Pilot randomized trial of a volitional help sheet-based tool to increase leisure time physical activity in breast cancer survivors.

PubMed

Chapman, Janine; Fletcher, Chloe; Flight, Ingrid; Wilson, Carlene

2018-05-16

To develop and test a volitional help sheet-based tool to improve physical activity in breast cancer survivors compared to a standard self-generated implementation intention intervention. Pilot randomized trial conducted online over 3 months. Participants were randomized to an online volitional help sheet (n = 50) or implementation intention (n = 51) intervention. Measures were taken at baseline, 1 and 3 months. The main outcome measure was moderate-strenuous leisure time physical activity. Secondary outcomes were health-related quality of life and mood. Participants exposed to the volitional help sheet and implementation intention interventions showed similar effects after 1 month, with both groups reporting a significant increase in moderate-strenuous physical activity. After 3 months, the initial increase in physical activity was maintained by the volitional help sheet group, but not the implementation intention group. Improvements were also found for negative affect and emotional quality of life. While both interventions show promise in promoting physical activity in breast cancer survivors, the volitional help sheet may be more effective for facilitating lasting change and emotional well-being. Findings suggest that the volitional help sheet may have potential to offer a cost-effective contribution to consumer-led tertiary preventive health. Future research should test these initial findings in a definitive trial. Statement of contribution What is already known on this subject? Physical activity is important for optimizing health in breast cancer survivors. Despite this, physical activity in this cohort remains low. Theory-based strategies are needed to help breast cancer survivors independently manage and maintain regular physical activity over the long term. What does this study add? Online planning interventions can improve physical activity in breast cancer survivors. Volitional help sheets, but not implementation intentions, show sustained effects for 3 months. The intervention shows promise as a potential low-cost addition to long-term survivorship care plans. © 2018 The British Psychological Society.

Active microchannel fluid processing unit and method of making

DOEpatents

Bennett, Wendy D [Kennewick, WA; Martin, Peter M [Kennewick, WA; Matson, Dean W [Kennewick, WA; Roberts, Gary L [West Richland, WA; Stewart, Donald C [Richland, WA; Tonkovich, Annalee Y [Pasco, WA; Zilka, Jennifer L [Pasco, WA; Schmitt, Stephen C [Dublin, OH; Werner, Timothy M [Columbus, OH

2001-01-01

The present invention is an active microchannel fluid processing unit and method of making, both relying on having (a) at least one inner thin sheet; (b) at least one outer thin sheet; (c) defining at least one first sub-assembly for performing at least one first unit operation by stacking a first of the at least one inner thin sheet in alternating contact with a first of the at least one outer thin sheet into a first stack and placing an end block on the at least one inner thin sheet, the at least one first sub-assembly having at least a first inlet and a first outlet; and (d) defining at least one second sub-assembly for performing at least one second unit operation either as a second flow path within the first stack or by stacking a second of the at least one inner thin sheet in alternating contact with second of the at least one outer thin sheet as a second stack, the at least one second sub-assembly having at least a second inlet and a second outlet.

Active microchannel fluid processing unit and method of making

DOEpatents

Bennett, Wendy D [Kennewick, WA; Martin, Peter M [Kennewick, WA; Matson, Dean W [Kennewick, WA; Roberts, Gary L [West Richland, WA; Stewart, Donald C [Richland, WA; Tonkovich, Annalee Y [Pasco, WA; Zilka, Jennifer L [Pasco, WA; Schmitt, Stephen C [Dublin, OH; Werner, Timothy M [Columbus, OH

2002-12-10

The present invention is an active microchannel fluid processing unit and method of making, both relying on having (a) at least one inner thin sheet; (b) at least one outer thin sheet; (c) defining at least one first sub-assembly for performing at least one first unit operation by stacking a first of the at least one inner thin sheet in alternating contact with a first of the at least one outer thin sheet into a first stack and placing an end block on the at least one inner thin sheet, the at least one first sub-assembly having at least a first inlet and a first outlet; and (d) defining at least one second sub-assembly for performing at least one second unit operation either as a second flow path within the first stack or by stacking a second of the at least one inner thin sheet in alternating contact with second of the at least one outer thin sheet as a second stack, the at least one second sub-assembly having at least a second inlet and a second outlet.

Distribution of Region 1 and 2 currents in the quietand substorm time plasma sheetfrom THEMIS observations

NASA Astrophysics Data System (ADS)

Liu, J.; Angelopoulos, V.; Chu, X.; McPherron, R. L.

2016-12-01

Although Earth's Region 1 and 2 currents are related to activities such as substorm initiation, their magnetospheric origin remains unclear. Utilizing the triangular configuration of THEMIS probes at 8-12 RE downtail, we seek the origin of nightside Region 1 and 2 currents. The triangular configuration allows a curlometer-like technique which do not rely on active-time boundary crossings, so we can examine the current distribution in quiet times as well as active times. Our statistical study reveals that both Region 1 and 2 currents exist in the plasma sheet during quiet and active times. Especially, this is the first unequivocal, in-situ evidence of the existence of Region 2 currents in the plasma sheet. Farther away from the neutral sheet than the Region 2 currents lie the Region 1 currents which extend at least to the plasma sheet boundary layer. At geomagnetic quiet times, the separation between the two currents is located 2.5 RE from the neutral sheet. These findings suggest that the plasma sheet is a source of Region 1 and 2 currents regardless of geomagnetic activity level. During substorms, the separation between Region 1 and 2 currents migrates toward (away from) the neutral sheet as the plasma sheet thins (thickens). This migration indicates that the deformation of Region 1 and 2 currents is associated with redistribution of FAC sources in the magnetotail. In some substorms when the THEMIS probes encounter a dipolarization, a substorm current wedge (SCW) can be inferred from our technique, and it shows a distinctively larger current density than the pre-existing Region 1 currents. This difference suggests that the SCW is not just an enhancement of the pre-existing Region 1 current; the SCW and the Region 1 currents have different sources.

Effect of Cell Sheet Manipulation Techniques on the Expression of Collagen Type II and Stress Fiber Formation in Human Chondrocyte Sheets.

PubMed

Wongin, Sopita; Waikakul, Saranatra; Chotiyarnwong, Pojchong; Siriwatwechakul, Wanwipa; Viravaidya-Pasuwat, Kwanchanok

2018-03-01

Cell sheet technology is applied to human articular chondrocytes to construct a tissue-like structure as an alternative treatment for cartilage defect. The effect of a gelatin manipulator, as a cell sheet transfer system, on the quality of the chondrocyte sheets was investigated. The changes of important chondrogenic markers and stress fibers, resulting from the cell sheet manipulation, were also studied. The chondrocyte cell sheets were constructed with patient-derived chondrocytes using a temperature-responsive polymer and a gelatin manipulator as a transfer carrier. The properties of the cell sheets, including sizes, expression levels of collagen type II and I, and the localization of the stress fibers, were assessed and compared with those of the cell sheets harvested without the gelatin manipulator. Using the gelatin manipulator, the original size of the chondrocyte cell sheets was retained with abundant stress fibers, but with a decrease in the expression of collagen type II. Without the gelatin manipulator, although the cell shrinkage occurred, the cell sheet with suppressed stress fiber formation showed significantly higher levels of collagen type II. These results support our observations that stress fiber formation in chondrocyte cell sheets affected the production of chondrogenic markers. These densely packed tissue-like structures possessed a good chondrogenic activity, indicating their potential for use in autologous chondrocyte implantation to treat cartilage defects.

Field evaluation of ZeroFly--an insecticide incorporated plastic sheeting against malaria vectors & its impact on malaria transmission in tribal area of northern Orissa.

PubMed

Sharma, S K; Upadhyay, A K; Haque, M A; Tyagi, P K; Mohanty, S S; Mittal, P K; Dash, A P

2009-10-01

Insecticide incorporated plastic sheeting is a new technology to control mosquitoes in emergency shelter places and also temporary habitations in different locations. Therefore, field studies were conducted to assess the efficacy of ZeroFly plastic sheeting treated with deltamethrin on prevailing disease vectors Anopheles culicifacies and An. fluviatilis and its impact on malaria transmission in one of the highly endemic areas of Orissa. The study was conducted in Birkera block of Sundargarh district, Orissa state. The study area comprised 3 villages, which were randomized as ZeroFly plastic sheet, untreated plastic sheet and no sheet area. ZeroFly plastic sheets and untreated plastic sheets were fixed in study and control villages respectively covering all the rooms in each household. Longitudinal studies were conducted on the bioefficacy with the help of cone bioassays, monitoring of the mosquito density through hand catch, floor sheet and exit trap collections and fortnightly domiciliary active surveillance in all the study villages. In ZeroFly plastic sheeting area, there was a significant reduction of 84.7 per cent in the entry rate of total mosquitoes in comparison to pre-intervention phase. There was 56.2 per cent immediate mortality in total mosquitoes in houses with ZeroFly sheeting. The overall feeding success rate of mosquitoes in the trial village was only 12.5 per cent in comparison to 49.7 and 51.1 per cent in villages with untreated plastic sheet and no sheet respectively. There was a significant reduction of 65.0 and 70.5 per cent in malaria incidence in ZeroFly plastic sheeting area as compared to untreated plastic sheet and no sheet area respectively. Our study showed that introduction of ZeroFly plastic sheets in a community-based intervention programme is operationally feasible to contain malaria especially in the high transmission difficult areas.

ISMIP6 - initMIP: Greenland ice sheet model initialisation experiments

NASA Astrophysics Data System (ADS)

Goelzer, Heiko; Nowicki, Sophie; Payne, Tony; Larour, Eric; Abe Ouchi, Ayako; Gregory, Jonathan; Lipscomb, William; Seroussi, Helene; Shepherd, Andrew; Edwards, Tamsin

2016-04-01

Earlier large-scale Greenland ice sheet sea-level projections e.g. those run during ice2sea and SeaRISE initiatives have shown that ice sheet initialisation can have a large effect on the projections and gives rise to important uncertainties. This intercomparison exercise (initMIP) aims at comparing, evaluating and improving the initialization techniques used in the ice sheet modeling community and to estimate the associated uncertainties. It is the first in a series of ice sheet model intercomparison activities within ISMIP6 (Ice Sheet Model Intercomparison Project for CMIP6). The experiments are conceived for the large-scale Greenland ice sheet and are designed to allow intercomparison between participating models of 1) the initial present-day state of the ice sheet and 2) the response in two schematic forward experiments. The latter experiments serve to evaluate the initialisation in terms of model drift (forward run without any forcing) and response to a large perturbation (prescribed surface mass balance anomaly). We present and discuss first results of the intercomparison and highlight important uncertainties with respect to projections of the Greenland ice sheet sea-level contribution.

Basic Facialist. Teacher Edition. Cosmetology Series.

ERIC Educational Resources Information Center

Rogers, Jeanette A.

This Oklahoma curriculum guide contains six units. Each instructional unit includes some or all of these basic components: performance objectives; suggested activities for the teacher; pretest; handouts; information sheets; transparency masters; assignment sheets; job sheets; practical tests; written tests; and answers to pretest, assignment…

Particulate photocatalyst sheets for Z-scheme water splitting: advantages over powder suspension and photoelectrochemical systems and future challenges.

PubMed

Wang, Qian; Hisatomi, Takashi; Katayama, Masao; Takata, Tsuyoshi; Minegishi, Tsutomu; Kudo, Akihiko; Yamada, Taro; Domen, Kazunari

2017-04-28

Water splitting using semiconductor photocatalysts has been attracting growing interest as a means of solar energy based conversion of water to hydrogen, a clean and renewable fuel. Z-scheme photocatalytic water splitting based on the two-step excitation of an oxygen evolution photocatalyst (OEP) and a hydrogen evolution photocatalyst (HEP) is a promising approach toward the utilisation of visible light. In particular, a photocatalyst sheet system consisting of HEP and OEP particles embedded in a conductive layer has been recently proposed as a new means of obtaining efficient and scalable redox mediator-free Z-scheme solar water splitting. In this paper, we discuss the advantages and disadvantages of the photocatalyst sheet approach compared to conventional photocatalyst powder suspension and photoelectrochemical systems through an examination of the water splitting activity of Z-scheme systems based on SrTiO 3 :La,Rh as the HEP and BiVO 4 :Mo as the OEP. This photocatalyst sheet was found to split pure water much more efficiently than the powder suspension and photoelectrochemical systems, because the underlying metal layer efficiently transfers electrons from the OEP to the HEP. The photocatalyst sheet also outperformed a photoelectrochemical parallel cell during pure water splitting. The effects of H + /OH - concentration overpotentials and of the IR drop are reduced in the case of the photocatalyst sheet compared to photoelectrochemical systems, because the HEP and OEP are situated in close proximity to one another. Therefore, the photocatalyst sheet design is well-suited to efficient large-scale applications. Nevertheless, it is also noted that the photocatalytic activity of these sheets drops markedly with increasing background pressure because of reverse reactions involving molecular oxygen under illumination as well as delays in gas bubble desorption. It is shown that appropriate surface modifications allow the photocatalyst sheet to maintain its water splitting activity at elevated pressure. Accordingly, we conclude that the photocatalyst sheet system is a viable option for the realisation of efficient solar fuel production.

Drafting. Competency Based Curriculum.

ERIC Educational Resources Information Center

Everly, Al; And Others

This competency based drafting curriculum is presented in seven specialization sections with units in each section containing a competency statement, performance objective, learning activities, evaluation, and quiz or problem sheets. Some units also contain answer sheets and/or handout sheets. Sections and number of units presented are (1) basic…

Aligned carbon nanotube-silicon sheets: a novel nano-architecture for flexible lithium ion battery electrodes.

PubMed

Fu, Kun; Yildiz, Ozkan; Bhanushali, Hardik; Wang, Yongxin; Stano, Kelly; Xue, Leigang; Zhang, Xiangwu; Bradford, Philip D

2013-09-25

Aligned carbon nanotube sheets provide an engineered scaffold for the deposition of a silicon active material for lithium ion battery anodes. The sheets are low-density, allowing uniform deposition of silicon thin films while the alignment allows unconstrained volumetric expansion of the silicon, facilitating stable cycling performance. The flat sheet morphology is desirable for battery construction. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Unitary plate electrode

NASA Technical Reports Server (NTRS)

Rowlette, John J. (Inventor); Clough, Thomas J. (Inventor); Josefowicz, Jack Y. (Inventor); Sibert, John W. (Inventor)

1985-01-01

The unitary electrode (10) comprises a porous sheet (12) of fiberglass the strands (14) of which contain a coating (16) of conductive tin oxide. The lower portion of the sheet contains a layer (18) of resin and the upper layer (20) contains lead dioxide forming a positive active electrode on an electrolyte-impervious layer. The strands (14) form a continuous conduction path through both layers (16, 18). Tin oxide is prevented from reduction by coating the surface of the plate facing the negative electrode with a conductive, impervious layer resistant to reduction such as a thin film (130) of lead or graphite filled resin adhered to the plate with a layer (31) of conductive adhesive. The plate (10) can be formed by casting a molten resin from kettle (60) onto a sheet of glass wool (56) overlying a sheet of lead foil and then applying positive active paste from hopper (64) into the upper layer (68). The plate can also be formed by passing an assembly of a sheet ( 80) of resin, a sheet (86) of sintered glass and a sheet (90) of lead between the nip (92) of heated rollers (93, 95) and then filling lead oxide into the pores (116) of the upper layer (118).

Comprehensive Small Engine Repair.

ERIC Educational Resources Information Center

Hires, Bill; And Others

This curriculum guide contains the basic information needed to repair all two- and four-stroke cycle engines. The curriculum covers four areas, each consisting of one or more units of instruction that include performance objectives, suggested activities for teacher and students, information sheets, assignment sheets, job sheets, visual aids,…

Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

PubMed Central

Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

2017-01-01

TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties. PMID:28067318

Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

NASA Astrophysics Data System (ADS)

Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

2017-01-01

TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties.

Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel.

PubMed

Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

2017-01-09

TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties.

Mechanical Drafting with CAD. Teacher Edition.

ERIC Educational Resources Information Center

McClain, Gerald R.

This instructor's manual contains 13 units of instruction for a course on mechanical drafting with options for using computer-aided drafting (CAD). Each unit includes some or all of the following basic components of a unit of instruction: objective sheet, suggested activities for the teacher, assignment sheets and answers to assignment sheets,…

World Population: Facts in Focus. World Population Data Sheet Workbook. Population Learning Series.

ERIC Educational Resources Information Center

Crews, Kimberly A.

This workbook teaches population analysis using world population statistics. To complete the four student activity sheets, the students refer to the included "1988 World Population Data Sheet" which lists nations' statistical data that includes population totals, projected population, birth and death rates, fertility levels, and the…

75 FR 55579 - Proposed Agency Information Collection Activities; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-13

... balance sheet data on major categories of consumer and business credit receivables and on major short-term... items are collected to provide a full balance sheet. A supplemental section collects data on securitized... two columns to create a clearer distinction among broad balance sheet data items, which are collected...

Results of the Greenland Ice Sheet Model Initialisation Experiments ISMIP6 - initMIP-Greenland

NASA Astrophysics Data System (ADS)

Goelzer, H.; Nowicki, S.; Edwards, T.; Beckley, M.; Abe-Ouchi, A.; Aschwanden, A.; Calov, R.; Gagliardini, O.; Gillet-chaulet, F.; Golledge, N. R.; Gregory, J. M.; Greve, R.; Humbert, A.; Huybrechts, P.; Larour, E. Y.; Lipscomb, W. H.; Le ´h, S.; Lee, V.; Kennedy, J. H.; Pattyn, F.; Payne, A. J.; Rodehacke, C. B.; Rückamp, M.; Saito, F.; Schlegel, N.; Seroussi, H. L.; Shepherd, A.; Sun, S.; Vandewal, R.; Ziemen, F. A.

2016-12-01

Earlier large-scale Greenland ice sheet sea-level projections e.g. those run during ice2sea and SeaRISE initiatives have shown that ice sheet initialisation can have a large effect on the projections and gives rise to important uncertainties. The goal of this intercomparison exercise (initMIP-Greenland) is to compare, evaluate and improve the initialization techniques used in the ice sheet modeling community and to estimate the associated uncertainties. It is the first in a series of ice sheet model intercomparison activities within ISMIP6 (Ice Sheet Model Intercomparison Project for CMIP6). Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of 1) the initial present-day state of the ice sheet and 2) the response in two schematic forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without any forcing) and response to a large perturbation (prescribed surface mass balance anomaly). We present and discuss final results of the intercomparison and highlight important uncertainties with respect to projections of the Greenland ice sheet sea-level contribution.

Rapid fabricating technique for multi-layered human hepatic cell sheets by forceful contraction of the fibroblast monolayer.

PubMed

Sakai, Yusuke; Koike, Makiko; Hasegawa, Hideko; Yamanouchi, Kosho; Soyama, Akihiko; Takatsuki, Mitsuhisa; Kuroki, Tamotsu; Ohashi, Kazuo; Okano, Teruo; Eguchi, Susumu

2013-01-01

Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions.

Magnetic configurations of the tilted current sheets in magnetotail

NASA Astrophysics Data System (ADS)

Shen, C.; Rong, Z. J.; Li, X.; Dunlop, M.; Liu, Z. X.; Malova, H. V.; Lucek, E.; Carr, C.

2008-11-01

In this research, the geometrical structures of tilted current sheet and tail flapping waves have been analysed based on multiple spacecraft measurements and some features of the tilted current sheets have been made clear for the first time. The geometrical features of the tilted current sheet revealed in this investigation are as follows: (1) The magnetic field lines (MFLs) in the tilted current sheet are generally plane curves and the osculating planes in which the MFLs lie are about vertical to the equatorial plane, while the normal of the tilted current sheet leans severely to the dawn or dusk side. (2) The tilted current sheet may become very thin, the half thickness of its neutral sheet is generally much less than the minimum radius of the curvature of the MFLs. (3) In the neutral sheet, the field-aligned current density becomes very large and has a maximum value at the center of the current sheet. (4) In some cases, the current density is a bifurcated one, and the two humps of the current density often superpose two peaks in the gradient of magnetic strength, indicating that the magnetic gradient drift current is possibly responsible for the formation of the two humps of the current density in some tilted current sheets. Tilted current sheets often appear along with tail current sheet flapping waves. It is found that, in the tail flapping current sheets, the minimum curvature radius of the MFLs in the current sheet is rather large with values around 1 RE, while the neutral sheet may be very thin, with its half thickness being several tenths of RE. During the flapping waves, the current sheet is tilted substantially, and the maximum tilt angle is generally larger than 45°. The phase velocities of these flapping waves are several tens km/s, while their periods and wavelengths are several tens of minutes, and several earth radii, respectively. These tail flapping events generally last several hours and occur during quiet periods or periods of weak magnetospheric activity.

Synthesis of porous sheet-like Co{sub 3}O{sub 4} microstructure by precipitation method and its potential applications in the thermal decomposition of ammonium perchlorate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu Shanshan; Jing Xiaoyan; Liu Jingyuan

2013-01-15

Porous sheet-like cobalt oxide (Co{sub 3}O{sub 4}) were successfully synthesized by precipitation method combined with calcination of cobalt hydroxide precursors. The structure, morphology and porosity properties of the products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption measurement. The as-prepared sheet-like microstructures were approximately 2-3 {mu}m in average diameter, and the morphology of the cobalt hydroxide precursors was retained after the calcination process. However, it appeared a large number of uniform pores in the sheets after calcination. In order to calculate the potential catalytic activity, the thermal decomposition of ammoniummore » perchlorate (AP) has been analyzed, in which cobalt oxide played a role of an additive and the porous sheet-like Co{sub 3}O{sub 4} microstructures exhibited high catalytic performance and considerable decrease in the thermal decomposition temperature of AP. Moreover, a formation mechanism for the sheet-like microstructures has been discussed. - Graphical abstract: Porous sheet-like Co{sub 3}O{sub 4} were synthesized by facile precipitation method combined with calcination of {beta}-Co(OH){sub 2} precursors. Thermogravimetric-differential scanning calorimetric analysis indicates potential catalytic activity in the thermal decomposition of ammonium perchlorate. Highlights: Black-Right-Pointing-Pointer Synthesis of sheet-like {beta}-Co(OH){sub 2} precursors by precipitation method. Black-Right-Pointing-Pointer Porous sheet-like Co{sub 3}O{sub 4} were obtained by calcining {beta}-Co(OH){sub 2} precursors. Black-Right-Pointing-Pointer The possible formation mechanism of porous sheet-like Co{sub 3}O{sub 4} has been discussed. Black-Right-Pointing-Pointer Porous sheet-like Co{sub 3}O{sub 4} decrease the thermal decomposition temperature of ammonium perchlorate.« less

Using the glacial geomorphology of palaeo-ice streams to understand mechanisms of ice sheet collapse

NASA Astrophysics Data System (ADS)

Stokes, Chris R.; Margold, Martin; Clark, Chris; Tarasov, Lev

2017-04-01

Processes which bring about ice sheet deglaciation are critical to our understanding of glacial-interglacial cycles and ice sheet sensitivity to climate change. The precise mechanisms of deglaciation are also relevant to our understanding of modern-day ice sheet stability and concerns over global sea level rise. Mass loss from ice sheets can be broadly partitioned between melting and a 'dynamic' component whereby rapidly-flowing ice streams/outlet glaciers transfer ice from the interior to the oceans. Surface and basal melting (e.g. of ice shelves) are closely linked to atmospheric and oceanic conditions, but the mechanisms that drive dynamic changes in ice stream discharge are more complex, which generates much larger uncertainties about their future contribution to ice sheet mass loss and sea level rise. A major problem is that observations of modern-day ice streams typically span just a few decades and, at the ice-sheet scale, it is unclear how the entire drainage network of ice streams evolves during deglaciation. A key question is whether ice streams might increase and sustain rates of mass loss over centuries or millennia, beyond those expected for a given ocean-climate forcing. To address this issue, numerous workers have sought to understand ice stream dynamics over longer time-scales using their glacial geomorphology in the palaeo-record. Indeed, our understanding of their geomorphology has grown rapidly in the last three decades, from almost complete ignorance to a detailed knowledge of their geomorphological products. Building on this body of work, this paper uses the glacial geomorphology of 117 ice streams in the North American Laurentide Ice Sheet to reconstruct their activity during its deglaciation ( 22,000 to 7,000 years ago). Ice stream activity was characterised by high variability in both time and space, with ice streams switching on and off in different locations. During deglaciation, we find that their overall number decreased, they occupied a progressively smaller percentage of the ice sheet perimeter, and their total discharge decreased. Underlying geology and topography clearly influenced ice stream activity, but - at the ice sheet scale - their drainage network adjusted and was strongly linked to changes in ice sheet volume. It is unclear whether these findings are directly translatable to modern ice sheets but, contrary to the view that sees ice streams as unstable entities that can draw-down large sectors of an ice sheet and accelerate its demise, we conclude that they reduced in effectiveness during deglaciation of the Laurentide Ice Sheet, with final deglaciation accomplished most effectively by surface melting. This raises some interesting questions about the source and nature of major meltwater pulses and iceberg discharge events in the sea-level record.

Preparation of Caco-2 cell sheets using plasma polymerised acrylic acid as a weak boundary layer.

PubMed

Majani, Ruby; Zelzer, Mischa; Gadegaard, Nikolaj; Rose, Felicity R; Alexander, Morgan R

2010-09-01

The use of cell sheets for tissue engineering applications has considerable advantages over single cell seeding techniques. So far, only thermoresponsive surfaces have been used to manufacture cell sheets without chemically disrupting the cell-surface interactions. Here, we present a new and facile technique to prepare sheets of epithelial cells using plasma polymerised acrylic acid films. The cell sheets are harvested by gentle agitation of the media without the need of any additional external stimulus. We demonstrate that the plasma polymer deposition conditions affect the viability and metabolic activity of the cells in the sheet and relate these effects to the different surface properties of the plasma polymerised acrylic acid films. Based on surface analysis data, a first attempt is made to explain the mechanism behind the cell sheet formation. The advantage of the epithelial cell sheets generated here over single cell suspensions to seed a PLGA scaffold is presented. The scaffold itself, prepared using a mould fabricated via photolithography, exhibits a unique architecture that mimics closely the dimensions of the native tissue (mouse intestine). Copyright 2010 Elsevier Ltd. All rights reserved.

Results of the Greenland ice sheet model initialisation experiments: ISMIP6 - initMIP-Greenland

NASA Astrophysics Data System (ADS)

Goelzer, Heiko; Nowicki, Sophie; Edwards, Tamsin; Beckley, Matthew

2017-04-01

Ice sheet model initialisation has a large effect on projected future sea-level contributions and gives rise to important uncertainties. The goal of this intercomparison exercise for the continental-scale Greenland ice sheet is therefore to compare, evaluate and improve the initialisation techniques used in the ice sheet modelling community. The initMIP-Greenland project is the first in a series of ice sheet model intercomparison activities within ISMIP6 (Ice Sheet Model Intercomparison Project for CMIP6). The experimental set-up has been designed to allow comparison of the initial present-day state of the Greenland ice sheet between participating models and against observations. Furthermore, the initial states are tested with two schematic forward experiments to evaluate the initialisation in terms of model drift (forward run without any forcing) and response to a large perturbation (prescribed surface mass balance anomaly). We present and discuss results that highlight the wide diversity of data sets, boundary conditions and initialisation techniques used in the community to generate initial states of the Greenland ice sheet.

Dylan Pritchett, Storyteller. Cue Sheet for Students.

ERIC Educational Resources Information Center

Evans, Karen L. B.

Designed to be used before and after attending a storytelling performance by Dylan Pritchett, this cue sheet presents information about the performance and suggests activities that can be done with classmates, friends, or family members. The cue sheet discusses where and why people tell stories, what makes a story good for telling, what makes a…

Technology Systems. Laboratory Activities.

ERIC Educational Resources Information Center

Brame, Ray; And Others

This guide contains 43 modules of laboratory activities for technology education courses. Each module includes an instructor's resource sheet and the student laboratory activity. Instructor's resource sheets include some or all of the following elements: module number, course title, activity topic, estimated time, essential elements, objectives,…

Principles for designing proteins with cavities formed by curved β sheets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcos, Enrique; Basanta, Benjamin; Chidyausiku, Tamuka M.

Active sites and ligand-binding cavities in native proteins are often formed by curved β sheets, and the ability to control β-sheet curvature would allow design of binding proteins with cavities customized to specific ligands. Toward this end, we investigated the mechanisms controlling β-sheet curvature by studying the geometry of β sheets in naturally occurring protein structures and folding simulations. The principles emerging from this analysis were used to design, de novo, a series of proteins with curved β sheets topped with α helices. Nuclear magnetic resonance and crystal structures of the designs closely match the computational models, showing that β-sheetmore » curvature can be controlled with atomic-level accuracy. Our approach enables the design of proteins with cavities and provides a route to custom design ligand-binding and catalytic sites.« less

Ice sheets play important role in climate change

NASA Astrophysics Data System (ADS)

Clark, Peter U.; MacAyeal, Douglas R.; Andrews, John T.; Bartlein, Patrick J.

Ice sheets once were viewed as passive elements in the climate system enslaved to orbitally generated variations in solar radiation. Today, modeling results and new geologic records suggest that ice sheets actively participated in late-Pleistocene climate change, amplifying or driving significant variability at millennial as well as orbital timescales. Although large changes in global ice volume were ultimately caused by orbital variations (the Milankovitch hypothesis), once in existence, the former ice sheets behaved dynamically and strongly influenced regional and perhaps even global climate by altering atmospheric and oceanic circulation and temperature.Experiments with General Circulation Models (GCMs) yielded the first inklings of ice sheets' climatic significance. Manabe and Broccoli [1985], for example, found that the topographic and albedo effects of ice sheets alone explain much of the Northern Hemisphere cooling identified in paleoclimatic records of the last glacial maximum (˜21 ka).

Function of Platelet-Induced Epithelial Attachment at Titanium Surfaces Inhibits Microbial Colonization.

PubMed

Maeno, M; Lee, C; Kim, D M; Da Silva, J; Nagai, S; Sugawara, S; Nara, Y; Kihara, H; Nagai, M

2017-06-01

The aim of this study was to evaluate the barrier function of platelet-induced epithelial sheets on titanium surfaces. The lack of functional peri-implant epithelial sealing with basal lamina (BL) attachment at the interface of the implant and the adjacent epithelium allows for bacterial invasion, which may lead to peri-implantitis. Although various approaches have been reported to combat bacterial infection by surface modifications to titanium, none of these have been successful in a clinical application. In our previous study, surface modification with protease-activated receptor 4-activating peptide (PAR4-AP), which induced platelet activation and aggregation, was successful in demonstrating epithelial attachment via BL and epithelial sheet formation on the titanium surface. We hypothesized that the platelet-induced epithelial sheet on PAR4-AP-modified titanium surfaces would reduce bacterial attachment, penetration, and invasion. Titanium surface was modified with PAR4-AP and incubated with platelet-rich plasma (PRP). The aggregated platelets released collagen IV, a critical BL component, onto the PAR4-AP-modified titanium surface. Then, human gingival epithelial cells were seeded on the modified titanium surface and formed epithelial sheets. Green fluorescent protein (GFP)-expressing Escherichia coli was cultured onto PAR4-AP-modified titanium with and without epithelial sheet formation. While Escherichia coli accumulated densely onto the PAR4-AP titanium lacking epithelial sheet, few Escherichia coli were observed on the epithelial sheet on the PAR4-AP surface. No bacterial invasion into the interface of the epithelial sheet and the titanium surface was observed. These in vitro results indicate the efficacy of a platelet-induced epithelial barrier that functions to prevent bacterial attachment, penetration, and invasion on PAR4-AP-modified titanium.

Visible-light promoted catalytic activity of dumbbell-like Au nanorods supported on graphene/TiO2 sheets towards hydrogenation reaction.

PubMed

Dai, Yunqian; Zhu, Mingyun; Wang, Xiaotian; Wu, Yanan; Huang, Chengqian; Fu, Wanlin; Meng, Xiangyu; Sun, Yueming

2018-06-15

In this work, the rationally-designed sharp corners on Au nanorods tremendously improved the catalytic activity, particularly in the presence of visible light irradiation, towards the hydrogenation of 4-nitrophenol to 4-aminophenol. A strikingly increased rate constant of 50.6 g -1 s -1 L was achieved in M-Au-3, which was 41.8 times higher than that of parent Au nanorods under dark conditions. The enhanced activities were proportional to the extent of the protruding sharp corners. Furthermore, remarkably enhanced activities were achieved in novel ternary Au/RGO/TiO 2 sheets, which were endowed with a 52.0 times higher rate constant than that of straight Au nanorods. These remarkably enhanced activities were even higher than those of previously reported 3-5 nm Au and 3 nm Pt nanoparticles. It was systematically observed that there are three aspects to the synergistic effects between Au and RGO sheets: (i) electron transfer from RGO to Au, (ii) a high concentration of p-nitrophenol close to dumbbell-like Au nanorods on RGO sheets, and (iii) increased local reaction temperature from the photothermal effect of both dumbbell-like Au nanorods and RGO sheets.

Visible-light promoted catalytic activity of dumbbell-like Au nanorods supported on graphene/TiO2 sheets towards hydrogenation reaction

NASA Astrophysics Data System (ADS)

Dai, Yunqian; Zhu, Mingyun; Wang, Xiaotian; Wu, Yanan; Huang, Chengqian; Fu, Wanlin; Meng, Xiangyu; Sun, Yueming

2018-06-01

In this work, the rationally-designed sharp corners on Au nanorods tremendously improved the catalytic activity, particularly in the presence of visible light irradiation, towards the hydrogenation of 4-nitrophenol to 4-aminophenol. A strikingly increased rate constant of 50.6 g‑1 s‑1 L was achieved in M-Au-3, which was 41.8 times higher than that of parent Au nanorods under dark conditions. The enhanced activities were proportional to the extent of the protruding sharp corners. Furthermore, remarkably enhanced activities were achieved in novel ternary Au/RGO/TiO2 sheets, which were endowed with a 52.0 times higher rate constant than that of straight Au nanorods. These remarkably enhanced activities were even higher than those of previously reported 3–5 nm Au and 3 nm Pt nanoparticles. It was systematically observed that there are three aspects to the synergistic effects between Au and RGO sheets: (i) electron transfer from RGO to Au, (ii) a high concentration of p-nitrophenol close to dumbbell-like Au nanorods on RGO sheets, and (iii) increased local reaction temperature from the photothermal effect of both dumbbell-like Au nanorods and RGO sheets.

Rapid Fabricating Technique for Multi-Layered Human Hepatic Cell Sheets by Forceful Contraction of the Fibroblast Monolayer

PubMed Central

Sakai, Yusuke; Koike, Makiko; Hasegawa, Hideko; Yamanouchi, Kosho; Soyama, Akihiko; Takatsuki, Mitsuhisa; Kuroki, Tamotsu; Ohashi, Kazuo; Okano, Teruo; Eguchi, Susumu

2013-01-01

Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions. PMID:23923035

The mechanistic exploration of porous activated graphene sheets-anchored SnO2 nanocrystals for application in high-performance Li-ion battery anodes.

PubMed

Yang, Yingchang; Ji, Xiaobo; Lu, Fang; Chen, Qiyuan; Banks, Craig E

2013-09-28

Porous activated graphene sheets have been for the first time exploited herein as encapsulating substrates for lithium ion battery (LIB) anodes. The as-fabricated SnO2 nanocrystals-porous activated graphene sheet (AGS) composite electrode exhibits improved electrochemical performance as an anode material for LIBs, such as better cycle performance and higher rate capability in comparison with graphene sheets, activated graphene sheets, bare SnO2 and SnO2-graphene sheet composites. The superior electrochemical performances of the designed anode can be ascribed to the porous AGS substrate, which improves the electrical conductivity of the electrode, inhibits agglomeration between particles and effectively buffers the strain from the volume variation during Li(+)-intercalation-de-intercalation and provides more cross-plane diffusion channels for Li(+) ions. As a result, the designed anode exhibits an outstanding capacity of up to 610 mA h g(-1) at a current density of 100 mA g(-1) after 50 cycles and a good rate performance of 889, 747, 607, 482 and 372 mA h g(-1) at a current density of 100, 200, 500, 1000, and 2000 mA g(-1), respectively. This work is of importance for energy storage as it provides a new substrate for the design and implementation of next-generation LIBs exhibiting exceptional electrochemical performances.

Active volcanism beneath the West Antarctic ice sheet and implications for ice-sheet stability

USGS Publications Warehouse

Blankenship, D.D.; Bell, R.E.; Hodge, S.M.; Brozena, J.M.; Behrendt, John C.; Finn, C.A.

1993-01-01

IT is widely understood that the collapse of the West Antarctic ice sheet (WAIS) would cause a global sea level rise of 6 m, yet there continues to be considerable debate about the detailed response of this ice sheet to climate change1-3. Because its bed is grounded well below sea level, the stability of the WAIS may depend on geologically controlled conditions at the base which are independent of climate. In particular, heat supplied to the base of the ice sheet could increase basal melting and thereby trigger ice streaming, by providing the water for a lubricating basal layer of till on which ice streams are thought to slide4,5. Ice streams act to protect the reservoir of slowly moving inland ice from exposure to oceanic degradation, thus enhancing ice-sheet stability. Here we present aerogeophysical evidence for active volcanism and associated elevated heat flow beneath the WAIS near the critical region where ice streaming begins. If this heat flow is indeed controlling ice-stream formation, then penetration of ocean waters inland of the thin hot crust of the active portion of the West Antarctic rift system could lead to the disappearance of ice streams, and possibly trigger a collapse of the inland ice reservoir.

Controllable curvature from planar polymer sheets in response to light.

PubMed

Hubbard, Amber M; Mailen, Russell W; Zikry, Mohammed A; Dickey, Michael D; Genzer, Jan

2017-03-22

The ability to change shape and control curvature in 3D structures starting from planar sheets can aid in assembly and add functionality to an object. Herein, we convert planar sheets of shape memory polymers (SMPs) into 3D objects with controllable curvature by dictating where the sheets shrink. Ink patterned on the surface of the sheet absorbs infrared (IR) light, resulting in localized heating, and the material shrinks locally wherever the temperature exceeds the activation temperature, T a . We introduce two different mechanisms for controlling curvature within SMP sheets. The 'direct' mechanism uses localized shrinkage to induce curvature only in regions patterned with ink. The 'indirect' mechanism uses localized shrinkage in regions patterned with ink to induce curvature in neighboring regions without ink through a balance of internal stresses. Finite element analysis predicts the final shape of the polymer sheets with excellent qualitative agreement with experimental studies. Results from this study show that curvature can be controlled by the distribution and darkness of the ink pattern on the polymer sheet. Additionally, we utilize the direct and indirect curvature mechanisms to demonstrate the formation and actuation of gripper devices, which represent the potential utility of this approach.

Development of pre-consultation prevention summary and reminder sheets for patients: preliminary study of acceptability and sustainability.

PubMed

Frank, Oliver; Aylward, Paul; Stocks, Nigel

2014-05-01

Patients attending general practices receive about 60% of indicated preventive services. Patients do not know which preventive services are indicated for them and want their GPs to offer those services. Patients arriving for consultations in three general practices received individualised prevention summary sheets. Acceptability was assessed by patient survey. Sustainability was assessed by the number of sheets printed over time. Seventy-two percent of patients discussed the advice on their sheet in the consultation, and 89% wanted to receive the sheets in the future. Practices printed 8882 sheets in the 52 weeks from the start of the trial. This new intervention seems to be acceptable and sustainable in the Australian setting. It has the potential, therefore, to increase the delivery of preventive care in general practice. A larger trial is needed to demonstrate its effect on performance of preventive activities and on patient outcomes.

Estimating erosion in a riverine watershed: Bayou Liberty-Tchefuncta River in Louisiana.

PubMed

Martin, August; Gunter, James T; Regens, James L

2003-01-01

GOAL, SCOPE, BACKGROUND: Sheet erosion from agricultural, forest and urban lands may increase stream sediment loads as well as transport other pollutants that adversely affect water quality, reduce agricultural and forest production, and increase infrastructure maintenance costs. This study uses spatial analysis techniques and a numerical modeling approach to predict areas with the greatest sheet erosion potential given different soils disturbance scenarios. A Geographic Information System (GIS) and the Universal Soil Loss Equation (USLE) were used to estimate sheet erosion from 0.64 ha parcels of land within the watershed. The Soil Survey of St. Tammany Parish, Louisiana was digitized, required soil attributes entered into the GIS database, and slope factors determined for each 80 x 80 meter parcel in the watershed. The GIS/USLE model used series-specific erosion K factors, a rainfall factor of 89, and a GIS database of scenario-driven cropping and erosion control practice factors to estimate potential soil loss due to sheet erosion. A general trend of increased potential sheet erosion occurred for all land use categories (urban, agriculture/grasslands, forests) as soil disturbance increases from cropping, logging and construction activities. Modeling indicated that rapidly growing urban areas have the greatest potential for sheet erosion. Evergreen and mixed forests (production forest) had lower sheet erosion potentials; with deciduous forests (mostly riparian) having the least sheet erosion potential. Erosion estimates from construction activities may be overestimated because of the value chosen for the erosion control practice factor. This study illustrates the ease with which GIS can be integrated with the Universal Soil Loss Equation to identify areas with high sheet erosion potential for large scale management and policy decision making. The GIS/USLE modeling approach used in this study offers a quick and inexpensive tool for estimating sheet erosion within watersheds using publicly available information. This method can quickly identify discrete locations with relatively precise spatial boundaries (approximately 80 meter resolution) that have a high sheet erosion potential as well as areas where management interventions might be appropriate to prevent or ameliorate erosion.

Current status of solar cell performance of unconventional silicon sheets

NASA Technical Reports Server (NTRS)

Yoo, H. I.; Liu, J. K.

1981-01-01

It is pointed out that activities in recent years directed towards reduction in the cost of silicon solar cells for terrestrial photovoltaic applications have resulted in impressive advancements in the area of silicon sheet formation from melt. The techniques used in the process of sheet formation can be divided into two general categories. All approaches in one category require subsequent ingot wavering. The various procedures of the second category produce silicon in sheet form. The performance of baseline solar cells is discussed. The baseline process included identification marking, slicing to size, and surface treatment (etch-polishing) when needed. Attention is also given to the performance of cells with process variations, and the effects of sheet quality on performance and processing.

TSCA Chemical Data Reporting Fact Sheet: Reporting Manufactured Chemical Substances from Metal Mining and Related Activities

EPA Pesticide Factsheets

This fact sheet provides guidance on the Chemical Data Reporting (CDR) rule requirements related to the reporting of mined metals, intermediates, and byproducts manufactured during metal mining and related activities.

Transplantation of periodontal ligament cell sheets expressing human β-defensin-3 promotes anti-inflammation in a canine model of periodontitis

PubMed Central

Zhu, Minwen; Miao, Bo; Zhu, Jianhua; Wang, Haiyan; Zhou, Zengtong

2017-01-01

Periodontitis is a chronic oral inflammatory disease caused by microorganisms. Human β-defensin-3 (HBD-3) is an endogenous antimicrobial peptide that inhibits a broad spectrum of microorganisms. Cell sheet technology has been widely applied in tissue and organ reconstructions. In the current study, it was aimed to investigate the anti-inflammatory effect of periodontal tissue engineered by HBD-3 gene-modified periodontal ligament cell (PDLC) sheets, and to identify a suitable method of promoting the regeneration of periodontal tissues. Western blot analysis and antimicrobial tests were used to confirm the expression of HBD-3. The effect of the cell sheets on anti-inflammatory activity and bone remodeling in a dog model of periodontitis was demonstrated by immunohistochemistry. The results demonstrated that the transfected PDLCs stably expressed HBD-3. Periodontal pathogens were susceptible to the antimicrobial activity of the cell sheets. In addition, the cell sheets relieved the bone resorption caused by inflammation in the in vivo model. HBD-3 may potentially be applied in the treatment of periodontitis and may function as osteogenic promoter via its anti-inflammatory effect. PMID:28944821

Transplantation of periodontal ligament cell sheets expressing human β‑defensin‑3 promotes anti‑inflammation in a canine model of periodontitis.

PubMed

Zhu, Minwen; Miao, Bo; Zhu, Jianhua; Wang, Haiyan; Zhou, Zengtong

2017-11-01

Periodontitis is a chronic oral inflammatory disease caused by microorganisms. Human β‑defensin‑3 (HBD‑3) is an endogenous antimicrobial peptide that inhibits a broad spectrum of microorganisms. Cell sheet technology has been widely applied in tissue and organ reconstructions. In the current study, it was aimed to investigate the anti‑inflammatory effect of periodontal tissue engineered by HBD‑3 gene‑modified periodontal ligament cell (PDLC) sheets, and to identify a suitable method of promoting the regeneration of periodontal tissues. Western blot analysis and antimicrobial tests were used to confirm the expression of HBD‑3. The effect of the cell sheets on anti‑inflammatory activity and bone remodeling in a dog model of periodontitis was demonstrated by immunohistochemistry. The results demonstrated that the transfected PDLCs stably expressed HBD‑3. Periodontal pathogens were susceptible to the antimicrobial activity of the cell sheets. In addition, the cell sheets relieved the bone resorption caused by inflammation in the in vivo model. HBD‑3 may potentially be applied in the treatment of periodontitis and may function as osteogenic promoter via its anti‑inflammatory effect.

Hanging on to the Wetlands. Book II.

ERIC Educational Resources Information Center

Newton, David E.; Slesnick, Irwin L.

This middle/junior high school unit on wetland ecology consists of 12 activities and activity packets containing data sheets, activity sheets, flash cards, game cards, and other materials needed to complete the activities. The first activity is the text for a slide-tape show which provides an overview of the entire unit. Each of the remaining…

Hanging on to the Wetlands. Book I.

ERIC Educational Resources Information Center

Newton, David E.; Slesnick, Irwin L.

This elementary school unit on wetland ecology consists of 12 activities and activity packets containing data sheets, activity sheets, flash cards, game cards, and other materials needed to complete the activities. The first activity is the text for a slide-tape show which provides an overview of the entire unit. Each of the remaining activities…

Electron flat-top distributions and cross-scale wave modulations observed in the current sheet of geomagnetic tail

NASA Astrophysics Data System (ADS)

Zhao, Duo; Fu, Suiyan; Parks, George K.; Sun, Weijie; Zong, Qiugang; Pan, Dongxiao; Wu, Tong

2017-08-01

We present new observations of electron distributions and the accompanying waves during the current sheet activities at ˜60 RE in the geomagnetic tail detected by the ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun) spacecraft. We find that electron flat-top distribution is a common feature near the neutral sheet of the tailward flowing plasmas, consistent with the electron distributions that are shaped in the reconnection region. Whistler mode waves are generated by the anisotropic electron temperature associated with the electron flat-top distributions. These whistler mode waves are modulated by low frequency ion scale waves that are possibly excited by the high-energy ions injected during the current sheet instability. The magnetic and electric fields of the ion scale waves are in phase with electron density variations, indicating that they are compressional ion cyclotron waves. Our observations present examples of the dynamical processes occurring during the current sheet activities far downstream of the geomagnetic tail.

Bio-sheet graft therapy for artificial gastric ulcer after endoscopic submucosal dissection: an animal feasibility study.

PubMed

Kwon, Chang-Il; Kim, Gwangil; Ko, Kwang Hyun; Jung, Yunho; Chung, Il-Kwun; Jeong, Seok; Lee, Don Haeng; Hong, Sung Pyo; Hahm, Ki Baik

2015-04-01

Various bio-sheet grafts have been attempted either to accelerate healing of artificial ulcers or to prevent adverse events after endoscopic submucosal dissection (ESD), but neither prospective nor mechanistic studies were available. To evaluate the substantial effect of a bio-sheet graft on artificial ulcer healing and its feasibility as an endoscopic treatment modality. Preclinical, in vivo animal experiment and proof-of-concept study. Animal laboratory. Three mini-pigs, Sus scrofa, mean age 14 months. Multiple ulcers sized 2.5 cm in diameter were generated by ESD in 3 mini-pigs and were assigned randomly into the following 3 groups; control group, bio-sheet group, or combination (bio-sheet plus drug) group. Bio-sheet grafts or bio-sheet plus drug combinations were applied on the artificial ulcers immediately after the ESD. Feasibility and efficacy of endoscopic bio-sheet graft therapy for the management of artificial ulcers and the evaluation of healing conditions based on histology changes in the remaining gastric bed tissues harvested from the stomachs. Thirty-three ESD specimens were obtained. On an image analysis of the ratio of healed area in the remaining gastric bed tissue compared with the matched dissected gastric mucosa, the control group showed the most significant improvement in healing activity among the 3 groups (P < .05), whereas the severity of inflammation in the remaining ulcer tissue was significantly attenuated in bio-sheet and combination groups (P < .05). Animal model. Although the bio-sheet grafts provided physical protection from gastric acid attack as reflected in the attenuated inflammation on the ulcer beds, unexpected delayed ulcer healing was noted in the bio-sheet graft group because of its physical hindrance of the healing process. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Criminal investigations and the Superfund program. Fact sheet (Final)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-09-01

The fact sheet, directed toward any one who witnesses fraudulent activity in EPA programs, discusses areas in which fraud and abuse can occur and provides an understanding of the criminal investigation process that results from reports of suspicious activity.

Strike It Rich with Classroom Compost.

ERIC Educational Resources Information Center

Jones, Linda L. Cronin

1992-01-01

Discusses composting of organic materials as an alternative to landfills. Lists uses of composts and describes details of a simple composting activity for high school students. Includes an information sheet for students and a student data sheet. Suggests other composting activities. (PR)

Hanging on to the Wetlands. Book III.

ERIC Educational Resources Information Center

Newton, David E.; Slesnick, Irwin L.

This high school unit on wetland ecology consists of 12 activities and activity packets containing data sheets, activity sheets, flash cards, game cards, and other materials needed to complete the activities. The first activity is the text for a slide-tape show which provides an overview of the entire unit. Each of the remaining activities is then…

Ice sheet radar altimetry

NASA Technical Reports Server (NTRS)

Zwally, J.

1988-01-01

The surface topography of the Greenland and Antarctic ice sheets between 72 degrees north and south was mapped using radar altimetry data from the U.S. Navy GEOSAT. The glaciological objectives of this activity were to study the dynamics of the ice flow, changes in the position of floating ice-shelf fronts, and ultimately to measure temporal changes in ice surface elevation indicative of ice sheet mass balance.

All about Me: Reproducible Activity Sheets To Develop Self-Esteem in Your Students.

ERIC Educational Resources Information Center

Palomares, Susanna

This document contains a set of reproducible activity sheets for teachers to use in enhancing the self-esteem of their students. Designed to supplement other approaches being used by teachers, the activities in this book can be used to infuse esteem-building activities into the core curriculum. The activities are organized around several…

Composite biaxially textured substrates using ultrasonic consolidation

DOEpatents

Blue, Craig A; Goyal, Amit

2013-04-23

A method of forming a composite sheet includes disposing an untextured metal or alloy first sheet in contact with a second sheet in an aligned opposing position; bonding the first sheet to the second sheet by applying an oscillating ultrasonic force to at least one of the first sheet and the second sheet to form an untextured intermediate composite sheet; and annealing the untextured intermediate composite sheet at a temperature lower than a primary re-crystallization temperature of the second sheet and higher than a primary re-crystallization temperature of the first sheet to convert the untextured first sheet into a cube textured sheet, wherein the cube texture is characterized by a .phi.-scan having a FWHM of no more than 15.degree. in all directions, the second sheet remaining untextured, to form a composite sheet.

Controlling microstructure and texture in magnesium alloy sheet by shear-based deformation processing

NASA Astrophysics Data System (ADS)

Sagapuram, Dinakar

Application of lightweight Mg sheet is limited by its low workability, both in production of sheet (typically by multistep hot and cold-rolling) and forming of sheet into components. Large strain extrusion machining (LSEM), a constrained chip formation process, is used to create Mg alloy AZ31B sheet in a single deformation step. The deformation in LSEM is shown to be intense simple shear that is confined to a narrow zone, which results in significant deformation-induced heating up to ~ 200°C and reduces the need for pre-heating to realize continuous sheet forms. This study focuses on the texture and microstructure development in the sheet processed by LSEM. Interestingly, deep, highly twinned steady-state layer develops in the workpiece subsurface due to the compressive field ahead of the shear zone. The shear deformation, in conjunction with this pre-deformed twinned layer, results in tilted-basal textures in the sheet with basal planes tilted well away from the surface. These textures are significantly different from those in rolled sheet, where basal planes are nearly parallel to the surface. By controlling the strain path, the basal plane inclination from the surface could be varied in the range of 32-53°. B-fiber (basal plane parallel to LSEM shear plane), associated with basal slip, is the major texture component in the sheet. An additional minor C2-fiber component appears above 250°C due to the thermal activation of pyramidal slip. Together with these textures, microstructure ranges from severely cold-worked to (dynamically) recrystallized type, with the corresponding grain sizes varying from ultrafine- (~ 200 nm) to fine- (2 mum) grained. Small-scale limiting dome height (LDH) confirmed enhanced formability (~ 50% increase in LDH) of LSEM sheet over the conventional rolled sheet. Premature, twinning-driven shear fractures are observed in the rolled sheet with the basal texture. In contrast, LSEM sheet with a tilted-basal texture favorably oriented for basal slip exhibits ductile tensile-type fracture. A two-fold increase in ductility is also observed for the LSEM sheet under uniaxial tensile testing without significant changes in the strength. Among texture and microstructure (grain size), texture is shown to be more critical for Mg sheet formability. However, in conjunction with a favorable texture, fine recrystallized microstructure provides for additional enhancement of strain-hardening capacity and formability. In-situ imaging of material flow during uniaxial tensile testing revealed new, interesting flow localization phenomena and fracture behavior. It is shown that the deformation behavior of Mg sheet is highly texture dependent, and also radically different from that of conventional ductile metals both in terms of necking and fracture. The implications of these observations for the LDH test results and formability of Mg sheet, in general, are briefly discussed.

Bone regeneration with osteogenic matrix cell sheet and tricalcium phosphate: An experimental study in sheep.

PubMed

Kira, Tsutomu; Akahane, Manabu; Omokawa, Shohei; Shimizu, Takamasa; Kawate, Kenji; Onishi, Tadanobu; Tanaka, Yasuhito

2017-10-18

To determine the effects of a cell sheet created from sheep bone marrow and tricalcium phosphate (TCP) on osteogenesis. Bone marrow cells were harvested from a sheep and cultured in a minimal essential medium (MEM) containing ascorbic acid phosphate (AscP) and dexamethasone (Dex). After 2 wk, the formed osteogenic matrix cell sheet was lifted from the culture dish using a scraper. Additionally, harvested bone marrow cells were cultured in MEM only as a negative control group, and in MEM with AscP, Dex, and β-glycerophosphate as a positive control group. For in vitro evaluation, we measured the alkaline phosphatase (ALP) activity and osteocalcin (OC) content in the media of the cultured cells from each group. For in vivo analysis, a porous TCP ceramic was used as a scaffold. We prepared an experimental group comprising TCP scaffolds wrapped with the osteogenic matrix cell sheets and a control group consisting of the TCP scaffold only. The constructs were implanted subcutaneously into athymic rats and the cell donor sheep, and bone formation was confirmed by histology after 4 wk. In the in vitro part, the mean ALP activity was 0.39 ± 0.03 mg/well in the negative control group, 0.67 ± 0.04 mg/well in the sheet group, and 0.65 ± 0.07 mg/well in the positive control group. The mean OC levels were 1.46 ± 0.33 ng/well in the negative control group, 3.92 ± 0.16 ng/well in the sheet group, and 4.4 ± 0.47 ng/well in the positive control group, respectively. The ALP activity and OC levels were significantly higher in the cell sheet and positive control groups than in the negative control group ( P < 0.05). There was no significant difference in ALP activity or OC levels between the cell sheet group and the positive control group ( P > 0.05). TCP constructs wrapped with cell sheets prior to implantation showed bone formation, in contrast to TCP scaffolds alone, which exhibited poor bone formation when implanted, in the subcutaneous layer both in athymic rats and in the sheep. This technique for preparing highly osteoinductive TCP may promote regeneration in large bone defects.

The Decisional Balance Sheet to Promote Healthy Behavior Among Ethnically Diverse Older Adults

PubMed Central

Geller, Karly S.; Mendoza, Ilora D.; Timbobolan, Jasah; Montjoy, Holly L.; Nigg, Claudio R.

2012-01-01

Objective The rising health care costs and increasing older adult population in the United States make preventive medicine for this age group especially crucial. Regular physical activity and fruit and vegetable consumption may prevent or delay the onset of many chronic conditions that are common among older adults. The decisional balance sheet is a promotional tool targeting the perceived pros and cons of behavior adoption. The current study tested the efficiency and effectiveness of a single-day decisional balance sheet program, targeting increased physical activity and fruit and vegetable intake among older adults. Design and Sample Participating adults (N = 21, age = 72.2) who represented a diverse population in Hawaii (Japanese = 5, Filipino = 4, Caucasian = 4, Native American = 1, Native Hawaiian = 1, Hispanic = 1, and Others = 5) were recruited from housing communities and randomized to a decisional balance sheet program adapted for physical activity or fruit and vegetable consumption. Measures Physical activity was assessed using the International Physical Activity Questionnaire (IPAQ) short form, and daily fruit and vegetable intake with the National Health and Nutrition Examination Survey single item instrument. Baseline and follow-up data were collected. Results Both programs were implemented efficiently, and participants in both groups improved their daily physical activity. The decisional balance sheet for fruit and vegetable consumption appeared less effective. Conclusions Specific suggestions for similar programs are reported. PMID:22512425

Age-related decline in the matrix contents and functional properties of human periodontal ligament stem cell sheets.

PubMed

Wu, Rui-Xin; Bi, Chun-Sheng; Yu, Yang; Zhang, Lin-Lin; Chen, Fa-Ming

2015-08-01

In this study, periodontal ligament (PDL) stem cells (PDLSCs) derived from different-aged donors were used to evaluate the effect of aging on cell sheet formation. The activity of PDLSCs was first determined based on their colony-forming ability, surface markers, proliferative/differentiative potentials, senescence-associated β-galactosidase (SA-βG) staining, and expression of pluripotency-associated transcription factors. The ability of these cells to form sheets, based on their extracellular matrix (ECM) contents and their functional properties necessary for osteogenic differentiation, was evaluated to predict the age-related changes in the regenerative capacity of the cell sheets in their further application. It was found that human PDLSCs could be isolated from the PDL tissue of different-aged subjects. However, the ability of the PDLSCs to proliferate and to undergo osteogenic differentiation and their expression of pluripotency-associated transcription factors displayed age-related decreases. In addition, these cells exhibited an age-related increase in SA-βG expression. Aged cells showed an impaired ability to form functional cell sheets, as determined by morphological observations and Ki-67 immunohistochemistry staining. Based on the production of ECM proteins, such as fibronectin, integrin β1, and collagen type I; alkaline phosphatase (ALP) activity; and the expression of osteogenic genes, such as ALP, Runt-related transcription factor 2, and osteocalcin, cell sheets formed by PDLSCs derived from older donors demonstrated a less potent osteogenic capacity compared to those formed by PDLSCs from younger donors. Our data suggest that the age-associated decline in the matrix contents and osteogenic properties of PDLSC sheets should be taken into account in cell sheet engineering research and clinical periodontal regenerative therapy. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Exposure age and ice-sheet model constraints on Pliocene East Antarctic ice sheet dynamics.

PubMed

Yamane, Masako; Yokoyama, Yusuke; Abe-Ouchi, Ayako; Obrochta, Stephen; Saito, Fuyuki; Moriwaki, Kiichi; Matsuzaki, Hiroyuki

2015-04-24

The Late Pliocene epoch is a potential analogue for future climate in a warming world. Here we reconstruct Plio-Pleistocene East Antarctic Ice Sheet (EAIS) variability using cosmogenic nuclide exposure ages and model simulations to better understand ice sheet behaviour under such warm conditions. New and previously published exposure ages indicate interior-thickening during the Pliocene. An ice sheet model with mid-Pliocene boundary conditions also results in interior thickening and suggests that both the Wilkes Subglacial and Aurora Basins largely melted, offsetting increased ice volume. Considering contributions from West Antarctica and Greenland, this is consistent with the most recent IPCC AR5 estimate, which indicates that the Pliocene sea level likely did not exceed +20 m on Milankovitch timescales. The inception of colder climate since ∼3 Myr has increased the sea ice cover and inhibited active moisture transport to Antarctica, resulting in reduced ice sheet thickness, at least in coastal areas.

Clouds enhance Greenland ice sheet meltwater runoff.

PubMed

Van Tricht, K; Lhermitte, S; Lenaerts, J T M; Gorodetskaya, I V; L'Ecuyer, T S; Noël, B; van den Broeke, M R; Turner, D D; van Lipzig, N P M

2016-01-12

The Greenland ice sheet has become one of the main contributors to global sea level rise, predominantly through increased meltwater runoff. The main drivers of Greenland ice sheet runoff, however, remain poorly understood. Here we show that clouds enhance meltwater runoff by about one-third relative to clear skies, using a unique combination of active satellite observations, climate model data and snow model simulations. This impact results from a cloud radiative effect of 29.5 (±5.2) W m(-2). Contrary to conventional wisdom, however, the Greenland ice sheet responds to this energy through a new pathway by which clouds reduce meltwater refreezing as opposed to increasing surface melt directly, thereby accelerating bare-ice exposure and enhancing meltwater runoff. The high sensitivity of the Greenland ice sheet to both ice-only and liquid-bearing clouds highlights the need for accurate cloud representations in climate models, to better predict future contributions of the Greenland ice sheet to global sea level rise.

Clouds enhance Greenland ice sheet meltwater runoff

PubMed Central

Van Tricht, K.; Lhermitte, S.; Lenaerts, J. T. M.; Gorodetskaya, I. V.; L'Ecuyer, T. S.; Noël, B.; van den Broeke, M. R.; Turner, D. D.; van Lipzig, N. P. M.

2016-01-01

The Greenland ice sheet has become one of the main contributors to global sea level rise, predominantly through increased meltwater runoff. The main drivers of Greenland ice sheet runoff, however, remain poorly understood. Here we show that clouds enhance meltwater runoff by about one-third relative to clear skies, using a unique combination of active satellite observations, climate model data and snow model simulations. This impact results from a cloud radiative effect of 29.5 (±5.2) W m−2. Contrary to conventional wisdom, however, the Greenland ice sheet responds to this energy through a new pathway by which clouds reduce meltwater refreezing as opposed to increasing surface melt directly, thereby accelerating bare-ice exposure and enhancing meltwater runoff. The high sensitivity of the Greenland ice sheet to both ice-only and liquid-bearing clouds highlights the need for accurate cloud representations in climate models, to better predict future contributions of the Greenland ice sheet to global sea level rise. PMID:26756470

Facts About Drug Abuse: Trainer's Manual.

ERIC Educational Resources Information Center

Link, William E.; And Others

Following an introductory survey of the course, this modular drug abuse trainer's manual contains all course-specified materials. These materials are: the course goals and objectives; time/activity sheets; trainer guidelines, process notes, and exercise instructions; detailed lectures and supplementary information. The time/activity sheets contain…

Supercritical CO{sub 2} mediated synthesis and catalytic activity of graphene/Pd nanocomposites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, Lulu; Nguyen, Van Hoa; Department of Chemistry, Nha Trang University, 2 Nguyen Dinh Chieu, Nha Trang

2015-11-15

Highlights: • RGO/Pd composite was efficiently prepared via a facile method in supercritical CO{sub 2}. • Graphene sheets were coated uniformly with Pd nanoparticles with a size of ∼8 nm. • Composites exhibited excellent catalytic activity in the Suzuki reaction even after 10 cycles. - Abstract: Graphene sheets were decorated with palladium nanoparticles using a facile and efficient method in supercritical CO{sub 2}. The nanoparticles were formed on the graphene sheets by the simple hydrogen reduction of palladium(II) hexafluoroacetylacetonate precursor in supercritical CO{sub 2}. The product was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electronmore » microscopy, and X-ray photoelectron spectroscopy. Highly dispersed nanoparticles with various sizes and shapes adhered well to the graphene sheets. The composites showed high catalytic activities for the Suzuki reaction under aqueous and aerobic conditions within 5 min. The effects of the different Pd precursor loadings on the catalytic activities of the composites were also examined.« less

Tug fleet and ground operations schedules and controls. Volume 2: Part 3, appendixes

NASA Technical Reports Server (NTRS)

1975-01-01

A space tug function description data sheet is prepared for each block of the space tug functional flow diagram. A summary of the basic information regarding the activities performed in its respective functional block is provided. The sheets are catalogued by functional flow block numbers with reference blocks at the end. The specific items of information contained in each data sheet are defined.

Electrical Experiments. VT-214-12-5. Part V. Transformers.

ERIC Educational Resources Information Center

Connecticut State Dept. of Education, Hartford. Div. of Vocational Education.

Designed for high school electronics students, this fifth document in a series of six electrical learning activity packages focuses on transformers. An introductory section gives the objective for the activities, an introduction, and an outline of the content. The remainder of the activity book is comprised of information sheets and job sheets on…

Temperature, Pulse, and Respiration. Instructor's Packet. Learning Activity Package.

ERIC Educational Resources Information Center

Runge, Lillian

This instructor's packet accompanies the learning activity package (LAP) on temperature, pulse, and respiration. Contents included in the packet are a time sheet, suggested uses for the LAP, an instruction sheet, final LAP reviews, a final LAP review answer key, suggested activities, an additional resources list, and student completion cards to…

Silver nanoparticles anchored reduced graphene oxide for enhanced electrocatalytic activity towards methanol oxidation

NASA Astrophysics Data System (ADS)

Kumar, Sanjeev; Mahajan, Mani; Singh, Rajinder; Mahajan, Aman

2018-02-01

In this report, silver nanoparticles (Ag NPs) anchored reduced graphene oxide (rGO) sheets (rGO/Ag) nanohybrid has been explored as anode material in direct methanol fuel cells (DMFCs). The synthesized rGO/Ag nanohybrid is characterized by XRD, XPS, FTIR spectroscopy and HRTEM techniques. Cyclic voltammograms demonstrate that the rGO/Ag nanohybrid exhibits higher electrocatalytic activity in comparison to rGO sheets for methanol oxidation reaction (MOR). This enhancement is attributed to the synergetic effect produced by the presence of more active sites provided by Ag NPs anchored on a conducting network of large surface area rGO sheets.

Process to produce lithium-polymer batteries

DOEpatents

MacFadden, Kenneth Orville

1998-01-01

A polymer bonded sheet product suitable for use as an electrode in a non-aqueous battery system. A porous electrode sheet is impregnated with a solid polymer electrolyte, so as to diffuse into the pores of the electrode. The composite is allowed to cool, and the electrolyte is entrapped in the porous electrode. The sheet products composed have the solid polymer electrolyte composition diffused into the active electrode material by melt-application of the solid polymer electrolyte composition into the porous electrode material sheet. The solid polymer electrolyte is maintained at a temperature that allows for rapid diffusion into the pores of the electrode. The composite electrolyte-electrode sheets are formed on current collectors and can be coated with solid polymer electrolyte prior to battery assembly. The interface between the solid polymer electrolyte composite electrodes and the solid polymer electrolyte coating has low resistance.

Structural, electronic structure and antibacterial properties of graphene-oxide nano-sheets

NASA Astrophysics Data System (ADS)

Sharma, Aditya; Varshney, Mayora; Nanda, Sitansu Sekhar; Shin, Hyun Joon; Kim, Namdong; Yi, Dong Kee; Chae, Keun-Hwa; Ok Won, Sung

2018-04-01

Correlation between the structural/electronic structure properties and bio-activity of graphene-based materials need to be thoroughly evaluated before their commercial implementation in the health and environment precincts. To better investigate the local hybridization of sp2/sp3 orbitals of the functional groups of graphene-oxide (GO) and their execution in the antimicrobial mechanism, we exemplify the antibacterial activity of GO sheets towards the Escherichia coli bacteria (E. coli) by applying the field-emission scanning electron microscopy (FESEM), near edge X-ray absorption fine structure (NEXAFS) and scanning transmission X-ray microscope (STXM) techniques. C K-edge and O K-edge NEXAFS spectra have revealed lesser sp2 carbon atoms in the aromatic ring and attachment of functional oxygen groups at GO sheets. Entrapment of E. coli bacteria by GO sheets is evidenced by FESEM investigations and has also been corroborated by nano-scale imaging of bacteria using the STXM. Spectroscopy evidence of functional oxygen moieties with GO sheets and physiochemical entrapment of E. coli bacteria have assisted us to elaborate the mechanism of cellular oxidative stress-induced disruption of bacterial membrane.

37 CFR 1.76 - Application data sheet.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Application data sheet. 1.76... Application data sheet. (a) Application data sheet. An application data sheet is a sheet or sheets, that may... bibliographic data, arranged in a format specified by the Office. An application data sheet must be titled...

Evolution of three-dimensional relativistic current sheets and development of self-generated turbulence

NASA Astrophysics Data System (ADS)

Takamoto, M.

2018-05-01

In this paper, the temporal evolution of three-dimensional relativistic current sheets in Poynting-dominated plasma is studied for the first time. Over the past few decades, a lot of efforts have been conducted on studying the evolution of current sheets in two-dimensional space, and concluded that sufficiently long current sheets always evolve into the so-called plasmoid chain, which provides a fast reconnection rate independent of its resistivity. However, it is suspected that plasmoid chain can exist only in the case of two-dimensional approximation, and would show transition to turbulence in three-dimensional space. We performed three-dimensional numerical simulation of relativistic current sheet using resistive relativistic magnetohydrodynamic approximation. The results showed that the three-dimensional current sheets evolve not into plasmoid chain but turbulence. The resulting reconnection rate is 0.004, which is much smaller than that of plasmoid chain. The energy conversion from magnetic field to kinetic energy of turbulence is just 0.01 per cent, which is much smaller than typical non-relativistic cases. Using the energy principle, we also showed that the plasmoid is always unstable for a displacement in the opposite direction to its acceleration, probably interchange-type instability, and this always results in seeds of turbulence behind the plasmoids. Finally, the temperature distribution along the sheet is discussed, and it is found that the sheet is less active than plasmoid chain. Our finding can be applied for many high-energy astrophysical phenomena, and can provide a basic model of the general current sheet in Poynting-dominated plasma.

FSA future directions: FSA technology activities in FY86

NASA Technical Reports Server (NTRS)

Leipold, M. H.

1985-01-01

The silicon material, advanced silicon sheet, device research, and process research activities are explained. There will be no new initiatives. Many activities are targeted for completion and the emphasis will then be on technology transfer. Industrial development of the fluidized-bed reactor (FBR) deposition technology is proceeding. Technology transfer and industry funding of sheet development are continuing.

Health and Nutrition Curriculum. Informative and Fun for K-8!

ERIC Educational Resources Information Center

National Heart Savers Association, Omaha, NE.

This health and nutrition curriculum for students in grades K-8 teaches students good health habits in order to improve their quality of life. The curriculum consists of a series of activity sheets that offer entertaining and educational activities designed to motivate students to learn while they have fun. Each activity sheet contains a…

The decisional balance sheet to promote healthy behavior among ethnically diverse older adults.

PubMed

Geller, Karly S; Mendoza, Ilora D; Timbobolan, Jasah; Montjoy, Holly L; Nigg, Claudio R

2012-01-01

The rising health care costs and increasing older adult population in the United States make preventive medicine for this age group especially crucial. Regular physical activity and fruit and vegetable consumption may prevent or delay the onset of many chronic conditions that are common among older adults. The decisional balance sheet is a promotional tool targeting the perceived pros and cons of behavior adoption. The current study tested the efficiency and effectiveness of a single-day decisional balance sheet program, targeting increased physical activity and fruit and vegetable intake among older adults. Participating adults (N = 21, age = 72.2) who represented a diverse population in Hawaii (Japanese = 5, Filipino = 4, Caucasian = 4, Native American = 1, Native Hawaiian = 1, Hispanic = 1, and Others = 5) were recruited from housing communities and randomized to a decisional balance sheet program adapted for physical activity or fruit and vegetable consumption. Physical activity was assessed using the International Physical Activity Questionnaire (IPAQ) short form, and daily fruit and vegetable intake with the National Health and Nutrition Examination Survey single item instrument. Baseline and follow-up data were collected. Both programs were implemented efficiently, and participants in both groups improved their daily physical activity. The decisional balance sheet for fruit and vegetable consumption appeared less effective. Specific suggestions for similar programs are reported. © 2011 Wiley Periodicals, Inc.

Metallic tin quantum sheets confined in graphene toward high-efficiency carbon dioxide electroreduction

NASA Astrophysics Data System (ADS)

Lei, Fengcai; Liu, Wei; Sun, Yongfu; Xu, Jiaqi; Liu, Katong; Liang, Liang; Yao, Tao; Pan, Bicai; Wei, Shiqiang; Xie, Yi

2016-09-01

Ultrathin metal layers can be highly active carbon dioxide electroreduction catalysts, but may also be prone to oxidation. Here we construct a model of graphene confined ultrathin layers of highly reactive metals, taking the synthetic highly reactive tin quantum sheets confined in graphene as an example. The higher electrochemical active area ensures 9 times larger carbon dioxide adsorption capacity relative to bulk tin, while the highly-conductive graphene favours rate-determining electron transfer from carbon dioxide to its radical anion. The lowered tin-tin coordination numbers, revealed by X-ray absorption fine structure spectroscopy, enable tin quantum sheets confined in graphene to efficiently stabilize the carbon dioxide radical anion, verified by 0.13 volts lowered potential of hydroxyl ion adsorption compared with bulk tin. Hence, the tin quantum sheets confined in graphene show enhanced electrocatalytic activity and stability. This work may provide a promising lead for designing efficient and robust catalysts for electrolytic fuel synthesis.

Micro-fluidic partitioning between polymeric sheets for chemical amplification and processing

DOEpatents

Anderson, Brian L.

2017-01-24

A system for fluid partitioning for chemical amplification or other chemical processing or separations of a sample, comprising a first dispenser of a first polymeric sheet, wherein the first polymeric sheet contains chambers; a second dispenser of a second polymeric sheet wherein the first dispenser and the second dispenser are positioned so that the first polymeric sheet and the second polymeric sheet become parallel; a dispenser of the fluid positioned to dispense the fluid between the first polymeric sheet and the second polymeric sheet; and a seal unit that seals the first polymeric sheet and the second polymeric sheet together thereby sealing the sample between the first polymeric sheet and the second polymeric sheet and partitioning the fluid for chemical amplification or other chemical processing or separations.

Micro-fluidic partitioning between polymeric sheets for chemical amplification and processing

DOEpatents

Anderson, Brian L.

2015-05-26

A system for fluid partitioning for chemical amplification or other chemical processing or separations of a sample, comprising a first dispenser of a first polymeric sheet, wherein the first polymeric sheet contains chambers; a second dispenser of a second polymeric sheet wherein the first dispenser and the second dispenser are positioned so that the first polymeric sheet and the second polymeric sheet become parallel; a dispenser of the fluid positioned to dispense the fluid between the first polymeric sheet and the second polymeric sheet; and a seal unit that seals the first polymeric sheet and the second polymeric sheet together thereby sealing the sample between the first polymeric sheet and the second polymeric sheet and partitioning the fluid for chemical amplification or other chemical processing or separations.

Process to produce lithium-polymer batteries

DOEpatents

MacFadden, K.O.

1998-06-30

A polymer bonded sheet product is described suitable for use as an electrode in a non-aqueous battery system. A porous electrode sheet is impregnated with a solid polymer electrolyte, so as to diffuse into the pores of the electrode. The composite is allowed to cool, and the electrolyte is entrapped in the porous electrode. The sheet products composed have the solid polymer electrolyte composition diffused into the active electrode material by melt-application of the solid polymer electrolyte composition into the porous electrode material sheet. The solid polymer electrolyte is maintained at a temperature that allows for rapid diffusion into the pores of the electrode. The composite electrolyte-electrode sheets are formed on current collectors and can be coated with solid polymer electrolyte prior to battery assembly. The interface between the solid polymer electrolyte composite electrodes and the solid polymer electrolyte coating has low resistance. 1 fig.

Observations of the Formation, Development, and Structure of a Current Sheet in an Eruptive Solar Flare

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seaton, Daniel B.; Darnel, Jonathan M.; Bartz, Allison E., E-mail: daniel.seaton@noaa.gov

2017-02-01

We present Atmospheric Imaging Assembly observations of a structure we interpret as a current sheet associated with an X4.9 flare and coronal mass ejection that occurred on 2014 February 25 in NOAA Active Region 11990. We characterize the properties of the current sheet, finding that the sheet remains on the order of a few thousand kilometers thick for much of the duration of the event and that its temperature generally ranged between 8 and 10 MK. We also note the presence of other phenomena believed to be associated with magnetic reconnection in current sheets, including supra-arcade downflows and shrinking loops.more » We estimate that the rate of reconnection during the event was M{sub A} ≈ 0.004–0.007, a value consistent with model predictions. We conclude with a discussion of the implications of this event for reconnection-based eruption models.« less

Observed use of voluntary controls to reduce physical exposures among sheet metal workers of the mechanical trade

PubMed Central

Dale, Ann Marie; Miller, Kim; Gardner, Bethany T.; Hwang, Ching-Ting; Evanoff, Bradley; Welch, Laura

2015-01-01

Introduction Little is known about the transfer into the workplace of interventions designed to reduce the physical demands of sheet metal workers. Methods We reviewed videos from a case series of 15 sheet metal worksite assessments performed in 2007–2009 to score postures and physical loads, and to observe the use of recommended interventions to reduce physical exposures in sheet metal activities made by a NIOSH stakeholder meeting in 2002. Results Workers showed consistent use of material handling devices, but we observed few uses of recommended interventions to reduce exposures during overhead work. Workers spent large proportions of time in awkward shoulder elevation and low back rotation postures. Conclusions In addition to the development of new technologies and system designs, increased adoption of existing tools and practices could reduce time spent in awkward postures and other risks for musculoskeletal disorders in sheet metal work. PMID:26360196

Heating and cooling of the earth's plasma sheet

NASA Technical Reports Server (NTRS)

Goertz, C. K.

1990-01-01

Magnetic-field models based on pressure equilibrium in the quiet magnetotail require nonadiabatic cooling of the plasma as it convects inward or a decrease of the flux tube content. Recent in situ observations of plasma density and temperature indicate that, during quiet convection, the flux tube content may actually increase. Thus the plasma must be cooled during quiet times. The earth plasma sheet is generally significantly hotter after the expansion phase of a substorm than before the plasma sheet thinning begins and cools during the recovery phase. Heating mechanisms such as reconnection, current sheet acceleration, plasma expansion, and resonant absorption of surface waves are discussed. It seems that all mechanisms are active, albeit in different regions of the plasma sheet. Near-earth tail signatures of substorms require local heating as well as a decrease of the flux tube content. It is shown that the resonant absorption of surface waves can provide both.

Fingerprinting of music scores

NASA Astrophysics Data System (ADS)

Irons, Jonathan; Schmucker, Martin

2004-06-01

Publishers of sheet music are generally reluctant in distributing their content via the Internet. Although online sheet music distribution's advantages are numerous the potential risk of Intellectual Property Rights (IPR) infringement, e.g. illegal online distributions, disables any innovation propensity. While active protection techniques only deter external risk factors, additional technology is necessary to adequately treat further risk factors. For several media types including music scores watermarking technology has been developed, which ebeds information in data by suitable data modifications. Furthermore, fingerprinting or perceptual hasing methods have been developed and are being applied especially for audio. These methods allow the identification of content without prior modifications. In this article we motivate the development of watermarking and fingerprinting technologies for sheet music. Outgoing from potential limitations of watermarking methods we explain why fingerprinting methods are important for sheet music and address potential applications. Finally we introduce a condept for fingerprinting of sheet music.

The Influence of Alternating Low-Cycle Bending Loads on Sheet Properties Having an Hcp Crystal Lattice

NASA Astrophysics Data System (ADS)

Demler, Eugen; Rodman, Dmytro; Rodman, Mykhailo; Gerstein, Gregory; Grydin, Olexandr; Briukhanov, Arkadiy A.; Klose, Christian; Nürnberger, Florian; Maier, Hans Jürgen

2018-02-01

The process of cyclic bending was investigated using thin sheets of the magnesium alloy AZ31 and α-titanium. These materials possess an hcp crystal lattice with different c/a ratios. It turned out that the latter have a substantial influence on the sheet deformation behavior. Even for small deformations (up to 2% strain), a large influence on the yield stress was present for both materials. In addition, cyclic bending contributes to the activation of prismatic slip, which is accompanied by twinning and detwinning. The changes in sheet anisotropy following cyclic bending were determined using texture measurements. Specifically, the AZ31 alloy sheets exhibited a considerable change in anisotropy of the mechanical properties with an increasing number of bending cycles. The anisotropy in the yield stress increases from 15% in the initial condition to 40% after three cycles. For the α-titanium sheet, the change in anisotropy was approx. 26% less. In general, the largest changes in properties occurred already in the first bending cycle and a stabilization took place upon further cycling.

Enhanced photocatalytic activity and structural stability by hybridizing Ag3PO4 nanospheres with graphene oxide sheets.

PubMed

Liang, Qinghua; Shi, Yao; Ma, Wangjing; Li, Zhi; Yang, Xinmin

2012-12-05

Graphene oxide (GO)-Ag(3)PO(4) nanocomposites synthesized through a facile solution approach via electrostatic interaction were investigated as excellent photocatalysts for the degradation of rhodamine B (RhB) under visible light irradiation. SEM and TEM observations indicate that Ag(3)PO(4) nanospheres of ~120 nm in diameter were well dispersed and anchored onto the exfoliated GO sheets. The characterizations of FTIR and Raman demonstrated the existence of strong charge interactions between GO sheets and Ag(3)PO(4) nanospheres. As compared to Ag(3)PO(4) nanospheres alone, the attachments of GO sheets led to a band gap narrowing (2.10 eV) and a strong absorbance in the near infrared region (NIR). The photoluminescence (PL) analysis indicates a more efficient separation of electron-hole pairs in the GO-Ag(3)PO(4) nanocomposites. Notably, the incorporation of GO sheets not only significantly enhances the photocatalytic activity but also improves the structural stability of Ag(3)PO(4). The positive synergistic effects between Ag(3)PO(4) nanospheres and GO sheets are proposed to contribute to the improved photocatalytic properties. A possible photocatalytic mechanism of the GO-Ag(3)PO(4) nanocomposites was assumed as well. The integration of these advantages enables such GO-Ag(3)PO(4) hybrid material to be a nice photocatalyst for broad applications in a sewage treatment system.

Widespread surface meltwater drainage in Antarctica

NASA Astrophysics Data System (ADS)

Kingslake, J.; Ely, J.; Das, I.; Bell, R. E.

2016-12-01

Surface meltwater is thought to cause ice-shelf disintegration, which accelerates the contribution of ice sheets to sea-level rise. Antarctic surface melting is predicted to increase and trigger further ice-shelf disintegration during this century. These climate-change impacts could be modulated by an active hydrological network analogous to the one in operation in Greenland. Despite some observations of Antarctic surface and sub-surface hydrological systems, large-scale active surface drainage in Antarctica has rarely been studied. We use satellite imagery and aerial photography to reveal widespread active hydrology on the surface of the Antarctic Ice Sheet as far south as 85o and as high as 1800 m a.s.l., often near mountain peaks that protrude through the ice (nunataks) and relatively low-albedo `blue-ice areas'. Despite predominantly sub-zero regional air temperatures, as simulated by a regional climate model, Antarctic active drainage has persisted for decades, transporting water through surface streams and feeding vast melt ponds up to 80 km long. Drainage networks (the largest are over 100 km in length) form on flat ice shelves, steep outlet glaciers and ice-sheet flanks across the West and East Antarctica Ice Sheets. Motivated by the proximity of many drainage systems to low-albedo rock and blue-ice areas, we hypothesize a positive feedback between exposed-rock extent, BIA formation, melting and ice-sheet thinning. This feedback relies on drainage moving water long distances from areas near exposed rock, across the grounding line onto and across ice shelves - a process we observe, but had previously thought to be unlikely in Antarctica. This work highlights previously-overlooked processes, not captured by current regional-scale models, which may accelerate the retreat of the Antarctic Ice Sheet.

The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries: Plasma Sheet Ion Composition

DOE PAGES

Denton, M. H.; Thomsen, M. F.; Reeves, G. D.; ...

2017-10-03

The ion plasma sheet (~few hundred eV to ~few 10s keV) is usually dominated by H + ions. Here, changes in ion composition within the plasma sheet are explored both during individual events, and statistically during 54 calm-to-storm events and during 21 active-to-calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial and temporal resolution of the H +, O +, and He + ion fluxes in the plasma sheet. H+ shown to be the dominant ion in the plasma sheet in the calm-to-storm transition. However, the energy-flux ofmore » each ion changes in a quasi-linear manner during extended calm intervals. Heavy ions (O + and He +) become increasingly important during such periods as charge-exchange reactions result in faster loss for H + than for O + or He +. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of: (a) the composition of previously injected plasma at the onset of calm conditions, and (b) use of simple drift-physics models combined with calculations of charge-exchange losses.« less

The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries: Plasma Sheet Ion Composition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denton, M. H.; Thomsen, M. F.; Reeves, G. D.

The ion plasma sheet (~few hundred eV to ~few 10s keV) is usually dominated by H + ions. Here, changes in ion composition within the plasma sheet are explored both during individual events, and statistically during 54 calm-to-storm events and during 21 active-to-calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial and temporal resolution of the H +, O +, and He + ion fluxes in the plasma sheet. H+ shown to be the dominant ion in the plasma sheet in the calm-to-storm transition. However, the energy-flux ofmore » each ion changes in a quasi-linear manner during extended calm intervals. Heavy ions (O + and He +) become increasingly important during such periods as charge-exchange reactions result in faster loss for H + than for O + or He +. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of: (a) the composition of previously injected plasma at the onset of calm conditions, and (b) use of simple drift-physics models combined with calculations of charge-exchange losses.« less

Size and weight graded multi-ply laminar electrodes

DOEpatents

Liu, Chia-Tsun; Demczyk, Brian G.; Rittko, Irvin R.

1984-01-01

An electrode is made comprising a porous backing sheet, and attached thereto a catalytically active layer having an electrolyte permeable side and a backing layer contacting side, where the active layer comprises a homogeneous mixture of active hydrophobic and hydrophilic agglomerates with catalyst disposed equally throughout the active layer, and where the agglomerate size increases from the electrolyte permeable side to the backing sheet contacting side.

Expanding Adolescent Role Expectations. Information, Activities, Resources for Vocational Educators.

ERIC Educational Resources Information Center

Cornell Univ., Ithaca, NY. Dept. of Community Service Education.

Developed for vocational educators as a self-study guide or as a basis for inservice workshops, this source book presents information on sex fair education. Each of the six sections contains fact sheets and references, and some contain checklists, guidelines or rating sheets, and highlighted questions and activities which may be used for…

Mean-field theory of active electrolytes: Dynamic adsorption and overscreening

NASA Astrophysics Data System (ADS)

Frydel, Derek; Podgornik, Rudolf

2018-05-01

We investigate active electrolytes within the mean-field level of description. The focus is on how the double-layer structure of passive, thermalized charges is affected by active dynamics of constituting ions. One feature of active dynamics is that particles adhere to hard surfaces, regardless of chemical properties of a surface and specifically in complete absence of any chemisorption or physisorption. To carry out the mean-field analysis of the system that is out of equilibrium, we develop the "mean-field simulation" technique, where the simulated system consists of charged parallel sheets moving on a line and obeying active dynamics, with the interaction strength rescaled by the number of sheets. The mean-field limit becomes exact in the limit of an infinite number of movable sheets.

Publications - AR 1981 | Alaska Division of Geological & Geophysical

Science.gov Websites

Sheets Maps & Other Oversized Sheets Plate 1 Significant mineral deposits and prospects in Alaska (6.8 M) Plate 2 Major active claim blocks and development projects in Alaska, scale 1:42,240 (13.0 M

Evaluation of the McFann, Gray & Associates’ BSEP (Basic Skills Education Program) 2. Curriculum

DTIC Science & Technology

1985-08-01

167 APPENDIX A - Tables APPENDIX B - Student Record Sheets, Module Record Sheets, Classroom Observation Form, and Questionnaires iv LIST OF...course data and demographic data about students, and classroom observation forms for recording classroom activities), * attended teacher-training...5.3% 27.5% (29) (7) (36) >=9.0 18.3% 54.2% 72.5% (24) (71) (95) Total 40.5% 59.5% 100% (53) (78) (131) ell APPENDIX B 4., ’-o CLASSROOM OBSERVATION SHEET

Self-enhanced catalytic activities of functionalized graphene sheets in the combustion of nitromethane: molecular dynamic simulations by molecular reactive force field.

PubMed

Zhang, Chaoyang; Wen, Yushi; Xue, Xianggui

2014-08-13

Functionalized graphene sheet (FGS) is a promising additive that enhances fuel/propellant combustion, and the determination of its mechanism has attracted much interest. In the present study, a series of molecular dynamic simulations based on a reactive force field (ReaxFF) are performed to explore the catalytic activity (CA) of FGS in the thermal decay of nitromethane (NM, CH3NO2). FGSs and pristine graphene sheets (GSs) are oxidized in hot NM liquid to increase their functionalities and subsequently show self-enhanced CAs during the decay. The CAs result from the interatomic exchanges between the functional groups on the sheets and the NM liquid, i.e., mainly between H and O atoms. CA is dependent on the density of NM, functionalities of sheets, and temperature. The GSs and FGSs that originally exhibit different functionalities tend to possess similar functionalities and consequently similar CAs as temperature increases. Other carbon materials and their oxides can accelerate combustion of other fuels/propellants similar to NM, provided that they can be dispersed and their key reaction steps in combustion are similar to NM.

Method for heating, forming and tempering a glass sheet

DOEpatents

Boaz, Premakaran Tucker; Sitzman, Gary W.

1998-01-01

A method for heating, forming and tempering a glass sheet including the steps of heating at least one glass sheet to at least a first predetermined temperature, applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature, forming the glass sheet to a predetermined configuration, and cooling an outer surface of the glass sheet to at least a third predetermined temperature to temper the glass sheet.

Hand-Drawn 'Weekly Information Sheets' Focus Teaching, Engage Students, and Improve Communication

NASA Astrophysics Data System (ADS)

Pound, K. S.

2016-12-01

Hand-drawn and lettered `Weekly Information Sheets' (WIS) were created on a weekly basis for an upper-level Sedimentology & Stratigraphy class. Use of these sheets resulted in improved work quality, attention to detail, communication skills, and overall engagement. The sheets were modeled on the work of Lynda Barry (https://www.drawnandquarterly.com/syllabus), and included a series of repeated elements: goofy/absurd newspaper clippings, marginally pertinent cartoon(s), a summary of the weeks activities / goals and lectures, as well as cartoon cat, mouse and penguin drawings with innane comments, quotes and general class reminders. The pedagogical aims for these weekly sheets were multifold. First, they were designed so that students could see the time and care I put in to the sheet - my hope was that this would show the time and care I expected them to put in to their work. Second, I wanted to create something students would take the time to read - despite this being a 400-level class, students are rarely diligent about reading a typewritten handout. Third, I wanted to have a vehicle for engaging them in the larger world, including ethical or moral dilemmas. Fourth, I wanted the students to reflectively consider the nature of communication in science. Finally, I wanted a mechanism to focus my thoughts on the teaching and learning for the upcoming week that went beyond simply reviewing my notes and activities. Student response to the WIS was positive; they read them, used them for organizing their class notes and exam review. Students arrived early for class on Mondays for the WIS - although I needed to give them time to read the sheet. Comparison with previous course offerings shows improvements in student communication skills (written reports, poster presentation) and overall achievement.

Ice_Sheets_CCI: Essential Climate Variables for the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Forsberg, R.; Sørensen, L. S.; Khan, A.; Aas, C.; Evansberget, D.; Adalsteinsdottir, G.; Mottram, R.; Andersen, S. B.; Ahlstrøm, A.; Dall, J.; Kusk, A.; Merryman, J.; Hvidberg, C.; Khvorostovsky, K.; Nagler, T.; Rott, H.; Scharrer, M.; Shepard, A.; Ticconi, F.; Engdahl, M.

2012-04-01

As part of the ESA Climate Change Initiative (www.esa-cci.org) a long-term project "ice_sheets_cci" started January 1, 2012, in addition to the existing 11 projects already generating Essential Climate Variables (ECV) for the Global Climate Observing System (GCOS). The "ice_sheets_cci" goal is to generate a consistent, long-term and timely set of key climate parameters for the Greenland ice sheet, to maximize the impact of European satellite data on climate research, from missions such as ERS, Envisat and the future Sentinel satellites. The climate parameters to be provided, at first in a research context, and in the longer perspective by a routine production system, would be grids of Greenland ice sheet elevation changes from radar altimetry, ice velocity from repeat-pass SAR data, as well as time series of marine-terminating glacier calving front locations and grounding lines for floating-front glaciers. The ice_sheets_cci project will involve a broad interaction of the relevant cryosphere and climate communities, first through user consultations and specifications, and later in 2012 optional participation in "best" algorithm selection activities, where prototype climate parameter variables for selected regions and time frames will be produced and validated using an objective set of criteria ("Round-Robin intercomparison"). This comparative algorithm selection activity will be completely open, and we invite all interested scientific groups with relevant experience to participate. The results of the "Round Robin" exercise will form the algorithmic basis for the future ECV production system. First prototype results will be generated and validated by early 2014. The poster will show the planned outline of the project and some early prototype results.

Welding.

ERIC Educational Resources Information Center

Cowan, Earl; And Others

The curriculum guide for welding instruction contains 16 units presented in six sections. Each unit is divided into the following areas, each of which is color coded: terminal objectives, specific objectives, suggested activities, and instructional materials; information sheet; transparency masters; assignment sheet; test; and test answers. The…

Method for heating, forming and tempering a glass sheet

DOEpatents

Boaz, P.T.; Sitzman, G.W.

1998-10-27

A method for heating, forming and tempering a glass sheet is disclosed including the steps of heating at least one glass sheet to at least a first predetermined temperature, applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature, forming the glass sheet to a predetermined configuration, and cooling an outer surface of the glass sheet to at least a third predetermined temperature to temper the glass sheet. 2 figs.

Imaging a seizure model in zebrafish with structured illumination light sheet microscopy

NASA Astrophysics Data System (ADS)

Liu, Yang; Dale, Savannah; Ball, Rebecca; VanLeuven, Ariel J.; Baraban, Scott; Sornborger, Andrew; Lauderdale, James D.; Kner, Peter

2018-02-01

Zebrafish are a promising vertebrate model for elucidating how neural circuits generate behavior under normal and pathological conditions. The Baraban group first demonstrated that zebrafish larvae are valuable for investigating seizure events and can be used as a model for epilepsy in humans. Because of their small size and transparency, zebrafish embryos are ideal for imaging seizure activity using calcium indicators. Light-sheet microscopy is well suited to capturing neural activity in zebrafish because it is capable of optical sectioning, high frame rates, and low excitation intensities. We describe work in our lab to use light-sheet microscopy for high-speed long-time imaging of neural activity in wildtype and mutant zebrafish to better understand the connectivity and activity of inhibitory neural networks when GABAergic signaling is altered in vivo. We show that, with light-sheet microscopy, neural activity can be recorded at 23 frames per second in twocolors for over 10 minutes allowing us to capture rare seizure events in mutants. We have further implemented structured illumination to increase resolution and contrast in the vertical and axial directions during high-speed imaging at an effective frame rate of over 7 frames per second.

Polymer based nanocomposites with nanofibers and exfoliated clay

NASA Technical Reports Server (NTRS)

Meador, Michael A.; Reneker, Darrell H.

2005-01-01

Polymer solutions, containing clay sheets, were electrospun into nanofibers and microfibers that contained clay sheets inside. Controllable removal of polymer by plasma etching from the surface of fibers revealed the arrangement of clay. The shape, flexibility, size distribution and arrangement of clay sheets were observed by transmission and scanning electron microscopy. The clay sheets were partially aligned in big fibers with normal direction of clay sheets perpendicular to fiber axis. Crumpling of clay sheets inside fibers was observed when the fiber diameter was comparable to the lateral size of clay sheets. Single sheets of clay were observed both by catching clay sheets dispersed in water with electrospun nanofiber mats and by the deliberate removal of most of the polymer in the fibers. Thin, flexible gas barrier films, that are reasonably strong, were assembled from clay sheets and polymer nanofibers. Structure of composite films was characterized with scanning electron microscopy. Continuous film of clay sheets were physically attached to the surface of fiber mats. Spincoating film of polymer and clay sheets was reinforced by electrospun fiber scaffold. Certain alignment of clay sheets was observed in the vicinity of fibers.

Space Vehicle Valve System

NASA Technical Reports Server (NTRS)

Kelley, Anthony R. (Inventor); Lindner, Jeffrey L. (Inventor)

2014-01-01

The present invention is a space vehicle valve system which controls the internal pressure of a space vehicle and the flow rate of purged gases at a given internal pressure and aperture site. A plurality of quasi-unique variable dimension peaked valve structures cover the purge apertures on a space vehicle. Interchangeable sheet guards configured to cover valve apertures on the peaked valve structure contain a pressure-activated surface on the inner surface. Sheet guards move outwardly from the peaked valve structure when in structural contact with a purge gas stream flowing through the apertures on the space vehicle. Changing the properties of the sheet guards changes the response of the sheet guards at a given internal pressure, providing control of the flow rate at a given aperture site.

Ice-sheet response to oceanic forcing.

PubMed

Joughin, Ian; Alley, Richard B; Holland, David M

2012-11-30

The ice sheets of Greenland and Antarctica are losing ice at accelerating rates, much of which is a response to oceanic forcing, especially of the floating ice shelves. Recent observations establish a clear correspondence between the increased delivery of oceanic heat to the ice-sheet margin and increased ice loss. In Antarctica, most of these processes are reasonably well understood but have not been rigorously quantified. In Greenland, an understanding of the processes by which warmer ocean temperatures drive the observed retreat remains elusive. Experiments designed to identify the relevant processes are confounded by the logistical difficulties of instrumenting ice-choked fjords with actively calving glaciers. For both ice sheets, multiple challenges remain before the fully coupled ice-ocean-atmosphere models needed for rigorous sea-level projection are available.

Dehydrofreezing of Fish I

NASA Astrophysics Data System (ADS)

Kozima, Tsuneo

Recently, new method of removing water from perishable food were developed using dehydration sheet with material having high osmotic pressure and absorbent polymer. Dehydration sheet consist of mixture of sugar dehydrolysate and absorbent polymer covered with sem-permeable membrane, and can remove water in liquid state by contact with perishable food. Dehydration rate of fish using with dehydration sheet varied depending on species, their shape, and ambient temperature etc. Fish were dehydrated with dehydration sheet at low temperature as 0 - 5 C and frozen in cold storage room. Dehydrofrozen fish were kept it's high quality and freshness after thawing, ATPase activity of fish muscle was kept at high level after dehydrofreezing in the case of cod and alaska pollack, and flesh color of farming salmon was kept after thawing.

Surface Passivation by Quantum Exclusion Using Multiple Layers

NASA Technical Reports Server (NTRS)

Hoenk, Michael E. (Inventor)

2015-01-01

A semiconductor device has a multilayer doping to provide improved passivation by quantum exclusion. The multilayer doping includes at least two doped layers fabricated using MBE methods. The dopant sheet densities in the doped layers need not be the same, but in principle can be selected to be the same sheet densities or to be different sheet densities. The electrically active dopant sheet densities are quite high, reaching more than 1.times.10.sup.14 cm.sup.-2, and locally exceeding 10.sup.22 per cubic centimeter. It has been found that silicon detector devices that have two or more such dopant layers exhibit improved resistance to degradation by UV radiation, at least at wavelengths of 193 nm, as compared to conventional silicon p-on-n devices.

The Potato People in "School Daze": Presented by Theatre Beyond Words. Cue Sheet for Students.

ERIC Educational Resources Information Center

Briley, Rachel

This performance guide is designed for teachers to use with students before and after a performance of the Potato People in "School Daze." The guide, called a "Cuesheet," contains seven pages of reproducible activity sheets for use in class with activities and discussion questions on the following topics: (1) Meet the…

Teen Sexual Activity, Pregnancy and Childbearing among Latinos in the United States. Fact Sheet.

ERIC Educational Resources Information Center

National Campaign To Prevent Teen Pregnancy, Washington, DC.

The Latino population is the fastest-growing major racial/ethnic group in the United States. By 2020, approximately 16 percent of the population will be Latino. This increase will be even more pronounced among teens. This fact sheet summarizes data from the National Vital Statistics Reports on reported sexual activity, pregnancy rates, and…

Moral Dilemmas/Value Sheets: Writing for Content-Centered Social Studies Classrooms.

ERIC Educational Resources Information Center

Stahl, Robert J.; And Others

The purpose of the paper is to stress the development of content-centered classroom activities useful for attaining values clarification and/or moral development goals. The objective is to help teachers understand the formulation of content-centered learning activities so that they will be able to plan and produce their own value sheets or moral…

Stimulation of Cortical Myosin Phosphorylation by p114RhoGEF Drives Cell Migration and Tumor Cell Invasion

PubMed Central

Zihni, Ceniz; Harris, Andrew R.; Bailly, Maryse; Charras, Guillaume T.; Balda, Maria S.; Matter, Karl

2012-01-01

Actinomyosin activity is an important driver of cell locomotion and has been shown to promote collective cell migration of epithelial sheets as well as single cell migration and tumor cell invasion. However, the molecular mechanisms underlying activation of cortical myosin to stimulate single cell movement, and the relationship between the mechanisms that drive single cell locomotion and those that mediate collective cell migration of epithelial sheets are incompletely understood. Here, we demonstrate that p114RhoGEF, an activator of RhoA that associates with non-muscle myosin IIA, regulates collective cell migration of epithelial sheets and tumor cell invasion. Depletion of p114RhoGEF resulted in specific spatial inhibition of myosin activation at cell-cell contacts in migrating epithelial sheets and the cortex of migrating single cells, but only affected double and not single phosphorylation of myosin light chain. In agreement, overall elasticity and contractility of the cells, processes that rely on persistent and more constant forces, were not affected, suggesting that p114RhoGEF mediates process-specific myosin activation. Locomotion was p114RhoGEF-dependent on Matrigel, which favors more roundish cells and amoeboid-like actinomyosin-driven movement, but not on fibronectin, which stimulates flatter cells and lamellipodia-driven, mesenchymal-like migration. Accordingly, depletion of p114RhoGEF led to reduced RhoA, but increased Rac activity. Invasion of 3D matrices was p114RhoGEF-dependent under conditions that do not require metalloproteinase activity, supporting a role of p114RhoGEF in myosin-dependent, amoeboid-like locomotion. Our data demonstrate that p114RhoGEF drives cortical myosin activation by stimulating myosin light chain double phosphorylation and, thereby, collective cell migration of epithelial sheets and amoeboid-like motility of tumor cells. PMID:23185572

Horizontal electromagnetic casting of thin metal sheets

DOEpatents

Hull, John R.; Lari, Robert J.; Praeg, Walter F.; Turner, Larry R.

1987-01-01

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Horizontal electromagnetic casting of thin metal sheets

DOEpatents

Hull, John R.; Lari, Robert J.; Praeg, Walter F.; Turner, Larry R.

1988-01-01

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Method for heating a glass sheet

DOEpatents

Boaz, Premakaran Tucker

1998-01-01

A method for heating a glass sheet includes the steps of heating a glass sheet to a first predetermined temperature and applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature to allow the glass sheet to be formed.

Repair Mechanism of Osteochondral Defect Promoted by Bioengineered Chondrocyte Sheet

PubMed Central

Kamei, Naosuke; Adachi, Nobuo; Hamanishi, Michio; Kamei, Goki; Mahmoud, Elhussein Elbadry; Nakano, Tomohiro; Iwata, Takanori; Yamato, Masayuki; Okano, Teruo; Ochi, Mitsuo

2015-01-01

Cell sheet engineering has developed as a remarkable method for cell transplantation. In the field of cartilage regeneration, several studies previously reported that cartilage defects could be regenerated by transplantation of a chondrocyte sheet using cell sheet engineering. However, it remains unclear how such a thin cell sheet could repair a deep cartilage defect. We, therefore, focused on the mechanism of cartilage repair using cell sheet engineering in this study. Chondrocyte sheets and synovial cell sheets were fabricated using cell sheet engineering, and these allogenic cell sheets were transplanted to cover an osteochondral defect in a rat model. Macroscopic and histological evaluation was performed at 4 and 12 weeks after transplantation. Analysis of the gene expression of each cell sheet and of the regenerated tissue at 1 week after transplantation was performed. In addition, green fluorescent protein (GFP) transgenic rats were used as donors (transplanted chondrocyte sheets) or recipients (osteochondral defect models) to identify the cell origin of regenerated cartilage. Cartilage repair was significantly better in the group implanted with a chondrocyte sheet than in that with a synovial cell sheet. The results of gene expression analysis suggest that the possible factor contributing to cartilage repair might be TGFβ1. Cell tracking experiments using GFP transgenic rats showed that the regenerated cartilage was largely composed of cells derived from the transplanted chondrocyte sheets. PMID:25396711

Structurally Oriented Nano-Sheets in Co Thin Films: Changing Their Anisotropic Physical Properties by Thermally-Induced Relaxation

PubMed Central

Vergara, José; Favieres, Cristina; Magén, César; de Teresa, José María; Ibarra, Manuel Ricardo

2017-01-01

We show how nanocrystalline Co films formed by separated oblique nano-sheets display anisotropy in their resistivity, magnetization process, surface nano-morphology and optical transmission. After performing a heat treatment at 270 °C, these anisotropies decrease. This loss has been monitored measuring the resistivity as a function of temperature. The resistivity measured parallel to the direction of the nano-sheets has been constant up to 270 °C, but it decreases when measured perpendicular to the nano-sheets. This suggests the existence of a structural relaxation, which produces the change of the Co nano-sheets during annealing. The changes in the nano-morphology and the local chemical composition of the films at the nanoscale after heating above 270 °C have been analysed by scanning transmission electron microscopy (STEM). Thus, an approach and coalescence of the nano-sheets have been directly visualized. The spectrum of activation energies of this structural relaxation has indicated that the coalescence of the nano-sheets has taken place between 1.2 and 1.7 eV. In addition, an increase in the size of the nano-crystals has occurred in the samples annealed at 400 °C. This study may be relevant for the application in devices working, for example, in the GHz range and to achieve the retention of the anisotropy of these films at higher temperatures. PMID:29206155

Structurally Oriented Nano-Sheets in Co Thin Films: Changing Their Anisotropic Physical Properties by Thermally-Induced Relaxation.

PubMed

Vergara, José; Favieres, Cristina; Magén, César; de Teresa, José María; Ibarra, Manuel Ricardo; Madurga, Vicente

2017-12-05

We show how nanocrystalline Co films formed by separated oblique nano-sheets display anisotropy in their resistivity, magnetization process, surface nano-morphology and optical transmission. After performing a heat treatment at 270 °C, these anisotropies decrease. This loss has been monitored measuring the resistivity as a function of temperature. The resistivity measured parallel to the direction of the nano-sheets has been constant up to 270 °C, but it decreases when measured perpendicular to the nano-sheets. This suggests the existence of a structural relaxation, which produces the change of the Co nano-sheets during annealing. The changes in the nano-morphology and the local chemical composition of the films at the nanoscale after heating above 270 °C have been analysed by scanning transmission electron microscopy (STEM). Thus, an approach and coalescence of the nano-sheets have been directly visualized. The spectrum of activation energies of this structural relaxation has indicated that the coalescence of the nano-sheets has taken place between 1.2 and 1.7 eV. In addition, an increase in the size of the nano-crystals has occurred in the samples annealed at 400 °C. This study may be relevant for the application in devices working, for example, in the GHz range and to achieve the retention of the anisotropy of these films at higher temperatures.

A Synthesis of the Basal Thermal State of the Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Macgregor, J. A.; Fahnestock, M. A.; Catania, G. A.; Aschwanden, A.; Clow, G. D.; Colgan, W. T.; Gogineni, S. P.; Morlighem, M.; Nowicki, S. M. J.; Paden, J. D.;

Dynamic behaviour of the East Antarctic ice sheet during Pliocene warmth

NASA Astrophysics Data System (ADS)

Cook, Carys P.; van de Flierdt, Tina; Williams, Trevor; Hemming, Sidney R.; Iwai, Masao; Kobayashi, Munemasa; Jimenez-Espejo, Francisco J.; Escutia, Carlota; González, Jhon Jairo; Khim, Boo-Keun; McKay, Robert M.; Passchier, Sandra; Bohaty, Steven M.; Riesselman, Christina R.; Tauxe, Lisa; Sugisaki, Saiko; Galindo, Alberto Lopez; Patterson, Molly O.; Sangiorgi, Francesca; Pierce, Elizabeth L.; Brinkhuis, Henk; Klaus, Adam; Fehr, Annick; Bendle, James A. P.; Bijl, Peter K.; Carr, Stephanie A.; Dunbar, Robert B.; Flores, José Abel; Hayden, Travis G.; Katsuki, Kota; Kong, Gee Soo; Nakai, Mutsumi; Olney, Matthew P.; Pekar, Stephen F.; Pross, Jörg; Röhl, Ursula; Sakai, Toyosaburo; Shrivastava, Prakash K.; Stickley, Catherine E.; Tuo, Shouting; Welsh, Kevin; Yamane, Masako

2013-09-01

Warm intervals within the Pliocene epoch (5.33-2.58 million years ago) were characterized by global temperatures comparable to those predicted for the end of this century and atmospheric CO2 concentrations similar to today. Estimates for global sea level highstands during these times imply possible retreat of the East Antarctic ice sheet, but ice-proximal evidence from the Antarctic margin is scarce. Here we present new data from Pliocene marine sediments recovered offshore of Adélie Land, East Antarctica, that reveal dynamic behaviour of the East Antarctic ice sheet in the vicinity of the low-lying Wilkes Subglacial Basin during times of past climatic warmth. Sedimentary sequences deposited between 5.3 and 3.3 million years ago indicate increases in Southern Ocean surface water productivity, associated with elevated circum-Antarctic temperatures. The geochemical provenance of detrital material deposited during these warm intervals suggests active erosion of continental bedrock from within the Wilkes Subglacial Basin, an area today buried beneath the East Antarctic ice sheet. We interpret this erosion to be associated with retreat of the ice sheet margin several hundreds of kilometres inland and conclude that the East Antarctic ice sheet was sensitive to climatic warmth during the Pliocene.

Primary Astronomy.

ERIC Educational Resources Information Center

Greenstone, Sid; Smith, Murray

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics…

Astronomy.

ERIC Educational Resources Information Center

Greenstone, Sid; Smith, Murray

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics…

Intermediate Astronomy.

ERIC Educational Resources Information Center

Greenstone, Sid; Smith, Murray

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics…

78 FR 25699 - Foreign-Trade Zone (FTZ) 265-Conroe, Texas; Notification of Proposed Production Activity; Bauer...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-02

... foreign status components used in export production. On its domestic sales, Bauer would be able to choose... bands, plates, sheets, strips, bands), paper sheets/dials/rolls, articles of steel (shapes; U, H and I...

Method for heating a glass sheet

DOEpatents

Boaz, P.T.

1998-07-21

A method for heating a glass sheet includes the steps of heating a glass sheet to a first predetermined temperature and applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature to allow the glass sheet to be formed. 5 figs.

Method for heating and forming a glass sheet

DOEpatents

Boaz, Premakaran Tucker

1997-01-01

A method for heating and forming a glass sheet includes the steps of heating a glass sheet to at least a first predetermined temperature, applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature, cooling an outer surface of the glass sheet to at least a third predetermined temperature and forming the glass sheet using forming rollers to a predetermined configuration.

Wave-induced drift of large floating sheets

NASA Astrophysics Data System (ADS)

Christensen, K. H.; Weber, J. E.

In this article we study the wave-induced drift of large, flexible shallow floating objects, referred to as sheets. When surface waves propagate through a sheet, they provide a mean stress on the sheet, resulting in a mean drift. In response, the sheet generates an Ekman current. The drift velocity of the sheet is determined by (i) the wave-induced stress, (ii) the viscous stress due to the Ekman current, and (iii) the Coriolis force. The sheet velocity and the current beneath the sheet are determined for constant and depth-varying eddy viscosities.

FDTD modeling of thin impedance sheets

NASA Technical Reports Server (NTRS)

Luebbers, Raymond; Kunz, Karl

1991-01-01

Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. It is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods. These sheets are characterized by a discontinuity in the tangential magnetic field on either side of the sheet but no discontinuity in tangential electric field. This continuity, or single valued behavior of the electric field, allows the sheet current to be expressed in terms of an impedance multiplying this electric field.

Self-Pierce Riveting of Three Aluminium Alloy and Mild Steel Sheets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mori, K.; Abe, Y.; Sakai, S.

2010-06-15

Three aluminium alloy and steel sheets were joined with a self-piercing rivet. Self-pierce riveting has the function of joining steel and aluminium alloys having very different melting points due to plastic joining. The requisites for joining the three sheets are the driving of the rivet leg through the middle sheet, the flaring of the rivet leg in the lower sheet and the prevention of the fracture of the lower sheet. The joinability for various combinations of the three sheets was determined. When the rivet leg is small, no driving through the middle sheet occurs, the lower sheet ruptures for amore » large rivet leg. In addition, 980 MPa high strength steel, mild steel and aluminium alloy sheets were joined by the self-pierce riveting.« less

Collisionless current sheet equilibria

NASA Astrophysics Data System (ADS)

Neukirch, T.; Wilson, F.; Allanson, O.

2018-01-01

Current sheets are important for the structure and dynamics of many plasma systems. In space and astrophysical plasmas they play a crucial role in activity processes, for example by facilitating the release of magnetic energy via processes such as magnetic reconnection. In this contribution we will focus on collisionless plasma systems. A sensible first step in any investigation of physical processes involving current sheets is to find appropriate equilibrium solutions. The theory of collisionless plasma equilibria is well established, but over the past few years there has been a renewed interest in finding equilibrium distribution functions for collisionless current sheets with particular properties, for example for cases where the current density is parallel to the magnetic field (force-free current sheets). This interest is due to a combination of scientific curiosity and potential applications to space and astrophysical plasmas. In this paper we will give an overview of some of the recent developments, discuss their potential applications and address a number of open questions.

Properties of Rolled AZ31 Magnesium Alloy Sheet Fabricated by Continuous Variable Cross-Section Direct Extrusion

NASA Astrophysics Data System (ADS)

Liu, Yang; Li, Feng; Li, Xue Wen; Shi, Wen Yong

2018-03-01

Rolling is currently a widely used method for manufacturing and processing high-performance magnesium alloy sheets and has received widespread attention in recent years. Here, we combined continuous variable cross-section direct extrusion (CVCDE) and rolling processes. The microstructure and mechanical properties of the resulting sheets rolled at different temperatures from CVCDE extrudate were investigated by optical microscopy, scanning electron microscope, transmission electron microscopy and electron backscatter diffraction. The results showed that a fine-grained microstructure was present with an average grain size of 3.62 μm in sheets rolled from CVCDE extrudate at 623 K. Dynamic recrystallization and a large strain were induced by the multi-pass rolling, which resulted in grain refinement. In the 573-673 K range, the yield strength, tensile strength and elongation initially increased and then declined as the CVCDE temperature increased. The above results provide an important scientific basis of processing, manufacturing and the active control on microstructure and property for high-performance magnesium alloy sheet.

Interactive Ice Sheet Flowline Model for High School and College Students

NASA Astrophysics Data System (ADS)

Stearns, L. A.; Rezvanbehbahani, S.; Shankar, S.

2017-12-01

Teaching about climate and climate change is conceptually challenging. While teaching tools and lesson plans are rapidly evolving to help teachers and students improve their understanding of climate processes, there are very few tools targeting ice sheet and glacier dynamics. We have built an interactive ice sheet model that allows students to explore how Antarctic glaciers respond to different climate perturbations. Interactive models offer advantages that are hard to obtain in traditional classroom settings; users can systematically investigate hypothetical situations, explore the effects of modifying systems, and repeatedly observe how systems interrelate. As a result, this project provides a much-needed bridge between the data and models used by the scientific community and students in high school and college. We target our instructional and assessment activities to three high school and college students with the overall aim of increasing understanding of ice sheet dynamics and the different ways that ice sheets are impacted by climate change, while also improving their fundamental math skills.

Method for heating and forming a glass sheet

DOEpatents

Boaz, P.T.

1997-08-12

A method for heating and forming a glass sheet includes the steps of heating a glass sheet to at least a first predetermined temperature, applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature, cooling an outer surface of the glass sheet to at least a third predetermined temperature and forming the glass sheet using forming rollers to a predetermined configuration. 5 figs.

Junior High Astronomy.

ERIC Educational Resources Information Center

Greenstone, Sid; Smith, Murray

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics…

Practical Business: Instructor/Student Guide.

ERIC Educational Resources Information Center

Napier, Deedee Stocker

Ten units on practical business are presented in this instructor and student guide. Each instructional unit contains objectives, suggested activities, information sheets, assignment sheets, transparency master, a test, and test answers. Unit topics are (1) before you buy (comparative shopping and wise purchasing techniques); (2) when things go…

International Energy Agency (IEA): Implementing Agreement for Co-operation in the Research and Development of Wind Turbine Systems (IEA Wind)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinclair, Karin C

This fact sheet covers the work that is being done via the International Energy Agency Task 34 (WREN). The fact sheet highlights the objective, strategy, primary activities, members, and contacts for this task.

Nonadiabatic heating of the central plasma sheet at substorm onset

NASA Technical Reports Server (NTRS)

Huang, C. Y.; Frank, L. A.; Rostoker, G.; Fennell, J.; Mitchell, D. G.

1992-01-01

Heating events in the plasma sheet boundary layer and central plasma sheet are found to occur at the onset of expansive phase activity. The main effect is a dramatic increase in plasma temperature, coincident with a partial dipolarization of the magnetic field. Fluxes of energetic particles increase without dispersion during these events which occur at all radial distances up to 23 RE, the apogee of the ISEE spacecraft. A major difference between these heating events and those observed at geosynchronous distances lies in the heating mechanism which is nonadiabatic beyond 10 RE but may be adiabatic closer to earth. The energy required to account for the increase in plasma thermal energy is comparable with that required for Joule heating of the ionosphere. The plasma sheet must be considered as a major sink in the energy balance of a substorm. Lobe magnetic pressures during these events are estimated. Change in lobe pressure are generally not correlated with onsets or intensifications of expansive phase activity.

Electrode material comprising graphene-composite materials in a graphite network

DOEpatents

Kung, Harold H.; Lee, Jung K.

2014-07-15

A durable electrode material suitable for use in Li ion batteries is provided. The material is comprised of a continuous network of graphite regions integrated with, and in good electrical contact with a composite comprising graphene sheets and an electrically active material, such as silicon, wherein the electrically active material is dispersed between, and supported by, the graphene sheets.

Someday I May Want to Know about...Leisure and Recreational Activities for Children and Adults with Mental Retardation. A MCARC Information Sheet.

ERIC Educational Resources Information Center

Montgomery County Association for Retarded Citizens, Rockville, MD.

The fact sheet considers the importance of recreation and leisure time activities for people with mental retardation. A case is made for mainstreamed services, and suggestions are offered for families seeking to procure successful mainstreamed experiences in community recreational programs. Among suggestions are adapting family games to the…

Are Adolescents Talking with Their Parents about Sex before Becoming Sexually Active? Fact Sheet

ERIC Educational Resources Information Center

Leuschner, Kristin

2010-01-01

This paper examines parent-child discussions of sexual behavior. It finds consistency in the timing and content of such discussions; however, many parents and children do not discuss key topics, such as birth control, before adolescents become sexually active. [This fact sheet is based on Megan K. Beckett, Marc N. Elliott, Steven Martino, David E.…

Electrode material comprising graphene-composite materials in a graphite network

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kung, Harold H.; Lee, Jung K.

A durable electrode material suitable for use in Li ion batteries is provided. The material is comprised of a continuous network of graphite regions integrated with, and in good electrical contact with a composite comprising graphene sheets and an electrically active material, such as silicon, wherein the electrically active material is dispersed between, and supported by, the graphene sheets.

System for harvesting water wave energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhong Lin; Su, Yanjie; Zhu, Guang

A generator for harvesting energy from water in motion includes a sheet of a hydrophobic material, having a first side and an opposite second side, that is triboelectrically more negative than water. A first electrode sheet is disposed on the second side of the sheet of a hydrophobic material. A second electrode sheet is disposed on the second side of the sheet of a hydrophobic material and is spaced apart from the first electrode sheet. Movement of the water across the first side induces an electrical potential imbalance between the first electrode sheet and the second electrode sheet.

Investigation of the magnetic properties of Si-gradient steel sheet by comparison with 6.5%Si steel sheet

NASA Astrophysics Data System (ADS)

Hiratani, T.; Zaizen, Y.; Oda, Y.; Yoshizaki, S.; Senda, K.

2018-05-01

In this study, we investigated the magnetic properties of Si-gradient steel sheet produced by CVD (chemical vapor deposition) siliconizing process, comparing with 6.5% Si steel sheet. The Si-gradient steel sheet having silicon concentration gradient in the thickness direction, has larger hysteresis loss and smaller eddy current loss than the 6.5% Si steel sheet. In such a loss configuration, the iron loss of the Si-gradient steel sheet becomes lower than that of the 6.5% Si steel sheet at high frequencies. The experiment suggests that tensile stress is formed at the surface layer and compressive stress is formed at the inner layer in the Si gradient steel sheet. The magnetic anisotropy is induced by the internal stress and it is considered to affect the magnetization behavior of the Si-gradient steel sheet. The small eddy current loss of Si-gradient steel sheet can be explained as an effect of magnetic flux concentration on the surface layer.

Optimal swimming of a sheet.

PubMed

Montenegro-Johnson, Thomas D; Lauga, Eric

2014-06-01

Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

46 CFR 160.060-1 - Incorporation by reference.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-1: Sheet 1—Cutting Pattern and General Arrangement, Model AY. Sheet 2—Cutting Pattern and General Arrangement, Model CYM. Sheet 3—Cutting Pattern and General Arrangement, Model CYS. Sheet 4—Insert Pattern, Model AY. Sheet 5—Insert Pattern, Model CYM. Sheet 6—Insert Pattern, Model CYS. (c) Copies on file...

Fatigue Micromechanism Characterization in Carbon Fibre Reinforced Polymers Using Synchrotron Radiation Computed Tomography

DTIC Science & Technology

2014-12-18

Resources/DataSheets/ Prepreg -Data- Sheets/M21_global.pdf. [20] Hexcel HexPly 8552. http://www.hexcel.com/Resources/DataSheets/ Prepreg -Data- Sheets...8552_eu.pdf [21] 3501-6 Epoxy Matrix, Hexcel. http://www.hexcel.com/Resources/DataSheets/ Prepreg -Data- Sheets/3501-6_eu.pdf [22] B.A. Dowd, G.H

How might the North American ice sheet influence the northwestern Eurasian climate?

NASA Astrophysics Data System (ADS)

Beghin, P.; Charbit, S.; Dumas, C.; Kageyama, M.; Ritz, C.

2015-10-01

It is now widely acknowledged that past Northern Hemisphere ice sheets covering Canada and northern Europe at the Last Glacial Maximum (LGM) exerted a strong influence on climate by causing changes in atmospheric and oceanic circulations. In turn, these changes may have impacted the development of the ice sheets themselves through a combination of different feedback mechanisms. The present study is designed to investigate the potential impact of the North American ice sheet on the surface mass balance (SMB) of the Eurasian ice sheet driven by simulated changes in the past glacial atmospheric circulation. Using the LMDZ5 atmospheric circulation model, we carried out 12 experiments under constant LGM conditions for insolation, greenhouse gases and ocean. In these experiments, the Eurasian ice sheet is removed. The 12 experiments differ in the North American ice-sheet topography, ranging from a white and flat (present-day topography) ice sheet to a full-size LGM ice sheet. This experimental design allows the albedo and the topographic impacts of the North American ice sheet onto the climate to be disentangled. The results are compared to our baseline experiment where both the North American and the Eurasian ice sheets have been removed. In summer, the sole albedo effect of the American ice sheet modifies the pattern of planetary waves with respect to the no-ice-sheet case, resulting in a cooling of the northwestern Eurasian region. By contrast, the atmospheric circulation changes induced by the topography of the North American ice sheet lead to a strong decrease of this cooling. In winter, the Scandinavian and the Barents-Kara regions respond differently to the American ice-sheet albedo effect: in response to atmospheric circulation changes, Scandinavia becomes warmer and total precipitation is more abundant, whereas the Barents-Kara area becomes cooler with a decrease of convective processes, causing a decrease of total precipitation. The gradual increase of the altitude of the American ice sheet leads to less total precipitation and snowfall and to colder temperatures over both the Scandinavian and the Barents and Kara sea sectors. We then compute the resulting annual surface mass balance over the Fennoscandian region from the simulated temperature and precipitation fields used to force an ice-sheet model. It clearly appears that the SMB is dominated by the ablation signal. In response to the summer cooling induced by the American ice-sheet albedo, high positive SMB values are obtained over the Eurasian region, leading thus to the growth of an ice sheet. On the contrary, the gradual increase of the American ice-sheet altitude induces more ablation over the Eurasian sector, hence limiting the growth of Fennoscandia. To test the robustness of our results with respect to the Eurasian ice sheet state, we carried out two additional LMDZ experiments with new boundary conditions involving both the American (flat or full LGM) and high Eurasian ice sheets. The most striking result is that the Eurasian ice sheet is maintained under full-LGM North American ice-sheet conditions, but loses ~ 10 % of its mass compared to the case in which the North American ice sheet is flat. These new findings qualitatively confirm the conclusions from our first series of experiments and suggest that the development of the Eurasian ice sheet may have been slowed down by the growth of the American ice sheet, offering thereby a new understanding of the evolution of Northern Hemisphere ice sheets throughout glacial-interglacial cycles.

Geometry of thin liquid sheet flows

NASA Technical Reports Server (NTRS)

Chubb, Donald L.; Calfo, Frederick D.; Mcconley, Marc W.; Mcmaster, Matthew S.; Afjeh, Abdollah A.

1994-01-01

Incompresible, thin sheet flows have been of research interest for many years. Those studies were mainly concerned with the stability of the flow in a surrounding gas. Squire was the first to carry out a linear, invicid stability analysis of sheet flow in air and compare the results with experiment. Dombrowski and Fraser did an experimental study of the disintegration of sheet flows using several viscous liquids. They also detected the formulation of holes in their sheet flows. Hagerty and Shea carried out an inviscid stability analysis and calculated growth rates with experimental values. They compared their calculated growth rates with experimental values. Taylor studied extensively the stability of thin liquid sheets both theoretically and experimentally. He showed that thin sheets in a vacuum are stable. Brown experimentally investigated thin liquid sheet flows as a method of application of thin films. Clark and Dumbrowski carried out second-order stability analysis for invicid sheet flows. Lin introduced viscosity into the linear stability analysis of thin sheet flows in a vacuum. Mansour and Chigier conducted an experimental study of the breakup of a sheet flow surrounded by high-speed air. Lin et al. did a linear stability analysis that included viscosity and a surrounding gas. Rangel and Sirignano carried out both a linear and nonlinear invisid stability analysis that applies for any density ratio between the sheet liquid and the surrounding gas. Now there is renewed interest in sheet flows because of their possible application as low mass radiating surfaces. The objective of this study is to investigate the fluid dynamics of sheet flows that are of interest for a space radiator system. Analytical expressions that govern the sheet geometry are compared with experimental results. Since a space radiator will operate in a vacuum, the analysis does not include any drag force on the sheet flow.

Magma transport in sheet intrusions of the Alnö carbonatite complex, central Sweden.

PubMed

Andersson, Magnus; Almqvist, Bjarne S G; Burchardt, Steffi; Troll, Valentin R; Malehmir, Alireza; Snowball, Ian; Kübler, Lutz

2016-06-10

Magma transport through the Earth's crust occurs dominantly via sheet intrusions, such as dykes and cone-sheets, and is fundamental to crustal evolution, volcanic eruptions and geochemical element cycling. However, reliable methods to reconstruct flow direction in solidified sheet intrusions have proved elusive. Anisotropy of magnetic susceptibility (AMS) in magmatic sheets is often interpreted as primary magma flow, but magnetic fabrics can be modified by post-emplacement processes, making interpretation of AMS data ambiguous. Here we present AMS data from cone-sheets in the Alnö carbonatite complex, central Sweden. We discuss six scenarios of syn- and post-emplacement processes that can modify AMS fabrics and offer a conceptual framework for systematic interpretation of magma movements in sheet intrusions. The AMS fabrics in the Alnö cone-sheets are dominantly oblate with magnetic foliations parallel to sheet orientations. These fabrics may result from primary lateral flow or from sheet closure at the terminal stage of magma transport. As the cone-sheets are discontinuous along their strike direction, sheet closure is the most probable process to explain the observed AMS fabrics. We argue that these fabrics may be common to cone-sheets and an integrated geology, petrology and AMS approach can be used to distinguish them from primary flow fabrics.

Magma transport in sheet intrusions of the Alnö carbonatite complex, central Sweden

PubMed Central

Andersson, Magnus; Almqvist, Bjarne S. G.; Burchardt, Steffi; Troll, Valentin R.; Malehmir, Alireza; Snowball, Ian; Kübler, Lutz

2016-01-01

Magma transport through the Earth’s crust occurs dominantly via sheet intrusions, such as dykes and cone-sheets, and is fundamental to crustal evolution, volcanic eruptions and geochemical element cycling. However, reliable methods to reconstruct flow direction in solidified sheet intrusions have proved elusive. Anisotropy of magnetic susceptibility (AMS) in magmatic sheets is often interpreted as primary magma flow, but magnetic fabrics can be modified by post-emplacement processes, making interpretation of AMS data ambiguous. Here we present AMS data from cone-sheets in the Alnö carbonatite complex, central Sweden. We discuss six scenarios of syn- and post-emplacement processes that can modify AMS fabrics and offer a conceptual framework for systematic interpretation of magma movements in sheet intrusions. The AMS fabrics in the Alnö cone-sheets are dominantly oblate with magnetic foliations parallel to sheet orientations. These fabrics may result from primary lateral flow or from sheet closure at the terminal stage of magma transport. As the cone-sheets are discontinuous along their strike direction, sheet closure is the most probable process to explain the observed AMS fabrics. We argue that these fabrics may be common to cone-sheets and an integrated geology, petrology and AMS approach can be used to distinguish them from primary flow fabrics. PMID:27282420

The microbiome of glaciers and ice sheets.

PubMed

Anesio, Alexandre M; Lutz, Stefanie; Chrismas, Nathan A M; Benning, Liane G

2017-01-01

Glaciers and ice sheets, like other biomes, occupy a significant area of the planet and harbour biological communities with distinct interactions and feedbacks with their physical and chemical environment. In the case of the glacial biome, the biological processes are dominated almost exclusively by microbial communities. Habitats on glaciers and ice sheets with enough liquid water to sustain microbial activity include snow, surface ice, cryoconite holes, englacial systems and the interface between ice and overridden rock/soil. There is a remarkable similarity between the different specific glacial habitats across glaciers and ice sheets worldwide, particularly regarding their main primary producers and ecosystem engineers. At the surface, cyanobacteria dominate the carbon production in aquatic/sediment systems such as cryoconite holes, while eukaryotic Zygnematales and Chlamydomonadales dominate ice surfaces and snow dynamics, respectively. Microbially driven chemolithotrophic processes associated with sulphur and iron cycle and C transformations in subglacial ecosystems provide the basis for chemical transformations at the rock interface under the ice that underpin an important mechanism for the delivery of nutrients to downstream ecosystems. In this review, we focus on the main ecosystem engineers of glaciers and ice sheets and how they interact with their chemical and physical environment. We then discuss the implications of this microbial activity on the icy microbiome to the biogeochemistry of downstream ecosystems.

The effect of the coumarin-like derivative osthole on the osteogenic properties of human periodontal ligament and jaw bone marrow mesenchymal stem cell sheets.

PubMed

Gao, Li-Na; An, Ying; Lei, Ming; Li, Bei; Yang, Hao; Lu, Hong; Chen, Fa-Ming; Jin, Yan

2013-12-01

Cell sheet engineering is a scaffold-free delivery concept that has been shown to improve mesenchymal stem cell-mediated regeneration of injured or pathologically damaged periodontal tissues in preclinical studies and several clinical trials. However, the best strategy for cell sheet production remains to be identified. The aim of this study was to investigate the biological effects of osthole, a coumarin-like derivative extracted from Chinese herbs, on the cell sheet formation and osteogenic properties of human periodontal ligament stem cells (PDLSCs) and jaw bone marrow mesenchymal stem cells (JBMMSCs). Patient-matched PDLSCs and JBMMSCs were isolated, and an appropriate concentration of osthole for cell culture was screened for both cell types in terms of cell proliferation and alkaline phosphatase (ALP) activity. Next, the best mode of osthole stimulation for inducing the formation of sheets by each cell type was selected by evaluating the amount of their extracellular matrix (ECM) protein production as well as osteogenic-related gene expression. Furthermore, both PDLSC and JBMMSC sheets obtained from each optimized technique were transplanted subcutaneously into nude mice to evaluate their capacity for ectopic bone regeneration. The results revealed that 10(-5) m/L osthole significantly enhanced the proliferation of both PDLSCs and JBMMSCs (P < 0.05), although for JBMMSCs, there was no concentration-related change among the four established osthole groups (P > 0.05). In addition, 10(-5) m/L osthole was the best concentration to promote the ALP activities of both cells (P < 0.01). Based on both the production of ECM proteins (collagen type I, integrin β1, and fibronectin) and the expression of osteogenic genes (ALP, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)), the provision of 10(-5) m/L osthole throughout the entire culture stage (10 days) for PDLSCs or at the early stage (first 3 days) for JBMMSCs was the most effective osthole administration mode for cell sheet formation (P < 0.05). The results of in vivo transplantation showed that osthole-mediated PDLSC and JBMMSC sheets formed more new bone than those obtained without osthole intervention (P < 0.001). Our data suggest that a suitable concentration and mode of osthole stimulation may enhance ECM production and positively affect cell behavior in cell sheet engineering. Copyright © 2013 Elsevier Ltd. All rights reserved.

A web-based fact sheet series for grandparents raising grandchildren and the professionals who serve them.

PubMed

Brintnall-Peterson, Mary; Poehlmann, Julie; Morgan, Kari; Shlafer, Rebecca

2009-04-01

To develop and evaluate a series of web-based fact sheets for grandparents raising grandchildren. The fact sheets focus on child development issues that grandparents may face when raising their grandchildren. The fact sheets were developed using research on attachment theory, child development, and the needs of grandparents raising grandchildren. The fact sheets can be viewed online or downloaded for free. Evaluation data for the fact sheets were gathered using an online survey. Results of the survey revealed that the fact sheets are used by grandparents and professionals. Respondents reported sharing the fact sheets with others and using them for personal use, in support groups, and as a general agency resource. The fact sheet series is a useful way to reach both grandparents and professionals working with this audience in a variety of settings. Modifications to the fact sheet series are suggested to address additional needs of grandparents raising grandchildren.

Solid oxide fuel cell with multi-unit construction and prismatic design

DOEpatents

McPheeters, Charles C.; Dees, Dennis W.; Myles, Kevin M.

1999-01-01

A single cell unit of a solid oxide fuel cell that is individually fabricated and sintered prior to being connected to adjacent cells to form a solid oxide fuel cell. The single cell unit is comprised of a shaped anode sheet positioned between a flat anode sheet and an anode-electrolyte-cathode (A/E/C) sheet, and a shaped cathode sheet positioned between the A/E/C sheet and a cathode-interconnect-anode (C/I/A) sheet. An alternate embodiment comprises a shaped cathode sheet positioned between an A/E/C sheet and a C/I/A sheet. The shaped sheets form channels for conducting reactant gases. Each single cell unit is individually sintered to form a finished sub-assembly. The finished sub-assemblies are connected in electrical series by interposing connective material between the end surfaces of adjacent cells, whereby individual cells may be inspected for defects and interchanged with non-defective single cell units.

Featuring: It Works! Competency Based Instruction.

ERIC Educational Resources Information Center

Elston, Teri

1979-01-01

Describes a competency based curriculum approach for ornamental horticulture. A horticulture cluster core consisting of 18 tasks was developed with competency sheets for each task. The competency sheet contains six columns: skills to be attained, task list, materials required, student activities, evaluation methods, and a recommended time period.…

Scaling results for the liquid sheet radiator

NASA Technical Reports Server (NTRS)

Chubb, Donald L.; Calfo, Frederick D.

1989-01-01

Surface tension forces at the edges of a thin liquid (approx 100 micrometers) sheet flow result in a triangularly shaped sheet. Such a geometry is ideal for an external flow radiator. The experimental investigation of such sheet flows was extended to large sheets (width = 23.5 cm, length = 3.5 m). Experimental L/W results are greater than the calculated results. However, more experimental results are necessary for a complete comparison. The calculated emissivity of a sheet of Dow-Corning 705 silicone oil, which is low temperature (300-400 K) candidate for a liquid sheet radiator (LSR), is greater than 0.8 for sheet thicknesses greater than 100 micrometers.

SU-F-T-550: Radiochromic Plastic Thin Sheet Dosimeter: Initial Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jordan, K; Adamovics, J

Purpose: Thin sheets, of a high sensitivity formulation of radiochromic dosimeter, Presage were prepared and evaluated for optical readout. Methods: Sheets of radiochromic polyurethane, 12 cm long, 10 cm wide and 0.2 cm thick were prepared with leuco crystal violet as the reporter molecule. Sample transmission was evaluated at a wavelength of 590 nm with in-house constructed instruments: optical cone beam laser CT scanner, fixed and scanning spot densitometers. Sample sequential irradiations to a total dose of 40 Gy were conducted with a modified, Theratron 60, cobalt radiotherapy machine at dose rates of 1 or 0.25 Gy per minute. Exposuremore » to ambient and readout light was minimized to limit background photochromic signals. Samples were stored at 4°C. Optical activity was assessed from linearly polarized transmission images. Comparison sensitivity measurements with EBT3 film were conducted. Results: Samples were transparent, smooth and pale purple before irradiation. Radiochromic reaction was completed in less than 5 minutes. A linear dose response with a sensitivity of 0.5 cm-1Gy-1 was observed. Micrometer measurements found sheet thickness variations up to 20%. Uniform dose, 2 Gy attenuation images, correlated with local sheet thicknesses. Comparable measurements with EBT3 film were 3 times more sensitive at 1 Gy but above 15 Gy, EBT3 film had lower sensitivity than 0.2 cm thick Presage sheet dosimeter due to its non-linear response. Conclusion: Dose sensitivity provided a 10% decrease in transmission for a 1 Gy dose. Improvements in mold design are expected to allow production of sheets with less than 5% variation in thickness. Above, 10 Gy, Presage sheet dosimeter performance expected to exceed EBT3 film based on linearity, sensitivity, transparency and smoothness of samples. J Adamovics is owner of Heuris Inc.« less

Plasma sheet dynamics observed by the Polar spacecraft in association with substorm onsets

NASA Astrophysics Data System (ADS)

Toivanen, P. K.; Baker, D. N.; Peterson, W. K.; Li, X.; Donovan, E. F.; Viljanen, A.; Keiling, A.; Wygant, J. R.; Kletzing, C. A.

2001-09-01

We present observations of the Polar spacecraft of magnetospheric substorm signatures in the plasma sheet midway along auroral field lines between the ionosphere and the equatorial plasma sheet. On October 17, 1997, Polar was located in the onset meridian in conjunction with the Scandinavian magnetometer chain (International Monitor for Auroral Geomagnetic Effects; IMAGE). In addition, a geostationary spacecraft, LANL-97A, was located near the onset meridian. On August 29, 1997, Polar was magnetically conjugate to the Canadian magnetometer chain (Canadian Auroral Network for the OPEN Program Unified Study; CANOPUS) ~5 hours east of the onset meridian. In both cases, substorm activity was manifested as strong magnetic (20 nT) and electric (40 mVm-1) field variations with bursts of parallel Poynting flux (~1 ergcm-2s-1), predominantly directed toward the ionosphere. In the first event Polar was located in the plasma sheet near the plasma sheet boundary, and the field variations were initiated at the ground onset. In the second event, Polar crossed the plasma sheet boundary to the tail lobes a few minutes prior to a local plasma sheet expansion. As Polar was engulfed by the plasma sheet, the field variations occurred in the previously quiet plasma sheet boundary. This coincided with the auroral bulge reaching the CANOPUS stations. We compare these two events and argue that the field variations were most probably signatures of the reconnection of open field lines and the subsequent enhanced earthward flows. Furthermore, weak flow bursts were observed at Polar in both events ~9 min before the onset. In the first event, a gradual development toward a negative bay and a burst of Pi2 pulsations were associated with the flow bursts. We anticipate that these signatures, often described in terms of pseudobreakups, were a precursor of the substorm onset, the initiation of the reconnection of closed field lines.

Experimental investigation of a 1 kA/cm² sheet beam plasma cathode electron gun.

PubMed

Kumar, Niraj; Pal, Udit Narayan; Pal, Dharmendra Kumar; Prajesh, Rahul; Prakash, Ram

2015-01-01

In this paper, a cold cathode based sheet-beam plasma cathode electron gun is reported with achieved sheet-beam current density ∼1 kA/cm(2) from pseudospark based argon plasma for pulse length of ∼200 ns in a single shot experiment. For the qualitative assessment of the sheet-beam, an arrangement of three isolated metallic-sheets is proposed. The actual shape and size of the sheet-electron-beam are obtained through a non-conventional method by proposing a dielectric charging technique and scanning electron microscope based imaging. As distinct from the earlier developed sheet beam sources, the generated sheet-beam has been propagated more than 190 mm distance in a drift space region maintaining sheet structure without assistance of any external magnetic field.

Dual modes of motility at the leading edge of migrating epithelial cell sheets

PubMed Central

Klarlund, Jes K.

2012-01-01

Purse-string healing is driven by contraction of actin/myosin cables that span cells at wound edges, and it is the predominant mode of closing small round wounds in embryonic and some adult epithelia. Wounds can also heal by cell crawling, and my colleagues and I have shown previously that the presence of unconstrained, straight edges in sheets of epithelial cells is a sufficient signal to induce healing by crawling. Here, it is reported that the presence of highly concave edges, which are free or physically constrained by an inert material (agarose), is sufficient to induce formation of purse strings. It was determined that neither of the two types of healing required cell damage or other potential stimuli by using the particularly gentle procedure of introducing gaps by digesting agarose blocks imbedded in the cell sheets. Movement by crawling depends on signaling by the EGF receptor (EGFR); however, this was not required for purse-string contraction. A migrating epithelial cell sheet usually produces finger-like projections of crawling cells. The cells between fingers contain continuous actin cables, which were also determined to contain myosin IIA and exhibit additional characteristics of purse strings. When crawling was blocked by inhibition of EGFR signaling, the concave regions continued to move, suggesting that both mechanisms contribute to propel the sheets forward. Wounding epithelial cell sheets causes activation of the EGFR, which triggers movement by crawling. The EGFR was found to be activated only at straight and convex edges, which explains how both types of movement can coexist at leading epithelial edges. PMID:23019364

"The Very First Family": A Musical Play by Philip Hall, Based on Stories by Rudyard Kipling. Cue Sheet for Teachers.

ERIC Educational Resources Information Center

Flynn, Rosalind

Designed to be used before and after attending a performance of the musical play "The Very First Family" (in which a Stone Age family and their neighbors bring three of Rudyard Kipling's stories to life), this cue sheet for teachers presents information about the performance and suggests classroom activities. The activities in the cue…

Medical-Surgical II. Teacher Edition.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This publication is designed to provide students with the knowledge they need to pursue a career in medical-surgical nursing. Fifteen units are provided. Each instructional unit includes some or all of the basic components of a unit of instruction: performance objectives, suggested activities for the teacher, information sheets, job sheets,…

General Metal Trades Book I. Units of Instruction. Teacher's Guide.

ERIC Educational Resources Information Center

East Texas State Univ., Commerce. Occupational Curriculum Lab.

This teacher's guide provides instructional materials for a 10-unit course in the General Metal Trades program. Each unit includes most or all of these basic components: performance objectives (unit and specific objectives), suggested teaching activities (a sheet outlining steps to follow to accomplish specific objectives), information sheets,…

Transportation Systems. Curriculum Guide for Technology Education.

ERIC Educational Resources Information Center

Chastain, Gary K.

This curriculum guide for a 1-semester or 1-year course in transportation provides activities that show and explain many of the occupations, devices, and systems that are related to transportation on land, water, air, and space. The guide contains competencies (task lists), student competency records, and management sheets. Management sheets,…

Medical-Surgical I. Teacher Edition.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This publication is designed to provide students with the knowledge they need to pursue a career in medical-surgical nursing. Eight units are provided. Each instructional unit includes some or all of the basic components of a unit of instruction: performance objectives, suggested activities for the teacher, information sheets, job sheets, written…

75 FR 43995 - Agency Information Collection Activities: Submission for OMB Review; Comment Request, OMB No...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-27

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency [Docket ID: FEMA-2010-0026...; FEMA/EMI Independent Study Course Enrollment and Test Answer Sheet AGENCY: Federal Emergency Management... Course Enrollment and Test Answer Sheet (paper and electronic). SUMMARY: The Federal Emergency Management...

Periodontal regeneration with multi-layered periodontal ligament-derived cell sheets in a canine model.

PubMed

Iwata, Takanori; Yamato, Masayuki; Tsuchioka, Hiroaki; Takagi, Ryo; Mukobata, Shigeki; Washio, Kaoru; Okano, Teruo; Ishikawa, Isao

2009-05-01

Periodontal regeneration has been challenged with chemical reagents and/or biological approaches, however, there is still no sufficient technique that can regenerate complete periodontium, including alveolar bone, cementum, and well-oriented collagen fibers. The purpose of this study was to examine multi-layered sheets of periodontal ligament (PDL)-derived cells for periodontal regeneration. Canine PDL cells were isolated enzymatically and expanded in vitro. The cell population contained cells capable of making single cell-derived colonies at an approximately 20% frequency. Expression of mRNA of periodontal marker genes, S100 calcium binding protein A4 and periostin, was observed. Alkaline phosphatase activity and gene expression of both osteoblastic/cementoblastic and periodontal markers were upregulated by osteoinductive medium. Then, three-layered PDL cell sheets supported with woven polyglycolic acid were transplanted to dental root surfaces having three-wall periodontal defects in an autologous manner, and bone defects were filled with porous beta-tricalcium phosphate. Cell sheet transplantation regenerated both new bone and cementum connecting with well-oriented collagen fibers, while only limited bone regeneration was observed in control group where cell sheet transplantation was eliminated. These results suggest that PDL cells have multiple differentiation properties to regenerate periodontal tissues comprising hard and soft tissues. PDL cell sheet transplantation should prove useful for periodontal regeneration in clinical settings.

N-Isopropylacrylamide-co-glycidylmethacrylate as a Thermoresponsive Substrate for Corneal Endothelial Cell Sheet Engineering

PubMed Central

Madathil, Bernadette K.; Anil Kumar, Pallickaveedu RajanAsari; Kumary, Thrikkovil Variyath

2014-01-01

Endothelial keratoplasty is a recent shift in the surgical treatment of corneal endothelial dystrophies, where the dysfunctional endothelium is replaced whilst retaining the unaffected corneal layers. To overcome the limitation of donor corneal shortage, alternative use of tissue engineered constructs is being researched. Tissue constructs with intact extracellular matrix are generated using stimuli responsive polymers. In this study we evaluated the feasibility of using the thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate) polymer as a culture surface to harvest viable corneal endothelial cell sheets. Incubation below the lower critical solution temperature of the polymer allowed the detachment of the intact endothelial cell sheet. Phase contrast and scanning electron microscopy revealed the intact architecture, cobble stone morphology, and cell-to-cell contact in the retrieved cell sheet. Strong extracellular matrix deposition was also observed. The RT-PCR analysis confirmed functionally active endothelial cells in the cell sheet as evidenced by the positive expression of aquaporin 1, collagen IV, Na+-K+ ATPase, and FLK-1. Na+-K+ ATPase protein expression was also visualized by immunofluorescence staining. These results suggest that the in-house developed thermoresponsive culture dish is a suitable substrate for the generation of intact corneal endothelial cell sheet towards transplantation for endothelial keratoplasty. PMID:25003113

New directions in the science and technology of advanced sheet explosive formulations and the key energetic materials used in the processing of sheet explosives: Emerging trends.

PubMed

Talawar, M B; Jangid, S K; Nath, T; Sinha, R K; Asthana, S N

2015-12-30

This review presents the work carried out by the international community in the area of sheet explosive formulations and its applications in various systems. The sheet explosive is also named as PBXs and is a composite material in which solid explosive particles like RDX, HMX or PETN are dispersed in a polymeric matrix, forms a flexible material that can be rolled/cut into sheet form which can be applied to any complex contour. The designed sheet explosive must possess characteristic properties such as flexible, cuttable, water proof, easily initiable, and safe handling. The sheet explosives are being used for protecting tanks (ERA), light combat vehicle and futuristic infantry carrier vehicle from different attacking war heads etc. Besides, sheet explosives find wide applications in demolition of bridges, ships, cutting and metal cladding. This review also covers the aspects such as risks and hazard analysis during the processing of sheet explosive formulations, effect of ageing on sheet explosives, detection and analysis of sheet explosive ingredients and the R&D efforts of Indian researchers in the development of sheet explosive formulations. To the best of our knowledge, there has been no review article published in the literature in the area of sheet explosives. Copyright © 2015 Elsevier B.V. All rights reserved.

Magnetic Configurations of the Tilted Current Sheets and Dynamics of Their Flapping in Magnetotail

NASA Astrophysics Data System (ADS)

Shen, C.; Rong, Z. J.; Li, X.; Dunlop, M.; Liu, Z. X.; Malova, H. V.; Lucek, E.; Carr, C.

2009-04-01

Based on multiple spacecraft measurements, the geometrical structures of tilted current sheet and tail flapping waves have been analyzed and some features of the tilted current sheets have been made clear for the first time. The geometrical features of the tilted current sheet revealed in this investigation are as follows: (1) The magnetic field lines (MFLs) are generally plane curves and the osculating planes in which the MFLs lie are about vertical to the magnetic equatorial plane, while the tilted current sheet may lean severely to the dawn or dusk side. (2) The tilted current sheet may become very thin, its half thickness is generally much less than the minimum radius of the curvature of the MFLs. (3) In the neutral sheet, the field-aligned current density becomes very large and has a maximum value at the center of the current sheet. (4) In some cases, the current density is a bifurcated one, and the two humps of the current density often superpose two peaks in the gradient of magnetic strength, indicating that the magnetic gradient drift current is possibly responsible for the formation of the two humps of the current density in some tilted current sheets. Tilted current sheets often appear along with tail thick current sheet flapping waves. It is found that, in the tail flapping current sheets, the minimum curvature radius of the MFLs in the current sheet is rather large with values around 1RE, while the neutral sheet may be very thin, with its half thickness being several tenths ofRE. During the flapping waves, the current sheet is tilted substantially, and the maximum tilt angle is generally larger than 45

Emittance Measurements for a Thin Liquid Sheet Flow

NASA Technical Reports Server (NTRS)

Englehart, Amy N.; McConley, Marc W.; Chubb, Donald L.

1996-01-01

The Liquid Sheet Radiator (LSR) is an external flow radiator that uses a triangular-shaped flowing liquid sheet as the radiating surface. It has potentially much lower mass than solid wall radiators such as pumped loop and heat pipe radiators, along with being nearly immune to micrometeoroid penetration. The LSR has an added advantage of simplicity. Surface tension causes a thin (100-300 microns) liquid sheet to coalesce to a point, causing the sheet flow to have a triangular shape. Such a triangular sheet is desirable since it allows for simple collection of the flow at a single point. A major problem for all external flow radiators is the requirement that the working fluid be of very low (approx. 10(sup -8) torr) vapor pressure to keep evaporative losses low. As a result, working fluids are limited to certain oils (such as used in diffusion pumps) for low temperatures (300-400 K) and liquid metals for higher temperatures. Previous research on the LSR has been directed at understanding the fluid mechanics of thin sheet flows and assessing the stability of such flows, especially with regard to the formation of holes in the sheet. Taylor studied extensively the stability of thin liquid sheets both theoretically and experimentally. He showed that thin sheets in a vacuum are stable. The latest research has been directed at determining the emittance of thin sheet flows. The emittance was calculated from spectral transmittance data for the Dow Corning 705 silicone oil. By experimentally setting up a sheet flow, the emittance was also determined as a function of measurable quantities, most importantly, the temperature drop between the top of the sheet and the temperature at the coalescence point of the sheet. Temperature fluctuations upstream of the liquid sheet were a potential problem in the analysis and were investigated.

Scaling results for the Liquid Sheet Radiator (LSR)

NASA Technical Reports Server (NTRS)

Chubb, Donald L.; Calfo, Frederick D.

1989-01-01

Surface tension forces at the edges of a thin liquid (approx. 100 micrometers) sheet flow result in a triangularly shaped sheet. Such a geometry is ideal for an external flow radiator. The experimental investigation of such sheet flows was extended to large sheets (width = W = 23.5 cm, length = L approx. = 3.5 m). Experimental L/W results are greater than the calculated results. However, more experimental results are necessary for a complete comparison. The calculated emissivity of a sheet of Dow-Corning 705 silicone oil, which is a low temperature (300 to 400K) candidate for a liquid sheet radiator (LSR), is greater than .8 for sheet thicknesses greater than 100 micrometers.

Methods for Using Durable Adhesively Bonded Joints for Sandwich Structures

NASA Technical Reports Server (NTRS)

Smeltzer, Stanley S., III (Inventor); Lundgren, Eric C. (Inventor)

2016-01-01

Systems, methods, and apparatus for increasing durability of adhesively bonded joints in a sandwich structure. Such systems, methods, and apparatus includes an first face sheet and an second face sheet as well as an insert structure, the insert structure having a first insert face sheet, a second insert face sheet, and an insert core material. In addition, sandwich core material is arranged between the first face sheet and the second face sheet. A primary bondline may be coupled to the face sheet(s) and the splice. Further, systems, methods, and apparatus of the present disclosure advantageously reduce the load, provide a redundant path, reduce structural fatigue, and/or increase fatigue life.

Buckling and stretching of thin viscous sheets

NASA Astrophysics Data System (ADS)

O'Kiely, Doireann; Breward, Chris; Griffiths, Ian; Howell, Peter; Lange, Ulrich

2016-11-01

Thin glass sheets are used in smartphone, battery and semiconductor technology, and may be manufactured by producing a relatively thick glass slab and subsequently redrawing it to a required thickness. The resulting sheets commonly possess undesired centerline ripples and thick edges. We present a mathematical model in which a viscous sheet undergoes redraw in the direction of gravity, and show that, in a sufficiently strong gravitational field, buckling is driven by compression in a region near the bottom of the sheet, and limited by viscous resistance to stretching of the sheet. We use asymptotic analysis in the thin-sheet, low-Reynolds-number limit to determine the centerline profile and growth rate of such a viscous sheet.

Systems, Apparatuses, and Methods for Using Durable Adhesively Bonded Joints for Sandwich Structures

NASA Technical Reports Server (NTRS)

Smeltzer, III, Stanley S. (Inventor); Lundgren, Eric C. (Inventor)

2014-01-01

Systems, methods, and apparatus for increasing durability of adhesively bonded joints in a sandwich structure. Such systems, methods, and apparatus includes an first face sheet and an second face sheet as well as an insert structure, the insert structure having a first insert face sheet, a second insert face sheet, and an insert core material. In addition, sandwich core material is arranged between the first face sheet and the second face sheet. A primary bondline may be coupled to the face sheet(s) and the splice. Further, systems, methods, and apparatus of the present disclosure advantageously reduce the load, provide a redundant path, reduce structural fatigue, and/or increase fatigue life.

Experimental investigation of a 1 kA/cm{sup 2} sheet beam plasma cathode electron gun

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, Niraj, E-mail: niraj.ceeri@gmail.com; Narayan Pal, Udit; Prajesh, Rahul

In this paper, a cold cathode based sheet-beam plasma cathode electron gun is reported with achieved sheet-beam current density ∼1 kA/cm{sup 2} from pseudospark based argon plasma for pulse length of ∼200 ns in a single shot experiment. For the qualitative assessment of the sheet-beam, an arrangement of three isolated metallic-sheets is proposed. The actual shape and size of the sheet-electron-beam are obtained through a non-conventional method by proposing a dielectric charging technique and scanning electron microscope based imaging. As distinct from the earlier developed sheet beam sources, the generated sheet-beam has been propagated more than 190 mm distance inmore » a drift space region maintaining sheet structure without assistance of any external magnetic field.« less

Observing the Heterogeneous Electro-redox of Individual Single-Layer Graphene Sheets.

PubMed

Chen, Tao; Zhang, Yuwei; Xu, Weilin

2016-09-27

Electro-redox-induced heterogeneous fluorescence of an individual single-layer graphene sheet was observed in real time by a total internal reflection fluorescence microscope. It was found that the fluorescence intensity of an individual sheet can be tuned reversibly by applying periodic voltages to control the redox degree of graphene sheets. Accordingly, the oxidation and reduction kinetics of an individual single-layer graphene sheet was studied at different voltages. The electro-redox-induced reversible variation of fluorescence intensity of individual sheets indicates a reversible band gap tuning strategy. Furthermore, correlation analysis of redox rate constants on individual graphene sheets revealed a redox-induced spatiotemporal heterogeneity or dynamics of graphene sheets. The observed controllable redox kinetics can rationally guide the precise band gap tuning of individual graphene sheets and then help their extensive applications in optoelectronics and devices for renewable energy.

Cell Sheet Stiffness Sensing without taking out from culture liquid.

PubMed

Uchida, Ryohei; Tanaka, Nobuyuki; Higashimori, Mitsuru; Tadakuma, Kenjiro; Kaneko, Makoto; Kondo, Makoto; Yamato, Masayuki

2010-01-01

Stiffness could be an important index for evaluating the vitality of cell sheet. This paper challenges the measurement of stiffness of transparent cell sheet in culture liquid without taking it out from petri dish. The system is composed of a micro air nozzle for supplying an air jet and a regular reflective type laser sensor for measuring the the deformation of transparent cell sheet. This system is called as Cell Sheet Stiffness Sensing system (CS(3) system). When an air jet is given to a cell sheet in culture liquid, it pushes away the liquid toward the outer direction at initial phase and reaches the surface of cell sheet. Without any switching motion, the air jet continuously imparts a force to the surface of cell sheet so that the sensor can measure the stiffness of the cell sheet.

FDTD modeling of thin impedance sheets

NASA Technical Reports Server (NTRS)

Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. In this paper it is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods.

A novel gelatin hydrogel carrier sheet for corneal endothelial transplantation.

PubMed

Watanabe, Ryou; Hayashi, Ryuhei; Kimura, Yu; Tanaka, Yuji; Kageyama, Tomofumi; Hara, Susumu; Tabata, Yasuhiko; Nishida, Kohji

2011-09-01

We examined the feasibility of using gelatin hydrogels as carrier sheets for the transplantation of cultivated corneal endothelial cells. The mechanical properties, transparency, and permeability of gelatin hydrogel sheets were compared with those of atelocollagen sheets. Immunohistochemistry (ZO-1, Na(+)/K(+)-ATPase, and N-cadherin), hematoxylin and eosin staining, and scanning electron microscopy were performed to assess the integrity of corneal endothelial cells that were cultured on gelatin hydrogel sheets. The gelatin hydrogel sheets displayed greater transparency, elastic modulus, and albumin permeability compared to those of atelocollagen sheets. The corneal endothelial cells on gelatin hydrogel sheets showed normal expression levels of ZO-1, Na(+)/K(+)-ATPase, and N-cadherin. Hematoxylin and eosin staining revealed the formation of a continuous monolayer of cells attached to the gelatin hydrogel sheet. Scanning electron microscopy observations showed that the corneal endothelial cells were arranged in a regular, mosaic, and polygonal pattern with normal cilia. These results indicate that the gelatin hydrogel sheet is a promising material to transport corneal endothelial cells during transplantation.

Solid oxide fuel cell with multi-unit construction and prismatic design

DOEpatents

McPheeters, C.C.; Dees, D.W.; Myles, K.M.

1999-03-16

A single cell unit of a solid oxide fuel cell is described that is individually fabricated and sintered prior to being connected to adjacent cells to form a solid oxide fuel cell. The single cell unit is comprised of a shaped anode sheet positioned between a flat anode sheet and an anode-electrolyte-cathode (A/E/C) sheet, and a shaped cathode sheet positioned between the A/E/C sheet and a cathode-interconnect-anode (C/I/A) sheet. An alternate embodiment comprises a shaped cathode sheet positioned between an A/E/C sheet and a C/I/A sheet. The shaped sheets form channels for conducting reactant gases. Each single cell unit is individually sintered to form a finished sub-assembly. The finished sub-assemblies are connected in electrical series by interposing connective material between the end surfaces of adjacent cells, whereby individual cells may be inspected for defects and interchanged with non-defective single cell units. 7 figs.

A panel method study of vortex sheets with special emphasis on sheets of axisymmetric geometry. M.S. Thesis

NASA Technical Reports Server (NTRS)

Sugioka, I.; Widnall, S. E.

1985-01-01

The self induced evolution of a vortex sheet was simulated by modeling the sheet using an integration of discrete elements of vorticity. Replacing small sections of a vortex sheet by flat panels of constant vorticity is found to reproduce more accurately the initial conditions for the Lagrangian simulation technique than replacement by point vortices. The flat panel method for the vortex sheet was then extended to model axisymmetric vortex sheets. The local and far field velocities induced by the axisymmetric panels were obtained using matched asymptotic analysis, and some of the uncertainties involved in other models of the axisymmetric vortex sheet have been eliminated. One important result of this analysis is the determination of the proper choice of core size for a circular vortex filament which may replace a section of an axisymmetric vortex sheet. Roll-up of both two dimensional and axisymmetric vortex sheets was computed using the panel methods developed in the report.

Battery plate containing filler with conductive coating

NASA Technical Reports Server (NTRS)

Rowlette, John J. (Inventor)

1986-01-01

The plate (10) comprises a matrix or binder resin phase (12) in which is dispersed particulate, conductive tin oxide such as tin oxide coated glass fibers (14). A monopolar plate (11) is prepared by coating a layer (18) of electrolytically active material onto a surface of the plate (10). Tin oxide is prevented from reduction by coating a surface of the plate (10) with a conductive, impervious layer resistant to reduction such as a thin film (22) of lead adhered to the plate with a layer (21) of conductive adhesive. The plate (10) can be formed by casting a molten dispersion from mixer (36) onto a sheet (30) of lead foil or by passing an assembly of a sheet (41) of resin, a sheet (43) of fiberglass and a sheet (45) of lead between the nip of heated rollers (48, 50).

Battery plate containing filler with conductive coating

NASA Technical Reports Server (NTRS)

Rowlette, John J. (Inventor)

1985-01-01

The plate (10) comprises a matrix or binder resin phase (12) in which is dispersed particulate, conductive tin oxide such as tin oxide coated glass fibers (14). A monopolar plate (11) is prepared by coating a layer (18) of electrolytically active material onto a surface of the plate (10). Tin oxide is prevented from reduction by coating a surface of the plate (10) with a conductive, impervious layer resistant to reduction such as a thin film (22) of lead adhered to the plate with a layer (21) of conductive adhesive. The plate (10) can be formed by casting a molten dispersion from mixer (36) onto a sheet (30) of lead foil or by passing an assembly of a sheet (41) of resin, a sheet (43) of fiberglass and a sheet (45) of lead between the nip of heated rollers (48, 50).

Two-dimensional boron: Lightest catalyst for hydrogen and oxygen evolution reaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mir, Showkat H.; Chakraborty, Sudip, E-mail: sudiphys@gmail.com, E-mail: prakash.jha@cug.ac.in; Wärnå, John

The hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) have been envisaged on a two-dimensional (2D) boron sheet through electronic structure calculations based on a density functional theory framework. To date, boron sheets are the lightest 2D material and, therefore, exploring the catalytic activity of such a monolayer system would be quite intuitive both from fundamental and application perspectives. We have functionalized the boron sheet (BS) with different elemental dopants like carbon, nitrogen, phosphorous, sulphur, and lithium and determined the adsorption energy for each case while hydrogen and oxygen are on top of the doping site of themore » boron sheet. The free energy calculated from the individual adsorption energy for each functionalized BS subsequently guides us to predict which case of functionalization serves better for the HER or the OER.« less

Modeling the effect of doping on the catalyst-assisted growth and field emission properties of plasma-grown graphene sheet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupta, Neha; Sharma, Suresh C.; Sharma, Rinku

A theoretical model describing the effect of doping on the plasma-assisted catalytic growth of graphene sheet has been developed. The model accounts the charging rate of the graphene sheet, kinetics of all the plasma species, including the doping species, and the growth rate of graphene nuclei and graphene sheet due to surface diffusion, and accretion of ions on the catalyst nanoparticle. Using the model, it is observed that nitrogen and boron doping can strongly influence the growth and field emission properties of the graphene sheet. The results of the present investigation indicate that nitrogen doping results in reduced thickness andmore » shortened height of the graphene sheet; however, boron doping increases the thickness and height of the graphene sheet. The time evolutions of the charge on the graphene sheet and hydrocarbon number density for nitrogen and boron doped graphene sheet have also been examined. The field emission properties of the graphene sheet have been proposed on the basis of the results obtained. It is concluded that nitrogen doped graphene sheet exhibits better field emission characteristics as compared to undoped and boron doped graphene sheet. The results of the present investigation are consistent with the existing experimental observations.« less

Texture and mechanical properties of Al-0.5Mg-1.0Si-0.5Cu alloy sheets manufactured via a cross rolling method

NASA Astrophysics Data System (ADS)

Jeon, Jae-Yeol; Son, Hyeon-Taek; Woo, Kee-Do; Lee, Kwang-Jin

2012-04-01

The relationship between the texture and mechanical properties of 6xxx aluminum alloy sheets processed via cross rolling was investigated. The microstructures of the conventional rolled and cross rolled sheets after annealing were analyzed using optical micrographs (OM). The texture distribution across the thickness in the Al-Mg-Si-Cu alloy, conventional rolled sheets, and cross rolled sheets both before and after annealing was investigated via X-ray texture measurements. The texture was analyzed in three layers from the surface to the center of the sheet. The β-fiber texture of the conventional rolled sheet was typical of the texture obtained using aluminumoll ring. After annealing, the typical β-fiber orientations were changed to recrystallization textures: cube{001}<100> and normal direction (ND)-rotated cubes. However, the texture of the cross rolled sheet was composed of an asymmetrical, rolling direction (RD)-rotated cubes. After annealing, the asymmetrical orientations in the cross rolled sheet were changed to a randomized texture. The average R-value of the annealed cross rolled sheets was higher than that of the conventional rolled sheets. The limit dome height (LDH) test results demonstrated that cross rolling is effective in improving the formability of the Al-Mg-Si-Cu alloy sheets.

The geomicrobiology of the Greenland Ice Sheet: impact on DOC export (Invited)

NASA Astrophysics Data System (ADS)

Wadham, J. L.; Stibal, M.; Lawson, E. C.; Barnett, M. J.; Hasan, F.; Telling, J.; Anesio, A.; Lis, G.; Cullen, D.; Butler, C.; Tranter, M.; Nienow, P. W.

2010-12-01

The Greenland Ice Sheet (GrIS) is the largest mass of ice in the northern hemisphere, and contributes ~370 km3 in runoff annually to the Arctic Ocean. While recent work has highlighted runoff increases of up to 100% from the GrIS over the next century, very little is known about the associated impacts upon rates of sediment-bound and dissolved organic carbon export from the ice sheet to the coastal ocean. This is relevant given recent work that has suggested that the high proportion of labile dissolved organic carbon (DOC) present in glacial runoff may be important in sustaining the productivity of ecosystems downstream. Here we report the phylogenetic and functional diversity of micro-organisms inhabiting the surface and basal regions of the Greenland Ice Sheet (at Leverett Glacier, SW Greenland), and whose activity influences the biogeochemical composition of runoff. Real time PCR data on runoff, together with 16S-rRNA bacterial clone libraries on sediments, demonstrate a subglacial microbial community that contrasts phylogenetically and functionally with the ice sheet surface ecosystem. We envisage that large sectors of the subglacial environment are microbially active, with overridden paleosols and in-washed surface organic matter providing a carbon substrate for a range of metabolic pathways. This includes methanogenesis which proceeds at rates similar to deep ocean sediments and via a CO2/H2 pathway. These subglacial microbial communities serve to chemically modify the DOC composition of meltwater inputs from the ice sheet surface and modulate the reactivity of bulk DOC exported in runoff. Evidence for subglacial microbial influences on DOC in runoff includes elevated concentrations of dissolved carbohydrates (e.g. glucose and fructose of up to 1 μmol/L), which are preferentially exported during subglacial outburst events. We examine the temporal changes in DOC export in runoff from the ice sheet over a full melt season, and consider how changes in total runoff over the coming century may perturb this contribution.

Nonlinear distortion of thin liquid sheets

NASA Astrophysics Data System (ADS)

Mehring, Carsten Ralf

Thin planar, annular and conical liquid sheets or films are analyzed, in a unified manner, by means of a reduced- dimension approach providing governing equations for the nonlinear motion of planar and swirling annular thin inviscid and incompressible liquid sheets in zero gravity and with axial disturbances only. Temporal analyses of periodically disturbed infinite sheets are considered, as well as spatial analyses of semi-infinite sheets modulated at the nozzle exit. Results on planar and swirling annular or conical sheets are presented for a zero density ambient gas. Here, conical sheets are obtained in the nearfield of the nozzle exit by considering sheets or films with swirl in excess of that needed to stabilize the discharging stream in its annular configuration. For nonswirling annular sheets a spatially and/or temporally constant gas-core pressure is assumed. A model extension considering the influence of aerodynamic effects on planar sheets is proposed. For planar and annular sheets, linear analyses of the pure initial- and pure boundary-value problem provide insight into the propagation characteristics of dilational and sinuous waves, the (linear) coupling between both wave modes, the stability limits for the annular configuration, as well as the appearance of particular waves on semi-infinite modulated sheets downstream from the nozzle exit. Nonlinear steady-state solutions for the conical configuration (without modulation) are illustrated. Comparison between nonlinear and linear numerical and linear analytical solutions for temporally or spatially developing sheets provides detailed information on the nonlinear distortion characteristics including nonlinear wave propagation and mode-coupling for all the considered geometric configurations and for a variety of parameter configurations. Sensitivity studies on the influence of Weber number, modulation frequency, annular radius, forcing amplitude and sheet divergence on breakup or collapse length and times are reported for modulated semi-infinite annular and conical sheets. Comparisons between the different geometric configurations are made. For periodically disturbed planar sheets, accuracy of the employed reduced-dimension approach is demonstrated by comparison with more accurate two-dimensional vortex dynamics simulations.

The Role of Ionospheric O+ in Forming the Storm-time Ring Current

NASA Astrophysics Data System (ADS)

Kistler, L. M.; Mouikis, C.; Menz, A.; Bingham, S.

2017-12-01

During storm times, the particle pressure that creates the storm-time ring current in the inner magnetosphere can be dominated by O+. This is surprising, as the immediate source for the ring current is the nightside plasma sheet, and O+ is usually not the dominant species in the plasma sheet. In this talk we examine the many factors that lead to this result. The O+ outflow is enhanced during geomagnetically active times. The transport paths of O+ and H+ are different, such that the O+ that reaches the near-earth plasma sheet is more energetic than H+. The source spectrum in the near-earth plasma sheet can be harder for O+ than for H+, perhaps due to substorm injections, so that the more energetic plasma has a higher O+/H+ ratio. And finally the plasma sheet O+ can be more abundant towards the beginning of the storm, when the convection is largest, so the enhanced O+ is brought the deepest into the inner magnetosphere. We will discuss the interrelationships between these different effects as well as the ways in which O+ itself may influence the system.

H+ and O+ dynamics during ultra-low frequency waves in the Earth's magnetotail plasma sheet

NASA Astrophysics Data System (ADS)

De Spiegeleer, Alexandre; Hamrin, Maria; Pitkänen, Timo; Volwerk, Martin; Mouikis, Christopher; Kistler, Lynn; Nilsson, Hans; Norqvist, Patrik; Andersson, Laila

2017-04-01

The concentration of ionospheric oxygen (O^+) in the magnetotail plasma sheet can be relatively elevated depending on, for instance, the geomagnetic activity as well as the solar cycle. The dynamics of the tail plasma sheet can be affected by the presence of O+ via for example the generation of instabilities such as the Kelvin-Helmholtz instability. However, the O+ is not always taken into account when studying the dynamics of the tail plasma sheet. We investigate proton (H^+) and O+ during ultra-low frequency waves (period > 5 min) in the mid-tail plasma sheet (beyond 10R_E) using Cluster data. We observe that the velocity of O+ can be significantly different from that of H^+. When occuring, this velocity difference always seems to be in the direction parallel to the magnetic field. The parallel velocity of the two species can be observed to be somewhat out of phase, meaning that while one species flows in the parallel direction, the other flows in the anti-parallel direction. Possible causes for such large discrepancies between the dynamics of O+ and H+ are discussed.

Energization of the Ring Current through Convection of Substorm Enhancements of the Plasma Sheet Source.

NASA Astrophysics Data System (ADS)

Menz, A.; Kistler, L. M.; Mouikis, C.; Spence, H. E.; Henderson, M. G.; Matsui, H.

2017-12-01

It has been shown that electric field strength and night-side plasma sheet density are the two best predictors of the adiabatic energy gain of the ring current during geomagnetic storms (Liemohn and Khazanov, 2005). While H+ dominates the ring current during quiet times, O+ can contribute substantially during geomagnetic storms. Substorm activity provides a mechanism to enhance the energy density of O+ in the plasma sheet during geomagnetic storms, which is then convected adiabatically into the inner-magnetosphere. Using the Van Allen Probes data in the the plasma sheet source region (defined as L>5.5 during storms) and the inner magnetosphere, along with LANL-GEO data to identify substorm injection times, we show that adiabatic convection of O+ enhancements in the source region can explain the observed enhancements in the inner magnetosphere. We use the UNH-IMEF electric field model to calculate drift times from the source region to the inner magnetosphere to test whether enhancements in the inner-magnetosphere can be explained by dipolarization driven enhancements in the plasma sheet source hours before.

Electric fields measured by ISEE-1 within and near the neutral sheet during quiet and active times

NASA Technical Reports Server (NTRS)

Cattell, C. A.; Mozer, F. S.

1982-01-01

An understanding of the physical processes occurring in the magnetotail and plasmasheet during different interplanetary magnetic field orientations and differing levels of ground magnetic activity is crucial for the development of a theory of energy transfer from the solar wind to the particles which produce auroral arcs. In the present investigation, the first observations of electric fields during neutral sheet crossings are presented, taking into account the statistical correlations of the interplanetary magnetic field direction and ground activity with the character of the electric field. The electric field data used in the study were obtained from a double probe experiment on the ISEE-1 satellite. The observations suggest that turbulent electric and magnetic fields are intimately related to plasma acceleration in the neutral sheet and to the processes which create auroral particles.

Calcium imaging of neural circuits with extended depth-of-field light-sheet microscopy

PubMed Central

Quirin, Sean; Vladimirov, Nikita; Yang, Chao-Tsung; Peterka, Darcy S.; Yuste, Rafael; Ahrens, Misha B.

2016-01-01

Increasing the volumetric imaging speed of light-sheet microscopy will improve its ability to detect fast changes in neural activity. Here, a system is introduced for brain-wide imaging of neural activity in the larval zebrafish by coupling structured illumination with cubic phase extended depth-of-field (EDoF) pupil encoding. This microscope enables faster light-sheet imaging and facilitates arbitrary plane scanning—removing constraints on acquisition speed, alignment tolerances, and physical motion near the sample. The usefulness of this method is demonstrated by performing multi-plane calcium imaging in the fish brain with a 416 × 832 × 160 µm field of view at 33 Hz. The optomotor response behavior of the zebrafish is monitored at high speeds, and time-locked correlations of neuronal activity are resolved across its brain. PMID:26974063

Optical modulator including grapene

DOEpatents

Liu, Ming; Yin, Xiaobo; Zhang, Xiang

2016-06-07

The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

14 CFR Section 6 - Objective Classification of Balance Sheet Elements

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Objective Classification of Balance Sheet... AIR CARRIERS Balance Sheet Classifications Section 6 Objective Classification of Balance Sheet...) Record here all general and working funds available on demand as of the date of the balance sheet which...

14 CFR Section 6 - Objective Classification of Balance Sheet Elements

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Objective Classification of Balance Sheet... AIR CARRIERS Balance Sheet Classifications Section 6 Objective Classification of Balance Sheet...) Record here all general and working funds available on demand as of the date of the balance sheet which...

47 CFR 32.101 - Structure of the balance sheet accounts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Structure of the balance sheet accounts. 32.101... UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.101 Structure of the balance sheet accounts. The Balance Sheet accounts shall be maintained as follows...

47 CFR 32.101 - Structure of the balance sheet accounts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Structure of the balance sheet accounts. 32.101... UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.101 Structure of the balance sheet accounts. The Balance Sheet accounts shall be maintained as follows...

Transporter for Treated Sheet Materials

NASA Technical Reports Server (NTRS)

Pollack, M., H.

1983-01-01

Plastic spacers keep parts separated during transport or storage. Cart with rods and spacers holds sheets with delicate finishes for storage or transport. Sheets supported vertically by rods, or horizontally. Spacers keep sheets separated. Designed to eliminate time and expense of tapping, wrapping, and sometimes refinishing aluminum sheets with delicate anodized finished.

Highly Conductive Flexible Multi-Walled Carbon Nanotube Sheet Films for Transparent Touch Screen

NASA Astrophysics Data System (ADS)

Jung, Daewoong; Lee, Kyung Hwan; Kim, Donghyun; Burk, Dorothea; Overzet, Lawrence J.; Lee, Gil Sik

2013-03-01

Highly conductive and transparent thin films were prepared using highly purified multi-walled carbon nanotube (MWCNT) sheets. The electrical properties of the MWCNT sheet were remarkably improved by an acid treatment, resulting in densely packed MWCNTs. The morphology of the sheets reveals that continuous electrical pathways were formed by the acid treatment, greatly improving the sheet resistance all the while maintaining an excellent optical transmittance. These results encourage the use of these MWCNT sheets with low sheet resistance (450 Ω/sq) and high optical transmittance (90%) as a potential candidate for flexible display applications.

Stacked endoplasmic reticulum sheets are connected by helicoidal membrane motifs

PubMed Central

Terasaki, Mark; Shemesh, Tom; Kasthuri, Narayanan; Klemm, Robin W.; Schalek, Richard; Hayworth, Kenneth J.; Hand, Arthur R.; Yankova, Maya; Huber, Greg; Lichtman, Jeff W.; Rapoport, Tom A.; Kozlov, Michael M.

2013-01-01

The endoplasmic reticulum (ER) often forms stacked membrane sheets, an arrangement that is likely required to accommodate a maximum of membrane-bound polysomes for secretory protein synthesis. How sheets are stacked is unknown. Here, we used novel staining and automated ultra-thin sectioning electron microscopy methods to analyze stacked ER sheets in neuronal cells and secretory salivary gland cells of mice. Our results show that stacked ER sheets form a continuous membrane system in which the sheets are connected by twisted membrane surfaces with helical edges of left- or right-handedness. The three-dimensional structure of tightly stacked ER sheets resembles a parking garage, in which the different levels are connected by helicoidal ramps. A theoretical model explains the experimental observations and indicates that the structure corresponds to a minimum of elastic energy of sheet edges and surfaces. The structure allows the dense packing of ER sheets in the restricted space of a cell. PMID:23870120

Sheet, ligament and droplet formation in swirling primary atomization

NASA Astrophysics Data System (ADS)

Shao, Changxiao; Luo, Kun; Chai, Min; Fan, Jianren

2018-04-01

We report direct numerical simulations of swirling liquid atomization to understand the physical mechanism underlying the sheet breakup of a non-turbulent liquid swirling jet which lacks in-depth investigation. The volume-of-fluid (VOF) method coupled with adapted mesh refinement (AMR) technique in GERRIS code is employed in the present simulation. The mechanisms of sheet, ligament and droplet formation are investigated. It is observed that the olive-shape sheet structure is similar to the experimental result qualitatively. The numerical results show that surface tension, pressure difference and swirling effect contribute to the contraction and extension of liquid sheet. The ligament formation is partially at the sheet rim or attributed to the extension of liquid hole. Especially, the movement of hairpin vortex exerts by an anti-radial direction force to the sheet surface and leads to the sheet thinness. In addition, droplet formation is attributed to breakup of ligament and central sheet.

Method of fabricating metal- and ceramic- matrix composites and functionalized textiles

DOEpatents

Maxwell, James L [Jemez Springs, NM; Chavez, Craig A [Los Alamos, NM; Black, Marcie R [Lincoln, MA

2012-04-17

A method of manufacturing an article comprises providing a first sheet, wetting the first sheet with a liquid precursor to provide a first wet sheet, and irradiating the first wet sheet in a pattern corresponding to a first cross section of the article such that the liquid precursor is at least partially converted to a solid in the first cross section. A second sheet is disposed adjacent to the first sheet. The method further comprises wetting the second sheet with the liquid precursor to provide a second wet sheet, and irradiating the second wet sheet in a pattern corresponding to a second cross section of the article such that the liquid precursor is at least partially converted to a solid in the second cross section. In particular the liquid precursor may be converted to a metal, ceramic, semiconductor, semimetal, or a combination of these materials.

Dual circuit embossed sheet heat transfer panel

DOEpatents

Morgan, G.D.

1984-02-21

A heat transfer panel provides redundant cooling for fusion reactors or the like environment requiring low-mass construction. Redundant cooling is provided by two independent cooling circuits, each circuit consisting of a series of channels joined to inlet and outlet headers. The panel comprises a welded joinder of two full-size and two much smaller partial-size sheets. The first full-size sheet is embossed to form first portions of channels for the first and second circuits, as well as a header for the first circuit. The second full-sized sheet is then laid over and welded to the first full-size sheet. The first and second partial-size sheets are then overlaid on separate portions of the second full-sized sheet, and are welded thereto. The first and second partial-sized sheets are embossed to form inlet and outlet headers, which communicate with channels of the second circuit through apertures formed in the second full-sized sheet. 6 figs.

Dual-circuit embossed-sheet heat-transfer panel

DOEpatents

Morgan, G.D.

1982-08-23

A heat transfer panel provides redundant cooling for fusion reactors or the like environment requiring low-mass construction. Redundant cooling is provided by two independent cooling circuits, each circuit consisting of a series of channels joined to inlet and outlet headers. The panel comprises a welded joinder of two full-size and two much smaller partial-size sheets. The first full-size sheet is embossed for form first portions of channels for the first and second circuits, as well as a header for the first circuit. The second full-sized sheet is then laid over and welded to the first full-size sheet. The first and second partial-size sheets are then overlaid on separate portions of the second full-sized sheet, and are welded thereto. The first and second partial-sized sheets are embossed to form inlet and outlet headers, which communicate with channels of the second circuit through apertures formed in the second full-sized sheet.

Dual circuit embossed sheet heat transfer panel

DOEpatents

Morgan, Grover D.

1984-01-01

A heat transfer panel provides redundant cooling for fusion reactors or the like environment requiring low-mass construction. Redundant cooling is provided by two independent cooling circuits, each circuit consisting of a series of channels joined to inlet and outlet headers. The panel comprises a welded joinder of two full-size and two much smaller partial-size sheets. The first full-size sheet is embossed to form first portions of channels for the first and second circuits, as well as a header for the first circuit. The second full-sized sheet is then laid over and welded to the first full-size sheet. The first and second partial-size sheets are then overlaid on separate portions of the second full-sized sheet, and are welded thereto. The first and second partial-sized sheets are embossed to form inlet and outlet headers, which communicate with channels of the second circuit through apertures formed in the second full-sized sheet.

Sectional Finite Element Analysis on Viscous Pressure Forming of Sheet Metal

NASA Astrophysics Data System (ADS)

Liu, Jianguang; Wang, Zhongjin; Liu, Yan

2007-05-01

Viscous pressure forming (VPF) is a recently developed sheet flexible-die forming process, which uses a kind of semi-solid, flowable and viscous material as pressure-carrying medium that typically applied on one side of the sheet metal or on both sides of sheet metal. Different from traditional sheet metal forming processes in which sheet metal is the unique deformation-body, VPF is a coupling process of visco-elastoplastic bulk deformation of viscous medium and elasto-plastic deformation of sheet metal. A sectional finite element model for the coupled deformation between visco-elastoplastic body and elasto-plastic sheet metal was proposed to analyze VPF. The resolution of the Updated Lagrangian formulation is based on a static approach. By using static-explicit time integration strategy, the deformation of elasto-plastic sheet metal and visco-elastoplastic body can keep stable. The frictional contact between sheet metal and visco-elastoplastic body is treated by penalty function method. Using the proposed algorithm, sheet metal viscous pressure bulging (VPB) process is analyzed and compared with experiments. A good agreement between numerical simulation results and experimental ones proved the efficiency and stability of this algorithm.

Study of GO-Cu2O and RGO-Cu nanocomposite monolayer sheets prepared by modified Langmuir Blodgett route

NASA Astrophysics Data System (ADS)

Botcha, V. Divakar; Sutar, D. S.; Major, S. S.

2018-07-01

The modified Langmuir-Blodgett (MLB) technique has been improvised and extended to transfer GO-Cu2O nanocomposite monolayer sheets, by introducing Cu2+ ions into the subphase at room temperature. Morphological studies of as-transferred sheets revealed the presence of closely spaced GO monolayer sheets, with slightly enhanced roughness. XPS studies of as-transferred sheets confirmed the presence of copper, either as metallic Cu or Cu2O, along with significant Cu(OH)2 component, but TEM results confirmed the formation of Cu2O nanocrystallites of size (7 ± 2) nm, distributed uniformly over GO sheets. After heat treatment in vacuum at 400 °C, the nanocomposite sheets were covered with a uniform distribution of larger size nanoparticles. Based on Raman, XPS and TEM studies it has been confirmed that heat treatment at 400 °C in vacuum results in the formation of agglomerated Cu nanoparticles of size (23 ± 9) nm distributed uniformly over reduced graphene oxide (RGO) sheets. The electrical characterization of nanocomposite sheets on SiO2/Si in back-gated FET geometry revealed that the electrical conductivity of as-transferred GO-Cu2O sheets was similar to that usually observed for GO monolayer sheets. The RGO-Cu sheets also displayed electrical conductivity and field effect mobility values comparable to those reported for RGO sheets obtained by chemical/thermal reduction, and was unaffected by the presence of Cu nanoparticles.

Electromagnetic augmentation for casting of thin metal sheets

DOEpatents

Hull, John R.

1989-01-01

Thin metal sheets are cast by magnetically levitating molten metal deposited in a mold within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled by the water-cooled walls of the mold to form a solid metal sheet. A conducting shield is electrically coupled to the molten metal sheet to provide a return path for eddy currents induced in the metal sheet by the current in the AC conducting coils. In another embodiment, a DC conducting coil is coupled to the metal sheet for providing a direct current therein which interacts with the magnetic field to levitate the moving metal sheet. Levitation of the metal sheet in both molten and solid forms reduces its contact pressure with the mold walls while maintaining sufficient engagement therebetween to permit efficient conductive cooling by the mold through which a coolant fluid may be circulated. The magnetic fields associated with the currents in the aforementioned coils levitate the molten metal sheet while the mold provides for its lateral and vertical confinement. A leader sheet having electromagnetic characteristics similar to those of the molten metal sheet is used to start the casing process and precedes the molten metal sheet through the yoke/coil arrangement and mold and forms a continuous sheet therewith. The yoke/coil arrangement may be either U-shaped with a single racetrack coil or may be rectangular with a pair of spaced, facing bedstead coils.

The Great Balancing Act. Nutrition Comes Alive. Level 4. Nutrition Educator's Guide and Work Sheets, Information Sheets, Story, Letters to Parents. Revised Edition.

ERIC Educational Resources Information Center

Waldron, Laurie

This guide offers a nutrition education program for students in Kindergarten through Grade 6. Activities span all grades as well as activities for the specific level. Nutrition education objectives are stated for each grade level: (1) grade four--students will explore how to balance food intake and energy output for overall health and physical…

Analysis of low-dose radiation shield effectiveness of multi-gate polymeric sheets

NASA Astrophysics Data System (ADS)

Kim, S. C.; Lee, H. K.; Cho, J. H.

2014-07-01

Computed tomography (CT) uses a high dose of radiation to create images of the body. As patients are exposed to radiation during a CT scan, the use of shielding materials becomes essential in CT scanning. This study was focused on the radiation shielding materials used for patients during a CT scan. In this study, sheets were manufactured to shield the eyes and the thyroid, the most sensitive parts of the body, against radiation exposure during a CT scan. These sheets are manufactured using silicone polymers, barium sulfate (BaSO4) and tungsten, with the aim of making these sheets equally or more effective in radiation shielding and more cost-effective than lead sheets. The use of barium sulfate drew more attention than tungsten due to its higher cost-effectiveness. The barium sulfate sheets were coated to form a multigate structure by applying the maximum charge rate during the agitator and subsequent mixing processes and creating multilayered structures on the surface. To measure radiation shielding effectiveness, the radiation dose was measured around both eyes and the thyroid gland using sheets in three different thicknesses (1, 2 and 3 mm). Among the 1 and 2 mm sheets, the Pb sheets exhibited greater effectiveness in radiation shielding around both eyes, but the W sheets were more effective in radiation shielding around the thyroid gland. In the 3 mm sheets, the Pb sheet also attenuated a higher amount of radiation around both eyes while the W sheet was more effective around the thyroid gland. In conclusion, the sheets made from barium sulfate and tungsten proved highly effective in shielding against low-dose radiation in CT scans without causing ill-health effects, unlike lead.

26 CFR 301.6501(c)-1 - Exceptions to general period of limitations on assessment and collection.

Code of Federal Regulations, 2011 CFR

2011-04-01

... taxable event), including, in the case of an equity interest that is not actively traded, the financial and other data used in determining value. Financial data should generally include balance sheets and... of property transferred, including any financial data (for example, balance sheets, etc. with...

26 CFR 301.6501(c)-1 - Exceptions to general period of limitations on assessment and collection.

Code of Federal Regulations, 2010 CFR

2010-04-01

... taxable event), including, in the case of an equity interest that is not actively traded, the financial and other data used in determining value. Financial data should generally include balance sheets and... of property transferred, including any financial data (for example, balance sheets, etc. with...

College Experience and Volunteering. Fact Sheet

ERIC Educational Resources Information Center

Marcelo, Karlo Barrios

2007-01-01

College experience and volunteering are positively correlated. Measurable differences in civic activity exist between young people who attend college and young people who do not. This fact sheet explores volunteering as civic engagement among youth with college experience, ages 19-25, which was down for the second year in a row in 2006. The…

Agricultural Science I. Supplementary Units. Instructor Information.

ERIC Educational Resources Information Center

Martin, Donna; And Others

These supplementary units are designed to help students with special needs learn and apply agricultural skills in the areas of animal breeding, animal nutrition, leadership, and power tools. Specific competencies are listed as study questions at the beginning of each of the 10 self-paced and self-contained units. Skill sheets, activity sheets, and…

Fractional Parts. Elementary Module for Use in a Mathematics Laboratory Setting.

ERIC Educational Resources Information Center

Charbonneau, Manon P.

This module, concerned with fractional parts, contains 15 activity sheets, 12 of these involve students in making fractional parts and discovering the relationships of less than, equal to, and greater than, between different fractional parts. The last three sheets are for extending and enriching experiences with fractional parts. Teaching…

Major Appliance Repair. Teacher Edition and Student Edition. Second Edition.

ERIC Educational Resources Information Center

Smreker, Gene; Calvert, King

This second edition contains teacher and student guides for 14 units of instruction in major appliance repair. Each unit in the teacher edition includes some or all of the following basic components: objective sheet, suggested activities, answers to assignment sheets, answers to the written test, written test, a unit evaluation form, teacher…

Geri Keams: "Coyote and Spider Woman and Other Creation Stories." Cue Sheet.

ERIC Educational Resources Information Center

Carr, Gail

This performance guide is designed for teachers to use with students before and after a storytelling performance of "Coyote and Spider Woman and Other Creation Stories," by Geri Keams, a Navajo storyteller. The guide, called a "Cuesheet," contains seven activity sheets for use in class, addressing: (1) The Storyteller Tells Her…

State Arts Agency Fact Sheet: Support for Arts Education

ERIC Educational Resources Information Center

Online Submission, 2015

2015-01-01

This national overview of state arts agency grants and services for arts education includes summary statistics and geographic distribution. The fact sheet uses data from Final Descriptive Reports of state arts agency grant-making activities submitted annually to the National Assembly of State Arts Agencies (NASAA) and the National Endowment for…

Improving Reading in Every Class: A Sourcebook for Teachers.

ERIC Educational Resources Information Center

Thomas, Ellen Lamar; Robinson, H. Alan

This sourcebook for high school teachers suggests procedures not only for teaching the fundamental process of reading, but also for teaching reading in all of the high school content areas. It features motivating activities, a subject-area index, and guide sheets and work sheets. Chapters include "How to Use This Book,""Building Vocabulary and…

Nested seaweed cellulose fiber deposited with cuprous oxide nanorods for antimicrobial activity.

PubMed

Bhutiya, Priyank L; Misra, Nirendra; Abdul Rasheed, M; Zaheer Hasan, S

2018-05-30

Bird's nest type architectural network of cellulosic nanofibers was extracted, with nearly 34% yield, from green filamentous seaweed Chaetomorpha antennina using mild bleaching agent. Nanorods of cuprous oxide (Cu 2 O) were grown over the porous sheet, prepared from the seaweed cellulose, by one step hydrothermal method. The seaweed cellulose and Cu 2 O nanorods deposited seaweed cellulose sheets, were characterized by XRD, SEM-EDX, FT-IR, TGA and tensile test. XRD revealed that seaweed cellulose acted as reducing agent, reducing CuO to Cu 2 O. Morphology showed that the average diameter of seaweed cellulose and deposited Cu 2 O nanorods were 30 nm and 90 nm, respectively. Cuprous oxide nanorods deposited seaweed cellulose sheet gave very good antibacterial activity towards gram-positive (Staphylococcus aureus, Streptococcus thermophilis) and gram-negative (Pseudomonas aeruginous, Escherichia coli) microbes. The Cu 2 O nanorods deposited seaweed cellulose sheet can be viewed to have great potential in biomedical, packaging, biotechnological, textile, water treatment and pharmaceutical applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Growth Factor-Reinforced ECM Fabricated from Chemically Hypoxic MSC Sheet with Improved In Vivo Wound Repair Activity.

PubMed

Du, Hui-Cong; Jiang, Lin; Geng, Wen-Xin; Li, Jing; Zhang, Rui; Dang, Jin-Ge; Shu, Mao-Guo; Li, Li-Wen

2017-01-01

MSC treatment can promote cutaneous wound repair through multiple mechanisms, and paracrine mediators secreted by MSC are responsible for most of its therapeutic benefits. Recently, MSC sheet composed of live MSCs and their secreted ECMs was reported to promote wound healing; however, whether its ECM alone could accelerate wound closure remained unknown. In this study, Nc-ECM and Cc-ECM were prepared from nonconditioned and CoCl 2 -conditioned MSC sheets, respectively, and their wound healing properties were evaluated in a mouse model of full-thickness skin defect. Our results showed that Nc-ECM can significantly promote wound repair through early adipocyte recruitment, rapid reepithelialization, enhanced granulation tissue growth, and augmented angiogenesis. Moreover, conditioning of MSC sheet with CoCl 2 dramatically enriched its ECM with collagen I, collagen III, TGF- β 1, VEGF, and bFGF via activation of HIF-1 α and hence remarkably improved its ECM's in vivo wound healing potency. All the Cc-ECM-treated wounds completely healed on day 7, while Nc-ECM-treated wounds healed about 85.0% ± 8.6%, and no-treatment wounds only healed 69.8% ± 9.6% ( p < 0.05). Therefore, we believe that such growth factor-reinforced ECM fabricated from chemically hypoxic MSC sheet has the potential for clinical translation and will lead to a MSC-derived, cost-effective, bankable biomaterial for wound management.

46 CFR 160.055-1 - Incorporation by reference.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... 160.055-IA: Sheet 1—Construction and Arrangement, Vinyl Dip Coated, Model 62, Adult. Sheet 2—Construction and Arrangement, Vinyl Dip Coated, Model 66, Child. Dwg. No. 160.055-IB: Sheet 1—Construction and Arrangement, Cloth Covered, Model 63, Adult. Sheet 2—Buoyant Inserts, Model 63. Sheet 3—Construction and...

12 CFR 615.5211 - Risk categories-balance sheet assets.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Risk categories-balance sheet assets. 615.5211...—balance sheet assets. Section 615.5210(c) specifies certain balance sheet assets that are not assigned to the risk categories set forth below. All other balance sheet assets are assigned to the percentage...

12 CFR 615.5211 - Risk categories-balance sheet assets.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Risk categories-balance sheet assets. 615.5211...—balance sheet assets. Section 615.5210(c) specifies certain balance sheet assets that are not assigned to the risk categories set forth below. All other balance sheet assets are assigned to the percentage...

Strain and mechanical properties of the VCM multilayer sheet and their composites using the digital speckle correlation method.

PubMed

Zhang, Dehai; Xie, Guizhong; Li, Yanqin; Liu, Jianxiu

2015-09-01

The digital speckle correlation method (DSCM) is introduced to solve the challenging problems in the related geometric measurement. Theoretical calculations of strain are deduced using the DSCM. Corresponding strains along x and y directions are obtained from uniaxial tension experiments and digital speckle measurements, using the VCM nondeep drawing multilayer sheet, the VCM deep-drawing multilayer sheet, clad films, nondeep drawing substrate, and deep-drawing substrate sheet as the targeted experimental objects. The results show that the maximum strains along the x direction of the VCM nondeep drawing multilayer sheet, the VCM deep-drawing multilayer sheet, clad film, nondeep drawing substrate, and deep-drawing substrate sheet are 68.473%, 48.632%, 91.632%, 50.784% and 40.068%, respectively, while the maximum strains along the y direction are -2.657%, -15.381%, 2.826%, -9.780% and -7.783%, respectively. The mechanical properties of the VCM multilayer sheet are between those of the substrate and clad film, while mechanical properties of the VCM deep-drawing multilayer sheet are superior to those of the VCM nondeep drawing multi-layer sheet.

Triple-glazed insulating unit with improved edge insulation

DOEpatents

Goodwin, George B.; Buchanan, Michael J.

2016-06-07

An insulating unit includes a first spacer frame between first and second sheets, e.g. glass sheets, and a second spacer frame between the second sheet and a third sheet. A first surface of the first spacer frame is adhered to inner surface of the first sheet, and an opposite second surface of the first spacer frame is adhered to a first surface of the second sheet, by a moisture impervious adhesive layer. A first outer surface of the second spacer frame is adhered to a second surface of the second sheet, and an opposite second outer surface of the second spacer frame is adhered to an inner surface of the third sheet, by the adhesive layer. The first spacer frame and the second spacer frame have an offset of greater than zero.

Twin-Mirrored-Galvanometer Laser-Light-Sheet Generator

NASA Technical Reports Server (NTRS)

Rhodes, David B.; Franke, John M.; Jones, Stephen B.; Leighty, Bradley D.

1991-01-01

Multiple, rotating laser-light sheets generated to illuminate flows in wind tunnels. Designed and developed to provide flexibility and adaptability to wide range of applications. Design includes capability to control size and location of laser-light sheet in real time, to generate horizontal or vertical sheets, to sweep sheet repeatedly through volume, to generate multiple sheets with controllable separation, and to rotate single or multiple laser-light sheets. Includes electronic equipment and laser mounted on adjustable-height platform. Twin-mirrored galvanometer unit supported by tripod to reduce vibration. Other possible applications include use in construction industry to align beams of building. Artistic or display applications also possible.

LIVVkit 2: An extensible land ice verification and validation toolkit for comparing observations and models?

NASA Astrophysics Data System (ADS)

Kennedy, J. H.; Bennett, A. R.; Evans, K. J.; Fyke, J. G.; Vargo, L.; Price, S. F.; Hoffman, M. J.

2016-12-01

Accurate representation of ice sheets and glaciers are essential for robust predictions of arctic climate within Earth System models. Verification and Validation (V&V) is a set of techniques used to quantify the correctness and accuracy of a model, which builds developer/modeler confidence, and can be used to enhance the credibility of the model. Fundamentally, V&V is a continuous process because each model change requires a new round of V&V testing. The Community Ice Sheet Model (CISM) development community is actively developing LIVVkit, the Land Ice Verification and Validation toolkit, which is designed to easily integrate into an ice-sheet model's development workflow (on both personal and high-performance computers) to provide continuous V&V testing.LIVVkit is a robust and extensible python package for V&V, which has components for both software V&V (construction and use) and model V&V (mathematics and physics). The model Verification component is used, for example, to verify model results against community intercomparisons such as ISMIP-HOM. The model validation component is used, for example, to generate a series of diagnostic plots showing the differences between model results against observations for variables such as thickness, surface elevation, basal topography, surface velocity, surface mass balance, etc. Because many different ice-sheet models are under active development, new validation datasets are becoming available, and new methods of analysing these models are actively being researched, LIVVkit includes a framework to easily extend the model V&V analyses by ice-sheet modelers. This allows modelers and developers to develop evaluations of parameters, implement changes, and quickly see how those changes effect the ice-sheet model and earth system model (when coupled). Furthermore, LIVVkit outputs a portable hierarchical website allowing evaluations to be easily shared, published, and analysed throughout the arctic and Earth system communities.

Geoologic controls on the architecture of the Antarctic Ice Sheet's basal interface: New results from West and East Antarctica from long range geophysics (Invited)

NASA Astrophysics Data System (ADS)

Young, D. A.; Blankenship, D. D.; Greenbaum, J. S.; Richter, T.; Aitken, A.; Siegert, M. J.; Roberts, J. L.

2013-12-01

The ice-rock interface underlying the Antarctic Ice Sheet was shaped by interactions between underlying gondwanan geology and the overlying ice sheet. The ice sheet now preserves from sedimentary infill an incredibly rugged terrain which now plays a critical role in shaping subglacial hydrology, and thus shape ice sheet behavior. This terrain can by imaged through aerogeophysical means, in particular through ice penetrating radar, while airborne potential fields measurements provide insight into the geological framework that controlled erosion. Over the post IPY era, the density of airborne coverage is only now reaching the point where small scale structure can be identified and placed in context. Of particular importance is understanding the formation of focused erosional valleys, 30-50 km wide, representing now buried subglacial fjords. After initial data from the GIMBLE project in West Antarctica, and five years of sustained long range ICECAP surveys over East Antarctica , we now have a better view of the diversity of these features. The local erosion of these valleys, often cutting through significant topographic barriers, irregularly samples the underlying geology, provided a complex story in the sediment to the Antarctic margin. These valleys now provide the subglacial conduits for significant ice sheet catchments, in particular for subglacial water, including the inland catchments of DeVicq, Thwaites, and Pine Island Glaciers in West Antarctica, and Denman Glacier, Totten Glacier, Byrd Glacier and Cook Ice Shelf in East Antarctica. We find that these features, now sometimes hundreds of kilometers inland of the modern grounding line, often nucleate on or are aligned with structure inherited from the assembly of the Antarctic continent. While many of these features currently host active outlet glaciers or their tributaries, some do not, implying avenues for ice sheet change. In West Antarctica, we find a new deep connection between the coast and interior basin running through the heart of the Marie Byrd Land subglacial massif, with associated deep erosional scars with implications for the history of the West Antarctic ice sheet. In eastern Wilkes Land, deep, comparably recently active eroding troughs dominate the hydrology of the Wilkes Subglacial Basin. In western Wilkes Land in East Antarctica, (as noted by other presentations in this session) fjord systems nucleating on continental suture zones indicate the extent of paleoice sheet margins, and act as switches for modern subglacial hydrology.

Advanced Sulfur Cathode Enabled by Highly Crumpled Nitrogen-Doped Graphene Sheets for High-Energy-Density Lithium-Sulfur Batteries.

PubMed

Song, Jiangxuan; Yu, Zhaoxin; Gordin, Mikhail L; Wang, Donghai

2016-02-10

Herein, we report a synthesis of highly crumpled nitrogen-doped graphene sheets with ultrahigh pore volume (5.4 cm(3)/g) via a simple thermally induced expansion strategy in absence of any templates. The wrinkled graphene sheets are interwoven rather than stacked, enabling rich nitrogen-containing active sites. Benefiting from the unique pore structure and nitrogen-doping induced strong polysulfide adsorption ability, lithium-sulfur battery cells using these wrinkled graphene sheets as both sulfur host and interlayer achieved a high capacity of ∼1000 mAh/g and exceptional cycling stability even at high sulfur content (≥80 wt %) and sulfur loading (5 mg sulfur/cm(2)). The high specific capacity together with the high sulfur loading push the areal capacity of sulfur cathodes to ∼5 mAh/cm(2), which is outstanding compared to other recently developed sulfur cathodes and ideal for practical applications.

The Complexity of Folding Self-Folding Origami

NASA Astrophysics Data System (ADS)

Stern, Menachem; Pinson, Matthew B.; Murugan, Arvind

2017-10-01

Why is it difficult to refold a previously folded sheet of paper? We show that even crease patterns with only one designed folding motion inevitably contain an exponential number of "distractor" folding branches accessible from a bifurcation at the flat state. Consequently, refolding a sheet requires finding the ground state in a glassy energy landscape with an exponential number of other attractors of higher energy, much like in models of protein folding (Levinthal's paradox) and other NP-hard satisfiability (SAT) problems. As in these problems, we find that refolding a sheet requires actuation at multiple carefully chosen creases. We show that seeding successful folding in this way can be understood in terms of subpatterns that fold when cut out ("folding islands"). Besides providing guidelines for the placement of active hinges in origami applications, our results point to fundamental limits on the programmability of energy landscapes in sheets.

High export of dissolved silica from the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Meire, L.; Meire, P.; Struyf, E.; Krawczyk, D. W.; Arendt, K. E.; Yde, J. C.; Juul Pedersen, T.; Hopwood, M. J.; Rysgaard, S.; Meysman, F. J. R.

2016-09-01

Silica is an essential element for marine life and plays a key role in the biogeochemistry of the ocean. Glacial activity stimulates rock weathering, generating dissolved silica that is exported to coastal areas along with meltwater. The magnitude of the dissolved silica export from large glacial areas such as the Greenland Ice Sheet is presently poorly quantified and not accounted for in global budgets. Here we present data from two fjord systems adjacent to the Greenland Ice Sheet which reveal a large export of dissolved silica by glacial meltwater relative to other macronutrients. Upscaled to the entire Greenland Ice Sheet, the export of dissolved silica equals 22 ± 10 Gmol Si yr-1. When the silicate-rich meltwater mixes with upwelled deep water, either inside or outside Greenland's fjords, primary production takes place at increased silicate to nitrate ratios. This likely stimulates the growth of diatoms relative to other phytoplankton groups.

The use of platelet-rich fibrin combined with periodontal ligament and jaw bone mesenchymal stem cell sheets for periodontal tissue engineering.

PubMed

Wang, Zhong-Shan; Feng, Zhi-Hong; Wu, Guo-Feng; Bai, Shi-Zhu; Dong, Yan; Chen, Fa-Ming; Zhao, Yi-Min

2016-06-21

Periodontal regeneration involves the restoration of at least three unique tissues: cementum, periodontal ligament tissue (PDL) and alveolar bone tissue. Here, we first isolated human PDL stem cells (PDLSCs) and jaw bone mesenchymal stem cells (JBMSCs). These cells were then induced to form cell sheets using an ascorbic acid-rich approach, and the cell sheet properties, including morphology, thickness and gene expression profile, were compared. Platelet-rich fibrin (PRF) derived from human venous blood was then fabricated into bioabsorbable fibrin scaffolds containing various growth factors. Finally, the in vivo potential of a cell-material construct based on PDLSC sheets, PRF scaffolds and JBMSC sheets to form periodontal tissue was assessed in a nude mouse model. In this model, PDLSC sheet/PRF/JBMSC sheet composites were placed in a simulated periodontal space comprising human treated dentin matrix (TDM) and hydroxyapatite (HA)/tricalcium phosphate (TCP) frameworks. Eight weeks after implantation, the PDLSC sheets tended to develop into PDL-like tissues, while the JBMSC sheets tended to produce predominantly bone-like tissues. In addition, the PDLSC sheet/PRF/JBMSC sheet composites generated periodontal tissue-like structures containing PDL- and bone-like tissues. Further improvements in this cell transplantation design may have the potential to provide an effective approach for future periodontal tissue regeneration.

The Steady Flow Resistance of Perforated Sheet Materials in High Speed Grazing Flows

NASA Technical Reports Server (NTRS)

Syed, Asif A.; Yu, Jia; Kwan, H. W.; Chien, E.; Jones, Michael G. (Technical Monitor)

2002-01-01

A study was conducted to determine the effects of high speed grazing air flow on the acoustic resistance of perforated sheet materials used in the construction of acoustically absorptive liners placed in commercial aircraft engine nacelles. Since DC flow resistance of porous sheet materials is known to be a major component of the acoustic resistance of sound suppression liners, the DC flow resistance of a set of perforated face-sheets and linear 'wiremesh' face-sheets was measured in a flow duct apparatus (up to Mach 0.8). Samples were fabricated to cover typical variations in perforated face-sheet parameters, such as hole diameter, porosity and sheet thickness, as well as those due to different manufacturing processes. The DC flow resistance data from perforated sheets were found to correlate strongly with the grazing flow Mach number and the face-sheet porosity. The data also show correlation against the boundary layer displacement thickness to hole-diameter ratio. The increase in resistance with grazing flow for punched aluminum sheets is in good agreement with published results up to Mach 0.4, but is significantly larger than expected above Mach 0.4. Finally, the tests demonstrated that there is a significant increase in the resistance of linear 'wiremesh' type face-sheet materials.

Non-Evolutionarity of a Reconnecting Current Sheet as a Cause of Its Splitting into MHD Shocks

NASA Astrophysics Data System (ADS)

Markovsky, S. A.; Somov, B. V.

1995-04-01

Numerical simulations of the magnetic reconnection process in a current sheet show that, in some cases, MHD shocks appear to be attached to edges of the sheet. The appearance of the shocks may be considered to be a result of splitting of the sheet. In the present paper we suppose that this splitting takes place in consequence of non-evolutionarity of the reconnecting current sheet as a discontinuity. The problem of time evolution of small perturbations does not have a unique solution for a non-evolutionary discontinuity, and it splits into other (evolutionary) discontinuities. Such an approach allows us to determine conditions under which the splitting of the-sheet occurs. The main difficulty of this approach is that a current sheet is not reduced to a classified 1D discontinuity, because inhomogeneity of flow velocity inside the sheet is two-dimensional. To formulate the non-evolutionarity problem, we solve the linear MHD equations inside and outside the sheet and deduce linearized 1D boundary conditions at its surface. We show that for large enough conductivity, small perturbations exist which interact with the sheet as with a discontinuity. Then we obtain a non-evolutionarity criterion, with respect to these perturbations, in the form of a restriction on the flow velocity across the surface of the sheet.

Newly Developed Biocompatible Material: Dispersible Titanium-Doped Hydroxyapatite Nanoparticles Suitable for Antibacterial Coating on Intravascular Catheters.

PubMed

Furuzono, Tsutomu; Okazaki, Masatoshi; Azuma, Yoshinao; Iwasaki, Mitsunobu; Kogai, Yasumichi; Sawa, Yoshiki

2017-01-01

Thirteen patients with chlorhexidine-silver sulfadiazine-impregnated catheters have experienced serious anaphylactic shock in Japan. These adverse reactions highlight the lack of commercially available catheters impregnated with strong antibacterial chemical agents. A system should be developed that can control both biocompatibility and antibacterial activity. Hydroxyapatite (HAp) is biocompatible with bone and skin tissues. To provide antibacterial activity by using an external physical stimulus, titanium (Ti) ions were doped into the HAp structure. Highly dispersible, Ti-doped HAp (Ti-HAp) nanoparticles suitable as a coating material were developed. In 3 kinds of Ti-HAp [Ti/(Ca + Ti) = 0.05, 0.1, 0.2], the Ti content in the HAp was approximately 70% of that used in the Ti-HAp preparation, as determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). ICP-AES and X-ray diffraction showed Ti ions were well substituted into the HAp lattice. The nanoparticles were almost uniformly coated on a polyethylene (PE) sheet in a near-monolayer with a surface coverage ratio >95%. The antibacterial activity of the Ti-HAp nanoparticles containing 7.3% Ti ions and coating the sheet was evaluated by calculating the survival ratio of Pseudomonas aeruginosa on the coated sheet after ultraviolet (UV) irradiation. The Ti-HAp-coated sheet showed a 50% decrease in the number of P. aeruginosa compared with that on an uncoated control PE sheet after UV irradiation for 30 s. Key Messages: A system of biocompatibility and antibacterial activity with an on/off switch controlled by external UV stimulation was developed. The system is expected to be applicable in long-term implanted intravascular catheters. © 2017 S. Karger AG, Basel.

Evidence for a palaeo-subglacial lake on the Antarctic continental shelf

PubMed Central

Kuhn, Gerhard; Hillenbrand, Claus-Dieter; Kasten, Sabine; Smith, James A.; Nitsche, Frank O.; Frederichs, Thomas; Wiers, Steffen; Ehrmann, Werner; Klages, Johann P.; Mogollón, José M.

2017-01-01

Subglacial lakes are widespread beneath the Antarctic Ice Sheet but their control on ice-sheet dynamics and their ability to harbour life remain poorly characterized. Here we present evidence for a palaeo-subglacial lake on the Antarctic continental shelf. A distinct sediment facies recovered from a bedrock basin in Pine Island Bay indicates deposition within a low-energy lake environment. Diffusive-advection modelling demonstrates that low chloride concentrations in the pore water of the corresponding sediments can only be explained by initial deposition of this facies in a freshwater setting. These observations indicate that an active subglacial meltwater network, similar to that observed beneath the extant ice sheet, was also active during the last glacial period. It also provides a new framework for refining the exploration of these unique environments. PMID:28569750

12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the face...

12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the face...

19 CFR 123.23 - Train sheet for in-transit rail shipments.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 1 2011-04-01 2011-04-01 false Train sheet for in-transit rail shipments. 123.23 Section 123.23 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY... at the port of exit a train sheet, sometimes called a consist, bridge sheet or trip sheet, listing...

Machine Shop Suggested Job and Task Sheets. Part I. 25 Elementary Jobs.

ERIC Educational Resources Information Center

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of elementary job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-five simple machine shop job sheets are included. Some or all of this material is provided for each job sheet: an introductory sheet with aim, checking…

Fact Sheets from the ERIC Clearinghouse on Handicapped and Gifted Children, 1980.

ERIC Educational Resources Information Center

ERIC Clearinghouse on Handicapped and Gifted Children, Reston, VA.

The document is a compilation of 15 fact sheets developed during 1980 by the ERIC Clearinghouse on Handicapped and Gifted Children. Fact sheets are single sheets which provide basic information in a question-answer format and include additional resources and references. The fact sheets have the following titles: "Sex Education for Retarded…

Holocene reworking of a sand sheet in the Merrimack Embayment, Western Gulf of Maine

USGS Publications Warehouse

Hein, C.J.; FitzGerald, D.M.; Barnhardt, W.

2007-01-01

Recent bathymetric, backscatter, and seafloor sediment samples demonstrate that a large sand sheet was formed in the inner shelf by the reworking of the Merrimack River lowstand delta (deposited 12 kya; currently at 45 m depth) and braid plain during the Holocene transgression. Asymmetric bedforms and distinct grain size distributions suggest the sand sheet is actively being reworked by inner-shelf processes. Bottom sediments range from silty sand at the submerged delta to coarse sand and fine gravel in the innermost shelf (depth: 10-50 m). Coarse-grained sand comprises an expansive (32 km2 ) featureless sand sheet centered off the Merrimack River. Fine-grained sand discontinuously overlies this sand sheet in many locations and forms long wavelength (100 – 800 m), low amplitude (1-2 m), asymmetrical bedforms. Sets of these bedforms are oriented from slightly oblique offshore to onshore; several bedform sets are located within 1 km and oriented orthogonally to one another. Along the paleo-delta front north-northwest oriented bedforms are dominant. Inshore of these features, the bedforms become more closely spaced and have orientations to the west and westsouthwest. Preliminary data suggest that the combined forcings of instantaneous storm-wave generated shear stress and storm-induced currents associated with high energy northeast storm events may be responsible for sand sheet reworking and bedform development.

Orientation determination of interfacial beta-sheet structures in situ.

PubMed

Nguyen, Khoi Tan; King, John Thomas; Chen, Zhan

2010-07-01

Structural information such as orientations of interfacial proteins and peptides is important for understanding properties and functions of such biological molecules, which play crucial roles in biological applications and processes such as antimicrobial selectivity, membrane protein activity, biocompatibility, and biosensing performance. The alpha-helical and beta-sheet structures are the most widely encountered secondary structures in peptides and proteins. In this paper, for the first time, a method to quantify the orientation of the interfacial beta-sheet structure using a combined attenuated total reflectance Fourier transformation infrared spectroscopic (ATR-FTIR) and sum frequency generation (SFG) vibrational spectroscopic study was developed. As an illustration of the methodology, the orientation of tachyplesin I, a 17 amino acid peptide with an antiparallel beta-sheet, adsorbed to polymer surfaces as well as associated with a lipid bilayer was determined using the regular and chiral SFG spectra, together with polarized ATR-FTIR amide I signals. Both the tilt angle (theta) and the twist angle (psi) of the beta-sheet at interfaces are determined. The developed method in this paper can be used to obtain in situ structural information of beta-sheet components in complex molecules. The combination of this method and the existing methodology that is currently used to investigate alpha-helical structures will greatly broaden the application of optical spectroscopy in physical chemistry, biochemistry, biophysics, and structural biology.

Thin current sheets observation by MMS during a near-Earth's magnetotail reconnection event

NASA Astrophysics Data System (ADS)

Nakamura, R.; Varsani, A.; Nakamura, T.; Genestreti, K.; Plaschke, F.; Baumjohann, W.; Nagai, T.; Burch, J.; Cohen, I. J.; Ergun, R.; Fuselier, S. A.; Giles, B. L.; Le Contel, O.; Lindqvist, P. A.; Magnes, W.; Schwartz, S. J.; Strangeway, R. J.; Torbert, R. B.

2017-12-01

During summer 2017, the four spacecraft of the Magnetospheric Multiscale (MMS) mission traversed the nightside magnetotail current sheet at an apogee of 25 RE. They detected a number of flow reversal events suggestive of the passage of the reconnection current sheet. Due to the mission's unprecedented high-time resolution and spatial separation well below the ion scales, structure of thin current sheets is well resolved both with plasma and field measurements. In this study we examine the detailed structure of thin current sheets during a flow reversal event from tailward flow to Earthward flow, when MMS crossed the center of the current sheet . We investigate the changes in the structure of the thin current sheet relative to the X-point based on multi-point analysis. We determine the motion and strength of the current sheet from curlometer calculations comparing these with currents obtained from the particle data. The observed structures of these current sheets are also compared with simulations.

Stacked endoplasmic reticulum sheets are connected by helicoidal membrane motifs.

PubMed

Terasaki, Mark; Shemesh, Tom; Kasthuri, Narayanan; Klemm, Robin W; Schalek, Richard; Hayworth, Kenneth J; Hand, Arthur R; Yankova, Maya; Huber, Greg; Lichtman, Jeff W; Rapoport, Tom A; Kozlov, Michael M

2013-07-18

The endoplasmic reticulum (ER) often forms stacked membrane sheets, an arrangement that is likely required to accommodate a maximum of membrane-bound polysomes for secretory protein synthesis. How sheets are stacked is unknown. Here, we used improved staining and automated ultrathin sectioning electron microscopy methods to analyze stacked ER sheets in neuronal cells and secretory salivary gland cells of mice. Our results show that stacked ER sheets form a continuous membrane system in which the sheets are connected by twisted membrane surfaces with helical edges of left- or right-handedness. The three-dimensional structure of tightly stacked ER sheets resembles a parking garage, in which the different levels are connected by helicoidal ramps. A theoretical model explains the experimental observations and indicates that the structure corresponds to a minimum of elastic energy of sheet edges and surfaces. The structure allows the dense packing of ER sheets in the restricted space of a cell. Copyright © 2013 Elsevier Inc. All rights reserved.

Wrapping a liquid drop with a thin elastic sheet

NASA Astrophysics Data System (ADS)

Paulsen, Joseph; Démery, Vincent; Davidovitch, Benny; Santangelo, Chris; Russell, Thomas; Menon, Narayanan

2014-11-01

We study the wrapping of a liquid drop by an initially-planar ultrathin (~ 100 nm) circular sheet. These elastic sheets can completely relax compressive stresses by forming wrinkles. In the experiment, we find that when a small fraction of the drop is covered, the overall shape of the sheet (i.e. averaging over the wrinkles) is axisymmetric. As we shrink the drop further, the sheet develops radial folds that break the axisymmetry of the sheet and the drop. Our data are consistent with a model where the sheet selects the shape that minimizes the exposed liquid surface area. We thus identify a ``geometric wrapping'' regime, where the partially-wrapped shape depends only on the relative radii of the sheet and the drop; the global breaking of axisymmetry is independent of the elastic energy of the deformed sheet. This regime requires that bending energy is negligible compared to surface energy, in contrast to the ``capillary origami'' regime where the static shape of the drop comes from a balance of bending and capillary forces.

Conceptual models of the evolution of transgressive dune field systems

NASA Astrophysics Data System (ADS)

A. Hesp, Patrick

2013-10-01

This paper examines the evolutionary paths of some transgressive dune fields that have formed on different coasts of the world, and presents some initial conceptual models of system dynamics for transgressive dune sheets and dune fields. Various evolutionary pathways are conceptualized based on a visual examination of dune fields from around the world. On coasts with high sediment supply, dune sheets and dune fields tend to accumulate as large scale barrier systems with little colonization of vegetation in arid-hyper to arid climate regimes, and as multiple, active discrete phases of dune field and deflation plain couplets in temperate to tropical environments. Active dune fields tend to be singular entities on coasts with low to moderate sediment supply. Landscape complexity and vegetation richness and diversity increases as dune fields evolve from simple active sheets and dunes to single and multiple deflation plains and basins, precipitation ridges, nebkha fields and a host of other dune types associated with vegetation (e.g. trailing ridges, slacks, remnant knobs, gegenwalle ridges and dune track ridges, ‘tree islands' and ‘bush pockets'). Three principal scenarios of transgressive dune sheet and dune field development are discussed, including dune sheets or dune fields evolving directly from the backshore, development following foredune and/or dune field erosion, and development from the breakdown or merging of parabolic dunes. Various stages of evolution are outlined for each scenario. Knowledge of evolutionary patterns and stages in coastal dune fields is very limited and caution is urged in attempts to reverse, change and/or modify dune fields to ‘restore' some perceived loss of ecosystem or dune functioning.

Conceptual models of the evolution of transgressive dune field systems

NASA Astrophysics Data System (ADS)

Hesp, Patrick A.

2013-10-01

This paper examines the evolutionary paths of some transgressive dune fields that have formed on different coasts of the world, and presents some initial conceptual models of system dynamics for transgressive dune sheets and dune fields. Various evolutionary pathways are conceptualized based on a visual examination of dune fields from around the world. On coasts with high sediment supply, dune sheets and dune fields tend to accumulate as large scale barrier systems with little colonization of vegetation in arid-hyper to arid climate regimes, and as multiple, active discrete phases of dune field and deflation plain couplets in temperate to tropical environments. Active dune fields tend to be singular entities on coasts with low to moderate sediment supply. Landscape complexity and vegetation richness and diversity increases as dune fields evolve from simple active sheets and dunes to single and multiple deflation plains and basins, precipitation ridges, nebkha fields and a host of other dune types associated with vegetation (e.g. trailing ridges, slacks, remnant knobs, gegenwalle ridges and dune track ridges, 'tree islands' and 'bush pockets'). Three principal scenarios of transgressive dune sheet and dune field development are discussed, including dune sheets or dune fields evolving directly from the backshore, development following foredune and/or dune field erosion, and development from the breakdown or merging of parabolic dunes. Various stages of evolution are outlined for each scenario. Knowledge of evolutionary patterns and stages in coastal dune fields is very limited and caution is urged in attempts to reverse, change and/or modify dune fields to 'restore' some perceived loss of ecosystem or dune functioning.

71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLEARCHED DAM: STRESS SHEET, SHEET ...

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

71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLE-ARCHED DAM: STRESS SHEET, SHEET 3; DECEMBER 20, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

Thermomechanical processing of HAYNES alloy No. 188 sheet to improve creep strength

NASA Technical Reports Server (NTRS)

Klarstrom, D. L.

1978-01-01

Improvements in the low strain creep strength of HAYNES alloy No. 188 thin gauge sheet by means of thermomechanical processing were developed. Processing methods designed to develop a sheet with strong crystallographic texture after recrystallization and to optimize grain size were principally studied. The effects of thickness-to-grain diameter ratio and prestrain on low strain creep strength were also briefly examined. Results indicate that the most significant improvements were obtained in the sheets having a strong crystallographic texture. The low strain creep strength of the textured sheets was observed to be superior to that of standard production sheets in the 922 K to 1255 K temperature range. Tensile, stress rupture, fabricability, and surface stability properties of the experimental sheets were also measured and compared to property values reported for the baseline production sheets.

Determining Beta Sheet Crystallinity in Fibrous Proteins by Thermal Analysis and Infrared Spectroscopy

NASA Astrophysics Data System (ADS)

Hu, Xiao; Kaplan, David; Cebe, Peggy

2007-03-01

We report a study of self-assembled beta pleated sheets in Bombyx mori silk fibroin films using thermal analysis and infrared spectroscopy. Crystallization of beta pleated sheets was effected either by heating the films above the glass transition temperature (Tg) and holding isothermally, or by exposure to methanol. The fractions of secondary structural components including random coils, alpha helices, beta pleated sheets, turns, and side chains, were evaluated using Fourier self-deconvolution (FSD) of the infrared absorbance spectra. As crystalline beta sheets form, the heat capacity increment from the TMDSC trace at Tg is systematically decreased and is linearly well correlated with beta sheet content determined from FSD. This analysis of beta sheet content can serve as an alternative to X-ray methods and may have wide applicability to other crystalline beta sheet forming proteins.

Flat-plate solar array project. Volume 3: Silicon sheet: Wafers and ribbons

NASA Technical Reports Server (NTRS)

Briglio, A.; Dumas, K.; Leipold, M.; Morrison, A.

1986-01-01

The primary objective of the Silicon Sheet Task of the Flat-Plate Solar Array (FSA) Project was the development of one or more low cost technologies for producing silicon sheet suitable for processing into cost-competitive solar cells. Silicon sheet refers to high purity crystalline silicon of size and thickness for fabrication into solar cells. Areas covered in the project were ingot growth and casting, wafering, ribbon growth, and other sheet technologies. The task made and fostered significant improvements in silicon sheet including processing of both ingot and ribbon technologies. An additional important outcome was the vastly improved understanding of the characteristics associated with high quality sheet, and the control of the parameters required for higher efficiency solar cells. Although significant sheet cost reductions were made, the technology advancements required to meet the task cost goals were not achieved.

Improving Climate Literacy Using The Ice Sheet System Model (ISSM): A Prototype Virtual Ice Sheet Laboratory For Use In K-12 Classrooms

NASA Astrophysics Data System (ADS)

Halkides, D. J.; Larour, E. Y.; Perez, G.; Petrie, K.; Nguyen, L.

2013-12-01

Statistics indicate that most Americans learn what they will know about science within the confines of our public K-12 education system and the media. Next Generation Science Standards (NGSS) aim to remedy science illiteracy and provide guidelines to exceed the Common Core State Standards that most U.S. state governments have adopted, by integrating disciplinary cores with crosscutting ideas and real life practices. In this vein, we present a prototype ';Virtual Ice Sheet Laboratory' (I-Lab), geared to K-12 students, educators and interested members of the general public. I-Lab will allow users to perform experiments using a state-of-the-art dynamical ice sheet model and provide detailed downloadable lesson plans, which incorporate this model and are consistent with NGSS Physical Science criteria for different grade bands (K-2, 3-5, 6-8, and 9-12). The ultimate goal of this website is to improve public climate science literacy, especially in regards to the crucial role of the polar ice sheets in Earth's climate and sea level. The model used will be the Ice Sheet System Model (ISSM), an ice flow model developed at NASA's Jet Propulsion Laboratory and UC Irvine, that simulates the near-term evolution of polar ice sheets (Greenland and Antarctica) and includes high spatial resolution capabilities and data assimilation to produce realistic simulations of ice sheet dynamics at the continental scale. Open sourced since 2011, ISSM is used in cutting edge cryosphere research around the globe. Thru I-Lab, students will be able to access ISSM using a simple, online graphical interface that can be launched from a web browser on a computer, tablet or smart phone. The interface will allow users to select different climate conditions and watch how the polar ice sheets evolve in time under those conditions. Lesson contents will include links to background material and activities that teach observation recording, concept articulation, hypothesis formulation and testing, and critical problem solving appropriate to grade level.

Microchannel laminated mass exchanger and method of making

DOEpatents

Martin, Peter M [Kennewick, WA; Bennett, Wendy D [Kennewick, WA; Matson, Dean W [Kennewick, WA; Stewart, Donald C [Richland, WA; Drost, Monte K [Pasco, WA; Wegeng, Robert S [Richland, WA; Perez, Joseph M [Richland, WA; Feng, Xiangdong [West Richland, WA; Liu, Jun [West Richland, WA

2003-03-18

The present invention is a microchannel mass exchanger having a first plurality of inner thin sheets and a second plurality of outer thin sheets. The inner thin sheets each have a solid margin around a circumference, the solid margin defining a slot through the inner thin sheet thickness. The outer thin sheets each have at least two header holes on opposite ends and when sandwiching an inner thin sheet. The outer thin sheets further have a mass exchange medium. The assembly forms a closed flow channel assembly wherein fluid enters through one of the header holes into the slot and exits through another of the header holes after contacting the mass exchange medium.

Microchannel laminated mass exchanger and method of making

DOEpatents

Martin, Peter M.; Bennett, Wendy D.; Matson, Dean W.; Stewart, Donald C.; Drost, Monte K.; Wegeng, Robert S.; Perez, Joseph M.; Feng, Xiangdong; Liu, Jun

2000-01-01

The present invention is a microchannel mass exchanger having a first plurality of inner thin sheets and a second plurality of outer thin sheets. The inner thin sheets each have a solid margin around a circumference, the solid margin defining a slot through the inner thin sheet thickness. The outer thin sheets each have at least two header holes on opposite ends and when sandwiching an inner thin sheet. The outer thin sheets further have a mass exchange medium. The assembly forms a closed flow channel assembly wherein fluid enters through one of the header holes into the slot and exits through another of the header holes after contacting the mass exchange medium.

Microchannel laminated mass exchanger and method of making

DOEpatents

Martin, Peter M [Kennewick, WA; Bennett, Wendy D [Kennewick, WA; Matson, Dean W [Kennewick, WA; Stewart, Donald C [Richland, WA; Drost, Monte K [Pasco, WA; Wegeng, Robert S [Richland, WA; Perez, Joseph M [Richland, WA; Feng, Xiangdong [West Richland, WA; Liu, Jun [West Richland, WA

2002-03-05

The present invention is a microchannel mass exchanger having a first plurality of inner thin sheets and a second plurality of outer thin sheets. The inner thin sheets each have a solid margin around a circumference, the solid margin defining a slot through the inner thin sheet thickness. The outer thin sheets each have at least two header holes on opposite ends and when sandwiching an inner thin sheet. The outer thin sheets further have a mass exchange medium. The assembly forms a closed flow channel assembly wherein fluid enters through one of the header holes into the slot and exits through another of the header holes after contacting the mass exchange medium.

Protein unfolding versus β-sheet separation in spider silk nanocrystals

NASA Astrophysics Data System (ADS)

Alam, Parvez

2014-03-01

In this communication a mechanism for spider silk strain hardening is proposed. Shear failure of β-sheet nanocrystals is the first failure mode that gives rise to the creation of smaller nanocrystals, which are of higher strength and stiffness. β-sheet unfolding requires more energy than nanocrystal separation in a shear mode of failure. As a result, unfolding occurs after the nanocrystals separate in shear. β-sheet unfolding yields a secondary strain hardening effect once the β-sheet conformation is geometrically stable and acts like a unidirectional fibre in a fibre reinforced composite. The mechanism suggested herein is based on molecular dynamics calculations of residual inter-β-sheet separation strengths against residual intra-β-sheet unfolding strengths.

Sheet production apparatus for removing a crystalline sheet from the surface of a melt using gas jets located above and below the crystalline sheet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kellerman, Peter L.; Thronson, Gregory D.

In one embodiment, a sheet production apparatus comprises a vessel configured to hold a melt of a material. A cooling plate is disposed proximate the melt and is configured to form a sheet of the material on the melt. A first gas jet is configured to direct a gas toward an edge of the vessel. A sheet of a material is translated horizontally on a surface of the melt and the sheet is removed from the melt. The first gas jet may be directed at the meniscus and may stabilize this meniscus or increase local pressure within the meniscus.

47 CFR 32.103 - Balance sheet accounts for other than regulated-fixed assets to be maintained.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Balance sheet accounts for other than regulated... for Balance Sheet Accounts § 32.103 Balance sheet accounts for other than regulated-fixed assets to be maintained. Balance sheet accounts to be maintained by Class A and Class B telephone companies for other than...

47 CFR 32.103 - Balance sheet accounts for other than regulated-fixed assets to be maintained.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Balance sheet accounts for other than regulated... for Balance Sheet Accounts § 32.103 Balance sheet accounts for other than regulated-fixed assets to be maintained. Balance sheet accounts to be maintained by Class A and Class B telephone companies for other than...

78 FR 14270 - Stainless Steel Sheet and Strip in Coils From Mexico: Notice of Settlement of NAFTA Proceedings

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-05

... DEPARTMENT OF COMMERCE International Trade Administration [A-201-822] Stainless Steel Sheet and... stainless steel sheet and strip in coils from Mexico (SSSS from Mexico). See Stainless Steel Sheet and Strip..., 2010, as a result of a sunset review. See Stainless Steel Sheet and Strip in Coils from Germany, Italy...

Predicting pulsar scintillation from refractive plasma sheets

NASA Astrophysics Data System (ADS)

Simard, Dana; Pen, Ue-Li

2018-07-01

The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along sheets in the ionized interstellar medium, such as those due to Alfvén waves propagating along current sheets. If these sheets are closely aligned to our line of sight to the pulsar, high bending angles arise at the wave crests and a selection effect causes alignment of images produced at different crests, similar to grazing reflection off of a lake. Using geometric optics, we develop a simple parametrized model of these corrugated sheets that can be constrained with a single observation and that makes observable predictions for variations in the scintillation of the pulsar over time and frequency. This model reveals qualitative differences between lensing from overdense and underdense corrugated sheets: only if the sheet is overdense compared to the surrounding interstellar medium can the lensed images be brighter than the line-of-sight image to the pulsar, and the faint lensed images are closer to the pulsar at higher frequencies if the sheet is underdense, but at lower frequencies if the sheet is overdense.

Do You Prefer to Have the Text or a Sheet with Your Physics Exams?

NASA Astrophysics Data System (ADS)

Hamed, Kastro M.

2008-05-01

Many high school and introductory college physics instructors ponder the choice between "open text" exams versus "facts and formulae sheet" exams. Other alternatives are closed book/closed notes exams or an instructor-prepared sheet of facts and relevant formulas. There is no agreement on merit. Rehfuss strongly opposes allowing students to use formula sheets while taking physics exams despite acknowledging that such use is common practice. Cone2 responded to Rehfuss by defending the use of such sheets and outlining the benefits of a "cheat sheet." Debate over the use of a "cheat sheet" or other resources during exams is not limited to the physics community. Skidmore and Aagaard3 studied the relationship between testing conditions and student test scores for students in teacher education. Two decades earlier Boniface,4 Dorsal and Cundiff,5 and Hindman6 published papers on the use of texts and/or sheets during examinations in psychology and education. Others, such as Pullen et al.7 focused on studying the discarded cheat sheets themselves. Humorously, in October 2005 The New York Times8 reported an unusual museum exhibit of "cheat sheets" and the different ways students had cheated at a particular university.

A comparison of coronal and interplanetary current sheet inclinations

NASA Technical Reports Server (NTRS)

Behannon, K. W.; Burlaga, L. F.; Hundhausen, A. J.

1983-01-01

The HAO white light K-coronameter observations show that the inclination of the heliospheric current sheet at the base of the corona can be both large (nearly vertical with respect to the solar equator) or small during Cararington rotations 1660 - 1666 and even on a single solar rotation. Voyager 1 and 2 magnetic field observations of crossing of the heliospheric current sheet at distances from the Sun of 1.4 and 2.8 AU. Two cases are considered, one in which the corresponding coronameter data indicate a nearly vertical (north-south) current sheet and another in which a nearly horizontal, near equatorial current sheet is indicated. For the crossings of the vertical current sheet, a variance analysis based on hour averages of the magnetic field data gave a minimum variance direction consistent with a steep inclination. The horizontal current sheet was observed by Voyager as a region of mixed polarity and low speeds lasting several days, consistent with multiple crossings of a horizontal but irregular and fluctuating current sheet at 1.4 AU. However, variance analysis of individual current sheet crossings in this interval using 1.92 see averages did not give minimum variance directions consistent with a horizontal current sheet.

Predicting Pulsar Scintillation from Refractive Plasma Sheets

NASA Astrophysics Data System (ADS)

Simard, Dana; Pen, Ue-Li

2018-05-01

The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along sheets in the ionized interstellar medium, such as those due to Alfvén waves propagating along current sheets. If these sheets are closely aligned to our line-of-sight to the pulsar, high bending angles arise at the wave crests and a selection effect causes alignment of images produced at different crests, similar to grazing reflection off of a lake. Using geometric optics, we develop a simple parameterized model of these corrugated sheets that can be constrained with a single observation and that makes observable predictions for variations in the scintillation of the pulsar over time and frequency. This model reveals qualitative differences between lensing from overdense and underdense corrugated sheets: Only if the sheet is overdense compared to the surrounding interstellar medium can the lensed images be brighter than the line-of-sight image to the pulsar, and the faint lensed images are closer to the pulsar at higher frequencies if the sheet is underdense, but at lower frequencies if the sheet is overdense.

High-performance transparent and stretchable all-solid supercapacitors based on highly aligned carbon nanotube sheets

PubMed Central

Chen, Tao; Peng, Huisheng; Durstock, Michael; Dai, Liming

2014-01-01

By using highly aligned carbon nanotube (CNT) sheets of excellent optical transmittance and mechanical stretchability as both the current collector and active electrode, high-performance transparent and stretchable all-solid supercapacitors with a good stability were developed. A transmittance up to 75% at the wavelength of 550 nm was achieved for a supercapacitor made from a cross-over assembly of two single-layer CNT sheets. The transparent supercapacitor has a specific capacitance of 7.3 F g−1 and can be biaxially stretched up to 30% strain without any obvious change in electrochemical performance even over hundreds stretching cycles. PMID:24402400

Non Profit and For-Profit Higher Education Accreditation. Council for Higher Education Accreditation. Fact Sheet #7

ERIC Educational Resources Information Center

Council for Higher Education Accreditation, 2012

2012-01-01

This fact sheet presents data provided to the Council for Higher Education Accreditation (CHEA) by accrediting organizations for accrediting activity during 2010-2011. It includes both Title IV and Non-Title IV institutions. Data are presented in the following categories: (1) Accrediting Organizations; (2) Fourteen Major For-Profit Higher…

Participation in Sports and Civic Engagement. Fact Sheet

ERIC Educational Resources Information Center

Lopez, Mark Hugo; Moore, Kimberlee

2006-01-01

One reason to offer sports in school is to teach youth the values, skills, and habits that will make them more active, engaged, and responsible citizens. Past evidence on the civic effects of sports is mixed, but points to some potential positive civic effects. This fact sheet uses recent data from the 2002 National Youth Survey of Civic…

Exploring Parenting: Information Sheets for Parents = Explorando El Arte de Ser Padres: Hojas informativas para los padres.

ERIC Educational Resources Information Center

Administration for Children, Youth, and Families (DHHS), Washington, DC. Head Start Bureau.

This document, provided here in separate English and Spanish versions, is a collection of informational and instructional sheets for parents of young children, divided into 20 thematic sections. Each of the sections includes information on the topic area, some learning activities, and questions for discussion. The sessions are: (1) "Getting…

Financing Solar Installations with New Markets Tax Credits: Denver, Colorado (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coughlin, J.

Fact sheet provides a brief overview of New Markets Tax Credits (NMTCs), a third-party financing incentive for solar installations in the public sector. NMTCs are intended to encourage economic activity in low-income and disadvantaged neighborhoods. The use of NMTCs in an innovative solar project transaction by the City of Denver, Colorado, is highlighted.

Fuels planning: science synthesis and integration; environmental consequences fact sheet 08: Evaluating sedimentation risks associated with fuel management

Treesearch

William Elliot; Pete Robichaud

2005-01-01

This fact sheet describes the sources of sediment in upland forest watersheds in the context of fuel management activities. It presents the dominant forest soil erosion processes, and the principles behind the new sediment delivery interface developed to aid in erosion analysis of fuel management projects.

Know Your School District: Tips for Parents. PACER Center ACTion Information Sheets. PHP-c112

ERIC Educational Resources Information Center

PACER Center, 2006

2006-01-01

Becoming familiar with the school district will help parents become active and involved partners in their child's education. Research has demonstrated that family involvement in children's education can boost their academic success. Knowing about the following areas, which are discussed in this information sheet, can help parental involvement at…

"Gulliver's Travels" by Alfred Silver with Music by Stephen Naylor. Cue Sheet for Students.

ERIC Educational Resources Information Center

Waterfall, Milde; Flynn, Rosalind, Ed.

Designed to be used before and after attending a musical adaptation of Jonathan's Swift's "Gulliver's Travels" (performed by the Mermaid Theatre of Nova Scotia), this cue sheet presents information about the performance and suggests activities that can be done with classmates, friends, or family members. Beginning with an illustration of…

Supplying osteogenesis to dead bone using an osteogenic matrix cell sheet.

PubMed

Uchihara, Yoshinobu; Akahane, Manabu; Okuda, Akinori; Shimizu, Takamasa; Masuda, Keisuke; Kira, Tsutomu; Kawate, Kenji; Tanaka, Yasuhito

2018-02-22

To evaluate whether osteogenic matrix cell sheets can supply osteogenesis to dead bone. Femur bone fragments (5 mm in length) were obtained from Fisher 344 rats and irradiated by a single exposure of 60 Gy to produce bones that were no longer viable. Osteogenic matrix cell sheets were created from rat bone marrow-derived stromal cells (BMSCs). After wrapping the dead bone with an osteogenic matrix cell sheet, it was subcutaneously transplanted into the back of a rat and harvested after 4 weeks. Bone formation around the dead bone was evaluated by X-ray imaging and histology. Alkaline phosphatase (ALP) and osteocalcin (OC) mRNA expression levels were measured to confirm osteogenesis of the transplanted bone. The contribution of donor cells to bone formation was assessed using the Sry gene and PKH26. After the cell sheet was transplanted together with dead bone, X-ray images showed abundant calcification around the dead bone. In contrast, no newly formed bone was seen in samples that were transplanted without the cell sheet. Histological sections also showed newly formed bone around dead bone in samples transplanted with the cell sheet, whereas many empty lacunae and no newly formed bone were observed in samples transplanted without the cell sheet. ALP and OC mRNA expression levels were significantly higher in dead bones transplanted with cell sheets than in those without a cell sheet (P < 0.01). Sry gene expression and cells derived from cell sheets labeled with PKH26 were detected in samples transplanted with a cell sheet, indicating survival of donor cells after transplantation. Our study indicates that osteogenic matrix cell sheet transplantation can supply osteogenesis to dead bone. Copyright © 2018. Published by Elsevier B.V.

Comparative evaluation of absorbable hemostats: advantages of fibrin-based sheets.

PubMed

Krishnan, Lissy K; Mohanty, Mira; Umashankar, P R; Lal, Arthur Vijayan

2004-11-01

Bioactive hemostats and wound dressings consist of either inherently active materials or act as delivery vehicles which contain such materials. Fibrin is a natural hemostat and scaffold, guiding the direction of wound contraction and closure. In order to improve the ease of application of liquid fibrin glue, we have made a freeze-dried form of polymerized fibrin that supports hemostasis and wound healing. The bleeding from the middle ear artery of rabbits was found to be arrested instantaneously on application of fibrin sheets, even when the animal was heparinized systemically. As the fibrin sheet was found to be fragile, gelatin was incorporated to the sheet and thus the mechanical stability was improved without compromising the hemostatic effect. The efficacy of the fabricated fibrin and fibrin-gelatin sheets to seal traumatized rat liver was compared with commercially available hemostats, Abgel (cross-linked gelatin) and Surgicel (cross-linked cellulose). Tissue compatibility of all the hemostats was studied by analyzing the liver tissue 15 days after application. While the hemostatic effect was best with fibrin and fibrin-gelatin sheets, both Surgicel and Abgel were not capable of arresting the bleeding quickly. Gross analysis of tissue on the 15th day of application, visibly, Abgel was not only degraded but resulted in severe adhesions of internal organs and histologically capsule formation around the implant was evident. Though Surgicel was also seen as cream soft material on the site of application that joined two pieces of liver, there was no adhesion of other internal organs and histologically, immune reaction and foreign-body-type giant cells were present in large amounts. Fibrin was not found grossly on application site whereas fibrin-gelatin was seen as a small white spot. Granulation tissue formation and cell migration into the fibrin-based sheets were evident, and therefore, fibrin-based sheets are not only efficient hemostats but showed optimum degradation and wound healing.

Mapping Greenland's Firn Aquifer using L-band Microwave Radiometry

NASA Astrophysics Data System (ADS)

Miller, J.; Bringer, A.; Jezek, K. C.; Johnson, J. T.; Scambos, T. A.; Long, D. G.

2016-12-01

Greenland's recently discovered firn aquifer is one of the most interesting, yet still mysterious, components of the ice sheet system. Many open questions remain regarding timescales of refreezing and/or englacial drainage of liquid meltwater, and the connections of firn aquifers to the subglacial hydrological system. If liquid meltwater production at the surface of the Greenland ice sheet continues to increase, subsequent increases in the volume of mobile liquid meltwater retained within Greenland's firn aquifer may increase the possibility of crevasse-deepening via hydrofracture. Hydrofracture is an important component of supraglacial lake drainage leading to at least temporary accelerated flow velocities and ice sheet mass balance changes. Firn aquifers may also support hydrofracture-induced drainage and thus are potentially capable of significantly influencing ice sheet mass balance and sea level rise. Spaceborne L-band microwave radiometers provide an innovative tool for ice-sheet wide mapping of the spatiotemporal variability of Greenland's firn aquifer. Both refreezing and englacial drainage may be observable given the sensitivity of the microwave response to the upper surface of liquid meltwater retained within snow and firn pore space as well as the ability of L band instruments to probe the ice sheet from the surface to the firn-ice transition at pore close-off depth. Here we combine L-band (1.4 GHz) brightness temperature observations from multiple sources to demonstrate the potential of mapping firn aquifers on ice sheets using L-band microwave radiometry. Data sources include the interferometric MIRAS instrument aboard ESA's Soil Moisture and Ocean Salinity (SMOS) satellite mission and the radiometer aboard NASA's Soil Moisture Active Passive (SMAP) satellite mission. We will also present mulit-frequency L-band brightness temperature data (0.5-2 GHz) that will be collected over several firn aquifer areas on the Greenland ice sheet by the Ohio State University developed Ultra-Wideband Software-Defined Microwave Radiometer (UWBRAD) as part of our airborne field campaign to be conducted in September 2016.

Mapping Solid and Liquid Meltwater Retention on the Greenland and Antarctic Ice Sheets from Space

NASA Astrophysics Data System (ADS)

Miller, J.; Bringer, A.; Jezek, K. C.; Johnson, J. T.; Scambos, T.; Forster, R. R.; Long, D. G.

2017-12-01

We use satellite and airborne microwave radiometry to explore the potential for mapping both solid (infiltration ice) and liquid (firn aquifers) meltwater retention on ice sheets. Meltwater retention in firn is currently poorly understood, especially on an ice sheet-scale, however, critical to understanding the ultimate fate of liquid meltwater produced at the surface of ice sheets. Is it contributing to sea level? Or, is it being buffered prior to escaping into the ocean? We previously developed a simple satellite retrieval technique to map firn aquifers on the Greenland ice sheet using distinct L-band brightness temperature signatures that decrease on timescales of months following surface freeze-up, however, similar L-band brightness temperature signatures that decrease on timescales ranging from weeks to days are also present throughout the percolation facies of both the Greenland and Antarctic ice sheets. We hypothesize this characteristic family of temporal signatures represents meltwater retention within firn, where slowly decreasing signatures are characteristic of meltwater retention within perennial firn aquifers, and rapidly decreasing signatures are characteristic of meltwater retention as superimposed ice. Decreasing signatures on timescales between likely represent a continuum of firn characteristics, such as transient firn aquifers, perched firn aquifers, ice layers, ice pipes and lenses, and iced firn. To investigate these temporal signatures, we use L-band (1.4 GHz) brightness temperature observations collected over the Greenland and Antarctic ice sheets by the interferometric MIRAS instrument aboard ESA's Soil Moisture and Ocean Salinity (SMOS) satellite, and the radiometer aboard NASA's Soil Moisture Active Passive (SMAP) satellite. We will also investigate spectral signatures using multi-frequency L-band brightness temperature data (0.5-2 GHz) to be collected over several firn aquifer areas on the Greenland ice sheet by the Ohio State University developed Ultra-Wideband Software-Defined Microwave Radiometer (UWBRAD) as part of our airborne field campaign to be conducted in September 2017.

Development of a new surgical sheet containing both silk fibroin and thermoplastic polyurethane for cardiovascular surgery.

PubMed

Shimada, Ryo; Konishi, Hayato; Ozawa, Hideki; Katsumata, Takahiro; Tanaka, Ryou; Nakazawa, Yasumoto; Nemoto, Shintaro

2018-05-01

The surgical sheets that are currently used for congenital cardiovascular surgery have several drawbacks, including material deterioration, calcification, and pseudo-intimal proliferation resulting in hemodynamic disturbance. The aim of this study was to evaluate a newly developed sheet made from a combination of silk fibroin (SF) and a synthetic polymer, thermoplastic polyurethane (TPU), for surgical use. The hybrid SF/TPU sheet was a non-woven fabric with nanofibers that was made using the electrospinning method. The mechanical properties of the SF/TPU sheet were characterized. To determine its biocompatibility, part of the wall of the canine descending aorta was replaced with a SF/TPU sheet as a patch. The patches were removed after 3 months and a histological examination was performed. The flexibility, water permeability, and suture retention strength of the SF/TPU sheet were excellent and equivalent to those of existing sheets. The SF/TPU sheet had excellent handling properties and fit well into the vascular wall without needle hole bleeding. The histological examination revealed that the intimal tissue was restored well over the intraluminal surface of the explanted SF/TPU sheet, the absence of calcium deposition, and minimal inflammatory reaction, without signs of degradation. The SF/TPU sheet had excellent mechanical properties and tissue biocompatibility. These favorable features and possible biodegradability of the SF portion warrant a long-term follow-up study.

The use of platelet-rich fibrin combined with periodontal ligament and jaw bone mesenchymal stem cell sheets for periodontal tissue engineering

PubMed Central

Wang, Zhong-Shan; Feng, Zhi-Hong; Wu, Guo-Feng; Bai, Shi-Zhu; Dong, Yan; Chen, Fa-Ming; Zhao, Yi-Min

2016-01-01

Periodontal regeneration involves the restoration of at least three unique tissues: cementum, periodontal ligament tissue (PDL) and alveolar bone tissue. Here, we first isolated human PDL stem cells (PDLSCs) and jaw bone mesenchymal stem cells (JBMSCs). These cells were then induced to form cell sheets using an ascorbic acid-rich approach, and the cell sheet properties, including morphology, thickness and gene expression profile, were compared. Platelet-rich fibrin (PRF) derived from human venous blood was then fabricated into bioabsorbable fibrin scaffolds containing various growth factors. Finally, the in vivo potential of a cell-material construct based on PDLSC sheets, PRF scaffolds and JBMSC sheets to form periodontal tissue was assessed in a nude mouse model. In this model, PDLSC sheet/PRF/JBMSC sheet composites were placed in a simulated periodontal space comprising human treated dentin matrix (TDM) and hydroxyapatite (HA)/tricalcium phosphate (TCP) frameworks. Eight weeks after implantation, the PDLSC sheets tended to develop into PDL-like tissues, while the JBMSC sheets tended to produce predominantly bone-like tissues. In addition, the PDLSC sheet/PRF/JBMSC sheet composites generated periodontal tissue-like structures containing PDL- and bone-like tissues. Further improvements in this cell transplantation design may have the potential to provide an effective approach for future periodontal tissue regeneration. PMID:27324079

Keratinocyte cytoskeletal roles in cell sheet engineering

PubMed Central

2013-01-01

Background There is an increasing need to understand cell-cell interactions for cell and tissue engineering purposes, such as optimizing cell sheet constructs, as well as for examining adhesion defect diseases. For cell-sheet engineering, one major obstacle to sheet function is that cell sheets in suspension are fragile and, over time, will contract. While the role of the cytoskeleton in maintaining the structure and adhesion of cells cultured on a rigid substrate is well-characterized, a systematic examination of the role played by different components of the cytoskeleton in regulating cell sheet contraction and cohesion in the absence of a substrate has been lacking. Results In this study, keratinocytes were cultured until confluent and cell sheets were generated using dispase to remove the influence of the substrate. The effects of disrupting actin, microtubules or intermediate filaments on cell-cell interactions were assessed by measuring cell sheet cohesion and contraction. Keratin intermediate filament disruption caused comparable effects on cell sheet cohesion and contraction, when compared to actin or microtubule disruption. Interfering with actomyosin contraction demonstrated that interfering with cell contraction can also diminish cell cohesion. Conclusions All components of the cytoskeleton are involved in maintaining cell sheet cohesion and contraction, although not to the same extent. These findings demonstrate that substrate-free cell sheet biomechanical properties are dependent on the integrity of the cytoskeleton network. PMID:23442760

Characteristics of the aluminum alloy sheets for forming and application examples

NASA Astrophysics Data System (ADS)

Uema, Naoyuki; Asano, Mineo

2013-12-01

In this paper, the characteristics and application examples of aluminum alloy sheets developed for automotive parts by Sumitomo Light Metal are described. For the automotive closure panels (ex., hood, back-door), an Al-Mg-Si alloy sheet having an excellent hemming performance was developed. The cause of the occurrence and the propagation of cracks by bending were considered to be the combined effect of the shear bands formed across several crystal grains and the micro-voids formed around the second phase particles. By reducing the shear band formation during bending by controlling the crystallographic texture, the Al-Mg-Si alloy sheets showed an excellent hemming performance. For the automotive outer panels (ex., roof, fender, trunk-lid), an Al-Mg alloy sheet, which has both a good hot blow formability and excellent surface appearance after hot blow forming was developed, and hot blow forming technology was put to practical use using this developed Al-Mg alloy sheet. For automotive heat insulators, a high ductile Al-Fe alloy sheet was developed. The heat insulator, which integrated several panels, was put into practical use using this developed Al-Fe alloy sheet. The textured sheet was often used as a heat insulator in order to reduce the thickness of the aluminum alloy sheet and obtain good press formability. The new textured sheet, which has both high rigidity and good press formability for heat insulators, was developed by FE analysis.

5. Historic American Buildings Survey Taken from drawing sheet, SHEET ...

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

5. Historic American Buildings Survey Taken from drawing sheet, SHEET #21, Showing the house as restored since Survey. (Dormer windows omitted as not authentic) - Samuel des Marest House, River Road, New Milford, Bergen County, NJ

Validation of Modelled Ice Dynamics of the Greenland Ice Sheet using Historical Forcing

NASA Astrophysics Data System (ADS)

Hoffman, M. J.; Price, S. F.; Howat, I. M.; Bonin, J. A.; Chambers, D. P.; Tezaur, I.; Kennedy, J. H.; Lenaerts, J.; Lipscomb, W. H.; Neumann, T.; Nowicki, S.; Perego, M.; Saba, J. L.; Salinger, A.; Guerber, J. R.

2015-12-01

Although ice sheet models are used for sea level rise projections, the degree to which these models have been validated by observations is fairly limited, due in part to the limited duration of the satellite observation era and the long adjustment time scales of ice sheets. Here we describe a validation framework for the Greenland Ice Sheet applied to the Community Ice Sheet Model by forcing the model annually with flux anomalies at the major outlet glaciers (Enderlin et al., 2014, observed from Landsat/ASTER/Operation IceBridge) and surface mass balance (van Angelen et al., 2013, calculated from RACMO2) for the period 1991-2012. The ice sheet model output is compared to ice surface elevation observations from ICESat and ice sheet mass change observations from GRACE. Early results show promise for assessing the performance of different model configurations. Additionally, we explore the effect of ice sheet model resolution on validation skill.

Geohydrology of the glacial-outwash aquifer in the Baldwinsville area, Seneca River, Onondaga County, New York

USGS Publications Warehouse

Pagano, Timothy S.; Terry, David B.; Ingram, Arlynn W.

1986-01-01

Seven sheets of map data comprise this geohydrologic report. Sheet 1, surficial geology, illustrates the distribution of: open water areas; artificial fill; made land; urban land; alluvial silt and sand; alluvial sand and gravel; peat, marl, muck and clay; lake silt and/or clay; delta sand and gravel; beach sand and gravel; outwash sand and gravel; ice contact sand and ground; thick till cover bedrock; and thin till over bedrock over the Baldwinsville Area. Sheet 2, geologic sections, shows the layering of the aforementioned components below the surface layer. Sheet 3 illustrates the water infiltration of soil zone. Sheet 4 depicts the aquifer thickness. Sheet 5 illustrates the potentiometric surface, and Sheet 6 the well yield. Finally, Sheet 7 shows the land use in the region, specifically: industrial and extractive; commercial and services; transportation; farmland; forestland; residential; open public land; and water and wetlands. (Lantz-PTT)

Chest wall abscesses due to continuous application of silicone gel sheets for keloid management

PubMed Central

Tang, Hon-Lok; Lau, Keith K; Sam, Ramin; Ing, Todd S

2015-01-01

A patient with three episodes of chest wall abscesses as a result of 6 years of round-the-clock, uninterrupted (except during bathing) application of silicone gel sheets to a chest wall keloid is described. Two of the episodes occurred during hot weather. It is suggested that, in the space beneath the silicone sheet, the higher humidity and temperature, both generated as a result of prolonged sheeting, especially during hot weather, might have caused the keloid and its neighbouring skin to become soggy. This sogginess might have facilitated bacterial invasion. It is suggested that some sheeting-free time during a 24 h period might be indicated so that a keloid and its adjacent skin have the time to recover from their sheeting-induced sogginess. A sheeting-free period might especially be needed in the face of sweat accumulation beneath the silicone sheet. PMID:25920733

Chest wall abscesses due to continuous application of silicone gel sheets for keloid management.

PubMed

Tang, Hon-Lok; Lau, Keith K; Sam, Ramin; Ing, Todd S

2015-04-28

A patient with three episodes of chest wall abscesses as a result of 6 years of round-the-clock, uninterrupted (except during bathing) application of silicone gel sheets to a chest wall keloid is described. Two of the episodes occurred during hot weather. It is suggested that, in the space beneath the silicone sheet, the higher humidity and temperature, both generated as a result of prolonged sheeting, especially during hot weather, might have caused the keloid and its neighbouring skin to become soggy. This sogginess might have facilitated bacterial invasion. It is suggested that some sheeting-free time during a 24 h period might be indicated so that a keloid and its adjacent skin have the time to recover from their sheeting-induced sogginess. A sheeting-free period might especially be needed in the face of sweat accumulation beneath the silicone sheet. 2015 BMJ Publishing Group Ltd.

Electromagnetic augmentation for casting of thin metal sheets

DOEpatents

Hull, J.R.

1987-10-28

Thin metal sheets are cast by magnetically levitating molten metal deposited in a model within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled by the water-cooled walls of the mold to form a solid metal sheet. A conducting shield is electrically coupled to the molten metal sheet to provide a return path for eddy currents induced in the metal sheet by the current in the AC conducting coils. In another embodiment, a DC conducting coil is coupled to the metal sheet for providing a direct current therein which interacts with the magnetic field to levitate the moving metal sheet. Levitation of the metal sheet in both molten and solid forms reduces its contact pressure with the mold walls while maintaining sufficient engagement therebetween to permit efficient conductive cooling by the mold through which a coolant fluid may be circulated. 8 figs.

Experimental formability analysis of bondal sandwich sheet

NASA Astrophysics Data System (ADS)

Kami, Abdolvahed; Banabic, Dorel

2018-05-01

Metal/polymer/metal sandwich sheets have recently attracted the interests of industries like automotive industry. These sandwich sheets have superior properties over single-layer metallic sheets including good sound and vibration damping and light weight. However, the formability of these sandwich sheets should be enhanced which requires more research. In this paper, the formability of Bondal sheet (DC06/viscoelastic polymer/DC06 sandwich sheet) was studied through different types of experiments. The mechanical properties of Bondal were determined by uniaxial tensile tests. Hemispherical punch stretching and hydraulic bulge tests were carried out to determine the forming limit diagram (FLD) of Bondal. Furthermore, cylindrical and square cup drawing tests were performed in dry and oil lubricated conditions. These tests were conducted at different blank holding forces (BHFs). An interesting observation about Bondal sheet deep drawing was obtaining of higher drawing depths at dry condition in comparison with oil-lubricated condition.

Continuous development of current sheets near and away from magnetic nulls

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, Sanjay; Bhattacharyya, R.

2016-04-15

The presented computations compare the strength of current sheets which develop near and away from the magnetic nulls. To ensure the spontaneous generation of current sheets, the computations are performed congruently with Parker's magnetostatic theorem. The simulations evince current sheets near two dimensional and three dimensional magnetic nulls as well as away from them. An important finding of this work is in the demonstration of comparative scaling of peak current density with numerical resolution, for these different types of current sheets. The results document current sheets near two dimensional magnetic nulls to have larger strength while exhibiting a stronger scalingmore » than the current sheets close to three dimensional magnetic nulls or away from any magnetic null. The comparative scaling points to a scenario where the magnetic topology near a developing current sheet is important for energetics of the subsequent reconnection.« less

Multilayer radiation shield

DOEpatents

Urbahn, John Arthur; Laskaris, Evangelos Trifon

2009-06-16

A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

Depth and areal extent of sheet and rill erosion based on radionuclides in soils and suspended sediment

NASA Astrophysics Data System (ADS)

Whiting, Peter J.; Bonniwell, E. Chris; Matisoff, Gerald

2001-12-01

Sheetwash and rilling are two important mechanisms of soil erosion by runoff. The relative contribution of each mechanism has been a vexing question because measuring thin sheet erosion is difficult. Fortuitously, various fallout radionuclides have distinct distributions in the soil column; thus, different depths of erosion produce suspended sediment with unique radionuclide signatures. Those signatures can be used to estimate the depth and areal extent of sheet and rill erosion. We developed a model to execute multiple mass balances on soil and radionuclides to quantify these erosion mechanisms. Radionuclide activities (7Be, 137Cs, 210Pb) in the soil of a 6.03 ha agricultural field near Treynor, Iowa, and in suspended sediment washed off the field during thunderstorm runoff were determined by gamma spectroscopy. Using the model, we examined 15.5 million possible combinations of the depth and areal extent of rill and sheet erosion. The best solution to the mass balances corresponded to rills eroding 0.38% of the basin to a depth of 35 mm and sheetwash eroding 37% of the basin to a depth of 0.012 mm. Rill erosion produced 29 times more sediment than sheet erosion.

Universal inverse design of surfaces with thin nematic elastomer sheets.

PubMed

Aharoni, Hillel; Xia, Yu; Zhang, Xinyue; Kamien, Randall D; Yang, Shu

2018-06-21

Programmable shape-shifting materials can take different physical forms to achieve multifunctionality in a dynamic and controllable manner. Although morphing a shape from 2D to 3D via programmed inhomogeneous local deformations has been demonstrated in various ways, the inverse problem-finding how to program a sheet in order for it to take an arbitrary desired 3D shape-is much harder yet critical to realize specific functions. Here, we address this inverse problem in thin liquid crystal elastomer (LCE) sheets, where the shape is preprogrammed by precise and local control of the molecular orientation of the liquid crystal monomers. We show how blueprints for arbitrary surface geometries can be generated using approximate numerical methods and how local extrinsic curvatures can be generated to assist in properly converting these geometries into shapes. Backed by faithfully alignable and rapidly lockable LCE chemistry, we precisely embed our designs in LCE sheets using advanced top-down microfabrication techniques. We thus successfully produce flat sheets that, upon thermal activation, take an arbitrary desired shape, such as a face. The general design principles presented here for creating an arbitrary 3D shape will allow for exploration of unmet needs in flexible electronics, metamaterials, aerospace and medical devices, and more.

Influence of Mg doping on ZnO nanoparticles decorated on graphene oxide (GO) crumpled paper like sheet and its high photo catalytic performance under sunlight

NASA Astrophysics Data System (ADS)

Labhane, P. K.; Sonawane, S. H.; Sonawane, G. H.; Patil, S. P.; Huse, V. R.

2018-03-01

Mg doped ZnO nanoparticles decorated on graphene oxide (GO) sheets were synthesized by a wet impregnation method. The effect of Mg doping on ZnO and ZnO-GO composite has been evaluated by using x-ray diffraction (XRD), Williamson-Hall Plot (Wsbnd H Plot), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and energy dispersive x-ray spectroscopy (EDX). The physical parameters of as-prepared samples were estimated by XRD data. FESEM and HR-TEM images showed the uniform distribution of nanoparticles on GO crumpled paper like sheet. Solar light photocatalytic activities of samples were evaluated spectrophotometrically by the degradation of p-nitrophenol (PNP) and indigo carmine (IC) solution. Mgsbnd ZnO decorated on GO sheets exhibit excellent catalytic efficiency compared to all other prepared samples under identical conditions, degrading PNP and IC nearly 99% within 60 min under sunlight. The effective degradation by Mgsbnd ZnO decorated on GO sheet would be due to extended solar light absorption, enhanced adsorptivity on the composite catalyst surface and efficient charge separation of photo-induced electrons. Finally, plausible mechanism was suggested with the help of scavengers study.

Advances in modelling subglacial lakes and their interaction with the Antarctic ice sheet.

PubMed

Pattyn, Frank; Carter, Sasha P; Thoma, Malte

2016-01-28

Subglacial lakes have long been considered hydraulically isolated water bodies underneath ice sheets. This view changed radically with the advent of repeat-pass satellite altimetry and the discovery of multiple lake discharges and water infill, associated with water transfer over distances of more than 200 km. The presence of subglacial lakes also influences ice dynamics, leading to glacier acceleration. Furthermore, subglacial melting under the Antarctic ice sheet is more widespread than previously thought, and subglacial melt rates may explain the availability for water storage in subglacial lakes and water transport. Modelling of subglacial water discharge in subglacial lakes essentially follows hydraulics of subglacial channels on a hard bed, where ice sheet surface slope is a major control on triggering subglacial lake discharge. Recent evidence also points to the development of channels in deformable sediment in West Antarctica, with significant water exchanges between till and ice. Most active lakes drain over short time scales and respond rapidly to upstream variations. Several Antarctic subglacial lakes exhibit complex interactions with the ice sheet due to water circulation. Subglacial lakes can therefore-from a modelling point of view-be seen as confined small oceans underneath an imbedded ice shelf. © 2015 The Author(s).

Exploring reconnection, current sheets, and dissipation in a laboratory MHD turbulence experiment

NASA Astrophysics Data System (ADS)

Schaffner, D. A.

2015-12-01

The Swarthmore Spheromak Experiment (SSX) can serve as a testbed for studying MHD turbulence in a controllable laboratory setting, and in particular, explore the phenomena of reconnection, current sheets and dissipation in MHD turbulence. Plasma with turbulently fluctuating magnetic and velocity fields can be generated using a plasma gun source and launched into a flux-conserving cylindrical tunnel. No background magnetic field is applied so internal fields are allowed to evolve dynamically. Point measurements of magnetic and velocity fluctuations yield broadband power-law spectra with a steepening breakpoint indicative of the onset of a dissipation scale. The frequency range at which this steepening occurs can be correlated to the ion inertial scale of the plasma, a length which is characteristic of the size of current sheets in MHD plasmas and suggests a connection to dissipation. Observation of non-Gaussian intermittent jumps in magnetic field magnitude and angle along with measurements of ion temperature bursts suggests the presence of current sheets embedded within the turbulent plasma, and possibly even active reconnection sites. Additionally, structure function analysis coupled with appeals to fractal scaling models support the hypothesis that current sheets are associated with dissipation in this system.

Adsorption of sugars on Al- and Ga-doped boron nitride surfaces: A computational study

NASA Astrophysics Data System (ADS)

Darwish, Ahmed A.; Fadlallah, Mohamed M.; Badawi, Ashraf; Maarouf, Ahmed A.

2016-07-01

Molecular adsorption on surfaces is a key element for many applications, including sensing and catalysis. Non-invasive sugar sensing has been an active area of research due to its importance to diabetes care. The adsorption of sugars on a template surface study is at the heart of matter. Here, we study doped hexagonal boron nitride sheets (h-BNNs) as adsorbing and sensing template for glucose and glucosamine. Using first principles calculations, we find that the adsorption of glucose and glucosamine on h-BNNs is significantly enhanced by the substitutional doping of the sheet with Al and Ga. Including long range van der Waals corrections gives adsorption energies of about 2 eV. In addition to the charge transfer occurring between glucose and the Al/Ga-doped BN sheets, the adsorption alters the size of the band gap, allowing for optical detection of adsorption. We also find that Al-doped boron nitride sheet is better than Ga-doped boron nitride sheet to enhance the adsorption energy of glucose and glucosamine. The results of our work can be potentially utilized when designing support templates for glucose and glucosamine.

Are current sheets the boundary of fluxtubes in the solar wind? -- A study from multiple spacecraft observation

NASA Astrophysics Data System (ADS)

Li, G.; Arnold, L.; Miao, B.; Yan, Y.

2011-12-01

G. Li (1,2), L. Arnold (1), B. Miao (3) and Y. Yan (4) (1) Department of Physics, University of Alabama in Huntsville Huntsville, AL, 35899 (2) CSPAR, University of Alabama in Huntsville Huntsville, AL, 35899 (3) School of Earth and Space Sciences, University of Science and Technology of CHINA, Hefei, China (4) Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Science, Beijing 100012, China Current sheets is a common structure in the solar wind and is a significant source of solar wind MHD turbulence intermittency. The origin of these structure is presently unknown. Non-linear interactions of the solar wind MHD turbulence can spontaneously generate these structures. On the other hand, there are proposals that these structures may represent relic structures having solar origins. Using a technique developed in [1], we examine current sheets in the solar wind from multiple spacecraft. We identify the "single-peak" and "double-peak" events in the solar wind and discuss possible scenarios for these events and its implication of the origin of the current sheets. [1] Li, G., "Identify current-sheet-like structures in the solar wind", ApJL 672, L65, 2008.

Polycrystalline silicon sheets for solar cells by the spinning method

NASA Astrophysics Data System (ADS)

Maeda, Y.; Yokoyama, T.; Hide, I.

1984-03-01

A new method has been developed in which polycrystalline silicon sheets are formed directly from molten silicon on a spinning wheel. The sheet is 5 cm x 5 cm, 0.1-0.5 mm thick, and made at a rate of four sheets per 15 s; power conversion rate of a solar cell assembled with these silicon sheets is more than 10 percent.

Photocatalytic activity and antimicrobial properties of paper sheets modified with TiO2/Sodium alginate nanocomposites.

PubMed

Abdel Rehim, Mona H; El-Samahy, Magda A; Badawy, Abdelrahman A; Mohram, Maysa E

2016-09-05

Photocatalytic paper sheets were prepared by addition of different ratios of TiO2/Sodium alginate (TSA) nanocomposite. The modified paper sheets were characterized by XRD, TGA. Their morphology was studied by scanning electron microscope (SEM) and energy dispersive X-ray (EDX). Photocatalytic activity of modified paper has been studied by analysis of chemical oxygen demand (COD) of waste-water. The results confirmed the mineralization of the waste-water and enhanced removal of chemical oxygen demand (COD) by increasing the amount of photocatalyst in the paper. Moreover, the results also confirmed that presence of sodium alginate as biopolymer increased adhesion of nanoparticles to paper fibers and reduced the harmful effect of the photocatalyst on them. The paper sheets containing 7% as well as 15% TSA showed high photocatalytic activity and anti-bacterial effect against Salmonella typhimurium higher than standard antibiotic beside other microorganisms such as Candida albicans. The maximum antimicrobial effect was found in case of specimen loaded with 15% TSA. Moreover, it was found that by adding 20% TSA to the paper matrix, the properties of the paper composite collapse. The obtained results confirm the possible utilization of the modified paper in both hygienic and food packaging applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sporicidal efficacy of thermal-sprayed copper alloy coating.

PubMed

Shafaghi, Romina; Mostaghimi, Javad; Pershin, Valerian; Ringuette, Maurice

2017-05-01

Approximately 200 000 Canadians acquire healthcare-associated bacterial infections each year and several-fold more acquire food-borne bacterial illnesses. Bacterial spores are particularly problematic because they can survive on surfaces for several months. Owing to its sporicidal activity, copper alloy sheet metal is sometimes used in hospital settings, but its widespread use is limited by cost and incompatibility with complex furniture and instrument designs and topographies. A potential alternative is the use of thermal spray technology to coat surfaces with copper alloys. We compared the sporicidal activity of thermally sprayed copper alloy on stainless steel with that of copper alloy sheet metal against Bacillus subtilis spores. Spores remained intact for at least 1 week on uncoated stainless steel, whereas spore fragmentation was initiated within 2 h of exposure to either copper surface. Less than 15% of spores were viable 2 h after exposure to either copper surface, as compared with stainless steel. By day 7, only degraded spores and petal-like nanoflowers were present on the copper surfaces. Nanoflowers, which are laminar arrangements of thin crystal sheets composed of carbon - copper phosphate, appeared to be derived from the degraded spores. Altogether, these results indicate that a thermal-sprayed copper alloy coating on stainless steel provides sporicidal activity similar to that afforded by copper alloy sheet metal.

Synthesis of N-doped microporous carbon via chemical activation of polyindole-modified graphene oxide sheets for selective carbon dioxide adsorption.

PubMed

Saleh, Muhammad; Chandra, Vimlesh; Kemp, K Christian; Kim, Kwang S

2013-06-28

A polyindole-reduced graphene oxide (PIG) hybrid was synthesized by reducing graphene oxide sheets in the presence of polyindole. We have shown PIG as a material for capturing carbon dioxide (CO2). The PIG hybrid was chemically activated at temperatures of 400-800 °C, which resulted in nitrogen (N)-doped graphene sheets. The N-doped graphene sheets are microporous with an adsorption pore size of 0.6 nm for CO2 and show a maximum (Brunauer, Emmet and Teller) surface area of 936 m(2) g(-1). The hybrid activated at 600 °C (PIG6) possesses a surface area of 534 m(2) g(-1) and a micropore volume of 0.29 cm(3) g(-1). PIG6 shows a maximum CO2 adsorption capacity of 3.0 mmol g(-1) at 25 °C and 1 atm. This high CO2 uptake is due to the highly microporous character of the material and its N content. The material retains its original adsorption capacity on recycling even after 10 cycles (within experimental error). PIG6 also shows high adsorption selectivity ratios for CO2 over N2, CH4 and H2 of 23, 4 and 85 at 25 °C, respectively.

Topical Application of a Silicone Gel Sheet with Verapamil Microparticles in a Rabbit Model of Hypertrophic Scar.

PubMed

Rha, Eun Young; Kim, Yun Ho; Kim, Tae-Jung; Yoo, Gyeol; Rhie, Jong Won; Kim, Hyun-Jung; Park, Il-Kyu

2016-01-01

The authors developed a novel treatment based on the topical application of a silicone gel sheet containing verapamil microparticles. The ability of these silicone gel sheets to inhibit hypertrophic scar in a rabbit ear wound model was examined. Ten New Zealand White rabbits with a total of 80 wounds in both ears were used in this study. The rabbits were divided into five groups (control; silicone gel sheet; and silicone gel sheet plus 0.25, 2.5, and 25 mg of verapamil per gram). Histopathologic findings were quantified. The mean scar elevation index, fibroblast counts, and capillary counts differed significantly among the five groups (p < 0.05). The median scar elevation index was significantly lower in the silicone gel sheet plus 2.5 mg of verapamil per gram group than in the silicone gel sheet group (1.2 versus 2.2). The median number of fibroblasts was significantly lower in the silicone gel sheet plus 0.25 mg of verapamil per gram group than in the silicone gel sheet group (172.5 versus 243). In the median number of capillary lumina, there was no significant difference between the silicone gel sheet group and the silicone gel sheet plus 0.25, 2.5, and 25 mg of verapamil per gram groups (28.5, 18, 20, and 18, respectively). Topical application of a silicone gel sheet with verapamil microparticles may be a novel, effective treatment method for hypertrophic scar, but its safety and efficacy in humans must be tested in clinical trials.

Continuous, Pulsed Export of Methane-Supersaturated Meltwaters from the Bed of the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Lamarche-Gagnon, G.; Wadham, J.; Beaton, A.; Fietzek, P.; Stanley, K. M.; Tedstone, A.; Sherwood Lollar, B.; Lacrampe Couloume, G.; Telling, J.; Liz, B.; Hawkings, J.; Kohler, T. J.; Zarsky, J. D.; Stibal, M.; Mowlem, M. C.

2016-12-01

Both past and present ice sheets have been proposed to cap large quantities of methane (CH4), on orders of magnitude significant enough to impact global greenhouse gas concentrations during periods of rapid ice retreat. However, to date most evidence for sub-ice sheet methane has been indirect, derived from calculations of the methanogenic potential of basal-ice microbial communities and biogeochemical models; field-based empirical measurements are lacking from large ice sheet catchments. Here, we present the first continuous, in situ record of dissolved methane export from a large catchment of the Greenland Ice Sheet (GrIS) in South West Greenland from May-July 2015. Our results indicate that glacial runoff was continuously supersaturated with methane over the observation period (dissolved CH4 concentrations of 30-700 nM), with total methane flux rising as subglacial discharge increased. Periodic subglacial drainage events, characterised by rapid changes (i.e. pulses) in meltwater hydrochemistry, also coincided with a rise in methane concentrations. We argue that these are likely indicative of the flushing of subglacial reservoirs of CH4 beneath the ice sheet. Total methane export was relatively modest when compared to global methane budgets, but too high to be explained by previously determined methanogenic rates from Greenland basal ice. Discrepancies between estimated Greenland methane reserves and observed fluxes stress the need to further investigate GrIS methane fluxes and sources, and suggest a more biogeochemically active subglacial environment than previously considered. Results indicate that future warming, and a coincident increase in ice melt rates, would likely make the GrIS, and by extension the Antarctic Ice Sheet, more significant sources of atmospheric methane, consequently acting as a positive feedback to a warming climate.

Micro-Scale Mechanical Testing of Non-Woven Carbon Nanotube Sheets and Yarns

NASA Technical Reports Server (NTRS)

Magargee, J.; Morestin, F.; Cao, J.; Jones, J. S.

2013-01-01

Non-woven carbon nanotube (CNT) sheets and yarns were tested using a novel micro-scale mechanical testing system. CNT sheets were observed to delaminate during uniaxial testing using an adbesive gripping method, resulting from a higher proportion of load bearing in the outer sheets versus internal sheets and an apparently low interlaminar shear strength. In response to this, a new spool-grip method was used to alleviate non-uniform through-thickness stresses, circumvent premature delamination, and allow the sheet material to sustain a 72% increase in measured tensile strength. Furthermore, tension tests of CNT yarns showed that the yarn-structure was approximaiely 7 times stronger than the sheet structure, owing to a higher degree of CNT alignment in the test direction.

Spiral wound extraction cartridge

DOEpatents

Wisted, Eric E.; Lundquist, Susan H.

1999-01-01

A cartridge device for removing an analyte from a fluid comprises a hollow core, a sheet composite comprising a particulate-loaded porous membrane and optionally at least one reinforcing spacer sheet, the particulate being capable of binding the analyte, the sheet composite being formed into a spiral configuration about the core, wherein the sheet composite is wound around itself and wherein the windings of sheet composite are of sufficient tightness so that adjacent layers are essentially free of spaces therebetween, two end caps which are disposed over the core and the lateral ends of the spirally wound sheet composite, and means for securing the end caps to the core, the end caps also being secured to the lateral ends of the spirally wound sheet composite. A method for removing an analyte from a fluid comprises the steps of providing a spirally wound element of the invention and passing the fluid containing the analyte through the element essentially normal to a surface of the sheet composite so as to bind the analyte to the particulate of the particulate-loaded porous membrane, the method optionally including the step of eluting the bound analyte from the sheet composite.

Durability improvements of two-dimensional metal nanoparticle sheets by molecular cross-linked structures between nanoparticles

NASA Astrophysics Data System (ADS)

Saito, Noboru; Ryuzaki, Sou; Wang, Pangpang; Park, Susie; Sakai, Nobuyuki; Tatsuma, Tetsu; Okamoto, Koichi; Tamada, Kaoru

2018-03-01

The durability of two-dimensional metal nanoparticle sheets is a crucial factor for realizing next-generation optoelectronic devices based on plasmonics such as organic light-emitting diodes. Here, we report improvements in the durability of Ag nanoparticle sheets by forming alkanedithiol (DT16) cross-linked structures between the nanoparticles. The cross-linked structures in a sheet were fabricated by the self-assembly of DT16-capped Ag nanoparticles with 10% coverage (AgDT16). The durabilities for thermal, organic solvent, and oxidation reactions of AgDT16 sheets were found to be improved owing to the cross-linked structures by comparing Ag nanoparticle sheets without the cross-linked structures. The absorbance spectra revealed that the Ag nanoparticle sheets without the structure are markedly damaged by each durability test, whereas the AgDT16 sheets remain. The molecular cross-linked structures between nanoparticles in two-dimansional metal nanoparticle sheets were found to have the potential to play a key role in the realization of plasmonic optoelectronic devices including metal nanoparticles.

Custom-shaping system for bone regeneration by seeding marrow stromal cells onto a web-like biodegradable hybrid sheet.

PubMed

Tsuchiya, Kohei; Mori, Taisuke; Chen, Guoping; Ushida, Takashi; Tateishi, Tetsuya; Matsuno, Takeo; Sakamoto, Michiie; Umezawa, Akihiro

2004-05-01

New bone for the repair or the restoration of the function of traumatized, damaged, or lost bone is a major clinical need, and bone tissue engineering has been heralded as an alternative strategy for regenerating bone. A novel web-like structured biodegradable hybrid sheet has been developed for bone tissue engineering by preparing knitted poly(DL-lactic-co-glycolic acid) sheets (PLGA sheets) with collagen microsponges in their openings. The PLGA skeleton facilitates the formation of the hybrid sheets into desired shapes, and the collagen microsponges in the pores of the PLGA sheet promote cell adhesion and uniform cell distribution throughout the sheet. A large number of osteoblasts established from marrow stroma adhere to the scaffolds and generate the desired-shaped bone in combination with these novel sheets. These results indicate that the web-like structured novel sheet shows promise for use as a tool for custom-shaped bone regeneration in basic research on osteogenesis and for the development of therapeutic applications. Copyright 2004 Springer-Verlag

Current state and future perspectives on coupled ice-sheet - sea-level modelling

NASA Astrophysics Data System (ADS)

de Boer, Bas; Stocchi, Paolo; Whitehouse, Pippa L.; van de Wal, Roderik S. W.

2017-08-01

The interaction between ice-sheet growth and retreat and sea-level change has been an established field of research for many years. However, recent advances in numerical modelling have shed new light on the precise interaction of marine ice sheets with the change in near-field sea level, and the related stability of the grounding line position. Studies using fully coupled ice-sheet - sea-level models have shown that accounting for gravitationally self-consistent sea-level change will act to slow down the retreat and advance of marine ice-sheet grounding lines. Moreover, by simultaneously solving the 'sea-level equation' and modelling ice-sheet flow, coupled models provide a global field of relative sea-level change that is consistent with dynamic changes in ice-sheet extent. In this paper we present an overview of recent advances, possible caveats, methodologies and challenges involved in coupled ice-sheet - sea-level modelling. We conclude by presenting a first-order comparison between a suite of relative sea-level data and output from a coupled ice-sheet - sea-level model.

The dynamics and shapes of a viscous sheet spreading on a moving liquid bath

NASA Astrophysics Data System (ADS)

Sebilleau, J.; Lebon, L.; Limat, L.; Quartier, L.; Receveur, M.

2010-10-01

We investigate the shape and dynamics of a floating viscous sheet formed by a jet falling on a static or moving bath under partial wetting conditions. For a static bath, the viscous sheet has a circular shape and spreads with a uniform thickness that is surprisingly larger than the static Langmuir equilibrium thickness. This thickening effect seems to be linked to a peculiarity of the oil used for the bath, which is in situation of total wetting on the sheet surface, and climbs the sheet a bit like a macroscopic "precursor film" that increases dissipation at the sheet perimeter. For a moving bath, the viscous sheet evolves from an ellipse to a ribbon, a transient remarkable pear shape being observed between these two states. A simple kinematic model of advection of the spreading sheet by the bath predicts very well the characteristics of the ribbon regime. Convected sheets whose shape is reminiscent of pendant drops in 2D are also observed at higher bath velocity, with interesting pinch off phenomena.

The Impact of Geothermal Heat on the Scandinavian Ice Sheet's LGM Extent

NASA Astrophysics Data System (ADS)

Szuman, Izabela; Ewertowski, Marek W.; Kalita, Jakub Z.

2016-04-01

The last Scandinavian ice sheet attained its most southern extent over Poland and Germany, protruding c. 200 km south of the main ice sheet mass. There are number of factors that may control ice sheet dynamics and extent. One of the less recognised is geothermal heat, which is heat that is supplied to the base of the ice sheet. A heat at the ice/bed interface plays a crucial role in controlling ice sheet stability, as well as impacting basal temperatures, melting, and ice flow velocities. However, the influence of geothermal heat is still virtually neglected in reconstructions and modelling of paleo-ice sheets behaviour. Only in a few papers is geothermal heat recalled though often in the context of past climatic conditions. Thus, the major question is if and how spatial differences in geothermal heat had influenced paleo-ice sheet dynamics and in consequence their extent. Here, we assumed that the configuration of the ice sheet along its southern margin was moderately to strongly correlated with geothermal heat for Poland and non or negatively correlated for Germany.

On the balance of stresses in the plasma sheet.

NASA Technical Reports Server (NTRS)

Rich, F. J.; Wolf, R. A.; Vasyliunas, V. M.

1972-01-01

The stress resulting from magnetic tension on the neutral sheet must, in a steady state, be balanced by any one or a combination of (1) a pressure gradient in the direction along the axis of the tail, (2) a similar gradient of plasma flow kinetic energy, and (3) the tension resulting from a pressure anisotropy within the plasma sheet. Stress balance in the first two cases requires that the ratios h/LX and BZ/BX be of the same order of magnitude, where h is the half-thickness of the neutral sheet, LX is the length scale for variations along the axis of the tail, and BZ and BX are the magnetic field components in the plasma sheet just outside the neutral sheet. The second case requires, in addition, that the plasma flow speed within the neutral sheet be of the order of or larger than the Alfven speed outside the neutral sheet. Stress balance in the third case requires that just outside the neutral sheet the plasma pressure obey the marginal firehose stability condition.

Theoretical and experimental emittance measurements for a thin liquid sheet flow

NASA Technical Reports Server (NTRS)

Englehart, Amy N.; Mcconley, Marc W.; Chubb, Donald L.

1995-01-01

Surface tension forces at the edges of a thin liquid (approximately 200 microns) sheet flow result in a triangularly shaped sheet. Such a geometry is ideal for an external flow radiator. Since the fluid must have very low vapor pressure, Dow Corning 705 silicone oil was used and the emittance of a flowing sheet of oil was determined by two methods. The emittance was derived as a function of the temperature drop between the top of the sheet and the coalescence point of the sheet, the sink temperature, the volumetric flow and the length of the sheet. the emittance for the oil was also calculated using an extinction coefficient determined from spectral transmittance data of the oil. The oil's emittance ranges from .67 to .87 depending on the sheet thickness and sheet temperature. The emittance derived from the temperature drop was slightly less than the emittance calculated from transmittance data. An investigation of temperature fluctuation upstream of the slit plate was also done. The fluctuations were determined to be negligible, not affecting the temperature drop which was due to radiation.

Coos County Youth and Out-of-School Activities: Patterns of Involvement and Barriers to Participation. New England Fact Sheet No. 7, Fall 2012

ERIC Educational Resources Information Center

Sharp, Erin Hiley

2012-01-01

This fact sheet draws from surveys administered to a cohort of 416 participants in 7th grade in 2008, again when they were in 8th grade in 2009, and most recently as 10th graders in 2011 to look at patterns of participation in structured activities over time and whether male and female students differ in these patterns of participation. It also…

Electron gun controlled smart structure

DOEpatents

Martin, Jeffrey W.; Main, John Alan; Redmond, James M.; Henson, Tammy D.; Watson, Robert D.

2001-01-01

Disclosed is a method and system for actively controlling the shape of a sheet of electroactive material; the system comprising: one or more electrodes attached to the frontside of the electroactive sheet; a charged particle generator, disposed so as to direct a beam of charged particles (e.g. electrons) onto the electrode; a conductive substrate attached to the backside of the sheet; and a power supply electrically connected to the conductive substrate; whereby the sheet changes its shape in response to an electric field created across the sheet by an accumulation of electric charge within the electrode(s), relative to a potential applied to the conductive substrate. Use of multiple electrodes distributed across on the frontside ensures a uniform distribution of the charge with a single point of e-beam incidence, thereby greatly simplifying the beam scanning algorithm and raster control electronics, and reducing the problems associated with "blooming". By placing a distribution of electrodes over the front surface of a piezoelectric film (or other electroactive material), this arrangement enables improved control over the distribution of surface electric charges (e.g. electrons) by creating uniform (and possibly different) charge distributions within each individual electrode. Removal or deposition of net electric charge can be affected by controlling the secondary electron yield through manipulation of the backside electric potential with the power supply. The system can be used for actively controlling the shape of space-based deployable optics, such as adaptive mirrors and inflatable antennae.

Organic carbon export from the Greenland Ice Sheet: sources, sinks and downstream fluxes

NASA Astrophysics Data System (ADS)

Wadham, J. L.; Lawson, E.; Tranter, M.; Stibal, M.; Telling, J.; Lis, G. P.; Nienow, P. W.; Anesio, A. M.; Butler, C. E.

2012-12-01

Runoff from small glacier systems has been shown to contain dissolved organic carbon (DOC) rich in low molecular weight (LMW), and hence more labile forms, designating glaciers as an important source of carbon for downstream heterotrophic activity. Here we assess glacier surfaces as potential sources of labile DOC to downstream ecosystems, presenting data from a wide range of glacier systems to determine sources and sinks of DOC in glacial and proglacial systems. We subsequently focus upon the Greenland Ice Sheet (GrIS) which is the largest source of glacial runoff at present (400 km3 yr-1), with predicted increases in future decades. We report high fluxes of particulate organic carbon (POC), DOC and LMW labile fractions from a large GrIS catchment during two contrasting melt seasons. POC dominates OC export, is sourced from the ice sheet bed and contains a significant bioreactive component (~10% carbohydrates). The LMW-DOC "labile" fraction derives almost entirely from microbial activity on the ice sheet surface, which is supported by data from glacier systems also presented here. Annual fluxes of DOC, POC and labile components were lower in 2010 than 2009, despite a ~2 fold increase in runoff fluxes in 2010, suggesting production-limited DOC/POC sources. Scaled to the entire ice sheet, combined DOC and POC fluxes are of a similar order of magnitude to other large Arctic river systems and may represent an important source of organic carbon to the North Atlantic, Greenland and Labrador Seas.

Understanding the adsorptive interactions of arsenate-iron nanoparticles with curved fullerene-like sheets in activated carbon using a quantum mechanics/molecular mechanics computational approach.

PubMed

Ha, Nguyen Ngoc; Cam, Le Minh; Ha, Nguyen Thi Thu; Goh, Bee-Min; Saunders, Martin; Jiang, Zhong-Tao; Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z; El-Harbawi, Mohanad; Yin, Chun-Yang

2017-06-07

The prevalence of global arsenic groundwater contamination has driven widespread research on developing effective treatment systems including adsorption using various sorbents. The uptake of arsenic-based contaminants onto established sorbents such as activated carbon (AC) can be effectively enhanced via immobilization/impregnation of iron-based elements on the porous AC surface. Recent suggestions that AC pores structurally consist of an eclectic mix of curved fullerene-like sheets may affect the arsenic adsorption dynamics within the AC pores and is further complicated by the presence of nano-sized iron-based elements. We have therefore, attempted to shed light on the adsorptive interactions of arsenate-iron nanoparticles with curved fullerene-like sheets by using hybridized quantum mechanics/molecular mechanics (QMMM) calculations and microscopy characterization. It is found that, subsequent to optimization, chemisorption between HAsO 4 2- and the AC carbon sheet (endothermic process) is virtually non-existent - this observation is supported by experimental results. Conversely, the incorporation of iron nanoparticles (FeNPs) into the AC carbon sheet greatly facilitates chemisorption of HAsO 4 2- . Our calculation implies that iron carbide is formed at the junction between the iron and the AC interface and this tightly chemosorbed layer prevents detachment of the FeNPs on the AC surface. Other aspects including electronic structure/properties, carbon arrangement defects and rate of adsorptive interaction, which are determined using the Climbing-Image NEB method, are also discussed.

Ohm's law for a current sheet

NASA Technical Reports Server (NTRS)

Lyons, L. R.; Speiser, T. W.

1985-01-01

The paper derives an Ohm's law for single-particle motion in a current sheet, where the magnetic field reverses in direction across the sheet. The result is considerably different from the resistive Ohm's law often used in MHD studies of the geomagnetic tail. Single-particle analysis is extended to obtain a self-consistency relation for a current sheet which agrees with previous results. The results are applicable to the concept of reconnection in that the electric field parallel to the current is obtained for a one-dimensional current sheet with constant normal magnetic field. Dissipated energy goes directly into accelerating particles within the current sheet.

Magneto-hydrodynamics of coupled fluid-sheet interface with mass suction and blowing

NASA Astrophysics Data System (ADS)

Ahmad, R.

2016-01-01

There are large number of studies which prescribe the kinematics of the sheet and ignore the sheet's mechanics. However, the current boundary layer analysis investigates the mechanics of both the electrically conducting fluid and a permeable sheet, which makes it distinct from the other studies in the literature. One of the objectives of the current study is to (i) examine the behaviour of magnetic field effect for both the surface and the electrically conducting fluid (ii) investigate the heat and mass transfer between a permeable sheet and the surrounding electrically conducting fluid across the hydro, thermal and mass boundary layers. Self-similar solutions are obtained by considering the RK45 technique. Analytical solution is also found for the stretching sheet case. The skin friction dual solutions are presented for various types of sheet. The influence of pertinent parameters on the dimensionless velocity, shear stress, temperature, mass concentration, heat and mass transfer rates on the fluid-sheet interface is presented graphically as well as numerically. The obtained results are of potential benefit for studying the electrically conducting flow over various soft surfaces such as synthetic plastics, soft silicone sheet and soft synthetic rubber sheet. These surfaces are easily deformed by thermal fluctuations or thermal stresses.

Structure, burial history, and petroleum potential of frontal thrust belt and adjacent foreland, southwest Montana.

USGS Publications Warehouse

Perry, W.J.; Wardlaw, B.R.; Bostick, N.H.; Maughan, E.K.

1983-01-01

The frontal thrust belt in the Lima area of SW Montana consists of blind (nonsurfacing) thrusts of the Lima thrust system beneath the Lima anticline and the Tendoy thrust sheet to the W. The Tendoy sheet involves Mississippian through Cretaceous rocks of the SW-plunging nose of the Mesozoic Blacktail-Snowcrest uplift that are thrust higher (NE) onto the uplift. The front of the Tendoy sheet W of Lima locally has been warped by later compressive deformation which also involved synorogenic conglomerates of the structurally underlying Beaverhead Formation. To the N, recent extension faulting locally has dropped the front of the Tendoy sheet beneath Quaternary gravels. Rocks of the exposed Tendoy sheet have never been deeply buried, based on vitrinite relectance of = or <0.6%, conodont CAI (color alteration index) values that are uniformly 1, and on supporting organic geochemical data from Paleozoic rocks from the Tendoy thrust sheet. Directly above and W of the Tendoy sheet lie formerly more deeply buried rocks of the Medicine Lodge thrust system. Their greater burial depth is indicated by higher conodont CAI values. W-dipping post-Paleocene extension faults truncate much of the rear part of the Tendoy sheet and also separate the Medicine Lodge sheet from thrust sheets of the Beaverhead Range still farther W. -from Authors

Commercial scale production of Fe-6.5 wt. % Si sheet and its magnetic properties

NASA Astrophysics Data System (ADS)

Takada, Y.; Abe, M.; Masuda, S.; Inagaki, J.

1988-11-01

Commercial scale production of a Fe-6.5 wt. % Si sheet has been successfully developed. Presently manufactured sheets are in coil form, whose thickness ranges from 0.1 to 0.5 mm with a maximum width of 400 mm. Magnetic properties of the manufactured sheet have been investigated. The permeability of Fe-6.5 wt. % Si sheet is about 10 times higher than the conventional nonoriented silicon steel sheet. The core losses are less than half the conventional, and even less than that of the grain-oriented silicon steel sheet at frequencies over 400 Hz. Superior soft magnetic properties are attributed to the low magnetostriction and high electric resistivity of this alloy. It is well known that the Fe-6.5 wt. % Si alloy has poor ductility in conventional mechanical work. But investigation of the forming conditions has enabled the stamping and bending of alloy sheets. Low core losses and high permeability make Fe-6.5 wt. % Si sheet adequate for motor cores, transformer cores operating at high frequencies, and magnetic shielding. Application to the micromotor core shows that Fe-6.5 wt. % Si sheet reduces the consumption of no-load electric current by 25% in comparison with the conventional silicon steel.

9. Photocopy of architectural drawing (from blueprint at Fort Myer ...

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

9. Photocopy of architectural drawing (from blueprint at Fort Myer Engineer Activity) 'Double Set of Non-Commissioned Officers Qrs.' Quartermaster Generals Office, sheet 1 and unnumbered sheet, standard plan 23, June 1891. lithograph on linen architectural drawing 2. PLANS, 1 SECTION, 2 DETAILS - Fort Myer, Non-Commissioned Officers Quarters, Washington Avenue between Johnson Lane & Custer Road, Arlington, Arlington County, VA

Exploring the Moon: A Teacher's Guide with Activities for Earth and Space Sciences.

ERIC Educational Resources Information Center

National Aeronautics and Space Administration, Washington, DC.

These materials have been designed for use with the upper elementary through high school levels especially, but not exclusively, with the Lunar Sample Disk. This book contains: information on the Lunar Sample Disk, a curriculum content matrix, a teacher's guide, Moon ABCs fact sheet, rock ABCs fact sheet, Progress in Lunar Science chart, 17…

"Ramona Quimby": Adapted by Len Jenkin from the Ramona Books by Beverly Cleary. Cue Sheet for Students.

ERIC Educational Resources Information Center

Aguirre-Sacasa, Roberto

This performance guide is designed for teachers to use with students before and after a performance of "Ramona Quimby," adapted by Len Jenkin from the Ramona books by Beverly Cleary. The guide, called a "Cuesheet," contains seven activity sheets for use in class, addressing: (1) The Characters (introducing the characters in the…

"Caddie Woodlawn": Adapted by Greg Gunning from the Novel by Carol Ryrie Brink. Cue Sheet for Students.

ERIC Educational Resources Information Center

Aguirre-Sacasa, Roberto

This performance guide is designed for teachers to use with students before and after a performance of "Caddie Woodlawn," adapted by Greg Gunning from the novel by Carol Ryrie Brink. The guide, called a "Cuesheet," contains seven activity sheets for use in class, addressing: (1) The Characters (introducing the characters in the…

"Sundiata, Lion King of Mali." Adapted by Kim Hines, Featuring Griot Alhaji Papa Susso, Cue Sheet for Students.

ERIC Educational Resources Information Center

Freeman, Aakhu TuahNera

This performance guide is designed for teachers to use with students before and after a performance of "Sundiata: Lion King of Mali," adapted by Kim Hines and featuring Griot Alhaji Papa Susso. The guide, called a "Cuesheet," contains seven activity sheets for use in class, addressing: (1) Sundiata: Man & Myth (discusses…

Fuels planning: science synthesis and integration; social issues fact sheet 02: Developing personal responsibility for fuels reduction: Types of information to encourage proactive behavior

Treesearch

Rocky Mountain Research Station USDA Forest Service

2004-01-01

Fuels management responsibilities may include providing local property owners with the information for taking responsibility for reducing fuels on their land. This fact sheet discusses three different types of information that may be useful in programs to engage property owners in fuel reduction activities.

Fuels planning: science synthesis and integration; economic uses fact sheet 02: log hauling cost

Treesearch

Rocky Mountain Research Station USDA Forest Service

2004-01-01

Knowing the cost of fuel reduction treatments and associated activities, such as hauling cut trees, is essential for fire and fuels planning. This fact sheet explores the main factors that determine the cost of hauling cut trees and points the user to an interactive tool that can help plan for those and other expenses.

Enabling Colloidal Synthesis of Edge-Oriented MoS2 with Expanded Interlayer Spacing for Enhanced HER Catalysis.

PubMed

Sun, Yugang; Alimohammadi, Farbod; Zhang, Dongtang; Guo, Guangsheng

2017-03-08

By selectively promoting heterogeneous nucleation/growth of MoS 2 on graphene monolayer sheets, edge-oriented (EO) MoS 2 nanosheets with expanded interlayer spacing (∼9.4 Å) supported on reduced graphene oxide (rGO) sheets were successfully synthesized through colloidal chemistry, showing the promise in low-cost and large-scale production. The number and edge length of MoS 2 nanosheets per area of graphene sheets were tuned by controlling the reaction time in the microwave-assisted solvothermal reduction of ammonium tetrathiomolybdate [(NH 4 ) 2 MoS 4 ] in dimethylformamide. The edge-oriented and interlayer-expanded (EO&IE) MoS 2 /rGO exhibited significantly improved catalytic activity toward hydrogen evolution reaction (HER) in terms of larger current density, lower Tafel slope, and lower charge transfer resistance compared to the corresponding interlayer-expanded MoS 2 sheets without edge-oriented geometry, highlighting the importance of synergistic effect between edge-oriented geometry and interlayer expansion on determining HER activity of MoS 2 nanosheets. Quantitative analysis clearly shows the linear dependence of current density on the edge length of MoS 2 nanosheets.

THE DYNAMICAL GENERATION OF CURRENT SHEETS IN ASTROPHYSICAL PLASMA TURBULENCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howes, Gregory G.

2016-08-20

Turbulence profoundly affects particle transport and plasma heating in many astrophysical plasma environments, from galaxy clusters to the solar corona and solar wind to Earth's magnetosphere. Both fluid and kinetic simulations of plasma turbulence ubiquitously generate coherent structures, in the form of current sheets, at small scales, and the locations of these current sheets appear to be associated with enhanced rates of dissipation of the turbulent energy. Therefore, illuminating the origin and nature of these current sheets is critical to identifying the dominant physical mechanisms of dissipation, a primary aim at the forefront of plasma turbulence research. Here, we presentmore » evidence from nonlinear gyrokinetic simulations that strong nonlinear interactions between counterpropagating Alfvén waves, or strong Alfvén wave collisions, are a natural mechanism for the generation of current sheets in plasma turbulence. Furthermore, we conceptually explain this current sheet development in terms of the nonlinear dynamics of Alfvén wave collisions, showing that these current sheets arise through constructive interference among the initial Alfvén waves and nonlinearly generated modes. The properties of current sheets generated by strong Alfvén wave collisions are compared to published observations of current sheets in the Earth's magnetosheath and the solar wind, and the nature of these current sheets leads to the expectation that Landau damping of the constituent Alfvén waves plays a dominant role in the damping of turbulently generated current sheets.« less

Preliminary Investigation of Impact on Multiple-Sheet Structures and an Evaluation of the Meteoroid Hazard to Space Vehicles

NASA Technical Reports Server (NTRS)

Nysmith, C. Robert; Summers, James L.

1961-01-01

Small pyrex glass spheres, representative of stoney meteoroids, were fired into 2024-T3 aluminum alclad multiple-sheet structures at velocities to 11,000 feet per second to evaluate the effectiveness of multisheet hull construction as a means of increasing the resistance of a spacecraft to meteoroid penetrations. The results of these tests indicate that increasing the number of sheets in a structure while keeping the total sheet thickness constant and increasing the spacing between sheets both tend to increase the penetration resistance of a structure of constant weight per unit area. In addition, filling the space between the sheets with a light filler material was found to substantially increase structure penetration resistance with a small increase in weight. An evaluation of the meteoroid hazard to space vehicles is presented in the form of an illustrative-example for two specific lunar mission vehicles, a single-sheet, monocoque hull vehicle and a glass-wool filled, double-sheet hull vehicle. The evaluation is presented in terms of the "best" and the "worst" conditions that might be expected as determined from astronomical and satellite measurements, high-speed impact data, and hypothesized meteoroid structures and compositions. It was observed that the vehicle flight time without penetration can be increased significantly by use of multiple-sheet rather than single-sheet hull construction with no increase in hull weight. Nevertheless, it is evident that a meteoroid hazard exists, even for the vehicle with the selected multiple-sheet hull.

History of the Greenland Ice Sheet: paleoclimatic insights

USGS Publications Warehouse

Alley, Richard B.; Andrews, John T.; Brigham-Grette, J.; Clarke, G.K.C.; Cuffey, Kurt M.; Fitzpatrick, J.J.; Funder, S.; Marshall, S.J.; Miller, G.H.; Mitrovica, J.X.; Muhs, D.R.; Otto-Bliesner, B. L.; Polyak, L.; White, J.W.C.

2010-01-01

Paleoclimatic records show that the GreenlandIce Sheet consistently has lost mass in response to warming, and grown in response to cooling. Such changes have occurred even at times of slow or zero sea-level change, so changing sea level cannot have been the cause of at least some of the ice-sheet changes. In contrast, there are no documented major ice-sheet changes that occurred independent of temperature changes. Moreover, snowfall has increased when the climate warmed, but the ice sheet lost mass nonetheless; increased accumulation in the ice sheet's center has not been sufficient to counteract increased melting and flow near the edges. Most documented forcings and ice-sheet responses spanned periods of several thousand years, but limited data also show rapid response to rapid forcings. In particular, regions near the ice margin have responded within decades. However, major changes of central regions of the ice sheet are thought to require centuries to millennia. The paleoclimatic record does not yet strongly constrain how rapidly a major shrinkage or nearly complete loss of the ice sheet could occur. The evidence suggests nearly total ice-sheet loss may result from warming of more than a few degrees above mean 20th century values, but this threshold is poorly defined (perhaps as little as 2 °C or more than 7 °C). Paleoclimatic records are sufficiently sketchy that the ice sheet may have grown temporarily in response to warming, or changes may have been induced by factors other than temperature, without having been recorded.

Triggering of explosive reconnection in a thick current sheet via current sheet compression: Less current sheet thinning, more temperature anisotropy

NASA Astrophysics Data System (ADS)

Shimizu, K.; Shinohara, I.; Fujimoto, M.

2016-12-01

Two-dimensional kinetic simulations of compression of thick current sheets are performed to see how it can lead to triggering of explosive magnetic reconnection. The current sheet under study is simply in a Harris-like anti-paralell and symmetric geometry. A one-dimensional pre-study shows that the compression is more effective to make the plasma anisotropy than to thin the current sheet width. When the lobe magnetic field is amplified by a factor of 2, the plasma temperature anisotropy inside the current sheet reaches 2 but the current sheet thickness is reduced only by 1/sqrt(2). If a current sheet thickness needs to be comparable to the ion inertial scale for reconnection triggering take place, as is widely and frequently mentioned in the research community, the initial thickness cannot be more than a few ion scale for reconnection to set-in. On the other hand, the temperature anisotropy of 2 can be significant for the triggering problem. Two-dimensional simulations show explosive magnetic reconnection to take place even when the initial current sheet thickness more than an order of magnitude thicker than the ion scale, indicating the resilient triggering drive supplied by the temperature anisotropy. We also discuss how the reconnection triggering capability of the temperature anisotropy boosted tearing mode for thick current sheets compares with the instabilities in the plane orthogonal to the reconnecting field.

3D modelling of the Tejeda Caldera cone-sheet swarm, Gran Canaria, Canary Islands, Spain

NASA Astrophysics Data System (ADS)

Samrock, Lisa K.; Jensen, Max J.; Burchardt, Steffi; Troll, Valentin R.; Mattsson, Tobias; Geiger, Harri

2015-04-01

Cone-sheet swarms provide vital information on the interior of volcanic systems and their plumbing systems (e.g. Burchardt et al. 2013). This information is important for the interpretation of processes and dynamics of modern and ancient volcanic systems, and is therefore vital for assessing volcanic hazards and to reduce risks to modern society. To more realistically model cone-sheet emplacement an approximation of their 3D shape needs to be known. Most cone-sheet swarms are not sufficiently exposed laterally and/or vertically, however, which makes it difficult to determine the geometry of a cone-sheet swarm at depth, especially since different shapes (e.g. convex, straight or concave continuations) would produce a similar trace at the surface (cf. Burchardt et al. 2011, and references therein). The Miocene Tejeda Caldera on Gran Canaria, Canary Islands, Spain, hosts a cone-sheet swarm that was emplaced into volcaniclastic caldera infill at about 12.3-7.3 Ma (Schirnick et al. 1999). The dyke swarm displays over 1000 m of vertical exposure and more than 15 km of horizontal exposure, making it a superb locality to study the evolution of cone-sheet swarms in detail and to determine its actual geometry in 3D space. We have used structural data of Schirnick (1996) to model the geometry of the Tejeda cone-sheet in 3D, using the software Move® by Midland Valley Ltd. Based on previous 2D projections, Schirnick et al. (1999) suggested that the cone-sheet swarm is formed by a stack of parallel intrusive sheets which have a truncated dome geometry and form a concentric structure around a central axis, assuming straight sheet-intrusions. Our 3D model gives insight into the symmetries of the sheets and the overall geometry of the cone-sheet swarm below the surface. This visualization now allows to grasp the complexity of the Tejeda cone-sheet swarm at depth, particularly in relation to different possible cone-sheet geometries suggested in the literature (cf. Burchardt et al. 2011, and references therein), and we discuss the implications of this architecture for the feeding system of the Tejeda volcano and the associated temporal variations of cone-sheet emplacement. References: Burchardt, S., Tanner, D.C., Troll, V.R., Krumbholz, M., Gustafsson, L.E. (2011) Three-dimensional geometry of concentric intrusive sheet swarms in the Geitafell and the Dyrfjöll volcanoes, eastern Iceland. Geochemistry, Geophysics, Geosystems 12(7): Q0AB09. Burchardt, S., Troll, V.R., Mathieu, L., Emeleus, H.C., Donaldson, C.H. (2013) Ardnamruchan 3D cone-sheet architecture explained by a single elongate magma chamber. Scientific Reports 3:2891. Schirnick, C. (1996) Formation of an intracaldera cone sheet dike swarm (Tejeda Caldera, Gran Canaria) (Dissertation). Christian-Albrechts-Universität, Kiel, Germany. Schirnick, C., van den Bogaard, P., Schmincke, H.-U. (1999) Cone-sheet formation and intrusive growth of an oceanic island - The Miocene Tejeda complex on Gran Canaria (Canary Islands). Geology, 27: 207-210.

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet...

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet...

40 CFR 426.20 - Applicability; description of the sheet glass manufacturing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... sheet glass manufacturing subcategory. 426.20 Section 426.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Sheet Glass Manufacturing Subcategory § 426.20 Applicability; description of the sheet glass...

40 CFR 426.20 - Applicability; description of the sheet glass manufacturing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... sheet glass manufacturing subcategory. 426.20 Section 426.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Sheet Glass Manufacturing Subcategory § 426.20 Applicability; description of the sheet glass...

49 CFR 224.5 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., as where a layer of paint or dense chemical residue blocks all incoming light); this term does not... of American Railroads. Unqualified Retroreflective Sheeting means engineering grade sheeting, super engineering grade sheeting (enclosed lens) or high-intensity type sheeting (ASTM Type I, II, III, or IV...

Efficacy of a polyurethane dressing versus a soft silicone sheet on hypertrophic scars.

PubMed

Wigger-Albert, W; Kuhlmann, M; Wilhelm, D; Mrowietz, U; Eichhorn, K; Ortega, J; Bredehorst, A; Wilhelm, K-P

2009-05-01

To compare the efficacy and safety of a polyurethane dressing with a silicone sheet in the treatment of hypertrophic scars. Sixty patients participated in this intra-individual 12-week clinical trial. Each scar was divided into two areas, to which the polyurethane dressing and the silicone sheet were randomly allocated. The primary outcome measure was the percentage change in the overall scar index (SI) between baseline and week 12. Secondary outcome measures included changes in skin redness, objectively measured by chromametry, and patients views on the aesthetic outcome of treatment. Both therapies achieved favourable results for all of the above outcome measures. Results were comparable for the primary outcome measure: 29.4% versus 33.7% for the silicone sheet and polyurethane product respectively. The decrease in the overall SI was significantly more pronounced for the polyurethane product after week 4 (5.6% versus 15.8% for the silicone sheet; p<0.0001) and week 8 (20.2% versus 27.1%; p=0.012). Both regimens were associated with a significant reduction in the clinical signs of hypertrophic scars over 12 weeks of treatment. The polyurethane dressing demonstrated a significantly more pronounced reduction in severity of these clinical signs after four and eight weeks of treatment and was better tolerated than the silicone sheet. l This study was funded by Beiersdorf AG. proDERM is an independent research company, and none of the authors have an interest in the sponsors commercial activities.

Provenance of Des Moines lobe till records ice-stream catchment evolution during Laurentide deglaciation

USGS Publications Warehouse

Lusardi, B.A.; Jennings, C.E.; Harris, K.L.

2011-01-01

Mapping and analysis of deposits of the Des Moines lobe of the Laurentide Ice Sheet, active after the Last Glacial Maximum (LGM), reveal several texturally and lithologically distinct tills within what had been considered to be a homogeneous deposit. Although the differences between tills are subtle, minor distinctions are predictable and mappable, and till sheets within the area covered by the lobe can be correlated for hundreds of kilometres parallel to ice flow. Lateral till-sheet contacts are abrupt or overlap in a narrow zone, coincident with a geomorphic discontinuity interpreted to be a shear margin. Till sheets 10 to 20m thick show mixing in their lower 2 to 3m. We suggest that: (i) lithologically distinct till sheets correspond to unique ice-stream source areas; (ii) the sequence of tills deposited by the Des Moines lobe was the result of the evolution and varying dominance of nearby and competing ice streams and their tributaries; and (iii) in at least one instance, more than one ice stream simultaneously contributed to the lobe. Therefore the complex sequence of tills of subtly different provenances, and the unconformities between them record the evolution of an ice-catchment area during Laurentide Ice Sheet drawdown. Till provenance data suggest that, after till is created in the ice-stream source area, the subglacial conditions required for transporting till decline and incorporation of new material is limited. ?? 2011 The Authors. Boreas ?? 2011 The Boreas Collegium.

Development of a highly transparent superamphiphobic plastic sheet by nanoparticle and chemical coating.

PubMed

Wong, Ten It; Wang, Hao; Wang, Fuke; Sin, Sau Leng; Quan, Cheng Gen; Wang, Shi Jie; Zhou, Xiaodong

2016-04-01

A highly transparent superamphiphobic plastic sheet was developed. The plastic sheet polymethyl methacrylate (PMMA) was spin-coated on a glass substrate. Synthesized silica nanoparticles were sprayed on PMMA, followed by fluorosilane drop-coating. The results of contact angle measurements show that the developed PMMA sheet has superamphiphobic properties with high advancing contact angles for water (154°), toluene (139°), and silicone oil (132.9°). The amphiphobicity of the plastic sheet can be tuned by the surface coverage of the silica nanoparticles distributed on the PMMA surface. The surface coverage of the nanoparticles on our PMMA sheet is about 20%, and it agrees with our contact angle calculations for the sheet with and without nanoparticles. Copyright © 2016 Elsevier Inc. All rights reserved.

Dynamics of Radially Expanding Liquid Sheets

NASA Astrophysics Data System (ADS)

Majumdar, Nayanika; Tirumkudulu, Mahesh S.

2018-04-01

The process of atomization often involves ejecting thin liquid sheets at high speeds from a nozzle that causes the sheet to flap violently and break up into fine droplets. The flapping of the liquid sheet has long been attributed to the sheet's interaction with the surrounding gas phase. Here, we present experimental evidence to the contrary and show that the flapping is caused by the thinning of the liquid sheet as it spreads out from the nozzle exit. The measured growth rates of the waves agree remarkably well with the predictions of a recent theory that accounts for the sheet's thinning but ignores aerodynamic interactions. We anticipate these results to not only lead to more accurate predictions of the final drop-size distribution but also enable more efficient designs of atomizers.

Interhemispheric ice-sheet synchronicity during the last glacial maximum

USGS Publications Warehouse

Weber, Michael E.; Clark, Peter U.; Ricken, Werner; Mitrovica, Jerry X.; Hostetler, Steven W.; Kuhn, Gerhard

2011-01-01

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood. We develop a chronology for the Weddell Sea sector of the East Antarctic Ice Sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates that the advance to and retreat from their maximum extent was within dating uncertainties synchronous with most sectors of Northern Hemisphere ice sheets. Surface climate forcing of Antarctic mass balance would probably cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Our new data support teleconnections involving sea-level forcing from Northern Hemisphere ice sheets and changes in North Atlantic deep-water formation and attendant heat flux to Antarctic grounding lines to synchronize the hemispheric ice sheets.

Interhemispheric ice-sheet synchronicity during the Last Glacial Maximum.

PubMed

Weber, Michael E; Clark, Peter U; Ricken, Werner; Mitrovica, Jerry X; Hostetler, Steven W; Kuhn, Gerhard

2011-12-02

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood. We develop a chronology for the Weddell Sea sector of the East Antarctic Ice Sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates that the advance to and retreat from their maximum extent was within dating uncertainties synchronous with most sectors of Northern Hemisphere ice sheets. Surface climate forcing of Antarctic mass balance would probably cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Our new data support teleconnections involving sea-level forcing from Northern Hemisphere ice sheets and changes in North Atlantic deep-water formation and attendant heat flux to Antarctic grounding lines to synchronize the hemispheric ice sheets.

Interhemispheric ice-sheet synchronicity during the Last Glacial Maximum

NASA Astrophysics Data System (ADS)

Weber, M. E.; Clark, P. U.; Ricken, W.; Mitrovica, J. X.; Hostetler, S. W.; Kuhn, G.

2012-04-01

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood because only a few findings with robust chronologies exist for Antarctic ice sheets. We developed a chronology for the Weddell Sea sector of the East Antarctic ice sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates the advance to their maximum extent at 29 -28 ka, and retreat from their maximum extent at 19 ka was nearly synchronous with Northern Hemisphere ice sheets (Weber, M.E., Clark, P. U., Ricken, W., Mitrovica, J. X., Hostetler, S. W., and Kuhn, G. (2011): Interhemispheric ice-sheet synchronicity during the Last Glacial Maximum. - Science, 334, 1265-1269, doi: 10.1126:science.1209299). As for the deglaciation, modeling studies suggest a late ice-sheet retreat starting around 14 ka BP and ending around 7 ka BP with a large impact of an unstable West Antarctic Ice Sheet (WAIS) and a small impact of a stable East Antarctic Ice Sheet (EAIS). However, the Weddell Sea sites studied here, as well as sites from the Scotia Sea, provide evidence that specifically the EAIS responded much earlier, possibly provided a significant contribution to the last sea-level rise, and was much more dynamic than previously thought. Using the results of an atmospheric general circulation we conclude that surface climate forcing of Antarctic ice mass balance would likely cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Furthermore, our new data support teleconnections involving a sea-level fingerprint forced from Northern Hemisphere ice sheets as indicated by gravitational modeling. Also, changes in North Atlantic Deepwater formation and attendant heat flux to Antarctic grounding lines may have contributed to synchronizing the hemispheric ice sheets.

Rotator cuff repair using cell sheets derived from human rotator cuff in a rat model.

PubMed

Harada, Yoshifumi; Mifune, Yutaka; Inui, Atsuyuki; Sakata, Ryosuke; Muto, Tomoyuki; Takase, Fumiaki; Ueda, Yasuhiro; Kataoka, Takeshi; Kokubu, Takeshi; Kuroda, Ryosuke; Kurosaka, Masahiro

2017-02-01

To achieve biological regeneration of tendon-bone junctions, cell sheets of human rotator-cuff derived cells were used in a rat rotator cuff injury model. Human rotator-cuff derived cells were isolated, and cell sheets were made using temperature-responsive culture plates. Infraspinatus tendons in immunodeficient rats were resected bilaterally at the enthesis. In right shoulders, infraspinatus tendons were repaired by the transosseous method and covered with the cell sheet (sheet group), whereas the left infraspinatus tendons were repaired in the same way without the cell sheet (control group). Histological examinations (safranin-O and fast green staining, isolectin B4, type II collagen, and human-specific CD31) and mRNA expression (vascular endothelial growth factor; VEGF, type II collagen; Col2, and tenomodulin; TeM) were analyzed 4 weeks after surgery. Biomechanical tests were performed at 8 weeks. In the sheet group, proteoglycan at the enthesis with more type II collagen and isolectin B4 positive cells were seen compared with in the control group. Human specific CD31-positive cells were detected only in the sheet group. VEGF and Col2 gene expressions were higher and TeM gene expression was lower in the sheet group than in the control group. In mechanical testing, the sheet group showed a significantly higher ultimate failure load than the control group at 8 weeks. Our results indicated that the rotator-cuff derived cell sheet could promote cartilage regeneration and angiogenesis at the enthesis, with superior mechanical strength compared with the control. Treatment for rotator cuff injury using cell sheets could be a promising strategy for enthesis of tendon tissue engineering. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:289-296, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

A recipe for designing water-soluble, beta-sheet-forming peptides.

PubMed Central

Mayo, K. H.; Ilyina, E.; Park, H.

1996-01-01

Based on observations of solubility and folding properties of peptide 33-mers derived from the beta-sheet domains of platelet factor-4 (PF4), interleukin-8 (IL-8), and growth related protein (Gro-alpha), as well as other beta-sheet-forming peptides, general guidelines have been developed to aid in the design of water soluble, self-association-induced beta-sheet-forming peptides. CD, 1H-NMR, and pulsed field gradient NMR self-diffusion measurements have been used to assess the degree of folding and state of aggregation. PF4 peptide forms native-like beta-sheet tetramers and is sparingly soluble above pH 6. IL-8 peptide is insoluble between pH 4.5 and pH 7.5, yet forms stable, native-like beta-sheet dimers at higher pH. Gro-alpha peptide is soluble at all pH values, yet displays no discernable beta-sheet structure even when diffusion data indicate dimer-tetramer aggregation. A recipe used in the de novo design of water-soluble beta-sheet-forming peptides calls for the peptide to contain 40-50% hydrophobic residues, usually aliphatic ones (I, L, V, A, M) (appropriately paired and mostly but not always alternating with polar residues in the sheet sequence), a positively charged (K, R) to negatively charged (E, D) residue ratio between 4/2 and 6/2, and a noncharged polar residue (N, Q, T, S) composition of about 20% or less. Results on four de novo designed, 33-residue peptides are presented supporting this approach. Under near physiologic conditions, all four peptides are soluble, form beta-sheet structures to varying degrees, and self-associate. One peptide folds as a stable, compact beta-sheet tetramer, whereas the others are transient beta-sheet-containing aggregates. PMID:8819163

Ice sheet climate modeling: past achievements, ongoing challenges, and future endeavors

NASA Astrophysics Data System (ADS)

Lenaerts, J.

2017-12-01

Fluctuations in surface mass balance (SMB) mask out a substantial portion of contemporary Greenland and Antarctic ice sheet mass loss. That implies that we need accurate, consistent, and long-term SMB time series to isolate the mass loss signal. This in turn requires understanding of the processes driving SMB, and how they interplay. The primary controls on present-day ice sheet SMB are snowfall, which is regulated by large-scale atmospheric variability, and surface meltwater production at the ice sheet's edges, which is a complex result of atmosphere-surface interactions. Additionally, wind-driven snow redistribution and sublimation are large SMB contributors on the downslope areas of the ice sheets. Climate models provide an integrated framework to simulate all these individual ice sheet components. Recent developments in RACMO2, a regional climate model bound by atmospheric reanalyses, have focused on enhancing horizontal resolution, including blowing snow, snow albedo, and meltwater processes. Including these physics not only enhanced our understanding of the ice sheet climate system, but also enabled to obtain increasingly accurate estimates of ice sheet SMB. However, regional models are not suitable to capture the mutual interactions between ice sheet and the remainder of the global climate system in transient climates. To take that next step, global climate models are essential. In this talk, I will highlight our present work on improving ice sheet climate in the Community Earth System Model (CESM). In particular, we focus on an improved representation of polar firn, ice sheet clouds, and precipitation. For this exercise, we extensively use field observations, remote sensing data, as well as RACMO2. Next, I will highlight how CESM is used to enhance our understanding of ice sheet SMB, its drivers, and past and present changes.

Using an extreme bony prominence anatomical model to examine the influence of bed sheet materials and bed making methods on the distribution of pressure on the support surface.

PubMed

Iuchi, Terumi; Nakajima, Yukari; Fukuda, Moriyoshi; Matsuo, Junko; Okamoto, Hiroyuki; Sanada, Hiromi; Sugama, Junko

2014-05-01

Bed sheets generate high surface tension across the support surface and increase pressure to the body through a process known as the hammock effect. Using an anatomical model and a loading device characterized by extreme bony prominences, the present study compared pressure distributions on support surfaces across different bed making methods and bed sheet materials to determine the factors that influence pressure distribution. The model was placed on a pressure mapping system (CONFORMat; NITTA Corp., Osaka, Japan), and interface pressure was measured. Bed sheet elasticity and friction between the support surface and the bed sheets were also measured. For maximum interface pressure, the relative values of the following methods were higher than those of the control method, which did not use any bed sheets: cotton sheets with hospital corners (1.28, p = 0.02), polyester with no corners (1.29, p = 0.01), cotton with no corners (1.31, p = 0.003), and fitted polyester sheets (1.35, p = 0.002). Stepwise multiple regression analysis indicated that maximum interface pressure was negatively correlated with bed sheet elasticity (R(2) = 0.74). A statistically significant negative correlation was observed between maximum interface pressure and immersion depth, which was measured using the loading device (r = -0.40 and p = 0.04). We found that several combinations of bed making methods and bed sheet materials induced maximum interface pressures greater than those observed for the control method. Bed sheet materials influenced maximum interface pressure, and bed sheet elasticity was particularly important in reducing maximum interface pressure. Copyright © 2014 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Exploring the Moon: A teacher's guide with activities for Earth and space sciences

NASA Technical Reports Server (NTRS)

Taylor, G. Jeffrey; Martel, Linda M. V.; Bays, Brooks G., Jr.

1994-01-01

This guide contains educational materials designed for use in upper elementary through high schools with the Lunar Sample Disk. A set of thirty-six 35-mm slides complements the activities in this guidebook. The book contains: (1) information on the Lunar Sample Disk; (2) a curriculum content matrix; (3) a teacher's guide; (4) moon ABC's fact sheet; (5) rock ABC's fact sheet; (6) progress in Lunar Science chart; (7) seventeen activities; (8) a resource section for each unit; (9) a glossary; and (10) a list of NASA educational resources.

A statistical study of the inner edge of the electron plasma sheet and the net convection potential as a function of geomagnetic activity

NASA Astrophysics Data System (ADS)

Jiang, F.; Kivelson, M. G.; Walker, R. J.; Khurana, K. K.; Angelopoulos, V.; Hsu, T.

2011-06-01

A widely accepted explanation of the location of the inner edge of the electron plasma sheet and its dependence on electron energy is based on drift motions of individual particles. The boundary is identified as the separatrix between drift trajectories linking the tail to the dayside magnetopause (open paths) and trajectories closed around the Earth. A statistical study of the inner edge of the electron plasma sheet using THEMIS Electrostatic Analyzer plasma data from November 2007 to April 2009 enabled us to examine this model. Using a dipole magnetic field and a Volland-Stern electric field with shielding, we find that a steady state drift boundary model represents the average location of the electron plasma sheet boundary and reflects its variation with the solar wind electric field in the local time region between 21:00 and 06:00, except at high activity levels. However, the model does not reproduce the observed energy dispersion of the boundaries. We have also used the location of the inner edge of the electron plasma sheet to parameterize the potential drop of the tail convection electric field as a function of solar wind electric field (Esw) and geomagnetic activity. The range of Esw examined is small because the data were acquired near solar minimum. For the range of values tested (meaningful statistics only for Esw < 2 mV/m), reasonably good agreement is found between the potential drop of the tail convection electric field inferred from the location of the inner edge and the polar cap potential drop calculated from the model of Boyle et al. (1997).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jozsef, G

Purpose: To build a test device for HDR afterloaders capable of checking source positions, times at positions and estimate the activity of the source. Methods: A catheter is taped on a plastic scintillation sheet. When a source travels through the catheter, the scintillator sheet lights up around the source. The sheet is monitored with a video camera, and records the movement of the light spot. The center of the spot on each image on the video provides the source location, and the time stamps of the images can provide the dwell time the source spend in each location. Finally, themore » brightness of the light spot is related to the activity of the source. A code was developed for noise removal, calibrate the scale of the image to centimeters, eliminate the distortion caused by the oblique view angle, identifying the boundaries of the light spot, transforming the image into binary and detect and calculate the source motion, positions and times. The images are much less noisy if the camera is shielded. That requires that the light spot is monitored in a mirror, rather than directly. The whole assembly is covered from external light and has a size of approximately 17×35×25cm (H×L×W) Results: A cheap camera in BW mode proved to be sufficient with a plastic scintillator sheet. The best images were resulted by a 3mm thick sheet with ZnS:Ag surface coating. The shielding of the camera decreased the noise, but could not eliminate it. A test run even in noisy condition resulted in approximately 1 mm and 1 sec difference from the planned positions and dwell times. Activity tests are in progress. Conclusion: The proposed method is feasible. It might simplify the monthly QA process of HDR Brachytherapy units.« less

Effect of dialyzer geometry on granulocyte and complement activation.

PubMed

Schaefer, R M; Heidland, A; Hörl, W H

1987-01-01

During hemodialysis with cuprophan membranes, the complement system as well as leukocytes become activated. In order to clarify the role of dialyzer geometry, the effect of hollow-fiber versus flat-sheet dialyzers and of different surface areas on C3a generation and leukocyte degranulation was investigated. Plasma levels of leukocyte elastase in complex with alpha 1-proteinase inhibitor were significantly increased after 1 h (+55%) and 3 h (+62%) of hemodialysis with flat-sheet dialyzers as compared to hollow-fiber devices. In addition, plasma levels of lactoferrin, released from the specific granules of leukocytes during activation, were significantly higher (+42%) 3 h after the onset of dialysis treatment with flat-sheet than with hollow-fiber dialyzers. With respect to surface area, larger dialyzers tended to cause more release of leukocyte elastase as compared to dialyzers with smaller surface areas, irrespectively of the configuration of the dialyzer used. On the other hand, activation of the complement system, as measured by the generation of C3a-desarg, did not differ with both types of configurations. The same held true for leukopenia, which was almost identical for hollow-fiber and flat-sheet dialyzers. From these findings two lines of evidence emerge: First, not only the type of membrane material used in a dialyzer may influence its biocompatibility, but the geometry of the extracorporeal device also determines the degree of compatibility. Hence, the extent of leukocyte activation correlated with both configuration of the dialyzer and surface area of the membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Estimating the impact of internal climate variability on ice sheet model simulations

NASA Astrophysics Data System (ADS)

Tsai, C. Y.; Forest, C. E.; Pollard, D.

2016-12-01

Rising sea level threatens human societies and coastal habitats and melting ice sheets are a major contributor to sea level rise (SLR). Thus, understanding uncertainty of both forcing and variability within the climate system is essential for assessing long-term risk of SLR given their impact on ice sheet evolution. The predictability of polar climate is limited by uncertainties from the given forcing, the climate model response to this forcing, and the internal variability from feedbacks within the fully coupled climate system. Among those sources of uncertainty, the impact of internal climate variability on ice sheet changes has not yet been robustly assessed. Here we investigate how internal variability affects ice sheet projections using climate fields from two Community Earth System Model (CESM) large-ensemble (LE) experiments to force a three-dimensional ice sheet model. Each ensemble member in an LE experiment undergoes the same external forcings but with unique initial conditions. We find that for both LEs, 2m air temperature variability over Greenland ice sheet (GrIS) can lead to significantly different ice sheet responses. Our results show that the internal variability from two fully coupled CESM LEs can cause about 25 35 mm differences of GrIS's contribution to SLR in 2100 compared to present day (about 20% of the total change), and 100m differences of SLR in 2300. Moreover, only using ensemble-mean climate fields as the forcing in ice sheet model can significantly underestimate the melt of GrIS. As the Arctic region becomes warmer, the role of internal variability is critical given the complex nonlinear interactions between surface temperature and ice sheet. Our results demonstrate that internal variability from coupled atmosphere-ocean general circulation model can affect ice sheet simulations and the resulting sea-level projections. This study highlights an urgent need to reassess associated uncertainties of projecting ice sheet loss over the next few centuries to obtain robust estimates of the contribution of ice sheet melt to SLR.

A Statistical Model of the Magnetotail Neutral Sheet

NASA Astrophysics Data System (ADS)

Xiao, Sudong; Zhang, Tielong; Baumjohann, Wolfgang; Nakamura, Rumi; Ge, Yasong; Du, Aimin; Wang, Guoqiang; Lu, Quanming

2015-04-01

The neutral sheet of the magnetotail is characterized by weak magnetic field, strong cross tail current, and a reversal of the magnetic field direction across it. The dynamics of the earth's magnetosphere is greatly influenced by physical processes that occur near the neutral sheet. However, the exact position of the neutral sheet is variable in time. It is therefore essential to have a reliable estimate of the average position of the neutral sheet. Magnetic field data from ten years of Cluster, nineteen years of Geotail, four years of TC 1, and seven years of THEMIS observations have been incorporated to obtain a model of the magnetotail neutral sheet. All data in aberrated GSM (Geocentric Solar Magnetospheric) coordinate system are normalized to the same solar wind pressure condition. The shape and position of the neutral sheet, illustrated directly by the separator of positive and negative Bx on the YZ cross sections, are fitted with a displaced ellipse model. It is consistent with previous studies that the neutral sheet becomes curvier in the YZ cross section when the dipole tilt increases, yet our model shows the curviest neutral sheet compared with previous models. The new model reveals a hinging distance very close to 10 RE at a reference solar wind dynamic pressure of 2 nPa. We find that the earth dipole tilt angle not only affects the neutral sheet configuration in the YZ cross section but also in the XZ cross section. The neutral sheet becomes more tilting in the XZ cross section when the dipole tilt increases. The effect of an interplanetary magnetic field (IMF) penetration is studied, and an IMF By-related twisting of about 3° is found. Anticlockwise twisting of the neutral sheet is observed, looking along the downtail direction, for a positive IMF By, and clockwise twisting of the neutral sheet for a negative IMF By.

Probability based hydrologic catchments of the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Hudson, B. D.

2015-12-01

Greenland Ice Sheet melt water impacts ice sheet flow dynamics, fjord and coastal circulation, and sediment and biogeochemical fluxes. Melt water exiting the ice sheet also is a key term in its mass balance. Because of this, knowledge of the area of the ice sheet that contributes melt water to a given outlet (its hydrologic catchment) is important to many ice sheet studies and is especially critical to methods using river runoff to assess ice sheet mass balance. Yet uncertainty in delineating ice sheet hydrologic catchments is a problem that is rarely acknowledged. Ice sheet catchments are delineated as a function of both basal and surface topography. While surface topography is well known, basal topography is less certain because it is dependent on radar surveys. Here, I a present a Monte Carlo based approach to delineating ice sheet catchments that quantifies the impact of uncertain basal topography. In this scheme, over many iterations I randomly vary the ice sheet bed elevation within published error bounds (using Morlighem et al., 2014 bed and bed error datasets). For each iteration of ice sheet bed elevation, I calculate the hydraulic potentiometric surface and route water over its path of 'steepest' descent to delineate the catchment. I then use all realizations of the catchment to arrive at a probability map of all major melt water outlets in Greenland. I often find that catchment size is uncertain, with small, random perturbations in basal topography leading to large variations in catchments size. While some catchments are well defined, others can double or halve in size within published basal topography error bars. While some uncertainty will likely always remain, this work points to locations where studies of ice sheet hydrology would be the most successful, allows reinterpretation of past results, and points to where future radar surveys would be most advantageous.

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet...

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet...

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet...

49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

Code of Federal Regulations, 2012 CFR

2012-10-01

... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

Code of Federal Regulations, 2014 CFR

2014-10-01

... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

Code of Federal Regulations, 2013 CFR

2013-10-01

... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

Code of Federal Regulations, 2011 CFR

2011-10-01

... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

47 CFR 32.3000 - Instructions for balance sheet accounts-Depreciation and amortization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Instructions for balance sheet accounts-Depreciation and amortization. 32.3000 Section 32.3000 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... for Balance Sheet Accounts § 32.3000 Instructions for balance sheet accounts—Depreciation and...

47 CFR 32.3000 - Instructions for balance sheet accounts-Depreciation and amortization.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Instructions for balance sheet accounts-Depreciation and amortization. 32.3000 Section 32.3000 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... for Balance Sheet Accounts § 32.3000 Instructions for balance sheet accounts—Depreciation and...

75 FR 45144 - Recovery Fact Sheet 9580.203, Debris Monitoring

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-02

...] Recovery Fact Sheet 9580.203, Debris Monitoring AGENCY: Federal Emergency Management Agency, DHS. ACTION... accepting comments on Recovery Fact Sheet 9580.203, Debris Monitoring. DATES: Comments must be received by... guidelines. Specifically, the fact sheet provides information on debris monitoring roles and responsibilities...

49 CFR 236.338 - Mechanical locking required in accordance with locking sheet and dog chart.

Code of Federal Regulations, 2010 CFR

2010-10-01

... locking sheet and dog chart. 236.338 Section 236.338 Transportation Other Regulations Relating to... in accordance with locking sheet and dog chart. Mechanical locking shall be in accordance with locking sheet and dog chart currently in effect. ...

ICESat's First Year of Measurements Over the Polar Ice Sheets

NASA Astrophysics Data System (ADS)

Shuman, C. A.

2004-05-01

NASA's Ice, Cloud and Land Elevation Satellite (ICESat) mission was developed to measure changes in elevation of the Greenland and Antarctic ice sheets. Its primary mission goal is to significantly refine estimates of polar ice sheet mass balance. Obtaining precise, spatially dense, ice sheet elevations through time is the first step towards this goal. ICESat data will then enable study of associations between observed ice changes and dynamic or climatic forcing factors, and thus enable improved estimation of the present and future contributions of the ice sheets to global sea level rise. ICESat was launched on January 12, 2003 and acquired science data from February 20th to March 29th with the first of the three lasers of the Geoscience Laser Altimeter System (GLAS). Data acquisition with the second laser began on September 25th and continued until November 18th, 2003. For one-year change detection, the second laser is scheduled for operation from approximately February 17th to March 20th, 2004. Additional operational periods will be selected to 1) enable periodic measurements through the year, and 2) to support of other NASA Earth Science Enterprise missions and activities. To obtain these precise ice sheet elevations, GLAS has a 1064 nm wavelength laser operating at 40 Hz with a designed range precision of about 10 cm. The laser footprints are about 70 m in diameter on the Earth's surface and are spaced every 172 m along-track. The on-board GPS receiver enables radial orbit determinations to an accuracy better than 5 cm. The star-tracking attitude-determination system will enable laser footprints to be located to 6 m horizontally when attitude calibration is completed. The orbital altitude averages 600 km at an inclination of 94 degrees with coverage extending from 86 degrees N and S latitude. The spacecraft attitude can be controlled to point the laser beam to within 50 m of surface reference tracks over the ice sheets and to point off-nadir up to 5 degrees to targets of interest. ICESat was designed to operate for 3 to 5 years but laser lifetime is uncertain and may not achieve this goal based on a detailed review following the failure of Laser 1. However, the results from the first full year of ICESat operations demonstrate that the GLAS instrument can measure ice sheet elevations with unprecedented accuracy. This presentation will show ice sheet results using crossover and exact repeat track analyses. Additional data using the remaining lasers will further demonstrate the capability to measure ice sheet elevation changes and improve mass balance assessments of the great polar ice sheets.

Method and apparatus for assessing material properties of sheet-like materials

DOEpatents

Telschow, Kenneth L.; Deason, Vance A.

2002-01-01

Apparatus for producing an indication of a material property of a sheet-like material according to the present invention may comprise an excitation source for vibrating the sheet-like material to produce at least one traveling wave therein. A light source configured to produce an object wavefront and a reference wavefront directs the object wavefront toward the sheet-like material to produce a modulated object wavefront. A modulator operatively associated with the reference wavefront modulates the reference wavefront in synchronization with the traveling wave on the sheet-like material to produce a modulated reference wavefront. A sensing medium positioned to receive the modulated object wavefront and the modulated reference wavefront produces an image of the traveling wave in the sheet-like material, the image of the anti-symmetric traveling wave being related to a displacement amplitude of the anti-symmetric traveling wave over a two-dimensional area of the vibrating sheet-like material. A detector detects the image of the traveling wave in the sheet-like material.

Stability of Thin Liquid Sheet Flows

NASA Technical Reports Server (NTRS)

McConley, Marc W.; Chubb, Donald L.; McMaster, Matthew S.; Afjeh, Abdollah A.

1997-01-01

A two-dimensional, linear stability analysis of a thin nonplanar liquid sheet flow in vacuum is carried out. A sheet flow created by a narrow slit of W and tau attains a nonplanar cross section as a consequence of cylinders forming on the sheet edge under the influence of surface tension forces. The region where these edge cylinders join the sheet is one of high curvature, and this is found to be the location where instability is most likely to occur. The sheet flow is found to be unstable, but with low growth rates for symmetric wave disturbances and high growth rates for antisymmetric disturbances. By combining the symmetric and antisymmetric disturbance modes, a wide range of stability characteristics is obtained. The product of unstable growth rate and flow time is proportional to the width-to-thickness ratio of the sift generating the sheet Three-dimensional effects can alter these results, particularly when the sheet length-to-width ratio is not much greater than unity.

Research on Al-alloy sheet forming formability during warm/hot sheet hydroforming based on elliptical warm bulging test

NASA Astrophysics Data System (ADS)

Cai, Gaoshen; Wu, Chuanyu; Gao, Zepu; Lang, Lihui; Alexandrov, Sergei

2018-05-01

An elliptical warm/hot sheet bulging test under different temperatures and pressure rates was carried out to predict Al-alloy sheet forming limit during warm/hot sheet hydroforming. Using relevant formulas of ultimate strain to calculate and dispose experimental data, forming limit curves (FLCS) in tension-tension state of strain (TTSS) area are obtained. Combining with the basic experimental data obtained by uniaxial tensile test under the equivalent condition with bulging test, complete forming limit diagrams (FLDS) of Al-alloy are established. Using a quadratic polynomial curve fitting method, material constants of fitting function are calculated and a prediction model equation for sheet metal forming limit is established, by which the corresponding forming limit curves in TTSS area can be obtained. The bulging test and fitting results indicated that the sheet metal FLCS obtained were very accurate. Also, the model equation can be used to instruct warm/hot sheet bulging test.

The Promiscuity of [beta]-Strand Pairing Allows for Rational Design of [beta]-Sheet Face Inversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makabe, Koki; Koide, Shohei

2009-06-17

Recent studies suggest the dominant role of main-chain H-bond formation in specifying {beta}-sheet topology. Its essentially sequence-independent nature implies a large degree of freedom in designing {beta}-sheet-based nanomaterials. Here we show rational design of {beta}-sheet face inversions by incremental deletions of {beta}-strands from the single-layer {beta}-sheet of Borrelia outer surface protein A. We show that a {beta}-sheet structure can be maintained when a large number of native contacts are removed and that one can design large-scale conformational transitions of a {beta}-sheet such as face inversion by exploiting the promiscuity of strand-strand interactions. High-resolution X-ray crystal structures confirmed the success ofmore » the design and supported the importance of main-chain H-bonds in determining {beta}-sheet topology. This work suggests a simple but effective strategy for designing and controlling nanomaterials based on {beta}-rich peptide self-assemblies.« less

Experimental realization of two-dimensional boron sheets

NASA Astrophysics Data System (ADS)

Feng, Baojie; Zhang, Jin; Zhong, Qing; Li, Wenbin; Li, Shuai; Li, Hui; Cheng, Peng; Meng, Sheng; Chen, Lan; Wu, Kehui

2016-06-01

A variety of two-dimensional materials have been reported in recent years, yet single-element systems such as graphene and black phosphorus have remained rare. Boron analogues have been predicted, as boron atoms possess a short covalent radius and the flexibility to adopt sp2 hybridization, features that favour the formation of two-dimensional allotropes, and one example of such a borophene material has been reported recently. Here, we present a parallel experimental work showing that two-dimensional boron sheets can be grown epitaxially on a Ag(111) substrate. Two types of boron sheet, a β12 sheet and a χ3 sheet, both exhibiting a triangular lattice but with different arrangements of periodic holes, are observed by scanning tunnelling microscopy. Density functional theory simulations agree well with experiments, and indicate that both sheets are planar without obvious vertical undulations. The boron sheets are quite inert to oxidization and interact only weakly with their substrate. We envisage that such boron sheets may find applications in electronic devices in the future.

Enhanced ice sheet melting driven by volcanic eruptions during the last deglaciation.

PubMed

Muschitiello, Francesco; Pausata, Francesco S R; Lea, James M; Mair, Douglas W F; Wohlfarth, Barbara

2017-10-24

Volcanic eruptions can impact the mass balance of ice sheets through changes in climate and the radiative properties of the ice. Yet, empirical evidence highlighting the sensitivity of ancient ice sheets to volcanism is scarce. Here we present an exceptionally well-dated annual glacial varve chronology recording the melting history of the Fennoscandian Ice Sheet at the end of the last deglaciation (∼13,200-12,000 years ago). Our data indicate that abrupt ice melting events coincide with volcanogenic aerosol emissions recorded in Greenland ice cores. We suggest that enhanced ice sheet runoff is primarily associated with albedo effects due to deposition of ash sourced from high-latitude volcanic eruptions. Climate and snowpack mass-balance simulations show evidence for enhanced ice sheet runoff under volcanically forced conditions despite atmospheric cooling. The sensitivity of past ice sheets to volcanic ashfall highlights the need for an accurate coupling between atmosphere and ice sheet components in climate models.

ISEE-1 and 2 observations of field-aligned currents in the distant midnight magnetosphere

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Kelly, T. J.; Russell, C. T.

1985-01-01

Magnetic field measurements obtained in the nightside magnetosphere by the co-orbiting ISEE-1 and 2 spacecraft have been examined for signatures of field-aligned currents (FAC). Such currents are found on the boundary of the plasma sheet both when the plasma sheet is expanding and when it is thinning. Evidence is often found for the existence of waves on the plasma sheet boundary, leading to multiple crossings of the FAC sheet. At times the boundary layer FAC sheet orientation is nearly parallel to the X-Z GSM plane, suggesting 'protrusions' of plasma sheet into the lobes. The boundary layer current polarity is, as expected, into the ionosphere in the midnight to dawn local time sector, and outward near dusk. Current sheet thicknesses and velocities are essentially independent of plasma sheet expansion or thinning, having typical values of 1500 km and 20-40 km/s respectively. Characteristic boundary layer current densities are about 10 nanoamps per square meter.

A Transient Initialization Routine of the Community Ice Sheet Model for the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

van der Laan, Larissa; van den Broeke, Michiel; Noël, Brice; van de Wal, Roderik

2017-04-01

The Community Ice Sheet Model (CISM) is to be applied in future simulations of the Greenland Ice Sheet under a range of climate change scenarios, determining the sensitivity of the ice sheet to individual climatic forcings. In order to achieve reliable results regarding ice sheet stability and assess the probability of future occurrence of tipping points, a realistic initial ice sheet geometry is essential. The current work describes and evaluates the development of a transient initialization routine, using NGRIP 18O isotope data to create a temperature anomaly field. Based on the latter, surface mass balance components runoff and precipitation are perturbed for the past 125k years. The precipitation and runoff fields originate from a downscaled 1 km resolution version of the regional climate model RACMO2.3 for the period 1961-1990. The result of the initialization routine is a present-day ice sheet with a transient memory of the last glacial-interglacial cycle, which will serve as the future runs' initial condition.

[Early prenatal interview: implementation of a sheet link "carried" by patient. The Aurore perinatal network experience].

PubMed

Dupont, C; Gonnaud, F; Touzet, S; Luciani, F; Perié, M-A; Molenat, F; Evrard, A; Fernandez, M-P; Roy, J; Rudigoz, R-C

2008-11-01

Early prenatal interview has needed the implementation of a new communication tool between follow-up pregnancy professionals: a link sheet filled and carried by patients. To assess the utilization of link sheet by trained professionals, the contribution of the interview and the patient acceptation of the link sheet. Descriptive survey from the database of link sheets returned by professionals to Aurore perinatal network and semi-guided interviews with 100 randomized patients. One thousand one hundred and nineteen link sheets were sent to Aurore perinatal network by 55 professionals out of 78 trained. For primipare, precocious prenatal interview contribution has concerned health care security (60%) and emotional security (56%). For multipare, this contribution has concerned mainly emotional security (80%). No interviewed patient has refused link sheet principle. Link sheet principle, like implemented by Aurore perinatal network, seems pertinent to professionals and patients but it constitutes only one of the elements of network elaboration of personalized care.

Supercritical fluid extraction of bi & multi-layer graphene sheets from graphite by using exfoliation technique

NASA Astrophysics Data System (ADS)

Xavier, Gauravi; Dave, Bhoomi; Khanna, Sakshum

2018-05-01

In recent times, researchers have turned to explore the possibility of using Supercritical Fluid (SCFs) system to penetrate into the inert-gaping of graphite and exfoliate it into a number of layer graphene sheets. The supercritical fluid holds excellent wetting surfaces with low interfacial tension and high diffusion coefficients. Although SCFs exfoliation approach looks promising to developed large scale & low-cost graphene sheet but has not received much attention. To arouse interest and reflection on this approach, this review is organized to summarize the recent progress in graphene production by SCF technology. Here we present the simplest route to obtained layers of graphene sheets by intercalating and exfoliating graphite using supercritical CO2 processing. The layers graphene nano-sheets were collected in dichloromethane (DCM) solution which prevents the restocking of sheets. The obtained graphene sheets show the desired characteristics and thus can be used in physical, chemical and biological sciences. Thus this method provides an effortless and eco-friendly approach for the synthesis of layers of graphene sheets.

Plasma Sheet Injections into the Inner Magnetosphere: Two-way Coupled OpenGGCM-RCM model results

NASA Astrophysics Data System (ADS)

Raeder, J.; Cramer, W. D.; Toffoletto, F.; Gilson, M. L.; Hu, B.

2017-12-01

Plasma sheet injections associated with low flux tube entropy bubbles have been found to be the primary means of mass transport from the plasma sheet to the inner magnetosphere. A two-way coupled global magnetosphere-ring current model, where the magnetosphere is modeled by the OpenGGCM MHD model and the ring current is modeled by the Rice Convection Model (RCM), is used to determine the frequency of association of bubbles with injections and inward plasma transport, as well as typical injection characteristics. Multiple geomagnetic storms and quiet periods are simulated to track and characterize inward flow behavior. Dependence on geomagnetic activity levels or drivers is also examined.

Polar ice-sheet contributions to sea level during past warm periods

NASA Astrophysics Data System (ADS)

Dutton, A.

2015-12-01

Recent sea-level rise has been dominated by thermal expansion and glacier loss, but the contribution from mass loss from the Greenland and Antarctic ice sheets is expected to exceed other contributions under future sustained warming. Due to limitations of existing ice sheet models and the lack of relevant analogues in the historical record, projecting the timing and magnitude of polar ice sheet mass loss in the future remains challenging. One approach to improving our understanding of how polar ice-sheet retreat will unfold is to integrate observations and models of sea level, ice sheets, and climate during past intervals of warmth when the polar ice sheets contributed to higher sea levels. A recent review evaluated the evidence of polar ice sheet mass loss during several warm periods, including interglacials during the mid-Pliocene warm period, Marine Isotope Stage (MIS) 11, 5e (Last Interglacial), and 1 (Holocene). Sea-level benchmarks of ice-sheet retreat during the first of these three periods, when global mean climate was ~1 to 3 deg. C warmer than preindustrial, are useful for understanding the long-term potential for future sea-level rise. Despite existing uncertainties in these reconstructions, it is clear that our present climate is warming to a level associated with significant polar ice-sheet loss in the past, resulting in a conservative estimate for a global mean sea-level rise of 6 meters above present (or more). This presentation will focus on identifying the approaches that have yielded significant advances in terms of past sea level and ice sheet reconstruction as well as outstanding challenges. A key element of recent advances in sea-level reconstructions is the ability to recognize and quantify the imprint of geophysical processes, such as glacial isostatic adjustment (GIA) and dynamic topography, that lead to significant spatial variability in sea level reconstructions. Identifying specific ice-sheet sources that contributed to higher sea levels is a challenge that is currently hindered by limited field evidence at high latitudes. Finally, I will explore the concept of how increasing the quantity and quality of paleo sea level and ice sheet reconstructions can lead to improved quantification of contemporary changes in ice sheets and sea level.

Unusual structural transition of antimicrobial VP1 peptide.

PubMed

Shanmugam, Ganesh; Phambu, Nsoki; Polavarapu, Prasad L

2011-05-01

VP1 peptide, an active domain of m-calpain enzyme with antimicrobial activity is found to undergo an unusual conformational transition in trifluoroethanol (TFE) solvent. The nature of, and time dependent variations in, circular dichroism associated with the amide I vibrations, suggest that VP1 undergoes self-aggregation forming anti-parallel β-sheet structure in TFE. Transmission electron micrograph (TEM) images revealed that β-sheet aggregates formed by VP1 possess fibril-like assemblies. Copyright © 2011 Elsevier B.V. All rights reserved.

An elastic analysis of stresses in a uniaxially loaded sheet containing an interference-fit bolt

NASA Technical Reports Server (NTRS)

Crews, J. H., Jr.

1972-01-01

The stresses in a sheet with an interference-fit bolt have been calculated for two sheet-bolt interface conditions: a frictionless interface and a fixed (no-slip) interface. The stress distributions were calculated for various combinations of sheet and bolt moduli. The results show that for repeated loading the local stress range is significantly smaller if an interference bolt is used instead of a loosely fitting one. This reduction in local stress range is more pronounced when the ratio of bolt modulus to sheet modulus is large. The analysis also indicates that currently used standard values of interference cause yielding in the sheet.

Calculations of axisymmetric vortex sheet roll-up using a panel and a filament model

NASA Technical Reports Server (NTRS)

Kantelis, J. P.; Widnall, S. E.

1986-01-01

A method for calculating the self-induced motion of a vortex sheet using discrete vortex elements is presented. Vortex panels and vortex filaments are used to simulate two-dimensional and axisymmetric vortex sheet roll-up. A straight forward application using vortex elements to simulate the motion of a disk of vorticity with an elliptic circulation distribution yields unsatisfactroy results where the vortex elements move in a chaotic manner. The difficulty is assumed to be due to the inability of a finite number of discrete vortex elements to model the singularity at the sheet edge and due to large velocity calculation errors which result from uneven sheet stretching. A model of the inner portion of the spiral is introduced to eliminate the difficulty with the sheet edge singularity. The model replaces the outermost portion of the sheet with a single vortex of equivalent circulation and a number of higher order terms which account for the asymmetry of the spiral. The resulting discrete vortex model is applied to both two-dimensional and axisymmetric sheets. The two-dimensional roll-up is compared to the solution for a semi-infinite sheet with good results.

Silicone sheet containing all-trans retinoic acid and hydroquinone for the treatment of epidermal melanosis.

PubMed

Iida, Shoko; Takushima, Akihiko; Ohura, Norihiko; Sato, Suguru; Kurita, Masakazu; Harii, Kiyonori

2013-08-01

Although bleaching treatment using all-trans retinoic acid (RA) and hydroquinone (HQ) improves epidermal melanosis, the application of two medications and the irritant dermatitis induced by RA inconvenience patients. To overcome these problems, we developed a silicone sheet containing RA and HQ. To compare the efficacy of a silicone sheet containing RA and HQ with that of conventional bleaching treatment. Silicone sheets containing 1% RA and 5% HQ were applied at night during the bleaching phase of 4 weeks, followed by application of sheets containing 5% HQ during the healing phase of 4 weeks. Hemifacial epidermal melanosis, for which the sheets were applied, was compared with a contralateral face which was treated conventionally using RA and HQ. Twenty-four Japanese women who were enrolled in this study and followed up for more than 6 months were analyzed. RA/HQ sheets improved epidermal melanosis, as did the conventional bleaching method, but irritant dermatitis occurred less in patients treated using silicone sheets. RA/HQ sheets, which are easily applied to face skin, can improve epidermal melanosis to the same extent as conventional bleaching. © 2013 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

Spiral wound extraction cartridge

DOEpatents

Wisted, E.E.; Lundquist, S.H.

1999-04-27

A cartridge device for removing an analyte from a fluid comprises a hollow core, a sheet composite comprising a particulate-loaded porous membrane and optionally at least one reinforcing spacer sheet, the particulate being capable of binding the analyte, the sheet composite being formed into a spiral configuration about the core, wherein the sheet composite is wound around itself and wherein the windings of sheet composite are of sufficient tightness so that adjacent layers are essentially free of spaces therebetween, two end caps which are disposed over the core and the lateral ends of the spirally wound sheet composite, and means for securing the end caps to the core, the end caps also being secured to the lateral ends of the spirally wound sheet composite. A method for removing an analyte from a fluid comprises the steps of providing a spirally wound element of the invention and passing the fluid containing the analyte through the element essentially normal to a surface of the sheet composite so as to bind the analyte to the particulate of the particulate-loaded porous membrane, the method optionally including the step of eluting the bound analyte from the sheet composite. 4 figs.

Structure and Dynamics of Current Sheets in 3D Magnetic Fields with the X-line

NASA Astrophysics Data System (ADS)

Frank, Anna G.; Bogdanov, S. Yu.; Bugrov, S. G.; Markov, V. S.; Dreiden, G. V.; Ostrovskaya, G. V.

2004-11-01

Experimental results are presented on the structure of current sheets formed in 3D magnetic fields with singular lines of the X-type. Two basic diagnostics were used with the device CS - 3D: two-exposure holographic interferometry and magnetic measurements. Formation of extended current sheets and plasma compression were observed in the presence of the longitudinal magnetic field component aligned with the X-line. Plasma density decreased and the sheet thickness increased with an increase of the longitudinal component. We succeeded to reveal formation of the sheets taking unusual shape, namely tilted and asymmetric sheets, in plasmas with the heavy ions. These current sheets were obviously different from the planar sheets formed in 2D magnetic fields, i.e. without longitudinal component. Analysis of typical plasma parameters made it evident that plasma dynamics and current sheet evolution should be treated on the base of the two-fluid approach. Specifically it is necessary to take into account the Hall currents in the plane perpendicular to the X-line, and the dynamic effects resulting from interaction of the Hall currents and the 3D magnetic field. Supported by RFBR, grant 03-02-17282, and ISTC, project 2098.

Laser Indirect Shock Welding of Fine Wire to Metal Sheet.

PubMed

Wang, Xiao; Huang, Tao; Luo, Yapeng; Liu, Huixia

2017-09-12

The purpose of this paper is to present an advanced method for welding fine wire to metal sheet, namely laser indirect shock welding (LISW). This process uses silica gel as driver sheet to accelerate the metal sheet toward the wire to obtain metallurgical bonding. A series of experiments were implemented to validate the welding ability of Al sheet/Cu wire and Al sheet/Ag wire. It was found that the use of a driver sheet can maintain high surface quality of the metal sheet. With the increase of laser pulse energy, the bonding area of the sheet/wire increased and the welding interfaces were nearly flat. Energy dispersive spectroscopy (EDS) results show that the intermetallic phases were absent and a short element diffusion layer which would limit the formation of the intermetallic phases emerging at the welding interface. A tensile shear test was used to measure the mechanical strength of the welding joints. The influence of laser pulse energy on the tensile failure modes was investigated, and two failure modes, including interfacial failure and failure through the wire, were observed. The nanoindentation test results indicate that as the distance to the welding interface decreased, the microhardness increased due to the plastic deformation becoming more violent.

Thermal properties of highly structured composite and aluminium sheets in an aerodynamic tunnel

NASA Astrophysics Data System (ADS)

Kulhavy, Petr; Egert, Josef

This article deals with the thermodynamic behaviour of heat shields - structured metal and composite plates. Experiments have been carried out in a wind tunnel with an additional heating, which simulates the heat source from engine or exhaust pipe and simultaneously the airflow generated during a car movement. The tested sheets with hexagonal structure were a standard commercial made of aluminium and a second manufactured by replication (lamination, diffusion) from glass fabric. The airflow in a parallel way along the sheets was analysed experimentally in order to determine the heat transfer efficiency between surfaces of sheets and surrounding airflow. The temperature on the sheets was chosen to observe the effects of different sheets material, various heat power and airflow velocity. During the experiment a thermal input below the sheets and airflow velocity through the tunnel have been changed. The thermal field distribution on the metal sheet is different than in case of composite sheet. For the composite material the thermal field distribution was more homogeneous. This article describe briefly also methods of obtaining real composite geometry based on scanned data and their reconstruction for using in some future numerical models.

Widespread Refreezing of Both Surface and Basal Melt Water Beneath the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Bell, R. E.; Tinto, K. J.; Das, I.; Wolovick, M.; Chu, W.; Creyts, T. T.; Frearson, N.

2013-12-01

The isotopically and chemically distinct, bubble-free ice observed along the Greenland Ice Sheet margin both in the Russell Glacier and north of Jacobshavn must have formed when water froze from subglacial networks. Where this refreezing occurs and what impact it has on ice sheet processes remain unclear. We use airborne radar data to demonstrate that freeze-on to the ice sheet base and associated deformation produce large ice units up to 700 m thick throughout northern Greenland. Along the ice sheet margin, in the ablation zone, surface meltwater, delivered via moulins, refreezes to the ice sheet base over rugged topography. In the interior, water melted from the ice sheet base is refrozen and surrounded by folded ice. A significant fraction of the ice sheet is modified by basal freeze-on and associated deformation. For the Eqip and Petermann catchments, representing the ice sheet margin and interior respectively, extensive airborne radar datasets show that 10%-13% of the base of the ice sheet and up to a third of the catchment width is modified by basal freeze-on. The interior units develop over relatively subdued topography with modest water flux from basal melt where conductive cooling likely dominates. Steps in the bed topography associated with subglacial valley networks may foster glaciohydraulic supercooling. The ablation zone units develop where both surface melt and crevassing are widespread and large volumes of surface meltwater will reach the base of the ice sheet. The relatively steep topography at the upslope edge of the ablation zone units combined with the larger water flux suggests that supercooling plays a greater role in their formation. The ice qualities of the ablation zone units should reflect the relatively fresh surface melt whereas the chemistry of the interior units should reflect solute-rich basal melt. Changes in basal conditions such as the presence of till patches may contribute to the formation of the large basal units near the Northeast Ice Stream. The contrasting rheology of glacial and interglacial ice may also enhance the deformation associated with freeze-on beneath large ice sheets. The occurrence of basal units both in the ice sheet interior and in the thermally very different ablation zone indicates refreezing is widespread and can occur in many environments beneath an ice sheet. This process appears to influence the morphology and behavior of the ice sheet from top to bottom.

Reconstructing the last Irish Ice Sheet 2: a geomorphologically-driven model of ice sheet growth, retreat and dynamics

NASA Astrophysics Data System (ADS)

Greenwood, Sarah L.; Clark, Chris D.

2009-12-01

The ice sheet that once covered Ireland has a long history of investigation. Much prior work focussed on localised evidence-based reconstructions and ice-marginal dynamics and chronologies, with less attention paid to an ice sheet wide view of the first order properties of the ice sheet: centres of mass, ice divide structure, ice flow geometry and behaviour and changes thereof. In this paper we focus on the latter aspect and use our new, countrywide glacial geomorphological mapping of the Irish landscape (>39 000 landforms), and our analysis of the palaeo-glaciological significance of observed landform assemblages (article Part 1), to build an ice sheet reconstruction yielding these fundamental ice sheet properties. We present a seven stage model of ice sheet evolution, from initiation to demise, in the form of palaeo-geographic maps. An early incursion of ice from Scotland likely coalesced with local ice caps and spread in a south-westerly direction 200 km across Ireland. A semi-independent Irish Ice Sheet was then established during ice sheet growth, with a branching ice divide structure whose main axis migrated up to 140 km from the west coast towards the east. Ice stream systems converging on Donegal Bay in the west and funnelling through the North Channel and Irish Sea Basin in the east emerge as major flow components of the maximum stages of glaciation. Ice cover is reconstructed as extending to the continental shelf break. The Irish Ice Sheet became autonomous (i.e. separate from the British Ice Sheet) during deglaciation and fragmented into multiple ice masses, each decaying towards the west. Final sites of demise were likely over the mountains of Donegal, Leitrim and Connemara. Patterns of growth and decay of the ice sheet are shown to be radically different: asynchronous and asymmetric in both spatial and temporal domains. We implicate collapse of the ice stream system in the North Channel - Irish Sea Basin in driving such asymmetry, since rapid collapse would sever the ties between the British and Irish Ice Sheets and drive flow configuration changes in response. Enhanced calving and flow acceleration in response to rising relative sea level is speculated to have undermined the integrity of the ice stream system, precipitating its collapse and driving the reconstructed pattern of ice sheet evolution.

Construction of osteochondral-like tissue graft combining β-tricalcium phosphate block and scaffold-free centrifuged chondrocyte cell sheet.

PubMed

Niyama, Kouhei; Ide, Naoto; Onoue, Kaori; Okabe, Takahiro; Wakitani, Shigeyuki; Takagi, Mutsumi

2011-09-01

The combination of a β-tricalcium phosphate (βTCP) block with a scaffold-free chondrocyte sheet formed by the centrifugation of chondrocytes in a well was investigated with the aim of constructing an osteochondral-like structure. Human and porcine articular cartilage chondrocytes were respectively centrifuged in a 96-well plate or cell culture insert (0.32 cm(2)) that was set in a 24-well plate, cultivated in the respective vessel for 3 weeks, and the cell sheets were harvested. In some cases, a cylindrical βTCP block (diameter 5 mm, height 3 mm) was placed on the sheet on days 1-7. The sheet size, cell number, and sulfated glycosaminoglycan accumulation were determined. The use of a 96-well plate for not suspension but adhesion culture and the initial centrifugation of a well containing cells were crucial to obtaining a uniformly thick cell sheet. The glycosaminoglycan density of the harvested cell sheet was comparable to that of the pellet culture. An inoculum cell number of more than 31 × 10(5) cells tended to result in a curved cell sheet. Culture involving 18.6 × 10(5) cells and the 96-well plate for adhesion culture showed no curving of the cell sheet (thickness of 0.85 mm), and these were found to be the best of the culture conditions tested. The timing of the addition of a βTCP block to the cell sheet (1-7 days) markedly affected the balance between the thickness of cell sheet parts on and in the βTCP block. Centrifugation and subsequent cultivation of chondrocytes (18.6 × 10(5) cells) in a 96-well plate for adhesion culture led to the production of a scaffold-free cartilage-like cell sheet with a thickness of 0.85 mm. A combined osteochondral-like structure was produced by putting a βTCP block on the cell sheet. The thickness of the cell sheet on the βTCP block and the binding strength between the cell sheet and the βTCP block could be optimized by adjusting the inoculum cell number and timing of βTCP block addition.

Multipotent mesenchymal stromal cell sheet therapy for bisphosphonate-related osteonecrosis of the jaw in a rat model.

PubMed

Kaibuchi, Nobuyuki; Iwata, Takanori; Yamato, Masayuki; Okano, Teruo; Ando, Tomohiro

2016-09-15

Bisphosphonates (BPs) inhibit bone resorption and are frequently used to treat osteoporosis, bone metastasis, and other conditions that result in bone fragility. However, numerous studies have reported that BPs are closely related to the development of osteonecrosis of the jaw (BRONJ), which is an intractable disease. Recent studies have demonstrated that intravenous infusion of multipotent mesenchymal stromal cells (MSCs) is effective for the treatment of BRONJ-like disease models. However, the stability of injected MSCs is relatively low. In this study, the protein level of vascular endothelial growth factor in BP-treated MSCs was significantly lower than untreated-MSCs. The mRNA expression levels of receptor activator of nuclear factor κ-B ligand and osteoprotegerin were significantly decreased in BP-treated MSCs. We developed a tissue-engineered cell sheet of allogeneic enhanced green fluorescent protein (EGFP)-labeled MSCs and investigated the effect of MSC sheet transplantation in a BRONJ-like rat model. The MSC sheet group showed wound healing in most cases compared with the control group and MSC intravenous injection group (occurrence of bone exposure: 12.5% compared with 80% and 100%, respectively). Immunofluorescence staining revealed that EGFP-positive cells were localized around newly formed blood vessels in the transplanted sub-mucosa at 2weeks after transplantation. Blood vessels were significantly observed in the MSC sheet group compared to in the control group and MSC intravenous injection group (106±9.6 compared with 40±5.3 and 62±10.2 vessels/mm(2), respectively). These results suggest that allogeneic MSC sheet transplantation is a promising alternative approach for treating BRONJ. Bisphosphonates are frequently used to treat osteoporosis, bone metastasis of various cancers, and other diseases. However, bisphosphonate related-osteonecrosis of the jaw (BRONJ) is an intractable disease because it often recurs after surgery or is exacerbated following conservative treatment. Therefore, an alternative approach for treating BRONJ is needed. In this study, we developed a bone marrow-derived multipotent mesenchymal stromal cell (MSC) sheet to treat BRONJ and investigated the effect of MSC sheet transplantation in a rat model of BRONJ-like disease. The MSC sheet transplantation group showed wound healing in most cases, while only minimal healing was observed in the control group and MSC intravenous injection group. Our results suggest that the MSC sheet is a promising alternative approach for the treatment of BRONJ. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Rainfall and sheet power equation for interrill erosion on steep hillslope

USDA-ARS?s Scientific Manuscript database

Splash and sheet erosion processes dominate on most undisturbed hillslopes of rangeland. Interrill soil erosion should consider the influence of both raindrop and sheet flow to work of soil particles detached by raindrop impact and transported by rainfall-disturbed sheet flow. Interrill erosion equa...

47 CFR 32.3999 - Instructions for balance sheet accounts-liabilities and stockholders' equity.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Instructions for balance sheet accounts-liabilities and stockholders' equity. 32.3999 Section 32.3999 Telecommunication FEDERAL COMMUNICATIONS... Instructions for Balance Sheet Accounts § 32.3999 Instructions for balance sheet accounts—liabilities and...

47 CFR 32.3999 - Instructions for balance sheet accounts-liabilities and stockholders' equity.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Instructions for balance sheet accounts-liabilities and stockholders' equity. 32.3999 Section 32.3999 Telecommunication FEDERAL COMMUNICATIONS... Instructions for Balance Sheet Accounts § 32.3999 Instructions for balance sheet accounts—liabilities and...

Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions

PubMed Central

Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

2016-01-01

Clinical trials have been performed using autologous tissue-engineered epithelial cell sheets for corneal regenerative medicine. To improve stem cell-based therapy for convenient clinical practice, new techniques are required for preserving reconstructed tissues and their stem/progenitor cells until they are ready for use. In the present study, we screened potential preservative agents and developed a novel medium for preserving the cell sheets and their stem/progenitor cells; the effects were evaluated with a luciferase-based viability assay. Nrf2 activators, specifically ebselen, could maintain high ATP levels during preservation. Ebselen also showed a strong influence on maintenance of the viability, morphology, and stem cell function of the cell sheets preserved under hypothermia by protecting them from reactive oxygen species-induced damage. Furthermore, ebselen drastically improved the preservation performance of human cornea tissues and their stem cells. Therefore, ebselen shows good potential as a useful preservation agent in regenerative medicine as well as in cornea transplantation. PMID:27966584

Epithelial sheet folding induces lumen formation by Madin-Darby canine kidney cells in a collagen gel.

PubMed

Ishida, Sumire; Tanaka, Ryosuke; Yamaguchi, Naoya; Ogata, Genki; Mizutani, Takeomi; Kawabata, Kazushige; Haga, Hisashi

2014-01-01

Lumen formation is important for morphogenesis; however, an unanswered question is whether it involves the collective migration of epithelial cells. Here, using a collagen gel overlay culture method, we show that Madin-Darby canine kidney cells migrated collectively and formed a luminal structure in a collagen gel. Immediately after the collagen gel overlay, an epithelial sheet folded from the periphery, migrated inwardly, and formed a luminal structure. The inhibition of integrin-β1 or Rac1 activity decreased the migration rate of the peripheral cells after the sheets folded. Moreover, lumen formation was perturbed by disruption of apical-basolateral polarity induced by transforming growth factor-β1. These results indicate that cell migration and cell polarity play an important role in folding. To further explore epithelial sheet folding, we developed a computer-simulated mechanical model based on the rigidity of the extracellular matrix. It indicated a soft substrate is required for the folding movement.

Photophysiology and albedo-changing potential of the ice algal community on the surface of the Greenland ice sheet

PubMed Central

Yallop, Marian L; Anesio, Alexandre M; Perkins, Rupert G; Cook, Joseph; Telling, Jon; Fagan, Daniel; MacFarlane, James; Stibal, Marek; Barker, Gary; Bellas, Chris; Hodson, Andy; Tranter, Martyn; Wadham, Jemma; Roberts, Nicholas W

2012-01-01

Darkening of parts of the Greenland ice sheet surface during the summer months leads to reduced albedo and increased melting. Here we show that heavily pigmented, actively photosynthesising microalgae and cyanobacteria are present on the bare ice. We demonstrate the widespread abundance of green algae in the Zygnematophyceae on the ice sheet surface in Southwest Greenland. Photophysiological measurements (variable chlorophyll fluorescence) indicate that the ice algae likely use screening mechanisms to downregulate photosynthesis when exposed to high intensities of visible and ultraviolet radiation, rather than non-photochemical quenching or cell movement. Using imaging microspectrophotometry, we demonstrate that intact cells and filaments absorb light with characteristic spectral profiles across ultraviolet and visible wavelengths, whereas inorganic dust particles typical for these areas display little absorption. Our results indicate that the phototrophic community growing directly on the bare ice, through their photophysiology, most likely have an important role in changing albedo, and subsequently may impact melt rates on the ice sheet. PMID:23018772

Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions.

PubMed

Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

2016-12-14

Clinical trials have been performed using autologous tissue-engineered epithelial cell sheets for corneal regenerative medicine. To improve stem cell-based therapy for convenient clinical practice, new techniques are required for preserving reconstructed tissues and their stem/progenitor cells until they are ready for use. In the present study, we screened potential preservative agents and developed a novel medium for preserving the cell sheets and their stem/progenitor cells; the effects were evaluated with a luciferase-based viability assay. Nrf2 activators, specifically ebselen, could maintain high ATP levels during preservation. Ebselen also showed a strong influence on maintenance of the viability, morphology, and stem cell function of the cell sheets preserved under hypothermia by protecting them from reactive oxygen species-induced damage. Furthermore, ebselen drastically improved the preservation performance of human cornea tissues and their stem cells. Therefore, ebselen shows good potential as a useful preservation agent in regenerative medicine as well as in cornea transplantation.

Multiple-satellite studies of magnetospheric substorms: Plasma sheet recovery and the poleward leap of auroral-zone activity

NASA Technical Reports Server (NTRS)

Pytte, T.; Mcpherron, R. L.; Kivelson, M. G.; West, H. I., Jr.; Hones, E. W., Jr.

1977-01-01

Particle observations from pairs of satellites (Ogo 5, Vela 4A and 5B, Imp 3) during the recovery of plasma sheet thickness late in substorms were examined. Six of the nine events occurred within about 5 min in locations near the estimated position of the neutral sheet, but over wide ranges of east-west and radial separations. The time of occurrence and spatial extent of the recovery were related to the onset (defined by ground Pi 2 pulsations) and approximate location (estimated from ground mid-latitude magnetic signatures) of substorm expansions. It was found that the plasma sheet recovery occurred 10 - 30 min after the last in a series of Pi bursts, which were interpreted to indicate that the recovery was not due directly to a late, high latitude substorm expansion. The recovery was also observed to occur after the substorm current wedge had moved into the evening sector and to extend far to the east of the center of the last preceding substorm expansion.

Post‐Graphene 2D Chemistry: The Emerging Field of Molybdenum Disulfide and Black Phosphorus Functionalization

PubMed Central

Hauke, Frank

2018-01-01

Abstract The current state of the chemical functionalization of three types of single sheet 2D materials, namely, graphene, molybdenum disulfide (MoS2), and black phosphorus (BP) is summarized. Such 2D sheet polymers are currently an emerging field at the interface of synthetic chemistry, physics, and materials science. Both covalent and non‐covalent functionalization of sheet architectures allows a systematic modification of their properties, that is, an improvement of solubility and processability, the prevention of re‐aggregation, or band‐gap tuning. Next to successful functionalization concepts, fundamental challenges are also addressed. These include the insolubility and polydispersity of most 2D sheet polymers, the development of suitable characterization tools, the identification of effective binding strategies, the chemical activation of the usually rather unreactive basal planes for covalent addend binding, and the regioselectivity of plane addition reactions. Although a number of these questions remain elusive in this Review, the first promising concepts to overcome such hurdles are presented. PMID:29024321

Photophysiology and albedo-changing potential of the ice algal community on the surface of the Greenland ice sheet.

PubMed

Yallop, Marian L; Anesio, Alexandre M; Perkins, Rupert G; Cook, Joseph; Telling, Jon; Fagan, Daniel; MacFarlane, James; Stibal, Marek; Barker, Gary; Bellas, Chris; Hodson, Andy; Tranter, Martyn; Wadham, Jemma; Roberts, Nicholas W

2012-12-01

Darkening of parts of the Greenland ice sheet surface during the summer months leads to reduced albedo and increased melting. Here we show that heavily pigmented, actively photosynthesising microalgae and cyanobacteria are present on the bare ice. We demonstrate the widespread abundance of green algae in the Zygnematophyceae on the ice sheet surface in Southwest Greenland. Photophysiological measurements (variable chlorophyll fluorescence) indicate that the ice algae likely use screening mechanisms to downregulate photosynthesis when exposed to high intensities of visible and ultraviolet radiation, rather than non-photochemical quenching or cell movement. Using imaging microspectrophotometry, we demonstrate that intact cells and filaments absorb light with characteristic spectral profiles across ultraviolet and visible wavelengths, whereas inorganic dust particles typical for these areas display little absorption. Our results indicate that the phototrophic community growing directly on the bare ice, through their photophysiology, most likely have an important role in changing albedo, and subsequently may impact melt rates on the ice sheet.

Ice sheets as a significant source of highly reactive nanoparticulate iron to the oceans.

PubMed

Hawkings, Jon R; Wadham, Jemma L; Tranter, Martyn; Raiswell, Rob; Benning, Liane G; Statham, Peter J; Tedstone, Andrew; Nienow, Peter; Lee, Katherine; Telling, Jon

2014-05-21

The Greenland and Antarctic Ice Sheets cover ~ 10% of global land surface, but are rarely considered as active components of the global iron cycle. The ocean waters around both ice sheets harbour highly productive coastal ecosystems, many of which are iron limited. Measurements of iron concentrations in subglacial runoff from a large Greenland Ice Sheet catchment reveal the potential for globally significant export of labile iron fractions to the near-coastal euphotic zone. We estimate that the flux of bioavailable iron associated with glacial runoff is 0.40-2.54 Tg per year in Greenland and 0.06-0.17 Tg per year in Antarctica. Iron fluxes are dominated by a highly reactive and potentially bioavailable nanoparticulate suspended sediment fraction, similar to that identified in Antarctic icebergs. Estimates of labile iron fluxes in meltwater are comparable with aeolian dust fluxes to the oceans surrounding Greenland and Antarctica, and are similarly expected to increase in a warming climate with enhanced melting.

From Tragedy to Triumph - Rebuilding Green Homes after Disaster (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2009-04-01

Energy Efficiency/Renewable Energy Fact Sheets, No. 1. Series to include practical, useful info to help people change their behavior around energy usage and "greenness". Greensburg is hanging its future on sustainable development; these fact sheet sheets should help citizens understand what they can do to be a part of that focus. Fact Sheets cover: saving energy and water, using renewable energy (particular interest in small wind), driving "green", general sustainability, living green.

Residual stress measurement in silicon sheet by shadow moire interferometry

NASA Technical Reports Server (NTRS)

Kwon, Y.; Danyluk, S.; Bucciarelli, L.; Kalejs, J. P.

1987-01-01

A shadow moire interferometry technique has been developed to measure residual strain in thin silicon sheet. The curvature of a segment of sheet undergoing four-point bending is analyzed to include the applied bending moments, the in-plane residual stresses, and the 'end effect' of the sheet since it is of finite length. The technique is applied to obtain residual stress distributions for silicon sheet grown by the edge-defined film-fed growth technique.

Hypsometric amplification and routing moderation of Greenland ice sheet meltwater release

NASA Astrophysics Data System (ADS)

van As, Dirk; Mikkelsen, Andreas Bech; Holtegaard Nielsen, Morten; Box, Jason E.; Claesson Liljedahl, Lillemor; Lindbäck, Katrin; Pitcher, Lincoln; Hasholt, Bent

2017-06-01

Concurrent ice sheet surface runoff and proglacial discharge monitoring are essential for understanding Greenland ice sheet meltwater release. We use an updated, well-constrained river discharge time series from the Watson River in southwest Greenland, with an accurate, observation-based ice sheet surface mass balance model of the ˜ 12 000 km2 ice sheet area feeding the river. For the 2006-2015 decade, we find a large range of a factor of 3 in interannual variability in discharge. The amount of discharge is amplified ˜ 56 % by the ice sheet's hypsometry, i.e., area increase with elevation. A good match between river discharge and ice sheet surface meltwater production is found after introducing elevation-dependent transit delays that moderate diurnal variability in meltwater release by a factor of 10-20. The routing lag time increases with ice sheet elevation and attains values in excess of 1 week for the upper reaches of the runoff area at ˜ 1800 m above sea level. These multi-day routing delays ensure that the highest proglacial discharge levels and thus overbank flooding events are more likely to occur after multi-day melt episodes. Finally, for the Watson River ice sheet catchment, we find no evidence of meltwater storage in or release from the en- and subglacial environments in quantities exceeding our methodological uncertainty, based on the good match between ice sheet runoff and proglacial discharge.

A comprehensive study of the electrically conducting water based CuO and Al2O3 nanoparticles over coupled nanofluid-sheet interface

NASA Astrophysics Data System (ADS)

Ahmad, R.

2016-02-01

Many studies on nanofluid flow over a permeable/impermeable sheet prescribe the kinematics of the sheet and disregard the sheet’s mechanics. However, the current study is one of the infrequent contributions that anticipate the mechanics of both the electrically conducting nanofluid (a homogeneous mixture of nanoparticles and base fluid) and the sheet. Two types of nanoparticles, alumina and copper, with water as a base fluid over the sheet are considered. With the help of the similarity transformations, the corresponding partial differential equations for the coupled nanofluid-sheet interface are transformed into a system of ordinary differential equations. The simulations are done by using the experimentally verified results from the previous studies for viscosity and thermal conductivity. Self-similar solutions are attained by considering both analytical and numerical techniques. Dual skin friction coefficients are attained with different copper and alumina nanoparticles over both the stretching and viscous sheets. The influence of the Eckert number, magnetic and mass suction/blowing parameters on the dimensionless velocity, temperature, skin friction and heat transfer rates over the nanofluid-sheet interface are presented graphically as well as numerically. The obtained results are of potential benefit for studying nanofluid flow over various soft surfaces such as synthetic plastics, soft silicone sheet and soft synthetic rubber sheet. These surfaces are easily deformed by thermal fluctuations.

A flexible tactile sensitive sheet using a hetero-core fiber optic sensor

NASA Astrophysics Data System (ADS)

Fujino, S.; Yamazaki, H.; Hosoki, A.; Watanabe, K.

2014-05-01

In this report, we have designed a tactile sensitive sheet based on a hetero-core fiber-optic sensor, which realize an areal sensing by using single sensor potion in one optical fiber line. Recently, flexible and wide-area tactile sensing technology is expected to applied to acquired biological information in living space and robot achieve long-term care services such as welfare and nursing-care and humanoid technology. A hetero-core fiber-optic sensor has several advantages such as thin and flexible transmission line, immunity to EMI. Additionally this sensor is sensitive to moderate bending actions with optical loss changes and is independent of temperature fluctuation. Thus, the hetero-core fiber-optic sensor can be suitable for areal tactile sensing. We measure pressure characteristic of the proposed sensitive sheet by changing the pressure position and pinching characteristic on the surface. The proposed tactile sensitive sheet shows monotonic responses on the whole sensitive sheet surface although different sensitivity by the position is observed at the sensitive sheet surface. Moreover, the tactile sensitive sheet could sufficiently detect the pinching motion. In addition, in order to realize the discrimination between pressure and pinch, we fabricated a doubled-over sensor using a set of tactile sensitive sheets, which has different kinds of silicon robbers as a sensitive sheet surface. In conclusion, the flexible material could be given to the tactile sensation which is attached under proposed sensitive sheet.

Preforming of polydioxanone sheets for orbital wall fractures - A technical note.

PubMed

Kruber, Daniel; Hierl, Thomas; Doerfler, Hans-Martin; Huempfner-Hierl, Heike; Krause, Matthias

2018-07-01

Polydioxanone (PDS) sheets are commonly used in the treatment of orbital wall fractures. A potential drawback of PDS is that it may be difficult to adapt to the anatomy of the orbital walls. Therefore a study was conceived to test the feasibility of preforming PDS sheets. PDS sheet material was water-heated and preformed using a template based on a statistical anatomical model. Then the deformed sheet was cooled, stored and compared to the original model to investigate post-deformation changes. PDS sheet material could easily be deformed using a mould. No significant post-cooling shape changes were noticed. PDS sheet material can be preformed into complex geometric shapes. This could be a benefit in the treatment of orbital wall fractures. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Osteoblastic mesenchymal stem cell sheet combined with Choukroun platelet-rich fibrin induces bone formation at an ectopic site.

PubMed

Wang, Zhifa; Weng, Yanming; Lu, Shengjun; Zong, Chunlin; Qiu, Jianyong; Liu, Yanpu; Liu, Bin

2015-08-01

To analyze the effects of platelet-rich fibrin (PRF) on mesenchymal stem cells (MSCs) in vitro and investigate in vivo bone formation by MSC sheets with PRF. Cell proliferation and expression of osteogenesis-related genes within MSC sheets were assessed upon exposure to PRF from the same donors. We then injected MSC sheet fragments with or without PRF subcutaneously in nude mice and assessed bone formation by micro-computed tomography and histological analyses. PRF significantly stimulated MSC proliferation and osteogenesis in vitro. MSC sheets injected with or without PRF formed new bone, but those with PRF produced significantly more and denser bone. MSC sheets can be used to generate tissue engineered bone upon injection, and PRF increases the osteogenic capacity of MSC sheets in vitro and in vivo. © 2014 Wiley Periodicals, Inc.

Scanning light-sheet microscopy in the whole mouse brain with HiLo background rejection.

PubMed

Mertz, Jerome; Kim, Jinhyun

2010-01-01

It is well known that light-sheet illumination can enable optically sectioned wide-field imaging of macroscopic samples. However, the optical sectioning capacity of a light-sheet macroscope is undermined by sample-induced scattering or aberrations that broaden the thickness of the sheet illumination. We present a technique to enhance the optical sectioning capacity of a scanning light-sheet microscope by out-of-focus background rejection. The technique, called HiLo microscopy, makes use of two images sequentially acquired with uniform and structured sheet illumination. An optically sectioned image is then synthesized by fusing high and low spatial frequency information from both images. The benefits of combining light-sheet macroscopy and HiLo background rejection are demonstrated in optically cleared whole mouse brain samples, using both green fluorescent protein (GFP)-fluorescence and dark-field scattered light contrast.

Scanning light-sheet microscopy in the whole mouse brain with HiLo background rejection

NASA Astrophysics Data System (ADS)

Mertz, Jerome; Kim, Jinhyun

2010-01-01

It is well known that light-sheet illumination can enable optically sectioned wide-field imaging of macroscopic samples. However, the optical sectioning capacity of a light-sheet macroscope is undermined by sample-induced scattering or aberrations that broaden the thickness of the sheet illumination. We present a technique to enhance the optical sectioning capacity of a scanning light-sheet microscope by out-of-focus background rejection. The technique, called HiLo microscopy, makes use of two images sequentially acquired with uniform and structured sheet illumination. An optically sectioned image is then synthesized by fusing high and low spatial frequency information from both images. The benefits of combining light-sheet macroscopy and HiLo background rejection are demonstrated in optically cleared whole mouse brain samples, using both green fluorescent protein (GFP)-fluorescence and dark-field scattered light contrast.

Experimental analysis of Nd-YAG laser cutting of sheet materials - A review

NASA Astrophysics Data System (ADS)

Sharma, Amit; Yadava, Vinod

2018-01-01

Cutting of sheet material is considered as an important process due to its relevance among products of everyday life such as aircrafts, ships, cars, furniture etc. Among various sheet cutting processes (ASCPs), laser beam cutting is one of the most capable ASCP to create complex geometries with stringent design requirements in difficult-to-cut sheet materials. Based on the recent research work in the area of sheet cutting, it is found that the Nd-YAG laser is used for cutting of sheet material in general and reflective sheet material in particular. This paper reviews the experimental analysis of Nd-YAG laser cutting process, carried out to study the influence of laser cutting parameters on the process performance index. The significance of experimental modeling and different optimization approaches employed by various researchers has also been discussed in this study.

Development of anti-adhesive spongy sheet composed of hyaluronic acid and collagen containing epidermal growth factor.

PubMed

Kuroyanagi, Misato; Yamamoto, Akiko; Shimizu, Nahoko; Toi, Ayako; Inomata, Tomonori; Takeda, Akira; Kuroyanagi, Yoshimitsu

2014-01-01

Anti-adhesive products need to be designed while considering the concept of wound healing. Two main events must proceed simultaneously: facilitating wound healing in surgically excised tissue, as well as preventing injured tissue from adhering to the surrounding tissue. The present study aimed to develop an anti-adhesive spongy sheet composed of hyaluronic acid and collagen (Col) containing epidermal growth factor, and to investigate the potential of this spongy sheet using an in vitro wound surface model (placing a spongy sheet on a fibroblast-incorporating Col gel sheet) and an in vitro inter-tissue model (placing a spongy sheet between two fibroblast-incorporating Col gel sheets). These in vitro experiments demonstrated that this spongy sheet effectively stimulates fibroblasts to release an increased amount of vascular endothelial growth factor and hepatocyte growth factor, which are essential for wound healing to proceed succesfully. In addition, anti-adhesive performance of this spongy sheet was evaluated in animal experiments using Sprague Dawley rats. Under anesthesia, a 1 cm × 2 cm segment of peritoneum was superficially excised from walls, and the cecum was then abraded by scraping with a scalpel blade over a 1 cm × 2 cm area. A piece of spongy sheet was placed on the peritoneal defect. Both defects were placed in contact, and the incision was closed by suturing. Peritoneal condition was evaluated after one week. This spongy sheet was capable of facilitating the wound healing of surgically excised tissue and preventing surgically excised tissue from adhering to surrounding tissues.

Electro-thermo-mechanical coupling analysis of deep drawing with resistance heating for aluminum matrix composites sheet

NASA Astrophysics Data System (ADS)

Zhang, Kaifeng; Zhang, Tuoda; Wang, Bo

2013-05-01

Recently, electro-plastic forming to be a focus of attention in materials hot processing research area, because it is a sort of energy-saving, high efficient and green manufacturing technology. An electro-thermo-mechanical model can be adopted to carry out the sequence simulation of aluminum matrix composites sheet deep drawing via electro-thermal coupling and thermal-mechanical coupling method. The first step of process is resistance heating of sheet, then turn off the power, and the second step is deep drawing. Temperature distribution of SiCp/2024Al composite sheet by resistance heating and sheet deep drawing deformation were analyzed. During the simulation, effect of contact resistances, temperature coefficient of resistance for electrode material and SiCp/2024Al composite on temperature distribution were integrally considered. The simulation results demonstrate that Sicp/2024Al composite sheet can be rapidly heated to 400° in 30s using resistances heating and the sheet temperature can be controlled by adjusting the current density. Physical properties of the electrode materials can significantly affect the composite sheet temperature distribution. The temperature difference between the center and the side of the sheet is proportional to the thermal conductivity of the electrode, the principal cause of which is that the heat transfers from the sheet to the electrode. SiCp/2024Al thin-wall part can be intactly manufactured at strain rate of 0.08s-1 and the sheet thickness thinning rate is limited within 20%, which corresponds well to the experimental result.

Potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets

NASA Astrophysics Data System (ADS)

Livingstone, S. J.; Clark, C. D.; Woodward, J.; Kingslake, J.

2013-11-01

We use the Shreve hydraulic potential equation as a simplified approach to investigate potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets. We validate the method by demonstrating its ability to recall the locations of >60% of the known subglacial lakes beneath the Antarctic Ice Sheet. This is despite uncertainty in the ice-sheet bed elevation and our simplified modelling approach. However, we predict many more lakes than are observed. Hence we suggest that thousands of subglacial lakes remain to be found. Applying our technique to the Greenland Ice Sheet, where very few subglacial lakes have so far been observed, recalls 1607 potential lake locations, covering 1.2% of the bed. Our results will therefore provide suitable targets for geophysical surveys aimed at identifying lakes beneath Greenland. We also apply the technique to modelled past ice-sheet configurations and find that during deglaciation both ice sheets likely had more subglacial lakes at their beds. These lakes, inherited from past ice-sheet configurations, would not form under current surface conditions, but are able to persist, suggesting a retreating ice-sheet will have many more subglacial lakes than advancing ones. We also investigate subglacial drainage pathways of the present-day and former Greenland and Antarctic ice sheets. Key sectors of the ice sheets, such as the Siple Coast (Antarctica) and NE Greenland Ice Stream system, are suggested to have been susceptible to subglacial drainage switching. We discuss how our results impact our understanding of meltwater drainage, basal lubrication and ice-stream formation.

A statistical study on the shape and position of the magnetotail neutral sheet

NASA Astrophysics Data System (ADS)

Xiao, Sudong; Zhang, Tielong; Ge, Yasong; Wang, Guoqiang; Baumjohann, Wolfgang; Nakamura, Rumi

2016-02-01

We study the average shape and position of the magnetotail neutral sheet based on magnetic field data obtained by Cluster, Geotail, TC-1, and THEMIS from the years 1995 to 2013. All data in the aberrated GSM (geocentric solar magnetospheric) coordinate system are normalized to the same solar wind pressure 2 nPa and downtail distance X ˜ -20RE. Our results show characteristics of the neutral sheet, as follows. (1) The neutral sheet assumes a greater degree of curve in the YZ cross section when the dipole tilt increases, the Earth dipole tilt angle affects the neutral sheet configuration not only in the YZ cross section but also in the XY cross section, and the neutral sheet assumes a more significant degree of tilt in the XY cross section when the dipole tilt increases. (2) Counterclockwise twisting of the neutral sheet with 3.10° is observed, looking along the downtail direction, for the positive interplanetary magnetic field (IMF) BY with a value of 3 to 8 nT, and clockwise twisting of the neutral sheet with 3.37° for the negative IMF BY with a value of -8 to -3 nT, and a northward IMF can result in a greater twisting of the near-tail neutral sheet than southward. The above results can be a reference to the neutral sheet model. Our large database also shows that the displaced ellipse model is effective to study the average shape of the neutral sheet with proper parameters when the dipole tilt angle is larger (less) than 10° (-10° ).

Glaciological constraints on current ice mass changes from modelling the ice sheets over the glacial cycles

NASA Astrophysics Data System (ADS)

Huybrechts, P.

2003-04-01

The evolution of continental ice sheets introduces a long time scale in the climate system. Large ice sheets have a memory of millenia, hence the present-day ice sheets of Greenland and Antarctica are still adjusting to climatic variations extending back to the last glacial period. This trend is separate from the direct response to mass-balance changes on decadal time scales and needs to be correctly accounted for when assessing current and future contributions to sea level. One way to obtain estimates of current ice mass changes is to model the past history of the ice sheets and their underlying beds over the glacial cycles. Such calculations assist to distinguish between the longer-term ice-dynamic evolution and short-term mass-balance changes when interpreting altimetry data, and are helpful to isolate the effects of postglacial rebound from gravity and altimetry trends. The presentation will discuss results obtained from 3-D thermomechanical ice-sheet/lithosphere/bedrock models applied to the Antarctic and Greenland ice sheets. The simulations are forced by time-dependent boundary conditions derived from sediment and ice core records and are constrained by geomorphological and glacial-geological data of past ice sheet and sea-level stands. Current simulations suggest that the Greenland ice sheet is close to balance, while the Antarctic ice sheet is still losing mass, mainly due to incomplete grounding-line retreat of the West Antarctic ice sheet since the LGM. The results indicate that altimetry trends are likely dominated by ice thickness changes but that the gravitational signal mainly reflects postglacial rebound.

A novel closed cell culture device for fabrication of corneal epithelial cell sheets.

PubMed

Nakajima, Ryota; Kobayashi, Toyoshige; Moriya, Noboru; Mizutani, Manabu; Kan, Kazutoshi; Nozaki, Takayuki; Saitoh, Kazuo; Yamato, Masayuki; Okano, Teruo; Takeda, Shizu

2015-11-01

Automation technology for cell sheet-based tissue engineering would need to optimize the cell sheet fabrication process, stabilize cell sheet quality and reduce biological contamination risks. Biological contamination must be avoided in clinical settings. A closed culture system provides a solution for this. In the present study, we developed a closed culture device called a cell cartridge, to be used in a closed cell culture system for fabricating corneal epithelial cell sheets. Rabbit limbal epithelial cells were cultured on the surface of a porous membrane with 3T3 feeder cells, which are separate from the epithelial cells in the cell cartridges and in the cell-culture inserts as a control. To fabricate the stratified cell sheets, five different thicknesses of the membranes which were welded to the cell cartridge, were examined. Multilayered corneal epithelial cell sheets were fabricated in cell cartridges that were welded to a 25 µm-thick gas-permeable membrane, which was similar to the results with the cell-culture inserts. However, stratification of corneal epithelial cell sheets did not occur with cell cartridges that were welded to 100-300 µm-thick gas-permeable membranes. The fabricated cell sheets were evaluated by histological analyses to examine the expression of corneal epithelial-specific markers. Immunohistochemical analyses showed that a putative stem cell marker, p63, a corneal epithelial differentiation maker, CK3, and a barrier function marker, Claudin-1, were expressed in the appropriate position in the cell sheets. These results suggest that the cell cartridge is effective for fabricating corneal epithelial cell sheets. Copyright © 2012 John Wiley & Sons, Ltd.

24 CFR 1710.117 - Cost sheet, signature of Senior Executive Officer.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Cost sheet, signature of Senior... REGISTRATION Reporting Requirements § 1710.117 Cost sheet, signature of Senior Executive Officer. (a) Cost... description of our subdivision and development plans. Signature of Senior Executive Officer (2) Cost sheet...

46 CFR 160.005-1 - Incorporation by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

... makes reference to the following documents: (1) Federal Specification: L-P-375C—Plastic Film, Flexible....005-1: (Sheet 1) Cutting Pattern and General Arrangement (Adult). (Sheet 2) Alternate Stitching of Tapes and Webbing (Adult and Child). (Sheet 3) Pad Detail (Adult). (Sheet 4) Cutting Pattern and General...

46 CFR 160.005-1 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... makes reference to the following documents: (1) Federal Specification: L-P-375C—Plastic Film, Flexible....005-1: (Sheet 1) Cutting Pattern and General Arrangement (Adult). (Sheet 2) Alternate Stitching of Tapes and Webbing (Adult and Child). (Sheet 3) Pad Detail (Adult). (Sheet 4) Cutting Pattern and General...

46 CFR 160.005-1 - Incorporation by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... makes reference to the following documents: (1) Federal Specification: L-P-375C—Plastic Film, Flexible....005-1: (Sheet 1) Cutting Pattern and General Arrangement (Adult). (Sheet 2) Alternate Stitching of Tapes and Webbing (Adult and Child). (Sheet 3) Pad Detail (Adult). (Sheet 4) Cutting Pattern and General...

46 CFR 160.005-1 - Incorporation by reference.

Code of Federal Regulations, 2011 CFR

2011-10-01

... makes reference to the following documents: (1) Federal Specification: L-P-375C—Plastic Film, Flexible....005-1: (Sheet 1) Cutting Pattern and General Arrangement (Adult). (Sheet 2) Alternate Stitching of Tapes and Webbing (Adult and Child). (Sheet 3) Pad Detail (Adult). (Sheet 4) Cutting Pattern and General...

17. INTAKE PIER, BRIDGE STRESS SHEET, SHEET 8 OF 117, ...

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

17. INTAKE PIER, BRIDGE STRESS SHEET, SHEET 8 OF 117, 1920. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA

76 FR 48122 - Polyethylene Terephthalate Film, Sheet, and Strip From Brazil: Preliminary Results of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-08

... Film, Sheet, and Strip From Brazil: Preliminary Results of Antidumping Duty Administrative Review... on polyethylene terephthalate film, sheet, and strip (PET film) from Brazil. This administrative... antidumping duty order on PET film from Brazil. See Polyethylene Terephthalate Film, Sheet, and Strip From...

75 FR 49900 - Polyethylene Terephthalate Film, Sheet, and Strip From Brazil: Preliminary Results of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-16

... Film, Sheet, and Strip From Brazil: Preliminary Results of Antidumping Duty Administrative Review... on polyethylene terephthalate film, sheet, and strip (PET film) from Brazil. This administrative... on PET film from Brazil. See Polyethylene Terephthalate Film, Sheet, and Strip From Brazil, the...

17 CFR 210.6-04 - Balance sheets.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Balance sheets. 210.6-04... 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Registered Investment Companies § 210.6-04 Balance sheets. This rule is applicable to balance sheets filed by registered investment companies except for...

14 CFR Section 3 - Chart of Balance Sheet Accounts

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Chart of Balance Sheet Accounts Section 3 Section 3 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... Balance Sheet Classifications Section 3 Chart of Balance Sheet Accounts [See footnotes at end of table...

49 CFR 1243.2 - Condensed balance sheet.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Condensed balance sheet. 1243.2 Section 1243.2... § 1243.2 Condensed balance sheet. Commencing with reports for the 3 months beginning January 1, 1972, and... hereby, required to compile and file quarterly reports of balance sheet items in accordance with...

49 CFR 1243.2 - Condensed balance sheet.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 9 2011-10-01 2011-10-01 false Condensed balance sheet. 1243.2 Section 1243.2... § 1243.2 Condensed balance sheet. Commencing with reports for the 3 months beginning January 1, 1972, and... hereby, required to compile and file quarterly reports of balance sheet items in accordance with...

14 CFR Section 3 - Chart of Balance Sheet Accounts

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Chart of Balance Sheet Accounts Section 3 Section 3 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... Balance Sheet Classifications Section 3 Chart of Balance Sheet Accounts [See footnotes at end of table...

17 CFR 210.6-04 - Balance sheets.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false Balance sheets. 210.6-04... 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Registered Investment Companies § 210.6-04 Balance sheets. This rule is applicable to balance sheets filed by registered investment companies except for...

Skill Sheets for Agricultural Mechanics.

ERIC Educational Resources Information Center

Iowa State Univ. of Science and Technology, Ames. Dept. of Agricultural Education.

This set of 33 skill sheets for agricultural mechanics was developed for use in high school and vocational school agricultural mechanics programs. Some sheets teach operational procedures while others are for simple projects. Each skill sheet covers a single topic and includes: (1) a diagram, (2) a step-by-step construction or operational…

17 CFR 229.1001 - (Item 1001) Summary term sheet.

Code of Federal Regulations, 2010 CFR

2010-04-01

... sheet that is written in plain English. The summary term sheet must briefly describe in bullet point format the most material terms of the proposed transaction. The summary term sheet must provide security... transaction. The bullet points must cross-reference a more detailed discussion contained in the disclosure...

75 FR 55340 - Recovery Fact Sheet 9580.100, Mold Remediation

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-10

...] Recovery Fact Sheet 9580.100, Mold Remediation AGENCY: Federal Emergency Management Agency, DHS. ACTION... accepting comments on Recovery Fact Sheet RP9580.100, Mold Remediation. DATES: Comments must be received by... 20472-3100. II. Background The Recovery Fact Sheet RP9580.100, Mold Remediation, identifies the expenses...

Ice-Sheet Dynamics and Millennial-Scale Climate Variability in the North Atlantic across the Middle Pleistocene Transition (Invited)

NASA Astrophysics Data System (ADS)

Hodell, D. A.; Nicholl, J.

2013-12-01

During the Middle Pleistocene Transition (MPT), the climate system evolved from a more linear response to insolation forcing in the '41-kyr world' to one that was decidedly non-linear in the '100-kyr world'. Smaller ice sheets in the early Pleistocene gave way to larger ice sheets in the late Pleistocene with an accompanying change in ice sheet dynamics. We studied Sites U1308 (49° 52.7'N, 24° 14.3'W; 3871 m) and U1304 (53° 3.4'N, 33° 31.8'W; 3024 m) in the North Atlantic to determine how ice sheet dynamics and millennial-scale climate variability evolved as glacial boundary conditions changed across the MPT. The frequency of ice-rafted detritus (IRD) in the North Atlantic was greater during glacial stages prior to 650 ka (MIS 16), reflecting more frequent crossing of an ice volume threshold when the climate system spent more time in the 'intermediate ice volume' window, resulting in persistent millennial scale variability. The rarity of Heinrich Events containing detrital carbonate and more frequent occurrence of IRD events prior to 650 ka may indicate the presence of 'low-slung, slippery ice sheets' that flowed more readily than their post-MPT counterparts (Bailey et al., 2010). Ice volume surpassed a critical threshold across the MPT that permitted ice sheets to survive boreal summer insolation maxima, thereby increasing ice volume and thickness, lengthening glacial cycles, and activating the dynamical processes responsible for Laurentide Ice Sheet instability in the region of Hudson Strait (i.e., Heinrich events). The excess ice volume during post-MPT glacial maxima provided a large, unstable reservoir of freshwater to be released to the North Atlantic during glacial terminations with the potential to perturb Atlantic Meridional Overtunring Circulation. We speculate that orbital- and millennial-scale variability co-evolved across the MPT and the interaction of processes on orbital and suborbital time scales gave rise to the changing patterns of glacial-interglacial cycles through the Quaternary. Bailey, I., Bolton, C.T., DeConto, R.M., Pollard, D., Schiebel, R. and Wilson, P.A. (2010) A low threshold for North Atlantic ice rafting from "low-slung slippery" late Pliocene ice sheets. Paleoceanography, 25, PA1212-[14pp]. (doi:10.1029/2009PA001736).

Positioning hospitals for improved access to capital.

PubMed

Ponton, Kevin T; Sandrick, Karen M

2002-11-01

Hospitals need to actively position themselves in the next 18 to 24 months to ensure continued access to financing. Hospitals need to shift their focus from investment income to operations. Hospitals should recognize the importance of balance-sheet liquidity to institutional investors. Not-for-profit hospitals should focus on both sides of the balance sheet. Healthcare executives need to develop effective leadership and investor-relations skills.

Making the Case: A Fact Sheet on Children and Youth in Out-of-School Time

ERIC Educational Resources Information Center

National Institute on Out of School Time, 2005

2005-01-01

This fact sheet resource is packed with the latest research and information on how children and youth spend their non-school hours, how they benefit from afterschool activities and much more. Sections include: (1) Children and youth today; (2) Health and well-being; (3) Children and youth spend time after school in a variety of ways; (4) Children…

What Works for Early Language and Literacy Development: Lessons from Experimental Evaluations of Programs and Intervention Strategies. Fact Sheet. Publication #2011-18

ERIC Educational Resources Information Center

Chrisler, Alison; Ling, Thomson

2011-01-01

Given the importance of the early childhood period as a time when the foundation is laid for later language and literacy, it is important to determine what activities and experiences lead to positive language and literacy outcomes in early childhood. This Fact Sheet reviews fifteen experimentally-evaluated programs and intervention strategies that…

"Lyle, Lyle, Crocodile": A New Musical Based on the Books by Bernard Waber. Cue Sheet for Teachers.

ERIC Educational Resources Information Center

Selwyn, Karen P.

This performance guide is designed for teachers to use with students before and after a performance of "Lyle, Lyle, Crocodile," a musical based on the books by Bernard Waber, with book by Michael Slade, music by David Evans, and lyrics by Mindi Dickstein. The guide, called a "Cuesheet," contains four activity sheets for use in…

Clinical Social Work. State Laws Governing Independent Practice and Reimbursement of Services. Fact Sheet for the Honorable Daniel K. Inouye, United States Senate.

ERIC Educational Resources Information Center

General Accounting Office, Washington, DC. Div. of Human Resources.

This fact sheet on state laws governing the independent practice and reimbursement of services for clinical social workers contains information from questionnaires sent to the state agencies responsible for health insurance regulations and Medicaid and licensing activities. Information on Ohio, the only state which did not respond, is not…

Fuels planning: science synthesis and integration; social issues fact sheet 14: Landscape preference in forested ecosystems

Treesearch

Christine Esposito

2006-01-01

It is important to understand what types of landscape settings most people prefer to be able to plan fuels treatment and other forest management activities that will be acceptable to the general public. This fact sheet considers the four common elements of visually preferred forest settings: large trees; herbacious, smooth groundcover; open midstory canopy; and vistas...

Solid phase extraction membrane

DOEpatents

Carlson, Kurt C [Nashville, TN; Langer, Roger L [Hudson, WI

2002-11-05

A wet-laid, porous solid phase extraction sheet material that contains both active particles and binder and that possesses excellent wet strength is described. The binder is present in a relatively small amount while the particles are present in a relatively large amount. The sheet material is sufficiently strong and flexible so as to be pleatable so that, for example, it can be used in a cartridge device.

Modelling the effects of ice-sheet activity on CO2 outgassing by Icelandic volcanoes

NASA Astrophysics Data System (ADS)

Armitage, J. J.; Ferguson, D.; Petersen, K. D.; Creyts, T. T.

2017-12-01

Glacial cycles may play a significant role in mediating the flux of magmatic CO2 between the Earth's mantle and atmosphere. In Iceland, it is thought that late-Pleistocene deglaciation led to a significant volcanic pulse, evidenced by increased post-glacial lava volumes and changes in melt chemistry consistent with depressurization. Investigating the extent to which glacial activity may have affected volcanic CO2 emissions from Iceland, and crucially over what timescale, requires detailed knowledge of how the magma system responded to the growth and collapse of the ice-sheet before and after the LGM. To investigate this, we coupled a model of magma generation and transport with a history of ice-sheet activity. Our results show that the emplacement and removal of the LGM ice-sheet likely led to two significant pulses of magmatic CO2. The first, and most significant of these, is associated with ice-sheet growth and occurs as the magma system recovers from glacial loading. This recovery happens from the base of the melting region upwards, producing a pulse of CO2 rich magma that is predicted to reach the surface around 20 ka after the loading event, close in time to the LGM. The second peak in CO2 output occurs abruptly following deglaciation as a consequence of increased rates of melt generation and transport in the shallow mantle. Although these post-glacial melts are relatively depleted in CO2, the increase in magma flux leads to a short-lived period of elevated CO2 emissions. Our results therefore suggest a negative feedback, whereby ice-sheet growth produces a delayed pulse of magmatic CO2, which, in addition to increased geothermal heat flux, may contribute towards driving deglaciation, which itself then causes further magmatism and CO2 outgassing. This model is consistent with the seismic structure of the asthenosphere below Iceland, and the established compositional and volumetric trends for sub- and post-glacial volcanism in Iceland. These trends show that the earliest subglacial events involved small volumes of enriched melts, while eruptions that were synchronous with or immediately followed deglaciation involved larger volumes of more depleted melts.

Perforating Thin Metal Sheets

NASA Technical Reports Server (NTRS)

Davidson, M. E.

1985-01-01

Sheets only few mils thick bonded together, punched, then debonded. Three-step process yields perforated sheets of metal. (1): Individual sheets bonded together to form laminate. (2): laminate perforated in desired geometric pattern. (3): After baking, laminate separates into individual sheets. Developed for fabricating conductive layer on blankets that collect and remove ions; however, perforated foils have other applications - as conductive surfaces on insulating materials; stiffeners and conductors in plastic laminates; reflectors in antenna dishes; supports for thermal blankets; lightweight grille cover materials; and material for mockup of components.

Preparation of Pt Ag alloy nanoisland/graphene hybrid composites and its high stability and catalytic activity in methanol electro-oxidation

PubMed Central

2011-01-01

In this article, PtAg alloy nanoislands/graphene hybrid composites were prepared based on the self-organization of Au@PtAg nanorods on graphene sheets. Graphite oxides (GO) were prepared and separated to individual sheets using Hummer's method. Graphene nano-sheets were prepared by chemical reduction with hydrazine. The prepared PtAg alloy nanomaterial and the hybrid composites with graphene were characterized by SEM, TEM, and zeta potential measurements. It is confirmed that the prepared Au@PtAg alloy nanorods/graphene hybrid composites own good catalytic function for methanol electro-oxidation by cyclic voltammograms measurements, and exhibited higher catalytic activity and more stability than pure Au@Pt nanorods and Au@AgPt alloy nanorods. In conclusion, the prepared PtAg alloy nanoislands/graphene hybrid composites own high stability and catalytic activity in methanol electro-oxidation, so that it is one kind of high-performance catalyst, and has great potential in applications such as methanol fuel cells in near future. PMID:21982417

Modeling the transition between upper plane bed regime and sheet flow without an active layer formulation. Preliminary results.

NASA Astrophysics Data System (ADS)

Viparelli, E.; Hernandez Moreira, R. R.; Blom, A.

2015-12-01

A perusal of the literature on bedload transport revealed that, notwithstanding the large number of studies on bedform morphology performed in the past decades, the upper plane bed regime has not been thoroughly investigated and the distinction between the upper plane bed and sheet flow transport regimes is still poorly defined. Previous experimental work demonstrated that the upper plane bed regime is characterized by long wavelength and small amplitude bedforms that migrate downstream. These bedforms, however, were not observed in experiments on sheet flow transport suggesting that the upper plane bed and the sheet flow are two different regimes. We thus designed and performed experiments in a sediment feed flume in the hydraulic laboratory of the Department of Civil and Environmental Engineering at the University of South Carolina at Columbia to study the transition from upper plane bed to sheet flow regime. Periodic measurements of water surface and bed elevation, bedform geometry and thicknesses of the bedload layer were performed by eyes, and with cameras, movies and a system of six ultrasonic probes that record the variations of bed elevation at a point over time. We used the time series of bed elevations to determine the probability functions of bed elevation. These probability functions are implemented in a continuous model of river morphodynamics, i.e. a model that does not use the active layer approximation to describe the sediment fluxes between the bedload and the deposit and that should thus be able to capture the details of the vertical and streamwise variation of the deposit grain size distribution. This model is validated against the experimental results for the case of uniform material. We then use the validated model in the attempt to study if and how the spatial distribution of grain sizes in the deposit changes from upper plane bed regime to sheet flow and if these results are influenced by the imposed rates of base level rise.

Whillans Ice Stream Subglacial Access Research Drilling (WISSARD): Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats (Invited)

NASA Astrophysics Data System (ADS)

Tulaczyk, S. M.; Anandakrishnan, S.; Behar, A. E.; Christner, B. C.; Fisher, A. T.; Fricker, H. A.; Holland, D. M.; Jacobel, R. W.; Mikucki, J.; Mitchell, A. C.; Powell, R. D.; Priscu, J. C.; Scherer, R. P.; Severinghaus, J. P.

2009-12-01

The WISSARD project is a large, NSF-funded, interdisciplinary initiative focused on scientific drilling, exploration, and investigation of Antarctic subglacial aquatic environments. The project consists of three interrelated components: (1) LISSARD - Lake and Ice Stream Subglacial Access Research Drilling, (2) RAGES - Robotic Access to Grounding-zones for Exploration and Science, and (3) GBASE - GeomicroBiology of Antarctic Subglacial Environments). A number of previous studies in West Antarctica highlighted the importance of understanding ice sheet interactions with water, either at the basal boundary where ice streams come in contact with active subglacial hydrologic and geological systems or at the marine margin where the ice sheet is exposed to forcing from the global ocean and sedimentation. Recent biological investigations of Antarctic subglacial environments show that they provide a significant habitat for life and source of bacterial carbon in a setting that was previously thought to be inhospitable. Subglacial microbial ecosystems also enhance biogeochemical weathering, mobilizing elements from long term geological storage. The overarching scientific objective of WISSARD is to examine the subglacial hydrological system of West Antarctica in glaciological, geological, microbiological, geochemical, and oceanographic contexts. Direct sampling will yield seminal information on these systems and test the overarching hypothesis that active hydrological systems connect various subglacial environments and exert major control on ice sheet dynamics, subglacial sediment transfer, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations and geological records of ice sheet history. Technological advances during WISSARD will provide the US-science community with a capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and it will be available for future use. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments.

Interfacial Strength and Physical Properties of Functionalized Graphene - Epoxy Nanocomposites

NASA Technical Reports Server (NTRS)

Miller, Sandi G.; Heimann, Paula; Scheiman, Daniel; Adamson, Douglas H.; Aksay, Iihan A.; Prud'homme, Robert K.

2006-01-01

The toughness and coefficient of thermal expansion of a series of functionalized graphene sheet - epoxy nanocomposites are investigated. Functionalized graphene sheets are produced by splitting graphite oxide into single graphene sheets through a rapid thermal expansion process. These graphene sheets contain approx. 10% oxygen due to the presence of hydroxide, epoxide, and carboxyl functional groups which assist in chemical bond formation with the epoxy matrix. Intrinsic surface functionality is used to graft alkyl amine chains on the graphene sheets, and the addition of excess hardener insures covalent bonding between the epoxide matrix and graphene sheets. Considerable improvement in the epoxy dimensional stability is obtained. An increase in nanocomposite toughness is observed in some cases.

Solid/melt interface studies of high-speed silicon sheet growth

NASA Technical Reports Server (NTRS)

Ciszek, T. F.

1984-01-01

Radial growth-rate anisotropies and limiting growth forms of point nucleated, dislocation-free silicon sheets spreading horizontally on the free surface of a silicon melt have been measured for (100), (110), (111), and (112) sheet planes. Sixteen-millimeter movie photography was used to record the growth process. Analysis of the sheet edges has lead to predicted geometries for the tip shape of unidirectional, dislocation-free, horizontally growing sheets propagating in various directions within the above-mentioned planes. Similar techniques were used to study polycrystalline sheets and dendrite propagation. For dendrites, growth rates on the order of 2.5 m/min and growth rate anisotropies on the order of 25 were measured.

Impact verification of space suit design for space station

NASA Technical Reports Server (NTRS)

Fish, Richard H.

1987-01-01

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

Fabrication method for cores of structural sandwich materials including star shaped core cells

DOEpatents

Christensen, Richard M.

1997-01-01

A method for fabricating structural sandwich materials having a core pattern which utilizes star and non-star shaped cells. The sheets of material are bonded together or a single folded sheet is used, and bonded or welded at specific locations, into a flat configuration, and are then mechanically pulled or expanded normal to the plane of the sheets which expand to form the cells. This method can be utilized to fabricate other geometric cell arrangements than the star/non-star shaped cells. Four sheets of material (either a pair of bonded sheets or a single folded sheet) are bonded so as to define an area therebetween, which forms the star shaped cell when expanded.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erkaev, N. V.; Siberian Federal University, Krasnoyarsk; Semenov, V. S.

A new kind of magnetohydrodynamic instability and waves are analyzed for a current sheet in the presence of a small normal magnetic field component varying along the sheet. These waves and instability are related to the existence of two gradients of the tangential (B{sub {tau}}) and normal (B{sub n}) magnetic field components along the normal ({nabla}{sub n}B{sub {tau}}) and tangential ({nabla}{sub {tau}}B{sub n}) directions with respect to the current sheet. The current sheet can be stable or unstable if the multiplication of two magnetic gradients is positive or negative. In the stable region, the kinklike wave mode is interpreted asmore » so-called flapping waves observed in Earth's magnetotail current sheet. The kink wave group velocity estimated for the Earth's current sheet is of the order of a few tens of kilometers per second. This is in good agreement with the observations of the flapping motions of the magnetotail current sheet.« less

Infused polymers for cell sheet release

NASA Astrophysics Data System (ADS)

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L.; Lin, Jennifer J.; Sutton, Amy; Aizenberg, Joanna

2016-05-01

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.

Effect of a large-sized silicone sheet upon recovery of mastoid aeration after mastoidectomy.

PubMed

Kazama, Kyosuke; Takahashi, Haruo; Kaieda, Satoru; Iwanaga, Tetsu; Yamamoto-Fukuda, Tomomi; Yoshida, Haruo; Kumagami, Hidetaka; Takasaki, Kenji

2008-06-01

To evaluate the effect of our large-sized silicone sheet upon postoperative recovery of mastoid aeration in ears after surgery including mastoidectomy and soft-wall reconstruction (SWR). Retrospective chart review in a tertiary care center. Recovery of mastoid aeration was assessed by CT 4 to 12 months after surgery on 72 ears (69 patients), in which the silicone sheet covering from the eustachian tube (ET) to the mastoid was placed after SWR procedure with mastoidectomy were done for their chronic otitis media. Results were compared with those with a small silicone sheet. Recovery of mastoid aeration was significantly better in the large-silicone-sheet group than in the small-silicone-sheet group (chi(2) value = 11.7146, P = 0.0006). This preliminary study suggested that our large-sized silicone sheet may be effective for postoperative recovery of mastoid aeration even in ears operated with SWR procedure.

Infused polymers for cell sheet release

PubMed Central

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L.; Lin, Jennifer J.; Sutton, Amy; Aizenberg, Joanna

2016-01-01

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering. PMID:27189419

Infused polymers for cell sheet release.

PubMed

Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L; Lin, Jennifer J; Sutton, Amy; Aizenberg, Joanna

2016-05-18

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.

Intermittent magnetic reconnection in TS-3 merging experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ono, Y.; Hayashi, Y.; Ii, T.

2011-11-15

Ejection of current sheet with plasma mass causes impulsive and intermittent magnetic reconnection in the TS-3 spherical tokamak (ST) merging experiment. Under high guide toroidal field, the sheet resistivity is almost classical due to the sheet thickness much longer than the ion gyroradius. Large inflow flux and low current-sheet resistivity result in flux and plasma pileup followed by rapid growth of the current sheet. When the pileup exceeds a critical limit, the sheet is ejected mechanically from the squeezed X-point area. The reconnection (outflow) speed is slow during the flux/plasma pileup and is fast during the ejection, suggesting that intermittentmore » reconnection similar to the solar flare increases the averaged reconnection speed. These transient effects enable the merging tokamaks to have the fast reconnection as well as the high-power reconnection heating, even when their current-sheet resistivity is low under high guide field.« less

Increases in plasma sheet temperature with solar wind driving during substorm growth phases

NASA Astrophysics Data System (ADS)

Forsyth, C.; Watt, C. E. J.; Rae, I. J.; Fazakerley, A. N.; Kalmoni, N. M. E.; Freeman, M. P.; Boakes, P. D.; Nakamura, R.; Dandouras, I.; Kistler, L. M.; Jackman, C. M.; Coxon, J. C.; Carr, C. M.

2014-12-01

During substorm growth phases, magnetic reconnection at the magnetopause extracts ~1015 J from the solar wind which is then stored in the magnetotail lobes. Plasma sheet pressure increases to balance magnetic flux density increases in the lobes. Here we examine plasma sheet pressure, density, and temperature during substorm growth phases using 9 years of Cluster data (>316,000 data points). We show that plasma sheet pressure and temperature are higher during growth phases with higher solar wind driving, whereas the density is approximately constant. We also show a weak correlation between plasma sheet temperature before onset and the minimum SuperMAG AL (SML) auroral index in the subsequent substorm. We discuss how energization of the plasma sheet before onset may result from thermodynamically adiabatic processes; how hotter plasma sheets may result in magnetotail instabilities, and how this relates to the onset and size of the subsequent substorm expansion phase.

Scanning light-sheet microscopy in the whole mouse brain with HiLo background rejection

PubMed Central

Mertz, Jerome; Kim, Jinhyun

2010-01-01

It is well known that light-sheet illumination can enable optically sectioned wide-field imaging of macroscopic samples. However, the optical sectioning capacity of a light-sheet macroscope is undermined by sample-induced scattering or aberrations that broaden the thickness of the sheet illumination. We present a technique to enhance the optical sectioning capacity of a scanning light-sheet microscope by out-of-focus background rejection. The technique, called HiLo microscopy, makes use of two images sequentially acquired with uniform and structured sheet illumination. An optically sectioned image is then synthesized by fusing high and low spatial frequency information from both images. The benefits of combining light-sheet macroscopy and HiLo background rejection are demonstrated in optically cleared whole mouse brain samples, using both green fluorescent protein (GFP)-fluorescence and dark-field scattered light contrast. PMID:20210471

Method for shaping sheet thermoplastic and the like

NASA Technical Reports Server (NTRS)

Akilian, Mireille K. (Inventor); Schattenburg, Mark L. (Inventor)

2011-01-01

Processes and apparati for shaping sheet glass or thermoplastic materials use force from a layer of a flowing fluid, such as air, between the sheet and a mandrel at close to the softening temperature of the thermoplastic. The shape is preserved by cooling. The shape of the air bearing mandrel and the pressure distribution of the fluid contribute to the final shape. A process can be conducted on one or two surfaces such that the force from the air layer is on one or two surfaces of the sheet. The gap size between the sheet and mandrel determines the pressure profile in the gap, which also determines the final sheet shape. In general, smaller gaps lead to larger viscous forces. The pressure profile depends on the shape of the mandrel, the size of the fluid gap and the sheet and the fluid supply pressure.

Large patternable metal nanoparticle sheets by photo/e-beam lithography

NASA Astrophysics Data System (ADS)

Saito, Noboru; Wang, Pangpang; Okamoto, Koichi; Ryuzaki, Sou; Tamada, Kaoru

2017-10-01

Techniques for micro/nano-scale patterning of large metal nanoparticle sheets can potentially be used to realize high-performance photoelectronic devices because the sheets provide greatly enhanced electrical fields around the nanoparticles due to localized surface plasmon resonances. However, no single metal nanoparticle sheet currently exists with sufficient durability for conventional lithographical processes. Here, we report large photo and/or e-beam lithographic patternable metal nanoparticle sheets with improved durability by incorporating molecular cross-linked structures between nanoparticles. The cross-linked structures were easily formed by a one-step chemical reaction; immersing a single nanoparticle sheet consisting of core metals, to which capping molecules ionically bond, in a dithiol ethanol solution. The ligand exchange reaction processes were discussed in detail, and we demonstrated 20 μm wide line and space patterns, and a 170 nm wide line of the silver nanoparticle sheets.

Thin sheets achieve optimal wrapping of liquids

NASA Astrophysics Data System (ADS)

Paulsen, Joseph; Démery, Vincent; Davidovitch, Benny; Santangelo, Christian; Russell, Thomas; Menon, Narayanan

2015-03-01

A liquid drop can wrap itself in a sheet using capillary forces [Py et al., PRL 98, 2007]. However, the efficiency of ``capillary origami'' at covering the surface of a drop is hampered by the mechanical cost of bending the sheet. Thinner sheets deform more readily by forming small-scale wrinkles and stress-focussing patterns, but it is unclear how coverage efficiency competes with mechanical cost as thickness is decreased, and what wrapping shapes will emerge. We place a thin (~ 100 nm) polymer film on a drop whose volume is gradually decreased so that the sheet covers an increasing fraction of its surface. The sheet exhibits a complex sequence of axisymmetric and polygonal partially- and fully- wrapped shapes. Remarkably, the progression appears independent of mechanical properties. The gross shape, which neglects small-scale features, is correctly predicted by a simple geometric approach wherein the exposed area is minimized. Thus, simply using a thin enough sheet results in maximal coverage.

Ultraviolet photodetectors based on ZnO sheets: The effect of sheet size on photoresponse properties

NASA Astrophysics Data System (ADS)

Ghasempour Ardakani, Abbas; Pazoki, Meysam; Mahdavi, Seyed Mohammad; Bahrampour, Ali Reza; Taghavinia, Nima

2012-05-01

In this work, ultraviolet photodetectors based on electrodeposited ZnO sheet thin films were fabricated on a glass substrate. Before electrodeposition, a thin buffer layer of ZnO was deposited on the glass by pulsed laser deposition method. This layer not only acted as a nucleation site for ZnO sheet growth, but also made it possible to use cheap glass substrate instead of conventional fluorine-doped tin oxide (FTO) substrate. Our results showed that photoresponse properties of the photodetectors strongly depend on the sheet sizes. The smaller sheets exhibited enhanced photosensitivity, shortened fall times and decreased gain compared to larger ones. We showed that photodetectors based on ZnO sheets have a faster response than ones based on polycrystalline films. It was also shown that even less response time could be obtained by using comb-like electrodes instead of two-electrode.

Increases in plasma sheet temperature with solar wind driving during substorm growth phases

PubMed Central

Forsyth, C; Watt, C E J; Rae, I J; Fazakerley, A N; Kalmoni, N M E; Freeman, M P; Boakes, P D; Nakamura, R; Dandouras, I; Kistler, L M; Jackman, C M; Coxon, J C; Carr, C M

2014-01-01

During substorm growth phases, magnetic reconnection at the magnetopause extracts ∼1015 J from the solar wind which is then stored in the magnetotail lobes. Plasma sheet pressure increases to balance magnetic flux density increases in the lobes. Here we examine plasma sheet pressure, density, and temperature during substorm growth phases using 9 years of Cluster data (>316,000 data points). We show that plasma sheet pressure and temperature are higher during growth phases with higher solar wind driving, whereas the density is approximately constant. We also show a weak correlation between plasma sheet temperature before onset and the minimum SuperMAG AL (SML) auroral index in the subsequent substorm. We discuss how energization of the plasma sheet before onset may result from thermodynamically adiabatic processes; how hotter plasma sheets may result in magnetotail instabilities, and how this relates to the onset and size of the subsequent substorm expansion phase. PMID:26074645

Increases in plasma sheet temperature with solar wind driving during substorm growth phases.

PubMed

Forsyth, C; Watt, C E J; Rae, I J; Fazakerley, A N; Kalmoni, N M E; Freeman, M P; Boakes, P D; Nakamura, R; Dandouras, I; Kistler, L M; Jackman, C M; Coxon, J C; Carr, C M

2014-12-28

During substorm growth phases, magnetic reconnection at the magnetopause extracts ∼10 15  J from the solar wind which is then stored in the magnetotail lobes. Plasma sheet pressure increases to balance magnetic flux density increases in the lobes. Here we examine plasma sheet pressure, density, and temperature during substorm growth phases using 9 years of Cluster data (>316,000 data points). We show that plasma sheet pressure and temperature are higher during growth phases with higher solar wind driving, whereas the density is approximately constant. We also show a weak correlation between plasma sheet temperature before onset and the minimum SuperMAG AL (SML) auroral index in the subsequent substorm. We discuss how energization of the plasma sheet before onset may result from thermodynamically adiabatic processes; how hotter plasma sheets may result in magnetotail instabilities, and how this relates to the onset and size of the subsequent substorm expansion phase.

Comparative study on predicting Young's modulus of graphene sheets using nano-scale continuum mechanics approach

NASA Astrophysics Data System (ADS)

Rafiee, Roham; Eskandariyun, Amirali

2017-06-01

In this research, nano-scale continuum modeling is employed to predict Young's modulus of graphene sheet. The lattice nano-structure of a graphene sheet is replaced with a discrete space-frame structure simulating carbon-carbon bonds with either beam or spring elements. A comparative study is carried out to check the influence of employed elements on estimated Young's moduli of graphene sheets in both horizontal and vertical directions. A detailed analysis is also conducted to investigate the influence of graphene sheet sizes on its Young's modulus and corresponding aspect ratios that unwelcomed end effects disappear on the results are extracted. At the final stage, defected graphene sheets suffering from vacancy defects are investigated through a stochastic analysis taking into account both number of defects and their locations as random parameters. The reduction level in the Young's moduli of defected graphene sheets compared with non-defected ones is analyzed and reported.

Ceramic substrate including thin film multilayer surface conductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolf, Joseph Ambrose; Peterson, Kenneth A.

2017-05-09

A ceramic substrate comprises a plurality of ceramic sheets, a plurality of inner conductive layers, a plurality of vias, and an upper conductive layer. The ceramic sheets are stacked one on top of another and include a top ceramic sheet. The inner conductive layers include electrically conductive material that forms electrically conductive features on an upper surface of each ceramic sheet excluding the top ceramic sheet. The vias are formed in each of the ceramic sheets with each via being filled with electrically conductive material. The upper conductive layer includes electrically conductive material that forms electrically conductive features on anmore » upper surface of the top ceramic sheet. The upper conductive layer is constructed from a stack of four sublayers. A first sublayer is formed from titanium. A second sublayer is formed from copper. A third sublayer is formed from platinum. A fourth sublayer is formed from gold.« less

Potential Climatic Effects on the Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Bindschadler, R. A.

1984-01-01

The Greenland Ice Sheet covers an area of 1,720,000 sq. km and contains approximately 2,600,000 cu km of ice. Most of the ice sheet receives an excess of snow accumulation over the amount of ice lost to wind, meltwater run-off or other ablative processes. The majority of mass loss occurs at the margin of the ice sheet as either surface melt, which flows into the sea or calving of icebergs from the tongues of outlet glaciers. Many estimates of these processes were published. An average of five published estimates is summarized. If these estimates are correct, then the Greenland Ice Sheet is in approximate equilibrium and contributes 490 cu km/a of fresh water to the North Atlantic and Arctic Oceans. Climate effects, ice sheet flow, and application of remote sensing to tracking of the ice sheet are discussed.

Evolution of tholeiitic diabase sheet systems in the eastern United States: examples from the Culpeper Basin, Virginia-Maryland, and the Gettysburg Basin, Pennsylvania

USGS Publications Warehouse

Woodruff, L.G.; Froelich, A.J.; Belkin, H.E.; Gottfried, D.

1995-01-01

High-TiO2, quartz-normative (HTQ) tholeiite sheets of Early Jurassic age have intruded mainly Late Triassic sedimentary rocks in several early Mesozoic basins in the eastern US. Field observations, petrographic study, geochemical analyses and stable isotope data from three HTQ sheet systems were used to develop a general model of magmatic differentiation and magmatic-hydrothermal interaction for HTQ sheets. The three sheet systems have remarkably similar major-oxide and trace-element compositions. Cumulus and evolved diabase in comagmatic sheets separated by tens of kilometers are related by igneous differentiation. Differentiated diabase in all three sheets have petrographic and geochemical signatures and fluid inclusions indicating hydrothermal alteration beginning near magmatic temperatures and continuing to relatively low temperatures. Sulfur and oxygen isotope data are consistent with a magmatic origin for the hydrothermal fluid. -from Authors

Effects of flow sheet implementation on physician performance in the management of asthmatic patients.

PubMed

Ruoff, Gary

2002-01-01

This project focused on increasing compliance, in a large family practice group, with quality indicators for the management of asthma. The objective was to determine if use of a flow sheet incorporating the Global Initiative for Asthma (GINA) guidelines could improve compliance with those guidelines if the flow sheet was placed in patients' medical records. After review and selection of 14 clinical quality indicators, physicians in the practice implemented a flow sheet as an intervention. These flow sheets were inserted into the records of 122 randomly selected patients with asthma. Medical records were reviewed before the flow sheets were placed in the records, and again approximately 6 months later, to determine if there was a change in compliance with the quality indicators. Improvement of documentation was demonstrated in 13 of the 14 quality indicators. The results indicate that compliance with asthma management quality indicators can improve with the use of a flow sheet.

Porous Ni3(NO3)2(OH)4 nano-sheets for supercapacitors: Facile synthesis and excellent rate performance at high mass loadings

NASA Astrophysics Data System (ADS)

Shi, Mingjie; Cui, Mangwei; Kang, Litao; Li, Taotao; Yun, Shan; Du, Jing; Xu, Shoudong; Liu, Ying

2018-01-01

For supercapacitors, pores in electrode materials can accelerate chemical reaction kinetics by shortening ion diffusion distances and by enlarging electrolyte/electrode interfaces. This article describes a simple one-step route for the preparation of pure-phase porous Ni3(NO3)2(OH)4 nano-sheets by directly heating a mild Ni(NO3)2 and urea solution. During heating, urea decomposed into NH3·H2O, which provided a suitable alkaline environment for the formation of Ni3(NO3)2(OH)4 nano-sheets. Meanwhile, the side product, NH4NO3, created numerous pores as a pore-forming agent. After NH4NO3 removal, the specific surface areas and pore volumes of products were boosted by ∼180-times (from 0.61 to 113.12 m2/g) and ∼90-times (from 3.40 × 10-3 to 3.17 × 10-1 m2/g), respectively. As a cathode material of supercapacitor, the porous Ni3(NO3)2(OH)4 nano-sheets exhibited a high specific capacitance of 1094 F/g at an ultrahigh mass loading of 17.55 mg/cm2, leading to an impressive areal capacitance of 19.2 F/cm2. Furthermore, a Ni3(NO3)2(OH)4 nano-sheet//commercial active carbon asymmetric supercapacitor was constructed and delivered an energy density of 33.2 Wh/Kg at a power density of 190.5 W/Kg, based on the mass of active materials on both electrodes.

Exploring Explanations of Subglacial Bedform Sizes Using Statistical Models.

PubMed

Hillier, John K; Kougioumtzoglou, Ioannis A; Stokes, Chris R; Smith, Michael J; Clark, Chris D; Spagnolo, Matteo S

2016-01-01

Sediments beneath modern ice sheets exert a key control on their flow, but are largely inaccessible except through geophysics or boreholes. In contrast, palaeo-ice sheet beds are accessible, and typically characterised by numerous bedforms. However, the interaction between bedforms and ice flow is poorly constrained and it is not clear how bedform sizes might reflect ice flow conditions. To better understand this link we present a first exploration of a variety of statistical models to explain the size distribution of some common subglacial bedforms (i.e., drumlins, ribbed moraine, MSGL). By considering a range of models, constructed to reflect key aspects of the physical processes, it is possible to infer that the size distributions are most effectively explained when the dynamics of ice-water-sediment interaction associated with bedform growth is fundamentally random. A 'stochastic instability' (SI) model, which integrates random bedform growth and shrinking through time with exponential growth, is preferred and is consistent with other observations of palaeo-bedforms and geophysical surveys of active ice sheets. Furthermore, we give a proof-of-concept demonstration that our statistical approach can bridge the gap between geomorphological observations and physical models, directly linking measurable size-frequency parameters to properties of ice sheet flow (e.g., ice velocity). Moreover, statistically developing existing models as proposed allows quantitative predictions to be made about sizes, making the models testable; a first illustration of this is given for a hypothesised repeat geophysical survey of bedforms under active ice. Thus, we further demonstrate the potential of size-frequency distributions of subglacial bedforms to assist the elucidation of subglacial processes and better constrain ice sheet models.

75 FR 69629 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Extension...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-15

... Film, Sheet, and Strip From the People's Republic of China: Extension of Time Limit for the Final... the initiation of the antidumping duty administrative review on polyethylene terephthalate film, sheet... the preliminary results of this review. See Polyethylene Terephthalate Film, Sheet, and Strip From the...

16 CFR 460.13 - Fact sheets.

Code of Federal Regulations, 2012 CFR

2012-01-01

... heat flow. The higher the R-value, the greater the insulating power. Compare insulation R-values before... INSULATION § 460.13 Fact sheets. If you are a manufacturer, you must give retailers and installers fact sheets for the insulation products you sell to them. Each sheet must contain what is listed here. You can...

16 CFR 460.13 - Fact sheets.

Code of Federal Regulations, 2010 CFR

2010-01-01

... heat flow. The higher the R-value, the greater the insulating power. Compare insulation R-values before... INSULATION § 460.13 Fact sheets. If you are a manufacturer, you must give retailers and installers fact sheets for the insulation products you sell to them. Each sheet must contain what is listed here. You can...

16 CFR 460.13 - Fact sheets.

Code of Federal Regulations, 2014 CFR

2014-01-01

... heat flow. The higher the R-value, the greater the insulating power. Compare insulation R-values before... INSULATION § 460.13 Fact sheets. If you are a manufacturer, you must give retailers and installers fact sheets for the insulation products you sell to them. Each sheet must contain what is listed here. You can...

16 CFR 460.13 - Fact sheets.

Code of Federal Regulations, 2013 CFR

2013-01-01

... heat flow. The higher the R-value, the greater the insulating power. Compare insulation R-values before... INSULATION § 460.13 Fact sheets. If you are a manufacturer, you must give retailers and installers fact sheets for the insulation products you sell to them. Each sheet must contain what is listed here. You can...

16 CFR 460.13 - Fact sheets.

Code of Federal Regulations, 2011 CFR

2011-01-01

... heat flow. The higher the R-value, the greater the insulating power. Compare insulation R-values before... INSULATION § 460.13 Fact sheets. If you are a manufacturer, you must give retailers and installers fact sheets for the insulation products you sell to them. Each sheet must contain what is listed here. You can...

46 CFR 160.002-1 - Incorporation by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... General Purpose, Natural or in Colors. (2) Federal Specification: L-P-375—Plastic Film, Flexible, Vinyl...: (Sheet 1) Cutting Pattern and General Arrangement (adult). (Sheet 1A) Alternate stitching of tapes and webbing (adult and child). (Sheet 2) Pad Detail (adult). Dwg. No. F-49-6-5: (Sheet 1) Cutting Pattern and...

46 CFR 160.002-1 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... General Purpose, Natural or in Colors. (2) Federal Specification: L-P-375—Plastic Film, Flexible, Vinyl...: (Sheet 1) Cutting Pattern and General Arrangement (adult). (Sheet 1A) Alternate stitching of tapes and webbing (adult and child). (Sheet 2) Pad Detail (adult). Dwg. No. F-49-6-5: (Sheet 1) Cutting Pattern and...