 10nm and below, with deposition rates of 0.6nm per minute. I-V characteristics of electrolytic flow through these nanopores agree quantitatively with a one dimensional model at all examined salt concentrations.

  2. The truth about small-diameter implants.

    PubMed

    Christensen, Gordon J; Child, Paul L

    2010-05-01

    SDIs that are treatment planned correctly, placed and loaded properly, and are within a well-adjusted occlusion, are working in an excellent manner for the patients described in this article. It is time for those practitioners unfamiliar with SDIs and their uses to discontinue their discouragement of this technique. SDIs are easily placed, minimally invasive, and a true service to those patients described. They do not replace conventional diameter implants; however, they are a significant and important augmentation to the original root-form implant concept. There is obvious evidence of the growing acceptance of small-diameter implants by both general practitioners and specialists.

  3. Terahertz/mm wave imaging simulation software

    NASA Astrophysics Data System (ADS)

    Fetterman, M. R.; Dougherty, J.; Kiser, W. L., Jr.

    2006-10-01

    We have developed a mm wave/terahertz imaging simulation package from COTS graphic software and custom MATLAB code. In this scheme, a commercial ray-tracing package was used to simulate the emission and reflections of radiation from scenes incorporating highly realistic imagery. Accurate material properties were assigned to objects in the scenes, with values obtained from the literature, and from our own terahertz spectroscopy measurements. The images were then post-processed with custom Matlab code to include the blur introduced by the imaging system and noise levels arising from system electronics and detector noise. The Matlab code was also used to simulate the effect of fog, an important aspect for mm wave imaging systems. Several types of image scenes were evaluated, including bar targets, contrast detail targets, a person in a portal screening situation, and a sailboat on the open ocean. The images produced by this simulation are currently being used as guidance for a 94 GHz passive mm wave imaging system, but have broad applicability for frequencies extending into the terahertz region.

  4. Handling state-of-the-art large-diameter coiled tubing

    SciTech Connect

    Courville, P.

    1994-12-31

    Completion and workover demands placed on coiled tubing technology in the last 10 years have shown the limitations of small-diameter (1- to 1{1/2}-in.) coiled tubing. The small tubing tends to buckle when used at lengths greater than 1,500 ft in most horizontal applications. Large-diameter coiled tubing (up to 3{1/2} in.) provides greater flexibility of job design and increases horizontal reach possibilities for drilling, completion, and workover activities. Transportation and handling equipment to accommodate the larger, heavier tubing is naturally a critical component of the system. This paper will present the benefits of large-diameter coiled tubing including completion and workover for greater depth and more extended horizontal reach. It will also discuss the unique concerns of transportation and handling of large diameter tubing and associated equipment.

  5. A Novel Method for Characterizing the Diameter of Single-Wall Carbon Nanotubes by Optical Absorption Spectra

    NASA Astrophysics Data System (ADS)

    Saito, Takeshi; Ohmori, Shigekazu; Shukla, Bikau; Yumura, Motoo; Iijima, Sumio

    2009-09-01

    The potentiality of optical absorption spectroscopy (OAS) for the estimation of mean diameter of single-wall carbon nanotubes (SWCNTs) from electronic transition energies has been explored. The observed dependence of electronic transition energies of both metallic and semiconducting SWCNTs on their mean diameters clearly showed that transition energies scale inversely with the tube diameter. In the present study, the applicability of this estimation method has been experimentally confirmed for the diameter range of 1-2 nm and is expected to be useful for the characterization of wide range of diameters of SWNCTs.

  6. 7 CFR 51.320 - Diameter.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined...

  7. 7 CFR 51.320 - Diameter.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to... dimension of the apple determined by passing the apple through a round opening in any position....

  8. 7 CFR 51.320 - Diameter.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined...

  9. 7 CFR 51.320 - Diameter.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to a line from stem to blossom end. When measuring for maximum size, “diameter” means the smallest dimension of the apple determined...

  10. 7 CFR 51.320 - Diameter.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter” means the greatest dimension of the apple measured at right angles to... dimension of the apple determined by passing the apple through a round opening in any position....

  11. Reducing the diameters of computer networks

    NASA Technical Reports Server (NTRS)

    Bokhari, S. H.; Raza, A. D.

    1986-01-01

    Three methods of reducing the diameters of computer networks by adding additional processor to processor links under the constraint that no more than one I/O port be added to each processor are discussed. This is equivalent to adding edges to a given graph under the constraint that the degree of any node be increased, at most, by one.

  12. Small diameter symmetric networks from linear groups

    NASA Technical Reports Server (NTRS)

    Campbell, Lowell; Carlsson, Gunnar E.; Dinneen, Michael J.; Faber, Vance; Fellows, Michael R.; Langston, Michael A.; Moore, James W.; Multihaupt, Andrew P.; Sexton, Harlan B.

    1992-01-01

    In this note is reported a collection of constructions of symmetric networks that provide the largest known values for the number of nodes that can be placed in a network of a given degree and diameter. Some of the constructions are in the range of current potential engineering significance. The constructions are Cayley graphs of linear groups obtained by experimental computation.

  13. Reduced artery diameters in Klinefelter syndrome.

    PubMed

    Foresta, C; Caretta, N; Palego, P; Ferlin, A; Zuccarello, D; Lenzi, A; Selice, R

    2012-10-01

    Various epidemiological studies in relatively large cohorts of patients with Klinefelter syndrome (KS) described the increased morbidity and mortality in these subjects. Our aim was to study the structure and function of arteries in different districts to investigate in these subjects possible alterations. A total of 92 patients having non-mosaic KS, diagnosed in Centre for Human Reproduction Pathology at the University of Padova, and 50 age-matched healthy male controls were studied. Klinefelter syndrome subjects and controls evaluation included complete medical history, physical examination, measurement of concentrations of the reproductive hormones, lipidic and glycidic metabolism, AR function and sensitivity, ultrasound examinations (diameters, carotid intima-media thickness and brachial flow-mediated dilation) of brachial, common carotid and common femoral artery and abdominal aorta. Klinefelter syndrome patients showed significantly reduced artery diameters in all districts evaluated. On the contrary no statistically significant difference was found in cIMT and brachial FMD values between KS patients and controls. Furthermore, we found no statistically significant correlation of artery diameters with reproductive hormones, metabolic parameters, anthropometric measures and weighted CAG repeats. To our knowledge, this is the first study finding a reduced artery diameter in several districts in KS patients compared with that of normal male subjects and overlapping to that of female subjects. We have not an explanation for this phenomenon, even if a possible involvement of genes controlling the development of vascular system might be hypothesized, and further research is required to verify this hypothesis.

  14. Precision distances with spiral galaxy apparent diameters

    NASA Astrophysics Data System (ADS)

    Steer, Ian

    2016-01-01

    Spiral galaxy diameters offer the oldest extragalactic distance indicator known. Although outdated and hitherto imprecise, two spiral diameter-based distance indicators applied in the 1980s can be tested, calibrated, and re-established for precision era use, based on abundant redshift-independent distances data available in NED-D. Indicator one employs the largest Giant Spiral Galaxies, which have an absolute isophotal major diameter of ~70 +/- 10 kpc, offering standard ruler-based distances with <10% precision. Indicator two employs the diameter-magnitude relation for spirals in general, as a secondary indicator, offering ~20% precision. The ruler-based indicator is the only indicator with <10% precision able to independently calibrate type Ia supernovae-based distances at cosmological distances. The secondary-based indicator is the only indicator with 20% precision applicable to more galaxies than in current Tully-Fisher surveys. The primary indicator gives researchers a new tool to confirm or refute if, as currently believed, universal expansion is accelerating. The secondary indicator gives researchers a new path toward acquiring a more complete 3D picture of the local universe and potentially, because the majority of galaxies in the universe are spirals, the distant universe.

  15. Solar diameter with 2012 Venus Transit

    NASA Astrophysics Data System (ADS)

    Sigismondi, C.

    2012-06-01

    The role of Venus and Mercury transits is crucial to know the past history of the solar diameter. Through the W parameter, the logarithmic derivative of the radius with respect to the luminosity, the past values of the solar luminosity can be recovered. The black drop phenomenon affects the evaluation of the instants of internal and external contacts between the planetary disk and the solar limb. With these observed instants compared with the ephemerides the value of the solar diameter is recovered. The black drop and seeing effects are overcome with two fitting circles, to Venus and to the Sun, drawn in the undistorted part of the image. The corrections of ephemerides due to the atmospheric refraction will also be taken into account. The forthcoming transit of Venus will allow an accuracy on the diameter of the Sun better than 0.01 arcsec, with good images of the ingress and of the egress taken each second. Chinese solar observatories are in the optimal conditions to obtain valuable data for the measurement of the solar diameter with the Venus transit of 5/6 June 2012 with an unprecedented accuracy, and with absolute calibration given by the ephemerides.

  16. Measuring Solar Diameter with 2012 Venus Transits

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    The role of Venus and Mercury transits is crucial to know the past history of the solar diameter. Through the W parameter, the logarithmic derivative of the radius with respect to the luminosity, the past values of the solar luminosity can be recovered. The black drop phenomenon affects the evaluation of the instants of internal and external contacts between the planetary disk and the solar limb. With these observed instants compared with the ephemerides the value of the solar diameter is recovered. The black drop and seeing effects are overcome with two fitting circles, to Venus and to the Sun, drawn in the undistorted part of the image. The corrections of ephemerides due to the atmospheric refraction will also be taken into account. The forthcoming transit of Venus will allow an accuracy on the diameter of the Sun better than 0.01 arcsec, with good images of the ingress and of the egress taken each second. Chinese solar observatories are in the optimal conditions to obtain valuable data for the measurement of the solar diameter with the Venus transit of 5/6 June 2012 with an unprecedented accuracy, and with absolute calibration given by the ephemerides.

  17. Lengths, girths, and diameters of children's fingers from 3 to 10 years of age.

    PubMed

    Hohendorff, B; Weidermann, C; Burkhart, K J; Rommens, P M; Prommersberger, K J; Konerding, M A

    2010-05-20

    We obtained data on the lengths, girths, and diameters of the fingers of children from 3 to 10 years of age. A total of 160 children (78 girls, 82 boys) were examined in a cross-sectional investigation. The length of each finger of the right hand of every child was measured, as were the girths of the proximal, middle, and distal phalanges, and of the proximal and distal interphalangeal joint. The average length of the thumb was 49 (35-65) mm. The index and ring fingers both averaged 69 (index, 50-88; ring, 42-96) mm in length, while the middle and little fingers averaged 72 (57-100) and 56 (40-74) mm, respectively. Average diameter, calculated from the girth measurement, was 16 (11-22) mm for the thumb, 15 mm for both the index (9-22) and middle (10-21) fingers, 14 (10-20) and 13 (8-19) mm for the ring and little fingers, respectively. The average length of each finger increased by 37% from 3 to 10 years of age, average girth by 24%, and diameter increased by 20%. We observed no differences in length, girth, and diameter between the sexes. The dimensions of children's fingers are relevant to injuries from automatic, power-operated window lifters of motor vehicles because risk of injury to a finger jammed between an ascending window and the seal entry depends upon the diameter of the finger. Additionally, short fingers of young children can be jammed over almost their entire length in the oblique design of a car window seal entry.

  18. NWA 7034 Martian breccia: Ar/Ar ages of ca. 1.2 to 1.4 Ga

    NASA Astrophysics Data System (ADS)

    Cohen, B. E.; Mark, D. F.; Cassata, W.; Lee, M. R.; Smith, C. L.

    2015-12-01

    NWA 7034 and its paired stones are some of the oldest and most diverse of the Martian meteorites. They are complex polymict breccias of impact, igneous, and sedimentary clasts set in a dark grey matrix [1; 2]. The rock also contains angular mineral fragments, including K-feldspar, plagioclase feldspar, and pyroxene [1; 2]. Mineral fragments are often > 1 mm wide, and clasts can be > 1 cm. This diverse breccia assemblage indicates formation via repeated impact events, supported by Rb-Sr, Sm-Nd and U-Pb ages ranging from 1.3 to 4.4 Ga [1, 2, and references therein]. In this study we investigate the distribution of ages yielded by Ar/Ar, with nine aliquots analyzed to date, and additional analyses planned. In order to analyze only single phases, chips of matrix/clasts were restricted to visibly monomict fragments < 1 mm diameter, while mineral separates were analyzed as single crystals. Cosmogenic Ar corrections are from [3]. Analyses were undertaken at SUERC and Lawrence Livermore National Laboratory, and the results pooled. The bulk of aliquots (n = 8) yielded ages of ca. 1.2-1.4 Ga indicating a major thermal event occurred at around the same time as crystallization of the Nakhlite group of meteorites. Select step ages are considerably older (> 2 Ga), supporting results of other chronometers that much older material is present in this sample. These results also demonstrate that some older fragments retained Ar during breccia formation. [1] Wittmann A. et al. (2015) Meteoritics & Planet. Sci., 50, 326-352. [2] Santos A. R. et al. (2015) GCA, 157, 56-85. [3] Cassata W. S., and Borg L. E. (2015) 46th LPSC, Abstract #2742.

  19. Effects of implant diameter, drug loading and end-capping on praziquantel release from PCL implants.

    PubMed

    Li, Changyan; Cheng, Liang; Zhang, Yaqiong; Guo, Shengrong; Wu, Weiping

    2010-02-15

    Praziquantel (PZQ)-loaded poly(epsilon-caprolactone) (PCL) cylindrical implants were fabricated and characterized. Implant diameter (3, 4 and 8mm), drug loading (25% and 50%), and the end-capping were investigated to evaluate their effects on drug release. The evolution of implants with release time was conducted in terms of implant microstructure, crystallinity, drug content and molecular weight of PCL. The results showed that drug release was fastest for the implant with a diameter of 3mm and slowest for the implant with a diameter of 8mm; drug release from the implant with a drug content of 50% was faster than that from the implant with a drug content of 25%; the release of PZQ from the end-capped implants was slightly slower than that from the corresponding end-uncapped implants. The effect of drug loadings on PZQ release was related with diameter of the implants and the effect was weakened as diameter of the implants increased. The drug release data for all the implants were best fitted with Ritger-Peppas model, therefore Fickian diffusion was the predominant release mechanism. The evolution of implants with release time verified that PZQ was gradually released from the exterior to the interior of the implants.

  20. Evaluation of Correlation Between apical Diameter and File Size Using Propex Pixi Apex Locator

    PubMed Central

    Bolla, Nagesh; Varri, Sujana; Thummu, Jayaprakash; Vemuri, Sayesh; Mandava, Pragna

    2014-01-01

    Aim: Aim of this study is to evaluate the influence of critical diameter of apical foramen and file size using propex pixi apex locator in working length determination. Materials and Methods: In this study, ten single rooted teeth were selected. They were decoronated at cemento enamel junction. After determining the actual working length, they were embedded in alginate mold. Foramina were widened from 0.6mm to 0.8mm. The measurements were taken with electronic apex locator propex pixi with files from sizes 10 K to respective sizes. Statistical accuracy of propex pixi was calculated by using Anova test for different diameters and for the influence of file size. Results: Results showed that propex pixi apex locator was accurate when foramen diameter is 0.6 (60k file size), its accuracy diminished with increased foramen diameter Conclusion: Propex pixi is accurate for foramen diameter of 0.6mm, independent of file size. Its accuracy decreases as apical foramen widens, so care should be taken when using clinically. PMID:25654023

  1. Numerical investigations of small diameter two-phase closed thermosyphon

    NASA Astrophysics Data System (ADS)

    Naresh, Y.; Balaji, C.

    2016-09-01

    In this work, a CFD model is developed to simulate the working of a 6mm diameter two-phase closed thermosyphon using water as the working fluid. At each section (evaporator, condenser, adiabatic) of the thermosyphon, lumped equations have been developed to calculate the temperatures at corresponding sections. In order to process two phase flow inside the system, a user-defined function (UDF) has been developed and integrated with the CFD model. The volume of fluid (VOF) method is used to carry out the simulations in Ansys FLUENT 15 and the lumped equations are solved in MATLAB 2013a. Volume fractions and temperature profiles obtained from CFD simulations and the lumped parametric estimations are found to be in good agreement with the experimental results available in literature.

  2. Retrospective Comparison of Intermediate-term Efficacy of 350 mm2 Glaucoma Drainage Implants and Medium-sized 230-250 mm2 Implants

    PubMed Central

    Meyer, Alissa M; Rodgers, Cooper D; Zou, Baiming; Rosenberg, Nicole C; Webel, Aaron D

    2017-01-01

    ABSTRACT Aim To compare the intermediate-term efficacy of a large surface area Baerveldt 350 mm2 glaucoma drainage device (GDD) with medium surface area implants (Baerveldt 250 mm2 and Molteno 3, 230, or 245 mm2). Design This is a retrospective, nonrandomized comparative trial. Materials and methods A total of 94 eyes of 94 patients of mixed glaucoma diagnoses without any prior glaucoma surgical procedures and who had undergone a glaucoma drainage implant surgery with either a large Baerveldt 350 mm2 GDD or a medium-sized GDD (Baerveldt 250 mm2 or Molteno 230 or 245 mm2) were reviewed for intraocular pressure (IOP), number of glaucoma medications, and visual acuity (VA) preoperatively, and at 1, 2, and 3 years postprocedure. Results No significant differences were found in mean IOP, number of glaucoma medications used, and VA at 1, 2, and 3 years postoperatively. The rate of additional glaucoma procedures was similar between the two groups. Conclusion There is no clear evidence that a larger implant surface area beyond 230 to 250 mm2 is advantageous in providing intermediate-term IOP control. Clinical significance It may be technically easier to surgically place a GDD that does not need to have its wings placed underneath the recti muscles, and the IOP results are similar. How to cite this article Meyer AM, Rodgers CD, Zou B, Rosenberg NC, Webel AD, Sherwood MB. Retrospective Comparison of Intermediate-term Efficacy of 350 mm2 Glaucoma Drainage Implants and Medium-sized 230-250 mm2 Implants. J Curr Glaucoma Pract 2017;11(1):8-15. PMID:28138212

  3. A comparative study on liquid core formulation on the diameter on the alginate capsules

    NASA Astrophysics Data System (ADS)

    Ong, Hui-Yen; Lee, Boon-Beng; Radzi, AkmalHadi Ma'; Zakaria, Zarina; Chan, Eng-Seng

    2015-08-01

    Liquid core capsule has vast application in biotechnology related industries such as pharmaceutical, medical, agriculture and food. Formulation of different types of capsule was important to determine the performance of the capsule. Generally, the liquid core capsule with different formulations generated different size of capsule.Therefore, the aim of this project is to investigate the effect of different liquid core solution formulations on the diameter of capsule. The capsule produced by extruding liquid core solutions into sodium alginate solution. Three types of liquid core solutions (chitosan, xanthan gum, polyethylene glycol (PEG)) were investigated. The results showed that there is significant change in capsule diameter despite in different types of liquid core solution were used and a series of capsule range in diameter of 3.1 mm to 4.5 mm were produced. Alginate capsule with chitosan formulation appeared to be the largest capsule among all.

  4. Diameters and albedos of satellites of Uranus

    NASA Technical Reports Server (NTRS)

    Brown, R. H.; Cruikshank, D. P.; Morrison, D.

    1982-01-01

    Products of the masses of the five known satellites of Uranus, and estimates of their bulk densities and surface albedos, are used to infer their probable dimensions. Spectrophotometry has established the presence of water ice on the surfaces of all save Rhea, and the brightnesses of the satellites have been measured photoelectrically. The diameter measurements presented were made using a photometric/radiometric technique, whose recent recalibration, using independent solar system object measurements, has yielded absolute accuracies better than 5 per cent. The new albedo measurements show that Umbriel, Titania and Oberon are similar to the Jupiter moon Callisto, while Ariel resembles the Saturn moon Hyperion. The diameters of all four are similar to those of the large, icy Saturn satellites Rhea and Iapetus.

  5. Small diameter, deep bore optical inspection system

    DOEpatents

    Lord, David E.; Petrini, Richard R.; Carter, Gary W.

    1981-01-01

    An improved rod optic system for inspecting small diameter, deep bores. The system consists of a rod optic system utilizing a curved mirror at the end of the rod lens such that the optical path through the system is bent 90.degree. to minimize optical distortion in examining the sides of a curved bore. The system is particularly useful in the examination of small bores for corrosion, and is capable of examining 1/16 inch diameter and up to 4 inch deep drill holes, for example. The positioning of the curved mirror allows simultaneous viewing from shallow and right angle points of observation of the same artifact (such as corrosion) in the bore hole. The improved rod optic system may be used for direct eye sighting, or in combination with a still camera or a low-light television monitor; particularly low-light color television.

  6. Small diameter, deep bore optical inspection system

    DOEpatents

    Lord, D.E.; Petrini, R.R.; Carter, G.W.

    An improved rod optic system for inspecting small diameter, deep bores is described. The system consists of a rod optic system utilizing a curved mirror at the end of the rod lens such that the optical path through the system is bent 90/sup 0/ to minimize optical distortion in examing the sides of a curved bore. The system is particularly useful in the examination of small bores for corrosion, and is capable if examing 1/16 inch diameter and up to 4-inch deep drill holes, for example. The positioning of the curved mirror allows simultaneous viewing from shallow and righ angle points of observation of the same artifact (such as corrosion) in the bore hole. The improved rod optic system may be used for direct eye sighting, or in combination with a still camera or a low-light television monitor; particularly low-light color television.

  7. European Projects of Solar Diameter Monitoring

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino; Bianda, Michele; Arnaud, Jean

    2008-10-01

    Three projects dealing with solar diameter evolution are presently in development. Historical and contemporary eclipses and planetary transits data collection and analysis, to cover potentially the last 5 centuries with an accuracy of few hundreds of arcsecond on diameter's measurements. The French space mission PICARD with a few milliarcseconds accuray. With PICARD-SOL instruments located at the plateau of Calern the role of the atmosphere in ground-based measurements will be clarified. CLAVIUS is a Swiss-Italian project based on drift-scan method, free from optical distortions, where hourly circles transits will be monitored with fast CMOS sensors in different wavebands. The will run at IRSOL Gregory-Coudé telescope.

  8. On finding minimum-diameter clique trees

    SciTech Connect

    Blair, J.R.S. . Dept. of Computer Science); Peyton, B.W. )

    1991-08-01

    It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-diameter clique tree. The new algorithm is an analogue of the natural greedy algorithm for rooting an ordinary tree in order to minimize its height. It has potential application in the development of parallel algorithms for both knowledge-based systems and the solution of sparse linear systems of equations. 31 refs., 7 figs.

  9. Experimental study of lean flammability limits of methane/hydrogen/air mixtures in tubes of different diameters

    SciTech Connect

    Shoshin, Y.L.; Goey, L.P.H. de

    2010-04-15

    Lean limit flames in methane/hydrogen/air mixtures propagating in tubes of internal diameters (ID) of 6.0, 8.9, 12.3, 18.4, 25.2, 35.0, and 50.2 mm have been experimentally studied. The flames propagated upward from the open bottom end of the tube to the closed upper end. The content of hydrogen in the fuel gas has been varied in the range 0-40 mol%. Lean flammability limits have been determined; flame shapes recorded and the visible speed of flame propagation measured. Most of the observed limit flames in tubes with diameters in the range of 8.9-18.4 mm had enclosed shape, and could be characterized as distorted or spherical flame balls. The tendency was observed for mixtures with higher hydrogen content to form smaller size, more uniform flame balls in a wider range of tube diameters. At hydrogen content of 20% or more in the fuel gas, limit flames in largest diameters (35.0 mm and 50.2 mm ID) tubes had small, compared to the tube diameter, size and were ''lens''-shaped. ''Regular'' open-front lean limit flames were observed only for the smallest diameters (6.0 mm and 8.9 mm) and largest diameters (35.0 and 50.2 mm ID), and only for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures, except for 6 mm ID tube in which all limit flames had open front. In all experiments, except for the lean limit flames in methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures in the 8.9 mm ID tube, and all limit flames in 6.0 mm ID tube, visible flame speeds very weakly depended on the hydrogen content in the fuel gas and were close to- or below the theoretical estimate of the speed of a rising hot bubble. This observation suggests that the buoyancy is the major factor which determines the visible flame speed for studied limit flames, except that last mentioned. A decrease of the lean flammability limit value with decreasing the tube diameter was observed for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures for tubes having internal diameters in the range

  10. Quantification of pulmonary vessel diameter in low-dose CT images

    NASA Astrophysics Data System (ADS)

    Rudyanto, Rina D.; Ortiz de Solórzano, Carlos; Muñoz-Barrutia, Arrate

    2015-03-01

    Accurate quantification of vessel diameter in low-dose Computer Tomography (CT) images is important to study pulmonary diseases, in particular for the diagnosis of vascular diseases and the characterization of morphological vascular remodeling in Chronic Obstructive Pulmonary Disease (COPD). In this study, we objectively compare several vessel diameter estimation methods using a physical phantom. Five solid tubes of differing diameters (from 0.898 to 3.980 mm) were embedded in foam, simulating vessels in the lungs. To measure the diameters, we first extracted the vessels using either of two approaches: vessel enhancement using multi-scale Hessian matrix computation, or explicitly segmenting them using intensity threshold. We implemented six methods to quantify the diameter: three estimating diameter as a function of scale used to calculate the Hessian matrix; two calculating equivalent diameter from the crosssection area obtained by thresholding the intensity and vesselness response, respectively; and finally, estimating the diameter of the object using the Full Width Half Maximum (FWHM). We find that the accuracy of frequently used methods estimating vessel diameter from the multi-scale vesselness filter depends on the range and the number of scales used. Moreover, these methods still yield a significant error margin on the challenging estimation of the smallest diameter (on the order or below the size of the CT point spread function). Obviously, the performance of the thresholding-based methods depends on the value of the threshold. Finally, we observe that a simple adaptive thresholding approach can achieve a robust and accurate estimation of the smallest vessels diameter.

  11. Ultrasonic wave based pressure measurement in small diameter pipeline.

    PubMed

    Wang, Dan; Song, Zhengxiang; Wu, Yuan; Jiang, Yuan

    2015-12-01

    An effective non-intrusive method of ultrasound-based technique that allows monitoring liquid pressure in small diameter pipeline (less than 10mm) is presented in this paper. Ultrasonic wave could penetrate medium, through the acquisition of representative information from the echoes, properties of medium can be reflected. This pressure measurement is difficult due to that echoes' information is not easy to obtain in small diameter pipeline. The proposed method is a study on pipeline with Kneser liquid and is based on the principle that the transmission speed of ultrasonic wave in pipeline liquid correlates with liquid pressure and transmission speed of ultrasonic wave in pipeline liquid is reflected through ultrasonic propagation time providing that acoustic distance is fixed. Therefore, variation of ultrasonic propagation time can reflect variation of pressure in pipeline. Ultrasonic propagation time is obtained by electric processing approach and is accurately measured to nanosecond through high resolution time measurement module. We used ultrasonic propagation time difference to reflect actual pressure in this paper to reduce the environmental influences. The corresponding pressure values are finally obtained by acquiring the relationship between variation of ultrasonic propagation time difference and pressure with the use of neural network analysis method, the results show that this method is accurate and can be used in practice.

  12. Research on high accuracy diameter measurement system with CCD

    NASA Astrophysics Data System (ADS)

    Su, Bo; Duan, Guoteng

    2011-08-01

    Non-touch measurement is an important technology in many domains such as the monitoring of tool breakage and tool wear, et al. Based on the method of curve fitting and demanding inflection point, we present a high accuracy non-touch diameter measurement system. The measurement system comprise linear array CCD, CCD driving circuit, power supply, workseat, light source, data acquisition card and so on. The picture element of the linear array CCD is 2048, and the size of every pixel and the spacing of adjacent pixels have the same size of 14μmx14μm. The stabilized voltage supply has a constant voltage output of 3V. The light is generated by a halogen tungsten lamp, which does not represent any risk to the health of the whole system. The data acquisition card converts the analog signal to digital signal with the accuracy of 12 bit. The error of non-uniform of the CCD pixels in sensitivity and the electrical noise error are indicated in detail. The measurement system has a simple structure, high measuring precision, and can be carried out automatically. Experiment proves that the diameter measurement of the system is within the range of Φ0.5~Φ10mm, and the total measuring unstability of the system is within the range of +/- 1.4μm.

  13. New Large Diameter RF Complex Plasma Device

    NASA Astrophysics Data System (ADS)

    Meyer, John; Nosenko, Volodymyr; Thomas, Hubertus

    2016-10-01

    The Complex Plasma Research Group at the German Aerospace Center (DLR) in Oberpfaffenhofen has built a new large diameter rf plasma setup for dusty plasma experiments. The vacuum chamber is a stainless steel cylinder 0.90 m in diameter and 0.34 m in height with ports for viewing and measurement. A 0.85 m diameter plate in about the center serves as a powered electrode (13.56 MHz) with the chamber walls as the ground. It is pumped on by one of two Oerlikon turbo pumps with a pumping rate of 1100 l/s or 270 l/s. Argon gas is admitted into the chamber by an MKS mass flow meter and pumping is regulated by a butterfly valve to set pressure for experiments. A manual dropper is used to insert dust into the plasma. The dust is illuminated horizontally by a 660 nm 100 mW laser sheet and viewed from above by a Photron FASTCAM 1024 PCI camera. A vertical laser sheet of 635 nm will be used for side imaging. So far, single-layer plasma crystals of up to 15000 particles have been suspended. The particle velocity fluctuation spectra were measured and from these, the particle charge and screening length were calculated. Future experiments will explore the system-size dependence of the plasma crystal properties.

  14. Diameter-dependent hydrophobicity in carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Kyakuno, Haruka; Fukasawa, Mamoru; Ichimura, Ryota; Matsuda, Kazuyuki; Nakai, Yusuke; Miyata, Yasumitsu; Saito, Takeshi; Maniwa, Yutaka

    2016-08-01

    Single-wall carbon nanotubes (SWCNTs) are a good model system that provides atomically smooth nanocavities. It has been reported that water-SWCNTs exhibit hydrophobicity depending on the temperature T and the SWCNT diameter D. SWCNTs adsorb water molecules spontaneously in their cylindrical pores around room temperature, whereas they exhibit a hydrophilic-hydrophobic transition or wet-dry transition (WDT) at a critical temperature Twd ≈ 220-230 K and above a critical diameter Dc ≈ 1.4-1.6 nm. However, details of the WDT phenomenon and its mechanism remain unknown. Here, we report a systematic experimental study involving X-ray diffraction, optical microscopy, and differential scanning calorimetry. It is found that water molecules inside thick SWCNTs (D > Dc) evaporate and condense into ice Ih outside the SWCNTs at Twd upon cooling, and the ice Ih evaporates and condenses inside the SWCNTs upon heating. On the other hand, residual water trapped inside the SWCNTs below Twd freezes. Molecular dynamics simulations indicate that upon lowering T, the hydrophobicity of thick SWCNTs increases without any structural transition, while the water inside thin SWCNTs (D < Dc) exhibits a structural transition, forming an ordered ice. This ice has a well-developed hydrogen bonding network adapting to the cylindrical pores of the SWCNTs. Thus, the unusual diameter dependence of the WDT is attributed to the adaptability of the structure of water to the pore dimension and shape.

  15. Prediction of Stereochemistry using Q2MM

    PubMed Central

    2016-01-01

    Conspectus The standard method of screening ligands for selectivity in asymmetric, transition metal-catalyzed reactions requires experimental testing of hundreds of ligands from ligand libraries. This “trial and error” process is costly in terms of time as well as resources and, in general, is scientifically and intellectually unsatisfying as it reveals little about the underlying mechanism behind the selectivity. The accurate computational prediction of stereoselectivity in enantioselective catalysis requires adequate conformational sampling of the selectivity-determining transition state but has to be fast enough to compete with experimental screening techniques to be useful for the synthetic chemist. Although electronic structure calculations are accurate and general, they are too slow to allow for sampling or fast screening of ligand libraries. The combined requirements can be fulfilled by using appropriately fitted transition state force fields (TSFFs) that represent the transition state as a minimum and allow fast conformational sampling using Monte Carlo. Quantum-guided molecular mechanics (Q2MM) is an automated force field parametrization method that generates accurate, reaction-specific TSFFs by fitting the functional form of an arbitrary force field using only electronic structure calculations by minimization of an objective function. A key feature that distinguishes the Q2MM method from many other automated parametrization procedures is the use of the Hessian matrix in addition to geometric parameters and relative energies. This alleviates the known problems of overfitting of TSFFs. After validation of the TSFF by comparison to electronic structure results for a test set and available experimental data, the stereoselectivity of a reaction can be calculated by summation over the Boltzman-averaged relative energies of the conformations leading to the different stereoisomers. The Q2MM method has been applied successfully to perform virtual ligand

  16. Apollo 15 Index of 70 mm Photographs

    NASA Technical Reports Server (NTRS)

    1972-01-01

    All Apollo 15 70 mm photographs to which NASA photo numbers have been assigned are described in this index. In the first section all photographs are listed in sequence by NASA photo numbers. In subsequent sections, lunar surface and lunar orbital photographs are cross-indexed. Lunar surface photographs are listed in chronological order within the following categories: SEVA and LM window photos (LM window photos were taken before, between, and after EVA's), EVA 1, EVA 2, and EVA 3. Photographs of the lunar surface taken while in lunar orbit are cross-indexed by longitude in 10 deg increments, starting with the easternmost (farside) photos, and progressing to the westernmost (nearside) photos. Within each 10 deg interval of longitude, photographs are listed sequentially by NASA photo number, not by specific longitude of the principal point of each photograph.

  17. Prediction of Stereochemistry using Q2MM.

    PubMed

    Hansen, Eric; Rosales, Anthony R; Tutkowski, Brandon; Norrby, Per-Ola; Wiest, Olaf

    2016-05-17

    The standard method of screening ligands for selectivity in asymmetric, transition metal-catalyzed reactions requires experimental testing of hundreds of ligands from ligand libraries. This "trial and error" process is costly in terms of time as well as resources and, in general, is scientifically and intellectually unsatisfying as it reveals little about the underlying mechanism behind the selectivity. The accurate computational prediction of stereoselectivity in enantioselective catalysis requires adequate conformational sampling of the selectivity-determining transition state but has to be fast enough to compete with experimental screening techniques to be useful for the synthetic chemist. Although electronic structure calculations are accurate and general, they are too slow to allow for sampling or fast screening of ligand libraries. The combined requirements can be fulfilled by using appropriately fitted transition state force fields (TSFFs) that represent the transition state as a minimum and allow fast conformational sampling using Monte Carlo. Quantum-guided molecular mechanics (Q2MM) is an automated force field parametrization method that generates accurate, reaction-specific TSFFs by fitting the functional form of an arbitrary force field using only electronic structure calculations by minimization of an objective function. A key feature that distinguishes the Q2MM method from many other automated parametrization procedures is the use of the Hessian matrix in addition to geometric parameters and relative energies. This alleviates the known problems of overfitting of TSFFs. After validation of the TSFF by comparison to electronic structure results for a test set and available experimental data, the stereoselectivity of a reaction can be calculated by summation over the Boltzman-averaged relative energies of the conformations leading to the different stereoisomers. The Q2MM method has been applied successfully to perform virtual ligand screens on a range of

  18. 76 FR 7815 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF COMMERCE International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure... certain large diameter carbon and alloy seamless standard, line, and pressure pipe (over 4\\1/2\\...

  19. 75 FR 38781 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe From Japan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe From Japan: Rescission of... diameter carbon and alloy seamless standard, line, and pressure pipe from Japan. The review covers four... order on carbon and alloy seamless standard, line, and pressure pipe (over 4\\1/ 2\\ inches) from...

  20. Biomechanical analysis of the effects of implant diameter and bone quality in short implants placed in the atrophic posterior maxilla.

    PubMed

    Chang, Shih-Hao; Lin, Chun-Li; Hsue, Shue-Sang; Lin, Yang-Sung; Huang, Shiang-Rung

    2012-03-01

    Short dental implant (SDI) placement has been proposed as an alternative to reduce the surgical risks related to the advanced grafting procedures. The aim of this study was to simulate the biomechanical behaviors and influences of SDI diameters under various conditions of bone quality by using a validated finite element (FE) model for simulation. The CT image and CAD system were combined to construct the FE models with 6 mm length SDIs for 6, 7 and 8 mm diameters under three types of bone qualities, from normal to osteoporotic. The simulated results showed that implant diameter did not influence the von Mises strains of bone under the vertical load. The bone strains increased about 58.58% in the bone of least density under lateral load. Lateral loads induced high bone strain and implant stress than vertical loads. The bone strains of 7 mm- and 8 mm-diameter short implants were not different, and both were about 52% and 66% compared to those of 6 mm-wide short implant under lateral loads. The von Mises stress of the SDIs and their compartments were all less than the yield stress of the material under vertical and lateral loads. SDIs with diameter of 7 mm or above may have better mechanical transmission in the same length at feasible condition. Attaining a proper occlusal scheme design or selective occlusal adjustments to reduce the lateral occlusal force upon the SDIs is recommended.

  1. Three-dimensional relationship between high-order root-mean-square wavefront error, pupil diameter, and aging

    PubMed Central

    Applegate, Raymond A.; Donnelly, William J.; Marsack, Jason D.; Koenig, Darren E.; Pesudovs, Konrad

    2007-01-01

    We report root-mean-square (RMS) wavefront error (WFE) for individual aberrations and cumulative high-order (HO) RMS WFE for the normal human eye as a function of age by decade and pupil diameter in 1 mm steps from 3 to 7 mm and determine the relationship among HO RMS WFE, mean age for each decade of life, and luminance for physiologic pupil diameters. Subjects included 146 healthy individuals from 20 to 80 years of age. Ocular aberration was measured on the preferred eye of each subject (for a total of 146 eyes through dilated pupils; computed for 3, 4, 5, 6, and 7 mm pupils; and described with a tenth-radial-order normalized Zernike expansion. We found that HO RMS WFE increases faster with increasing pupil diameter for any given age and pupil diameter than it does with increasing age alone. A planar function accounts for 99% of the variance in the 3-D space defined by mean log HO RMS WFE, mean age for each decade of life, and pupil diameter. When physiologic pupil diameters are used to estimate HO RMS WFE as a function of luminance and age, at low luminance (9 cd/m2) HO RMS WFE decreases with increasing age. This normative data set details (1) the 3-D relationship between HO RMS WFE and age for fixed pupil diameters and (2) the 3-D relationship among HO RMS WFE, age, and luminance for physiologic pupil diameters. PMID:17301847

  2. Effect of fiber diameter and matrix alloys on impact-resistant boron/aluminum composites

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Signorelli, R. A.

    1976-01-01

    Efforts to improve the impact resistance of B/Al are reviewed and analyzed. Nonstandard thin-sheet charpy and Izod impact tests and standard full-size Charpy impact tests were conducted on composites containing unidirectional 0.10mm, 0.14mm, and 0.20mm diameter boron fibers in 1100, 2024, 5052, and 6061 Al matrices. Impact failure modes of B/Al are proposed in an attempt to describe the mechanisms involved and to provide insight for maximizing impact resistance. The impact strength of B/Al was significantly increased by proper selection of materials and processing. The use of a ductile matrix and large diameter boron fibers gave the highest impact strengths. This combination resulted in improved energy absorption through matrix shear deformation and multiple fiber breakage.

  3. Extra-pleuric coaxial system for CT-guided percutaneous fine-needle aspiration biopsy (FNAB) of small (≤20 mm) lung nodules: a novel technique using multiplanar reconstruction (MPR) images.

    PubMed

    Capasso, Raffaella; Nizzoli, Rita; Tiseo, Marcello; Pedrazzi, Giuseppe; Brunese, Luca; Rotondo, Antonio; De Filippo, Massimo

    2017-02-01

    The aim of the study is to present the diagnostic feasibility, usefulness, and safety of a novel technique for coaxial CT-guided fine-needle aspiration biopsy of small (≤20 mm in diameter) lung nodules. A 18-gauge (G) (1.2 × 40 mm) needle is inserted through the skin in the depth of the thoracic wall tissues remaining outside the pleura. Its positioning is planned and adjusted using multiplanar reconstruction (MPR) images along the 18-G guide needle axis tracing a reference outline extended from the needle tip to the target nodule. When the insertion of the 18-G extra-pleuric needle (EPN) proves to be precise, a 22-G Chiba needle is then passed through the outer 18-G EPN until it reaches the thoracic lesion for the sampling procedure. Patient population included 153 males and 94 females, with a mean age of 61.3 ± 21.6 years. Mean nodule diameter was 14.1 ± 2.2 mm. The lesion depth from pleural plane ranged from 0 mm to 127 mm. An average of 1.29 aspirates were performed per lesion. The most common complication was pneumothorax in 27 cases; there were no cases of PNX requiring chest tube insertion. Intrapulmonary bleeding along the needle track was observed in 32 patients. Exploiting the advantage of MPR images, our novel technique of extra-pleuric coaxial system with a 18-G EPN allows the operator to multiple samplings of small (≤20 mm) target lesions in various locations with a thinner (22-G Chiba) needle, thus reducing the degree of pleural, parenchymal, or adjacent organs damage.

  4. Hypervelocity impact on brittle materials of semi-infinite thickness: fracture morphology related to projectile diameter

    NASA Astrophysics Data System (ADS)

    Taylor, Emma A.; Kay, Laurie; Shrine, Nick R. G.

    Hypervelocity impact on brittle materials produces features not observed on ductile targets. Low fracture toughness and high yield strength produce a range of fracture morphologies including cracking, spallation and shatter. For sub-mm diameter projectiles, impact features are characterised by petaloid spallation separated by radial cracks. The conchoidal or spallation diameter is a parameter in current cratering equations. An alternative method for interpreting hypervelocity impacts on glass targets of semi-infinite thickness is tested against impact data produced using the Light Gas Gun (LGG) facility at the University of Kent at Canterbury (UKC), U.K. Spherical projectiles of glass and other materials with diameters 30-300 μm were fired at ~5 km s^-1 at a glass target of semi-infinite thickness. The data is used to test a power law relationship between projectile diameter and crack length. The results of this work are compared with published cratering/spallation equations for brittle materials.

  5. Measurement of anterior chamber diameter and biometry of anterior segment by Scheimpflug slitlamp photography

    SciTech Connect

    Lerman, S.; Hockwin, O.

    1985-03-01

    Twenty-eight fresh donor eyes (Georgia Lions Eye Bank) ranging in age from four months to 87 years were used for an in vitro study to determine the feasibility of obtaining accurate anterior chamber diameter measurements with our Scheimpflug ultraviolet-visible slitlamp densitography apparatus. The in vivo study was performed on 16 hybrid monkeys (of varying age). These data were within 0.1 mm of measurements obtained with a modified paracentesis needle specially designed to obtain such measurements. The results of the foregoing study demonstrate that the Scheimpflug slitlamp photographic analyses can provide an accurate measurement of the anterior chamber diameter without entering the globe surgically. This will enable the surgeon to determine the diameter and order an anterior chamber IOL of a specified size prior to surgery. The authors have devised an automated program to analyze the negatives and provide direct anterior chamber diameter measurements.

  6. Evaluation of design parameters of dental implant shape, diameter and length on stress distribution: a finite element analysis.

    PubMed

    Mohammed Ibrahim, M; Thulasingam, C; Nasser, K S G A; Balaji, V; Rajakumar, M; Rupkumar, P

    2011-09-01

    The aim was to evaluate the design parameters of dental implants shape, diameter and length on stress distribution by finite element analysis (FEA).The objectives of the study was to compare the influence of stress distribution in the implants of screw-vent tapered and parallel design by varying the implant diameter with a standard implant length. Six dental implant models have been simulated three-dimensionally. The influence of diameter and length on stress distribution was evaluated by Group I: for screw-vent tapered design (Zimmer Dental Implant Carlsbad, CA, USA) (1) Dental implant model with diameter 3.7 mm and length 13 mm. (2) Dental implant model with diameter 4.1 mm and length 13 mm. (3) Dental implant model with diameter 4.7 mm and length 13 mm. Group II: for parallel design (Zimmer Dental Implant Carlsbad, CA, USA) (4) Dental implant model with diameter 3.7 mm and length 13 mm. (5) Dental implant model with diameter 4.1 mm and length 13 mm. (6) Dental implant model with diameter 4.7 mm and length 13 mm. The 3-D model of the implant was created in the pro-e wildfire 4.0 software by giving various commands. This model was imported to the ANSYS software through IGES (initial graphic exchange specification) file for further analysis. All six models were loaded with a force of 17.1, 114.6 and 23.4 N in a lingual, an axial and disto-mesial direction respectively, simulating average masticatory force in a natural oblique direction, to analyze the stress distribution on these implants. The increase in implant diameter in Group I and Group II from 3.7 to 4.1 mm and from 4.1 to 4.7 mm with constant 13 mm length for screw-vent tapered and parallel design implant resulted in a reduction in maximum value of Von Mises stress in the bone surrounding the implant was statistically significant at 5% level done by student "t" test. The overall maximum value of Von Mises stress was decreased in parallel design implant diameter of 4.7 mm with constant

  7. Anisodamine accelerates spontaneous passage of single symptomatic bile duct stones ≤ 10 mm

    PubMed Central

    Gao, Jun; Ding, Xue-Mei; Ke, Shan; Zhou, Yi-Ming; Qian, Xiao-Jun; Ma, Rui-Liang; Ning, Chun-Min; Xin, Zong-Hai; Sun, Wen-Bing

    2013-01-01

    AIM: To investigate the rate of spontaneous passage of single and symptomatic common bile duct (CBD) stones ≤ 10 mm in diameter in 4 wk with or without a 2-wk course of anisodamine. METHODS: A multicenter, randomized, placebo-controlled trial was undertaken. A total of 197 patients who met the inclusion criteria were enrolled. Ninety-seven patients were assigned randomly to the control group and the other 100 to the anisodamine group. The anisodamine group received intravenous infusions of anisodamine (10 mg every 8 h) for 2 wk. The control group received the same volume of 0.9% isotonic saline for 2 wk. Patients underwent imaging studies and liver-function tests every week for 4 wk. The rate of spontaneous passage of CBD stones was analyzed. RESULTS: The rate of spontaneous passage of CBD stones was significantly higher in the anisodamine group than that in the control group (47.0% vs 22.7%). Most (87.2%, 41/47) stone passages in the anisodamine group occurred in the first 2 wk, and passages in the control group occurred at a comparable rate each week. Factors significantly increasing the possibility of spontaneous passage by univariate logistic regression analyses were stone diameter (< 5 mm vs ≥ 5 mm and ≤ 10 mm) and anisodamine therapy. Multivariate logistic regression analyses revealed that these two factors were significantly associated with spontaneous passage. CONCLUSION: Two weeks of anisodamine administration can safely accelerate spontaneous passage of single and symptomatic CBD stones ≤ 10 mm in diameter, especially for stones < 5 mm. PMID:24151390

  8. Variable diameter wind turbine rotor blades

    DOEpatents

    Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

    2005-12-06

    A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

  9. The diameter and albedo of 1943 Anteros

    NASA Technical Reports Server (NTRS)

    Veeder, G. J.; Tedesco, E. F.; Tholen, D. J.; Tokunaga, A.; Matthews, K.; Neugebauer, G.; Soifer, B. T.; Kowal, C.

    1981-01-01

    The results of broadband visual and infrared photometry of the Apollo-Amor asteroid 1943 Anteros during its 1980 apparition are reported. By means of a radiometric model, a diameter of 2.3 + or - 0.2 km and a visual geometric albedo of 0.13 + or - 0.03 is calculated. The albedo and reflectance spectrum of Anteros imply that it is a type S asteroid. Thus, Anteros may have a silicate surface similar to other Apollo-Amor asteroids as well as some stony-iron meteorites.

  10. A Variable Diameter Short Haul Civil Tiltrotor

    NASA Technical Reports Server (NTRS)

    Wang, James M.; Jones, Christopher T.; Nixon, Mark W.

    1999-01-01

    The Short-Haul-Civil-tiltrotor (SHCT) component of the NASA Aviation System Capacity Program is an effort to develop the technologies needed for a potential 40-passenger civil tiltrotor. The variable diameter tiltrotor (VDTR) is a Sikorsky concept aimed at improving tiltrotor hover and cruise performance currently limited by disk loading that is much higher in hover than conventional helicopter, and much lower in cruise than turbo-prop systems. This paper describes the technical merits of using a VDTR on a SHCT aircraft. The focus will be the rotor design.

  11. A 30-cm diameter argon ion source

    NASA Technical Reports Server (NTRS)

    Sovey, J. S.

    1976-01-01

    A 30 cm diameter argon ion source was evaluated. Ion source beam currents up to 4a were extracted with ion energies ranging from 0.2 to 1.5 KeV. An ion optics scaling relation was developed for predicting ion beam extraction capability as a function of total extraction voltage, gas type, and screen grid open area. Ignition and emission characteristics of several hollow cathode geometries were assessed for purposes of defining discharge chamber and neutralizer cathodes. Also presented are ion beam profile characteristics which exhibit broad beam capability well suited for ion beam sputtering applications.

  12. Thread gauge for measuring thread pitch diameters

    DOEpatents

    Brewster, A.L.

    1985-11-19

    A thread gauge which attaches to a vernier caliper to measure the thread pitch diameter of both externally threaded and internally threaded parts is disclosed. A pair of anvils are externally threaded with threads having the same pitch as those of the threaded part. Each anvil is mounted on a stem having a ball on which the anvil can rotate to properly mate with the parts to which the anvils are applied. The stems are detachably secured to the caliper blades by attachment collars having keyhole openings for receiving the stems and caliper blades. A set screw is used to secure each collar on its caliper blade. 2 figs.

  13. Thread gauge for measuring thread pitch diameters

    DOEpatents

    Brewster, Albert L.

    1985-01-01

    A thread gauge which attaches to a vernier caliper to measure the thread pitch diameter of both externally threaded and internally threaded parts. A pair of anvils are externally threaded with threads having the same pitch as those of the threaded part. Each anvil is mounted on a stem having a ball on which the anvil can rotate to properly mate with the parts to which the anvils are applied. The stems are detachably secured to the caliper blades by attachment collars having keyhole openings for receiving the stems and caliper blades. A set screw is used to secure each collar on its caliper blade.

  14. Effect of sympathetic tone on pressure-diameter relation of rabbit mesenteric veins in situ.

    PubMed

    Ozono, K; Bosnjak, Z J; Kampine, J P

    1991-03-01

    Although venous capacitance has been studied in the neurally isolated tissue or in the in vitro vein segment, this is the first study of sympathetic regulation of the pressure-diameter relation in mesenteric veins in situ, where innervation is kept intact. In 25 alpha-chloralose-anesthetized rabbits, mesenteric vein diameter (679 +/- 27 microns, ranges of 380-1,050 microns at initial state) and intravenous pressure were measured continuously at the same site by using videomicrometer and micropressure systems. Intravenous pressure was increased in a stepwise fashion from the baseline of 6-9 mm Hg to approximately 10, approximately 13, approximately 16, approximately 19, and occasionally to approximately 22 or approximately 26 mm Hg by occluding the portal vein with a pneumatic occluder. Each intravenous pressure was maintained for 90-120 seconds or 4-5 minutes until the diameter increase reached a plateau. Pressure-diameter curves were generated for the control state, during celiac ganglion stimulation, and during local tetrodotoxin or intravenous hexamethonium administration. Diameter was plotted as a function of pressure, and the curves were nonlinear or sigmoid. These results are different from the linear or curvilinear characteristics of the pressure-diameter or pressure-volume relation observed in the pharmacologically or chemically denervated preparation. Tetrodotoxin and hexamethonium attenuated the sigmoid shape of the pressure-diameter curve and shifted it toward the diameter axis of the curve. On the other hand, celiac ganglion stimulation did not change the sigmoid nature of the curve but shifted the curve toward the volume axis.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Low-Friction Minilaparoscopy Outperforms Regular 5-mm and 3-mm Instruments for Precise Tasks

    PubMed Central

    Firme, Wood A.; Lima, Diego L.; de Paula Lopes, Vladmir Goldstein; Montandon, Isabelle D.; Filho, Flavio Santos; Shadduck, Phillip P.

    2015-01-01

    Background and Objectives: Therapeutic laparoscopy was incorporated into surgical practice more than 25 y ago. Several modifications have since been developed to further minimize surgical trauma and improve results. Minilaparoscopy, performed with 2- to 3-mm instruments was introduced in the mid 1990s but failed to attain mainstream use, mostly because of the limitations of the early devices. Buoyed by a renewed interest, new generations of mini instruments are being developed with improved functionality and durability. This study is an objective evaluation of a new set of mini instruments with a novel low-friction design. Method: Twenty-two medical students and 22 surgical residents served as study participants. Three designs of laparoscopic instruments were evaluated: conventional 5 mm, traditional 3 mm, and low-friction 3 mm. The instruments were evaluated with a standard surgical simulator, emulating 4 exercises of various complexities, testing grasping, precise 2-handed movements, and suturing. The metric measured was time to task completion, with 5 replicates for every combination of instrument–exercise–participant. Results: For all 4 tasks, the instrument design that performed the best was the same in both the medical student and surgical resident groups. For the gross-grasping task, the 5-mm conventional instruments performed best, followed by the low-friction mini instruments. For the 3 more complex and precise tasks, the low-friction mini instruments outperformed both of the other instrument designs. Conclusion: In standard surgical simulator exercises, low-friction minilaparoscopic instruments outperformed both conventional 3- and 5-mm laparoscopic instruments for precise tasks. PMID:26390530

  16. Generation of Bessel Beams at mm- and Sub mm-wavelengths by Binary Optical Elements

    NASA Astrophysics Data System (ADS)

    Yu, Y. Z.; Dou, W. B.

    2008-07-01

    In this paper, binary optical elements (BOE’s) are designed for generating Bessel beams at mm- and sub mm- wavelengths. The design tool is to combine a genetic algorithm (GA) for global optimization with a two-dimension finite-difference time-domain (2-D FDTD) method for rigorous electromagnetic computation. The design process for converting a normally incident Gaussian beam into a Bessel beam is described in detail. Numerical results demonstrate that the designed BOE’s can not only successfully produce arbitrary order Bessel beams, but also have higher diffraction efficiencies when compared with amplitude holograms.

  17. Cold-electron bolometers for future mm and sub-mm sky surveys

    NASA Astrophysics Data System (ADS)

    Salatino, Maria; de Bernardis, Paolo; Mahashabde, Sumedh; Kuzmin, Leonid S.; Masi, Silvia

    2014-07-01

    Future sky surveys in the mm/sub-mm range, like the forthcoming balloon-borne missions LSPE, OLIMPO, SPIDER etc., will need detectors insensitive to cosmic rays (CRs) and with a NEP of the order of 10-17 ¥ 10-18 W/sqrt(Hz). The Cold-Electron Bolometers (CEBs) technology is promising, having the required proper- ties, since the absorber volume is extremely small and the electron system of the absorber is thermally insulated from the phonon system. We have developed an experimental setup to test the optical performance and the CRs insensitivity of CEBs, with the target of integrating them in the OLIMPO and LSPE focal planes.

  18. Measurement of Diameter Changes during Irradiation Testing

    SciTech Connect

    Davis, K. L.; Knudson, D. L.; Crepeau, J. C.; Solstad, S.

    2015-03-01

    New materials are being considered for fuel, cladding, and structures in advanced and existing nuclear reactors. Such materials can experience significant dimensional and physical changes during irradiation. Currently in the US, such changes are measured by repeatedly irradiating a specimen for a specified period of time and then removing it from the reactor for evaluation. The time and labor to remove, examine, and return irradiated samples for each measurement makes this approach very expensive. In addition, such techniques provide limited data and handling may disturb the phenomena of interest. In-pile detection of changes in geometry is sorely needed to understand real-time behavior during irradiation testing of fuels and materials in high flux US Material and Test Reactors (MTRs). This paper presents development results of an advanced Linear Variable Differential Transformer-based test rig capable of detecting real-time changes in diameter of fuel rods or material samples during irradiation in US MTRs. This test rig is being developed at the Idaho National Laboratory and will provide experimenters with a unique capability to measure diameter changes associated with fuel and cladding swelling, pellet-clad interaction, and crud buildup.

  19. Side Elevation, End Elevation, Cross Section, 1/2 Roof Plan, 1/2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Side Elevation, End Elevation, Cross Section, 1/2 Roof Plan, 1/2 Reflected Plan, 1/2 Floor Plan, 1/2 Reflected Plan - Jack's Mill Covered Bridge, Spanning Henderson Creek, Oquawka, Henderson County, IL

  20. Influence of Implant Design (Cylindrical and Conical) in the Load Transfer Surrounding Long (13mm) and Short (7mm) Length Implants: A Photoelastic Analysis

    PubMed Central

    Gehrke, Sergio Alexandre; Frugis, Victor Lourenço; Shibli, Jamil Awad; Fernandez, Maria Piedad Ramirez; Sánchez de Val, José Eduardo Maté; Girardo, José Luis Calvo; Taschieri, Silvio; Corbella, Stefano

    2016-01-01

    Purpose: This study compared the influence of implant design (cylindrical and conical) in the load transfer on bone surrounding 13mm and 7mm length implants under simulated occlusal loading, using photoelastic analysis. Method: Dental implants of 4mm diameter were divided into four groups, which varied in length and design: Group 1- standard (13 mm) cylindrical implant; Group 2 - standard conical implant; Group 3 – short (7 mm) cylindrical implant, and Group 4 - short conical implant. After the inclusion of the implant models in a photoelastic resin, they were subjected to a static load of 100 N. The lengths of the fringes that were generated were measured in three portions since the implants body: crestal, central and apical portion, parallel to the implant long axis. Furthermore, the entire extension area of dissipation of force was measured. Data were analyzed by one-way ANOVA (α = 0.05). Results: Lower stress was observed at the crestal bone in groups 2 and 4, while the stress levels in groups 1 and 3 were higher with significant differences compared to the other groups (p<0.05). Conclusion: The total amount of stress transmitted to the bone was not affected by implant length under axial loading condition, but changed in relation to the implant design with respect to the concentration of the fringes, which corresponded to the load distribution, with even more dissipation by conical implants. PMID:27843505

  1. Estimating the magnus moment effect on stability of 30-mm boomed projectiles

    NASA Astrophysics Data System (ADS)

    Byers, R. H.; Cobb, K.

    1985-08-01

    This report documents the results obtained from a comparison of free-flight spark range tests and PRODASMAGNUS computer stability results for 30mm spin stabilized projectiles. Two configurations were considered, each with the same boom diameter of 0.5, 1.0 inch and 1.25 inch boom lengths. The results show that PRODASMAGNUS can accurately predict the effects of a boom's presence on projectile stability.

  2. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are required to obtain a title V permit. 63.1(b)(3) Record of the applicability determination No All affected... applicability of each paragraph of subpart A of this part to sources subject to subpart MM. 63.1(c)(2) Title...

  3. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are required to obtain a title V permit. 63.1(b)(3) Record of the applicability determination No All affected... applicability of each paragraph of subpart A of this part to sources subject to subpart MM. 63.1(c)(2) Title...

  4. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are required to obtain a title V permit. 63.1(b)(3) Record of the applicability determination No All affected... applicability of each paragraph of subpart A of this part to sources subject to subpart MM. 63.1(c)(2) Title...

  5. Diameter and position effect determination of diaphragm on hybrid rocket motor

    NASA Astrophysics Data System (ADS)

    Sun, Xingliang; Tian, Hui; Cai, Guobiao

    2016-09-01

    This study is aimed to determine and better reveal the mixture enhancement and regression rate distribution of hybrid rocket motor with diaphragm by numerical approach. A numerical model based on the computational fluid dynamics software is built to simulate the flow and combustion inside the motor. Four firing tests of the motor, including one without diaphragm and three with diaphragm, are conducted on a standard experimental system and also used as a reference for numerical simulation, the consistency between the simulation and experiment demonstrates that the numerical approach is an effective method to study the diaphragm effect on the motor performance. The flow field characteristic and regression rate distribution inside the hybrid rocket motor are then calculated to analyze the effect of position and diameter of the diaphragm. The results indicate that the diaphragm almost have no effect on the regression rate before it. However, the regression rate after the diaphragm has a strong dependence on the position and diameter of the diaphragm. As the diameter decreases and the position moves backward, the regression rate increases larger and larger, this is mainly due to the augmentation of the eddy generated by the diaphragm, which enhances the heat feedback transferred to the grain surface. When the diameter of diaphragm located at middle of grain decreases from 50 mm to 20 mm, regression rate is increased from 0.30 mm/s to 0.57 mm/s. The use of the diaphragm does cause a combustion efficiency improvement; the maximum combustion efficiency is enhanced to 98.9% from lower than 90% of the motor with no diaphragm. The increasing amplitude displays a square relation with the diameter decrease, since the entrainment of the eddy make the reactants mix sufficiently to release more energy inside the motor.

  6. Impact of doping and diameter on the electrical properties of GaSb nanowires

    NASA Astrophysics Data System (ADS)

    Babadi, Aein S.; Svensson, Johannes; Lind, Erik; Wernersson, Lars-Erik

    2017-01-01

    The effect of doping and diameter on the electrical properties of vapor-liquid-solid grown GaSb nanowires was characterized using long channel back-gated lateral transistors and top-gated devices. The measurements showed that increasing the doping concentration significantly increases the conductivity while reducing the control over the channel potential and shifting the threshold voltage, as expected. The highest average mobility was 85 cm2/V.s measured for an unintentionally doped GaSb nanowire with a diameter of 45 nm, whereas medium doped nanowires with large diameters (81 nm) showed a value of 153 cm2/V.s. The mobility is found to be independent of nanowire diameter in the range of 36 nm-68 nm, while the resistivity is strongly reduced with increasing diameter attributed to the surface depletion of charge carriers. The data are in good agreement with an analytical calculation of the depletion depth. A high transconductance was achieved by scaling down the channel length to 200 nm, reaching a maximum value of 80 μS/μm for a top-gated GaSb nanowires transistor with an ON-resistance of 26 kΩ corresponding to 3.9 Ω.mm. The lowest contact resistance obtained was 0.35 Ω.mm for transistors with the highest doping concentration.

  7. Effect of Orifice Diameter on Bubble Generation Process in Melt Gas Injection to Prepare Aluminum Foams

    NASA Astrophysics Data System (ADS)

    Yuan, Jianyu; Li, Yanxiang; Wang, Ningzhen; Cheng, Ying; Chen, Xiang

    2016-06-01

    The bubble generation process in conditioned A356 alloy melt through submerged spiry orifices with a wide diameter range (from 0.07 to 1.0 mm) is investigated in order to prepare aluminum foams with fine pores. The gas flow rate and chamber pressure relationship for each orifice is first determined when blowing gas in atmospheric environment. The effects of chamber pressure ( P c) and orifice diameter ( D o) on bubble size are then analyzed separately when blowing gas in melt. A three-dimensional fitting curve is obtained illustrating both the influences of orifice diameter and chamber pressure on bubble size based on the experimental data. It is found that the bubble size has a V-shaped relationship with orifice diameter and chamber pressure neighboring the optimized parameter ( D o = 0.25 mm, P c = 0.4 MPa). The bubble generation mechanism is proposed based on the Rayleigh-Plesset equation. It is found that the bubbles will not be generated until a threshold pressure difference is reached. The threshold pressure difference is dependent on the orifice diameter, which determines the time span of pre-formation stage and bubble growth stage.

  8. PHOS Experiment: Thermal Response of a Large Diameter Pulsating Heat Pipe on Board REXUS-18 Rocket

    NASA Astrophysics Data System (ADS)

    Creatini, F.; Guidi, G. M.; Belfi, F.; Cicero, G.; Fioriti, D.; Di Prizio, D.; Piacquadio, S.; Becatti, G.; Orlandini, G.; Frigerio, A.; Fontanesi, S.; Nannipieri, P.; Rognini, M.; Morganti, N.; Filippeschi, S.; Di Marco, P.; Fanucci, L.; Baronti, F.; Mameli, M.; Marengo, M.; Manzoni, M.

    2015-09-01

    In the present work, the results of two Closed Loop Pulsating Heat Pipes (CLPHPs) tested on board REXUS-1 8 sounding rocket in order to get experimental data over a relatively broad reduced gravity period (about 90 s) are thoroughly discussed. The CLPHPs are partially filled with refrigerant FC-72 and have, respectively, an inner tube diameter larger (3 .0 mm) and slightly smaller (1 .6 mm) than a critical diameter defined on Earth gravity conditions. On ground, the small diameter CLPHP works as a real Pulsating Heat Pipe (PHP): the typical capillary slug flow pattern forms inside the device and the heat exchange is triggered by self-sustained thermally driven oscillations of the working fluid. Conversely, the large diameter CLPHP behaves like a two-phase thermosyphon in vertical position while does not operate in horizontal position as the working fluid stratifies within the tube and surface tension is not able to balance buoyancy. Then, the idea to test the CLPHPs under reduced gravity conditions: as soon as gravity reduces, buoyancy becomes less intense and the typical capillary slug flow pattern can also forms within a tube with a larger diameter. Moreover, this allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience the expected reduced gravity conditions due to a failure of the yo-yo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described.

  9. Physical parameters of very small diameter 10 MV X-ray beams for linac-based stereotactic radiosurgery

    NASA Astrophysics Data System (ADS)

    Sham, Edwin

    Physical aspects of very small diameter X-ray beams used for a linac-based stereotactic radiosurgery are presented in this thesis. A 10 MV linac was used as the radiation source. Very small 10 MV photon fields with diameters of 1.5 mm, 3 mm, and 5 mm are produced by special collimators attached to the treatment head of the linac. The radiation beam data were measured with a small field diode detector as well as radiographic and radiochromic films. Measured beam parameters were compared with the same parameters calculated with Monte Carlo (MC) simulations. For very small photon fields with diameters on the order of the focal spot size, MC calculations show that both the percentage depth dose (PDD) distributions and dose profiles are sensitive to the focal spot size. A simple sliding slit technique was developed to measure the focal spot size and shape for accurate MC simulations of very small diameter beams. The measured focal spot of the 10 MV linac is elliptical in shape and fitted by a Gaussian distribution with full-widths-at-half-maximum (FWHMs) of 2.05 mm and 1.34 mm in the principal axes of the ellipse. A Gaussian circle equivalent in area to the experimentally determined focal spot ellipse was used in MC simulations. The resulting PDD and beam profile calculations are in good agreement with the measurements. Dynamic radiosurgery with very small diameter photon beams was carried out using the 10 MV linac. Radiosurgical isodose distributions were measured with radiographic films in a spherical head phantom and calculated with the MC technique. A good agreement between the measured and MC-calculated isodose distributions for very small diameter fields is achieved. The displacement of the center of the measured isodose distributions relative to the laser-defined isocenter was on the order of 0.7 mm. All these results show the potential of linac-based radiosurgery with very small diameter photon beams for clinical use.

  10. Large Diameter Limbs for Dilated Common Iliac Arteries in Endovascular Aneurysm Repair. Is It Safe?

    SciTech Connect

    Malagari, Katerina Brountzos, Elias; Gougoulakis, Alexandros; Papathanasiou, Matilda; Alexopoulou, Efthymia; Mastorakou, Renata; Kelekis, Dimitris

    2004-09-15

    In this prospective study we examined whether dilated common iliac arteries (CIAs) can provide a safe distal seal in endovascular aneurysm repair (EVAR) with the use of bifurcated stent grafts with large diameter limbs. Sixteen patients with 26 dilated CIAs with a diameter of {>=}6 mm who were offered EVAR using stent grafts with large diameter limbs were included in the study (Group A). Forty-two patients who also underwent EVAR without iliac dilatation, matched for age, sex and surgical risk were used for comparison (controls-Group B). In group A mean CIA diameter was 18.2 mm (16-28) and mean abdominal aortic aneurysm (AAA) diameter was 6.87 {+-} 1.05 cm; mean age was 77.2 {+-} 4.8 yrs (67-81). Mean follow-up was 33.6 months (2.8 yrs). CIA diameter changes and development of endoleaks were assessed by CT angiography (CTA). Overall iliac dilatation was present in 16/58 of our patients (27.6%). In 10 patients dilatation was bilateral (17.3%). Partial or complete flow to the internal iliac artery (IIA) territories was preserved in all patients post-EVAR. On follow-up, stable caliber of the dilated CIAs was observed in 21 patients (84%), enlargement of 1mm in 3 (16%), and failure of the distal attachment in 1 (6.2%). Compared to the control group there was no statistical significance in the incidence of complications. Dilated common iliac arteries provide a safe distal seal in patients who have undergone EVAR, thus obviating the need for additional endovascular procedures and sparing flow in the IIA vascular bed.

  11. Glial Cell Contribution to Basal Vessel Diameter and Pressure-Initiated Vascular Responses in Rat Retina

    PubMed Central

    Li, Hui; Bui, Bang V.; Cull, Grant; Wang, Fang; Wang, Lin

    2017-01-01

    Purpose The purpose of this study was to test the hypothesis that retinal glial cells modify basal vessel diameter and pressure-initiated vascular regulation in rat retina. Methods In rats, L-2-aminoadipic acid (LAA, 10 nM) was intravitreally injected to inhibit glial cell activity. Twenty-four hours following injection, retinal glial intracellular calcium (Ca2+) was labeled with the fluorescent calcium indicator Fluo-4/AM (F4, 1 mM). At 110 minutes after injection, intraocular pressure (IOP) was elevated from 20 to 50 mm Hg. Prior to and during IOP elevation, Ca2+ and retinal vessel diameter were assessed using a spectral-domain optical coherence tomography/confocal scanning laser ophthalmoscope. Dynamic changes in Ca2+ and diameter from IOP elevation were quantified. The response in LAA-treated eyes was compared with vehicle treated control eyes. Results L-2-Aminoadipic acid treatment significantly reduced F4-positive cells in the retina (LAA, 16 ± 20 vs. control, 55 ± 37 cells/mm2; P = 0.02). Twenty-four hours following LAA treatment, basal venous diameter was increased from 38.9 ± 3.9 to 51.8 ± 6.4 μm (P < 0.0001, n = 20), whereas arterial diameter was unchanged (from 30.3 ± 3.5 to 30.7 ± 2.8 μm; P = 0.64). In response to IOP elevation, LAA-treated eyes showed a smaller increase in glial cell Ca2+ around both arteries and veins in comparison with control (P < 0.001 for both). There was also significantly greater IOP-induced vasoconstriction in both vessel types (P = 0.05 and P = 0.02, respectively; n = 6 each). Conclusions The results suggest that glial cells can modulate basal retinal venous diameter and contribute to pressure-initiated vascular responses. PMID:28055098

  12. An interferometric Abbe-type comparator for the calibration of internal and external diameter standards

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Ahn; Kim, Jae Wan; Kang, Chu-Shik; Eom, Tae Bong

    2010-07-01

    We developed an Abbe-type comparator using a laser interferometer and a linear variable differential transformer (LVDT) probe as displacement sensors, which can measure the diameter of ring and plug gauges up to 300 mm. The measurement system is configured according to the Abbe principle, and consists of translation stages, a laser interferometer, an LVDT probe and an electronic controller. The main translation stage is made by using a precision ceramic guide and air bearing pads, and is driven by a backlash-free lead screw and a micro-stepping motor. The laser interferometer measures the displacement of a moving mirror aligned with the probe coaxially. The environmental effect is corrected automatically during the measurement. The effective diameter of the probe ball is calibrated using a reference gauge block. The performance of each component was evaluated through experiments and the measurement uncertainty of the overall system was analyzed. We measured three diameter artifacts, which are 11.95 mm and 100 mm ring gauges and a 98.5 mm plug gauge, and compared the measured values with the calibrated ones. They were consistent with each other within 0.3 µm, which is less than the expanded measurement uncertainty (k = 2).

  13. Development of fine diameter mullite fiber

    NASA Technical Reports Server (NTRS)

    Long, W. G.

    1974-01-01

    Results are presented of a program to develop and evaluate mullite fiber with a mean diameter under two microns. The two micron fiber is produced by a blowing process at room temperature from a low viscosity (10-25 poise) solution. The blown fiber was evaluated for dimensional stability in thermal cycling to 1371 C, and was equivalent to the 5 micron spun B and W mullite fiber. An additive study was conducted to evaluate substitutes for the boron. Three levels of chromium, lithium fluoride, and magnesium were added to the standard composition in place of boron and the fiber produced was evaluated for chemical and dimensional stability in thermal cycling to 1371 C. The magnesium was the most chemically stable, but the chrome additive imparted the best dimensional stability.

  14. Thirty-centimeter-diameter ion milling source

    NASA Technical Reports Server (NTRS)

    Robinson, R. S.

    1978-01-01

    A 30-cm beam diameter ion source has been designed and fabricated for micromachining and sputtering applications. An argon ion current density of 1 mA/cu cm at 500 eV ion energy was selected as a design operating condition. The completed ion source met the design criteria at this operating condition with a uniform and well-collimated beam having an average variation in current density of + or - 5% over the center of 20 cm of the beam. This ion source has a multipole magnetic field that employs permanent magnets between permeable pole pieces. Langmuir probe surveys of the source plasma support the design concepts of a multipole field and a circumferential cathode to enhance plasma uniformity.

  15. Fire protection covering for small diameter missiles

    NASA Technical Reports Server (NTRS)

    Riccitiello, S. R.; Sawko, P. M. (Inventor)

    1979-01-01

    Flexible intumescent protection sheeting of unusually uniform thickness were prepared from epoxy-polysulfide compositions, containing microfibers and the ammonium salt of 1,4-nitroaniline-2-sulfonic acid, as disclosed in U.S. Pat. No. 3,663,464, except that an ammonium salt particle size in the order of 5 to 8 microns and a fiber size of about 1/128th inch in length and 3 to 5 microns in diameter were found critical to obtain the required density of 1.46 to 1.50 g/cc. The insulation sheeting was prepared by a continuous process involving vacuum mixing, calendering, and curing under very strict conditions which depend to some extent upon the thickness of the sheet produced.

  16. Defining the role of TORC1/2 in multiple myeloma

    PubMed Central

    Maiso, Patricia; Liu, Yi; Morgan, Brittany; Azab, Abdel Kareem; Ren, Pingda; Martin, Michel B.; Zhang, Yong; Liu, Yang; Sacco, Antonio; Ngo, Hai; Azab, Feda; Quang, Phong; Rodig, Scott J.; Lin, Charles P.; Roccaro, Aldo M.; Rommel, Christian

    2011-01-01

    Mammalian target of rapamycin (mTOR) is a downstream serine/threonine kinase of the PI3K/Akt pathway that integrates signals from the tumor microenvironment to regulate multiple cellular processes. Rapamycin and its analogs have not shown significant activity in multiple myeloma (MM), likely because of the lack of inhibition of TORC2. In the present study, we investigated the baseline activity of the PI3K/Akt/mTOR pathway TORC1/2 in MM cell lines with different genetic abnormalities. TORC1/2 knock-down led to significant inhibition of the proliferation of MM cells, even in the presence of BM stromal cells. We also tested INK128, a dual TORC1/2 inhibitor, as a new therapeutic agent against these MM cell lines. We showed that dual TORC1/2 inhibition is much more active than TORC1 inhibition alone (rapamycin), even in the presence of cytokines or stromal cells. In vitro and in vivo studies showed that p-4EBP1 and p-Akt inhibition could be predictive markers of TORC2 inhibition in MM cell lines. Dual TORC1/2 inhibition showed better inhibition of adhesion to BM microenvironmental cells and inhibition of homing in vivo. These studies form the basis for further clinical testing of TORC1/2 inhibitors in MM. PMID:22045983

  17. 76 FR 66688 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-27

    ... International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure... seamless standard, line, and pressure pipe (over 4 \\1/2\\ inches) from Japan. The review covers four... carbon and alloy seamless standard, line, and pressure pipe (over 4\\1/2\\ inches) from Japan for...

  18. 77 FR 27428 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-10

    ... International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure..., line, and pressure pipe (over 4\\1/2\\ inches) from Japan. The review covers four manufacturers/exporters... alloy seamless standard, line, and pressure pipe (over 4\\1/2\\ inches) from Japan for the period June...

  19. Sampling efficiency of modified 37-mm sampling cassettes using computational fluid dynamics.

    PubMed

    Anthony, T Renée; Sleeth, Darrah; Volckens, John

    2016-01-01

    In the U.S., most industrial hygiene practitioners continue to rely on the closed-face cassette (CFC) to assess worker exposures to hazardous dusts, primarily because ease of use, cost, and familiarity. However, mass concentrations measured with this classic sampler underestimate exposures to larger particles throughout the inhalable particulate mass (IPM) size range (up to aerodynamic diameters of 100 μm). To investigate whether the current 37-mm inlet cap can be redesigned to better meet the IPM sampling criterion, computational fluid dynamics (CFD) models were developed, and particle sampling efficiencies associated with various modifications to the CFC inlet cap were determined. Simulations of fluid flow (standard k-epsilon turbulent model) and particle transport (laminar trajectories, 1-116 μm) were conducted using sampling flow rates of 10 L min(-1) in slow moving air (0.2 m s(-1)) in the facing-the-wind orientation. Combinations of seven inlet shapes and three inlet diameters were evaluated as candidates to replace the current 37-mm inlet cap. For a given inlet geometry, differences in sampler efficiency between inlet diameters averaged less than 1% for particles through 100 μm, but the largest opening was found to increase the efficiency for the 116 μm particles by 14% for the flat inlet cap. A substantial reduction in sampler efficiency was identified for sampler inlets with side walls extending beyond the dimension of the external lip of the current 37-mm CFC. The inlet cap based on the 37-mm CFC dimensions with an expanded 15-mm entry provided the best agreement with facing-the-wind human aspiration efficiency. The sampler efficiency was increased with a flat entry or with a thin central lip adjacent to the new enlarged entry. This work provides a substantial body of sampling efficiency estimates as a function of particle size and inlet geometry for personal aerosol samplers.

  20. The influence of nerve conduits diameter in motor nerve recovery after segmental nerve repair.

    PubMed

    Giusti, Guilherme; Shin, Richard H; Lee, Joo-Yup; Mattar, Tiago G; Bishop, Allen T; Shin, Alexander Y

    2014-11-01

    Many conduits have demonstrated potential to substitute nerve autografts; however, the influence of conduit inner diameter (ID) has never been studied as a separate parameter. This experimental study compared motor recovery after segmental nerve repair with two different ID collagen conduits: 1.5 and 2.0 mm. In addition, the conduits were analyzed in vitro to determine the variations of ID before and after hydration. Thirty rats were divided into three groups: 2.0 mm ID, 1.5 mm ID, and a control group autograft. After 12 weeks, the 1.5 mm ID group demonstrated significant increase in force (P < 0.0001) and weight (P < 0.0001) of the tibialis anterior muscle and better histomorphometry results of the peroneal nerve (P < 0.05) compared to 2.0 mm ID group; nevertheless, autograft results outperformed both conduits (P < 0.0001). Conduits ID were somewhat smaller than advertised, measuring 1.59 ± 0.03 mm and 1.25 ± 0.0 mm. Only the larger conduit showed a 6% increase in ID after hydration, changing to 1.69 ± 0.02 mm. Although autografts perform best, an improvement in motor recovery can be achieved with collagen conduits when a better size match conduit is being used. Minimal changes in collagen conduits ID can be expected after implantation.

  1. Influence of focal spot on characteristics of very small diameter radiosurgical beams.

    PubMed

    Sham, Edwin; Seuntjens, Jan; Devic, Slobodan; Podgorsak, Ervin B

    2008-07-01

    Percentage depth dose (PDD) distributions and beam profiles of very small diameter (1.5-5 mm) megavoltage radiosurgical beams calculated with Monte Carlo (MC) technique critically depend on the diameter of the circular focal spot used in the simulation: The smaller is the field diameter, the larger is the effect. Thus, in simulations of radiosurgical fields that have diameters of the order of the focal spot size, an accurate focal spot geometry should be used. We used a simplified moving slit technique in conjunction with a diode detector for evaluation of the focal spot size and shape of a megavoltage 6 MV linac as well as for determination of the equivalent focal spot diameter of the linac for use in MC simulations. The measured total diode signal contains three components: A direct focal spot signal, a background signal, and an extra-focal radiation signal. A single profile scan of the focal spot signal is Gaussian like in shape, and its full width at half maximum is used to define the focal spot dimension for this scan. The focal spot of our 6 MV linac is approximated with a Gaussian circle, and when the geometry of the effective focal spot circle is used in MC simulations, the agreement between MC-calculated and measured PDD distributions as well as beam profiles is good even for radiosurgical fields as small as 1.5 mm in diameter. Our results also confirm that matching the penumbral areas of accurately measured large-field beam profiles to the same areas of the MC-calculated beam profiles reliably leads to a realistic effective focal spot size for use in MC simulations of very small diameter beams.

  2. 7 CFR 1.2 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Policy. 1.2 Section 1.2 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Official Records § 1.2 Policy. (a) Agencies of USDA shall comply with the time limits set forth in the FOIA and in this subpart for responding to...

  3. 29 CFR 1.2 - Definitions. 1

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 1 2012-07-01 2012-07-01 false Definitions. 1 1.2 Section 1.2 Labor Office of the Secretary of Labor PROCEDURES FOR PREDETERMINATION OF WAGE RATES § 1.2 Definitions. 1 1 These definitions... Assistance Act of 1972. (e) The term Wage Determinations OnLine (WDOL) shall mean the Government Internet...

  4. 29 CFR 1.2 - Definitions. 1

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 1 2014-07-01 2013-07-01 true Definitions. 1 1.2 Section 1.2 Labor Office of the Secretary of Labor PROCEDURES FOR PREDETERMINATION OF WAGE RATES § 1.2 Definitions. 1 1 These definitions are... Assistance Act of 1972. (e) The term Wage Determinations OnLine (WDOL) shall mean the Government Internet...

  5. 29 CFR 1.2 - Definitions. 1

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 1 2011-07-01 2011-07-01 false Definitions. 1 1.2 Section 1.2 Labor Office of the Secretary of Labor PROCEDURES FOR PREDETERMINATION OF WAGE RATES § 1.2 Definitions. 1 1 These definitions... Assistance Act of 1972. (e) The term Wage Determinations OnLine (WDOL) shall mean the Government Internet...

  6. 29 CFR 1.2 - Definitions. 1

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 1 2013-07-01 2013-07-01 false Definitions. 1 1.2 Section 1.2 Labor Office of the Secretary of Labor PROCEDURES FOR PREDETERMINATION OF WAGE RATES § 1.2 Definitions. 1 1 These definitions... Assistance Act of 1972. (e) The term Wage Determinations OnLine (WDOL) shall mean the Government Internet...

  7. 11 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Definitions. 1.2 Section 1.2 Federal Elections FEDERAL ELECTION COMMISSION PRIVACY ACT § 1.2 Definitions. As defined in the Privacy Act of 1974 and for the purposes of this part, unless otherwise required by the context, the following terms shall...

  8. 45 CFR 1210.1-2 - Scope.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Scope. 1210.1-2 Section 1210.1-2 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE VISTA TRAINEE DESELECTION AND VOLUNTEER EARLY TERMINATION PROCEDURES General § 1210.1-2 Scope. (a) This part applies to all Trainees and...

  9. 45 CFR 1211.1-2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Applicability. 1211.1-2 Section 1211.1-2 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE VOLUNTEER GRIEVANCE PROCEDURES § 1211.1-2 Applicability. This part applies to all volunteers enrolled under part A of title I of the...

  10. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2010 CFR

    2006-10-01

    ... 43 Public Lands: Interior 2 2006-10-01 2006-10-01 false Contents. 2812.1-2 Section 2812.1-2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT... Bay Revested Lands § 2812.1-2 Contents. (a) An individual applicant and each member of...

  11. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2010 CFR

    1997-10-01

    ... 43 Public Lands: Interior 2 1997-10-01 1997-10-01 false Contents. 2812.1-2 Section 2812.1-2 LAND RESOURCE MANAGEMENT (2000) TRAMROADS AND LOGGING ROADS Over O. and C. and Coos Bay Revested Lands § 2812.1-2 Contents. (a) An individual applicant and each member of any unincorporated association which...

  12. Attached cavitation at a small diameter ultrasonic horn tip

    NASA Astrophysics Data System (ADS)

    Žnidarčič, Anton; Mettin, Robert; Cairós, Carlos; Dular, Matevž

    2014-02-01

    Ultrasonic horn transducers are frequently used in applications of acoustic cavitation in liquids, for instance, for cell disruption or sonochemical reactions. They are operated typically in the frequency range up to about 50 kHz and have tip diameters from some mm to several cm. It has been observed that if the horn tip is sufficiently small and driven at high amplitude, cavitation is very strong, and the tip can be covered entirely by the gas/vapor phase for longer time intervals. A peculiar dynamics of the attached cavity can emerge with expansion and collapse at a self-generated frequency in the subharmonic range, i.e., below the acoustic driving frequency. Here, we present a systematic study of the cavitation dynamics in water at a 20 kHz horn tip of 3 mm diameter. The system was investigated by high-speed imaging with simultaneous recording of the acoustic emissions. Measurements were performed under variation of acoustic power, air saturation, viscosity, surface tension, and temperature of the liquid. Our findings show that the liquid properties play no significant role in the dynamics of the attached cavitation at the small ultrasonic horn. Also the variation of the experimental geometry, within a certain range, did not change the dynamics. We believe that the main two reasons for the peculiar dynamics of cavitation on a small ultrasonic horn are the higher energy density on a small tip and the inability of the big tip to "wash" away the gaseous bubbles. Calculation of the somewhat adapted Strouhal number revealed that, similar to the hydrodynamic cavitation, values which are relatively low characterize slow cavitation structure dynamics. In cases where the cavitation follows the driving frequency this value lies much higher - probably at Str > 20. In the spirit to distinguish the observed phenomenon with other cavitation dynamics at ultrasonic transducer surfaces, we suggest to term the observed phenomenon of attached cavities partly covering the full horn

  13. MASTER: a radiometer for mm and sub-mm observations from the Antarctic Plateau

    NASA Astrophysics Data System (ADS)

    Boella, G.; Gervasi, M.; Passerini, A.; Sironi, G.; Tartari, A.; Zannoni, M.; Natale, V.

    A radiometer based on SIS mixers for astrophysical observations is being assembled. The system, cooled to cryogenic temperature by a pulse tube refrigerator, is intended for operation on the Antartic Plateau during the local winter, using the mm dishes available there in the future. The system prototype will be tested at the focus of the 2.6m MITO telescope at the Testa Grigia Observatory on the italian Alps. We discuss the system characteristics and the observational programs.

  14. Perch diameter and branching patterns have interactive effects on the locomotion and path choice of anole lizards.

    PubMed

    Jones, Zachary M; Jayne, Bruce C

    2012-06-15

    Natural branches vary conspicuously in their diameter, density and orientation, but how these latter two factors affect animal locomotion is poorly understood. Thus, for three species of arboreal anole lizards found on different size branches and with different limb lengths, we tested sprinting performance on cylinders with five diameters (5-100 mm) and five patterns of pegs, which simulated different branch orientations and spacing. We also tested whether the lizards preferred surfaces that enhanced their performance. The overall responses to different surfaces were similar among the three species, although the magnitude of the effects differed. All species were faster on cylinders with larger diameter and no pegs along the top. The short-limbed species was the slowest on all surfaces. Much of the variation in performance resulted from variable amounts of pausing among different surfaces and species. Lizards preferred to run along the top of cylinders, but pegs along the top of the narrow cylinders interfered with this. Pegs on top of the 100-mm diameter cylinder, however, had little effect on speed as the lizards ran quite a straight path alongside pegs without bumping into them. All three species usually chose surfaces with greater diameters and fewer pegs, but very large diameters with pegs were preferred to much smaller diameter cylinders without pegs. Our results suggest that preferring larger diameters in natural vegetation has a direct benefit for speed and an added benefit of allowing detouring around branches with little adverse effect on speed.

  15. System performance advances of 18-mm and 16-mm subminiature image intensifier sensors

    NASA Astrophysics Data System (ADS)

    Thomas, Nils I.

    2000-11-01

    Night vision system design has been centered aroudn the An/AVS-6 and AN/PVS-7 night vision goggle systems for the past 20 years. Goggle performance has improved during this time through increased performance of the image intensifier sensor, primarily the Omni IV sensor from ITT Industries Night Vision. Most of this improvement has been at the optimal light level (1E-3 fc scene illumination). Recent advances in image sensor performance from the filmless Generation (Gen) IV sensors has increased the low light level performance of night vision devices from 0.3 cy/mr to 0.7 cy/mr. In addition, sensor packaging design requirements have forced night vision sensor manufactures to design light weight, small volume sensors. ITT recently has designed such a sensor in a 16-mm format. This sensor if 50% lighter, up to 50% shorter, and has design features that simplify the objective lens design. New night vision goggles have been, and are being, designed which reduce the perceived head-supported weight. This paper presents signal-to-noise ratio, halo, and other film-less sensor data and similar 16-mm subminiature sensor data. The resulting system performance data will be described. Finally, the system design improvements and relationships with the subminiature 16-mm subminiature sensor will be given.

  16. A 12-mm carcinoid tumor of the minor duodenal papilla with lymph node metastases.

    PubMed

    Fukami, Yasuyuki; Kurumiya, Yasuhiro; Mizuno, Keisuke; Sekoguchi, Ei; Kobayashi, Satoshi; Ito, Akira; Tomida, Akihiro; Onishi, Sakura; Shirotsuki, Ryo; Okubo, Kenji; Narita, Michihiko

    2013-01-01

    Carcinoid tumors located in the minor duodenal papilla are extremely rare, with only a few cases reported in the literature. Herein, we report the case of a 71-year-old man with a 12-mm carcinoid tumor at the minor duodenal papilla with lymph node metastases. Multidetector-row computed tomography with contrast enhancement revealed a 12-mm well-enhanced tumor in the duodenum. Upper gastrointestinal endoscopy showed a 12-mm submucosal tumor at the minor papilla of the duodenum. Biopsy specimens revealed a carcinoid tumor, and a subtotal stomach-preserving pancreatoduodenectomy was performed. Carcinoid tumors at the minor duodenal papilla have a high prevalence of nodal disease, even for tumors <2 cm in diameter. Therefore, we believe that radical resection with tumor-free margins (i.e. pancreatoduodenectomy) is the treatment of choice.

  17. Development of large diameter carbon monofilament

    NASA Technical Reports Server (NTRS)

    Jacob, B.; Neltri, R. D.

    1973-01-01

    A process for preparing large diameter carbon-boron monofilament was developed. The process involves chemical vapor depositing a carbon-boron alloy monofilament from a BCl3, CH4, and H2 gas mixture onto a carbon substrate. Amorphous alloys were formed when gaseous mixtures containing greater than 20 percent methane (80 percent BCl3) were used. The longest uninterrupted lengths of carbon-boron monofilament were produced using a CH4/BCl3 gas ratio of 2.34. It was found that the properties of the carbon-boron alloy monofilament improved when the carbon substrate was precleaned in chlorine. The highest strength monofilament was attained when a CH4/BCl3 gas volume ratio of 0.44 was 28 million N/sq cm (40 million psi). While the highest strengths were attained in this run, the 0.44 gas ratio and other CH4/BCl3 ratios less than 2.34 would not yield long runs. Runs using these ratios were usually terminated because of a break in the monofilament within the reactor. It is felt better process control could probably be achieved by varying the amount of hydrogen; the BCl3/H2 ratio was kept constant in these studies.

  18. The 15 cm diameter ion thruster research

    NASA Technical Reports Server (NTRS)

    Wilbur, P. J.

    1974-01-01

    The startup reliability of a 15 cm diameter mercury bombardment ion thruster which employs a pulsed high voltage tickler electrode on the main and neutralizer cathodes is examined. Startup of the thruster is achieved 100% of the time on the main cathode and 98.7% of the time on the neutralizer cathode over a 3640 cycle test. The thruster was started from a 20 C initial condition and operated for an hour at a 600 mA beam current. An energy efficiency of 75% and a propellant utilization efficiency of 77% was achieved over the complete cycle. The effect of a single cusp magnetic field thruster length on its performance is discussed. Guidelines are formulated for the shaping of magnetic field lines in thrusters. A model describing double ion production in mercury discharges is presented. The production route is shown to occur through the single ionic ground state. Photographs of the interior of an operating-hollow cathode are presented. A cathode spot is shown to be present if the cathode is free of low work-function surfaces. The spot is observed if a low work-function oxide coating is applied to the cathode insert. Results show that low work-function oxide coatings tend to migrate during thruster operation.

  19. What benefit could be derived from on-line adaptive prostate radiotherapy using rectal diameter as a predictor of motion?

    PubMed Central

    Oates, Richard; Gill, Suki; Foroudi, Farshad; Joon, Michael Lim; Schneider, Michal; Bressel, Mathias; Kron, Tomas

    2015-01-01

    This study investigated a relationship between rectum diameter and prostate motion during treatment with a view to reducing planning target volume (PTV) margins for an adaptive protocol. One hundred and ninety-four cone-beam computed tomography (CBCT) images of 10 patients were used to relate rectum diameter on CBCT to prostate intrafraction displacement. A threshold rectum diameter was used to model the impact of an adaptive PTV margin on rectum and bladder dose. Potential dose escalation with a 6 mm uniform margin adaptive protocol was compared to a PTV margin of 10 mm expansion of the clinical target volume (CTV) except 6 mm posterior. Of 194 fractions, 104 had a maximum rectal diameter of ≤3.5 cm. The prostate displaced ≤4 mm in 102 of those fractions. Changing from a standard to an adaptive PTV margin reduced the volume of rectum receiving 25, 50, 60, and 70 Gy by around 12, 9, 10, and 16%, respectively and bladder by approximately 21, 27, 29, and 35%, respectively. An average dose escalation of 4.2 Gy may be possible with an adaptive prostate radiotherapy protocol. In conclusion, a relationship between the prostate motion and the diameter of the rectum on CBCT potentially could enable daily adaptive radiotherapy which can be implemented from the first fraction. PMID:26150683

  20. Behavior of large diameter wire ropes

    SciTech Connect

    Raoof, M.; Kraincanic, I.

    1995-12-31

    The paper reviews the recent theoretical work of the present authors as regards the prediction of the 2 {times} 2 stiffness matrix describing axial/torsional coupling of large diameter wire ropes. The theoretical analysis is based on results from a previously reported orthotropic sheet model which enables one to obtain estimates of the coefficients in the 2 {times} 2 stiffness matrix describing the axial/torsional coupling of the constituent spiral strands. The proposed model can (unlike previously available theories for wire ropes) cater for the presence of interwire friction and the various wire rope stiffness coefficients corresponding to both no-slip and full-slip regimes can be calculated. The no-slip regime corresponds to cases when an axially preloaded wire rope experiences cyclic variations of external load which are small enough not to induce initiation of gross interwire slippage within the constituent spiral strands. For sufficiently large values of range/mean axial load ratios, on the other hand, gross interwire slippage takes place and the effects of interwire friction on wire rope stiffness coefficients will be negligibly small compared with the effects due to the force changes in the wires themselves. Theoretical models have been developed for two types of wire ropes, i.e., those with an independent wire rope core (IWRC) or the types with a fiber core: the salient features for both approaches are reviewed with an emphasis on the characteristics of various wire rope constructions. In addition, experimental results from other sources are found to provide encouraging support for the theoretical predictions in a number of areas.

  1. Mockup Small-Diameter Air Distribution System

    SciTech Connect

    A. Poerschke and A. Rudd

    2016-05-01

    This report investigates the feasibility of using a home-run manifold small-diameter duct system to provide space conditioning air to individual thermal zones in a low-load home. This compact layout allows duct systems to be brought easily within conditioned space via interior partition walls. Centrally locating the air hander unit in the house significantly reduces duct lengths. The plenum box is designed so that each connected duct receives an equal amount of airflow, regardless of the duct position on the box. Furthermore, within a reasonable set of length restrictions, each duct continues to receive similar airflow. The design method uses an additive approach to reach the total needed zonal airflow. Once the cubic feet per minute needed to satisfy the thermal load of a zone has been determined, the total number of duct runs to a zone can be calculated by dividing the required airflow by the standard airflow from each duct. The additive approach greatly simplifies the design effort and reduces the potential for duct design mistakes to be made. Measured results indicate that this plenum design can satisfy the heating load. However, the total airflow falls short of satisfying the cooling load in a hypothetical building. Static pressure inside the plenum box of 51.5 Pa limited the total airflow of the attached mini-split heat pump blower, thus limiting the total thermal capacity. Fan energy consumption is kept to 0.16 to 0.22 watt/CFM by using short duct runs and smooth duct material.

  2. The LLAMA 12 m mm/sub-mm radiotelescope in the Andes

    NASA Astrophysics Data System (ADS)

    Lepine, Jacques; Edemundo Arnal, Marcelo; de Graauw, Thijs; Abraham, Zulema; Gimenez de Castro, Guillermo; de Gouveia Dal Pino, Elisabete; Morras, Ricardo; Larrarte, Juan; Viramontes, José; Finger, Ricardo; Kooi, Jacob; Reeves, Rodrigo; Beaklini, Pedro

    2015-08-01

    LLAMA (Large Latin American Millimetric Array) is a joint Argentinean-Brazilian project of a 12m mm/sub-mm radio telescope similar to the APEX antenna, to be installed at a site at 4800 m altitude near San Antonio de Los Cobres in the Salta Province in Argentine, at 150 km from ALMA. The scientific cases for single dish and VLBI observations include black holes and accretion disks, the molecular evolution of interstellar clouds, the structure of the Galaxy, the formation of galaxies, and much more. The antenna was ordered to the company Vertex Antennentechnik in June 2014, and the construction is progressing quickly; it will be installed at the site in 2016. The radio telescope will be equipped with up to six receivers covering bands similar to those of ALMA. Cryostats with room for 3 cartridges, constructed by NAOJ (Tokyo,Japan), will be installed in each of the two Nasmyth cabins. Among the first receivers we will have an ALMA band 9 provided by NOVA (Groningen, Holland) and a band 5 from the Chalmers University (Sweden). Other receivers are still being discussed at the time of submission of this abstract,At high frequencies, VLBI observations at high frequencies could be made with ALMA, APEX and ASTE, and Northern radiotelescopes. In this way, LLAMA will be a seed for a Latin-American VLBI network.

  3. Estimation of local pulse wave velocity using arterial diameter waveforms: Experimental validation in sheep

    NASA Astrophysics Data System (ADS)

    Graf, S.; Craiem, D.; Barra, J. G.; Armentano, R. L.

    2011-12-01

    Increased arterial stiffness is associated with an increased risk of cardiovascular events. Estimation of arterial stiffness using local pulse wave velocity (PWV) promises to be very useful for noninvasive diagnosis of arteriosclerosis. In this work we estimated in an instrumented sheep, the local aortic pulse wave velocity using two sonomicrometry diameter sensors (separated 7.5 cm) according to the transit time method (PWVTT) with a sampling rate of 4 KHz. We simultaneously measured aortic pressure in order to determine from pressure-diameter loops (PWVPDLoop), the "true" local aortic pulse wave velocity. A pneumatic cuff occluder was implanted in the aorta in order to compare both methods under a wide range of pressure levels. Mean pressure values ranged from 47 to 101 mmHg and mean proximal diameter values from 12.5. to 15.2 mm. There were no significant differences between PWVTT and PWVPDLoop values (451±43 vs. 447±48 cm/s, p = ns, paired t-test). Both methods correlated significantly (R = 0.81, p<0.05). The mean difference between both methods was only -4±29 cm/s, whereas the range of the limits of agreement (mean ± 2 standard deviation) was -61 to +53 cm/s, showing no trend. In conclusion, the diameter waveforms transit time method was found to allow an accurate and precise estimation of the local aortic PWV.

  4. Influence of implant diameters on the integration of screw implants. An experimental study in rabbits.

    PubMed

    Ivanoff, C J; Sennerby, L; Johansson, C; Rangert, B; Lekholm, U

    1997-04-01

    The influence of diameter on the integration of titanium screw-shaped implants was studied in the rabbit tibia by means of removal torque measurements and histomorphometry. Implants 3.0, 3.75, 5.0, and 6.0 mm in diameter and 6.0 mm long were inserted through one cortical layer in the tibial metaphyses of nine rabbits and allowed to heal for 12 weeks. The implants were then unscrewed with a torque gauge, and the peak torque required to shear off the implants was recorded. The histologic analysis in undemineralized ground sections comprised (1) a gross description of the implant sites and assessments of (2) the total implant length in bone and (3) in the cortical passage, as well as (4) the thickness of the cortical bone adjacent to the implants. From the removal torque values obtained and morphometric measurements, a mean shear stress value was calculated for each implant type. The biomechanical tests showed a statistically significant increase of removal torque with increasing implant diameter. The resistance to shear seemed to be determined by the implant surface in supportive cortical bone, whereas the newly formed bone at the periosteal and endosteal surfaces did not seem to have any supportive properties after 12 weeks. It is suggested that wide diameter implants may be used clinically to increase implant stability.

  5. Research on the optimum length-diameter ratio of the charge of a multimode warhead

    NASA Astrophysics Data System (ADS)

    Li, Weibing; Wang, X.; Li, Wenbin; Zheng, Y.

    2012-05-01

    This paper outlines our research on a multimode warhead in which we adopted center point and annular initiation modes to form multimode penetrators. Using LS-DYNA software, we studied the effect of the configuration parameters, namely the length/diameter ratio of the shaped charge, on the formation parameters, such as the velocity and length/diameter ratio, of multimode penetrators. We found that when the charge length was in the range of 0.9-1.2 times the charge diameter, the same structure of shaped charge can form suitable multimode penetrators. Either an explosively formed penetrator (EFP) or a long stretchy rod-shaped EFP penetrator can be formed. We establish an optimum charge length for penetrator formation of 1.4 times the charge diameter. Simulation results were validated using X-ray imaging experiments and they were in good agreement. The results found that by increasing the charge length from 0.9 to 1.4 times the charge diameter, the penetration depth of the EFP increased by 74.5%, while increasing the charge length from 1.4 to 1.6 times the charge diameter only increased the penetration depth by 1.9%.

  6. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Contents. 2812.1-2 Section 2812.1-2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND RESOURCE MANAGEMENT (2000) TRAMROADS AND LOGGING ROADS Over O. and C. and Coos Bay Revested Lands § 2812.1-2 Contents. (a)...

  7. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Contents. 2812.1-2 Section 2812.1-2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND RESOURCE MANAGEMENT (2000) TRAMROADS AND LOGGING ROADS Over O. and C. and Coos Bay Revested Lands § 2812.1-2 Contents. (a)...

  8. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Contents. 2812.1-2 Section 2812.1-2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND RESOURCE MANAGEMENT (2000) TRAMROADS AND LOGGING ROADS Over O. and C. and Coos Bay Revested Lands § 2812.1-2 Contents. (a)...

  9. 43 CFR 2812.1-2 - Contents.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Contents. 2812.1-2 Section 2812.1-2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND RESOURCE MANAGEMENT (2000) TRAMROADS AND LOGGING ROADS Over O. and C. and Coos Bay Revested Lands § 2812.1-2 Contents. (a)...

  10. Optical design and evaluation of a 4 mm cost-effective ultra-high-definition arthroscope.

    PubMed

    Cheng, Dewen; Wang, Yongtian; Yu, Lu; Liu, Xiaohua

    2014-08-01

    High definition and magnification rigid endoscope plays an important role in modern minimally invasive medical surgery and diagnosis. In this paper, we present the design and evaluation methods of a high definition rigid endoscope, specifically an arthroscope, with a large depth of field (DOF). The incident heights and exit angles of the sampled rays on the relay lens are controlled during the optimization process to ensure an effective field view (70°) and a normal ray path within the limited lens diameter of 2.7 mm. The lens is set up as a multi-configuration system with two extreme and one middle object distances to cover a large DOF. As a result, an entrance pupil of 0.3 mm is achieved for the first time, to bring the theoretical resolution to 23.1 lps/mm in the object space at a working distance of 20 mm, with the wavelength of 0.532 um. The modulation transfer function (MTF) curves approach diffraction limit, and the values are all higher than 0.3 at 160 line pairs/mm (lps/mm) in the image space. Meanwhile, stray light caused by total internal reflection on the inner wall of the rod lenses and the objective lens is eliminated. The measured resolution in the object space at a 20 mm working distance is 22.3 lps/mm, and test results show that other performance characteristics also fulfill design requirements. The relay lenses are designed with only one type of the spacer and two types of lenses to greatly reduce the fabrication and assembly cost. The design method has important research and application values for lens systems used in modern minimally invasive medical surgery and industrial non-destructive testing area.

  11. Optical design and evaluation of a 4 mm cost-effective ultra-high-definition arthroscope

    PubMed Central

    Cheng, Dewen; Wang, Yongtian; Yu, Lu; Liu, Xiaohua

    2014-01-01

    High definition and magnification rigid endoscope plays an important role in modern minimally invasive medical surgery and diagnosis. In this paper, we present the design and evaluation methods of a high definition rigid endoscope, specifically an arthroscope, with a large depth of field (DOF). The incident heights and exit angles of the sampled rays on the relay lens are controlled during the optimization process to ensure an effective field view (70°) and a normal ray path within the limited lens diameter of 2.7 mm. The lens is set up as a multi-configuration system with two extreme and one middle object distances to cover a large DOF. As a result, an entrance pupil of 0.3 mm is achieved for the first time, to bring the theoretical resolution to 23.1 lps/mm in the object space at a working distance of 20 mm, with the wavelength of 0.532 um. The modulation transfer function (MTF) curves approach diffraction limit, and the values are all higher than 0.3 at 160 line pairs/mm (lps/mm) in the image space. Meanwhile, stray light caused by total internal reflection on the inner wall of the rod lenses and the objective lens is eliminated. The measured resolution in the object space at a 20 mm working distance is 22.3 lps/mm, and test results show that other performance characteristics also fulfill design requirements. The relay lenses are designed with only one type of the spacer and two types of lenses to greatly reduce the fabrication and assembly cost. The design method has important research and application values for lens systems used in modern minimally invasive medical surgery and industrial non-destructive testing area. PMID:25136495

  12. Instability of Reference Diameter in the Evaluation of Stenosis After Coronary Angioplasty: Percent Diameter Stenosis Overestimates Dilative Effects Due to Reference Diameter Reduction

    SciTech Connect

    Hirami, Ryouichi; Iwasaki, Kohichiro; Kusachi, Shozo; Murakami, Takashi; Hina, Kazuyoshi; Matano, Shigeru; Murakami, Masaaki; Kita, Toshimasa; Sakakibara, Noburu; Tsuji, Takao

    2000-03-15

    Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty.Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis.Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%).Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.

  13. Effect of ceramic membrane channel diameter on limiting retentate protein concentration during skim milk microfiltration.

    PubMed

    Adams, Michael C; Barbano, David M

    2016-01-01

    Our objective was to determine the effect of retentate flow channel diameter (4 or 6mm) of nongraded permeability 100-nm pore size ceramic membranes operated in nonuniform transmembrane pressure mode on the limiting retentate protein concentration (LRPC) while microfiltering (MF) skim milk at a temperature of 50°C, a flux of 55 kg · m(-2) · h(-1), and an average cross-flow velocity of 7 m · s(-1). At the above conditions, the retentate true protein concentration was incrementally increased from 7 to 11.5%. When temperature, flux, and average cross-flow velocity were controlled, ceramic membrane retentate flow channel diameter did not affect the LRPC. This indicates that LRPC is not a function of the Reynolds number. Computational fluid dynamics data, which indicated that both membranes had similar radial velocity profiles within their retentate flow channels, supported this finding. Membranes with 6-mm flow channels can be operated at a lower pressure decrease from membrane inlet to membrane outlet (ΔP) or at a higher cross-flow velocity, depending on which is controlled, than membranes with 4-mm flow channels. This implies that 6-mm membranes could achieve a higher LRPC than 4-mm membranes at the same ΔP due to an increase in cross-flow velocity. In theory, the higher LRPC of the 6-mm membranes could facilitate 95% serum protein removal in 2 MF stages with diafiltration between stages if no serum protein were rejected by the membrane. At the same flux, retentate protein concentration, and average cross-flow velocity, 4-mm membranes require 21% more energy to remove a given amount of permeate than 6-mm membranes, despite the lower surface area of the 6-mm membranes. Equations to predict skim milk MF retentate viscosity as a function of protein concentration and temperature are provided. Retentate viscosity, retentate recirculation pump frequency required to maintain a given cross-flow velocity at a given retentate viscosity, and retentate protein

  14. Teaching Evolutionary Mechanisms: Genetic Drift and M&M's.

    ERIC Educational Resources Information Center

    Staub, Nancy L.

    2002-01-01

    Describes a classroom activity that teaches the mechanism of genetic drift to undergraduates. Illustrates a number of concepts that are critical in developing evolution literacy by sampling M&M milk chocolate candies. (MM)

  15. Extrusion of small-diameter, thin-wall tungsten tubing

    NASA Technical Reports Server (NTRS)

    Blankenship, C. P.; Gyorgak, C. A.

    1967-01-01

    Small-diameter, thin-wall seamless tubing of tungsten has been fabricated in lengths of up to 10 feet by hot extrusion over a floating mandrel. Extrusion of 0.50-inch-diameter tubing over 0.4-inch-diameter mandrels was accomplished at temperatures ranging from 3000 degrees to 4000 degrees F.

  16. 44 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Definitions. 1.2 Section 1.2 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY... Emergency Management Agency. (e) Major rule means any regulation that is likely to result in: (1) An...

  17. 44 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Definitions. 1.2 Section 1.2 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY... Emergency Management Agency. (e) Major rule means any regulation that is likely to result in: (1) An...

  18. 24 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... participates in carrying out such program or activity (such as a redeveloper in the Urban Renewal Program... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Definitions. 1.2 Section 1.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban...

  19. 24 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... participates in carrying out such program or activity (such as a redeveloper in the Urban Renewal Program... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Definitions. 1.2 Section 1.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban...

  20. 24 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... participates in carrying out such program or activity (such as a redeveloper in the Urban Renewal Program... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Definitions. 1.2 Section 1.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban...

  1. 24 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... participates in carrying out such program or activity (such as a redeveloper in the Urban Renewal Program... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Definitions. 1.2 Section 1.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban...

  2. 24 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... participates in carrying out such program or activity (such as a redeveloper in the Urban Renewal Program... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Definitions. 1.2 Section 1.2 Housing and Urban Development Office of the Secretary, Department of Housing and Urban...

  3. 8 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Definitions. 1.2 Section 1.2 Aliens and... alien means an applicant for admission coming or attempting to come into the United States at a port-of-entry, or an alien seeking transit through the United States at a port-of-entry, or an alien...

  4. Presenting a high accuracy Theta-Phi-style fiber-positioner prototype with a 15-mm pitch

    NASA Astrophysics Data System (ADS)

    Haeuser, Marco; Lang-Bardl, Florian; Richter, Josef; Hess, Hans-Joachim; Degwert, Adrian; Karasz, Adolf; Kosyra, Ralf; Hopp, Ulrich; Bender, Ralf

    2014-07-01

    We present a Θ - Φ-style fiber-positioner prototype, which will be controlled via the EMI-robust CAN-Bus. Our positioner points without iterations or a metrology system. Due to the overlapping patrol disc of 17.3 mm diameter, we reach a filling factor of 100 %. The positioners diameter is 14.6 mm, containing the control electronics on a contemporary PCB of 13.5 mm width. While moving, the power consumption does not lead to a significant rise in temperature. Given a mechanical reference point measured by stall detection, the absolute accuracy is 27 μm (1σ = 14 µm) and pointings are repeatable with 7 μm (1σ = 4 μm). Better positioning may be reachable with upcoming calibration.

  5. Optimization of rod diameter in solid state lasers side pumped with multiple laser diode arrays

    NASA Technical Reports Server (NTRS)

    Sims, Newton, Jr.; Chamblee, Christyl M.; Barnes, Norman P.; Lockard, George E.; Cross, Patricia L.

    1992-01-01

    Results of a study to determine the optimum laser rod diameter for maximum output energy in a solid state neodymium laser transversely pumped with multiple laser diode arrays are reported here. Experiments were performed with 1.0 mm, 1.5 mm and 2.0 mm rod radii of both neodymium doped Y3Al5O12 (Nd:YAG) and La2Be2O5 (Nd:BeL) pumped with laser diode arrays having a maximum combined energy of 10.5 mJ. Equations were derived which predict the optimum rod radius and corresponding output mirror reflectivity for a given laser material and total pump energy. Predictions of the equations agreed well with the experiments for each of the laser materials which possessed significantly different laser properties from one another.

  6. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  7. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  8. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  9. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  10. Estimation of genetic parameters for wool fiber diameter measures.

    PubMed

    Iman, N Y; Johnson, C L; Russell, W C; Stobart, R H

    1992-04-01

    Genetic and phenotypic correlations and heritability estimates of side, britch, and core diameters; side and britch CV; side and britch diameter difference; and clean fleece weight were investigated using 385 western white-faced ewes produced by 50 sires and maintained at two locations on a selection study. Data were analyzed using analysis of variance procedures, and effects in the final model included breed of sire-selection line combination, sire within breed-selection line, and location. Heritabilities were estimated by paternal half-sib analysis. Sires within breed-selection line represented a significant source of variation for all traits studied. Location had a significant effect on side diameter, side and britch diameter difference, and clean fleece weight. Age of ewe only affected clean fleece weight. Phenotypic and genetic correlations among side, britch, and core diameter measures were high and positive. Phenotypic correlations ranged from .68 to .75 and genetic correlations ranged from .74 to .89. The genetic correlations between side and britch diameter difference and side diameter or core diameter were small (-.16 and .28, respectively). However, there was a stronger genetic correlation between side and britch diameter difference and britch diameter (.55). Heritability of the difference between side and britch diameter was high (.46 +/- .16) and similar to heritability estimates reported for other wool traits. Results of this study indicate that relatively rapid genetic progress through selection for fiber diameter should be possible. In addition, increased uniformity in fiber diameter should be possible through selection for either side and britch diameter difference or side or britch CV.

  11. Crown diameters of the deciduous teeth of Taiwanese.

    PubMed

    Liu, H H; Dung, S Z; Yang, Y H

    2000-06-01

    The purposes of this study were (1) to characterize the crown diameters of the deciduous teeth of Taiwanese; (2) to compare the differences in the deciduous crown diameters between different populations. The results might provide odontometric information in making preformed stainless steel crowns of the Chinese population. Study casts of 90 children (51 boys and 39 girls) of aged 3 to 6 years were used in this study. The maximum mesiodistal crown diameter (the greatest distance between the contact points of the approximal surfaces) and the buccolingual crown diameter (the greatest distance at a right angle to the mesiodistal measurement) were obtained by using an electronic digital caliper. Significant differences between antimeres were found in the mesiodistal diameters of maxillary canine and maxillary molars (p < 0.001) as well as in the buccolingual diameters of mandibular molars (p < 0.05). Excellent correlations between the antimeres of the corresponding teeth were found (r = 0.70 to 0.96). Boys generally had larger crown diameters than girls with the exception of mesiodistal diameters of maxillary and mandibular canines, and mandibular lateral incisor, whereas the statistically significant gender difference was only found in the buccolingual diameter of mandibular second molar (p < 0.05). The higher the percentage of sexual dimorphism, the larger the gender differences. The percentage of sexual dimorphism ranged from 0.09 to 1.94 for mesiodistal diameters and 0.04 to 2.86 for buccolingual diameters. The mandibular second molar was the most dimorphic tooth. Variations in the crown diameters of the deciduous teeth existed among and within different populations. Deciduous mesiodistal crown diameters of Taiwanese were, in general, smaller than those of Australian aborigines, Taiwan Chinese aborigines, and Hong Kong Chinese, but larger than those of American whites. When considering the buccolingual crown diameters, our data were significantly smaller than those

  12. Multiple Small Diameter Drillings Increase Femoral Neck Stability Compared with Single Large Diameter Femoral Head Core Decompression Technique for Avascular Necrosis of the Femoral Head.

    PubMed

    Brown, Philip J; Mannava, Sandeep; Seyler, Thorsten M; Plate, Johannes F; Van Sikes, Charles; Stitzel, Joel D; Lang, Jason E

    2016-10-26

    Femoral head core decompression is an efficacious joint-preserving procedure for treatment of early stage avascular necrosis. However, postoperative fractures have been described which may be related to the decompression technique used. Femoral head decompressions were performed on 12 matched human cadaveric femora comparing large 8mm single bore versus multiple 3mm small drilling techniques. Ultimate failure strength of the femora was tested using a servo-hydraulic material testing system. Ultimate load to failure was compared between the different decompression techniques using two paired ANCOVA linear regression models. Prior to biomechanical testing and after the intervention, volumetric bone mineral density was determined using quantitative computed tomography to account for variation between cadaveric samples and to assess the amount of bone disruption by the core decompression. Core decompression, using the small diameter bore and multiple drilling technique, withstood significantly greater load prior to failure compared with the single large bore technique after adjustment for bone mineral density (p< 0.05). The 8mm single bore technique removed a significantly larger volume of bone compared to the 3mm multiple drilling technique (p< 0.001). However, total fracture energy was similar between the two core decompression techniques. When considering core decompression for the treatment of early stage avascular necrosis, the multiple small bore technique removed less bone volume, thereby potentially leading to higher load to failure.

  13. Impact of Needle Diameter on Long-Term Dry Needling Treatment of Chronic Lumbar Myofascial Pain Syndrome

    PubMed Central

    Wang, Gang; Gao, Qian; Li, Jun; Tian, Yuling; Hou, Jingshan

    2016-01-01

    ABSTRACT Objective To investigate the impact of diameter of needles on the effect of dry needling treatment of chronic lumbar myofascial pain syndrome. Design Forty-eight patients with chronic lumbar myofascial pain syndrome were randomly allocated to 3 groups. They received dry needling with needles of diameter 0.25 (group A), 0.5 (group B), and 0.9 mm (group C). Visual analog scale evaluation and health survey were conducted at baseline and 3 months after the treatment. Results Visual analog scale scores were significantly different in all groups from baseline to 3 months. Visual analog scale scores at 3 months showed differences between group C and the other 2 groups. When baseline and 3 months after treatment (0 day and 3 months) in each of the 3 groups was compared, there was a difference between group C and group B. The Short Form (36) Health Survey scores from baseline to 3 months were different within the treatment groups. Conclusions Visual analog scale score evaluations at 3 months showed efficacy in all groups. Results of 3 months showed that efficacy of treatment with larger needles (0.9-mm diameter) was better than that of smaller ones (0.5-mm diameter). The Short Form (36) Health Survey scores at 3 months indicated that treatments with needles of varying diameters were all effective, and when the results of 3 months were compared, there was no difference between the 3 groups. PMID:27333534

  14. Imaging for approach selection of TAVI: assessment of the aorto-iliac tract diameter by computed tomography-angiography versus projection angiography.

    PubMed

    Wiegerinck, E M A; Marquering, H A; Oldenburger, N Y; Elattar, M A; Planken, R N; De Mol, B A J M; Piek, J J; Baan, J

    2014-02-01

    The choice of preferred access route for transcatheter aortic valve implantation (TAVI) is mainly guided by the minimal aorto-femoral tract diameter. Currently, projection angiography (XA) and CT-angiography (CTA) are used interchangeably to assess this diameter in the TAVI work-up. We aimed to assess the agreement of XA and CTA diameter measurements in TAVI candidates. Diameters of 700 aorta-iliac segments of 102 TAVI candidates were analyzed on both XA and CTA. The diameters on XA were measured manually, for the CTA-based analysis semi-automated segmentation software was used. Paired sample T test was used to evaluate differences in diameter measurements between the modalities. Disagreement on the suitability for a transfemoral (TF)-TAVI approach was identified. The interobserver agreement for both measurements was assessed by calculating the intraclass correlation coefficient (ICC). The average diameters were 10.1 ± 1.8 mm and 8.4 ± 1.7 for XA and CTA respectively. The mean paired difference was 1.73 mm (p < 0.001). For 18 patients (17.6 %) diameters measured on CTA images, were bilaterally less than 6 mm, whilst XA indicated a minimum diameter exceeding 6 mm. For both modalities, the interobserver agreement was excellent (ICC 0.95). Diameters measured semi-automatically on CTA were statistically significantly smaller compared to XA. This should be acknowledged in the work-up for selecting the most appropriate approach for TAVI. In our population 17.6 % of patients would have been denied a transfemoral TAVI based on CTA measurements, whilst XA suggested diameters sufficient for a TF approach.

  15. 77 FR 46385 - Certain Small Diameter Seamless Carbon and Alloy Standard, Line, and Pressure Pipe From Germany...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ... circular cross-section, not more than 114.3 mm (4.5 inches) in outside diameter, regardless of wall... applications. Pipes produced in non- standard wall thicknesses are commonly referred to as tubes. The seamless..., Characteristics and Uses: Seamless pressure pipes are intended for the conveyance of water, steam,...

  16. 77 FR 56809 - Certain Small Diameter Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ..., not more than 114.3 mm (4.5 inches) in outside diameter, regardless of wall thickness, manufacturing... produced in non- standard wall thicknesses are commonly referred to as tubes. The seamless pipes subject to... Uses: Seamless pressure pipes are intended for the conveyance of water, steam,...

  17. Investigation of the effect of wall materials and tube diameter by heat transfer from horizontal tubes to boiling liquids

    NASA Astrophysics Data System (ADS)

    Siebert, Matthias

    1987-09-01

    Heating surface materials like copper, brass, and stainless steel are studied for their heat transfer coefficient through tubes of 8 mm diameter. Refrigerants considered are R12, R113, R114, methane, and pentane. Heat transfer measurements are carried out in dependence on boiling pressure, liquid properties, bubble formation, and size and bubble deposit thickness on heat surfaces. Nucleate boiling is visualized and observed.

  18. AC conductivity and relaxation mechanism in (Nd1/2Li1/2)(Fe1/2V1/2)O3 ceramics

    NASA Astrophysics Data System (ADS)

    Nath, Susmita; Barik, Subrat Kumar; Choudhary, R. N. P.

    2016-05-01

    In the present study we have synthesized polycrystalline sample of (Nd1/2Li1/2)(Fe1/2V1/2)O3 ceramic by a standard high-temperature solid-state reaction technique. Studies of dielectric and electrical properties of the compound have been carried out in a wide range of temperature (RT - 400 °C) and frequency (1kHz - 1MHz) using complex impedance spectroscopic technique. The imaginary vs. real component of the complex impedance plot (Nyquist plot) of the prepared sample exhibits the existence of grain, grain boundary contributions in the complex electrical parameters and negative temperature coefficient of resistance (NTCR) type behavior like semiconductor. Details study of ac conductivity plot reveals that the material obeys universal Jonscher's power law.

  19. Cloaking spin-(1/2) matter waves

    SciTech Connect

    Lin, De-Hone

    2010-06-15

    A physical construct for the cloaking of relativistic spin-(1/2) matter waves is proposed. It is shown that when the effective energy and mass of relativistic spin-(1/2) particles moving in an effective vector field in a spherical shell are controlled, their matter waves can be perfectly guided through the shell without any distortion or loss; that is, the construct provides a three-dimensional cloaking shell for relativistic spin-(1/2) matter waves. The proposal serves as the basis for some interesting applications such as providing a method to guide the matter waves of spin particles and an ideal setup to exhibit spin-spin interactions as well as perfect quantum interferences of some global effects in spin-(1/2) matter waves.

  20. Cisplatin inhibits MEK1/2

    PubMed Central

    Yamamoto, Tetsu; Tsigelny, Igor F.; Götz, Andreas W.; Howell, Stephen B.

    2015-01-01

    Cisplatin (cDDP) is known to bind to the CXXC motif of proteins containing a ferrodoxin-like fold but little is known about its ability to interact with other Cu-binding proteins. MEK1/2 has recently been identified as a Cu-dependent enzyme that does not contain a CXXC motif. We found that cDDP bound to and inhibited the activity of recombinant MEK1 with an IC50 of 0.28 μM and MEK1/2 in whole cells with an IC50 of 37.4 μM. The inhibition of MEK1/2 was relieved by both Cu+1 and Cu+2 in a concentration-dependent manner. cDDP did not inhibit the upstream pathways responsible for activating MEK1/2, and did not cause an acute depletion of cellular Cu that could account for the reduction in MEK1/2 activity. cDDP was found to bind MEK1/2 in whole cells and the extent of binding was augmented by supplementary Cu and reduced by Cu chelation. Molecular modeling predicts 3 Cu and cDDP binding sites and quantum chemistry calculations indicate that cDDP would be expected to displace Cu from each of these sites. We conclude that, at clinically relevant concentrations, cDDP binds to and inhibits MEK1/2 and that both the binding and inhibitory activity are related to its interaction with Cu bound to MEK1/2. This may provide the basis for useful interactions of cDDP with other drugs that inhibit MAPK pathway signaling. PMID:26155939

  1. Evaluation of the Diode laser (810nm,980nm) on dentin tubule diameter following internal bleaching

    PubMed Central

    Kiomarsi, Nazanin; Salim, Soheil; Sarraf, Pegah; Javad-Kharazifard, Mohammad

    2016-01-01

    Background The aim of this study was to evaluate the effect of diode laser irradiation and bleaching materials on the dentinal tubule diameter after laser bleaching. Material and Methods The dentin discs of 40 extracted third molar were used in this experiment. Each disc surface was divided into two halves by grooving. Half of samples were laser bleached at different wavelengths with two different concentrations of hydrogen peroxide. Other half of each disc with no laser bleaching remained as a negative control. Dentin discs were assigned randomly into four groups (n=10) with following hydrogen peroxide and diode laser wavelength specifications; Group 1 (30% - 810 nm), group 2 (30% - 980 nm), group 3 (46% - 810 nm) and group 4 (46% - 980 nm). All specimens were sent for scanning electron microscopic (SEM) analysis in order to measure tubular diameter in laser treated and control halves. Data were analyzed by ANOVA and Tukey test (p<0.05). Results A significant reduction in dentin tubule diameter was observed in groups 1, 2 and 4. There was no significant difference between groups 1 and 2 and between groups 3 and 4 after bleaching. Conclusions The SEM results showed that diode laser was able to reduce dentin tubule diameter and its effect on dentin was dependent on chemical action of bleaching material. Key words:Laser, diode, dentin, tubule, diameter. PMID:27398172

  2. Fiber diameter distributions in the chinchilla's ampullary nerves

    NASA Technical Reports Server (NTRS)

    Hoffman, Larry F.; Honrubia, Vicente

    2002-01-01

    A morphometric study of the chinchilla's ampullary nerves was conducted to produce an unbiased accounting of the diameter distribution of their constituent fibers. Diameter analyses were determined from 1 microm plastic-embedded nerve sections taken at a plane immediately proximal to the sensory epithelium. We found these nerves to be composed of 2094+/-573 fibers, having diameters that ranged from 0.5 to 8 microm. The distributions of diameters were positively skewed, where approximately 75% of the fibers were found to have diameters less than 3.5 microm. An analysis of the spatial distribution of diameters within the nerve section revealed that the lateralmost areas of the nerve contained larger fractions of fibers within the smallest diameter quintiles, and the central area harbored greater proportions of the larger diameter quintiles. However, significant fractions of all quintiles were found in all areas. These data were integrated with available data of Fernandez et al. (1998) to produce diameter estimates of calyx, dimorphic, and bouton morphology subpopulations. In view of a general relationship between diameter, innervation locus, and an afferent's physiologic characteristics, these data provide the basis for developing a perspective for the in situ distribution of afferent response dynamics.

  3. A λ 3 mm and 1 mm line survey toward the yellow hypergiant IRC +10420⋆

    PubMed Central

    Quintana-Lacaci, G.; Agúndez, M.; Cernicharo, J.; Bujarrabal, V.; Sánchez Contreras, C.; Castro-Carrizo, A.; Alcolea, J.

    2016-01-01

    Aims Our knowledge of the chemical properties of the circumstellar ejecta of the most massive evolved stars is particularly poor. We aim to study the chemical characteristics of the prototypical yellow hypergiant star, IRC +10420. For this purpose, we obtained full line surveys at 1 and 3 mm atmospheric windows. Methods We have identified 106 molecular emission lines from 22 molecular species. Approximately half of the molecules detected are N-bearing species, in particular HCN, HNC, CN, NO, NS, PN, and N2H+. We used rotational diagrams to derive the density and rotational temperature of the different molecular species detected. We introduced an iterative method that allows us to take moderate line opacities into account. Results We have found that IRC +10420 presents high abundances of the N-bearing molecules compared with O-rich evolved stars. This result supports the presence of a N-rich chemistry, expected for massive stars. Our analysis also suggests a decrease of the 12C/13C ratio from ≳ 7 to ~ 3.7 in the last 3800 years, which can be directly related to the nitrogen enrichment observed. In addition, we found that SiO emission presents a significant intensity decrease for high-J lines when compared with older observations. Radiative transfer modeling shows that this variation can be explained by a decrease in the infrared (IR) flux of the dust. The origin of this decrease might be an expansion of the dust shell or a lower stellar temperature due to the pulsation of the star. PMID:27458319

  4. Aortic Intima-Media Thickness and Aortic Diameter in Small for Gestational Age and Growth Restricted Fetuses

    PubMed Central

    Gomez-Roig, M. Dolores; Mazarico, Edurne; Valladares, Esther; Guirado, Laura; Fernandez-Arias, Mireia; Vela, Antonio

    2015-01-01

    Objective The objective of this study is to measure aortic intima-media thickness (aIMT) and aortic diameter (AD) in appropriate for gestational age (AGA) fetuses, small for gestational age (SGA) fetuses, and intrauterine growth restricted (IUGR) fetuses. Methods Case-control study performed between June 2011 and June 2012. Forty-nine AGA fetuses, 40 SGA fetuses, and 35 IUGR fetuses underwent concomitant measurement of aIMT and AD at a mean gestational age of 34.4 weeks. Results Median aIMT was higher in fetuses with IUGR (0.504 mm [95%CI: 0.477-0.530 mm]), than in SGA fetuses (0.466 mm [95% CI: 0.447–0.485 mm]), and AGA fetuses (0.471 mm [95% CI: 0.454-0.488 mm]) (p = 0.023). Mean AD was significantly lower in fetuses with IUGR (4.451 mm [95% CI: 4.258–4.655 mm]), than in AGA fetuses (4.74 mm [95% CI: 4.63-4.843 mm]) (p = 0.028). Conclusions Growth restricted fetuses have a thicker aortic wall than AGA and SGA fetuses, which possibly represents preclinical atherosclerosis and a predisposition to later cardiovascular disease. PMID:26017141

  5. The production of W-0.35HfC (Mol %) wirebar by arc melting and high energy rate extrusion of small diameter ingots

    NASA Astrophysics Data System (ADS)

    Buckman, R. William; Begg, Lester L.

    1991-01-01

    Tungsten alloy fiber reinforced tungsten is a candidate emitter material for space nuclear thermionic multi-kilowatt power systems. Fuel swelling which results in emitter deformation has been a primary concern for being able to achieve long lived (7 years or greater) thermionic fuel elements (TFE) operating at temperatures at or above 1900 K. The tungsten alloy (W-0.35 mo/%HfC) has extremely attractive mechanical properties above 1900 K and is a candidate reinforcement of tungsten for emitters. Because of its high strength, processing of the W-035HfC alloy to small diameter (0.38mm) wire has been difficult and the yield of useable product has been low. The purpose of this work was to demonstrate that by vacuum arc melting 38mm diameter ingots and high energy rate extrusions, small diameter (18mm) rod could be produced which is more compatible with swaging equipment used in tungsten wire production. Six 38 mm diameter ingots of W-0.35 HfC were produced by consumable electrode vacuum arc melting. The ingots were clad in 46 mm diameter molybdenum heated to 2270K and successfully extruded through a zirconia coated die at a reduction ratio of 7:1. The microstructure of the as-extruded bars is highly worked and should be amenable to processing to small diameter wire.

  6. The production of W-0. 35HfC (Mol %) wirebar by arc melting and high energy rate extrusion of small diameter ingots

    SciTech Connect

    Buckman, R.W. Jr. ); Begg, L.L. )

    1991-01-01

    Tungsten alloy fiber reinforced tungsten is a candidate emitter material for space nuclear thermionic multi-kilowatt power systems. Fuel swelling which results in emitter deformation has been a primary concern for being able to achieve long lived (7 years or greater) thermionic fuel elements (TFE) operating at temperatures at or above 1900 K. The tungsten alloy (W-0.35 mo/%HfC) has extremely attractive mechanical properties above 1900 K and is a candidate reinforcement of tungsten for emitters. Because of its high strength, processing of the W-035HfC alloy to small diameter (0.38mm) wire has been difficult and the yield of useable product has been low. The purpose of this work was to demonstrate that by vacuum arc melting 38mm diameter ingots and high energy rate extrusions, small diameter (18mm) rod could be produced which is more compatible with swaging equipment used in tungsten wire production. Six 38 mm diameter ingots of W-0.35 HfC were produced by consumable electrode vacuum arc melting. The ingots were clad in 46 mm diameter molybdenum heated to 2270K and successfully extruded through a zirconia coated die at a reduction ratio of 7:1. The microstructure of the as-extruded bars is highly worked and should be amenable to processing to small diameter wire.

  7. A multicomponent formal [1+2+1+2]-cycloaddition for the synthesis of dihydropyridines.

    PubMed

    Girling, P Ricardo; Batsanov, Andrei S; Shen, Hong C; Whiting, Andrew

    2012-05-18

    Reaction of methoxyvinylmethylketone with different amines and aldehydes under Lewis-acid catalysed conditions results in a novel, formal, step-wise [1+2+1+2]-cycloaddition to give dihydropyridine products.

  8. Structural properties of free-standing 50 mm diameter GaN waferswith (101_0) orientation grown on LiAlO2

    SciTech Connect

    Jasinski, Jacek; Liliental-Weber, Zuzanna; Maruska, Herbert-Paul; Chai, Bruce H.; Hill, David W.; Chou, Mitch M.C.; Gallagher, John J.; Brown, Stephen

    2005-09-27

    (10{und 1}0) GaN wafers grown on (100) face of {gamma}-LiAlO{sub 2} were studied using transmission electron microscopy. Despite good lattice matching in this heteroepitaxial system, high densities of planar structural defects in the form of stacking faults on the basal plane and networks of boundaries located on prism planes inclined to the layer/substrate interface were present in these GaN layers. In addition, significant numbers of threading dislocations were observed. High-resolution electron microscopy indicates that stacking faults present on the basal plane in these layers are of low-energy intrinsic I1type. This is consistent with diffraction contrast experiments.

  9. Improving predictions of root biomechanical properties, is age a better determinant than diameter?

    NASA Astrophysics Data System (ADS)

    Loades, Kenneth; Hallett, Paul; Lynch, Jonathan; Chimungu, Joseph; Bengough, Anthony

    2014-05-01

    Roots mechanically reinforce many soils. Root tensile strength and stiffness is critical for soil stabilisation with plants potentially providing civil engineers a 'green' alternative for soil stabilisation. Relatively little is known on factors influencing root tensile strength. Through a better understanding of these factors the adoption of 'green engineering' techniques by civil engineers will improve. Existing models are limited in their accuracy due to simplistic assumptions to derive root contributions to the resistance of soil to failure. Current models typically use relationships between strength and diameter, however, there are a number of other factors potentially influencing root biomechanical properties. The effects of root age on biomechanical properties have largely been overlooked. Barley (Hordeum vulgare) was grown under differing soil conditions, waterlogged, moderate mechanical impedance and in unimpeded, control, conditions. The root system was excavated and tensile tests performed on root sections along the length of each root axis. Root tensile strength increased with increasing distance along the root axes in control soil from 0.5 MPa to 7.0 MPa at a distance of 800mm from the root tip and from 1.0 Mpa to 8.0 MPa, 500mm from the root tip when under moderate mechanical impedance. Increases in strength were also observed when plants were subjected to waterlogging with tensile strength increasing from 1.0 MPa to 3.0 MPa, 200mm from the root tip. Young's modulus increased from ~10 MPa at the root tip to ~60 MPa 400mm and 800mm from the root tip in mechanically impeded and control treatments respectively. Distance from root tip explained over 47% of the variance in root tensile strength and 34% of root stiffness. Including root diameter in the model led to further improvements in predicting root properties, explaining ~54% of root strength variance and ~49% of root stiffness. Root age has been shown to improve predictions of root tensile strength

  10. Saqqar: A 34 km diameter impact structure in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Kenkmann, Thomas; Afifi, Abdulkader M.; Stewart, Simon A.; Poelchau, Michael H.; Cook, Douglas J.; Neville, Allen S.

    2015-11-01

    Here we present the first proof of an impact origin for the Saqqar circular structure in northwestern Saudi Arabia (Neville et al. ), with an apparent diameter of 34 km, centered at 29°35'N, 38°42'E. The structure is formed in Cambrian-Devonian siliciclastics and is unconformably overlain by undeformed Cretaceous and Paleogene sediments. The age of impact is not well constrained and lies somewhere between 410 and 70 Ma. The subsurface structure is constrained by 2-D reflection seismic profiles and six drilled wells. First-order structural features are a central uplift that rises approximately 2 km above regional datums, surrounded by a ring syncline. The crater rim is defined by circumferential normal faults. The central uplift and ring syncline correspond to a Bouguer gravity high and an annular ring-like low, respectively. The wells were drilled within the central uplift, the deepest among them exceed 2 km depth. Sandstone core samples from these wells show abundant indicators of a shock metamorphic overprint. Planar deformation features (PDFs) were measured with orientations along (0001), {101¯3}, and less frequently along {101¯1} and {101¯4}. Planar fractures (PFs) predominantly occur along (0001) and {101¯1}, and are locally associated with feather features (FFs). In addition, some shocked feldspar grains and strongly deformed mica flakes were found. The recorded shock pressure ranges between 5 and 15 GPa. The preserved level of shock and the absence of an allochthonous crater fill suggest that Saqqar was eroded by 1-2 km between the Devonian and Maastrichtian. The documentation of unequivocal shock features proves the formation of the Saqqar structure by a hypervelocity impact event.

  11. Acceleration of Ab Initio QM/MM Calculations under Periodic Boundary Conditions by Multiscale and Multiple Time Step Approaches.

    PubMed

    Nam, Kwangho

    2014-10-14

    Development of multiscale ab initio quantum mechanical and molecular mechanical (AI-QM/MM) method for periodic boundary molecular dynamics (MD) simulations and their acceleration by multiple time step approach are described. The developed method achieves accuracy and efficiency by integrating the AI-QM/MM level of theory and the previously developed semiempirical (SE) QM/MM-Ewald sum method [J. Chem. Theory Comput. 2005, 1, 2] extended to the smooth particle-mesh Ewald (PME) summation method. In the developed methods, the total energy of the simulated system is evaluated at the SE-QM/MM-PME level of theory to include long-range QM/MM electrostatic interactions, which is then corrected on the fly using the AI-QM/MM level of theory within the real space cutoff. The resulting energy expression enables decomposition of total forces applied to each atom into forces determined at the low-level SE-QM/MM method and correction forces at the AI-QM/MM level, to integrate the system using the reversible reference system propagator algorithm. The resulting method achieves a substantial speed-up of the entire calculation by minimizing the number of time-consuming energy and gradient evaluations at the AI-QM/MM level. Test calculations show that the developed multiple time step AI-QM/MM method yields MD trajectories and potential of mean force profiles comparable to single time step QM/MM results. The developed method, together with message passing interface (MPI) parallelization, accelerates the present AI-QM/MM MD simulations about 30-fold relative to the speed of single-core AI-QM/MM simulations for the molecular systems tested in the present work, making the method less than one order slower than the SE-QM/MM methods under periodic boundary conditions.

  12. Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density?

    PubMed Central

    Zderic, I.; Grechenig, S.; Richards, R. G.; Schmitz, P.; Gueorguiev, B.

    2017-01-01

    Objectives Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. Materials and Methods A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm3 (standard deviation (sd) 52). The anterior pelvic ring fracture was fixed with either one 7.3 mm cannulated screw (Group 1) or two 3.5 mm pelvic cortex screws (Group 2). Progressively increasing cyclic axial loading was applied through the acetabulum. Relative movements in terms of interfragmentary displacement and gap angle at the fracture site were evaluated by means of optical movement tracking. The Wilcoxon signed-rank test was applied to identify significant differences between the groups Results Initial axial construct stiffness was not significantly different between the groups (p = 0.463). Interfragmentary displacement and gap angle at the fracture site were also not statistically significantly different between the groups throughout the evaluated cycles (p ⩾ 0.249). Similarly, cycles to failure were not statistically different between Group 1 (8438, sd 6968) and Group 2 (10 213, sd 10 334), p = 0.379. Failure mode in both groups was characterised by screw cutting through the cancellous bone. Conclusion From a biomechanical point of view, pubic ramus stabilisation with either one large or two small fragment screw osteosynthesis is comparable in osteoporotic bone. However, the two-screw fixation technique is less demanding as the smaller screws deflect at the cortical margins. Cite this article: Y. P. Acklin, I. Zderic, S. Grechenig, R. G. Richards, P

  13. Arterial diameter measurement using high resolution ultrasonography: in vitro validation.

    PubMed

    Brum, Javier; Bia, Daniel; Benech, Nicolas; Balay, Guillermo; Armentano, Ricardo L; Negreira, Carlos

    2011-01-01

    Simultaneous measurement of pressure and diameter in blood vessels or vascular prosthesis is of great importance in cardiovascular research. Knowledge of diameter changes as response to intravascular pressure is the basis to estimate the biomechanical properties of blood vessel. In this work a new method to quantify arterial diameter based in high resolution ultrasonography is proposed. Measurements on an arterial phantom placed on a cardiovascular simulator were performed. The results were compared to sonomicrometry measurements considered as gold standard technique. The obtained results indicate that the new method ensure an optimal diameter quantification. This method presents two main advantages respect to sonomicrometry: is noninvasive and the vessel wall strain can be measured directly.

  14. Diameter Controlled of Carbon Nanotubes Synthesized on Nanoporous Silicon Support

    NASA Astrophysics Data System (ADS)

    Asli, N. A.; Shamsudin, M. S.; Maryam, M.; Yusop, S. F. M.; Suriani, A. B.; Rusop, M.; Abdullah, S.

    2013-06-01

    Carbon nanotubes (CNTs) have been successfully synthesized on nanoporous silicon template (NPSiT) using botanical source, camphor oil. Diameter of CNTs synthesized was controlled by pore size of NPSiT prepared by photo-electrochemical anodization method. The diameter of CNTs grown on different NPSiT corresponded to the pore diameter of NPSiT. FESEM images showed self-organized bundles of fiber-like structures of CNTs with diameter of around 20nm which were successfully grown directly on nanoporous silicon while raman spectra obtained ratio of ID/IG at 0.67.

  15. Research on fiber diameter automatic measurement based on image detection

    NASA Astrophysics Data System (ADS)

    Chen, Xiaogang; Jiang, Yu; Shen, Wen; Han, Guangjie

    2010-10-01

    In this paper, we present a method of Fiber Diameter Automatic Measurement(FDAM). This design is based on image detection technology in order to provide a rapid and accurate measurement of average fiber diameter. Firstly, a preprocessing mechanism is proposed to the sample fiber image by using improved median filtering algorithm, then we introduce edge detection with Sobel operator to detect target fiber, finally diameter of random point and average diameter of the fiber can be measured precisely with searching shortest path algorithm. Experiments are conducted to prove the accuracy of the measurement, and simulations show that measurement errors caused by human factors could be eliminated to a desirable level.

  16. Ultrasonographic Measurement of Subglottic Diameter for Paediatric Cuffed Endotracheal Tube Size Selection: Feasibility Report

    PubMed Central

    Altun, Demet; Sungur, Mukadder Orhan; Ali, Achmet; Bingül, Emre Sertaç; Seyhan, Tülay Özkan; Çamcı, Emre

    2016-01-01

    Objective The aim of this feasibility study was to investigate the first attempt success of ultrasonography (USG) in paediatric patients in predicting an appropriate cuffed endotracheal tube (ETT) size. Methods Fifty children who were 1–10 years of age and who received general anaesthesia with endotracheal intubation for adenoidectomy or adenotonsillectomy were enrolled in the study. In all participants, the transverse diameter of the subglottic airway was measured with USG at the cricoid level without ventilation. The outer diameter (OD) of the maximum allowable ETT was chosen according to the measured subglottic airway diameter. In the presence of resistance to passage of the tube into the trachea or in the absence of an audible leak at airway pressure of >25 cm H2O, the ETT was replaced with a tube whose internal diameter (ID) was 0.5 mm smaller. If a leak was audible at airway pressures of <10 cm H2O, if a seal could not be achieved with a cuff pressure of >25 cm H2O or if a peak airway pressure of >25 cm H2O was observed during ventilation, the tube was changed to a tube one size larger. The OD of the best-fit ETT was converted to the ID. The best-fit ID, the requirement for ETT replacement, the duration of airway diameter measurement by USG and the peak airway pressure were recorded. Results The success rate of the first attempt with USG was 86%; the ETT was replaced in five patients with a tube one size larger and in two patients with a tube one size smaller. Conclusion Our findings show the subglottic diameter measured by USG to be a reliable predictor in estimating the appropriate paediatric ETT size. PMID:28058141

  17. Hyaluronic acid enhancement of expanded polytetrafluoroethylene for small diameter vascular grafts

    NASA Astrophysics Data System (ADS)

    Lewis, Nicole R.

    Cardiovascular disease is the leading cause of mortality and morbidity in the United States and other developed countries. In the United States alone, 8 million people are diagnosed with peripheral arterial disease per year and over 250,000 patients have coronary bypass surgery each year. Autologous blood vessels are the standard graft used in small diameter (<6mm) arterial bypass procedures. Synthetic small diameter grafts have had limited success. While polyethylene (Dacron) and expanded polytetrafluoroethylene (ePTFE) are the most commonly used small diameter synthetic vascular graft materials, there are significant limitations that make these materials unfavorable for use in the low blood flow conditions of the small diameter arteries. Specifically, Dacron and ePTFE grafts display failure due to early thrombosis or late intimal hyperplasia. With the shortage of tissue donors and the limited supply of autologous blood vessels available, there is a need for a small diameter synthetic vascular graft alternative. The aim of this research is to create and characterize ePTFE grafts prepared with hyaluronic acid (HA), evaluate thrombogenic potential of ePTFE-HA grafts, and evaluate graft mechanical properties and coating durability. The results in this work indicate the successful production of ePTFE-HA materials using a solvent infiltration technique. Surface interactions with blood show increased platelet adhesion on HA-modified surfaces, though evidence may suggest less platelet activation and erythrocyte lysis. Significant changes in mechanical properties of HA-modified ePTFE materials were observed. Further investigation into solvent selection, uniformity of HA, endothelialization, and dynamic flow testing would be beneficial in the evaluation of these materials for use in small diameter vascular graft bypass procedures.

  18. Correlation between linezolid zone diameter and minimum inhibitory concentration values determined by regression analysis.

    PubMed

    Dimitriu, G; Poiata, Antonia; Tuchiluş, Cristina; Buiuc, D

    2006-01-01

    Linezolid is a new synthetic antibiotic belonging to the oxazolidinone class, available for the therapy of gram-positive infections, caused by methicillin-resistant staphylococci, vancomycin-resistant enterococci and penicillin-resistant pneumococci. The aim of the study was to determine the in vitro activity of linezolid against staphylococci strains and also to determine the relationship between the minimum inhibitory concentration (MIC) and inhibition zone diameter by calculating the regression analysis. We tested one hundred S. aureus isolates, obtained from healthy persons (naso-pharyngeal swabs) during 2005 year. The antibiotic susceptibility of strains was determined by disk diffusion standardized method and by agar dilution method using a multipoint inoculator. The relationship between the diameter of the inhibition zone produced by a linezolid disc impregnated with a fixed amount (30 eg) was determined by regression performed with the least squares method, considering the log2 of the minimum inhibitory concentrations (MICs) as the independent variable and the zone diameter as the dependent variable. The MIC values expressed in logarithmic form are plotted against inhibition zone diameter (arithmetic scale) of the same strain. The activity of linezolid against staphylococci was very good, with MIC 90 of 1 mg/l. All strains were fully sensitive. The regression line for linezolid passes through a continuous series of points that all are approximately located on the a straight line. For each of the MIC values the differences result no greater than 23 mm in diameter sizes were registered. Regression equation was y= -0.188x + 8.048. In conclusion, the regression line analysis calculated for linezolid, demonstrates a significant correlation between MIC values and the inhibition zone diameters obtained by a 30 mg disc.

  19. In vitro evaluation of Root ZX and Raypex 6 in teeth with different apical diameters

    PubMed Central

    Aydin, Ugur; Karataslioglu, Emrah; Aksoy, Fatih; Yildirim, Cihan

    2015-01-01

    Background: There is a growing interest about electronic apex locators for working length determination. There are several studies dealing with their performance in different conditions. Aims: The aim of this study is to evaluate the accuracy of Root ZX and Raypex 6 in teeth with different apical diameters. Materials and Methods: Actual working length (AWL) of 80 single rooted teeth were determined as 0.5 mm short of apical foramen. The teeth were divided into 4 groups (n = 20). First group (G 0) included teeth with mature apices. Root canals of the other groups (G 32, G 57 and G 72) were enlarged until apical sizes of 0.32, 0.57 and 0.72 mm were obtained. Samples were embedded in alginate and electronic measurements (EM) were performed. Statistical analysis: was achieved with Fisher exact test. Results: Both devices revealed a high rate of success in G 0 and G 32. Their accuracy decreased significantly in G 57 and G 72 groups (P < 0.05). Intra-group results of Root ZX and Raypex 6 were similar (P > 0.05). Conclusions: Root ZX and Raypex 6 are reliable in teeth with mature apices. At foramen diameters exceeding 0.57 mm, their accuracy is susceptible. PMID:25657531

  20. OLIMPO: a balloon-borne, arcminute-resolution survey of the sky at mm and sub-mm wavelengths

    NASA Astrophysics Data System (ADS)

    Masi, S.; Ade, P.; Boscaleri, A.; de Bernardis, P.; de Petris, M.; de Troia, G.; Fabrini, M.; Iacoangeli, A.; Lamagna, L.; Lange, A.; Lubin, P.; Mauskopf, P.; Melchiorri, A.; Melchiorri, F.; Nati, L.; Nati, F.; Orlando, A.; Piacentini, F.; Pierre, M.; Pisano, G.; Polenta, G.; Rephaeli, Y.; Romeo, G.; Salvaterra, L.; Savini, G.; Valiante, E.; Yvon, D.

    2003-08-01

    We describe OLIMPO, a balloon-borne telescope devoted to cosmological and astrophysical surveys in the mm and sub-mm range. We summarize the relevant science (principally surveys of SZ clusters, of the sub-mm cosmic background and observations of galactic and cirrus dust) and the innovative sub-systems we have developed. The test flight of the telescope is planned for July 2004; the long duration flight is planned for the end of 2005.

  1. Performance of the first short model 150 mm aperture Nb$_3$Sn Quadrupole MQXFS for the High- Luminosity LHC upgrade

    SciTech Connect

    Chlachidze, G.; et al.

    2016-08-30

    The US LHC Accelerator Research Program (LARP) and CERN combined their efforts in developing Nb3Sn magnets for the High-Luminosity LHC upgrade. The ultimate goal of this collaboration is to fabricate large aperture Nb3Sn quadrupoles for the LHC interaction regions (IR). These magnets will replace the present 70 mm aperture NbTi quadrupole triplets for expected increase of the LHC peak luminosity by a factor of 5. Over the past decade LARP successfully fabricated and tested short and long models of 90 mm and 120 mm aperture Nb3Sn quadrupoles. Recently the first short model of 150 mm diameter quadrupole MQXFS was built with coils fabricated both by the LARP and CERN. The magnet performance was tested at Fermilab’s vertical magnet test facility. This paper reports the test results, including the quench training at 1.9 K, ramp rate and temperature dependence studies.

  2. Microwave spectrum of 1,2-propanediol

    NASA Astrophysics Data System (ADS)

    Lovas, F. J.; Plusquellic, D. F.; Pate, Brooks H.; Neill, Justin L.; Muckle, Matthew T.; Remijan, Anthony J.

    2009-09-01

    The microwave spectrum of the sugar alcohol 1,2-propanediol (CH 3CHOHCH 2OH) has been measured over the frequency range 6.5-25.0 GHz with several pulsed-beam Fourier-transform microwave spectrometers. Seven conformers of 1,2-propanediol have been assigned and ab initio electronic structure calculations of the 10 lowest energy forms have been calculated. Stark effect measurements were carried out on several of the lowest energy conformers to provide accurate determinations of the dipole moment components and assist in conformer assignment.

  3. The mesiodistal crown diameters of primary dentition in Indonesian Javanese children.

    PubMed

    Kuswandari, Sri; Nishino, Mizuho

    2004-03-01

    Dentition analysis of primary teeth is necessary for recognising and correcting occlusal problems in every stage of dental development to enable normal adult occlusion. To do this, normative data of mesiodistal tooth crown diameters from the same ethnic population are needed. The aims of this study were to gather normative data of mesiodistal crown diameters of primary dentition in Indonesian Javanese children and to compare this normative data with published data of other ethnic populations. Dental casts of 160 males and 137 females with acceptable occlusion, aged 3.25-6.58 years, were taken in Yogyakarta, Indonesia. Mesiodistal diameter was measured as the distance between the anatomic contact points using calipers with accuracy to within 0.05 mm. Each measurement was taken twice on different occasions. The results indicated that the magnitude of asymmetry between right and left teeth was larger in distal teeth within a tooth field, larger in males than females, and larger in mandibular than maxillary teeth. The stability of mesiodistal tooth crown diameters was less in males than in females, and was most prominent in the mandibular central incisor. Sexual dimorphisms were found in, the lateral incisor and first molar in the maxilla, and the canine, first and second molars in the mandible. Compared with other ethnic populations, Indonesian Javanese falls between Hong Kong Chinese and Australian Aboriginal.

  4. SOME OBSERVATIONS ON THE VERTICAL MIGRATION OFDINOFLAGELLATES (1) (2).

    PubMed

    Eppley, R W; Holm-Harisen, O; Strickland, J D

    1968-12-01

    The technique of measuring chlorophyll concentration in vivo by fluorometric analysis has been adapted to studying the diurnal migration of dino-flagellates in the sea and also in a deep tank (3 m in diameter by 10 m deep). The downward migration of Ceratium furca was followed during a bloom off the California coast. The main band of cells migrated from the upper 2 m to a depth of 5 m about 2 hr after sunset, and was dispersed between 5 and 16 m 4.5 hr after sunset. Cultures of Gonyaulax polyedra and Cachonina niei both migrated to the surface of the deep lank during illumination and migrated downward during darkness at a rate of 1-2 mjhr. The downward migration was observed to begin before the light was turned off, indicating that migration is correlated with a cellular periodicity which is to some extent independent of the light regime. Further evidence for such a periodicity was afforded by observations that C. niei start to migrate up in the water column before start of the light period. Nitrogen-limited cells of G. polyedra showed no diurnal migration, but within 1 day after addition of a nitrogen source they recovered their full migratory ability. Cells of C. niei, however, continued to migrate during 5 days of N-starvation, although they did not concentrate in the upper 1/2 m as did the control cells.

  5. Public Library Subject Headings for 16mm Motion Pictures. Revised.

    ERIC Educational Resources Information Center

    California Library Association, Sacramento.

    Suggested subject headings for 16mm motion pictures are listed. The intent of the list is to provide audiovisual librarians with a tool which will aid them in making subject indexes for their printed catalogs. It is also intended as an authority for professional catalogers who may be called upon to catalog 16mm motion pictures. (Author/KKC)

  6. Is smaller better? Comparison of 3-mm and 5-mm leaf size for stereotactic radiosurgery: A dosimetric study

    SciTech Connect

    Chern, Shyh-shi . E-mail: Richard.Chern@hci.utah.edu; Leavitt, Dennis D.; Jensen, Randy L.; Shrieve, Dennis C.

    2006-11-15

    Purpose: To perform a dosimetric comparison of a minimal 3-mm leaf width multileaf collimator (MLC) and a minimal 5-mm MLC in dynamic conformal arc stereotactic radiosurgery for treatment of intracranial lesions. Methods and Materials: The treatment plans of 23 patients previously treated for intracranial lesions in our institution were redone using the BrainSCAN, version 5.3, stereotactic radiosurgery treatment planning system (BrainLAB). For each case, two dynamic conformal arc plans were generated: one using a minimal 3-mm micro-MLC (BrainLAB, Novalis) and one using a minimal 5-mm MLC (Varian Millennium). All arc parameters were the same in each of the two plans, except for the collimator angle settings. The collimator angle settings were optimized for each arc in each plan. A peritumoral rind structure (1 cm) was created to evaluate normal tissue sparing immediately adjacent to the target volume. Conformity indexes (CIs) were calculated for each plan. The dependence of normal tissue sparing and target conformity on target volume (TV) was determined. Results: The TV was 0.14-36.32 cm{sup 3} (median, 5.90). The CI was 1.22-2.60 (median, 1.51) for the 3-mm micro-MLC and 1.23-2.69 (median, 1.60) for the 5-mm MLC. Despite this small difference, it was a statistically significant increase (p < 0.0001) for the 5-mm MLC compared with the 3-mm micro-MLC. Improved normal tissue sparing was demonstrated using the 3-mm micro-MLC compared with the 5-mm MLC by examining the peritumoral rind volumes (PRVs) receiving 50% (PRV{sub 5}), 80% (PRV{sub 8}), and 90% (PRV{sub 9}) of the prescription dose. The reduction in the PRV{sub 5}, PRV{sub 8}, and PRV{sub 9} for the 3-mm micro-MLC compared with the 5-mm MLC was 13.5%, 12.9%, and 11.5%, respectively. The CI decreased with a larger TV, as did the difference in the CIs between the 3-mm micro-MLC and 5-mm MLC. A reduction in the PRV increased with larger TVs. Conclusion: The 3-mm micro-MLC provided better target conformity and

  7. Microfiltration: Effect of channel diameter on limiting flux and serum protein removal.

    PubMed

    Hurt, E E; Adams, M C; Barbano, D M

    2015-06-01

    Our objective was to determine the limiting flux and serum protein (SP) removal at 8, 9 and 10% true protein (TP) in the retentate recirculation loop using 0.1-µm ceramic graded permeability (GP) microfiltration (MF) membranes with 3mm channel diameters (CD). An additional objective was to compare the limiting flux and SP removal between 0.1-µm ceramic GP membranes with 3mm CD and previous research using 4-mm CD membranes. The MF system was operated at 50°C, using a diluted milk protein concentrate with 85% protein on a total solids basis (MPC85) as the MF feed. The limiting flux for the MF of diluted MPC85 was determined at 8, 9, and 10% TP concentration in the recirculation loop. The experiment using the 3-mm CD membranes was replicated 3 times for a total of 9 runs. On the morning of each run MPC85 was diluted with reverse osmosis water to a MF feed TP concentration of 5.4%. In all runs the starting flux was 55 kg/m2 per hour, the flux was then increased in steps until the limiting flux was reached. For the 3-mm CD membranes, the limiting flux was 128±0.3, 109±4, and 97±0.5 kg/m2 per hour at recirculation loop TP concentrations of 8.1±0.07, 9.2±0.04, and 10.2±0.03%, respectively. For the 3-mm CD membranes, increasing the flux from the starting to the limiting flux decreased the SP removal factor from 0.72±0.02 to 0.67±0.01; however, no difference in SP removal factor among the target recirculation loop TP concentrations was detected. The limiting flux at each recirculation loop target TP concentration was lower for the 3- compared with the 4-mm CD membranes. The differences in limiting fluxes between the 3- and 4-mm CD membranes were explained in part by the difference in cross-flow velocity (5.5±0.03 and 7.0±0.03 m/s for the 3- and 4-mm CD membranes, respectively). The SP removal factor was also lower for the 3- compared with the 4-mm CD membranes, indicating that more membrane fouling may have occurred in the 3- versus 4-mm CD membranes.

  8. Mean particle diameters. From statistical definition to physical understanding.

    PubMed

    Alderliesten, Maarten

    2005-01-01

    Mean particle diameters may be used to describe and to model physical, chemical, or physiological properties of products or materials containing dispersed phases. There are different notation systems for these mean diameters, which may cause much confusion. This equally applies to their nomenclature. This article introduces the Moment-Ratio definition system and evaluates briefly the ISO definition system. The ISO system appears to have serious drawbacks. Mean particle diameters can be estimated from histograms of size distributions by Summation (M-R system) and by Integration (ISO system) over the histogram intervals. Summation tends to be more accurate than Integration and is less sensitive to low values of the lower limit of size distributions. The Summation method equations are straightforward and generally applicable. The mathematical formulas of the Integration method are difficult to apply in daily practice, and their complexity may easily hide the physical background of a mean particle diameter. A coherent nomenclature system for denoting mean particle diameters is recommended. This nomenclature system does not contain any ambiguities and clearly conveys the physical meanings of mean particle diameters. This article deals also with an empirical method to select the proper type of mean diameter to describe a physical, chemical, or physiological property of a product or material containing dispersed phases. After calculation of the mean diameters from experimental data, the relationships between the product property and these mean diameters are investigated statistically. The selection method has been illustrated by two examples. The dataset of each example consists of a set of particle size distributions and the corresponding physical product properties that are influenced by the particle sizes. Hypotheses are formulated to explain the types of selected mean diameters. Sharing results from all over the world of applications of the developed selection method

  9. 3D Imaging with a Single-Aperture 3-mm Objective Lens: Concept, Fabrication and Test

    NASA Technical Reports Server (NTRS)

    Korniski, Ron; Bae, Sam Y.; Shearn, Mike; Manohara, Harish; Shahinian, Hrayr

    2011-01-01

    There are many advantages to minimally invasive surgery (MIS). An endoscope is the optical system of choice by the surgeon for MIS. The smaller the incision or opening made to perform the surgery, the smaller the optical system needed. For minimally invasive neurological and skull base surgeries the openings are typically 10-mm in diameter (dime sized) or less. The largest outside diameter (OD) endoscope used is 4mm. A significant drawback to endoscopic MIS is that it only provides a monocular view of the surgical site thereby lacking depth information for the surgeon. A stereo view would provide the surgeon instantaneous depth information of the surroundings within the field of view, a significant advantage especially during brain surgery. Providing 3D imaging in an endoscopic objective lens system presents significant challenges because of the tight packaging constraints. This paper presents a promising new technique for endoscopic 3D imaging that uses a single lens system with complementary multi-bandpass filters (CMBFs), and describes the proof-of-concept demonstrations performed to date validating the technique. These demonstrations of the technique have utilized many commercial off-the-shelf (COTS) components including the ones used in the endoscope objective.

  10. Lunar Brightness Variations with Phase at 4.3-MM Wave Length

    NASA Technical Reports Server (NTRS)

    Coates, Robert J.

    1961-01-01

    The lunar radio observations and interpretations of Piddington and Minnett (1949) and Gibson (1958) show that the lunar brightness variation with phase at millimeter wave lengths can be used to determine the physical properties of the lunar surface. They found that the millimeter-wave brightness lagged the optical phase, and their interpretation was that the millimeter radiation originates below a surface layer that is a very good thermal insulator. The thickness of this layer could not be determined from observations at one frequency. Observations at different frequencies give different results because of the wave-length dependence of the radio absorption by the surface material. The attenuation in the material increases with decreasing wave length, and therefore it is possible, in principle, to determine surface layer thickness from radio observations at several wave lengths. For this reason, observations of lunar radiation were started at the Naval Research Laboratory at a wave length of 4.3 mm. This is half the wave length used by Gibson (1958) in his earlier studies. The radio telescope used for these observations has been described in detail in a previous publication (Coates 1958). The antenna is a parabolic reflector 10 feet in diameter, and it has a beam width of 6.7 minutes of arc at the wave length of 4.3 mm. This is about one-fifth the diameter of the moon. The receiver was a Dicke-type radiometer.

  11. Dataset for the validation and use of DiameterJ an open source nanofiber diameter measurement tool

    PubMed Central

    Hotaling, Nathan A.; Bharti, Kapil; Kriel, Haydn; Simon, Carl G.

    2015-01-01

    DiameterJ is an open source image analysis plugin for ImageJ. DiameterJ produces ten files for every image that it analyzes. These files include the images that were analyzed, the data to create histograms of fiber radius, pore size, fiber orientation, and summary statistics, as well as images to check the output of DiameterJ. DiameterJ was validated with 130 in silico-derived, digital, synthetic images and 24 scanning electron microscope (SEM) images of steel wire samples with a known diameter distribution. Once validated, DiameterJ was used to analyze SEM images of electrospun polymeric nanofibers, including a comparison of different segmentation algorithms. In this article, all digital synthetic images, SEM images, and their segmentations are included. Additionally, DiameterJ’s raw output files, and processed data is included for the reader. The data provided herein was used to generate the figures in DiameterJ: A Validated Open Source Nanofiber Diameter Measurement Tool[1], where more discussion can be found. PMID:26380840

  12. MALT-45: A 7 mm survey of the southern Galaxy

    NASA Astrophysics Data System (ADS)

    Jordan, Christopher Harry

    2015-09-01

    -0 for CS lies within the 7mm waveband, which also contains the poorly understood class I CH3OH maser. Unlike the class II variant, class I masers are not exclusively associated with HMSF, but do appear in star-forming regions across a wide range of evolutionary stages. A large problem for class I CH3OH maser studies is the bias in the targeted searches which have been used to find them; they have only been identified towards other masing regions (such as class II CH3OH), and therefore the properties of these masers are somewhat unclear. In this thesis, results focus on the MALT-45 survey using the Australia Telescope Compact Array (ATCA) in auto-correlation ('single-dish' mode). To date, MALT-45 has mapped the Galactic plane within 330° *lt; < l < 335°, jbj< 0:5°, which contains several known star-forming regions, including the G333 giant molecular cloud. MALT-45 surveys 12 spectral lines, but primarily CS (1-0), class I CH3OH masers and SiO (1-0) v = 0; 1; 2; 3. Bright, extended CS emission is detected across the survey region, and highlight two distinct velocities, due to different spiral arms of the Galaxy. In addition to the previously known 19 class I CH3OH masers, 58 new masers were detected. SiO masers were detected towards 47 regions, in various combinations of vibrational mode v = 1; 2; 3, all towards evolved infrared stars. Thermal SiO v = 0 emission is also detected across the survey region. Major science results from MALT-45 include: (i) A CS to NH3 comparison, which highlights cold, dense clumps as well as hot, evolved clumps. The cold and dense clumps appear to have self-absorption of CS emission in their centres and a relative over-abundance of NH3, while evolved clumps appear to have very little NH3 emission, despite being a dense gas tracer; (ii) Almost all (94 per cent) of ATLASGAL 870 um dust emission point sources are associated with at least a 3σ peak of CS emission; (iii) By comparing with peak CS velocities, class I CH3OH masers are good

  13. 50 CFR 1.2 - Authorized representative.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS § 1.2 Authorized representative. Authorized representative means the subordinate... matters. The Director, U.S. Fish and Wildlife Service is frequently the authorized representative of...

  14. 8 CFR 1.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Nationality DEPARTMENT OF HOMELAND SECURITY GENERAL PROVISIONS DEFINITIONS § 1.2 Definitions. As used in this... otherwise noted, means the Department of Homeland Security. Director or district director prior to March 1... or after March 1, 2003, pursuant to delegation from the Secretary of Homeland Security or...

  15. 1,1,1,2-Tetrafluoroethane

    Integrated Risk Information System (IRIS)

    1,1,1,2 - Tetrafluoroethane ; CASRN 811 - 97 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonca

  16. 1,2,4,5-Tetrachlorobenzene

    Integrated Risk Information System (IRIS)

    1,2,4,5 - Tetrachlorobenzene ; CASRN 95 - 94 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonca

  17. 1,1,2,2-Tetrachloroethane

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 09 / 001 F www.epa.gov / iris TOXICOLOGICAL REVIEW OF 1,1,2,2 - TETRACHLOROETHANE ( CAS No . 79 - 34 - 5 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2010 U.S . Environmental Protection Agency Washington , DC ii DISCLAIMER This docu

  18. 1,2,3-triazolium ionic liquids

    SciTech Connect

    Luebke, David; Nulwala, Hunaid; Tang, Chau

    2014-12-09

    The present invention relates to compositions of matter that are ionic liquids, the compositions comprising substituted 1,2,3-triazolium cations combined with any anion. Compositions of the invention should be useful in the separation of gases and, perhaps, as catalysts for many reactions.

  19. Theoretical study of the photo-isomerisation reactions of 1,2-dihydro-1,2-phosphaborine and 1,2-dihydro-1,2-alumazaine

    NASA Astrophysics Data System (ADS)

    Su, Ming-Der

    2015-07-01

    The mechanisms of the photochemical isomerisation reactions are investigated theoretically using the model systems, 1,2-dihydro-1,2-phosphaborine (5) and 1,2-dihydro-1,2-alumazaine (6), using the CAS(6,6)/6-311G(d,p) and MP2-CAS-(6,6)/6-311++G(3df,3pd)//CAS(6,6)/6-311G(d,p) methods. For each model reactant, three reaction pathways, which lead to three kinds of photo-isomers, are examined. The structures of the conical intersections, which play a key role in such photo-rearrangements, are determined. The thermal (or dark) reactions of the reactant species are also examined, using the same level of theory, to provide a qualitative explanation of the reaction pathways. These model investigations demonstrate that the preferred reaction route for these two aromatic heterocyclics is as follows: reactant → Franck-Condon region → conical intersection → photoproduct. The theoretical evidences anticipate that after irradiation of 5, the photoproduct yield of the Dewar BP-isomer, 8, should be larger than that of the Dewar BP-isomer, 7, whereas no Dewar BP-isomer 9 can be observed. Moreover, the present theoretical data predict after irradiation of 6, all three Dewar AlN-isomers (10, 11, and 12) and the starting molecule, 6, are produced.

  20. 1,1,1,2-Tetrachloroethane

    Integrated Risk Information System (IRIS)

    1,1,1,2 - Tetrachloroethane ; CASRN 630 - 20 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonca

  1. 1,2-Dibromo-3-chloropropane (DBCP)

    Integrated Risk Information System (IRIS)

    1,2 - Dibromo - 3 - chloropropane ( DBCP ) ; CASRN 96 - 12 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessm

  2. The Measurements of the Solar Diameter at the Kepler's Times

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino; Fraschetti, Federico

    2002-12-01

    We examine five measurements of the solar disk diameter made with a pinhole instrument by Tycho in 1591 and Kepler in 1600-1602 [1]. Those are the first accurate measurements of the solar disk diameter available in literature, even if Ptolemy and Copernicus already did such measurements [2].

  3. Method accurately measures mean particle diameters of monodisperse polystyrene latexes

    NASA Technical Reports Server (NTRS)

    Kubitschek, H. E.

    1967-01-01

    Photomicrographic method determines mean particle diameters of monodisperse polystyrene latexes. Many diameters are measured simultaneously by measuring row lengths of particles in a triangular array at a glass-oil interface. The method provides size standards for electronic particle counters and prevents distortions, softening, and flattening.

  4. Reliable Diameter Control of Carbon Nanotube Nanobundles Using Withdrawal Velocity.

    PubMed

    Shin, Jung Hwal; Kim, Kanghyun; An, Taechang; Choi, WooSeok; Lim, Geunbae

    2016-12-01

    Carbon nanotube (CNT) nanobundles are widely used in nanoscale imaging, fabrication, and electrochemical and biological sensing. The diameter of CNT nanobundles should be controlled precisely, because it is an important factor in determining electrode performance. Here, we fabricated CNT nanobundles on tungsten tips using dielectrophoresis (DEP) force and controlled their diameters by varying the withdrawal velocity of the tungsten tips. Withdrawal velocity pulling away from the liquid-air interface could be an important, reliable parameter to control the diameter of CNT nanobundles. The withdrawal velocity was controlled automatically and precisely with a one-dimensional motorized stage. The effect of the withdrawal velocity on the diameter of CNT nanobundles was analyzed theoretically and compared with the experimental results. Based on the attachment efficiency, the withdrawal velocity is inversely proportional to the diameter of the CNT nanobundles; this has been demonstrated experimentally. Control of the withdrawal velocity will play an important role in fabricating CNT nanobundles using DEP phenomena.

  5. Superresolution measurement of nanofiber diameter by modes beating

    NASA Astrophysics Data System (ADS)

    Fenton, E. F.; Solano, P.; Hoffman, J. E.; Orozco, L. A.; Rolston, S. L.; Fatemi, F. K.

    2016-05-01

    Nanofibers are becoming an important tool in quantum information technologies for coupling photonics systems to atomic systems. Nondestructive techniques for characterizing these nanofibers prior to integration into an apparatus are desirable. In this work, we probe the light propagating in a fused silica optical nanofiber (750-nm-diameter) by coupling it evanescently to a 6- μm-diameter microfiber that is scanned along the nanofiber length. This technique is capable of observing all possible beat lengths among different propagating modes. The beat lengths are strongly dependent on the nanofiber diameter and refractive index of the fiber. The steep dependence has enabled measurements of the fiber diameter with sub-Angstrom sensitivity. The diameter extracted from the beat length measurements agrees with a measurement made using scanning electron microscopy. Work supported by NSF.

  6. 77 FR 13079 - Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure Pipe (Over 41/2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    ... International Trade Administration Certain Large Diameter Carbon and Alloy Seamless Standard, Line, and Pressure... and alloy seamless standard, line, and pressure pipe (over 4\\1/2\\ inches) from Japan during the period... administrative review of the antidumping duty order on carbon and alloy seamless standard, line, and...

  7. 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).

  8. Japanese Science Films; a Descriptive and Evaluative Catalog of: 16mm Motion Pictures, 8mm Cartridges, and Video Tapes.

    ERIC Educational Resources Information Center

    Newren, Edward F., Ed.

    One hundred and eighty Japanese 16mm motion pictures, 8mm cartridges, and video tapes produced and judged appropriate for a variety of audience levels are listed in alphabetical order by title with descriptive and evaluative information. A subject heading list and a subject index to the film titles are included, as well as a sample of the…

  9. Influence of the implant diameter with different sizes of hexagon: analysis by 3-dimensional finite element method.

    PubMed

    Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; de Moraes, Sandra Lúcia Dantas; Falcón-Antenucci, Rosse Mary; de Carvalho, Paulo Sérgio Perri; Noritomi, Pedro Yoshito

    2013-08-01

    The aim of this study was to evaluate the stress distribution in implants of regular platforms and of wide diameter with different sizes of hexagon by the 3-dimensional finite element method. We used simulated 3-dimensional models with the aid of Solidworks 2006 and Rhinoceros 4.0 software for the design of the implant and abutment and the InVesalius software for the design of the bone. Each model represented a block of bone from the mandibular molar region with an implant 10 mm in length and different diameters. Model A was an implant 3.75 mm/regular hexagon, model B was an implant 5.00 mm/regular hexagon, and model C was an implant 5.00 mm/expanded hexagon. A load of 200 N was applied in the axial, lateral, and oblique directions. At implant, applying the load (axial, lateral, and oblique), the 3 models presented stress concentration at the threads in the cervical and middle regions, and the stress was higher for model A. At the abutment, models A and B showed a similar stress distribution, concentrated at the cervical and middle third; model C showed the highest stresses. On the cortical bone, the stress was concentrated at the cervical region for the 3 models and was higher for model A. In the trabecular bone, the stresses were less intense and concentrated around the implant body, and were more intense for model A. Among the models of wide diameter (models B and C), model B (implant 5.00 mm/regular hexagon) was more favorable with regard to distribution of stresses. Model A (implant 3.75 mm/regular hexagon) showed the largest areas and the most intense stress, and model B (implant 5.00 mm/regular hexagon) showed a more favorable stress distribution. The highest stresses were observed in the application of lateral load.

  10. Estimation of insertion depth angle based on cochlea diameter and linear insertion depth: a prediction tool for the CI422.

    PubMed

    Franke-Trieger, Annett; Mürbe, Dirk

    2015-11-01

    Beside the cochlear size, the linear insertion depth (LID) influences the insertion depth angle of cochlear implant electrode arrays. For the specific implant CI422 the recommended LID is not fixed but can vary continuously between 20 and 25 mm. In the current study, the influence of cochlea size and LID on the final insertion depth angle was investigated to develop a prediction tool for the insertion depth angle by means of cochlea diameter and LID. Preoperative estimation of insertion depth angles might help surgeons avoid exceeding an intended insertion depth, especially with respect to low-frequency residual hearing preservation. Postoperative, high-resolution 3D-radiographs provided by Flat Panel Computed Volume Tomography (FPCT) were used to investigate the insertion depth angle in 37 CI422 recipients. Furthermore, the FPCT images were used to measure linear insertion depth and diameter of the basal turn of the cochlea. A considerable variation of measured insertion depth angles ranging from 306° to 579° was identified. The measured linear insertion depth ranged from -18.6 to 26.2 mm and correlated positively with the insertion depth angle. The cochlea diameter ranged from 8.11 to 10.42 mm and correlated negatively with the insertion depth angle. The results suggest that preoperatively measured cochlea diameter combined with the option of different array positions by means of LID may act as predictors for the final insertion depth angle.

  11. Development of very small-diameter, inductively coupled magnetized plasma device.

    PubMed

    Kuwahara, D; Mishio, A; Nakagawa, T; Shinohara, S

    2013-10-01

    In order to miniaturize a high-density, inductively coupled magnetized plasma or helicon plasma to be applied to, e.g., an industrial application and an electric propulsion field, small helicon device has been developed. The specifications of this device along with the experimental results are described. We have succeeded in generating high-density (~10(19) m(-3)) plasmas using quartz tubes with very small diameters of 10 and 20 mm, with a radio frequency power ~1200 and 700 W, respectively, in the presence of the magnetic field less than 1 kG.

  12. The 19 mm data recorders similarities and differences

    NASA Technical Reports Server (NTRS)

    Atkinson, Steve

    1992-01-01

    Confusion over the use of non-video 19 mm data recorders is becoming more pronounced as we enter the world of high performance computing. This paper addresses the following: the differences between ID-1, ID-2, MIL-STD-2179 and DD-2; what the proper machine is for various applications; how the machine can be integrated into an environment; and any misconceptions there might be about 19 mm tape recorders. DD-2 and 19 mm instrumentation recorders have missions for which each is well designed. While the differences may appear subtle, understanding the difference between the two is the key to picking the right recorder for a particular application.

  13. 120MM Mortar MIL-STD-1660 Tests

    DTIC Science & Technology

    1994-07-01

    AD-A285 065 FINAL REPORT JULY 1994 REPORT NO. 91-18 120MM MORTAR MIL- STD - 1660 TESTS 94-309 󈧷 Prepared for: Dist.iviiior Unlimited I I U.S. Army...Inidude Securt Ciassificz ion) 120MM Mortar MIL- STD - i660 Tests 12- PERSONAL AUTHOR IS) William R. Meyer ~13a. TYPE OF REPORT 13b. TINE COVERED 14...Armnament Re- earch, Development and Engineering Center (ARDEC), SMCAR-AEP, to conduct MIL- STD - 1660 tests on 120M,\\M mortar rounds on wooden p~allets

  14. Ovulation-inducing factor (OIF/NGF) from seminal plasma origin enhances Corpus Luteum function in llamas regardless the preovulatory follicle diameter.

    PubMed

    Silva, M; Ulloa-Leal, C; Norambuena, C; Fernández, A; Adams, G P; Ratto, M H

    2014-08-01

    Ovulation-inducing factor (OIF) is a protein present in llama seminal plasma that has recently been identified as β-Nerve Growth Factor (NGF) and it induces not only a high rate of ovulation but also appears to have luteotrophic properties in this species. A 2-by-2 experimental design was used to determine the effect of treatments (OIF/NGF vs GnRH) and categories of preovulatory follicle diameter (7-10 vs >10mm) on ovulation rate, CL diameter and function in llamas. Llamas (n=32 llamas per group) were randomly assigned to receive an intramuscular dose of: (a) 1mg purified OIF/NGF in the presence of a follicle of 7-10mm in diameter; (b) 50 μg of GnRH in the presence of a follicle of 7-10mm in diameter; (c) 1mg purified OIF/NGF in the presence of a follicle >10mm in diameter; (d) 50 μg of GnRH in the presence of a follicle >10mm in diameter. Llamas were examined by ultrasonography every 12h from treatment to Day 2 (Day 0=treatment) to detect ovulation, and again on Day 8 to determine CL diameter. Ovulation rates did not differ among groups. There was an effect of preovulatory follicle size on Corpus Luteum diameter at Day 8 (P<0.001), however plasma progesterone concentration (n=15/per group) was higher (P<0.05) in the OIF/NGF - than that of the GnRH - treated group by the same day. We conclude that OIF/NGF treatment enhances CL function regardless preovulatory follicle size at the time of treatment.

  15. Large-diameter total hip arthroplasty modular heads require greater assembly forces for initial stability

    PubMed Central

    MacLeod, A. R.; Sullivan, N. P. T.; Whitehouse, M. R.

    2016-01-01

    Objectives Modular junctions are ubiquitous in contemporary hip arthroplasty. The head-trunnion junction is implicated in the failure of large diameter metal-on-metal (MoM) hips which are the currently the topic of one the largest legal actions in the history of orthopaedics (estimated costs are stated to exceed $4 billion). Several factors are known to influence the strength of these press-fit modular connections. However, the influence of different head sizes has not previously been investigated. The aim of the study was to establish whether the choice of head size influences the initial strength of the trunnion-head connection. Materials and Methods Ti-6Al-4V trunnions (n = 60) and two different sizes of cobalt-chromium (Co-Cr) heads (28 mm and 36 mm; 30 of each size) were used in the study. Three different levels of assembly force were considered: 4 kN; 5 kN; and 6 kN (n = 10 each). The strength of the press-fit connection was subsequently evaluated by measuring the pull-off force required to break the connection. The statistical differences in pull-off force were examined using a Kruskal–Wallis test and two-sample Mann–Whitney U test. Finite element and analytical models were developed to understand the reasons for the experimentally observed differences. Results 36 mm diameter heads had significantly lower pull-off forces than 28 mm heads when impacted at 4 kN and 5 kN (p < 0.001; p < 0.001), but not at 6 kN (p = 0.21). Mean pull-off forces at 4 kN and 5 kN impaction forces were approximately 20% larger for 28 mm heads compared with 36 mm heads. Finite element and analytical models demonstrate that the differences in pull-off strength can be explained by differences in structural rigidity and the resulting interface pressures. Conclusion This is the first study to show that 36 mm Co-Cr heads have up to 20% lower pull-off connection strength compared with 28 mm heads for equivalent assembly forces. This effect is likely

  16. Experimental study on the influence of wire diameter on the internal flow behaviour of woven metal screens

    NASA Astrophysics Data System (ADS)

    Peng, Y. B.; Xu, G. Q.; Luo, X.; Li, H. W.; Liu, Y. P.

    2017-01-01

    Sintered woven wire mesh structures are a classic porous medium. In this paper, we examined the internal flow behaviours of sintered metal wire mesh structures with 0.215mm diameter wires with different porosities. Following previous research results, the influence of woven mesh wire diameter on material penetrating quality was studied. The air that was applied by the gas source was used to investigate structure performance. The Reynolds numbers of the inlet changed from 8.2 to 66.1. The pressures and flow rate at the inlet and outlet were obtained to calculate the permeability and inertia coefficient of each specimen, as well as the friction factors. The experiment results showed that permeability increased and the inertia coefficient decreased as wire diameter increased. Moreover, structures with large wire diameters (d s = 0.215mm) showed better penetrating quality at the same porosity levels. Increases in pressure drop kept pace with increases in diameter. The friction factor decreased as the Reynolds number increased, and tended to be constant.

  17. Consecutive Case Series of Healed Single-Molar Sites Immediately Restored with Wide-Diameter Implants: A 1-Year Evaluation

    PubMed Central

    Cherfane, Pierre; Sojod, Bouchra

    2016-01-01

    Introduction. To evaluate outcomes of wide-diameter (6 mm) implants immediately provisionalized with cement-retained single crowns in posterior molar sites. Materials and Methods. Forty-eight consecutive patients received a total of 53 moderately rough-surface, 6 mm diameter implants in healed sites. All implants were immediately provisionalized with a cement-retained provisional crown. Final prosthesis with cement-retained porcelain fused to metal crowns was delivered 3–6 months later. Patients were followed up for 1 year. Outcome measures were implant failures and success rate, complications, marginal bone levels, bone level changes, papilla index, bleeding on probing, and inflammation. Results. One patient was lost to follow-up. At one year, the implant survival and success rate were 98.1%. The mean marginal bone loss after 1 year was −0.17 ± 1.84 mm. Ideal papilla score was recorded at 83.8% of the sites. More than 95.6% of the sites showed no bleeding or inflammation. No procedure-related or device-related adverse events were reported. Conclusion. Wide-diameter (6 mm) implants can safely and successfully replace single posterior molars. Longer follow-up studies are necessary to evaluate the long-term success of these implants. PMID:27195008

  18. Measurement of the ascending aorta diameter in patients with severe bicuspid and tricuspid aortic valve stenosis using dual-source computed tomography coronary angiography.

    PubMed

    Son, Jee Young; Ko, Sung Min; Choi, Jin Woo; Song, Meong Gun; Hwang, Hweung Kon; Lee, Sook Jin; Kang, Joon-Won

    2011-12-01

    We aimed to evaluate the diagnostic performance of dual-source computed tomography coronary angiography (DSCT-CA) in the measurement of the ascending aorta (AA) diameter and compare the AA diameter in patients with severe bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) stenosis. Eighty-eight consecutive patients (50 men, mean age 60.3 ± 13 year) with severe aortic stenosis (AS) underwent DSCT-CA before aortic valve surgery. Seventy-four of the 88 patients underwent cardiovascular magnetic resonance (CMR). The internal diameter of AA was measured from early-systole with DSCT-CA and CMR by 2 radiologists independently at 4 levels (aortic annulus, sinuses of Valsalva, sinotubular junction, and tubular portion at the right pulmonary artery). The patients were divided in to 2 groups (BAV [n = 53]; TAV [n = 35]) according to operative findings. Patients with BAV were significantly younger than those with TAV (P = 0.0035). Inter-observer agreement of AA diameters at 4 levels with DSCT-CA and CMR was excellent (intraclass correlation coefficient = 0.89-0.97). Also, the DSCT-CA and CMR measurements of the AA diameter strongly correlated (r = 0.871-0.976). Mean diameter of the AA by DSCT-CA was significantly larger in patients with BAV (34.4 ± 8.2 mm) as compared to those with TAV (30.6 ± 5.5 mm). The diameters at the sinuses of Valsalva, sinotubular junction, and tubular portion were significantly larger in BAV than in TAV. Twenty-two of 53 (41.5%) patients with BAV and 2 of 35 (5.7%) patients with TAV had AA dilatation > 45 mm. DSCT-CA allows accurate assessment of the AA diameters in patients with severe AS. Patients with severe BAV stenosis had larger AA diameters and higher prevalence of AA dilatation > 45 mm as compared to those with severe TAV stenosis.

  19. Diameter dependent electron transfer kinetics in semiconductor-enzyme complexes.

    PubMed

    Brown, Katherine A; Song, Qing; Mulder, David W; King, Paul W

    2014-10-28

    Excited state electron transfer (ET) is a fundamental step for the catalytic conversion of solar energy into chemical energy. To understand the properties controlling ET between photoexcited nanoparticles and catalysts, the ET kinetics were measured for solution-phase complexes of CdTe quantum dots and Clostridium acetobutylicum [FeFe]-hydrogenase I (CaI) using time-resolved photoluminescence spectroscopy. Over a 2.0-3.5 nm diameter range of CdTe nanoparticles, the observed ET rate (kET) was sensitive to CaI concentration. To account for diameter effects on CaI binding, a Langmuir isotherm and two geometric binding models were created to estimate maximal CaI affinities and coverages at saturating concentrations. Normalizing the ET kinetics to CaI surface coverage for each CdTe diameter led to k(ET) values that were insensitive to diameter, despite a decrease in the free energy for photoexcited ET (ΔGET) with increasing diameter. The turnover frequency (TOF) of CaI in CdTe-CaI complexes was measured at several molar ratios. Normalization for diameter-dependent changes in CaI coverage showed an increase in TOF with diameter. These results suggest that k(ET) and H2 production for CdTe-CaI complexes are not strictly controlled by ΔG(ET) and that other factors must be considered.

  20. Tomographic Evaluation of Prevalence, Position, and Diameter of the Intraosseous Branch of the Posterior Superior Alveolar Artery in Fully Edentulous Individuals.

    PubMed

    de Oliveira, Guilherme José Pimentel Lopes; Abdala, Marciel Antônio; Nary-Filho, Hugo; Sakakura, Celso Eduardo; Garcia, Valdir Gouveia; Leite, Felipe Coletti

    2017-03-21

    The objective of this study was to evaluate the presence, position, and diameter of the intraosseous branch (IObr) of the posterior superior alveolar artery in fully edentulous patients. Two-hundred five computed tomography scans of fully edentulous patients were analyzed. The presence of the IObr was investigated in the coronal plane at the lateral wall of the maxillary sinus. In patients in whom the IObr was detected, the artery diameter was measured, and the distance from the artery to the bone crest of the alveolar ridge, the maxillary sinus floor, and the distance of the maxillary sinus floor to the bone crest of the alveolar ridge were measured as well. A descriptive statistical analysis of these parameters was conducted. The IObr was identified in the maxillary sinus in 105 tomography images (51.2%), and its diameter varied between 0.8 and 3.3 mm (1.29 ± 0.49 mm). The IObr presented with an artery diameter less than 1 mm in 29% of the patients, between 1 and 2 mm diameter in 61% of the patients and with a diameter larger than 2 mm in 10% of patients. Regarding the IObr topography, the distance from the artery to the floor of the maxillary sinus was 9.62 ± 4.59 mm, and the distance from the artery to the top of crestal bone was 15.15 ± 4.47 mm. At least 10% of edentulous patients are at risk of bleeding complications during interventions in the maxillary sinus.

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

    NASA Technical Reports Server (NTRS)

    Schroeder, R. J.

    1973-01-01

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

  2. Building 931, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  3. Building 904, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  4. Building 1204, oblique view to west, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to west, 135 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  5. Building 909, oblique view to southeast, 135 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 909, oblique view to southeast, 135 mm lens. Building 908 at extreme right for context. - Travis Air Force Base, Handling Crew Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  6. Building 1204, oblique view to east, 90 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to east, 90 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  7. Building 904, oblique view to northeast, 210mm lens Travis ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northeast, 210mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  8. Building 932, oblique view to northwest, 90 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 932, oblique view to northwest, 90 mm lens. Building 933-935 at extreme left. - Travis Air Force Base, Nuclear Weapons Assembly Plant 5, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  9. Building 931, oblique view to northwest, 210 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to northwest, 210 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  10. Building 904, oblique view to northwest, 135 mm lens ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northwest, 135 mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  11. QM/MM methods for studying enzymatic reactions of glycosyltransferases.

    PubMed

    Tvaroška, Igor

    2015-01-01

    Hybrid quantum mechanics and molecular mechanics (QM/MM) methods have become a powerful tool to provide an accurate and effective description of complex biological systems. The QM treatment of the electronic structure of an active site region and the rest of the enzyme by molecular mechanics allows enzymatic reaction to being modeled with including the impact of environment. Different reaction pathways of the enzymatic mechanism can be tested--transition states (TS) and intermediates characterized using QM/MM methods, leading to significant advances in understanding enzymatic reactions. This chapter discusses the ideas and the setting up of the structural and computational models for calculations with QM/MM software. The use of QM/MM methodology is also illustrated using the case of the inverting glycosyltransferase GnT-I.

  12. Increased arterial diameters in the posterior cerebral circulation in men with Fabry disease.

    PubMed

    Uçeyler, Nurcan; Homola, György A; Guerrero González, Hans; Kramer, Daniela; Wanner, Christoph; Weidemann, Frank; Solymosi, László; Sommer, Claudia

    2014-01-01

    A high load of white matter lesions and enlarged basilar arteries have been shown in selected patients with Fabry disease, a disorder associated with an increased stroke risk. We studied a large cohort of patients with Fabry disease to differentially investigate white matter lesion load and cerebral artery diameters. We retrospectively analyzed cranial magnetic resonance imaging scans of 87 consecutive Fabry patients, 20 patients with ischemic stroke, and 36 controls. We determined the white matter lesion load applying the Fazekas score on fluid-attenuated inversion recovery sequences and measured the diameters of cerebral arteries on 3D-reconstructions of the time-of-flight-MR-angiography scans. Data of different Fabry patient subgroups (males-females; normal-impaired renal function) were compared with data of patients with stroke and controls. A history of stroke or transient ischemic attacks was present in 4/30 males (13%) and 5/57 (9%) females with Fabry disease, all in the anterior circulation. Only one man with Fabry disease showed confluent cerebral white matter lesions in the Fazekas score assessment (1%). Male Fabry patients had a larger basilar artery (p<0.01) and posterior cerebral artery diameter (p<0.05) compared to male controls. This was independent of disease severity as measured by renal function and did not lead to changes in arterial blood flow properties. A basilar artery diameter of >3.2 mm distinguished between men with Fabry disease and controls (sensitivity: 87%, specificity: 86%, p<0.001), but not from stroke patients. Enlarged arterial diameters of the posterior circulation are present only in men with Fabry disease independent of disease severity.

  13. The 19 mm date recorders: Similarities and differences

    NASA Technical Reports Server (NTRS)

    Atkinson, Steve

    1991-01-01

    Confusion over the use of non-video 19 mm data recorders is becoming more pronounced in the world of high performance computing. The following issues are addressed: (1) the difference between ID-1, ID-2, MIL-STD-2179, and DD-2; (2) the proper machine for the necessary application; and (3) integrating the machine into an existing environment. Also, an attempt is made to clear up any misconceptions there might be about 19 mm tape recorders.

  14. [Degradation of oil derivatives by Acinetobacter calcoaceticus MM5].

    PubMed

    Marín, M M; Ortiz, M L; Laborda, F

    1994-01-01

    This paper describes the isolation of microorganisms from polluted heating oil. The growth of one of them has been studied (Acinetobacter calcoaceticus MM5) in several linear and branched hydrocarbons as well as the effect of its growth on commercial diesel oil. Acinetobacter calcoaceticus MM5 is not capable of using glucose as its only source of carbon, and it needs the presence of nitrogen and phosphorus sources to degrade any petroleum by-product.

  15. Regiospecific synthesis of 3-substituted imidazo[1,2-a]pyridines, imidazo[1,2-a]pyrimidines, and imidazo[1,2-c]pyrimidine.

    PubMed

    Katritzky, Alan R; Xu, Yong-Jiang; Tu, Hongbin

    2003-06-13

    3-Substituted imidazo[1,2-a]pyridines, imidazo[1,2-a]pyrimidines, and imidazo[1,2-c]pyrimidine were obtained regiospecifically in yields of 35-92% in one pot by reaction of 2-aminopyridines or 2-(or 4-)aminopyrimidines, respectively, with 1,2-bis(benzotriazolyl)-1,2-(dialkylamino)ethanes.

  16. Length to diameter ratio and row number effects in short pin fin heat transfer

    NASA Technical Reports Server (NTRS)

    Brigham, B. A.; Vanfossen, G. J.

    1982-01-01

    The relative effects of pin length to diameter ratio and of pin row geometry on the heat transfer from pin fins, was determined. Array averaged heat transfer coefficients on pin and endwall surfaces were measured for two configurations of staggered arrays of short pin fins (length to diameter ratio of 4). One configuration contained eight streamwise rows of pins, while the other contained only four rows. Results showed that both the 8-row and the 4-row configurations for an L sub p/D of 4, exhibit higher heat transfer than in similar tests on shorter pin fns (L sub p/D of 1/2 and 2). It was also found that for this L sub p/D ratio, the array averaged heat transfer was slightly higher with eight rows of staggered pins than with only four rows.

  17. Fabrication of ф 160 mm convex hyperbolic mirror for remote sensing instrument

    NASA Astrophysics Data System (ADS)

    Kuo, Ching-Hsiang; Yu, Zong-Ru; Ho, Cheng-Fang; Hsu, Wei-Yao; Chen, Fong-Zhi

    2012-10-01

    In this study, efficient polishing processes with inspection procedures for a large convex hyperbolic mirror of Cassegrain optical system are presented. The polishing process combines the techniques of conventional lapping and CNC polishing. We apply the conventional spherical lapping process to quickly remove the sub-surface damage (SSD) layer caused by grinding process and to get the accurate radius of best-fit sphere (BFS) of aspheric surface with fine surface texture simultaneously. Thus the removed material for aspherization process can be minimized and the polishing time for SSD removal can also be reduced substantially. The inspection procedure was carried out by using phase shift interferometer with CGH and stitching technique. To acquire the real surface form error of each sub aperture, the wavefront errors of the reference flat and CGH flat due to gravity effect of the vertical setup are calibrated in advance. Subsequently, we stitch 10 calibrated sub-aperture surface form errors to establish the whole irregularity of the mirror in 160 mm diameter for correction polishing. The final result of the In this study, efficient polishing processes with inspection procedures for a large convex hyperbolic mirror of Cassegrain optical system are presented. The polishing process combines the techniques of conventional lapping and CNC polishing. We apply the conventional spherical lapping process to quickly remove the sub-surface damage (SSD) layer caused by grinding process and to get the accurate radius of best-fit sphere (BFS) of aspheric surface with fine surface texture simultaneously. Thus the removed material for aspherization process can be minimized and the polishing time for SSD removal can also be reduced substantially. The inspection procedure was carried out by using phase shift interferometer with CGH and stitching technique. To acquire the real surface form error of each sub aperture, the wavefront errors of the reference flat and CGH flat due to

  18. Laser direct writing using submicron-diameter fibers.

    PubMed

    Tian, Feng; Yang, Guoguang; Bai, Jian; Xu, Jianfeng; Hou, Changlun; Liang, Yiyong; Wang, Kaiwei

    2009-10-26

    In this paper, a novel direct writing technique using submicron-diameter fibers is presented. The submicron-diameter fiber probe serves as a tightly confined point source and it adopts micro touch mode in the process of writing. The energy distribution of direct writing model is analyzed by Three-Dimension Finite-Difference Time-Domain method. Experiments demonstrate that submicron-diameter fiber direct writing has some advantages: simple process, 350-nm-resolution (lower than 442-nm-wavelength), large writing area, and controllable width of lines. In addition, by altering writing direction of lines, complex submicron patterns can be fabricated.

  19. Measurement of fetal biparietal diameter in owl monkeys (Aotus nancymaae).

    PubMed

    Schuler, A Michele; Brady, Alan G; Tustin, George W; Parks, Virginia L; Morris, Chris G; Abee, Christian R

    2010-09-01

    Owl monkeys are New World primates frequently used in biomedical research. Despite the historical difficulty of breeding owl monkeys in captivity, several productive owl monkey breeding colonies exist currently. The animals in the colony we describe here are not timed-pregnant, and determination of gestational age is an important factor in prenatal care. Gestational age of human fetuses is often determined by using transabdominal measurements of fetal biparietal diameter. The purpose of this study was to correlate biparietal diameter measurements with gestational age in owl monkeys. We found that biparietal diameter can be used to accurately predict gestational age in owl monkeys.

  20. QM/MM free energy simulations: recent progress and challenges.

    PubMed

    Lu, Xiya; Fang, Dong; Ito, Shingo; Okamoto, Yuko; Ovchinnikov, Victor; Cui, Qiang

    Due to the higher computational cost relative to pure molecular mechanical (MM) simulations, hybrid quantum mechanical/molecular mechanical (QM/MM) free energy simulations particularly require a careful consideration of balancing computational cost and accuracy. Here we review several recent developments in free energy methods most relevant to QM/MM simulations and discuss several topics motivated by these developments using simple but informative examples that involve processes in water. For chemical reactions, we highlight the value of invoking enhanced sampling technique (e.g., replica-exchange) in umbrella sampling calculations and the value of including collective environmental variables (e.g., hydration level) in metadynamics simulations; we also illustrate the sensitivity of string calculations, especially free energy along the path, to various parameters in the computation. Alchemical free energy simulations with a specific thermodynamic cycle are used to probe the effect of including the first solvation shell into the QM region when computing solvation free energies. For cases where high-level QM/MM potential functions are needed, we analyze two different approaches: the QM/MM-MFEP method of Yang and co-workers and perturbative correction to low-level QM/MM free energy results. For the examples analyzed here, both approaches seem productive although care needs to be exercised when analyzing the perturbative corrections.

  1. Influence of temperature on the optical system with large diameter off-axis parabolic lenses

    NASA Astrophysics Data System (ADS)

    Su, Yaru; Ruan, Hao; Liu, Jie

    2016-10-01

    In this work, an optical system with large diameter off-axis parabolic lenses was adopted to achieve diffraction gratings by laser interference exposure. The diffraction wavefront aberration caused by temperature variations was simulated using ZEMAX. Through theoretical analysis and optical simulation, it is proved that the diffraction wavefront aberration of holographic grating caused by the pinhole's location errors (it is assumed that when the displacement of pinhole exists along one axis, the locations of the pinhole along the other two orthogonal axes are in a state of precise adjustment ) is much larger when the displacement occurs along z axis than along the other two axes, and the diffraction wavefront aberration is the smallest when the displacement occurs along x axis. If the ambient temperature changes by 1 degree, the PV value is 0.0631λ when the location of the pinhole changes by 0.121mm along z axis, 0.0034λor 0.0672λ when the location of the pinhole changes by 0.002mm along x axis or 0.03mm along y axis. To reach the diffraction limit (that means the PV value is 0.25λ), the decentering value of the pinhole along z axis should be less than 0.0341mm. In conclusion, the position error along z axis is an important factor to influence the PV value of diffraction grating, and the effect of temperature on the PV value of diffraction grating can be neglected.

  2. Mapping of superficial extremity veins: normal diameters and trends in a vascular patient-population.

    PubMed

    Spivack, Dan E; Kelly, Patrick; Gaughan, John P; van Bemmelen, Paul S

    2012-02-01

    Ultrasonic measurement of superficial extremity veins is a common procedure. To establish normal values for vein-size in a population of vascular patients and to assess if measurements remain unchanged over time, we analyzed a database with results of 28,130 measurements in 2420 separate saphenous and 3206 cephalic veins. Mean size of the great saphenous vein ranges from 2.3 mm to 4.4 mm but did not follow a tapering pattern as is often assumed. The distal calf segment is smaller than the ankle segment. The mean cephalic vein size in the upper arm (2.4 mm) was smaller than at the antecubital level (2.7 mm). A decrease in vein diameter over time was noted in many locations and this reached statistical significance (p < 0.005 for the thigh segment). The clinical significance of this is a need to repeat ultrasonic vein-mapping if more than a year elapses between ultrasound and surgical vein harvest.

  3. Synthesis and characterization of polycaprolactone urethane hollow fiber membranes as small diameter vascular grafts.

    PubMed

    Mercado-Pagán, Ángel E; Stahl, Alexander M; Ramseier, Michelle L; Behn, Anthony W; Yang, Yunzhi

    2016-07-01

    The design of bioresorbable synthetic small diameter (<6mm) vascular grafts (SDVGs) capable of sustaining long-term patency and endothelialization is a daunting challenge in vascular tissue engineering. Here, we synthesized a family of biocompatible and biodegradable polycaprolactone (PCL) urethane macromers to fabricate hollow fiber membranes (HFMs) as SDVG candidates, and characterized their mechanical properties, degradability, hemocompatibility, and endothelial development. The HFMs had smooth surfaces and porous internal structures. Their tensile stiffness ranged from 0.09 to 0.11N/mm and their maximum tensile force from 0.86 to 1.03N, with minimum failure strains of approximately 130%. Permeability varied from 1 to 14×10(-6)cm/s, burst pressures from 1158 to 1468mmHg, and compliance from 0.52 to 1.48%/100mmHg. The suture retention forces ranged from 0.55 to 0.81N. HFMs had slow degradation profiles, with 15 to 30% degradation after 8weeks. Human endothelial cells proliferated well on the HFMs, creating stable cell layer coverage. Hemocompatibility studies demonstrated low hemolysis (<2%), platelet activation, and protein adsorption. There were no significant differences in the hemocompatibility of HFMs in the absence and presence of endothelial layers. These encouraging results suggest great promise of our newly developed materials and biodegradable elastomeric HFMs as SDVG candidates.

  4. 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC-113)

    Integrated Risk Information System (IRIS)

    1,1,2 - Trichloro - 1,2,2 - trifluoroethane ( CFC - 113 ) ; CASRN 76 - 13 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health

  5. Performance of 0. 75 mm pitch MWPC'S operating at high rate

    SciTech Connect

    Conetti, S.; Kuzminski, J.; Marchionni, A.; Stairs, D.; Arenton, M.; Chen, T.Y.; Cox, B.; Delchamps, S.; Etemadi, B.; Fortney, L.

    1989-01-01

    Three Multiwire Proportional Chambers (MWPC) with high rate capability have been constructed for Fermi National Accelerator Laboratory experiment 705 (Charmonium and Direct Photon production by ..pi../sup +-/, p and /bar p/ at 300 GeV/c). Each chamber, with a sensitive area of 308 cm/sup 2/, consists of three anode planes, wound with 12.5 ..mu..m diameter gold-plated tungsten/rhenium wire, facing 25 ..mu..m graphite-coated kapton cathode planes at a distance of 3 mm. Wire spacing in two of the MWPC (PC-B1 and PC-B2) is 0.75 mm and 1.00 mm in the third one (PC-B3). After a few weeks of running on ''Magic Gas'' with a beam flux of up to /approximately/10/sup 7/ particles/cm/sup 2/sec, severe damage occurred to the graphite coating. All cathode planes were replaced by aluminized kapton, and the chambers worked successfully for the next 3 months until the end of the run, when a 10% efficiency drop was observed after a total accumulated charge of /approximately/1 C/cm of sense wire. After the end of the run the chambers were disassembled and inspected. A white deposit with a characteristic ''wire pattern'' etched away from the Al coating was observed in the region of the beam spot. 10 refs., 8 figs., 1 tab.

  6. Renal Artery Embolization Combined With Radiofrequency Ablation in a Porcine Kidney Model: Effect of Small and Narrowly Calibrated Microparticles as Embolization Material on Coagulation Diameter, Volume, and Shape

    SciTech Connect

    Sommer, C. M. Kortes, N.; Zelzer, S.; Arnegger, F. U.; Stampfl, U.; Bellemann, N.; Gehrig, T.; Nickel, F.; Kenngott, H. G.; Mogler, C.; Longerich, T.; Meinzer, H. P.; Richter, G. M.; Kauczor, H. U.; Radeleff, B. A.

    2011-02-15

    The purpose of this study was to evaluate the effect of renal artery embolization with small and narrowly calibrated microparticles on the coagulation diameter, volume, and shape of radiofrequency ablations (RFAs) in porcine kidneys. Forty-eight RFAs were performed in 24 kidneys of 12 pigs. In 6 animals, bilateral renal artery embolization was performed with small and narrowly calibrated microparticles. Upper and lower kidney poles were ablated with identical system parameters. Applying three-dimensional segmentation software, RFAs were segmented on registered 2 mm-thin macroscopic slices. Length, depth, width, volume{sub s}egmented, and volume{sub c}alculated were determined to describe the size of the RFAs. To evaluate the shape of the RFAs, depth-to-width ratio (perfect symmetry-to-lesion length was indicated by a ratio of 1), sphericity ratio (perfect sphere was indicated by a sphericity ratio of 1), eccentricity (perfect sphere was indicated by an eccentricity of 0), and circularity (perfect circle was indicated by a circularity of 1) were determined. Embolized compared with nonembolized RFAs showed significantly greater depth (23.4 {+-} 3.6 vs. 17.2 {+-} 1.8 mm; p < 0.001) and width (20.1 {+-} 2.9 vs. 12.6 {+-} 3.7 mm; p < 0.001); significantly larger volume{sub s}egmented (8.6 {+-} 3.2 vs. 3.0 {+-} 0.7 ml; p < 0.001) and volume{sub c}alculated (8.4 {+-} 3.0 ml vs. 3.3 {+-} 1.1 ml; p < 0.001); significantly lower depth-to-width (1.17 {+-} 0.10 vs. 1.48 {+-} 0.44; p < 0.05), sphericity (1.55 {+-} 0.44 vs. 1.96 {+-} 0.43; p < 0.01), and eccentricity (0.84 {+-} 0.61 vs. 1.73 {+-} 0.91; p < 0.01) ratios; and significantly greater circularity (0.62 {+-} 0.14 vs. 0.45 {+-} 0.16; p < 0.01). Renal artery embolization with small and narrowly calibrated microparticles affected the coagulation diameter, volume, and shape of RFAs in porcine kidneys. Embolized RFAs were significantly larger and more spherical compared with nonembolized RFAs.

  7. SPECTRAL LINE SURVEY TOWARD THE YOUNG MASSIVE PROTOSTAR NGC 2264 CMM3 IN THE 4 mm, 3 mm, AND 0.8 mm BANDS

    SciTech Connect

    Watanabe, Yoshimasa; Sakai, Nami; López-Sepulcre, Ana; Furuya, Ryuta; Yamamoto, Satoshi; Sakai, Takeshi; Hirota, Tomoya; Liu, Sheng-Yuan; Su, Yu-Nung

    2015-08-20

    Spectral line survey observations are conducted toward the high-mass protostar candidate NGC 2264 CMM3 in the 4, 3, and 0.8 mm bands with the Nobeyama 45 m telescope and the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope. In total, 265 emission lines are detected in the 4 and 3 mm bands, and 74 emission lines in the 0.8 mm band. As a result, 36 molecular species and 30 isotopologues are identified. In addition to the fundamental molecular species, many emission lines of carbon-chain molecules such as HC{sub 5}N, C{sub 4}H, CCS, and C{sub 3}S are detected in the 4 and 3 mm bands. Deuterated molecular species are also detected with relatively strong intensities. On the other hand, emission lines of complex organic molecules such as HCOOCH{sub 3} and CH{sub 3}OCH{sub 3} are found to be weak. For the molecules for which multiple transitions are detected, rotation temperatures are derived to be 7–33 K except for CH{sub 3}OH. Emission lines with high upper-state energies (E{sub u} > 150 K) are detected for CH{sub 3}OH, indicating the existence of a hot core. In comparison with the chemical composition of the Orion KL, carbon-chain molecules and deuterated molecules are found to be abundant in NGC 2264 CMM3, while sulfur-bearing species and complex organic molecules are deficient. These characteristics indicate the chemical youth of NGC 2264 CMM3 in spite of its location at the center of the cluster forming core, NGC 2264 C.

  8. Spectral Line Survey toward the Young Massive Protostar NGC 2264 CMM3 in the 4 mm, 3 mm, and 0.8 mm Bands

    NASA Astrophysics Data System (ADS)

    Watanabe, Yoshimasa; Sakai, Nami; López-Sepulcre, Ana; Furuya, Ryuta; Sakai, Takeshi; Hirota, Tomoya; Liu, Sheng-Yuan; Su, Yu-Nung; Yamamoto, Satoshi

    2015-08-01

    Spectral line survey observations are conducted toward the high-mass protostar candidate NGC 2264 CMM3 in the 4, 3, and 0.8 mm bands with the Nobeyama 45 m telescope and the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope. In total, 265 emission lines are detected in the 4 and 3 mm bands, and 74 emission lines in the 0.8 mm band. As a result, 36 molecular species and 30 isotopologues are identified. In addition to the fundamental molecular species, many emission lines of carbon-chain molecules such as HC5N, C4H, CCS, and C3S are detected in the 4 and 3 mm bands. Deuterated molecular species are also detected with relatively strong intensities. On the other hand, emission lines of complex organic molecules such as HCOOCH3 and CH3OCH3 are found to be weak. For the molecules for which multiple transitions are detected, rotation temperatures are derived to be 7-33 K except for CH3OH. Emission lines with high upper-state energies (Eu > 150 K) are detected for CH3OH, indicating the existence of a hot core. In comparison with the chemical composition of the Orion KL, carbon-chain molecules and deuterated molecules are found to be abundant in NGC 2264 CMM3, while sulfur-bearing species and complex organic molecules are deficient. These characteristics indicate the chemical youth of NGC 2264 CMM3 in spite of its location at the center of the cluster forming core, NGC 2264 C.

  9. Influence of lubricant oil on heat transfer performance of refrigerant flow boiling inside small diameter tubes. Part II: Correlations

    SciTech Connect

    Wei, Wenjian; Ding, Guoliang; Hu, Haitao; Wang, Kaijian

    2007-10-15

    The predictive ability of the available state-of-the-art heat transfer correlations of refrigerant-oil mixture is evaluated with the present experiment data of small tubes with inside diameter of 6.34 mm and 2.50 mm. Most of these correlations can be used to predict the heat transfer coefficient of 6.34 mm tube, but none of them can predict heat transfer coefficient of 2.50 mm tube satisfactorily. A new correlation of two-phase heat transfer multiplier with local properties of refrigerant-oil mixture is developed. This correlation approaches the actual physical mechanism of flow boiling heat transfer of refrigerant-oil mixture and can reflect the actual co-existing conditions of refrigerant and lubricant oil. More than 90% of the experiment data of both test tubes have less than {+-}20% deviation from the prediction values of the new correlations. (author)

  10. Fabrication of 30 mm long baseline single-layer 2nd-order high- Tc SQUID gradiometer

    NASA Astrophysics Data System (ADS)

    Lee, Soon-Gul; Oh, Soo-Ho; Kang, Chan Seok; Kim, In-Seon

    2007-09-01

    We have designed and fabricated a 30 mm long baseline 2nd-order SQUID gradiometer from a single-layer YBa 2Cu 3O 7 film. The design rule was the same as that of our previous study on short baseline gradiometers. Three linearly aligned 10.2 mm × 10.2 mm pickup loops were coupled directly to a dc SQUID to measure ∂ 2Bz/∂ x2. The device had an overall size of 70.2 mm × 10.6 mm and was patterned from a single layer of YBa 2Cu 3O 7 film on a sapphire substrate by argon ion milling with a photoresist mask. The Josephson element of the SQUID was YBa 2Cu 3O 7 nanobridges formed by focused ion beam writing technique. Balancing of the device was achieved by optimizing the inductance of the center loop. Estimated sensitivity of the gradiometer was ∼1.8 × 10 -10 T/m 2/Hz 1/2, which is equivalent to a field noise of 160 fT/Hz 1/2, for an intrinsic SQUID flux noise of 10 -5 ϕ0/Hz 1/2.

  11. Wavelength dependence of the apparent diameter of retinal blood vessels

    NASA Astrophysics Data System (ADS)

    Park, Robert; Twietmeyer, Karen; Chipman, Russell; Beaudry, Neil; Salyer, David

    2005-04-01

    Imaging of retinal blood vessels may assist in the diagnosis and monitoring of diseases such as glaucoma, diabetic retinopathy, and hypertension. However, close examination reveals that the contrast and apparent diameter of vessels are dependent on the wavelength of the illuminating light. In this study multispectral images of large arteries and veins within enucleated swine eyes are obtained with a modified fundus camera by use of intravitreal illumination. The diameters of selected vessels are measured as a function of wavelength by cross-sectional analysis. A fixed scale with spectrally independent dimension is placed above the retina to isolate the chromatic effects of the imaging system and eye. Significant apparent differences between arterial and venous diameters are found, with larger diameters observed at shorter wavelengths. These differences are due primarily to spectral absorption in the cylindrical blood column.

  12. SMALL DIAMETER PRECEMENT LINING FROM CATWALK ABOVE. United States ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SMALL DIAMETER PRE-CEMENT LINING FROM CATWALK ABOVE. - United States Pipe & Foundry Company Plant, Coating, Painting, Lining & Packaging Building, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  13. SMALL DIAMETER CEMENT LINING FROM STAIRWAY. United States Pipe ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SMALL DIAMETER CEMENT LINING FROM STAIRWAY. - United States Pipe & Foundry Company Plant, Coating, Painting, Lining & Packaging Building, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  14. SMALL DIAMETER STENCILING, ROLLING OVER STAMP. United States Pipe ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SMALL DIAMETER STENCILING, ROLLING OVER STAMP. - United States Pipe & Foundry Company Plant, Coating, Painting, Lining & Packaging Building, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  15. LARGE DIAMETER WATER TEST MACHINE, TEST FINISHED, PIPE ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LARGE DIAMETER - WATER TEST MACHINE, TEST FINISHED, PIPE ON CAR. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  16. Synthesis of very small diameter silica nanofibers using sound waves.

    PubMed

    Datskos, Panos; Chen, Jihua; Sharma, Jaswinder

    2014-07-14

    Silica nanofibers of an average diameter ≈30 nm and length ≈100 μm have been synthesized using an unprecedented strategy: sound waves. A new phenomenon, spinning off the nanofibers at silica rod tips, is also observed.

  17. Diameter estimation of cylinders by the rigorous diffraction model.

    PubMed

    Sanchez-Brea, Luis Miguel

    2005-07-01

    The Fraunhofer diffraction formula is commonly used for estimating the diameter of thin cylinders by far field diffractometry. However, an experimental systematic overestimation of the value of the cylinder diameter by this diffraction model and other three-dimensional models has been reported when this estimation is compared with those obtained from interferometric techniques. In this work, a rigorous electromagnetic diffraction model is analyzed to determine the cylinder diameter by using the envelope minima of the far field diffraction pattern. The results of this rigorous model are compared with those from the Fraunhofer diffraction formula. The overestimation by the Fraunhofer model is predicted theoretically, presenting a dependence on the wavelength, the polarization state of the incident wave, and the cylinder diameter. The discrepancies are shown to be due to the three-dimensional geometry.

  18. Northern view of inside diameter welding station of the saw ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Northern view of inside diameter welding station of the saw line in bay9 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  19. Eddy sensors for small diameter stainless steel tubes.

    SciTech Connect

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  20. Development of welded metal bellows having minimum effective diameter change

    NASA Technical Reports Server (NTRS)

    Henschel, J. K.; Stevens, J. B.; Harvey, A. C.; Howland, J. S.; Rhee, S. S.

    1972-01-01

    A program of analysis, design, and fabrication was conducted to develop welded metal bellows having a minimum change in effective diameter for cryogenic turbomachinery face seal applications. Linear analysis of the principle types of bellows provided identification of concepts capable of meeting basic operation requirements. For the 6-inch (.152 m) mean diameter, 1.5-inch free length bellows studied, nonlinear analysis showed that opposed and nested toroidal bellows plates stiffened by means of alternating stiffener rings were capable of maintaining constant effective diameter within 0.3% and 0.1% respectively under the operating conditions of interest. Changes in effective diameter were due principally to bellows axial deflection with pressure differential having a lesser influence. Fabrication problems associated with joining the thin bellows plates to the relatively heavy stiffener rings were encountered and precluded assembly and testing of a bellows core. Fabrication problems are summarized and recommended fabrication methods for future effort are presented.

  1. Acoustic fill factors for a 120 inch diameter fairing

    NASA Technical Reports Server (NTRS)

    Lee, Y. Albert

    1992-01-01

    Data from the acoustic test of a 120-inch diameter payload fairing were collected and an analysis of acoustic fill factors were performed. Correction factors for obtaining a weighted spatial average of the interior sound pressure level (SPL) were derived based on this database and a normalized 200-inch diameter fairing database. The weighted fill factors were determined and compared with statistical energy analysis (VAPEPS code) derived fill factors. The comparison is found to be reasonable.

  2. Thermal resistance of ultra-small-diameter disk microlasers

    SciTech Connect

    Zhukov, A. E. Kryzhanovskaya, N. V.; Maximov, M. V.; Lipovskii, A. A.; Savelyev, A. V.; Shostak, I. I.; Moiseev, E. I.; Kudashova, Yu. V.; Kulagina, M. M.; Troshkov, S. I.

    2015-05-15

    The thermal resistance of AlGaAs/GaAs microlasers of the suspended-disk type with a diameter of 1.7–4 μm and InAs/InGaAs quantum dots in the active region is inversely proportional to the squared diameter of the microdisk. The proportionality factor is 3.2 × 10{sup −3} (K cm{sup 2})/W, and the thermal resistance is 120–20°C/mW.

  3. Spin-1/2 Optical Lattice Clock

    NASA Astrophysics Data System (ADS)

    Lemke, N. D.; Ludlow, A. D.; Barber, Z. W.; Fortier, T. M.; Diddams, S. A.; Jiang, Y.; Jefferts, S. R.; Heavner, T. P.; Parker, T. E.; Oates, C. W.

    2009-08-01

    We experimentally investigate an optical clock based on Yb171 (I=1/2) atoms confined in an optical lattice. We have evaluated all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of 3.4×10-16, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2(0.7) Hz.

  4. Aldebaran's angular diameter: How well do we know it?

    NASA Astrophysics Data System (ADS)

    Richichi, A.; Roccatagliata, V.

    2005-04-01

    The bright, well-known K5 giant Aldebaran, α Tau, is probably the star with the largest number of direct angular diameter determinations, achieved over a long time by several authors using various techniques. In spite of this wealth of data, or perhaps as a direct result of it, there is not a very good agreement on a single angular diameter value. This is particularly unsettling if one considers that Aldebaran is also used as a primary calibrator for some angular resolution methods, notably for optical and infrared long baseline interferometry. Directly connected to Aldebaran's angular diameter and its uncertainties is its effective temperature, which also has been used for several empirical calibrations. Among the proposed explanations for the elusiveness of an accurate determination of the angular diameter of Aldebaran are the possibility of temporal variations as well as a possible dependence of the angular diameter on the wavelength. We present here a few, very accurate new determinations obtained by means of lunar occultations and long baseline interferometry. We derive an average value of 19.96±0.03 milliarcsec for the uniform disk diameter. The corresponding limb-darkened value is 20.58±0.03 milliarcsec, or 44.2±0.9 R⊙. We discuss this result, in connection with previous determinations and with possible problems that may affect such measurements. Based on observations collected at TIRGO (Gornergrat, Switzerland). TIRGO is operated by CNR - CAISMI Arcetri, Italy.

  5. Understanding the effect of carbon status on stem diameter variations

    PubMed Central

    De Swaef, Tom; Driever, Steven M.; Van Meulebroek, Lieven; Vanhaecke, Lynn; Marcelis, Leo F. M.; Steppe, Kathy

    2013-01-01

    Background Carbon assimilation and leaf-to-fruit sugar transport are, along with plant water status, the driving mechanisms for fruit growth. An integrated comprehension of the plant water and carbon relationships is therefore essential to better understand water and dry matter accumulation. Variations in stem diameter result from an integrated response to plant water and carbon status and are as such a valuable source of information. Methods A mechanistic water flow and storage model was used to relate variations in stem diameter to phloem sugar loading and sugar concentration dynamics in tomato. The simulation results were compared with an independent model, simulating phloem sucrose loading at the leaf level based on photosynthesis and sugar metabolism kinetics and enabled a mechanistic interpretation of the ‘one common assimilate pool’ concept for tomato. Key Results Combining stem diameter variation measurements and mechanistic modelling allowed us to distinguish instantaneous dynamics in the plant water relations and gradual variations in plant carbon status. Additionally, the model combined with stem diameter measurements enabled prediction of dynamic variables which are difficult to measure in a continuous and non-destructive way, such as xylem water potential and phloem hydrostatic potential. Finally, dynamics in phloem sugar loading and sugar concentration were distilled from stem diameter variations. Conclusions Stem diameter variations, when used in mechanistic models, have great potential to continuously monitor and interpret plant water and carbon relations under natural growing conditions. PMID:23186836

  6. Streamer velocity and diameter observed in sprites and laboratory discharges

    NASA Astrophysics Data System (ADS)

    Stenbaek-Nielsen, H.; Kammae, T.; McHarg, M. G.; Haaland, R. K.

    2012-12-01

    Analysis of the relation between the reduced diameter (scaled with atmospheric density) and velocity of sprite streamers has found a roughly linear dependence (Kanmae et al., J. Phys. D, 45, 275203, 2012). This linear dependence agrees with modeling by Naidis (Phys. Rev. E, 79,057401, 2009). Comparing observations of diameters in sprites with those of laboratory streamers (Briels et al., J. Phys. D, 39, 5201, 2006) show that the laboratory streamers, while following the linear diameter-velocity relation, have smaller diameters (and velocities) than what we observe in sprite streamers. We suggest that this may be an artifact of the smaller reduced scale sizes of the laboratory experimental setup where the streamers are observed much earlier relative to streamer onset. Another systematic difference between laboratory and sprite streamers is that while sprite streamers often split into many sub-streamers, laboratory streamers only rarely split into more than two. There have been several studies of streamer stability against splitting. Lui & Pasko (J. Geophys. Res. 109, A04301, 2004) found that the streamer radius limit of 97 m at 70 km altitude for stability. Sprite streamers are often significantly larger, suggesting that the relatively larger streamer diameter in sprites compared to laboratory streamers is responsible for the larger number of sub streamers. However, we note that the distance sprite streamers travel between splitting is highly varying between events and seemingly not related to the sprite diameter.

  7. A 5-mm piezo-scanning fiber device for high speed ultrafast laser microsurgery

    PubMed Central

    Ferhanoglu, Onur; Yildirim, Murat; Subramanian, Kaushik; Ben-Yakar, Adela

    2014-01-01

    Towards developing precise microsurgery tools for the clinic, we previously developed image-guided miniaturized devices using low repetition rate amplified ultrafast lasers for surgery. To improve the speed of tissue removal while reducing device diameter, here we present a new 5-mm diameter device that delivers high-repetition rate laser pulses for high speed ultrafast laser microsurgery. The device consists of an air-core photonic bandgap fiber (PBF) for the delivery of high energy pulses, a piezoelectric tube actuator for fiber scanning, and two aspheric lenses for focusing the light. Its inline optical architecture provides easy alignment and substantial size reduction to 5 mm diameter as compared to our previous MEMS-scanning devices while realizing improved intensity squared (two-photon) lateral and axial resolutions of 1.16 μm and 11.46 μm, respectively. Our study also sheds light on the maximum pulse energies that can be delivered through the air-core PBF and identifies cladding damage at the input facet of the fiber as the limiting factor. We have achieved a maximum energy delivery larger than 700 nJ at 92% coupling efficiency. An in depth analysis reveals how this value is greatly affected by possible slight misalignments of the beam during coupling and the measured small beam pointing fluctuations. In the absence of these imperfections, self-phase modulation becomes the limiting factor for the maximum energy delivery, setting the theoretical upper bound to near 2 μJ for a 1-m long, 7-μm, air-core PBF. Finally, the use of a 300 kHz repetition rate fiber laser enabled rapid ablation of 150 µm x 150 µm area within only 50 ms. Such ablation speeds can now allow the surgeons to translate the surgery device as fast as ~4 mm/s to continuously remove a thin layer of a 150 µm wide tissue. Thanks to a high optical transmission efficiency of the in-line optical architecture of the device and improved resolution, we could successfully perform ablation of

  8. Fabrication of microporous polyurethane by spray phase inversion method as small diameter vascular grafts material.

    PubMed

    Khorasani, M T; Shorgashti, S

    2006-05-01

    Microporous polyurethane vascular prostheses with a 4 mm diameter and 0.3-0.4 mm wall thickness were fabricated by a spray phase inversion technique. In this study, the effect of distance between spray guns (SG) and rotating mandrel (RM), the effect of rate of rotating mandrel (RRM), and the type of nonsolvent on pore morphology of PU films were evaluated using scanning electron microscopy (SEM) technique. It was observed that when the distance between SG and RM was increased or the rate of RM was decreased, the porosity of PU films increased and consequently the tensile strength decreased and compliance value increased. Compliance was measured in vitro by volume and vessel diameter changes. Furthermore, when the coagulant (water) was changed to the water/methanol, the porosity of PU film increased and porous morphology changed to filamentous morphology. Attachment of anchorage dependent cells, namely L929 fibroblast cells, were investigated in stationary culture conditions. The cells adhesion and cells growth were studied using optical photomicrographs. The results show that by increasing the porosity content of PU films would consequently increase the cell ingrowths.

  9. Image correlation algorithm for measuring lymphocyte velocity and diameter changes in contracting microlymphatics.

    PubMed

    Dixon, J Brandon; Gashev, Anatoliy A; Zawieja, David C; Moore, James E; Coté, Gerard L

    2007-03-01

    Efforts have recently been made to estimate wall shear stress throughout the contractile cycle of mesenteric rat lymphatics with a high speed video microscopy system. This was prompted by reports in the literature that lymphatic pumping is related to wall shear stress. While one can estimate wall shear stress by tracking lymphocyte velocity, it is prohibitively tedious to manually track particles over a reasonable time frame for a good number of experiments. To overcome this, an image correlation method similar to digital particle imaging velocimetry was developed and tested on contracting lymphatics to measure both vessel diameter and fluid velocity. The program tracked temporal fluctuations in spatially averaged velocity with a standard error of prediction of 0.4 mm/s. From these studies we have measured velocities ranging from -2 to 4 mm/s. Diameter changes were also measured with a standard error of 7 microm. These algorithms and techniques could be beneficial for investigating various changes in contractile behavior as a function of changes in velocity and wall shear stress.

  10. Crystal-melt interface shape of Czochralski-grown large diameter germanium crystals

    NASA Technical Reports Server (NTRS)

    Roth, M.; Azoulay, M.; Gafni, G.; Mizrachi, M.

    1990-01-01

    Crystal-melt interface shapes of 100 to 200 mm diameter 111-line Ge grown by the Czochralski technique have been examined using the method of fast withdrawal from the melt. Initially, the interface shape is convex, then transforms gradually into a sigmoidal shape, becomes nearly planar at about one third of the final crystal length, and finally assumes a concave profile with progressively increasing curvature. The nearly planar interface has a double-facet structure, with an annular facet at the edge of the crystal in addition to the central (111) facet. Formation of the annular facet is accompanied by a giant oscillation of the pull rate when the maximum average pull rate is exceeded. Such oscillation is detrimental to crystal quality, since it introduces a region of high dislocation density. An average pull rate maximum of 2 cm/h has been found to allow for a smooth growth of 200 mm diameter crystals. The origin of the pull rate perturbation is discussed in terms of an instantaneous change in the equilibrium shape of the meniscus.

  11. Spirosymplokos deltaeiberi nov. gen., nov. sp.: variable-diameter composite spirochete from microbial mats

    NASA Technical Reports Server (NTRS)

    Guerrero, R.; Ashen, J.; Sole, M.; Margulis, L.

    1993-01-01

    Large (up to 100 micrometers long), loosely coiled, free-living spirochetes with variable diameters (from 0.4 to 3 micrometers in the same cell) were seen at least 40 times between August 1990 and January 1993. These spirochetes were observed in mud water and enrichment media from highly specific habitats in intertidal evaporite flats at three disjunct localities, one in Spain and two in Mexico. All three are sites of commercial saltworks. Associated with Microcoleus chthonoplastes the large spirochetes from Spain display phototaxis and a composite organization. Shorter and smaller-diameter spirochetes are seen inside both healthy and spent periplasm of larger ones. Small spirochetes attached to large ones have been observed live. From two to twelve spirochete protoplasmic cylinders were seen inside a single common outer membrane. A distinctive granulated cytoplasm in which the granules are of similar diameter (20-32 nanometers) to that of the flagella (26 nanometers) was present. Granule diameters were measured in thin section and in negatively-stained whole-mount preparations. Based on their ultrastructure, large size, variable diameter, number of flagella (3 to 6), and phototactic behavior these unique spirochetes are formally named Spirosymplokos deltaeiberi. Under anoxic (or low oxygen) conditions they formed blooms in mixed culture in media selective for spirochetes. Cellobiose was the major carbon source in 80% seawater, the antibiotic rifampicin was added, mat from the original field site was present and tubes were incubated in the light at from 18-31 degrees C. Within 1-2 weeks populations of the large spirochete developed at 25 degrees C but they could not be transferred to fresh medium.

  12. 3-nitro-1,2,4-triazol-5-one, a less sensitive explosive

    DOEpatents

    Lee, Kien-Yin; Coburn, Michael D.

    1988-01-01

    A less sensitive explosive, 3-nitro-1,2,4-triazol-5-one. The compound 3-nitro-1,2,4-triazol-5-one (NTO) has a crystal density of 1.93 g/cm.sup.3 and calculated detonation velocity and pressure equivalent to those of RDX. It can be prepared in high yield from inexpensive starting materials in a safe synthesis. Results from initial small-scale sensitivity tests indicate that NTO is less sensitive than RDX and HMX in all respects. A 4.13 cm diameter, unconfined plate-dent test at 92% of crystal density gave the detonation pressure predicted for NTO by the BKW calculation.

  13. The same-source parallel MM{sub 5}.

    SciTech Connect

    Michalakes, J.

    1999-08-23

    The set of architectures available to users of the Penn State/NCAR MM5 has been expanded to included distributed-memory parallel computers, providing cost-effective scalable performance and memory capacity for large problem sizes. The same-source approach uses high-level parallel library and source-translation technology for adapting MM5, simplifying maintenance and allowing new physics modules to be incorporated without modification. The approach facilitates maintenance of the DM-parallel option to MM5 as an option within the official version, rather than as a separate stand-alone version. As a result, the DM-parallel option to MM5 (now at Version 3.1) has been a part of six subsequent model releases since MM5 Version 2.8 in March 1998. The same-source approach is applicable to other, similarly constructed codes when there is a need or desire to develop the code for distributed memory parallel machines without impacting the pre-existing source code. The approach is also compatible with pre-existing loop-level multithreading directives so that the code will run in distributed-memory/shared-memory mode on SMP clusters.

  14. CMOS mm-wave transceivers for Gbps wireless communication

    NASA Astrophysics Data System (ADS)

    Baoyong, Chi; Zheng, Song; Lixue, Kuang; Haikun, Jia; Xiangyu, Meng; Zhihua, Wang

    2016-07-01

    The challenges in the design of CMOS millimeter-wave (mm-wave) transceiver for Gbps wireless communication are discussed. To support the Gbps data rate, the link bandwidth of the receiver/transmitter must be wide enough, which puts a lot of pressure on the mm-wave front-end as well as on the baseband circuit. This paper discusses the effects of the limited link bandwidth on the transceiver system performance and overviews the bandwidth expansion techniques for mm-wave amplifiers and IF programmable gain amplifier. Furthermore, dual-mode power amplifier (PA) and self-healing technique are introduced to improve the PA's average efficiency and to deal with the process, voltage, and temperature variation issue, respectively. Several fully-integrated CMOS mm-wave transceivers are also presented to give a short overview on the state-of-the-art mm-wave transceivers. Project supported in part by the National Natural Science Foundation of China (No. 61331003).

  15. Taming the 1.2 m Telescope

    NASA Astrophysics Data System (ADS)

    Griffin, S.; Edwards, M.; Greenwald, D.; Kono, D.; Liang, D.; Lohnes, K.; Wright, V.; Spillar, E.

    2013-09-01

    Achievable residual jitter on the 1.2 m telescope at MSSS shown in Figure 1 has historically been limited to 10-20 arc-sec. peak in moderate wind conditions due to the combination of the dynamics associated with the twin telescopes on the common declination axis shaft, and the related control system behavior. Figure 1 1.2 m Telescope The lightly damped, low frequency fundamental vibration mode shape of the telescopes rotating out of phase on the common declination axis shaft severely degraded the performance of the prior controllers. This vibration mode is easily excited by external forces such as wind loading and internal torque commands from the mount control system. The relatively poor historic performance was due to a combination of the low error rejection of external disturbances, and the controller exciting the mode. A radical new approach has been implemented that has resulted in a decrease of jitter to less than 1 arcsec under most conditions. The new approach includes minor hardware modifications to provide active damping with accelerometers as feedback sensors. This architecture has allowed a bandwidth increase of almost an order of magnitude and eliminated the large amplitude motions at the mode natural frequency, resulting in much improved pointing and jitter performance. A representative comparison of historical versus new architecture performance is shown in Figure 2 for the declination axis.

  16. A High-Resolution Endoscope of Small Diameter Using Electromagnetically Vibration of Single Fiber

    NASA Astrophysics Data System (ADS)

    Matsunaga, Tadao; Hino, Ryunosuke; Makishi, Wataru; Esashi, Masayoshi; Haga, Yoichi

    For high resolution visual inspection in the narrow space of the human body, small diameter endoscope has been developed which utilize electromagnetically vibration of single fiber. Thin endoscopes are effective for inspection in the narrow space of the human body, for example, in the blood vessel, lactiferous duct for detection infiltration of breast cancer, and periodontal gap between gingiva and tooth. This endoscope consists of single optical fiber and photofabricated driving coils. A collimator lens and a cylindrical permanent magnet are fixed on the optical fiber, and the tilted driving coils have been patterned on a 1.08 mm outer diameter thin tube. The fiber is positioned at the center of the tube which is patterned the coils. When an electrical alternating current at the resonance frequency is supplied to the coils, the permanent magnet which is fixed to the fiber is vibrated electromagnetically and scanned one or two dimensionally. This paper reports small diameter endoscope by using electromagnetically vibration of single fiber. Optical coherence tomography imaging has also been carried out with the fabricated endoscope and cross-section image of sub-surface skin of thumb was observed.

  17. Optimization of laser-induced breakdown spectroscopy for coal powder analysis with different particle flow diameters

    NASA Astrophysics Data System (ADS)

    Yao, Shunchun; Xu, Jialong; Dong, Xuan; Zhang, Bo; Zheng, Jianping; Lu, Jidong

    2015-08-01

    The on-line measurement of coal is extremely useful for emission control and combustion process optimization in coal-fired plant. Laser-induced breakdown spectroscopy was employed to directly analyze coal particle flow. A set of tapered tubes were proposed for beam-focusing the coal particle flow to different diameters. For optimizing the measurement of coal particle flow, the characteristics of laser-induced plasma, including optical breakdown, the relative standard deviation of repeated measurement, partial breakdown spectra ratio and line intensity, were carefully analyzed. The comparison of the plasma characteristics among coal particle flow with different diameters showed that air breakdown and the random change in plasma position relative to the collection optics could significantly influence on the line intensity and the reproducibility of measurement. It is demonstrated that the tapered tube with a diameter of 5.5 mm was particularly useful to enrich the coal particles in laser focus spot as well as to reduce the influence of air breakdown and random changes of plasma in the experiment.

  18. The effect of the impactor diameter and temperature on low velocity impact behavior of CFRP laminates

    NASA Astrophysics Data System (ADS)

    Evci, C.; Uyandıran, I.

    2017-02-01

    Impact damage is one of the major concerns that should be taken into account with the new aircraft and spacecraft structures which employ ever-growing use of composite materials. Considering the thermal loads encountered at different altitudes, both low and high temperatures can affect the properties and impact behavior of composite materials. This study aims to investigate the effect of temperature and impactor diameter on the impact behavior and damage development in balanced and symmetrical CFRP laminates which were manufactured by employing vacuum bagging process with autoclave cure. Instrumented drop-weight impact testing system is used to perform the low velocity impact tests in a range of temperatures ranged from 60 down to -50 °C. Impact tests for each temperature level were conducted using three different hemispherical impactor diameters varying from 10 to 20 mm. Energy profile method is employed to determine the impact threshold energies for damage evolution. The level of impact damage is determined from the dent depth on the impacted face and delamination damage detected using ultrasonic C-Scan technique. Test results reveal that the threshold of penetration energy, main failure force and delamination area increase with impactor diameter at all temperature levels. No clear influence of temperature on the critical force thresholds could be derived. However, penetration threshold energy decreased as the temperature was lowered. Drop in the penetration threshold was more obvious with quite low temperatures. Delamination damage area increased while the temperature decreased from +60 °C to -50 °C.

  19. Diameter distribution estimation with laser scanning based multisource single tree inventory

    NASA Astrophysics Data System (ADS)

    Kankare, Ville; Liang, Xinlian; Vastaranta, Mikko; Yu, Xiaowei; Holopainen, Markus; Hyyppä, Juha

    2015-10-01

    Tree detection and tree species recognition are bottlenecks of the airborne remote sensing-based single tree inventories. The effect of these factors in forest attribute estimation can be reduced if airborne measurements are aided with tree mapping information that is collected from the ground. The main objective here was to demonstrate the use of terrestrial laser scanning-derived (TLS) tree maps in aiding airborne laser scanning-based (ALS) single tree inventory (multisource single tree inventory, MS-STI) and its capability in predicting diameter distribution in various forest conditions. Automatic measurement of TLS point clouds provided the tree maps and the required reference information from the tree attributes. The study area was located in Evo, Finland, and the reference data was acquired from 27 different sample plots with varying forest conditions. The workflow of MS-STI included: (1) creation of automatic tree map from TLS point clouds, (2) automatic diameter at breast height (DBH) measurement from TLS point clouds, (3) individual tree detection (ITD) based on ALS, (4) matching the ITD segments to the field-measured reference, (5) ALS point cloud metric extraction from the single tree segments and (6) DBH estimation based on the derived metrics. MS-STI proved to be accurate and efficient method for DBH estimation and predicting diameter distribution. The overall accuracy (root mean squared error, RMSE) of the DBH was 36.9 mm. Results showed that the DBH accuracy decreased if the tree density (trees/ha) increased. The highest accuracies were found in old-growth forests (tree densities less than 500 stems/ha). MS-STI resulted in the best accuracies regarding Norway spruce (Picea abies (L.) H. Karst.)-dominated forests (RMSE of 29.9 mm). Diameter distributions were predicted with low error indices, thereby resulting in a good fit compared to the reference. Based on the results, diameter distribution estimation with MS-STI is highly dependent on the forest

  20. New Methods for Exploring QM:MM Potential Energy Landscapes

    NASA Astrophysics Data System (ADS)

    Hratchian, Hrant P.

    2010-06-01

    In recent years, the applicability of quantum chemical methods for large system studies has been greatly enhanced by the development of hybrid QM:MM techniques. Despite these advancements, exploring the associated potential energy surfaces continues to present two key challenges. First, the QM energy and derivative evaluations may be too costly for simulations; and second, the system size for many QM:MM cases are too large to effectively store or use second-order information, an approach often used in QM studies to allow for larger integration steps and fewer QM evaluations of the potential energy surface. Our most recent work is focused on overcoming both computational bottlenecks. Using surface fitting models together with direct Hessian-vector and diagonalization algorithms, we are developing models that can accurately and efficiently explore QM:MM potential energy landscapes for very large systems. Our current development status and results from initial applications will be described.

  1. QM/MM X-ray Refinement of Zinc Metalloenzymes

    PubMed Central

    Li, Xue; Hayik, Seth A.; Merz, Kenneth M.

    2010-01-01

    Zinc metalloenzymes play an important role in biology. However, due to the limitation of molecular force field energy restraints used in X-ray refinement at medium or low resolutions, the precise geometry of the zinc coordination environment can be difficult to distinguish from ambiguous electron density maps. Due to the difficulties involved in defining accurate force fields for metal ions, the QM/MM (Quantum-Mechanical /Molecular-Mechanical) method provides an attractive and more general alternative for the study and refinement of metalloprotein active sites. Herein we present three examples that indicate that QM/MM based refinement yields a superior description of the crystal structure based on R and Rfree values and on the inspection of the zinc coordination environment. It is concluded that QM/MM refinement is a useful general tool for the improvement of the metal coordination sphere in metalloenzyme active sites. PMID:20116858

  2. A new noninvasive method for the accurate and precise assessment of varicose vein diameters.

    PubMed

    Baldassarre, Damiano; Pustina, Linda; Castelnuovo, Samuela; Bondioli, Alighiero; Carlà, Matteo; Sirtori, Cesare R

    2003-01-01

    The feasibility and reproducibility of a new ultrasonic method for the direct assessment of maximal varicose vein diameter (VVD) were evaluated. A study was also performed to demonstrate the capacity of the method to detect changes in venous diameter induced by a pharmacologic treatment. Patients with varicose vein disease were recruited. A method that allows the precise positioning of patient and transducer and performance of scans in a gel-bath was developed. Maximal VVD was recorded both in the standing and supine positions. The intraassay reproducibility was determined by replicate scans made within 15 minutes in both positions. The interobserver variability was assessed by comparing VVDs measured during the first phase baseline examination with those obtained during baseline examinations in the second phase of the study. The error in reproducibility of VVD determinations was 5.3% when diameters were evaluated in the standing position and 6.4% when assessed in the supine position. The intramethod agreement was high, with a bias between readings of 0.06 +/- 0.18 mm and of -0.02 +/- 0.19 mm, respectively, in standing and supine positions. Correlation coefficients were better than 0.99 in both positions. The method appears to be sensitive enough to detect small changes in VVDs induced by treatments. The proposed technique provides a tool of potential valid use in the detection and in vivo monitoring of VVD changes in patients with varicose vein disease. The method offers an innovative approach to obtain a quantitative assessment of varicose vein progression and of treatment effects, thus providing a basis for epidemiologic surveys.

  3. 450mm wafer patterning with jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Thompson, Ecron; Hellebrekers, Paul; Hofemann, Paul; LaBrake, Dwayne L.; Resnick, Douglas J.; Sreenivasan, S. V.

    2013-09-01

    The next step in the evolution of wafer size is 450mm. Any transition in sizing is an enormous task that must account for fabrication space, environmental health and safety concerns, wafer standards, metrology capability, individual process module development and device integration. For 450mm, an aggressive goal of 2018 has been set, with pilot line operation as early as 2016. To address these goals, consortiums have been formed to establish the infrastructure necessary to the transition, with a focus on the development of both process and metrology tools. Central to any process module development, which includes deposition, etch and chemical mechanical polishing is the lithography tool. In order to address the need for early learning and advance process module development, Molecular Imprints Inc. has provided the industry with the first advanced lithography platform, the Imprio® 450, capable of patterning a full 450mm wafer. The Imprio 450 was accepted by Intel at the end of 2012 and is now being used to support the 450mm wafer process development demands as part of a multi-year wafer services contract to facilitate the semiconductor industry's transition to lower cost 450mm wafer production. The Imprio 450 uses a Jet and Flash Imprint Lithography (J-FILTM) process that employs drop dispensing of UV curable resists to assist high resolution patterning for subsequent dry etch pattern transfer. The technology is actively being used to develop solutions for markets including NAND Flash memory, patterned media for hard disk drives and displays. This paper reviews the recent performance of the J-FIL technology (including overlay, throughput and defectivity), mask development improvements provided by Dai Nippon Printing, and the application of the technology to a 450mm lithography platform.

  4. Comparison of the Efficacies of 0.94 mm and Double Silicone Tubes for Treatment of Canalicular Obstruction

    PubMed Central

    Choi, Seong Chan; Choi, Hye Sun; Jang, Jae Woo; Kim, Sung Joo

    2017-01-01

    Purpose To compare the clinical effects of the single wide-diameter bicanalicular silicone tube and the double bicanalicular silicone tube in endonasal dacryocystorhinostomy (DCR) with canalicular trephinization for canalicular obstruction. Methods We retrospectively reviewed the records of 121 patients with monocanalicular or common canalicular obstruction who had undergone endonasal DCR with random bicanalicular insertion of either double silicone tubes (insertion of two tubes into each canaliculus) or a single wide-diameter (0.94 mm) silicone tube. The tubes were removed at around 3 months after surgery. Results This study included 79 eyes of 61 patients in the double-tube intubation group and 68 eyes of 60 patients in the single wide-diameter tube intubation group. Anatomical success, evaluated by syringing, was achieved in 72 of the 79 eyes (91.1%) in the double-tube intubation group and 60 of the 68 eyes (88.2%) in the single wide-diameter tube intubation group. Functional success was achieved in 65 of the 79 eyes (82.3%) in the double-tube intubation group and 61 of the 68 (89.7%) eyes in the single wide-diameter tube intubation group. There were no significant differences in the success rates of surgery between the two groups. One patient in the double-tube intubation group underwent conjunctivodacryocystorhinostomy (CDCR) and two in the wide-diameter tube intubation group underwent CDCR or reintubation to treat recurrence. Conclusions Intubation using a single wide-diameter tube during endonasal DCR is as effective as double-tube intubation for the treatment of canalicular obstruction, with a lower rate of complications such as inflammation or patient discomfort. PMID:28243017

  5. Third-body abrasive wear challenge of 32 mm conventional and 44 mm highly crosslinked polyethylene liners in a hip simulator model.

    PubMed

    Sorimachi, T; Clarke, I C; Williams, P A; Gustafson, A; Yamamoto, K

    2009-07-01

    Hip simulator studies have shown that wear in the polyethylene liners used for total hip replacements increased with the larger-diameter femoral balls and could also be exacerbated by third-body abrasion. However, they also indicated that the more highly cross-linked polyethylene (HXPE) bearings were more wear resistant than conventional polyethylene (CXPE) bearings. Unfortunately the HXPE bearings appeared to be particularly sensitive to adverse wear conditions. One simulator study in particular indicated that poly(methyl methacrylate) (PMMA) debris increased wear sixfold by means of two-body abrasive interactions rather than the supposed third-body abrasion or roughening effects of the Co-Cr surfaces. There has been no confirmation of such novel theories. Therefore the goal of this study was to investigate the sensitivity of large-diameter HXPE bearings to the third-body PMMA wear challenge in a hip simulator model. An orbital hip simulator was used in standard test mode with a physiological load profile. The 32 mm control liners were machined from moulded GUR1050 and gamma irradiated to 35 kGy under nitrogen (CXPE). The 44 mm liners were also from moulded blanks, gamma irradiated to 75 kGy, machined to shape, given a proprietary heat treatment, and sterilized by gas plasma (HXPE). As in the published simulator model, the study was conducted in three phases. In phase 1, all cups were run in standard ('clean') lubricant for 1.5 x 10(6) cycles duration. In phase 2, three CXPE cups and six HXPE cups were run for 2 x 10(6) cycles with a slurry of PMMA particles added to the lubricant. In phase 3, the implants were again run in 'clean' lubricant for 2 x 10(6) cycles duration. In addition, three HXPE cups were run as wear controls for 5.5 x 10(6) cycles duration in clean lubricant. In phase-1, the HXPE liners demonstrated twelvefold reduced wear compared with the CXPE controls. The 32 mm and 44 mm Co-Cr balls were judged of comparable roughnesses. However, the surface

  6. Continuous transformation of a -1/2 wedge disclination line to a +1/2 one

    NASA Astrophysics Data System (ADS)

    Fukuda, Jun-Ichi

    2010-04-01

    It is known that, in the order-parameter space S2/Z2 (a typical example being a uniaxial nematic liquid crystal in three dimensions), a -1/2 wedge disclination line and a +1/2 one are topologically equivalent and can thus be transformed continuously into each other. Here we report the realization of this transformation in a simulation of a cholesteric blue phase under an electric field.

  7. Numerical investigation of scale effect of various injection diameters on interaction in cold kerosene-fueled supersonic flow

    NASA Astrophysics Data System (ADS)

    Zhu, Lin; Qi, Yin-Yin; Liu, Wei-Lai; Xu, Bao-Jian; Ge, Jia-Ru; Xuan, Xiang-Chun; Jen, Tien-Chien

    2016-12-01

    The incident shock wave generally has a strong effect on the transversal injection field in cold kerosene-fueled supersonic flow, possibly due to its affecting the interaction between incoming flow and fuel through various operation conditions. This study is to address scale effect of various injection diameters on the interaction between incident shock wave and transversal cavity injection in a cold kerosene-fueled scramjet combustor. The injection diameters are separately specified as from 0.5 to 1.5 mm in 0.5 mm increments when other performance parameters, including the injection angle, velocity and pressure drop are all constant. A combined three dimensional Couple Level Set & Volume of Fluids (CLSVOF) approach with an improved K-H & R-T model is used to characterize penetration height, span expansion area, angle of shock wave and sauter mean diameter (SMD) distribution of the kerosene droplets with/without considering evaporation. Our results show that the injection orifice surely has a great scale effect on the transversal injection field in cold kerosene-fueled supersonic flows. Our findings show that the penetration depth, span angle and span expansion area of the transverse cavity jet are increased with the injection diameter, and that the kerosene droplets are more prone to breakup and atomization at the outlet of the combustor for the orifice diameter of 1.5 mm. The calculation predictions are compared against the reported experimental measurements and literatures with good qualitative agreement. The simulation results obtained in this study can provide the evidences for better understanding the underlying mechanism of kerosene atomization in cold supersonic flow and scramjet design improvement.

  8. [Femoropopliteal bypass above the knee-joint fissure by means of a vascular prosthesis made of PTFE: choosing an appropriate diameter of the prosthesis].

    PubMed

    Pokrovskiĭ, A V; Dan, V N; Zotikov, A E; Chupin, A V; Shubin, A A; Bogatov, Iu P; Tedeev, A K

    2007-01-01

    Presented herein are the outcomes of a total of 80 operations of femoropopliteal grafting above the knee-joint fissure, carried out using a vascular prosthesis made of polytetrafluoroethylene (PTFE) in patients diagnosed with atherosclerotic lesions of the arteries of the lower extremities over the period between February 1995 and December 2005 at the Department of Vascular Surgery of the A. V. Vishnevsky Institute of Surgery of the Russian Academy of Medical Sciences. Fifty percent of the patients were operated on for grade II B ischemia, while 13.7% of the patients suffered from grade III ischaemia of the lower limb, and 29 (36.3%) subjects were found to have grade IV ischaemia. The condition of the distal bed was considered in 41.2% of the patients, being defined as in 48.5%, and as "poor" in 10.3%. The operative intervention was carried out according to the conventionally accepted technique. 50% of the reconstructions were performed using the prosthesis 8 mm in diameter, and 50% - using that measuring 6 mm in diameter. A statistically significant impact of the diameter of the prosthesis used on the patency of the graft in the remote postoperative period was revealed: with the prosthesis 8-mm in diameter, the patency after 12, 30 and 60 months amounted to 93%, 64% and 51%, respectively, while with the transplant measuring 6 mm in diameter, these indices at the above-mentioned time intervals did not exceed 62%, 44% and 31%, respectively (P=0.004).

  9. 1,2-hydroxypyridonates as contrast agents for magnetic resonance imaging: TREN-1,2-HOPO.

    PubMed

    Jocher, Christoph J; Moore, Evan G; Xu, Jide; Avedano, Stefano; Botta, Mauro; Aime, Silvio; Raymond, Kenneth N

    2007-10-29

    1,2-Hydroxypyridinones (1,2-HOPO) form very stable lanthanide complexes that may be useful as contrast agents for magnetic resonance imaging (MRI). X-ray diffraction of single crystals established that the solid-state structures of the Eu(III) and the previously reported [Inorg. Chem. 2004, 43, 5452] Gd(III) complex are identical. The recently discovered sensitizing properties of 1,2-HOPO chelates for Eu(III) luminescence [J. Am. Chem. Soc. 2006, 128, 10 067] allow for direct measurement of the number of water molecules coordinated to the metal center. Fluorescence measurements of the Eu(III) complex corroborate that, in solution, two water molecules coordinate the lanthanide (q = 2) as proposed from the analysis of NMRD profiles. In addition, fluorescence measurements have verified the anion binding interactions of lanthanide TREN-1,2-HOPO complexes in solution, studied by relaxivity, revealing only very weak oxalate binding (KA = 82.7 +/- 6.5 M-1). Solution thermodynamic studies of the metal complex and free ligand have been carried out using potentiometry, spectrophotometry, and fluorescence spectroscopy. The metal ion selectivity of TREN-1,2-HOPO supports the feasibility of using 1,2-HOPO ligands for selective lanthanide binding [pGd = 19.3 (2), pZn = 15.2 (2), pCa = 8.8 (3)].

  10. Evaluation function of drinking ease from aluminum beverage bottles relative to optimum bottle opening diameter and beverage type.

    PubMed

    Chihara, Takanori; Yamazaki, Koetsu

    2012-01-01

    In recent years, aluminum beverage bottles having screw tops with opening diameters of 28 and 38 mm have been launched in the Japanese market in keeping with the modern-day drinking habits of consumers. Although Japanese consumers are familiar with such bottles, a majority of them feel that the 28 mm opening is too small and the 38 mm opening is too large. Therefore, we felt the need to develop a method for evaluating consumer feelings when they drink a beverage directly from the bottle opening. For this purpose, we propose an evaluation function of drinking ease that calculates the optimum opening diameter of the bottle. From results of our previous study, we know that there exists an ideal volume of beverage flowing into the mouth, at which consumers feel most comfortable while drinking directly from bottles. Therefore, we define the evaluation function of drinking ease in terms of the difference between the actual volume of fluid in the mouth and the expected ideal volume. If this difference is small, consumers probably feel comfortable while drinking the beverage. We consider a design variable, i.e., the opening diameter, and two state variables, i.e., the volume of beverage remaining in the bottle and the height of consumers, and construct the response surface of the evaluation function by using radial basis function networks. In addition, for investigating the influence of beverage type on the evaluation function, we select green tea and a carbonated beverage (Coke) as test beverages. Results of optimization of the proposed function show that when the opening diameters are 35.4 mm and 34.4 mm in the case of green tea and Coke, respectively, the actual volume of fluid in the mouth is closest to the ideal volume and the participants feel most comfortable. These results are in agreement with results of our previous study that an opening diameter of 33 mm is optimum for young Japanese adults. Thus, we confirm that the proposed function is accurate; it can be used

  11. Automatic detection of cardiac cycle and measurement of the mitral annulus diameter in 4D TEE images

    NASA Astrophysics Data System (ADS)

    Graser, Bastian; Hien, Maximilian; Rauch, Helmut; Meinzer, Hans-Peter; Heimann, Tobias

    2012-02-01

    Mitral regurgitation is a wide spread problem. For successful surgical treatment quantification of the mitral annulus, especially its diameter, is essential. Time resolved 3D transesophageal echocardiography (TEE) is suitable for this task. Yet, manual measurement in four dimensions is extremely time consuming, which confirms the need for automatic quantification methods. The method we propose is capable of automatically detecting the cardiac cycle (systole or diastole) for each time step and measuring the mitral annulus diameter. This is done using total variation noise filtering, the graph cut segmentation algorithm and morphological operators. An evaluation took place using expert measurements on 4D TEE data of 13 patients. The cardiac cycle was detected correctly on 78% of all images and the mitral annulus diameter was measured with an average error of 3.08 mm. Its full automatic processing makes the method easy to use in the clinical workflow and it provides the surgeon with helpful information.

  12. Application of face centred central composite design to optimise compression force and tablet diameter for the formulation of mechanically strong and fast disintegrating orodispersible tablets.

    PubMed

    Pabari, Ritesh M; Ramtoola, Zebunnissa

    2012-07-01

    A two factor, three level (3(2)) face centred, central composite design (CCD) was applied to investigate the main and interaction effects of tablet diameter and compression force (CF) on hardness, disintegration time (DT) and porosity of mannitol based orodispersible tablets (ODTs). Tablet diameters of 10, 13 and 15 mm, and CF of 10, 15 and 20 kN were studied. Results of multiple linear regression analysis show that both the tablet diameter and CF influence tablet characteristics. A negative value of regression coefficient for tablet diameter showed an inverse relationship with hardness and DT. A positive value of regression coefficient for CF indicated an increase in hardness and DT with increasing CF as a result of the decrease in tablet porosity. Interestingly, at the larger tablet diameter of 15 mm, while hardness increased and porosity decreased with an increase in CF, the DT was resistant to change. The optimised combination was a tablet of 15 mm diameter compressed at 15 kN showing a rapid DT of 37.7s and high hardness of 71.4N. Using these parameters, ODTs containing ibuprofen showed no significant change in DT (ANOVA; p>0.05) irrespective of the hydrophobicity of the ibuprofen.

  13. Reproducibility and accuracy of optic nerve sheath diameter assessment using ultrasound compared to magnetic resonance imaging

    PubMed Central

    2013-01-01

    Background Quantification of the optic nerve sheath diameter (ONSD) by transbulbar sonography is a promising non-invasive technique for the detection of altered intracranial pressure. In order to establish this method as follow-up tool in diseases with intracranial hyper- or hypotension scan-rescan reproducibility and accuracy need to be systematically investigated. Methods The right ONSD of 15 healthy volunteers (mean age 24.5 ± 0.8 years) were measured by both transbulbar sonography (9 – 3 MHz) and 3 Tesla MRI (half-Fourier acquisition single-shot turbo spin-echo sequences, HASTE) 3 and 5 mm behind papilla. All volunteers underwent repeated ultrasound and MRI examinations in order to assess scan-rescan reproducibility and accuracy. Moreover, inter- and intra-observer variabilities were calculated for both techniques. Results Scan-rescan reproducibility was robust for ONSD quantification by sonography and MRI at both depths (r > 0.75, p ≤ 0.001, mean differences < 2%). Comparing ultrasound- and MRI-derived ONSD values, we found acceptable agreement between both methods for measurements at a depth of 3 mm (r = 0.72, p = 0.002, mean difference < 5%). Further analyses revealed good inter- and intra-observer reliability for sonographic measurements 3 mm behind the papilla and for MRI at 3 and 5 mm (r > 0.82, p < 0.001, mean differences < 5%). Conclusions Sonographic ONSD quantification 3 mm behind the papilla can be performed with good reproducibility, measurement accuracy and observer agreement. Thus, our findings emphasize the feasibility of this technique as a non-invasive bedside tool for longitudinal ONSD measurements. PMID:24289136

  14. Advanced ACTPol Multichroic Polarimeter Array Fabrication Process for 150 mm Wafers

    NASA Technical Reports Server (NTRS)

    Duff, S. M.; Austermann, J.; Beall, J. A.; Becker, D.; Datta, R.; Gallardo, P. A.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Pappas, C. G.; Salatino, M.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-01-01

    Advanced ACTPol (AdvACT) is a third-generation cosmic microwave background receiver to be deployed in 2016 on the Atacama Cosmology Telescope (ACT). Spanning five frequency bands from 25 to 280 GHz and having just over 5600 transition-edge sensor (TES) bolometers, this receiver will exhibit increased sensitivity and mapping speed compared to previously fielded ACT instruments. This paper presents the fabrication processes developed by NIST to scale to large arrays of feedhorn-coupled multichroic AlMn-based TES polarimeters on 150-mm diameter wafers. In addition to describing the streamlined fabrication process which enables high yields of densely packed detectors across larger wafers, we report the details of process improvements for sensor (AlMn) and insulator (SiN(sub x)) materials and microwave structures, and the resulting performance improvements.

  15. Advanced ACTPol Multichroic Polarimeter Array Fabrication Process for 150 mm Wafers

    NASA Astrophysics Data System (ADS)

    Duff, S. M.; Austermann, J.; Beall, J. A.; Becker, D.; Datta, R.; Gallardo, P. A.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Pappas, C. G.; Salatino, M.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-08-01

    Advanced ACTPol (AdvACT) is a third-generation cosmic microwave background receiver to be deployed in 2016 on the Atacama Cosmology Telescope (ACT). Spanning five frequency bands from 25 to 280 GHz and having just over 5600 transition-edge sensor (TES) bolometers, this receiver will exhibit increased sensitivity and mapping speed compared to previously fielded ACT instruments. This paper presents the fabrication processes developed by NIST to scale to large arrays of feedhorn-coupled multichroic AlMn-based TES polarimeters on 150-mm diameter wafers. In addition to describing the streamlined fabrication process which enables high yields of densely packed detectors across larger wafers, we report the details of process improvements for sensor (AlMn) and insulator (SiN_x) materials and microwave structures, and the resulting performance improvements.

  16. Design and performance of Sandia's contactless coilgun for 50 mm projectiles

    NASA Astrophysics Data System (ADS)

    Kaye, Ronald J.; Cnare, Eugene C.; Cowan, M.; Duggin, Billy W.; Lipinski, Ronald J.; Marder, Barry M.; Douglas, Gary M.; Shimp, Kenneth J.

    1991-10-01

    A multi-stage, contactless coilgun is being designed to demonstrate the applicability of this technology to accelerate nominal 50 mm (2 inch) diameter projectiles to velocities of 3 km/s. Forty stages of this design (Phase 1 coilgun) will provide a testbed for coil designs and system components while accelerating 200 to 400 gram projectiles to 1 km/s. We have successfully qualified the Phase 1 gun by operating 40 stages at half energy (10 kJ stored/stage) accelerating 340 gram, room-temperature, aluminum-armature projectiles to 406 m/s. We expect to accelerate 200 gram projectiles cooled to -196 C to three times this velocity when operating at full energy. This paper describes the design and performance of the Phase 1 coilgun and includes discussion of coil development, projectile design, capacitor banks, firing system, and integration.

  17. Estimating the diameter of airways susceptible for collapse using crackle sound.

    PubMed

    Majumdar, Arnab; Hantos, Zoltán; Tolnai, József; Parameswaran, Harikrishnan; Tepper, Robert; Suki, Béla

    2009-11-01

    Airways that collapse during deflation generate a crackle sound when they reopen during subsequent reinflation. Since each crackle is associated with the reopening of a collapsed airway, the likelihood of an airway to be a crackle source is identical to its vulnerability to collapse. To investigate this vulnerability of airways to collapse, crackles were recorded during the first inflation of six excised rabbit lungs from the collapsed state, and subsequent reinflations from 5, 2, 1, and 0 cmH(2)O end-expiratory pressure levels. We derived a relationship between the amplitude of a crackle sound at the trachea and the generation number (n) of the source airway where the crackle was generated. Using an asymmetrical tree model of the rabbit airways with elastic walls, airway vulnerability to collapse was also determined in terms of airway diameter D. During the reinflation from end-expiratory pressure = 0 cmH(2)O, the most vulnerable airways were estimated to be centered at n = 12 with a peak. Vulnerability in terms of D ranged between 0.1 and 1.3 mm, with a peak at 0.3 mm. During the inflation from the collapsed state, however, vulnerability was much less localized to a particular n or D, with maximum values of n = 8 and D = 0.75 mm. Numerical simulations using a tree model that incorporates airway opening and closing support these conclusions. Thus our results indicate that there are airways of a given range of diameters that can become unstable during deflation and vulnerable to collapse and subsequent injury.

  18. A Biomechanical Comparison of Three 1.5-mm Plate and Screw Configurations and a Single 2.0-mm Plate for Internal Fixation of a Mandibular Condylar Fracture

    PubMed Central

    Aquilina, Peter; Parr, William C.H.; Chamoli, Uphar; Wroe, Stephen; Clausen, Philip

    2014-01-01

    The most stable pattern of internal fixation for mandibular condyle fractures is an area of ongoing discussion. This study investigates the stability of three patterns of plate fixation using readily available, commercially pure titanium implants. Finite element models of a simulated mandibular condyle fracture were constructed. The completed models were heterogeneous in bone material properties, contained approximately 1.2 million elements and incorporated simulated jaw adducting musculature. Models were run assuming linear elasticity and isotropic material properties for bone. No human subjects were involved in this investigation. The stability of the simulated condylar fracture reduced with the different implant configurations, and the von Mises stresses of a 1.5-mm X-shaped plate, a 1.5-mm rectangular plate, and a 1.5-mm square plate (all Synthes (Synthes GmbH, Zuchwil, Switzerland) were compared. The 1.5-mm X plate was the most stable of the three 1.5-mm profile plate configurations examined and had comparable mechanical performance to a single 2.0-mm straight four-hole plate. This study does not support the use of rectangular or square plate patterns in the open reduction and internal fixation of mandibular condyle fractures. It does provide some support for the use of a 1.5-mm X plate to reduce condylar fractures in selected clinical cases. PMID:25136411

  19. Compositional Variation in Large-Diameter Low-Albedo asteroids

    NASA Astrophysics Data System (ADS)

    Vilas, F.; Jarvis, K. S.; Thibault, C. A.; Sawyer, S. R.

    2000-12-01

    Age dating of meteorites indicates that the Solar System was subjected to a major heating event 4.5 Gyr ago. Models of the effects of heating by electromagnetic induction or decay of short-lived radionuclides combined with models of the early collisional history of the Solar System after Jupiter's formation indicate that asteroids observed today can be divided into two groups by diameter. Those asteroids having diameters greater than 100 km were mixed by multiple collisions but remain as gravitationally bound rubble piles. Asteroids with diameters less than 100 km should show more compositional diversity. Vilas and Sykes (1996, Icarus, 124) have shown using ECAS photometry that this compositional difference exists. The larger diameter group should be individually homogenous, with spectral differences showing the combined effects of a primordial compositional gradient in the asteroid belt with thermal metamorphism. We address the significance of 36 rotationally-resolved spectra of larger-diameter low-albedo asteroids of the C class (and subclasses B, F, G) and P class in the visible and Near-IR spectral regions. This work was supported by the NASA Planetary Astronomy program.

  20. Memory, emotion, and pupil diameter: Repetition of natural scenes.

    PubMed

    Bradley, Margaret M; Lang, Peter J

    2015-09-01

    Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes.

  1. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum.

    PubMed

    Sepehrband, Farshid; Alexander, Daniel C; Clark, Kristi A; Kurniawan, Nyoman D; Yang, Zhengyi; Reutens, David C

    2016-01-01

    Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy), or to infer them indirectly (e.g., using diffusion-weighted MRI). The gamma distribution is a common choice for this purpose (particularly for the inferential approach) because it resembles the distribution profile of measured axon diameters which has been consistently shown to be non-negative and right-skewed. In this study we compared a wide range of parametric probability distribution functions against empirical data obtained from electron microscopy images. We observed that the gamma distribution fails to accurately describe the main characteristics of the axon diameter distribution, such as location and scale of the mode and the profile of distribution tails. We also found that the generalized extreme value distribution consistently fitted the measured distribution better than other distribution functions. This suggests that there may be distinct subpopulations of axons in the corpus callosum, each with their own distribution profiles. In addition, we observed that several other distributions outperformed the gamma distribution, yet had the same number of unknown parameters; these were the inverse Gaussian, log normal, log logistic and Birnbaum-Saunders distributions.

  2. Two-dimensional wakes of a variable diameter cylinder

    NASA Astrophysics Data System (ADS)

    Yang, Wenchao; Stremler, Mark

    2016-11-01

    It is well known that periodic variations in the position of a circular cylinder can produce a variety of complex vortex wake patterns. We will discuss what we believe is the first investigation of the wake patterns produced by a stationary circular cylinder undergoing periodic variations in the cylinder diameter. In our experiments, cylinder variations are produced by oscillating a cone perpendicularly through a flowing soap film. The wake flow generates thickness variations in the thin soap film, allowing direct observation of wake patterns through visualization of interference fringes. We consider diameter variations ranging from 0.1 to 0.5 times the mean diameter, with the Reynolds number varying from 50 to 150. The frequency of the diameter's variation influences the wake patterns. When the variation frequency is negligible compared to the vortex shedding frequency, the wake is a quasi-steady representation of fixed cylinder shedding. We will discuss wake pattern bifurcations that occur as the variation frequency becomes comparable to the vortex shedding frequency. Comparisons will be made with the wake patterns generated by a constant-diameter circular cylinder forced to oscillate transverse to the free stream.

  3. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum

    PubMed Central

    Sepehrband, Farshid; Alexander, Daniel C.; Clark, Kristi A.; Kurniawan, Nyoman D.; Yang, Zhengyi; Reutens, David C.

    2016-01-01

    Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy), or to infer them indirectly (e.g., using diffusion-weighted MRI). The gamma distribution is a common choice for this purpose (particularly for the inferential approach) because it resembles the distribution profile of measured axon diameters which has been consistently shown to be non-negative and right-skewed. In this study we compared a wide range of parametric probability distribution functions against empirical data obtained from electron microscopy images. We observed that the gamma distribution fails to accurately describe the main characteristics of the axon diameter distribution, such as location and scale of the mode and the profile of distribution tails. We also found that the generalized extreme value distribution consistently fitted the measured distribution better than other distribution functions. This suggests that there may be distinct subpopulations of axons in the corpus callosum, each with their own distribution profiles. In addition, we observed that several other distributions outperformed the gamma distribution, yet had the same number of unknown parameters; these were the inverse Gaussian, log normal, log logistic and Birnbaum-Saunders distributions. PMID:27303273

  4. Brown dwarf disks with Herschel: Linking far-infrared and (sub)-mm fluxes

    NASA Astrophysics Data System (ADS)

    Daemgen, Sebastian; Natta, Antonella; Scholz, Alexander; Testi, Leonardo; Jayawardhana, Ray; Greaves, Jane; Eastwood, Daniel

    2016-10-01

    Brown dwarf disks are excellent laboratories to test our understanding of disk physics in an extreme parameter regime. In this paper we investigate a sample of 29 well-characterized brown dwarfs and very low-mass stars, for which Herschel far-infrared fluxes and (sub)-mm fluxes are available. We measured new Herschel/PACS fluxes for 11 objects and complement these with (sub)-mm data and Herschel fluxes from the literature. We analyze their spectral energy distributions in comparison with results from radiative transfer modeling. Fluxes in the far-infrared are strongly affected by the shape and temperature of the disk (and hence stellar luminosity), whereas the (sub)-mm fluxes mostly depend on disk mass. Nevertheless, there is a clear correlation between far-infrared and (sub)-mm fluxes. We argue that the link results from the combination of the stellar mass-luminosity relation and a scaling between disk mass and stellar mass. We find strong evidence of dust settling to the disk midplane. The spectral slopes between near- and far-infrared are mostly between -0.5 and -1.2 in our sample, which is comparable to more massive T Tauri stars; this may imply that the disk shapes are similar as well, although highly flared disks are rare among brown dwarfs. We find that dust temperatures in the range of 7-15 K, calculated with T ≈ 25 (L/L⊙)0.25 K, are appropriate for deriving disk masses from (sub)-mm fluxes for these low luminosity objects. About half of our sample hosts disks with at least one Jupiter mass, confirming that many brown dwarfs harbor sufficient material for the formation of Earth-mass planets in their midst. Herschel is a ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  5. Surgical Management of Tibial Plateau Fractures With 3.5 mm Simple Plates

    PubMed Central

    Bagherifard, Abolfazl; Jabalameli, Mahmoud; Hadi, Hosseinali; Rahbar, Mohammad; Minator Sajjadi, Mohammadreza; Jahansouz, Ali; Karimi Heris, Hossein

    2016-01-01

    Background Tibial plateau fractures can be successfully fixed utilizing 3.5 mm locking plates. However, there are some disadvantages to using these plates. Objectives In the current prospective study, we investigated the outcome of treating different types of tibial plateau fractures with 3.5 mm simple plates which, to our knowledge, has not been evaluated in previous studies. Materials and Methods Between 2011 and 2013, 32 patients aged 40 ± 0.2 years underwent open reduction and internal fixation for tibial plateau fractures with 3.5 mm simple plates. The patients were followed for 16.14 ± 2.1 months. At each patient’s final visit, the articular surface depression, medial proximal tibial angle, and slope angle were measured and compared with measurements taken early after the operation. The functional outcomes were measured with the WOMAC and Lysholm knee scores. Results The mean union time was 13 ± 1.2 weeks. The mean knee range of motion was 116.8° ± 3.3°. The mean WOMAC and Lysholm scores were 83.5 ± 1.8 and 76.8 ± 1.6, respectively. On the early postoperative and final X-rays, 87.5% and 84% of patients, respectively, had acceptable reduction. Medial proximal tibial and slope angles did not change significantly by the last visit. No patient was found to have complications related to the type of plate. Conclusions In this case series study, the fixation of different types of tibial plateau fractures with 3.5 mm simple non-locking and non-precontoured plates was associated with acceptable clinical, functional, and radiographic outcomes. Based on the advantages and costs of these plates, the authors recommend using 3.5 mm simple plates for different types of tibial plateau fractures. PMID:27626010

  6. Guide to Free-Loan Sports Films (16mm).

    ERIC Educational Resources Information Center

    1974

    This catalog provides information on free 16 mm films dealing with a wide variety of individual and team sports, such as football, golf, water sports, snow sports, racing, and baseball, as well as on general sports competition and safety. Unless otherwise noted, the films are in color and with sound. Titles are listed alphabetically under their…

  7. Propellant Residues Deposition from Firing of 40-mm Grenades

    DTIC Science & Technology

    2010-09-01

    the snow surface downrange of the firing positions in three sampling units on each pad. Samples were analyzed and results compo- sited to derive an...Processing and Analysis ..................................................................... 10 3.1 Snow samples...mm howitzers, propel- lant residues containing DNT were collected from the snow -covered area in front of one of the guns (Walsh, M.E. et al. 2004

  8. Downslope windstorm in Iceland - WRF/MM5 model comparison

    NASA Astrophysics Data System (ADS)

    Rögnvaldsson, Ó.; Bao, J.-W.; Ágústsson, H.; Ólafsson, H.

    2011-01-01

    A severe windstorm downstream of Mt. Öræfajökull in Southeast Iceland is simulated on a grid of 1 km horizontal resolution by using the PSU/NCAR MM5 model and the Advanced Research WRF model. Both models are run with a new, two equation planetary boundary layer (PBL) scheme as well as the ETA/MYJ PBL schemes. The storm is also simulated using six different micro-physics schemes in combination with the MYJ PBL scheme in WRF, as well as one "dry" run. Output from a 3 km MM5 domain simulation is used to initialise and drive both the 1 km MM5 and WRF simulations. Both models capture gravity-wave breaking over Mt. Öræfajökull, while the vertical structure of the lee wave differs between the two models and the PBL schemes. The WRF simulated downslope winds, using both the MYJ and 2EQ PBL schemes, are in good agreement with the strength of the observed downslope windstorm. The MM5 simulated surface winds, with the new two equation model, are in better agreement to observations than when using the ETA scheme. Micro-physics processes are shown to play an important role in the formation of downslope windstorms and a correctly simulated moisture distribution is decisive for a successful windstorm prediction. Of the micro-physics schemes tested, only the Thompson scheme captures the downslope windstorm.

  9. Advisory List of Instructional Media--16MM Films.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Educational Media.

    These two advisory lists include information on 16mm films appropriate for the K-12 instructional program. In both bibliographies films are listed in the following categories: communication skills; guidance; health, physical education, safety, and sports; science; and social studies. The list for the 1982-1983 school year also includes categories…

  10. Guide to Films (16 mm) About Ecology, Adaptation and Pollution.

    ERIC Educational Resources Information Center

    1971

    Synopses of 350 films (16 mm.) on ecology, adaptation of plants and animals to their environment, and environmental pollution are listed alphabetically by title in this guide. It specifies whether the film is black-and-white or color, its running time, and its source. An abbreviated subject index and a directory of sources are also provided. The…

  11. IMPLEMENTATION OF AN URBAN CANOPY PARAMETERIZATION IN MM5

    EPA Science Inventory

    The Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model (MM5) (Grell et al. 1994) has been modified to include an urban canopy parameterization (UCP) for fine-scale urban simulations (~1-km horizontal grid spacing). The UCP accounts for drag ...

  12. LIGA-fabricated compact mm-wave linear accelerator cavities.

    SciTech Connect

    Song, J.J.; Bajikar, S.S.; DeCarlo, F.; Kang, Y.W.; Kustom, R.L.; Mancini, D.C.; Nassiri, A.; Lai, B.; Feinerman, A.D.; White, V.

    1998-03-23

    Millimeter-wave rf cavities for use in linear accelerators, free-electron lasers, and mm-wave undulatory are under development at Argonne National Laboratory. Typical cavity dimensions are in the 1000 mm range, and the overall length of the accelerator structure, which consists of 30-100 cavities, is about 50-100 mm. An accuracy of 0.2% in the cavity dimensions is necessary in order to achieve a high Q-factor of the cavity. To achieve this these structures are being fabricated using deep X-ray lithography, electroforming, and assembly (LIGA). The first prototype cavity structures are designed for 108 GHz and 2p/3-mode operation. Input and output couplers are integrated with the cavity structures. The cavities are fabricated on copper substrates by electroforming copper into 1-mm-thick PMMA resists patterned by deep x-ray lithography and polishing the copper down to the desired thickness. These are fabricated separately and subsequently assembled with precision spacing and alignment using microspheres, optical fibers, or microfabricated spacers/alignment pieces. Details of the fabrication process, alignment, and assembly work are presented in here.

  13. Bell & Howell Introduces an 8mm Cartridge Concept

    ERIC Educational Resources Information Center

    Educ Screen Audiovisual Guide, 1970

    1970-01-01

    "Bell & Howell has developed a highly versatile cartidge projector system for cine and super 8mm formats. Because Bell & Howell believes that standardization is an important factor in the development of a cartridge system, it has built in a flexibility which will allow this standardization. (Author)

  14. Distinguishing between anomalous origin of the left coronary artery from the pulmonary trunk and dilated cardiomyopathy: role of echocardiographic measurement of the right coronary artery diameter.

    PubMed Central

    Koike, K; Musewe, N N; Smallhorn, J F; Freedom, R M

    1989-01-01

    Patients with anomalous origin of the left coronary artery from the pulmonary trunk usually have a large right coronary artery. This study examines the diagnostic value of measuring the diameter of the right coronary artery by echocardiography in distinguishing between this lesion and other causes of dilated cardiomyopathy. The diameter of the right coronary artery and the right coronary artery/aorta ratio were measured in the parasternal short axis view in 40 controls, 11 patients with dilated cardiomyopathy, and 10 with anomalous origin of the left coronary artery from the pulmonary trunk. In the controls, the diameter of the right coronary artery increased with age, but the right coronary artery/aorta ratio remained constant. In the control group the 95% upper limits of prediction for right coronary artery diameter were 1.6 mm for one month of age, 1.8 mm for three months, 2.0 mm for one year, 2.2 mm for two years, 2.4 mm for three years, 2.6 mm for four years, 2.7 mm for six years, 3.0 mm for eight years, and 3.2 mm for 10 years; and for right coronary/aorta ratios the limits were 0.17 for one month to one year, 0.18 for one to six years, 0.19 for six to 10 years, and 0.20 for more than 10 years. All patients with dilated cardiomyopathy had normal right coronary artery diameters and right coronary artery/aorta ratios (0.10-0.13). Those patients with anomalous origin of the left coronary artery from the pulmonary trunk had larger than normal right coronary artery diameter and a significant increase in the right coronary artery/aorta ratio (0.21-0.29). The presence of an anomalous left coronary artery was likely if the diameter of the right coronary artery or the right coronary artery/aorta ratio was larger than the normal 95% limits of prediction. Images Fig 1 PMID:2923759

  15. Studies on CDP-choline:1,2-diacylglycerol cholinephosphotransferase activity in rat arterial wall.

    PubMed

    Sasaki, N; Matsuoka, N; Shirai, K; Saito, Y; Kumagai, A

    1982-06-01

    The properties of CDP-choline:1,2-diacylglycerol cholinephosphotransferase (CPT) (EC 2.7.8.2.), which catalyzes de novo synthesis of phosphatidylcholine, were studied in rat arterial wall. The optimal pH of CPT of the arterial wall was about 8.5. On subcellular fractionation of the arterial wall, the highest activity was found in the microsome-rich fraction; the cytosolic fraction showed only a trace of activity. The Michaelis constant (KM) for CDP-choline was 0.019 mM. The CPT activity of a homogenate of arterial wall increased linearly with increase in concentration of diolein up to 3.2 mM. 20 mM magnesium and 0.2 mM manganese ions caused marked activation respectively and essential for the activity. Calcium, barium, cobalt, copper, and ferrous ions were inhibitory. 0.5 mM ethylenediaminetetraacetic acid (EDTA) and 0.5 mM glycoletherdiamine-N,N,N'N'-tetraacetic acid (GEDTA) increased the activity in the presence of 10 mM magnesium ion. Sonication of the enzyme solution and addition of high concentration of detergent, such as Triton X-100 and Tween 20, markedly decreased the activity. Porcine liver phosphatidylcholine, phosphatidylethanolamine, and especially polyenephosphatidylcholine increased CPT activity of the arterial wall, while lysophosphatidylcholine was strongly inhibitory. The properties of arterial CPT activity under various conditions are discussed.

  16. VLA 7-mm Observations of Massive Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Linz, Hendrik; Hofner, Peter; Araya, Esteban; Stecklum, Bringfried

    2003-07-01

    The early stages during the formation of massive stars are deeply enshrouded due to the presence of dense and dusty natal material. This prevents observations in the optical and often also in the near-infrared. The emission of the star-forming regions peaks in the far-infrared and sub-mm regime, but at these wavelengths, single-dish observations are restricted in spatial resolution and can give only upper limits on the energetics of the objects of interest. Interferometry at mm wavelengths is one appropriate technique to overcome these limitations. We have started an extensive programme to observe pre-selected massive star-forming regions. Our tool is the VLA and its 7-mm receiver system. The VLA can be operated in several antenna configurations delivering resolutions from 1.5 arcsec down to 0.05 arcsec, which is superior to other current mm-interferometers. Sub-arcsec resolution is strongly needed to disentangle the often crowded regions of high-mass star formation and to clearly separate our objects of interest from the adjacent ultracompact HII regions. At 7 mm we are on the save ground of the Rayleigh-Jeans limit even for emission of cold dust (a fact that is not always true for observations at smaller wavelengths). Almost all circumstellar density configurations are optically thin at 7 mm, thus, the observations will trace the total dust content. However, at 7 mm also the free-free emission from ionised gas (caused by the UV emission of the young massive stars) can contribute to the observed signal. Therefore, we have to identify and remove these "parasitic" constituents by extrapolating interferometric data obtained at cm-wavelengths. The targets are either taken from the list of Molinari (Molinari et al. 2000, A&A, 355, 617) or are well-known massive star-forming complexes, for which we have already acquired additional data at other wavelengths. We have started with observations at lower and medium resolution (1.5 - 0.5 arcsec) to distinguish candidates for

  17. Salt-dependent DNA superhelix diameter studied by small angle neutron scattering measurements and Monte Carlo simulations.

    PubMed Central

    Hammermann, M; Brun, N; Klenin, K V; May, R; Tóth, K; Langowski, J

    1998-01-01

    Using small angle neutron scattering we have measured the static form factor of two different superhelical DNAs, p1868 (1868 bp) and pUC18 (2686 bp), in dilute aqueous solution at salt concentrations between 0 and 1.5 M Na+ in 10 mM Tris at 0% and 100% D2O. For both DNA molecules, the theoretical static form factor was also calculated from an ensemble of Monte Carlo configurations generated by a previously described model. Simulated and measured form factors of both DNAs showed the same behavior between 10 and 100 mM salt concentration: An undulation in the scattering curve at a momentum transfer q = 0.5 nm-1 present at lower concentration disappears above 100 mM. The position of the undulation corresponds to a distance of approximately 10-20 nm. This indicated a change in the DNA superhelix diameter, as the undulation is not present in the scattering curve of the relaxed DNA. From the measured scattering curves of superhelical DNA we estimated the superhelix diameter as a function of Na+ concentration by a quantitative comparison with the scattering curve of relaxed DNA. The ratio of the scattering curves of superhelical and relaxed DNA is very similar to the form factor of a pair of point scatterers. We concluded that the distance of this pair corresponds to the interstrand separation in the superhelix. The computed superhelix diameter of 16.0 +/- 0.9 nm at 10 mM decreased to 9.0 +/- 0.7 nm at 100 mM salt concentration. Measured and simulated scattering curves agreed almost quantitatively, therefore we also calculated the superhelix diameter from the simulated conformations. It decreased from 18.0 +/- 1.5 nm at 10 mM to 9.4 +/- 1.5 nm at 100 mM salt concentration. This value did not significantly change to lower values at higher Na+ concentration, in agreement with results obtained by electron microscopy, scanning force microscopy imaging in aqueous solution, and recent MC simulations, but in contrast to the observation of a lateral collapse of the DNA superhelix

  18. Sb-based IR photodetector epiwafers on 100 mm GaSb substrates manufactured by MBE

    NASA Astrophysics Data System (ADS)

    Fastenau, Joel M.; Lubyshev, Dmitri; Qiu, Yueming; Liu, Amy W. K.; Koerperick, Edwin J.; Olesberg, Jon T.; Norton, Dennis

    2013-07-01

    Antimony-based materials continue to provide great interest for infrared photodetector and focal plane array imaging applications. Detector architectures include InAs/Ga(In)Sb strained-layer superlattices, which create a type-II band alignment that can be tailored to cover a wide range of the mid- and long-wavelength bands by varying the thickness and composition of the constituent materials, and bulk InAsSb-based XBn barrier designs. These materials can provide desirable detector features such as wider wavelength range, suppression of tunneling currents, improved quantum efficiency, and higher operating temperatures. In order to bring these advantages to market, a reliable manufacturing process must be established on large diameter substrates. We report our latest work on the molecular beam epitaxy growth of Sb-detector epiwafers on 100 mm diameter GaSb substrates in a multi-wafer production format. The growth process has been established to address the challenges of these demanding structures, including the large numbers of alternating thin layers and mixed group-V elements. Various characterization techniques demonstrate excellent surface morphology, crystalline structure quality, and optical properties of the epiwafers. The measured wafer-to-wafer consistency and cross-wafer uniformity demonstrate the potential for volume manufacturing.

  19. Experimental characterization of mm-wave detection by a micro-array of Golay cells

    NASA Astrophysics Data System (ADS)

    Denison, Douglas R.; Knotts, Michael E.; McConney, Michael E.; Tsukruk, Vladimir V.

    2009-05-01

    We present experimental results for an uncooled imaging focal plane array technology that consists of a polymer/metal/polymer layered membrane suspended over a micro-fabricated array of cavities. The device operation is Golay-like (heating of air in the cavity causes a detectable deflection of the membrane proportional to incident EM power), but potentially offers both greater sensitivity and more read-out options (optical or electrical) than a traditional Golay cell through tailoring of the membrane properties. The membrane is formed from a layer-by-layer deposition of polymer with one or more monolayers of gold nanoparticles (or other metal) that help control the membrane's elasticity and deformation-dependent optical reflectivity/electrical conductivity. Baseline capabilities of the device have been established through optical measurements of membrane deflection due to incident mm-wave radiation modulated at 30 Hz (corresponding to a video refresh rate). The device demonstrates an NEP of 300 nW/√Hz at 105 GHz for a 19-layer membrane (9 poly/1 Au/9 poly) suspended over an array of 80 μm diameter cavities (depth = 100 μm) etched in a 500 μm thick substrate of Si. Calculations of membrane sensitivity show that this NEP could be reduced to ~ 100 pW/√Hz with enlarged cavity diameters on the order of 600 μm.

  20. Electrical Stimulation of Mammalian Retinal Ganglion Cells Using Dense Arrays of Small-Diameter Electrodes

    NASA Astrophysics Data System (ADS)

    Sekirnjak, Chris; Hottowy, Pawel; Sher, Alexander; Dabrowski, Wladyslaw; Litke, Alan M.; Chichilnisky, E. J.

    Current epiretinal implants contain a small number of electrodes with diameters of a few hundred microns. Smaller electrodes are desirable to increase the spatial resolution of artificial sight. To lay the foundation for the next generation of retinal prostheses, we assessed the stimulation efficacy of micro-fabricated arrays of 61 platinum disk electrodes with diameters 8-12 μm, spaced 60 μm apart. Isolated pieces of rat, guinea pig, and monkey retina were placed on the multi-electrode array ganglion cell side down and stimulated through individual electrodes with biphasic, charge-balanced current pulses. Spike responses from retinal ganglion cells were recorded either from the same or a neighboring electrode. Most pulses evoked only 1-2 spikes with short latencies (0.3-10 ms), and rarely was more than one recorded ganglion cell stimulated. Threshold charge densities for eliciting spikes in ganglion cells were typically below 0.15 mC/cm2 for pulse durations between 50 and 200 μs, corresponding to charge thresholds of ˜ 100 pC. Stimulation remained effective after several hours and at frequencies up to 100 Hz. Application of cadmium chloride did not abolish evoked spikes, implying direct activation. Thus, electrical stimulation of mammalian retina with small-diameter electrodes is achievable, providing high temporal and spatial precision with low charge densities.