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1

Evaluating tall children.  

PubMed Central

The causes of tall stature are numerous; genetic tall stature and constitutional tall stature are the most common. Diagnosis can usually be established from the history and physical examination. An estimation of bone age can help to confirm diagnosis and to determine the child's growth potential. No treatment is usually necessary. Hormonal therapy can be considered for individuals for whom the predicted height is excessive if the psychosocial and medical advantages outweigh the risks of treatment. Images p462-a PMID:7773029

Leung, A. K.; Robson, W. L.

1995-01-01

2

New Approaches to Target T-ALL  

PubMed Central

Acute lymphoblastic leukemia is the most common malignancy in children. Although it is now curable in 80–90% of cases, patients with T-cell acute lymphoblastic leukemia (T-ALL) experience a higher frequency of induction failure and early relapse. Despite aggressive treatment approaches, including transplantation and new salvage regimens, most children with relapsed T-ALL will not be cured. As such, we are in need of new targeted therapies for the disease. Recent advances in the molecular characterization of T-ALL have uncovered a number of new therapeutic targets. This review will summarize recent advancements in the study of inhibiting the NOTCH1, PI3K–AKT, and Cyclin D3:CDK4/6 pathways as therapeutic strategies for T-ALL. We will focus on pre-clinical studies supporting the testing of small-molecule inhibitors targeting these proteins and the rationale of combination therapies. Moreover, epigenetic approaches to modulate T-ALL are rapidly emerging. Here, we will discuss the data supporting the role of bromodomain and extra-terminal bromodomain inhibitors in human T-ALL. PMID:25072021

Roti, Giovanni; Stegmaier, Kimberly

2014-01-01

3

Adaptive sampling strategies for efficient parameter scans in nano-photonic device simulations  

NASA Astrophysics Data System (ADS)

Rigorous optical simulations are an important tool in optimizing scattering properties of nano-photonic devices and are used, for example, in solar cell optimization. The finite element method (FEM) yields rigorous, timeharmonic, high accuracy solutions of the full 3D vectorial Maxwell's equations1 and furthermore allows for great flexibility and accuracy in the geometrical modeling of these often complex shaped 3D nano-structures. A major drawback of frequency domain methods is the limitation of single frequency evaluations. For example the accurate computation of the short circuit current density of an amorphous silicon/micro-crystalline multi-junction thin film solar cell may require the solution of Maxwell's equations for over a hundred different wavelengths if an equidistant sampling strategy is employed. Also in optical metrology, wavelength scans are frequently used to reconstruct unknown geometrical and material properties of optical systems numerically from measured scatterometric data. In our contribution we present several adaptive numerical integration and sampling routines and study their efficiency in the context of the determination of generation rate profiles of solar cells. We show that these strategies lead to a reduction in the computational effort without loss of accuracy. We discuss the employment of tangential information in a Hermite interpolation scheme to achieve similar accuracy on coarser grids. We explore the usability of these strategies for scatterometry and solar cell simulations.

Hammerschmidt, Martin; Pomplun, Jan; Burger, Sven; Schmidt, Frank

2014-03-01

4

Twisters, Tall Tales, & Science Teaching  

ERIC Educational Resources Information Center

Legends and tall tales have been part of the American culture for ages. Students are probably already familiar with the tales of how Pecos Bill fearlessly tamed a ferocious tornado, or Paul Bunyan effortlessly restrained a great river. Such tales have been passed down from generation to generation to explain humanity, the natural world, and…

Wilcox, Dawn Renee; Sterling, Donna R.

2006-01-01

5

MoMA: Tall Buildings  

NSDL National Science Digital Library

The Museum of Modern Art's (MoMA) project, Tall Buildings, addresses issues of technology, urbanism, and program for twenty five buildings designed within the last decade. This interactive website, designed with Macromedia Flash Player, allows users to compare the height, area, geographic locations, and program distribution. Users can learn about many design issues such as aerodynamics, green technologies, and public space. For each building, visitors can find a clear introduction and many images of floor plans and external views.

6

[Tall stature: some classical syndromes].  

PubMed

We describe the findings of XYY syndrome in the setting of encountering an individual with this particular condition in the endocrinology clinic. XYY syndrome is a relatively frequent if unfamiliar condition, which is characterized by taller than average height. The extra Y chromosome may play a role in determining the height of these individuals. From this case, a differential diagnosis of tall stature is outlined, in addition to a description of the principal syndromes associated with gigantism. These primarily include Klinefelter syndrome, Marfan syndrome, androgen resistance and growth hormone excess. These various entities are described from the point of view of their symptomatology, biology, pathophysiology and therapeutic characteristics. PMID:17020230

Gusbin, N; Verloes, A; Daly, A; Beckers, A

2006-01-01

7

Safe Emergency Evacuation From Tall Structures  

NASA Technical Reports Server (NTRS)

Emergency egress system allows people to be evacuated quickly from tall structures. New emergency system applicable to rescues from fires in tall hotels and other buildings. System consists of basket on slide wire. Basket descends by gravity on sloped slide wire staked to ground.

Stephan, E. S.

1984-01-01

8

Internal tide generation by tall ocean ridges  

E-print Network

Internal tides are internal waves of tidal period generated by tidal currents flowing over submarine topography. Tall ridges that are nominally two-dimensional (2-D) are sites of particularly strong generation. The subsequent ...

Echeverri Mondragón, Paula

2009-01-01

9

Tall Timbers Research Station: Research Programs  

NSDL National Science Digital Library

The Tall Timbers Research Station works to foster land stewardship through its research, conservation, and education efforts. Located in Tallahassee, Florida, the Tall Timbers Station conducts research in the areas of Fire Ecology, Resource Management, Vertebrate Ecology, Forestry, and Northern Bobwhite Quail studies. The Station's website contains overviews of its five major research programs and offers information regarding research jobs and internships. Tall Timbers also provides downloadable copies of its _Research Notes_ publication, and lists a variety of staff publications (some of which are downloadable). In addition, Tall Timbers features the E.V. Komarek Fire Ecology Database (reported on in the Scout Report for Science & Engineering, January 6, 1999) which contains approximately 15,000 citations, and 6,000 abstracts.

10

Host Status of Endophyte-Infected and Noninfected Tall Fescue Grass to Meloidogyne spp.  

PubMed Central

Tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to Meloidogyne incognita in the greenhouse. Tall fescue cultivars evaluated included, i) wild-type Jesup (E+, ergot-producing endophyte present), ii) endophyte-free Jesup (E-, no endophyte present), iii) Jesup (Max-Q, non-ergot producing endophyte) and iv) Georgia 5 (E+). Peach was included as the control. Peach supported greater (P ? 0.05) reproduction of M. incognita than all tall fescue cultivars. Differences in reproduction were not detected among the tall fescue cultivars and all cultivars were rated as either poor or nonhosts for M. incognita. Suppression of M. incognita reproduction was not influenced by endophyte status. In two other greenhouse experiments, host susceptibility of tall fescue grasses to two M. incognita isolates (BY-peach isolate and GA-peach isolate) did not appear to be related to fungal endophyte strain [i.e., Jesup (Max-Q; nontoxic endophyte strain) vs. Bulldog 51 (toxic endophyte strain)]. Host status of tall fescue varied with species of root-knot nematode. Jesup (Max-Q) was rated as a nonhost for M. incognita (BY-peach isolate and GA-peach isolate) and M. hapla, a poor host for M. javanica and a good host for M. arenaria. Bulldog 51 tall fescue was also a good host for M. arenaria and M. javanica, but not M. incognita. Jesup (Max-Q) tall fescue may have potential as a preplant control strategy for M. incognita and M. hapla in southeastern and northeastern United States, respectively. PMID:22736851

Meyer, S.L.F.

2010-01-01

11

Host status of endophyte-infected and noninfected tall fescue grass to Meloidogyne spp.  

PubMed

Tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to Meloidogyne incognita in the greenhouse. Tall fescue cultivars evaluated included, i) wild-type Jesup (E+, ergot-producing endophyte present), ii) endophyte-free Jesup (E-, no endophyte present), iii) Jesup (Max-Q, non-ergot producing endophyte) and iv) Georgia 5 (E+). Peach was included as the control. Peach supported greater (P ? 0.05) reproduction of M. incognita than all tall fescue cultivars. Differences in reproduction were not detected among the tall fescue cultivars and all cultivars were rated as either poor or nonhosts for M. incognita. Suppression of M. incognita reproduction was not influenced by endophyte status. In two other greenhouse experiments, host susceptibility of tall fescue grasses to two M. incognita isolates (BY-peach isolate and GA-peach isolate) did not appear to be related to fungal endophyte strain [i.e., Jesup (Max-Q; nontoxic endophyte strain) vs. Bulldog 51 (toxic endophyte strain)]. Host status of tall fescue varied with species of root-knot nematode. Jesup (Max-Q) was rated as a nonhost for M. incognita (BY-peach isolate and GA-peach isolate) and M. hapla, a poor host for M. javanica and a good host for M. arenaria. Bulldog 51 tall fescue was also a good host for M. arenaria and M. javanica, but not M. incognita. Jesup (Max-Q) tall fescue may have potential as a preplant control strategy for M. incognita and M. hapla in southeastern and northeastern United States, respectively. PMID:22736851

Nyczepir, A P; Meyer, S L F

2010-06-01

12

Typhoon effects on super-tall buildings  

NASA Astrophysics Data System (ADS)

Full-scale measurement is considered to be the most reliable method for evaluating wind effects on buildings and structures. This paper presents selected results of wind characteristics and structural responses measured from four super-tall buildings, The Center (350 m high, 79 floors) in Hong Kong, Di Wang Tower (384 m high, 78 floors) in Shenzhen, CITIC Plaza Tower (391 m high, 80 floors) in Guangzhou and Jin Mao Building (421 m high, 88 floors) in Shanghai, during the passages of three typhoons. The field data such as wind speed, wind direction and acceleration responses, etc., were continuously measured from the super-tall buildings during the typhoons. Detailed analysis of the field data was conducted to investigate the characteristics of typhoon-generated wind and wind-induced vibrations of these super-tall buildings under typhoon conditions. The dynamic characteristics of the tall buildings were determined from the field measurements and comparisons with those calculated from the finite element (FE) models of the structures were made. Furthermore, the full-scale measurements were compared with wind tunnel results to evaluate the accuracy of the model test results and the adequacy of the techniques used in the wind tunnel tests. The results presented in this paper are expected to be of considerable interest and of use to researchers and professionals involved in designing super-tall buildings.

Li, Q. S.; Xiao, Y. Q.; Wu, J. R.; Fu, J. Y.; Li, Z. N.

2008-06-01

13

Twisters, Tall Tales, and Science Teaching  

NSDL National Science Digital Library

Legends and tall tales have been part of the American culture for ages. Your students are probably already familiar with the tales of how Pecos Bill fearlessly tamed a ferocious tornado, or Paul Bunyan effortlessly restrained a great river. Such tales have been passed down from generation to generation to explain humanity, the natural world, and scientific phenomena. Harness your students' creative engery with this lesson that incorporates tall tales into the classroom, and follows the 5-E model (Engage, Explore, Explain, Elaborate, and Evaluate) for incorporating constructivism into science teaching.

Wilcox, Dawn R.; Sterling, Donna R.

2006-07-01

14

Drug name confusion: evaluating the effectiveness of capital (“Tall Man”) letters using eye movement data  

Microsoft Academic Search

Medication errors commonly involve confusion between drug names that look or sound alike. One possible method of reducing these errors is to print sections of the names in “Tall Man” (capital) letters, in order to emphasise differences between similar products. This paper reports an eye-tracking experiment that evaluates this strategy. Participants had their eye movements monitored while they searched for

Ruth Filik; Kevin Purdy; Alastair Gale; David Gerrett

2004-01-01

15

Analysis of Alongwind Tall Building Response to Transient Nonstationary Winds  

E-print Network

Analysis of Alongwind Tall Building Response to Transient Nonstationary Winds Xinzhong Chen1 Abstract: Transient nonstationary extreme winds such as thunderstorm downbursts are responsible tall building response to transient nonstationary winds based on nonstationary random vibration theory

Chen, Xinzhong

16

Dynamic interrelationship between technology and architecture in tall buildings  

E-print Network

The interrelationship between the technology and architecture of tall buildings is investigated from the emergence of tall buildings in the late 19th century to the present. Through the historical research, a filtering ...

Moon, Kyoung-Sun

2005-01-01

17

A Tall Tale: Laura Amy Schlitz  

ERIC Educational Resources Information Center

In this article, American author, children's librarian, and storyteller Laura Amy Schlitz is profiled. Schlitz is the winner of this year's Newbery Medal for her tall tale about the Mongols called "Gulnara the Tartar Warrior." Like her award-winning book, "Good Masters! Sweet Ladies!" (Candlewick, 2007), the tale takes place in the Middle Ages.…

Gallagher, Mary Grace

2008-01-01

18

Tall tower or mountain top measurements?  

NASA Astrophysics Data System (ADS)

Resolving the regional transport and distribution of greenhouse gases in the troposphere is a key topic that challenges both modelers and experimentalists. A dense network of measurement stations would be required, in particular including measurements at high elevation to better represent the entire lower troposphere, and not only small-scale local conditions in the near-surface atmosphere. While this can be achieved by tall towers, also mountain top stations (e.g. Schauinsland, Brocken) and other stations at high elevation (e.g., Mouna Loa, Jungfraujoch) are often appropriate, due to their extended concentration footprint. However, especially over complex, mountainous terrain, the transport of atmospheric gases and their spatio-temporal distribution is difficult to predict due to the development of thermally induced local wind patterns and boundary layer processes. Therefore, the main goal of our study is to test to what extend boundary layer processes at the surface and local wind patterns close to the ground at a mountain top site influence the ambient greenhouse gas patterns compared to measurements taken at a similar altitude but at a tall tower site. To this end we use measurements from the Zugerberg mountain top station, located at a pre-Alpine mountain ridge (987 m a.s.l., 4 m above ground) exposed to the prevailing synoptic winds in Switzerland, and compare these measurements with a neighboring tall tower site (Beromünster radio broadcast tower with its top at 1014 m a.s.l., 217 m above local ground level, and ?500 m above the Swiss Plateau). The Beromünster tall tower is located at a distance of only 30 km from the mountain top station as the bird flies, and hence a direct comparison minimizes confounding factors that are not related to the tall tower vs. mountain top position of the measurements. Both stations are part of the CarboCount CH greenhouse gas observation network (http://www.carbocount.ch) initiated for long-term monitoring and modeling of greenhouse gas fluxes at a regional scale in order to achieve a better understanding about CO2 and CH4 fluxes and their response to climate. We will present first direct comparisons of measurements obtained from continuously calibrated laser absorption spectrometers to quantify the atmospheric concentrations of carbon-dioxide and methane, but also from meteorological sensors and turbulence measurements. Data from the sensors at the two stations will be used to address the following question: can a mountain top station provide similar quality of data and spatial representativeness as a tall tower for the investigation of atmospheric patterns of greenhouse gases at diurnal to seasonal scale?

Bamberger, Ines; Eugster, Werner; Oney, Brian; Brunner, Dominik; Leuenberger, Markus; Schanda, Rüdiger; Henne, Stephan; Buchmann, Nina

2014-05-01

19

An experimental study of external reactor vessel cooling strategy on the critical heat flux using the graphene oxide nano-fluid  

SciTech Connect

External reactor vessel cooling (ERVC) for in-vessel retention (IVR) of corium as a key severe accident management strategy can be achieved by flooding the reactor cavity during a severe accident. In this accident mitigation strategy, the decay heat removal capability depends on whether the imposed heat flux exceeds critical heat flux (CHF). To provide sufficient cooling for high-power reactors such as APR1400, there have been some R and D efforts to use the reactor vessel with micro-porous coating and nano-fluids boiling-induced coating. The dispersion stability of graphene-oxide nano-fluid in the chemical conditions of flooding water that includes boric acid, lithium hydroxide (LiOH) and tri-sodium phosphate (TSP) was checked in terms of surface charge or zeta potential before the CHF experiments. Results showed that graphene-oxide nano-fluids were very stable under ERVC environment. The critical heat flux (CHF) on the reactor vessel external wall was measured using the small scale two-dimensional slide test section. The radius of the curvature is 0.1 m. The dimension of each part in the facility simulated the APR-1400. The heater was designed to produce the different heat flux. The magnitude of heat flux follows the one of the APR-1400 when the severe accident occurred. All tests were conducted under inlet subcooling 10 K. Graphene-oxide nano-fluids (concentration: 10 -4 V%) enhanced CHF limits up to about 20% at mass flux 50 kg/m{sup 2}s and 100 kg/m{sup 2}s in comparison with the results of the distilled water at same test condition. (authors)

Park, S. D.; Lee, S. W.; Kang, S.; Kim, S. M.; Seo, H.; Bang, I. C. [Ulsan National Inst. of Science and Technology UNIST, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulasn Metropolitan City 689-798 (Korea, Republic of)

2012-07-01

20

Vincristine could partly suppress stromal support to T-ALL blasts during pegylated arginase I treatment  

PubMed Central

Background Relapsed T-lineage acute lymphoblastic leukemia (T-ALL) has been an incurable disease. Recent reports showed that an L-arginine depleting enzyme, pegylated arginase (BCT-100) may be effective against T-ALL cells. On the other hand, studies including ours had shown the symbiosis of ALL blasts and human mesenchymal stromal cells (hMSCs) in bone marrow microenvironment during L-asparaginase treatment. As L-asparaginase and BCT-100 both act by depleting lymphoid cells of specific amino acid, we hypothesized that hMSCs may also protect T-ALL blasts from BCT-100 treatment in co-culture and such protection may be abrogated by pre-treating hMSCs with vincristine (VCR). Methods XTT assay was used to test sensitivities of T-ALL cell lines and hMSCs to BCT-100. Apoptosis of T-ALL cell lines with or without BCT-100 treatment were tested by annexin V / propidium iodide (AV/PI) assay using flow cytometer. Western blotting was performed to analyze the expression of ornithine transcarbamylase (OTC), an enzyme involved in L-arginine metabolism which may account for BCT-100 resistance. Results hMSCs were resistant to BCT-100 while CCRF-CEM, Jurkat and MOLT-4 were very sensitive to it. hMSCs could protect all the three cell lines from BCT-100 treatment in transwell co-culture. All the 3 T-ALL cell lines were also found to be rescued by an L-arginine precursor citrulline, while the breakdown product of BCT-100, ornithine only had limited salvaging effect on CCRF-CEM but not Jurkat and MOLT-4. Both hMSCs and 3 T-ALL cell lines express citrulline synthesis enzyme, ornithine transcarbamylase (OTC) at basal level while only hMSCs could express OTC at relatively higher level under BCT-100 treatment. Treating hMSCs with vincristine before co-culturing with T-ALL could resume the cytotoxicity of BCT-100 to CCRF-CEM and MOLT-4 cells. Conclusions Our results suggest a possible strategy to overcome resistance to BCT-100 from cancer microenvironments by suppressing hMSCs either in marrow or in the perivascular niche using vincristine. PMID:23574711

2013-01-01

21

Classic Papillary Thyroid Carcinoma with Tall Cell Features and Tall Cell Variant Have Similar Clinicopathologic Features  

PubMed Central

Background The tall cell variant of papillary thyroid carcinoma (TCVPTC) is more aggressive than classic papillary thyroid carcinoma (PTC), but the percentage of tall cells needed to diagnose TCVPTC remains controversial. In addition, little is known about the clinicopathologic features of classic PTC with tall cell features (TCF). Methods We retrospectively selected and reviewed the clinicopathologic features and presence of the BRAF mutation in 203 cases of classic PTC, 149 cases of classic PTC with TCF, and 95 cases of TCVPTCs, which were defined as PTCs having <10%, 10-50%, and ?50% tall cells, respectively. Results TCVPTCs and classic PTCs with TCF did not vary significantly in clinicopathologic characteristics such as pathologic (p) T stage, extrathyroidal extension, pN stage, lateral lymph node metastasis, or BRAF mutations; however, these features differed significantly in TCVPTCs and classic PTCs with TCF in comparison to classic PTCs. Similar results were obtained in a subanalysis of patients with microcarcinomas (?1.0 cm in size). Conclusions Classic PTCs with TCF showed a similar BRAF mutation rate and clinicopathologic features to TCVPTCs, but more aggressive characteristics than classic PTCs. PMID:25013418

Oh, Woo Jin; Lee, Young Sub; Cho, Uiju; Bae, Ja Seong; Lee, Sohee; Kim, Min Hee; Lim, Dong Jun; Park, Gyeong Sin; Lee, Youn Soo

2014-01-01

22

NANO EXPRESS Open Access Ultrafast nano-oscillators based on interlayer-  

E-print Network

NANO EXPRESS Open Access Ultrafast nano-oscillators based on interlayer- bridged carbon nanoscrolls nano-oscillators based on carbon nanoscrolls (CNSs) using molecular dynamics simulations. Initiated of gigahertz. We demonstrate an effective strategy to reduce the dissipation of the CNS-based nano

Li, Teng

23

Aerodynamic Admittance Function of Tall Buildings Ahsan Kareemb  

E-print Network

Aerodynamic Admittance Function of Tall Buildings Yin Zhoua Ahsan Kareemb a Malouf Engineering Int, Notre Dame, USA ABSTRACT: The aerodynamic admittance function (AAF) has been widely invoked to relate in the high frequency range were noted. KEYWORDS: Aerodynamic admittance function; Wind effects; Tall

Kareem, Ahsan

24

Numerical electromagnetic field analysis of lightning current in tall structures  

Microsoft Academic Search

The Numerical Electromagnetic Code (NEC-2) is applied to the electromagnetic analysis of tall structures hit by lightning. The advantage of the analysis using NEC-2 is that it can accurately compute the current distribution along a conductor system by the method of moments. The waveforms of the lightning currents measured on freestanding tall structures are well reproduced, and the computed waveforms

Yoshihiro Baba; Masaru Ishii

2001-01-01

25

Tall girls: the social shaping of a medical therapy.  

PubMed

During the latter half of the 20th century, estrogen therapy was administered to prevent otherwise healthy girls with tall stature from becoming tall adults by inhibiting further linear growth. We explore how decisions to treat tall girls with estrogen were influenced by both scientific knowledge and sociologic norms. Estrogen therapy represented the logical application of scientific knowledge regarding the role of estrogen for closure of the growth plates, but it also reflected prevailing societal and political beliefs about what it meant to be a tall girl. We discuss the rise and fall in popularity of this therapy and suggest that insight into the present-day treatment of short stature can be gained by comparing the use of estrogen therapy for tall girls with the use of growth hormone therapy for short boys. We suggest that this case study illustrates how scientific knowledge is always created and applied within a particular social context. PMID:17018462

Lee, Joyce M; Howell, Joel D

2006-10-01

26

Synthesis, structural characterization and selectively catalytic properties of metal-organic frameworks with nano-sized channels: A modular design strategy  

SciTech Connect

Modular design method for designing and synthesizing microporous metal-organic frameworks (MOFs) with selective catalytical activity was described. MOFs with both nano-sized channels and potential catalytic activities could be obtained through self-assembly of a framework unit and a catalyst unit. By selecting hexaaquo metal complexes and the ligand BTC (BTC=1,3,5-benzenetricarboxylate) as framework-building blocks and using the metal complex [M(phen){sub 2}(H{sub 2}O){sub 2}]{sup 2+} (phen=1,10-phenanthroline) as a catalyst unit, a series of supramolecular MOFs 1-7 with three-dimensional nano-sized channels, i.e. [M{sup 1}(H{sub 2}O){sub 6}].[M{sup 2}(phen){sub 2}(H{sub 2}O){sub 2}]{sub 2}.2(BTC).xH{sub 2}O (M{sup 1}, M{sup 2}=Co(II), Ni(II), Cu(II), Zn(II), or Mn(II), phen=1,10-phenanthroline, BTC=1,3,5-benzenetricarboxylate, x=22-24), were synthesized through self-assembly, and their structures were characterized by IR, elemental analysis, and single-crystal X-ray diffraction. These supramolecular microporous MOFs showed significant size and shape selectivity in the catalyzed oxidation of phenols, which is due to catalytic reactions taking place in the channels of the framework. Design strategy, synthesis, and self-assembly mechanism for the construction of these porous MOFs were discussed. - Grapical abstract: A modular design strategy has been developed to synthesize microporous metal-organic frameworks with potential catalytic activity by self-assembly of the framework-building blocks and the catalyst unit.

Qiu Lingguang [School of Chemistry and Chemical Engineering, Anhui University, 3rd, Feixi Road, Hefei 230039 (China)], E-mail: lgqiu@ahu.edu.cn; Gu Lina; Hu Gang [School of Chemistry and Chemical Engineering, Anhui University, 3rd, Feixi Road, Hefei 230039 (China); Zhang Lide [Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2009-03-15

27

Small Molecule that Reverses Dexamethasone Resistance in T-cell Acute Lymphoblastic Leukemia (T-ALL).  

PubMed

Glucocorticoids are one of the most utilized and effective therapies in treating T-cell acute lymphoblastic leukemia. However, patients often develop resistance to glucocorticoids, rendering these therapies ineffective. We screened 9517 compounds, selected for their lead-like properties, chosen from among 3?372?615 compounds, against a dexamethasone-resistant T-ALL cell line to identify small molecules that reverse glucocorticoid resistance. We synthesized analogues of the most effective compound, termed J9, from the screen in order to define the scaffold's structure-activity relationship. Active compounds restored sensitivity to glucocorticoids through upregulation of the glucocorticoid receptor. This compound and mechanism may provide a strategy for overcoming glucocorticoid resistance in patients with T-ALL. PMID:25050160

Cantley, Alexandra M; Welsch, Matthew; Ambesi-Impiombato, Alberto; Sanchez-Martin, Marta; Kim, Mi-Yeon; Bauer, Andras; Ferrando, Adolfo; Stockwell, Brent R

2014-07-10

28

Propagation of seismic waves in tall buildings  

USGS Publications Warehouse

A discrete-time wave propagation formulation of the seismic response of tall buildings is introduced. The building is modeled as a layered medium, similar to a layered soil medium, and is subjected to vertically propagating seismic shear waves. Soil layers and the bedrock under the foundation are incorporated in the formulation as additional layers. Seismic response is expressed in terms of the wave travel times between the layers, and the wave reflection and transmission coefficients at the layer interfaces. The equations account for the frequency-dependent filtering effects of the foundation and floor masses. The calculation of seismic response is reduced to a pair of simple finite-difference equations for each layer, which can be solved recursively starting from the bedrock. Compared to the commonly used vibration formulation, the wave propagation formulation provides several advantages, including simplified calculations, better representation of damping, ability to account for the effects of the soil layers under the foundation, and better tools for identification and damage detection from seismic records. Examples presented show the versatility of the method. ?? 1998 John Wiley & Sons, Ltd.

Safak, E.

1998-01-01

29

Interior of the second floor dance hall showing tall and ...  

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

Interior of the second floor dance hall showing tall and narrow window openings with 10-foot scale near center, looking south. - Bower Building, 409-413 East Weber Avenue, Stockton, San Joaquin County, CA

30

Wind pressure distribution on canopies attached to tall buildings  

Microsoft Academic Search

This paper presents the numerical simulations of wind pressure distributions on canopies attached to tall and medium-rise\\u000a buildings. The most current wind pressure coefficients in wind load codes do not take into account the large scale canopies\\u000a attached to tall and medium- rise L-shaped buildings. Wind pressure on canopies attached to buildings depends on the building\\u000a geometry and its features,

Hyung-Woon Roh; Ha-Rim Kim

2011-01-01

31

Ch08 oupTall Tales about Mind and Brain (Typeset by SPi, Delhi) July 12, 2006 18:34 Tall tales on intelligence  

E-print Network

Ch08 oup­Tall Tales about Mind and Brain (Typeset by SPi, Delhi) July 12, 2006 18:34 Tall tales on intelligence #12;Ch08 oup­Tall Tales about Mind and Brain (Typeset by SPi, Delhi) July 12, 2006 18:34 #12;Ch08 oup­Tall Tales about Mind and Brain (Typeset by SPi, Delhi) July 12, 2006 18:34 Chapter 8 Is bigger

Aberdeen, University of

32

Nano Waterproofing  

NSDL National Science Digital Library

This lesson focuses on how nanotechnology has impacted the design and engineering of many everyday items from paint to fabrics. Learners explore the hydrophobic effect and how similar properties can be introduced by reengineering products at the nano level. Learners work in teams to develop a waterproof material and compare their results with nano waterproof materials developed recently by engineers and scientists.

Ieee

2013-07-30

33

Carbon nanotubes: from nano test tube to nano-reactor.  

PubMed

Confinement of molecules and atoms inside carbon nanotubes provides a powerful strategy for studying structures and chemical properties of individual molecules at the nanoscale. In this issue of ACS Nano, Allen et al. explore the nanotube as a template leading to the formation of unusual supramolecular and covalent structures. The potential of carbon nanotubes as reactors for synthesis on the nano- and macroscales is discussed in light of recent studies. PMID:22200191

Khlobystov, Andrei N

2011-12-27

34

Body size and human energy requirements: Reduced mass-specific total energy expenditure in tall adults.  

PubMed

Mammalian resting energy expenditure (REE) increases as approximately weight(0.75) while mass-specific REE scales as approximately weight(-0.25). Energy needs for replacing resting losses are thus less relative to weight (W) in large compared with small mammals, a classic observation with biological implications. Human weight scales as approximately height(2) and tall adults thus have a greater weight than their short counterparts. However, it remains unknown if mass-specific energy requirements are less in tall adults; allometric models linking total energy expenditure (TEE) and weight with height (H) are lacking. We tested the hypothesis that mass-specific energy requirements scale inversely to height in adults by evaluating TEE (doubly labeled water) data collected by the National Academy of Sciences. Activity energy expenditure (AEE) was calculated from TEE, REE (indirect calorimetry), and estimated diet-induced energy expenditure. Main analyses focused on nonmorbidly obese subjects < or =50 yrs of age with non-negative AEE values (n = 404), although results were directionally similar for all samples. Allometric models, including age as a covariate, revealed significantly (P < 0.05) greater REE, AEE, and TEE as a function of height (range H(1.5-1.7)) in both men and women. TEE/W scaled negatively to height ( approximately H(-0.7), P < 0.01) with predicted mass-specific TEE (kcal/kg/d) at +/-2 SD for US height lower in tall compared with short men (40.3 vs. 46.5) and women (37.7 vs. 42.7). REE/W also scaled negatively to height in men (P < 0.001) and women (P < 0.01). Results were generally robust across several different analytic strategies. These observations reveal previously unforeseen associations between human stature and energy requirements that have implications for modeling efforts and provide new links to mammalian biology as a whole. PMID:19856424

Heymsfield, Steven B; Pietrobelli, Angelo

2010-01-01

35

A generalization of the Lucas addition chains Amadou TALL  

E-print Network

A generalization of the Lucas addition chains Amadou TALL tallamad@hotmail. com Cheikh Anta DIOP, a generalization of Lucas addition chains, where subtrac- tion is allowed, is given. It is called "Lucas addition be used to prove the optimality of Lucas addition chains for many cases. One of the main result

36

A generalization of the Lucas addition chains Amadou TALL  

E-print Network

A generalization of the Lucas addition chains Amadou TALL tallamad@hotmail. com Cheikh Anta DIOP, a generalization of Lucas addition chains, where subtrac­ tion is allowed, is given. It is called ''Lucas addition and will also be used to prove the optimality of Lucas addition chains for many cases. One of the main result

37

Wind Shear Characteristics at Central Plains Tall Towers (presentation)  

SciTech Connect

The objectives of this report are: (1) Analyze wind shear characteristics at tall tower sites for diverse areas in the central plains (Texas to North Dakota)--Turbines hub heights are now 70-100 m above ground and Wind measurements at 70-100+ m have been rare. (2) Present conclusions about wind shear characteristics for prime wind energy development regions.

Schwartz, M.; Elliott, D.

2006-06-05

38

Genetic diversity in a world germplasm collection of tall fescue.  

PubMed

Festuca arundinacea Schreb., commonly known as tall fescue, is a major forage crop in temperate regions. Recently, a molecular analysis of different accessions of a world germplasm collection of tall fescue has demonstrated that it contains different species from the genus Festuca and allowed their rapid classification into the three major morphotypes (Continental, Mediterranean and Rhizomatous). In this study, we explored the genetic diversity of 161 accessions of Festuca species from 29 countries, including 28 accessions of INTA (Argentina), by analyzing 15 polymorphic SSR markers by capillary electrophoresis. These molecular markers allowed us to detect a total of 214 alleles. The number of alleles per locus varied between 5 and 24, and the values of polymorphic information content ranged from 0.627 to 0.840. In addition, the accessions analyzed by flow cytometry showed different ploidy levels (diploid, tetraploid, hexaploid and octaploid), placing in evidence that the world germplasm collection consisted of multiple species, as previously suggested. Interestingly, almost all accessions of INTA germplasm collection were true hexaploid tall fescue, belonging to two eco-geographic races (Continental and Mediterranean). Finally, the data presented revealed an ample genetic diversity of tall fescue showing the importance of preserving the INTA collection for future breeding programs. PMID:23885206

Cuyeu, Romina; Rosso, Beatriz; Pagano, Elba; Soto, Gabriela; Fox, Romina; Ayub, Nicolás Daniel

2013-07-01

39

13. View looking south on Main Street. The tall building ...  

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

13. View looking south on Main Street. The tall building in the background on the right is the Metals Bank Building (1906), designed by Cass Gilbert. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

40

Process for tertiary oil recovery using tall oil pitch  

DOEpatents

A process and compositions for enhancing the recovery of acid crudes are disclosed. The process involves injecting caustic solutions into the reservoir to maintain a pH of 11 to 13. The fluid contains an effective amount of multivalent cation for inhibiting alkaline silica dissolution with the reservoir. A tall oil pitch soap is added as a polymeric mobility control agent. (DMC)

Radke, C.J.

1983-07-25

41

Phytoextraction of Zinc by Indian Mustard and Tall Fescue  

Microsoft Academic Search

This experiment evaluated the capacity of two species, Indian mustard (Brassica juncea Czern.) and tall fescue (Festuca arundinacea Schreb.) to extract zinc (Zn) from soils. Also, this experiment focused on using nitrogen (N) fertilizers to increase the phytoextraction of Zn. Two soils of the Hadley series (Typic Udifluvents) were studied. A treatment array of Zn concentrations in soils was supplied

Gretchen M. Bryson; Allen V. Barker

2007-01-01

42

Tall tales from de Sitter space II: Field theory dualities  

Microsoft Academic Search

We consider the evolution of massive scalar fields in (asymptotically) de Sitter spacetimes of arbitrary dimension. Through the proposed dS\\/CFT correspondence, our analysis points to the existence of new nonlocal dualities for the Euclidean conformal field theory. A massless conformally coupled scalar field provides an example where the analysis is easily explicitly extended to 'tall' background spacetimes.

Frédéric Leblond; Robert C. Myers

2003-01-01

43

Electromagnetic field radiation model for lightning strokes to tall structures  

Microsoft Academic Search

This paper describes observation and analysis of electromagnetic field radiation from lightning strokes to tall structures. Electromagnetic field waveforms and current waveforms of lightning strokes to the CN Tower have been simultaneously measured since 1991. A new calculation model of electromagnetic field radiation is proposed. The proposed model consists of the lightning current propagation and distribution model and the electromagnetic

H. Motoyama; W. Janischewskyj; A. M. Hussein; W. A. Chisholm; J. S. Chang; R. Rusan

1996-01-01

44

Building cost and eco-cost aspects of tall buildings  

Microsoft Academic Search

Compared to other countries, the Netherlands is hardly a leader in the development of tall buildings. Only a limited number of Dutch high rise projects have actually been realised. Numerous plans exist, however, making this a pertinent time to take building costs analysis to a higher level. A cost model is used to integrate and evaluate existing European research. The

Peter de Jong; Hans Wamelink

45

Physical processes during development of upward leaders from tall structures  

Microsoft Academic Search

The objective of our study was to identify and interpret the various processes during development of upward positive leaders from tall structures. We provide a physical interpretation for the varying luminosity of the leader channel during its initial ascent and the pulsing luminosity during much later stages of the established leader. Our analysis confirms that pulsed luminosity is a result

Vladislav Mazur; Lothar H. Ruhnke

2011-01-01

46

Genetic diversity in a world germplasm collection of tall fescue  

PubMed Central

Festuca arundinacea Schreb., commonly known as tall fescue, is a major forage crop in temperate regions. Recently, a molecular analysis of different accessions of a world germplasm collection of tall fescue has demonstrated that it contains different species from the genus Festuca and allowed their rapid classification into the three major morphotypes (Continental, Mediterranean and Rhizomatous). In this study, we explored the genetic diversity of 161 accessions of Festuca species from 29 countries, including 28 accessions of INTA (Argentina), by analyzing 15 polymorphic SSR markers by capillary electrophoresis. These molecular markers allowed us to detect a total of 214 alleles. The number of alleles per locus varied between 5 and 24, and the values of polymorphic information content ranged from 0.627 to 0.840. In addition, the accessions analyzed by flow cytometry showed different ploidy levels (diploid, tetraploid, hexaploid and octaploid), placing in evidence that the world germplasm collection consisted of multiple species, as previously suggested. Interestingly, almost all accessions of INTA germplasm collection were true hexaploid tall fescue, belonging to two eco-geographic races (Continental and Mediterranean). Finally, the data presented revealed an ample genetic diversity of tall fescue showing the importance of preserving the INTA collection for future breeding programs. PMID:23885206

Cuyeu, Romina; Rosso, Beatriz; Pagano, Elba; Soto, Gabriela; Fox, Romina; Ayub, Nicolas Daniel

2013-01-01

47

Wind Shear Characteristics at Central Plains Tall Towers  

SciTech Connect

The object of this study is to analyze wind shear characteristics at tall tower sites in the Central Plains of the United States. The hub heights of modern turbines used for wind farm projects are now 70 meters (m) to 100 m above ground and some advanced turbines under development for deployment during the second half of this decade are rated at 2-5 megawatts of energy generation with rotor diameters near 100 m and hub heights of 100-120 m. These advanced turbines will take advantage of the higher wind speeds aloft to generate more wind energy. Specific knowledge of important wind shear characteristics near and at turbine hub height is needed to optimize turbine design and wind farm layout. Unfortunately, wind speed shear measurements at heights of 80-120 m were virtually nonexistent a few years ago and are still quite uncommon today. The Central Plains is a prime wind energy development region and knowledge about the wind shear characteristics will reduce uncertainty about the resource and enhance wind farm design. Previous analyses of tall tower data (Schwartz and Elliott, 2005) concentrated on data from specific states. The wind energy community has recognized the need to fill the gap of direct wind speed measurements at levels 70 m and higher above the ground. Programs instituted during the last 5 years at the state level and supported by the U.S. Department of Energy's (DOE) State Energy Program initiative have placed anemometers and vanes at several levels on existing tall (70 m+) communication towers. The Central Plains has a fairly high concentration of tall tower sites. The distribution of tall tower sites varies among the states in the Central Plains, because the tall tower program is new and the available state and federal funding to establish tall towers is variable. Our wind resource assessment group at DOE's National Renewable Energy Laboratory (NREL) has obtained much of these necessary measurement data from both individual state sources and regional organizations. Most of the data are available to the public, though data from one tower in Colorado are proprietary. We have begun to analyze important wind climate parameters, including wind shear from the tall towers. A total of 13 tall towers were used for this study. Eleven of the towers had the highest anemometer level between 100 m and 113 m. Two towers had the highest measurement level between 70 m and 85 m above ground. The distribution of the towers among the states is: two sites in Texas and Oklahoma; six sites in Kansas; and one site each in Colorado, South Dakota, and North Dakota. Figure 1 shows the locations and names of the thirteen towers. The wind resource at these sites can be classified as ranging from good-to-excellent. Eight tall tower sites have Class 3 resource, four sites have Class 4 resource, and one has Class 5 resource at 50 m.

Schwartz, M.; Elliott, D.

2006-01-01

48

78 FR 76567 - Tall Oil, Polymer With Polyethylene Glycol and Succinic Anhydride Monopolyisobutylene Derivs...  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2013-0525; FRL-9903-19] Tall Oil, Polymer With Polyethylene Glycol and Succinic...a tolerance for residues of tall oil, polymer with polyethylene glycol and succinic...permissible level for residues of tall oil, polymer with polyethylene glycol and...

2013-12-18

49

Processes of recovering fatty acids and sterols from tall oil pitch  

SciTech Connect

An improved process of enhancing the recovery of fatty acids from tall oil pitch is disclosed. The process includes a hydrolysis step for increasing the free fatty acid available for recovery from tall oil pitch during the distillation process. The hydrolysis step also enables the recovery of sterols where the tall oil pitch is of the type which is rich in sterol esters.

Hughes, R. E.

1985-06-18

50

Understanding Nano  

NSDL National Science Digital Library

Nanotechnology can be a complicated topic. The Understanding Nano website is dedicated to providing clear and concise explanations of nanotechnology applications along with information on companies working in each area.

2013-07-05

51

Process for tertiary oil recovery using tall oil pitch  

DOEpatents

Compositions and process employing same for enhancing the recovery of residual acid crudes, particularly heavy crudes, by injecting a composition comprising caustic in an amount sufficient to maintain a pH of at least about 11, preferably at least about 13, and a small but effective amount of a multivalent cation for inhibiting alkaline silica dissolution with the reservoir. Preferably a tall oil pitch soap is included and particularly for the heavy crudes a polymeric mobility control agent.

Radke, Clayton J. (El Cerrito, CA)

1985-01-01

52

Improving tall fescue shade tolerance: identifying candidate genotypes  

Microsoft Academic Search

Tall fescue (Schedonorus arundinaceus [Schreb.] Dumort.) is genetically variable for many agronomic traits, so it might be possible to increase its persistence\\u000a and productivity in shaded agroforestry applications. The objective of this research was to identify high yielding, shade-tolerant\\u000a genotypes. Seed was obtained from eight families: seven plant introductions of European origin: 234718, 234720, 234882, 234884,\\u000a 235018, 235019, 235036, and

D. M. Burner; C. P. West

2010-01-01

53

Tall-Cell Variant of Papillary Thyroid Cancer: Disregarded Entity?  

Microsoft Academic Search

. The tall-cell variant of papillary thyroid carcinoma (TCV) has been described as an aggressive tumor with a significantly\\u000a higher incidence of recurrence and mortality than other forms of papillary carcinoma. In some series it has accounted for\\u000a up to 10%, whereas in other series it has not been reported at all, indicating that there are difficulties identifying it.\\u000a In

A. Rüter; R. Nishiyama; S. Lennquist

1997-01-01

54

Drug name confusion: evaluating the effectiveness of capital ("Tall Man") letters using eye movement data.  

PubMed

Medication errors commonly involve confusion between drug names that look or sound alike. One possible method of reducing these errors is to print sections of the names in "Tall Man" (capital) letters, in order to emphasise differences between similar products. This paper reports an eye-tracking experiment that evaluates this strategy. Participants had their eye movements monitored while they searched for a target product amongst an array of product packs. The target pack was replaced by a similar distractor in the array. Participants made fewer errors when the appearance of the names had been altered, that is, they were less likely to incorrectly identify a distractor as the target drug. This result was reflected in the eye movement data. PMID:15474212

Filik, Ruth; Purdy, Kevin; Gale, Alastair; Gerrett, David

2004-12-01

55

Strategis  

NSDL National Science Digital Library

Strategis is a web site developed by Industry Canada to provide business information resources to Canadian businesses. Resources available include a searchable database of Canadian companies, business information for each sector, a list of business support services, and a guide to business laws and regulation. The International Business Information Network offers information about business opportunities abroad; Trade Data Online provides Canadian and US trade data. A collection of research publications by Industry Canada and monthly economic indicators on the economy are additional economic resources found at this site. Users can view this site in French or English.

1998-01-01

56

Nano Letters  

NSDL National Science Digital Library

An electronic version of this journal from the American Chemical Society is available for free through June 30, 2001. Nano Letters is ACS's newest journal. It deals with "physical, chemical, and biological phenomena, processes and applications of structures within the nanoscale range."

57

NanoEd Resource Portal  

NSDL National Science Digital Library

From the National Center for Learning and Teaching in Nanoscale Science and Engineering, this educational site focuses on teaching resources in nanotechnology for high school and undergraduate students. The site is divided by resource type; visitors will find simulations and demonstrations, courses, lessons, and outside resources for integrating and introducing nanoscience into the classroom. The topics here range from carbon nanotubes, to magnetic force microscopes, to electrodeposition. Faculty are also encouraged to participate their own teaching materials to the project, and can find out more information by following the Contribute to NanoEd link.

2012-04-12

58

What is the concentration footprint of a tall tower?  

NASA Astrophysics Data System (ADS)

Studies that have attempted to estimate sources and sinks of trace gases such as CO2 with inverse calculations unanimously identify the lack of continental stations as a prime obstacle. Continental stations have traditionally been avoided because of the difficulty of interpretation due to large time-variability of trace substance mixing ratios. Large variability is caused by the proximity to the strongly variable sources in space and time and the complicated airflow within the lowermost 100-200 m of the planetary boundary layer. To address the need for continental stations and to overcome the problems associated with them, the National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory started in 1992 to measure CO2 and other trace gases on tall television transmission towers [Bakwin et al., 1995]. An essential question in connection with these tower measurements is the area around the tower from which fluxes substantially contribute to the observed short-term variability of trace gas mixing ratios. We present here a simple data and back trajectory-based method to estimate the fraction of the observed short-term variability explained by a localized flux around a tall television transmission tower in Wisconsin in dependence of its location relative to the tower (the concentration ``footprint''). We find that the timescale over which the imprint of surface fluxes on air parcels before its arrival at the tower are still discernible in the mixing ratio variations observed at the tower is of the order of 1.5 days. Based on this timescale and the characteristics of air parcel trajectories, we infer a spatial extent of the footprint of the order of 106km2, or roughly a tenth of the area of the United States. This is encouraging evidence that tall tower measurements may be useful in global inversions and may also have implications for monitoring fluxes of anthropogenic trace substances on regional scales.

Gloor, Manuel; Bakwin, Peter; Hurst, Dale; Lock, Loreen; Draxler, Roland; Tans, Pieter

59

Ground motion issues for seismic analysis of tall buildings: A status report  

USGS Publications Warehouse

The Pacific Earthquake Engineering Research Center (PEER) is coordinating a major multidisciplinary programme, the Tall Buildings Initiative (TBI), to address critical technical issues related to the design and analysis of new tall buildings located in coastal California. The authors of this paper, listed alphabetically, are involved in various research studies related to ground motion modelling, selection, modification and simulation for analysis of tall buildings. This paper summarizes the scope and progress of ongoing activities related to ground motion issues for response history analysis of tall buildings.

Bozorgnia, Y.; Campbell, K. W.; Luco, N.; Moehle, J. P.; Naeim, F.; Somerville, P.; Yang, T. Y.

2007-01-01

60

Development of methodology for alternative testing strategies for the assessment of the toxicological profile of nanoparticles used in medical diagnostics. NanoTEST - EC FP7 project  

NASA Astrophysics Data System (ADS)

Nanoparticles (NPs) have unique, potentially beneficial properties, but their possible impact on human health is still not known. The area of nanomedicine brings humans into direct contact with NPs and it is essential for both public confidence and the nanotech companies that appropriate risk assessments are undertaken in relation to health and safety. There is a pressing need to understand how engineered NPs can interact with the human body following exposure. The FP7 project NanoTEST (www.nanotest-fp7.eu) addresses these requirements in relation to the toxicological profile of NPs used in medical diagnostics.

Dusinska, Maria; Fjellsbo, Lise Maria; Heimstad, Eldbjorg; Harju, Mikael; Bartonova, Alena; Tran, Lang; Juillerat-Jeanneret, Lucienne; Halamoda, Blanka; Marano, Francelyne; Boland, Sonja; Saunders, Margaret; Cartwright, Laura; Carreira, Sara; Thawley, Susan; Whelan, Maurice; Klein, Christoph; Housiadas, Christos; Volkovova, Katarina; Tulinska, Jana; Beno, Milan; Sebekova, Katarina; Knudsen, Lisbeth E.; Mose, Tina; Castell, José V.; Vilà, Maya R.; Gombau, Lourdes; Jepson, Mark; Pojana, Giulio; Marcomini, Antonio

2009-05-01

61

Taking on the tall poles of autonomous robot navigation  

NASA Astrophysics Data System (ADS)

The Holy Grail of autonomous ground robotics has been to make ground vehicles that behave like humans. Over the years, as a community, we have realized the difficulty of this task, and we have back pedaled from the initial Holy Grail and have constrained and narrowed the domains of operation in order to get robotic systems fielded. This has lead to phrases such as "operation in structured environments" and "open-and-rolling terrain" in the context of autonomous robot navigation. Unfortunately, constraining the problem in this way has only put off the inevitable, i.e., solving the myriad of difficult robotics problems that we identified as long ago as the 1980's on the Autonomous Land Vehicle Project and in most cases are still facing today. These "Tall Poles" have included but are not limited to navigation through complex terrain geometry, navigation through thick vegetation, the detection of geometry-less obstacles such as negative obstacles and thin obstacles, the ability to deal with diverse and dynamic environmental conditions, the ability to function in dynamic and cluttered environments alongside other humans, and any combination of the above. This paper is an overview of the progress we have made at Autonomous Systems over the last three years in trying to knock down some of the tall poles remaining in the field of autonomous ground robotics.

Rosenblum, Mark; Rajagopalan, Venkat; Steinbis, John; Haddon, John; Cannon, Paul

2011-05-01

62

Development of Efficient Models of Corona Discharges Around Tall Structures  

NASA Astrophysics Data System (ADS)

This work concerns with numerical modeling of glow corona and sreamer corona discharges that occur near tall ground structures under thunderstorm conditions. Glow corona can occur when ambient electric field reaches modest values on the order of 0.2 kV/cm and when the electric field near sharp points of ground structure rises above a geometry dependent critical field required for ionization of air. Air is continuously ionized in a small region close to the surface of the structure and ions diffuse out into the surrounding air forming a corona. A downward leader approaching from a thundercloud causes a further increase in the electric field at the ground level. If the electric field rises to the point where it can support formation of streamers in air surrounding the tall structure, a streamer corona flash, or series of streamer corona flashes can be formed significantly affecting the space charge configuration formed by the preceding glow corona. The streamer corona can heat the surrounding air enough to form a self-propagating thermalized leader that is launched upward from the tall structure. This leader travels upward towards the thundercloud and connects with the downward approaching leader thus causing a lightning flash. Accurate time-dependent modeling of charge configuration created by the glow and streamer corona discharges around tall structure is an important component for understanding of the sequence of events leading to lightning attachment to the tall structure. The present work builds on principal modeling ideas developed previously in [Aleksandrov et al., J. Phys. D: Appl. Phys., 38, 1225, 2005; Bazelyan et al., Plasma Sources Sci. Technol., 17, 024015, 2008; Kowalski, E. J., Honors Thesis, Penn State Univ., University Park, PA, May 2008; Tucker and Pasko, NSF EE REU Penn State Annual Res. J., 10, 13, 2012]. The non-stationary glow and streamer coronas are modeled in spherical geometry up to the point of initiation of the upward leader. The model uses an implicit numerical scheme for time integration and employs effective non-uniform grid system allowing very accurate description of non-stationary coronas emitted by sharp points with sub-millimeter dimensions and expanding hundreds of meters in surrounding air. In the talk we will present principal components of the model and its performance under different time dynamics of the applied electric field closely resembling scenarios under thunderstorm conditions, including, in particular, extended periods of time (tens of seconds) when only glow corona is produced, followed by a fast rise in the field (tens of microseconds) describing approach of the downward leader. We will also present comparisons of the numerical model results on time dependent corona radius and current with an analytical corona theory summarized recently by Bazelyan et al. [2008].

Tucker, J.; Pasko, V. P.

2012-12-01

63

Nano-storage wires.  

PubMed

We report the development of "nano-storage wires" (NSWs), which can store chemical species and release them at a desired moment via external electrical stimuli. Here, using the electrodeposition process through an anodized aluminum oxide template, we fabricated multisegmented nanowires composed of a polypyrrole segment containing adenosine triphosphate (ATP) molecules, a ferromagnetic nickel segment, and a conductive gold segment. Upon the application of a negative bias voltage, the NSWs released ATP molecules for the control of motor protein activities. Furthermore, NSWs can be printed onto various substrates including flexible or three-dimensional structured substrates by direct writing or magnetic manipulation strategies to build versatile chemical storage devices. Since our strategy provides a means to store and release chemical species in a controlled manner, it should open up various applications such as drug delivery systems and biochips for the controlled release of chemicals. PMID:23859333

Lee, Dong Jun; Kim, Eunji; Kim, Daesan; Park, Juhun; Hong, Seunghun

2013-08-27

64

Lightning strikes to tall objects: Currents inferred from far electromagnetic fields versus directly measured currents  

E-print Network

Lightning strikes to tall objects: Currents inferred from far electromagnetic fields versus-field-to-current conversion factors for lightning strikes to tall objects for (1) the initial peak current at the object top by lightning detection networks and are each expressed here as the product of (a) the far

Florida, University of

65

Lightning electromagnetic environment in the presence of a tall grounded strike object  

E-print Network

Lightning electromagnetic environment in the presence of a tall grounded strike object Yoshihiro have analyzed and compared distance dependences of electric and magnetic fields due to a lightning strike to a tall object and due to the same lightning strike to flat ground. In both cases, lightning

Florida, University of

66

SULFUR SOURCE AND PLACEMENT FOR NEWLY ESTABLISHED ENDOPHYTE-FREE TALL FESCUE  

Microsoft Academic Search

Previous research indicated that tall fescue (Festuca arundinacea Schreb.) may respond to sulfur (S) fertilization. However, data are limited concerning S management options to improve yield and quality of newly-established, endophyte-free tall fescue. Thus, a field study was conducted from 1989 to 1991 to determine the effects of S source (ammonium thiosulfate [ATS] and ammonium sulfate [AS]); rate (17 and

Daniel W. Sweeney; Joseph L. Moyer

2001-01-01

67

Real-Time Eulerian Water Simulation Using a Restricted Tall Cell Grid Nuttapong Chentanez Matthias Muller  

E-print Network

Real-Time Eulerian Water Simulation Using a Restricted Tall Cell Grid Nuttapong Chentanez Matthias physics and rendering. Water flows from the left into an uneven terrain. The tall cells (below the orange line) represent the major part of the water volume while the computation is focused to the surface area

Müller-Fischer, Matthias

68

Tall Poppies: Bullying Behaviors Faced by Australian High-Performance School-Age Athletes  

ERIC Educational Resources Information Center

Little is known about Australian high-performance school-age athletes' experiences as victims of the tall poppy syndrome. Tall poppies are successful individuals bullied by those who are less successful in order to "normalize them." Nineteen current or previous national or international high-performance school-age athletes were…

O'Neill, Maureen; Calder, Angela; Allen, Bill

2014-01-01

69

A Qualitative Perspective of Tall College Women's Intrinsic Dynamics Relating to Height  

ERIC Educational Resources Information Center

We conducted in-depth interviews with 24 tall college females for the present phenomenological, qualitative research study. As tall females in our study described the impact of height on their self-perceptions, two over-arching key height-related outcomes emerged, each of which contained sub-components. First, participants described themselves as…

Firmin, Michael W.; Hoffman, Sarah J.; Firmin, Ruth L.; Lee, Alisha D.; Vorobyov, Yelana

2013-01-01

70

21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.  

... 2014-04-01 2014-04-01 false Oleic acid derived from tall oil fatty acids. 172.862 Section 172.862 Food and Drugs...CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food...

2014-04-01

71

Evolutionary diversification of fungal endophytes of tall fescue grass by hybridization with Epichlo? species.  

PubMed Central

The mutualistic associations of tall fescue (Festuca arundinacea) with seed-borne fungal symbionts (endophytes) are important for fitness of the grass host and its survival under biotic and abiotic stress. The tall fescue endophytes are asexual relatives of biological species (mating populations) of genus Epichloë (Clavicipitaceae), sexual fungi that cause grass choke disease. Isozyme studies have suggested considerable genetic diversity among endophytes of tall fescue. Phylogenetic relationships among seven isolates from tall fescue, three from meadow fescue (a probable ancestor of tall fescue), and nine Epichloë isolates from other host species were investigated by comparing sequences of noncoding segments of the beta-tubulin (tub2) and rRNA (rrn) genes. Whereas each Epichloë isolate and meadow fescue endophyte had only a single tub2 gene, most tall fescue endophytes had two or three distinct tub2 copies. Phylogenetic analysis of tub2 sequences indicated that the presence of multiple copies in the tall fescue endophytes was a consequence of hybridization with Epichloë species. At least three hybridization events account for the distribution and relationships of tub2 genes. These results suggest that interspecific hybridization is the major cause of genetic diversification of the tall fescue endophytes. Images PMID:8172623

Tsai, H F; Liu, J S; Staben, C; Christensen, M J; Latch, G C; Siegel, M R; Schardl, C L

1994-01-01

72

method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings Skol  

EPA Pesticide Factsheets

Search instead for method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings method estimate certain losses related identification assessment ground acceleration structural parameters improve prediction mortality tall buildings Skol ?

73

Alternative fuel properties of tall oil fatty acid methyl ester-diesel fuel blends.  

PubMed

In this experimental work, tall oil methyl ester-diesel fuel blends as alternative fuels for diesel engines were studied. Tall oil methyl ester was produced by reacting tall oil fatty acids with methyl alcohol under optimum conditions. The blends of tall oil methyl ester-diesel fuel were tested in a direct injection diesel engine at full load condition. The effects of the new fuel blends on the engine performance and exhaust emission were tested. It was observed that the engine torque and power output with tall oil methyl ester-diesel fuel blends increased up to 6.1% and 5.9%, respectively. It was also seen that CO emissions decreased to 38.9% and NO(x) emissions increased up to 30% with the new fuel blends. The smoke opacity did not vary significantly. PMID:16524723

Altiparmak, Duran; Keskin, Ali; Koca, Atilla; Gürü, Metin

2007-01-01

74

Pollination in Verbascum thapsus (Scrophulariaceae): the advantage of being tall.  

PubMed

According to the "effective pollination" hypothesis, tall stature resulting from strong apical dominance attracts greater pollinator visitation, thus allowing larger pollen loads and/or greater outcrossing rates, which in turn produces more vigorous offspring with greater genotypic variability and/or less inbreeding depression. Components of this hypothesis were tested in Verbascum thapsus, which commonly grows unbranched to over 2 m tall with strong apical dominance suppressing all axillary meristems. A natural population survey indicated that plants with visiting pollinators were significantly taller than their nearest neighboring individuals not possessing a visiting pollinator. Plants in natural populations with excluded pollinators produced seeds via a delayed selfing mechanism. However, delayed selfing under pollinator exclusion resulted in only 75% of the seed set obtained with natural pollinators. Under natural pollination, emasculated flowers experienced a 50% reduction in pollen deposition by the time of flower closure but only a 5% reduction in seed set relative to intact flowers. Hence, taller plants attracted more pollinators and maximum seed set could not be achieved without pollinators. Comparison of seed set and seed mass in plants that were artificially selfed and artificially crossed (in both the greenhouse and in natural populations) indicated that plants were fully self-compatible with no evidence of early-acting inbreeding depression. However, this does not exclude the possibility that inbreeding depression is manifested in later life stages. The results suggest that V. thapsus has a mixed mating system with potential for reproductive assurance and various levels of outcrossing depending on variables affecting pollinator availability (e.g., population size). PMID:21680322

Donnelly, S E; Lortie, C J; Aarssen, L W

1998-11-01

75

caNanoLab  

Cancer.gov

QUICK LINKS NCI caNanoLab Wiki NCI CBIIT Home NCL Home NCL CSN Home NCI Nano Alliance Home NCI Home EXTERNAL  Disclaimer NBI NIOSH NIL InterNano nanoHUB ICON SAFENANO HOME PROTOCOLS SAMPLES PUBLICATIONS HELP GLOSSARY LOGIN Search Protocols Help

76

Nano-technology and nano-toxicology  

PubMed Central

Rapid developments in nano-technology are likely to confer significant benefits on mankind. But, as with perhaps all new technologies, these benefits are likely to be accompanied by risks, perhaps by new risks. Nano-toxicology is developing in parallel with nano-technology and seeks to define the hazards and risks associated with nano-materials: only when risks have been identified they can be controlled. This article discusses the reasons for concern about the potential effects on health of exposure to nano-materials and relates these to the evidence of the effects on health of the ambient aerosol. A number of hypotheses are proposed and the dangers of adopting unsubstantiated hypotheses are stressed. Nano-toxicology presents many challenges and will need substantial financial support if it is to develop at a rate sufficient to cope with developments in nano-technology. PMID:22662021

Maynard, Robert L.

2012-01-01

77

Decay resistance of wood treated with boric acid and tall oil derivates.  

PubMed

In this study, the effect of two boric acid concentrations (1% and 2%) and four derivates of tall oil with varying chemical composition were tested separately and in combination. The tall oil derivates were chosen in a way that they consist of different amounts of free fatty, resin acids and neutral compounds. Decay tests using two brown rot fungi (Postia placenta and Coniophora puteana) were performed on both unleached and leached test samples. Boric acid showed a low weight loss in test samples when exposed to fungal decay before leaching, but no effect after leaching. The tall oil derivates gave better efficacy against decay fungi compared to control, but are not within the range of the efficacy needed for a wood preservative. Double impregnation with boric acid and tall oil derivates gave synergistic effects for several of the double treatments both in unleached and leached samples. In the unleached samples the double treatment gave a better efficacy against decay fungi than tall oil alone. In leached samples a better efficacy against brown rot fungi were achieved than in samples with boron alone and a nearly similar or better efficacy than for tall oil alone. Boric acid at 2% concentration combined with the tall oil derivate consisting of 90% free resin acids (TO-III) showed the best performance against the two decay fungi with a weight loss less than 3% after a modified pure culture test. PMID:17931858

Temiz, Ali; Alfredsen, Gry; Eikenes, Morten; Terziev, Nasko

2008-05-01

78

FLUX MEASUREMENTS FROM A TALL TOWER IN A COMPLEX LANDSCAPE  

SciTech Connect

The accuracy and representativeness of flux measurements from a tall tower in a complex landscape was assessed by examining the vertical and sector variability of the ratio of wind speed to momentum flux and the ratio of vertical advective to eddy flux of heat. The 30-60 m ratios were consistent with theoretical predictions which indicate well mixed flux footprints. Some variation with sector was observed that were consistent with upstream roughness. Vertical advection was negligible compared with vertical flux except for a few sectors at night. This implies minor influence from internal boundary layers. Flux accuracy is a function of sector and stability but 30-60 m fluxes were found to be generally representative of the surrounding landscape. This paper will study flux data from a 300 m tower, with 4 levels of instruments, in a complex landscape. The surrounding landscape will be characterized in terms of the variation in the ratio of mean wind speed to momentum flux as a function of height and wind direction. The importance of local advection will be assessed by comparing vertical advection with eddy fluxes for momentum and heat.

Kurzeja, R.; Weber, A.; Chiswell, S.; Parker, M.

2010-07-22

79

[Testosteron treatment of excessively tall boys (author's transl)].  

PubMed

Twenty-five boys aged 11.7-16.8 years with constitutionally tall stature were treated with 500 mg testosteron oenanthate two-weekly over a period of 15.6 months on average. Prediction of height was done according to Bayley-Pinneau (BP) and Tanner et al. with a mean parent height of 168 cm (T168) and 172 cm (T172). It was on average at 202.73 cm (BP) and 203.26 cm (T168) or 201.97 (T172). The achieved height reduction was 7.2 cm (BP), 7.73 cm (T168) and 6.44 cm (T172), corresponding to a reduction of 45.6% (BP), 47.3% (T168) and 41% (T172) of the future growth. Whereas the major reductions were obtained in the youngest patients, success of treatment in patients with a skeletal age of 15 and more years was not demonstrable with certainty. Predominant side effects were weight gain within the first 6 months, acne and transient reduction of testicular volume. PMID:6458488

Brämswig, J H; Schellong, G; Borger, H J; Breu, H

1981-12-01

80

Amended safety assessment of tall oil acid, sodium tallate, potassium tallate, and ammonium tallate.  

PubMed

Tall oil acid is a mixture of oleic and linoleic acids (fatty acids) and rosin acids derived from tall oil, a by-product of pulp from resinous woods, used in cosmetic products as a surfactant at concentrations up to 8%. Ammonium, potassium, and sodium salts also are listed as cosmetic ingredients. In addition to the studies summarized in this report, extensive toxicity, genotoxicity, and carcinogenicity studies in animals are available for oleic, lauric, palmitic, myristic, and stearic fatty acids as published earlier by the Cosmetic Ingredient Review (CIR). These data may be extrapolated to tall oil acid and its salts. There are no reports of current uses or use concentration data for ammonium tallate, nor are use concentration data available for the other salts. The CIR Expert Panel found tall oil acid, ammonium tallate, potassium tallate, and sodium tallate to be safe cosmetic ingredients in the given practices of use and concentration. PMID:20086195

Robinson, Valerie; Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F

2009-01-01

81

The role of the aerodynamic modifications of the shapes of tall buildings  

E-print Network

With the advances in technology, recent tall building design has undergone a shift to the free-style geometric forms in the exuberant and liberal atmosphere. As a height of the building increases, it is more susceptible ...

Lee, Jooeun, S.M. Massachusetts Institute of Technology

2011-01-01

82

Does a toxic fungal endophyte of tall fescue affect reproduction of  

E-print Network

of egg infertility and poor hatching success. Despite extensive surveys, tall fescue was not observed (Bunin et al. 1997; Jamieson & Ryan 2000). The majority of egg failures result from high egg infertility

Jamieson, Ian

83

Tall buildings in Asia : a critique on the high-rise building in Colombo, Shri Lanka  

E-print Network

The recent generation of tall buildings in Asia have been appropriated from the West with little adaptation. With no understanding of the forces that have generated this building form, Asia embraces the high-rise as an ...

Pieris, Anoma D. (Anoma Darshani)

1993-01-01

84

Grazing management and pasture production of tall fescue-legume mixtures in dryland pastures.  

E-print Network

??Pasture production and composition and liveweight gain of sheep grazing tall fescue-clover and perennial ryegrass-clover dryland pastures at Lincoln, Canterbury was examined in four experiments… (more)

Jusoh, Shokri

2013-01-01

85

Relative effects of irrigation and intense shade on productivity of alley-cropped tall fescue herbage  

Microsoft Academic Search

The relative effects of irradiance and soil water on alley-cropped herbage are poorly understood. Our objective was to determine\\u000a effects of irrigation on herbage productivity when tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] was grown in two sites, a meadow and a loblolly pine (Pinus taeda L.) alley (620 trees ha?1), near Booneville, Arkansas. Three tall fescue entries were space planted in

David M. Burner; David P. Belesky

2008-01-01

86

Characterization of Epichloë coenophiala within the US: are all tall fescue endophytes created equal?  

PubMed Central

Tall fescue (Lolium arundinaceum) is a valuable and broadly adapted forage grass that occupies approximately 14 million hectares across the United States. A native to Europe, tall fescue was likely introduced into the US around the late 1800's. Much of the success of tall fescue can be attributed to Epichloë coenophiala (formerly Neotyphodium coenophialum) a seed borne symbiont that aids in host persistence. Epichloë species are capable of producing a range of alkaloids (ergot alkaloids, indole-diterpenes, lolines, and peramine) that provide protection to the plant host from herbivory. Unfortunately, most tall fescue within the US, commonly referred to as “Kentucky-31” (KY31), harbors the endophyte E. coenophiala that causes toxicity to grazing livestock due to the production of ergot alkaloids. Molecular analyses of tall fescue endophytes have identified four independent associations, representing tall fescue with E. coenophiala, Epichloë sp. FaTG-2, Epichloë sp. FaTG-3, or Epichloë sp. FaTG-4. Each of these Epichloë species can be further distinguished based on genetic variation that equates to differences in the alkaloid gene loci. Tall fescue samples were evaluated using markers to simple sequence repeats (SSRs) and alkaloid biosynthesis genes to determine endophyte strain variation present within continental US. Samples represented seed and tillers from the Suiter farm (Menifee County, KY), which is considered the originating site of KY31, as well as plant samples collected from 14 states, breeder's seed and plant introduction lines (National Plant Germplasm System, NPGS). This study revealed two prominent E. coenophiala genotypes based on presence of alkaloid biosynthesis genes and SSR markers and provides insight into endophyte variation within continental US across historical and current tall fescue samples.

Young, Carolyn A.; Charlton, Nikki D.; Takach, Johanna E.; Swoboda, Ginger A.; Trammell, Michael A.; Huhman, David V.; Hopkins, Andrew A.

2014-01-01

87

Nano Scavenger Hunt  

NSDL National Science Digital Library

This is an activity (located on page 3 of PDF) about identifying nanoscale objects and phenomena in today's world. Learners will break into groups and conduct a "NanoBlitz Challenge," spending a set amount of time on a scavenger hunt for all things nano, both natural and man-made, in the world around them. They will then assemble a chart of their findings and discuss. Also relates to linked video, DragonflyTV Nano: Where's Nano?

Twin Cities Public Television, Inc.

2008-01-01

88

Greenhouse gas observations from Cabauw Tall Tower (1992-2010)  

NASA Astrophysics Data System (ADS)

Since 1992 semi-continuous in-situ observations of greenhouse gas concentrations have been performed at the tall tower of Cabauw (4.927° E, 51.971° N, -0.7 m a.s.l.). Through 1992 up to now, the measurement system has been gradually extended and improved in precision, starting with CO2 and CH4 concentrations from 200 m a.g.l. in 1992 to vertical gradients at 4 levels of the gases CO2, CH4, SF6, N2O, H2, CO and gradients at 2 levels for 222Rn. In this paper the measurement systems and measurement results are described for the main greenhouse gases and CO, for the whole period. The automatic measurement system now provides half-hourly concentration gradients with a precision better than or close to the WMO recommendations. The observations at Cabauw show a complex pattern caused by the influence of sources and sinks from a large area around the tower with significant contributions of sources and sinks at distances up to 500-700 km. The concentration footprint area of Cabauw is one the most intensive and complex source areas of greenhouse gases in the world. Despite this, annual mean trends for the most important greenhouse gases, compatible with the values derived using the global network, can be reproduced from the measured concentrations at Cabauw over the entire measurement period, with a measured increase in the period 2000-2009 for CO2 of 1.90 ± 0.1 ppm yr-1, for CH4 of 4.4 ± 0.6 ppb yr-1, for N2O of 0.86 ± 0.04 ppb yr-1, and for SF6 of 0.27 ± 0.01 ppt yr-1; for CO no significant trend could be detected. The influences of strong local sources and sinks are reflected in the amplitude of the mean seasonal cycles observed at Cabauw, that are larger than the mean Northern Hemisphere average; Cabauw mean seasonal amplitude for CO2 is 25-30 ppm (higher value for lower sampling levels). The observed CH4 seasonal amplitude is 50-110 ppb. All gases except N2O show highest concentrations in winter and lower concentrations in summer, N2O observations show two additional concentration maxima in early summer and in autumn. Seasonal cycles of the day-time mean concentrations show that surface concentrations or high elevation concentrations alone do not give a representative value for the boundary layer concentrations, especially in winter time, but that the vertical profile data along the mast can be used to construct a useful boundary layer mean value. The variability at Cabauw in the atmospheric concentrations of CO2 on time scales of minutes to hours is several ppm and is much larger than the precision of the measurements (0.1 ppm). The diurnal and synoptical variability of the concentrations at Cabauw carry information on the sources and sinks in the footprint area of the mast, that will be useful in combination with inverse atmospheric transport model to verify emission estimates and improve ecosystem models. For this purpose a network of tall tower stations like Cabauw forms a very useful addition to the existing global observing network for greenhouse gases.

Vermeulen, A. T.; Hensen, A.; Popa, M. E.; van den Bulk, W. C. M.; Jongejan, P. A. C.

2011-03-01

89

Greenhouse gas observations from Cabauw Tall Tower (1992-2010)  

NASA Astrophysics Data System (ADS)

Since 1992 semi-continuous in-situ observations of greenhouse gas concentrations have been performed at the tall tower of Cabauw (4.927° E, 51.971° N, -0.7 m a.s.l.). Through 1992 up to now, the measurement system has been gradually extended and improved in precision, starting with CO2 and CH4 concentrations from 200 m a.g.l. in 1992 to vertical gradients at 4 levels of the gases CO2, CH4, SF6, N2O, H2, CO and gradients at 2 levels for 222Rn. In this paper the measurement systems and measurement results are described for the main greenhouse gases and CO for the whole period. The automatic measurement system now provides half-hourly concentrations gradient with a precision better than or close to the WMO recommendations. The observations at Cabauw show a complex pattern caused by the influence of sources and sinks from a large area around the tower with significant contributions of sources and sinks at distances up to 500-700 km. The concentration footprint area of Cabauw is one the most intensive and complex source areas of greenhouse gases in the world. Despite this, annual mean trends for the most important greenhouse gases, compatible with the global values derived using the global network, can be reproduced from the measured concentrations at Cabauw over the entire measurement period, with a measured increase in the period 2000-2009 for CO2 of 1.90 ± 0.1 ppm yr-1, for CH4 of 4.4 ± 0.6 ppb yr-1, for N2O of 0.86 ± 0.04 ppb yr-1, and for SF6 of 0.27 ± 0.01 ppt yr-1; for CO no significant trend could be detected. The strong local sources and sinks reflect in the amplitude of mean seasonal cycles observed at Cabauw, that are larger than the mean Northern Hemisphere average; Cabauw mean seasonal amplitude for CO2 is 25-30 ppm (higher value for lower levels). CH4 seasonal amplitude observed is 50-110 ppb. All gases except N2O show highest concentrations in winter and lower concentrations in summer, N2O observations show two additional concentrations maxima in early summer and in autumn. Seasonal cycles of the day-time mean concentrations show that surface concentrations or high elevation concentrations alone do not give a representative value for the boundary layer concentrations, especially in winter time, but that the vertical profile data along the mast can be used to construct a useful boundary layer mean value. The variability at Cabauw in the atmospheric concentrations of CO2 on time scales of minutes to hours is several ppm and is much larger than the precision of the measurements (0.1 ppm). The diurnal and synoptical variability of the concentrations at Cabauw carry information on the sources and sinks in the footprint area of the mast, that is and will be used in combination with inverse atmospheric transport model to verify emission estimates and improve ecosystem models. For this purpose a network of tall tower stations like Cabauw is a very useful addition to the existing global observing network for greenhouse gases.

Vermeulen, A. T.; Hensen, A.; Popa, M. E.; van den Bulk, W. C. M.; Jongejan, P. A. C.

2010-09-01

90

Genotypic and chemotypic diversity of Neotyphodium endophytes in tall fescue from Greece.  

PubMed

Epichloid endophytes provide protection from a variety of biotic and abiotic stresses for cool-season grasses, including tall fescue. A collection of 85 tall fescue lines from 15 locations in Greece, including both Continental and Mediterranean germplasm, was screened for the presence of native endophytes. A total of 37 endophyte-infected lines from 10 locations were identified, and the endophytes were classified into five distinct groups (G1 to G5) based on physical characteristics such as colony morphology, growth rate, and conidial morphology. These classifications were supported by phylogenetic analyses of housekeeping genes tefA and tubB, and the endophytes were further categorized as Neotyphodium coenophialum isolates (G1, G4, and G5) or Neotyphodium sp. FaTG-2 (Festuca arundinacea taxonomic group 2 isolates (G2 and G3). Analyses of the tall fescue matK chloroplast genes indicated a population-wide, host-specific association between N. coenophialum and Continental tall fescue and between FaTG-2 and Mediterranean tall fescue that was also reflected by differences in colonization of host tillers by the native endophytes. Genotypic analyses of alkaloid gene loci combined with chemotypic (chemical phenotype) profiles provided insight into the genetic basis of chemotype diversity. Variation in alkaloid gene content, specifically the presence and absence of genes, and copy number of gene clusters explained the alkaloid diversity observed in the endophyte-infected tall fescue, with one exception. The results from this study provide insight into endophyte germplasm diversity present in living tall fescue populations. PMID:22660705

Takach, Johanna E; Mittal, Shipra; Swoboda, Ginger A; Bright, Sherrita K; Trammell, Michael A; Hopkins, Andrew A; Young, Carolyn A

2012-08-01

91

Genotypic and Chemotypic Diversity of Neotyphodium Endophytes in Tall Fescue from Greece  

PubMed Central

Epichloid endophytes provide protection from a variety of biotic and abiotic stresses for cool-season grasses, including tall fescue. A collection of 85 tall fescue lines from 15 locations in Greece, including both Continental and Mediterranean germplasm, was screened for the presence of native endophytes. A total of 37 endophyte-infected lines from 10 locations were identified, and the endophytes were classified into five distinct groups (G1 to G5) based on physical characteristics such as colony morphology, growth rate, and conidial morphology. These classifications were supported by phylogenetic analyses of housekeeping genes tefA and tubB, and the endophytes were further categorized as Neotyphodium coenophialum isolates (G1, G4, and G5) or Neotyphodium sp. FaTG-2 (Festuca arundinacea taxonomic group 2 isolates (G2 and G3). Analyses of the tall fescue matK chloroplast genes indicated a population-wide, host-specific association between N. coenophialum and Continental tall fescue and between FaTG-2 and Mediterranean tall fescue that was also reflected by differences in colonization of host tillers by the native endophytes. Genotypic analyses of alkaloid gene loci combined with chemotypic (chemical phenotype) profiles provided insight into the genetic basis of chemotype diversity. Variation in alkaloid gene content, specifically the presence and absence of genes, and copy number of gene clusters explained the alkaloid diversity observed in the endophyte-infected tall fescue, with one exception. The results from this study provide insight into endophyte germplasm diversity present in living tall fescue populations. PMID:22660705

Takach, Johanna E.; Mittal, Shipra; Swoboda, Ginger A.; Bright, Sherrita K.; Trammell, Michael A.; Hopkins, Andrew A.

2012-01-01

92

The effect of endophyte presence on Schedonorus arundinaceus (tall fescue) establishment varies with grassland community structure.  

PubMed

The endophyte Neotyphodium coenophialum in Schedonorus arundinaceus (tall fescue) may alter host interactions with specific resident species or shift the host's niche. These effects can be quantified by assessing tall fescue responses to, and effects on, the variation among resident species (selection) and resident species interactions (complementarity). To determine how N. coenophialum affects tall fescue, grassland microcosms containing 16 transplants of two, four, or eight resident species were seeded with endophyte-infected (E+) or endophyte-free (E-) Kentucky-31 (KY-31) tall fescue. All resident species were also grown in monoculture. Aboveground biomass was harvested 9 weeks after tall fescue was added (18 weeks' total growth). At harvest, more E+ than E- individuals were present and they represented a larger portion of the aboveground biomass across richness treatments, despite similar germination in concurrent trials. Tall fescue individuals were larger in microcosms dominated by more productive resident species (greater selection). In contrast, fewer E-, but not E+, individuals were present in microcosms with more facilitative interactions among the resident species (greater complementarity). E- and E+ tall fescue also affected resident species differently. High-richness E+ microcosms were more diverse and less dominated by productive species (lower selection) than E- microcosms. Thus, E+ KY-31 may more readily establish in, and affect, species-rich, functionally diverse communities as a result of niche shifts during establishment and negative effects on specific resident species. Although results need to be further tested under field conditions, it appears that endophyte presence may only facilitate KY-31 invasion into a limited suite of community types. PMID:24385086

Yurkonis, Kathryn A; Drystek, Emily; Maherali, Hafiz; Newman, Jonathan A

2014-04-01

93

Nano Research Facility Lab Safety Manual Nano Research Facility  

E-print Network

1 Nano Research Facility Lab Safety Manual Nano Research Facility: Weining Wang Office: Brauer rules and procedures (a) Accidents and spills for chemicals Not containing Nano-Materials Spills of non for chemicals Containing Nano-Materials In a fume hood small spills of nano-materials in a liquid may

Subramanian, Venkat

94

Integrated Micro Nano Systems Integrated Micro Nano Systems  

E-print Network

#12;Integrated Micro Nano Systems 2 #12;Integrated Micro Nano Systems 3 Val Jones (Ed.) Symposium on Integrated Micro Nano Systems: Convergence of bio and nanotechnologies, Enschede, The Netherlands, June 2006 Micro Nano Systems 4 #12;Integrated Micro Nano Systems 5 Preface In order to explore the convergence

Al Hanbali, Ahmad

95

Nano Fab Lab, Stockholm Sweden The Albanova Nano Fabrication Facility  

E-print Network

Nano Fab Lab, Stockholm Sweden The Albanova Nano Fabrication Facility Nano technology for basic research and small commercial enterprises Director: Prof. David Haviland #12;Nano Fab Lab, Stockholm Sweden Nano-Lab Philosophy · Nanometer scale patterning and metrology · Broad spectrum of user research

Haviland, David

96

High correlation between thermotolerance and photosystem II activity in tall fescue.  

PubMed

Heat stress affects a broad spectrum of cellular components and metabolism. The objectives of this study were to investigate the behavior of Photosystem II (PSII) in tall fescue (Festuca arundinacea Schreb) with various thermotolerance capacities and to broaden our comprehension about the relationship between thermotolerance and PSII function. Heat-tolerant and heat-sensitive accessions were incubated at 24 °C (control) and 46 °C (heat stress) for 5 h. The fluorescence transient curves (OJIP curves), slow Chl fluorescence kinetic, and light response curve were employed to study the behavior of PSII subjected to heat stress. After heat stress, performance index for energy conservation from photons absorbed by PSII antenna until the reduction of PSI acceptors (PITotal), the value of electrons produced per photon (a), and the maximal rate of electron transport (ETRmax) of heat-tolerant accessions were lower than those of heat-sensitive accessions. Relatively lower reactive oxygen species (ROS) contents were detected in heat-tolerant accessions. Simultaneously, there was a significant decline in the quantum yield of photochemical energy conversion in PS II (Y(II)), probability that a PSII Chl molecule functions as reaction center (?RC), and the increase of quantum yield for non-regulated non-photochemical energy loss (Y(NO)) in heat-tolerant accessions. Moreover, a significant inverse correlation between heat tolerance indexes (HTI) and Y(II) was observed. Therefore, maintaining a lower photochemical activity in heat-tolerant accessions could be a crucial strategy to improve their thermotolerance. This finding could be attributed to the structural difference in the reaction center, and for heat-tolerant accessions, it could simultaneously limit energy input into linear electron transport, and dissipate more energy through non-regulated non-photochemical energy loss processes. PMID:25145554

Chen, Ke; Sun, Xiaoyan; Amombo, Erick; Zhu, Qing; Zhao, Zhuangjun; Chen, Liang; Xu, Qingguo; Fu, Jinmin

2014-12-01

97

Diterpene resin acids: Major active principles in tall oil against Variegated cutworm,Peridroma saucia (Lepidoptera: Noctuidae).  

PubMed

Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45-60% compared to controls. This suppression was significantly (P?0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil. PMID:24249127

Xie, Y; Isman, M B; Feng, Y; Wong, A

1993-06-01

98

Aromatic hydrocarbon emissions in the United States deduced from tall tower measurements  

NASA Astrophysics Data System (ADS)

Aromatic compounds including benzene (C6H6), toluene (C7H8), and xylenes (C8H10) are important anthropogenic precursors of secondary organic aerosol and ground-level ozone. In addition, benzene has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). However, their emissions remain poorly constrained. Here we present a full year (2011) of continuous aromatic hydrocarbon measurements by PTR-MS at the University of Minnesota tall tower Tracer Gas Observatory (KCMP tall tower, 244 m a.g.l, 44.689°N, 93.073°W). We interpret the tall tower data with a 0.5° ×0.667° GEOS-Chem nested grid simulation to constrain US sources of benzene, toluene, and xylenes. The tall tower observations reveal a clear high bias in the model, with model: measurement slopes of 1.8, 5.3, and 2.9 for benzene, toluene, and xylenes, respectively. The high bias reflects an overestimate of aromatic hydrocarbon emissions in the model, which are based on the RETRO emission Inventory. In this work, we employ a Bayesian inversion to interpret the KCMP tall tower measurements in terms of quantitative constraints on US aromatic sources and the importance of sectors such as on-road transportation, waste treatment and disposal, solvent use, etc. We discuss our findings relative to other emission estimates (e.g., the EPA NEI) and in terms of their implications for air quality modeling.

Hu, L.; Millet, D. B.; Griffis, T. J.; Tessum, C.; Travis, K.

2013-12-01

99

Wood-derived olefins by steam cracking of hydrodeoxygenated tall oils.  

PubMed

Tall oil fractions obtained from Norwegian spruce pulping were hydrodeoxygenated (HDO) at pilot scale using a commercial NiMo hydrotreating catalyst. Comprehensive two dimensional gas chromatography (GC×GC) showed that HDO of both tall oil fatty acids (TOFA) and distilled tall oil (DTO) produced highly paraffinic hydrocarbon liquids. The hydrotreated fractions also contained fatty acid methyl esters and norabietane and norabietatriene isomers. Steam cracking of HDO-TOFA in a pilot plant revealed that high light olefin yields can be obtained, with 35.4 wt.% of ethene and 18.2 wt.% of propene at a coil outlet pressure (COP) of 1.7 bara, a dilution of 0.45 kg(steam)/kg(HDO-TOFA) and a coil outlet temperature (COT) of 820 °C. A pilot plant coking experiment indicated that cracking of HDO-TOFA at a COT of 850 °C results in limited fouling in the reactor. Co-cracking of HDO tall oil fractions with a typical fossil-based naphtha showed improved selectivity to desired light olefins, further demonstrating the potential of large scale olefin production from hydrotreated tall oil fractions in conventional crackers. PMID:23079410

Pyl, Steven P; Dijkmans, Thomas; Antonykutty, Jinto M; Reyniers, Marie-Françoise; Harlin, Ali; Van Geem, Kevin M; Marin, Guy B

2012-12-01

100

USC Nano Center Poster Session  

E-print Network

USC Nano Center Poster Session 19 April 2002 Nano-scale VLSI Design: A Significant Paradigm Shift The recent progression of events in nano-technology, from nanotubes to nano- transistors, begs a basic will the changes in underlying device materials theory of nano-scale electronics affect ways in which we currently

Davis, James P.

101

Strategies for mitigating wind-induced motion in tall buildings through aerodynamic and damping modifications  

E-print Network

The advent of modern structural systems, spurred by advances in construction methodology and high strength materials, has driven the height of modern skyscrapers beyond what was once deemed possible. Although science and ...

Nnamani, Nnabuihe

2012-01-01

102

On the contribution of mean flow and turbulence to city breathability: the case of long streets with tall buildings.  

PubMed

This paper analyses the contribution of mean flow and turbulence to city breathability within urban canopy layers under the hypothesis that winds from rural/marine areas are sources of clean air (inhale effect) and main contributors to local-scale pollutant dilution (exhale effect). Using Computational Fluid Dynamics (CFD) simulations, several idealized long streets flanked by tall buildings are investigated for wind flow parallel to the street axis. Aspect ratios (building height/street width) ranging from 2 to 4 and street lengths ranging from neighborhood scales (~1km in full scale) to city scales (~10km in full scale) are analyzed. To assess the inhale effect, the age of air concept is applied to quantify the time taken by a parcel of rural/marine air to reach a reference location within the urban canopy layer. To simulate the exhale effect, removal of pollutants released from a ground level source is considered. Numerical results agree with wind tunnel observations showing that a bulk portion of rural/marine air enters the streets through windward entries, a smaller part of it leaves through street roofs and the remaining fraction blows through the street aiding pollutant dilution. Substantial differences between neighborhood-scale and city-scale configurations are found. For neighborhood-scale models, pollutant removal by rural/marine air is mainly associated to mean flow along the streets. Breathability improves in streets flanked by taller buildings since in this case more rural/marine air is captured inside canyons leading to stronger wind along the street. For city-scale models, pollutant removal due to turbulent fluctuations across street roofs competes with that due to mean flows along the street. Breathability improves in streets flanked by lower buildings in which less rural/marine air is driven out and pollutant removal by turbulent fluctuations is more effective. Based on these findings, suggestions for ventilation strategies for urban areas with tall buildings are provided. PMID:22226399

Hang, Jian; Li, Yuguo; Buccolieri, Riccardo; Sandberg, Mats; Di Sabatino, Silvana

2012-02-01

103

Recent progress of seismic research on tall buildings in China Mainland  

NASA Astrophysics Data System (ADS)

As a result of rapid economic growth and urbanization in the past two decades, many tall buildings have been constructed in China Mainland, offering researchers and practitioners an excellent opportunity for research and practice in the field of structural engineering. This paper reviews progress by researchers throughout China Mainland on the seismic research of tall buildings, focusing on three major topics that impact the seismic performance of tall buildings. These are: (1) new types of steel-concrete composite structural members such as steel-concrete composite shear walls and columns, (2) earthquake resilient shear wall structures such as shear walls with replaceable structural components, self-centering shear walls and rocking walls, and (3) performance-based seismic design, including seismic performance index, performance level and design method. The paper concludes by presenting future research needs and directions in this field.

Lu, Xilin; Jiang, Huanjun

2014-08-01

104

caNanoLab  

Cancer.gov

Welcome to the cancer Nanotechnology Laboratory (caNanoLab) portal. caNanoLab is a data sharing portal designed to facilitate information sharing in the biomedical nanotechnology research community to expedite and validate the use of nanotechnology in biomedicine. caNanoLab provides support for the annotation of nanomaterials with characterizations resulting from physico-chemical and in vitro assays and the sharing of these characterizations and associated nanotechnology protocols in a secure fashion.

105

Comparison of Nitrogen Fixation Activity in Tall and Short Spartina alterniflora Salt Marsh Soils 1  

PubMed Central

A comparison of the N2 fixers in the tall Spartina alterniflora and short S. alterniflora marsh soils was investigated. Zero-order kinetics and first-order kinetics of acetylene reduction were used to describe the activity of the N2 fixers in marsh soil slurries. It was found that the Vmax values were approximately 10 times greater for the N2 fixers in the tall Spartina than in the short Spartina marsh when raffinose was used as the energy source. In addition, the (Ks + Sn) values were approximately 4 to 15 times lower for the N2 fixers in the tall Spartina than in short Spartina marsh. First-order kinetics of nitrogen fixation for several substrates indicate that the N2 fixers in the tall Spartina marsh were two to seven times more active than those in the short Spartina marsh. Ammonium chloride (25 ?g/ml) did not inhibit nitrogen fixation in the tall Spartina marsh, but there was a 50% inhibition in nitrogen fixation in the short Spartina marsh. On the other hand, sodium nitrate inhibited nitrogen fixation almost 100% at 25 ?g/ml in both soil environments. Amino nitrogen (25 to 100 ?g/ml) had little or no effect on nitrogen fixation. The results indicate that the N2 fixers in the tall Spartina marsh were physiologically more responsive to nutrient addition than those in the short Spartina marsh. This difference in the two populations may be related to the difference in daily tidal influence in the respective areas and thus provide another explanation for the enhanced S. alterniflora production in the creek bank soil system. PMID:16345213

Hanson, Roger B.

1977-01-01

106

Does fungal endophyte infection improve tall fescue's growth response to fire and water limitation?  

PubMed

Invasive species may owe some of their success in competing and co-existing with native species to microbial symbioses they are capable of forming. Tall fescue is a cool-season, non-native, invasive grass capable of co-existing with native warm-season grasses in North American grasslands that frequently experience fire, drought, and cold winters, conditions to which the native species should be better-adapted than tall fescue. We hypothesized that tall fescue's ability to form a symbiosis with Neotyphodium coenophialum, an aboveground fungal endophyte, may enhance its environmental stress tolerance and persistence in these environments. We used a greenhouse experiment to examine the effects of endophyte infection (E+ vs. E-), prescribed fire (1 burn vs. 2 burn vs. unburned control), and watering regime (dry vs. wet) on tall fescue growth. We assessed treatment effects for growth rates and the following response variables: total tiller length, number of tillers recruited during the experiment, number of reproductive tillers, tiller biomass, root biomass, and total biomass. Water regime significantly affected all response variables, with less growth and lower growth rates observed under the dry water regime compared to the wet. The burn treatments significantly affected total tiller length, number of reproductive tillers, total tiller biomass, and total biomass, but treatment differences were not consistent across parameters. Overall, fire seemed to enhance growth. Endophyte status significantly affected total tiller length and tiller biomass, but the effect was opposite what we predicted (E->E+). The results from our experiment indicated that tall fescue was relatively tolerant of fire, even when combined with dry conditions, and that the fungal endophyte symbiosis was not important in governing this ecological ability. The persistence of tall fescue in native grassland ecosystems may be linked to other endophyte-conferred abilities not measured here (e.g., herbivory release) or may not be related to this plant-microbial symbiosis. PMID:24497994

Hall, Sarah L; McCulley, Rebecca L; Barney, Robert J; Phillips, Timothy D

2014-01-01

107

Does Fungal Endophyte Infection Improve Tall Fescue's Growth Response to Fire and Water Limitation?  

PubMed Central

Invasive species may owe some of their success in competing and co-existing with native species to microbial symbioses they are capable of forming. Tall fescue is a cool-season, non-native, invasive grass capable of co-existing with native warm-season grasses in North American grasslands that frequently experience fire, drought, and cold winters, conditions to which the native species should be better-adapted than tall fescue. We hypothesized that tall fescue’s ability to form a symbiosis with Neotyphodium coenophialum, an aboveground fungal endophyte, may enhance its environmental stress tolerance and persistence in these environments. We used a greenhouse experiment to examine the effects of endophyte infection (E+ vs. E?), prescribed fire (1 burn vs. 2 burn vs. unburned control), and watering regime (dry vs. wet) on tall fescue growth. We assessed treatment effects for growth rates and the following response variables: total tiller length, number of tillers recruited during the experiment, number of reproductive tillers, tiller biomass, root biomass, and total biomass. Water regime significantly affected all response variables, with less growth and lower growth rates observed under the dry water regime compared to the wet. The burn treatments significantly affected total tiller length, number of reproductive tillers, total tiller biomass, and total biomass, but treatment differences were not consistent across parameters. Overall, fire seemed to enhance growth. Endophyte status significantly affected total tiller length and tiller biomass, but the effect was opposite what we predicted (E?>E+). The results from our experiment indicated that tall fescue was relatively tolerant of fire, even when combined with dry conditions, and that the fungal endophyte symbiosis was not important in governing this ecological ability. The persistence of tall fescue in native grassland ecosystems may be linked to other endophyte-conferred abilities not measured here (e.g., herbivory release) or may not be related to this plant-microbial symbiosis. PMID:24497994

Hall, Sarah L.; McCulley, Rebecca L.; Barney, Robert J.; Phillips, Timothy D.

2014-01-01

108

Comparison of Nitrogen Fixation Activity in Tall and Short Spartina alterniflora Salt Marsh Soils.  

PubMed

A comparison of the N(2) fixers in the tall Spartina alterniflora and short S. alterniflora marsh soils was investigated. Zero-order kinetics and first-order kinetics of acetylene reduction were used to describe the activity of the N(2) fixers in marsh soil slurries. It was found that the V(max) values were approximately 10 times greater for the N(2) fixers in the tall Spartina than in the short Spartina marsh when raffinose was used as the energy source. In addition, the (K(s) + S(n)) values were approximately 4 to 15 times lower for the N(2) fixers in the tall Spartina than in short Spartina marsh. First-order kinetics of nitrogen fixation for several substrates indicate that the N(2) fixers in the tall Spartina marsh were two to seven times more active than those in the short Spartina marsh. Ammonium chloride (25 mug/ml) did not inhibit nitrogen fixation in the tall Spartina marsh, but there was a 50% inhibition in nitrogen fixation in the short Spartina marsh. On the other hand, sodium nitrate inhibited nitrogen fixation almost 100% at 25 mug/ml in both soil environments. Amino nitrogen (25 to 100 mug/ml) had little or no effect on nitrogen fixation. The results indicate that the N(2) fixers in the tall Spartina marsh were physiologically more responsive to nutrient addition than those in the short Spartina marsh. This difference in the two populations may be related to the difference in daily tidal influence in the respective areas and thus provide another explanation for the enhanced S. alterniflora production in the creek bank soil system. PMID:16345213

Hanson, R B

1977-03-01

109

Integrating bermudagrass into tall fescue-based pasture systems for stocker cattle.  

PubMed

The daily BW gain of stocker steers grazing tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbysh. = Schedonorus arundinaceus (Schreb.) Dumort.]-based pastures typically declines during summer. To avoid these declines, in part to mitigate the effects of tall fescue toxicosis, it is commonly advised to move cattle to warm-season forage during this period. A 3-yr (2006, 2007, and 2008) grazing study was conducted to evaluate the effect of replacing 25% of the area of a tall fescue/clover (81% endophyte-infected) pasture system with "Ozark" bermudagrass [Cynodon dactylon (L.) Pers.] overseeded with clover (Trifolium spp.) to provide summer grazing for stocker steers (TF+BERM). The TF+BERM treatment was compared with a grazing system in which tall fescue/clover (TF) pastures were the only type of forage available for grazing. Our objective was to determine if replacement of 25% of the land area in a fescue system with bermudagrass would increase annual beef production compared with a system based solely on tall fescue. The study was conducted at the Southwest Research and Education Center of the University of Missouri near Mt. Vernon. Each treatment was rotationally stocked with 5 steers (248 ± 19.3 kg) on 1.7 ha. Fertilizer applications were applied at rates recommended for each respective forage species. Total forage production, BW gain per hectare, and season-long ADG of steers was greater (P < 0.06) for TF+BERM than for TF in 2006, but none of these measures differed (P > 0.19) in 2007 or 2008. In vitro true digestibility of pastures was greater (P = 0.01) for TF (84.4%, SEM = 0.64%) compared with TF+BERM (80.6%, SEM = 0.79%), even in summer. The decreased in vitro true digestibility of the bermudagrass pastures likely negated any benefit that animals in TF+BERM had in avoiding the ergot-like alkaloids associated with endophyte-infected tall fescue. Renovating 25% of the pasture system to bermudagrass provided some benefit to the system in years when summertime precipitation was limited (2006) but provided no value in wetter years (2007 and 2008). Although renovating endophyte-infected tall fescue pastures to a warm-season forage is a widely used practice to mitigate tall fescue toxicosis, the benefits of this practice are limited if forage quality of the warm season component is poor. PMID:21856893

Kallenbach, R L; Crawford, R J; Massie, M D; Kerley, M S; Bailey, N J

2012-01-01

110

Optimum testing intervals of building emergency power supply systems in tall buildings in the Hong Kong Special Administrative Region  

Microsoft Academic Search

The main objective of this study is to develop a model for the determination of optimum testing interval (OTI) of non-redundant standby plants. This study focuses on the emergency power generators in tall buildings in Hong Kong. The model for the reliability, which is developed, is applicable to any non-duplicated standby plant. In a tall building, the mobilisation of occupants

Yu Fat Kwok

1999-01-01

111

We all know that the Earth has tall mountains, but compared to its size these are actually very  

E-print Network

How Tall is ? We all know that the Earth has tall mountains, but compared to its size these are actually very small. If we were to shrink the Earth down to the size of a basketball, the tallest mountain of the Earth is actually larger at the equator than at the poles by about 0.3%. That's not much, but the Earth

112

Effect of nitrogen addition and drought on above-ground biomass of expanding tall grasses Calamagrostis epigejos and Arrhenatherum elatius  

Microsoft Academic Search

Tall expansive grasses act as serious weeds since they spread intensively and are a important threat to biodiversity of various\\u000a plant communities. A field experiment was set up based on three sets of paired plots, where Calamagrostis epigejos and Arrhenatherum elatius dominated and a mixture of both these tall grasses occurred. Parallel plots were treated by additional amounts of nitrogen

Karel Fiala; Ivan T?ma; Petr Holub

2011-01-01

113

Spine Shape in Sagittal and Frontal Planes in Short- and Tall-Statured Children Aged 13 Years  

ERIC Educational Resources Information Center

Study aim: To assess spine curvatures, postural categories and scolioses in short and tall children aged 13 years. Material and methods: Short-statured (below Percentile 10) and tall-statured (above Percentile 90) boys (n = 13 and 18, respectively) and girls (n = 10 and 11, respectively) aged 13 years were studied. The following angles of spine…

Lichota, Malgorzata

2008-01-01

114

46 CFR 34.20-90 - Installations contracted for prior to January 1, 1970-T/ALL.  

Code of Federal Regulations, 2012 CFR

...false Installations contracted for prior to January 1, 1970-T/ALL. 34.20-90 Section 34.20-90 Shipping COAST...20-90 Installations contracted for prior to January 1, 1970—T/ALL. (a) Installations contracted for prior to...

2012-10-01

115

46 CFR 32.40-65 - Crew accommodations on tankships constructed before June 15, 1987-T/ALL.  

Code of Federal Regulations, 2013 CFR

...accommodations on tankships constructed before June 15, 1987-T/ALL. 32.40-65 Section 32.40-65 Shipping COAST...accommodations on tankships constructed before June 15, 1987—T/ALL. All tankships of 100 gross tons and over...

2013-10-01

116

46 CFR 34.15-90 - Installations contracted for prior to January 1, 1962-T/ALL.  

Code of Federal Regulations, 2012 CFR

...false Installations contracted for prior to January 1, 1962-T/ALL. 34.15-90 Section 34.15-90 Shipping COAST...15-90 Installations contracted for prior to January 1, 1962—T/ALL. (a) Installations contracted for prior to...

2012-10-01

117

46 CFR 34.20-90 - Installations contracted for prior to January 1, 1970-T/ALL.  

Code of Federal Regulations, 2010 CFR

...false Installations contracted for prior to January 1, 1970-T/ALL. 34.20-90 Section 34.20-90 Shipping COAST...20-90 Installations contracted for prior to January 1, 1970—T/ALL. (a) Installations contracted for prior to...

2010-10-01

118

46 CFR 34.10-90 - Installations contracted for prior to May 26, 1965-T/ALL.  

Code of Federal Regulations, 2012 CFR

... false Installations contracted for prior to May 26, 1965-T/ALL. 34.10-90 Section 34.10-90 Shipping COAST...10-90 Installations contracted for prior to May 26, 1965—T/ALL. (a) Installations contracted for prior to...

2012-10-01

119

46 CFR 34.17-90 - Installations contracted for prior to January 1, 1962-T/ALL.  

Code of Federal Regulations, 2010 CFR

...false Installations contracted for prior to January 1, 1962-T/ALL. 34.17-90 Section 34.17-90 Shipping COAST...17-90 Installations contracted for prior to January 1, 1962—T/ALL. (a) Installations contracted for prior to...

2010-10-01

120

46 CFR 34.10-90 - Installations contracted for prior to May 26, 1965-T/ALL.  

Code of Federal Regulations, 2011 CFR

... false Installations contracted for prior to May 26, 1965-T/ALL. 34.10-90 Section 34.10-90 Shipping COAST...10-90 Installations contracted for prior to May 26, 1965—T/ALL. (a) Installations contracted for prior to...

2011-10-01

121

46 CFR 34.10-90 - Installations contracted for prior to May 26, 1965-T/ALL.  

Code of Federal Regulations, 2013 CFR

... false Installations contracted for prior to May 26, 1965-T/ALL. 34.10-90 Section 34.10-90 Shipping COAST...10-90 Installations contracted for prior to May 26, 1965—T/ALL. (a) Installations contracted for prior to...

2013-10-01

122

Nano Hive Simulator  

NSDL National Science Digital Library

NanoHive-1 is a modular simulator used for modeling the physical world at a nanometer scale. The intended purpose of the simulator is to act as a tool for the study, experimentation, and development of nanotech entities. NanoHive-1 is a GPL/LGPL licensed open-source development - you can download and use it for free.

2012-10-25

123

Sustainable nano-catalysis  

EPA Science Inventory

A novel nano-catalyst system which bridges the homogenous and heterogeneous system is described that is cheaper, easily accessible (sustainable) and requires no need of catalyst filtration during the work-up. Because of its nano-size, i.e. high surface area, the contact between r...

124

Protecting the Stair Enclosure in Tall Buildings Impacted by Stack Effect  

Microsoft Academic Search

Stair pressurization systems are the most commonly utilized means for protecting exit stairwells in high-rise buildings from smoke in the event of fire. Stair pressurization systems are difficult to design for tall buildings due to the impact of stack effect on maintaining uniform pressures over the building's height, and creation of excessive door overpressures that may impact exiting is a

Michael J. Ferreira; John Cutonilli

125

Measuring Plant Diversity in the Tall Threetip Sagebrush Steppe: Influence of Previous Grazing Management Practices  

Microsoft Academic Search

In July 2000, a 490-ha wildfire burned a portion of a long-term grazing study that had been established in 1924 at the US Sheep Experiment Station north of Dubois, Idaho, USA. Earlier vegetation measurements in this tall threetip sagebrush ( Artemisia tripartita spp. tripartita) bunchgrass plant community documented significant changes in vegetation due to grazing and the timing of grazing

Steven S. Seefeldt; Scott D. McCoy

2003-01-01

126

TALL FESCUE RESPONSE AND SOIL PROPERTIES FOLLOWING SOIL AMENDMENT WITH TANNERY WASTES  

EPA Science Inventory

Field plots were established in 1978 and 1979 on a Willamette sil in western Oregon to evaluate the effects of chrome tannery wastes on tall fescue (Festuca arundinacea) and soil properties. Three rates of waste material were applied each year; N, Ca, Mg, Cu, Cr, Mn, and Zn in so...

127

Occupational asthma induced by tall oil in the rubber tyre industry.  

PubMed

A worker in the rubber tyre industry is described with occupational asthma from exposure to a solution of tall oil, a pine resin, confirmed by specific inhalation challenge. This supports studies of contact dermatitis which have suggested abietic and dehydroabietic acid oxidants to be the cause of colophony induced allergic reactions. PMID:1551039

Tarlo, S M

1992-01-01

128

The "Standing Tall" Project: Using Theatre To Address the Effects of 9/11.  

ERIC Educational Resources Information Center

Explains the "Standing Tall" project, which was a multi-faceted project focused on embracing the future through creative drama, movement, storytelling, and improvisation activities. Notes that students' original stories of their experiences on September 11 were developed into a one-act play. Describes how students worked under the facilitation of…

Ebert, Michelle

2002-01-01

129

Endophyte symbiosis with tall fescue: how strong are the impacts on communities and ecosystems?  

E-print Network

: Competition Herbivory Lolium arundinaceum MAXQ endophyte Neotyphodium coenophialum Predators Soil Trophc with tall fescue over the past 13 y. Lolium arundinaceum is the most abundant plant in the eastern USA.05.002 #12;been devoted to similar questions with perennial ryegrass (Lolium perenne), meadow fescue (L

Rudgers, Jennifer

130

Stochastic simulation of clonal growth in the tall goldenrod, Solidago altissima  

Microsoft Academic Search

As clonal plants grow they move through space. The movement patterns that result can be complex and difficult to interpret without the aid of models. We developed a stochastic simulation model of clonal growth in the tall goldenrod, Solidago altissima. Our model was calibrated with field data on the clonal expansion of both seedlings and established clones, and model assumptions

M. L. Cain; S. W. Pacala; J. A. Silander

1991-01-01

131

Application of Body Mass Index According to Height-Age in Short and Tall Children  

PubMed Central

Background In children with either delayed or accelerated growth, expressing the body mass index (BMI) to chronological age might lead to invalid body composition estimates. Reference to height-age has been suggested for such populations; however its validity has not been demonstrated. Methods Anthropometric data of healthy children were obtained from the German KiGGS survey. We selected three samples with different height distributions representing short stature (mean height SDS: -1.6), normal stature (height SDS: 0), and tall stature (height SDS: +1.6), and compared BMI-for-age and BMI-for-height-age between these samples across the paediatric age range. Differences between samples were tested using Kruskal-Wallis one-way analysis of variance and permutation tests. Results At a given age, BMI was distributed towards lower values in short, and towards higher values in tall subjects as compared to a population with average height distribution. Expressing BMI to height-age eliminated these differences in boys with a short stature from 4 years to 14 years of age, in tall boys from 4 to 16 years, in short girls aged 2-10 years or tall girls aged 2-17 years. Conclusion From late infancy to adolescent age, BMI distribution co-varies with height distribution and referencing to height-age appears appropriate within this age period. However, caution is needed when data about pubertal status are absent. PMID:23951283

Bonthuis, Marjolein; Jager, Kitty J.; Abu-Hanna, Ameen; Verrina, Enrico; Schaefer, Franz; van Stralen, Karlijn J.

2013-01-01

132

Seismic Intensity Estimation of Tall Buildings in Earthquake Early Warning System  

E-print Network

Seismic Intensity Estimation of Tall Buildings in Earthquake Early Warning System M. H. Cheng & T. W. Graves U.S. Geological Survey, USA SUMMARY: In California, United States, an earthquake early; since the system broadcasts the location and time of the earthquake, user software can estimate

Greer, Julia R.

133

Initial stage in lightning initiated from tall objects and in rocket-triggered lightning  

E-print Network

Initial stage in lightning initiated from tall objects and in rocket- triggered lightning M. Miki,1 (160 m, Germany), and the Fukui chimney (200 m, Japan) and their counterparts in rocket. For rocket-triggered lightning the geometric mean (GM) values of the three overall characteristics

Florida, University of

134

Comparison of neural network and binary logistic regression methods in conceptual design of tall steel buildings  

Microsoft Academic Search

Purpose – To investigate the feasibility of using artificial neural networks for conceptual design of bracings systems for tall steel buildings. Design\\/methodology\\/approach – Database of 234 design examples has been developed using commercially available detailed design software. These examples represent building up to 20 storeys. Feed forward back-propagation neural network is trained on these examples. The results obtained from the

Hassan Al Nageim; Ravindra Nagar; Paulo J. G. Lisboa

2007-01-01

135

Acclimatization of soil respiration to warming in a tall grass prairie  

E-print Network

warming. Indeed, a coupled climate±carbon cycle model by Cox et al. (ref. 2) predicts 8.0 8C of global the interaction of global warming and land-use change. Experimental warming, on average, increased the daily mean respiration to warming in a tall grass prairie Yiqi Luo, Shiqiang Wan, Dafeng Hui & Linda L. Wallace

136

Effects of dairy slurry application on carabid beetles in tall fescue, British Columbia, Canada  

Microsoft Academic Search

Carabid populations were assessed in relation to type and level of nutrient input in a multi-year trial on tall fescue, Festuca arundinacea. Thirteen species of carabids were recovered, Pterostichus melanarius representing 81% of all catches. In 3m wide strip plots populations of P. melanarius increased with the rate of dairy slurry application, and the effect persisted for 2 years after

D. A Raworth; M. C Robertson; S Bittman

2004-01-01

137

Genetic Structure of Magnaporthe grisea Populations Associated with St. Augustinegrass and Tall Fescue in Georgia.  

PubMed

ABSTRACT Amplified fragment length polymorphisms (AFLPs) were used to estimate phylogenetic relationships within Magnaporthe grisea and determine the genetic structure of M. grisea populations associated with tall fescue and St. Augustinegrass in Georgia. Sixteen clonal lineages were identified in a sample population of 948 isolates. Five lineages were isolated from tall fescue (E, G1, G2, G4, and H), with lineage G4 comprising 90% of the population. Isolates from tall fescue were closely related to those from perennial ryegrass, weeping lovegrass, and wheat. Two M. grisea lineages were isolated from St. Augustinegrass (C and K), with lineage C comprising 99.8% of the population. Populations from crabgrass were dominated (98%) by lineage K, but also contained a single lineage C isolate. Haplotype diversity indices ranged from 0.00 to 0.29 in tall fescue populations and from 0.00 to 0.04 in St. Augustinegrass populations. Selection due to host species was the primary factor determining population structure according to analysis of molecular variance; host cultivar and geographical region had no significant effect. The host range of M. grisea lineages from turfgrasses was determined in growth chamber experiments and supports the prominent role of host species in determining the genetic structure of M. grisea populations from turfgrasses in Georgia. PMID:18943310

Tredway, L P; Stevenson, K L; Burpee, L L

2005-05-01

138

Effect of foliar disease on the epiphytic yeast communities of creeping bentgrass and tall fescue.  

PubMed

The effect of mechanical wounding or foliar diseases caused by Sclerotinia homoeocarpa or Rhizoctonia solani on the epiphytic yeast communities on creeping bentgrass and tall fescue were determined by leaf washing and dilution plating. Total yeast communities on healthy bentgrass and tall fescue leaves ranged from 7.9 x 103 to 1.4 x 105 CFU.cm-2 and from 2.4 x 103 to 1.6 x 104 CFU.cm-2, respectively. Mechanically wounded leaves (1 of 2 trials) and leaves with disease lesions (11 of 12 trials) supported significantly larger communities of phylloplane yeasts. Total yeast communities on S. homoeocarpa infected or R. solani infected bentgrass leaves were 3.6-10.2 times and 6.2-6.4 times larger, respectively, than the communities on healthy leaves. In general, healthy and diseased bentgrass leaves supported larger yeast communities than healthy or diseased tall fescue leaves. We categorized the majority of yeasts as white-pigmented species, including Cryptococcus laurentii, Cryptococcus flavus, Pseudozyma antarctica, Pseudozyma aphidis, and Pseudozyma parantarctica. The percentage of pink yeasts in the total yeast community ranged from 2.6% to 9.9% on healthy leaves and increased to 32.0%-44.7% on S. homoeocarpa infected leaves. Pink-pigmented yeasts included Rhodotorula glutinis, Rhodotorula mucilaginosa, Sakaguchia dacryoidea, and Sporidiobolus pararoseus. Foliar disease significantly affected community size and composition of epiphytic yeasts on bentgrass and tall fescue. PMID:15644900

Allen, Tom W; Quayyum, Habib A; Burpee, Leon L; Buck, James W

2004-10-01

139

IMPACT OF A LARGE SAN ANDREAS FAULT EARTHQUAKE ON TALL BUILDINGS IN SOUTHERN CALIFORNIA  

E-print Network

IMPACT OF A LARGE SAN ANDREAS FAULT EARTHQUAKE ON TALL BUILDINGS IN SOUTHERN CALIFORNIA Swaminathan the regional economy. Introduction The risk of earthquakes in southern California arises from two sources moderate earthquakes (moment magnitude 7). Fortunately, the urban areas of southern California have thus

Krishnan, Swaminathan

140

VIEW NORTHLEFTBUILDING 61 CARPENTER SHOP (1911) CENTERBUILDING 43ROPE WAREHOUSE (TALL ...  

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

VIEW NORTH-LEFT-BUILDING 61 CARPENTER SHOP (1911) CENTER-BUILDING 43-ROPE WAREHOUSE (TALL BUILDING) (1941) RIGHT-BUILDING 77-HEMP STORAGE (1920) - John A. Roebling's Sons Company & American Steel & Wire Company, South Broad, Clark, Elmer, Mott & Hudson Streets, Trenton, Mercer County, NJ

141

Current and electromagnetic field associated with lightning-return strokes to tall towers  

Microsoft Academic Search

An analysis of electric and magnetic fields radiated by lightning first and subsequent return strokes to tall towers is presented. The contributions of the various components of the fields, namely, static, induction, and radiation for the electric field, and induction and radiation for the magnetic field are illustrated and discussed. It is shown in particular that the presence of a

Farhad Rachidi; Wasyl Janischewskyj; Ali M. Hussein; Carlo Alberto Nucci; Silvia Guerrieri; Behzad Kordi; Jen-Shih Chang

2001-01-01

142

TITLE: Effects of Drought on the Performance of Two Hybrid Bluegrasses, Kentucky Bluegrass and Tall Fescue  

E-print Network

36 TITLE: Effects of Drought on the Performance of Two Hybrid Bluegrasses, Kentucky Bluegrass and Tall Fescue OBJECTIVE: Evaluate the effects of drought on the visual quality and photosynthesis in two, Kansas Turfgrass Foundation INTRODUCTION: Drought stress is a major problem in cool-season turfgrasses

143

Malate, Citrate, and Amino Acids in Tall Fescue Cultivars: Relationship to Animal Preference  

Microsoft Academic Search

cues when selecting forage diets. This study determined malate, citrate, and their total concentration is related to maturity and and amino acid concentrations in endophyte-free tall fescue (Festuca arundinacea Schreb.) and related those concentrations to cultivar, N nutrition of the plant (Yeoh and Watson, 1988). Bo- harvest time, and grazing-animal preference. 'Barcel', 'Kenhy', 'Ken- land et al. (1977) found large

Henry F. Mayland; Scott A. Martin; Julian Lee; Glenn E. Shewmaker

144

Modelization and Simulation of Nano Devices in nano calculus  

E-print Network

Modelization and Simulation of Nano Devices in nano calculus A. Credi1 , M. Garavelli1 , C. Laneve2, Paris Abstract. We develop a process calculus ­ the nano calculus ­ for modeling, analyzing and predicting the properties of molecular devices. The nano calculus is equipped with a simple stochastic model

Paris-Sud XI, Université de

145

Long term sequelae of sex steroid treatment in the management of constitutionally tall stature.  

PubMed Central

AIM--To evaluate possible long term side effects of high doses of sex steroids in the management of constitutionally tall stature, with special attention to hypothalamic-gonadal function. METHODS--Sixty four tall adult men and 180 tall adult women, who received supraphysiological doses of sex hormones during puberty, were interviewed in a standardised way at a mean follow up period of 10 years after cessation of treatment. Sixty one untreated tall adult men and 94 untreated tall adult women served as controls. RESULTS--The majority of the subjects were satisfied with their decision regarding hormone treatment. Seventy seven per cent of the women and 78% of the men reported one or more side effects during treatment. Most side effects were mild. In women, only 3% stopped treatment because of an adverse event; in men, the reported side effects never stopped treatment. The frequency of reported side effects in women was higher during treatment with high doses of oestrogens than during oral contraceptive use, indicating a dose dependent relationship. Amenorrhoea of longer than six months after cessation of therapy was found in 5%. Menstrual cycle characteristics of previously treated women were comparable with controls. Malignancy was not reported. Information about a total of 127 pregnancies was obtained and revealed no distinct differences in details and outcome between previously treated women and men, and controls. CONCLUSIONS--At a mean follow up of 10 years there is no evidence that pharmacological doses of sex hormones have a long term effect on reproductive function. However, this period is still too short to draw definite conclusions. PMID:7492194

de Waal, W J; Torn, M; de Muinck Keizer-Schrama, S M; Aarsen, R S; Drop, S L

1995-01-01

146

Sound of nano  

NASA Astrophysics Data System (ADS)

Ultrasound is widely used for imaging, measurement and diagnostics in the MHz region and is perhaps most familiar as a medical or non-destructive imaging or measurement tool. In the MHz frequency range the wavelength is typically measured in microns and is many times longer than the wavelength of visible light, limiting its resolution to objects much larger than the nano-scale. It is possible to perform ultrasonic imaging and measurement at much higher frequencies, in the GHz region. Here the acoustic wavelength is typically less than that of light permitting the higher resolutions than optical microscopy and the ability to probe micro and nano-scale objects. At these high frequencies ultrasonics has much to offer the nano-world as a powerful diagnostic tool: it could be used in circumstances where optical microscopy, electron microscopy and probe microscopy cannot, such as inside living objects. Despite the potential that ultrasonics offers for imaging and measurement at the micro and nano-scale, performing ultrasonics at the nano-scale is hampered by many problems that render the techniques typically used in the MHz region impractical. In this paper we discuss some of the practical problems standing in the way of nano-ultrasonics and some of the solutions, especially the use of pico-second laser ultrasonics and the development of nano-ultrasonic transducers and their application to ultrasonic imaging inside living cells.

Aylott, Jon; Clark, Matt; Marques, Leonel; Perez-Cota, Fernando; Smith, Richard J.; Webb, Kevin F.

2013-12-01

147

I en frsksserie med bde contortatall och tall i British Columbia ochYukon visar det sig att contortabastborren (mountain pine beetle) angriper svensk tall mer n contorta. Dremot var tallen vldigt lite angripen av contortans  

E-print Network

contortabastborren (mountain pine beetle) angriper svensk tall mer än contorta. Däremot var tallen väldigt lite gall rust förekom både på contorta och tall, men mest på con- torta. Foto:Anders Fries. · Mountain pine sanitetskontroller och man lyckades på så vis undvika att skadesvampar eller in- sekter följde med.Ganska snart

148

Comparative analysis of phytochrome-mediated growth responses in internodes of dwarf and tall pea plants  

Microsoft Academic Search

Responses of dark-grown pea seedlings of a dwarf (Progress No. 9) and a tall (Alaska) cultivar to red light have been compared 24 hours after irradiation. Identical percentage inhibition of elongation in 10-mm sub-apical segments of intact third internodes, identical dose-response curves and similar reversal of the inhibition by far-red light were observed. The time courses of the growth inhibition

D. W. Russell; A. W. Galston

1967-01-01

149

Comparative Criteria for Models of the Vascular Transport Systems of Tall Trees  

Microsoft Academic Search

\\u000a During the past decade, several detailed models of plant vascular transport systems (i.e. xylem and phloem) have been presented\\u000a in the literature, and many of them are currently capable of accurately modelling the hydraulic characteristics of trees,\\u000a including tall trees. This marks a departure from earlier modelling exercises in plant water relations, when models were intended\\u000a primarily to promote an

Maurizio Mencuccini; Teemu Hölttä; Jordi Martinez-Vilalta

150

Digestibility, apparent mineral absorption, and voluntary intake by horses fed alfalfa, tall fescue, and caucasian bluestem.  

PubMed

Alfalfa (Medicago sativa L.), low-endophyte (< 5%) tall fescue (Festuca arundinacea Schreb.), and caucasian bluestem (Bothriochloa caucasica [Trin.] C.E. Hubbard) were fed as chopped hay to six Arabian geldings (BW 441 kg; SE 2) in intake and digestibility experiments to determine nutritional value for horses at maintenance. Each experimental design was a replicated Latin square. Alfalfa was higher in DM and CP digestibility, IVDMD, apparent absorption of Ca, K, and S, and voluntary intake than the grasses (P < .05). Caucasian bluestem was higher in Zn but was lower in CP, TNC, Mg, P, K, S, and Cu concentrations than tall fescue. Crude protein digestibility and apparent absorption of Mg, K, and S were higher (P < .05) for tall fescue than for caucasian bluestem. Geldings fed alfalfa for ad libitum intake had higher serum concentrations of vitamin A, blood urea nitrogen, P, S, and Cu than geldings fed grass hays. Serum Zn was higher (P < .05), whole blood Se tended to be higher (P < .06), and BUN was lower (P < .05) in geldings fed caucasian bluestem than in those fed tall fescue. All forages met requirements for CP, Ca, Mg, K, and Fe when fed for ad libitum intake but were deficient in Cu for horses at maintenance. Caucasian bluestem was borderline in CP and was deficient in P but was the only forage that met the Zn requirement for the horses. Based on these results, caucasian bluestem could be a useful hay for horses but may require supplementation of CP and P. PMID:9250529

Crozier, J A; Allen, V G; Jack, N E; Fontenot, J P; Cochran, M A

1997-06-01

151

Tall shrub and tree expansion in Siberian tundra ecotones since the 1960s.  

PubMed

Circumpolar expansion of tall shrubs and trees into Arctic tundra is widely thought to be occurring as a result of recent climate warming, but little quantitative evidence exists for northern Siberia, which encompasses the world's largest forest-tundra ecotonal belt. We quantified changes in tall shrub and tree canopy cover in 11, widely distributed Siberian ecotonal landscapes by comparing very high-resolution photography from the Cold War-era 'Gambit' and 'Corona' satellite surveillance systems (1965-1969) with modern imagery. We also analyzed within-landscape patterns of vegetation change to evaluate the susceptibility of different landscape components to tall shrub and tree increase. The total cover of tall shrubs and trees increased in nine of 11 ecotones. In northwest Siberia, alder (Alnus) shrubland cover increased 5.3-25.9% in five ecotones. In Taymyr and Yakutia, larch (Larix) cover increased 3.0-6.7% within three ecotones, but declined 16.8% at a fourth ecotone due to thaw of ice-rich permafrost. In Chukotka, the total cover of alder and dwarf pine (Pinus) increased 6.1% within one ecotone and was little changed at a second ecotone. Within most landscapes, shrub and tree increase was linked to specific geomorphic settings, especially those with active disturbance regimes such as permafrost patterned-ground, floodplains, and colluvial hillslopes. Mean summer temperatures increased at most ecotones since the mid-1960s, but rates of shrub and tree canopy cover expansion were not strongly correlated with temperature trends and were better correlated with mean annual precipitation. We conclude that shrub and tree cover is increasing in tundra ecotones across most of northern Siberia, but rates of increase vary widely regionally and at the landscape scale. Our results indicate that extensive changes can occur within decades in moist, shrub-dominated ecotones, as in northwest Siberia, while changes are likely to occur much more slowly in the highly continental, larch-dominated ecotones of central and eastern Siberia. PMID:24115456

Frost, Gerald V; Epstein, Howard E

2014-04-01

152

Combined effects of folivory and neighbor plants on Cirsium altissimum (tall thistle) rosette performance  

Microsoft Academic Search

Predicting how herbivory and neighbor plant interactions combine to affect host plants is critical to explaining variation\\u000a in herbivores’ impact on plant population dynamics. In a field experiment, we asked whether the combined effects of neighbor\\u000a plants and folivores upon performance of tall thistle (Cirsium altissimum), a monocarpic perennial, can be predicted as the product of their individual effects (i.e.,

F. Leland Russell; Machale N. Spencer

2010-01-01

153

Genetic Transformation in Festuca arundinacea Schreb. (Tall Fescue) and Festuca pratensis Huds. (Meadow Fescue)  

Microsoft Academic Search

\\u000a Tall fescue (Festuca arundinacea Schreb.) is a wind-pollinated, highly self-infertile polyploid perennial cool-season forage, turf, and conservation grass.\\u000a It is indigenous to Europe, also naturally occuring on the Baltic coasts throughout the Caucasus, in western Siberia, and\\u000a extending into China. Introductions have been made into North and South America, Australia, New Zealand, Japan, and South\\u000a and East Asia (Barnes 1990).

G. Spangenberg; Z.-Y. Wang; M. P. Vallés; I. Potrykus

154

Greenhouse gases measurements at Zotino Tall Tower Observatory (ZOTTO) in central Siberia  

NASA Astrophysics Data System (ADS)

Boreal ecosystems play a crucial role in atmospheric carbon budget calculations as they represent about one third of the Earth's forested land surface area and are typically a net sink of carbon dioxide and a net source of methane. However, direct measurements of carbon dioxide, water vapor, and methane in large areas of the boreal zone, such as Central Siberia, are sparse and unevenly distributed in space. In order to improve the spatial coverage and representativeness of flux estimates and reduce their uncertainty, our group has begun eddy covariance measurements to complement our tall tower measurements in Central Siberia. The Zotino Tall Tower Observatory (ZOTTO, www.zottoproject.org) measurement site is located in pristine taiga near the Yenisei river (60°48'N, 89°21'E). The ZOTTO tall tower is equipped with continuous, low-maintenance CO2/CH4 concentration measurements by cavity ring down spectroscopy (CRDS) from six heights up to 301 m since May 2009. Additionally, we have set up two eddy covariance flux measurement systems in the forest and in the bog, located 1 and 3 km from the tall tower, respectively. Both towers are equipped with an enclosed CO2/H2O gas analyzer and ultrasonic anemometers. The bog tower includes a CH4 eddy covariance gas analyzer. Here, we report atmospheric CO2 and CH4 concentrations, focusing on growing season of 2012. The net ecosystem exchange (NEE) and evapotranspiration in boreal forest eddy site, and carbon fluxes in the wetland area (60°49'N, 89°23'E) are examined in terms of their relationship with major controlling factors such as temperature, photosynthetically active radiation, vapor pressure deficits, soil moisture, and friction velocity.

Park, Sung-Bin; Lavri?, Jošt V.; Kolle, Olaf; Vesala, Timo; Panov, Alexey; Heimann, Martin

2014-05-01

155

Critical analysis of height reduction in oestrogen-treated tall girls  

Microsoft Academic Search

Twenty-one girls with familial tall stature were reevaluated at 18 years of age. Fourteen of them had been treated with high-dose oestrogens (I), while seven girls had not been treated (II). The untreated group is comparable but not a strict control group. Recordings on initiation of the study were: Chronologic age: 12.0±1.4 (I) versus 13.5±1.5 years (II; x), Bone age:

W. Sorgo; K. Scholler; F. Heinze; E. Heinze; W. M. Teller

1984-01-01

156

46 CFR 34.25-90 - Installations contracted for prior to January 1, 1964-T/ALL.  

Code of Federal Regulations, 2010 CFR

...Section 34.25-90 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Water Spray Extinguishing Systems, Details § 34.25-90 Installations contracted for prior to January 1, 1964—T/ALL....

2010-10-01

157

A contribution to urbanism--the tall building as a multi-dimensional framework for additive growth and change  

E-print Network

Skyscrapers do not destroy cities; they make them look different and they make the urban space more crowded, but they have not yet put an end to the urban environment. Many of the problems with the early tall buildings ...

Nelson, David J. (David Jeffrey)

1987-01-01

158

Nitrogen isotope tracer acquisition in low and tall birch tundra plant communities: a 2 year test of the snowshrub  

E-print Network

cycling in low and tall shrub ecosystems that have the same species composition. Experimentally deep- ened of the deciduous shrubs alder, willow, and birch is a major component of this vegetation transition (Chapin et al

Grogan, Paul

159

Transgenic Expression of MsHsp23 Confers Enhanced Tolerance to Abiotic Stresses in Tall Fescue  

PubMed Central

Tall fescue (Festuca arundinacea Schreb.) is an important cool season forage plant that is not well suited to extreme heat, salts, or heavy metals. To develop transgenic tall fescue plants with enhanced tolerance to abiotic stress, we introduced an alfalfa Hsp23 gene expression vector construct through Agrobacterium-mediated transformation. Integration and expression of the transgene were confirmed by polymerase chain reaction, northern blot, and western blot analyses. Under normal growth conditions, there was no significant difference in the growth of the transgenic plants and the non-transgenic controls. However, when exposed to various stresses such as salt or arsenic, transgenic plants showed a significantly lower accumulation of hydrogen peroxide and thiobarbituric acid reactive substances than control plants. The reduced accumulation of thiobarbituric acid reactive substances indicates that the transgenic plants possessed a more efficient reactive oxygen species-scavenging system. We speculate that the high levels of MsHsp23 proteins in the transgenic plants protect leaves from oxidative damage through chaperon and antioxidant activities. These results suggest that MsHsp23 confers abiotic stress tolerance in transgenic tall fescue and may be useful in developing stress tolerance in other crops. PMID:25049632

Lee, Ki-Won; Choi, Gi Jun; Kim, Ki-Yong; Ji, Hee Jung; Park, Hyung Soo; Kim, Yong-Goo; Lee, Byung Hyun; Lee, Sang-Hoon

2012-01-01

160

Enhancement of phenanthrene and pyrene degradation in rhizosphere of tall fescue (Festuca arundinacea).  

PubMed

A greenhouse experiment was conducted with varying concentrations of phenanthrene (11-344 mg kg(-1)) and pyrene (15-335 mg kg(-1)) spiked in the soil to evaluate the phytoremediation of PAHs contaminated soil using tall fescue (Festuca arundinacea). After 65-day of tall fescue growth, plant biomass, microbial viable counts, dehydrogenase activity, water-soluble phenolic compounds, phenanthrene and pyrene residual concentrations and removal percentages were determined. The results showed that target PAHs (phenanthrene and pyrene) did not affect plant biomass at lower concentrations but a reduced biomass (only 53.5% of shoot and 29.7% of root compared to control) was observed at higher concentrations. Higher biological activities (microbial viable counts, water-soluble phenolic compounds, dehydrogenase activity) and PAHs degradation rates were detected in planted soils than unplanted controls. After harvest, 91.7-97.8% of phenanthrene and 70.8-90.0% of pyrene had been degraded in the planted soils, which were 1.88-3.19% and 8.85-20.69% larger than those in corresponding unplanted soils. This enhanced dissipation of target PAHs in planted soils might be derived from increased biological activity in the rhizosphere. The results of the present study suggest that the presence of tall fescue roots were effective in promoting the phytoremediation of PAHs contaminated soil. PMID:19150175

Cheema, Sardar Alam; Khan, Muhammad Imran; Tang, Xianjin; Zhang, Congkai; Shen, Chaofeng; Malik, Zaffar; Ali, Shafaqat; Yang, Jianjun; Shen, Kaili; Chen, Xincai; Chen, Yingxu

2009-07-30

161

Transgenic Expression of MsHsp23 Confers Enhanced Tolerance to Abiotic Stresses in Tall Fescue.  

PubMed

Tall fescue (Festuca arundinacea Schreb.) is an important cool season forage plant that is not well suited to extreme heat, salts, or heavy metals. To develop transgenic tall fescue plants with enhanced tolerance to abiotic stress, we introduced an alfalfa Hsp23 gene expression vector construct through Agrobacterium-mediated transformation. Integration and expression of the transgene were confirmed by polymerase chain reaction, northern blot, and western blot analyses. Under normal growth conditions, there was no significant difference in the growth of the transgenic plants and the non-transgenic controls. However, when exposed to various stresses such as salt or arsenic, transgenic plants showed a significantly lower accumulation of hydrogen peroxide and thiobarbituric acid reactive substances than control plants. The reduced accumulation of thiobarbituric acid reactive substances indicates that the transgenic plants possessed a more efficient reactive oxygen species-scavenging system. We speculate that the high levels of MsHsp23 proteins in the transgenic plants protect leaves from oxidative damage through chaperon and antioxidant activities. These results suggest that MsHsp23 confers abiotic stress tolerance in transgenic tall fescue and may be useful in developing stress tolerance in other crops. PMID:25049632

Lee, Ki-Won; Choi, Gi Jun; Kim, Ki-Yong; Ji, Hee Jung; Park, Hyung Soo; Kim, Yong-Goo; Lee, Byung Hyun; Lee, Sang-Hoon

2012-06-01

162

Tall fescue endophyte effects on tolerance to water-deficit stress  

PubMed Central

Background The endophytic fungus, Neotyphodium coenophialum, can enhance drought tolerance of its host grass, tall fescue. To investigate endophyte effects on plant responses to acute water deficit stress, we did comprehensive profiling of plant metabolite levels in both shoot and root tissues of genetically identical clone pairs of tall fescue with endophyte (E+) and without endophyte (E-) in response to direct water deficit stress. The E- clones were generated by treating E+?plants with fungicide and selectively propagating single tillers. In time course studies on the E+?and E- clones, water was withheld from 0 to 5 days, during which levels of free sugars, sugar alcohols, and amino acids were determined, as were levels of some major fungal metabolites. Results After 2–3 days of withholding water, survival and tillering of re-watered plants was significantly greater for E+?than E- clones. Within two to three days of withholding water, significant endophyte effects on metabolites manifested as higher levels of free glucose, fructose, trehalose, sugar alcohols, proline and glutamic acid in shoots and roots. The fungal metabolites, mannitol and loline alkaloids, also significantly increased with water deficit. Conclusions Our results suggest that symbiotic N. coenophialum aids in survival and recovery of tall fescue plants from water deficit, and acts in part by inducing rapid accumulation of these compatible solutes soon after imposition of stress. PMID:24015904

2013-01-01

163

Full-scale monitoring of typhoon effects on super tall buildings  

NASA Astrophysics Data System (ADS)

This paper presents the field measurement results of wind characteristics and structural responses of two super tall buildings, Central Plaza Tower (374 m, 78 floors) in Hong Kong and Di Wang Tower (384 m, 78 floors) in Shenzhen during the passage of Typhoon Sally. The field data such as wind speeds, wind directions and acceleration responses were simultaneously and continuously measured from the tall buildings during the typhoon. Detailed analysis of the field data and comparative study were conducted to investigate the characteristics of typhoon-generated wind over the two cities and wind-induced vibrations of the two super tall buildings under typhoon condition. The dynamic characteristics of the buildings were determined on the basis of the field measurements and comparisons with those calculated from the computational models of the buildings were made. The damping ratios of the buildings were estimated and the amplitude-dependent damping characteristics are presented and discussed. Furthermore, the full-scale measurements were compared with the wind tunnel results to evaluate the accuracy of the model test results and the adequacy of the techniques used in wind tunnel tests.

Li, Q. S.; Xiao, Y. Q.; Wong, C. K.

2005-07-01

164

Tall oil precursors in three western pines: ponderosa, lodgepole, and limber pine  

SciTech Connect

The nonvolatile diethyl ether extracts (NVEE) from ponderosa, lodgepole, and limber pines were analyzed to determine the amounts and chemical composition of the tall oil precursors (resin acids, fatty acids, and nonsaponifiables) and turpentine precursors available from these species. The results showed that crude tall oil compositions would be approximately as follows (% resin acids, % fatty acids, % nonsaponifiables); ponderosa pine - sapwood (15, 75, 10), heartwood (78, 7, 15); lodgepole pine - sapwood (24, 57, 19), heartwood (51, 26, 23); limber pine - sapwood (10, 82, 8), heartwood (23, 60, 17). The larger nonsaponifiables content, as compared to southern pines, is the major factor in explaining the greater difficulty in the distillative refining of tall oil from these western species. Eight resin acids were found in ponderosa and lodgepole pine: palustric, isopimaric, abietic, dehydroabietic, and neoabietic acids predominated. Seven resin acids were identified from limber pine: anticopalic, isopimaric, abietic, and dehydroabietic acids predominated. The free and esterfied fatty acids from these species contained predominantly oleic and linoleic acids. In addition limber pine contained major amounts of 5, 9, 12-octadecatrienoic acid. The nonsaponifiables contained mostly diterpenes and the sterols, sitosterol and campesterol. The major turpentine components were: ponderosa pine - ..beta..-pinene and 3-carene; lodgepole pine - ..beta..-phellandrene; and limber pine - 3-carene, ..beta..-phellandrene, ..cap alpha..-piene, and ..beta..-pinene.

Conner, A.H.; Diehl, M.A.; Rowe, J.W.

1980-01-01

165

MR imaging techniques for nano-pathophysiology and theranostics.  

PubMed

The advent of nanoparticle DDSs (drug delivery systems, nano-DDSs) is opening new pathways to understanding physiology and pathophysiology at the nanometer scale. A nano-DDS can be used to deliver higher local concentrations of drugs to a target region and magnify therapeutic effects. However, interstitial cells or fibrosis in intractable tumors, as occurs in pancreatic or scirrhous stomach cancer, tend to impede nanoparticle delivery. Thus, it is critical to optimize the type and size of nanoparticles to reach the target. High-resolution 3D imaging provides a means of "seeing" the nanoparticle distribution and therapeutic effects. We introduce the concept of "nano-pathophysiological imaging" as a strategy for theranostics. The strategy consists of selecting an appropriate nano-DDS and rapidly evaluating drug effects in vivo to guide the next round of therapy. In this article we classify nano-DDSs by component carrier materials and present an overview of the significance of nano-pathophysiological MRI. PMID:24787226

Bennett, Kevin M; Jo, Jun-ichiro; Cabral, Horacio; Bakalova, Rumiana; Aoki, Ichio

2014-07-30

166

Warming reduces tall fescue abundance but stimulates toxic alkaloid concentrations in transition zone pastures of the U.S.  

PubMed Central

Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte also produces alkaloids toxic to insects (e.g., lolines) and mammals (ergots; which can cause “fescue toxicosis” in grazing animals). The negative animal health and economic consequences of fescue toxicosis make understanding the response of the tall fescue symbiosis to climate change critical for the region. We experimentally increased temperature (+3°C) and growing season precipitation (+30% of the long-term mean) from 2009–2013 in a mixed species pasture, that included a tall fescue population that was 40% endophyte-infected. Warming reduced the relative abundance of tall fescue within the plant community, and additional precipitation did not ameliorate this effect. Warming did not alter the incidence of endophyte infection within the tall fescue population; however, warming significantly increased concentrations of ergot alkaloids (by 30–40%) in fall-harvested endophyte-infected individuals. Warming alone did not affect loline alkaloid concentrations, but when combined with additional precipitation, levels increased in fall-harvested material. Although future warming may reduce the dominance of tall fescue in eastern U.S. pastures and have limited effect on the incidence of endophyte infection, persisting endophyte-infected tall fescue will have higher concentrations of toxic alkaloids which may exacerbate fescue toxicosis. PMID:25374886

McCulley, Rebecca L.; Bush, Lowell P.; Carlisle, Anna E.; Ji, Huihua; Nelson, Jim A.

2014-01-01

167

Relative roles of different-sized herbivores and plant-plant interactions in tall shrub tundra vegetation  

NASA Astrophysics Data System (ADS)

Tall shrubs play important roles in the ecology of Arctic tundra ecosystems, including support of high shrub-associated biodiversity and regulation of a range of ecosystem processes. Tall shrub patches and herbaceous vegetation surrounding them often form a two-state vegetation mosaic. Such tall shrub tundra vegetation is an important locus for current vegetation changes in the Arctic. Both abiotic and biotic drivers are known to influence the shrub component. However, although expansion of the shrub state has received much focus lately, relative strengths of the multiple drivers of vegetation state are currently not fully understood. We investigated the role of herbivory relative to temperature and relative to plant-plant interactions, conducting a field survey and experimental studies at large spatial scales in riparian tall shrub tundra in Norway. We found both summer temperatures and summer grazing by reindeer (Rangifer tarandus) to affect tall shrub distribution and expansion potential. Furthermore, we found strong and rapid shrub growth change in response to abundance of key arctic herbivores; small rodents. Finally, we quantified the relative importance of neighboring plants and both herbivore types to recruiting tall shrubs. The previously unforeseen rate at which tall shrub tundra responded to altered herbivore pressures further exemplifies its central role in the tundra ecosystems, promoting tall shrub tundra as a bell-whether of change with respect to both abiotic and biotic drivers. While many of the results clearly relate to herbivory, neighboring plants or climate as drivers, some variation remains unexplained warranting future research focus on this highly dynamic part of the tundra ecosystem. Our results suggest that spatially variable biotic interactions are likely to modify forcing by climate, calling for an ecosystem approach when studying change in tundra ecosystems.

Ravolainen, Virve; Ims, Rolf; Bårdsen, Bård-Jørgen; Stien, Audun; Kollstrøm, Julie; Lægreid, Eiliv; Bråthen, Kari Anne

2013-04-01

168

What is Nano-Infusion?  

NSDL National Science Digital Library

This page from Nano-Link describes Nano-Infusion. This program "promotes integration and inclusion of nanoscale concepts into high school and college level education." Teachers are encouraged to join the free program to obtain training, support, and nano-related supplies that will aid in introducing nano experiments into their classrooms. To join the program, applicants merely need to create an account on the Nan-Link website and complete and introductory survey.

2012-11-08

169

The Nano Claw  

E-print Network

Contents 1 Executive Summary 3 2 Nano Claw Design and Operation 3 2.1 Design Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Operation Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3 SMA Technology in NanoClaw . . . . . . . . . . . . . . . . . . . . 5 2.3.1 The Shape Memory Eect . . . . . . . . . . . . . . . . . . . 5 2.3.2 Programming . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Applications 6 3.1 Blood Vessel Cleaner . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.2 Mask Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4 Conclusions 9 2 1 Executive Summary Do to the dramatically small scale of nanosystems, it is very hard to manipulate objects at this level. A tool that could grip and manipulate nanometer-sized objects would be very useful. The Nano Claw attempts to solve this problem and is constructed using a cul

unknown authors

170

'Lump Sugar and Salt Shaker'-Like Nano and Pico Space Devices and Robots  

NASA Astrophysics Data System (ADS)

Nano, Pico Space Devices and Robots (NPSDR) with a new strategy, multiple parallel use of these great number of devices allows the covering of larger surfaces on the planet measuring several focused parameters, e.g., DDS. Environmental friendly design.

Vizi, P.; Horváth, A.; Hudoba, Gy.; Bérczi, Sz.; Sík, A.

2012-10-01

171

Highly surfaced polypyrrole nano-networks and nano-fibers  

Microsoft Academic Search

Polypyrrole (PPy) nano-networks and nano-fibers were synthesized using interfacial and template polymerization techniques, respectively. The morphology of the PPy nano-networks showed that a homogeneous, three-dimensionally grown nano-fibers were produced. Dodecyl sulfonate was used as surfactant in the interfacial polymerization. Bulk conductivity of PPy nano-networks were in a range of 10?1–10?4 S\\/cm with a surface area of ca. 480 m2\\/g. Template synthesis produced one-directional

Muge Acik; Canan Baristiran; Gursel Sonmez

2006-01-01

172

TryNano.org  

NSDL National Science Digital Library

This is the portal for TryNano.org, a website for anyone interested in learning about nanoscience and nanotechnology. Users can explore nanomaterials, read about timely discoveries in the field, and learn about how scientists can manipulate objects on the scale of .4 to 10nm. Teachers will find seven standards-aligned lessons on nanotechnology -- 5 for middle school and 2 for high school. Students can play the NanoMission Game Series, Duckboy in Nanoland, and Virtual Microscope. Click on "Meet Professionals" to find out what nanotechnologists do. This collection is part of TryEngineering.org, a website maintained by the Institute of Electrical and Electronics Engineers (IEEE).

2011-12-05

173

An amperometric hydrogen peroxide biosensor based on immobilizing horseradish peroxidase to a nano-Au monolayer supported by sol–gel derived carbon ceramic electrode  

Microsoft Academic Search

A novel strategy for fabricating horseradish peroxidase (HRP)-based H2O2 sensor has been developed by combining the merits of carbon sol–gel supporting matrix and nano-scaled particulate gold (nano-Au) mediator. The thiol functional group-derived carbon ceramic electrode (CCE) was first constructed using (3-mercaptopropyl) trimethoxy silane as sol–gel monomer. Then, the stable nano-Au monolayer was obtained through covalent linkage between nano-Au and thiol

Cun-Xi Lei; Shun-Qin Hu; Na Gao; Guo-Li Shen; Ru-Qin Yu

2004-01-01

174

Influence of Nano Fillers in the Development of Glass Epoxy –Nano Alumina Hybrid Nano Composite  

E-print Network

The research is carried out to develop a new polymer matrix hybrid Nano composite. The effect of alumina Nano particles between the glass fibre and epoxy resin was investigated. Well-dispersed Nano particles enhanced significantly the mechanical strength between fibre and matrix. The experimental analysis demonstrated that the quality of fibre/matrix interface was improved after the addition of alumina Nano particles to glass fiber.

unknown authors

175

Construction of micro-nano network structure on titanium surface for improving bioactivity  

NASA Astrophysics Data System (ADS)

A novel hierarchical micro-nano structured titania layer was constructed on Ti surface to mimic the multi-level bone structure. The Ti substrate was subjected to a suitable acid etching and subsequent anodization in NaOH electrolyte to form a micro-nano porous titania layer. It was indicated that this microporous/nano-network (micro/nano-network) structured surface presented the enhanced wettability and superhydrophilic property. The polarization curve measurements showed that the as-prepared micro/nano-network structured TiO2 surface was of better corrosion resistance compared to the blank Ti surface, according to its corrosion current decreased, corrosion potential shifted positively and polarization resistance increased in Hank's solution. Meanwhile, the Mott-Schottky plots revealed that less oxygen vacancies existed in the micro/nano-network structured TiO2 film in contrast to the natural oxide film on blank Ti surface. Moreover, it was observed that the micro/nano-network structured surface was completely covered by a homogeneous apatite layer when immersed in simulated body fluid (SBF) for 14 days, exhibiting an excellent ability of biomineration. Furthermore, the superior cell adhesion and viability were discerned on such hierarchically structured surface, through a comparison of MG63 cell behaviors on blank Ti surface, nano-network structured surface and micro/nano-network structured surface. All results suggest our construction of micro-nano porous TiO2 surface is a promising strategy for improving the bioactivity of titanium implants.

Jiang, Pinliang; Liang, Jianhe; Lin, Changjian

2013-09-01

176

Building Tall  

NSDL National Science Digital Library

In this engineering activity (page 2 of PDF), young learners investigate how a wide base can make a building more stable. Learners use blocks or boxes of different sizes to construct stable towers. Learners will compare and contrast different structures, document their observations, experiment with different materials, and conduct stability tests. This activity is part of the Curious George "Under Construction" lesson plan and related to the show Curious George on PBS, specifically the episode "Curious George's Home for Pigeons." The lesson plan includes several activities that explore building engineering. Activities are connected to fiction and non-fiction books and include family extension projects.

Kids, Pbs

2006-01-01

177

Nano Ice Cream  

NSDL National Science Digital Library

In this activity/demo, learners discover how liquid nitrogen cools a creamy mixture at such a rapid rate that it precipitates super fine grained (nano) ice cream. This is a fun (and tasty!) way for learners to discover the nanoworld! Note: this activity should be conducted by adults only.

Network, Nanoscale I.; Science, Museum O.

2014-06-04

178

Short-term temporal dynamics of yeast abundance on the tall fescue phylloplane.  

PubMed

Six replicate trials were conducted to determine the short-term temporal dynamics and the effects of foliar applications of nutrients on the phylloplane yeast community of tall fescue (Festuca arundinacea Schreb.). In each trial, 2% sucrose + 0.5% yeast extract solution or sterile deionized water (control) was applied to the experiment plots. Twelve hours post-treatment (at 0600 hours), leaf samples were collected and yeast colony-forming units (cfu) were enumerated by dilution plating. This process was repeated at 1200, 1800, and 2400 hours in each trial. Significant differences were observed between the number of yeast cfu and the time at which the samples were collected. On average, the number of yeast cfu recovered was significantly less at 1800 hours and significantly greatest at 2400 hours when compared with all other sampling times. Averaged over all time intervals, we observed a trend of increased yeast abundance in turf treated with the nutrient solution compared with control treatments. In a separate investigation, atmospheric yeast abundance above the canopy of tall fescue was assessed in the morning (0900) and in the afternoon (1500) using a Thermo Andersen single stage viable particle sampler. In 5 of the 6 trials of this experiment, atmospheric yeast abundance was significantly greater in the morning than in the afternoon. Results suggest the following colonization model: phylloplane yeasts on tall fescue reproduce during the late evening and early morning, stabilize during the late morning and early afternoon through exchange of immigrants and emigrants, and decline during the late afternoon and (or) early evening. PMID:18389002

Nix, Shannon S; Burpee, Leon L; Jackson, Kimberly L; Buck, James W

2008-04-01

179

Growing tall-grass energy crops on sewage effluent spray field at Tallahassee, FL  

SciTech Connect

Six tall tropical grasses, N-51, PI 300086, and Merkeron elephantgrass (Pennisetum purpureum Schum.) and US 72-1153, US 56-9 and L 79-1002 energy cane (Saccharum sp.) and Alamo switchgrass (Panicum virgatum L.) were planted on the sewage effluent spray field of the city of Tallahassee, FL on January 6, 1993. Effluent with a total N content of 18 mg/1 was applied at the average rate of about 65 mm per week. In 1993, the plants grew well but we had difficulty with irrigation not reaching the experimental area during a drought. Seasonal dry matter biomass from Merkeron, PI 300086 and N-51 elephantgrass was 16.0, 18.2 and 16.4 Mg ha{sup -1}, and for L79-1002, US 72-1153 and US 56-9 energy canes was 22.6, 13.0 and 6.4 Mg ha{sup -1}, respectively. The second season all the grasses had excellent growth during season but, cattle broke in and harvested plots for us. In 1995 plots were split and low and high fertilizer rates applied. The average dry matter biomass production for 1995 season over the surviving five tropical tall grasses remaining was 28.7 Mg ha{sup -1} at low fertilizer rate and 32.2 Mg ha{sup -1} at high fertilizer rate. The annual oven dry biomass yields were 3 5.3, 34.8 and 27.7 Mg ha{sup -1} for the elephantgrass entries, Merkeron, N-51 and PI 300086 and 28.7 and 25.8 Mg ha{sup -1} for US 72-1153 and L79-1002 energy canes, respectively. All grass plants suffered N deficiency each winter and spring until N fertilizer was applied. The tall grass energy crops can be successfully grown on sewage effluent fields of cities in Lower South, USA.

Prine, G.M.; McConnell, W.V. [Univ. of Florida, Gainesville, FL (United States)

1996-12-31

180

Forages and pastures symposium: managing the tall fescue-fungal endophyte symbiosis for optimum forage-animal production.  

PubMed

Alkaloids produced by the fungal endophyte (Neotyphodium coenophialum) that infects tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] are a paradox to cattle production. Although certain alkaloids impart tall fescue with tolerances to environmental stresses, such as moisture, heat, and herbivory, ergot alkaloids produced by the endophyte can induce fescue toxicosis, a malady that adversely affects animal production and physiology. Hardiness and persistence of tall fescue under limited management can be attributed to the endophyte, but the trade-off is reduced cattle production from consumption of ergot alkaloids produced by the endophyte. Improved understanding and knowledge of this endophyte-grass complex has facilitated development of technologies and management systems that can either mitigate or completely alleviate fescue toxicosis. This review discusses the research results that have led to development of 5 management approaches to either reduce the severity of fescue toxicosis or alleviate it altogether. Three approaches manipulate the endophyte-tall fescue complex to reduce or alleviate ergot alkaloids: 1) use of heavy grazing intensities, 2) replacing the toxic endophyte with nonergot alkaloid-producing endophytes, and 3) chemical suppression of seed head emergence. The remaining 2 management options do not affect ergot alkaloid concentrations in fescue tissues but are used 1) to avoid grazing of tall fescue with increased ergot alkaloid concentrations in the late spring and summer by moving cattle to warm-season grass pasture and 2) to dilute dietary alkaloids by interseeding clovers or feeding supplements. PMID:23307847

Aiken, G E; Strickland, J R

2013-05-01

181

Gamma secretase inhibitors enhance vincristine-induced apoptosis in T-ALL in a NOTCH-independent manner.  

PubMed

Activating mutations in the NOTCH1 gene are found in over 50 % of T-ALL cases. Since Notch signaling contributes to the leukemia cell survival and growth, targeting Notch signaling using ?-secretase inhibitors (GSI) has been proposed as a molecularly targeted therapy for the treatment of T-ALL. However, not all T-ALL with NOTCH1 activating mutations respond to GSI treatment. We examined whether GSI could enhance the cytotoxic effect of anti-leukemic agents in the GSI-resistant T-ALL cells although GSI does not have anti-tumor effect as a single agent. GSI significantly increased cell death induced by Vincristine (VCR) but not other anti-leukemic drugs (Methotrexate, Asparaginase, and Cytarabine). The GSI effect in enhancing VCR efficacy was not the result of inhibition of Notch signaling. GSI augmented VCR-induced mitotic arrest, followed by apoptosis. GSI accelerated VCR-triggered loss of mitochondrial membrane potential and caspase-mediated apoptosis. Our finding suggests that GSI has other functions besides inhibiting Notch signaling in T-ALL and incorporating GSI into the conventional regimen containing VCR may offer therapeutic advantage by potentiating VCR treatment in leukemia patients. PMID:25156146

Yoon, Sun-Ok; Zapata, Mariana C; Singh, Akannsha; Jo, Wol Soon; Spencer, Nakia; Choi, Yong Sung

2014-11-01

182

Nano-Machines Achieve Huge Mechanical Breakthrough  

E-print Network

NANO TECH Nano-Machines Achieve Huge Mechanical Breakthrough Dublin, Ireland (SPX) Sep 08, 2005 that use molecular 'nano'-machines of this kind to help perform physical tasks. Nano-machines could also owners set to return to battered Orleans l Six dead, two missing after heavy rains hit Page 1 of 3Nano

Leigh, David A.

183

Antibody binding of circulating ergot alkaloids in cattle grazing tall fescue.  

PubMed

Direct evidence linking alkaloids found in endophyte-infected tall fescue forage with the livestock disorder known as fescue toxicosis is lacking. Physiologic effects of fescue toxicosis include reduced serum prolactin concentration in cattle. A monoclonal antibody specific to the lysergic moiety of ergot alkaloids was developed in mice after creating an immunogen by linking lysergol to human serum albumin. The antibody was specific to the lysergic moiety and, therefore, it cross-reacted with ergot alkaloids, lysergic acid, and lysergol. The antibody did not cross-react with alkaloid derivatives that had bromated or hydrogenated lysergic ring moieties. Fescue toxicosis conditions were elicited in yearling Angus steers by permitting them to graze endophyte-infected tall fescue containing > 650 micrograms/kg of ergovaline for 60 days. Passive immunization of steers by infusion of the monoclonal antibody increased serum prolactin concentration by 7 ng/ml, beginning immediately after infusion. Control steers did not respond to treatment with bovine serum albumin. Active immunization of yearling Angus heifers with immunogens containing lysergol or ergonovine linked to human serum albumin resulted in an antibody response. PMID:8192270

Hill, N S; Thompson, F N; Dawe, D L; Stuedemann, J A

1994-03-01

184

Isolation and characterization of a chlorophyll degradation regulatory gene from tall fescue.  

PubMed

The non-yellowing gene (NYE1), initially identified from Arabidopsis, is a key regulatory gene responsible for chlorophyll degradation during senescence. Here, FaNYE1, an orthologue of AtNYE1, was further identified from a major type of cool-season turf grass, tall fescue (Festuca arundinacea Schreb.), by RACE-PCR. It consists of 1,441 bp, with an open reading frame of 834 bp, encoding a predicted polypeptide of 278 amino acids. Sequence similarity as well as exon and intron characteristics clearly suggested that FaNYE1 encoded an AtNYE1-like chloroplast protein. FaNYE1 could be strongly induced by dark treatment and natural senescence. FaNYE1, driven by a 1.5 kb upstream fragment of AtNYE1, could rescue the stay-green phenotype of nye1-1. Constitutive overexpression of FaNYE1 in Arabidopsis resulted in the whole spectrum of leaf yellowing phenotypes, the severity of which correlates with its transcript level. These results collectively indicate that FaNYE1 might play an important regulatory role in chlorophyll degradation during senescence in tall fescue, and therefore is a valuable gene for improving the green period or lawn color of turf grasses by genetic engineering. PMID:21327390

Wei, Qiang; Guo, Yujuan; Kuai, Benke

2011-07-01

185

Chemotaxis disruption in Pratylenchus scribneri by tall fescue root extracts and alkaloids.  

PubMed

Tall fescue (Festuca arundinacea) forms a symbiotic relationship with the clavicipitalean fungal endophyte Neotyphodium coenophialum. Endophyte-infected grass is tolerant to nematode, but the factors responsible are unknown. One objective of this work was to determine if root extracts of tall fescue effected chemoreceptor activity of Pratylenchus scribneri by using an in vitro chemoreception bioassay. Another objective was to determine if specific ergot alkaloids (ergovaline, ergotamine, a-ergocryptine, ergonovine), and loline alkaloids, all produced by the fungal endophyte, altered chemotaxis with this bioassay. Methanolic extract from roots altered chemotaxis activities in this nematode but only from roots of plants cultured 45 > or = d, which repelled nematodes. Extracts prepared from noninfected grasses were attractants. This assay indicated that the alkaloids were either repellents or attractants. N-formylloline was an attractant at concentrations of 20 microg/ml and lower, while at higher concentrations it was a repellent. Ergovaline, the major ergot alkaloid produced by the endophyte, was repellent at both high and low concentrations and caused complete death of the nematodes. PMID:19575265

Bacetty, Ada A; Snook, Maurice E; Glenn, Anthony E; Noe, James P; Nagabhyru, Padmaja; Bacon, Charles W

2009-07-01

186

A clinical and patch test study in a tall-oil rosin factory.  

PubMed

Rosin of different sources is commonly used in many technical products and is known to cause contact allergy. The aim of the present investigation was to study the frequency of occupational dermatoses and of contact allergy to rosin in a factory producing tall-oil rosin. 163/180 present employees and 17/35 former employees participated in the study, which consisted of interview, clinical examination and patch testing with a standard series and additional rosins. 1/4 of those examined had some kind of current skin lesion. There were 10 cases of hand eczema. 7 subjects were patch-test-positive to gum rosin in the standard series. This frequency is about the same as among dermatitis patients at our clinic. Only 1 reaction to tall-oil rosin and none to the modified rosins tested were found. No relation between a positive patch test reaction to rosin and current skin disease could be established. No case of ongoing occupational skin disease was proved. PMID:7750248

Färm, G; Lidén, C; Karlberg, A T

1994-08-01

187

Oncogenesis of T-ALL and nonmalignant consequences of overexpressing intracellular NOTCH1  

PubMed Central

Mutations resulting in overexpression of intracellular Notch1 (ICN1) are frequently observed in human T cell acute lymphoblastic leukemia (T-ALL). We have determined the consequences of ICN1 overexpression from retroviral vectors introduced into bone marrow cells. Early consequences are the generation of polyclonal nontumorigenic CD4+8+ T cell receptor (TCR)-??+ cells that do not qualify as tumor precursors despite the observation that they overexpress Notch 1 and c-Myc and degrade the tumor suppressor E2A by posttranslational modification. The first tumorigenic cells are detected among more immature CD4?8+TCR-??? cells that give rise to monoclonal tumors with a single, unique TCR-? chain and diverse TCR-? chains, pinpointing malignant transformation to a stage after pre-TCR signaling and before completion of TCR-? rearrangement. In T-ALL, E2A deficiency is accompanied by further transcriptional up-regulation of c-Myc and concomitant dysregulation of the c-Myc-p53 axis at the transcriptional level. Even though the tumors consist of phenotypically heterogeneous cells, no evidence for tumor stem cells was found. As judged by array-based comparative genomic hybridization (array CGH) and spectral karyotype (SKY) analysis, none of the tumors arise because of genomic instability. PMID:18981238

Li, Xiaoyu; Gounari, Fotini; Protopopov, Alexei; Khazaie, Khashayarsha; von Boehmer, Harald

2008-01-01

188

Oncogenesis of T-ALL and nonmalignant consequences of overexpressing intracellular NOTCH1.  

PubMed

Mutations resulting in overexpression of intracellular Notch1 (ICN1) are frequently observed in human T cell acute lymphoblastic leukemia (T-ALL). We have determined the consequences of ICN1 overexpression from retroviral vectors introduced into bone marrow cells. Early consequences are the generation of polyclonal nontumorigenic CD4(+)8(+) T cell receptor (TCR)-alphabeta(+) cells that do not qualify as tumor precursors despite the observation that they overexpress Notch 1 and c-Myc and degrade the tumor suppressor E2A by posttranslational modification. The first tumorigenic cells are detected among more immature CD4(-)8(+)TCR-alphabeta(-) cells that give rise to monoclonal tumors with a single, unique TCR-beta chain and diverse TCR-alpha chains, pinpointing malignant transformation to a stage after pre-TCR signaling and before completion of TCR-alpha rearrangement. In T-ALL, E2A deficiency is accompanied by further transcriptional up-regulation of c-Myc and concomitant dysregulation of the c-Myc-p53 axis at the transcriptional level. Even though the tumors consist of phenotypically heterogeneous cells, no evidence for tumor stem cells was found. As judged by array-based comparative genomic hybridization (array CGH) and spectral karyotype (SKY) analysis, none of the tumors arise because of genomic instability. PMID:18981238

Li, Xiaoyu; Gounari, Fotini; Protopopov, Alexei; Khazaie, Khashayarsha; von Boehmer, Harald

2008-11-24

189

Baseline report - tall upland shrubland at the Rocky Flats Environmental Technology Site  

SciTech Connect

Rocky Flats Environmental Technology Site (Site) is located on the Colorado Piedmont east of the Front Range between Boulder and Golden. At an elevation of approximately 6,000 feet, the Site contains a unique ecotonal mixture of mountain and prairie plant species, resulting from the topography and close proximity to the mountain front. The Buffer Zone surrounding the Industrial Area is one of the largest remaining undeveloped areas of its kind along the Colorado Piedmont. A number of plant communities at the Site have been identified as increasingly rare and unique by Site ecologists and the Colorado Natural Heritage Program (CNHP). These include the xeric tallgrass prairie, tall upland shrubland, wetlands, and Great Plains riparian woodland communities. Many of these communities support populations of increasingly rare animals as well, including the Preble`s meadow jumping mouse, grasshopper sparrow, loggerhead shrike, Merriam`s shrew, black crowned night heron, and Hops blue and Argos skipper butterflies. One of the more interesting and important plant communities at the Site is the tall upland shrubland community. It has been generally overlooked by previous Site ecological studies, probably due to its relatively small size; only 34 acres total. Although mentioned in a plant community ordination study conducted by Clark et al. and also in the Site baseline ecological study, few data were available on this plant community before the present study.

NONE

1997-03-01

190

NanoSense  

NSDL National Science Digital Library

The NSF-sponsored NanoSense project was created to address the question of how to teach nanoscale science at the secondary level. This web site contains the materials developed by the NanoSense team, which include four comprehensive curriculum units to introduce teachers and students to nanotechnology. Each unit has been classroom tested and provides extensive content support. Users may download cost-free lesson plans aligned to national standards, Power Point lecture materials, student activity guides, and related assessments. The materials were developed in a modular fashion to enable use for a short classroom introduction or a longer experiential learning project. Topics include 1) introduction to nanotechnology, 2) light and matter interactions, 3) solar energy and nanoscience, and 4) the water crisis.

2009-06-05

191

Short-term administration of tall oil phytosterols improves plasma lipid profiles in subjects with different cholesterol levels.  

PubMed

To assess the short-term cholesterol-lowering potential of sitostanol-containing tall oil plant sterols, 22 subjects consumed fixed-food diets over two 10-day periods with or without 21.2 mg/kg body weight/d tall oil phytosterols (sitosterol 62%, sitostanol 21%, campesterol 16%, and campestanol 1%) in a randomized crossover study design. On day 10 of each diet, plasma lipoprotein cholesterol levels, plasma phytosterol concentrations, and cholesterol biosynthesis rates were determined. Total cholesterol (TC) and low-density lipoprotein (LDL) cholesterol levels were lower (P < .01) after administration of tall oil phytosterol (4.7 +/- 0.3 and 3.0 +/- 0.3 mmol/L, respectively) versus placebo (5.0 +/- 0.3 and 3.2 +/- 0.3 mmol/L, respectively). Tall oil treatment had no effect on the plasma high-density lipoprotein (HDL) cholesterol level (1.1 +/- 0.1 mmol/L) versus placebo (1.1 +/- 0.1 mmol/L). Similarly, plasma triglyceride (TG) levels did not differ between tall oil (1.3 +/- 0.2 mmol/L) and placebo (1.4 +/- 0.2 mmol/L) treatments. Plasma campesterol (15.8 +/- 3.7 mmol/mol cholesterol) and sitosterol (6.0 +/- 2.1 mmol/mol cholesterol) levels were not different after tall oil treatment versus placebo treatment (15.4 +/- 2.3 and 6.4 +/- 2.0 mmol/mol cholesterol, respectively). Plasma sitostanol levels were essentially undetectable. No difference was observed in cholesterol biosynthesis between tall oil (0.045 +/- 0.004 pools/d) and placebo (0.034 +/- 0.004 pools/d) treatments; however, the effect of treatments in subjects with different cholesterol levels varied. In subjects with lower cholesterol values, the red blood cell cholesterol fractional synthesis rate (FSR) increased from 0.0291 +/- 0.0054 pools/d after placebo to 0.0509 +/- 0.0049 pools/d (P < .05) after phytosterol treatment. In subjects with higher cholesterol values, the red blood cell cholesterol FSR did not change significantly after treatment. These results demonstrate the short-term efficacy of tall oil plant sterols as cholesterol-lowering agents. PMID:9627377

Jones, P J; Howell, T; MacDougall, D E; Feng, J Y; Parsons, W

1998-06-01

192

Fatty and resin acid analysis in tall oil products via supercritical fluid extraction-supercritical fluid reaction using enzymatic catalysis.  

PubMed

Supercritical fluid extraction (SFE) is combined with supercritical fluid reaction (SFR) in an analytical mode to assess tall oil products for their fatty or resin acid content or both. The SFR consists of an inline enzymatically catalyzed reaction in which a lipase transesterifies specific lipids with methanol. The SFE-SFR sequence is conducted employing commercially available extractors using supported lipases in the extraction cell to form methyl esters. In this study, six different commercially available lipases are screened for activity. The SFE-SFR extracts are analyzed by capillary gas chromatography and supercritical fluid chromatography and then compared with tall oil products derivatized by conventional chemical derivatization techniques. PMID:11471988

Taylor, S L; King, J W

2001-07-01

193

Electrospray neutralization process and apparatus for generation of nano-aerosol and nano-structured materials  

DOEpatents

The claimed invention describes methods and apparatuses for manufacturing nano-aerosols and nano-structured materials based on the neutralization of charged electrosprayed products with oppositely charged electrosprayed products. Electrosprayed products include molecular ions, nano-clusters and nano-fibers. Nano-aerosols can be generated when neutralization occurs in the gas phase. Neutralization of electrospan nano-fibers with molecular ions and charged nano-clusters may result in the formation of fibrous aerosols or free nano-mats. Nano-mats can also be produced on a suitable substrate, forming efficient nano-filters.

Bailey, Charles L. (Cross Junction, VA); Morozov, Victor (Manassas, VA); Vsevolodov, Nikolai N. (Kensington, MD)

2010-08-17

194

632 IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 49, NO. 3, AUGUST 2007 Electromagnetic Fields at the Top of a Tall Building  

E-print Network

than 100 m. In order to optimize lightning protection means of tall buildings in such an area Fields at the Top of a Tall Building Associated With Nearby Lightning Return Strokes Yoshihiro Baba and azimuthal magnetic field H due to lightning return strokes in the presence and in the absence of a building

Florida, University of

195

Ergopeptine Alkaloid Production by Endophytes in a Common Tall Fescue Genotype iN. s. Hill,* W.A. Parrott, and D. D. Pope  

E-print Network

into the vascular system of cattle (Bos taurus) have reproduced rescue toxicosis symptoms (G. Garner, 1990, personal communication). Livestock producers whodependon tall fescue as their grass base for forage systems therefore of 'Kentucky-31'tall fescue growing at the USDA-ARSSouthern Piedmont Soil and Water Conse

Parrott, Wayne

196

Experimental and theoretical study of ion distributions near 300 m tall steps on rf-biased wafers in high density plasmas  

E-print Network

voltage is also usually applied to the chuck, influencing the energy of the ions striking the waferExperimental and theoretical study of ion distributions near 300 m tall steps on rf-biased wafers, energy distributions, and angular distributions close to 300 m tall ``steps'' on rf-biased wafers in high

Economou, Demetre J.

197

Seasonal patterns of CO 2 and water vapor exchange of the tall and short height forms of Spartina alterniflora Loisel in a Georgia salt marsh  

Microsoft Academic Search

Seasonal patterns of the responses of net photosynthesis, transpiration, leaf diffusive conductance, water-use efficiency and respiration to temperature, light and CO2 concentration were determined on intact plants of the short and tall height forms of Spartina alterniflora. The studies were conducted on in situ plants in an undisturbed marsh community on Sapelo Island, Ga. Net photosynthesis of the tall form

J. R. Giurgevich; E. L. Dunn

1979-01-01

198

The medicalisation of ‘tall’ girls: A discourse analysis of medical literature on the use of synthetic oestrogen to reduce female height  

Microsoft Academic Search

Endocrine research in the 1930s increased and extended the use of sex hormones as medical therapies in an unprecedented way, especially for female ailments. In the 1950s the therapeutic use of sex hormones extended to the treatment of ‘tall’ girls. Ambiguity in the definition of the ‘tall’ girl, the arbitrary nature of the treatment decision, and diversity in the therapeutic

Jo-Anne Rayner; Priscilla Pyett; Jill Astbury

2010-01-01

199

46 CFR 32.55-50 - Ventilation of tankships that have a keel laying date on or after January 1, 1975-T/ALL.  

Code of Federal Regulations, 2013 CFR

...tankships that have a keel laying date on or after January 1, 1975-T/ALL. 32.55-50 Section 32.55-50 Shipping COAST...tankships that have a keel laying date on or after January 1, 1975—T/ALL. Each tankship that has a keel laying date on...

2013-10-01

200

46 CFR 32.55-50 - Ventilation of tankships that have a keel laying date on or after January 1, 1975-T/ALL.  

Code of Federal Regulations, 2010 CFR

...tankships that have a keel laying date on or after January 1, 1975-T/ALL. 32.55-50 Section 32.55-50 Shipping COAST...tankships that have a keel laying date on or after January 1, 1975—T/ALL. Each tankship that has a keel laying date on...

2010-10-01

201

46 CFR 32.55-50 - Ventilation of tankships that have a keel laying date on or after January 1, 1975-T/ALL.  

Code of Federal Regulations, 2012 CFR

...tankships that have a keel laying date on or after January 1, 1975-T/ALL. 32.55-50 Section 32.55-50 Shipping COAST...tankships that have a keel laying date on or after January 1, 1975—T/ALL. Each tankship that has a keel laying date on...

2012-10-01

202

46 CFR 32.55-20 - Venting of cargo tanks of tankships constructed on or after July 1, 1951-T/ALL.  

Code of Federal Regulations, 2010 CFR

...cargo tanks of tankships constructed on or after July 1, 1951-T/ALL. 32.55-20 Section 32.55-20 Shipping COAST...cargo tanks of tankships constructed on or after July 1, 1951—T/ALL. (a) Venting required. (1) On all...

2010-10-01

203

46 CFR 32.55-20 - Venting of cargo tanks of tankships constructed on or after July 1, 1951-T/ALL.  

Code of Federal Regulations, 2013 CFR

...cargo tanks of tankships constructed on or after July 1, 1951-T/ALL. 32.55-20 Section 32.55-20 Shipping COAST...cargo tanks of tankships constructed on or after July 1, 1951—T/ALL. (a) Venting required. (1) On all...

2013-10-01

204

Numerical modeling of initiation of lightning leaders from tall structures by sprite-producing lightning discharges  

NASA Astrophysics Data System (ADS)

It is well established by now that large charge transfers between cloud and ground in positive cloud-to-ground lightning discharges (+CGs) can lead to transient electric field enhancements at mesospheric and lower ionospheric altitudes. In these events the electric field can exceed the conventional breakdown field and lead to formation of transient luminous events referred to as sprites and sprite halos [e.g., Qin et al., JGR, 116, A06305, 2011, and references therein]. Stanley and Heavner [Proc. 12th International Conference on Atmospheric Electricity, Versailles, France, 2003] reported that the large and rapid charge transfer of +CGs producing sprites can also initiate upward positive leaders from tall structures. These authors also presented data analysis indicating that structures with >400 m height have a significantly enhanced probability of launching upward positive leaders that may culminate in a -CG return stroke to the structure. The effect can be understood by considering the field intensification at the top of the tall structure combined with fast application of the field preventing formation and shielding effects of ion corona [Brook et al., JGR, 66, 3967, 1961]. In the present work we utilize the most recent modeling approaches developed at Penn State [e.g., Riousset et al., JGR, 115, A00E10, 2010] to quantify the conditions leading to initiation of positive leaders from tall structures following sprite-producing +CGs. Experiments show that the streamer zone transforms into leader when voltage drop along the streamer zone exceeds 400 kV [e.g., Aleksandrov et al., J. Phys. D: Appl. Phys., 38, 1225, 2005]. For a formed leader half of the voltage drops in the streamer zone, and another half in free space ahead of the streamer zone [Bazelyan and Raizer, Lightning physics and lightning protection, p. 62, 2000]. In our analysis therefore we assume that minimum voltage at the tip of the tower should exceed 800 kV for sustainment of upward propagating leader. The results indicate, in particular, that a charge moment change of 390 C km in a +CG can lead to leader initiation from a 457 m tower approximately 15 km from the +CG, in good agreement with observations reported in [Stanley and Heavner, 2003]. We report detailed relationships, including analytical estimates and numerical modeling results, providing information on the charge moment charges versus tower height and radial position with respect to +CG required for initiation of upward leaders.

Pasko, V. P.

2011-12-01

205

Ligandless surfactant mediated solid phase extraction combined with Fe?O? nano-particle for the preconcentration and determination of cadmium and lead in water and soil samples followed by flame atomic absorption spectrometry: multivariate strategy.  

PubMed

In the present study, a microextraction technique combining Fe3O4 nano-particle with surfactant mediated solid phase extraction ((SM-SPE)) was successfully developed for the preconcentration/separation of Cd(II) and Pb(II) in water and soil samples. The analytes were determined by flame atomic absorption spectrometry (FAAS). The effective variables such as the amount of adsorbent (NPs), the pH, concentration of non-ionic (TX-114) and centrifugation time (min) were investigated by Plackett-Burman (PBD) design. The important variables were further optimized by central composite design (CCD). Under the optimized conditions, the detection limits (LODs) of Cd(II) and Pb(II) were 0.15 and 0.74 µg/L, respectively. The validation of the proposed procedure was checked by the analysis of certified reference materials of TMDA 53.3 fortified water and GBW07425 soil. The method was successfully applied for the determination of Cd(II) and Pb(II) in water and soil samples. PMID:24530734

Jalbani, N; Soylak, M

2014-04-01

206

Magnetic Nano-Materials: Truly Sustainable Green Chemistry Nano Catalysis  

EPA Science Inventory

We envisioned a novel nano-catalyst system, which can bridge the homogenous and heterogeneous system, and simultaneously be cheaper, easily accessible (sustainable) and possibly does not require elaborate work-up. Because of its nano-size, i.e. high surface area, the contact betw...

207

A comparative study of growth strategies in two varieties of Arrhenatherum elatius  

Microsoft Academic Search

Growth strategies of the two varieties of Arrhenatherum elatius were studied. The two varieties studied were: onion couch, which produces bulbous swollen internodes and is an arable weed of local importance, whilst tall oat-grass is more widely distributed. An experiment in which the two varieties were grown at different densities in monoculture and were harvested at intervals, highlighted various aspects

Amin U. Khan; Alan J. Morton

1994-01-01

208

Parallel Computations of Natural Convection Flow in a Tall Cavity Using an Explicit Finite Element Method  

SciTech Connect

The Galerkin Finite Element Method was used to predict a natural convection flow in an enclosed cavity. The problem considered was a differentially heated, tall (8:1), rectangular cavity with a Rayleigh number of 3.4 x 10{sup 5} and Prandtl number of 0.71. The incompressible Navier-Stokes equations were solved using a Boussinesq approximation for the buoyancy force. The algorithm was developed for efficient use on massively parallel computer systems. Emphasis was on time-accurate simulations. It was found that the average temperature and velocity values can be captured with a relatively coarse grid, while the oscillation amplitude and period appear to be grid sensitive and require a refined computation.

Dunn, T.A.; McCallen, R.C.

2000-10-17

209

On cat's eyes and multiple disjoint cells natural convection flow in tall tilted cavities  

NASA Astrophysics Data System (ADS)

Natural convection fluid flow in air-filled tall tilted cavities is studied numerically with a direct projection method applied on the unsteady Boussinesq approximation in primitive variables. The study is focused on the so called cat's eyes and multiple disjoint cells as the aspect ratio A and the angle of inclination ? of the cavity vary. Results have already been reported with primitive and stream function-vorticity variables. The former are validated with the latter ones, which in turn were validated through mesh size and time-step independence studies. The new results complemented with the previous ones lead to find out the fluid motion and heat transfer invariant properties of this thermal phenomenon, which is the novelty here.

Báez, Elsa; Nicolás, Alfredo

2014-10-01

210

Recent Results From the NOAA/ESRL GMD Tall Tower Network  

NASA Astrophysics Data System (ADS)

We will present a summary of new results from NOAA Earth System Research Laboratory`s Tall Tower greenhouse gas monitoring network. The tower network is operated by the Global Monitoring Division, which also maintains the global Cooperative Air Sampling network and a network of aircraft profiling sites over North America. Tall tower CO2 mixing ratio measurements are sensitive to upwind fluxes over scales of hundreds of kilometers, and the primary objective of the tower network is to obtain regionally representative carbon flux estimates for the North American continent. Mixing ratios of CO2 and CO are measured semi-continuously at the towers, and the KWKT-TV tower site near Moody, TX has recently also been equipped with sensors to measure radon and O3. Daily flask samples are collected at the KWKT tower and analyzed for CO2, CO, CH4, SF6, N2O, H2, stable isotopes of CO2 and CH4, COS, and a variety of halocarbon and hydrocarbon species. Daily flask sampling will be implemented at all tower sites within the next few years. We have used the Stochastic Time Inverted Lagrangian Transport (STILT) model to investigate upwind influences on the tower observations. CO measurements provide an indicator of polluted air masses, and we will present a summary of the frequency and origin of pollution events observed at the towers. We will present an analysis of the primary factors contributing to observed CO2 variability along with average seasonal and diurnal cycles of CO2 at the tower sites. Tower measurements are being used to evaluate atmospheric transport models in the context of the Transcom Continuous experiment and are an important constraint for CO2 data assimilation systems that produce regional to global carbon flux estimates with up to weekly resolution.

Andrews, A. E.; Tans, P. P.; Peters, W.; Hirsch, A.; Sweeney, C.; Petron, G.; Kofler, J.; Zhao, C.; Masarie, K.; Wofsy, S. C.; Matross, D. M.; Mahadevan, P.; Longo, M.; Gerbig, C.; Lin, J. C.

2006-12-01

211

Tall fescue (Festuca arundinacea Schreb.) is the pre-dominant forage species on over one million acres of  

E-print Network

Tall fescue (Festuca arundinacea Schreb.) is the pre- dominant forage species on over one million or harvested at a proper stage of growth. Despite its positive agronomic traits, many Virginia producers to encroach over time until it becomes the dominant forage in a pasture. Its tendency for encroachment

Liskiewicz, Maciej

212

Intergeneric somatic hybridization in Gramineae: somatic hybrid plants between tall fescue ( Festuca arundinacea Schreb.) and Italian ryegrass ( Lolium multiflorum Lam.)  

Microsoft Academic Search

Tall fescue (Festuca arundinacea Schreb.) protoplasts, inactivated by iodoacetamide, and non-morphogenic Italian ryegrass (Lolium multiflorum Lam.) protoplasts, both derived from suspension cultures, were electrofused and putative somatic hybrid plants were recovered. Two different genotypic fusion combinations were carried out and several green plants were regenerated in one of them. With respect to plant habitus, leaf and inflorescence morphology, the regenerants

Tadashi Takamizo; German Spangenberg; Ken-ichi Suginobu; Ingo Potrykus

1991-01-01

213

Effects of nitrogen applied after the last cut in autumn on a tall fescue sward. I. Analysis of morphogenesis  

E-print Network

(1974) has obtained a very favorable effect on perennial rye- grass. Murphy (1977) reported; The effects of applying nitrogen to grass after the last cut in autumn on growth the following spring was investigated in a series trials at Lusignan, west central France. The grass used was tall fescue (Festuca

Boyer, Edmond

214

LIMING OF TWO ACIDIC SOILS IMPROVED GRASS TETANY RATIO OF STOCKPILED TALL FESCUE WITHOUT INCREASING PLANT AVAILABLE PHOSPHORUS  

Microsoft Academic Search

Previous research demonstrated that phosphorus (P) fertilization of tall fescue (Festuca arundinacea Schreb.) pastures on acidic soils increased leaf P, magnesium (Mg), and calcium (Ca) concentrations and reduced the risk of grass tetany. It has been suggested that liming could have a similar effect by increasing soil pH and remobilizing sorbed P. To investigate this option, calcitic or dolomitic limestone

Elizabeth J. Hamilton; Randall J. Miles; Krystyna Lukaszewska; Melissa Remley; Matt Massie; Dale G. Blevins

2012-01-01

215

RESPONSE OF TALL STEEL BUILDINGS IN SOUTHERN CALIFORNIA TO THE MAGNITUDE 7.8 SHAKEOUT SCENARIO EARTHQUAKE  

E-print Network

in the Great Southern California Shakeout Scenario in 2008, a large-scale earthquake response exercise one striking southern California. Scenario Earthquake The scenario earthquake chosen is a magnitude 7RESPONSE OF TALL STEEL BUILDINGS IN SOUTHERN CALIFORNIA TO THE MAGNITUDE 7.8 SHAKEOUT SCENARIO

Krishnan, Swaminathan

216

The effect of a tall tower on flow and dispersion through a model urban neighborhood : Part 1. Flow characteristics  

Microsoft Academic Search

Wind tunnel and computational fluid dynamics (CFD) studies were performed to examine the effect of a tall tower on the flow around an otherwise uniform array of buildings. The model used in both the wind tunnel and CFD studies was designed to simulate an area of Brooklyn, NY, where blocks of residential row houses form a neighborhood bordering a major

David K. Heist; Laurie A. Brixey; Jennifer Richmond-Bryant; George E. Bowker; Steven G. Perry; Russell W. Wiener

2009-01-01

217

NanoDrop 3300 Fluorospectrometer  

E-print Network

NanoDrop 3300 Fluorospectrometer V2.7 User's Manual #12;The information in this publication are the property of Thermo Fisher Scientific Inc. and its subsidiaries. NanoDrop is a trademark of Thermo Fisher 19810 U.S.A. Telephone: 302-479-7707 Fax: 302-792-7155 E-mail: info@nanodrop.com www.nanodrop

Fygenson, Deborah Kuchnir

218

Animal performance and economic comparison of novel and toxic endophyte tall fescues to cool-season annuals.  

PubMed

Increased costs of annual establishment of small grain pasture associated with fuel, machinery, and labor are eroding the profitability of stocker cattle enterprises. Interest has therefore increased in development of cool-season perennial grasses that are persistent and high quality. This study occurred on 24 ha (divided into thirty 0.81-ha paddocks) located at the University of Arkansas Division of Agriculture Livestock and Forestry Branch Station, near Batesville. Two tall fescue (Festuca arundinacea Schreb.) cultivars infected with novel endophytes (NE), Jesup infected with AR542 endophyte (Jesup AR542), and HiMag infected with Number 11 endophyte (HM11) were established in September 2002. Jesup AR542 and HM11 were compared with endemic endophyte Kentucky 31 (KY-31) tall fescue; wheat (Triticum aestivum L.) and cereal rye (WR, Secale cereale L.) planted in September 2003, 2004, and 2005; and annual ryegrass [RG, Lolium perenne L. ssp. multiflorum (Lam.) Husnot] planted in September 2004 and 2005. Each year, 3 steers (3.7 steers/ha) were placed on each pasture for fall and winter grazing, and 5 steers (6.2 steers/ha) were placed on each pasture for spring grazing. Animal performance is presented by year in the presence of a year x treatment interaction (P < 0.01). Body weight gain per hectare of steers grazing NE tall fescue was greater (P < 0.01) than those of KY-31 and WR during 2003 to 2004, whereas in 2004 to 2005, BW gain per hectare of steers grazing NE and RG did not differ (P < or = 0.29) and was greater (P < 0.01) than that of WR, which was greater (P < 0.01) than that of KY-31. During 2005 to 2006, BW gain per hectare was greater (P < 0.01) for steers grazing RG than those of NE and WR, which did not differ (P > or = 0.14). Body weight gain per hectare was least (P < 0.01) for steers grazing KY-31. Average net return of NE tall fescue was greater (P < 0.01) than KY-31, but profitability of NE did not consistently differ from cool-season annuals. Across the 3-yr study, NE tall fescue produced net returns per hectare of $219; this level of profitability would require 4 yr for a new planting of NE tall fescue to break even. Novel endophyte tall fescues offer potential benefits related to decreased risk of stand establishment of annual forage crops, longer growing season, and acceptable animal performance. PMID:18310498

Beck, P A; Gunter, S A; Lusby, K S; West, C P; Watkins, K B; Hubbell, D S

2008-08-01

219

Exploring Materials: Nano Gold  

NSDL National Science Digital Library

In this activity, learners discover that nanoparticles of gold can appear red, orange or even blue. They learn that a material can act differently when itâs nanometer-sized. Use this activity to explain how stained glass gets its different colors. Note: the cost for the materials in this activity is quite high. However, this is a one-time cost, since the nano gold is kept in vials at all time and thus should not be used up. SAFETY: Do not let visitors ingest the contents of the vials. Keep vials sealed shut. Use caution when handling the stained glass samples. Do not remove them from their protective case.

Network, Nanoscale I.; Sciencenter

2011-01-01

220

3-D Nano-Fiber Manufacturing by Controlled Pulling of Liquid Polymers using Nano-Probes  

E-print Network

3-D Nano-Fiber Manufacturing by Controlled Pulling of Liquid Polymers using Nano-Probes Amrinder S nano-fibers by using precise positioning and temperature control. AFM nano-probe is used to pull or extrude thermoset or thermoplastic polymers precisely to fabricate 3-D polymer nano-fiber structures

Sitti, Metin

221

EE 238 Engineering nano-systems EE 238 Engineering nano-systems  

E-print Network

EE 238 Engineering nano-systems Page 1 EE 238 Engineering nano-systems A.F.J. Levi Spring 2009, OHE This course is designed as an introduction to nano-technology, methods to control and exploit the new degrees of freedom delivered by nano-science, and the integration of nano-technology into systems. It is a hands

Levi, Anthony F. J.

222

EE 337 Engineering micro and nano-systems EE 337 Engineering micro and nano-systems  

E-print Network

EE 337 Engineering micro and nano-systems EE 337 Engineering micro and nano-systems A.F.J. Levi as an introduction to micro and nano-technology, methods to control and exploit the new degrees of freedom delivered by nano-science, and the integration of micro and nano-technology into systems. It is a hands

Levi, Anthony F. J.

223

GROWTH OFGROWTH OFGROWTH OFGROWTH OF BACTERIABACTERIABACTERIABACTERIA CONSORTIUMCONSORTIUMCONSORTIUMCONSORTIUM ONONONON NANO-NANO-NANO-NANO-CARBON ELECTRODECARBON ELECTRODECARBON ELECTRODECARBON ELECTRODE FOR POWER GENERATIONFOR POWER GENERATIONFOR POWER  

E-print Network

CONSORTIUMCONSORTIUMCONSORTIUMCONSORTIUM ONONONON NANO-NANO-NANO-NANO- CARBON ELECTRODECARBON ELECTRODECARBON ELECTRODECARBON ELECTRODE(CNTs) supported carbon fiber electrode has outstanding electronchemical properties in fuel cell application and generating power METHODS -Preparation of CNTs based carbon fiber-Preparation of CNTs based carbon fiber

Weiblen, George D

224

Molecular characterisation and interpretation of genetic diversity within globally distributed germplasm collections of tall fescue (Festuca arundinacea Schreb.) and meadow fescue (F. pratensis Huds.).  

PubMed

Allohexaploid tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum [Schreb.] Darbysh.) is an agriculturally important grass cultivated for pasture and turf world-wide. Genetic improvement of tall fescue could benefit from the use of non-domesticated germplasm to diversify breeding populations through the incorporation of novel and superior allele content. However, such potential germplasm must first be characterised, as three major morphotypes (Continental, Mediterranean and rhizomatous) with varying degrees of hybrid interfertility are commonly described within this species. As hexaploid tall fescue is also a member of a polyploid species complex that contains tetraploid, octoploid and decaploid taxa, it is also possible that germplasm collections may have inadvertently sampled some of these sub-species. In this study, 1,040 accessions from the publicly available United States Department of Agriculture tall fescue and meadow fescue germplasm collections were investigated. Sequence of the chloroplast genome-located matK gene and the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS) permitted attribution of accessions to the three previously known morphotypes and also revealed the presence of tall fescue sub-species of varying ploidy levels, as well as other closely related species. The majority of accessions were, however, identified as Continental hexaploid tall fescue. Analysis using 34 simple sequence repeat markers was able to further investigate the level of genetic diversity within each hexaploid tall fescue morphotype group. At least two genetically distinct sub-groups of Continental hexaploid tall fescue were identified which are probably associated with palaeogeographic range expansion of this morphotype. This work has comprehensively characterised a large and complex germplasm collection and has identified genetically diverse accessions which may potentially contribute valuable alleles at agronomic loci for tall fescue cultivar improvement programs. PMID:22222441

Hand, Melanie L; Cogan, Noel O I; Forster, John W

2012-04-01

225

*SINAM NANO SEMINAR * Center for Scalable and Integrated NAnoManufacturing (SINAM) -NSF  

E-print Network

*SINAM NANO SEMINAR * Center for Scalable and Integrated NAnoManufacturing (SINAM) - NSF Nanoscale and Integrated NAnoManufacturing (SINAM) Email:xz_asst@me.berkeley.edu Phone: 510.642.0390 Fax: 510.643.2311 #12;

Militzer, Burkhard

226

Nano surface generation of grinding process using carbon nano tubes  

Microsoft Academic Search

Nano surface finish has become an important parameter in the semiconductor, optical, electrical and mechanical industries.\\u000a The materials used in these industries are classified as difficult to machine materials such as ceramics, glasses and silicon\\u000a wafers. Machining of these materials up to nano accuracy is a great challenge in the manufacturing industry. Finishing of\\u000a micro components such as micro-moulds, micro-lenses

S. Prabhu; B. K. Vinayagam

2010-01-01

227

Silicon-carbon nano-structures to nano-tubes  

Microsoft Academic Search

There have been continuing efforts to stabilize silicon cage-type nano-structures or nano-tubes which can be used in similar ways as the carbon-based fullerene structures. This is due to the fact that the current semiconductor industries are based on silicon. Silicon carbide is the focus of scientific research due to its potential use even in extreme conditions, such as extreme high-temperature,

M. N. Huda; Leonard Kleinman; A. K. Ray

2006-01-01

228

NanoKids(TM)  

NSDL National Science Digital Library

NanoKids(TM) is an education and outreach program for intermediate-level (middle-school) students intended to increase their knowledge of nanotechnology and emerging research and technology in this field, which involves working with objects on the molecular and atomic scale (as small as one-billionth of a meter). Site materials include a series of self-contained lessons accompanied by animated videos and an online workbook for students. There is also a sample test and additional resources for teachers (slide presentations, games, and other materials). The site also offers an overview of the project and its participants, biographical "sketches" of the characters used in the animations, and one-page features that explain the nanometer scale, the countries and scientists involved in nanotechnology, and atoms, molecules, and bondng. Some materials on the site are available in Spanish.

229

Nano-optomechanical transducer  

DOEpatents

A nano-optomechanical transducer provides ultrabroadband coherent optomechanical transduction based on Mach-wave emission that uses enhanced photon-phonon coupling efficiencies by low impedance effective phononic medium, both electrostriction and radiation pressure to boost and tailor optomechanical forces, and highly dispersive electromagnetic modes that amplify both electrostriction and radiation pressure. The optomechanical transducer provides a large operating bandwidth and high efficiency while simultaneously having a small size and minimal power consumption, enabling a host of transformative phonon and signal processing capabilities. These capabilities include optomechanical transduction via pulsed phonon emission and up-conversion, broadband stimulated phonon emission and amplification, picosecond pulsed phonon lasers, broadband phononic modulators, and ultrahigh bandwidth true time delay and signal processing technologies.

Rakich, Peter T; El-Kady, Ihab F; Olsson, Roy H; Su, Mehmet Fatih; Reinke, Charles; Camacho, Ryan; Wang, Zheng; Davids, Paul

2013-12-03

230

Genotoxic effects of fumes from asphalt modified with waste plastic and tall oil pitch.  

PubMed

As the use of recycled materials and industrial by-products in asphalt mixtures is increasing, we investigated if recycled additives modify the genotoxicity of fumes emitted from asphalt. Fumes were generated in the laboratory at paving temperature from stone-mastic asphalt (SMA) and from SMA modified with waste plastic (90% polyethylene, 10% polypropylene) and tall oil pitch (SMA-WPT). In addition, fumes from SMA, SMA-WPT, asphalt concrete (AC), and AC modified with waste plastic and tall oil pitch (AC-WPT) were collected at paving sites. The genotoxicity of the fumes was studied by analysis of DNA damage (measured in the comet assay) and micronucleus formation in human bronchial epithelial BEAS 2B cells in vitro and by counting mutations in Salmonella typhimurium strains TA98 and YG1024. DNA damage was also assessed in buccal leukocytes from road pavers before and after working with SMA, SMA-WPT, AC, and AC-WPT. The chemical composition of the emissions was analysed by gas chromatography/mass spectrometry. The SMA-WPT fume generated in the laboratory induced a clear increase in DNA damage in BEAS 2B cells without metabolic activation. The laboratory-generated SMA fume increased the frequency of micronucleated BEAS 2B cells without metabolic activation. None of the asphalt fumes collected at the paving sites produced DNA damage with or without metabolic activation. Fumes from SMA and SMA-WPT from the paving sites increased micronucleus frequency without metabolic activation. None of the asphalt fumes studied showed mutagenic activity in Salmonella. No statistically significant differences in DNA damage in buccal leukocytes were detected between the pre- and post-shift samples collected from the road pavers. However, a positive correlation was found between DNA damage and the urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) after work shift, which suggested an association between occupational exposures during road paving and genotoxic effects. Our results indicate that fumes from SMA and SMA-WPT contain direct-acting genotoxic components. PMID:18499510

Lindberg, Hanna K; Väänänen, Virpi; Järventaus, Hilkka; Suhonen, Satu; Nygren, Jonas; Hämeilä, Mervi; Valtonen, Jarkko; Heikkilä, Pirjo; Norppa, Hannu

2008-05-31

231

Comparative analysis of transgenic tall fescue (Festuca arundinacea Schreb.) plants obtained by Agrobacterium-mediated transformation and particle bombardment.  

PubMed

Agrobacterium-mediated transformation and particle bombardment are the two most widely used methods for genetically modifying grasses. Here, these two systems are compared for transformation efficiency, transgene integration and transgene expression when used to transform tall fescue (Festuca arundinacea Schreb.). The bar gene was used as a selectable marker and selection during tissue culture was performed using 2 mg/l bialaphos in both callus induction and regeneration media. Average transformation efficiency across the four callus lines used in the experiments was 10.5% for Agrobacterium-mediated transformation and 11.5% for particle bombardment. Similar transgene integration patterns and co-integration frequencies of bar and uidA were observed in both gene transfer systems. However, while GUS activity was detected in leaves of 53% of the Agrobacterium transformed lines, only 20% of the bombarded lines showed GUS activity. Thus, Agrobacterium-mediated transformation appears to be the preferred method for producing transgenic tall fescue plants. PMID:18648817

Gao, Caixia; Long, Danfeng; Lenk, Ingo; Nielsen, Klaus Kristian

2008-10-01

232

Laser-induced breakdown spectroscopy used to detect endophyte-mediated accumulation of metals by tall fescue  

SciTech Connect

Laser-induced breakdown spectroscopy (LIBS) was used to determine the impact of endophyte (Neotyphodium sp.) infection on elemental composition of tall fescue (Festuca arundinacea). Leaf material from endophyte-infected (E+) and endophyte-free (E-) tall fescue populations in established plots was examined. Leaf-tissue digestates were also tested for metals, by inductively coupled plasma (ICP) mass spectrometry (MS). Seven of eleven metals (Ca, Mg, Fe, Mn, Cu, Ni, and Zn) were measured by both techniques at concentrations great enough for a reliable comparison. Mg, Zn, and Cd, a toxic metal that can be present in forage, were readily detected by LIBS, even though Cd concentrations in the plants were below levels typically achieved using ICP MS detection. Implications of these results for research on forage analysis and phytoremediation are discussed.

Martin, Madhavi Z.; Stewart, Arthur J.; Gwinn, Kimberley D.; Waller, John C.

2010-05-01

233

Breast tumor resembling the tall cell variant of papillary thyroid carcinoma: report of 4 cases with evidence of malignant potential.  

PubMed

A new type of breast carcinoma resembling the tall cell variant of papillary thyroid carcinoma has recently been described. To date, rare cases are on record. Here, 4 new cases of the tall cell variant of papillary thyroid carcinoma of the breast are described in women aged from 45 to 80 years old. All patients presented with palpable breast nodules and were treated with quadrantectomy. One patient presented with a long clinical history and a metastatic intramammary lymph node. The patient is alive and well 3 months after surgery. The remaining 3 patients are disease free at mean 7.5 months (range, 5 to 10 months) after surgery. These data suggest that papillary thyroid-like carcinomas of the breast show malignant potential. PMID:17172492

Tosi, Anna L; Ragazzi, Moira; Asioli, Sofia; Del Vecchio, Marina; Cavalieri, Monica; Eusebi, Leonardo H U; Foschini, Maria P

2007-01-01

234

Characteristics of upward lightning from a 325-m-tall meteorology tower  

NASA Astrophysics Data System (ADS)

Comprehensive observations of lightning flashes striking at a 325-m-tall meteorology tower were conducted in Beijing, China, during the summer of 2012. The images from high speed camera and normal video camera and the measurements of electric field changes were examined to investigate the characteristics of upward negative lightning initiated from the tower. Among eight upward lightning flashes documented during two thunderstorms, four were self-initiated events without lightning activity nearby prior to their initiation, two were triggered by the nearby positive cloud-to-ground lightning (+ CG) with the initiation of the upward leaders from the tower lagged 0.4 ms and 5 ms behind, respectively, and the remaining two were triggered by nearby intra-cloud lightning activities. The average 2-D speed of the upward positive leader was 1.0 × 105 m/s within several hundred meters above the tower tip. When the upward lightning occurred, the tower was swept by a radar echo zone with not very strong peak intensity of about 35-45 dBZ, which exhibited as a secondary convective area in the trailing stratiform region of the mesoscale convective system. The vertical cross section revealed a relatively low altitude of the radar echo center, indicative of a low charge center of the cloud which was favorable for initiating tower lightning.

Jiang, Rubin; Qie, Xiushu; Wu, Zhijun; Wang, Dongfang; Liu, Mingyuan; Lu, Gaopeng; Liu, Dongxia

2014-11-01

235

Gender effects of tall oil versus soybean phytosterols as cholesterol-lowering agents in hamsters.  

PubMed

To examine the effect of gender on the mechanisms of action of phytosterols extracted from tall oil (TO) and soybean (SB) on cholesterol and phytosterol metabolism, male and female hamsters were fed cholesterol-enriched diets containing 0.5 or 1% (w/w) TO or SB phytosterols for 90 days. Plasma lipoprotein cholesterol profile and tissue phytosterol and cholesterol biosynthesis levels were determined. Mean plasma total-cholesterol level in females fed 1% (w/w) SB was reduced (p<0.05) by 44%, while in males it was lowered (p<0.05) by 25% compared with their respective controls. Moreover, mean plasma total-cholesterol level was reduced (p<0.05) in male hamsters by -31% and female hamsters by -32% when fed 1% (w/w) TO. Cholesterol biosynthesis was higher (p<0.05) by twofold in groups fed TO at 0.5 and 1% (w/w) concentrations, compared with SB. Hamsters fed TO at 0.5 and 1% (w/w) levels also had higher (p<0.05) hepatic and enterocytic campesterol contents than SB-fed animals. These findings demonstrate gender differences in cholesterol metabolism in TO- and SB-fed hamsters. The results suggest that TO, conversely to SB phytosterol, is a more effective cholesterol-lowering agent in male, but not as much in female, hamsters, over a feeding period of 90 days. PMID:10030459

Ntanios, F Y; MacDougall, D E; Jones, P J

1998-01-01

236

Fabrication process for tall, sharp, hollow, high aspect ratio polymer microneedles on a platform  

NASA Astrophysics Data System (ADS)

This paper reports on a new lithographic process for fabricating arrays of tall, high aspect ratio (defined as height/wall thickness), hollow, polymer microneedles on a platform. The microneedles feature a high sharpness (down to 3 µm tip radius) and aspect ratio (>65) which is a factor 2 and 4 better than the state of the art, respectively. The maximum achievable needle shaft length is over 1 mm. The improved performance was obtained by using an anisotropically patterned silicon substrate covered with an antireflective layer as mold for the needle tip and an optimized SU-8 lithographic process. Furthermore, a platform containing liquid feedthroughs holding an arbitrary number of needles out of plane can be manufactured with only one additional process step. The high aspect ratio microneedles undergo failure at the critical load of around 230 mN in the case of 1 mm long hollow needles with triangular cross section and a base of 175 µm. Penetration into human skin is demonstrated as well.

Ceyssens, Frederik; Chaudhri, Buddhadev Paul; Van Hoof, Chris; Puers, Robert

2013-07-01

237

Tall fescue is a potential spillover reservoir host for Alternaria species.  

PubMed

The spread of invasive species is complicated and multifaceted. Enemy spillover (i.e. the transfer of a natural enemy from a reservoir host to a novel host) is one mechanism that facilitates the spread of non-native species. The reservoir host is a species that harbors high abundance of the enemy with little cost to fitness. We asked whether Schedonorus arundinaceus (tall fescue), a highly invasive grass species in North America, is a potential reservoir host for the ubiquitous genus of fungi, Alternaria. We also asked whether spillover of Alternaria is possible among grasses that commonly occur with S. arundinaceus in grassland ecosystems. We performed a greenhouse cross inoculation of three isolates of Alternaria and six grass species (three native, three invasive, including S. arundinaceus). We determined that spillover is possible because the fungal isolates infected and caused disease symptoms on all six grasses and decreased biomass in two of the grass species. We also determined that the invasive grass species appear to be more competent hosts than the native species and that S. arundinaceus could be a likely reservoir host for Alternaria spp. because it can harbor the pathogen with no apparent fitness cost. PMID:24603832

Wilson, Hannah E; Carroll, George C; Roy, Bitty A; Blaisdell, G Kai

2014-01-01

238

A tall-spined ornithopod dinosaur from the Early Cretaceous of Salas de los Infantes (Burgos, Spain)  

Microsoft Academic Search

A tall-spined ornithopod dinosaur from the Pinilla de los Moros Formation (Upper Hauterivian-Lower Barremian) of Salas de los Infantes (Burgos, Spain) is described. The material consists of seven associated axial remains, including five middle dorsal vertebrae, a fragmentary neural spine and a dorsal rib, from a single medium-sized individual. This material was previously referred to Iguanodon cf. fittoni. It is

Xabier Pereda-Suberbiola; José Ignacio Ruiz-Omeñaca; Fidel Torcida Fernández-Baldor; Michael W. Maisch; Pedro Huerta; Rubén Contreras; Luis Ángel Izquierdo; Diego Montero Huerta; Víctor Urién Montero; Jochen Welle

2011-01-01

239

Antitumor activity of a human cytotoxic T-cell line (TALL104) in brain tumor xenografts 1  

Microsoft Academic Search

Malignant glioma in adults and primitive neuroectoder- mal tumors\\/medulloblastomas in children are the most common malignant primary brain tumors that either respond poorly to current treatment or tend to recur. Adoptive therapy with TALL-104 cells—an IL-2-depen- dent, major histocompatibility complex nonrestricted, cytotoxic T-cell line—has demonstrated signiécant antitu- mor activity against a broad range of implanted or spon- taneously arising tumors.

Birgit Geoerger; Cheng-Bi Tang; Alessandra Cesano; Sophie Visonneau; Sunil Marwaha; Kevin D. Judy; Leslie N. Sutton; Daniela Santoli; Peter C. Phillips

240

Ant and plant-mediated indirect effects induced by aphid colonization on herbivorous insects on tall goldenrod  

Microsoft Academic Search

We studied the indirect effects of an aphid Uroleucon nigrotuberculatum on density and performance of herbivorous insects through tending ants and modification of plant traits on a tall goldenrod\\u000a Solidago altissima in Japan. To examine ant-mediated indirect effects of the aphid on the leafhopper and geometrid moth caterpillars, we conducted\\u000a an experiment in which we manipulated aphid densities. The aphid

Yoshino Ando; Takayuki Ohgushi

2008-01-01

241

Pseudomonas syringae pv. solidagae pv. nov., the Causal Agent of Bacterial Leaf Spot of Tall Goldenrod Solidago altissima L  

Microsoft Academic Search

  A new bacterial disease of tall goldenrod (Solidago altissima L., “Seitaka-awadachiso” in Japanese), one of the most serious weeds in non-agricultural land, was discovered in Ibaraki Prefecture,\\u000a Japan. Characterized by angular or round, dark brown necrotic spots on leaves, this disease resulted in defoliation and terminal\\u000a dieback of the plants in severe cases. The disease was named “bacterial leaf spot”.

Mamoru SATOl; Kenji WATANABE; Yoko SATO

2001-01-01

242

Tall Whitetop Eradication and Native Plant Community Restoration Shannon Peters, RTI and Ph.D. Candidate UC Berkeley, 360 Monte Vista Ave., Oakland, CA 94611  

E-print Network

(Lepidium latifolium) is a member of the mustard or Brassicaceae family. It is a native of southeastern and difficult to control or eradicate." Tall whitetop (Lepidium latifolium), (TWT), aka Perennial pepperweed

Bruns, Tom

243

A high rise multi-use building for Boston : an investigation into the nature and organization of public space in a tall building  

E-print Network

This thesis is essentially a study of how to organize public space vertically in a tall building. In most cases, high rise buildings tend to be organized in one of two ways, either centrally, with the core elements in the ...

Weiner, David Jay

1984-01-01

244

Effects of multiple climate change factors on the tall fescue-fungal endophyte symbiosis: infection frequency and tissue chemistry.  

SciTech Connect

Climate change (altered CO{sub 2}, warming, and precipitation) may affect plant-microbial interactions, such as the Lolium arundinaceum-Neotyphodium coenophialum symbiosis, to alter future ecosystem structure and function. To assess this possibility, tall fescue tillers were collected from an existing climate manipulation experiment in a constructed old-field community in Tennessee (USA). Endophyte infection frequency (EIF) was determined, and infected (E+) and uninfected (E-) tillers were analysed for tissue chemistry. The EIF of tall fescue was higher under elevated CO{sub 2} (91% infected) than with ambient CO{sub 2} (81%) but was not affected by warming or precipitation treatments. Within E+ tillers, elevated CO{sub 2} decreased alkaloid concentrations of both ergovaline and loline, by c. 30%; whereas warming increased loline concentrations 28% but had no effect on ergovaline. Independent of endophyte infection, elevated CO{sub 2} reduced concentrations of nitrogen, cellulose, hemicellulose, and lignin. These results suggest that elevated CO{sub 2}, more than changes in temperature or precipitation, may promote this grass-fungal symbiosis, leading to higher EIF in tall fescue in old-field communities. However, as all three climate factors are likely to change in the future, predicting the symbiotic response and resulting ecological consequences may be difficult and dependent on the specific atmospheric and climatic conditions encountered.

Brosi, Glade [University of Kentucky; McCulley, Rebecca L [University of Kentucky; Bush, L P [University of Kentucky; Nelson, Jim A [University of Kentucky; Classen, Aimee T [University of Tennessee, Knoxville (UTK); Norby, Richard J [ORNL

2011-01-01

245

Ascorbic acid enhances the accumulation of polycyclic aromatic hydrocarbons (PAHs) in roots of tall fescue (Festuca arundinacea Schreb.).  

PubMed

Plant contamination by polycyclic aromatic hydrocarbons (PAHs) is crucial to food safety and human health. Enzyme inhibitors are commonly utilized in agriculture to control plant metabolism of organic components. This study revealed that the enzyme inhibitor ascorbic acid (AA) significantly reduced the activities of peroxidase (POD) and polyphenol oxidase (PPO), thus enhancing the potential risks of PAH contamination in tall fescue (Festuca arundinacea Schreb.). POD and PPO enzymes in vitro effectively decomposed naphthalene (NAP), phenanthrene (PHE) and anthracene (ANT). The presence of AA reduced POD and PPO activities in plants, and thus was likely responsible for enhanced PAH accumulation in tall fescue. This conclusion is supported by the significantly enhanced uptake of PHE in plants in the presence of AA, and the positive correlation between enzyme inhibition efficiencies and the rates of metabolism of PHE in tall fescue roots. This study provides a new perspective, that the common application of enzyme inhibitors in agricultural production could increase the accumulation of organic contaminants in plants, hence enhancing risks to food safety and quality. PMID:23185628

Gao, Yanzheng; Li, Hui; Gong, Shuaishuai

2012-01-01

246

Influence of tall oil biodiesel with Mg and Mo based fuel additives on diesel engine performance and emission.  

PubMed

The purpose of this study is to investigate influences of tall oil biodiesel with Mg and Mo based fuel additives on diesel engine performance and emission. Tall oil resinic acids were reacted with MgO and MoO(2) stoichiometrically for the production of metal-based fuel additives (combustion catalysts). The metal-based additives were added into tall oil biodiesel (B60) at the rate of 4 micromol/l, 8 micromol/l and 12 micromol/l for preparing test fuels. In general, both of the metal-based additives improved flash point, pour point and viscosity of the biodiesel fuel, depending on the rate of additives. A single cylinder DI diesel engine was used in the tests. Engine performance values did not change significantly with biodiesel fuels, but exhaust emission profile was improved. CO emissions and smoke opacity decreased by 56.42% and by 30.43%, respectively. In general, low NO(x) and CO(2) emissions were measured with the biodiesel fuels. PMID:18164614

Keskin, Ali; Gürü, Metin; Altiparmak, Duran

2008-09-01

247

Ascorbic Acid Enhances the Accumulation of Polycyclic Aromatic Hydrocarbons (PAHs) in Roots of Tall Fescue (Festuca arundinacea Schreb.)  

PubMed Central

Plant contamination by polycyclic aromatic hydrocarbons (PAHs) is crucial to food safety and human health. Enzyme inhibitors are commonly utilized in agriculture to control plant metabolism of organic components. This study revealed that the enzyme inhibitor ascorbic acid (AA) significantly reduced the activities of peroxidase (POD) and polyphenol oxidase (PPO), thus enhancing the potential risks of PAH contamination in tall fescue (Festuca arundinacea Schreb.). POD and PPO enzymes in vitro effectively decomposed naphthalene (NAP), phenanthrene (PHE) and anthracene (ANT). The presence of AA reduced POD and PPO activities in plants, and thus was likely responsible for enhanced PAH accumulation in tall fescue. This conclusion is supported by the significantly enhanced uptake of PHE in plants in the presence of AA, and the positive correlation between enzyme inhibition efficiencies and the rates of metabolism of PHE in tall fescue roots. This study provides a new perspective, that the common application of enzyme inhibitors in agricultural production could increase the accumulation of organic contaminants in plants, hence enhancing risks to food safety and quality. PMID:23185628

Gao, Yanzheng; Li, Hui; Gong, Shuaishuai

2012-01-01

248

Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.  

PubMed

In order to investigation of allelopathic effects of some ornamental trees on seed germination of rye-grass (Lolium prenne) and tall fescue (Festuca arundinaceae), this experiment was conducted in a randomized complete block design with 3 replicates at the laboratory of Horticultural Sciences Department of Ferdowsi University of Mashhad, during 2008. In this research, we studied the effect of aqueous and hydro-alcoholic extracts of Afghanistan pine (Pinus eldarica), arizona cypress (Cupressus arizonica), black locust (Robinia psedue acacia) and box elder (Acer negundo) leaves that prepared in 1:5 ratio on seed germination percent and rate for two grasses. The results showed that all extracts decreased statistically seed germination in compared to control treatment. The highest germination percentage and germination rate of tested grass detected in control treatment. Hydro-alcoholic extracts of all woody plants (15, 30%) were completely inhibited seed germination of rye-grass and tall fescue. Also aqueous extract of arizona cypress was completely inhibited seed germination of tall fescue and had more inhibitory activity than other aqueous extracts on rye-grass. Between aqueous extracts, the highest and lowest seed germination of rye-grass was found in Afghanistan pine and arizona cypress, respectively. PMID:21313873

Arouiee, H; Nazdar, T; Mousavi, A

2010-11-01

249

Genetic analysis with nanoPCR.  

PubMed

Polymerase chain reaction (PCR) has become a standard and important molecular biological technique with numerous applications in genetic analysis, forensics and in vitro diagnostics. Since its invention in the 1980s, there has been dramatic performance improvement arising from long-lasting efforts to optimize amplification conditions in both academic studies and commercial applications. More recently, a range of nanometer-sized materials including metal nanoparticles, semiconductor quantum dots, carbon nanomaterials and polymer nanoparticles, have shown unique effects in tuning amplification processes of PCR. It is proposed that these artificial nanomaterials mimic protein components in the natural DNA replication machinery in vivo. These so-called nanomaterials-assisted PCR (nanoPCR) strategies shed new light on powerful PCR with unprecedented sensitivity, selectivity and extension rate. In this review, we aim to summarize recent progress in this direction and discuss possible mechanisms for such performance improvement and potential applications in genetic analysis (particularly gene typing and haplotyping) and diagnostics. PMID:22907590

Pan, Dun; Mi, Lijuan; Huang, Qing; Hu, Jun; Fan, Chunhai

2012-10-01

250

Nano-Dust Analyzer  

NASA Astrophysics Data System (ADS)

Recently, the STEREO WAVES instruments recorded a large number of intense electric field signals, which were interpreted as impacts from nanometer sized particles striking the spacecraft with velocities of about the solar wind speed [1]. This high flux and strong spatial and/or temporal variations of nanometer sized dust grains at low latitude appears to be uncorrelated with the solar wind properties. Early dust instruments onboard Pioneer 8 and 9 and Helios spacecraft detected a flow of submicron sized dust particles coming from the direction of the Sun. These particles originate in the inner solar system from mutual collisions among meteoroids and move on hyperbolic orbits that leave the Solar System under the prevailing radiation pressure force [2]. The observed fluxes of inner-source pickup ions also point to the existence of a much enhanced dust population in the nanometer size range [3]. A new highly sensitive instrument is being developed within NASA's Heliophysics Program to confirm the existence of the so-called nano-dust particles, characterize their impact parameters, and measure their chemical composition. The instrument is based on the Cassini Dust Analyzer (CDA) that has analyzed the composition of nanometer sized dust particles emanating from the Jovian and Saturnian systems but could not be pointed towards the Sun. By applying technologies implemented in solar wind instruments and coronagraphs a highly sensitive dust analyzer will be developed and tested in the laboratory. The measurements will enable us to identify the source of the dust by comparing their elemental composition with that of larger micrometeoroid particles of cometary and asteroid origin and will reveal interaction of nano-dust with the interplanetary medium by investigating the relation of the dust flux with solar wind and IMF properties. [1] Meyer-Vernet, N. et al., Solar Physics, 256, 463, 2009 [2] Zook, H.A. and Berg, O.E.: A source for hyperbolic cosmic dust particles. Planetary and Space Science, 23 (1975) 183-203. [3] Schwadron, N. A., et al., J. Geophys. Res., 105, 7465, 2000.

Gruen, E.; Horanyi, M.; Moebius, E.; Sternovsky, Z.; Auer, S.; Srama, R.; Juhasz, A.

2010-12-01

251

Continuous CO2/CH4 measurement at Zotino Tall Tower Observatory (ZOTTO) in Central Siberia  

NASA Astrophysics Data System (ADS)

Global climate change has particular impact on Siberia, where one tenth of global vegetation and soil carbon is stored. The increase in temperature lengthens the vegetation period and consequently enlarges the carbon sink. On the other hand, a warming climate will enhance thawing of permafrost which contains organic carbon that can be released either as carbon dioxide or methane depending on the local hydrological conditions. Long-term biogeochemical trace gas measurements on tall towers (> 250 m) over continents help to improve the knowledge about surface source/sink processes at regional to continental scales. Without the usage of aircrafts, the height of the tower allows regular probing of the mixed part of the boundary layer, which is - unlike the surface layer - only moderately influenced by diurnal variations of local surface fluxes and thus representative for a larger region (~1000km). The recently established Zotino Tall Tower Observatory (ZOTTO, 304 m, www.zottoproject.org) is located near the village of Zotino at the Yenisei River in central Siberia (60° N, 89° E). The ZOTTO facility was built in the perspective to monitor and determine variability and trends in the carbon balance of central Siberian forests. Since April 2009 we measure CO2 and CH4 from 6 height levels reaching from 4 to 301 m with an analyzer based on the cavity ring-down spectroscopy technique (Picarro Inc., CA, USA, model G1301). Experiments have shown that reliable accurate measurements can be obtained even without drying the sample gas. To obtain dry air mixing ratios for CO2 and CH4, the simultaneous water vapor measurements are used to correct dilution and pressure broadening effects, resulting in a precision and accuracy that is better than WMO recommendations. Furthermore, the system requires only a very low amount of calibration gases, because calibration takes place only every 100 hrs. These two aspects allow keeping maintenance low, which is an important requirement for this remote station. In each sampling line buffer volumes integrate the atmospheric signal over a typical time period of 40 minutes. With these the periodic switching from line to line every three minutes with only one single analyzer provides a quasi continuous, concurrent measurement from each height level. As a consequence of the averaging as well as the precision of the analyzer, the data show a low noise level and still moderately high temporal resolution, and gradients between different levels can be determined to a very high accuracy. The new data from 2009 and 2010 will be presented and interpreted in the context of regional sources and sinks of CO2 and CH4 in central Siberia. As the nocturnal boundary develops during night, it locally traps respired CO2 and CH4 and builds up vertical gradients. The analysis of the gradients allows estimating the trapped carbon amount in this layer which can be assigned to a certain region by using the Lagrangian transport model STILT.

Winderlich, Jan; Chen, Huilin; Höfer, Annette; Gerbig, Christoph; Panov, Alexey; Heimann, Martin

2010-05-01

252

3D nano-structures for laser nano-manipulation  

PubMed Central

Summary The resputtering of gold films from nano-holes defined in a sacrificial PMMA mask, which was made by electron beam lithography, was carried out with a dry plasma etching tool in order to form well-like structures with a high aspect ratio (height/width ? 3–4) at the rims of the nano-holes. The extraordinary transmission through the patterns of such nano-wells was investigated experimentally and numerically. By doing numerical simulations of 50-nm and 100-nm diameter polystyrene beads in water and air, we show the potential of such patterns for self-induced back-action (SIBA) trapping. The best trapping conditions were found to be a trapping force of 2 pN/W/?m2 (numerical result) exerted on a 50-nm diameter bead in water. The simulations were based on the analytical Lorentz force model. PMID:24062979

Seniutinas, Gediminas; Gervinskas, Gediminas; Brasselet, Etienne; Juodkazis, Saulius

2013-01-01

253

Nano-Biophotonics: new tools for chemical nano-analytics  

PubMed Central

Summary The nondestructive chemical analysis of biological processes in the crowded intracellular environment, at cellular membranes, and between cells with a spatial resolution well beyond the diffraction limit is made possible through Nano-Biophotonics. A number of sophisticated schemes employing nanoparticles, nano-apertures, or shaping of the probe volume in the far field have significantly extended our knowledge about lipid rafts, macromolecular complexes, i.e. chromatin, vesicles, and cellular organelles, and their interactions and trafficking within the cell. Here, I review some of the most recent developments in Nano-Biophotonics that already are or soon will become relevant to the analysis of intracellular processes. The pros and cons of the various techniques will be discussed and an outlook of their prospects for the near future will be provided. PMID:18786651

Huser, Thomas

2008-01-01

254

Measuring plant diversity in the tall threetip sagebrush steppe: influence of previous grazing management practices.  

PubMed

In July 2000, a 490-ha wildfire burned a portion of a long-term grazing study that had been established in 1924 at the US Sheep Experiment Station north of Dubois, Idaho, USA. Earlier vegetation measurements in this tall threetip sagebrush (Artemisia tripartita spp. tripartita) bunchgrass plant community documented significant changes in vegetation due to grazing and the timing of grazing by sheep. A study was initiated in May 2001 using 12 multiscale modified Whittaker plots to determine the consequences of previous grazing practices on postfire vegetation composition. Because there was only one wildfire and it did not burn all of the original plots, the treatments are not replicated in time or space. We reduce the potential effects of psuedoreplication by confining our discussion to the sample area only. There were a total of 84 species in the sampled areas with 69 in the spring-grazed area and 70 each in the fall- and ungrazed areas. Vegetation within plots was equally rich and even with similar numbers of abundant species. The spring-grazed plots, however, had half as much plant cover as the fall- and ungrazed plots and the spring-grazed plots had the largest proportion of plant cover composed of introduced (27%) and annual (34%) plants. The fall-grazed plots had the highest proportion of native perennial grasses (43%) and the lowest proportion of native annual forbs (1%). The ungrazed plots had the lowest proportion of introduced plants (4%) and the highest proportion of native perennial forbs (66%). The vegetation of spring-grazed plots is in a degraded condition for the environment and further degradation may continue, with or without continued grazing or some other disturbance. If ecosystem condition was based solely on plant diversity and only a count of species numbers was used to determine plant diversity, this research would have falsely concluded that grazing and timing of grazing did not impact the condition of the ecosystem. PMID:14753648

Seefeldt, Steven S; McCoy, Scott D

2003-08-01

255

Polyphenol oxidase activity in subcellular fractions of tall fescue contaminated by polycyclic aromatic hydrocarbons.  

PubMed

Understanding enzyme responses to contamination with persistent organic pollutants (POPs) is a key step in the elucidation of POP metabolic mechanisms in plants. However, there is little information available on enzyme activity in subcellular fractions of POP-contaminated plants. To our knowledge, this is the first study to investigate the activities of polyphenol oxidase (PPO) in cell fractions of plants under contamination stress from polycyclic aromatic hydrocarbons (PAHs) using a greenhouse batch technique. Three parameters, E(cell), E(cell-n), and P(cell), denoting the amount of PPO activity, cell fraction content-normalized PPO activity, and proportion of PPO activity in each cell fraction, respectively, were used in this study. Contamination with phenanthrene, as a representative PAH, at a relatively high level (>0.23 mg L?¹) in culture solution generally stimulated PPO activity in tall fescue (Festuca arundinacea Schreb.) roots and shoots and their cellular fractions. The amount and distribution proportion of PPO activity in each cell fraction of phenanthrene-contaminated roots and shoots were (in descending order): cell solution > > cell wall > cell organelles. Cell solution was the dominant storage domain of PPO activity and contributed 84.0 and 82.8% of PPO activity in roots and shoots, respectively. The cell wall had the highest density of PPO activity in roots and shoots, based on the highest cell fraction content normalized PPO activity in this cell fraction. Our results provide new information on enzyme responses in plant intracellular fractions to xenobiotic POPs and fundamental information on within-plant POP metabolic mechanisms. PMID:22565262

Ling, Wanting; Lu, Xiaodan; Gao, Yanzheng; Liu, Juan; Sun, Yandi

2012-01-01

256

"Tall oil"-derived phytosterols reduce atherosclerosis in ApoE-deficient mice.  

PubMed

We investigated the effects of a "tall oil"-derived phytosterol mixture (TODPM) on the formation of atherosclerotic lesions in apoE-deficient mice. TODPM was added at 2% (wt/wt) to the chow of nine mice; the control group had six animals. The diet of all animals contained 9% (wt/wt) fat and 0.15% (wt/wt) cholesterol. After 4 weeks, plasma total cholesterol levels were significantly reduced in the TODPM-treated mice (26.6 versus 42.0 mmol/L, P < .0001). The mean body weight of the TODPM-supplemented group was significantly higher at week 5 and throughout the study (29.4 versus 27.7 g, P < .05). The experiment was terminated at 18 weeks. Histological examination showed mature atherosclerotic lesions composed of foam cells underlying the endothelium, a mosaic of extracellular glycosaminoglycans, numerous apparently proliferative smooth muscle cells, and foci of cholesterol clefts in the control animals. By contrast, the TODPM-treated mice showed only early lesions containing mainly superficial foam cells. As assessed by morphometry, the lesion area in the aortic sinuses of TODPM-treated animals was less than half that of control animals (P < .0001). This reduced lesion area was accompanied by a substantial reduction in all lesional components, reflecting a delay in progression of atheromatous changes. A strong positive correlation (r = .69, P < .01) was found between plasma total cholesterol levels and lesion area in the aortic sinuses. TODPM also prevented the occurrence of xanthomatosis. We conclude that supplementation of a cholesterol-enriched diet with TODPM significantly lowers plasma cholesterol and retards development of atherosclerosis in apoE-deficient mice, suggesting a therapeutic potential for the mixture of phytosterols studied. PMID:9012646

Moghadasian, M H; McManus, B M; Pritchard, P H; Frohlich, J J

1997-01-01

257

Modern pollen-rain characteristics of tall terra firme moist evergreen forest, southern Amazonia  

NASA Astrophysics Data System (ADS)

The paucity of modern pollen-rain data from Amazonia constitutes a significant barrier to understanding the Late Quaternary vegetation history of this globally important tropical forest region. Here, we present the first modern pollen-rain data for tall terra firme moist evergreen Amazon forest, collected between 1999 and 2001 from artificial pollen traps within a 500 × 20 m permanent study plot (14°34'50?S, 60°49'48?W) in Noel Kempff Mercado National Park (NE Bolivia). Spearman's rank correlations were performed to assess the extent of spatial and inter-annual variability in the pollen rain, whilst statistically distinctive taxa were identified using Principal Components Analysis (PCA). Comparisons with the floristic and basal area data of the plot (stems ?10 cm d.b.h.) enabled the degree to which taxa are over/under-represented in the pollen rain to be assessed (using R-rel values). Moraceae/Urticaceae dominates the pollen rain (64% median abundance) and is also an important constituent of the vegetation, accounting for 16% of stems ?10 cm d.b.h. and ca. 11% of the total basal area. Other important pollen taxa are Arecaceae (cf. Euterpe), Melastomataceae/Combretaceae, Cecropia, Didymopanax, Celtis, and Alchornea. However, 75% of stems and 67% of the total basal area of the plot ?10 cm d.b.h. belong to species which are unidentified in the pollen rain, the most important of which are Phenakospermum guianensis (a banana-like herb) and the key canopy-emergent trees, Erisma uncinatum and Qualea paraensis.

Gosling, William D.; Mayle, Francis E.; Tate, Nicholas J.; Killeen, Timothy J.

2005-11-01

258

Nano Letters 8, 4477-4482 (2008) NANO-CRYSTALLOGRAPHY OF INDIVIDUAL CARBON NANOTUBES  

E-print Network

Nano Letters 8, 4477- 4482 (2008) 1 NANO-CRYSTALLOGRAPHY OF INDIVIDUAL CARBON NANOTUBES N. Bozovi 1 meV energy resolution and 1 nm spatial resolution.1 The later should enable nano-crystallography ­ XRD study of individual nano-particles. The commissioning of NSLS II will take some time -- the plan

Homes, Christopher C.

259

Nano-Tera.CH: Nano-technologies for Tera-scale Problems Giovanni De Micheli  

E-print Network

Nano-Tera.CH: Nano-technologies for Tera-scale Problems Giovanni De Micheli EPF Lausanne 1015, Switzerland ABSTRACT -- The Nano-Tera.CH initiative is a broad engineering program in Switzerland for health is rooted in advances in engineering nano-scale materials and their exploitation in a variety of systems

De Micheli, Giovanni

260

Whither `nano' or `bio'? | Rob Ritchie So what's all this hype about `nano' and `bio'?  

E-print Network

OPINION Whither `nano' or `bio'? | Rob Ritchie So what's all this hype about `nano' and `bio of these words. Indeed, I've heard numerous people glibly state that, unless the title of your proposal has `nano! The nano revolution has certainly taken our field by storm. One constantly hears of the new paradigm ­ we

Ritchie, Robert

261

Nano-engineered optical fibers and applications  

Microsoft Academic Search

This paper reviews a technology for making nano-engineered optical fibers. Key features and advantages of nano-enginneered glass fibers are discussed. Fiber designs and their applications are presented.

M.-J. Li; P. Tandon; D. Bookbinder; D. Nolan; S. Bickham; M. McDermott; R. Desorcie; J. Englebert; S. Logunov; V. Kozlov

2010-01-01

262

Synthesis of magnetic nano-composite particles  

Microsoft Academic Search

Carbon nano-particles were synthesized using an arc-discharge apparatus. Magnetic-metal filled nano-capsules were segregated from nonmagnetic carbon particles using a magnet. TEM, XRD, EDS and Raman scattering spectroscopic examination revealed that a magnetic iron particle, 10–50 nm in diameter, was encapsulated in each carbon nano-capsule. These magnetic-metal filled carbon nano-capsules were then coated individually with amorphous silicate to provide additional oxidation

C. P Chen; T. H Chang; T. F Wang

2002-01-01

263

From nano-hype to nano-nonsense, this issue in the  

E-print Network

BigPicture on From nano-hype to nano- nonsense, this issue in the Big Picture series sifts sense­13 What does the future hold for four nano-products? 14­15 The big picture 16 FIND OUT MORE ISSUE 2 JUNE and revolutionise medicine. They are the future, say the nano-enthusiasts. Hang on, say nano-sceptics, didn't you

Rambaut, Andrew

264

EE 337 Engineering micro and nano-systems EE 337 Engineering micro and nano-systems  

E-print Network

EE 337 Engineering micro and nano-systems Page 1 EE 337 Engineering micro and nano-systems A.edu/dept/engineering/eleceng/Adv_Network_Tech/Html/ee337.html This course is designed as an introduction to micro and nano-technology, methods to control and exploit the new degrees of freedom delivered by nano-science, and the integration of micro and nano

Levi, Anthony F. J.

265

EE 337 Engineering nano-systems EE 337 Engineering micro and nano-systems  

E-print Network

EE 337 Engineering nano-systems Page 1 EE 337 Engineering micro and nano-systems A.F.J. Levi Spring.edu/dept/engineering/eleceng/Adv_Network_Tech/Html/ee337.html This course is designed as an introduction to nano-technology, methods to control and exploit the new degrees of freedom delivered by nano-science, and the integration of nano-technology into systems

Levi, Anthony F. J.

266

The National Nanotechnology Initiative's nanoEHS Workshop Series: February 24-25, 2009: Human and Environmental Exposure Assessment of Nanomaterials  

E-print Network

The National Nanotechnology Initiative's nanoEHS Workshop Series: February 24-25, 2009: Human & Ethical, Legal, and Societal Implications of Nanotechnology National Nanotechnology Initiative Save in the National Nanotechnology Initiative's Strategy for Nanotechnology-related Environmental, Health, and Safety

267

Vacuum nano-hole array embedded organic light emitting diodes.  

PubMed

We demonstrated a nano-hole array (NHA) embedded structure that was fabricated for organic light emitting diodes (OLEDs) using a robust reverse transfer process. The NHA structure is proposed in this study as a strategy for maximizing the diffraction strength of two dimensional photonic crystals (PCs) by engineering vacuum nano-holes inside a dielectric slab. The electroluminescence (EL) intensity of the OLED was improved by more than twice. Such an optical enhancement was evaluated by using the angular dependence of photoluminescence (PL). The FDTD simulation was carried out to optimize the NHA structure for extraction of the emission induced from both vertical and horizontal dipoles. We explored the effect of the NHA structure on the extraction improvement converted from waveguide mode by measuring EL intensities of the devices with a hemisphere lens. In addition, the transfer process employed in this study yielded extremely low surface roughness, and thus outstanding electrical characteristics. PMID:24336917

Jeon, Sohee; Jeong, Jun-ho; Song, Young Seok; Jeong, Won-Ik; Kim, Jang-Joo; Youn, Jae Ryoun

2014-03-01

268

Nano-Power Africa Nano-Power Africa  

E-print Network

support of the American people through the United States Agency for International Development (USAID, USAID or the United States Government. August 24, 2010 #12;Nano-Power Africa iii Table.8 Annual Workshop 51 Section 5 Relationships to Stakeholders (from Strategic Plan) 52 5.1 USAID Mission

Beaucage, Gregory

269

Modification of esterified cell wall phenolics increases vulnerability of tall fescue to herbivory by the fall armyworm.  

PubMed

Feruloylation of arabinoxylan in grass cell walls leads to cross-linked xylans. Such cross-linking appears to play a role in plant resistance to pathogens and insect herbivores. In this study, we investigated the effect of ferulate cross-linking on resistance to herbivory by fall armyworm (Spodoptera frugiperda) making use of genetically modified tall fescue [Schedonorus arundinaceus (Festuca arundinacea)] expressing a ferulic acid esterase gene. Mature leaves of these plants have significant reduced levels of cell wall ferulates and diferulates but no change in acid detergent lignin. These reduced levels of esterified cell wall ferulates in transgenic plants had a positive effect on all measures of armyworm larval performance examined. More larvae survived (89 vs. 57 %) and grew faster (pupated 2.1 days sooner) when fed transgenic leaves with reduced levels of cell wall ferulates, than when fed control tall fescue leaves where levels of cell wall ferulates were not altered. Overall, mortality, growth and food utilization were negatively associated with level of esterified cell wall ferulates and diferulates in leaves they were fed. This study is the first to use transgenic plants with modified level of cell wall esterified ferulates to test the role of feruloylation in plant resistance to insects. It is concluded that the accumulation of ferulates and the cross-linking of arabinoxylans via diferulate esters in the leaves of tall fescue underlies the physical barrier to insect herbivory. Reducing ferulate cross-linking in grass cell walls could increase susceptibility of these plants to insect folivores. PMID:22434315

de O Buanafina, Marcia M; Fescemyer, Howard W

2012-08-01

270

Comparison of tall fescue (Cyperales: Gramineae) to other cool-season turfgrasses for tolerance to European chafer (Coleoptera: Scarabaeidae).  

PubMed

Three cultivars of tall fescue, Festuca arundinacea Schreb., were compared with three cultivars each of fine fescue (Festuca spp.), Kentucky bluegrass (Poa pratensis L.), and perennial ryegrass (Lolium perenne L.) to evaluate tolerance to root-feeding by European chafer grubs, Rhizotrogus majalis (Razoumowsky). Potted turfgrasses were infested with initial densities equivalent to 33 or 66 grubs per 0.1 m2 on 19 August 2000. More grubs were added in late September and October, bringing the total to 66 or 143 grubs per 0.1 m2. Plant growth, root loss, weight gain, and survival of grubs were measured. The experiment was repeated in fall of 2001 with an initial density of 66 grubs per 0.1 m2. The proportion of root mass lost as a result of grub feeding was a function of turf species, root growth, grub survival, and grub growth during the test. Grubs gained the most weight and consumed the most roots when feeding on fine fescue. Fine fescue suffered the greatest percentage of root loss in 2000, despite having the most rapid root growth and largest mass in control pots. Cultivars of tall fescue appeared to be the most tolerant of grub feeding, having the smallest reduction in root mass in both years. Data from fine fescue, Kentucky bluegrass, and perennial ryegrass cultivars were not as consistent as tall fescue, because for some cultivars root growth and grub survival were different between years. We also found that grubs increased in mass by 20% when the mass of available roots was doubled. PMID:14977131

Bughrara, Suleiman S; Smitley, David R; Cappaert, David; Kravchenko, A N

2003-12-01

271

A polymorphism in XKR4 is significantly associated with serum prolactin concentrations in beef cows grazing tall fescue.  

PubMed

Fescue toxicosis is a common syndrome of poor growth and reproductive performance of beef cattle grazing endophyte-infected tall fescue infected with Lolium arundinaceum Schreb. Together with decreased feed intake, decreased growth rates and tissue necrosis due to vasoconstriction, depressed circulating serum prolactin concentrations are typically observed in cattle afflicted with fescue toxicosis. Polymorphisms within the XK, Kell blood group complex subunit-related family, member 4 (XKR4) gene located on BTA14 have been previously reported to be associated with rump fat thickness, residual feed intake, average daily feed intake and average daily gain in cattle. Associations also have been reported between XKR4 genotype and effectiveness of the dopamine antagonist iloperidone as a treatment of schizophrenia in humans. Domperidone, a related dopamine antagonist, mediates effects of fescue toxicosis on livestock, including restoring depressed concentrations of prolactin. A mixed-breed population of 592 beef cattle grazing endophyte-infected tall fescue was used to examine the association between XKR4 genotype and circulating prolactin concentrations. The SNP rs42646708 was significantly (P = 0.0002) associated with serum prolactin concentrations and explained 2.45% of the phenotypic variation. Effect of genotype at the SNP was tested across five breeds, with significant associations within both Angus (P = 0.0275) and Simmental (P = 0.0224) breeds. These results suggest XKR4 may play a role in mediating the negative effects of fescue toxicosis, and polymorphisms within this gene may be useful markers for selection for genetic resistance to the debilitating effects of endophyte-infected tall fescue. PMID:24666329

Bastin, B C; Houser, A; Bagley, C P; Ely, K M; Payton, R R; Saxton, A M; Schrick, F N; Waller, J C; Kojima, C J

2014-06-01

272

Long-Term Measurements of Carbon Monoxide and Aerosols at the ZOTTO tall tower, Siberia  

NASA Astrophysics Data System (ADS)

The Zotino Tall Tower Observatory (ZOTTO), operated by the Max Planck Institutes for Biogeochemistry and Chemistry and the Institute of Forest (Krasnoyarsk), is located at 89.35°E, 60.80°N, 114 m asl. in Siberia, Russia. It centers on a 300-m tower designed for scientific measurements of chemical (trace gases, aerosol) and physical (meteorological) properties at a very remote, continental site. The instrumentation at the observatory comprises a CO Monitor, a Particle Soot Absorption Photometer (PSAP) for determining the aerosol absorption coefficient, a nephelometer for the determination of the aerosol scattering coefficient, and a Differential Mobility Particle Sizer (DMPS) to measure the aerosol number size distribution. We present measurements made from October 2006 until May 2008, with some interruptions due to technical reasons. An annual cycle of CO was observed with summer minima around 80 ppb and winter maxima of about 180 ppb. Amplitude and phase of the annual cycle were comparable to that reported by NOAA-ESRL for latitude 61°N. Periods of elevated CO concentrations, typically lasting for one to three days, interrupted the mean annual cycle. Backward trajectories computed with the NOAA HYSPLIT model indicated changes of air mass origin associated with the CO peaks. It was found, that for several peaks air masses have passed over the region of Novosibirsk - a heavily industrialized area. During summer, very sharp peaks of CO concentration with no change of air mass origin were observed. In this case, local wild fires are most likely the cause of the increase of CO concentrations. This general picture was confirmed by the output of the MATCH (Model of Atmospheric Transport and Chemistry) model that predicted CO concentrations in good agreement with the measured CO concentration at the ZOTTO site, resembling the typical annual cycle of CO concentrations. Furthermore, some of the peaks related to changes of the air mass origin were also predicted by the model, while the peaks presumably caused by wild fires were not found. The optical properties of the aerosol showed intense variations over the observation period. Episodes with strongly elevated absorption coefficients and particle concentrations occurred between periods of typical background readings. Using gaseous tracers, especially CO, and back-trajectories, these episodes could be traced to anthropogenic emission regions. The combination of CO concentration and aerosol properties with the determination of the air mass origin enables us to distinguish between continental background air and air masses being influenced by anthropogenic activities. Long-term variations in the continental background signal could give new insights into the feedback of ecosystems on a continental scale to changing climatic conditions.

Mayer, J. C.; Birmili, W.; Heimann, M.; Heintzenberg, J.; Juergens, N.; Kisilyakhov, Y.; Panov, A.; Andreae, M. O.

2009-12-01

273

Road pavers' occupational exposure to asphalt containing waste plastic and tall oil pitch.  

PubMed

Waste plastic (WP) and tall oil pitch (T), which are organic recycled industrial by-products, have been used as a binder with bitumen in stone mastic asphalt (SMA) and asphalt concrete (AC). We compared the exposure over one workday in 16 road pavers participating in a survey at four paving sites, using mixes of conventional asphalt (SMA, AC) or mixes containing waste material (SMA-WPT, AC-WPT). The concentrations of 11 aldehydes in air were 515 and 902 microg m(-3) at the SMA-WPT and AC-WPT worksites, being 3 and 13 times greater than at the corresponding worksites laying conventional asphalt. Resin acids (2-42 microg m(-3)), which are known sensitizers, were detected only during laying of AC-WPT. The emission levels (microg m(-3)) of total particulates (300-500), bitumen fumes (60-160), bitumen vapour (80-1120), naphthalene (0.59-1.2), phenanthrene (0.21-0.32), pyrene (<0.015-0.20), benzo(a)pyrene (<0.01) and the sum of 16 PAHs (polycyclic aromatic hydrocarbons, 1.28-2.00) were similar for conventional and WPT asphalts. The dermal deposition of 16 PAHs on exposure pads (on workers' wrist) was low in all pavers (0.7-3.5 ng cm(-2)). Eight OH-PAH biomarkers of naphthalene, phenanthrene and pyrene exposures were quantified in pre- and post-shift urine specimens. The post-shift concentrations (mean +/- SD, micromol mol(-1) creatinine) of 1- plus 2-naphthol; 1-,2-,3-,4- plus 9-phenanthrol; and 1-hydroxypyrene were, respectively, for asphalt workers: 18.1+/- 8.0, 2.41 +/- 0.71 and 0.66+/- 0.58 (smokers); 6.0+/- 2.3, 1.70+/- 0.72 and 0.27+/- 0.15 (non-smokers); WPT asphalt workers: 22.0+/- 9.2, 2.82+/- 1.11 and 0.76+/- 0.18 (smokers); 6.8+/- 2.6, 2.35+/- 0.69 and 0.46+/- 0.13 (non-smokers). The work-related uptake of PAHs was low in all pavers, although it was significantly greater in smokers than in non-smokers. The WPT asphalt workers complained of eye irritation and sore throat more than the pavers who had a much lower exposure to aldehydes and resin acids. PMID:16395464

Väänänen, Virpi; Elovaara, Eivor; Nykyri, Erkki; Santonen, Tiina; Heikkilä, Pirjo

2006-01-01

274

Long-Term Measurements of Carbon Monoxide and Aerosols at the ZOTTO tall tower, Siberia  

NASA Astrophysics Data System (ADS)

The Zotino Tall Tower Observatory (ZOTTO), operated by the Max Planck Institutes for Biogeochemistry and Chemistry and the Institute of Forest (Krasnoyarsk), is located at 89.35°E, 60.80°N, 114 m asl. at a very remote continental site in Siberia, Russia. It centers on a 300-m tower designed for scientific measurements of chemical (trace gases, aerosol) and physical (meteorological) properties. The instrumentation at the observatory includes a CO Monitor, a Particle Soot Absorption Photometer (PSAP) for determining the aerosol absorption coefficient, a nephelometer for the determination of the aerosol scattering coefficient, and a Differential Mobility Particle Sizer (DMPS) to measure the aerosol number size distribution. We present measurements made from October 2006 until March 2011, with some interruptions due to technical reasons. An annual cycle of the background CO mixing rations was observed with summer minima around 90 ppb and winter maxima of about 175 ppb. Amplitude and phase of the annual cycle were generally similar to that reported by NOAA-ESRL for latitude 61°N, but showed an earlier onset of the elevated winter values. Episodes of elevated CO and aerosol concentrations, typically lasting for several days, are superimposed on the background seasonal cycle. During winter, these pollution episodes are usually associated with air masses that have passed over the central Siberian region around Omsk and Novosibirsk - a heavily industrialized area. During spring and summer, elevated levels of CO and aerosols are often caused by agricultural fires in southern Siberia and Kazakhstan or by forest fires in boreal Siberia. The optical properties of the aerosol showed more pronounced seasonal variability than the aerosol mass and number concentrations. Wintertime aerosols were highly absorbing, with single scattering albedos (SSA) around 0.85, consistent with a dominant fossil fuel combustion source. In contrast, summertime aerosols had very low absorption coefficients with SSA values reaching 0.97. These aerosols were present in airmasses from northern Siberia with low CO mixing ratios, which suggests that they are predominantly of biogenic origin. The lowest particle number concentrations (averaging ~430 cm-3) were present in northern Siberian and Arctic airmasses, with similar values in summer and winter. Chemical analysis shows that sulfates and "black" carbon are elevated in the winter aerosol, while organic carbon from biomass burning and terpenoid oxidation dominate in summer. The measurements at ZOTTO are being continued, in the expectation that long-term variations in the continental background signal could give new insights into the feedback of ecosystems on a continental scale to changing climatic conditions.

Andreae, M. O.; Birmili, W.; Chi, X.; Heimann, M.; Heintzenberg, J.; Mikhailov, E.; Panov, A.

2012-04-01

275

Detection of a tall ridge at the core-mantle boundary from scattered PKP energy  

NASA Astrophysics Data System (ADS)

The seismic wavefield mainly contains reflected, refracted and direct waves but energy related to elastic scattering can also be identified at frequencies of 1 Hz and higher. The scattered, high-frequency seismic wavefield contains information on the small-scale structure of the Earth's crust, mantle and core. Due to the high thermal conductivity of mantle materials causing rapid dissipation of thermal anomalies, the Earth's small-scale structure most likely reveals details of the composition of the interior, and, is therefore essential for our understanding of the dynamics and evolution of the Earth. Using specific ray configurations we can identify scattered energy originating in the lower mantle and under certain circumstances locate its point of origin in the Earth allowing further insight into the structure of the lowermost mantle. Here we present evidence, from scattered PKP waves, for a heterogeneous structure at the core-mantle boundary (CMB) beneath southern Africa. The structure rises approximately 80 km above the CMB and is located at the eastern edge of the African LLSVP. Mining-related and tectonic seismic events in South Africa, with mb from 3.2 to 6.0 recorded at epicentral distances of 119.3° to 138.8° from Yellowknife Array (YKA) (Canada), show large amplitude precursors to PKPdf arriving 3-15 s prior to the main phase. We use array processing to measure slowness and backazimuth of the scattered energy and determine the scatterer location in the deep Earth. To improve the resolution of the slowness vector at the medium aperture YKA we present a new application of the F-statistic. The high-resolution slowness and backazimuth measurements indicate scattering from a structure up to 80 km tall at the CMB with lateral dimensions of at least 1200 km by 300 km, at the edge of the African Large Low Shear Velocity Province. The forward scattering nature of the PKP probe indicates that this is velocity-type scattering resulting primarily from changes in elastic parameters. The PKP scattering data are in agreement with dynamically supported dense material related to the Large Low Shear Velocity Province.

Frost, Daniel A.; Rost, Sebastian; Selby, Neil D.; Stuart, Graham W.

2013-10-01

276

Vasoconstriction in horses caused by endophyte-infected tall fescue seed is detected with Doppler ultrasonography.  

PubMed

The hypotheses that endophyte (Neotyphodium coenophialum)-infected tall fescue (TF) seed causes vasoconstriction in horses in vivo and that ground seed would cause more pronounced vasoconstriction than whole seed were tested. Ten horses each received 1 of 3 treatments: endophyte-free ground (E-G; n = 4 horses) seed, endophyte-positive whole (E+W; n = 3) seed, or endophyte-positive ground (E+G; n = 3) seed. There were two 14-d periods, P1 and P2. During P1, animals were adapted to a concentrate (0.2% BW, as fed, twice daily) and alfalfa cubes. During P2, the seed was mixed into the concentrate portion of the diet and alfalfa cubes were offered ad libitum. Fescue seed was fed in increasing amounts ranging from 0.02% BW on d 1 (averaging 76 ug/kg ergovaline + ergovalinine) to 0.22% BW on d 11 to 14 (averaging 713 ug/kg ergovaline + ergovalinine). The distal palmar artery of the left foreleg of each horse was scanned via Doppler ultrasonography for 4 d during each period, with 5 replicate scans performed on each scanning day. The measurements taken at each scan included artery luminal diameter, area, and circumference, peak systolic velocity, end diastolic velocity and blood flow variables. Animal temperature, heart rate, and respiration rate and ambient temperature and humidity were also recorded. Blood samples were taken on each scanning day to measure inflammatory cytokine mRNA abundances, and blood samples were collected on d 0, 4, 8, and 14 of P2 to measure prolactin concentrations. Consumption of E+G TF seed caused decreased artery lumen diameter (P = 0.0033), area (P = 0.0406), and circumference (P = 0.0480) compared with E-G seed, and E+W seed produced an intermediate response. Blood flow volume was reduced (P < 0.05) during P2 in horses receiving E+G seed compared with horses receiving E-G seed. Other ultrasound variables were not different (P > 0.05) among treatment groups, and neither were cytokine mRNA or prolactin concentrations. Treatment did not alter (P > 0.05) animal temperature, heart rate, or respiration rate, and neither ambient temperature nor relative humidity was consistently correlated with any response variable measured. Taken together, these data confirm that consumption of E+G fescue seed caused vasoconstriction in horses, which could be readily measured by Doppler ultrasonography. Use of Doppler ultrasound to monitor the diameter of the palmar artery of horses grazing endophyte-infected (E+) fescue pastures may provide a convenient and satisfactory biomarker to determine premonitory signs of fescue toxicosis. PMID:23449860

McDowell, K J; Moore, E S; Parks, A G; Bush, L P; Horohov, D W; Lawrence, L M

2013-04-01

277

Fescue-associated oedema of horses grazing on endophyte-inoculated tall fescue grass (Festuca arundinacea) pastures.  

PubMed

A new form of toxicity called equine fescue oedema is described. The clinical signs included inappetence, depression, and subcutaneous oedema of the head, neck, chest and abdomen. Affected horses had very low plasma albumin values. The toxicity affected 48 of 56 horses on six farms in different states of Australia, and 4 horses have died. All horses were grazing pastures that had been sown with varieties of Mediterranean tall fescue (Festuca arundinacea) that carry the endophyte known as Max P or Max Q. It is proposed that a pyrrolizidine alkaloid, N-acetyl norloline, which is produced by the Max P endophyte, may be responsible for this new toxicity in horses. PMID:19930166

Bourke, C A; Hunt, E; Watson, R

2009-12-01

278

Phenolic compounds, including novel C-glycosylflavone, from the flowers of the tall bearded iris cultivar 'Victoria Falls'.  

PubMed

A new C-glycosylflavone, luteolin 7-methyl ether 6-C-[beta-arabinopyranosyl-(1-2)-f-glucopyranoside] (swertiajaponin 2"-O-arabinoside) (1) was isolated and identified from the violet blue colored flowers of the tall bearded iris (Iris hybrid) cultivar 'Victoria Falls', together with five known flavonoids, swertisin 2"-O-arabinoside (2), schaftoside (3), isoschaftoside (4), swertiajaponin (5), swertisin 2"-O-glucoside (6) and a C-glycosylxanthone, mangiferin (7). Of these compounds, 1 and 2 were elucidated from NMR spectroscopic data, which revealed the rotameric pairs. C-Glycosylflavone O-arabinosides were isolated from the genus Iris for the first time. PMID:23413560

Mizuno, Takayuki; Yabuy, Tsutomu; Sasaki, Nobuhiro; Iwashina, Tsukasa

2012-12-01

279

Dimensional Micro and Nano Metrology  

Microsoft Academic Search

The need for dimensional micro and nano metrology is evident, and as critical dimensions are scaled down and geometrical complexity of objects is increased, the available technologies appear not sufficient. Major research and development efforts have to be undertaken in order to answer these challenges. The developments have to include new measuring principles and instrumentation, tolerancing rules and procedures as

H. N. Hansen; K. Carneiro; H. Haitjema; L. De Chiffre

2006-01-01

280

Realization and characterization of nano electromechanical devices based on ZnO nanowires  

Microsoft Academic Search

Realization techniques for integrating zinc oxide (ZnO) nanowire into micro electromechanical structures to form nano devices at low temperature are reviewed. Two main strategies are focused on: one is based on controllable dielectrophoretic assembly, and another is using electric-field assisted wet chemical growth. Functional properties of the fabricated devices including electrical contacts, photosensitivity, thermoelectricity, and piezoelectricity are summarized to demonstrate

Rong Zhu

2011-01-01

281

Responses of 2 epiphytic yeasts to foliar infection by Rhizoctonia solani or mechanical wounding on the phylloplane of tall fescue.  

PubMed

A growth-chamber experiment was conducted to determine how foliar disease or wounding affects the ability of 2 phylloplane yeasts (Rhodotorula glutinis and Cryptococcus laurentii) to colonize leaves of tall fescue (Festuca arundinacea). Yeasts were applied separately and together onto healthy leaves, leaves infected with Rhizoctonia solani (diseased), and mechanically bruised (wounded) leaves. In all 3 trials, the leaf disturbance treatment significantly affected the abundance of yeast on the phylloplane of tall fescue. Yeast abundance on the diseased or wounded leaves was significantly greater than on the nontreated, healthy leaves. In 2 of the 3 trials, the yeast species applied also had a significant affect on yeast abundance. Typically, R. glutinis was significantly more abundant than C. laurentii when applied individually, but not significantly greater than the total yeast colony-forming units of the co-inoculated treatment. When the 2 yeasts were co-inoculated onto the leaves, R. glutinis comprised 89.7%, 75.4%, and 67.6% of the recovered yeast colony-forming units on healthy, diseased, and wounded leaves, respectfully. Our data suggest that these 2 species of yeasts will differentially colonize compromised leaf tissue with disease or wounds favoring populations of R. glutinis over C. laurentii. PMID:19935888

Nix, Shannon; Burpee, Leon L; Buck, James W

2009-10-01

282

Ectopic overexpression of AtHDG11 in tall fescue resulted in enhanced tolerance to drought and salt stress.  

PubMed

Tall fescue (Festuca arundinacea Schreb.) is a cool-season perennial grass, which has been conventionally grown in the temperate area. However, as a major type of cool-season turf grass, its growth has been extended to the sub-tropical climate or even to the transitional climate between the sub-tropical and the tropical, and, in some cases, to heavily salinized lands. The extended growth imposes a serious challenge to its tolerance to the abiotic stress, particularly to drought, salt and high temperature. Here, we report a successful introduction of Arabidopsis AtHDG11 into the tall fescue via Agrobacterium-mediated transformation. The ectopic overexpression of AtHDG11 under the control of CaMV 35S promoter with four enhancers resulted in significantly enhanced tolerance to drought and salt stress. No obvious adverse effects on growth and development were observed in the transgenic plants. The enhanced stress tolerance was associated with a more extensive root system, a lower level of malondialdehyde, a nearly normal Na(+)/K(+) ratio, a higher level of proline and a kinetically accelerated induction of SOD and CAT activities observed in the transgenic plants during drought and/or salt stress, indicating that an enhanced ROS scavenging capability might play a significant role in the acquired tolerance to the abiotic stress. PMID:19132376

Cao, Ya-Jun; Wei, Qiang; Liao, Yang; Song, He-Ling; Li, Xian; Xiang, Cheng-Bin; Kuai, Ben-Ke

2009-04-01

283

The effect of a tall tower on flow and dispersion through a model urban neighborhood: part 1. Flow characteristics.  

PubMed

Wind tunnel experiments were performed to examine the effect of a tall tower on the flow around an otherwise uniform array of buildings. Additionally, preliminary CFD simulations were run to visualize the flow with more resolution. The model used in both the wind tunnel and CFD studies was designed to simulate an area of Brooklyn, NY, USA, where blocks of residential row houses form a neighborhood bordering a major urban highway. This area was the site of a field study that, along with the work reported here, had the goal of improving the understanding of airflow and dispersion patterns within urban microenvironments. Results reveal that a tall tower has a dramatic effect on the flow in the street canyons in the neighboring blocks, enhancing the exchange between the street canyon flow and the freestream flow aloft. In particular, vertical motion down the windward side and up the leeward side of the tower resulted in strong flows in the lateral street canyons and increased winds in the street canyons in the immediate vicinity of the tower. These phenomena were visible in both the wind tunnel and CFD results, although some minor differences in the flow fields were noted. PMID:20024013

Heist, David K; Brixey, Laurie A; Richmond-Bryant, Jennifer; Bowker, George E; Perry, Steven G; Wiener, Russell W

2009-12-01

284

Endophyte infection of tall fescue and the impact of climatic factors on ergovaline concentrations in field crops cultivated in southern france.  

PubMed

Tall fescue (Lolium arundinaceum) infected by Epichloe coenophiala contains ergot alkaloids responsible for fescue toxicosis in Australia, New Zealand, and the United States, with only a few cases occurring in Europe. The detection of Epichloe in 166 L. arundinaceum collected in southern France revealed that 60% were infected, 51% being high ergovaline producers. The ergovaline level in endophyte-infected tall fescue Kentucky 31 was monitored during 3 years in various parts of the plant. Maturation of plants, recorded according to the BBCH scale, appeared to be the main factor for estimating the risk of toxicity. Ergovaline levels of ?300 ?g/kg dry matter were obtained at the end of spring, the beginning of autumn, and mid-winter. Positive correlation between ergovaline level and cumulative degree-d was observed, whereas rainfall had no effect. These results suggest that the lack of fescue toxicosis observed in France cannot be explained by the lack of ergovaline in tall fescue. PMID:25192465

Repussard, Céline; Zbib, Nasrallah; Tardieu, Didier; Guerre, Philippe

2014-10-01

285

Pyroelectric nano-rods grown inside alumina nano-pores  

NASA Astrophysics Data System (ADS)

This paper reports the formation and properties of nano-composite pyroelectric thin films. They consist of pyroelectric triglycine sulfate (TGS) single-crystal nano-rods grown inside a highly dense array of alumina pores (about 65 nm diameter and density of 1011 cm -2). The nucleation and growth of the TGS single crystals are obtained by precipitation from a supersaturated aqueous solution. Nucleation is preferred only at the bottom of the pores due to a tight control of temperature, composition and pore diameter. Growth of single crystals with preferred crystallographic orientation is obtained with the aid of an applied electric field. Various crystallographic orientations (1 0 0) (-1 1 0) (-1 2 0) are obtained separately as a single preferred orientation by changing the amplitude of the electric field during crystal growth. The films exhibit ferroelectric behavior.

Nitzani, M.; Berger, S.

2007-03-01

286

RI&E Nano particles*) Carried out by  

E-print Network

1 RI&E Nano particles*) Carried out by: Faculty: CTW/EWI/TNW Department: 1. Information Nano characteristics of nano material (or parent material) **) Carcinogenic Mutagenic Reprotoxic Density (kg/dm3 ) kg/dm3 State of aggregation of the nano material Liquid Solid 2. Health hazard nano material Danger

Twente, Universiteit

287

Male-sterile and cleistogamous phenotypes in tall fescue induced by chimeric repressors of SUPERWOMAN1 and OsMADS58.  

PubMed

Since tall fescue (Festuca arundinacea Schreb.) is an anemophilous (wind-pollinated) grass species, male sterility is strongly desired for transgenic tall fescue to prevent pollen dispersal. To create male-sterile tall fescue, we applied Chimeric REpressor gene-Silencing Technology (CRES-T) based on rice APETALA3 (AP3) and AGAMOUS (AG) orthologues that specify the formation of stamens. We fused the coding regions of rice AP3 orthologue SUPERWOMAN1 (SPW1), and rice AG orthologues, Os12g0207000, Os01g0886200 and OsMADS58, respectively with the artificial sequence encoding the modified EAR-like motif repression domain (SRDX). We first introduced Os12g0207000SRDX, Os01g0886200SRDX and OsMADS58SRDX into rice for evaluation of their abilities to induce male sterility. The transgenic rice expressing OsMADS58SRDX had reiterated formation of lodicule-like organs instead of stamens and carpel, a typical phenotype of ag mutant. Thus, we found that OsMADS58SRDX was most suitable for our purpose. Next, we introduced SPW1SRDX and OsMADS58SRDX into tall fescue. Although the transgenic tall fescue did not have the stamen alterations seen in SPW1SRDX and OsMADS58SRDX rice, they either produced no pollen or produced immature pollen; thus, the anthers were not dehiscent and the plants were male-sterile. In addition to the male sterility, SPW1SRDX tall fescue showed a cleistogamous (closed) phenotype in which anthers were not observed outside the glumes, with thin, abnormally elongated lodicules. Some lines of OsMADS58SRDX tall fescue showed a cleistogamous phenotype in which the lodicules were homeotically transformed into lemma-like organs. In both cases, cleistogamous phenotype was associated with morphological changes to the lodicules. We also obtained a mild phenotype of OsMADS58SRDX tall fescue, which exhibited only the male sterility. In this study, we produced novel male-sterile phenotypes using chimeric repressors and thus suggest CRES-T as a tool for transgenic improvement of forage and turf grasses. PMID:22195592

Sato, Hiroko; Yoshida, Kouki; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Takamizo, Tadashi

2012-02-01

288

Metallic nano-particles for trapping light  

PubMed Central

We study metallic nano-particles for light trapping by investigating the optical absorption efficiency of the hydrogenated amorphous silicon thin film with and without metallic nano-particles on its top. The size and shape of these nano-particles are investigated as to their roles of light trapping: scattering light to the absorption medium and converting light to surface plasmons. The optical absorption enhancement in the red light region (e.g., 650nm) due to the light trapping of the metallic nano-particles is observed when a layer of metallic nano-particle array has certain structures. The investigation of the light with incident angles shows the importance of the coupling efficiency of light to surface plasmons in the metallic nano-particle light trapping. PACS 73.20.Mf, 42.25.s, 88.40.hj PMID:23391493

2013-01-01

289

Carbon Nano Tube (CNT) Circuits  

Microsoft Academic Search

Novel two types of Carbon Nano Tube (CNT)-based multiplexers are introduced. The first device is a solid- state transmission gate (t-gate) multiplexer that uses CNT as a channel in the Field Effect Transistors (FET) of both n-FET and p-FET types that are used. Because of its very small size, it has been shown that a CNT-based FET switches reliably using

Anas N. Al-Rabadi

290

3-D nano-fiber manufacturing by controlled pulling of liquid polymers using nano-probes  

Microsoft Academic Search

In-addition to the applications of imaging and characterization, proximal probes are proposed to be used three-dimensional (3-D) nano-scale manufacturing tools in this paper. Commercially available Atomic Force Microscope (AFM) systems are mainly limited to 1-D or 2-D manipulation tasks, and advanced 3-D nano-manufacturing applications are not possible. Therefore, this paper proposes 3-D nano-scale manipulation of liquid polymer nano-fibers by using

Amrinder S. Naint; Metin Sittit

2003-01-01

291

Nano-networks have better adsorption capability than nano-rods  

Microsoft Academic Search

Ion beam bombardment, as a unique and facile technique, was found and developed to fabricate nano-networks from rigid nano-rods. To study the differences of their characteristics, attapulgite (ATP) was chosen as a model. The results of methylene blue adsorption performance investigation demonstrated that attapulgite nano-networks (ATP-N) have better adsorption capability than the attapulgite nano-rods (ATP-R). The mechanism proposed that, compared

Dongqing Cai; Hong Zhang; Yi Tang; Paul K. Chu; Zengliang Yu; Zhengyan Wu

2010-01-01

292

Nano Lect 1 Questions and Keypoints Key Points  

E-print Network

Nano Lect 1 ­ Questions and Keypoints Key Points 1. What is nano technology: a. Very small technology with device in the 1nm to 100nm lots of useful properties Questions 1. Define nanotechnology. Is an nano

Smy, Tom

293

Nano for Business 2014: Partnering for Regional Success Our Fifth Nano for Business Conference!  

E-print Network

Nano for Business 2014: Partnering for Regional Success Our Fifth Nano for Business Conference! Thursday, May 22, 2014 from 8:30-4:30 Lehigh University, Rauch Business Center Agenda: http://www.lehigh.edu/lnn/docs/Nano_for_Business CAMN members, Drexel faculty Meet business and university contacts and learn about: · Nanotechnology

Gilchrist, James F.

294

Dynamics and Kinematics of Viral Protein Linear Nano-Actuators for Bio-Nano Robotic Systems  

E-print Network

Dynamics and Kinematics of Viral Protein Linear Nano- Actuators for Bio-Nano Robotic Systems A- lecular Kinematics; Molecular Motors. I. INTRODUCTION The recent explosion of research in nano machines and ro- bots. The main goal in the field of biomolecular machines is to use various biological

Mavroidis, Constantinos

295

Atmospheric Stability Impacts on Power Curves of Tall Wind Turbines - An Analysis of a West Coast North American Wind Farm  

SciTech Connect

Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow and turbulence at these heights in the boundary layer. Depending on whether the boundary layer is stable, neutral, or convective, the mean wind speed, direction, and turbulence properties may vary greatly across the tall turbine swept area (40 to 120 m AGL). This variability can cause tall turbines to produce difference amounts of power during time periods with identical hub height wind speeds. Using meteorological and power generation data from a West Coast North American wind farm over a one-year period, our study synthesizes standard wind park observations, such as wind speed from turbine nacelles and sparse meteorological tower observations, with high-resolution profiles of wind speed and turbulence from a remote sensing platform, to quantify the impact of atmospheric stability on power output. We first compare approaches to defining atmospheric stability. The standard, limited, wind farm operations enable the calculation only of a wind shear exponent ({alpha}) or turbulence intensity (I{sub U}) from cup anemometers, while the presence at this wind farm of a SODAR enables the direct observation of turbulent kinetic energy (TKE) throughout the turbine rotor disk. Additionally, a nearby research meteorological station provided observations of the Obukhov length, L, a direct measure of atmospheric stability. In general, the stability parameters {alpha}, I{sub U}, and TKE are in high agreement with the more physically-robust L, with TKE exhibiting the best agreement with L. Using these metrics, data periods are segregated by stability class to investigate power performance dependencies. Power output at this wind farm is highly correlated with atmospheric stability during the spring and summer months, while atmospheric stability exerts little impact on power output during the winter and autumn periods. During the spring and summer seasons, power output for a given wind speed was significantly higher during stable conditions and significantly lower during strongly convective conditions: power output differences approached 20% between stable and convective regimes. The dependency of stability on power output was apparent only when both turbulence and the shape of the wind speed profile were considered. Turbulence is one of the mechanisms by which atmospheric stability affects a turbine's power curve at this particular site, and measurements of turbulence can yield actionable insights into wind turbine behavior.

Wharton, S; Lundquist, J K

2010-02-22

296

Cellular-Level Surgery Using Nano Robots  

PubMed Central

The atomic force microscope (AFM) is a popular instrument for studying the nano world. AFM is naturally suitable for imaging living samples and measuring mechanical properties. In this article, we propose a new concept of an AFM-based nano robot that can be applied for cellular-level surgery on living samples. The nano robot has multiple functions of imaging, manipulation, characterizing mechanical properties, and tracking. In addition, the technique of tip functionalization allows the nano robot the ability for precisely delivering a drug locally. Therefore, the nano robot can be used for conducting complicated nano surgery on living samples, such as cells and bacteria. Moreover, to provide a user-friendly interface, the software in this nano robot provides a “videolized” visual feedback for monitoring the dynamic changes on the sample surface. Both the operation of nano surgery and observation of the surgery results can be simultaneously achieved. This nano robot can be easily integrated with extra modules that have the potential applications of characterizing other properties of samples such as local conductance and capacitance. PMID:23015517

Song, Bo; Yang, Ruiguo; Xi, Ning; Patterson, Kevin Charles; Qu, Chengeng; Lai, King Wai Chiu

2014-01-01

297

Broadband monopole optical nano-antennas  

NASA Astrophysics Data System (ADS)

In this paper, a novel design of broadband monopole optical nano-antennas is proposed. It consists of a corrugated halfelliptical patch inside an elliptical aperture. Full-wave electromagnetic simulations have been used to investigate the performance of the nano-antenna. The predicted performance of the proposed monopole nano-antenna is remarkably broadband. Moreover, the proposed broadband nano-antenna can respond to light waves with different polarizations. The proposed optical antenna will pave the way towards the development of high performance optical antennas and optical systems.

Zhou, Rongguo; Ding, Jun; Arigong, Bayaner; Lin, Yuankun; Zhang, Hualiang

2014-03-01

298

Nanoindentation response of piezoelectric nano-islands  

NASA Astrophysics Data System (ADS)

Through three-dimensional finite element modeling, it is demonstrated that the nanoindentation response of piezoelectric nano-islands is strongly dependent on the shape of the nano-island and the depth of indentation. For indentations that are relatively deep (i.e., greater than 5% of the height of the islands), the substrate's elastic and plastic properties have a strong influence on the indentation response of piezoelectric nano-islands with substrate plasticity resulting in a significant reduction in the mechanical and electrical indentation stiffness. The predictions of the finite element models compare well with experiments on nano-islands of strontium-doped lead zirconate titanate.

Cheng, Guang; Sriram, Sharath; Bhaskaran, Madhu; Venkatesh, T. A.

2014-09-01

299

Cellular-level surgery using nano robots.  

PubMed

The atomic force microscope (AFM) is a popular instrument for studying the nano world. AFM is naturally suitable for imaging living samples and measuring mechanical properties. In this article, we propose a new concept of an AFM-based nano robot that can be applied for cellular-level surgery on living samples. The nano robot has multiple functions of imaging, manipulation, characterizing mechanical properties, and tracking. In addition, the technique of tip functionalization allows the nano robot the ability for precisely delivering a drug locally. Therefore, the nano robot can be used for conducting complicated nano surgery on living samples, such as cells and bacteria. Moreover, to provide a user-friendly interface, the software in this nano robot provides a "videolized" visual feedback for monitoring the dynamic changes on the sample surface. Both the operation of nano surgery and observation of the surgery results can be simultaneously achieved. This nano robot can be easily integrated with extra modules that have the potential applications of characterizing other properties of samples such as local conductance and capacitance. PMID:23015517

Song, Bo; Yang, Ruiguo; Xi, Ning; Patterson, Kevin Charles; Qu, Chengeng; Lai, King Wai Chiu

2012-12-01

300

Development, analysis and design of a 292 ft tall self-erecting flare tower for offshore application  

SciTech Connect

This paper describes the development of a 292 ft tall flare tower applicable for large offshore production facilities. First of its kind in a flare tower design, an innovative but well proven self-erecting technique is used. The technique aimed eliminating the transportation and erection costs. The structural concept is known as Self-Erecting Flare Tower (SEFT). In SEFT concept, the tower is segmented into a number of small manageable sections. A jacket type bottom section is used to support telescoping the tower sections. The design erection procedure, technical and functional feasibility of SEFT concept are discussed. At the end of this paper, a cost comparison study with conventional flare tower is given.

Desai, V.; Srinivasan, N. [Dreco, Houston, TX (United States)

1995-12-31

301

A novel homozygous mutation in FGFR3 causes tall stature, severe lateral tibial deviation, scoliosis, hearing impairment, camptodactyly, and arachnodactyly.  

PubMed

Most reported mutations in the FGFR3 gene are dominant activating mutations that cause a variety of short-limbed bone dysplasias including achondroplasia and syndromic craniosynostosis. We report the phenotype and underlying molecular abnormality in two brothers, born to first cousin parents. The clinical picture is characterized by tall stature and severe skeletal abnormalities leading to inability to walk, with camptodactyly, arachnodactyly, and scoliosis. Whole exome sequencing revealed a homozygous novel missense mutation in the FGFR3 gene in exon 12 (NM_000142.4:c.1637C>A: p.(Thr546Lys)). The variant is found in the kinase domain of the protein and is predicted to be pathogenic. It is located near a known hotspot for hypochondroplasia. This is the first report of a homozygous loss-of-function mutation in FGFR3 in human that results in a skeletal overgrowth syndrome. PMID:24864036

Makrythanasis, Periklis; Temtamy, Samia; Aglan, Mona S; Otaify, Ghada A; Hamamy, Hanan; Antonarakis, Stylianos E

2014-08-01

302

Enhanced tolerance of transgenic tall fescue plants overexpressing 2-Cys peroxiredoxin against methyl viologen and heat stresses.  

PubMed

Plant 2-Cys peroxiredoxins (2-Cys Prx) has both peroxidase and chaperon function. We overexpressed an Arabidopsis 2-Cys Prx in transgenic tall fescue (Festuca arundinacea) plants to confer tolerance against heat and methyl viologen (MV) stress. Transgenic plants were generated by Agrobacterium-mediated genetic transformation, and integration and expression of the transgene was confirmed by Southern, northern and western blot analyses. Compared to control plants, transgenic plants had significantly less electrolyte leakage and thiobarbituric acid-reactive substances (TBARS) when exposed to heat or MV. Under heat stress (42 degrees C), transgenic plants maintained their chlorophyll fluorescence (Fv/Fm) for 24 h while control plants lost chlorophyll fluorescence very quickly. We conclude that the high levels of 2-Cys Prx proteins in transgenic plants protect leaves from oxidative damage probably due to chaperon activity. PMID:20013299

Kim, Kyung-Hee; Alam, Iftekhar; Lee, Ki-Won; Sharmin, Shamima Akhtar; Kwak, Sang-Soo; Lee, Sang Yeol; Lee, Byung-Hyun

2010-04-01

303

Removing traffic emissions from CO2 time series measured at a tall tower using mobile measurements and transport modeling  

NASA Astrophysics Data System (ADS)

In recent years, measurements of atmospheric carbon dioxide with high precision and accuracy have become increasingly important for climate change research, in particular to inform terrestrial biosphere models. Anthropogenic carbon dioxide emissions from fossil fuel burning have long been recognized to contribute a significant portion of the carbon dioxide in the atmosphere. Here, we present an approach to remove the traffic related carbon dioxide emissions from mole fractions measured at a tall tower by using the corresponding carbon monoxide measurements in combination with footprint analyses and transport modeling. This technique improves the suitability of the CO2 data to be used in inverse modeling approaches of atmosphere-biosphere exchange that do not account for non-biotic portions of CO2. In our study region in Oregon, road traffic emissions are the biggest source of anthropogenic carbon dioxide and carbon monoxide. A three-day mobile campaign covering 1700 km of roads in northwestern Oregon was performed during summer of 2012 using a laser-based Cavity Ring-Down Spectrometer. The mobile measurements incorporated different roads including main highways, urban streets, and back-roads, largely within the typical footprint of a tall CO/CO2 observation tower in Oregon's Willamette Valley. For the first time, traffic related CO:CO2 emission ratios were measured directly at the sources during an on-road campaign under a variety of different driving conditions. An average emission ratio of 7.43 (±1.80) ppb CO per ppm CO2 was obtained for the study region and applied to separate the traffic related portion of CO2 from the mole fraction time series. The road traffic related portion of the CO2 mole fractions measured at the tower site reached maximum values ranging from 9.8 to 12 ppm, depending on the height above the surface, during summer 2012.

Schmidt, Andres; Rella, Chris W.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Law, Beverly E.

2014-11-01

304

The skin compatibility of distilled tall oils: evaluation with the bovine udder skin in vitro model system.  

PubMed

Distilled tall oil (DTO) is a natural product, often added as an emulsifying ingredient in cutting fluids used as lubricants and coolants in metal working. The in vitro model used to test the skin compatibility of these substances, was the isolated perfused ex vivo bovine udder skin (BUS) model. After three exposure periods (0.5, 1, and 5 hours), cytotoxic effects were determined by using the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and tissue levels of the pre-inflammatory mediator prostaglandin E2 (PGE2) in treated whole skin biopsies were assessed by using an enzyme immunoassay. The BUS standard study design, involving a single application, was previously developed to investigate the skin irritation potential of cosmetics and chemicals. In the current study, four different batches of undiluted DTO, and tall oil fatty acids as a reference compound, were applied both singly and repeatedly (three times), under open conditions which were in line with the potential usage conditions in the work place. Under the standardised single application conditions, no major differences in cytotoxic effects or PGE2 levels between the samples were apparent, so no indication of a skin irritation potential could be concluded. This result is in accordance with prior in vivo studies for acute dermal toxicity. Under repeated application conditions, signs of cytotoxicity were observed after the application of one of the DTO samples, which was known to be derived from different raw materials. Therefore, it was concluded that, generally, the presence of DTO at a concentration of up to 10% in cutting fluids, is not expected to result in any DTO-related deterioration of the skin. PMID:19292577

Pittermann, Wolfgang; Hopfgarten, Fredrik; Kietzmann, Manfred

2009-02-01

305

Dependence of Wind Turbine Curves on Atmospheric Stability Regimes - An Analysis of a West Coast North American Tall Wind Farm  

SciTech Connect

Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow in the boundary layer. Depending on whether the boundary layer is stable, convective or neutral, mean wind speed (U) and turbulence ({sigma}{sub U}) may vary greatly across the tall turbine swept area (40 m to 120 m). This variation can cause a single turbine to produce difference amounts of power during time periods of identical hub height wind speeds. The study examines the influence that atmospheric mixing or stability has on power output at a West Coast North American wind farm. They first examine the accuracy and applicability of two, relatively simple stability parameters, the wind shear-exponent, {alpha}, and the turbulence intensity, I{sub u}, against the physically-based, Obukhov length, L, to describe the wind speed and turbulence profiles in the rotor area. In general, the on-site stability parameters {alpha} and I{sub u} are in high agreement with the off-site, L stability scale parameter. Next, they divide the measurement period into five stability classes (strongly stable, stable, neutral, convective, and strongly convective) to discern stability-effects on power output. When only the mean wind speed profile is taken into account, the dependency of power output on boundary layer stability is only subtly apparent. When turbulence intensity I{sub u} is considered, the power generated for a given wind speed is twenty percent higher during strongly stable conditions than during strongly convective conditions as observed in the spring and summer seasons at this North American wind farm.

Wharton, S; Lundquist, J K; Sharp, J; Zulauf, M

2009-08-24

306

Secondary Cell Wall Deposition Causes Radial Growth of Fibre Cells in the Maturation Zone of Elongating Tall Fescue Leaf Blades  

PubMed Central

A gradient of development consisting of successive zones of cell division, cell elongation and cell maturation occurs along the longitudinal axis of elongating leaf blades of tall fescue (Festuca arundinacea Schreb.), a C3 grass. An increase in specific leaf weight (SLW; dry weight per unit leaf area) in the maturation region has been hypothesized to result from deposition of secondary cell walls in structural tissues. Our objective was to measure the transverse cell wall area (CWA) associated with the increase in SLW, which occurs following the cessation of leaf blade elongation at about 25 mm distal to the ligule. Digital image analysis of transverse sections at 5, 15, 45, 75 and 105 mm distal to the ligule was used to determine cell number, cell area and protoplast area of structural tissues, namely fibre bundles, mestome sheaths and xylem vessel elements, along the developmental gradient. Cell diameter, protoplast diameter and area, and cell wall thickness and area of fibre bundle cells were calculated from these data. CWA of structural tissues increased in sections up to 75 mm distal to the ligule, confirming the role of cell wall deposition in the increase in SLW (r2 = 0·924; P ? 0·01). However, protoplast diameter of fibre cells did not decrease significantly as CWA increased, although mean thickness of fibre cell walls increased by 95 % between 15 and 105 mm distal to the ligule. Therefore, secondary cell wall deposition in fibre bundles of tall fescue leaf blades resulted in continued radial expansion of fibre cells rather than in a decrease in protoplast diameter. PMID:12096823

MACADAM, JENNIFER W.; NELSON, CURTIS J.

2002-01-01

307

Herodotus on Diet and Longevity: How the Persians Fed on Dung and Lived to 80, While the Tall, Handsome Ethiopians Ate Boiled Meat and Lived Beyond 120  

Microsoft Academic Search

Herodotus' Histories tell of diet and longevity: the Persians, who ate bread from grain fertilized with dung lived but 80 years, while the tall handsome Ethiopeans ate boiled meat and lived more than 120. These and other ancient texts anticipate current biomedical understanding of aging. However, there little evidence for supracentenarians in the ancient world as noted in Herodotus, Genesis,

Caleb E. Finch

2009-01-01

308

PERFORMANCE OF LAMBS ON PERENNIAL RYEGRASS, SMOOTH BROMEGRASS, ORCHARDGRASS AND TALL FESCUE PASTURE I. LIVE WEIGHT CHANGES, DIGESTIBILITY AND INTAKE OF HERBAGE 1,2  

Microsoft Academic Search

SUMMARY Grazing and feeding trials were conducted in 2 years to determine changes in live weight, digestibility and intake of herbage by early- weaned lambs on four perennial grasses. Live weight gains of lambs over the grazing season on tall fescue pasture were not different from those on perennial ryegrass, but were lower than those on smooth bromegrass and orchard-

R. L. Reid; Karen Powell; J. A. Balasko; C. C. McCormick

2010-01-01

309

PERFORMANCE OF LAMBS ON PERENNIAL RYEGRASS, SMOOTH BROMEGRASS, ORCHARDGRASS AND TALL FESCUE PASTURES II. MINERAL UTILIZATION, IN VITRO DIGESTIBILITY AND CHEMICAL COMPOSITION OF HERBAGE 1 ,2  

Microsoft Academic Search

SUMMARY Mineral balance trials with lambs fed peren- nial ryegrass, smooth bromegrass, orchardgrass and tall fescue herbage at two growth stages in 2 years showed significant effects of date of cutting and grass species on the concentration, apparent absorption (AA) and retention of major elements. Concentrations of calcium, phosphorus, potassium and sulfur declined with maturity, with little change in magnesium.

Karen Powell; R. L. Reid; J. A. Balasko

2010-01-01

310

Dynamics of the soil nematode food web and nutrient pools under tall fescue lawns established on soil matrices resulting from common urban development activities  

Microsoft Academic Search

Human activity in urbanizing areas often disturbs the soil profile, but little is known of its effects on subsequent soil food web dynamics and biogeochemical cycling. We assessed dynamics of the soil nematode food web and nutrient pools in tall fescue lawns created on either disturbed topsoil or subsoil, with or without compost amendment, and managed under three nitrogen fertilizer

Zhiqiang Cheng; Parwinder S. Grewal

2009-01-01

311

Evaluation of competitive effects of green alder, willow and other tall shrubs on white spruce and lodgepole pine in Northern Alberta  

Microsoft Academic Search

In boreal forests of western Canada, lodgepole pine (Pinus contorta Dougl. ex. Loud.) and white spruce (Picea glauca (Moench) Voss) often grow together with numerous tall shrubs such as green alder (Alnus crispa (Ait.) Pursh) and little-tree willow (Salix spp.). In an area south of Grande Prairie, Alberta, Canada, we examined the effects of shrubs, herbs and other trees on

Francesco Cortini; Philip G. Comeau

2008-01-01

312

Modeling growth of cocksfoot (Dactylis glomerata L.) and tall fescue (Festuca arundinacea schreb.) at the end of spring in relation to herbage nitrogen status  

Microsoft Academic Search

The objective was to establish a model of vegetative regrowth of plant matter in a stand of cocksfoot and tall fescue according to their nitrogen status. For three years (1989–1991), at the end of each spring, we studied regrowths in relation to differing supplies of nitrogen (120 kg\\/ha or low supply or nil). The herbage nitrogen status (IN) was estimated

M. Duru; H. Ducrocq; V. Tirilly

1995-01-01

313

Looking back in time: conducting a cohort study of the long-term effects of treatment of adolescent tall girls with synthetic hormones  

PubMed Central

Objective Public health research is an endeavour that often involves multiple relationships, far-reaching collaborations, divergent expectations and various outcomes. Using the Tall Girls Study as a case study, this paper will present and discuss a number of methodological, ethical and legal challenges that have implications for other public health research. Approach The Tall Girls Study was the first study to examine the long-term health and psychosocial effects of oestrogen treatment for tall stature. Results In undertaking this study the research team overcame many hurdles: in maintaining collaboration with treating clinicians and with the women they had treated as girls - groups with opposing points of view and different expectations; using private practice medical records to trace women who had been patients up to forty years earlier; and exploring potential legal issues arising from the collection of data related to treatment. Conclusion While faced with complex challenges, the Tall Girls Study demonstrated that forward planning, ongoing dialogue between all stakeholders, transparency of processes, and the strict adherence to group-developed protocols were keys to maintaining rigour while undertaking pragmatic research. Implications Public health research often occurs within political and social contexts that need to be considered in the planning and conduct of studies. The quality and acceptability of research findings is enhanced when stakeholders are engaged in all aspects of the research process. PMID:22168546

2011-01-01

314

The Future Can Differ From The Past This is a book of tall claims about evolution: That it can become uncontroversial;  

E-print Network

the origin of other species, the fossil record as evidence for evolution, and the constant refrainChapter 1 The Future Can Differ From The Past This is a book of tall claims about evolution to learn them, once their implications are understood; that evolution and religion, those old enemies who

Wilson, David. S.

315

Decrements in Children's Reponses to "Big" and "Tall": A Reconsideration of the Potential Cognitive and Semantic Causes. Kansas Working Papers in Linguistics, Vol. 5, No. 2.  

ERIC Educational Resources Information Center

A decline exists in children's ability at ages 4 and 5 to accurately respond to the difference between polar adjectives such as "big" and "tall.""Taller" and "bigger" are both taken to mean "having a higher top point," rather than "bigger" meaning "greater overall mass." Two hypotheses are put forth to explain this. The "strong cognitive…

Gathercole, Virginia C. Mueller

316

Fabrication of silica nano/micro-fibers doped with one-dimensional assembly of silver nanoparticles.  

PubMed

Nano/micro fibers doped with metal nanocrystals are of great interest both theorectically and practically. Nevertheless, the ordered assembly of metal nanocrystals with desired patterns in nano/micro fibers still remains a big challenge, which constrains the further development of the performance of the material. In this investigation, we propose a facile strategy based on the sol-gel and coaxial electrospinning technique to fabricate silica submicron fibers incorporating ordered 1D array of silver nanoparticles. The silver nanoparticles align strictly in a head-to-tail manner in silica fibers, and their size, shape and population are conveniently controlled through tailoring the properties of the precursor solutions and the electrospinning parameters. Therefore, the plasmon property of the obtained fibers is tuned with great freedom. The fabrication method applied here holds great potential for low-cost preparation of metal/glass composite fibers for nano/micro optical applications in general. PMID:23646733

Ma, Zhijun; Dong, Guoping; Peng, Mingying; Tan, Dezhi; Zhang, Liaolin; Qiu, Jianrong

2013-01-01

317

[Sorption of atrazine onto nano-SiO2 and nano-kaolin particles].  

PubMed

With the widespread application of nano-materials, more and more attentions are paid to the potential environmental effects of the nano-materials and their roles in the transport and transformation processes of organic pollutants. The sorption behaviors of atrazine onto nano-SiO2 and nano-kaolin were studied using a batch equilibration method, and the influences of ionic strength, sorbents concentration and pH were also investigated. The results showed that the sorption of atrazine onto nano-SiO2 and nano-kaolin decreased with the increase of ionic strength. Freundlich coefficient (Kf) of nano-SiO2 and nano-kaolin decreased from 25.55 to 18.35 and from 85.85 to 20.57 respectively when ionic strength increased from 0.001 mol x L(-1) to 0.1 mol x L(-1). The variation in concentration of nano-SiO2 had no significant influence on the sorption of atrazine. However, Kf decreased from 71.55 to 37.22 when the concentration of nano-kaolin increased from 5 g x L(-1) to 20 g x L(-1). With the increase of pH, the sorption of atrazine onto the two nano-particles decreased obviously, which indicated the speciation change of atrazine was the dominant factor controlling its sorption processes on two nanoparticles. PMID:18763524

Li, Ying; Lu, Jia-juan; Shi, Bao-you; Wu, Yu-ying

2008-06-01

318

Clinical, cytogenetic and molecular characteristics of 14 T-ALL patients carrying the TCRbeta-HOXA rearrangement: a study of the Groupe Francophone de Cytogénétique Hématologique.  

PubMed

Recently, we and others described a new chromosomal rearrangement, that is, inv(7)(p15q34) and t(7;7)(p15;q34) involving the T-cell receptor beta (TCRbeta) (7q34) and the HOXA gene locus (7p15) in 5% of T-cell acute lymphoblastic leukemia (T-ALL) patients leading to transcriptional activation of especially HOXA10. To further address the clinical, immunophenotypical and molecular genetic findings of this chromosomal aberration, we studied 330 additional T-ALLs. This revealed TCRbeta-HOXA rearrangements in five additional patients, which brings the total to 14 cases in 424 patients (3.3%). Real-time quantitative PCR analysis for HOXA10 gene expression was performed in 170 T-ALL patients and detected HOXA10 overexpression in 25.2% of cases including all the cases with a TCRbeta-HOXA rearrangement (8.2%). In contrast, expression of the short HOXA10 transcript, HOXA10b, was almost exclusively found in the TCRbeta-HOXA rearranged cases, suggesting a specific role for the HOXA10b short transcript in TCRbeta-HOXA-mediated oncogenesis. Other molecular and/or cytogenetic aberrations frequently found in subtypes of T-ALL (SIL-TAL1, CALM-AF10, HOX11, HOX11L2) were not detected in the TCRbeta-HOXA rearranged cases except for deletion 9p21 and NOTCH1 activating mutations, which were present in 64 and 67%, respectively. In conclusion, this study defines TCRbeta-HOXA rearranged T-ALLs as a distinct cytogenetic subgroup by clinical, immunophenotypical and molecular genetic characteristics. PMID:17039236

Cauwelier, B; Cavé, H; Gervais, C; Lessard, M; Barin, C; Perot, C; Van den Akker, J; Mugneret, F; Charrin, C; Pagès, M P; Grégoire, M-J; Jonveaux, P; Lafage-Pochitaloff, M; Mozzicconacci, M J; Terré, C; Luquet, I; Cornillet-Lefebvre, P; Laurence, B; Plessis, G; Lefebvre, C; Leroux, D; Antoine-Poirel, H; Graux, C; Mauvieux, L; Heimann, P; Chalas, C; Clappier, E; Verhasselt, B; Benoit, Y; Moerloose, B D; Poppe, B; Van Roy, N; Keersmaecker, K D; Cools, J; Sigaux, F; Soulier, J; Hagemeijer, A; Paepe, A D; Dastugue, N; Berger, R; Speleman, F

2007-01-01

319

Low PKCa expression within the MRD-HR stratum defines a new subgroup of childhood T-ALL with very poor outcome  

PubMed Central

Pediatric T-cell Acute Lymphoblastic Leukemia (T-ALL) outcome has improved in the last decades, yet one patient in every four still relapses. Except treatment response and immunophenotype, few markers are reliably prognostic in pediatric T-ALL patients. Aiming to improve T-ALL risk stratification, we investigated a new candidate biomarker with potential prognostic relevance. A phosphoproteomic screening of 98 pediatric T-ALL samples at diagnosis had been performed using the high-throughput Reverse Phase Protein Arrays technique, which led to the identification of PKC?S657 as an activated protein with a broad variation among T-ALL samples. To evaluate PKC? potential as a prognostic biomarker, PKC? expression was analyzed using RQ-PCR in a cohort of 173 patients, representative of ALL2000-ALLR2006 AIEOP study. A threshold of PKC? expression with the highest discrimination for incidence of relapse was identified. Patients with PKC? down-regulation, compared to patients with PKC? levels above the threshold, presented a markedly increased cumulative incidence of relapse (43.8% vs. 10.9%, P<0.001), as well as a worse 4-year overall survival (66% vs. 87.9%, P=0.002) and event-free survival (53.1% vs. 85.2%, P=0.002). In particular, low PKC? expression identified cases with extremely poor outcome within the high-risk minimal residual disease (MRD) stratum, their incidence of relapse being of 69% vs. 15% in the high PKC? levels group. In a multivariate analysis adjusting for main prognostic features, PKC? proved to be an independent prognostic factor related to incidence of relapse. Very high risk patients within the high-risk MRD stratum, identified by PKC? expression, could be proposed for experimental therapeutic protocols. PMID:25026300

Milani, Gloria; Rebora, Paola; Accordi, Benedetta; Galla, Luisa; Bresolin, Silvia; Cazzaniga, Gianni; Buldini, Barbara; Mura, Rossella; Ladogana, Saverio; Giraldi, Eugenia; Conter, Valentino; Kronnie, Geertruy Te; Valsecchi, Maria Grazia; Basso, Giuseppe

2014-01-01

320

Nano-fibrous scaffolds for tissue engineering  

Microsoft Academic Search

With the ability to form nano-fibrous structures, a drive to mimic the extracellular matrix (ECM) and form scaffolds that are an artificial extracellular matrix suitable for tissue formation has begun. These nano-fibrous scaffolds attempt to mimic collagen, a natural extracellular matrix component, and could potentially provide a better environment for tissue formation in tissue engineering systems. Three different approaches toward

L. A. Smith; P. X. Ma

2004-01-01

321

Nano-Curcumin Inhibits Proliferation of Esophageal Adenocarcinoma Cells and Enhances the T Cell Mediated Immune Response  

PubMed Central

In Western countries the incidence of the esophageal adenocarcinoma (EAC) has risen at a more rapid rate than that of any other malignancy. Despite intensive therapies this cancer is associated with extreme high morbidity and mortality. For this reason, novel effective therapeutic strategies are urgently required. Dendritic Cell (DC)-based immunotherapy is a promising novel treatment strategy, which combined with other anti-cancer strategies has been proven to be beneficial for cancer patients. Curcumin (diferuloylmethane), is a natural polyphenol that is known for its anti-cancer effects however, in it’s free form, curcumin has poor bioavailability. The aim of this study was to investigate whether using a highly absorptive form of curcumin, dispersed with colloidal nano-particles, named Theracurmin would be more effective against EAC cells and to analyze if this new compound affects DC-induced T cell response. As a result, we show efficient uptake of nano-curcumin by the EAC cell lines, OE33, and OE19. Moreover, nano-curcumin significantly decreased the proliferation of the EAC cells, while did not affect the normal esophageal cell line HET-1A. We also found that nano-curcumin significantly up-regulated the expression of the co-stimulatory molecule CD86 in DCs and significantly decreased the secretion of pro-inflammatory cytokines from in vitro activated T cells. When we combined T cells with nano-curcumin treatment in OE19 and OE33, we found that the basic levels of T cell induced cytotoxicity of 6.4 and 4.1%, increased to 15 and 13%, respectively. In conclusion, we found that nano-curcumin is effective against EAC, sensitizes EAC cells to T cell induced cytotoxicity and decreases the pro-inflammatory signals from T cells. Combining DC immunotherapy with nano-curcumin is potentially a promising approach for future treatment of EAC. PMID:23755374

Milano, Francesca; Mari, Luigi; van de Luijtgaarden, Wendy; Parikh, Kaushal; Calpe, Silvia; Krishnadath, Kausilia K.

2013-01-01

322

TryEngineering: Nano Waterproofing  

NSDL National Science Digital Library

This is a lesson plan that explores how nanotechnology has impacted the design and engineering of many everyday items, from paint to fabrics. Students learn about the hydrophobic effect (the tendency of a substance to repel water). In this lesson for Grades 6-10, students learn about nanotechnology and its application in creating waterproof surfaces. They will then work in teams to develop a waterproof material and compare their results with nano waterproof materials developed recently by engineers and scientists. The driving question of the lesson: How are products re-engineered at the nano level to develop desired properties? The lesson includes objectives and learner outcomes, problem sets, student guides, recommended reading, illustrated procedures, worksheets, and background information. Editor's Note: The humble lotus leaf is one of nature's most water-repellant surfaces. That's because its surface sculpture has a very high static contact angle with water droplets. It features randomly oriented tiny wax tubules on top of convex-shaped cells. See Related Materials for links to an article from Scientific American describing how the lotus leaf has inspired the production of waterproofing materials, and for a link to a helpful scholarly article on Sculptured Biological Surfaces with Anti-Adhesive Properties. This collection is part of TryEngineering.org, a website maintained by the Institute of Electrical and Electronics Engineers (IEEE).

323

Validation of routine continuous airborne CO2 observations near the Bialystok Tall Tower  

NASA Astrophysics Data System (ADS)

Since 2002 in situ airborne measurements of atmospheric CO2 mixing ratios have been performed regularly aboard a rental aircraft near Bialystok (53°08´ N, 23°09´ E), a city in northeastern Poland. Since August 2008, the in situ CO2 measurements have been made by a modified commercially available and fully automated non-dispersive infrared (NDIR) analyzer system. The response of the analyzer has been characterized and the CO2 mixing ratio stability of the associated calibration system has been fully tested, which results in an optimal calibration strategy and allows for an accuracy of the CO2 measurements within 0.2 ppm. Besides the in situ measurements, air samples have been collected in glass flasks and analyzed in the laboratory for CO2 and other trace gases. To validate the in situ CO2 measurements against reliable discrete flask measurements, we developed weighting functions that mimic the temporal averaging of the flask sampling process. Comparisons between in situ and flask CO2 measurements demonstrate that these weighting functions can compensate for atmospheric variability, and provide an effective method for validating airborne in situ CO2 measurements. In addition, we show the nine-year records of flask CO2 measurements. The new system, automated since August 2008, has eliminated the need for manual in-flight calibrations, and thus enables an additional vertical profile, 20 km away, to be sampled at no additional cost in terms of flight hours. This sampling strategy provides an opportunity to investigate both temporal and spatial variability on a regular basis.

Chen, H.; Winderlich, J.; Gerbig, C.; Katrynski, K.; Jordan, A.; Heimann, M.

2012-04-01

324

Validation of routine continuous airborne CO2 observations near the Bialystok Tall Tower  

NASA Astrophysics Data System (ADS)

Since 2002 in situ airborne measurements of atmospheric CO2 mixing ratios have been performed regularly aboard a rental aircraft near Bialystok (53°08' N, 23°09' E), a city in northeastern Poland. Since August 2008, the in situ CO2 measurements have been made by a modified commercially available and fully automated non-dispersive infrared (NDIR) analyzer system. The response of the analyzer has been characterized and the CO2 mixing ratio stability of the associated calibration system has been fully tested, which results in an optimal calibration strategy and allows for an accuracy of the CO2 measurements within 0.2 ppm. Besides the in situ measurements, air samples have been collected in glass flasks and analyzed in the laboratory for mixing ratios of CO2, CO, CH4, N2O, H2, SF6 and for isotopic ratios of ?13C and ?18O in CO2. To validate the in situ CO2 measurements against reliable discrete flask measurements, we developed weighting functions that mimic the temporal averaging of the flask sampling process. Comparisons between in situ and flask CO2 measurements demonstrate that these weighting functions can compensate for atmospheric variability, and provide an effective method for validating airborne in situ CO2 measurements. In addition, we show the nine-year records of flask CO2 measurements, from which the CO2 increase rates are computed for the 300 m level (1.59 ± 0.21 ppm yr-1) and for the 2500 m level (1.77 ± 0.08 ppm yr-1). The new system, automated since August 2008, has eliminated the need for manual in-flight calibrations, and thus enables an additional vertical profile, 20 km away, to be sampled at no additional cost in terms of flight hours. This sampling strategy provides an opportunity to investigate both temporal and spatial variability on a regular basis.

Chen, H.; Winderlich, J.; Gerbig, C.; Katrynski, K.; Jordan, A.; Heimann, M.

2011-11-01

325

Vacuum nano-hole array embedded organic light emitting diodes  

NASA Astrophysics Data System (ADS)

We demonstrated a nano-hole array (NHA) embedded structure that was fabricated for organic light emitting diodes (OLEDs) using a robust reverse transfer process. The NHA structure is proposed in this study as a strategy for maximizing the diffraction strength of two dimensional photonic crystals (PCs) by engineering vacuum nano-holes inside a dielectric slab. The electroluminescence (EL) intensity of the OLED was improved by more than twice. Such an optical enhancement was evaluated by using the angular dependence of photoluminescence (PL). The FDTD simulation was carried out to optimize the NHA structure for extraction of the emission induced from both vertical and horizontal dipoles. We explored the effect of the NHA structure on the extraction improvement converted from waveguide mode by measuring EL intensities of the devices with a hemisphere lens. In addition, the transfer process employed in this study yielded extremely low surface roughness, and thus outstanding electrical characteristics.We demonstrated a nano-hole array (NHA) embedded structure that was fabricated for organic light emitting diodes (OLEDs) using a robust reverse transfer process. The NHA structure is proposed in this study as a strategy for maximizing the diffraction strength of two dimensional photonic crystals (PCs) by engineering vacuum nano-holes inside a dielectric slab. The electroluminescence (EL) intensity of the OLED was improved by more than twice. Such an optical enhancement was evaluated by using the angular dependence of photoluminescence (PL). The FDTD simulation was carried out to optimize the NHA structure for extraction of the emission induced from both vertical and horizontal dipoles. We explored the effect of the NHA structure on the extraction improvement converted from waveguide mode by measuring EL intensities of the devices with a hemisphere lens. In addition, the transfer process employed in this study yielded extremely low surface roughness, and thus outstanding electrical characteristics. Electronic supplementary information (ESI) available: The contents include details about the FDTD modeling, PL specimen fabrication, OLED device fabrication, and PL/EL measurement set-up. Further information is provided relating to the NHA substrate as well. See DOI: 10.1039/c3nr05331h

Jeon, Sohee; Jeong, Jun-Ho; Song, Young Seok; Jeong, Won-Ik; Kim, Jang-Joo; Youn, Jae Ryoun

2014-02-01

326

Murine Pten(-/-) T-ALL requires non-redundant PI3K/mTOR and DLL4/Notch1 signals for maintenance and ?c/TCR signals for thymic exit.  

PubMed

T cell acute lymphoblastic leukemias (T-ALLs) commonly display constitutively active PI3K/mTOR and Notch signaling. However, controversy surrounds whether these pathways have independent functions and whether Pten loss is sufficient to generate resistance to Notch inhibition. Here we report that Pten(-/-) T-ALL is sensitive to either PI3K/mTOR or Notch inhibition alone, each pathway controlling distinct downstream signaling events that cannot be rescued by activation of the other pathway, consistent with independent, non-redundant functions. Although many human T-ALLs display constitutively activating Notch1 mutations, primary Pten(-/-) T-ALLs expressed wild-type Notch1 and depended on the Notch ligand DLL4 in vivo. Pten(-/-) T-ALLs with or without ?c/TCR signaling responded similarly to PI3K/mTOR and Notch inhibition, although extended culture in vitro occasionally induced Notch-independent growth. However, unlike the T-ALLs lacking only Pten, eight of 23 Pten(-/-) T-ALLs that also lacked ?c/TCR signaling accumulated Notch1 mutations, suggesting crosstalk between ?c/TCR and Notch signaling. Importantly, we concluded that loss of ?c/TCR signaling also inhibited thymic exit of Pten(-/-) T-ALLs. Our results may be clinically relevant in revealing that Pten loss is not sufficient to engender resistance to Notch inhibition, uncovering a role in T-ALL for ligand-dependent induction of wild-type Notch1, and suggesting that ?c/TCR signaling could be targeted for preventing metastasis. PMID:24384093

Hagenbeek, Thijs J; Wu, Xiumin; Choy, Lisa; Sanchez-Irizarry, Cheryll; Seshagiri, Somasekar; Stinson, Jeremy; Siebel, Christian W; Spits, Hergen

2014-05-01

327

Scale effects in gas nano flows  

NASA Astrophysics Data System (ADS)

Most previous studies on gas transport in nano-scale confinements assume dynamic similarity with rarefied gas flows, and employ kinetic theory based models. This approach is incomplete, since it neglects the van der Waals forces imposed on gas molecules by the surfaces. Using three-dimensional molecular dynamics (MD) simulations of force driven gas flows, we show the significance of wall force field in nano-scale confinements by defining a new dimensionless parameter (B) as the ratio of the wall force-penetration length to the channel height. Investigation of gas transport in different nano-channels at various Knudsen numbers show the importance of wall force field for finite B values, where the dynamic similarity between the rarefied and nano-scale gas flows break down. Comparison of MD results employing molecularly structured three-dimensional walls versus reflection of gas molecules from a two-dimensional planar surface with Maxwell distribution show that the nano-confinement effects cannot be resolved by the latter approach, frequently used in kinetic theory calculations. Molecularly structured walls determine the bulk flow physics by setting a proper tangential momentum accommodation coefficient, and they also determine the transport in the near wall region. Gas nano-flows with finite B exhibit significant differences in the local density and velocity profiles, affecting the mass flow rate and the formation of Knudsen's minimum in nano-channels.

Barisik, Murat; Beskok, Ali

2014-05-01

328

Phosphorylated nano-diamond/ Polyimide Nanocomposites  

NASA Astrophysics Data System (ADS)

In this study, a novel route to synthesize polyimide (PI)/phosphorylated nanodiamond films with improved thermal and mechanical properties was developed. Surface phosphorylation of nano-diamond was performed in dichloromethane. Phosphorylation dramatically enhanced the thermal stability of nano-diamond. Poly(amic acid) (PAA), which is the precursor of PI, was successfully synthesized with 3,3',4,4'-Benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-oxydianiline (4,4'-ODA) in the solution of N,N- dimethylformamide (DMF). Pure BTDA-ODA polyimide films and phosphorylated nanodiamond containing BTDA-ODA PI films were prepared. The PAA displayed good compatibility with phosphorylated nano-diamond. The morphology of the polyimide (PI)/phosphorylated nano-diamond was characterized by scanning electron microscopy (SEM). Chemical structure of polyimide and polyimide (PI)/phosphorylated nano-diamond was characterized by FTIR. SEM and FTIR results showed that the phosphorylated nano-diamond was successfully prepared. Thermal properties of the polyimide (PI)/phosphorylated nanodiamond was characterized by thermogravimetric analysis (TGA). TGA results showed that the thermal stability of (PI)/phosphorylated nano-diamond film was increased.

Beyler-Çi?il, Asli; Çakmakçi, Emrah; Vezir Kahraman, Memet

2014-08-01

329

Nano-Scale Effects in Cylindrical Contacts Sari et al. NANO-SCALE EFFECTS IN THE ADHERENCE, SLIDING  

E-print Network

@coe.neu.edu Abstract The behavior of a nano-scale cylindrical body (e.g. a fiber), lying on a substrate and acted uponNano-Scale Effects in Cylindrical Contacts Sari et al. 1 NANO-SCALE EFFECTS IN THE ADHERENCE to the nano level, adhesion becomes an important issue in this contact problem. Thus this investigation treats

Müftü, Sinan

330

Optimum testing intervals of building emergency power supply systems in tall buildings in the Hong Kong Special Administrative Region  

NASA Astrophysics Data System (ADS)

The main objective of this study is to develop a model for the determination of optimum testing interval (OTI) of non-redundant standby plants. This study focuses on the emergency power generators in tall buildings in Hong Kong. The model for the reliability, which is developed, is applicable to any non-duplicated standby plant. In a tall building, the mobilisation of occupants is constrained by its height and the building internal layout. Occupant's safety, amongst other safety considerations, highly depends on the reliability of the fire detection and protection system, which in turn is dependent on the reliability of the emergency power generation plants. A thorough literature survey shows that the practice used in determining OTI in nuclear plants is generally applicable. Historically, the OTI in these plants is determined by balancing the testing downtime and reliability gained from frequent testing. However, testing downtime does not exist in plants like emergency power generator. Subsequently, sophisticated models have taken repairing downtime into consideration. In this study, the algorithms for the determination of OTI, and hence reliability of standby plants, are reconsidered. A new concept is introduced into the subject. A new model is developed for such purposes which embraces more realistic factors found in practice. System aging and the finite life cycle of the standby plant are considered. Somewhat more pragmatic is that the Optimum Overhauling Interval can also be determined from this new model. System unavailability grow with time, but can be reset by test or overhaul. Contrary to fixed testing intervals, OTI is determined whenever system point unavailability exceeds certain level, which depends on the reliability requirement of the standby system. An optimum testing plan for lowering this level to the 'minimum useful unavailability' level (see section 9.1 for more elaboration) can be determined by the new model presented. Cost effectiveness is accounted for by a new parameter 'tau min', the minimum testing interval (MTI). The MTI optimises the total number of tests and the total number of overhauls, when the costs for each are available. The model sets up criteria for test and overhaul and to 'announce' end of system life. The usefulness of the model is validated by a detailed analysis of the operating parameters from 8,500 maintenance records collected for emergency power generation plants in high rise buildings in Hong Kong. (Abstract shortened by UMI.)

Kwok, Yu Fat

331

A case study of elementary teachers' conceptions of environmental literacy in relationship to a tall grass prairie restoration project  

NASA Astrophysics Data System (ADS)

The purpose of this qualitative case study was to describe seven elementary teachers' conceptions of environmental literacy in relationship to a tall grass prairie restoration project and to explore ways in which the tall grass prairie restoration project for third grade contributed to enhancing educational learning experiences. The research questions were: 1. What are teachers' conceptions of environmental literacy for third grade students? 2. How does the prairie restoration trip contribute to teachers' capacity to teach for environmental literacy of third grade students? 3. What is the pedagogical value of the prairie restoration project? The theoretical frameworks underpinning this study were David Sobel's (1996) model for developmental progression in children's relationships with nature, and the North American Environmental Education Association's (2011) framework for environmental literacy. The first assertion derived from thematic data analysis of interviews, field trip observations, classroom observations, and artifacts was, The participating teachers' visions of environmental literacy for third grade students included components that spanned across a developmentally appropriate progression from cultivating empathy for living things, to fueling discovery of nature, to fostering a sense of responsibility toward the natural world . Components of environmental literacy described by teachers included being at ease in the natural environment, appreciation and respect, wonder and curiosity, awareness and interdependence, sense of agency, responsibility and service, and environmental knowledge. The second assertion stemming from thematic data analysis was, The prairie restoration project and related curriculum have pedagogical value that included and exceeded addressing state science standards. In addition to addressing state science standards identified by teachers, the curriculum related to the prairie restoration project served as an agent of curricular cohesion to integrate a variety of subject areas, developed scientific ways of thinking, provided life experience for children, and fostered authentic learning experiences through concrete connections. It also provided a means to enhance the presence of science and social studies in elementary curriculum. Themes emerging from qualitative data analysis resonated with Sobel's model of progressive stages in children's relationships with nature, and resulted in a tool potentially useful for design of elementary curriculum aimed at developing environmental literacy.

Shume, Teresa Jayne

332

Web-FACE: a new canopy free-air CO2 enrichment system for tall trees in mature forests.  

PubMed

The long-term responses of forests to atmospheric CO2 enrichment have been difficult to determine experimentally given the large scale and complex structure of their canopy. We have developed a CO2 exposure system that uses the free-air CO2 enrichment (FACE) approach but was designed for tall canopy trees. The system consists of a CO2-release system installed within the crown of adult trees using a 45-m tower crane, a CO2 monitoring system and an automated regulation system. Pure CO2 gas is released from a network of small tubes woven into the forest canopy (web-FACE), and CO2 is emitted from small laser-punched holes. The set point CO2 concentration ([CO2]) of 500 µmol mol(-1) is controlled by a pulse-width modulation routine that adjusts the rate of CO2 injection as a function of measured [CO2] in the canopy. CO2 consumption for the enrichment of 14 tall canopy trees was about 2 tons per day over the whole growing season. The seasonal daytime mean CO2 concentration was 520 µmol mol(-1). One-minute averages of CO2 measurements conducted at canopy height in the center of the CO2-enriched zone were within ±20% and ±10% of the target concentration for 76% and 47% of the exposure time, respectively. Despite the size of the canopy and the windy site conditions, performance values correspond to about 75% of that reported for conventional forest FACE with the added advantage of a much simpler and less intrusive infrastructure. Stable carbon isotope signals captured by 80 Bermuda grass (Cynodon dactylon) seedlings distributed within the canopy of treated and control tree districts showed a clearly delineated area, with some nearby individuals having been exposed to a gradient of [CO2], which is seen as added value. Time-integrated values of [CO2] derived from the C isotope composition of C. dactylon leaves indicated a mean (±SD) concentration of 513±63 µmol mol(-1) in the web-FACE canopy area. In view of the size of the forest and the rough natural canopy, web-FACE is a most promising avenue towards natural forest experiments, which are greatly needed. PMID:24599362

Pepin, Steeve; Körner, Christian

2002-09-01

333

Nano-Ceramic Coated Plastics  

NASA Technical Reports Server (NTRS)

Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (<100 C) is also a key to generating these ceramic coatings on the plastics. One possible way of processing nanoceramic coatings at low temperatures (< 90 C) is to take advantage of in-situ precipitated nanoparticles and nanostructures grown from aqueous solution. These nanostructures can be tailored to ceramic film formation and the subsequent microstructure development. In addition, the process provides environment- friendly processing because of the aqueous solution. Low-temperature processing has also shown versatility to generate various nanostructures. The growth of low-dimensional nanostructures (0-D, 1-D) provides a means of enhancing the crystallinity of the solution-prepared films that is of importance for photocatalytic performance. This technology can generate durable, fully functional nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

Cho, Junghyun

2013-01-01

334

Ducking as a means of resistance to herbivory in tall goldenrod, Solidago altissima.  

PubMed

Many populations of goldenrod show a peculiar, genetically controlled stem dimorphism. In Solidago altissima, for instance, while most stems are erect, a sizable minority (the "candy-cane" stems) nod at the apex during growth. We used data from three studies to test the hypothesis that this candy-cane growth form confers resistance to herbivory. In a controlled growth trial, we showed that nodding is a temporary phenomenon that coincides with the oviposition period of at least two common apex-attacking herbivores: the tephritid galler Eurosta solidaginis and the gall midge Rhopalomyia solidaginis. In a large field survey, stems of candy-cane genets were only half as likely to be ovipunctured by E. solidaginis. In a common-garden study, candy-cane stems were less likely to be ovipunctured by E. solidaginis, and they were galled only half as often by R. solidaginis as erect stems. These results suggest that the candy-cane stems of goldenrod possess a resistance strategy that allows them to essentially duck and hide from certain herbivores. PMID:19137934

Wise, Michael J; Abrahamson, Warren G

2008-12-01

335

NanoSight LM10 HS Operating Manual  

E-print Network

1 NanoSight LM10 HS Operating Manual © 2009 NanoSight Ltd. NanoSight Ltd., Minton Park, Amesbury ........................................................... 8 #12;3 1. Important Notes The LM10HS option for NanoSight LM10 systems is designed to supply notify NanoSight if you find the contents to be incomplete or if any parts appear to be damaged in any

Fygenson, Deborah Kuchnir

336

Attostreaking with metallic nano-objects  

NASA Astrophysics Data System (ADS)

The application of atto-second streaking spectroscopy (ASS) to direct time-domain studies of the plasmonic excitations in metallic nano-objects is addressed theoretically. The streaking spectrograms for a rectangular gold nano-antenna and spherical gold clusters are obtained within strong field approximation using classical electron trajectory calculations. The results reported here for spherical clusters are also representative of spherical nano-shells. This study demonstrates that ASS allows for detailed characterization of plasmonic modes, including near-field enhancement, frequency and decay rate. The role of the inhomogeneity of the induced electric fields is also demonstrated.

Borisov, A. G.; Echenique, P. M.; Kazansky, A. K.

2012-02-01

337

NanoSpace - Virtual Amusement Park  

NSDL National Science Digital Library

NanoSpace, a free website developed by the Rensselear Polytechnic Institute, was created to increase science literacy utilizing an amusement park. NanoSpace is designed to teach science to elementary and middle school students through more than 25 games and animations that entice kids to learn more about atoms and molecules in NanoSpace. Visitors can try to beat the clock in the Periodic Memory and click-and-drag atoms to construct molecules in "Build `Em." Answer multiple-choice questions in "Who wants to be a Quidecillionaire?," and hope the answer is correct before you fall down to the bottom rung again.

Project, The M.

338

Preparation of hydrophobic nano-silver colloid and aqueous nano-silver colloid by phase transfer  

Microsoft Academic Search

A novel and facile method to prepare hydrophobic nano-silver colloid and aqueous coordinate was proposed. Chemical reduction of silver nitrate in a tributyl phosphate (TBP) solution containing polyvinylpyrrolidone (PVP) was conducted and stable hydrophobic nano-silver\\/TBP\\/PVP colloids were obtained. Adopting a phase transfer process, the as-prepared colloids can be diverted into an aqueous system to obtain hydrophilic nano-silver colloids. The resultant

Shanshan Wei; Xiangyang Xu; Yuejun Liu; Junming Yang

2011-01-01

339

Characterization of Integrated Nano Materials  

NASA Astrophysics Data System (ADS)

Depending on the level of the technological developments, the characterization techniques are mature to support them or still require protocol definition and relevance demonstration for the issues addressed. For Beyond CMOS and Extreme CMOS devices, the integration of nano-objects like nanowires and carbon nanotubes, brings about analysis requirements that are at the frontier of the state-of-the-art characterization techniques. The specific limitations of the use of the existing physical and chemical characterization techniques for integrated nanomaterials are highlighted. In the case of Scanning Probe Microscopy, in-situ localization and positioning are specifically challenging and data analysis is mainly statistical. It is also shown how specific sample preparation may serve the extraction of the required 3D information in particular for Electron Microscopy. The measurement developments related to NEMS technologies guided by the need for dynamic characterization of these components are covered too.

Chabli, Amal; Cherns, Peter; Chevalier, Nicolas; Cooper, David; Lafond, Dominique; Bertin, François; Blanc, Henri; Brenac, Ariel; Andreucci, Philippe; Gabriel, Jean-Christophe

2009-09-01

340

Structure Determination from Powder Diffraction by Direct-Space Strategy  

NASA Astrophysics Data System (ADS)

The crystal structure determination from powder diffraction (SDPD) has attracted wide interests for its huge potential to accelerate a design, synthesis, and characterization of the materials in the fields of nano- and bio- technologies. One of the most important progresses of the SDPD is the development of the direct-space strategy. In this report, SDPD by direct-space strategy has been described. Fundamental aspects of the strategy have been demonstrated with some examples. Global optimization methods within direct-space strategy such as Grid Search, Simulated Annealing, and Genetic Algorithm have been described including detailed methodologies.

Nishibori, Eiji

341

Report on workshop to incorporate basin response in the design of tall buildings in the Puget Sound region, Washington  

USGS Publications Warehouse

On March 4, 2013, the City of Seattle and the U.S. Geological Survey (USGS) convened a workshop of 25 engineers and seismologists to provide recommendations to the City for the incorporation of amplification of earthquake ground shaking by the Seattle sedimentary basin in the design of tall buildings in Seattle. The workshop was initiated and organized by Susan Chang, a geotechnical engineer with the City of Seattle Department of Planning and Development, along with Art Frankel and Craig Weaver of the USGS. C.B. Crouse of URS Corporation, Seattle made key suggestions for the agenda. The USGS provided travel support for most of the out-of-town participants. The agenda and invited attendees are given in the appendix. The attendees included geotechnical and structural engineers working in Seattle, engineers with experience utilizing basin response factors in other regions, and seismologists who have studied basin response in a variety of locations. In this report, we summarize the technical presentations and the recommendations from the workshop.

Chang, Susan; Frankel, Arthur D.; Weaver, Craig S.

2014-01-01

342

Water and phosphorus content affect PAH dissipation in spiked soil planted with mycorrhizal alfalfa and tall fescue.  

PubMed

Polycyclic aromatic hydrocarbon (PAH) dissipation efficiency can be increased in the plant rhizosphere, but may be affected by various environmental factors. We investigated the effects of the watering regime and phosphorus concentration on PAH dissipation in the rhizosphere of mycorrhizal plants in a pot experiment. Two plant species, alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea), were co-cultured and inoculated with an arbuscular mycorrhizal (AM) fungus (Glomus intraradices) in PAH (phenanthrene (PHE)=500 mg kg(-1), pyrene (PYR)=500 mg kg(-1), dibenzo(a,h)anthracene (DBA)=65 mg kg(-1)) spiked agricultural soil for 6 weeks. Treatments with different phosphorus concentrations and watering regimes were compared. The PHE dissipation reached 90% in all treatments and was not affected by the treatments. The major finding was the significant positive impact of mycorrhizal plants on the dissipation of high molecular weight PAH (DBA) in high-water low-phosphorus treatment. Such an effect was not observed in high-water high-phosphorus and low-water low-phosphorus treatments, where AM colonization was very low. A positive linear relationship was detected between PYR dissipation and the percentage of Gram-positive PAH-ring hydroxylating dioxygenase genes in high-water high-phosphorus treatments, but not in the other two treatments with lower phosphorus concentrations and water contents. Such results indicated that the phosphorus and water regime were important parameters for the dissipation of HMW-PAH. PMID:19775720

Zhou, X B; Cébron, A; Béguiristain, T; Leyval, C

2009-10-01

343

Improvement of paper mulberry tolerance to abiotic stresses by ectopic expression of tall fescue FaDREB1.  

PubMed

Dehydration-responsive element binding/C-repeat-binding factors (DREB/CBF) control the activity of multiple stress response genes and therefore represent attractive targets for genetic improvement of abiotic stress tolerance. Paper mulberry (Broussonetia papyrifera L. Vent) is well known for its bark fibers and high levels of chalcone and flavonoid derivatives. Transgenic paper mulberry plants expressing a tall fescue (Festuca arundinacea Schreb.) FaDREB1 gene under the control of CaMV 35S were produced to examine the potential utility of FaDREB1 to increase the tolerance of paper mulberry plants to abiotic stress. The overexpressing FaDREB1 plants showed higher salt and drought tolerance than the wild-type plants (WT). After 13 days of withholding water, or 15 days in the presence of 250 mM NaCl, all the WT plants died, while the over-expressing FaDREB1 plants survived. The FaDREB1 plants had higher leaf water and leaf chlorophyll contents, accumulated more proline and soluble sugars, and had less ion leakage (which reflects membrane damage) than the WT plants had under high salt- and water-deficient conditions. The 35S promoter-driven expression of FaDREB1 did not cause growth retardation under normal growth conditions. Therefore, improved tolerance to multiple environmental stresses in paper mulberry might be achieved via genetic engineering through the ectopic expression of an FaDREB1 gene. PMID:22170439

Li, Meiru; Li, Yan; Li, Hongqing; Wu, Guojiang

2012-01-01

344

Cloning and Characterization of a Phragmites australis Phytochelatin Synthase (PaPCS) and Achieving Cd Tolerance in Tall Fescue  

PubMed Central

The production of phytochelatins (PCs) provides an important means for plants to achieve tolerance to cadmium (Cd) toxicity. A reed gene encoding PC synthase (PaPCS) was isolated and its function tested through its heterologous expression in a strain of yeast sensitive to Cd. Subsequently, the Cd sensitive and high biomass accumulating species tall fescue was transformed either with PaPCS or PaGCS (a glutamyl cysteine synthetase gene of reed) on their own (single transformants), or with both genes together in the same transgene cassette (double transformant). The single and double transformants showed greater Cd tolerance and accumulated more Cd and PC than wild type plants, and their Cd leaf/root ratio content was higher. The ranking in terms of Cd and PC content for the various transgenic lines was double transformants>PaGCS single transformants>PaPCS single transformants>wild type. Thus PaGCS appears to exert a greater influence than PaPCS over PC synthesis and Cd tolerance/accumulation. The double transformant has interesting potential for phytoremediation. PMID:25133575

Zhao, Cuizhu; Xu, Jin; Li, Qiang; Li, Shuo; Wang, Peng; Xiang, Fengning

2014-01-01

345

Estimation of abundance and distribution of two moist tall grasses in the Watarase wetland, Japan, using hyperspectral imagery  

NASA Astrophysics Data System (ADS)

The dominant grasses in a wetland are of critical concern for the wetland's ecological integrity, because these species provide the habitats for many small plants and animals. In this study, we used hyperspectral imagery to map the distributions of two dominant tall grasses ( Miscanthus sacchariflorus (Maxim.) Benth and Phragmites australis (Cav.) Trin. ex Stend) in the Watarase wetland, in central Japan. Stepwise multiple linear regression analysis was applied to the hyperspectral data to predict the shoot density and biomass of the two grasses. The independent data sets included original reflectance, band ratios, significant components identified by principal components analysis (PCA), and significant components identified by decision boundary feature extraction (DBFE). The coefficient of determination ( R2) and the root-mean-square error (RMSE) of model calibration and validation were used to evaluate the models. The significant DBFE components showed better ability at predicting shoot density of the two grasses than the other variables in the validating areas. The RMSE values were 7.40/m 2 for M. sacchariflorus and 13.09/m 2 for P. australis, which amounted to errors of around 10.0% and 12.6%, respectively, of the maximum shoot density measured during our surveys. All variables showed similar performance at predicting biomass, but the results were less accurate than those for shoot density. Considering the performance of the DBFE components for both shoot density and biomass prediction, we suggest that these are the best indicators for estimating the abundance of the two grasses.

Lu, Shan; Shimizu, Yo; Ishii, Jun; Funakoshi, Syo; Washitani, Izumi; Omasa, Kenji

346

Impacts of Sustained Use of Dairy Manure Slurry and Fertilizers on Populations of Pratylenchus penetrans under Tall Fescue.  

PubMed

Various manures and composts have been reported to reduce population densities of plant-parasitic nematodes. Dairy manure slurry is often used as a primary source of nitrogen for forage crops. This study was conducted to determine the effects of dairy manure on population densities of Pratylenchus penetrans parasitizing tall fescue. Beginning in 1994, dairy manure and inorganic fertilizer were applied after each harvest (2 to 4 times/year) at rates of 50 and 100 kg NH-N/ha; control plots were not treated. Nematode populations in soil and roots were determined at 19 sample dates during the fourth (1997), fifth (1998), and sixth (1999) years of manure and fertilizer applications. The sustained use of dairy manure and fertilizer increased population densities of P. penetrans. Our results contrast with many previous studies demonstrating that application of manures decreases population densities of plant-parasitic nematodes. Frequent applications of moderate amounts of manure to a perennial grass crop may have prevented the development of nematode-toxic levels of ammonia or other toxic substances such as nitrous acid or volatile fatty acids. Two years with no additional manure applications were required for P. penetrans population densities to return to levels similar to fertilized or untreated soil. PMID:19262862

Forge, T A; Bittman, S; Kowalenko, C G

2005-06-01

347

Effect of simulated acid rain on the mutualism between tall fescue (Festuca arundinacea) and an endophytic fungus (Acremonium coenophialum)  

SciTech Connect

Biotic interactions between plants and microorganisms have the potential to be affected by acidic precipitation. I examined the effect of simulated sulfuric acid rain on the mutualism between a perennial forage grass (Festuca arundinacea) and a fungal endophyte (Acremonium coenophialum). Acid water was supplied as mists sprayed onto leaf surfaces or as water added to the soil for two groups in a greenhouse: one group had high levels of endophyte infection, while the other was predominantly noninfected. Control plants received distilled water (pH 6), while others received sulfuric acid water at pH 4.5 or pH 3. Plants were harvested after 4, 6, 8, and 23 wk. Leaf endophyte infection intensity as measured by hyphal counts was not affected by acid water treatment. Root mass and root: shoot ratios generally decreased with increasing acidity of both foliar sprays and soil water, but shoot mass was mostly not affected. There was a significant pH x infection interaction for plants exposed to acidic foliar sprays for 4 wk; root and shoot mass decreased with acidity, but only for infected plants. It was found that acid rain may be deleterious to tall fescue growth at specific stages of development, but biomass production in response to acid rain is not likely to be influenced by fungal endophytes within mature plants. 55 refs., 2 figs., 3 tabs.

Cheplick, G.P. (Univ. of Wisconsin, Whitewater (United States))

1993-03-01

348

A nano-stepping robotic instrumentation platform  

E-print Network

The development of an Autonomous Nano-stepping Tool (ANT) system is presented. Each ANT is a small, tripodal, robotic instrument capable of untethered precision motion within a quasi-three-dimensional workspace of arbitrary ...

Wahab, Adam Joseph

2013-01-01

349

[Nano-safety science for sustainable nanotechnology].  

PubMed

Recently, it is concerned that nanomaterials induce undesirable biological responses (NanoTox) which is different from conventional materials attributed to their unique physicochemical properties in the world. However, for our enjoying the benefits of nanomateirals, it is most important not to regulate nanomaterials in the blind way but to assure the security of nanomaterials and support the development of nanomaterial industries. These are duty of our country to be advanced country, technology-oriented nation and intellectual property nation. From these viewpoints, we are engaged on not NanoTox study but Nano-safety science study. In this review, we will introduce our Nano-safety science study using mainly silica nanoparticle. PMID:24882650

Yoshioka, Yasuo; Tsutsumi, Yasuo

2014-01-01

350

A Nano-Introduction to Nanotechnology  

NSDL National Science Digital Library

A very small and generic introduction to the subject of nanotechnology. What makes nanoscience special? What is the history of nano? What can nanotechnology be used for by scientist and industry? What are the ethical and enviromental challenges?

Liang, Barbara

2010-10-29

351

Opportunities and Challenges of Nano Satellites  

E-print Network

-satellite is a low cost and short development-time satellite with mass of less than 50kg. Image courtesy of NASA "Normal" satellite (LANDSAT 7/NASA) "Normal" satellite (LANDSAT 7/NASA) Nano-satellite (Cute1.7+APD

352

DNA Assembly Line for Nano-Construction  

ScienceCinema

Building on the idea of using DNA to link up nanoparticles scientists at Brookhaven National Lab have designed a molecular assembly line for high-precision nano-construction. Nanofabrication is essential for exploiting the unique properties of nanoparticl

Oleg Gang

2010-01-08

353

DNA Assembly Line for Nano-Construction  

SciTech Connect

Building on the idea of using DNA to link up nanoparticles scientists at Brookhaven National Lab have designed a molecular assembly line for high-precision nano-construction. Nanofabrication is essential for exploiting the unique properties of nanoparticl

Oleg Gang

2009-03-25

354

Supramolecular nano-stamping : analyzing market potential  

E-print Network

An analysis was carried out on the process of Supramolecular Nano-Stamping (SuNS) in order to determine whether or not the science involved has market potential in the DNA microarray industry. This industry is rapidly ...

DePalma, Christina Maria

2005-01-01

355

The influence of a mulching rotary mower on nutrient cycling, turfgrass quality, thatch, and temperature of a tall fescue (Festuca arundinacea Schreb.) turf  

E-print Network

THE INFLUENCE OF A MULCHING ROTARY MOWER ON NUTRIENT CYCLING' TURFGRASS QUALITY' THATCH& AND TEMPERATURE OF A TALL FESCUE (FESTUCA ARUNDINACEA SCHREB ~ ) TURF A Thesis BY STEVEN DAVID GRIGGS Submitted to the Graduate College of Texas A... (FESTUCA ARUNDINACEA SCHREB. ) TURF A Thesis BY STEVEN DAVID GRIGGS Approved as to style and content by: James B. Beard C -Chairman of Committee) Garald L. Horst (Co-chairman of Committee) Ronald . ewton (M er) E. C. A. R ead of Department) May...

Griggs, Steven David

2012-06-07

356

Estimates of net CO 2 flux by application of equilibrium boundary layer concepts to CO 2 and water vapor measurements from a tall tower  

Microsoft Academic Search

fluxes that affects the CO2 and water vapor mixing ratios. We apply quasi-equilibrium concepts for the terrestrial ABL to measurements of CO2 and water vapor made within the ABL from a tall tower (396 m) in Wisconsin. We suppose that CO2 and water vapor mixing ratios in the ABL approach an equilibrium on timescales longer than a day: a balance

Brent R. Helliker; Joseph A. Berry; Alan K. Betts; Peter S. Bakwin; Kenneth J. Davis; A. Scott Denning; James R. Ehleringer; John B. Miller; Martha P. Butler; Daniel M. Ricciuto

2004-01-01

357

Estimates of net CO2 flux by application of equilibrium boundary layer concepts to CO2 and water vapor measurements from a tall tower  

Microsoft Academic Search

Convective turbulence within the atmospheric boundary layer (ABL) and movement of the ABL over the surface results in a large spatial (104–105 km2) integration of surface fluxes that affects the CO2 and water vapor mixing ratios. We apply quasi-equilibrium concepts for the terrestrial ABL to measurements of CO2 and water vapor made within the ABL from a tall tower (396

Brent R. Helliker; Joseph A. Berry; Alan K. Betts; Peter S. Bakwin; Kenneth J. Davis; A. Scott Denning; James R. Ehleringer; John B. Miller; Martha P. Butler; Daniel M. Ricciuto

2004-01-01

358

Nano-Sized Carriers for Drug Delivery  

Microsoft Academic Search

Drug delivery is an important issue, especially with a new generation of therapeutics, which are either unstable in the biological\\u000a environment, have poor transport properties across biological membranes, are insoluble in water, or have very low bioavailability.\\u000a Nano-sized drug carriers can address some of the above issues and enhance their therapeutic efficacy. Different types of nano-sized\\u000a carriers, such as nanoparticles,

Sanjeeb K. Sahoo; Tapan K. Jain; Maram K. Reddy; Vinod Labhasetwar

359

Catalytic wateroxidation on derivatized nanoITO  

SciTech Connect

Electrocatalytic water oxidation occurs on high surface area, nanocrystalline ITO (nanoITO) surface-derivatized by phosphonate-binding of the catalyst [Ru(Mebimpy)(4,4?-((HO){sub 2}OPCH{sub 2}){sub 2}bpy)(OH{sub 2})]{sup 2+} (Mebimpy is 2,6-bis(1-methylbenzimidazol-2-yl)pyridine; bpy is 2,2?-bipyridine). With nanoITO, spectral data can be acquired on electrochemically generated intermediates and voltammograms monitored spectrophotometrically.

Chen, Zuofeng; Concepcion, Javier J; Hull, Jonathan F; Hoertz, Paul G.; Meyer, Thomas J.

2010-01-01

360

Research advances in nano-composite solders  

Microsoft Academic Search

Recently, nano-composite solders have been developed in the electronic packaging materials industry to improve the creep and thermo-mechanical fatigue resistance of solder joints to be used in service at high temperatures and under thermo-mechanical fatigue conditions. This paper reviews the driving force for the development of nano-composite solders in the electronic packaging industry and the research advances of the composite

J. Shen; Y. C. Chan

2009-01-01

361

'Chrysanthemum petal' arrangements of silver nano wires.  

PubMed

Highly ordered 'Chrysanthemum petal' arrangements of silver nano wires were fabricated in a biodegradable polymer of polyvinyl alcohol using a simple one-step blending method without any template. The degree of the arrangement increased with the decreasing content of polyvinyl alcohol. The mechanism for the formation of these 'Chrysanthemum petal' arrangements was discussed specifically. These 'Chrysanthemum petal' arrangements will be helpful to increase the electrical conductivity of silver nano wires films. PMID:25397618

Cui, Hui-Wang; Jiu, Jin-Ting; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki; Uchida, Hiroshi

2014-12-01

362

Nano-segregated polymeric film exhibiting high ionic conductivities.  

PubMed

Nanostructures can be used for the fabrication of highly functional materials transporting ions and charges. We demonstrate a new design strategy for polymeric higher ion-conductors. Phase-segregated layers of alternating mobile tetra(ethylene oxide)s (TEOs) and rigid aromatic cores where the TEO moieties are grafted from aromatic layers have been shown to be efficient to transport lithium triflate. Such segregated structures at the nanometer scale (nano-segregated structures) were prepared by in-situ photopolymerization of an aligned methacrylate liquid crystalline monomer comprising a terphenyl rigid rod mesogen having a TEO terminal chain. The ion-conductive TEO moiety remains in the highly mobile state even after polymerization, which is indicated by its low glass transition temperature (-45 degrees C). This nanostructured film exhibits an ionic conductivity parallel to the layer of 10(-3) S cm(-1) at room temperature. The highest ionic conductivity is in the level of 10(-2) S cm(-1) observed at 150 degrees C. The anisotropic ionic conductivities have been observed for the nano-segregated film. PMID:16262428

Kishimoto, Kenji; Suzawa, Tomoyuki; Yokota, Tomoki; Mukai, Tomohiro; Ohno, Hiroyuki; Kato, Takashi

2005-11-01

363

Injectable Nano-Network for Glucose-Mediated Insulin Delivery  

PubMed Central

Diabetes mellitus, a disorder of glucose regulation, is a global burden affecting 366 million people across the world. An artificial “closed-loop” system able to mimic pancreas activity and release insulin in response to glucose level changes has the potential to improve patient compliance and health. Herein we develop a glucose-mediated release strategy for the self-regulated delivery of insulin using an injectable and acid-degradable polymeric network. Formed by electrostatic interaction between oppositely charged dextran nanoparticles loaded with insulin and glucose-specific enzymes, the nanocomposite-based porous architecture can be dissociated and subsequently release insulin in a hyperglycemic state through the catalytic conversion of glucose into gluconic acid. In vitro insulin release can be modulated in a pulsatile profile in response to glucose concentrations. In vivo studies validated that these formulations provided improved glucose control in type 1 diabetic mice subcutaneously administered with a degradable nano-network. A single injection of the developed nano-network facilitated stabilization of the blood glucose levels in the normoglycemic state (<200 mg/dL) for up to 10 days. PMID:23638642

Gu, Zhen; Aimetti, Alex A.; Wang, Qun; Dang, Tram T.; Zhang, Yunlong; Veiseh, Omid; Cheng, Hao; Langer, Robert S.; Anderson, Daniel G.

2014-01-01

364

Injectable nano-network for glucose-mediated insulin delivery.  

PubMed

Diabetes mellitus, a disorder of glucose regulation, is a global burden affecting 366 million people across the world. An artificial "closed-loop" system able to mimic pancreas activity and release insulin in response to glucose level changes has the potential to improve patient compliance and health. Herein we develop a glucose-mediated release strategy for the self-regulated delivery of insulin using an injectable and acid-degradable polymeric network. Formed by electrostatic interaction between oppositely charged dextran nanoparticles loaded with insulin and glucose-specific enzymes, the nanocomposite-based porous architecture can be dissociated and subsequently release insulin in a hyperglycemic state through the catalytic conversion of glucose into gluconic acid. In vitro insulin release can be modulated in a pulsatile profile in response to glucose concentrations. In vivo studies validated that these formulations provided improved glucose control in type 1 diabetic mice subcutaneously administered with a degradable nano-network. A single injection of the developed nano-network facilitated stabilization of the blood glucose levels in the normoglycemic state (<200 mg/dL) for up to 10 days. PMID:23638642

Gu, Zhen; Aimetti, Alex A; Wang, Qun; Dang, Tram T; Zhang, Yunlong; Veiseh, Omid; Cheng, Hao; Langer, Robert S; Anderson, Daniel G

2013-05-28

365

SET-NUP214 is a recurrent ?? lineage-specific fusion transcript associated with corticosteroid/chemotherapy resistance in adult T-ALL.  

PubMed

The SET-NUP214 (TAF1/CAN) fusion gene is a rare genetic event in T-cell acute lymphoblastic leukemia (T-ALL). Eleven (6%) of 196 T-ALL patients enrolled in the French Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL) 2003 and 2005 trials harbored a SET-NUP214 transcript. SET-NUP214-positive patients were predominantly (10 [91%] of 11) T-cell receptor (TCR)-negative and strikingly associated with TCR?? lineage T-ALLs, as defined by expression of TCR??, TCR? and/or TCR? rearrangements but no complete TCR? variable diversity joining rearrangement in surface CD3/TCR-negative cases. When compared with SET-NUP214-negative patients, SET-NUP214-positive patients showed a significantly higher rate of corticosteroid resistance (91% vs 44%; P = .003) and chemotherapy resistance (100% vs 44%; P = .0001). All SET-NUP214-positive patients but one achieved complete remission, and 9 were allografted. Despite the poor early-treatment sensitivity, the outcome of SET-NUP214-positive patients was similar to that of SET-NUP214-negative patients. PMID:24449214

Ben Abdelali, Raouf; Roggy, Anne; Leguay, Thibaut; Cieslak, Agata; Renneville, Aline; Touzart, Aurore; Banos, Anne; Randriamalala, Edouard; Caillot, Denis; Lioure, Bruno; Devidas, Alain; Mossafa, Hossein; Preudhomme, Claude; Ifrah, Norbert; Dombret, Hervé; Macintyre, Elizabeth; Asnafi, Vahid

2014-03-20

366

Impacts of waterlogging and salinity on puccinellia ( Puccinellia ciliata ) and tall wheatgrass ( Thinopyrum ponticum ): zonation on saltland with a shallow water-table, plant growth, and Na + and K + concentrations in the leaves  

Microsoft Academic Search

This paper focuses on the causes of zonation on agricultural land affected by secondary salinity between two halophytic grasses,\\u000a puccinellia (Puccinellia ciliata Bor. cv. Menemen) and tall wheatgrass (Thinopyrum ponticum (Podp.) Z.-W. Liu & R.R.-C. Wang cv. Tyrrell). We hypothesized that the differences in zonation of puccinellia and tall wheatgrass\\u000a were caused primarily by differences in the tolerance of these

Sommer Jenkins; Edward G. Barrett-Lennard; Zed Rengel

2010-01-01

367

Cetacean Strategies.  

ERIC Educational Resources Information Center

Suggested are activities about whales for children in schools not near the ocean. Activities designed to pique students' interest in whales and to investigate the size, breathing, buoyancy, and feeding strategies of whales are discussed. (CW)

Gilliland, Denise DelGrosso

1991-01-01

368

A nano-graphite-DNA hybrid sensor for magnified fluorescent detection of mercury(II) ions in aqueous solution.  

PubMed

In this communication, we present a nano-graphite-DNA hybrid sensor for fluorescent detection of mercury(II) ions in aqueous solution for the first time. Furthermore, an amplification strategy based on nano-graphite for Hg(2+) detection by using DNase I was demonstrated. The proposed amplified assay was simple and cost-effective with a limit of detection (LOD) for Hg(2+) of 0.5 nM, which was about 20-fold lower than that of traditional unamplified homogeneous assays. We further demonstrated its practical application to detect Hg(2+) in a real sample. PMID:24555179

Wei, Yin; Li, Bianmiao; Wang, Xu; Duan, Yixiang

2014-04-01

369

A newly defined envelope function for nano particles - carbon nano tube  

Microsoft Academic Search

Dangling bonds on CNT (Carbon NanoTube) surface induce the spurious surface states. These dangling bonds can be bonded by incoming nano particles which is associated wave function with different characters (localization at the surface) in respect to real quantized states. When the translational symmetry is broken, we can limit the calculation to an area like a ring or a super

F. M. Nakhaei; A. Bahari

2009-01-01

370

Nano Surface Generation in Grinding Process using Carbon Nano Tube with Lubricant Mixture  

Microsoft Academic Search

Carbon nano tubes have been of great interest, both from a fundamental point of view and for future application. The most eye catching features of these structures are their mechanical, optical and chemical characteristics, which open a way to future application. For commercial applications large quantities of purified nanotubes are needed. Carbon nano tubes of different types can be produced

S. Prabhu; B. K. Vinayagam

371

In situ microscopy of rapidly heated nano-Al and nano-Al/WO3 thermites  

NASA Astrophysics Data System (ADS)

The initiation and reaction mechanism of nano-Al and nano-Al thermites in rapid heating environments is investigated in this work. A semiconductor-based grid/stage was used, capable of in situ heating of a sample from room temperature to 1473 K, and at a rate of 106 K/s, inside an electron microscope. Nano-Al was rapidly heated in a transmission electron microscope, and before and after images indicate that the aluminum migrates through the shell, consistent with a diffusion-based mechanism. A nano-Al/WO3 composite was then heated in a scanning electron microscope. The results indicate that a reactive sintering mechanism is occurring for the nano-Al/WO3 thermite, as the products are found to be in surface contact and significantly deformed after the heating pulse.

Sullivan, Kyle T.; Chiou, Wen-An; Fiore, Richard; Zachariah, Michael R.

2010-09-01

372

Generation of Nano-Catalyst Particles by Spinodal Nano-Decomposition in Perovskite  

NASA Astrophysics Data System (ADS)

A new mechanism of nano-catalyst generation based on the spinodal nano-decomposition in self-regenerating perovskite catalysts for automotive-emissions control is proposed. To demonstrate existence of the spinodal nano-decomposition in real perovskite catalysts, we performed first-principles calculations to evaluate the free energy of La(Fe1-xPdx)O3 and La(Fe1-xRhx)O3. The result indicates appearance of a spinodal region in the phase diagram of each material. Formation of nano-catalyst particles in the perovskite host matrix is crucial for the self-regeneration of perovskite catalyst. Based on the spinodal nano-decomposition model, possible materials are designed for new three-way catalyst with no contents of precious metal.

Kizaki, Hidetoshi; Kusakabe, Koichi; Nogami, Soichiro; Katayama-Yoshida, Hiroshi

2008-10-01

373

Iodinated NanoClusters as an inhaled CT contrast agent for lung visualization  

PubMed Central

Improvements to contrast media formulations may be an effective way to increase the accuracy and effectiveness of thoracic computed tomography (CT) imaging in disease evaluation. To achieve contrast enhancement in the lungs, a relatively large localized concentration of contrast media must be delivered. Inhalation offers a non-invasive alternative to intrapleural injections for local lung delivery, but effective aerosolization may deter successful imaging strategies. Here, NanoCluster technology was applied to N1177, a diatrizoic acid derivative, to formulate low density nanoparticle agglomerates with aerodynamic diameters ? 5 µm. Excipient-free N1177 NanoCluster powders were delivered to rats by insufflation or inhalation and scanned using CT up to 2 h post dose. CT images after inhalation showed a ~120 HU contrast increase in the lungs, which was more than sufficient contrast for thoracic CT imaging. Lung tissue histology demonstrated that N1177 NanoClusters did not damage the lungs. NanoCluster particle engineering technology offers a novel approach to safely and efficiently disseminate high concentrations of contrast agents to the lung periphery. PMID:20575527

Aillon, Kristin L.; El-Gendy, Nashwa; Norenberg, Jeffery P.; McDonald, Jacob; Dennis, Connor; Berkland, Cory

2014-01-01

374

Interactions of neurons with topographic nano cues affect branching morphology mimicking neuron-neuron interactions.  

PubMed

We study the effect of topographic nano-cues on neuronal growth-morphology using invertebrate neurons in culture. We use photolithography to fabricate substrates with repeatable line-pattern ridges of nano-scale heights of 10-150 nm. We plate leech neurons atop the patterned-substrates and compare their growth pattern to neurons plated atop non-patterned substrates. The model system allows us the analysis of single neurite-single ridge interactions. The use of high resolution electron microscopy reveals small filopodia processes that attach to the line-pattern ridges. These fine processes, that cannot be detected in light microscopy, add anchoring sites onto the side of the ridges, thus additional physical support. These interactions of the neuronal process dominantly affect the neuronal growth direction. We analyze the response of the entire neuronal branching tree to the patterned substrates and find significant effect on the growth patterns compared to non-patterned substrates. Moreover, interactions with the nano-cues trigger a growth strategy similarly to interactions with other neuronal cells, as reflected in their morphometric parameters. The number of branches and the number of neurites originating from the soma decrease following the interaction demonstrating a tendency to a more simplified neuronal branching tree. The effect of the nano-cues on the neuronal function deserves further investigation and will strengthen our understanding of the interplay between function and form. PMID:22572872

Baranes, Koby; Kollmar, Davida; Chejanovsky, Nathan; Sharoni, Amos; Shefi, Orit

2012-08-01

375

Three-dimensional propagation characteristics of the upward connecting leaders in six negative tall-object flashes in Guangzhou  

NASA Astrophysics Data System (ADS)

Six downward negative flashes terminated on tall structures in Guangzhou are analyzed. The three-dimensional (3-D) lightning channels are reconstructed from dual-station optical observations. For each reconstructed 3-D upward connecting leader (UCL) channel, its 3-D length and speed are calculated. The 3-D length values of the six positive UCLs range from 180 to 818 m. There are 38 3-D speed values which are calculated combining the 3-D UCL channel and the high-speed images for the six UCLs. The 3-D speed values range from 0.8 to 14.3 × 105 m s- 1 and four of them (11%, 4/38) are on the order of 106 m s- 1. For comparison, the corresponding two-dimensional (2-D) parameters are calculated using the single-station high-speed images. The values of the 2-D length and 2-D speed range from 147 to 610 m and 0.3 to 10.6 × 105 m s- 1, respectively. From the statistical analysis, we determine that the average value of the 3-D speed is 1.3 times that of the 2-D speed. When the time is approaching the return stroke (RS), the propagation speed of the UCL is increasing. All of the four 3-D speed values on the order of 106 m s- 1 occur less than 0.2 ms prior to the RS. When the 3-D length is shorter than 300 m, 77% (20/26) of the corresponding 3-D speed values are smaller than 5 × 105 m s- 1. When the 3-D length is longer than 300 m or the UCL tip height is higher than 650 m, all of the corresponding 3-D speed values are faster than 5 × 105 m s- 1.

Gao, Yan; Lu, Weitao; Ma, Ying; Chen, Luwen; Zhang, Yang; Yan, Xu; Zhang, Yijun

2014-11-01

376

Endophyte-mediated resistance to black cutworm as a function of plant cultivar and endophyte strain in tall fescue.  

PubMed

To improve Neotyphodium endophyte-mediated resistance to black cutworm Agrotis ipsilon (Hufnagel) (BCW), a series of experiments was conducted by using several different cultivars of tall fescue, Schedonorus arundinaceus (Schreb.) Dumort. in combination with several different haplotypes of the endophyte Neotyphodium coenophialum (Morgan-Jones & Gams) (plant cultivar × endophyte haplotype = plant line), each producing unique alkaloid profiles. BCW settling response, survival at 5 and 10 d, and larval biomass varied significantly among plant lines. In general, greater variation BCW performance was observed within a single plant cultivar infected with different endophyte haplotypes than among different plant cultivars infected with the same endophyte haplotype, but comparisons among the former were far more numerous. Although five endophyte-mediated alkaloids representing three alkaloid classes were quantified in the plants, the pyrrolizidine alkaloid N-acetyl norloline was consistently the single best predictor of BCW performance. BCW settling response, 5-d survival, and 10-d survival decreased as levels of the alkaloid N-acetyl norloline increased. The same three response variables also decreased with increasing levels of peramine, but increased with increasing levels of ergovaline. Minor variation in endophyte infection levels occurring among infected plant lines had no significant influence on BCW performance. Results indicate a potentially important role for N-acetyl norloline and peramine in providing resistance to black cutworm whereas ergovaline appears to be much less important. Therefore, endophyte haplotypes expressing high levels of N-acetyl norloline and peramine may be of particular importance for developing 'friendly' endophyte-enhanced turf and pasture grasses that resist challenging lepidopteran pests, although remaining safe for wildlife and grazing mammals. PMID:22251642

Baldauf, Michael W; Mace, Wade J; Richmond, Douglas S

2011-06-01

377

Increased searching and handling effort in tall swards lead to a Type IV functional response in small grazing herbivores.  

PubMed

Understanding the functional response of species is important in comprehending the species' population dynamics and the functioning of multi-species assemblages. A Type II functional response, where instantaneous intake rate increases asymptotically with sward biomass, is thought to be common in grazers. However, at tall, dense swards, food intake might decline due to mechanical limitations or if animals selectively forage on the most nutritious parts of a sward, leading to a Type IV functional response, especially for smaller herbivores. We tested the predictions that bite mass, cropping time, swallowing time and searching time increase, and bite rate decreases with increasing grass biomass for different-sized Canada geese (Branta canadensis) foraging on grass swards. Bite mass indeed showed an increasing asymptotic relationship with grass biomass. At high biomass, difficulties in handling long leaves and in locating bites were responsible for increasing cropping, swallowing, and searching times. Constant bite mass and decreasing bite rate caused the intake rate to decrease at high sward biomass after reaching an optimum, leading to a Type IV functional response. Grazer body mass affected maximum bite mass and intake rate, but did not change the shape of the functional response. As grass nutrient contents are usually highest in short swards, this Type IV functional response in geese leads to an intake rate that is maximised in these swards. The lower grass biomass at which intake rate was maximised allows resource partitioning between different-sized grazers. We argue that this Type IV functional response is of more importance than previously thought. PMID:21221651

Heuermann, Nicol; van Langevelde, Frank; van Wieren, Sipke E; Prins, Herbert H T

2011-07-01

378

Comparison of ground and satellite based measurements of the fraction of photosynthetically active radiation intercepted by tall-grass prairie  

SciTech Connect

The fraction of photosynthetically active radiation intercepted by vegetation, F(sub ipar) is an important parameter for modeling the interactions between the land-surface and atmosphere and for estimating vegetation biomass productivity. This study was, therefore, an integral part of FIFE. The specific purpose of this experiment was to find out how well definitive measurements of F(sub ipar) on the ground relate to near-ground and satellite based spectral reflectance measurements. Concurrent measurements of F(sub ipar) and ground, helicopter, and satellite based reflectance measurements were taken at thirteen tall-grass prairie sites within the FIFE experimental area. The sites were subjected to various combinations of burning and grazing managements. The ground and helicopter based reflectance measurements were taken on the same day or few days from the time of the overpass of LANDSAT and SPOT satellites. Ground-based reflectance measurements and sun photometer readings taken at the times of the satellite overpasses were used to correct for atmospheric attenuation. Hand-held radiometer spectral indices were strongly correlated with helicopter and satellite based values (r = 0.94 for helicopter, 0.93 for LANDSAT Thematic Mapper, and 0.86 for SPOT). However, the ground, helicopter, and satellite based normalized difference spectral vegetation indices showed low sensitivity to changes in F(sub ipar). Reflectance measurements were only moderately well correlated with measurements of F(sub ipar) (r = 0.82 for hand-held radiometer, 0.84 for helicopter measurements, and 0.75 for the LANDSAT Thematic Mapper and SPOT). Improved spectral indices which can compensate for site differences are needed in order to monitor F(sub ipar) more reliably. 12 refs.

Demetriades-shah, T.H.; Kanemasu, E.T.; Flitcroft, I.D.; Su, H. (Georgia Univ., Griffin (United States) Kansas State Univ., Manhattan (United States))

1992-11-01

379

The structure of turbulence near a tall forest edge: the backward-facing step flow analogy revisited.  

PubMed

Flow disturbances near tall forest edges are receiving significant attention in diverse disciplines including ecology, forest management, meteorology, and fluid mechanics. Current theories suggest that near a forest edge, when the flow originates from a forest into a large clearing, the flow retains its forest canopy turbulence structure at the exit point. Here, we propose that this framework is not sufficiently general for dense forested edges and suggest that the flow shares several attributes with backward-facing step (BFS) flow. Similar analogies, such as rotor-like circulations, have been proposed by a number of investigators, though the consequences of such circulations on the primary terms in the mean momentum balance at the forest clearing edge have rarely been studied in the field. Using an array of three triaxial sonic anemometers positioned to measure horizontal and vertical gradients of the velocity statistics near a forest edge, we show that the flow structure is more consistent with an intermittent recirculation pattern, rather than a continuous rotor, whose genesis resembles the BFS flow. We also show that the lateral velocity variance, v'2, is the moment that adjusts most slowly with downwind distance as the flow exits from the forest into the clearing. Surprisingly, the longitudinal and vertical velocity variances (u'2 and w'2) at the forest edge were comparable in magnitude to their respective values at the center of a large grass-covered forest clearing, suggesting rapid adjustment at the edge. Discussions on how the forest edge modifies the spectra and co-spectra of momentum fluxes, effective mixing length, and static pressure are also presented. PMID:18767620

Detto, Matteo; Katul, Gabriel G; Siqueira, Mario; Juang, Jehn-Yih; Stoy, Paul

2008-09-01

380

Bioinspired synthesis of hierarchically micro/nano-structured CuI tetrahedron and its potential application as adsorbent for Cd(II) with high removal capacity.  

PubMed

An environment friendly bioinspired strategy for synthesizing hierarchically micro/nano-structured CuI tetrahedron has been developed by combining the stabilization and the reduction performances of l-tryptophan together. A possible growth mechanism of such hierarchical tetrahedron is tentatively proposed. Remarkably, such CuI tetrahedron is found to possess high removal capacity for poisonous Cd(II) ions, 136.3mg/g, and ideal reusability. This is ascribed to the hierarchical micro/nano-structure and chemical adsorption mechanism, which shows great advantages over the traditional nano-scaled adsorbents. These interesting results stand out the promising applications of such hierarchically micro/nano-structured materials in environment. It is also a good example for the organic combination of green chemistry and nanotechnologies for the treatment of contaminated water. PMID:22305599

Gao, Shuyan; Yang, Jianmao; Li, Zhengdao; Jia, Xiaoxia; Chen, Yanli

2012-04-15

381

Rotation motion of designed nano-turbine.  

PubMed

Construction of nano-devices that can generate controllable unidirectional rotation is an important part of nanotechnology. Here, we design a nano-turbine composed of carbon nanotube and graphene nanoblades, which can be driven by fluid flow. Rotation motion of nano-turbine is quantitatively studied by molecular dynamics simulations on this model system. A robust linear relationship is achieved with this nano-turbine between its rotation rate and the fluid flow velocity spanning two orders of magnitude, and this linear relationship remains intact at various temperatures. More interestingly, a striking difference from its macroscopic counterpart is identified: the rotation rate is much smaller (by a factor of ~15) than that of the macroscopic turbine with the same driving flow. This discrepancy is shown to be related to the disruption of water flow at nanoscale, together with the water slippage at graphene surface and the so-called "dragging effect". Moreover, counterintuitively, the ratio of "effective" driving flow velocity increases as the flow velocity increases, suggesting that the linear dependence on the flow velocity can be more complicated in nature. These findings may serve as a foundation for the further development of rotary nano-devices and should also be helpful for a better understanding of the biological molecular motors. PMID:25068725

Li, Jingyuan; Wang, Xiaofeng; Zhao, Lina; Gao, Xingfa; Zhao, Yuliang; Zhou, Ruhong

2014-01-01

382

Advances in nano drugs for cancer chemotherapy.  

PubMed

In spite of some medications, millions of peoples are dying every year due to cancer. Additionally, the survival patients suffer from various serious side effects due to the use of available anti-neoplastic medicines. The development of nanoparticles based drugs is seems to be effective providing low side effects and targeted action on cancer cells. The present article describes the state-of-art of nano drugs in cancer chemotherapy. The nano drugs are targeted selective and specific towards tumors only resulting into better treatment. The important molecules used for preparation nano drugs are cisplatin, carboplatin, bleomycin, 5-fluorouracil, doxorubicin, dactinomycin, 6-mercaptopurine, paclitaxel, topotecan, vinblastin and etoposide etc. The most commonly used materials for preparing nanoparticles carriers are dendrimers, polymer, liposome, micelles, inorganic, organic nanoparticles etc. A survey was carried out on the drugs available in the market and given in tabular form. However, the commonly used nano drugs till date are liposome dendrimer and some other materials based nanoparticles. Attempts have been made to explain mechanism of action of nano drugs. The future perspectives have also been highlighted in to the conclusion part. PMID:21158724

Ali, Imran; Rahis-Uddin; Salim, K; Rather, Mohmad A; Wani, Waseem A; Haque, Ashanul

2011-02-01

383

Rotation Motion of Designed Nano-Turbine  

NASA Astrophysics Data System (ADS)

Construction of nano-devices that can generate controllable unidirectional rotation is an important part of nanotechnology. Here, we design a nano-turbine composed of carbon nanotube and graphene nanoblades, which can be driven by fluid flow. Rotation motion of nano-turbine is quantitatively studied by molecular dynamics simulations on this model system. A robust linear relationship is achieved with this nano-turbine between its rotation rate and the fluid flow velocity spanning two orders of magnitude, and this linear relationship remains intact at various temperatures. More interestingly, a striking difference from its macroscopic counterpart is identified: the rotation rate is much smaller (by a factor of ~15) than that of the macroscopic turbine with the same driving flow. This discrepancy is shown to be related to the disruption of water flow at nanoscale, together with the water slippage at graphene surface and the so-called ``dragging effect''. Moreover, counterintuitively, the ratio of ``effective'' driving flow velocity increases as the flow velocity increases, suggesting that the linear dependence on the flow velocity can be more complicated in nature. These findings may serve as a foundation for the further development of rotary nano-devices and should also be helpful for a better understanding of the biological molecular motors.

Li, Jingyuan; Wang, Xiaofeng; Zhao, Lina; Gao, Xingfa; Zhao, Yuliang; Zhou, Ruhong

2014-07-01

384

Scanning Electron Microscope (FEI Nova NanoSEM 2300)  

E-print Network

Scanning Electron Microscope (FEI Nova NanoSEM 2300) September 2010 #12;FEI Nova NanoSEM 2300, the microscope can be seriously damaged. #12;Operating Parameters Field-Free (ETD): Use for imaging large areas

Subramanian, Venkat

385

Nano, Quantum, and Statistical Mechanics and Thermodynamics: Educational Sites  

NSDL National Science Digital Library

This collection of links provides access to web sites associated with nano, quantum, and statistical mechanics and thermodynamics. The links are arranged by type: basic principles (including classical thermodynamics), nano, quantum, and statistical mechanics, mathematical techniques, applications, and references.

386

Superconducting Wires Enabled by Nanodots wins Nano50TM Award  

E-print Network

Superconducting Wires Enabled by Nanodots wins Nano50TM Award HTS Wires Enabled via 3D Self. · Awarded the Nano 50TM Award from Nanotech Briefs® Magazine for technology. Developers: · A. Goyal S. Kang

387

Carbon nano-relays for low power switching  

E-print Network

In this thesis two unique carbon based nanoelectromechanical switches or carbon nano-relays are demonstrated as a toolkit for investigating NEMs based low power switching. The first is a vertical carbon nano-relay, consisting ...

Milaninia, Kaveh Mehdi

2009-01-01

388

Morphology and antifungal effect of nano-ZnO and nano-Pd-doped nano-ZnO against Aspergillus and Candida.  

PubMed

The present work was aimed to study the activity of nano-particulated ZnO and nano Pd doped nano-ZnO against Aspergillus and Candida species, commonly contaminating the water supply systems. Micro-ZnO was purchased from the market (Aldrich, USA) while nano ZnO were synthesized using sole gel and precipitation methods and their morphology was determined using XRD and TEM techniques. The average grain size of nano-ZnO estimated by these techniques was 30 nm and 20 nm, respectively. The doping of nano-ZnO with 5 % Pd was achieved by a thermal decomposition method and its morphology; as characterized by XRD, TEM and FESEM techniques; gave an average grain size of 35 nm. Serial dilutions of nano-ZnO doped with 5 % Pd, pure nano-ZnO and micro-ZnO (as a control) were prepared from 10 mg/mL stock solution of each in dermasel agar (OXOID), inoculated with standard strains of Candida albicans and Aspergillus niger and incubated at 37°C for 24 and 48 hours, respectively. Their antimicrobial effect was compared by the minimal inhibitory concentration (MIC), determined as the dilution giving a negligible growth of microorganism. Nano-ZnO doped with 5 % nano-Pd, pure nano-ZnO and micro-ZnO, showed antifungal activity against Aspergilus niger with an MIC of 1.25, 2.5 and 5mg/mL, respectively. However, Candida albicans yeasts were relatively resistant to these compounds, with an MIC of 2.5, 5 and 10 mg/mL for Pd doped nano-ZnO, nano-ZnO and micro-ZnO, respectively. Thus nano-ZnO was twice as potent in killing Aspergillus, as compared to its non-nano-counterpart and loading of nano-ZnO with 5 % nano-Pd further increased its activity, four times that of micro-ZnO. Further investigations are needed to confirm the potential use of nano-ZnO and its doping with nano-Pd in the treatment of water supply systems and food preservation. PMID:22571529

Gondal, Mohammed A; Alzahrani, Alhusain J; Randhawa, Mohammad A; Siddiqui, Mohammad N

2012-01-01

389

Effects of modified tall oil versus a commercial source of conjugated linoleic acid and increasing levels of modified tall oil on growth performance and carcass characteristics of growing-finishing pigs.  

PubMed

Two experiments were conducted to evaluate the effects of conjugated linoleic acid (CLA)-enriched feed additives for swine. These additives included a source of CLA that was commercially available (CLA-60) and modified tall oil (MTO). Experiment 1 used 36 barrows (initially 37.6+/-2.8 kg) to compare the effects of CLA-60 and MTO on growth performance and carcass characteristics of finishing pigs. The corn-soybean meal diets contained .50% soybean oil (control), .50% CLA-60, or .50% MTO. Pigs fed CLA-60 had less (P = .03) ADG from 37.6 to 72.6 kg than the control pigs; otherwise, pigs fed either CLA-60 or MTO had growth performance similar (P > .15) to that of the control pigs. Pigs fed MTO grew faster (P = .03) and consumed more feed (P = .10) over the duration of the experiment (37.6 to 106.4 kg) than pigs fed CLA-60. Dietary treatment did not affect (P > .15) plasma triglycerides or carcass characteristics, but pigs fed either MTO or CLA-60 had greater saturation of fatty acids in the adipose tissue at the 10th rib than pigs fed the control diet. Experiment 2 used 80 barrows (initially 33.4+/-2.2 kg) to examine the effects of increasing levels of MTO on growth performance and carcass characteristics of finishing pigs. The corn-soybean meal diet contained 1% cornstarch, which was replaced with MTO to give dietary levels of .25, .50, or 1.00% MTO. Dietary treatment did not affect (P > .15) growth performance. Feeding increasing levels of MTO quadratically decreased (P = .02) average backfat thickness and longissimus muscle drip loss (P = .04) and quadratically increased longissimus muscle area (P = .07) and percentage lean (P = .03). Feeding MTO tended to increase belly firmness (P < .10) compared with pigs fed the control diet. These traits appeared to be optimized with .50% MTO. In summary, pigs fed MTO had greater ADG, ADFI, and ending BW than pigs fed CLA-60. Feeding MTO does not appear to affect growth performance but improves carcass lean content and may additionally improve some aspects of meat quality in growing-finishing pigs. PMID:10985411

O'Quinn, P R; Nelssen, J L; Goodband, R D; Unruh, J A; Woodworth, J C; Smith, J S; Tokach, M D

2000-09-01

390

Applications of MEMS actuators in micro\\/nano robotic manipulators  

Microsoft Academic Search

Micro\\/nano robotic manipulators have the ability to position and orient objects at the micro\\/nano scales and are capable of performing very small motion with high resolution. The performances of micro\\/nano robotic manipulators greatly influence on the reliability and efficiency of the entire system. Furtherly, the positioning and orientation of micro\\/nano robotic manipulators depend largely on their actuators. So the miniaturized

Liwei Li

2010-01-01

391

Dynamics and energy dissipation of nano-graphite mechanical devices  

Microsoft Academic Search

Controllable mechanical motion of nano-structures holds great interests because of their applications in the nano-electromechanical systems (NEMS). One of the novel models proposed was the nano-graphitic materials based devices, where planar or cylindrical graphene layers act as moving parts and the motion is managed by the van der Waals force between them. Comparing with the multi-walled carbon nanotubes, nano-graphite flakes

Zhiping Xu

2008-01-01

392

Abrasion resistance of concrete containing nano-particles for pavement  

Microsoft Academic Search

The abrasion resistance of concrete containing nano-particles for pavement is experimentally studied. Both nano-TiO2 and nano-SiO2 are, respectively, employed to be as the additives. For comparison, the abrasion resistance of plain concrete and the concrete containing polypropylene (PP) fibers is also experimentally studied in this work. The test results indicate that the abrasion resistance of concretes containing nano-particles and PP

Hui Li; Mao-hua Zhang; Jin-ping Ou

2006-01-01

393

Coping Strategies.  

ERIC Educational Resources Information Center

Coping with the high cost of teaching chemistry, content of organic chemistry, instructional strategies, and approaches in dealing with the changing student population (urban blacks/hispanics, handicapped, and other nontraditional students) are among the topics discussed in 19 papers presented at the Seventh Biennial Conference on Chemical…

Journal of Chemical Education, 1983

1983-01-01

394

Questioning Strategies  

NSDL National Science Digital Library

In this brief article from the Charles A. Dana Center at the University of Texas at Austin the best practices of questioning strategies are explained. The author illustrates the difference between an open and a closed question and provides examples of the five categories of questions that teachers should be asking. A bibliography of additional resources is included for further study.

2012-01-01

395

3D nano-structures for laser nano-manipulation Gediminas Seniutinas1,2, Lorenzo Rosa*1,2, Gediminas Gervinskas1,2,  

E-print Network

534 3D nano-structures for laser nano-manipulation Gediminas Seniutinas1,2, Lorenzo Rosa*1-Institut. License and terms: see end of document. Abstract The resputtering of gold films from nano-holes defined of the nano-holes. The extraordinary transmission through the patterns of such nano-wells was investigated

Boyer, Edmond

396

Micro and Nano Systems for Space Exploration  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the use of micro and nano systems in Space exploration. Included are: an explanation of the rationales behind nano and micro technologies for space exploration, a review of how the devices are fabricated, including details on lithography with more information on Electron Beam (E-Beam) lithography, and X-ray lithography, a review of micro gyroscopes and inchworm Microactuator as examples of the use of MicroElectoMechanical (MEMS) technology. Also included is information on Carbon Nanotubes, including a review of the CVD growth process. These micro-nano systems have given rise to the next generation of miniature X-ray Diffraction, X-ray Fluorescence instruments, mass spectrometers, and terahertz frequency vacuum tube oscillators and amplifiers, scanning electron microscopes and energy dispersive x-ray spectroscope. The nanotechnology has also given rise to coating technology, such as silicon nanotip anti-reflection coating.

Manohara, Harish

2007-01-01

397

Fibers from polypropylene\\/nano carbon fiber composites  

Microsoft Academic Search

Fibers from polypropylene and polypropylene\\/vapor grown nano carbon fiber composite have been spun using conventional melt spinning equipment. At 5wt% nano carbon fiber loading, modulus and compressive strength of polypropylene increased by 50 and 100%, respectively, and the nano carbon fibers exhibited good dispersion in the polypropylene matrix as observed by scanning electron microscopy.

Satish Kumar; Harit Doshi; Mohan Srinivasarao; Jung O Park; David A Schiraldi

2002-01-01

398

Haptic Simulation for Micro/Nano-Scale Optical Fiber Assembly  

E-print Network

Haptic Simulation for Micro/Nano-Scale Optical Fiber Assembly Qi Luo and Jing Xiao IMI Lab on the modeling and simulation of the optical fiber assembly. In this paper, the interaction forces in the micro/nano for designing leaning- based controller for automated micro/nano-scale optical fiber assembly. I. INTRODUCTION

Xiao, Jing

399

Interactive Nano-visualization in Science & Engineering Education  

NSDL National Science Digital Library

This project has developed learning resources that include nano-scale science and technology into the high school and introductory college curricula. Resources include an online scanning-probe microscope, a wide range of images and animations illustrating material and chemical properties on the nano-scale, and online learning modules on material science and nano-scale biological science.

Ramakrishna, B. L.

2005-03-16

400

Micro et Nano Physique Cours 1 : les principes de la  

E-print Network

Micro et Nano Physique (MNP) Cours 1 : les principes de la mécanique quantique (approche conceptuelle) #12;Micro et nano physique (MNP)page 1 Pourquoi un cours sur la physique microscopique ? · Une fondamentaux à la base des technologies du numérique #12;Micro et nano physique (MNP)page 2 Organisation de l

Rioul, Olivier

401

Nano-Spintronics 2010 Spin-Orbit Effects  

E-print Network

Nano-Spintronics 2010 Spin-Orbit Effects in Semiconductors with Reduced Dimensions Thomas Schäpers Institut für Bio- und Nanosysteme (IBN-1) MitgliedderHelmholtz-Gemeinschaft #12;Nano-Spintronic Bad Honnef by a gate (Rashba effect) #12;Nano-Spintronic Bad Honnef, 2010 Institut für Bio- und Nanosysteme (IBN-1

Duisburg-Essen, Universität

402

Understanding nano-materials from first principles Leeor Kronik  

E-print Network

Understanding nano-materials from first principles Leeor Kronik Department of Materials and Interfaces, Weizmann Institute of science, Rehovoth 76100 Nano-sized materials often exhibit exciting new traditional solid-state physics models are applicable to the intermediate nano- size range. As a result, first

Adler, Joan

403

Nano-Manufacturing While nanotechnology promises to revolutionize everything from  

E-print Network

Nano-Manufacturing While nanotechnology promises to revolutionize everything from energy production futuristic systems will remain science fiction without practical and scalable nano-manufacturing capabilities. Researchers at the University of Maryland's NanoCenter have the manufacturing capabilities needed for turning

Hill, Wendell T.

404

Nano Research Kinetics of Molecular Recognition Mediated Nanoparticle  

E-print Network

Nano Research Kinetics of Molecular Recognition Mediated Nanoparticle Self-Assembly Chinmay Soman1 the streptavidin-biotin interaction [9] 0078 Nano Res (2009) 2: 78 84 DOI 10.1007/s12274-009-9005-z Research Article #12;79Nano Res (2009) 2: 78 84 are incubated with specific antigens in a physiological buffer

405

NANO-INDENTATION OF COPPER THIN FILMS ON SILICON SUBSTRATES  

E-print Network

NANO-INDENTATION OF COPPER THIN FILMS ON SILICON SUBSTRATES S. Suresh1 , T.-G. Nieh2 and B.W. Choi2: Mechanical properties; Nano-indentation; Thin films; Copper; Dislocations Introduction Indentation methods films on substrates (e.g., [2,3]) using instrumented indentation. Nano-indentation studies of thin films

Suresh, Subra

406

Nano-scale Sensor Networks for Chemical Eisa Zarepour1  

E-print Network

Nano-scale Sensor Networks for Chemical Catalysis Eisa Zarepour1 Mahbub Hassan1 Chun Tung Chou1- searchers are now investigating the viability of nano-scale sensor networks (NSNs), which are formed natural gas to liquid fuel. Given that reliable wireless communi- cation at nano-scale is at very early

New South Wales, University of

407

Chapter 2 Simulation of Single Walled Carbon Nano Tubes SWNT  

E-print Network

13 Chapter 2 Simulation of Single Walled Carbon Nano Tubes SWNT 2.1 Introduction Carbon nanotubes, mechanical and vibrational properties of single-walled carbon nano tubes SWNT," G. Gao, T. Cagin, and W properties of single-walled carbon nano tubes with di erent radius and chirality armchair n, n, chiral 2n, n

Goddard III, William A.

408

Self Assembly of Nano Metric Metallic Particles for Realization of Photonic and Electronic Nano Transistors  

E-print Network

Abstract: In this paper, we present the self assembly procedure as well as experimental results of a novel method for constructing well defined arrangements of self assembly metallic nano particles into sophisticated nano structures. The self assembly concept is based on focused ion beam (FIB) technology, where metallic nano particles are self assembled due to implantation of positive gallium ions into the insulating material (e.g., silica as in silicon on insulator wafers) that acts as intermediary layer between the substrate and the negatively charge metallic nanoparticles.

unknown authors

2010-01-01

409

Tall order in Arizona  

SciTech Connect

A 7-year, $470 million project to retrofit scrubber units on a coal-fired power plant is summarized. The scrubbers will be retooled at the 2250-MW Navajo Generating Station in a clean air agreement between the US federal government and Salt River Project. A forced oxidation flue gas desulfurization system was selected for the retrofit; design and construction aspects are summarized in the article. Negotiations between the US Environmental Protection Agency, the Environmental Defense Fund, and the Navajo Nation leading to the retrofit action are also outlined.

Wright, A.G.

1997-03-10

410

How Tall Are We?  

NSDL National Science Digital Library

Students measure each other's height using large building blocks, then visit a 2nd and a 4th grade class to measure those students. They can also measure adults in the school community. Measurement data is tallied and may be displayed, in an extended activity, on age-appropriate bar graphs (paper cut-outs of miniature building blocks glued on paper to form a bar graph), comparing the different age groups. The activities that comprise this lesson help students develop the concepts and vocabulary to describe, in a non-ambiguous way, how height changes as children get older. The extended introduction to graphing provides an important foundation for measurement, as well as for creating and interpreting graphs in future years.

Hebrank, Mary R.

2004-01-01

411

How Tall Are We?  

NSDL National Science Digital Library

Kindergartners measure each others' heights using large building blocks, then visit a second- and a fourth-grade class to measure those students' heights. They also measure adults in the school community. Students display the collected data in bar graphs made from paper cut-outs of miniature building blocks glued on paper, comparing the different age groups. The associated activity for this lesson helps students develop the concepts and vocabulary to describe, in a non-ambiguous way, how height changes as children age. The introduction to graphing provides an important foundation for both creating and interpreting graphs in future years.

Engineering K-Phd Program

412

Wafer-scale aluminum nano-plasmonics  

NASA Astrophysics Data System (ADS)

The design, characterization, and optical modeling of aluminum nano-hole arrays are discussed for potential applications in surface plasmon resonance (SPR) sensing, surface-enhanced Raman scattering (SERS), and surface-enhanced fluorescence spectroscopy (SEFS). In addition, recently-commercialized work on narrow-band, cloaked wire grid polarizers composed of nano-stacked metal and dielectric layers patterned over 200 mm diameter wafers for projection display applications is reviewed. The stacked sub-wavelength nanowire grid results in a narrow-band reduction in reflectance by 1-2 orders of magnitude, which can be tuned throughout the visible spectrum for stray light control.

George, Matthew C.; Nielson, Stew; Petrova, Rumyana; Frasier, James; Gardner, Eric

2014-09-01

413

Aligning carbon nano fibers using magnetic nanofluids  

NASA Astrophysics Data System (ADS)

Oleic acid coated magnetic nano particles and sodium dodecyl sulphate (SDS) coated carbon nano fibers are suspended in an aqueous medium. Under the application of very low magnetic field (˜500 Oe), the physically adsorbed magnetic nanoparticles with carbon nanofibers are spatially aligned. The external magnetic field aligns the magnetic moment of the particles and consequent body forces align the carbon nanofibers. This alignment is studied using a microscope attached with computer and using a capillary viscometry. This form of orientation may be very useful for various nanofluidics and nanoelectromechanical systems (NEMS).

Parmar, Mayur A.; Virpura, Hiral A.; Dave, Vishaka; Patel, Rajesh J.

2014-04-01

414

Olefin metathesis in nano-sized systems  

PubMed Central

Summary The interplay between olefin metathesis and dendrimers and other nano systems is addressed in this mini review mostly based on the authors’ own contributions over the last decade. Two subjects are presented and discussed: (i) The catalysis of olefin metathesis by dendritic nano-catalysts via either covalent attachment (ROMP) or, more usefully, dendrimer encapsulation – ring closing metathesis (RCM), cross metathesis (CM), enyne metathesis reactions (EYM) – for reactions in water without a co-solvent and (ii) construction and functionalization of dendrimers by CM reactions. PMID:21286399

Diallo, Abdou K; Gatard, Sylvain; Liang, Liyuan; Ornelas, Catia; Martinez, Victor; Mery, Denise; Ruiz, Jaime

2011-01-01

415

Flow and leakage characteristics of a sashless inclined air-curtain (sIAC) fume hood containing tall pollutant-generation tanks.  

PubMed

In many fume hood applications, pollutant-generation devices are tall. Human operators of a fume hood must stand close to the front of the hood and lift up their hands to reach the top opening of the tall tank. In this situation, it is inconvenient to access the conventional hood because the sash acts as a barrier. Also, the bluff-body wake in front of the operator's chest causes a problem. By using laser-assisted smoke flow visualization and tracer-gas test methods, the present study examines a sashless inclined air-curtain (sIAC) fume hood for tall pollutant-generation tanks, with a mannequin standing in front of the hood face. The configuration of the sIAC fume hood, which had the important element of a backward-inclined push-pull air curtain, was different from conventional configurations. Depending on suction velocity, the backward-inclined air curtain had three characteristic modes: straight, concave, and attachment. A large recirculation bubble covering the area--from the hood ceiling to the work surface--was formed behind the inclined air curtain in the straight and concave modes. In the attachment mode, the inclined air curtain was attached to the rear wall of the hood, about 50 cm from the hood ceiling, and bifurcated into up and down streams. Releasing the pollutants at an altitude above where the inclined air curtain was attached caused the suction slot to directly draw up the pollutants. Releasing pollutants in the rear recirculation bubble created a risk of pollutants' leaking from the hood face. The tracer-gas (SF6) test results showed that operating the sIAC hood in the attachment mode, with the pollutants being released high above the critical altitude, could guarantee almost no leakage, even though a mannequin was standing in front of the sashless hood face. PMID:24195536

Chen, Jia-Kun; Huang, Rong Fung; Hung, Wei-Lun

2013-01-01

416

Change in hydraulic properties and leaf traits of a tall rainforest tree species subjected to long-term throughfall exclusion in the perhumid tropics  

NASA Astrophysics Data System (ADS)

In a throughfall displacement experiment on Sulawesi, Indonesia, three 0.16 ha stands of a premontane perhumid rainforest were exposed to a two-year soil desiccation period that reduced the soil moisture in the upper soil layers beyond the conventional wilting point. About 25 variables, including leaf morphological and chemical traits, stem diameter growth and hydraulic properties of the xylem in the trunk and terminal twigs, were investigated in trees of the tall-growing tree species Castanopsis acuminatissima (Fagaceae) by comparing desiccated roof plots with nearby control plots. We tested the hypotheses that this tall and productive species is particularly sensitive to drought, and the exposed upper sun canopy is more affected than the shade canopy. Hydraulic conductivity in the xylem of terminal twigs normalised to vessel lumen area was reduced by 25%, leaf area-specific conductivity by 10-33% during the desiccation treatment. Surprisingly, the leaves present at the end of the drought treatment were significantly larger, but not smaller in the roof plots, though reduced in number (about 30% less leaves per unit of twig sapwood area), which points to a drought effect on the leaf bud formation while the remaining leaves may have profited from a surplus of water. Mean vessel diameter and axial conductivity in the outermost xylem of the trunk were significantly reduced and wood density increased, while annual stem diameter increment decreased by 26%. In contradiction to our hypotheses, (i) we found no signs of major damage to the C. acuminatissima trees nor to any other drought sensitivity of tall trees, and (ii) the exposed upper canopy was not more drought susceptible than the shade canopy.

Schuldt, B.; Leuschner, C.; Horna, V.; Moser, G.; Köhler, M.; Barus, H.

2010-11-01

417

Molecular cytogenetic study of 126 unselected T-ALL cases reveals high incidence of TCRbeta locus rearrangements and putative new T-cell oncogenes.  

PubMed

Chromosomal aberrations of T-cell receptor (TCR) gene loci often involve the TCRalphadelta (14q11) locus and affect various known T-cell oncogenes. A systematic fluorescent in situ hybridization (FISH) screening for the detection of chromosomal aberrations involving the TCR loci, TCRalphadelta (14q11), TCRbeta (7q34) and TCRgamma (7p14), has not been conducted so far. Therefore, we initiated a screening of 126 T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma cases and 19 T-ALL cell lines using FISH break-apart assays for the different TCR loci. Genomic rearrangements of the TCRbeta locus were detected in 24/126 cases (19%), most of which (58.3%) were not detected upon banding analysis. Breakpoints in the TCRalphadelta locus were detected in 22/126 cases (17.4%), whereas standard cytogenetics only detected 14 of these 22 cases. Cryptic TCRalphadelta/TCRbeta chromosome aberrations were thus observed in 22 of 126 cases (17.4%). Some of these chromosome aberrations target new putative T-cell oncogenes at chromosome 11q24, 20p12 and 6q22. Five patients and one cell line carried chromosomal rearrangements affecting both TCRbeta and TCRalphadelta loci. In conclusion, this study presents the first inventory of chromosomal rearrangements of TCR loci in T-ALL, revealing an unexpected high number of cryptic chromosomal rearrangements of the TCRbeta locus and further broadening the spectrum of genes putatively implicated in T-cell oncogenesis. PMID:16673021

Cauwelier, B; Dastugue, N; Cools, J; Poppe, B; Herens, C; De Paepe, A; Hagemeijer, A; Speleman, F

2006-07-01

418

Synoptic scale outbreak of self-initiated upward lightning (SIUL) from tall structures during the central U.S. blizzard of 1-2 February 2011  

NASA Astrophysics Data System (ADS)

major central U.S. winter cyclone on 1-2 February 2011 produced a band of high winds, up to 75 cm of snow, and numerous reports of thundersnow from Oklahoma into Ontario over a 26 h period. The National Lightning Detection Network (NLDN) recorded 282 flashes comprised of 1153 events which were >96% negative polarity. Hopes of imaging winter sprites associated with energetic positive cloud-to-ground events that sometimes accompany such winter storms did not materialize. However, the lack of lightning over the Great Lakes waters, plus media reports of numerous thundersnow events in downtown Chicago, prompted a detailed analysis of the NLDN data. This revealed that >93% of all lightning in the snow band was likely or possibly associated with self-initiated upward lightning (SIUL) events from a variety of tall, and some not so tall, structures. In addition to 43 events from two Chicago skyscrapers, many shorter structures were involved, including wind turbines (13.1% of the total) and transmission line towers (6.7%). Wind speeds for all events exceeded the 8 m s-1 minimum threshold associated with SIULs in Japanese winter lightning storms. Radar reflectivities at the event locations had a mean of 28 dBZ and were almost always <35 dBZ. While conventional radar displays suggested stratiform precipitation in the thundersnow region, detailed analysis of 3-D-gridded NMQ (National Mosaic and Multi-Sensor Quantitative Precipitation Estimation) radar reflectivity data confirmed elevated embedded cellular convection spanning the -10°C region associated with isentropic lifting above a frontal surface, evidence of noninductive charge generation sufficient to allow upward leader initiation from tall objects.

Warner, Tom A.; Lang, Timothy J.; Lyons, Walter A.

2014-08-01

419

Broiler litter application method and runoff timing effects on nutrient and Escherichia coli losses from tall fescue pasture.  

PubMed

The inability to incorporate manure into permanent pasture leads to the concentration of nutrients near the soil surface with the potential to be transported off site by runoff water. In this study, we used rainfall simulations to examine the effect of broiler chicken (Gallus gallus domesticus) litter application method and the runoff timing on nutrient and E. coli losses from tall fescue (Festuca arundinacea Schreb.) pasture on a Hartsells sandy loam soil (fine-loamy, siliceous, subactive, thermic Typic Hapludults)) in Crossville, AL. Treatments included two methods of litter application (surface broadcast and subsurface banding), commercial fertilizer, and control. Litter was applied at a rate of 8.97 Mg ha(-1). Treatments were assigned to 48 plots with four blocks (12 plots each) arranged in a randomized complete block design to include three replications in each block. Simulated rainfall was applied to treatments as follows: Day 1, block 1 (runoff 1); Day 8, block 2 (runoff 2); Day 15, block 3 (runoff 3); and Day 22, block 4 (runoff 4). Total phosphorus (TP), inorganic N, and Escherichia coli concentrations in runoff from broadcast litter application were all significantly greater than from subsurface litter banding. The TP losses from broadcast litter applications averaged 6.8 times greater than those from subsurface litter applications. About 81% of the runoff TP was in the form of dissolved reactive phosphorus (DRP) for both litter-application methods. The average losses of NO(3)-N and total suspended solids (TSS) from subsurface banding plots were 160 g ha(-1) and 22 kg ha(-1) compared to 445 g ha(-1) and 69 kg ha(-1) for the broadcast method, respectively. Increasing the time between litter application and the first runoff event helped decrease nutrient and E. coli losses from surface broadcast litter, but those losses generally remained significantly greater than controls and subsurface banded, regardless of runoff timing. This study shows that subsurface litter banding into perennial grassland can substantially reduce nutrient and pathogen losses in runoff compared to the traditional surface-broadcast practice. PMID:19398519

Sistani, K R; Torbert, H A; Way, T R; Bolster, C H; Pote, D H; Warren, J G

2009-01-01

420

Study of nano imprinting using soft lithography on Krafty glue & PVDF polymer thin films  

NASA Astrophysics Data System (ADS)

The present work reveals soft lithography strategy based on self assembly and replica molding for carrying out micro and nanofabrication. It provides a convenient, effective and very low cost method for the formation and manufacturing of micro and nano structures. Al-layer of compact disc (sony CD-R) used as a stamp with patterned relief structures to generate patterns and structures with pattern size of 100nm height, 1.7 ?m wide. In literature, PDMS (Polydimethylsiloxane) solution is widely used to get negative copy of the Al-layer. In this work, we have used inexpensive white glue (Polyvinylacetate + water), 15gm (?5) and PVDF (Polyvinylidene difluoride) spin coated films and successfully transferred the nano patterns of Al layer on to white glue and PVDF films.

Sankar, M. S. Ravi; Gangineni, Ramesh Babu

2014-04-01

421

Nano-encapsulations liberated from barley protein microparticles for oral delivery of bioactive compounds.  

PubMed

Novel microparticles (3-5 ?m) were created by pre-emulsifying barley proteins with a homogenizer followed a microfluidizer system. These microparticles exhibited a high oil carrying capacity (encapsulation efficiency, 93-97%; loading efficiency, 46-49%). Microparticle degradation and bioactive compound release behaviours were studied in the simulated gastro-intestinal (GI) tract. The data revealed that nano-encapsulations (20-30 nm) were formed as a result of enzymatic degradation of barley protein microparticle bulk matrix in the simulated gastric tract. These nano-encapsulations delivered ?-carotene to a simulated human intestinal tract intact, where they were degraded by pancreatic enzymes and steadily released the ?-carotene. These uniquely structured microparticles may provide a new strategy for the nutraceutical and pharmaceutical industries to develop targeted delivery systems for lipophilic bioactive compounds. PMID:21219995

Wang, Ruoxi; Tian, Zhigang; Chen, Lingyun

2011-03-15

422

Reactive oxygen species-related activities of nano-iron metal and nano-iron oxides.  

PubMed

Nano-iron metal and nano-iron oxides are among the most widely used engineered and naturally occurring nanostructures, and the increasing incidence of biological exposure to these nanostructures has raised concerns about their biotoxicity. Reactive oxygen species (ROS)-induced oxidative stress is one of the most accepted toxic mechanisms and, in the past decades, considerable efforts have been made to investigate the ROS-related activities of iron nanostructures. In this review, we summarize activities of nano-iron metal and nano-iron oxides in ROS-related redox processes, addressing in detail the known homogeneous and heterogeneous redox mechanisms involved in these processes, intrinsic ROS-related properties of iron nanostructures (chemical composition, particle size, and crystalline phase), and ROS-related bio-microenvironmental factors, including physiological pH and buffers, biogenic reducing agents, and other organic substances. PMID:24673906

Wu, Haohao; Yin, Jun-Jie; Wamer, Wayne G; Zeng, Mingyong; Lo, Y Martin

2014-03-01

423

Report of International NanoSPD Steering Committee and statistics on recent NanoSPD activities  

NASA Astrophysics Data System (ADS)

Abstract. The Université de Lorraine in Metz, France, is the selected site for the 6th International Conference on Nanomaterials by Severe Plastic Deformation (NanoSPD6) following a series of five earlier conferences. This introductory paper reports on several major developments in NanoSPD activities as well as on very recent NanoSPD citation data which confirm the continued growth and expansion of this important research area. Close attention is given to the topics of workshops, conferences and seminars organized during these last three years as well as on books and reviews published prior to the NanoSPD6 conference. A special concern of the committee is in introducing and discussing the appropriate terminology to be applied in this new field of materials science and engineering.

2014-08-01

424

Every which way--nanos gene regulation in echinoderms.  

PubMed

Nanos is an essential factor of germ line success in all animals tested. This gene encodes a Zn-finger RNA-binding protein that in complex with its partner pumilio binds to and changes the fate of several known transcripts. We summarize here the documented functions of Nanos in several key organisms, and then emphasize echinoderms as a working model for how nanos expression is regulated. Nanos presence outside of the target cells is often detrimental to the animal, and in sea urchins, nanos expression appears to be regulated at every step of transcription, and post-transcriptional activity, making this gene product exciting, every which way. PMID:24376110

Oulhen, Nathalie; Wessel, Gary M

2014-03-01

425

Thermal plasma synthesis of SiC nano-powders\\/nano-fibers  

Microsoft Academic Search

Thermal plasma synthesis of nano-powders\\/nano-fibers is a relatively new technology with great potential for future application in industries. The paper presents the effects of molar ratio on synthesis of SiC by thermal plasma technology. The experimental results show that SiC can be synthesized by thermal plasma technology. The average size of SiC powders is less than 100nm and SiC fiber-like

Lirong Tong; Ramana G. Reddy

2006-01-01

426

Microfluidic size selective growth of palladium nano-particles on carbon nano-onions.  

PubMed

Size selective growth of palladium nano-particles 2-7 nm in diameter on the surface of carbon nano-onions (CNOs) (derived from catalytic cracking of methane) in water involves pretreating the CNOs with p-phosphonic acid calix[8]arene then H(2)PdCl(4) followed by dynamic thin film processing under hydrogen in a vortex fluidic device. PMID:22957341

Yasin, Faizah Md; Boulos, Ramiz A; Hong, Boon Yong; Cornejo, Andrew; Iyer, K Swaminathan; Gao, Lizhen; Chua, Hui Tong; Raston, Colin L

2012-10-18

427

Coupling mechanisms in nano-U dimers  

NASA Astrophysics Data System (ADS)

Properties of split-ring metamaterials are governed by inter-element interactions. These interactions lead to slow eigenmodes of coupling, which, due to their short wavelengths, are ideal candidates for the design of near-field manipulating devices. In this paper we explore the electric and magnetic coupling mechanisms in nano-U and nano-SRR dimers comprising of two identical nano-resonators arranged axially and twisted relative to each other by an arbitrary angle. We study theoretically the couplings in a periodic chain of nano-dimers for the frequencies from 100 to 300 THz. In our analytical model, the electric and magnetic couplings can be expressed through the self and mutual terms for the magnetic and electric field energy. In addition, we incorporate the effect of kinetic inductance due to the inertia of the electrons (noticeable as element dimensions approach 100nm or smaller). The resulting dependence of the electric, magnetic and the total coupling constants on the twist angle within the dimer obtained analytically is shown to agree with numerical simulations (CST Microwave Studio). Our approach should enable an effective design of metamaterial structures with desired properties and would be a useful tool in developing THz range manipulating devices based on propagation of slow waves by virtue of coupling.

Gneiding, N.; Krutkova, E.; Tatartschuk, E.; Zhuromskyy, O.; Shamonina, E.

2011-10-01

428

The Internet of nano-things  

Microsoft Academic Search

Nanotechnology promises new solutions for many applications in the biomedical, industrial and military fields as well as in consumer and industrial goods. The interconnection of nanoscale devices with existing communication networks and ultimately the Internet defines a new networking paradigm that is further referred to as the Internet of Nano-Things. Within this context, this paper discusses the state of the

I. F. Akyildiz; J. M. Jornet

2010-01-01

429

Nano-plasmonic biosensors: A review  

Microsoft Academic Search

In this paper, first the fundamental concept of nano-optical biosensing is studied. Since Raman scattered signal is very weak to be recognized by current measuring equipments, the signal must be amplified. SPR and LSPR are utilized to enhance the incident field of the target molecules, to improve the sensitivity of the sensor. The paper focuses on the use of LSPR

Daryoush Mortazavi; Abbas Z. Kouzani; Akif Kaynak; Wei Duan

2011-01-01

430

We Scream for Nano Ice Cream  

ERIC Educational Resources Information Center

There is a wide range of new products emerging from nanotechnology, and "nano ice cream" is an easy one that you can use to teach topics from surface area to volume applications. In this activity, students learn how ice cream can be made smoother and creamier tasting through nanoscience. By using liquid nitrogen to cool the cream mixture, students…

Jones, M. Gail; Krebs, Denise L.; Banks, Alton J.

2011-01-01

431

Bio-nano-optics for cellular investigations  

Microsoft Academic Search

We report results of our recent efforts to develop nano-tools to study proteins and their interactions in complex environments that exist on the cell membrane and inside the cells. Due to the spatial constraints imposed on the mobility of cell constituents, it is reasonable to expect that the nature and dynamics of the biomolecular interactions in a living cell would

Mark R. Contarino; Vishal Kamat; Edward Keough; Nadaraj S. Babu; Mauro Sergi; Tetsuya Ishino; Elisabeth Papazoglou; Irwin M. Chaiken; Som Tyagi; Kambiz Pourrezaei

2004-01-01

432

Nanotubes, Nanowires and Nano-electronics  

E-print Network

In current computer hardware, logic gates and wires a fraction of a micron wide are fabricated onto a silicon the confinement, the more marked the quantum-mechanical properties. Nanowires of silicon and other inorganic promising light sensitivity, and which could be used for developing future solar cells. Advances in Nano-computing

Pulfrey, David L.

433

Nano-holes for vacuum applications  

NASA Astrophysics Data System (ADS)

In order to calibrate leak-detection instruments, devices based on permeation leaks and physical leaks are used. Unfortunately, permeation leaks are very sensitive to small temperature fluctuations and can be used only with those gases for which permeating materials are available. While, physical-leaks that overcome these restrictions are susceptible to clog, in particular when the gas flow through them is in viscous regime. Furthermore, for many type of leak devices, the conductance is not predictable based on dimensional, gas species and temperature data, for this reason no estimates or only rough estimates of leak rates are possible for conditions under use where they differ from those of the calibration. Here, we present the fabrication and characterization of a new kind of physical-leak devices based on nano-holes, which overcome these problems. Nano-holes, with diameters less than or equal to 200 nm, work in molecular-flow regime up to atmospheric pressure and for this reason they do not clog. The nano-holes are manufactured by milling a silicon nitride membrane by means of Focused Ion Beam (FIB), and their shapes are characterized by both Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Because of the capability of the AFM to acquire surface three-dimensional images with very high resolution, it is a very useful tool to perform a topographic characterization of the nano-holes.

Ierardi, V.; Firpo, G.; Valbusa, U.

2013-06-01

434

Modeling of nano-photonics Elefterios Lidorikisa  

E-print Network

Modeling of nano-photonics Elefterios Lidorikisa , Michelle L. Povinellia , Steven G. Johnsona-insensitive waveguide networks. b) Using nonlinear materials, a cylindrical photonic crystal fiber is designed that can, optical fibers are the preferred medium for transportation, due to their low losses, and high capacity

435

Green Chemistry by Nano-Catalysis  

EPA Science Inventory

The approach of using MW technique with nano-catalysis and benign aqueous reaction medium can offer an extraordinary synergistic effect with greater potential than these three individual components in isolation. To illustrate the ??proof-of-concept?? of this ?Green and Sustainabl...

436

Nuclear microbatteries for micro and nano Devices  

Microsoft Academic Search

Radioisotopes have many applications. Among the various technologies for micro power generation being investigated, nuclear microbatteries that convert the kinetic energy of charged particles emitted from the radioisotopes into electricity are very attractive for many applications. In this paper, the previous work on developing nuclear microbatteries for micro and nano devices, including two types of microbatteries, betavoltaic microbatteries and direct

Hang Guo; Hui Li; A. Lal; J. Blanchard

2008-01-01

437

TTC integrated subsystem for nano-satellites  

Microsoft Academic Search

Small spacecraft evolution from microsatellites down to nano-satellites naturally demands lower mass, volume and power consumption platforms which requires the use of low power consumption design and technologies. However, there is also a demand of increased robustness against the radiation environment of relatively low elevation orbits in particular for high energy ions. This paper introduces the design and performances of

Javier Cabo; Juan Cueto; Cesar Martinez; Fany Sarmiento; Ricardo Amaro

2011-01-01

438

Growth of decorated carbon nano-tubes  

Microsoft Academic Search

Decomposition of methane in a nitrogen atmosphere using bias-enhanced hot filament chemical vapour deposition results in the growth of nitrogenated carbon tubes. Different shapes were formed ranging from spherical aggregates to twisted nano-tubes. All these structures were grown direct onto pure Si wafer. Glow discharge optical emission spectroscopy reveals the presence of tungsten carbide impurities at the interface. Graphitic sheets

Ralph Kurt; Ayatollah Karimi; Volker Hoffmann

2001-01-01

439

Nano-Fiber Reinforced Enhancements in Composite Polymer Matrices  

NASA Technical Reports Server (NTRS)

Nano-fibers are used to reinforce polymer matrices to enhance the matrix dependent properties that are subsequently used in conventional structural composites. A quasi isotropic configuration is used in arranging like nano-fibers through the thickness to ascertain equiaxial enhanced matrix behavior. The nano-fiber volume ratios are used to obtain the enhanced matrix strength properties for 0.01,0.03, and 0.05 nano-fiber volume rates. These enhanced nano-fiber matrices are used with conventional fiber volume ratios of 0.3 and 0.5 to obtain the composite properties. Results show that nano-fiber enhanced matrices of higher than 0.3 nano-fiber volume ratio are degrading the composite properties.

Chamis, Christos C.

2009-01-01

440

Biomedical applications of nano-antioxidant.  

PubMed

For centuries now, antioxidants have been known to provide better health by neutralizing the free radicals which are continuously produced in the human body. In normal circumstances, self-antioxidant defense system of the human body is capable of quantitatively managing the free radicals. However, in certain cases, which are at the threshold of developing diseases like diabetes and Alzheimer's, the human body calls for an external source of antioxidants. Since orally delivered antioxidants are easily destroyed by acids and enzymes present in the human system, only a small portion of what is consumed actually gets absorbed. Hence, there is a recognized and urgent need to develop effective methods for efficiently delivering antioxidants to the required sites. This chapter provides an in-depth overview and analysis of two such methods and processes-nano-encapsulation and nano-dendrimers. Among the various nanoscale delivery mechanisms, nano-encapsulation has emerged as a key and efficient delivery process. Designed as a spongelike polymer, nano-encapsulated antioxidants provide a protective vehicle which keeps antioxidants from being destroyed in the human gut and ensures their better absorption in the digestive tract. In fact, the nano-capsules bind themselves to the intestinal walls and pour antioxidants directly into the intestinal cells, which allow them to be absorbed directly into the blood stream. Another distinguished and popular mode for delivering antioxidants is that of nano-polymers known as dendrimers. Dendrimers involve multiple branches and sub-branches of atoms radiating out from a central core. Dendrimers afford a high level of control over their architectural design, including their size, shape, branching length or density, and surface functionality. Such flexibility makes these nanostructures ideal carriers in biomedical applications such as drug delivery, gene transfection, and imaging. Antioxidant dendrimers, made out of numerous units of antioxidants connected with each other in a branched fashion, provide numerous possible sites to couple with an active species and have enhanced free radicals scavenging potency. These dendrimer chains are biocompatible, biodegradable with nontoxic degradation products, and well suited for targeted drug delivery and other biomedical applications. Recent successes in simplifying and optimizing the synthesis of dendrimers, such as the "lego" and "click" approaches, provide a large variety of structures while at the same time reducing the cost of their production. The use of these highly branched, nanometer-sized, polymeric materials as nano-antioxidants for prevention and treatment of human diseases, associated with oxidative stress, is of immense public health relevance globally. PMID:23740118

Watal, Geeta; Watal, Aparna; Rai, Prashant Kumar; Rai, Devendra Kumar; Sharma, Gaurav; Sharma, Bechan

2013-01-01

441

A NANO enhancement to Moore's law  

NASA Astrophysics Data System (ADS)

In the past 46 years, Intel Moore observed an exponential doubling in the number of transistors in every 18 months through the size reduction of individual transistor components since 1965. In this paper, we are exploring the nanotechnology impact upon the Law. Since we cannot break down the atomic size barrier, the fact implies a fundamental size limit at the atomic or Nanotechnology scale. This means, no more simple 18 month doubling as in Moore's Law, but other forms of transistor doubling may happen at a different slope in new directions. We are particularly interested in the Nano enhancement area. (i) 3-D: If the progress in shrinking the in-plane dimensions (2D) is to slow down, vertical integration (3D) can help increasing the areal device transistor density and keep us on the modified Moore's Law curve including the 3rd dimension. As the devices continue to shrink further into the 20 to 30 nm range, the consideration of thermal properties and transport in such nanoscale devices becomes increasingly important. (ii) Carbon Computing: Instead of traditional Transistors, the other types of transistors material are rapidly developed in Laboratories Worldwide, e.g. IBM Spintronics bandgap material and Samsung Nano-storage material, HD display Nanotechnology, which are modifying the classical Moore's Law. We shall consider the overall limitation of phonon engineering, fundamental information unit 'Qubyte' in quantum computing, Nano/Micro Electrical Mechanical System (NEMS), Carbon NanoTubes (CNTs), single layer Graphemes, single strip Nano-Ribbons, etc., and their variable degree of fabrication maturities for the computing and information processing applications.

Wu, Jerry; Shen, Yin-Lin; Reinhardt, Kitt; Szu, Harold

2012-06-01

442

Novel use of an exchange catheter to facilitate intubation with an Aintree catheter in a tall patient with a predicted difficult airway: a case report  

PubMed Central

Introduction The Aintree intubating catheter (Cook® Medical Inc., Bloomington, IN, USA) has been shown to successfully facilitate difficult intubations when other methods have failed. The Aintree intubating catheter (Cook® Medical Inc., Bloomington, IN, USA) has a fixed length of 56 cm, and it has been suggested in the literature that it may be too short for safe use in patients who are tall. Case presentation We present the case of a 32-year-old, 180 cm tall Caucasian woman with a predicted difficult airway who presented to our facility for an emergency cesarean section. After several failed intubation attempts via direct laryngoscopy, an airway was established with a laryngeal mask airway. After delivery of a healthy baby, our patient's condition necessitated tracheal intubation. A fiber-optic bronchoscope loaded with an Aintree intubating catheter (Cook® Medical Inc., Bloomington, IN, USA) was passed through the laryngeal mask airway into the trachea until just above the carina, but was too short to safely allow for the passage of an endotracheal tube. Conclusions We present a novel technique in which the Aintree intubating catheter (Cook® Medical Inc., Bloomington, IN, USA) was replaced with a longer (100 cm) exchange catheter, over which an endotracheal tube was passed successfully into the trachea. PMID:22502764

2012-01-01

443

Improvement of open and semi-open core wall system in tall buildings by closing of the core section in the last story  

NASA Astrophysics Data System (ADS)

Increasing number of tall buildings in urban population caused development of tall building structures. One of the main lateral load resistant systems is core wall system in high-rise buildings. Core wall system has two important behavioral aspects where the first aspect is related to reduce the lateral displacement by the core bending resistance and the second is governed by increasing of the torsional resistance and core warping of buildings. In this study, the effects of closed section core in the last story have been considered on the behavior of models. Regarding this, all analyses were performed by ETABS 9.2.v software (Wilson and Habibullah). Considering (a) drift and rotation of the core over height of buildings, (b) total and warping stress in the core body, (c) shear in beams due to warping stress, (d) effect of closing last story on period of models in various modes, (e) relative displacement between walls in the core system and (f) site effects in far and near field of fault by UBC97 spectra on base shear coefficient showed that the bimoment in open core is negative in the last quarter of building and it is similar to wall-frame structures. Furthermore, analytical results revealed that closed section core in the last story improves behavior of the last quarter of structure height, since closing of core section in the last story does not have significant effect on reducing base shear value in near and far field of active faults.

Kheyroddin, A.; Abdollahzadeh, D.; Mastali, M.

2014-09-01

444

Development of CMC hydrogels loaded with silver nano-particles for medical applications.  

PubMed

Innovative CMC-based hydrogels with great potentials for usage in medical area were principally synthesized as per two strategies .The first involved reaction of epichlorohydrin in alkaline medium containing silver nitrate to yield silver nano-particles (AgNPs)-loaded CMC hydrogel. While CMC acted as stabilizing for AgNPs, trisodium citrate was added to the reaction medium to assist CMC in establishing reduction of Ag(+) to AgNPs. The second strategy entailed preparation of CMC hydrogel which assists the in situ preparation of AgNPs under the same conditions. In both strategies, factors affecting the characterization of AgNPs-loaded CMC hydrogels were studied. Analysis and characterization of the so obtained hydrogels were performed through monitoring swelling behavior, FTIR spectroscopy, SEM, EDX, UV-vis spectrophotometer and TEM. Antimicrobial activity of the hydrogels was examined and mechanisms involved in their synthesis were reported. PMID:23218313

Hebeish, Ali; Hashem, M; El-Hady, M M Abd; Sharaf, S

2013-01-30

445

Chemical interactions between Nano-ZnO and Nano-TiO2 in a natural aqueous medium.  

PubMed

The use of diverse engineered nanomaterials (ENMs) potentially leads to the release of multiple ENMs into the environment. However, previous efforts to understand the behavior and the risks associated with ENMs have focused on only one material at a time. In this study, the chemical interactions between two of the most highly used ENMs, nano-TiO2, and nano-ZnO, were examined in a natural water matrix. The fate of nano-ZnO in Lake Michigan water was investigated in the presence of nano-TiO2. Our experiments demonstrate that the combined effects of ZnO dissolution and Zn adsorption onto nano-TiO2 control the concentration of dissolved zinc. X-ray absorption spectroscopy was used to determine the speciation of Zn in the particulate fraction. The spectra show that Zn partitions between nano-ZnO and Zn2+ adsorbed on nano-TiO2. A simple kinetic model is presented to explain the experimental data. It integrates the processes of nano-ZnO dissolution with Zn adsorption onto nano-TiO2 and successfully predicts dissolved Zn concentration in solution. Overall, our results suggest that the fate and toxicity potential of soluble ENMs, such as nano-ZnO, are likely to be influenced by the presence of other stable ENMs, such as nano-TiO2. PMID:24918623

Tong, Tiezheng; Fang, Kaiqi; Thomas, Sara A; Kelly, John J; Gray, Kimberly A; Gaillard, Jean-François

2014-07-15

446

Joining NanoSIMS and STXM/NEXAFS to visualize soil biotic and abiotic processes at the nano-scale  

NASA Astrophysics Data System (ADS)

Understanding the fate and residence time of organic matter in soils is important to natural resource management, including strategies to mitigate climate change. The time scales of carbon cycling, the relative importance of biotic and abiotic processes in organic matter stabilization in soils, and spatial factors in these processes are all critical characteristics that currently cannot be addressed by any single analytical approach. Here we demonstrate how many of these concerns can be approached by a combination of high-resolution secondary ion mass spectroscopy (NanoSIMS) and Scanning Transmission X-ray Microscopy (STXM) coupled with Near Edge X-ray Absorption Fine Structure spectroscopy (NEXAFS). When used in concert, these analytical techniques have the capacity to yield quantitative, in situ information on the source, molecular class, and elemental quantity of organic matter. We: (i) discuss the rationale for the joined application of the two procedures, (ii) provide examples for the their combined application, (iii) point out some of the methodological caveats that warrant consideration, and (iv) provide some directions for future developmental efforts. To illustrate the synergies of this combined approach, we examined organic-mineral associations in samples from both an artificial well-defined mixture and an unconstrained natural soil decomposition experiment. Case 1 demonstrates how the joined techniques help to determine modes of interaction between 13C- and 15N-labeled microorganisms and a defined mineral phase;, in case 2 we examine the incorporation of a 15N label into mineral organic associations 12 years after application to a forest soil. This unique analytical combination, the simultaneous application of STXM/NEXAFS and NanoSIMS imaging, has the potential to contribute a mechanistic understanding of sorption, occlusion, and decomposition processes that operate at fine spatial scales in natural environments.

Pett-Ridge, J.; Keiluweit, M.; Bougoure, J.; Weber, P. K.; Kleber, M.; Nico, P.

2012-04-01

447

On return stroke currents and remote electromagnetic fields associated with lightning strikes to tall structures: 2. Experiment and model validation  

NASA Astrophysics Data System (ADS)

In this paper, simultaneous GPS time-stamped measurements of the electric and magnetic fields at three distances and of the return stroke current associated with lightning strikes to the Toronto CN Tower (553 m) during the summer of 2005 are presented. The lightning return stroke current was measured using a Rogowski coil installed at a height of 474 m above ground level (AGL). The vertical component of the electric field and the azimuthal component of the magnetic field were measured simultaneously at distances of 2.0 km, 16.8 km, and 50.9 km from the CN Tower. The propagation path from the CN Tower to the first two stations (2.0 and 16.8 km) was along the soil and through the Toronto city, whereas for the third location (50.9 km) the propagation path was nearly entirely across Lake Ontario. The waveforms of the electric and magnetic fields at 16.8 km and 50.9 km exhibit a first zero crossing about 5 ?s after the onset of the return stroke. This early zero crossing is part of a narrow undershoot. For fields at 50.9 km the expected zero crossing at about 40 ?s is also observed. Metallic beams and other conducting parts in buildings on which electric and magnetic field sensors were located cause an enhancement effect on the measured fields. Although an enhancement can be identified both on the electric and the magnetic fields, the degree of enhancement is actually more significant for the electric field than for the magnetic field. It is shown that the value of the wave impedance (E-field peak to H-field peak ratio) could give an estimate of the enhancement effect of the building on the electric field. Propagation effects (decrease of field amplitude and increase of its risetime) can also be observed in experimental records. It is shown that the fields at 50.9 km are less affected by such attenuation, compared to those at 16.8 km, presumably because the path of propagation is mostly across Lake Ontario. Measured waveforms are compared with theoretical predictions obtained using the five engineering return stroke models extended to include the presence of the strike object, namely, transmission line (TL), modified transmission line (MTLL and MTLE), Bruce-Golde (BG), and traveling current source (TCS) models. A reasonable agreement is found with all five engineering models for the magnetic field waveforms at the three considered distances, although the peak values of the computed fields are systematically about 25% lower than measured values. None of the models was able to reproduce the early zero crossing and the narrow undershoot. As far as the electric field is concerned, larger differences have been observed between simulations and measurements. This may be due to the fact that the enhancement effect of the building on the electric field is stronger than that on the magnetic field. The expression relating current and field peaks associated with strikes to tall structures is also tested versus obtained sets of experimental data. The overall agreement between the theoretically predicted and the experimentally observed field-to-current ratio is reasonable, although the formula of Bermudez et al. (2005) appears also to underestimate the experimentally measured ratio (by about 25%). This may be due, at least in part, to the enhancement effect of the buildings on which the field measurement antennae were installed.

Pavanello, D.; Rachidi, F.; Janischewskyj, W.; Rubinstein, M.; Hussein, A. M.; Petrache, E.; Shostak, V.; Boev, I.; Nucci, C. A.; Chisholm, W. A.; Nyffeler, M.; Chang, J. S.; Jaquier, A.

2007-07-01

448

Synthesis of gold nano-wire and nano-dumbbell shaped colloids and AuC60 nano-clusters  

NASA Astrophysics Data System (ADS)

A technique for the fabrication of colloidal gold nano-wire and nano-dumbbell shaped particles using carbon nanotubes and rod shaped viruses as templates is described. The gold (Au) encapsulation process was accomplished by the precipitation of gold chloride from aqueous solutions. When this process was conducted in the presence of hydroxylated C60, small pieces of phase-separated composites of AuC60 appeared to have formed. These nano-clusters may turn out to be large noble metal analogs of the alkali metal fullerides with the smallest geometrically possible Au aggregate consisting of 55 gold atoms. The existence of noble metal fullerene composites has been previously theorized. The